11,158 results on '"Alexander O"'
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2. Advances in radical peroxidation with hydroperoxides
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Oleg V. Bityukov, Pavel Yu. Serdyuchenko, Andrey S. Kirillov, Gennady I. Nikishin, Vera A. Vil’, and Alexander O. Terent’ev
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c–h functionalization ,oxidation ,peroxidation ,radical reactions ,tbhp ,Science ,Organic chemistry ,QD241-441 - Abstract
Organic peroxides have become sought-after functionalities, particularly following the multi-tone consumption in polymer production and success in medicinal chemistry. The selective introduction of a peroxide fragment at different positions on the target molecule is a priority in the modern reaction design. The pioneering Kharasch–Sosnovsky peroxidation became the basic universal platform for the development of peroxidation methods, with its great potential for rapid generation of complexity due to the ability to couple the resulting free radicals with a wide range of partners. This review discusses the recent advances in the radical Kharasch-type functionalization of organic molecules with OOR fragment including free-component radical couplings. The discussion has been structured by the type of the substrate of radical peroxidation: C(sp3)–H substrates; aromatic systems; compounds with unsaturated C–C or C–Het bonds.
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- 2024
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3. Patagomaia could be a gondwanatherian
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Hans P. Püschel, Agustín G. Martinelli, Sergio Soto-Acuña, and Alexander O. Vargas
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Medicine ,Science - Published
- 2024
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4. Lassa fever in Nigeria: epidemiology and risk perception
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Ahmad I Al-Mustapha, Ibukun Modupe Adesiyan, Terese Gabriel Orum, Oluwaseun A. Ogundijo, Adedeji Nurudeen Lawal, Okechi E. Nzedibe, Libby O. Onyeka, Kabiru U Muhammad, Lateefah Odetayo, Muftau Oyewo, Shuaibu Osu Muhammad, Everest O. Atadiose, L Icomiare Adebudo, D Adeolu Adetunji, Hamman Joseph Jantiku, Alexander O. Akintule, Raymond C Nwachukwu, and Ahmed Tijani Abubakar
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LASV ,Lassa ,Nigeria ,Rodent ,LF ,Medicine ,Science - Abstract
Abstract Annual outbreaks of Lassa fever have resulted in a public health threat in Nigeria and other endemic countries in Sub-Saharan Africa. While the Lassa Virus (LASV) is endemic in rodent populations, zoonotic spillover to humans causes annual outbreaks. This study reviewed the burden of Lassa fever (LF) in Nigeria between 2020 and 2023 and conducted a cross-sectional survey of Nigerians to evaluate their risk perceptions of LF. During the period under review, 28,780 suspected and 4,036 confirmed cases of LF were reported from 34 of the 37 states of Nigeria. These cases resulted in 762 deaths (a CFR of 18.9%). The overall case positivity rate was 14% (4,036/28,780), with more positive cases in 2020 (17.5%, n = 1,189/6,791). A total of 2,150 study participants were enrolled in the prospective cross-sectional study, with most of them (87.5%, n = 1,881/2,150) having previously heard of Lassa fever (LF). The numerical scoring system revealed that 35.43% (n = 762/1,881) of those aware of LF have poor knowledge of its preventive measures, route of transmission, and control measures. Approximately 6.84% (n = 147/2,150) of them were at a high risk of contracting LF, with 27.6% (n = 584/2,150) of study participants feeling concerned about contracting LF because of the presence of rodents in their immediate vicinity, occupational exposure to healthcare workers, and the probability of contamination of food by infected rodents without necessary food safety measures. Multivariable logistic regression analysis revealed that tertiary education was associated with an increased likelihood of better LF knowledge (OR: 17.32; 95% CI: 10.62, 28.26; p
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- 2024
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5. Lifetime healthcare expenditures across socioeconomic groups
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Malene Kallestrup-Lamb and Alexander O. K. Marin
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Lifetime healthcare expenditures ,Socioeconomic groups ,Inequality ,Social gradient ,Mortality ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background A socioeconomic gradient affects healthcare expenditures and longevity in opposite directions as less affluent individuals have higher current healthcare expenditures but simultaneously enjoy shorter lives. Yet, it is unclear whether this cross-sectional healthcare expenditure gradient persists from a lifetime perspective. This paper analyzes lifetime healthcare expenditures across socioeconomic groups using detailed individual-level healthcare expenditure data for the entire Danish population. Method Using full population healthcare expenditures from Danish registries, we estimate lifetime healthcare expenditures as age-specific mean healthcare expenditures times the probability of being alive at each age. Our data enables the estimation of lifetime healthcare expenditures by sex, socioeconomic status, and by various types of healthcare expenditure. Results Once we account for mortality differences and all types of healthcare expenditures, all socioeconomic groups spend an almost equal amount on healthcare throughout a lifetime. Lower socioeconomic groups incur the lowest lifetime hospital expenditures, whereas higher socioeconomic groups experience the highest lifetime expenditures on long-term care services. Our findings remain robust across various socioeconomic measures and alternative estimation methodologies. Conclusion Improving the health status of lower socioeconomic groups to align with that of higher socioeconomic groups is costly but may ultimately reduce current healthcare expenditures. Enhanced health outcomes likely increase lifespan, leading to extended periods of healthcare consumption. However, since all socioeconomic groups tend to have similar lifetime healthcare expenditures, this prolonged consumption has limited impact on overall lifetime healthcare costs. Additionally, a significant benefit is the deferment of healthcare expenditures into the future. Overall, our results diminish concerns about socially inequitable utilization of healthcare resources while socioeconomic differences in health and longevity persist, even in a universal healthcare system.
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- 2024
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6. Macrocyclic Organic Peroxides: Constructing Medium and Large Cycles with O-O Bonds
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Yana A. Barsegyan, Vera A. Vil’, and Alexander O. Terent’ev
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macrocycles ,ozonolysis ,peroxidation ,organic peroxides ,rearrangement ,hydroperoxides ,Chemistry ,QD1-999 - Abstract
Macrocycles bridge the gap between conventional small molecules and polymers. Drawing inspiration from successful carbon heteroatom-containing macrocycles, peroxide-containing macrocycles are gaining attention for enhanced bioactivity, potential chelating properties, and applications in energetic materials. This review presents the following strategies for the construction of cyclic peroxides with 10- to 36-membered frameworks: (1) the intramolecular iodocyclization of hydroperoxides, (2) the intermolecular cyclization of hydroperoxides with alkyl dihalides or carbonyls, (3) the acid-catalyzed rearrangements of ozonides or 11-membered cyclic triperoxides via oxy- or peroxycarbenium ions, and (4) the peroxidation of carbonyls targeting macrocyclic peroxides. The specific agents that allow for the selective construction of the medium and large cycles are also analyzed.
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- 2024
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7. An Acinetobacter baumannii nasal carriage isolate recovered from an asymptomatic patient in Vietnam is extensively antibiotic resistant and produces a rare K71 type capsule
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Anna M. Shpirt, Christopher J. Harmer, Alexander S. Shashkov, Mikhail M. Shneider, Alexander O. Chizhov, Andrey S. Dmitrenok, Anastasiya V. Popova, Anastasiya A. Kasimova, Andrei V. Perepelov, Yuriy A. Knirel, Ruth M. Hall, and Johanna J. Kenyon
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Acinetobacter baumannii ,capsular polysaccharide ,K locus ,K71 ,rhamnose ,Microbiology ,QR1-502 - Abstract
ABSTRACT Acinetobacter baumannii is a leading cause of multidrug-resistant bacterial infections worldwide, and the capsular polysaccharide (CPS) is a major virulence determinant. A previous study of A. baumannii from intubated and asymptomatic patients admitted to the intensive care unit (ICU) at the Hospital for Tropical Diseases in Ho Chi Minh City in Vietnam revealed multiple lineages with diverse antibiotic resistance profiles and CPS biosynthesis loci. Here, we show that 48_n, an asymptomatic nasal carriage isolate belonging to ST142, is extensively antibiotic resistant and carries acquired resistance determinants accounting for the resistance profile. 48_n carries the novel KL71 CPS biosynthesis locus in the chromosome. The structure of the CPS produced by 48_n was established using 1H and 13C nuclear magnetic resonance spectroscopy, including two-dimensional 1Н,1Н COSY, 1Н,1Н TOCSY, 1Н,1Н ROESY, 1Н,13C HSQC, and 1Н,13C HMBC experiments, and confirmed by Smith degradation. Consistent with the genetic content of KL71, the K71 CPS was found to be made up of octasaccharide K units containing six l-rhamnose residues and one residue each of N-acetyl-d-glucosamine and d-glucuronic acid. K71 CPS was branched and closely related to the K74 CPS produced by BAL_309, an antibiotic susceptible ST142 isolate recovered from an intubated patient in the same ICU 7 years later. K71 and K74 differ only in the linkage between K units, and this is due to the replacement of a single gene at the K locus that codes for the Wzy polymerase.IMPORTANCEThe majority of Acinetobacter baumannii genomes sequenced and analyzed to develop an understanding of extensively drug-resistant (XDR) isolates belong to the globally disseminated CC2 clonal complex. While XDR isolates belonging to rarer lineages are often unexplored, detailed analyses could provide novel insights into the spread of resistance, as well as cell surface features such as the CPS that determine the specificity of non-antibiotic therapeutics required to treat XDR infections that resist antimicrobial chemotherapy. Here, we describe the properties of an XDR asymptomatic nasal carriage isolate recovered in Vietnam that belongs to ST142, a rarely encountered sequence type. We report the resistance profile and correlate this with detected resistance determinants. We also solve the structure of the CPS and reveal its relationship with CPS produced by other A. baumannii isolates.
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- 2024
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8. Cognitive–behavioural conjoint therapy versus prolonged exposure for PTSD in military service members and veterans: results and lessons from a randomized controlled trial
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Candice M. Monson, Nicole D. Pukay-Martin, Anne C. Wagner, Alexander O. Crenshaw, Tabatha H. Blount, Richard P. Schobitz, Katherine A. Dondanville, Stacey Young-McCaughan, Jim Mintz, David S. Riggs, Antoinette Brundige, Elizabeth A. Hembree, Brett T. Litz, John D. Roache, Jeffrey S. Yarvis, and Alan L. Peterson
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Military ,PTSD ,treatment ,prolonged exposure ,cognitive–behavioural conjoint therapy ,couple therapy ,Psychiatry ,RC435-571 - Abstract
ABSTRACTBackground: Military personnel and veterans are at heightened risk for exposure to traumatic events and posttraumatic stress disorder (PTSD), as well as intimate relationship problems associated with PTSD.Objective: The purpose of this study was to evaluate the relative efficacy of CBCT and PE in improving intimate relationship functioning in active duty military personnel or veterans and their intimate partners; both conditions were hypothesized to significantly improve PTSD. Method: In this study, 32 military service members or veterans with PTSD and their intimate partners were randomized to receive either Cognitive–Behavioral Conjoint Therapy for PTSD (n = 15; CBCT; [Monson, C. M., & Fredman, S. J. (2012). Cognitive-behavioral conjoint therapy for posttraumatic stress disorder: Harnessing the healing power of relationships. Guilford]), a trauma-focused couple therapy, or Prolonged Exposure (n = 17; PE; [Foa, E. B., Hembree, E. A., Dancu, C. V., Peterson, A. L., Cigrang, J. A., & Riggs, D. S. (2008). Prolonged exposure treatment for combat-related stress disorders – provider’s treatment manual [unpublished]. Department of Psychiatry, University of Pennsylvania]), a front-line evidence-based individual treatment for PTSD.Results: There were significant challenges with recruitment and a significant difference in dropout from treatment for the two therapies (65% for PE; 27% for CBCT). Treatment dropout was differentially related to pre-treatment relationship functioning; those with below average relationship functioning had higher dropout in PE compared with CBCT, whereas those with above average relationship functioning did not show differential dropout. In general, CBCT led to relational improvements, but this was not consistently found in PE. Clinician- and self-reported PTSD symptoms improved with both treatments.Conclusions: This study is the first to test a couple or family therapy against a well-established, front-line recommended treatment for PTSD, with expected superiority of CBCT over PE on relationship outcomes. Lessons learned in trial design, including considerations of equipoise, and the effects of differential dropout on trial analyses are discussed. This trial provides further support for the efficacy of CBCT in the treatment of PTSD and enhancement of intimate relationships.
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- 2024
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9. Nerve injury associated with shoulder surgery
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Alexander O. Tuturov, Armenak S. Petrosyan, Mikhail A. Panin, Boris I. Zakharyan, and Omar Al-Bavarid
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shoulder joint ,nerve surgery ,nerve injury ,arthroscopy ,arthroplasty ,Orthopedic surgery ,RD701-811 - Abstract
Introduction Progress in shoulder surgery is associated with improved operating rooms equipment, advanced surgical products and minimally invasive techniques. There are rare injuries to nerves and vessels being intersected or pulled into the sutures. However, marginal tears, compression and nerve entrapment of trunks during access retraction, catheterization, inadequate correct of the patient on the operating table and errors in rehabilitation can be common. The purpose was to identify factors predisposing to peripheral nerve injury to the upper limb during shoulder surgery and offer prevention options. Material and methods Major studies in the field of shoulder anatomy and surgery published between 1984 and 2023 were reviewed to identify anatomical, biomechanical and perioperative factors leading to peripheral nerve injuries. The original literature search was conducted on key resources including GoogleScholar, PubMed, ScienceDirect, RSCI, Scopus. Four approaches were used for structuring and informative presentation of the data to include types of the peripheral nerve injury in the upper limb. Results and discussion Factors predisposing to the peripheral nerve injury in the upper limb during shoulder surgery were identified in the review. Prevention measures include the patient positioned on the operating table with adequate fixation of the head and torso, regardless of the chosen position; traction of the involved upper limb with a load of not greater than 9 kg using a specialized clamp; preoperative marks of the surgical field and staining of bone landmarks; the arthroscopic ports 1–2 cm to be shifted more distally minimizing the fluid flow into the joint during a long operation. Postoperative consultation with rehabilitation specialists is essential to develop an early activation program and assess the risks of neurological disorders. Conclusion The shoulder anatomy and the localization of unsafe zones of the shoulder, the risks associated with a particular manipulation were explored for effective preoperative planning and prevention of neurological complications in the treatment of surgical pathology of the shoulder joint.
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- 2024
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10. Collective chiroptical activity through the interplay of excitonic and charge-transfer effects in localized plasmonic fields
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Huacheng Li, Xin Xu, Rongcheng Guan, Artur Movsesyan, Zhenni Lu, Qiliang Xu, Ziyun Jiang, Yurong Yang, Majid Khan, Jin Wen, Hongwei Wu, Santiago de la Moya, Gil Markovich, Huatian Hu, Zhiming Wang, Qiang Guo, Tao Yi, Alexander O. Govorov, Zhiyong Tang, and Xiang Lan
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Science - Abstract
Abstract The collective light-matter interaction of chiral supramolecular aggregates or molecular ensembles with confined light fields remains a mystery beyond the current theoretical description. Here, we programmably and accurately build models of chiral plasmonic complexes, aiming to uncover the entangled effects of excitonic correlations, intra- and intermolecular charge transfer, and localized surface plasmon resonances. The intricate interplay of multiple chirality origins has proven to be strongly dependent on the site-specificity of chiral molecules on plasmonic nanoparticle surfaces spanning the nanometer to sub-nanometer scale. This dependence is manifested as a distinct circular dichroism response that varies in spectral asymmetry/splitting, signal intensity, and internal ratio of intensity. The inhomogeneity of the surface-localized plasmonic field is revealed to affect excitonic and charge-transfer mixed intermolecular couplings, which are inherent to chirality generation and amplification. Our findings contribute to the development of hybrid classical-quantum theoretical frameworks and the harnessing of spin-charge transport for emergent applications.
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- 2024
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11. Railway Freight Car Model Aerodynamics at Different Airflow Attack Angles
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Alexander O. Shimanovsky and Volha U. Dzemyanchuk
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aerodynamics ,airstream flow ,computer modeling ,aerodynamic coefficient ,Mechanical engineering and machinery ,TJ1-1570 - Abstract
The problem solution is considered for an airstream flow around a rectangular parallelepiped railway car model. The results of computer modeling in ANSYS CFX software system of air flow aerodynamics at its deviation from the longitudinal axis of the car are given. The k-ε turbulence model is used to close the Navier–Stokes equations averaged by Reynolds. The distribution diagrams of the flow velocities and pressures on the frontal and side surfaces of the vehicle are obtained. The values of aerodynamic drag coefficients of the car depending on the attack angle are determined. It is shown that when the attack angle increases from 0 to 10°, the aerodynamic coefficient changes nonlinearly, and this increase corresponds to the experimental values. The developed numerical modeling technique makes it possible to analyze the airflow around both railways rolling stock and automobiles.
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- 2024
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12. Features of mental regulation of schoolchildren cognitive states depending on the level of stress situation
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Alexander O. Prokhorov, Marina E. Valiullina, and Mark G. Yusupov
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cognitive states ,self-regulation ,meaning ,reflection ,self-attitude ,regulatory means ,Psychology ,BF1-990 - Abstract
Background. The relevance of the study is due to insufficient knowledge of the influence of the structures of consciousness on the self-regulation of cognitive states in various stressful situations. The author's concept of mental regulation of psychological states served as a theoretical basis for empirical research. Objective. To identify the features of the relationship between indicators of mental regulation and the frequency of experiencing cognitive states in four situations with different stress levels. Study Participants. The study sample consisted of 70 schoolchildren (31 boys and 29 girls, Mage = 17.7 years) from secondary education schools. Methods. The study implemented the author’s questionnaires “Assessment of the frequency of experiencing mental states” and “Methods of self-regulation of mental states” (M.E. Valiullina). In the instructions, the respondents were presented with four types of situations characterized by different stress levels — from the weak level with a neutral context to the strong level with a negative emotional background. Apart from that, the study participants were tested by means of well-known psychological questionnaires: “Method for Studying the System of Life Meanings” (V.Yu. Kotlyakov), “Self-attitude Questionnaire” (S.R. Pantileev), “Method for Diagnosing Reflexivity” (A.V. Karpov, V.V. Ponomareva). Statistical data processing was carried out using frequency analysis and nonlinear correlation analysis according to Spearman. Results. The data analysis demonstrated: as the tension in the situation increases, the frequency of experiencing productive cognitive states decreases, the probability of unproductive states increases, and the number of applied regulation methods increases as well. Besides, as the tension in the situation increases, the involvement of the consciousness components (those of semantic sphere, reflection, and self-attitude) in the mental regulation of cognitive states increases, the degree of relationships integration increases, and the structure-forming indicators are highlighted. Conclusions. The results obtained show that the level of stress in the situation significantly influences the qualitative composition of the characteristics involved in the systems “mental regulation — cognitive state — regulation method” and “mental regulation — regulation method — cognitive state”
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- 2024
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13. The Autophagic and Apoptotic Death of Forebrain Neurons of Rats with Global Brain Ischemia Is Diminished by the Intranasal Administration of Insulin: Possible Mechanism of Its Action
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Irina O. Zakharova, Liubov V. Bayunova, Daria K. Avrova, Alina D. Tretyakova, Alexander O. Shpakov, and Natalia F. Avrova
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forebrain ischemia ,intranasal insulin ,autophagy ,apoptosis ,neuronal viability ,protein kinases ,Biology (General) ,QH301-705.5 - Abstract
Insulin is a promising neuroprotector. To better understand the mechanism of insulin action, it was important to show its ability to diminish autophagic neuronal death in animals with brain ischemic and reperfusion injury. In forebrain ischemia and reperfusion, the number of live neurons in the hippocampal CA1 region and frontal cortex of rats decreased to a large extent. Intracerebroventricular administration of the autophagy and apoptosis inhibitors to ischemic rats significantly increased the number of live neurons and showed that the main part of neurons died from autophagy and apoptosis. Intranasal administration of 0.5 IU of insulin per rat (before ischemia and daily during reperfusion) increased the number of live neurons in the hippocampal CA1 region and frontal brain cortex. In addition, insulin significantly diminished the level of autophagic marker LC3B-II in these forebrain regions, which markedly increased during ischemia and reperfusion. Our studies demonstrated for the first time the ability of insulin to decrease autophagic neuronal death, caused by brain ischemia and reperfusion. Insulin administered intranasally activated the Akt-kinase (activating the mTORC1 complex, which inhibits autophagy) and inhibited the AMP-activated protein kinase (which activates autophagy) in the hippocampus and frontal cortex of rats with brain ischemia and reperfusion.
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- 2024
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14. We Have Spent Time, Money, and Effort Making Self-Help Digital Mental Health Interventions: Is Anyone Going to Come to the Party?
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Skye Fitzpatrick, Alexander O Crenshaw, Victoria Donkin, Alexis Collins, Angela Xiang, Elizabeth A Earle, Kamya Goenka, Sonya Varma, Julianne Bushe, Tara McFadden, Andrea Librado, and Candice Monson
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Computer applications to medicine. Medical informatics ,R858-859.7 ,Public aspects of medicine ,RA1-1270 - Abstract
Although efficacious psychotherapies exist, a limited number of mental health care providers and significant demand make their accessibility a fundamental problem. Clinical researchers, funders, and investors alike have converged on self-help digital mental health interventions (self-help DMHIs) as a low-cost, low-burden, and broadly scalable solution to the global mental health burden. Consequently, exorbitant financial and time-based resources have been invested in developing, testing, and disseminating these interventions. However, the public’s assumed desirability for self-help DMHIs by experts has largely proceeded without question. This commentary critically evaluates whether self-help DMHIs can, and will, reach their purported potential as a solution to the public burden of mental illness, with an emphasis on evaluating their real-world desirability. Our review finds that self-help DMHIs are often perceived as less desirable and credible than in-person treatments, with lower usage rates and, perhaps accordingly, clinical trials testing self-help DMHIs suffering from widespread recruitment challenges. We highlight two fundamental challenges that may be interfering with the desirability of, and engagement in, self-help DMHIs: (1) difficulty competing with technology companies that have advantages in resources, marketing, and user experience design (but may not be delivering evidence-based interventions) and (2) difficulty retaining (vs initially attracting) users. We discuss a range of potential solutions, including highlighting self-help DMHIs in public mental health awareness campaigns; public education about evidence-based interventions that can guide consumers to appropriate self-help DMHI selection; increased financial and expert support to clinical researchers for marketing, design, and user experience in self-help DMHI development; increased involvement of stakeholders in the design of self-help DMHIs; and investing in more research on ways to improve retention (versus initial engagement). We suggest that, through these efforts, self-help DMHIs may fully realize their promise for reducing the global burden of mental illness.
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- 2024
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15. Diversity and sustainability of bird communities in the Irtysh River valley (the Tyumen Oblast, Russia)
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Maria Yu. Ivanova, Sergey N. Gashev, Polina E. Pokazanieva, Ilya P. Klimshin, Nadezhda G. Bogomyakova, Sergey A. Bayanov, Alexander O. Ivanov, and Sergey S. Tupitsyn
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uvat region ,floodplain of the river irtysh ,species composition ,biodiversity and stability of bird communities ,rare and protected bird species ,Biology (General) ,QH301-705.5 - Abstract
This study investigates the avifauna of the Irtysh floodplain from June 1 to September 1, 2022–2023, revealing a rich diversity of 117 bird species across 14 groups. A notable discovery was the first documented nesting of the blackbird Turdus merula in the Uvat region. Additionally, the presence of 11 rare and declining bird species, as listed in the Red List of the Russian Federation and the Tyumen Oblast, was confirmed. The research delves into the ecological and faunal characteristics of bird communities within the key biotopes of the Uvat region, analyzing species composition, total bird population, diversity indices, and community stability. The findings indicated a direct correlation between these parameters and the heterogeneity of plant cover, spatial distribution, and food availability in critical habitats. Despite various anthropogenic activities like habitat fragmentation, tree and shrub cutting, burning, oil field operations, and recreational pursuits observed in the surveyed areas of the Irtysh floodplain, the overall stability of the bird community remained intact.
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- 2024
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16. FEATURES OF THE FORMATION OF FATTY LIVER DEGENERATION IN CHRONIC EXPOSURE TO TOXIC FIRE PRODUCTS IN FIREFIGHTERS
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Vera Yu. Gatsura, Larisa E. Deryagina, Elena G. Sukhoterina, Vladimir L. Reinyuk, Alexander O. Pyatibrat, and Elena D. Pyatibrat
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fire toxic products ,dioxins ,microbiota ,dysbiosis ,immune status ,fatty liver degeneration ,pathogenesis ,firefighters ,Agriculture ,Science - Abstract
Background. The profession of firefighters is characterized by the impact of a number of dangerous factors, including toxic fire products, which is currently not taken into account by the medical service and medical and psychological support units. To increase the effectiveness of measures aimed at preventing non-communicable diseases, protecting the health and improving the professional longevity of firefighters, it is necessary to take into account the influence of harmful professional factors that influence the formation of various pathologies. Intention of the study: to determine laboratory parameters characterizing the toxic etiology of the formation of fatty liver degeneration in firefighters. Methodology. To determine the features of the pathogenesis of non-alcoholic fatty liver disease, 246 male patients suffering and not suffering from fatty liver degeneration were examined. The tasks were solved by analyzing the results obtained using toxicological, biochemical, and immunological techniques. Results and Discussion. Laboratory markers of fatty liver degeneration have been determined. The peculiarities of the regulation of the immune system in employees of the GPS FPS of the Ministry of Emergency Situations of Russia suffering from fatty liver degeneration have been revealed. Conclusions. Multidirectional changes in instrumental, biochemical and immunological parameters were revealed in firefighters suffering from fatty liver degeneration compared to the control group with the same pathology, indicating the peculiarities of homeostasis disorders, which determines the difference in pathogenesis caused by chronic toxic damage by fire products.
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- 2024
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17. Supporting Human and Machine Co-Learning in Citizen Science: Lessons From Gravity Spy
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Carsten Østerlund, Kevin Crowston, Corey B. Jackson, Yunan Wu, Alexander O. Smith, and Aggelos K. Katsaggelos
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learning ,zone of proximal development ,human-artificial intelligence augmentation ,Science - Abstract
We explore the bi-directional relationship between human and machine learning in citizen science. Theoretically, the study draws on the zone of proximal development (ZPD) concept, which allows us to describe AI augmentation of human learning, human augmentation of machine learning, and how tasks can be designed to facilitate co-learning. The study takes a design-science approach to explore the design, deployment, and evaluations of the Gravity Spy citizen science project. The findings highlight the challenges and opportunities of co-learning, where both humans and machines contribute to each other’s learning and capabilities. The study takes its point of departure in the literature on co-learning and develops a framework for designing projects where humans and machines mutually enhance each other’s learning. The research contributes to the existing literature by developing a dynamic approach to human-AI augmentation, by emphasizing that the ZPD supports ongoing learning for volunteers and keeps machine learning aligned with evolving data. The approach offers potential benefits for project scalability, participant engagement, and automation considerations while acknowledging the importance of tutorials, community access, and expert involvement in supporting learning.
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- 2024
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18. Thrombectomy outcomes for acute ischemic stroke in lower-middle income countries: A systematic review and analysis
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Jaims Lim, Alexander O. Aguirre, Abbas Rattani, Ammad A. Baig, Andre Monteiro, Cathleen C. Kuo, Manhal Siddiqi, Justin Im, Steven B. Housley, Matthew J. McPheeters, Shiau-Sing K. Ciecierska, Vinay Jaikumar, Kunal Vakharia, Jason M. Davies, Kenneth V. Snyder, Elad I. Levy, and Adnan H. Siddiqui
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Disparity ,Global ,Ischemic stroke ,Lower-middle income ,Stroke ,Thrombectomy ,Surgery ,RD1-811 ,Neurology. Diseases of the nervous system ,RC346-429 - Published
- 2024
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19. Effect of jet ejector geometry on the supply of a pumping unit preventing wax-deposit
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Kamil R. Urazakov, Tatiana G. Makarova, and Alexander O. Borisov
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jet pump ,dosing pump ,electric centrifugal pump ,asphalt-resin-paraffin deposits ,wax-deposits inhibitor ,reagent consumption ,Engineering geology. Rock mechanics. Soil mechanics. Underground construction ,TA703-712 - Abstract
Relevance. Today oil production by installations of electric centrifugal pumps is one of the leading methods of mechanized oil production. The mechanized operation of hard-to-recover oil objects is complicated by the high viscosity of reservoir oil, the formation of wax-deposits in the wellbore. This leads to an increase in hydraulic resistances due to a decrease in the flow section of pipes and other pumping equipment components, a decrease in the productivity of wells and the efficiency of pumping production. In this regard, an urgent task is to develop and improve methods and devices for preventing deposits of wax-deposits in wells. Object. Downhole pumping unit for dosing reagent (inhibitor of wax-deposits) into the well, which is a combination of two technical devices – a pump dosing the reagent and a jet pump. Aim. To analyze the influence of the design parameters of the dosing unit on the efficiency of its operation (reagent consumption, liquid cavitation coefficient in the jet pump). Methods. Mathematical modeling of the operation of a downhole dosing unit for the supply of reagent, based on the application of the laws of conservation of mass and quantity of motion, as well as Bernoulli's law for a moving flow in a jet pump. Results. Based on the simulation results, the nature of the influence of the design parameters of the developed installation on the reagent consumption is established. It is established that the maximum flow rate of the reagent is achieved with a mixing chamber diameter of about 22 mm; an increase in diameter relative to the specified value leads to a decrease in the degree of local pressure reduction, a decrease in the diameter of the mixing chamber – a drop in flow due to an increase in the flow rate in the chamber and an increase in hydraulic resistance. It was found that an increase in the supply of electric centrifugal pumps in the considered range of 100–200 m3 per day has practically no effect on the reagent consumption when the mixing chamber diameter is more than 30 mm. It was found that at confuser length values exceeding 210 mm, the cavitation coefficient, regardless of the mixing chamber diameter, exceeds one, which indicates a smooth and uniform pressure reduction in the device body. In general, it is shown that by regulating the design parameters of a downhole metering unit, it is possible to ensure the required reagent consumption at a known electric centrifugal pump supply (well flow rate).
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- 2024
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20. Emergence of a Low-Energy Peak in the Smoothed Absolute Value Circular Dichroism Spectra of Small Helical Gold Nanorods
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Harold P. Hodgins, Jonathan J. Foley, Alexander O. Govorov, Stephen K. Gray, and Ian P. Hamilton
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Chemistry ,QD1-999 - Published
- 2024
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21. Single-cell analysis of immune and stroma cell remodeling in clear cell renal cell carcinoma primary tumors and bone metastatic lesions
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Shenglin Mei, Adele M. Alchahin, Ioanna Tsea, Youmna Kfoury, Taghreed Hirz, Nathan Elias Jeffries, Ting Zhao, Yanxin Xu, Hanyu Zhang, Hirak Sarkar, Shulin Wu, Alexander O. Subtelny, John Inge Johnsen, Yida Zhang, Keyan Salari, Chin-Lee Wu, Mark A. Randolph, David T. Scadden, Douglas M. Dahl, John Shin, Peter V. Kharchenko, Philip J. Saylor, David B. Sykes, and Ninib Baryawno
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Medicine ,Genetics ,QH426-470 - Abstract
Abstract Background Despite therapeutic advances, once a cancer has metastasized to the bone, it represents a highly morbid and lethal disease. One third of patients with advanced clear cell renal cell carcinoma (ccRCC) present with bone metastasis at the time of diagnosis. However, the bone metastatic niche in humans, including the immune and stromal microenvironments, has not been well-defined, hindering progress towards identification of therapeutic targets. Methods We collected fresh patient samples and performed single-cell transcriptomic profiling of solid metastatic tissue (Bone Met), liquid bone marrow at the vertebral level of spinal cord compression (Involved), and liquid bone marrow from a different vertebral body distant from the tumor site but within the surgical field (Distal), as well as bone marrow from patients undergoing hip replacement surgery (Benign). In addition, we incorporated single-cell data from primary ccRCC tumors (ccRCC Primary) for comparative analysis. Results The bone marrow of metastatic patients is immune-suppressive, featuring increased, exhausted CD8 + cytotoxic T cells, T regulatory cells, and tumor-associated macrophages (TAM) with distinct transcriptional states in metastatic lesions. Bone marrow stroma from tumor samples demonstrated a tumor-associated mesenchymal stromal cell population (TA-MSC) that appears to be supportive of epithelial-to mesenchymal transition (EMT), bone remodeling, and a cancer-associated fibroblast (CAFs) phenotype. This stromal subset is associated with poor progression-free and overall survival and also markedly upregulates bone remodeling through the dysregulation of RANK/RANKL/OPG signaling activity in bone cells, ultimately leading to bone resorption. Conclusions These results provide a comprehensive analysis of the bone marrow niche in the setting of human metastatic cancer and highlight potential therapeutic targets for both cell populations and communication channels.
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- 2024
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22. Ammonium Dinitramide as a Prospective N–NO2 Synthon: Electrochemical Synthesis of Nitro-NNO-Azoxy Compounds from Nitrosoarenes
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Alexander S. Budnikov, Nikita E. Leonov, Michael S. Klenov, Mikhail I. Shevchenko, Tatiana Y. Dvinyaninova, Igor B. Krylov, Aleksandr M. Churakov, Ivan V. Fedyanin, Vladimir A. Tartakovsky, and Alexander O. Terent’ev
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electrochemistry ,N–N coupling ,azoxy compounds ,ammonium dinitramide ,nitroso compounds ,antifungal agents ,Organic chemistry ,QD241-441 - Abstract
In this study, the electrochemical coupling of nitrosoarenes with ammonium dinitramide is discovered, leading to the facile construction of the nitro-NNO-azoxy group, which represents an important motif in the design of energetic materials. Compared to known approaches to nitro-NNO-azoxy compounds involving two chemical steps (formation of azoxy group containing a leaving group and its nitration) and demanding expensive, corrosive, and hygroscopic nitronium salts, the presented electrochemical method consists of a single step and is based solely on nitrosoarenes and ammonium dinitramide. The dinitramide salt plays the roles of both the electrolyte and reactant for the coupling. Despite the fact that many side reactions can be expected due to the redox-activity of both the reagents and target products, under optimized conditions the synthesis is performed in an undivided cell under constant current conditions with high current density and can be easily scaled up without a reduction in the product yield. Moreover, the synthesized nitro-NNO-azoxy compounds are discovered to be potent fungicides active against a broad range of phytopathogenic fungi.
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- 2024
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23. The Relationship Between Astronomical and Developmental Times Emerging in Modeling the Evolution of Agents
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Alexander O. Gusev and Leonid M. Martyushev
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Darwinian selection ,entropy production ,time ,evolutionary computation ,i8080 processor ,Science ,Astrophysics ,QB460-466 ,Physics ,QC1-999 - Abstract
The simplest evolutionary model for catching prey by an agent (predator) is considered. The simulation is performed on the basis of a software-emulated Intel i8080 processor. Maximizing the number of catches is chosen as the objective function. This function is associated with energy dissipation and developmental time. It is shown that during Darwinian evolution, agents with an initially a random set of processor commands subsequently acquire a successful catching skill. It is found that in the process of evolution, a logarithmic relationship between astronomical and developmental times arises in agents. This result is important for the ideas available in the literature about the close connection of such concepts as time, Darwinian selection, and the maximization of entropy production.
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- 2024
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24. IMPLEMENTATION OF ENHANCED RECOVERY AFTER SURGERY (ERAS) IN PATIENTS WITH COLORECTAL CANCER AND CONCOMITANT METABOLIC SYNDROME
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Ivan M. Todurov, Oleksandr I. Plehutsa, Oleksandr V. Perekhrestenko, Sergey V. Kosiukhno, Alexander O. Kalashnikov, Artem V. Trots, Valentyn O. Kyryk, and Andrii A. Hrynevych
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colorectal surgery ,colorectal cancer ,metabolic syndrome ,enhanced recovery after surgery protocols ,eras ,early postoperative recovery ,Medicine - Abstract
Introduction. Implementation of enhanced recovery after surgery protocol (ERAS) is becoming more and more widespread due to their effectiveness and safety. At the same time, there is a rather limited number of studies focusing on the opportunities of ERAS in the context of its association with metabolic syndrome in patients with colorectal cancer. This study represents the results of our early experience implementing elements of the ERAS program in the perioperative management of patients with colorectal cancer associated with metabolic syndrome. The aim. To conduct a comparative analysis and evaluate the results of surgical treatment using the enhanced recovery after surgery protocol in patients with colorectal cancer and accompanying metabolic syndrome. Materials and methods. This study included 106 patients with colorectal cancer and accompanying metabolic syndrome, divided into two groups: the first group with the use of elements of the ERAS protocol in colorectal surgery from 2018 – 56 patients, and the second group in which the principles of ERAS were not used (50 patients). Results. In the first group, with a statistically significant difference, a less severe pain syndrome was observed according to VAS (p
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- 2023
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25. Diversity of RNA viruses in the cosmopolitan monoxenous trypanosomatid Leptomonas pyrrhocoris
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Diego H. Macedo, Danyil Grybchuk, Jana Režnarová, Jan Votýpka, Donnamae Klocek, Tatiana Yurchenko, Jan Ševčík, Alice Magri, Michaela Urda Dolinská, Kristína Záhonová, Julius Lukeš, Elena Servienė, Alexandra Jászayová, Saulius Serva, Marina N. Malysheva, Alexander O. Frolov, Vyacheslav Yurchenko, and Alexei Yu. Kostygov
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Tombus-like viruses ,Ostravirus ,Leishbuviridae ,Qinviridae ,Pyrrhocoris apterus ,Biology (General) ,QH301-705.5 - Abstract
Abstract Background Trypanosomatids are parasitic flagellates well known because of some representatives infecting humans, domestic animals, and cultural plants. Many trypanosomatid species bear RNA viruses, which, in the case of human pathogens Leishmania spp., influence the course of the disease. One of the close relatives of leishmaniae, Leptomonas pyrrhocoris, has been previously shown to harbor viruses of the groups not documented in other trypanosomatids. At the same time, this species has a worldwide distribution and high prevalence in the natural populations of its cosmopolitan firebug host. It therefore represents an attractive model to study the diversity of RNA viruses. Results We surveyed 106 axenic cultures of L. pyrrhocoris and found that 64 (60%) of these displayed 2–12 double-stranded RNA fragments. The analysis of next-generation sequencing data revealed four viral groups with seven species, of which up to five were simultaneously detected in a single trypanosomatid isolate. Only two of these species, a tombus-like virus and an Ostravirus, were earlier documented in L. pyrrhocoris. In addition, there were four new species of Leishbuviridae, the family encompassing trypanosomatid-specific viruses, and a new species of Qinviridae, the family previously known only from metatranscriptomes of invertebrates. Currently, this is the only qinvirus with an unambiguously determined host. Our phylogenetic inferences suggest reassortment in the tombus-like virus owing to the interaction of different trypanosomatid strains. Two of the new Leishbuviridae members branch early on the phylogenetic tree of this family and display intermediate stages of genomic segment reduction between insect Phenuiviridae and crown Leishbuviridae. Conclusions The unprecedented wide range of viruses in one protist species and the simultaneous presence of up to five viral species in a single Leptomonas pyrrhocoris isolate indicate the uniqueness of this flagellate. This is likely determined by the peculiarity of its firebug host, a highly abundant cosmopolitan species with several habits ensuring wide distribution and profuseness of L. pyrrhocoris, as well as its exposure to a wider spectrum of viruses compared to other trypanosomatids combined with a limited ability to transmit these viruses to its relatives. Thus, L. pyrrhocoris represents a suitable model to study the adoption of new viruses and their relationships with a protist host.
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- 2023
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26. Predictors of lower exercise capacity in patients with cancer
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Ruben Evertz, Christine Diehl, Katharina Gödde, Miroslava Valentova, Tania Garfias-Veitl, Tobias R. Overbeck, Friederike Braulke, Alessia Lena, Sara Hadzibegovic, Annalen Bleckmann, Ulrich Keller, Ulf Landmesser, Alexander O. König, Gerd Hasenfuss, Andreas Schuster, Markus S. Anker, and Stephan von Haehling
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Medicine ,Science - Abstract
Abstract Maintaining cancer patients’ exercise capacity and therefore patients’ ability to live a self-determined life is of huge importance, but little is known about major determinants. We sought to identify determinants of exercise capacity in patients with a broad spectrum of cancer types, who were already receiving cancer treatment or about to commence such therapy. Exercise capacity was assessed in 253 consecutive patients mostly suffering from advanced cancer using the 6-min walk test (6-MWT). All patients underwent echocardiography, physical examination, resting electrocardiogram, hand grip strength (HGS) measurement, and laboratory assessments. Patients were divided into two groups according to the median distance in the 6-MWT (459 m). Patients with lower exercise capacity were older, had significantly lower HGS and haemoglobin and higher values of high sensitive (hs) Troponin T and NT-proBNP (all p 0.2). Using multivariable logistic regression, we found that the presence of anaemia (odds ratio (OR) 6.172, 95% confidence interval (CI) 1.401–27.201, p = 0.016) as well as an increase in hs Troponin T (OR 3.077, 95% CI 1.202–5.301, p = 0.019) remained independent predictors of impaired exercise capacity. Increasing HGS was associated with a reduced risk of a lower exercise capacity (OR 0.896, 95% CI 0.813–0.987, p = 0.026). Screening patients for elevated hs troponin levels as well as reduced HGS may help to identify patients at risk of lower exercise capacity during cancer treatment.
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- 2023
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27. Curating Virality: Exploring Curated Logics Within #BlackLivesMatter on Twitter/X
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Yiran Duan, Jeff Hemsley, Alexander O. Smith, Una Joh, LaVerne Gray, and Christy Khoury
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Communication. Mass media ,P87-96 - Abstract
This study examines what types of messages users posted and spread about #Black/Blue/AllLivesMatter during the Black History Month of 2022. Using both qualitative and quantitative methods, about one million tweets were analyzed to test if different levels of opinion leaders tend to spread different kinds of messages related to the context. Using the curation logic of Thorson and Well and Lakoff’s semantic theory as theoretical lenses, we offer some observations about the differences in logics (incentives and norms) that opinion leaders in our dataset might face. We find that different levels of opinion leaders shared different types of messages. The implications of this study call for strategies that foster meaningful discussions on social movements amid polarized views. The study also advocates for refining platform design to encourage the dissemination of factual information over contentious arguments and reaching a societal consensus on critical social issues, such as racial inequality and police brutality. This research contributes to updating the theory of curation logics, virality, and opinion leaders, as well as provides empirical data for the discussions of the #BlackLivesMatter social movement and its related discussions of #AllLivesMatter and #BlueLivesMatter.
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- 2024
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28. CO2 capture and in-situ conversion to organic molecules
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Lan Zhao, Hai-Yang Hu, An-Guo Wu, Alexander O. Terent’ev, Liang-Nian He, and Hong-Ru Li
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CO2 utilization ,CO2 adducts ,In-situ conversion ,Thermocatalysis ,Green chemistry ,Technology - Abstract
To address the CO2 accumulation in atmosphere, various initiatives have been proposed, among which CO2 capture and utilization (CCU) is regarded as an appealing strategy to reconcile carbon emission and resource utilization. Especially, integrated CO2 capture and utilization (ICCU), i.e. performing CO2 capture and in-situ conversion can circumvent the energy-intensive CO2 desorption step and thus facilitate establishing step- and energy-efficient process, rendering the conversion at mild conditions particularly at low pressure due to substantial activation upon CO2 uptake. However, CO2 capture and in-situ conversion is not the simple add-up of these two processes. Its successful implementation relies on the harmonization of CO2 capture reagents, substrates and the corresponding catalysts. By far, tremendous efforts have been made in this field and a plethora of CO2 capture reagents including inorganic bases, organic bases, ionic liquids and carbonaceous materials have been utilized to capture CO2 and the conversion protocols such as hydrogenation, cycloaddition, carboxylative cyclization etc. have been explored for these captured CO2. As a result, the valuable products containing methanol, methane, carbonates, carbamates, oxazolidinones, ureas, and quinazolinone have been obtained from CO2 and more importantly, the CO2 chemistry theory is also enriched via investigating the structure and reactivity of the captured CO2 in various reactions. In this review, we summarize the progress on CO2 capture and in-situ conversion based on the reaction types and corresponding CO2 absorbents. It’s hoped that this review can shed light on the design of CO2 capture and in-situ conversion and inspire the further development of this field.
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- 2024
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29. Microbiome markers in HPV-positive and HPV-negative women of reproductive age with ASCUS and SIL determined by V4 region of 16S rRNA gene sequencing
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Anastasiya Peremykina, Valery Cheranev, Andrey Krivoy, Alexander O. Andreev, Zhanna Repinskaia, Aleksandra V. Asaturova, Dmitriy Korostin, Denis Rebrikov, and Gyuldana R. Bayramova
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squamous intraepithelial lesion ,16S rRNA gene sequencing ,HPV ,cervicovaginal microbiota ,SIL prediction ,Microbiology ,QR1-502 - Abstract
IntroductionHuman papilloma virus (HPV) is the most common sexually transmitted infection worldwide. Cervicovaginal microbiota plays an important role in HPV infection and is associated with the development of squamous intraepithelial lesions (SIL). The natural history of cervical cancer involves reversible changes in the cervical tissue from a normal state, in which no neoplastic changes are detected in the squamous epithelium, to varying states of cellular abnormalities that ultimately lead to cervical cancer. Low-grade SIL (LSIL), like another cytological category - atypical squamous cells of undetermined significance (ASCUS), may progress to high-grade SIL (HSIL) and invasive cervical cancer or may regress to a normal state.MethodsIn this work, we studied cervical canal microbiome in 165 HPV-positive and HPV-negative women of a reproductive age with ASCUS [HPV(+) n = 29; HPV(−) n = 11], LSIL [HPV(+) n = 32; HPV(−) n = 25], HSIL [HPV(+) n = 46], and the control group with negative for intraepithelial lesion malignancy (NILM) [HPV(−) n = 22].Results and DiscussionHPV16 is the most prevalent HPV type. We have not found any differences between diversity in studied groups, but several genus [like Prevotella (p-value = 0.026), Gardnerella (p-value = 0.003), Fannyhessea (p-value = 0.024)] more often occurred in HSIL group compared by NILM or LSIL regardless of HPV. We have found statistically significant difference in occurrence or proportion of bacterial genus in studied groups. We also identified that increasing of the ratio of Lactobacillus iners or age of patient lead to higher chance to HSIL, while increasing of the ratio of Lactobacillus crispatus lead to higher chance to LSIL. Patients with a moderate dysbiosis equally often had either of three types of vaginal microbial communities (CST, Community State Type) with the prevalence of Lactobacillus crispatus (CST I), Lactobacillus gasseri (CST II), and Lactobacillus iners (CST III); whereas severe dysbiosis is linked with CST IV involving the microorganisms genera associated with bacterial vaginosis and aerobic vaginitis: Gardnerella, Fannyhessea, Dialister, Sneathia, Anaerococcus, Megasphaera, Prevotella, Finegoldia, Peptoniphilus, Porphyromonas, Parvimonas, and Streptococcus.
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- 2024
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30. Development of correction coefficients for cable cross-sections selection in polymeric cable channel
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Alexander O. Shepelev, Dmitry S. Osipov, and Vsevolod A. Tkachenko
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simulation ,cable transmission line ,polyethylene pipe ,long-term permissible current load ,correction factor ,Engineering geology. Rock mechanics. Soil mechanics. Underground construction ,TA703-712 - Abstract
Relevance. The need to develop correction coefficients for selecting cable sections when laying in the polymeric cable channel in the Russian Federation. Currently, there are no recommendations fixed by the state standards for laying cable power lines in polymer pipes. Aim. To develop correction factors for laying cable power lines in the polymer cable channel. Objects. Cable transmission lines laid underground in polymer pipes. Methods. Numerical simulation of combined frequency-stationary method; determination of correction factors based on interpolation of model results; evaluation and analysis of comparison of cables in corrugated and smooth polymer pipes. Results. Calculations of the long-term current load for cables laid in the polymeric cable channel showed the effectiveness of this method of laying cable lines. The use of pipes with smooth walls makes it much more efficient to remove heat from cables into the environment (compared to a corrugated pipe), which allows you to increase the capacity of the same cable by about 25%, depending on the number of pipes laid nearby. Based on the results of the simulation of the thermal mode of corrugated and smooth polymer pipes, it can be concluded that corrugated pipe significantly complicates heat removal from the cable system to the environment (soil). This is due to the presence of air gaps in the ribbed structure of the corrugated pipe. The gaps filled with air act as a heat-insulating layer, unlike a smooth pipe in which this gap is absent. The developed coefficients will take into account the influence of the location of cables on their allowable current already at the design stage, which will reduce the cost of power transmission losses due to the wrong cable cross-section and high temperature.
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- 2024
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31. Shining the spotlight on the neglected: new high-quality genome assemblies as a gateway to understanding the evolution of Trypanosomatidae
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Amanda T. S. Albanaz, Mark Carrington, Alexander O. Frolov, Anna I. Ganyukova, Evgeny S. Gerasimov, Alexei Y. Kostygov, Julius Lukeš, Marina N. Malysheva, Jan Votýpka, Alexandra Zakharova, Kristína Záhonová, Sara L. Zimmer, Vyacheslav Yurchenko, and Anzhelika Butenko
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Trypanosomatids ,Genome assembly ,Whole-genome sequencing ,Monoxenous ,Dixenous ,Parasite ,Biotechnology ,TP248.13-248.65 ,Genetics ,QH426-470 - Abstract
Abstract Background Protists of the family Trypanosomatidae (phylum Euglenozoa) have gained notoriety as parasites affecting humans, domestic animals, and agricultural plants. However, the true extent of the group's diversity spreads far beyond the medically and veterinary relevant species. We address several knowledge gaps in trypanosomatid research by undertaking sequencing, assembly, and analysis of genomes from previously overlooked representatives of this protistan group. Results We assembled genomes for twenty-one trypanosomatid species, with a primary focus on insect parasites and Trypanosoma spp. parasitizing non-human hosts. The assemblies exhibit sizes consistent with previously sequenced trypanosomatid genomes, ranging from approximately 18 Mb for Obscuromonas modryi to 35 Mb for Crithidia brevicula and Zelonia costaricensis. Despite being the smallest, the genome of O. modryi has the highest content of repetitive elements, contributing nearly half of its total size. Conversely, the highest proportion of unique DNA is found in the genomes of Wallacemonas spp., with repeats accounting for less than 8% of the assembly length. The majority of examined species exhibit varying degrees of aneuploidy, with trisomy being the most frequently observed condition after disomy. Conclusions The genome of Obscuromonas modryi represents a very unusual, if not unique, example of evolution driven by two antidromous forces: i) increasing dependence on the host leading to genomic shrinkage and ii) expansion of repeats causing genome enlargement. The observed variation in somy within and between trypanosomatid genera suggests that these flagellates are largely predisposed to aneuploidy and, apparently, exploit it to gain a fitness advantage. High heterogeneity in the genome size, repeat content, and variation in chromosome copy numbers in the newly-sequenced species highlight the remarkable genome plasticity exhibited by trypanosomatid flagellates. These new genome assemblies are a robust foundation for future research on the genetic basis of life cycle changes and adaptation to different hosts in the family Trypanosomatidae.
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- 2023
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32. Cyclic Organic Peroxides as New Fungicides against Phytopathogenic Fungi
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Ivan A. Yaremenko, Peter S. Radulov, Yulia Yu. Belyakova, Dmitrii I. Fomenkov, Vera A. Vil’, Maria A. Kuznetsova, Valentina N. Demidova, Alexei P. Glinushkin, and Alexander O. Terent’ev
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crop protection ,fungicides ,organic peroxides ,Agriculture ,Chemical technology ,TP1-1185 - Abstract
The search for new classes of fungicides has long been important in plant protection due to the development of fungal resistance to currently used agrochemicals. Organic peroxides have long been regarded as exotic and unstable compounds. The discovery of the antimalarial activity of the peroxide natural product Artemisinin, an achievement that was recently recognized with the Nobel Prize, has brought organic peroxides into the medicinal and agrochemistry. In this paper, fungicidal activity of synthesized organic peroxides—geminal bishydroperoxide, bridged 1,2,4,5-tetraoxanes, and tricyclic monoperoxides—were tested in vitro against an important species of phytopathogenic fungi (F. culmorum, R. solani, A. solani, P. infestans, C. coccodes). We discovered that substituted bridged 1,2,4,5-tetraoxanes exhibit fungicidal activity comparable or superior to azoxystrobin and superior to geminal bishydroperoxide and tricyclic monoperoxides. The contact mode of action was demonstrated for the bridged 1,2,4,5-tetraoxane.
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- 2023
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33. Hormonal and Allosteric Regulation of the Luteinizing Hormone/Chorionic Gonadotropin Receptor
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Alexander O. Shpakov
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luteinizing hormone ,human chorionic gonadotropin ,luteinizing hormone/chorionic gonadotropin receptor ,allosteric regulator ,allosteric site ,adenylyl cyclase ,β-arrestin ,biased signaling ,steroidogenesis ,ovulation ,Biochemistry ,QD415-436 ,Biology (General) ,QH301-705.5 - Abstract
Luteinizing hormone (LH) and human chorionic gonadotropin (CG), like follicle-stimulating hormone, are the most important regulators of the reproductive system. They exert their effect on the cell through the LH/CG receptor (LHCGR), which belongs to the family of G protein-coupled receptors. Binding to gonadotropin induces the interaction of LHCGR with various types of heterotrimeric G proteins (Gs, Gq/11, Gi) and β-arrestins, which leads to stimulation (Gs) or inhibition (Gi) of cyclic adenosine monophosphate-dependent cascades, activation of the phospholipase pathway (Gq/11), and also to the formation of signalosomes that mediate the stimulation of mitogen-activated protein kinases (β-arrestins). The efficiency and selectivity of activation of intracellular cascades by different gonadotropins varies, which is due to differences in their interaction with the ligand-binding site of LHCGR. Gonadotropin signaling largely depends on the status of N- and O-glycosylation of LH and CG, on the formation of homo- and heterodimeric receptor complexes, on the cell-specific microenvironment of LHCGR and the presence of autoantibodies to it, and allosteric mechanisms are important in the implementation of these influences, which is due to the multiplicity of allosteric sites in different loci of the LHCGR. The development of low-molecular-weight allosteric regulators of LHCGR with different profiles of pharmacological activity, which can be used in medicine for the correction of reproductive disorders and in assisted reproductive technologies, is promising. These and other issues regarding the hormonal and allosteric regulation of LHCGR are summarized and discussed in this review.
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- 2024
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34. Hippocampome.org 2.0 is a knowledge base enabling data-driven spiking neural network simulations of rodent hippocampal circuits
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Diek W Wheeler, Jeffrey D Kopsick, Nate Sutton, Carolina Tecuatl, Alexander O Komendantov, Kasturi Nadella, and Giorgio A Ascoli
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knowledge base ,hippocampus ,simulation ,open access ,Medicine ,Science ,Biology (General) ,QH301-705.5 - Abstract
Hippocampome.org is a mature open-access knowledge base of the rodent hippocampal formation focusing on neuron types and their properties. Previously, Hippocampome.org v1.0 established a foundational classification system identifying 122 hippocampal neuron types based on their axonal and dendritic morphologies, main neurotransmitter, membrane biophysics, and molecular expression (Wheeler et al., 2015). Releases v1.1 through v1.12 furthered the aggregation of literature-mined data, including among others neuron counts, spiking patterns, synaptic physiology, in vivo firing phases, and connection probabilities. Those additional properties increased the online information content of this public resource over 100-fold, enabling numerous independent discoveries by the scientific community. Hippocampome.org v2.0, introduced here, besides incorporating over 50 new neuron types, now recenters its focus on extending the functionality to build real-scale, biologically detailed, data-driven computational simulations. In all cases, the freely downloadable model parameters are directly linked to the specific peer-reviewed empirical evidence from which they were derived. Possible research applications include quantitative, multiscale analyses of circuit connectivity and spiking neural network simulations of activity dynamics. These advances can help generate precise, experimentally testable hypotheses and shed light on the neural mechanisms underlying associative memory and spatial navigation.
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- 2024
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35. Peroxide derivatives as SARS-CoV-2 entry inhibitors
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Ding-qi Zhang, Qin-hai Ma, Meng-chu Yang, Yulia Yu. Belyakova, Zi-feng Yang, Peter S. Radulov, Rui-hong Chen, Li-jun Yang, Jing-yuan Wei, Yu-tong Peng, Wu-yan Zheng, Ivan A. Yaremenko, Alexander O. Terent'ev, Paolo Coghi, and Vincent Kam Wai Wong
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SARS-CoV-2, peroxide, aminoperoxide derivatives, spike protein ,RBD ,Bio-layer interferometry ,Microbiology ,QR1-502 ,Infectious and parasitic diseases ,RC109-216 - Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of the ongoing coronavirus disease 2019 (COVID-19) pandemic. Host cell invasion is mediated by the interaction of the viral spike protein (S) with human angiotensin-converting enzyme 2 (ACE2) through the receptor-binding domain (RBD). In this work, bio-layer interferometry (BLI) was used to screen a series of fifty-two peroxides, including aminoperoxides and bridged 1,2,4 – trioxolanes (ozonides), with the aim of identifying small molecules that interfere with the RBD-ACE2 interaction. We found that two compounds, compound 21 and 29, exhibit the activity to inhibit RBD-ACE2. They are further demonstrated to inhibit SARS-CoV-2 cell entry, as shown in pseudovirus assay and experiment with authentic SARS-CoV-2. A comprehensive in silico analysis was carried out to study the physicochemical and pharmacokinetic properties, revealing that both compounds have good physicochemical properties as well as good bioavailability. Our results highlight the potential of small molecules targeting RBD inhibitors as potential therapeutic drugs for COVID-19.
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- 2024
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36. An image classification method using hashing preprocessing
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Sergei E Ivanov, Tatiana Victorovna Zudilova, Alexander O Ruban, Igor V Anantchenko, and Lubov N Ivanova
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image classification hashing preprocessing image recognition ,Telecommunication ,TK5101-6720 - Abstract
In the study, the authors consider classical classification methods for the applied problem of image recognition. Accuracy, computation time, classifier size, training time for the following methods are considered: "Fully Connected Neural Network", "Convolutional Neural Network", "Recurrent Neural Network", "Decision Tree", "Gradient Boosted Trees", "Logistic Regression", "Markov", "Naive Bayes", "Nearest Neighbors", "Random Forest", "Support Vector Machine". A new approach "Neural Network with Hash" is proposed, which represents image preprocessing using polynomial hashing. Collision resolution is performed by a fast method of open addressing. A computer experiment on classification by 10 classes was carried out on a dataset of 600 animal images using the Wolfram mathematical package. For the proposed approach with preprocessing, the results showed the same classification accuracy as the classical methods, and a higher training and computational speed than the "Convolutional Neural Network" and "Recurrent Neural Network".
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- 2023
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37. Systematic review of medicinal leech therapy in urology
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Alexander O. Battin, Natalie Hobeika, and Matthew J. Zdilla
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Hirudo medicinalis ,Hirudotherapy ,Leeching ,Systematic review ,Urology ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
Abstract Background Medicinal leech therapy, otherwise known as hirudotherapy or leeching, has been utilized for numerous pathologies over centuries. The technique resurfaced in modern medicine for its beneficial effects in microsurgical complications, particularly venous congestion. Recently, several cases have documented the utilization of medicinal leech therapy for the management of urologic disease states and surgical complications. It is important to understand the past, present, and future possibilities for hirudotherapy in urology. However, a systematic review of medical leech therapy in this context has yet to be conducted. Accordingly, and with an emphasis on salient clinical details, this study aims to systematically review the cases of hirudotherapy applied to urological conditions. Main body of the abstract A systematic review of cases in MEDLINE/PubMed was performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Of 49 search results, 11 articles detailing 13 unique cases of medicinal leech therapy used in the urological context were included. Hirudotherapy was conducted in 10 of 13 cases (76.9%) for the management of congested blood occurring in five cases post-penile replantation, two cases of postoperative scrotal hematoma, two cases of venous congestion of the glans post-neonatal bladder exstrophy repair, and one case of refractory priapism. Leeching in the remaining three cases was for the management of penoscrotal edema in patients with hormone refractory prostate carcinoma treated with radical radiation therapy. All 13 cases (100%) reported clinical improvement from hirudotherapy. Venous congestion/hematoma cases noted decreased displaced blood volume. The patient experiencing priapism reported decreased pain despite the persistence of cavernosal swelling. The three cases of penoscrotal edema reported significant decreases in swelling due to serous fluid drainage from leech puncture sites. No complications or side effects were reported in the nine adult patients. The four postoperative neonatal patients all required blood product throughout treatment. Short conclusion The systematic review of the cases demonstrates that medicinal leech therapy is a favorable treatment option for individuals with varied urological pathologies and that hirudotherapy may improve post-surgical outcomes in the urological setting. Hirudotherapy should be considered as a viable treatment modality in specific venostatic urological conditions.
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- 2023
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38. SIMULATION OF THERMAL PROCESSES IN A SUBMERSIBLE MOTOR OF AN ELECTRIC CENTRIFUGAL PUMP OPERATING IN A PERIODIC MODE
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Kamil R. Urazakov, Mikhail V. Rukin, and Alexander O. Borisov
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electric centrifugal pump installation ,submersible electric motor ,temperature ,simulation ,periodic short-term mode ,submersible electric motor power ,Engineering geology. Rock mechanics. Soil mechanics. Underground construction ,TA703-712 - Abstract
Relevance. Today, one of the important trends in the Russian oil and gas industry is the increase in the fund of low-yield wells, in this regard, the improvement of technologies for mechanized production of low-yield wells is relevant. Installations of electric centrifugal pumps have become widespread in mechanized oil production, however, the operation of low-flow wells by electric centrifugal installations is accompanied by a number of complications, in particular, insufficient heat removal from the submersible engine by the flow in the well. A promising method of increasing the efficiency of electric-centric installations in low-flow wells is the implementation of a periodic short-term pumping mode. Object: thermal processes in the «submersible engine – borehole fluid» system of an electric centrifugal pump installation operating in a periodic short-term mode. The purpose of the research is to study the formation of a temperature field in a submersible electric motor and the fluid flowing around it during operation of an electric centrifugal pump in a periodic short-term mode. Methods: modeling of thermal processes in a well based on the numerical solution of the system of heat transfer equations in the «submersible engine – borehole fluid» system. Results. Based on the simulation results, it is shown that the temperature of the submersible electric motor and the liquid reaches maximum values at the initial stage during the well commissioning, during further operation of the well in a periodic short-term mode, the temperature of the submersible motor and the borehole fluid decreases significantly (the heating of the submersible motor and the liquid relative to the initial temperature decreases by more than 2 times). The influence of the power of the submersible engine (after the output of the well to the mode) on the thermal field in the well was investigated and it was found that with an increase in power, the heating of the submersible engine and the liquid increases in proportion to the degree of growth in power. The influence of the duration of pumping and accumulation periods on the temperature of the submersible engine and liquid (after the well is put into operation) has been studied. It is established that with an increase in the duration of the pumping period, the temperature of the submersible engine and the liquid grows, as a result, from the point of view of reducing the amplitude temperature of the electric centrifugal pump installation nodes in the periodic short-term mode, it is necessary to set the shortest possible periods of pumping and accumulation cycles. The results of numerical calculations are compared with experimental data and it is shown that the proposed model can be used to calculate the thermal regime of a submersible engine during operation of an electric center installation in a periodic short-term mode.
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- 2023
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39. Cardiovascular and metabolic determinants of quality of life in patients with cancer
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Ruben Evertz, Katharina Gödde, Christine Diehl, Miroslava Valentova, Tania Garfias‐Veitl, Friederike Braulke, Gerald G. Wulf, Tobias R. Overbeck, Annalen Bleckmann, Alexander O. König, Pia Weinländer, Sophia Potthoff, Sara Hadzibegovic, Alessia Lena, Ulrich Keller, Ulf Landmesser, Andreas Schuster, Markus S. Anker, Gerd Hasenfuß, and Stephan vonHaehling
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Quality of life ,Cancer ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Aims Maintaining quality of life (QoL) in patients with cancer has gathered significant interest, but little is known about its major determinants. We sought to identify determinants of QoL in patients undergoing cancer treatment as well as in treatment‐naïve patients about to commence such therapy. Methods and results QoL was assessed in 283 patients with cancer using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 questionnaire. All patients underwent a battery of tests including physical examination, resting electrocardiogram, hand grip strength, and biochemistry assessment. Using multivariable logistic regression, we found that age [odds ratio (OR) 0.954, 95% confidence interval (CI) 0.916–0.994], resting heart rate (OR 1.036, 95% CI 1.004–1.068), hand grip strength (OR 0.932, 95% CI 0.878–0.990), and the presence of cachexia (OR 4.334, 95% CI 1.767–10.631) and dyspnoea (OR 3.725, 95% CI 1.540–9.010; all P
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- 2023
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40. Dissecting the immune suppressive human prostate tumor microenvironment via integrated single-cell and spatial transcriptomic analyses
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Taghreed Hirz, Shenglin Mei, Hirak Sarkar, Youmna Kfoury, Shulin Wu, Bronte M. Verhoeven, Alexander O. Subtelny, Dimitar V. Zlatev, Matthew W. Wszolek, Keyan Salari, Evan Murray, Fei Chen, Evan Z. Macosko, Chin-Lee Wu, David T. Scadden, Douglas M. Dahl, Ninib Baryawno, Philip J. Saylor, Peter V. Kharchenko, and David B. Sykes
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Science - Abstract
The immune suppressive tumour microenvironment drives recurrence and metastatic disease in prostate cancer. Here authors provide a detailed analysis of the microenvironment via single cell RNA sequencing and high-resolution spatial transcriptomics to identify tumour-dependent changes compared to healthy tissue.
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- 2023
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41. 4-Disubstituted Pyrazolin-3-Ones—Novel Class of Fungicides against Phytopathogenic Fungi
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Elena R. Lopat’eva, Alexander S. Budnikov, Igor B. Krylov, Anna L. Alekseenko, Alexey I. Ilovaisky, Alexey P. Glinushkin, and Alexander O. Terent’ev
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pyrazolin-3-ones ,fungicidal compounds ,crop protection ,nitropyrazolones ,new modes of action ,Agriculture ,Chemical technology ,TP1-1185 - Abstract
The search for fungicides of novel classes is the long-standing priority in crop protection due to the continuous development of fungal resistance against currently used types of active compounds. Recently, 4-nitropyrazolin-3-ones were discovered as highly potent fungicides, of which activity was believed to be strongly associated with the presence of a nitro group in the pyrazolone ring. In this paper, a series of 4-substituted pyrazolin-3-ones were synthesized and their fungicidal activity against an important species of phytopathogenic fungi (Venturia inaequalis, Rhizoctonia solani, Fusarium oxysporum, Fusarium moniliforme, Bipolaris sorokiniana, and Sclerotinia sclerotiorum) was tested in vitro. We discovered that 4-mono and 4,4-dihalogenated pyrazolin-3-ones demonstrate fungicidal activity comparable to that of 4-nitropyrazolin-3-ones and other modern fungicides (such as kresoxim methyl). This discovery indicates that NO2 moiety can be replaced by other groups of comparable size and electronic properties without the loss of fungicidal activity and significantly expands the scope of potent new fungicides based on a pyrazolin-3-one fragment.
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- 2023
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42. A transcriptional metastatic signature predicts survival in clear cell renal cell carcinoma
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Adele M. Alchahin, Shenglin Mei, Ioanna Tsea, Taghreed Hirz, Youmna Kfoury, Douglas Dahl, Chin-Lee Wu, Alexander O. Subtelny, Shulin Wu, David T. Scadden, John H. Shin, Philip J. Saylor, David B. Sykes, Peter V. Kharchenko, and Ninib Baryawno
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Science - Abstract
Metastatic clear cell renal cell carcinoma has a poor prognosis. Here, the authors use single cell RNA-seq to show a distinct gene expression signature in the primary tumour of metastatic patients, and highlights immune cell receptor interactions as potential therapeutic targets.
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- 2022
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43. Photonic synapses with ultralow energy consumption for artificial visual perception and brain storage
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Caihong Li, Wen Du, Yixuan Huang, Jihua Zou, Lingzhi Luo, Song Sun, Alexander O. Govorov, Jiang Wu, Hongxing Xu, and Zhiming Wang
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mos2 synaptic transistors ,visual perception ,ultralow power consumption ,memory ,Optics. Light ,QC350-467 - Abstract
The human visual system, dependent on retinal cells, can be regarded as a complex combination of optical system and nervous system. Artificial retinal system could mimic the sensing and processing function of human eyes. Optically stimulated synaptic devices could serve as the building blocks for artificial retinas and subsequent information transmission system to brain. Herein, photonic synaptic transistors based on polycrystalline MoS2, which could simulate human visual perception and brain storage, are presented. Moreover, the photodetection range from visible light to near-infrared light of MoS2 multilayer could extend human eyes’ vision limitation to near-infrared light. Additionally, the photonic synaptic transistor shows an ultrafast speed within 5 μs and ultralow power consumption under optical stimuli about 40 aJ, several orders of magnitude lower than biological synapses (50 ms and 10 fJ). Furthermore, the backgate control could act as emotional modulation of the artificial brain to enhance or suppress memory function, i.e. the intensity of photoresponse. The proposed carrier trapping/detrapping as the main working mechanism is presented for the device. In addition, synaptic functionalities including short synaptic plasticity, long synaptic plasticity and paired-pulse facilitation could be successfully simulated based on the prepared device. Furthermore, the large difference between short synaptic plasticity and long synaptic plasticity reveals the better image pre-processing function of the prepared photonic synapses. The classical Pavlovian conditioning associated with the associative learning is successfully implemented as well. Therefore, the efficient and rich functionalities demonstrate the potential of the MoS2 synaptic device that integrates sensing-memory-preprocessing capabilities for realizing artificial neural networks with different emotions that mimic human retina and brain.
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- 2022
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44. 3-(4-Fluorophenyl)-1-(1-(4-fluorophenyl)-3,3,3-trifluoroprop-1-en-1-yl)-5-fluoro-1H-pyrazole
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Stanislav A. Paveliev, Alexander O. Ustyuzhanin, Igor B. Krylov, and Alexander O. Terent’ev
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trifluoromethylation ,photoredox catalysis ,carbon nitride ,pyrazoles ,free radicals ,Inorganic chemistry ,QD146-197 - Abstract
In this work, the title compound was synthesized via the visible-light-induced radical denitrogenative trifluoromethylation of the corresponding vinyl azide followed by Cs2CO3-mediated defluorinative cyclization of the resultant azine. The widely available sodium trifluoromethanesulfinate is used as a precursor of CF3 radicals, while graphitic carbon nitride (g-C3N4) is employed as an environmentally friendly, cheap, and efficient heterogeneous photocatalyst. The structure of the synthesized compound was established by 1H, 13C, 19F-NMR, IR spectroscopy, and mass-spectrometry.
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- 2023
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45. The Mite Steatonyssus periblepharus Is a Novel Potential Vector of the Bat Parasite Trypanosoma dionisii
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Marina N. Malysheva, Anna I. Ganyukova, Alexander O. Frolov, Dmitriy V. Chistyakov, and Alexei Yu. Kostygov
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Chiroptera ,bats ,trypanosome ,18S rRNA gene ,developmental stages ,life cycle ,Biology (General) ,QH301-705.5 - Abstract
Trypanosoma dionisii, for which only bat bugs (Cimicidae) had previously been demonstrated as vectors, was, for the first time, detected in the gamasine mite Steatonyssus periblepharus in Russia. The molecular phylogenetic analysis indicated that trypanosomes found in these mites belong to the “clade A” of T. dionisii, which, based on genetic distances, can be considered as a species separate from the sister clade B, and according to available data also has a distinct geographic distribution. The presence of developmental forms of T. dionisii resembling those previously described during the development of this trypanosome in cimicids suggests that S. periblepharus is a novel vector of the studied trypanosome.
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- 2023
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46. Understanding the dynamics of randomly positioned dipolar spin ensembles
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Timo Gräßer, Kristine Rezai, Alexander O. Sushkov, and Götz S. Uhrig
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Physics ,QC1-999 - Abstract
Dipolar spin ensembles with random spin positions are attracting much attention because they help us to understand decoherence as it occurs in solid-state quantum bits in contact with spin baths. Also, these ensembles are systems which may show many-body localization, at least in the sense of very slow spin dynamics. We present measurements of the autocorrelations of spins on diamond surfaces at infinite temperature in a doubly rotating frame which eliminates local disorder. Strikingly, the timescales in the longitudinal and the transversal channel differ by more than one order of magnitude, which is a factor much greater than one would have expected from simulations of spins on lattices. A previously developed dynamic mean-field theory for spins (spinDMFT) fails to explain this phenomenon. Thus, we improve it by extending it to clusters (CspinDMFT). This theory does capture the striking mismatch up to two orders of magnitude for random ensembles. Without positional disorder, however, the mismatch is only moderate with a factor below 4. The pivotal role of positional disorder suggests that the strong mismatch is linked to precursors of many-body localization.
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- 2023
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47. Mammalian petrosal from the Lower Cretaceous high paleo-latitude Teete locality (Yakutia, Eastern Russia)
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Julia A. Schultz, Rico Schellhorn, Pavel P. Skutschas, Dmitry D. Vitenko, Veniamin V. Kolchanov, Dmitry V. Grigoriev, Ivan T. Kuzmin, Petr N. Kolosov, Alexey V. Lopatin, Alexander O. Averianov, and Thomas Martin
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Zoology ,QL1-991 - Abstract
Abstract A mammalian petrosal from the Lower Cretaceous Teete locality in Yakutia (Russia) shows a prominent and complex system of venous channels in the bony wall of the pars cochlearis surrounding the straight cochlear canal. This complex venous system is distinctive and more strongly developed than in other mammalian petrosals. A bony ridge is present on the ventral side of the cochlear canal endocast, continuing from between fenestra vestibuli and fenestra cochleae in anterior direction. This ridge corresponds to the position of the scala tympani, and is similar to the secondary bony lamina of crown therians, but lacks the sharp laminar edge. The fenestra cochleae is separate from the canal for the aquaeductus cochleae (derived), but the fenestra retains a deep sulcus that resembles the perilymphatic sulcus (plesiomorphic). The fenestra cochleae is oval shaped and deep. The straight cochlear canal with a ridge on the ventral side strongly resembles that of eutriconodontans like Priacodon fruitaensis from the Upper Jurassic of North America. However, thick and extensive venous channels in the pars cochlearis are otherwise known from docodontans. In the Teete petrosal the channels are even more developed, and resemble the pattern recently reported from possible haramiyidan petrosals from the Middle Jurassic of western Siberia (Russia). Both eutriconodontan and haramiyidan dental remains are known from the Teete locality beside that of tritylodontids and docodontans.
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- 2022
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48. Development of two species of the Trypanosoma theileri complex in tabanids
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Alexei Yu. Kostygov, Alexander O. Frolov, Marina N. Malysheva, Anna I. Ganyukova, Daria Drachko, Vyacheslav Yurchenko, and Vera V. Agasoi
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Trypanosomes ,Life cycle ,Vector ,Horseflies ,Deerflies ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background Trypanosoma theileri species complex includes parasites of Bovidae (cattle, sheep, goat, etc.) and Cervidae (deer) transmitted mainly by Tabanidae (horse flies and deerflies) and keds (Hippoboscidae). While morphological discrimination of species is challenging, two big clades, TthI and TthII, each containing parasites isolated from bovids and cervids, have been identified phylogenetically. To date, the development in the vector has been studied in detail only for the ked-transmitted sheep parasite T. melophagium (TthII), while the fate of trypanosomes in tabanids was described only briefly by light microscopy. Methods We collected infected tabanids of various species and identified trypanosomes by molecular phylogenetic analysis. The morphology and development of trypanosomes was studied using the combination of statistical analyses as well as light and electron microscopy. Results Two trypanosome species belonging to both TthI and TthII clades of the T. theileri complex were identified. The phylogenetic position of these two trypanosomes suggests that they parasitize deer. Both species were indiscernible by morphology in the vector and showed the same development in its intestine. In contrast to the previously described development of T. melophagium, both trypanosomes of tabanids only transiently infected midgut and settled mainly in the ileum, while pylorus and rectum were neglected. Meanwhile, the flagellates developing in the tabanid ileum (pyriform epimastigotes and metacyclic trypomastigotes) showed similarities to the corresponding stages in T. melophagium by morphology, mode of attachment to the host cuticle and formation of the fibrillar matrix surrounding the mass of developing parasites. In addition, for the first time to our knowledge we documented extraintestinal stages in these trypanosomes, located in the space between the epithelium and circular muscles. Conclusions The development of different species of flagellates of the T. theileri complex in their insect vectors shows many similarities, which can be explained not only by their common origin, but also the same transmission mode, i.e. contamination of the oral mucosa with the gut content released after squashing the insect either by tongue or teeth. The observed differences (concerning primarily the distribution of developmental stages in the intestine) are associated rather with the identity of vectors than the phylogenetic position of parasites. Graphical Abstract
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- 2022
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49. MATURATION OF STUDENTS’ MENTAL STATES REGULATION SYSTEM DURING THEIR UNIVERSITY STUDIES
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Alexander O. Prokhorov and Albert V. Chernov
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mental state ,mental regulation ,self-regulation technique ,reflection ,education activity ,Psychology ,BF1-990 - Abstract
Background. The study relevance is determined by the need to identify the contribu-tion of consciousness structures to the regulation of mental states and development of the regulatory abilities of the personality. The author’s model of the structural and functional organization of the mental states regulation system served as a theoretical basis of the work.The study objective was to show the maturation of the students’ mental states regula-tion system in the course of university study (at the lectures, seminars, and exams).Sample.The study attended by psychology students at the Institute of Psychology and Education of Kazan Federal University, 151 people in total: 88 students of the 1st year and 63 students of the 4th year of study.Methods. We used various methods for diagnostics of mental characteristics and reg-ulatory abilities, as well as the author’s questionnaires for studying mental states and oper-ational means of self-regulation. Correlation analysis was used to process the data, followed by the calculation of the structure organization index.Results.The study demonstrated that in the period from the P rst to the fourth year of the university studies the students develop new methods and techniques of mental states self-regulation, and the increase in their number is associated with the diversity of the forms of educational activities. In the fourth year of study, the students’ preferable methods of mental states self-regulation are high searching activity, increasing one’s own motivation, developing positive attitudes to study and activating positive volitional states. By the P nal year of study, semantic structures of consciousness, actual reflection and motivation for learning (cognition and self-development) get on the leading roles in self-regulation of mental states. In addition, the importance of the “Self-system”, of the students’ experience and their regulatory abilities is increasing. The study revealed a signiP cant role of self-aware-ness, perseverance, observance and leadership qualities of students in self-regulation of their mental states. Conclusion.The results of the study will contribute to the development of the meth-odology of self-regulated learning and will be useful in designing technologies for the reg-ulation of the subject’s mental states.
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- 2022
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50. Actinides and fission products in reactor graphite after loss-of-flow accident
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Alexander O. Pavlyuk, Sergei G. Kotlyarevskii, Roman I. Kan, Anna G. Volkova, Vasiliy O. Yapaskurt, Elena V. Zakharova, and Andrei A. Shiryaev
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Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Abstract Samples of irradiated graphite from a uranium-graphite reactor contaminated with fuel debris from loss-of-flow accidents, are investigated. Peculiarities of spatial distribution, speciation, and kinetics of leaching by aqueous solution of actinides and fission products are studied at scales from the whole reactor stack down to sub-mm graphite fragments. The main fraction of fuel debris is associated with aluminosilicate-based phases decorating cracks and other defects of damaged graphite details. Elemental composition of actinides and fission products depends on both irradiation and leaching conditions. Significant differences are observed between leach kinetics of various radionuclides; integral leached fraction varies between ~5% for 244Сm to ~90% for 134,137Cs. For some radionuclides sudden massive release due to uneven dissolution of the carrier phases is observed. Disposal of irradiated graphite with significant fraction of fuel debris requires dedicated treatment aimed either at decontamination or at conversion of the radionuclides to insoluble well-fixed form.
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- 2022
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