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Acute diverticulitis (AD) is associated with relevant morbidity/mortality and is increasing worldwide, thus becoming a major issue for national health systems. AD may be challenging, as clinical relevance varies widely, ranging from asymptomatic picture to life-threatening conditions, with continuously evolving diagnostic tools, classifications, and management. A 33-item-questionnaire was administered to residents and surgeons to analyze the actual clinical practice and to verify the real spread of recent recommendations, also by stratifying surgeons by experience. CT-scan remains the mainstay of AD assessment, including cases presenting with recurrent mild episodes or women of child-bearing age. Outpatient management of mild AD is slowly gaining acceptance. A conservative management is preferred in non-severe cases with extradigestive air or small/non-radiologically drainable abscesses. In severe cases, a laparoscopic approach is preferred, with a non-negligible number of surgeons confident in performing emergency complex procedures. Surgeons are seemingly aware of several options during emergency surgery for AD, since the rate of Hartmann procedures does not exceed 50% in most environments and damage control surgery is spreading in life-threatening cases. Quality of life and history of complicated AD are the main indications for delayed colectomy, which is mostly performed avoiding the proximal vessel ligation, mobilizing the splenic flexure and performing a colorectal anastomosis. ICG is spreading to check anastomotic stumps' vascularization. Differences between the two experience groups were found about the type of investigation to exclude colon cancer (considering the experience only in terms of number of colectomies performed), the size of the peritoneal abscess to be drained, practice of damage control surgery and the attitude towards colovesical fistula. [ABSTRACT FROM AUTHOR]

The S239D/I332E mutation in both chain A and chain B of Fc is widely employed to enhance the binding affinity of Fc to its receptor (FcγRIIIa). Despite its popularity in Fc mutation, the kinetic effect of this mutation has not been explored theoretically. This study delves into the impact of S239D and I332E mutations on the association rate between Fc and its receptor by employing computational modeling and transition complex theory. It was revealed that the double mutant exerts the most significant effect, followed by the S239D single mutant and then the I332E single mutant, as evidenced by their association rate constants. We also assessed the mutation effect on the dissociation rate constant indirectly by utilizing experimentally determined binding affinities and the estimated association rate constants. The mutation influence on dissociation outweighs its impact on association, although with varying degrees among the mutants. In particular, the double mutant demonstrated the highest impact on dissociation, while the effects were relatively weak for the two single mutants. These mutation effects on the kinetics of the Fc–Fc receptor interaction correlate with specific molecular interactions at the binding interfaces of the mutant complexes, providing valuable insights for the design of Fc–Fc receptor binding and contributing to our understanding of these crucial interactions in immunology. [ABSTRACT FROM AUTHOR]

A delicate balance between quiescence and division of the radial glia-like stem cells (RGLs) ensures continuation of adult hippocampal neurogenesis (AHN) over the lifespan. Transient or persistent perturbations of this balance due to a brain pathology, drug administration, or therapy can lead to unfavorable long-term outcomes such as premature depletion of the RGLs, decreased AHN, and cognitive deficit. Memantine, a drug used for alleviating the symptoms of Alzheimer's disease, and electroconvulsive seizure (ECS), a procedure used for treating drug-resistant major depression or bipolar disorder, are known strong AHN inducers; they were earlier demonstrated to increase numbers of dividing RGLs. Here, we demonstrated that 1-month stimulation of quiescent RGLs by either memantine or ECS leads to premature exhaustion of their pool and altered AHN at later stages of life and that aging of the brain modulates the ability of the quiescent RGLs to be recruited into the cell cycle by these AHN inducers. Our findings support the aging-related divergence of functional features of quiescent RGLs and have a number of implications for the practical assessment of drugs and treatments with respect to their action on quiescent RGLs at different stages of life in animal preclinical studies. [ABSTRACT FROM AUTHOR]

Multisystem inflammatory syndrome in children (MIS-C) is a rare but severe hyperinflammatory condition that may occur following SARS-CoV-2 infection. This retrospective, descriptive study of children hospitalized with multisystem inflammatory syndrome in children (MIS-C) in 12 tertiary care centers from 3/11/2020 to 12/31/2021. Demographics, clinical and laboratory characteristics, treatment and outcomes are described. Among 145 patients (95 males, median age 8.2 years) included, 123 met the WHO criteria for MIS-C, while 112 (77%) had serological evidence of SARS-CoV-2 infection. Fever was present in 99%, gastrointestinal symptoms in 77%, mucocutaneous involvement in 68% and respiratory symptoms in 28%. Fifty-five patients (38%) developed myocarditis, 29 (20%) pericarditis and 19 (13%) coronary aneurysms. Among the above cases 11/55 (20%), 1/29 (3.4%) and 5/19 (26.3%), respectively, cardiac complications had not fully resolved at discharge. Underlying comorbidities were reported in 18%. Median CRP value was 155 mg/l, ferritin 535 ng/ml, PCT 1.6 ng/ml and WBC 14.2 × 109/mm3. Most patients had elevated troponin (41.3%) and/or NT-pro-BNP (49.6%). Intravenous immunoglobulin plus corticosteroids were used in 117/145 (80.6%), monotherapy with IVIG alone in 13/145 (8.9%) and with corticosteroids alone in 2/145 (1.3%). Anti-IL1 treatment was added in 15 patients (10.3%). Thirty-three patients (23%) were admitted to the PICU, 14% developed shock and 1 required ECMO. Mortality rate was 0.68%. The incidence of MIS-C was estimated at 0.69/1000 SARS-CoV-2 infections. Patients who presented with shock had higher levels of NT-pro-BNP compared to those who did not (p < 0.001). Acute kidney injury and/or myocarditis were associated with higher risk of developing shock. Conclusion: MIS-C is a novel, infrequent but serious disease entity. Cardiac manifestations included myocarditis and pericarditis, which resolved in most patients before discharge. Timely initiation of immunomodulatory therapy was shown to be effective. NT-pro-BNP levels may provide a better prediction and monitoring of the disease course. Further research is required to elucidate the pathogenesis, risk factors and optimal management, and long-term outcomes of this clinical entity. What is Known: • MIS-C is an infrequent but serious disease entity. • Patients with MIS-C present with multi-organ dysfunction, primarily involving the gastrointestinal and cardiovascular systems. What is New: • NT-pro-BNP levels may provide a better prediction and monitoring of the disease course. • Acute kidney injury and/or myocarditis were associated with higher risk of developing shock. [ABSTRACT FROM AUTHOR]

Chronic kidney disease (CKD) affects more than one in ten people worldwide. However, results from the REVEAL-CKD study suggest that it is often not diagnosed. Many patients are therefore unaware that they have CKD, putting them at increased risk of disease progression and complications. Empowering patients with knowledge about CKD will allow them to become active participants in their own care, driving improvements in diagnosis rates and changing patient outcomes for the better. In this article, we provide patient and clinician perspectives on the importance of early CKD diagnosis and management. We present an overview of the tests commonly used to diagnose CKD in clinical practice, as well as actionable suggestions for patients, clinicians, and health policymakers that could help improve disease detection and treatment. 5rJyPLjpBJj3_1LDfE3xyi Navdeep Tangri, a nephrologist and epidemiologist at the University of Manitoba, and Jane DeMeis, a patient living with chronic kidney disease, discuss how results from the REVEAL-CKD study highlight the need for change to improve management of chronic kidney disease. Video Abstract (MP4 141866 KB) [ABSTRACT FROM AUTHOR]

Background: Macrophages (Mφ) can exist along a spectrum of phenotypes that include pro-inflammatory (M1) or anti-inflammatory (M2) immune cells. Mφ colony stimulating factor (M-CSF) and granulocyte Mφ colony stimulating factor (GM-CSF) are cytokines important in hematopoiesis, polarization and activation of Mφ. Methods and results: To gain a greater understanding of the relationship between GM-CSF and M-CSF, we investigated an in vitro model of differentiation to determine if GM-CSF and M-CSF can antagonize each other, in terms of Mφ phenotype and functions. We determined that Mφ cultured in mixed M-CSF: GM-CSF ratios exhibit M1-like GM-CSF-treated macrophage phenotype when the ratios of the two cytokines are 1:1 in culture. Moreover, GM-CSF is dominant over M-CSF in influencing Mφ production of proinflammatory cytokines such as IL-6, TNFα, and IL-12p40, and the anti-inflammatory cytokine IL-10. Conclusions: Our data established that GM-CSF is more dominant over M-CSF, triggering the Mφ to become pro-inflammatory cells. These findings provide insight into how GM-CSF can influence Mφ activation with implications in inflammatory diseases where the Mφ status can play a significant role in supporting the inflammatory conditions. [ABSTRACT FROM AUTHOR]

Semiarid regions are often affected by water scarcity and poor water quality. Seasonal changes in precipitation and drought events increase the pressure of use on water bodies and their pollution. In Central Northern Namibia, a high seasonal intra- and inter-annual variability of precipitation caused a 5-year lasting drought period. In the semiarid region, ephemeral channels and water pans represent the main water source, besides the institutionalized water supply. No systematic analysis of its quality has been conducted so far. The states of the surface waters at the end of the dry season in 2017 and the end of the rainy seasons in 2018 and 2019 were characterized by the analysis of physical–chemical parameters, focusing on usability. The first results show coarse contamination of the waters, which results in high turbidity values. Salt concentrations, such as Ca2+ and Na+, greatly increased due to evaporation. Al is present in high concentrations in solid and liquid phases, which indicates direct anthropogenic pollution. Spatial differences are evident in the study area and based on the precipitation gradient, land use, and population density. The waters cannot be used as drinking water without prior treatment. [ABSTRACT FROM AUTHOR]

Current literature regarding the association of vitamin D insufficiency and food allergy is contradicting. The purpose of our study was to investigate this association. This is a systematic review and meta-analysis according to the PRISMA statement. PubMeD and Scopus databases were systematically searched for case–control studies investigating the association between pediatric food allergy and vitamin D insufficiency. Our search yielded 806 studies. Ten final studies were considered eligible for qualitative and quantitative analysis. Children with vitamin D insufficiency were found to have 68% more probability to present a food allergy episode (adjusted pooled OR: 1.68, 95% CI [1.25–2.27], p-value: 0.001). In their second year of life they were 4 times more likely to present a food allergy episode (adjusted pooled OR: 4.06, 95% CI [1.93–8.56], p-value: < 0.001), and 56% more probable to develop food sensitization (OR: 1.56, 95% CI [1.15–2.11], p-value: < 0.004). Children in Australia with vitamin D insufficiency were almost 4 times more likely to develop egg sensitization (adjusted OR: 3.79, 95% CI [1.19–12.08], p-value: 0.024). Children with vitamin D insufficiency were almost twice as likely to have peanut sensitization (OR: 1.96, 95% CI [1.08–3.57], p-value: 0.028). Conclusion: Decreased maternal vitamin D levels and infant vitamin D insufficiency appear to increase the incidence of food allergies, particularly in the second year of life. To confirm this association, multicenter longitudinal studies are required. What is Known: • In newborns and young children, vitamin D deficiency and insufficiency are prevalent. • The exact role of vitamin D in atopic diseases remains controversial. What is New: • Decreased maternal vitamin D levels and infant vitamin D insufficiency appear to increase the incidence of food allergies. This association is more evident in the second year of life. [ABSTRACT FROM AUTHOR]

Background: Megalocytiviruses (MCV) are double-stranded DNA viruses that infect fish. Two species within the genus are epidemiologically important for fish farming: red sea bream iridovirus (RSIV) and infectious spleen and kidney necrosis virus (ISKNV). The objective of this work was to study regions that allow the differentiation and correct diagnosis of RSIV and ISKNV. Methods: The regions ORF450L, ORF342L, ORF077, and the intergenic region between ORF37 and ORF42R were sequenced and compared with samples from the database. Results: The tree constructed using the sequencing of the PCR product Megalocytivirus. ORF077 separated the three major clades of MCV. RISV genotypes were well divided, but not ISKNV. All qPCRs tests showed acceptable repeatability values, that is, less than 5%. Conclusion: Two qPCRs for ISKNV detection and two for RSIV were considered suitable for use in the diagnosis and typing of MCV. The results of this study demonstrate the importance of an accurate evaluation of methodologies for the differentiation of MCV. [ABSTRACT FROM AUTHOR]

Background: Hereditary fructose intolerance (HFI) is a rare inborn error of fructose metabolism caused by the deficiency of aldolase B. Since treatment consists of a fructose-, sucrose- and sorbitol-restrictive diet for life, patients are at risk of presenting vitamin deficiencies. Although there is no published data on the status of these vitamins in HFI patients, supplementation with vitamin C and folic acid is common. Therefore, the aim of this study was to assess vitamin C and folate status and supplementation practices in a nationwide cohort of HFI patients.Methods: Vitamin C and folic acid dietary intake, supplementation and circulating levels were assessed in 32 HFI patients and 32 age- and sex-matched healthy controls.Results: Most of the HFI participants presented vitamin C (96.7%) and folate (90%) dietary intake below the recommended population reference intake. Up to 69% received vitamin C and 50% folic acid supplementation. Among HFI patients, 15.6% presented vitamin C and 3.1% folate deficiency. The amount of vitamin C supplementation and plasma levels correlated positively (R = 0.443; p = 0.011). Interestingly, a higher percentage of non-supplemented HFI patients were vitamin C deficient when compared to supplemented HFI patients (30% vs. 9.1%; p = 0.01) and to healthy controls (30% vs. 3.1%; p < 0.001).Conclusions: Our results provide evidence for the first time supporting vitamin C supplementation in HFI. There is great heterogeneity in vitamin supplementation practices and, despite follow-up at specialised centres, vitamin C deficiency is common. Further research is warranted to establish optimal doses of vitamin C and the need for folic acid supplementation in HFI. [ABSTRACT FROM AUTHOR]

Introduction: Lichen planopilaris (LPP) is characterized by chronic scarring alopecia that is progressive and typically refractory to therapy. Current drug treatments are suboptimal and not applicable for long-term use because of the high potential for adverse effects, warranting safer and more effective treatment alternatives. Methods: Based on our previous success in treating a patient with central centrifugal cicatricial alopecia using a topical botanical formulation (Gashee), we reviewed records of four patients with biopsy-proven LPP treated with the topical formulation alone or in combination with its oral preparation. Three patients had failed previous treatment with intralesional steroid injections, topical minoxidil, tacrolimus, and clobetasol. Physical examination and photographic documentation were also used as outcome measures. Treatment duration with the botanical formulations ranged from 6 weeks to 9.5 months. Results: All patients showed overall improvement in surrogate indicators of LPP activity as evidenced by the disappearance of symptoms (pruritus, tenderness, scalp irritation, and hair shedding), improvement in hair growth, and reduction in redness. All reported a high satisfaction level and no adverse effects. Conclusions: Patients with treatment-refractory LPP responded to a novel botanical treatment. To the best of our knowledge, this is the first published report of LPP responding to a plant-based natural treatment. Further evaluation of this treatment in a controlled trial with a larger number of patients is warranted. Plain Language Summary: Lichen planopilaris is a chronic and progressive condition, most commonly affecting middle-aged women. It results in scalp inflammation, scarring, and ultimately permanent hair loss. Treatments are typically ineffective in the long term and are associated with side effects that limit their use. We report success in treating four patients using a new botanical formulation called Dr. UGro Gashee as the sole therapy for a duration ranging from 6 weeks to 9.5 months. The treatment was administered topically or in combination with its oral formulation. All the patients showed cessation of disease progression with significant hair regrowth. They also reported complete resolution of scalp itch, tenderness, and irritation, with no adverse effects. Our report is the first published study of lichen planopilaris responding to a plant-based natural treatment and warrants further evaluation in larger controlled trials. [ABSTRACT FROM AUTHOR]

Engineering of Fc for improved affinity to its receptor, FcγRIIIa, can enhance the therapeutic activity of monoclonal antibodies. S239D/I332E mutation of Fc has been extensively employed in various Fc engineering studies. Still, it is not clear how the mutations have structurally influenced the molecular interactions between Fc and FcγRIIIa. In this study, the point or combined mutations of S239D/I332E were introduced into one chain (A) or the other chain (chain B) of the homodimeric Fc domain computationally. Their structural effects on the binding to FcγRIIIa were investigated through a computational docking method. These results showed that the chain-specific point mutation, S239D induced a new salt-bridge with the receptor in A and B chains of Fc, whereas I332E mutation generated a new salt-bridge with the receptor only in A chain. The combined mutation study identified that the Fc variant with four mutations reproduced the three salt-bridges. This showed that the mutation of S239D and I332E in chain A of Fc induced complex salt-bridge formation with the Lys158 of FcγRIIIa. This study is expected to provide more structural insight into Fc variants' design based on S239D/I332E mutation. [ABSTRACT FROM AUTHOR]

Nicolelis wrote in his 2003 review on brain-machine interfaces (BMIs) that the design of a successful BMI relies on general physiological principles describing how neuronal signals are encoded. Our study explored whether neural information exchanged between brains of different species is possible, similar to the information exchange between computers. We show for the first time that single words processed by the guinea pig auditory system are intelligible to humans who receive the processed information via a cochlear implant. We recorded the neural response patterns to single-spoken words with multi-channel electrodes from the guinea inferior colliculus. The recordings served as a blueprint for trains of biphasic, charge-balanced electrical pulses, which a cochlear implant delivered to the cochlear implant user's ear. Study participants completed a four-word forced-choice test and identified the correct word in 34.8% of trials. The participants' recognition, defined by the ability to choose the same word twice, whether right or wrong, was 53.6%. For all sessions, the participants received no training and no feedback. The results show that lexical information can be transmitted from an animal to a human auditory system. In the discussion, we will contemplate how learning from the animals might help developing novel coding strategies. [ABSTRACT FROM AUTHOR]

Structural information of Fc-Fc receptor interaction may contribute to the design of drugs or therapeutic antibodies associated with the interaction. Computational protein-protein docking can be employed in structural study of protein-protein interaction, but its efficiency and reliability are still unstable and need to be validated and optimized for respective target protein complexes. In this study, we investigated and assessed the computational modeling efficiency of Fc-FcγR complex through HADDOCK by defining five different sets of active residues, a major parameter to determine the prediction efficiency of HADDOCK. The binding residues identified experimentally or the residues in the binding pocket were confirmed to be efficient active residues to achieve a high prediction efficiency, and too narrower or wider specification of active residues led to poor prediction efficiency. Most binding residues and crucial molecular interactions such as conserved interactions and hydrogen bonds in the crystal structure were reproduced in the best model. The HADDOCK docking condition determined in this study is expected to be applied to the computational characterization of various Fc-Fc receptor complexes and mutants. [ABSTRACT FROM AUTHOR]

Levulinic acid (LA) is currently one of the most promising chemicals derived from biomass. However, its large-scale production is hampered by the challenges in biomass hydrolysis and the poor selectivity due to the formation of humins (HUs). This study addresses these challenges using the biorefinery concept of biomass fractionation. A three-step process (pretreatment, delignification, and acid-catalyzed conversion) was optimized to produce LA from SCB considering the yield (YLA), efficiency (ELA), and concentration of LA (CLA) as functions of temperature, reaction time, acid concentration, and solids loading. By means of a multi-response optimization, values of YLA (20.9 ± 1.25 g/100gISF-D), ELA (37.5 ± 2.24 mol%), and CLA (25.1 ± 1.50 g/L) were obtained at 180 °C, 75 min, 7.0% w/v H2SO4, and 12.0% w/v of solids loading. Six scenarios for production of LA were analyzed in terms of yields of LA, HUs, lignin, and other sugar-derived products considering one-, two-, or three-step processes. The economic analysis indicated that the three-step scenario delivers better economic figures given that other valuable biomass fractions (hemicellulosic sugars and lignin) are better used and contribute to the overall economic performance of the process. The results also demonstrate the burden of HUs in the economics of the process because it was shown that the largest production of LA is also linked to the largest formation of HUs, which does not necessarily yield the best economic results. These findings indicate the importance of added value by-products for the profitable production of LA in biorefineries. [ABSTRACT FROM AUTHOR]

The results of genetic and epidemiological study of monogenic hereditary diseases (HD) among children of the Karachay-Cherkess Republics are presented. The surveyed population comprised 410 368 individuals (Cherkessk and ten rural areas), including 90 739 children (22.11%). The examination was performed following the original protocol for genetic-epidemiological studies (developed by the Research Centre for Medical Genetics) making it possible to register not less than 3500 HD and syndromes. One hundred eighty-three nosological forms of HD (922 patients from 764 families) were registered in the child population, including 100 patients with AD (459 patients from 366 families), 60 patients with AR (372 patients from 326 families), and 23 patients with X-linked inheritance (91 patients from 72 families). The structure of diversity is determined, and frequent HDs are described in accordance with the main classification by organ and systemic types of disease: neurological, ophthalmic, genodermatoses, skeletal, hereditary syndromes, and other pathology. There were 55 frequent HDs (30.05%)—the number of patients in this group was 739 (80.15% of sick children). The load of AD, AR, and X-linked pathology for urban and rural child population was calculated. Differences in HD load were identified. On the basis of correlations between the load and FST, the causes of the observed differentiation of subpopulations were proposed. [ABSTRACT FROM AUTHOR]

The diversity and prevalence of hereditary diseases (HDs) among Nogais of the Karachay-Cherkess Republic (KChR) are described. The size of the surveyed KChR population was 387231 individuals, including 3.81% Nogais (14741 individuals). We revealed 36 nosological forms of HDs (110 patients from 81 families): 22 with autosomal dominant (AD) inheritance, 10 with autosomal recessive (AR) inheritance, and 4 with X-linked inheritance. The prevalence of HDs in Nogais was 1: 134. The features of HD diversity in Nogais were determined in comparison with the previously surveyed populations of Russia. The accumulation of Ehlers-Danlos syndrome (1: 388), AD amelogenesis imperfecta (1: 3685), AD ichthyosis (1: 4914), AR nonsyndromic mental retardation (1: 1340), AR Gilbert syndrome (1: 4914), and X-linked inherited deficit of glucose-6-dehydrogenase (1: 1774 males) was established. The analysis of heterozygous carriage of mutations “major” for Russia in the genes of the four following AR diseases in 118 unrelated clinically healthy Nogais (236 analyzed chromosomes) was performed: cystic fibrosis (13 mutations in the CFTR gene: CFTRdele2,3 (21 kb), F508del, I507del, 1677delTA, 2184insA, 2143delT, 2183AA>G, 2184delA, 394delTT, 3821delT, L138ins, E92K, W1282X); phenylketonuria (six frequent mutations in the PAH gene: R261X, R408W, R413P, F331S, P211T, P211L); nonsyndromic sensorineural hearing loss (35delG mutation in the GJB2 gene); and Gilbert syndrome (an increase in the number of TA repeats in the UGT1A1 gene). Allelic specificity for all studied genes in the Nogai people was revealed. [ABSTRACT FROM AUTHOR]

A 3D-model was developed to study the effects of hypolimnetic aeration on the temperature profile of a thermally stratified Lake Vesijärvi (southern Finland). Aeration was conducted by pumping epilimnetic water through the thermocline to the hypolimnion without breaking the thermal stratification. The model used time transient equation based on Navier-Stokes equation. The model was fitted to the vertical temperature distribution and environmental parameters (wind, air temperature, and solar radiation) before the onset of aeration, and the model was used to predict the vertical temperature distribution 3 and 15 days after the onset of aeration (1 August and 22 August). The difference between the modelled and observed temperature was on average 0.6 °C. The average percentage model error was 4.0% on 1 August and 3.7% on 22 August. In the epilimnion, model accuracy depended on the difference between the observed temperature and boundary conditions. In the hypolimnion, the model residual decreased with increasing depth. On 1 August, the model predicted a homogenous temperature profile in the hypolimnion, while the observed temperature decreased moderately from the thermocline to the bottom. This was because the effect of sediment was not included in the model. On 22 August, the modelled and observed temperatures near the bottom were identical demonstrating that the heat transfer by the aerator masked the effect of sediment and that exclusion of sediment heat from the model does not cause considerable error unless very short-term effects of aeration are studied. In all, the model successfully described the effects of the aerator on the lake's temperature profile. The results confirmed the validity of the applied computational fluid dynamic in artificial aeration; based on the simulated results, the effect of aeration can be predicted. [ABSTRACT FROM AUTHOR]

This paper reports an experimental degradation study of nineteen multi-class pharmaceutical products present in the influent wastewater arriving at the Daugavgriva wastewater treatment plant. Collected wastewater samples were filtered and irradiated by electron beam and gamma radiation both generated from a 5 MeV linear particle accelerator. The samples were exposed to ten absorbed doses (0.5-25 kGy) produced at high dose rates (600 and 1200 kGy h for accelerated electrons, as well as 22.5 and 37.5 kGy h for gamma radiation). The analysis by a sensitive liquid chromatography-mass spectrometry method indicated that the initial concentrations of pharmaceutical residues were effectively reduced by up to 90-100% in eighty per cent of the cases when samples were exposed to 0.5-5 kGy of electron beam or gamma radiation treatment. Higher doses (>5 kGy) were needed to decompose macrolide antibiotics. The use of electron beam radiation showed some advantages due to the reduced exposure time, thus enabling a more energy efficient treatment resulting in the degradation of pharmaceutical residues comparable to that achieved by gamma irradiation. Microbiological studies indicated the pronounced degradation effect on bacterial contamination of wastewater, which was successfully eliminated upon increasing the radiation, dose up to 7-12 kGy. [ABSTRACT FROM AUTHOR]

The antioxidant potential of various marine natural products is well documented. The aim of this study was to evaluate the antioxidant potential of a rare halogenated monoterpene, namely; 1 E,3 R,4 S,5 E,7 Z-1-bromo-3,4,8-trichloro-7-(dichloromethyl)-3-methylocta-1,5,7-triene ( 1) for the first time. This compound was isolated from a Namibian red algal Plocamium species. The antioxidant activity of the compound was evaluated using a series of antioxidant assays, namely; 2,2-diphenyl-1-picryl-hydrazyl radical (DPPH), reducing power, nitric oxide (NO) and hydrogen peroxide (HO). The compound demonstrated remarkable DPPH, NO and HO scavenging activities with IC values of 0.05 ± 0.01, 4.18 ± 0.22 and 5.58 ± 1.11 mM, respectively. The reducing power of the compound increased with an increase in concentration. These results were compared to the absorbance of ascorbic acid, which was used as a standard control in all the antioxidant assays. The results strongly suggest that compound 1 is a promising antioxidant agent with potential commercial applications. [ABSTRACT FROM AUTHOR]

Long-term plasticity is well documented in synapses between glutamatergic principal cells in the cortex both in vitro and in vivo. Long-term potentiation (LTP) and -depression (LTD) have also been reported in glutamatergic connections to hippocampal GABAergic interneurons expressing parvalbumin (PV+) or nitric oxide synthase (NOS+) in brain slices, but plasticity in these cells has not been tested in vivo. We investigated synaptically-evoked suprathreshold excitation of identified hippocampal neurons in the CA1 area of urethane-anaesthetized rats. Neurons were recorded extracellularly with glass microelectrodes, and labelled with neurobiotin for anatomical analyses. Single-shock electrical stimulation of afferents from the contralateral CA1 elicited postsynaptic action potentials with monosynaptic features showing short delay (9.95 ± 0.41 ms) and small jitter in 13 neurons through the commissural pathway. Theta-burst stimulation (TBS) generated LTP of the synaptically-evoked spike probability in pyramidal cells, and in a bistratified cell and two unidentified fast-spiking interneurons. On the contrary, PV+ basket cells and NOS+ ivy cells exhibited either LTD or LTP. An identified axo-axonic cell failed to show long-term change in its response to stimulation. Discharge of the cells did not explain whether LTP or LTD was generated. For the fast-spiking interneurons, as a group, no correlation was found between plasticity and local field potential oscillations (1-3 or 3-6 Hz components) recorded immediately prior to TBS. The results demonstrate activity-induced long-term plasticity in synaptic excitation of hippocampal PV+ and NOS+ interneurons in vivo. Physiological and pathological activity patterns in vivo may generate similar plasticity in these interneurons. [ABSTRACT FROM AUTHOR]

The current study examined the level of friendship satisfaction of children with autism spectrum disorder (ASD) and their nominated friends (with and without diagnosis of ASD). A total of 77 target children with ASD and friends from 49 nominated friendships participated in the study. Relatively high levels of friendship satisfaction were reported by both target children and their nominated friends with no overall difference between dyads involving typically developing friends and friends with ASD. Analysis at the individual dyad level showed a high level of agreement on the reported level of satisfaction across the target participants and their friends. Limitations and directions for future research are presented. [ABSTRACT FROM AUTHOR]

There has been limited research exploring the similarity of perception of friendship quality between children with Autism Spectrum Disorder (ASD) and their friends. In this study, 45 children with ASD participated together with their friends. Two levels of friendship quality congruency were investigated: reciprocity and mutuality. A high proportion of the friendships were reciprocated for both the mixed and non-mixed friendship groups. Nevertheless, students with ASD reported substantial differences in perceptions of their friendship quality as compared to their nominated friends. The findings of the present study mirrored those of previous research with typically developing children. Further study is required to systematically investigate the differences in friendship quality perceptions within friendship dyads for both typically developing children and those with ASD diagnosis. [ABSTRACT FROM AUTHOR]

Magnetic resonance imaging (MRI)-enabled cancer screening has been shown to be a highly sensitive method for the early detection of breast cancer. Computer-aided detection systems have the potential to improve the screening process by standardizing radiologists to a high level of diagnostic accuracy. This retrospective study was approved by the institutional review board of Sunnybrook Health Sciences Centre. This study compares the performance of a proposed method for computer-aided detection (based on the second-order spatial derivative of the relative signal intensity) with the signal enhancement ratio (SER) on MRI-based breast screening examinations. Comparison is performed using receiver operating characteristic (ROC) curve analysis as well as free-response receiver operating characteristic (FROC) curve analysis. A modified computer-aided detection system combining the proposed approach with the SER method is also presented. The proposed method provides improvements in the rates of false positive markings over the SER method in the detection of breast cancer (as assessed by FROC analysis). The modified computer-aided detection system that incorporates both the proposed method and the SER method yields ROC results equal to that produced by SER while simultaneously providing improvements over the SER method in terms of false positives per noncancerous exam. The proposed method for identifying malignancies outperforms the SER method in terms of false positives on a challenging dataset containing many small lesions and may play a useful role in breast cancer screening by MRI as part of a computer-aided detection system. [ABSTRACT FROM AUTHOR]

We consider a transportation problem arising in public bicycle sharing systems: To avoid rental stations to run entirely empty or full, a fleet of vehicles continuously performs tours moving bikes among stations. In the static problem variant considered in this paper, we are given initial and target fill levels for all stations, and the goal is primarily to find vehicle tours including corresponding loading instructions in order to minimize the deviations from the target fill levels. As secondary objectives we are further interested in minimizing the tours' total duration and the overall number of loading actions. For this purpose we first propose a fast greedy construction heuristic and extend it to a PILOT method that evaluates each candidate station considered for addition to the current partial tour in a refined way by looking forward via a recursive call. Next we describe a Variable Neighborhood Descent (VND) that exploits a set of specifically designed neighborhood structures in a deterministic way to locally improve the solutions. While the VND is processing the search space of candidate routes to determine the stops for vehicles at unbalanced rental stations, the number of bikes to be loaded or unloaded at each stop is derived by an efficient method. Four alternatives are considered for this embedded procedure based on a greedy heuristic, two variants of maximum flow calculations, and linear programming. Last but not least, we investigate a general Variable Neighborhood Search (VNS) and variants of a Greedy Randomized Adaptive Search Procedure (GRASP) for further diversification and extended runs. Rigorous experiments using benchmark instances derived from a real-world scenario in Vienna with up to 700 stations document the performance of the suggested approaches and individual pros and cons. While the VNS yields the best results on instances of moderate size, a PILOT/GRASP hybrid turns out to be superior on very large instances. If solutions are required in short time, the construction heuristic or PILOT method optionally followed by VND still yield reasonable results. [ABSTRACT FROM AUTHOR]

The abundance and predominant groups of bacteria, filamentous fungi and yeasts have been studied by culture-dependent microbiological methods in peat probes obtained in two Latvian balneotherapy spa sites, Kemeri and Baldone. Unsterilized peat samples from both the sites contained 5.7-8.1 log bacterial colony-forming units (CFU) and 3.0-5.3 log fungal CFU per gram of dry peat. Isolated species belonged to Alpha-, Beta-, and Gamma- Proteobacteria, Actinobacteria, Clostridia, Bacilli and Flavobacteria as well as to filamentous fungi and yeasts. The composition of microbial population of the peat from both sites shared just four micro-organism groups ( Bacillus mycoides, Burkholderia cepacia, Streptomyces spp. and Trichoderma spp.) within totally 36 groups identified. No pathogenic bacteria or fungi and no faecal pollution indicators were recovered. Decimal reduction doses for micro-organisms in peat samples and radiation sterilization doses of peat for the gamma and electron beam radiation were determined. The highest radiation resistance was observed for B. mycoides and Aureobasidium sp. Gamma-sitosterol was the most abundant hydrophobic organic compound in both peats according to GC-MS data. All the sterilization procedures increased concentration of alkanes, alcohols, and ketones and decreased the amount of fatty acids. Heat sterilization proved to be more preserving for the peat sterols than the radiation sterilization. It is concluded that the heat and radiation sterilization methods induce different changes of the profile of hydrophobic organic compounds of balneological peats, what may lead to different therapeutic effects at their application. [ABSTRACT FROM AUTHOR]

We consider the stochastic dynamics that is the Boltzmann-Grad limit of the Hamiltonian dynamics of a system of hard spheres. A new concept of averages over states of stochastic systems is introduced, in which the contribution of the hypersurfaces on which stochastic point particles interact is taken into account. We give a rigorous derivation of the infinitesimal operators of semigroups of evolution operators. [ABSTRACT FROM AUTHOR]

Stochastic dynamics corresponding to the Boltzmann hierarchy is constructed. The Liouville-Itô equations are obtained, from which we derive the Boltzmann hierarchy regarded as an abstract evolution equation. We construct the semigroup of evolution operators and prove the existence of solutions of the Boltzmann hierarchy in the space of sequences of integrable and bounded functions. On the basis of these results, we prove the existence of global solutions of the Boltzmann equation and the existence of the Boltzmann-Grad limit for an arbitrary time interval. [ABSTRACT FROM AUTHOR]

We study equilibrium states of systems of hard spheres in the Boltzmann-Enskog limit ( d→0, 1/ v→∞ ( z→∞), and d 3 (1/ v)=const ( d 3 z=const)). For this purpose, we use the Kirkwood-Salsburg equations. We prove that, in the Boltzmann-Enskog limit, solutions of these equations exist and the limit distribution functions are constant. By using the cluster and compatibility conditions, we prove that all distribution functions are equal to the product of one-particle distribution functions, which can be represented as power series in z= d 3 z with certain coefficients. [ABSTRACT FROM AUTHOR]

Cancer screening with magnetic resonance imaging (MRI) is currently recommended for very high risk women. The high variability in the diagnostic accuracy of radiologists analyzing screening MRI examinations of the breast is due, at least in part, to the large amounts of data acquired. This has motivated substantial research towards the development of computer-aided diagnosis (CAD) systems for breast MRI which can assist in the diagnostic process by acting as a second reader of the examinations. This retrospective study was performed on 184 benign and 49 malignant lesions detected in a prospective MRI screening study of high risk women at Sunnybrook Health Sciences Centre. A method for performing semi-automatic lesion segmentation based on a supervised learning formulation was compared with the enhancement threshold based segmentation method in the context of a computer-aided diagnostic system. The results demonstrate that the proposed method can assist in providing increased separation between malignant and radiologically suspicious benign lesions. Separation between malignant and benign lesions based on margin measures improved from a receiver operating characteristic (ROC) curve area of 0.63 to 0.73 when the proposed segmentation method was compared with the enhancement threshold, representing a statistically significant improvement. Separation between malignant and benign lesions based on dynamic measures improved from a ROC curve area of 0.75 to 0.79 when the proposed segmentation method was compared to the enhancement threshold, also representing a statistically significant improvement. The proposed method has potential as a component of a computer-aided diagnostic system. [ABSTRACT FROM AUTHOR]

Nanocomposite materials on the basis of ultra-high-molecular-weight polyethylene and multilayer carbon nanotubes (MCNTs), the concentration of which varied from 0.1 to 1 wt %, were prepared by combined deposition from solution. The presence of carbon nanotubes in the polymer matrix leads to structural changes strongly affecting the physical properties of composites. The interrelation between the macroscopic behavior under deformation and the microstructure of the composite was studied in situ by X-ray structural analysis with the application of synchrotron radiation. The results indicate that the martensite transformation of the orthorhombic phase of ultra-high-molecular-weight polyethylene into the monoclinic one induced by the deformation and the relative content of the metastable phase are determined by the presence of carbon nanotubes. [ABSTRACT FROM AUTHOR]

This study investigates the use of a proposed vector machine formulation with application to dynamic contrast-enhanced magnetic resonance imaging examinations in the context of the computer-aided diagnosis of breast cancer. This paper describes a method for generating feature measurements that characterize a lesion's vascular heterogeneity as well as a supervised learning formulation that represents an improvement over the conventional support vector machine in this application. Spatially varying signal-intensity measures were extracted from the examinations using principal components analysis and the machine learning technique known as the support vector machine (SVM) was used to classify the results. An alternative vector machine formulation was found to improve on the results produced by the established SVM in randomized bootstrap validation trials, yielding a receiver-operating characteristic curve area of 0.82 which represents a statistically significant improvement over the SVM technique in this application. [ABSTRACT FROM AUTHOR]

During cell division, spindle microtubules attach to chromosomes through kinetochores, protein complexes on the chromosome. The central question is how microtubules find kinetochores. According to the pioneering idea termed search-and-capture, numerous microtubules grow from a centrosome in all directions and by chance capture kinetochores. The efficiency of search-and-capture can be improved by a bias in microtubule growth towards the kinetochores, by nucleation of microtubules at the kinetochores and at spindle microtubules, by kinetochore movement, or by a combination of these processes. Here we show in fission yeast that kinetochores are captured by microtubules pivoting around the spindle pole, instead of growing towards the kinetochores. This pivoting motion of microtubules is random and independent of ATP-driven motor activity. By introducing a theoretical model, we show that the measured random movement of microtubules and kinetochores is sufficient to explain the process of kinetochore capture. Our theory predicts that the speed of capture depends mainly on how fast microtubules pivot, which was confirmed experimentally by speeding up and slowing down microtubule pivoting. Thus, pivoting motion allows microtubules to explore space laterally, as they search for targets such as kinetochores. [ABSTRACT FROM AUTHOR]

In this article theoretical developments in the field of nanorobots and methods of nanorobot construction at the microscopic and molecular levels are analyzed. The issues of simulation of nanorobots and their components and the questions of control and energy sources are considered. Some experimental results and examples of applications are presented. [ABSTRACT FROM AUTHOR]

Microactuators are an important tool for precise manipulation of components and materials in nanotechnologies. The problems of design and application of microactuators for micro- and nanopositioning, microassembly, and microrobotics are considered in this paper. The basic parameters and models of piezoelectric, magnetostriction, electromagnetic, electrostatic, electrothermal, and hybrid microactuators are described. A general information approach that implies the description of physical models used in order to analyze microactuator behavior and optimize their design is considered. [ABSTRACT FROM AUTHOR]