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Background/Objectives: This study evaluates the applicability of a comprehensive two-dimensional gas chromatography−flame ionisation detection (GC×GC−FID) approach for the simultaneous determination of 12 underivatised psychoactive drugs, including new psychoactive substances, that comprised of amphetamine, methamphetamine, mephedrone, 3,4-methylenedioxyamphetamine, 3,4-methylenedioxymethamphetamine, α-pyrrolidinovalerophenone, n-ethylpentylone (ephylone), norketamine, ketamine, 3,4-methylenedioxypyrovalerone, methadone, and cocaine. Methods: Separation was effected using a non-polar first dimension (1D) and a polar second dimension (2D) column, demonstrating an improved separation of drug compounds compared to a polar/non-polar column configuration. Interference-free baseline separation of all psychoactive compounds in a urine matrix was achieved within 8 min. The GC×GC−FID method was validated according to the guidelines defined by Standard Practices for Method Validation in Forensic Toxicology. Results: The calibration curves for the 12 psychoactive drugs were well correlated (r2 > 0.99) within the concentration ranges of 50–1500 ng mL−1. Detection limits of 10–20 ng mL−1 were obtained, and good repeatability and reproducibility (CV < 11.4%) were attained for retention times and peak areas. Method recoveries for the small-scale solvent extraction procedure ranged from 96.9 to 114.5%, and bias was between −3.1% and 14.5%. Conclusions: The validated approach was successfully applied for the determination of these illicit compounds in spiked urine samples of different concentrations, highlighting its potential for rapid forensic drug screening. [ABSTRACT FROM AUTHOR]

Measurement of contamination of marine and naval diesel fuels (arising from product mixing or adulteration) with biodiesel or fatty acid methyl esters can be problematic, especially at very low levels. A suitable solution for this task for trace amounts of individual fatty acid methyl esters with resolution and quantification can be achieved by using a multidimensional gas chromatographic approach with electron and chemical ionization mass spectrometric detection. A unique column set comprising a 100mmethyl-siloxane nonpolar first dimension column and high-temperature ionic liquid column in the second dimension enabled identification of individual fatty acid methyl esters at below the lowest concentrations required to be reported in a diesel fuel matrix. Detection limits for individual fatty acid methyl esters compounds ranged from 0.5 to 5.0 mg/L, with excellent linearity up to 5000 mg/L and repeatability of the method from 1.3 to 3.2%. The method was applied to the analysis of diesel fuel samples with suspected biodiesel contamination. Contamination at 568 mg/L was calculated for an unknown sample and interpretation of the results permitted the determination of a likely source of the contamination. [ABSTRACT FROM AUTHOR]

Background The optimal timing of cholecystectomy for patients admitted with acute gallbladder pathology is unclear. Some studies have shown that emergency cholecystectomy during the index admission can reduce length of hospital stay with similar rates of conversion to open surgery, complications and mortality compared with a 'delayed' operation following discharge. Others have reported that cholecystectomy during the index acute admission results in higher morbidity, extended length of stay and increased costs. This study examined the cost-effectiveness of emergency versus delayed cholecystectomy for acute benign gallbladder disease. Methods Using data from a prospective population-based cohort study examining the outcomes of cholecystectomy in the UK and Ireland, a model-based cost-utility analysis was conducted from the perspective of the UK National Health Service, with a 1-year time horizon for costs and outcomes. Probabilistic sensitivity analysis was used to investigate the impact of parameter uncertainty on the results obtained from the model. Results Emergency cholecystectomy was found to be less costly (£4570 versus £4720; €5484 versus €5664) and more effective (0·8868 versus 0·8662 QALYs) than delayed cholecystectomy. Probabilistic sensitivity analysis showed that the emergency strategy is more than 60 per cent likely to be cost-effective across willingness-to-pay values for the QALY from £0 to £100 000 (€0-120 000). Conclusion Emergency cholecystectomy is less costly and more effective than delayed cholecystectomy. This approach is likely to be beneficial to patients in terms of improved health outcomes and to the healthcare provider owing to the reduced costs. [ABSTRACT FROM AUTHOR]

Background: Small bowel obstruction is a common surgical emergency, and is associated with high levels of morbidity and mortality across the world. The literature provides little information on the conservatively managed group. The aim of this study was to describe the burden of small bowel obstruction in the UK. Methods: This prospective cohort study was conducted in 131 acute hospitals in the UK between January and April 2017, delivered by trainee research collaboratives. Adult patients with a diagnosis of mechanical small bowel obstruction were included. The primary outcome was in‐hospital mortality. Secondary outcomes included complications, unplanned intensive care admission and readmission within 30 days of discharge. Practice measures, including use of radiological investigations, water soluble contrast, operative and nutritional interventions, were collected. Results: Of 2341 patients identified, 693 (29·6 per cent) underwent immediate surgery (within 24 h of admission), 500 (21·4 per cent) had delayed surgery after initial conservative management, and 1148 (49·0 per cent) were managed non‐operatively. The mortality rate was 6·6 per cent (6·4 per cent for non‐operative management, 6·8 per cent for immediate surgery, 6·8 per cent for delayed surgery; P = 0·911). The major complication rate was 14·4 per cent overall, affecting 19·0 per cent in the immediate surgery, 23·6 per cent in the delayed surgery and 7·7 per cent in the non‐operative management groups (P < 0·001). Cox regression found hernia or malignant aetiology and malnutrition to be associated with higher rates of death. Malignant aetiology, operative intervention, acute kidney injury and malnutrition were associated with increased risk of major complication. Conclusion: Small bowel obstruction represents a significant healthcare burden. Patient‐level factors such as timing of surgery, acute kidney injury and nutritional status are factors that might be modified to improve outcomes. [ABSTRACT FROM AUTHOR]

Background The aims of this prospective population-based cohort study were to identify the patient and hospital characteristics associated with emergency cholecystectomy, and the influences of these in determining variations between hospitals. Methods Data were collected for consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing the performance of emergency cholecystectomy were analysed by means of multilevel, multivariable logistic regression modelling using a two-level hierarchical structure with patients (level 1) nested within hospitals (level 2). Results Data were collected on 4744 cholecystectomies from 165 hospitals. Increasing age, lower ASA fitness grade, biliary colic, the need for further imaging (magnetic retrograde cholangiopancreatography), endoscopic interventions (endoscopic retrograde cholangiopancreatography) and admission to a non-biliary centre significantly reduced the likelihood of an emergency cholecystectomy being performed. The multilevel model was used to calculate the probability of receiving an emergency cholecystectomy for a woman aged 40 years or over with an ASA grade of I or II and a BMI of at least 25·0 kg/m2, who presented with acute cholecystitis with an ultrasound scan showing a thick-walled gallbladder and a normal common bile duct. The mean predicted probability of receiving an emergency cholecystectomy was 0·52 (95 per cent c.i. 0·45 to 0·57). The predicted probabilities ranged from 0·02 to 0·95 across the 165 hospitals, demonstrating significant variation between hospitals. Conclusion Patients with similar characteristics presenting to different hospitals with acute gallbladder pathology do not receive comparable care. [ABSTRACT FROM AUTHOR]

Background The aim was to describe the management of benign gallbladder disease and identify characteristics associated with all-cause 30-day readmissions and complications in a prospective population-based cohort. Methods Data were collected on consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing all-cause 30-day readmissions and complications were analysed by means of multilevel, multivariable logistic regression modelling using a two-level hierarchical structure with patients (level 1) nested within hospitals (level 2). Results Data were collected on 8909 patients undergoing cholecystectomy from 167 hospitals. Some 1451 cholecystectomies (16·3 per cent) were performed as an emergency, 4165 (46·8 per cent) as elective operations, and 3293 patients (37·0 per cent) had had at least one previous emergency admission, but had surgery on a delayed basis. The readmission and complication rates at 30 days were 7·1 per cent (633 of 8909) and 10·8 per cent (962 of 8909) respectively. Both readmissions and complications were independently associated with increasing ASA fitness grade, duration of surgery, and increasing numbers of emergency admissions with gallbladder disease before cholecystectomy. No identifiable hospital characteristics were linked to readmissions and complications. Conclusion Readmissions and complications following cholecystectomy are common and associated with patient and disease characteristics. [ABSTRACT FROM AUTHOR]

Recent progress using geometry in the design of efficient Markov chain Monte Carlo (MCMC) algorithms have shown the effectiveness of the Fisher Riemannian structure. Furthermore, the theory of the underlying geometry of spaces of statistical models has made an important breakthrough by extending the classical theory on exponential families to their closures, the so-called extended exponential families. This paper looks at the underlying geometry of the Fisher information, in particular its limiting behaviour near boundaries, which illuminates the excellent behaviour of the corresponding geometric MCMC algorithms. Further, the paper shows how Fisher geodesics in extended exponential families smoothly attach the boundaries of extended exponential families to their relative interior. We conjecture that this behaviour could be exploited for trans-dimensional MCMC algorithms. [ABSTRACT FROM AUTHOR]

Ecological studies about marine benthic communities received a major leap from the application of a variety of non-destructive sampling and mapping techniques based on underwater image and video recording. The well-established scientific diving practice consists in the acquisition of single path or 'round-trip' over elongated transects, with the imaging device oriented in a nadir looking direction. As it may be expected, the application of automatic image processing procedures to data not specifically acquired for 3D modelling can be risky, especially if proper tools for assessing the quality of the produced results are not employed. This paper, born from an international cooperation, focuses on this topic, which is of great interest for ecological and monitoring benthic studies in Antarctica. Several video footages recorded from different scientific teams in different years are processed with an automatic photogrammetric procedure and salient statistical features are reported to critically analyse the derived results. As expected, the inclusion of oblique images from additional lateral strips may improve the expected accuracy in the object space, without altering too much the current video recording practices. [ABSTRACT FROM AUTHOR]

B Correction: World J Surg (2019) 43:1928-1934 b https://doi.org/10.1007/s00268-019-04981-5 Since the publication of this work, S. Kanavati has changed their name from O. Kanavati. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. [Extracted from the article]

Mammography challenged [ABSTRACT FROM AUTHOR]

A new class of local mixture models called local scale mixture models is introduced. This class is particularly suitable for the analysis of mixtures of the exponential distribution. The affine structure revealed by specific asymptotic expansions is the motivation for the construction of these models. They are shown to have very nice statistical properties which are exploited to make inferences in a straightforward way. The effect on inference of a new type of boundaries, called soft boundaries, is analyzed. A simple simulation study shows the applicability of this type of models. [ABSTRACT FROM AUTHOR]

Rutherford backscattering spectrometry (RBS) and related techniques have long been used to determine the elemental depth profiles in films a few nanometres to a few microns thick. However, although obtaining spectra is very easy, solving the inverse problem of extracting the depth profiles from the spectra is not possible analytically except for special cases. It is because these special cases include important classes of samples, and because skilled analysts are adept at extracting useful qualitative information from the data, that ion beam analysis is still an important technique. We have recently solved this inverse problem using the simulated annealing algorithm. We have implemented the solution in the `IBA DataFurnace' code, which has been developed into a very versatile and general new software tool that analysts can now use to rapidly extract quantitative accurate depth profiles from real samples on an industrial scale. We review the features, applicability and validation of this new code together with other approaches to handling IBA (ion beam analysis) data, with particular attention being given to determining both the absolute accuracy of the depth profiles and statistically accurate error estimates. We include examples of analyses using RBS, non-Rutherford elastic scattering, elastic recoil detection and non-resonant nuclear reactions. High depth resolution and the use of multiple techniques simultaneously are both discussed. There is usually systematic ambiguity in IBA data and Butler's example of ambiguity (1990 Nucl. Instrum. Methods B 45 160–5) is reanalysed. Analyses are shown: of evaporated, sputtered, oxidized, ion implanted, ion beam mixed and annealed materials; of semiconductors, optical and magnetic multilayers, superconductors, tribological films and metals; and of oxides on Si, mixed metal silicides, boron nitride, GaN, SiC, mixed metal oxides, YBCO and polymers. [ABSTRACT FROM AUTHOR]

Vancouver is located in a temperate rain forest surrounded by mountains and water. Indigenous communities, including the Nations whose homelands the city occupies, have recognized that the abundance of this place can build healthy communities for many generations. But contemporary Vancouver is not a healthy city for all. Since 2014, Vancouver has adopted a Healthy City Strategy, a master social sustainability plan to address inequities in the social determinants of health at a population scale. This includes a number of population health targets and indicators. However, implementation has been slow, with substantive integration of health into policy not yet achieved. With support from the Partnership for Healthy Cities, we have translated the Healthy City Strategy’s indicators into an online dashboard, including disaggregated local data. In addition to public accountability, this tool enables data to be a platform for aligning city policy, action and investment toward common health outcomes. In parallel, we are also piloting more community-generated approaches to health data and indicators, with a focus on co-creating health indicators with Indigenous communities. Preliminary results have shown improvement in collaboration across city departments, leading to increased focus on upstream, preventive work. The dashboard is enabling frameworks for funding and working with the social service sector toward common health goals. Engagement efforts have shown the continued importance of a holistic strategy for health that is co-created with community knowledge and priorities. These interventions must be sustained and integrated into ongoing work. The technical work of developing the dashboard contributes to city-wide efforts toward data monitoring and reporting. Data has shown to be an important tool for beginning conversations, but sharing data about health inequities experienced by communities must be matched with an ongoing commitment to engagement and co-creation. Key messages: Population health data can be leveraged through interactive tools to better integrate and align city policies, plans and investments to address the social determinants of health. Engaging and co-creating policy with communities supports upstream, preventive action on health inequities. [ABSTRACT FROM AUTHOR]

A green sampling approach by direct injection of ionic liquid (IL) solvent containing a variety of analytes using programmable temperature vaporisation (PTV) injection with gas chromatography (GC) is presented. The method was developed using test mixtures of n-alkanes, n-alcohols and polyaromatic compounds, whilst back extraction of isolated compounds from the IL with organic solvent is not required. In the final method, 2 μL of IL, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide containing analytes, was diluted to different volumes (ranging from 10 to 70%) with solvent then injected into the system. Several PTV injector parameters were investigated to ensure analyte volatilisation and transfer into the GC column. Concentration calibration curves (10-150 μg mL-1 and 10-100 μg mL-1 for n-alkanes and n-alcohols, respectively) were constructed, and showed addition of IL increased the peak area of each analyte, with good precision, and acceptable linearity with correlation coefficient, r² > 0.93. This method was successfully applied in analysis of a polynuclear aromatic hydrocarbons (PAHs) mixture, with addition of IL in the mixture and suitable operation of the PTV injector. The method was also applied to eucalyptus leaf essential oil compounds as a test sample in a single drop microextraction experiment. [ABSTRACT FROM AUTHOR]

Clomipramine was used to treat 14 patients with panic attacks. Diagnosis was made according Lo DSM-III criteria for agoraphobia with panic attacks or panic disorder uncomplicated. An open evaluation of the drug over an 8-week treatment period was conducted. A total of 10 patients completed the study. Clomipramine was effective in reducing the mean number of panic attacks, the greatest response being observed in the first 2 weeks of treatment. Findings on all outcome measures showed that clomipramine was also effective in alleviating depression secondary to panic attacks, non-specific aspects of anxiety and improving phobic avoidance. There was a suggestion that responders to treatment received tower doses of clomipramine than non-responders. Further studies are required to evaluate this issue and the role of clomipramine in the treatment or panic disorders. [ABSTRACT FROM AUTHOR]

Purpose: Incisional hernia is a common long-term complication after laparotomy. This study investigated whether prophylactic mesh reinforcement of laparotomy reduced the rate of incisional hernia, with emphasis on trial design and quality. Methods: A systematic review of published literature was performed for studies comparing incisional hernia presence following conventional closure or prophylactic mesh reinforcement. Studies were assessed using the Cochrane Risk of Bias Tool, the Jadad score and the Newcastle Ottawa Scale (NOS). The primary endpoint was incisional hernia, assessed by meta-analysis. Results: Seven studies [four randomised controlled trials (RCTs) and three prospective trials] included 588 patients; 262 received mesh reinforcement. All studies included elective patients at high risk of incisional hernia. Six incorporated a polypropylene mesh and one a biologic mesh. Four studies were judged high quality by NOS and two of four RCTs were at low risk of bias, although overall outcome assessment from all studies was either poor or mediocre. Mesh significantly reduced the rate of incisional hernia [odds ratio (OR) 0.15, p < 0.001]; the same effect was seen in RCTs only (OR 0.17, p < 0.001). A borderline increase of seroma seen with a fixed effect model (OR 1.82, p = 0.050) was not seen with a random effect model (OR 1.86, p = 0.210, I = 45 %). Conclusion: Mesh reinforcement of laparotomy significantly reduced the rate of incisional hernia in high-risk patients. However, poor assessment of secondary outcomes limits applicability; routine placement in all patients cannot yet be recommended. More evidence regarding the rates of adverse events, cost-benefits and quality of life are needed. [ABSTRACT FROM AUTHOR]

Age validation of bluenose Hyperoglyphe antarctica was sought using the independent bomb chronometer procedure. Radiocarbon (C) levels were measured in core micro-samples from 12 otoliths that had been aged using a zone count method. The core C measurement for each fish was compared with the value on a surface water reference curve for the calculated birth year of the fish. There was good agreement, indicating that the line-count ageing method described here is not substantially biased. A second micro-sample was also taken near the edge of nine of the otolith cross-sections to help define a bomb-carbon curve for waters deeper than 200-300 m. There appears to be a 10 to 15 year lag in the time it takes the C to reach the waters where adult H. antarctica are concentrated. The maximum estimated age of this species was 76 years, and females grow significantly larger than males. Von Bertalanffy growth curves were estimated, and although they fit the available data reasonably well, the lack of aged juvenile fish results in the K and t parameters being biologically meaningless. Consequently, curves that are likely to better represent population growth were estimated by forcing t to be −0·5. [ABSTRACT FROM AUTHOR]

Comprehensive multidimensional gas chromatography (GC×GC) is a powerful separation technique. One of the features of this technique is that it offers separations with more apparent structure than that offered by conventional one-dimensional GC (1-D GC). While some previous studies have alluded to this structure, and used structured retention patterns for some simple classifications, the topic of structured retention in GC×GC has not been studied in any great detail. Using the separation of fatty acid methyl esters (FAME) on both nonpolar/polar and polar/nonpolar column sets, the interaction between the separation dimensions and the sample dimensions is explored here. The GC×GC separation of a series of compounds is presented as a projection of the sample from sample space, a p-dimensional space with dimensions defined by the dimensionality of the sample, into separation space: for GC×GC, a two-dimensional plane passing through the sample space in an orientation defined by the separation conditions. Using this conceptual model and some a priori knowledge of the sample, it is shown how the image of the sample in the separation space can be used to construct an image of the sample in alternate dimensions, such as second dimension retention factor (2k) vs. chain length in the case of FAME. These projections into alternate dimensions should facilitate the interpretation of the complex patterns found within the GC×GC chromatogram for the identification and classification of compounds. [ABSTRACT FROM AUTHOR]

The ethylene tar and mixtures of ethylene tar with other petrochemical by-products were used as collectors for coal flotation. The results showed that the 1# compound collector was better than kerosene in terms of selectivity and collectibility for coal flotation. When the collector dosage was 1500 g/t, the yield of clean coal using the 1# compound collector increased by 4.05%, and the reduction in ash content was 0.36% lower compared to using kerosene. The mechanism of action of 1# compound collector on the coal surface was analyzed in combination with GC-MS tests and FTIR tests. The 1# compound collector contains more aromatics, olefins and heteropolar substances than kerosene. When the aromatics in the 1# compound collector interact with the nonpolar sites on the coal surface via π–π stacking interactions, some of the polar sites sandwiched between the aromatic compound molecules are covered. The olefins contained therein engage with the nonpolar sites on the surface experiences interactions attributable to van der Waals forces. The oxygenated functional groups of alcohols, acids, esters and carbonyl compounds engage with the polar sites on the surface of the particles through hydrogen bonding. [ABSTRACT FROM AUTHOR]

Many colonial anthozoans are ecosystem engineers and contribute to creating intricate benthic communities that often harbor high levels of marine biodiversity. Here, we report on an extraordinarily large antipatharian colony observed on the West Mariana Ridge in the Northwest Pacific. Based on colony form, morphological analyses, and DNA barcoding results, we identified the colony as Leiopathes cf. annosa. From in situ observations, we estimate the size of the colony as approximately 308 cm in height and 441 cm in width, with a central stem of 28 cm in diameter. If growth rates of Leiopathes species in this region of the Pacific Ocean are similar to those previously reported from Hawaii, this colony may be approximately 7000 years old, placing it among the longest-lived marine organisms reported. Seamounts in this region and such large anthozoan colonies should be targeted for more biodiversity investigation and future conservation. [ABSTRACT FROM AUTHOR]

Background: Hydatid disease is a zoonotic disease caused by the intermediate stage of dog tapeworm Echinococcus granulosus. Objectives: The study investigated the prevalence of hydatid cysts and the risk factors in cattle slaughtered at the Bishoftu municipal abattoir. It also analyzed the economic loss and community's awareness of this matter. Animals: 480 cattle brought for slaughtering were included in the study. Methods: A cross‐sectional study was conducted from December 2022 to April 2023 in Bishoftu municipal abattoir involving antemortem examination of cattle and postmortem hydatid cyst investigation, assessment of associated economic loss, and community awareness survey. Animals were selected systematically and cysts were investigated using standard meat inspection procedures. Results: 10.4% of the slaughtered cattle were found positive for hydatid cysts, with no statistically significant association with the considered risk factors. From 85 collected cysts, the lungs accounted for 55.3%, the liver for 29.4%, and the remaining 15.3% were from the spleen, kidney, and heart. About 47.1% of the cysts were fertile and 52.9% were infertile, of which, 37.5% were nonviable. In a survey of 100 individuals, 33.0% were unaware of hydatid disease, and 61.0% were unaware that the disease is zoonotic. Annual economic loss due to the case was estimated at 5,444,564.4 ($97,224.4). Conclusion: This study identified hydatid disease as a significant issue in cattle in Bishoftu, indicating the need for preventative and control measurements. Strategies such as deworming, controlling street dogs, establishing standardized abattoirs, and raising public awareness should be applied to alleviate the problem in Bishoftu and nationwide. [ABSTRACT FROM AUTHOR]

Background: There is controversy about the benefit of administering adjuvant therapy to esophageal cancer (EC) patients after preoperative neoadjuvant therapy and surgical treatment. This study aims to investigate the clinical benefit of postoperative adjuvant therapy in EC patients with neoadjuvant therapy and surgery. Materials and methods: The study included EC patients diagnosed from 2007 to 2020 in the Surveillance, Epidemiology, and End Results (SEER) database. Patients who received neoadjuvant therapy (NCRT) were defined as those who underwent neoadjuvant chemotherapy or neoadjuvant radiotherapy before surgery, while patients who received adjuvant therapy (ACRT) were defined as those who underwent adjuvant chemotherapy or adjuvant radiotherapy after surgery. Propensity score matching (PSM) method was employed to establish matched cohorts, and Kaplan-Meier analysis, COX regression model, and Fine-Gray model were used for survival analysis. Results: The study included a total of 5805 EC patients, with 837 (14.4%) in the ACRT group and 4968 (85.4%) in the no-ACRT group. After PSM, a cohort of 1660 patients who received NCRT was enrolled for analysis, with 830 patients in each group. Kaplan-Meier analysis revealed no significant differences between the two groups in terms of median overall survival (OS) (34.0 vs. 36.0 months, p = 0.89) or cancer-specific survival (CSS) (40.0 vs. 49.0 months, p = 0.16). Multivariate Cox models and Fine-Gray models indicated that ACRT was not a predictive factor for OS or CSS (p > 0.05). Subgroup analysis for CSS suggested a protective effect of ACRT in the N2 (Cox model: HR = 0.640, p = 0.090; Fine-Gray model: HR = 0.636, p = 0.081) and the N3 subgroup (Cox model: HR = 0.302, p = 0.018; Fine-Gray model: HR = 0.306, p = 0.034). Conclusions: Only for esophageal cancer patients with a more advanced N stage, postoperative adjuvant therapy after completing neoadjuvant therapy and curative surgical treatment may be beneficial. [ABSTRACT FROM AUTHOR]

Hydrothermal vents have emerged as important sources of iron to seawater, yet only a subset of this iron is soluble and persists long enough to impact the deep-ocean iron inventory. The longevity and solubility of iron in seawater is in part governed by strong organic ligands that are produced by microorganisms and are a part of the ocean's dissolved organic iron-binding ligand pool. Organic ligands have long been recognized to support elevated dissolved iron in hydrothermal vent plumes. Siderophores are one group of microbially produced organic ligands that have especially high binding affinities for iron. Here we present the first direct measurements of siderophore concentrations in hydrothermal vents, which we compare to bulk strong iron-binding ligand concentrations, along a 1700 km section of the Mid-Atlantic Ridge. Siderophores were found in hydrothermal plumes at all sites, with proximity to the vent playing an important role in dictating siderophore type and diversity. The notable presence of amphiphilic siderophores may point to microbial utilization of siderophores to access particulate hydrothermal iron and the exchange of dissolved and particulate iron. The tight coupling between strong ligands and dissolved iron within neutrally buoyant plumes across distinct hydrothermal environments, as well as the presence of dissolved siderophores with siderophore-producing microbial genera, suggests that biological production of ligands influences iron chemistry in hydrothermal systems. [ABSTRACT FROM AUTHOR]

This study focused on the formulation, electron beam (e-beam) crosslinking, and characterisation of hydrogels enriched with lavender oil (LO) to enhance their structural and functional properties for biomedical applications. Stable hydrogels were synthesised using water-soluble polymers and suitable ratios of Tween 80 and Isopropyl alcohol (IPA) as surfactant and co-surfactant, respectively, via e-beam irradiation at doses up to 70 kGy. The most effective crosslinking was achieved with a radiation dose of 30 kGy, depending on the concentrations of surfactants and LO. LO-enriched hydrogels exhibited enhanced superabsorbent swelling (7700% to 18,000%) and faster equilibrium rates than the control hydrogel. Structural analysis revealed a flexible spongiform porous architecture with larger mesh sizes (156 nm to 246 nm) and adequate elastic moduli (130 to 308 Pa). Degradation tests aligned with swelling data, demonstrating a degradation rate of 12% after 35 days, indicating an appropriate balance of stability and degradation. These findings suggest that e-beam technology, in conjunction with LO and surfactant addition, can effectively tailor hydrogel properties for biomedical applications, making them promising candidates for further research in wound care, drug delivery systems, and other biological applications. [ABSTRACT FROM AUTHOR]

Active dendritic integrative mechanisms such as regenerative dendritic spikes enrich the information processing abilities of neurons and fundamentally contribute to behaviorally relevant computations. Dendritic Ca2+ spikes are generally thought to produce plateau-like dendritic depolarization and somatic complex spike burst (CSB) firing, which can initiate rapid changes in spatial coding properties of hippocampal pyramidal cells (PCs). However, here we reveal that a morpho-topographically distinguishable subpopulation of rat and mouse hippocampal CA3PCs exhibits compound apical dendritic Ca2+ spikes with unusually short duration that do not support the firing of sustained CSBs. These Ca2+ spikes are mediated by L-type Ca2+ channels and their time course is restricted by A-and M-type K+ channels. Cholinergic activation powerfully converts short Ca2+ spikes to long-duration forms, and facilitates and prolongs CSB firing. We propose that cholinergic neuromodulation controls the ability of a CA3PC subtype to generate sustained plateau potentials, providing a state-dependent dendritic mechanism for memory encoding and retrieval. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) represent a fusion of compelling porous structures, alluring physical and chemical attributes, and extensive possibilities for application. The inherent capability of employing these organic constituents has paved the path for the construction of MOFs, permitting imaginative pre-design and post-synthetic adjustments through apt reactions. This adaptability not only enriches the structural variety of MOFs but also uncovers pathways for customizing their characteristics to align with precise application needs. In this context, click chemistry has emerged as a potent and resilient tool in the creation and modification of diverse functional materials, with a promising application in MOF structures. These MOF architectures undergo postsynthetic modifications through the application of "click" chemistry. This approach, characterized by its efficiency and selectivity, proves instrumental in tailoring and enhancing the properties of MOFs, thereby expanding their utility across a spectrum of scientific and industrial applications. Herein, we illuminate recent MOF structures achieved through the postsynthetic application of "click" chemistry. Our exploration delves into the forefront of strategies propelling the postsynthetic modification process, with a dedicated focus on the structural complexities, synthesis methodologies, and the prospective applications of these modified MOF architectures. Our intention is to actively contribute to the continuous discourse on applications of click chemistry in the development of MOF architectures, encouraging scientists to dedicate their expertise and efforts towards the advancement of these multifunctional materials. [ABSTRACT FROM AUTHOR]

Minimally invasive laparoscopic cholecystectomy is among the most frequently performed abdominal surgeries. Bile duct injury is a significative complication that occurs in about 0.2–0.3% of open procedures and 0.5% of laparoscopic surgeries, with concomitant vasculobiliary injuries in 12–61% of cases. Most of these lesions occurs during challenging severe cholecystitis where the intense inflammation obscures the hepatocystic anatomy. In this case a bailout strategy such as a subtotal cholecystectomy should be considered. Subtotal cholecystectomy is a surgical technique performed to remove a portion of the gallbladder while leaving part of it behind. In such complex cholecystectomies, surgeons should be aware of this technique, and subtotal cholecystectomy should be part of their surgical armamentarium. We aim to familiarize surgeons with bailout techniques like subtotal cholecystectomy and gallbladder emptying for challenging acute cholecystectomy cases to reduce the risk of vasculobiliary injury. This multimedia article provides, a comprehensive step-by-step overview of the different possible minimally invasive subtotal cholecystectomy procedures, we outline five distinct techniques for conducting subtotal cholecystectomy, including some tips and tricks and demonstrates the usefulness of a minimally invasive approach. Finally, we emphasize the importance of carefully choosing between laparoscopic and robotic approaches and suggests using adjunctive tools, such as preoperative indocyanine green, to better identify common bile duct anatomy. [ABSTRACT FROM AUTHOR]

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Interstitial lung diseases (ILDs) include a variety of inflammatory and fibrotic pulmonary conditions. This study employs high‐resolution metabolomics (HRM) to explore plasma metabolites and pathways across ILD phenotypes, including non‐fibrotic ILD, idiopathic pulmonary fibrosis (IPF), and non‐IPF fibrotic ILD. The study used 80 plasma samples for HRM, and involved linear trend and group‐wise analyses of metabolites altered in ILD phenotypes. We utilized limma one‐way ANOVA and mummichog algorithms to identify differences in metabolites and pathways across ILD groups. Then, we focused on metabolites within critical pathways, indicated by high pathway overlap sizes and low p‐values, for further analysis. Targeted HRM identified putrescine, hydroxyproline, prolyl‐hydroxyproline, aspartate, and glutamate with significant linear increases in more fibrotic ILD phenotypes, suggesting their role in ILD fibrogenesis. Untargeted HRM highlighted pathway alterations in lysine, vitamin D3, tyrosine, and urea cycle metabolism, all associated with pulmonary fibrosis. In addition, methylparaben level had a significantly increasing linear trend and was higher in the IPF than fibrotic and non‐ILD groups. This study highlights the importance of specific amino acids, metabolic pathways, and xenobiotics in the progression of pulmonary fibrosis. [ABSTRACT FROM AUTHOR]

Background: The demand for nursing professionals with advanced education and specialized knowledge is growing, which encourages nursing undergraduates to pursue postgraduate studies. Therefore, an in-depth investigation into the barriers and facilitators affecting the motivation of nursing undergraduates to take postgraduate entrance exams was necessary. This may provide more targeted recommendations for the formulation of relevant policies and the provision of student support. The purpose of this study is to explore the barriers and facilitators affecting the motivation of nursing undergraduates for postgraduate entrance examination. Methods: Data for this study were collected from in-depth semi-structured interviews with 15 nursing undergraduates from Nantong University between October and December 2023. Thematic analysis was employed to analyze the data. Results: Four barriers were identified, including study pressure and internship fatigue, self-doubt and fear of failure, employment pressure, and lack of information and resources. Four facilitators were also identified, including the desire to upgrade academic qualifications and professional skills, career development and transition, escaping clinical work and delaying employment, as well as the power of role models, and social support. Conclusions: The findings may help nursing undergraduates navigate the path to postgraduate entrance exams more effectively and ultimately succeed in their studies and future careers. The study underscores the importance of addressing these barriers and leveraging these facilitators to support the holistic development of nursing students. [ABSTRACT FROM AUTHOR]

Rate coefficients for the reactions of OH radicals with C 3 –C 11 alkanes were determined using the multivariate relative-rate technique. A total of 25 relative-rate coefficients at room temperature and 24 Arrhenius expressions in the temperature range of 273–323 K were obtained. Notably, a new room temperature relative-rate coefficient for 3-methylheptane that had not been previously reported was determined, and the obtained kOH value (in units of 10-12 cm 3 molec. -1 s -1) was 7.71 ± 0.35. Interestingly, whilst results for n-alkanes agreed well with available structure–activity relationship (SAR) calculations of Kwok and Atkinson (1995), Neeb (2000), Wilson et al. (2006), Jenkin et al. (2018), and McGillen et al. (2020), the three cycloalkanes (cyclopentane, methylcyclopentane, cyclohexane) and one branched alkane (2,2,4-trimethylpentane) were found to be less reactive than predicted by the SAR approach. Conversely, the SAR estimates for 2,3-dimethylbutane were approximately 25 % lower than the experimental values, with the exception of those estimated by the Wilson group, highlighting that there may be additional factors that govern the reactivity of highly branched alkanes that are not captured by current SAR techniques. Arrhenius expressions (in units of cm 3 molec. -1 s -1) for the reactions of various branched alkanes with OH radicals were determined for the first time: 2-methylheptane, 1.37±0.48×10-11exp⁡-209±100/T , and 3-methylheptane, 3.54±0.45×10-11exp⁡-374±49/T. The reactivity relation of saturated alkanes with OH radicals and chlorine atoms was obtained: log⁡10k(Cl+alkanes)=0.569×log⁡10k(OH+alkanes)-3.111 (R2 = 0.86). In addition, the rate coefficients for the 24 previously studied OH + alkanes reactions were consistent with existing literature values, demonstrating the reliability and efficiency of this method for the simultaneous investigation of gas-phase reaction kinetics. [ABSTRACT FROM AUTHOR]

An innovative SPME head space GC–MS method, in cooling mode, using a fully automated routine, was developed to detect 2-phenyl-2-propanol, a representative urinary metabolite of cumene. Following an acid hydrolysis and derivatization step with lowered quantities of reagents, acetic anhydride and pyridine, a 30 μm polydimethylsiloxane SPME fiber was used to sample derivatized 2-phenyl-2-propanol, such as benzenemethanol,α,α-dimethyl-acetate, from the headspace. Performances of the method, optimized through experimental design, provide an LOD of 0.034 mg/L and an LOQ 0.10 mg/L, with a short sampling time necessary per sample. The method, developed on standard solutions, will be applied to both occupationally exposed and non-exposed populations. [ABSTRACT FROM AUTHOR]

The synthesis of DNA, as measured by the incorporation of [3H]- thymidine into the nuclei of cells of cultured explants of rabbit spleen, has been studied and correlated with estimation of DNA content of these nuclei using Feulgen densitometry, with and without colcemid arrest. Observations of the proportion of nuclei labelled with [3H] thymidine and their DNA content indicated that many cells were incorporating this precursor for DNA synthesis without the concomitant increases in DNA expected of cells in division cycle. Colcemid arrest failed to produce the changes in DNA content expected of a cell population as rapidly dividing as the labelling kinetics suggested. The results indicated that [3H] thymidine-labelled material, possibly DNA, was being transferred between cells and this accounted for the increased labelling index seen after pulsing with [3H] thymidine. The suppression of [3H] thymidine uptake by hydroxyurea indicated that this was not repair synthesis of damaged DNA.

The study discusses the photodegradation and photochemistry of the organophosphorus pesticide parathion. It states that unpurified parathion and paraoxon were observed to better understand its photoreactions and the environmental effects of pesticides. It states that the concentration spectrum of parathion in methanol indicated a impregnable but structureless band.

A patient with a 14 year history of sarcoidosis developed a progressive left cerebral hemisphere lesion. The clinical diagnosis of progressive multifocal leucoencephalopathy was confirmed by brain biopsy and remission occurred after treatment with cytosine arabinoside. [ABSTRACT FROM AUTHOR]

Nucleic acid‐based vaccines allow scalable, rapid, and cell‐free vaccine production in response to an emerging disease such as the current COVID‐19 pandemic. Here, we objected to the design of a multiepitope mRNA vaccine against the structural proteins of SARS‐CoV‐2. Through an immunoinformatic approach, promising epitopes were predicted for the spike (S), envelope (E), membrane (M), and nucleocapsid (N) proteins. Fragments rich in overlapping epitopes were selected based on binding affinities with HLA classes I and II for the specific presentation to B and T lymphocytes. Two constructs were designed by fusing the fragments in different arrangements via GG linkers. Construct 1 showed better structural properties and interactions with toll‐like receptor 2 (TLR‐2), TLR‐3, and TLR‐4 during molecular docking and dynamic simulation. A 50S ribosomal L7/L12 adjuvant was added to its N‐terminus to improve stability and immunogenicity. The final RNA sequence was used to design a trans‐amplifying RNA (taRNA) vaccine in a split‐vector system. It consists of two molecules: a nonreplicating RNA encoding a trans‐acting replicase to amplify the second one, a trans‐replicon (TR) RNA encoding the vaccine protein. Overall, the immune response simulation detected that activated B and T lymphocytes and increased memory cell formation. Macrophages and dendritic cells proliferated continuously, and IFN‐γ and cytokines like IL‐2 were released highly. [ABSTRACT FROM AUTHOR]

A single-step phenylation at the non-acidic C(sp3)–H bond attached to the heteroatom of ethers and N -Boc-amines has been achieved using photoexcited 4-benzoylpyridine as a hydrogen atom transfer (HAT) catalyst. The design of electron-deficient (trifluoromethylsulfonyl)benzene derivatives, as a phenyl precursor, was critical to realizing the present transformation. Moreover, the DFT calculations indicated that the present transformation proceeds via a concerted homolytic aromatic substitution rather than via a stepwise one involving the formation of a cyclohexadienyl radical intermediate. [ABSTRACT FROM AUTHOR]