bluuebunny/crossref_metadata_2025 huggingface dataset:
Euthanasia in the Netherlands: a claims data cross-sectional study of geographical variation
Authors: Groenewoud A Stef , Atsma Femke , Arvin Mina , Westert Gert P , Boer Theo A
Published: January 2021

Background

The annual incidence of euthanasia in the Netherlands as a percentage of all deaths rose from 1.9% in 1990 to 4.4% in 2017. Scarce literature on regional patterns calls for more detailed insight into the geographical variation in euthanasia and its possible explanations.

Objectives

This paper (1) shows the geographical variation in the incidence of euthanasia over time (2013–2017); (2) identifies the associations with demographic, socioeconomic, preferential and health-related factors; and (3) shows the remaining variation after adjustment and discusses its meaning.

Design, setting and methods

This cross-sectional study used national claims data, covering all healthcare claims during 12 months preceding the death of Dutch insured inhabitants who died between 2013 and 2017. From these claims all euthanasia procedures by general practitioners were selected (85% of all euthanasia cases). Rates were calculated and compared at three levels: 90 regions, 388 municipalities and 196 districts in the three largest Dutch cities. Data on possibly associated variables were retrieved from national data sets. Negative binomial regression analysis was performed to identify factors associated with geographical variation in euthanasia.

Results

There is considerable variation in euthanasia ratio. Throughout the years (2013–2017) the ratio in the three municipalities with the highest incidence was 25 times higher than in the three municipalities with the lowest incidence. Associated factors are age, church attendance, political orientation, income, self-experienced health and availability of voluntary workers. After adjustment for these characteristics a considerable amount of geographical variation remains (factor score of 10), which calls for further exploration.

Conclusion

The Netherlands, with 28 years of legal euthanasia, experiences large-scale unexplained geographical variation in the incidence of euthanasia. Other countries that have legalised physician-assisted dying or are in the process of doing so may encounter similar patterns. The unexplained part of the variation may include the possibility that part of the euthanasia practice may have to be understood in terms of underuse, overuse or misuse.
SECUre: a multicentre survey of the safety of emergency care in UK emergency departments
Authors: Flowerdew Lynsey , Tipping Michelle
Published: January 2021

Introduction

According to safety theory, frontline staff are often best informed to identify problems that threaten safety in their workplace. Surveying emergency department (ED) staff is a straightforward method for investigating risks, identifying solutions and evaluating interventions. This study’s aim was to validate an ED safety questionnaire specifically for use in the UK and provide an overview of safety culture and risks.

Methods

An ED safety questionnaire developed in the USA was modified then validated using 33 RCEM (Royal College of Emergency Medicine) patient safety leads (calculating content validity index). The resulting 39 multiple-choice questionnaire was used in a multicentre survey. 110 participants were randomly selected from each site. A minimum 40% response rate per site reduced non-response bias. Cronbach’s alpha was calculated across five categories as an estimate of reliability. Simple descriptive statistics were used to identify risks or good practice. χ2test compared individual sites’ results with national results to highlight outlier questions (ie, the department’s strengths and weaknesses). χ2was also used to identify significant differences between responses from nurses and doctors.

Results

1060 participants were recruited across 18 sites. Cronbach’s alpha was adequate (0.65 to 0.8). Analysis highlighted risks posed by interruptions, negative effects of targets, deficient mental healthcare (especially compared with critical care) and ED crowding. The study also revealed encouraging safety culture, such as effective doctor–nurse communication, and identified sites that were positive outliers overall or for specific questions. Comparing doctors and nurses’ responses suggests additional support is needed for nursing staff.

Conclusions

This study provides the first step towards assessing ED safety culture and describing risks in the UK. Identifying outlier sites provides opportunities to learn from excellence. Repeat application of the survey will enable monitoring of safety interventions on a local and national level.
The International Federation for Emergency Medicine report on emergency department crowding and access block: A brief summary
Authors: Javidan Arshia P , Hansen Kim , Higginson Ian , Jones Peter , Lang Eddy
Published: January 2021

Objective

To develop comprehensive guidance that captures international impacts, causes and solutions related to emergency department (ED) crowding and access block.

Methods

Emergency physicians representing 15 countries from all International Federation of Emergency Medicine (IFEM) regions composed the Task Force. Monthly meetings were held via video-conferencing software to achieve consensus for report content. The report was submitted and approved by the IFEM Board on June 1, 2020.

Results

A total of 14 topic dossiers, each relating to an aspect of ED crowding, were researched and completed collaboratively by members of the Task Force.

Conclusions

The IFEM report is a comprehensive document intended to be used in whole or by section to inform and address aspects of ED crowding and access block. Overall, ED crowding is a multifactorial issue requiring systems-wide solutions applied at local, regional, and national levels. Access block is the predominant contributor of ED crowding in most parts of the world.
Novel scheme for non-invasive gut bioinformation acquisition with a magnetically controlled sampling capsule endoscope
Authors: Ding Zhen , Wang Weijun , Zhang Kun , Ming Fanhua , Yangdai Tianyi , Xu Tao , Shi Huiying , Bao Yuhui , Yao Hailing , Peng Hangyu , Han Chaoqun , Jiang Weiwei , Liu Jun , Hou Xiaohua , Lin Rong
Published: January 2021

Objective

Intestinal flora and metabolites are associated with multiple systemic diseases. Current approaches for acquiring information regarding microbiota/metabolites have limitations. We aimed to develop a precise magnetically controlled sampling capsule endoscope (MSCE) for the convenient, non-invasive and accurate acquisition of digestive bioinformation for disease diagnosis and evaluation.

Design

The MSCE and surgery were both used for sampling both jejunal and ileal GI content in the control and antibiotic-induced diarrhoea groups. The GI content was then used for microbiome profiling and metabolomics profiling.

Results

Compared with surgery, our data showed that the MSCE precisely acquired data regarding the intestinal flora and metabolites, which was effectively differentiated in different intestinal regions and disease models. Using MSCE, we detected a dramatic decrease in the abundance of Bacteroidetes, Patescibacteria and Actinobacteria and hippuric acid levels, as well as an increase in the abundance of Escherichia–Shigella and the 2-pyrrolidinone levels were detected in the antibiotic-induced diarrhoea model by MSCE. MSCE-mediated sampling revealed specific gut microbiota/metabolites including Enterococcus, Lachnospiraceae, acetyl-L-carnitine and succinic acid, which are related to metabolic diseases, cancers and nervous system disorders. Additionally, the MSCE exhibited good sealing characteristics with no contamination after sampling.

Conclusions

We present a newly developed MSCE that can non-invasively and accurately acquire intestinal bioinformation via direct visualization under magnetic control, which may further aid in disease prevention, diagnosis, prognosis and treatment.
Modelling the cascade of biomarker changes in GRN-related frontotemporal dementia
Authors: Panman Jessica L , Venkatraghavan Vikram , van der Ende Emma L , Steketee Rebecca M E , Jiskoot Lize C , Poos Jackie M , Dopper Elise G P , Meeter Lieke H H , Donker Kaat Laura , Rombouts Serge A R B , Vernooij Meike W , Kievit Anneke J A , Premi Enrico , Cosseddu Maura , Bonomi Elisa , Olives Jaume , Rohrer Jonathan D , Sánchez-Valle Raquel , Borroni Barbara , Bron Esther E , Van Swieten John C , Papma Janne M , Klein Stefan
Published: January 2021

Objective

Progranulin-related frontotemporal dementia (FTD-GRN) is a fast progressive disease. Modelling the cascade of multimodal biomarker changes aids in understanding the aetiology of this disease and enables monitoring of individual mutation carriers. In this cross-sectional study, we estimated the temporal cascade of biomarker changes for FTD-GRN, in a data-driven way.

Methods

We included 56 presymptomatic and 35 symptomatic GRN mutation carriers, and 35 healthy non-carriers. Selected biomarkers were neurofilament light chain (NfL), grey matter volume, white matter microstructure and cognitive domains. We used discriminative event-based modelling to infer the cascade of biomarker changes in FTD-GRN and estimated individual disease severity through cross-validation. We derived the biomarker cascades in non-fluent variant primary progressive aphasia (nfvPPA) and behavioural variant FTD (bvFTD) to understand the differences between these phenotypes.

Results

Language functioning and NfL were the earliest abnormal biomarkers in FTD-GRN. White matter tracts were affected before grey matter volume, and the left hemisphere degenerated before the right. Based on individual disease severities, presymptomatic carriers could be delineated from symptomatic carriers with a sensitivity of 100% and specificity of 96.1%. The estimated disease severity strongly correlated with functional severity in nfvPPA, but not in bvFTD. In addition, the biomarker cascade in bvFTD showed more uncertainty than nfvPPA.

Conclusion

Degeneration of axons and language deficits are indicated to be the earliest biomarkers in FTD-GRN, with bvFTD being more heterogeneous in disease progression than nfvPPA. Our data-driven model could help identify presymptomatic GRN mutation carriers at risk of conversion to the clinical stage.
Impact of statin on long-term outcome among patients with end-stage renal disease with acute myocardial infarction (AMI): a nationwide case–control study
Authors: Kuo Feng-You , Huang Wei-Chun , Tang Pei-Ling , Cheng Chin-Chang , Chiang Cheng-Hung , Lin Hsiao-Chin , Chuang Tzu-Jung , Wann Shue-Ren , Mar Guang-Yuan , Liu Chun-Peng , Cheng Juei-Tang , Wu Ming-Chang
Published: January 2021

Background

Use of statin has been associated with reduced risk of cardiovascular diseases events and mortality. However, in patients with end-stage renal disease (ESRD), the protective effects of statin are controversial. To evaluate the impact of chronic statin use on clinical outcomes of patients with acute myocardial infarction (AMI) with ESRD.

Methods

We enrolled 8056 patients with ESRD who were initially diagnosed and admitted for first AMI from Taiwan’s National Health Insurance Research Database. Of which, 2134 patients underwent statin therapy. We randomly selected and use age, sex, hypertension, diabetes mellitus (DM), peripheral vascular diseases (PVD), heart failure (HF), cerebrovascular accidents (CVA), chronic obstructive pulmonary disease, matched with the study group as controls (non-stain user). We compared the effects of statin use in term of all-cause death among patients with AMI with ESRD.

Results

Statin use resulted in a significantly higher survival rate in patients ith AMI with ESRD compared with non-statin users. After adjusted the comorbidities the male patients and patients with DM, PVD, HF and CVA had lower long-term survival rate (all p<0.001). Patients who underwent percutaneous coronary intervention (p<0.001), ACE inhibitors/angiotensin II receptor blockers (p<0.001), β receptor blockers (p<0.001) and statin therapy (p=0.007) had better long-term survival rate. Patients with AMI with ESRD on statin therapy exhibited a significantly lower risk of mortality compared with non-statin users (p<0.0001).

Conclusion

Among patients with ESRD with AMI, statin therapy was associated with reduced all-cause mortality.
Solifenacin-induced acute urticaria and angioedema: a rare adverse effect
Authors: Younas Umer , Shafiq Omar , Mansoor Sahibzada Nasir , Khalil Muhammad Tawab
Published: January 2021

Antimuscarinics are first-line medication for management of overactive bladder with solifenacin being commonly prescribed. Angioedema is the swelling of mucosa and submucosal tissue. There are no published case reports of drug-induced angioedema involving solifenacin. We report a case of a 41-year-old man with spinal cord injury who presented with oedema of face, lips, tongue and associated pruritic urticaria after taking 5 mg of solifenacin. All other possible causes including food allergy, insect bite, hereditary angioedema, use of NSAIDs, ACE inhibitors and antibiotics were ruled out. The temporal association between solifenacin and angioedema and complete resolution of symptoms after discontinuing the drug suggest that solifenacin was the most probable cause of angioedema in our patient.
Enhancing communication between foundation doctors and radiologists: a quality improvement project
Authors: Chuang Yu-Hsiang , Jones Victor , Trail Matthew , Szewczyk-Bieda Magdalena , Nandwani Ghulam Mustafa
Published: January 2021

Facilitating radiological imaging for patients is an essential task for foundation year (FY) doctors. Achieving competence in this task can significantly enhance patient management. We evaluated the confidence and skills of FY doctors in facilitating radiological imaging before and after introduction of formal training. Twenty surgical FYs working at a large teaching hospital were surveyed to evaluate their baseline level of competence in booking and discussing imaging with radiology colleagues. Parameters were measured on a Likert scale, including confidence in discussing requests and satisfaction of their own performance following discussions with radiologists. Eight radiology consultants were surveyed to evaluate their opinions on FYs’ communication and established areas for improvement. A teaching session was then delivered to improve communication skills. Furthermore, Previous investigation results, Answer you need from the scan, Clinical status and story, Crucial: how urgent is the scan, Safety (PACCSS) poster was introduced to remind the FYs of the salient information required when discussing imaging. One month after the intervention, the initial participants were resurveyed. Based on a 10-point Likert scale, the FYs demonstrated a mean improvement in self-reported confidence (2.1±1.1, p<0.01), and in satisfaction of own performance after a discussion (1.7±1.1, p<0.01). We identified deficiencies in surgical FY doctors’ confidence and skills in facilitating radiological imaging. There was a demonstrable benefit with focused training in improving these skills. This could potentially provide significant benefits in patient care and management. Interspecialty communication should be introduced into undergraduate and postgraduate educational curriculum.
Gender and racial trends among neurology residents: an overview
Authors: Maqsood Hamza , Naveed Sadiq , Mohyud Din Chaudhary Amna , Khan Muhammad Taimoor , Khosa Faisal
Published: January 2021

Diversification of academic medicine improves healthcare standards and patient outcomes. Gender and racial inequalities are major challenges faced by the healthcare system. This article reviews the trends of gender and racial disparity among residents of neurology. This retrospective analysis of the annual Accreditation Council for Graduate Medical Education Data Resource Books encompassed all residents at US neurology residency training programmes from the year 2007 to 2018. The representation of women steadily increased, with an absolute increase of 3% from the year 2007 to 2018. Although the absolute change (%) increased for the White race, Asian/Pacific Islander, Black/African Americans, there was a decrease seen in the Hispanic representation in neurology residents from the year 2011 to 2018. There was no change seen for the Native Americans/Alaskans. Our study concluded that gender and racial disparity persists in the recruitment of residents in neurology. This study highlights the need for targeted interventions to address gender and racial disparity among residents of neurology. Further studies are needed to explore etiological factors to address gender and racial disparity.
High-stakes examinations during the COVID-19 pandemic: to proceed or not to proceed, that is the question
Authors: Tan Chee-Kiat , Chua Wei-Ling , Vu Charles Kien-Fong , Chang Jason Pik-Eu
Published: January 2021

The COVID-19 pandemic has disrupted education-related activities, including the conduct of examinations. We review the literature regarding high-stakes examinations during the pandemic, discuss the decision-making process of whether to proceed with a high-stakes examination and share published experiences in conducting high-stakes examinations during the pandemic. We illustrate our own recent experiences of decision-making and conduct of our high-stakes gastroenterology licencing examinations during the height of the COVID-19 pandemic. It is possible to conduct high-stakes examinations virtually during pandemic situations with fidelity and adherence to the established format and standards.
Prognostic value of elevated lactate dehydrogenase in patients with COVID-19: a systematic review and meta-analysis
Authors: Martha Januar Wibawa , Wibowo Arief , Pranata Raymond
Published: January 2021

Purpose

This meta-analysis aimed to evaluate the prognostic performance of elevated lactate dehydrogenase (LDH) in patients with COVID-19.

Methods

A systematic literature search was performed using PubMed, Embase and EuropePMC on 19 November 2020. The outcome of interest was composite poor outcome, defined as a combined endpoint of mortality, severity, need for invasive mechanical ventilation and need for intensive care unit care. Severity followed the included studies' criteria.

Results

There are 10 399 patients from 21 studies. Elevated LDH was present in 44% (34%–53%) of the patients. Meta-regression analysis showed that diabetes was correlated with elevated LDH (OR 1.01 (95% CI 1.00 to 1.02), p=0.038), but not age (p=0.710), male (p=0.068) and hypertension (p=0.969). Meta-analysis showed that elevated LDH was associated with composite poor outcome (OR 5.33 (95% CI 3.90 to 7.31), p<0.001; I2: 77.5%). Subgroup analysis showed that elevated LDH increased mortality (OR 4.22 (95% CI 2.49 to 7.14), p<0.001; I2: 89%). Elevated LDH has a sensitivity of 0.74 (95% CI 0.60 to 0.85), specificity of 0.69 (95% CI 0.58 to 0.78), positive likelihood ratio of 2.4 (95% CI 1.9 to 2.9), negative likelihood ratio of 0.38 (95% CI 0.26 to 0.55), diagnostic OR of 6 (95% CI 4 to 9) and area under curve of 0.77 (95% CI 0.73 to 0.80). Elevated LDH would indicate a 44% posterior probability and non-elevated LDH would in indicate 11% posterior probability for poor prognosis. Meta-regression analysis showed that age, male, hypertension and diabetes did not contribute to the heterogeneity of the analyses.

Conclusion

LDH was associated with poor prognosis in patients with COVID-19.

PROSPERO registration number

CRD42020221594.
Hybrid rail track quality analysis using nonlinear dimension reduction technique with machine learning
Authors: Lasisi Ahmed , Attoh-Okine Nii
Published: January 2021

Track geometry parameters from rail track inspection are regulated within unique safety limits for different track classes. This study focuses on developing an index that combines safety and track quality because of the inefficiency of corrective maintenance activities between routine maintenance cycles when federal geometry limits are violated. This combination is achievable by summarizing multivariate track geometry parameters as an improvement to previous linear approaches to address the problem of inefficient track geometry maintenance programs. The use of nonlinear dimension reduction (T-stochastic neighbor embedding (T-SNE)) for hybrid track quality index development and the influence of time-based parameters on track quality is evaluated in this study. The results show that the probability of geometry defects is correlated with principal components, but T-SNE had the best prediction on train-test splits despite its poor performance on a blind validation set. The absence of an observable correlation between the track geometry and acceleration data requires further investigation.
Morphological and genetic concordance of cutthroat trout (Oncorhynchus clarkii) diversification from western North America
Authors: Keeley Ernest R. , Loxterman Janet L. , Matsaw Sammy L. , Njoroge Zacharia M. , Seiler Meredith B. , Seiler Steven M.
Published: January 2021

The cutthroat trout (Oncorhynchus clarkii (Richardson, 1836)) is one of the most widely distributed species of freshwater fish in western North America. Occupying a diverse range of habitats, they exhibit significant phenotypic variability that is often recognized by intraspecific taxonomy. Recent molecular phylogenies have described phylogenetic diversification across cutthroat trout populations, but no study has provided a range-wide morphological comparison of taxonomic divisions. In this study, we used linear- and geometric-based morphometrics to determine if phylogenetic and subspecies divisions correspond to morphological variation in cutthroat trout, using replicate populations from throughout the geographic range of the species. Our data indicate significant morphological divergence of intraspecific categories in some, but not all, cutthroat trout subspecies. We also compare morphological distance measures with distance measures of mtDNA sequence divergence. DNA sequence divergence was positively correlated with morphological distance measures, indicating that morphologically more similar subspecies have lower sequence divergence in comparison to morphologically distant subspecies. Given these results, integrating both approaches to describing intraspecific variation may be necessary for developing a comprehensive conservation plan in wide-ranging species.
On the Commutative Equivalence of Algebraic Formal Series and Languages
Authors: Carpi Arturo , D’Alessandro Flavio
Published: January 2021

The problem of the commutative equivalence of context-free and regular languages is studied. Conditions ensuring that a context-free language of exponential growth is commutatively equivalent with a regular language are investigated.
Effects of Personalized and Aggregate Top-N Recommendation Lists on User Preference Ratings
Authors: Adomavicius Gediminas , Bockstedt Jesse , Curley Shawn , Zhang Jingjing
Published: January 2021

Prior research has shown a robust effect of personalized product recommendations on user preference judgments for items. Specifically, the display of system-predicted preference ratings as item recommendations has been shown in multiple studies to bias users’ preference ratings after item consumption in the direction of the predicted rating. Top-N lists represent another common approach for presenting item recommendations in recommender systems. Through three controlled laboratory experiments, we show that top-N lists do not induce a discernible bias in user preference judgments. This result is robust, holding for both lists of personalized item recommendations and lists of items that are top-rated based on averages of aggregate user ratings. Adding numerical ratings to the list items does generate a bias, consistent with earlier studies. Thus, in contexts where preference biases are of concern to an online retailer or platform, top-N lists, without numerical predicted ratings, would be a promising format for displaying item recommendations.
Multilingual Review-aware Deep Recommender System via Aspect-based Sentiment Analysis
Authors: Liu Peng , Zhang Lemei , Gulla Jon Atle
Published: January 2021

With the dramatic expansion of international markets, consumers write reviews in different languages, which poses a new challenge for Recommender Systems (RSs) dealing with this increasing amount of multilingual information. Recent studies that leverage deep-learning techniques for review-aware RSs have demonstrated their effectiveness in modelling fine-grained user-item interactions through the aspects of reviews. However, most of these models can neither take full advantage of the contextual information from multilingual reviews nor discriminate the inherent ambiguity of words originated from the user’s different tendency in writing. To this end, we propose a novel Multilingual Review-aware Deep Recommendation Model (MrRec) for rating prediction tasks. MrRec mainly consists of two parts: (1) Multilingual aspect-based sentiment analysis module (MABSA), which aims to jointly extract aligned aspects and their associated sentiments in different languages simultaneously with only requiring overall review ratings. (2) Multilingual recommendation module that learns aspect importances of both the user and item with considering different contributions of multiple languages and estimates aspect utility via a dual interactive attention mechanism integrated with aspect-specific sentiments from MABSA. Finally, overall ratings can be inferred by a prediction layer adopting the aspect utility value and aspect importance as inputs. Extensive experimental results on nine real-world datasets demonstrate the superior performance and interpretability of our model.
Evaluation of Diaphragms and Membranes as Separators for Alkaline Water Electrolysis
Authors: Brauns Jörn , Schönebeck Jonas , Kraglund Mikkel Rykær , Aili David , Hnát Jaromír , Žitka Jan , Mues Willem , Jensen Jens Oluf , Bouzek Karel , Turek Thomas
Published: January 2021

The separator is a critical component for the performance of alkaline water electrolysis as it ensures the ionic contact between the electrodes and prevents the product gases from mixing. While the ionic conductivity of the separator affects the cell voltage, the permeability of the dissolved product gases influences the product gas impurity. Currently, diaphragms are used as separators, the pore system of which is filled with the electrolyte solution to enable the exchange of ions. The breakthrough of the gas phase can be prevented up to a specific differential pressure. A drawback of diaphragms is the requirement of a highly concentrated electrolyte solution to maintain a high ionic conductivity. The usage of anion-exchange membranes could solve this problem. However, the long-term stability of such materials remains unproven. This study compares two pre-commercial diaphragms, an anion-exchange membrane, and an ion-solvating membrane with the state-of-the-art diaphragm ZirfonTM Perl UTP 500. Besides physical characterization, the material samples were evaluated electrochemically to determine the ohmic resistance and the product gas impurities. The results show that the thinner diaphragm outperforms the reference material and that polymer membranes can compete with the performance of the reference material.
Electroreduction of Perchlorinated Silanes for Si Electrodeposition
Authors: Downes Nathanael , Cheek Quintin , Maldonado Stephen
Published: January 2021

The electrochemical reactivity and suitability of hexachlorodisilane and tetrakis(trichlorosilyl)silane as Si ec-LLS electrodeposition precursors in several electrolyte solutions have been investigated. Voltammetric data indicated that perchlorinated silanes exhibit mechanistically similar electrochemical responses as SiCl4, regardless of the Si–Si bond content in the precursor. The voltammetric responses were a strong function of the concentration of the precursor, indicating the participation of electrogenerated intermediates during the reduction and concomitant Si electrodeposition. Variation of the anion in the supporting electrolyte was found to be a critical factor for the thermal and chemical stability of the precursor bath. A combination of chronoamperometry and electron microscopy data were used to study the deposition efficiency specifically for hexachlorodisilane. The faradaic efficiency was low, regardless of overpotential or the composition of the electrolyte. Cumulatively, these data show that while larger chlorosilanes can be used for conventional Si electrodeposition over a wider range of conditions, their chemical instability and propensity for low faradaic efficiency limit their utility as reagents relative to SiCl4 for Si electrodeposition by ec-LLS.
Communication—Synthesis of Highly-Branched Silver Nanocrystals for EMI Shielding Applications
Authors: Pai Ying-Hao , Hsu Mao-Feng , Chung Sheng-Feng , Huang Chi-Fei , Chu Yu-Cheng , Lin Hung-Chieh , Chen Chun-Hua
Published: January 2021

The innovative three-dimensional (3-D) nanocrystals constructed by 1-D stalactite-like branches with a diameter of 107 ± 27 nm and a varied length of a few hundred nanometers were successfully synthesized via a facile tri-block copolymer assisted chemical approach. The highly-branched Ag nanocrystals were applied as promising electrical conducting fillers to form PVP-based composites for electromagnetic interference (EMI) shielding applications. In comparison with the dense Ag-flakes based film, the slip-coated sponge-like Ag film exhibits a comparably-high electrical conductivity after annealing and a stably-excellent EMI shielding effectiveness of 47−53 dB over the frequency from 500 MHz to 10 GHz.
A Deep Eutectic Solvent as Leaching Agent and Electrolytic Bath for Silver Recovery from Spent Silver Oxide Batteries
Authors: Sánchez-Ortiz W. , Aldana-González J. , Le Manh Tu , Romero-Romo M. , Mejía-Caballero I. , Ramírez-Silva M. T. , Arce-Estrada E. M. , Mugica-Álvarez V. , Palomar-Pardavé M.
Published: January 2021

It is shown for the first time that the deep eutectic solvent, DES, formed by acetylcholine chloride and urea can be successfully used for Ag recovery from the cathode powder of spent silver oxide batteries. This DES performs two important functions namely, as selective leaching liquor to extract Ag(I) ions from the remaining Ag2O, leaving intact the metallic Ag in the solid phase, and as electrolytic bath for silver electrodeposition onto a glassy carbon electrode or graphite. Using potentiodynamic and potentiostatic electrochemical measurements, it was possible to quantify both: the Ag(I) leaching rate and the concentration of Ag(I) ions leached after 24 h. From this value, it was possible to estimate that about 7% of the original mass of the cathode powder corresponds to Ag2O and the rest to metallic Ag. Moreover, from potentiostatic current density transients, recorded during Ag electrodeposition, it was shown, for the first time in this DES, that this process occurs via multiple 3D nucleation with diffusion-controlled growth and valuable practical information i.e. the diffusion coefficient of Ag(I) ions in this media was quantified. From scanning electron microscopy images and energy-dispersive X-ray spectroscopy, the morphology and composition of the resulting deposits were characterized.
Hot and Cold Pressed LGPS Solid Electrolytes
Authors: Wang Yang , Hoang Binh , Hoerauf John , Lee Cholho , Lin Chuan-Fu , Rubloff Gary W. , Lee Sang Bok , Kozen Alexander C.
Published: January 2021

Li10GeP2S12 (LGPS) is a superionic conductor that has an ionic conductivity matching conventional liquid electrolytes (10−3 S cm−1) and thus shows exceptional potential to fulfill the promise of solid-state Li metal batteries. Conventional mechanical die pressing of LGPS powder into pellets for electrochemical testing can result in large porosity, low density, and large grain boundary resistance at the solid-solid interface with the electrodes which greatly decrease the performance of LGPS, in addition to poor mechanical stability of such pressed pellets. We demonstrate the use of hot pressing to fabricate of LGPS pellets using commercially available powder. We obtain pellets that are the most dense, and accordingly have the highest ionic conductance, at 150 °C. XPS demonstrates there is no chemical degradation of the LGPS powder during the hot pressing process.
Respirometric In Situ Methods for Real-Time Monitoring of Corrosion Rates: Part II. Immersion
Authors: Strebl M. G. , Bruns M. P. , Schulze G. , Virtanen S.
Published: January 2021

With the aim to open a new window into corrosion processes this paper presents respirometric methods for real-time in situ monitoring of corrosion rates under immersion conditions. With these techniques, sensitive, non-destructive corrosion rate measurements are possible on basically all metals and alloys. Different methods are presented that enable to monitor HER, ORR or both reactions simultaneously based on the amount of evolved H2 or the amount of consumed O2 by volumetric, manometric and sensor-based approaches. Various research examples are presented, demonstrating the benefits and limitations of the different approaches. For Mg alloys, besides HER, ORR plays a role in the cathodic reactions and a good correlation of the total cathodic charge with mass loss was obtained. H2 dissolution into the electrolyte was identified as an important factor. The results obtained for Zn immersion corrosion in intermittent-flow and flow-through respirometric experiments suggest that the ORR mechanism leads to the generation of stable H2O2 under these conditions. As a result, the effective number of exchanged electrons for one O2 molecule was found to be in between two and four. The here introduced respirometric techniques allow new insights into corrosion mechanisms, in addition to enabling real-time monitoring of corrosion.
Synthesis of ZSM-5 Zeolite from Metakaolin and Rice Husk Ash to CO2 Adsorption
Authors: Klunk Marcos Antonio , Das Mohuli , Dasgupta Sudipta , Caetano Nattan Roberto , Xavier Soyane Juceli Siqueira , de Souza Débora Machado , Wander Paulo Roberto , Moraes Carlos Alberto Mendes
Published: January 2021

Several mitigation processes involving carbon dioxide injection into adsorbent materials such as zeolites, are currently very popular as research studies. The objective of our present work is to apply the green synthesis method of molecular sieve with rice husk ash and metakaolin in four individual Si/Al ratios (20, 40, 60 and 80). The micrographs obtained with the aid of SEM (sample 80-ZSM-5) revealed a spherical morphology with aggregated particles. Analysis executed with EDS (Energy Dispersive Spectroscopy) confirmed the presence of Si, Al, O, K and Na. X-ray diffraction helped in the identification of crystalline phases related to the structures of zeolites mordenite and ZSM-5 (mostly). The zeolitic materials were tested for CO2 adsorption assays. The results demonstrated a considerable capacity of CO2 adsorption by 6.5 mmol g−1 of adsorbent at the pressure of 9 bar. Therefore, this research establishes zeolites of ZSM-5 type to be promising as adsorbents for CO2 capture.
Mechanical Characteristics and Mesostructural Damage of Saturated Limestone under Different Load and Unload Paths
Authors: Li Jielin , Hong Liu , Zhou Keping , Xia Caichu , Zhu Longyin
Published: January 2021

To study the evolutionary characteristics of mesostructural damage to saturated limestone under different loading and unloading paths, three types of loading and unloading tests involving three different loading rates and initial peak stresses were performed. Nuclear magnetic resonance technology and scanning electron microscopy were used to investigate the evolutionary characteristics of pore water during the loading and unloading of the limestone. The results indicated that, with an increase in the initial peak stress, the rock viscoplasticity gradually decreased, and the variation of pore radius and the reduction of bound water decreased. With an increasing loading rate, the mesostructure evolution law under disturbance‐increasing amplitude (DIA) cycling was opposite to those under increasing amplitude (IA) and repeated‐increasing amplitude (RIA) cycling. With the increasing loading stress level, the porosity decreased and then increased. Under increasing amplitude cycling, a larger initial porosity resulted in higher pore compaction and expansion limits. Reducing the initial peak stress inhibited the pore expansion, whereas it had the opposite effect under RIA and DIA cycling. During loading and unloading, bound water exists in pores of organic matter and mesopores, and free water exists in macropores of intergranular and transgranular fractures. These changes indicate certain laws under different loading and unloading paths. The results of this study indicate that the mesostructure characteristics of rock depend on the loading and unloading paths.
On the Performance of Self‐Concatenated Coding for Wireless Mobile Video Transmission Using DSTS‐SP‐Assisted Smart Antenna System
Authors: Minallah Nasru , Ahmed Ishtiaque , Ijaz Muhammad , Khan Atif Sardar , Hasan Laiq , Rehman Atiqur
Published: January 2021

In the current age of advanced technologies, there is an escalating demand for reliable wireless systems, catering to the high data rates of mobile multimedia applications. This article presents a novel approach to the concept of Self‐Concatenated Convolutional Coding (SECCC) with Sphere Packing (SP) modulation via Differential Space‐Time Spreading‐ (DSTS‐) based smart antennas. The two transmitters provide transmit diversity which is capable of recuperating the signal from the effects of fading, even with a single receiving antenna. The proposed DSTS‐SP SECCC scheme is probed for the Rayleigh fading channel. The SECCC structure is developed using the Recursive Systematic Convolutional (RSC) code with the aid of an interleaver. Interleaving generates randomness in exchange for extrinsic information between the constituent decoders. Iterative decoding is invoked at the receiving side to enhance the output performance by attaining fruitful convergence. The convergence behaviour of the proposed system is investigated using EXtrinsic Information Transfer (EXIT) curves. The performance of the proposed system is ascertained with the H.264 standard video codec. The perceived video quality of DSTS‐SP SECCC is found to be significantly better than that of the DSTS‐SP RSC. To be more precise, the proposed DSTS‐SP SECCC system exhibits an Eb/N0 gain of 8 dB at the PSNR degradation point of 1 dB, relative to the equivalent rate DSTS‐SP RSC. Similarly, an Eb/N0 gain of 10 dB exists for the DSTS‐SP SECCC system at 1 dB degradation point when compared with the SECCC scheme dispensing with the DSTS‐SP approach.
Geometrical Influences on the Vibration of Layered Plates
Authors: Javed Saira , Al Mukahal F. H. H. , El Sayed S. B. A.
Published: January 2021

This paper aims to study the influence of different geometric properties and support conditions on the vibration of layered plates of nonuniform thickness under shear deformation theory. The layered plates are supposed to have arbitrarily nonuniform thickness as linear, exponential, and sinusoidal. The spline approximation is used to approximate translational and angular displacement functions. Eigen frequency parameters are calculated by solving eigenvalue problem. The geometrical influences such as number of lay‐ups, different ply orientations, each ply consisting of different material, side‐to‐thickness ratio, and aspect ratio are taken into consideration to examine the frequency variation of plates for two different support conditions.
A Study on Efficacy of UGI Scopy in Cholelithiasis Patients before Laparoscopic Cholecystectomy
Authors: Kunnuru Supreeth Kumar Reddy , Kanmaniyan B. , Thiyagarajan Manuneethimaran , Singh Balaji K. , Navrathan Nitesh
Published: January 2021

Objectives. Upper abdominal symptoms are common in both gallstone disease and inflammatory disorders of gastroduodenum. To differentiate the causes of upper gastrointestinal symptoms due to gallstone and gastroduodenal disorders, upper gastrointestinal (UGI) scopy is a useful diagnostic tool. Our aim of study is to determine the efficacy of the preoperative UGI scopy and concurrent treatment of associated esophageal and gastric pathologies with symptomatic cholelithiasis in view of postoperative symptom reduction. Materials and Methods. This is a prospective study comprising 400 symptomatic cholelithiasis patients admitted in our institution. All patients underwent upper GI endoscopy (1–4 days) prior to cholecystectomy, and the findings were noted. Then, based on findings in UGI scopy, patients were grouped as group A (endoscopy normal) and group B (endoscopy with some findings). Group B patients were treated with medication, and both groups were operated with laparoscopic cholecystectomy. Pain and other symptoms in the preoperative period and postoperative period were measured and compared in both groups. Results. After excluding 7 patients with significant endoscopy findings, we have included 400 patients who underwent laparoscopy cholecystectomy. In a total of 400 patients, median age of presentation was 47.3 and female to male ratio was 2.2 : 1. Endoscopy showed some pathological findings in 75.5% patients, and the commonest endoscopy finding was gastritis. On comparison of pain score in preoperative patients, pain score was high in group B patients (

p
<
0.05

). Pain reduction was significant in postoperative 1st, 4th, and 6th weeks in both groups (

p
<
0.0005

). In the same way, other symptoms other than pain were compared which shows postoperative symptom reduction is highly significant in group B patients. Conclusion. Clinical presentation of cholelithiasis and other upper GI diseases resemble each other. It is difficult to discriminate between upper GI symptoms due to cholelithiasis or any other upper GI conditions. Although UGI scopy is not recommended for all patients with cholelithiasis, it may be beneficial to do UGI scopy in certain cholelithiasis patients with atypical presentation to prevent atypical symptoms after surgery.
Dynamic Response Analyses of Plastic Greenhouse Structure considering Fluctuating Wind Load
Authors: Jiang Yingchun , Bai Yikui , Wang Cong , Wang Yonggang , Pang Xinfu
Published: January 2021

Wind load is one of the main factors of plastic greenhouse collapse. To solve the dynamic response problem of greenhouses under wind load and determine the dangerous section of a skeleton structure, the investigated lump method is presented for the dynamic response analysis of a plastic greenhouse, considering pulsating wind on the basis of Timoshenko beam theory. First, the investigated lump is designed according to the Timoshenko beam microbody concept. On the basis of Timoshenko beam theory, the governing equations of the skeleton structure of the greenhouse are derived, and the realization process of the algorithm is also provided. Second, the accuracy and effectiveness of the proposed numerical method are verified by an example in which the bending wave of a variable cross section beam with free ends propagates. Finally, the dynamic response of the steel skeletons of plastic greenhouses is analyzed under the effect of the simulation wind speed, and the spatial distribution of the maximum node displacement and the section maximum stress of the steel skeleton are obtained. Computational results show that the displacement peak is near the top of the plastic greenhouse. The most dangerous section of the top chord in the steel skeleton is near the leeward bottom, which has a maximum stress of 219.4 MPa, and the most dangerous section of the bottom chord is near the 1 m height on the leeward side of the plastic greenhouse, which has a maximum stress of 248.5 MPa. Bending stress is the main factor of the rapid increase of stress at the bottom of the skeleton. The maximum node displacement and cross‐sectional stress caused by fluctuating wind loads are higher than those caused by average wind loads. The fluctuating wind load should be considered in the wind‐induced response analyses of plastic greenhouses.
Comparison of Two Different Bipolar Energy Resources in Transurethral Resection of Bladder Tumors
Authors: Kaynar Mehmet , Celik Zeliha Esin , Altintas Emre , Batur Ali Furkan , Kilic Ozcan , Akand Murat , Gul Murat , Goktas Serdar
Published: January 2021

Purpose: To determine whether the use of different bipolar resources is associated with different results on tissue and perioperative parameters in patients undergoing bipolar transurethral bladder tumor resection (bTURBT). Methods: In this single-center prospective study, patients diagnosed with bladder tumor randomized to undergo TURBT either with a Gyrus PlasmaKinetic system (n = 62) or Olympus TUR in saline (TURis) system (n = 51). Primary endpoint was to evaluate the alteration of patients’ perioperative parameters, while secondary aim was to assess the thermal effect of these 2 different bipolar devices on the resected tissue samples by a grading system determined by tissue characteristics. Results: One hundred thirteen patients were randomized in the study, and 43 were excluded from the analysis due to the exclusion criteria. There were no significant differences between the groups in terms of mean age, tumor site, number of tumors, operative time, alteration in hemoglobin or hematocrit, blood transfusion rate, catheterization time, and postoperative stay. On the other hand, the ratio of obturator jerk was significantly higher in the Olympus TURis group (p = 0.028). The histopathological analyses of both groups determined muscularis propria and cautery artifact presence without a statistically significant difference (χ2: 0.476, p = 0.788). Conclusion: Although the perioperative complications of bTURBT are low in nature, bladder perforation resulted from obturator jerk still poses a risk for extravesical tumor implantation. Urologists should be aware of this risk especially when they are using a TURis system.
Trabalho remoto na Educação Superior brasileira: efeitos e possibilidades no contexto da pandemia
Authors: Mancebo Deise
Published: January 2021

O texto problematiza o trabalho remoto a que milhões de trabalhadores brasileiros tiveram que aderir diante da necessidade do isolamento social imposto pela covid-19, tomando como campo empírico de análise a ampla utilização do ensino remoto na Educação Superior brasileira, tanto pública quanto privada. Para a apreensão da temática, ancora-se numa investigação de caráter exploratório, que contemplou pesquisa bibliográfica, levantamentos sistemáticos na imprensa alternativa e análise documental de problemáticas convergentes e necessárias à compreensão do tema, mas também na consulta de dados agregados já existentes, adotando, portanto, uma perspectiva que conjuga, a um só tempo, aspectos quantitativos e qualitativos.