bluuebunny/crossref_metadata_2025 huggingface dataset:
Survey attrition after 15 years of tracking children in four developing countries: The Young Lives study
Authors: Sánchez Alan , Escobal Javier
Published: March 2020

Young Lives (YL) is a multicountry, birth cohort study that, over a period of 15 years, followed nearly 8,000 individuals born in 2001–2002 and 4,000 individuals born in 1994–1995 in Ethiopia, India (states of Andhra Pradesh and Telangana), Peru, and Vietnam. This study aims to document attrition in the YL samples, to identify the correlates of attrition, and to test for attrition bias. The cumulative year‐to‐year attrition rate is 0.5% and 0.8% for the younger and older cohorts, respectively, among the lowest attrition rates in longitudinal studies in low‐ and middle‐income countries. Attrition rates vary by household wealth, area of residence, and ethnicity/caste across countries. Attrited individuals in Peru are poor and those in other countries are wealthier. When analyzing a set of nutritional and cognitive outcomes, suggestive evidence of attrition bias exists, part of which is driven by child mortality. Even though attrition is very low, our findings highlight the importance of controlling for household socioeconomic characteristics when performing statistical analysis of the YL samples. The study also highlights key insights that can be helpful to reduce attrition or ameliorate its effects in other longitudinal studies.
Labor market structure and offshoring
Authors: Shin Sangwha , Davidson Carl
Published: March 2020

We consider a two‐country, two‐sector model in which a firm’s offshoring decision depends on labor market rigidities that impose additional costs on the firm. Firms endogenously choose their organizational form considering their productivity level and organizational costs. The costs generated by labor market frictions play a key role in determining the benefits of each organizational structure, and thus helps determine the conditions under which a firm decides to offshore. There are three different types of equilibria depending on the relative levels of the domestic and foreign labor market costs and the price of the intermediate input. In all equilibria, a relative rise in the domestic labor market cost increases the share of firms that offshore, while decreasing domestic integration. Furthermore, an economy with offshoring has a higher welfare level and a lower unemployment rate than it would under autarky.
The role of echocardiography in prognosis for dysfunction and abandonment of radiocephalic arteriovenous fistula in elderly Chinese patients on hemodialysis
Authors: Xiong Yuqin , Yu Yang , Zhang Chunle , Morris Emily , Wang Liya , Deng Yuchen , Li Yi , Fu Ping
Published: March 2020

The objective of this study was to examine the impact of cardiac structure and function at baseline on the outcomes associated with arteriovenous fistula (AVF) in patients on hemodialysis (HD). Patients who initiated HD aged ≥70 years and received a mature AVF creation were included retrospectively. Echocardiographic parameters measured within 1 week before AVF creation were acquired. The observational period for each patient was from the point of AVF creation to the last time of follow‐up unless AVF abandonment or death occurred. Kaplan‐Meier and Cox proportional hazard regression analyses were conducted. A total of 82 elderly Chinese HD patients with mature radiocephalic AVF (RCAVF) and EF ≥50% were analyzed. During the median study period of 26.8 (12‐40) months, 42 (51.2%) experienced RCAVF dysfunction and 34 (41.5%) progressed to abandonment. Primary and cumulative patencies at 6, 12, 24, and 36 months were 81%, 73%, 48%, 38%, and 84%, 81%, 68%, 55%, respectively. Left ventricle end‐diastolic volume (LVEDV) ≤103.5 mL (HR = 2.5, P = .019) and the right side of RCAVF (HR = 3.59, P = .003) significantly predicted RCAVF dysfunction. The main pulmonary artery internal diameter (MPAID) ≤21.5 mm (HR = 4.3, P = .001) as well as the right side (HR = 2.95, P = .047) were the independent predictors for RCAVF abandonment. In conclusion, LVEDV, MPAID assessed by echocardiography and the right side of RCAVF, showed significant predictive implications for the outcomes of RCAVF. Disparities among nationalities in the areas of utilization and patency of AVFs necessitate additional studies.
A novel full‐length two‐domain KIR2DL5A allele isolated in Zimbabwean samples: KIR2DL5A*0010104
Authors: van Pul Lisa , Majonga Edith , Ferrand Rashida , Rowland‐Jones Sarah L. , Yindom Louis‐Marie
Published: March 2020

The novel allele KIR2DL5A*0010104 differs from that of KIR2DL5A*0010101 with eight single intronic nucleotide changes.
Simulated on‐call: time well spent
Authors: Misquita Lauren , Millar Lucy , Bartholomew Brent
Published: March 2020

Background

Newly qualified doctors feel unprepared to take responsibility for patients and work independently, lacking confidence in skills essential during on‐calls. We designed this study to assess the educational value of simulated on‐calls and to explore the characteristics of this approach that contribute to improving students’ preparedness.

Methods

A total of 38 final‐year medical students attended two sessions, each including a simulated on‐call followed by a one‐to‐one debriefing. Students’ confidence and perceived preparedness before and after the programme were measured using questionnaires. Students’ performance in two on‐call skills was also assessed during both sessions. Focus groups explored the challenges of preparing for on‐calls and how this approach enabled students to prepare.

Results

Following the programme, students felt significantly more confident in six key skills and significantly more prepared for on‐calls (p < 0.001). There was also a significant improvement in students’ assessed performance in on‐call skills (p < 0.001). All students found it more useful preparation for on‐calls than seminars and shadowing on‐call doctors. They appreciated the opportunity to work independently and take responsibility in a stressful but safe environment. Having a second session and receiving one‐to‐one debriefing with personalised feedback enabled students to maximise their learning.

Discussion

Following the programme, students had better insight into on‐call work and felt that the programme should be a mandatory part of training. The opportunity for students to consolidate learning through personalised feedback and a second session maximised the value of the programme, making the significant time commitment from the facilitators worthwhile.

Conclusions

This programme was feasible to run and its educational value supports its wider use.
Analysis of Different Uniflow Scavenging Options for a Medium-Duty 2-Stroke Engine for a U.S. Light-Truck Application
Authors: Turner J. W. G. , Head R. A. , Wijetunge R. , Chang J. , Engineer N. , Blundell D. W. , Burke P.
Published: March 2020

The work presented here seeks to compare different means of providing uniflow scavenging for a 2-stroke engine suitable to power a U.S. light-duty truck. Through the “end-to-end” nature of the uniflow scavenging process, it can in theory provide improved gas-exchange characteristics for such an engine operating cycle; furthermore, because the exhaust leaves at one end and the fresh charge enters at the other, the full circumference of the cylinder can be used for the ports for each flow, and therefore, for a given gas exchange angle-area demand, expansion can theoretically be maximized over more traditional loop-scavenging approaches. This gives a further thermodynamic advantage. The three different configurations studied, which could all utilize uniflow scavenging, were the opposed piston, the poppet-valve with piston-controlled intake ports, and the sleeve valve. These are described and all are compared in terms of indicated fuel consumption for the same cylinder swept volume, compression ratio, and exhaust pressure, for the same target indicated mean effective pressure (IMEP) and indicated specific power. A new methodology for optimization was developed using a one-dimensional engine simulation package which also took into account charging system work. The charging system was assumed to be a combination of supercharger and turbocharger to permit some waste energy recovery. As a result of this work, it was found that the opposed-piston configuration provides the best attributes since it allows maximum expansion and minimum heat transfer. Its advantage over the other two (whose results were very close) was of the order of 8.3% in terms of net specific fuel consumption (NSFC) (defined as indicted specific fuel consumption (ISFC) net of supercharger power). Part of its advantage also stems from its requirement for minimum air supply system work, included in this NSFC value. Interestingly, it was found that existing experiential guidelines for port angle-area specification for loop-scavenged, piston-ported engines using crankcase compression could also be applied to all of the other scavenging types. This has not been demonstrated before. The optimization process that was subsequently developed allowed port design to be tailored to specific targets, in this case lowest NSFC. The paper therefore presents a fundamental comparison of scavenging systems using a new approach, providing new insights and information which have not been shown before.
Modifying Stride Length in Isolation and in Combination With Foot Progression Angle and Step Width Can Improve Knee Kinetics Related to Osteoarthritis; A Preliminary Study in Healthy Subjects
Authors: Edd Shannon N. , Bennour Sami , Ulrich Baptiste , Jolles Brigitte M. , Favre Julien
Published: March 2020

The purpose of this study was to determine the effects of modifying stride length (SL) on knee adduction and flexion moments, two markers of knee loading associated with medial-compartment knee osteoarthritis (OA) progression. This study also tested if SL modifications, in addition to foot progression angle (FP) and step width (SW) modifications, provide solutions in more subjects for reducing knee adduction moment (KAM) without increasing knee flexion moment (KFM), potentially protecting the joint. Fourteen healthy subjects (six female) were enrolled in this preliminary study. Walking trials were collected first without instructions, and then following foot placement instructions for 50 combinations of SL, FP, and SW modifications. Repeated measures analysis of variance was used to detect group-average effects of footprint modifications on maximum KAM and KFM and on KAM impulse. Subject-specific dose–responses between footprint modifications and kinetics changes were modeled with linear regressions, and the models were used to identify modification solutions, per subject, for various kinetics change conditions. Shorter SL significantly decreased the three kinetics measures (p < 0.01). Potential solutions for 10% reductions in maximum KAM and KAM impulse without increasing maximum KFM were identified for five subjects with FP and SW modifications. A significantly higher proportion of subjects had solutions when adding SL modifications (11 subjects, p = 0.04). In conclusion, SL is a valuable parameter to modify, especially in combination with FP and SW modifications, to reduce markers of medial knee loading. Future work is needed to extend these findings to osteoarthritic knees.
Enhanced resistive switching characteristics of HfOx insulator fabricated by atomic layer deposition and La(NO3)3·6H2O solution as catalytic oxidant
Authors: Jung Yong Chan , Park In-Sung , Seong Sejong , Lee Taehoon , Kim Seon Yong , Ahn Jinho
Published: March 2020

Nanocrystalline HfOx films were synthesized by an atomic layer deposition method using Hf[N(CH3)C2H5]4 as the metal precursor and La(NO3)3·6H2O solution as the oxidant. La(NO3)3·6H2O solution played the role of both oxidant and catalyst, catalytic oxidant, where the La element in the deposited HfOx films was under the detection limit. The introduction of La(NO3)3·6H2O solution instead of H2O effectively altered the surface roughness, crystalline status, and resistive switching properties of HfOx films. Although the crystalline structures of both HfOx films made with La(NO3)3·6H2O solution and H2O were monoclinic, the surface roughness of the HfOx film grown by using the La(NO3)3·6H2O solution oxidant is smoother than that using H2O. Moreover, resistive switching characteristics of the HfOx insulator deposited with the La(NO3)3·6H2O solution oxidant enhanced not only uniformity of switching parameters but also endurance.
Campylobactercolitisleads to toxic megacolon and multiple organ failure
Authors: Clark Clair Louise Taylor , Murray Elspeth Victoria
Published: March 2020

A 58-year-old woman presented to the emergency department in a district general hospital with severe abdominal pain and diarrhoea, after collapsing at home. She was admitted to the intensive care unit (ICU) in septic shock, and with acute kidney injury. An initial CT scan was suggestive of colitis. She was treated for suspected gastroenteritis and her microbiology results showedCampylobacter colias the causative organism. She failed to respond to antibiotics, and underwent serial contrast CTs which showed no progression of colitis. Colonoscopy performed on day 10 of her admission, however, revealed fulminant colitis. After a multidisciplinary meeting among gastroenterologists, general surgeons and intensivists, the patient underwent total colectomy with ileostomy. She made a slow but steady recovery in ICU, and subsequently in the ward, and was discharged to a local community hospital for further rehabilitation.
Secondhand smoke from electronic cigarette resulting in hypersensitivity pneumonitis
Authors: Galiatsatos Panagis , Gomez Erin , Lin Cheng Ting , Illei Peter B , Shah Pali , Neptune Enid
Published: March 2020

Cases of vaping-induced lung injury have increased in the USA, resulting in a heterogeneous collection of pneumonitis patterns in persons who used electronic cigarettes. Hypersensitivity pneumonitis has been documented in several cases of first-hand electronic cigarette use; however, secondhand smoke health-related consequences have not been fully understood. We present a case of the patient who developed hypersensitivity pneumonitis secondary to exposure to secondhand smoke from electronic cigarette. We summarise the presentation and diagnostic investigation, as well as the management of this case.
Prevalence and risk factors of tinea pedis in Georgian Defense Forces
Authors: Kintsurashvili Nana , Kvlividze O , Galdava G
Published: March 2020

Introduction

Tinea pedis is a widely spread infection among military personnel. The aim of the research was to determine the prevalence of tinea pedis and its associated risk factors in Georgian Defense Forces.

Methods

A cross-sectional study including interviews and clinical and laboratory examination was performed among randomly selected Georgian soldiers and civilians, after getting the signed consent form from them. In the selected population with clinical evidence of tinea pedis, scrapings were taken for direct microscopic examination. Statistical Package for Social Sciences V.22.0 was used for ststistical analysis.

Results

Out of 729 soldiers, tinea pedis was clinically observed in 46.64% (n=340) and laboratory-confirmed in 25.24% (n=184) of cases, while out of 279 civilians, tinea pedis was found in 21.86% (n=61) and approved in 13.98%(n=39). Multivariate analysis demonstrated that tinea pedis is correlated with the age and military ranks but is not associated with the length of military service. Using a communal shower (OR=1.04, 95% CI 1.01 to 1.07) and having tinea pedis before military service (OR=3.27, 95% CI 1.79 to 5.96) increase the chances of tinea pedis development, though using two or more pairs of the military boots interchangeably decreases the spread of disease (OR=0.21, 95% CI 0.15 to 0.29).

Conclusions

According to our research analysis, the prevalence of tinea pedis among Georgian militaries is significantly higher than that in the civilians. It is necessary to develop a large-scale strategy and to implement appropriate preventive measures to minimise the discomfort caused by this disease.
Complications and outcomes of urgent-start peritoneal dialysis in elderly patients with end-stage renal disease in China: a retrospective cohort study
Authors: Zang Xiujuan , Du Xiu , Li Lin , Mei Changlin
Published: March 2020

Objectives

To investigate the complications and survival of elderly patients with end-stage renal disease (ESRD) who received urgent-start peritoneal dialysis (USPD) or urgent-start haemodialysis (USHD), and to explore the value of peritoneal dialysis (PD) as the emergent dialysis method for elderly patients with ESRD.

Design

Retrospective cohort study.

Setting

Two tertiary care hospitals in Shanghai, China.

Participants

Chinese patients (n=542) >65 years of age with estimated glomerular filtration rate ≤15 mL/min/m2who received urgent-start dialysis between 1 January 2005 and 31 December 2015, and with at least 3 months of treatment. Patients who converted to other dialysis methods, regardless of the initial dialysis method, were excluded, as well as those with comorbidities that could significantly affect their dialysis outcomes.

Primary and secondary outcome measures

Dialysis-related complications and survival were compared. Patients were followed until death, stopped PD, transfer to other dialysis centres, loss to follow-up or 31 December 2016.

Results

There were 309 patients in the USPD group and 233 in the USHD group. The rate of dialysis-related complications within 30 days after catheter implantation was significantly lower in the USPD group compared with the USHD group (4.5% vs 10.7%, p=0.031). The 6-month and 1, 2 and 3-year survival rates were 95.3%, 91.4%, 86.6% and 64.8% in the USPD group, and 92.2%, 85.7%, 70.2% and 57.8% in the USHD group, respectively (p=0.023). The multivariable Cox regression analysis showed that USHD (HR=2.220, 95% CI 1.298 to 3.790; p=0.004), age (HR=1.025, 95% CI 1.013 to 1.043, p<0.001) and hypokalaemia (HR=0.678, 95% CI 0.487 to 0.970; p=0.032) were independently associated with death.

Conclusions

USPD was associated with slightly better survival compared with USHD. USPD was associated with fewer complications and better survival than USHD in elderly patients with ESRD.
Lubricant Investigation in Men to Inhibit Transmission of HPV Infection (LIMIT-HPV): design and methods for a randomised controlled trial
Authors: Laurie Cassandra , El-Zein Mariam , Tota Joseph , Tellier Pierre-Paul , Coutlée Francois , Franco Eduardo L , de Pokomandy Alexandra
Published: March 2020

Introduction

Gay, bisexual and other men who have sex with men (gbMSM) have an increased risk of human papillomavirus (HPV) infection and HPV-associated diseases, such as anal cancer and anogenital warts. A carrageenan-based lubricant could prevent HPV infection, thereby reducing the disease burden in this population. This paper describes the protocol for the Lubricant Investigation in Men to Inhibit Transmission of HPV Infection (LIMIT-HPV) study, an ongoing randomised controlled trial (RCT), evaluating efficacy of a carrageenan-based personal lubricant in reducing type-specific anal HPV incidence and prevalence among sexually active gbMSM, efficacy by HIV status, safety and tolerability of the gel and participant adherence to the intervention.

Methods and analysis

The study is a double-blinded, placebo-controlled RCT. Volunteer gbMSM 18 years and older are randomly assigned 1:1 to receive the treatment (a self-applied anal microbicide gel with carrageenan) or placebo (a self-applied placebo gel). At each visit, computerised questionnaires are used to collect data on sociodemographic and clinical variables, lifestyle, sexual behaviour and the gels’ safety and tolerability. At baseline and each follow-up visit (months 1, 2, 3, 6, 9 and 12), nurses collect anal specimens tested for 36 HPV types (linear array assay). HIV status is determined at baseline and 12 months. The primary outcome is incidence of type-specific anal HPV infection(s) undetected at baseline. Secondary outcomes are prevalence of type-specific anal HPV infection, safety, tolerability and adherence. We aim to recruit 380 participants to attain the study’s objectives. Data will be analysed using intention-to-treat and per-protocol approaches with subgroup analyses by HIV status.

Ethics and dissemination

Ethics approval was obtained by the Research Ethics Boards of McGill University, the McGill University Health Centre, Concordia University and Centre Hospitalier de l’Université de Montréal. Trial results will be disseminated through peer-reviewed publications and conference presentations.

Trial registration number

NCT02354144.
Systematic review of qualitative studies on participants in the decision-making process about the location of care of the elderly
Authors: Serrano-Gemes Gema , Rich-Ruiz Manuel , Serrano-del-Rosal Rafael
Published: March 2020

Objectives

To understand who are the participants in the decision-making process about the location of care of the elderly.

Design

Systematic review of qualitative studies.

Data sources

The following databases were consulted: Web of Science, MEDLINE, Scopus, CINAHL, PsycINFO and SciELO (from the beginning until 29 November 2017). The bibliographical references in the studies that were finally included in the review were also searched.

Study selection

The studies had to deal with the decision-making process (already experienced by the participants) on the location of care of the elderly (adults who are 65 or older), had to use a qualitative methodology and had to be written in English or Spanish.

Data extraction and synthesis

A data extraction tool was used. Data analysis was conducted through the constant comparative method from Glaser and Strauss’ grounded theory.

Results

46 studies were included in this review. Most of them were carried out in the USA, and in 21 of them the study population focused exclusively on the elderly. This review has found that there are many participants, with different roles and degrees of involvement, who may act jointly, separately or sequentially. These participants may be: the elders, family members, professionals and other relevant.

Conclusions

The main result of this review has been the variability found on how this decision is made, even varying the way of acting/perceiving the situation of the involved persons on certain occasions, simply due to the influence of some of the other groups of participants studied. Besides, this review has focused its results on the main participant in this process, the elders and how their family members interact with them when it comes to making this decision. This has allowed relevant results to be obtained about roles and degrees of involvement.

PROSPERO registration number

CRD42018084826.
Dyadic wavelet analysis of bender element signals in determining shear wave velocity
Authors: Chen Guan , Wang Fang-Tong , Li Dian-Qing , Liu Yong
Published: March 2020

Determining shear wave velocity is a critical technique in bender element tests, as it can be readily affected by near-field effects, wave reflection, and other factors. This study proposes a new method based on the dyadic wavelet transform modulus maxima. Combining the local modulus maxima of dyadic wavelet transform approximate coefficients at fine decomposition levels and an appropriate threshold value, the proposed method can automatically detect the target point. For validation, a comparative study among the dyadic wavelet transform modulus maxima, peak-to-peak, first arrival, and cross-correlation methods was carried out using 140 sets of bender element signals. The comparison results show that the proposed method not only mitigates the adverse effects of near-field, later major peaks, and noise contamination, but is also more robust in estimating shear wave velocity.
Usability Requirements Extraction Method from Software Document
Authors: Hassan Rohayanti , Fauzi Noor Atikah Amira , Kasim Shahreen , Omer Herman Khalid
Published: March 2020

Extracting the usability requirements are crucial during requirements review and requirements validation for different purposes. Usability requirements are hard to be determined until the real user has experienced the software. It is even more challenging when these usability requirements are documented in natural language, which has an inconsistent and unrestricted structure. Automated requirements extraction has been widely studied to facilitate the process of requirements checking. Nevertheless, the accuracy of requirements extraction method still can be improved. Thus, this paper has presented the usability keywords repository that followed the ISO 9126 and ISO 25010 usability category and has gone through the expert validation process. The usability requirement extraction method is moreover enhanced with extra procedures in conforming the usability requirement statement. First, each statement in the requirement document is checked if there is a keyword usability, whereby the keywords used must match with the usability keyword repository. In order to ensure that the selected statement is a usability requirement, the corresponding usability keyword position should be after the fixed auxiliary verbs. The performance of the improved usability requirements extraction method is then evaluated using precision, recall and accuracy.
Log-Based Anomaly Detection with the Improved K-Nearest Neighbor
Authors: Wang Bingming , Ying Shi , Cheng Guoli , Wang Rui , Yang Zhe , Dong Bo
Published: March 2020

Logs play an important role in the maintenance of large-scale systems. The number of logs which indicate normal (normal logs) differs greatly from the number of logs that indicate anomalies (abnormal logs), and the two types of logs have certain differences. To automatically obtain faults by K-Nearest Neighbor (KNN) algorithm, an outlier detection method with high accuracy, is an effective way to detect anomalies from logs. However, logs have the characteristics of large scale and very uneven samples, which will affect the results of KNN algorithm on log-based anomaly detection. Thus, we propose an improved KNN algorithm-based method which uses the existing mean-shift clustering algorithm to efficiently select the training set from massive logs. Then we assign different weights to samples with different distances, which reduces the negative effect of unbalanced distribution of the log samples on the accuracy of KNN algorithm. By comparing experiments on log sets from five supercomputers, the results show that the method we proposed can be effectively applied to log-based anomaly detection, and the accuracy, recall rate and F measure with our method are higher than those of traditional keyword search method.
A survey on the current internet interconnection practices
Authors: Marcos Pedro , Chiesa Marco , Dietzel Christoph , Canini Marco , Barcellos Marinho
Published: March 2020

The Internet topology has significantly changed in the past years. Today, it is richly connected and flattened. Such a change has been driven mostly by the fast growth of peering infrastructures and the expansion of Content Delivery Networks as alternatives to reduce interconnection costs and improve traffic delivery performance. While the topology evolution is perceptible, it is unclear whether or not the interconnection process has evolved or if it continues to be an ad-hoc and lengthy process. To shed light on the current practices of the Internet interconnection ecosystem and how these could impact the Internet, we surveyed more than 100 network operators and peering coordinators. We divide our results into two parts: (
i
) the current interconnection practices, including the steps of the process and the reasons to establish new interconnection agreements or to renegotiate existing ones, and the parameters discussed by network operators. In part (
ii
), we report the existing limitations and how the interconnection ecosystem can evolve in the future. We show that despite the changes in the topology, interconnecting continues to be a cumbersome process that usually takes days, weeks, or even months to complete, which is in stark contrast with the desire of most operators in reducing the interconnection setup time. We also identify that even being primary candidates to evolve the interconnection process, emerging on-demand connectivity companies are only fulfilling part of the existing gap between the current interconnection practices and the network operators' desires.
Perspective—Electrochemical Stability of Water-in-Salt Electrolytes
Authors: Kühnel Ruben-Simon , Reber David , Battaglia Corsin
Published: March 2020

The water-in-salt approach has expanded the electrochemical stability window of aqueous electrolytes, enabling novel aqueous batteries with relatively high cell voltages and energy densities. However, the stability of these electrolytes tends to be overestimated. The instability of the electrolyte is typically masked by high rates and a large excess amount of electrolyte present in lab cells. Based on a discussion of practical cells, we revisit voltammetry data and offer guidelines for a more stringent evaluation of electrochemical stability window data.
Effects of the Transport/Catalyst Layer Interface and Catalyst Loading on Mass and Charge Transport Phenomena in Polymer Electrolyte Membrane Water Electrolysis Devices
Authors: Lopata J. , Kang Z. , Young J. , Bender G. , Weidner J. W. , Shimpalee S.
Published: March 2020

The properties of porous transport layers (PTL) in electrolysis devices and their effects on cell performance have been studied extensively in recent literature. This paper provides a detailed analysis with regards to the transport in the catalyst layer (CL). The work demonstrated that the catalyst loading affects the sensitivity of electrolysis performance to PTL properties, particularly those of the PTL surface in contact with the CL. It was demonstrated that upon reducing catalyst loading, PTL properties had an increased effect on the performance of PEMWE cells. While we observed mild performance variations among PTLs when using a high anode catalyst loading, strong correlations between PTL surface properties and cell performance existed at a low catalyst loading. PTL properties affected performance by influencing the in-plane conductivity and permeability of the CL. The variation of apparent exchange current density and apparent CL bubble coverage with the stoichiometric flow rate was studied at low anode feed rates. This led to the emergence of a PTL grain size effect on apparent bubble coverage at high catalyst loading. We provide a descriptive analysis of the phenomena causing voltage losses in PEMWE devices. These findings are important for electrochemical modeling and designing the PTL/CL interface.
Pt/Ru–Sn Oxide/Carbon Catalysts for Ethanol Oxidation
Authors: Hang Hui , Altarawneh Rakan M. , Brueckner Tobias M. , Pickup Peter G.
Published: March 2020

Mixed Ru–Sn oxides have been deposited onto a high surface area carbon support by thermal decomposition of Ru and Sn acetylacetonate (acac) complexes. Adsorption of preformed Pt nanoparticles produced catalysts with enhanced low potential activity for the oxidation of ethanol in aqueous sulfuric acid at ambient temperature and in a proton exchange membrane (PEM) cell at 80 °C. Varying the oxide composition between Ru0.38Sn0.62O2 and Ru0.67Sn0.33O2 did not influence the catalyst’s activity greatly but did increase stability in the sulfuric acid solution. Higher stability was observed in the PEM cell, where a Pt/Ru0.55Sn0.45O2/C anode provided much higher currents than a commercial Pt/C catalyst for ethanol oxidation at low potentials. Anodes for direct ethanol fuel cells can be fabricated by coating a carbon fibre paper backing layer consecutively with carbon black, Ru(acac)3 + Sn(acac)2, and Pt nanoparticles, with appropriate thermal processing.
Interface Modification of lithium Metal Anode and Solid-state Electrolyte with Gel Electrolyte
Authors: Renna Lawrence A. , Blanc Francois-Guillame , Giordani Vincent
Published: March 2020

The interface between solid electrolytes and Li metal anode is a significant hurdle for the development of all-solid-state lithium metal batteries. Introducing a thin gel polymer electrolyte interlayer to conformally coat solid electrolytes can improve the interface wettability of Li metal anode and thus reduce the interfacial resistance. Here we used a plasticized poly(ethylene oxide)-based electrolyte with high concentrations of bis(trifluoromethane)sulfonamide lithium (LiTFSI) that show 100% amorphous character. These electrolytes show Li+ conductivity as high as σ = 2.9 × 10−4 S cm−1 at room temperature. We discovered by thermogravimetric analysis (TGA) with off-gas analysis in conjunction with nuclear magnetic resonance (NMR) spectroscopy that the electrolyte films had absorbed N-methyl-2-pyrrolidone (NMP) vapors to form a gel electrolyte. We incorporated the gel electrolyte as an interfacial modification layer between LLZO and Li metal electrodes and found a 58 times reduction in the area specific resistance (ASR) at room temperature.
Distinct functions of megalin and cubilin receptors in recovery of normal and nephrotic levels of filtered albumin
Authors: Ren Qidong , Weyer Kathrin , Rbaibi Youssef , Long Kimberly R. , Tan Roderick J. , Nielsen Rikke , Christensen Erik I. , Baty Catherine J. , Kashlan Ossama B. , Weisz Ora A.
Published: March 2020

Proximal tubule (PT) cells express a single saturable albumin-binding site whose affinity matches the estimated tubular concentration of albumin; however, albumin uptake capacity is greatly increased under nephrotic conditions. Deciphering the individual contributions of megalin and cubilin to the uptake of normal and nephrotic levels of albumin is impossible in vivo, as knockout of megalin in mice globally disrupts PT endocytic uptake. We quantified concentration-dependent albumin uptake in an optimized opossum kidney cell culture model and fit the kinetic profiles to identify albumin-binding affinities and uptake capacities. Mathematical deconvolution fit best to a three-component model that included saturable high- and low-affinity uptake sites for albumin and underlying nonsaturable uptake consistent with passive uptake of albumin in the fluid phase. Knockdown of cubilin or its chaperone amnionless selectively reduced the binding capacity of the high-affinity site, whereas knockdown of megalin impacted the low-affinity site. Knockdown of disabled-2 decreased the capacities of both binding sites. Additionally, knockdown of megalin or disabled-2 profoundly inhibited the uptake of a fluid phase marker, with cubilin knockdown having a more modest effect. We propose a novel model for albumin retrieval along the PT in which cubilin and megalin receptors have different functions in recovering filtered albumin in proximal tubule cells. Cubilin binding to albumin is tuned to capture normally filtered levels of the protein. In contrast, megalin binding to albumin is of lower affinity, and its expression is also essential for enabling the recovery of high concentrations of albumin in the fluid phase.
A Short-Term Load Forecasting Method Based on GRU-CNN Hybrid Neural Network Model
Authors: Wu Lizhen , Kong Chun , Hao Xiaohong , Chen Wei
Published: March 2020

Short-term load forecasting (STLF) plays a very important role in improving the economy and stability of the power system operation. With the smart meters and smart sensors widely deployed in the power system, a large amount of data was generated but not fully utilized, these data are complex and diverse, and most of the STLF methods cannot well handle such a huge, complex, and diverse data. For better accuracy of STLF, a GRU-CNN hybrid neural network model which combines the gated recurrent unit (GRU) and convolutional neural networks (CNN) was proposed; the feature vector of time sequence data is extracted by the GRU module, and the feature vector of other high-dimensional data is extracted by the CNN module. The proposed model was tested in a real-world experiment, and the mean absolute percentage error (MAPE) and the root mean square error (RMSE) of the GRU-CNN model are the lowest among BPNN, GRU, and CNN forecasting methods; the proposed GRU-CNN model can more fully use data and achieve more accurate short-term load forecasting.
SiameseDenseU-Net-based Semantic Segmentation of Urban Remote Sensing Images
Authors: Dong Rongsheng , Bai Lulu , Li Fengying
Published: March 2020

Boundary pixel blur and category imbalance are common problems that occur during semantic segmentation of urban remote sensing images. Inspired by DenseU-Net, this paper proposes a new end-to-end network—SiameseDenseU-Net. First, the network simultaneously uses both true orthophoto (TOP) images and their corresponding normalized digital surface model (nDSM) as the input of the network structure. The deep image features are extracted in parallel by downsampling blocks. Information such as shallow textures and high-level abstract semantic features are fused throughout the connected channels. The features extracted by the two parallel processing chains are then fused. Finally, a softmax layer is used to perform prediction to generate dense label maps. Experiments on the Vaihingen dataset show that SiameseDenseU-Net improves the F1-score by 8.2% and 7.63% compared with the Hourglass-ShapeNetwork (HSN) model and with the U-Net model. Regarding the boundary pixels, when using the same focus loss function based on median frequency balance weighting, compared with the original DenseU-Net, the small-target “car” category F1-score of SiameseDenseU-Net improved by 0.92%. The overall accuracy and the average F1-score also improved to varying degrees. The proposed SiameseDenseU-Net is better at identifying small-target categories and boundary pixels, and it is numerically and visually superior to the contrast model.
Screening Level of Gross Alpha and Beta Activities in Building Materials
Authors: Jemii Elassaad
Published: March 2020

The objective of the present study is the screening of the gross alpha and gross beta activity of some building materials commercialized in Saudi Arabia. The measurements were carried out using a gas flow proportional counter. The study has shown that the gross alpha activity ranged between 0.21 and 8.27 Bq/kg with an average activity of about 1.96 Bq/kg, whereas the gross beta activity ranged between 6.47 and 276.47 Bq/kg with an average activity of about 65.27 Bq/kg. The obtained values of gross alpha and beta activities are in the worldwide range and no significant activity was observed that accentuate the attention, which show that no radiation risks come from these building materials and, therefore, from their origin areas.
Systemic Factors Associated with Treatment Response in Diabetic Macular Edema
Authors: Wong Wendy Meihua , Chee Caroline , Bhargava Mayuri , Chai Charmaine , Lin Hazel , Zhao Paul , Ariadarma Mangunkusumo Erlangga , Naing Thet , Yuen Yew Sen , Wong Tien Yin , Su Xinyi , Lingam Gopal
Published: March 2020

Purpose. To identify systemic factors that may influence the response to anti-VEGF therapy in patients with diabetic macular edema (DME). Methods. 35 patients undergoing anti-VEGF injections for centre-involving DME were studied in this prospective observational study. The primary outcome was change in macular thickness one month after treatment, measured using spectral-domain optical coherence tomography (OCT). At baseline, information on various systemic factors was collected including glycosylated hemoglobin (HbA1c), serum VEGF levels, lipid profile and markers of renal function, and blood pressure. Thirty-three of the 35 patients were included in this study. Nonparametric statistical tests were used for the analysis of the data in view of the nonnormal distribution of the outcome variables. Multivariate analysis was performed using logistic regression. Stata 12.1 software was used for the analysis. Main Outcome Measures. Reduction in macular central subfield thickness (on spectral-domain OCT) and change in logMAR visual acuity at one month after injection. Results. Lower HbA1c levels (7% or less) were significantly associated with greater reduction in central macular subfield thickness at one month after injection of bevacizumab or ranibizumab on both univariate analysis (p=0.012) and multivariate analysis (p=0.042). Conclusions. Better glycemic control is associated with a greater reduction in central macular thickness after the first injection of bevacizumab or ranibizumab in diabetic macular edema. Patients with high levels of HbA1c and poor response to anti-VEGF may benefit from strict control of their blood glucose.
Sociodemographic and Lifestyle Factors Associated with Adherence to Mediterranean Diet in Representative Adult Population in Casablanca City, Morocco: A Cross-Sectional Study
Authors: Mohtadi Karima , Msaad Rajaa , Benalioua Najwa , Jafri Ali , Meftah Hasnaa , Elkardi Younes , Lebrazi Halima , Kettani Anass , Derouiche Abdelfettah , Taki Hassan , Saïle Rachid
Published: March 2020

Several studies had revealed that following the Mediterranean diet (MD) contributes to beneficial health status and a decreased risk of many chronic diseases. The aim of our study was to assess adherence to MD in Casablanca City and to identify the relationship between MD adherence and sociodemographic and lifestyle parameters. This cross-sectional study concerned 719 subjects with complete dietary data. Data collection was performed using a questionnaire including sociodemographic and lifestyle factors. The dietary intake was assessed with the use of a food-frequency questionnaire. The compliance with MD was evaluated with a simplified MD score. Our study showed that high adherence to the MD was characterized by high intakes of vegetables, fruits, pulses, fish, cereals, olive oil, and low meat and dairy consumption according to the Simplified MD score. As regard to the multivariate logistic, being a man, being married, persons with a level of education >6 years, luxurious housing, and consumption of alcohol were associated with a higher adherence to MD, while, the overweight was negatively associated with a higher adherence to MD. Maintaining the traditional MD pattern is crucial for public health; in this way, more research is needed in this area in order to precisely measure these associations.
Forecasting Natural Gas Consumption of China Using a Novel Grey Model
Authors: Zheng Chengli , Wu Wen-Ze , Jiang Jianming , Li Qi
Published: March 2020

As is known, natural gas consumption has been acted as an extremely important role in energy market of China, and this paper is to present a novel grey model which is based on the optimized nonhomogeneous grey model (ONGM (1,1)) in order to accurately predict natural gas consumption. This study begins with proving that prediction results are independent of the first entry of original series using the product theory of determinant; on this basis, it is a reliable approach by inserting an arbitrary number in front of the first entry of original series to extract messages, which has been proved that it is an appreciable approach to increase prediction accuracy of the traditional grey model in the earlier literature. An empirical example often appeared in testing for prediction accuracy of the grey model is utilized to demonstrate the effectiveness of the proposed model; the numerical results indicate that the proposed model has a better prediction performance than other commonly used grey models. Finally, the proposed model is applied to predict China’s natural gas consumption from 2019 to 2023 in order to provide some valuable information for energy sectors and related enterprises.
A Modified Surgical Technique of Fovea-Sparing Internal Limiting Membrane Peeling: Continuous Arc-Shaped Foldback Peeling
Authors: Xie Zheng-Gao , He Qing-Yi , Zhu Jun , Du Wei , Tong Jun , Chen Fang
Published: March 2020

Purpose. To investigate the efficacy of management of high myopic foveoschisis (MF) with a modified surgical technique of arc-shaped foldback fovea-sparing internal limiting membrane (ILM) peeling. Methods. A 23-gauge vitrectomy was performed in five patients with high MF. A long strip of ILM was peeled at the temporal side of the central fovea. Next, an ILM forceps was used to grasp the outer side of the ILM flap, and it was moved forward slowly from the outside to the paracentral fovea, followed by folding ILM back in an arc-shaped manner and then removing it. The above operations were repeated, and all ILM flaps were removed from the outside to paracentral fovea until a narrow strip of ILM remained. Finally, the narrow strip of ILM was excised using a vitreous cutter. Results. At the patients’ last visits, the foveoschisis almost disappeared completely and the fovea reattached. The central macular thickness statistically decreased from 399.0 ± 96.33 μm preoperatively to 164.60 ± 34.20 μm postoperatively (t = 4.289; P=0.013). The preoperative mean logarithm of the minimum angle of resolution best-corrected visual acuity (1.64 ± 0.65) significantly improved to 0.72 ± 0.18 postoperatively (t = 3.265, P=0.031). The average follow-up time was 11.80 ± 3.35 months (range; 8–16 months). Conclusion. The arc-shaped foldback fovea-sparing ILM peeling technique for high MF is safe and effective.
Goitre Prevalence and Urinary Iodine Concentration in School-Aged Children in the Ashanti Region of Ghana
Authors: Gyamfi Daniel , Wiafe Yaw Amo , Ofori Awuah Enoch , Adu Evans Asamoah , Boadi Emmanuel Kodie
Published: March 2020

Background. Iodine deficiency is a public health problem. The universal salt iodization (USI) program is the main, simple, and cost-effective intervention strategy to control iodine deficiency. The study examined the iodine status in school-aged children in Ashanti region, Ghana, using thyroid volumes along with urinary iodine concentrations, the methods recommended by the WHO/ICCIDD for monitoring the sustained impact of USI programs. Methods. This cross-sectional study was conducted among school-aged children (6–12 years) from randomly selected schools in the central and northern part of the Ashanti region, Kumasi Metropolis, and Ejura-Sekyedumase Municipality, respectively. A total of 852 children were enrolled in the study. Thyroid volume and urinary iodine concentrations of the children were determined using the standardized methods recommended by WHO/ICCIDD. Anthropometric measurements were also evaluated. Results. The mean values of thyroid volume in female and male school-aged children were 3.53 ± 0.09 and 3.32 ± 0.07, respectively. The thyroid size was significantly associated with age (P<0.0001), weight (P<0.0001), height (P<0.0001), BMI (P<0.05), and BSA (P<0.0001) by Pearson’s correlation in both males and females. The P50 (median) thyroid volumes of school children investigated in this study were generally larger compared to the WHO/ICCIDD reference data by age and body surface area. The median value of urinary iodine concentration was 201.85 μg/L, which showed significant sex difference (P value <0.0001). Excessive iodine nutrition (≥300 μg/L) was observed among 34.4% of male children and 27.6% of female children. Also, 12.8% of the male and 19.5% of the female children had UIC below requirement (<100 μg/L). The criteria of thyroid volume per age yielded a goitre prevalence of 2.2%. In contrast, the criteria of thyroid volume by body surface area yielded a goitre prevalence of 0.9%. Conclusion. The study clearly indicated that adequate iodine nutrition exists generally among the school children. However, insufficient and excessive iodine intakes still persist among some of the children. The establishment of local reference values for thyroid volume that might be applicable to precisely define goitre prevalence in the Ghanaian context is highly recommended.