bluuebunny/crossref_metadata_2025 huggingface dataset:
Nanomechanical Subsurface Characterisation of Cellulosic Fibres
Authors: Auernhammer Julia , Langhans Markus , Schäfer Jan-Lukas , Keil Tom , Meckel Tobias , Biesalski Markus , Stark Robert W.
Published: May 2021

The mechanical properties of single fibres are highly important in the paper production process to produce and adjust properties for the favoured fields of application. The description of mechanical properties is usually characterised via linearized assumptions and is not resolved locally or spatially in three dimensions. In tensile tests or nanoindentation experiments on cellulosic fibres, only one mechanical parameter, such as elastic modulus or hardness, is usually obtained. To obtain a more detailed mechanical picture of the fibre, it is crucial to determine mechanical properties in depth. To this end, we discuss an atomic force microscopy-based approach to examine the local stiffness as a function of indentation depth via static force-distance curves. This method has been applied to linter fibres (extracted from a finished paper sheet) as well as to natural raw cotton fibres to better understand the influence of the pulp treatment process in paper production on the mechanical properties. Both types of fibres were characterised in dry and wet conditions with respect to alterations in their mechanical properties. Subsurface imaging revealed which wall in the fibre structure protects the fibre against mechanical loading. Via a combined 3D display, a spatially resolved mechanical map of the fibre interior near the surface can be established. Additionally, we labelled fibres with carbohydrate binding modules tagged with fluorescent proteins to compare the AFM results with fluorescence confocal laser scanning microscopy imaging. Nanomechanical subsurface imaging is thus a tool to better understand the mechanical behaviour of cellulosic fibres, which have a complex, hierarchical structure.
Measurement of Epicardial Fat Using Non-contrast Routine Chest-CT: A Consideration of Threshold Adjusting for Fatty Attenuation
Authors: Yin Lekang , Yan Cheng , Yang Chun , Dong Hao , Xu Shijie , Li Chenwei , Zeng Mengsu
Published: May 2021

Background：Role of epicardial fat (EF) had expended from a marker of cardiovascular risk to indicators of several systemic physiological effects and needed to be measured in more scenarios. The present study aimed to determine whether the EF volume (EFV) and mean attenuation (EFA) measured on non-contrast routine chest-CT (RCCT) could be more consistent with that on coronary CT angiography (CCTA) by adjusting the threshold of fatty attenuation. Methods: Totally 83 subjects simultaneously underwent CCTA and RCCT were enrolled. EFV and EFA were quantified on CCTA using threshold of (N30) (-190HU, -30HU) as reference, and also measured on RCCT using threshold of N30, N40 (-190HU, -40HU), N45 (-190HU, -45HU) respectively. Correlation and agreement of EF metrics between two models and differences between groups with coronary plaque (Plaque (+)) and without plaque (Plaque (-)) were analyzed. Results: EFV and EFA from RCCT using N30, N40 and N45 correlated well with reference (EFV: r2=0.974, 0.976, 0.972, P<0.001; EFA: r2=0.516, 0.500, 0.477, P<0.001). Threshold adjusting was able to reduce the mean difference, while increase the difference of EFA. Data measured on CCTA and RCCT both demonstrated the significantly larger EFV of Plaque (+) group than Plaque (-) group (P<0.05). The significantly difference of EFA was only shown on RCCT using N30 (Plaque (+) vs (-): -80±4.4HU vs-78±4HU, P=0.030). Conclusion: The consistency of EFV measured on RCCT could be improved through adjustment of attenuation threshold. The EFA assessment may have additional information relating to underlying pathophysiological status.
Implementation of the PADIS 2018 Guidelines: a National Multicenter Survey in the Adults Intensive Care Units in Mainland China
Authors: Zhang Fangxiao , Li Xin , Wan Xianyao , Yu Jian , Wang Hongliang , Yu Zhaoxia , Yang Yi , An Youzhong , Wu Dawei , Qian Chuanyun , Xu Yuan , Huang Qingqing , Zhao Mingyan , Zhang Dong , Ma Xiaochun , zhang Zhidan
Published: May 2021

Backgroud: In the diagnosis and treatment of critical ill patients, the management of sedation, analgesia and delirium is an indispensable part. Many guidelines provide relevant suggestion, but there is still a lack of evaluation on the compliance of medical staff. This was a national multicenter survey to assess the training frequency, the familiarity of the guidelines, prevention and management of pain, agitation/sedation, delirium, immobility, and sleep disruption in the ICU. Methods: This survey used a self-administered questionnaire online to provide data for evaluating the compliance with the PADIS guidelines. We grouped the answers that were similar in degree in order to analysis, and only complete questionnaires were included in the final analysis.Results: The respondents from 758 hospitals across 270 cities were distributed 5763 questionnaires.The response rate was 95%. Two thirds of the respondents were trained in the relevant content but only half of them had sufficient knowledge of the PADIS guidelines. The assessment frequency of pain and sedation was better than that of delirium. 83% of the respondents used physical restraint without deep sedation, 63% underwent regular treatment to improve sleep, and only 32% had opted for out-of-bed rehabilitation. Only 50% had increased family communication and early family care. The doctors provided better responses than nurses in most items, while nurses performed better in immobility, sleep disruption, and family empowerment. Also, most of the items showed better responses by University-affiliated hospitals than others, and the implementation in “large” cities with larger populations was better than that in “medium” or “small” cities.Conclusions: Most of the Chinese medical staff complied with PADIS guidelines satisfactorily, but immobility, sleep disruption, and family empowerment could be improved further. Trial registration: The survey was open and anonymous, and it was registered in the Chinese Clinical Trial Registry (Registration Number: NCT04217915. Registered 6 January 2020)
A direct comparison of ecological theories for predicting the relationship between plant traits and growth
Authors: Goud Ellie , Agrawal Anurag , Sparks Jed
Published: May 2021

Despite long-standing theory for classifying plant ecological strategies, limited data directly links organismal traits to whole-plant growth. We compared trait-growth relationships based on three prominent theories: growth analysis, Grime’s CSR triangle, and the leaf economics spectrum (LES). Under these schemes, growth is hypothesized to be predicted by traits related to biomass investments, leaf structure or gas exchange, respectively. In phylogenetic analyses of 30 diverse milkweeds (Asclepias spp.) and 21 morphological and ecophysiological traits, growth rate varied 50-fold and was best predicted by growth analysis and CSR traits, as well as total leaf area and plant height. Despite two LES traits correlating with growth, they contradicted predictions and leaf traits did not scale with root and stem characteristics. Thus, although combining leaf traits and whole-plant allocation best predicts growth, when destructive measures are not feasible, we suggest total leaf area and plant height, or easy-to-measure traits associated with the CSR classification.
Design and Implementation of 16 Quality Indices for Neonatal Screening
Authors: Chen Yao , Zeng Yinglin , Qiu Xiaolong , Lin Feng , Zhao Hong , Zhang Honghua , Chen Weifen , Lin Qingying , Liu Guanghua , Zhu Wenbin
Published: May 2021

Background: We aim to explore the realization of 16 quality control indices of neonatal disease screening in neonatal disease management information system, and to establish the multi-center management evaluation model under the framework of the whole province. Methods: Based on the network management system for neonatal screening originally used in our province, the quality management module of neonatal disease was developed and applied according to the quality control index. A quantitative evaluation method was established for the quality of all maternal and child health care institutions involved in neonatal disease screening related to neonatal disease screening, specimen collection and recall of suspected cases. Results: The quality management information was shared by all neonatal screening agencies. Comprehensive evaluation was given to the multi-center quality management measurements. Comprehensive evaluation was performed to quality among different medical institutions. Evaluation of applicability and timeliness of quality in practical work was conducted accordingly. Conclusions: The timeliness of self-improvement in centers and medical institutions were improved. The application of neonatal disease screening quality management index improved the requirements for neonatal screening management. The quality management module was adopted to conduct dynamic management of the whole management process, which greatly improved the overall management level of neonatal screening.
Leukocyte Telomere Length and Amyotrophic Lateral Sclerosis: A Mendelian Randomization Study
Authors: Xia Kailin , Zhang Linjing , Zhang Gan , Wang Yajun , Huang Tao , Fan Dongsheng
Published: May 2021

Observational studies have suggested that telomere length is associated with amyotrophic lateral sclerosis (ALS). However, it remains unclear whether this association is causal. We employed a two-sample Mendelian randomization (MR) approach to explore the causal relationship between leukocyte telomere length (LTL) and ALS based on the most cited and most recent and largest LTL genome-wide association studies (GWASs) that measured LTL with the Southern blot method (n=9190) and ALS GWAS summary data (n=80,610). We adopted the inverse variance weighted (IVW) method to examine the effect of LTL on ALS and used the weighted median method, simple median method, MR Egger method and MR PRESSO method to perform sensitivity analyses. We found that genetically determined longer LTL was inversely associated with the risk of ALS (OR=0.846, 95% CI: 0.744-0.962, P=0.011), which was mainly driven by rs940209 in the OBFC1 gene, suggesting a potential effect of OBFC1 on ALS. In sensitivity analyses, that was confirmed in MR Egger method (OR=0.647,95% CI=0.447-0.936, P=0.050), and a similar trend was shown with the weighted median method (OR=0.893, P=0.201) and simple median method (OR=0.935 P=0.535). The MR Egger analyses did not suggest directional pleiotropy, showing an intercept of 0.025 (P=0.168). Neither the influence of instrumental outliers nor heterogeneity was found. Our results suggest that genetically predicted longer LTL has a causal relationship with a lower risk of ALS and underscore the importance of protecting against telomere loss in ALS.
Hydro-climatic and Land use/cover Changes in Nasia Catchment of the White Volta Basin in Ghana
Authors: Nyadzi Emmanuel , Bessah Enoch , Kranjac-Berisavljevic Gordana , Ludwig Fulco
Published: May 2021

The Nasia catchment is the reservoir for significant surface water resources in Northern Ghana and home to numerous subsistence farmers engaged in rainfed and dry season irrigation farming. Yet there is little understanding of the hydro-climatic and land use /cover conditions of this basin. We analyzed 50 years of minimum (Tmin) and maximum temperature (Tmax), wind speed (WS), sunshine duration(S), Rainfall(R), relative humidity (RH), discharge (D) and potential evapotranspiration (PET) data, 15 years of remotely sensed normalized difference vegetation index (NDVI) data and 30 years of land use/cover image data. Results show that Tmin, Tmax, WS, and PET have increased significantly (P < 0.05). RH and S significantly declined. R, D and NDVI have insignificantly decreased (P > 0.05). A significant abrupt change in almost all hydroclimatic variables started in the 1980s, a period that coincides with the occurrence of drought events in the region except WS in 2001, R in 1968 and D in 1975. Also, D showed a positive significant correlation with RH, R and PET, but insignificant positive relationship with S. D also showed negative insignificant correlation with Tmin, Tmax and WS. Areas covered with shrubland and settlement/bare lands have increased to the disadvantage of cropland, forest, grassland and water bodies. We conclude that climate change impact is quite noticeable in the basin; indicating water scarcity and possibilities of droughts. The analysis performed herein is a vital foundation for further studies to simulate and predict the effect of climate change on the water resources, agriculture and livelihood in the Nasia basin.
Duration of Third Stage Labour and Postpartum Blood Loss: a Secondary Analysis of the WHO CHAMPION Trial Data
Authors: Chikkamath Sumangala B , Katageri Geetanjali M , Mallapur Ashalata A , Vernekar Sunil S , Somannavar Manjunath S , Piaggio Gilda , Carroli Guillermo , de Carvalho José Ferreira , Althabe Fernando , Hofmeyr G Justus , Widmer Mariana , Gulmezoglu Ahmet Metin , Goudar Shivaprasad S
Published: May 2021

Background: Obstetric haemorrhage continues to be a leading cause of maternal mortality, contributing to more than a quarter of the 2,443,000 maternal deaths reported between 2003 and 2009. During this period, about 70% of the haemorrhagic deaths occurred postpartum. In addition to other identifiable risk factors for greater postpartum blood loss, the duration of the third stage of labour (TSL) seems to be important, as literature shows that a longer TSL can be associated with more blood loss. To better describe the association between the duration of TSL and postpartum blood loss in women receiving active management of third stage of labour (AMTSL), this secondary analysis of the WHO CHAMPION trial data has been conducted.Methods: This was a secondary analysis of the WHO CHAMPION trial conducted in twenty-three sites in ten countries. We studied the association between the TSL duration and blood loss in the sub cohort of women from the CHAMPION trial defined above. We used a general linear model to fit blood loss as a function of TSL duration on the log scale, arm and center, using a normal distribution and the log link function. We showed this association separately for oxytocin and for Heat stable (HS) carbetocin.Results: For the 10,040 women analysed, blood loss rose steeply with third stage duration in the first 10 minutes, but more slowly after 10 minutes. This trend was observed for both Oxytocin and HS carbetocin and the difference in the trends for both drugs was not statistically significant (p-value=0.2070). Conclusions: There was a positive association between postpartum blood loss and TSL duration with either uterotonic. Blood loss rose steeply with TSL duration until 10 minutes, and more slowly after 10 minutes. Study registration: The main trial was registered with Australian New Zealand Clinical Trials Registry ACTRN12614000870651 and Clinical Trial Registry of India CTRI/2016/05/006969.
Toll-Like Receptors 2 and 4 Differentially Regulate the Self-Renewal and Differentiation of Spinal Cord Neural Precursor Cells
Authors: Sanchez-Petidier Marina , Guerri Consuelo , Moreno-Manzano Victoria
Published: May 2021

Background: Toll-Like Receptors (TLRs) represent critical effectors in the host defense response against various pathogens; however, their known function during development has also highlighted a potential role in cell fate determination and neural differentiation. While glial cells and neural precursor cells (NPCs) of the spinal cord express both TLR2 and TLR4, their influence on self-renewal and cell differentiation remains incompletely described. Methods: TLR2, TLR4 knock-out and the wild type mice were employed for spinal cord tissue analysis and NPCs isolation at early post-natal stage. Sox2, FoxJ1 and Ki67 expression among others served to identify the undifferentiated and proliferative NPCs; GFAP, Olig2 and b-III-tubulin markers served to identify astrocytes, oligodendrocytes and neurons respectively after NPC spontaneous differentiation. Multiple comparisons were analyzed using one-way ANOVA, with appropriate corrections such as Tukey's post hoc tests used for comparisons. Results: We discovered that the deletion of TLR2 or TLR4 significantly reduced the number of Sox2-expressing NPCs in the neonatal mouse spinal cord. While TLR2-knockout NPCs displayed enhanced self-renewal, increased proliferation and apoptosis, and delayed neural differentiation, the absence of TLR4 promoted the neural differentiation of NPCs without affecting proliferation, producing long projecting neurons. TLR4 knock-out NPCs showed significantly higher expression of Neurogenin1, that would be involved in the activation of this neurogenic program by a ligand and microenvironment-independent mechanism. Interestingly, the absence of both TLR2 and TLR4 in NPCs impeded oligodendrocyte precursor cell maturation to a similar degree. Conclusions: Our data suggest that Toll-Like receptors are needed to maintain Sox2 positive neural progenitors in the spinal cord, however possess distinct regulatory roles in mouse neonatal spinal cord NPCs - while TLR2 and TLR4 play a similar role in oligodendrocytic differentiation, they differentially influence neural differentiation.
Cationic polymer-in-salt electrolytes for fast metal ion conduction and solid-state battery applications
Authors: Chen Fangfang , Wang Xiaoen , Armand Michel , Forsyth Maria
Published: May 2021

Polymer electrolytes provide a safe solution for all-solid-state high energy density batteries. Materials that meet the simultaneous requirement of high ionic conductivity and high transference number remain a challenge, in particular for new battery chemistries beyond Lithium such as Na, K and Mg. Herein, we demonstrate the versatility of a polymeric ionic liquid (PolyIL) as a solid-state solvent to achieve this goal for both Na and K. Using molecular simulations, we predict and elucidate fast metal ion transport in PolyILs through a structural diffusion mechanism in a polymer-in-salt environment, facilitating a high transference number. Experimental validation of these computational designed Na and K polymer electrolytes gives high ionic conductivities of 1.010-3 S cm-1 at 80 oC and an exceptional Na+ transference number of ~0.57. Electrochemical cycling of a sodium anode also demonstrates an ultra-low overpotential of 40 mV and stable long term performance of more than 100 hours in a symmetric cell. PolyIL-based polymer-in-salt strategies for novel solid-state electrolytes thus offer a promising route to design high performance next generation sustainable battery chemistries.
Right-sided Endocarditis Caused by Polyclonal Staphylococcus Aureus Infection
Authors: Kolben Yotam , Ishay Yuval , Azmanov Henny , Rokney Assaf , Baum Moti , Amit Sharon , Nir-Paz Ran
Published: May 2021

We present a case of bacterial endocarditis with both methicillin-sensitive and methicillin-resistant Staphylococcus aureus, which based on typing, originated from two distinct clones. Such a case may be misinterpreted by microbiology lab automation to be a monoclonal multi-drug resistant Staphylococcus aureus, while simple microbiology techniques will instantly reveal distinct clonality.
Cultural Adaptation and Psychometric Properties of the Diabetes Quality of Life Scale in Afaan Oromoo Among People Living With Type 2 Diabetes in Ethiopia
Authors: Diriba Dereje Chala , Leung Doris Y.P. , Suen Lorna K.P.
Published: May 2021

Background: The original 46-item Diabetes Quality of Life (DQOL) scale has been translated into different languages, and the translated DQOL has shown good reliability and validity after deleting some items. However, the DQOL is not available in the Afaan Oromoo language for people living with type 2 diabetes (T2D) in Ethiopia. The objective of the study was to translate the DQOL scale into Afaan Oromoo, and to culturally adapt and evaluate the psychometric properties of the DQOL-Afaan Oromoo (DQOL-AO) among people living with T2D in Ethiopia.Methods: A cross-sectional study with a convenience sampling technique was conducted in 2020. The DQOL was translated and adapted to Afaan Oromoo. Item-total correlations and exploratory factor analysis (EFA) assessed factor structure; the Cronbach’s alpha assessed internal consistency and relationships with gender, educational status, marital status, age, employment status; and status of diabetes-related disease assessed the construct validity of the DQOL-AO.Results: A 417 participants responded to all items of the DQOL. Item-total correlation analysis and EFA produced a 34-item DQOL-AO with four subscales, which demonstrated that the internal consistency of the overall DQOL-AO was 0.867, and scores were 0.827, 0.846, 0.654, 0.727 for the impact, satisfaction, social/vocational worry, and diabetes-related worry subscales, respectively. Statistically significant differences in QOL were obtained in educational status (F=7.164, p<0.001) and employment status (F=4.21, P=0.002). Individuals who attended college and above and government employees had better QOL. Conclusion: The 34-item DQOL-AO provided preliminary evidence as a reliable and valid tool to measure diabetic-related QOL among adults living with T2D who speak Afaan Oromoo.
An Exploratory Cohort Study of the Association Between the Level of Testosterone and Suicidal Ideation in the Hospitalized Adolescent Female With Depression in China
Authors: Liu Yan , Wang Shaohua , Xue Chuang , Hu Xiwen , Zhou Guoling , Zhou Yuanyue , Fang Dan , Ding Kaijing , Chen Wencong
Published: May 2021

BackgroundTo date, around 4 per 100, 000 adolescent committed suicide within the 29 OECD countries. The suicidal behavior is related to psychological factors, genetics, neurobiology, and other biomarkers. We aimed to investigate the risk factors for the suicidal ideation, especially the association between suicide ideation and different levels of testosterone in the adolescent female with depression. The goal of this study is to aid the development of strategies to intervene the suicidal behavior for the depressed female adolescent. MethodIn this single center, prospective cohort study, we enrolled adolescent female with depression. We collected baseline demographic data, age adjusted level of testosterone, Symptom Self-rating Scale, and information about the suicidal ideation, non-suicidal self-injury (NSSI), and suicide attempt. We used multivariate logistic regression to determine the risk factors for the suicidal ideation. ResultsTotal 113 hospitalized adolescent female enrolled with a mean age of 13.5 (1.20). Among these patients, there were 86 (76.1%) subjects suffered from the suicidal ideation, while 59 (52.2%) of them had NSSI and 23 (20.4%) had suicide attempt behavior. In the final model, higher level of testosterone (p = 0.04) and higher age (p = 0.02) were associated with the higher odds of having suicidal ideation.ConclusionIn this exploratory cohort study, suicidal ideation was prevalent. It is important to assess the level of testosterone in the adolescent female with depression. This study is consistent with the other studies. It shows the age is a potential predictor for the suicidal ideation in the hospitalized adolescent female with depression.
Differences in Adverse Events Related to Voluntary Male Medical Circumcision Between Civilian and Military Health Facilities in Uganda
Authors: Obangaber Lucky Ogweng , Seruwagi Gloria , Nabaggala Maria Sarah , Lugada Eric , Bwayo Denis , Nyanzi Abdul , Rwegyema Twaha , Wamundu Cassette , Lawoko Stephen , Kasujja Vincent , Asiimwe Evarlyne , Musinguzi Ambrose , Kikaire Bernard , Kiragga Agnes
Published: May 2021

Background: Voluntary medical male circumcision (VMMC) significantly reduces the risk of acquiring HIV in men. Despite the percentage of circumcised men (15-49 years) in Uganda increasing over time, some populations are not taking up the surgical procedure. The government of Uganda and implementing partners have responded to this lack of VMMC coverage among key populations by intensifying introducing innovative strategies that increase demand particularly among military personnel using the WHO’s MOVE strategy. As a surgical intervention, it is critical that VMMC services are safe for clients and that adverse events or complications are minimized. This paper describes the prevalence and trends of adverse events reported among military mobile camps in comparison to civilian sites in Uganda. Methods: A prospective study conducted in eighteen (18) public health facilities between March and August 2019. Of these nine (9) were providing care to civilian populations while nine (9) served the military population and catchment areas. Descriptive statistics, Chi-square test and trends analysis were carried out to describe profile of advance events among civilian and military facilities over the study period. Results: The highest proportions of VMMC were done among persons aged 15 to 19 years whereas among military camps the highest proportions of circumcision among males aged 20 to 24 years. Regarding site of circumcision, the highest proportions of VMMC were done at outreaches, with higher levels in military camps compared to civilian camps. For the proportions of adverse events reported, higher proportions were reported in civilian camps compared to military camps (Total – 1.3% vs 0.2%; p- value<0.05). For trends analysis, results indicate that there was no statistically significant trend for both civilian and military number of adverse events reported for the four quarters in 2020 (P-value =0.315 for civilian and P=0.094 for the military). Conclusions: The MOVE model is great for scaling up VMMC in specialized populations such as military. Can also be adapted in other populations if contextual bottlenecks are identified and collectively addressed by key stakeholders – leadership, community engagement and using a largely horizontal approach offer promising possibilities and outcomes.
A meta-analysis of effects of blended learning on performance, attitude, achievement, and engagement in different countries
Authors: Yu Zhonggen
Published: May 2021

Although the new century has been witnessing increasing popularity of blended learning especially during this special pandemic time, few studies have summarized the effectiveness of blended learning in different countries. This meta-analysis summarizes previous studies on blended learning effectiveness in different countries in terms of students’ performance, students’ attitudes towards blended learning, learning achievement, and student engagement in different countries. Through the meta-analysis via Stata/MP 14.0, it is concluded that blended learning could improve performance, attitude, and achievement in most countries. However, in both China and the USA, blended learning could not significantly improve student engagement in academic activities. No significant differences were revealed in student performance in the USA between blended and non-blended learning. Future research could extend the research into blended learning to more countries and areas across the world.
Interaction Between Income, Health Insurance, and Self-rated Health: a Path Analysis
Authors: West Atalie Ashley , Unruh Lynn
Published: May 2021

Aim: The public health literature suggests health insurance and socioeconomic status (SES) are independent predictors of health outcomes; few studies have explored the interrelationships between these predictors and health. This study explores relationships between income, health insurance, and health, testing the following hypotheses: 1) people with health insurance have higher self-rated health than those who do not; 2) people who have higher income are more likely to have both insurance and higher self-rated health.Subject and Methods: This is retrospective, cross-sectional, secondary data analysis of 39,450 records from the 2016 National Health Interview Survey (NHIS). The design utilizes path analysis to simultaneously assess relationships between health insurance status, income, and self-rated health, along with several socio-demographic covariates.Results: We find that higher income and having insurance were both significant predictors of higher self-rated health. Income had a stronger direct effect on health than being insured, as indicated by standardized coefficients. Higher income was also related to having health insurance, thereby influencing health indirectly through its relationship with health insurance. Several socio-demographic variables were also related to self-rated health, income, and insurance. Conclusions: Future research should explore effects of both insurance and income and their interrelationships on health. Health policies should consider that growing poverty and income inequality in the U.S. limit the effectiveness of health insurance and other social programs if larger social conditions are not addressed.
Utility of Cardiopulmonary Exercise Testing (CPET) in the Post-COVID-19 Context: Retrospective Analysis of a Single Centre Experience.
Authors: Parkes Edward , Shakespeare Joanna , Robbins Timothy , Kyrou Ioannis , Randeva Harpal , Ali Asad
Published: May 2021

Cardiopulmonary exercise testing (CPET) allows objective assessment of a patient’s global response to maximal incremental exercise. CPET has been proposed to have a role in investigating post-COVID syndrome. However, CPET is resource intensive, and essential for restoration of other clinical services (e.g. cancer surgery). The aim of this study was to explore utility of CPET in assessing functional status of COVID-19 survivors with persistent dyspnoea.
Of the 600 patients reviewed in a post-COVID-19 assessment clinic between May 2020 and April 2021, 12 (male/female: 8/4; age: 4±15.2 years; BMI: 32.8±5.9 kg/m2; non-smokers/ smokers: 8/4) were referred for CPET due to persistent breathlessness out-keeping with disease severity. Of these patients, 10 patients demonstrated reduced peak VO2, whilst five had an exercise limitation attributed to physical deconditioning. Two patients had mainly a cardiac limitation to exercise, with a further three patients demonstrating breathing pattern disorder, pulmonary vascular disease and lung disease.
The findings of this single-centre study suggest that intensive CPET testing may not add substantial additional clinical information to aid patient investigation/management in the context of post-COVID. Such resource intensive procedures may be better utilised in selected patients and in the restoration of NHS services following the COVID-19 pandemic.
Using genetics to uncouple higher adiposity from its adverse metabolic effects and understand its role in metabolic and non-metabolic disease.
Authors: Yaghootkar Hanieh , Martin Susan , Tyrrell Jessica , Thomas Elizabeth , Bown Matthew , Wood Andrew , Beaumont Robin , Tsoi Lam , Stuart Philip E , Elder James , Law Philip , Houlston Richard , Kabrhel Christopher , Papadimitriou Nikos , Gunter Marc , Bull Caroline , Bell Joshua , Vincent Emma , Sattar Naveed , Bell Jimmy , Frayling Timothy
Published: May 2021

To understand the consequences of higher adiposity uncoupled from its adverse metabolic effects, we selected 37 diseases associated with obesity and genetic variants associated with different aspects of excess weight including metabolically “favourable adiposity” (FA) and “unfavourable adiposity” (UFA). Mendelian randomisation (MR) identified two sets of diseases. First, 12 conditions where the metabolic effect of higher adiposity is the likely primary cause of the disease. Here MR with the FA and UFA genetics showed opposing effects on the risk of disease, including colorectal and ovarian cancer, and gout. Second, 7 conditions where the non-metabolic effects of excess weight (e.g. mechanical effect) is likely a cause. Here MR with the FA genetics, despite leading to lower metabolic risk, and MR with the UFA genetics, were both associated with higher disease risk, including osteoarthritis and venous thromboembolism. Individuals with high BMI are at higher risk of some diseases despite being relatively metabolically healthy.
Blocking PSD-93-CX3CL1 Interaction Promotes Phenotypic Polarization Transformation of Microglia During Acute Ischemic Stroke Injury
Authors: Zhang Qingxiu , Cao Xiaowei , Yang Hui , Liu Xiaomei , Lou Shiying , Kong Liping , Rong Liangqun , Shan Junjun , Xu Yun
Published: May 2021

Background：Postsynaptic density 93 (PSD-93) plays an important role in ischemic brain injury through mediating neurotoxicity and neuroinflammation. Blocked the combination of PSD-93 and Fractalkine (CX3Cchemokineligand1, CX3CL1) play beneficial roles in acute ischemic stroke. However, the underlying mechanism still need further exploration. Methods：In this study, male C57BL/6 mice aged 8-12 weeks and weighted 22-26g were applied with Middle Cerebral Artery Occlusion (MCAO) model and randomly divided into different groups. Firstly, real-time quantitative PCR was to detect some cytokines associated with M1 and M2 type of microglia at different time points in transient MCAO model. Secondly, triphenyl tetrazolium chloride (TTC) staining, brain water content and behavioral assessments were used to evaluate the neurologic damage. Immunofluorescence staining was performed to measure the white matter injury, and microglia polarization. Moreover, enzyme-linked immunosorbent assay (ELISA) was used to investigate the expression of soluble CX3CL1. Results：M1 phenotype cytokines were detected at different time points and found that their expression increased from beginning at 6 hours after reperfusion and most peaked at 24 h after reperfusion. However, the expression of M2 phenotype cytokines decreased or still keep invariant at 6 hours and 24 h after reperfusion. Interestingly, Tat-CX3CL1 (357-395aa) can facilitate microglia polarization from M1 type to M2 type through inhibiting expression of the soluble CX3CL1. Furthermore, CX3CL1 specific cleavase inhibitor ADAM17 could restrain the microglia polarization transformation via reducing the soluble CX3CL1 formation. Moreover, Tat-CX3CL1 (357-395aa) also attenuate long-term cognitive deficits and improved white matter integrity. Conclusions: In conclusion, we demonstrated that specific blockage the binding of PSD-93 and CX3CL1 by Tat-CX3CL1 (357-395aa) could perform functional recovery after ischemic stroke by promoting type microglia polarization transformation from M1 to M2. And the peptide Tat-CX3CL1 (357-395aa) is a promising strategy for treatment of ischemic stroke.
Nanoscale Imaging of Phonon Dynamics by Electron Microscopy
Authors: Pan Xiaoqing , Gadre Chaitanya , Yan Xingxu , Song Qichen , Li Jie , Gu Lei , Aoki Toshihiro , Lee Sheng-Wei , Chen Gang , Wu Ruqian
Published: May 2021

Spatially resolved vibrational mapping of nanostructures is indispensable to the development and understanding of thermal nanodevices1, modulation of thermal transport2, and novel nanostructured thermoelectric materials3–5. Through the engineering of complex structures such as alloys, nanostructures, and superlattice interfaces, one can significantly alter the propagation of phonons and suppress material thermal conductivity while maintaining electrical conductivity2. Probing local vibrations and phonon dispersions in nanostructured semiconductors informs structure-property correlations and offers insights into the design and optimization of novel thermoelectric materials. There have been no correlative experiments that spatially track the modulation of phonon properties in and around nanostructures due to spatial resolution limitations of conventional optical phonon detection techniques. Here we demonstrate two-dimensional spatial mapping of phonons in a single silicon-germanium (SiGe) quantum dot (QD) using monochromated electron energy loss spectroscopy (EELS) in the transmission electron microscope (TEM). Tracking the variation of the Si optical mode in and around the QD, we observe the nanoscale modification of the composition induced redshift. We observe nonequilibrium phonons that only exist near the interface and furthermore, develop a novel technique to differentially map phonon momenta providing direct evidence that the interplay between diffusive and specular reflection largely depends on the detailed atomistic structure --a major advancement in the field. Our work unveils the nonequilibrium phonon dynamics at nanoscale interfaces and can be used to study actual nanodevices and aid in the understanding of heat dissipation near nanoscale hotspots, which is crucial for future high-performance nanoelectronics. Our work demonstrates high spatial resolution vibrational characterization of nanostructures and interfaces that can be extended to other nanostructures and superlattice systems, in terms of composition, composition gradient, and structure driven phonon dynamics.
The Effect of Health Expenditure and Immunisation on Under-Five Mortality Rate in Selected African Countries.
Authors: EBOH Alfred , METIBOBA Steve
Published: May 2021

Background: As a way of tackling child mortality, many countries in the world depend on their respective health-care system. But governments of most countries in Africa are yet to provide robust funding of their health-care systems as many people still depend on the out-of-pocket payment to receive health services. Against this backdrop, this study used annual panel data to assess the effect of health-care expenditure and immunisation on the under-five mortality rate in 30 selected African countries for the period 2000-2017. Methods: Multiple regression technique was adopted for the data analysis and the robust fixed regression estimator was preferred to the random effects as determined by Hausman test.Results: The findings indicated that domestic government general health expenditure had a significant negative effect on the under-five mortality rate. However, the effect of domestic private health expenditure on under-five mortality was not significant while external health expenditure had a significant negative effect on under-five mortality rate. The impact of diphtheria immunisation on under-five mortality was significant. Conclusions: Except domestic private health expenditure, government and external forms of health expenditure coupled with diphtheria immunisation were significant factors for the reduction of the under-five mortality in the selected countries.
Features Associated With Contagiousness Among COVID-19 Cases in Shanghai, China
Authors: Kong Dechuan , Fang Qiwen , Wu Huanyu , Hu Linjie , Wagner Abram L. , Lu Yihan , Zheng Yaxu , Gong Xiaohuan , Zhu Yiyi , Jin Bihong , Xiao Wenjia , Mao Shenghua , Lin Sheng , Han Ruobing , Yu Xiao , Cui Peng , Jiang Chenyan , Pan Hao , Sun Xiaodong
Published: May 2021

Background: Little is known about the characteristics of those who transmit SARS-CoV-2 infection vs those who do not, but this information could inform disease control policies. This study described the features of clusters in the first wave of COVID-19 in Shanghai and compared contagiousness by clinical and health care risk factors.Methods: In this retrospective cohort study of cases in Shanghai in January and February 2020, cases with successive generations were considered to be “contagious.” Characteristics of contagious and non-contagious cases were compared in log-binomial models that also adjusted for age and sex. Results: Between January 21 and February 17, 2020, 333 cases of COVID-19 were reported in Shanghai across 28 known infection chains. Contagiousness was higher among cases with a sore throat (risk ratio [RR]: 3.41, 95% CI: 1.59, 7.35, P=0.0051), and those with heart disease (RR: 2.06, 95% CI: 0.72, 5.90). Delays in diagnosis were also associated with higher risk of contagiousness. Having ≥2 medical visits before diagnosis was associated with 4.46 times higher risk of contagiousness (95% CI: 2.03, 9.83, P=0.0002), and there was a non-significant increase in risk with increasing numbers of days between disease onset and isolation (for each day, RR: 1.08, 95% CI: 1.01, 1.16, P=0.1734).Conclusions: Individuals with mild COVID-19 symptoms in the upper respiratory tract may still be contagious, and such individuals should be prioritized for early diagnosis and isolation to limit further chains of transmission.
Genome Mining of Secondary Metabolites From a Marine-derived Aspergillus Terreus B12
Authors: du xinyang , Li Huanhuan , Qi Jiangfeng , Chen Chaoyi , Lu Yuanyuan , Wang Ying
Published: May 2021

As an important saprophytic filamentous fungus, Aspergillus terreus is ubiquitously distributed, including soil rhizospheres and marine environments. Due to the prominent capabilities of bioconversion and biosynthesis, A. terreus has become attractive in biotechnical and pharmaceutical industry. In this work, an A. terreus strain, B12, was isolated from sponge in South China Sea, which demonstrated broad bacteriostatic effects against a variety of pathogenic bacteria. The whole genome was sequenced, showing a genetic richness of BGCs, which might underpin the metabolic plasticity and adaptive resilience for the strain. Genome mining identified 67 biosynthetic gene clusters (BGCs), among which, 6 gene clusters could allocate to known BGCs (100% identity), corresponding to diverse metabolites like clavaric acid, dihydroisoflavipucine /isoflavipucine, dimethylcoprogen, alternariol, aspterric acid and pyranonigrin E. However, instead of the putative compounds, several other products were obtained from the B12 fermentation, including terrein, butyrolactone I, terretonin A&E, acoapetaline B and epi-aszonalenins A. Of note, acoapetaline B and epi-aszonalenins A, discovered natural products recently with little information, unexpectedly were reported in this A. terreus strain. The genomic and heterogeneity observed in strain B12, should be at least partially attributed to the genetic variability and biochemical diversity of A. terreus , which could be an interesting issue open to future efforts.
Advancing Scalability and Impacts of a Teacher Training Program for Promoting Child Mental Health in Ugandan Primary Schools: Protocol for a Hybrid-Type II Effectiveness-Implementation Cluster Randomized Trial
Authors: Huang Keng-Yen , Nakigudde Janet , Kisakye Elizabeth Nsamba , Sentongo Hafsa , Dennis-Tiwary Tracy A , Tozan Yesim , Park Hyung , Brotman Laurie Miller
Published: May 2021

Background: There are numerous challenges to promoting child mental health in low-and-middle income countries (LMICs). Most evidence-based interventions (EBIs) adapted to LMICs have not been scaled widely or evaluated for effectiveness and underlying mechanisms. Most mental health EBIs in LMICs rely on a task-shifting approach of implementation because of the shortage of mental health professionals; however, challenges related to task-shifting are understudied. Most EBIs have not been implemented using a scalable and sustainable model that leverages and strengthens existing structures. Through a cross-sector collaboration, we are carrying out a second generation investigation of implementation and effectiveness of a school-based mental health EBI for early childhood students that uses task-shifting and builds on existing educational structures. The ultimate shared goal of this collaboration is to scale and sustain the EBI country wide. The systems-level approach to promoting child mental health builds on ParentCorps, an EBI implemented in schools that has been shown in multiple trials to yield long-term benefits on mental health and school performance. Previous studies in Uganda found that ParentCorps Professional Development (PD) for teachers resulted in short-term benefits for classrooms, children and families. Objectives: This paper describes the rationale and protocol for an effectiveness-implementation study of ParentCorps-PD for teachers in urban and rural Ugandan schools. The study considers the added value (i.e. impact and costs) of a brief wellness intervention for teachers in their task-shifting role and explores mechanisms and outcomes. Methods: Using a hybrid-type II effectiveness-implementation cluster randomized controlled trial (cRCT), we will randomize 36 schools (18 urban and 18 rural) with 540 teachers and nearly 2,000 families to one of three conditions: PD + Teacher-Wellness (PDT), PD alone (PD), and control. Primary effectiveness outcomes are teachers’ use of mental health promoting strategies, teacher stress management, and child mental health. Mixed methods will be employed to examine underlying mechanisms of implementation and impact as well as cost-effectiveness. Discussion: This research will generate important knowledge regarding the value of an EBI in urban and rural communities in a LMIC, and efforts toward supporting teachers who are task-shifting as a potentially cost-effective strategy for promoting child mental health. Trial Registration: This trial was registered with ClinicalTrials.gov (registration number: NCT04383327; https://clinicaltrials.gov/ct2/show/NCT04383327) on May13, 2020.
Research on Chip Formation Mechanism and Surface Morphology of Particle-reinforced Metal Matrix Composites
Authors: Fang Yuxin , Wang Youqiang , Zhang Ping , Luo Heng
Published: May 2021

In this paper, a finite element (FE) cutting model for particle-reinforced metal matrix composites (PRMMCs) considering material damage was developed to predict SiC particle failure, cutting forces and machined surface topography in SiCp/Al composite machining, and to analyze the dynamic mechanisms of chip formation and particle failure evolution. The validity of the simulation model was verified by comparing the simulation results with the cutting forces and surface topography obtained from the milling machining experiments. It was found that complex stress-strain fields exist in SiCp/Al composites with mesoscopic non-homogeneous structures, and alternating reticulation of tensile and compressive stress between particles was observed; particle failure due to tool-workpiece interaction exists in both direct and indirect ways; particle failure and local chip deformation during machining affect surface topography and chip shaping, resulting in serrated chips, pitting on the machined surface, and residual particle fragments.
Characteristics of New Permanent Magnetic Eddy Current Drive System of the Scraper Conveyor
Authors: wang shuang , GUO Yongcun , LI Deyong
Published: May 2021

This study provides a new permanent magnetic eddy current drive system to solve the ener-gy-saving drive problem of the scraper conveyor working under bad conditions, including overload startup, severe abrasion and pollution. Considering the practical conveying conditions of the scraper chain on a fully mechanised coal mining face, this study creates a mathematical model for the new permanent magnetic eddy current drive system of the scraper conveyor based on its characteristics and indicates the motion characteristics of the scraper chain driven by two wheels. This study verifies the model accuracy with a pre-startup technology depending on the scraper conveyor on the No. 12318 working face of the 8th coal mine in the West No. 1 mining area of the Pansan Coal Mine of the Huainan Mining Group. According to the results, the motion acceleration of the scraper chain based on the new permanent magnetic eddy current drive is lower than that of the scraper chain with a hydraulic coupler under the same running condition and load during startup and acceleration and declines by approximately 14.7%. Consequently, this can decline the startup impact due to the serious abrasion and frequent overload of the scraper chain working under bad conditions.