bluuebunny/crossref_metadata_2025 huggingface dataset:
Risk and protective factors associated with grandparent kinship caregivers' psychological distress in COVID‐19: Kinship license status as a moderator
Authors: Xu Yanfeng , Jedwab Merav , Wu Qi , Levkoff Sue E. , Xu Ling
Published: July 2021

COVID‐19 and its related policy measures have increased the psychological distress of individuals, including grandparent kinship caregivers. Guided by the Resilience Model of Family Stress, Adjustment, and Adaptation, this study examines relationships between material hardship, parenting stress, social support, resilience and psychological distress of grandparent kinship caregivers during the COVID‐19 pandemic, as well as the moderating role of kinship license status on these relationships. Kinship care licensing is a prerequisite to receiving financial assistance and other supporting services from the government. We administered a cross‐sectional survey of grandparent kinship caregivers (N = 362) in the United States. Logistic regression results indicated that material hardship was associated with higher odds of experiencing psychological distress, whereas resilience and social support were associated with lower odds. Kinship license status moderated the relationships of social support and resilience with psychological distress. Results suggest that additional emergency funds and more tailored financial services should be provided to meet material needs, and interventions with a focus on resilience and social support are particularly needed. The moderating effects of license status indicate that some interventions should be specifically implemented among licensed kinship caregivers, whereas parallel services should be provided to kinship caregivers regardless of their license status.
Clinical and genetic spectrum of 104 Indian families with central nervous system white matter abnormalities
Authors: Kaur Parneet , do Rosario Michelle C , Hebbar Malavika , Sharma Suvasini , Kausthubham Neethukrishna , Nair Karthik , A Shrikiran , Bhat Y Ramesh , Lewis Leslie Edward S , Nampoothiri Sheela , Patil Siddaramappa J , Suresh Narayanaswami , Bijarnia Mahay Sunita , Dua Puri Ratna , Pai Shivanand , Kaur Anupriya , KC Rakshith , Kamath Nutan , Bajaj Shruti , Kumble Ali , Shetty Rajesh , Shenoy Rathika , Kamate Mahesh , Shah Hitesh , Muranjan Mamta N , BL Yatheesha , Avabratha K Shreedhara , Subramaniam Girish , Kadavigere Rajagopal , Bielas Stephanie , Girisha Katta Mohan , Shukla Anju
Published: July 2021

Genetic disorders with predominant central nervous system white matter abnormalities (CNS WMAs), also called leukodystrophies, are heterogeneous entities. We ascertained 117 individuals with CNS WMAs from 104 unrelated families. Targeted genetic testing was carried out in 16 families and 13 of them received a diagnosis. Chromosomal microarray (CMA) was performed for three families and one received a diagnosis. Mendeliome sequencing was used for testing 11 families and all received a diagnosis. Whole exome sequencing (WES) was performed in 80 families and was diagnostic in 52 (65%). Singleton WES was diagnostic for 50/75 (66.67%) families. Overall, genetic diagnoses were obtained in 77 families (74.03%). Twenty‐two of 47 distinct disorders observed in this cohort have not been reported in Indian individuals previously. Notably, disorders of nuclear mitochondrial pathology were most frequent (9 disorders in 20 families). Thirty‐seven of 75 (49.33%) disease‐causing variants are novel. To sum up, the present cohort describes the phenotypic and genotypic spectrum of genetic disorders with CNS WMAs in our population. It demonstrates WES, especially singleton WES, as an efficient tool in the diagnosis of these heterogeneous entities. It also highlights possible founder events and recurrent disease‐causing variants in our population and their implications on the testing strategy.
Impact of risk‐stratified mycophenolate dosing in heart transplantation
Authors: Alam Amit , Van Zyl Johanna S. , Hall Shelley A. , Sam Teena
Published: July 2021

Mycophenolate mofetil (MMF), the prodrug of mycophenolic acid, is a highly effective immunosuppressive agent in heart transplant therapy. While the FDA approved dose is 1500 mg twice daily, dosing is often reduced due to dose‐dependent adverse effects. However, empiric MMF dose reductions may lead to sub‐therapeutic dosing and impair clinical outcomes. Our single center protocolized a risk‐stratified approach based on age and weight to dose 500 mg twice daily or 1000 mg twice daily to patients after heart transplantation. This retrospective single‐center study analyzed 140 consecutive heart transplant patients who were initiated on our risk‐stratified MMF protocol post‐transplant. The analysis revealed that the composite rate of biopsy‐proven rejection, graft loss, or mortality at 1‐year post‐transplantation was similar between the two groups. Incidence of neutropenia, thrombocytopenia, infection, cardiac allograft vasculopathy, or acute kidney injury by 1‐year also showed similar results between the two groups. Risk‐stratification of MMF dosing appears to be a safe and effective strategy after heart transplantation.
Assessing Muslim women’s power: Islamism, political engagement, and the gender gap
Authors: Shaykhutdinov Renat , Achilov Dilshod
Published: July 2021

What explains the gender gap in collective political activism in the Muslims world? Under what conditions do Muslim women actively engage in mass political activism? Utilizing the World Values Survey (2010–2012; n = 19,616) and shifting the theoretical focus on the largely ignored meso‐level of analysis of organizational effects, this study conducts a two‐level analysis to (1) chart and reassess the gender gap and (2) analyze the extent to which the gender gap shapes collective political activism in 16 Muslim‐majority states. It probes the variation of protest engagement of women at individual, institutional, and state levels. Our findings suggest that while men appear more likely, on average, to engage in collective action, women with high associational social capital appear more likely than women and men without such capital to embark on collective protests in Muslim‐majority states. Notably, active engagement in civil society social networks emerges as a robust predictor of political engagement, suggesting that associational social capital remains an important factor of motivation and vehicle for mass political activism, particularly among Muslim women.
The effect of microglial inhibition on the expression of BDNF, KCC2, and GABAA receptor before and after the establishment of CCI‐induced neuropathic pain model
Authors: Zarei Malek , Sabetkasaei Masoumeh , Moini Zanjani Taraneh , Sahebi Vaighan Navideh
Published: July 2021

Damage to the peripheral or central nervous system results in neuropathic pain. Based on a complicated mechanism, neuropathic pain has no efficient treatment so far. It has been well‐known that the expression of some proteins (BDNF, KCC2, GABA‐A) during neuropathic pain changes. Microglial cell activation is considered as a trigger to alter the expression of these proteins. In the current study, the effect of minocycline as a potent microglial activation inhibitor on the gene and protein expression of these neuropathic pain mediators was investigated. This experiment was done in two paradigms, preinjury and postinjury administration of minocycline. In each paradigm, male Wistar rats (weight 150–200 g, n = 6) were allocated to sham, control, and drug groups. Minocycline (30 mg/kg, i.p.) was injected 1 h before or at day seven after nerve injury and continued till day 14 in the preemptive or postinjury part of the study, respectively. After the last injection, the animals were decapitated and the lumbar part of the spinal cord was isolated to assess the expression of genes and proteins of interest. In the preventive study, minocycline increased the expression of KCC2 and GABA‐A/γ2 proteins and decreased BDNF expression. On the other hand, the target gene expression and protein expression were not changed when minocycline was administered after nerve injury. It seems that minocycline was able to change the expression of proteins of interest merely when used before nerve damage.
Synthesis reveals that island species–area relationships emerge from processes beyond passive sampling
Authors: Gooriah Leana , Blowes Shane A. , Sagouis Alban , Schrader Julian , Karger Dirk N. , Kreft Holger , Chase Jonathan M.
Published: July 2021

Aim

The island species–area relationship (ISAR) quantifies how the number of species increases as the area of an island or island‐like habitat gets larger and is one of the most general patterns in ecology. However, studies that measure the ISAR often confound variation in sampling methodology and analyses, precluding appropriate syntheses of its underlying mechanisms. Most ISAR studies use only presence–absence data at the whole‐island scale, whereas we planned to use a framework that applies individual‐based rarefaction to synthesize whether and how the ISAR differs from the null expectation of the passive sampling hypothesis.

Location

Five hundred and five islands from 34 different archipelagos across the world, including oceanic islands, lake islands and forest islands.

Major taxa studied

Local assemblages of plants, invertebrates, herpetofauna, birds and mammals.

Methods

We collated local‐scale species abundance data from multiple archipelagos (median of 12 islands per study) and used a rarefaction‐based approach to synthesize the relationship between island size and (1) sample effort‐controlled rarefied species richness, or (2) an effective number of species derived from the probability of interspecific encounter (an index of community evenness).

Results

When we applied rarefaction to control for sampling effort, the numbers of species and their relative abundances across all studies differed from the passive sampling hypothesis. Our measure of evenness also increased with island size, suggesting that the disproportionate effects we observed influenced both rarer and more common species. We found few associations between the slope of this effect and island type or taxon, but we did find that island archipelagos with greater elevational heterogeneity also deviated more from the null expectation than those with less heterogeneity.

Main conclusions

Using a synthetic approach across island archipelagos, we reject the null expectation that passive sampling causes the ISAR and instead suggest that ecological mechanisms leading to disproportionate (non‐random) effects on larger relative to smaller islands are predominant.
Research, curation, and writing differently—A review of Aesthetics, Organization, and Humanistic Management
Authors: Slater Ruth Elizabeth
Published: July 2021

This is a review of the book edited by Kostera and Woźniak (2020) which showcases the novel ways the combination of aesthetics and humanistic management can enhance research in organization and management. The purpose of such an endeavour is to provide more valuable and actionable insight into the human condition, improve human dignity and promote human understanding and flourishing. Over 15 chapters, this book showcases a wide range of research and investigation through various forms of human esthetic endeavor. The chapters are discrete and the research uses methods involving aesthetics to inquire or concern art in its widest sense to enhance understanding and optimize sense‐making for all organizational members. The latter is an activity that all humans should enjoy to promote human flourishing and many of the chapters engage in this way.
Increased risk of catheter‐related infection in critically ill patients given catecholamine inotropes during continuous renal replacement therapy
Authors: Liu Xiaotian , Ye Hongjian , Zheng Xunhua , Zheng Zhihua , Chen Wei , Yu Xueqing
Published: July 2021

Introduction

Previous in vitro studies have shown that catecholamine inotropes are potent stimulators of bacterial growth and biofilm formation on catheter surfaces. This study aimed to investigate the effects of administering catecholamine inotropes during continuous renal replacement therapy (CRRT) on catheter‐related infections in critically ill patients.

Methods

This single‐center retrospective cohort study included patients requiring CRRT in an intensive care unit from 2016 to 2017, who were divided into those who received and did not receive catecholamine inotropes for ≥24 h (catecholamine and control groups, respectively). The primary endpoint was catheter‐related infection, including catheter‐related colonization (CRCOL) and catheter‐related bloodstream infection (CRBSI).

Findings

We included 235 patients with 297 dialysis catheters. The catecholamine group had higher proportions of cardiovascular disease (p = 0.002), shock (p < 0.001), mechanical ventilation (p < 0.001), and antibiotic use (p = 0.013). There was no significant between‐group difference in the CRBSI incidence (5.742 vs. 3.143 events/1000 catheter‐days; p = 0.205). However, the CRCOL incidence was significantly higher in the catecholamine group than in the control group (6.221 vs. 0.898 events/1000 catheter‐days; p = 0.006). The prominent pathogenic bacteria were gram‐negative bacteria. After adjusting for confounding factors in multivariate logistic models, catecholamine inotropes (OR: 3.575, 95% CI: 1.422–9.912, p = 0.008) and immunosuppression (OR: 2.980, 95% CI: 1.137–7.812, p = 0.026) were independently associated with a higher risk of catheter‐related infections.

Discussion

We observed a similar incidence of catheter‐related infection with that in other CRRT patients. Using catecholamine inotropes in those patients increased CRCOL risk, which is consistent with previous in vitro studies. Our findings suggest that catecholamine inotropes is an independent risk factor for catheter‐related infections in critically ill patients undergoing CRRT.
COVID‐19 disparities by gender and income: Evidence from the Philippines
Authors: LAVADO Rouselle F. , NOWACKA Keiko , RAITZER David A. , RODGERS Yana van der Meulen , ZVEGLICH Joseph E.
Published: July 2021

The COVID‐19 pandemic and the resulting containment policies have hit the Philippines harder than most developing countries. The government lockdown is among the strictest in the world, and blanket school closures are the lengthiest. This article uses a novel simulation model to estimate the gendered and regional impacts of these factors on labour, income and poverty, and a case study of school closures points to the losses in employment among private school teachers and in the income of parents with young children. The authors find that the pandemic has had unprecedented implications for economic activity and has disproportionately affected women.
Balancing selection and wild gene pool contribute to resistance in global rice germplasm against planthopper
Authors: Zhou Cong , Zhang Qian , Chen Yu , Huang Jin , Guo Qin , Li Yi , Wang Wensheng , Qiu Yongfu , Guan Wei , Zhang Jing , Guo Jianping , Shi Shaojie , Wu Di , Zheng Xiaohong , Nie Lingyun , Tan Jiaoyan , Huang Chaomei , Ma Yinhua , Yang Fang , Fu Xiqin , Du Bo , Zhu Lili , Chen Rongzhi , Li Zhikang , Yuan Longping , He Guangcun
Published: July 2021

Interactions and co‐evolution between plants and herbivorous insects are critically important in agriculture. Brown planthopper (BPH) is the most severe insect of rice, and the biotypes adapt to feed on different rice genotypes. Here, we present genomics analyses on 1,520 global rice germplasms for resistance to three BPH biotypes. Genome‐wide association studies identified 3,502 single nucleotide polymorphisms (SNPs) and 59 loci associated with BPH resistance in rice. We cloned a previously unidentified gene Bph37 that confers resistance to BPH. The associated loci showed high nucleotide diversity. Genome‐wide scans for trans‐species polymorphisms revealed ancient balancing selection at the loci. The secondarily evolved insect biotypes II and III exhibited significantly higher virulence and overcame more rice varieties than the primary biotype I. In response, more SNPs and loci evolved in rice for resistance to biotypes II and III. Notably, three exceptional large regions with high SNP density and resistance‐associated loci on chromosomes 4 and 6 appear distinct between the resistant and susceptible rice varieties. Surprisingly, these regions in resistant rice might have been retained from wild species Oryza nivara. Our findings expand the understanding of long‐term interactions between rice and BPH and provide resistance genes and germplasm resources for breeding durable BPH‐resistant rice varieties.
Holmium laser enucleation of the prostate: A truly size‐independent method?
Authors: Tamalunas Alexander , Westhofen Thilo , Schott Melanie , Keller Patrick , Atzler Michael , Stief Christian G. , Magistro Giuseppe
Published: July 2021

Objectives

To evaluate the impact of prostate size on functional outcomes and perioperative morbidity, we analyzed patients undergoing holmium laser enucleation of the prostate (HoLEP) for lower urinary tract symptoms (LUTS). As LUTS secondary to benign prostatic obstruction (BPO) are a chronic progressive disease, prevalence and prostate size increase with age. HoLEP is a size‐independent method for surgical treatment of LUTS/BPO and can be offered in medication‐refractory patients with durable long‐term results and reduced perioperative morbidity.

Methods

We retrospectively collected data of 852 patients who underwent HoLEP for LUTS secondary to BPO between 2014‐2018. Patients were divided into group 1 (≤60 cc), group 2 (>60 < 120 cc), group 3 (≥120 cc). Perioperative parameters, safety and short‐term functional outcomes were assessed and analyzed.

Results

Patients in group 3 were significantly older and showed a significantly higher median prostate‐specific antigen level. Perioperative parameters, such as enucleation time and morcellation time significantly differed in favor of smaller prostate sizes, while enucleation and morcellation speed showed favorable results for larger prostate sizes. Larger prostates ≥120 cc showed a significantly higher postoperative drop in hemoglobin. However, patients did not differ in postoperative functional outcomes or Clavien‐Dindo grade ≥II complications (4.8% of all patients [41/852]). There was no difference in perioperative complications between all groups (P = 0.760).

Conclusion

While larger prostates take significantly longer to operate on, postoperative functional outcomes show no difference between all sizes. In conclusion, HoLEP is a size‐independent and effective method for surgical treatment of LUTS/BPO in prostates ≥30 cc.
Identification and pairing reassessment of unequilibrated ordinary chondrites from four Antarctic dense collection areas
Authors: Righter Kevin , Schutt John , Lunning Nicole , Harvey Ralph , Karner James
Published: July 2021

New analyses of Cr2O3 contents of olivines from type II chondrules in unequilibrated chondrites (UOC) from four dense collections are reported here. This survey of petrologic type 3 UOCs was undertaken to identify primitive chondrites that may have been overlooked, and to address possible pairing errors. We have identified 23 primitive UOCs (≤3.10) (only five identified previously, for a total of 28 overall), and also recommend other revisions to prior classifications and pairings.
Nickel–manganese variability in olivine and Al‐in‐olivine thermometry for olivine‐phyric shergottites
Authors: Ramsey Sierra R. , Howarth Geoffrey H. , Udry Arya , Gross Juliane
Published: July 2021

Olivine‐phyric shergottites represent primitive Martian magmas, but they commonly contain excess olivine and rarely represent primary mantle melts. Olivine chemistry, however, tracks magma evolution and preserves information on the original parent magma composition. Here, we investigate the applicability of the Al‐in‐olivine thermometer in tandem with olivine chemistry in a suite of 13 olivine‐phyric shergottites to constrain the compositions and conditions of their mantle sources and parental magmas. We show that the Al‐in‐olivine thermometer is a robust method for constraining crystallization temperatures in shergottites, yielding temperatures in agreement with experimental work. In contrast, we do not recommend olivine–spinel thermometry relying on Mg‐Fe in olivine, which underestimates crystallization temperatures by 160–380 °C. Olivine chemistry reveals distinct differences in Ni concentrations between shergottite groups, with enriched shergottites generally having higher Ni at a given forsterite (Fo) content. Nickel variations in terrestrial olivine are often accredited to contributions from a pyroxenite source; however, the same mechanism is not responsible for Ni variations in Martian olivine. Here, we favor a model for variable olivine modal abundance, caused by multiple melting episodes in the depleted mantle source, affecting Ni partitioning during melting to account for the Ni variations observed. In addition, we show that olivine Ni‐Mn variations in depleted shergottites indicate variable petrogenetic histories and parental magmas. Tissint contains elevated Ni in olivine more similar to the enriched shergottites whereas DaG 1037 has elevated Mn in olivine suggesting an Mn‐enriched parent magma relative to other depleted shergottites.
Metabolic acidosis in the initial 6 months after renal transplantation: A prospective study
Authors: George Kristin , Upadhyay Ashish Datt , Subbiah Arun Kumar , Yadav Raj Kanwar , Mahajan Sandeep , Bhowmik Dipankar , Agarwal Sanjay Kumar , Bagchi Soumita
Published: July 2021

Background

There is limited information about the incidence of metabolic acidosis (MA) after renal transplantation. This single centre prospective study aimed to delineate the incidence and risk factors of MA in the first 6 months after renal transplantation (RTX).

Design, setting, participants and measurements

Patients who underwent RTX between November 2018 and July 2020 were monitored with weekly measurement of serum bicarbonate level for 6 months and those who were diagnosed with MA were evaluated further to characterize the type of MA.

Results

One hundred and twenty‐five patients were included in the study, 89 (71.2%) of whom developed MA. Seventy‐two patients developed MA in the first month, 11 during the 2–3 months and 6 between 4 and 6 months after transplantation. Of the 89 patients, 55(61.8%) had type 1 renal tubular acidosis (T1RTA), 27 (30.3%) had type 2 RTA (T2RTA) and 7 (7.9%) type 4 RTA (T4RTA). Two patient who had T1RTA, subsequently developed high anion gap MA following severe graft rejection. On stepwise multivariate regression analysis, serum creatinine at time of diagnosis of MA [OR (95% CI): 12.02 (1.79 to 80.59),p = .01] and high tacrolimus C0 levels [OR (95% CI): 2.43 (1.0 to 5.90),p = .049], were independent risk factors for MA.

Conclusion

There is a high incidence of MA in the initial 6 months post‐transplant with serum creatinine and high tacrolimus C0 levels being independent risk factors.
Effect on soil water availability, rather than silicon uptake by plants, explains the beneficial effect of silicon on rice during drought
Authors: Kuhla Jana , Pausch Johanna , Schaller Jörg
Published: July 2021

Various studies showed a decrease of drought stress specific parameters of plants after silicon (Si) fertilization. But all studies differed in soil Si concentration between the control and Si treatments. As amorphous silica (ASi) was recently found to cause a strong increase of water holding capacity and plant available water in soils, a combined effect of soil moisture and plant response due to Si addition was assumed. In this study, the influence of the soil Si content was excluded by using the same Si enriched soil for treatments of two rice lines, lsi1 mutant defective in Si uptake and its wild‐type rice. Most plant parameters, such as nutrient contents, biomass, specific leaf area, specific root length, leaf water content and C allocation did not differ significantly between the genotypes neither under flooded conditions, nor under drought conditions. Only photosynthesis and stomatal conductance were slightly higher for the wild type in both drought and flooded treatments. Overall, our data showed that Si accumulation within the plant tissues has only a minor effect on plant performance under drought stress. Hence, existing studies should be reinterpreted in light of the fact that Si additions may increase soil water availability.
Concomitant BK virus infection and visceral Leishmaniasis in a pediatric liver transplant recipient
Authors: Derakhshan Dorna , Basiratnia Mitra , Derakhshan Ali , Fallahzadeh Mohammad Hossein , Dehghani Seyed Mohsen , Soleimani Neda , Anbardar Mohammad Hossein , Shirazi Yeganeh Babak , Mohammadzadeh Sahand
Published: July 2021

Background

Solid organ transplant recipients are vulnerable to various unusual infections. Visceral Leishmaniasis (VL) is a protozoal opportunistic infection, which may affect the immune‐suppressed hosts and solid organ transplant recipients. The BK virus infection is an evolving challenge in kidney transplant recipients. However, there are very few reports of BK virus (BKV) nephropathy involving the native kidney in liver transplant recipients. To the best of our knowledge, this is the first report of the simultaneous occurrence of these rare infections in a liver transplant recipient.

Case report

The patient was a 9‐year‐old girl, a case of liver transplantation who presented with the incidental finding of proteinuria, azotemia, and cytopenia. Investigations revealed that she had concomitant BKV nephropathy and visceral leishmaniasis. Both infections were successfully treated.

Conclusion

BK virus should be considered as a cause of nephropathy in liver transplant recipients. The presenting features of fever, cytopenia, and splenomegaly in a post‐transplant patient should remind of unusual infections such as VL other than the common post‐transplant conditions.
Inference on the History of a Randomly Growing Tree
Authors: Crane Harry , Xu Min
Published: July 2021

The spread of infectious disease in a human community or the proliferation of fake news on social media can be modelled as a randomly growing tree-shaped graph. The history of the random growth process is often unobserved but contains important information such as the source of the infection. We consider the problem of statistical inference on aspects of the latent history using only a single snapshot of the final tree. Our approach is to apply random labels to the observed unlabelled tree and analyse the resulting distribution of the growth process, conditional on the final outcome. We show that this conditional distribution is tractable under a shape exchangeability condition, which we introduce here, and that this condition is satisfied for many popular models for randomly growing trees such as uniform attachment, linear preferential attachment and uniform attachment on a D-regular tree. For inference of the root under shape exchangeability, we propose O(n log n) time algorithms for constructing confidence sets with valid frequentist coverage as well as bounds on the expected size of the confidence sets. We also provide efficient sampling algorithms which extend our methods to a wide class of inference problems.
Ghazālī's Transformative Answer to Scepticism
Authors: Hadisi Reza
Published: July 2021

Abstract

In this paper, I offer a reconstruction of Ghazālī's encounter with scepticism in the Deliverance from Error. For Ghazālī, I argue, radical scepticism about the possibility of knowledge ensues from intellectualist assumptions about the nature of justification. On the reading that I will propose, Ghazālī holds that foundational knowledge can only be justified via actions that lead to transformative experiences.
When Faced With Increasing Complexity: The Effectiveness of Artificial Intelligence Assistance for Drone Design
Authors: Song Binyang , Soria Zurita Nicolás F. , Nolte Hannah , Singh Harshika , Cagan Jonathan , McComb Christopher
Published: July 2021

As artificial intelligence (AI) assistance tools become more ubiquitous in engineering design, it becomes increasingly necessary to understand the influence of AI assistance on the design process and design effectiveness. Previous work has shown the advantages of incorporating AI design agents to assist human designers. However, the influence of AI assistance on the behavior of designers during the design process is still unknown. This study examines the differences in participants’ design process and effectiveness with and without AI assistance during a complex drone design task using the HyForm design research platform. Data collected from this study are analyzed to assess the design process and effectiveness using quantitative methods, such as hidden Markov models and network analysis. The results indicate that AI assistance is most beneficial when addressing moderately complex objectives but exhibits a reduced advantage in addressing highly complex objectives. During the design process, the individual designers working with AI assistance employ a relatively explorative search strategy, while the individual designers working without AI assistance devote more effort to parameter design.
An Approach for Geometrically Nonlinear Topology Optimization Using Moving Wide-Bézier Components With Constrained Ends
Authors: Zhu Benliang , Wang Rixin , Zhang Hongchuan , Li Hai , Liang Junwen , Zhang Xianmin , Li Hao , Nishiwaki Shinji
Published: July 2021

Standard moving morphable component (MMC)-based topology optimization methods use free components with explicitly geometrical parameters as design units to obtain the optimal structural topology by moving, deforming, and covering such components. In this study, we intend to present a method for geometrically nonlinear explicit topology optimization using moving wide-Bézier components with constrained ends. Not only can the method efficiently avoid the convergence issues associated with nonlinear structural response analysis, but it can also alleviate the component disconnection issues associated with the standard MMC-based topology optimization methods. The numerical investigations proposed in this work indicate that the proposed method allows us to obtain results in accordance with the current literature with a more stable optimization process. In addition, the proposed method can easily achieve minimum length scale control without adding constraints.
Sensitivity Analysis of Schlieren-Particle Image Velocimetry System for Simultaneous Measurement of Flow and Temperature Field of a Free Convective Flow Inside a Cubic Cavity
Authors: Bharti Omprakash S. , Saha Arun K. , Das Malay K.
Published: July 2021

Fluid flows characterized by density variations have been studied using the schlieren-particle image velocimetry (PIV) system. The knife-edge location plays a crucial role in determining the system’s sensitivity, which significantly affects the accuracy of the measured quantities. Further, the optimum knife-edge position and the correct combination of image recording speed and interrogation window size are desirable for achieving the most accurate and reliable results. The present paper discusses the above issues on the measured quantities, such as temperature field, local Nusselt number distribution along the conducting walls, average Nusselt number, and velocity field. The experiment is performed to investigate laminar and steady natural convective flow in a water-enclosed cubic cavity with a left hot wall and a right cold wall. The analysis is undertaken for various knife-edge positions (0–90%), different image time separation varying (20–200 ms,) and interrogation window size using two passes varying from W1 = 32 pixels, W2 = 16 pixels to W1 = 128 pixels, W2 = 64 pixels. The results are presented for two distinct Rayleigh number, 1 × 108 and 3 × 108. Three-dimensional simulations have been carried out to check the fidelity of the experiment for Ra = 1 × 108. A high dynamic range of temperature is obtained for the range of knife-edge position in 50–65% while a high-velocity range is realized for knife-edge cutoff of 65% and combination of image time separation of Δt = 100 ms and interrogation window size with two passes of W1 = 64 pixels followed by W2 = 32 pixels.
Theoretical and Experimental Study of the Effect of Mini Channel Finned Heatsink on Thermoelectric Generator Performance in Air-Cooled Environment
Authors: Huang Shenghui , Li Wenbin , Xu Daochun , Sui Xiaomei , Zhang Yuqi
Published: July 2021

Air-cooled finned heatsink (FHS) are more compact than water-cooled heatsink due to no water channel, which is beneficial to simplify the structure of the cooling side of the thermoelectric generator (TEG) system. Therefore, a mini channel finned heatsink (MCFHS) was designed in this study based on Venturi effect. In this study, the mathematical model of TEG with MCFHS and FHS were developed and verified. The effects of the heating temperature and air flow velocity around the heatsinks on the TEG performance were analyzed and demonstrated. The TEG performance was investigated in terms of the temperatures of the two sides of the TEG, the TEG voltage, and the TEG efficiency. The results revealed that the smaller thermal resistance of heatsink is favorable for greater output of TEG. And the use of the MCFHS can effectively improve the performance of the TEG under different conditions. The maximum TEG efficiency with MCFHS could be 155% higher than the TEG with FHS.
Short Term Photovoltaic Power Forecasting
Authors: Elsherbiny Lamiaa , Al-Alili Ali , Alhassan Saeed
Published: July 2021

Due to the rapid increase of energy demand and the continuous decrease of renewable energy cost, photovoltaic (PV) installed capacity has increased significantly. The PV power output depends on the available solar irradiance and other meteorological data such as air temperature, wind speed, and relative humidity. The performance of PV panels also depends on the cleaning frequency and maintenance of these panels. Soiling is considered to be a key factor on PV performance in desert areas. The Middle East has one of the highest dust intensity in the world which results in dramatic PV power losses. Therefore, forecasting the power output of PV panels is essential for the development of smart grids and smart metering techniques. In this study, a hybrid Artificial Neural Network (ANN) is developed to forecast the performance of a PV panel. The hybrid ANN is trained on the local weather and solar data as well as different cleaning frequencies. Then, the performance of the hybrid-ANN is compared to that of a conventional ANN. The results are presented in terms of different statistical indices such as the root mean square error (RMSE) and the mean bias error (MBE). The results are used to find the optimal cleaning frequency required for the optimal PV performance.
Optimal Design of Novel Laminated Cooling System Considering Cooling Effectiveness and Thermomechanical Performance
Authors: Li Honglin , Li Lei , Gao Wenjing , Tang Zhonghao , Tan Chunlong , Ren Shuoshuo
Published: July 2021

Laminated cooling is deemed as one of the most potential and novel cooling technologies for turbine blade to increase turbine inlet temperature, which combines the superiority of film cooling, pin fin cooling and impingement cooling. To realize optimal design, the multidisciplinary design optimization of laminated cooling configuration is conducted considering cooling performance under acceptable pressure loss and thermomechanical performance. A coupled multidisciplinary analysis model is established to perform aerodynamical analysis, heat transfer analysis and thermomechanical analysis. Based on parametrized laminated model and Design of Experiments method, the cooling effectiveness, pressure loss coefficient and maximum stress can be obtained under different design parameters and their dominated design variables can be clarified. Using these sampling points, a Kriging approximation surrogate model can be established to replace real numerical calculation process and balance the efficiency and fidelity. Finally, the multi-island genetic algorithm is used to find the maximum cooling effectiveness and minimum pressure loss under the constraint of maximum stress. Results shows that, the dilation of film hole diameter, pin fin diameter and impingement hole diameter and the reduction of target plate thickness can effectively improve cooling performance and meanwhile decrease maximum stress, which can be up to 17.68% and 4.96% separately under the acceptable poressure loss coefficient raise of 16.8%. That can be attributed to the enhancement of inner heat transfer and improvement of outer film cooling.
Investigation of Buoyancy Effects in Asymmetrically Heated Near-Critical Flows of Carbon Dioxide in Horizontal Microchannels Using Infrared Thermography
Authors: Randle Lindsey V. , Fronk Brian M.
Published: July 2021

In this study, we use infrared thermography to calculate local heat transfer coefficients of top and bottom heated flows of near-critical carbon dioxide in an array of parallel microchannels. These data are used to evaluate the relative importance of buoyancy for different flow arrangements. A Joule heated thin wall made of Inconel 718 applies a uniform heat flux either above or below the horizontal flow. A Torlon PAI test section consists of three parallel microchannels with a hydraulic diameter of 923 μm. The reduced inlet temperature (TR = 1.006) and reduced pressure (PR = 1.03) are held constant. For each heater orientation, the mass flux (520 kgm−2s−2 ≤ G ≤ 800 kgm−2s−2) and heat flux (4.7 Wcm−2 ≤ q″ ≤ 11.1 Wcm−2) are varied. A 2D resistance network analysis method calculates the bulk temperatures and heat transfer coefficients. In this analysis, we divide the test section into approximately 250 segments along the stream-wise direction. We then calculate the bulk temperatures using the enthalpy from the upstream segment, the heat flux in a segment, and the pressure. To isolate the effect of buoyancy, we screen the data to omit conditions where flow acceleration may be important or where relaminarization may occur. In the developed region of the channel, there was a 10 to 15 percent reduction of the local heat transfer coefficients for the upward heating mode compared to downward heating with the same mass and heat fluxes. Thus buoyancy effects should be considered when developing correlations for these types of flow.
Slip Gas Flow and Heat Transfer in Confined Porous Media With Different Shape Cylinders
Authors: Tariq Ammar , Liu Zhenyu
Published: July 2021

With the recent advances in micro devices, an accurate gas flow and heat transfer analysis become more relevant considering the slip effect. A micro-scale, multiple-relaxation-time (MRT) lattice Boltzmann method with double distribution function approach is used to simulate flow and heat transfer through circular- and diamond-shaped cylinders at the porescale level. The velocity slip and temperature jump are captured at the boundaries using a non-equilibrium extrapolation scheme with the counter-extrapolation method. A pore-scale domain of micro-cylinders comprised of circle and diamond shape are studied. It is found that the permeability increases linearly with an increase in Knudsen number for both circular- and diamond-shaped cylinders. However, the permeability increase for circular obstacle is larger than that of the diamond one. A larger surface area for diamond cylinder will offer more resistance to flow, hence resulting in lower values. For heat transfer, the Nusselt number shows an increase with increasing Reynolds number, however, it decreases with the increase in porosity. Nusselt number values are found to be higher for a circular obstacle. A variable boundary gradient for circular obstacle could be a possible explanation for this difference.
Numerical Simulation of Indoor Human Sneezing
Authors: Janajreh Isam , Sajjad Muhammad , Islam MD. , Janajreh Lina
Published: July 2021

Transient numerical simulations have been carried out to mimic and analyse the transmission of various species resulting from human sneezing. The extent of the spread of sneezed air and associated droplets is also investigated based on various parameters. A 2D geometry of the human face is considered that captures the true topology and the outlet characteristics of the exhaled air mixture. Numerous parameters are required to be considered to capture the out-coming mixture trajectory and to track its concentration evolution as it enters and entrains with the surrounding air. These parameters include the velocity of the exhaled air mixture, the extent of mouth opening, the distribution of the mixture fraction, and its mist content. A multi-species Eulerian flow with discrete phase Lagrangian particles is considered. The results include the spatial and temporal distributions of the species and their velocity contour plots. Specifically, the concentration of the exhaled species is captured both spatially and temporally at several hypothetical stations within the computational domain, and away from the source to substantiate/refute the current recommended social distance parameter.
Testosterone and socioeconomic position: Mendelian randomization in 306,248 men and women in UK Biobank
Authors: Harrison Sean , Davies Neil M. , Howe Laura D. , Hughes Amanda
Published: July 2021

Mendelian randomization suggests circulating testosterone does not meaningfully affect men’s socioeconomic position.
Disassembly of HIV envelope glycoprotein trimer immunogens is driven by antibodies elicited via immunization
Authors: Turner Hannah L. , Andrabi Raiees , Cottrell Christopher A. , Richey Sara T. , Song Ge , Callaghan Sean , Anzanello Fabio , Moyer Tyson J. , Abraham Wuhbet , Melo Mariane , Silva Murillo , Scaringi Nicole , Rakasz Eva G. , Sattentau Quentin J. , Irvine Darrell J. , Burton Dennis R. , Ward Andrew B.
Published: July 2021

HIV Env trimers elicit antibodies that lead to their own destruction.
An Infectious Rous Sarcoma Virus Gag Mutant That Is Defective in Nuclear Cycling
Authors: Ricaña Clifton L. , Johnson Marc C.
Published: July 2021

While mechanisms for retroviral Gag assembly at the plasma membrane are beginning to be characterized, characterization of intermediate trafficking locales remain elusive. This is in part due to the difficulty of tracking individual proteins from translation to plasma membrane binding.
BbWor1, a Regulator of Morphological Transition, Is Involved in Conidium-Hypha Switching, Blastospore Propagation, and Virulence in Beauveria bassiana
Authors: Qiu Lei , Zhang Tong-Sheng , Song Ji-Zheng , Zhang Jing , Li Ze , Wang Juan-Juan
Published: July 2021

As a well-known entomopathogenic fungus,
Beauveria bassiana
has a complex life cycle and involves transformations among single-cell conidia, blastospores, and filamentous hyphae. This study provides new insight into the regulation of the fungal cell morphological transitions by simulating three models.
Coaches’ attitudes to injury and injury prevention: a qualitative study of Irish field hockey coaches
Authors: Rees Huw , Matthews James , McCarthy Persson Ulrik , Delahunt Eamonn , Boreham Colin , Blake Catherine
Published: July 2021

Translating injury prevention research into practice has been challenging, which may be due to a poor understanding of the contextual factors influencing the occurrence of injury. Coaches are key figure in sporting environments and hold pivotal roles in preventing injury. Therefore, the aim of this study was to investigate the attitudes of field hockey coaches to injury and injury prevention. Thirteen field hockey coaches from the amateur Irish Hockey League were interviewed. Reflexive thematic analysis led to three general dimensions comprised five higher-order themes, categorised from 16 lower-order themes. Coaches had positive beliefs regarding the benefits of injury prevention over injury management. However, they lacked the necessary knowledge and skills to successfully implement injury prevention strategies with players. Coaches recognised the importance of empowering players to self-manage training loads to promote injury prevention but acknowledged the need to protect younger players from increased loads. Many barriers to injury prevention were not controllable by coaches including fixture congestion and poor structuring of the sport’s domestic calendar. While coaches can play a key role in the implementation of injury prevention strategies, there is also a requirement to examine how system level barriers to injury prevention can be reduced.
The Canadian Beaufort Shelf trophic structure: evaluating an ecosystem modelling approach by comparison with observed stable isotopic structure
Authors: Hoover C. , Giraldo C. , Ehrman A. , Suchy K.D. , MacPhee S.A. , Brewster J. , Reist J.D. , Power M. , Swanson H. , Loseto L.
Published: July 2021

Climate-driven impacts on marine trophic pathways worldwide are compounded by sea-ice loss at northern latitudes. For the Arctic, current information describing food-web linkages is fragmented, and there is a need for tools that can describe overarching trophic structure despite limited species-specific data. Here, we tested the ability of a mass-balanced ecosystem model (Ecopath with Ecosim, EwE) to reconstruct the trophic hierarchy of 31 groups, from primary producers to polar bears, in the Canadian Beaufort Sea continental shelf. Trophic level (TL) estimates from EwE were compared with those derived from two nitrogen stable isotope (SI) modelling approaches (SI linear and scaled) to assess EwE accuracy, using a data set of 642 δ15N observations across 282 taxa. TLs from EwE were strongly, positively related to those from both SI models (R2 > 0.80). EwE performed well (within 0.2 TL) for groups with relatively well-known diets or for taxa characterized by fewer trophic connections (e.g., primary consumers). Performance was worse (>0.5 TL) for species groups aggregated at coarse taxonomic levels, those with poorly documented diets, and for anadromous fishes. Comparisons with SI models suggested that the scaled approach can overestimate the TL of top predators if ecosystem-specific information is not considered.
Performance Evaluation of AODV and DSR Routing Protocols for Flying Ad hoc Network Using Highway Mobility Model
Authors: Maakar Sunil Kr , Khurana Manju , Chakraborty Chinmay , Sinwar Deepak , Srivastava Durgesh
Published: July 2021

The Flying Ad hoc Network (FANET) is a special type of mobile ad hoc network (MANET) that provides communications among Unmanned Aerial Vehicles (UAVs). These UAVs can reduce human intervention to a great extent by giving numerous applications under different domains such as transportation, military, healthcare, traffic monitoring, surveillance, etc. In FANET, communication is relatively challenging due to its complex infrastructure, unspecified architecture and rapid mobility of nodes. The work embodied in this paper is focused on traffic surveillance of highways using UAVs. UAVs can help to reduce the number of accidents by sharing real-time as well as the accurate status of highways among vehicles and the control station. On the other hand, they can also be used to track specific vehicles on the road. In FANET, both routing protocols and mobility models play a crucial role in the process of information exchange. In this paper, the comparison and performance evaluation of two well-known reactive routing protocols viz. Ad hoc On-demand Distance Vector (AODV) and Dynamic Source Routing (DSR) have been carried out using highway mobility model for traffic surveillance in FANET environment. Implementation of both protocols has been tested on several traffic patterns, mobility and varying network loads. Both AODV and DSR enable significant performance variations; however, they share on-demand behavior. Packet delivery fraction, average end-to-end delay, normalized routing load, packet loss, routing overhead and throughput are used to analyze the performance of both protocols. Based on experimental analysis using NS-2 under constant bit rate (CBR) and TCP traffic sources, it can be stated that AODV outperforms DSR in almost every aspect.