bluuebunny/crossref_metadata_2025 huggingface dataset:
The influence of stochasticity, landscape structure and species traits on abundant–centre relationships
Authors: Dallas Tad A. , Santini Luca
Published: June 2020

Species have been commonly hypothesized to have high population densities in geographic areas which correspond to either the centre of the species geographic range or climatic niche (abundant–centre hypothesis). However, there is mixed empirical support for this relationship, and little theoretical underpinning. We simulate a species spreading across a set of replicated artificial landscapes to examine the expected level of support for abundant–centre relationships in geographic and niche space. Species niche constraints were modeled as a single axis which was related directly to population growth rates. We found strong evidence for abundant–centre relationships when populations follow deterministic growth, dispersal is high, environmental noise is absent and intraspecific competition is low. However, the incorporation of ecological realism reduced the detectability of abundant–centre relationships considerably. Our results suggest that even in carefully constructed artificial landscapes designed to demonstrate abundant–centre dynamics, the incorporation of small amounts of demographic stochasticity, environmental heterogeneity or landscape structure can strongly influence the relationship between species population density and distance to species geographic range or niche centre. While some simulated relationships were of comparable strength to common empirical support for abundant–centre relationships, our results suggest that these relationships are expected to be fairly variable and weak.
Spatial organisation of fish assemblages in the Chishui River, the last free‐flowing tributary of the upper Yangtze River, China
Authors: Liu Fei , Wang Jun , Zhang Fu‐Bin , Liu Huan‐Zhang , Wang Jian‐Wei
Published: June 2020

The Chishui River is the last free‐flowing tributary of the upper Yangtze River, China, which has an important role in fish conservation. This study aimed to explore the spatial organisation of fish assemblages in this river. Field sampling was conducted biannually between 2015 and 2017 at 41 sites from its headwater and downstream. One hundred and twenty‐two fish species were captured, including 34 endemic, 15 threatened and six exotic species. Fish assemblages varied significantly along the longitudinal gradient. Based on cluster and ordination analyses, 41 sampling sites could be divided into five site‐groups, corresponding to the headwater, upstream, midstream, downstream and the Xishui‐branch, respectively. The splitting of fish assemblages was consistent with the geographical divisions. However, fish species changed gradually along the longitudinal gradient rather than abruptly, which was consistent with the River Continuum Concept (RCC). In the headwaters and upstream, fish assemblages were mainly dominated by cold‐water and rheophilic species, while in the lower stretches, fish assemblages were dominated by warm‐water and limnophilic species. According to null models, fish assemblages were significantly nonrandomly structured at the basin scale, but randomly structured at the regional scale. This study is an important step in understanding the assembly rules of fish assemblages in this free‐flowing river and provides useful information for future fish conservation and ecological restoration.
Evolutionary responses of marine organisms to urbanized seascapes
Authors: Elizabeth Alter S. , Tariq Laraib , Creed James Keanu , Megafu Emmanuel
Published: June 2020

Many of the world's major cities are located in coastal zones, resulting in urban and industrial impacts on adjacent marine ecosystems. These pressures, which include pollutants, sewage, runoff and debris, temperature increases, hardened shorelines/structures, and light and acoustic pollution, have resulted in new evolutionary landscapes for coastal marine organisms. Marine environmental changes influenced by urbanization may create new selective regimes or may influence neutral evolution via impacts on gene flow or partitioning of genetic diversity across seascapes. While some urban selective pressures, such as hardened surfaces, are similar to those experienced by terrestrial species, others, such as oxidative stress, are specific to aquatic environments. Moreover, spatial and temporal scales of evolutionary responses may differ in the ocean due to the spatial extent of selective pressures and greater capacity for dispersal/gene flow. Here, we present a conceptual framework and synthesis of current research on evolutionary responses of marine organisms to urban pressures. We review urban impacts on genetic diversity and gene flow and examine evidence that marine species are adapting, or are predicted to adapt, to urbanization over rapid evolutionary time frames. Our findings indicate that in the majority of studies, urban stressors are correlated with reduced genetic diversity. Genetic structure is often increased in urbanized settings, but artificial structures can also act as stepping stones for some hard‐surface specialists, promoting range expansion. Most evidence for rapid adaptation to urban stressors comes from studies of heritable tolerance to pollutants in a relatively small number of species; however, the majority of marine ecotoxicology studies do not test directly for heritability. Finally, we highlight current gaps in our understanding of evolutionary processes in marine urban environments and present a framework for future research to address these gaps.
Systemic chemotherapy promotes HIF‐1α‐mediated glycolysis and IL‐17F pathways in cutaneous T‐cell lymphoma
Authors: Wang Bo , Li Kejia , Wang Honglin , Shen Xiaoyan , Zheng Jie
Published: June 2020

Background

Systemic chemotherapy is often the last resort of advanced cutaneous T‐cell lymphoma (CTCL). Tumor recurrence and adverse effects of systemic chemotherapy are the main limitations.

Objective

We aim to investigate the metabolic alterations in tumor cells after CHOP (cyclophosphamide, hydroxydaunorubicin, oncovin and prednisone) chemotherapy.

Methods and Results

In advanced CTCL, CHOP chemotherapy has no survival benefit and the duration of response is significantly inferior to other canonical treatments. HIF‐1α is significantly elevated in lesions of advanced MF patients as well as tumor cell line Hut78 and tumor xenograft mice model. CHOP therapy also increased glycolytic activities in a HIF‐1α‐dependent manner. In CTCL xenograft tumor mice model, lesional cells showed a significant increase in IL‐17F after chemotherapy, shifting toward a Th17 phenotype, which process is also regulated by HIF‐1α. Echinomycin, HIF‐1α inhibitor, was co‐administered in xenograft tumor mouse models with CHOP and showed a significant reduction in tumor growth.

Conclusion

CHOP chemotherapy promotes glycolysis and IL‐17 pathways in a HIF‐1α‐dependent fashion. Furthermore, HIF‐1α blockade is promising as an accompanying agent in systemic chemotherapy for patients with advanced CTCL.
Increasing light physical activity helps to maintain cognitive function among the community‐dwelling oldest old population: a cross‐sectional study using actigraph from the Arakawa 85+ study
Authors: Suzuki Kouta , Niimura Hidehito , Kida Hisashi , Eguchi Yoko , Kitashima Chiho , Takayama Midori , Mimura Masaru
Published: June 2020

Aim

To investigate the influence of replacing sedentary time with physical activity on cognitive function using an isotemporal substitution model in a population of community‐dwelling oldest old.

Methods

This cross‐sectional study included residents of the Arakawa ward, Tokyo, who were part of a prospective cohort from the Arakawa 85+ study. We measured physical activity in 136 participants using a triaxial actigraph. Cognitive function was measured using the Addenbrooke's Cognitive Examination‐III and participants were divided into a “cognitive decline group” (Addenbrooke's Cognitive Examination‐III ≤88) and “cognitive maintain group” (Addenbrooke's Cognitive Examination‐III ≥89). Physical activity was divided into three categories: sedentary behavior (≤1.5 metabolic equivalents), light physical activity (>1.5 to <3.0 metabolic equivalents), and moderate‐to‐vigorous physical activity (≥3 metabolic equivalents). Using an isotemporal substitution approach, we applied multiple logistic regression analysis to demonstrate the association between cognitive function and replacing 30 min/day of sedentary behavior with an equal period of light physical activity. Covariates included age, education and the Center for Epidemiologic Studies Depression Scale.

Results

Our findings showed that in men, replacing 30 min of sedentary behavior per day with light physical activity was associated with a 1.47‐fold increase in the odds of maintaining cognitive function. An association between physical activity and cognitive function was not observed in female participants.

Conclusions

Our results indicate that substituting sedentary behavior with light physical activity could be helpful in maintaining cognitive function in community‐dwelling oldest old men. These results highlight the importance of behavioral changes to promote cognition. Geriatr Gerontol Int 2020; 20: 773–778.
Academic motherhood during COVID‐19: Navigating our dual roles as educators and mothers
Authors: Guy Batsheva , Arthur Brittany
Published: June 2020

During the COVID‐19 crisis, being a working mother has taken on a whole new meaning, as mothers navigate working from home while juggling childcare, as well as coming to terms with their intersecting identities. The current article is a feminist, heartful autoethnographic account, couched in Relational‐Cultural Theory, surrounding our authentic experiences working from home and raising children during the worldwide pandemic. We explore academic motherhood, working from home, mental health, and coping during coronavirus and stay‐at‐home orders through engaged dialogue. We hope that showcasing our vulnerability can lead to change in the expectations we put on mothers in academia, while at the same time connect with readers who may be going through similar challenges.
Marketing strategy selection of referral reward under social network: RRWS, RRMS, or dual strategy?
Authors: Gao Mei , Zhao Meng , Qin Jinlei
Published: June 2020

With the arrival of the social media era and the fragmentation of consumer habits, how to develop the optimal marketing strategy for products has become a hot topic. When a consumer purchases a product, the firm provides a link for him/her to share with friends, and doing so can expand demand and increase profits. This paper considers three strategies: the referral reward strategy that does not care whether successful, the referral reward strategy that must be successful, and the dual strategy. To provide firms with advice, this paper adopts literature analysis and survey analysis to examine the three strategies of operation mode, and uses backward induction and optimization method to solve the optimal pricing. Finally, the influence of different network structures on strategy selection is studied by numerical simulation experiments. Results show that the strategy of referral reward under social network is feasible and profitable when the firm faces serious information problems and the reward cost is low. Compared with the basic model without bonuses, the introduction of rewards reduces the price of first‐period consumers and affects their motivation to share information. Among the three strategies, the distribution ratio of the unit bonus has little effect on profit. The second‐period price and profits of the dual strategy are higher than those of the two other strategies. Besides, the structure of social networks has a small impact on profits, so adopting the dual strategy can obtain higher profit than adopting either of the other two strategies.
Sitagliptin improves functional recovery via GLP‐1R‐induced anti‐apoptosis and facilitation of axonal regeneration after spinal cord injury
Authors: Han Wen , Li Yao , Cheng Jiangting , Zhang Jing , Chen Dingwen , Fang Mingqiao , Xiang Guangheng , Wu Yanqing , Zhang Hongyu , Xu Ke , Wang Hangxiang , Xie Ling , Xiao Jian
Published: June 2020

Axon growth and neuronal apoptosis are considered to be crucial therapeutic targets against spinal cord injury (SCI). Growing evidences have reported stimulation of glucagon‐like peptide‐1 (GLP‐1)/GLP‐1 receptor (GLP‐1R) signalling axis provides neuroprotection in experimental models of neurodegeneration disease. Endogenous GLP‐1 is rapidly degraded by dipeptidyl peptidase‐IV (DPP4), resulting in blocking of GLP‐1/GLP1R signalling process. Sitagliptin, a highly selective inhibitor of DPP4, has approved to have beneficial effects on diseases in which neurons damaged. However, the roles and the underlying mechanisms of sitagliptin in SCI repairing remain unclear. In this study, we used a rat model of SCI and PC12 cells/primary cortical neurons to explore the mechanism of sitagliptin underlying SCI recovery. We discovered the expression of GLP‐1R decreased in the SCI model. Administration of sitagliptin significantly increased GLP‐1R protein level, alleviated neuronal apoptosis, enhanced axon regeneration and improved functional recovery following SCI. Nevertheless, treatment with exendin9‐39, a GLP‐1R inhibitor, remarkably reversed the protective effect of sitagliptin. Additionally, we detected the AMPK/PGC‐1α signalling pathway was activated by sitagliptin stimulating GLP‐1R. Taken together, sitagliptin may be a potential agent for axon regrowth and locomotor functional repair via GLP‐1R‐induced AMPK/ PGC‐1α signalling pathway after SCI.
A sugar‐coated strategy to treat a rare neurologic disease provides a blueprint for a decoy glycan therapeutic and a potential vaccine for CoViD‐19
Authors: Steinman Lawrence
Published: June 2020

In a rare neurologic disease known as IgM monoclonal gammopathy the immune system targets a sulfated trisaccharide known as the Human Natural Killer‐1 (HNK‐1) epitope that comprises a constituent of the myelin sheath known as MAG (myelin‐associated glycoprotein). This Editorial highlights a study by Aliu and colleagues in the current issue of the Journal of Neurochemistry, in which the investigators constructed a biodegradable poly‐l‐lysine backbone with multiple copies of this sulfated HNK‐1 trisaccharide. This decoy, poly(phenyl disodium 3‐O‐sulfo‐β‐d‐glucopyranuronate)‐(1→3)‐β‐d‐galactopyranoside, known as PPSGG, removed anti‐MAG IgM autoantibodies from the blood, while not activating the immune system. These findings provide a path for the selective removal of a pathogenic set of antibodies that target the myelin sheath resulting in neuropathy. These findings are applicable to a parallel strategy for the generation of polysaccharides similar to those present in the receptor‐binding domain of CoViD‐19, which might inhibit viral adhesion to its receptor, the angiotensin‐converting enzyme‐2 (ACE2) protein, thereby impairing cellular uptake of the virus itself. The deployment of complex polysaccharides that mimic actual COVID19 polysaccharides on the spike protein may also provide a feasible structural basis for a vaccine. Carbohydrate mimics, if conjugated to a carrier or backbone, might provoke an immune response to the spike protein. A vaccine that targets critical carbohydrates on COVID19, and then neutralizes the virus would recapitulate a successful strategy employed in other microbial vaccines, like the pneumococcal vaccines and the meningococcal vaccines. These vaccines direct an immune response to complex carbohydrates and successfully prevent life‐threatening disease. This paper provides lessons from a rare neurologic disease that may teach us strategies applicable to a global pandemic.

image
Effect of oxybrasion on selected skin parameters
Authors: Jarząbek Sylwia , Rotsztejn Helena
Published: June 2020

Background

Oxybrasion is one of the types of microdermabrasion. This method removes a superficial epidermal layer with the use of a stream of 0.9% saline solution and compressed air.

Aims

The assessment of skin hydration, sebum, pH, TEWL (transepidermal water loss), and pigmentation using oxybrasion.

Material and methods

The study involved 27 female subjects. Five treatments were performed every 2 weeks using the oxygen microdermabrasion. Measurements of the skin parameters were taken before each treatment and 2 weeks after the last procedure. The measurement points were on the forehead, the cheek, and on the petal of the nose.

Results

Sebum measurement showed some statistically significant differences between the sebum level on the cheek and the nose after a series of treatments. A higher hydration level was found at all measurement points. There were no statistically significant differences in TEWL parameter. pH measurement showed that the pH value decreased after each of the procedures. Most of the pigmentation measurements differed in a statistically significant way.

Conclusion

Results of the study indicate that the oxybrasion treatments increase the skin hydration and they have a significant influence on the decrease of the skin hydrolipid coat and pH.
Coeliac disease and noncoeliac wheat or gluten sensitivity
Authors: Rej A. , Aziz I. , Sanders D.S.
Published: June 2020

Coeliac disease (CD) and noncoeliac wheat or gluten sensitivity (NCWS/NCGS) are common gluten‐related disorders. Both conditions can present with gastrointestinal and extraintestinal manifestations, which can be a challenge for physicians to discern between. Whilst coeliac serology and histological assessment are required for the diagnosis of CD, there are no clear biomarkers for the diagnosis of NCGS. The management of both conditions is with a gluten‐free diet (GFD), although the duration, as well as strictness of adherence to a GFD in NCGS, is unclear. Adherence to a GFD in CD can also be challenging, with recent developments of noninvasive assessments, although histological assessment via duodenal biopsies remains the gold standard. The management of refractory coeliac disease remains particularly challenging, often requiring specialist input. Whilst wheat is noted to be a trigger for symptom generation in NCGS, it is unclear which components of wheat are responsible for symptom generation in this group, with further research required to elucidate the pathophysiology.
Continuous‐time mean–variance portfolio selection: A reinforcement learning framework
Authors: Wang Haoran , Zhou Xun Yu
Published: June 2020

We approach the continuous‐time mean–variance portfolio selection with reinforcement learning (RL). The problem is to achieve the best trade‐off between exploration and exploitation, and is formulated as an entropy‐regularized, relaxed stochastic control problem. We prove that the optimal feedback policy for this problem must be Gaussian, with time‐decaying variance. We then prove a policy improvement theorem, based on which we devise an implementable RL algorithm. We find that our algorithm and its variant outperform both traditional and deep neural network based algorithms in our simulation and empirical studies.
X‐ray computed tomography: Morphological and porosity characterization of giant Antarctic micrometeorites
Authors: Dionnet Zelia , Suttle Martin D. , Longobardo Andrea , Rotundi Alessandra , Folco Luigi , Della Corte Vincenzo , King Andrew
Published: June 2020

Giant micrometeorites (MMs; 400–2000 µm) are exceedingly rare and scientifically valuable. Three‐dimensional nondestructive characterization by X‐ray computed tomography (X‐CT) provides information on the petrography and thus petrogenesis of MMs and serves as a guide to maximize subsequent multi‐analytical studies on such precious planetary materials. Here, we discuss the results obtained by X‐CT on 22 giant MMs and the classification based on their 3‐D density contrast images. Scoriaceous and unmelted MMs have distinct porosity ranges (10–40 vol% versus 0–25 vol%, respectively). We observe a porosity variation inside scoriaceous MMs, which allows their atmospheric entry flight history to be resolved. For the first time, spinning entry is explicitly demonstrated for four partially melted MMs. Furthermore, we are able to resolve the thermal gradient in a single particle, based on porosity variation (seen as a progressive increase in pore abundance and size with higher peak temperatures). Moreover, we explore parent body alteration through the 3‐D analysis of pores distribution, showing that shock fabrics are either absent or weakly developed in our data set. Finally, owing to the detection of pseudomorphic chondrules, we estimate that the intensively aqueously altered C1 or CI‐like material could represent 18% of the MM flux at this size fraction (400–1000 µm).
Going Beyond Mathematics Anxiety in Primary and Middle School Students: The Role of Ego‐Resiliency in Mathematics
Authors: Donolato Enrica , Toffalini Enrico , Giofrè David , Caviola Sara , Mammarella Irene C.
Published: June 2020

Previous research examined the influence of math anxiety (MA) on performance in mathematics, but few studies compared the contribution of MA to other forms of anxiety, such as test and general anxiety (GA). Unlike MA, ego‐resiliency promotes the management of challenges, and has been positively associated with mathematics performance. In this study, we investigated the specific influence of MA, test‐ and GA, and ego‐resiliency on mathematics performance after controlling for intelligence. Children from grades 5 to 8 (N = 274) were assessed with self‐report tools measuring MA, test and GA, and ego‐resiliency, and completed intelligence and mathematical tasks. The results of structural equation models showed that MA had a main negative effect on mathematics performance, over and above the effect of test‐ and GA. Ego‐resiliency had a positive effect on mathematics performance, and was negatively associated with GA. Our findings are discussed in terms of the implications for intervention programs to reduce anxiety and sustain ego‐resiliency.
Hurricanes overcome migration lag and shape intraspecific genetic variation beyond a poleward mangrove range limit
Authors: Kennedy John Paul , Dangremond Emily M. , Hayes Matthew A. , Preziosi Richard F. , Rowntree Jennifer K. , Feller Ilka C.
Published: June 2020

Expansion of many tree species lags behind climate change projections. Extreme storms can rapidly overcome this lag, especially for coastal species, but how will storm‐driven expansion shape intraspecific genetic variation? Do storms provide recruits only from the nearest sources, or from more distant sources? Answers to these questions have ecological and evolutionary implications, but empirical evidence is absent from the literature. In 2017, Hurricane Irma provided an opportunity to address this knowledge gap at the northern range limit of the neotropical black mangrove (Avicennia germinans) on the Atlantic coast of Florida, USA. We observed massive post‐hurricane increases in beach‐stranded A. germinans propagules at, and past, this species’ present day range margin when compared to a previously surveyed nonhurricane year. Yet, propagule dispersal does not guarantee subsequent establishment and reproductive success (i.e., effective dispersal). We also evaluated prior effective dispersal along this coastline with isolated A. germinans trees identified beyond the most northern established population. We used 12 nuclear microsatellite loci to genotype 896 hurricane‐driven drift propagules from nine sites and 10 isolated trees from four sites, determined their sources of origin, and estimated dispersal distances. Almost all drift propagules and all isolated trees came from the nearest sources. This research suggests that hurricanes are a prerequisite for poleward range expansion of a coastal tree species and that storms can shape the expanding gene pool by providing almost exclusively range‐margin genotypes. These insights and empirical estimates of hurricane‐driven dispersal distances should improve our ability to forecast distributional shifts of coastal species.
Population genetic structure and demographic history of the lone star tick, Amblyomma americanum (Ixodida: Ixodidae): New evidence supporting old records
Authors: Lado Paula , Smith Megan L. , Carstens Bryan C. , Klompen Hans
Published: June 2020

Range expansions are a potential outcome of changes in habitat suitability, which commonly result as a consequence of climate change. Hypotheses on such changes in the geographic distribution of a certain species can be evaluated using population genetic structure and demography. In this study we explore the population genetic structure, genetic variability, demographic history of, and habitat suitability for Amblyomma americanum, a North American tick species that is a known vector of several pathogenic microorganisms. We used a double digestion restriction site‐associated DNA sequencing technique (dd‐RAD seq) and discovered 8,181 independent single nucleotide polymorphisms (SNPs) in 189 ticks from across the geographic range of the species. Genetic diversity was low, particularly when considering the broad geographic range of this species. The edge populations were less diverse than populations belonging to the historic range, possibly indicative of a range expansion, but this hypothesis was not statistically supported by a test based on genetic data. Nonetheless, moderate levels of population structure and substructure were detected between geographic regions. For New England, demographic and species distribution models support a scenario where A. americanum was present in more northern locations in the past, underwent a bottleneck, and subsequently recovered. These results are consistent with a hypothesis that this species is re‐establishing in this area, rather than one focused on range expansion from the south. This hypothesis is consistent with old records describing the presence of A. americanum in the northeastern US in the early colonial period.
Uncertainty‐assisted deep vision structural health monitoring
Authors: Sajedi Seyed Omid , Liang Xiao
Published: June 2020

Computer vision leveraging deep learning has achieved significant success in the last decade. Despite the promising performance of the existing deep vision inspection models, the extent of models’ reliability remains unknown. Structural health monitoring (SHM) is a crucial task for the safety and sustainability of structures, and thus, prediction mistakes can have fatal outcomes. In this paper, we use Bayesian inference for deep vision SHM models where uncertainty can be quantified using the Monte Carlo dropout sampling. Three independent case studies for cracks, local damage identification, and bridge component detection are investigated using Bayesian inference. Aside from better prediction results, the two uncertainty metrics, variations in softmax probability and entropy, are shown to have good correlations with misclassifications. However, modifying the decision or triggering human intervention can be challenging based on raw uncertainty outputs. Therefore, the concept of surrogate models is proposed to develop the models for uncertainty‐assisted segmentation and prediction quality tagging. The former refines the segmentation mask and the latter is used to trigger human interventions. The proposed framework can be applied to future deep vision SHM frameworks to incorporate model uncertainty in the inspection processes.
Assessment of adherence to asthma controllers in children and adolescents
Authors: Marckmann Mads , Hermansen Mette N. , Hansen Kirsten S. , Chawes Bo L.
Published: June 2020

Background

Low adherence to asthma controllers is known to increase the risk of uncontrolled disease and poor health outcomes. We aimed to study risk factors of long‐term adherence to preventive medications in children and adolescents with asthma.

Methods

Adherence was assessed during a two‐year period in 155 children with asthma followed in a tertiary pediatric asthma outpatient clinic using percentage of days covered (PDC) based on physician prescriptions and pharmacy claims data. The risk factor analysis included age, sex, ethnicity, BMI, atopic comorbidity, spirometry incentives, and fractional exhaled nitric oxide (FeNO).

Results

Ninety‐five children, 50 (53%) males, mean age of 16.3 years (SD, 2.36), received at least one prescription for asthma controllers in the study period. Fifty‐two (54%) children were classified as non‐adherent with a PDC cutoff at 80%. Adherence was negatively associated with age: adherence ratio (AR) 0.84 (95% CI, 0.73‐0.95), P = .008; forced expiratory volume in 1 second (FEV1): AR per L 0.6 (0.91‐1.0), P = .03; unfilled inhaled beta‐2‐agonist prescription: AR 0.45 (0.23‐0.89), P = .02; and FeNO level: AR per ppb 0.98 (0.97‐0.99), P = .03, where age and FeNO retained significance in multivariate analysis. Type and number of asthma controllers were not associated with adherence.

Conclusions

This study shows low adherence to preventive medication among half of the children with asthma, which is associated with increasing age and FeNO level. Therefore, an extra effort should be directed toward teenagers transitioning from pediatric to adult medicine and toward inhaled corticosteroid‐treated patients with elevated FeNO to increase their adherence to asthma controllers.
Fertile male tortoiseshell cat with true chimerism 38,XY/38,XY
Authors: Bugno‐Poniewierska Monika , Kij Barbara , Witarski Wojciech , Wojtaszek Magdalena , Radko Anna , Podbielska Angelika , Szczerbal Izabela , Murphy William J.
Published: June 2020

The tortoiseshell coat colour is characteristic to female cats, and its occurrence in tomcats is very rare and associated with chromosome abnormalities (additional copy of X chromosome). The aim of this study was identification of the genetic basis of a case of tortoiseshell colour in a fertile Maine coon tomcat. Cytogenetic and molecular genetic studies were carried out with painting molecular probes (WCPP) specific to the X and Y sex chromosomes as well as a DNA microsatellite panel for the parentage verification of cats. Cytogenetic analysis revealed only a single set of sex chromosomes typical for male – 38,XY. The results of the microsatellite polymorphism obtained from DNA showed three alleles in locus FCA201 and four alleles in loci FCA149 and FCA441 in different tissues (blood, hair roots and testicles). Based on these results, the case was diagnosed as a true chimerism 38,XY/38,XY. To the best of our knowledge, this is the first case of a 38,XY/38,XY chimera diagnosed in cats, confirmed by genetic analysis.
Power to the people? Implications of the Clean Energy Package for the role of community ownership in Europe's energy transition
Authors: Roberts Joshua
Published: June 2020

Since the 1970s, citizens have organized through community energy initiatives to take ownership of renewable energy production. The European Union’s (EU) new Clean Energy for All Europeans Legislative Package (CEP) now formally recognizes this set of actors as ‘renewable’ and ‘citizen’ energy communities. This article aims to assess whether the CEP – namely the recast Renewable Energy Directive and the energy market design legislation – guarantees the role of energy communities in Europe’s energy transition. The article demonstrates how, due to their lack of recognition at EU level, internal energy market and competition rules, including the 2014 Guidelines on State Aid for Environmental Protection and Energy (EEAG), have overlooked the unique characteristics and challenges of energy communities, raising legal issues around equality and non‐discrimination. Ultimately, the article concludes that the CEP establishes an unprecedented framework with potential to support community ownership in the energy sector. However, transposition and implementation will test the legal strength of the new rules, as will the revision of the EEAG. The results of these processes will reinforce or impede the growth of energy communities throughout Europe.
Complexity of interruptions: Evidence supporting a non‐interruption‐based theory
Authors: Brazzolotto Paul , Michael George A.
Published: June 2020

Interruptions are known to be pervasive and harmful for concentration. It is also known that many factors can influence their effect, such as the complexity of the interrupting task. Less, however, is known about the processes underlying the resumption of the primary task, especially if the interrupting task is complex. Many hypotheses have been proposed but, as yet, it has not been possible to distinguish between their various qualities. In the current study, we carried out two experiments in which we manipulated the complexity of the interrupting task (either simple or complex) and the time between the end of the interrupting task and the resumption of the primary task (i.e., a break). Results showed that complex interrupting tasks led to longer resumption lags (RL) when there was no break, as has already been shown many times. However, while RL after simple interrupting tasks did not change as the break before resumption lengthened up to 1,500 ms, those after complex interrupting tasks decreased. Moreover, after a break of 3,000 ms, RL were longer overall. These results can only support the hypothesis based on task‐switching theories, but not hypotheses derived from interruption‐based models. Our findings therefore provide empirical evidence in support of explanations of complexity effects and the implications for research and application are discussed.
Ordinal patterns in long‐range dependent time series
Authors: Betken Annika , Buchsteiner Jannis , Dehling Herold , Münker Ines , Schnurr Alexander , Woerner Jeannette H.C.
Published: June 2020

We analyze the ordinal structure of long‐range dependent time series. To this end, we use so called ordinal patterns which describe the relative position of consecutive data points. We provide two estimators for the probabilities of ordinal patterns and prove limit theorems in different settings, namely stationarity and (less restrictive) stationary increments. In the second setting, we encounter a Rosenblatt distribution in the limit. We prove more general limit theorems for functions with Hermite rank 1 and 2. We derive the limit distribution for an estimation of the Hurst parameter H if it is higher than 3/4. Thus, our theorems complement results for lower values of H which can be found in the literature. Finally, we provide some simulations that illustrate our theoretical results.
Lessons from SARS‐CoV‐2 screening in a Brazilian organ transplant unit
Authors: de Sandes‐Freitas Tainá Veras , Canito Brasil Ivelise Regina , Oliveira Sales Maria Luiza de Mattos Brito , Studart e Neves Lunguinho Marina Seixas , Pimentel Ítalo Rossy Sousa , Josino da Costa Lucianna Auxi Teixeira , Esmeraldo Ronaldo de Matos
Published: June 2020

Protecting immunosuppressed patients during infectious disease outbreaks is crucial. During this novel coronavirus disease 2019 pandemic, preserving “clean areas” in hospitals assisting organ transplant recipients is key to protect them and to preserve transplantation activity. Evidence suggests that asymptomatic carriers might transmit the SARS‐CoV‐2, challenging the implementation of transmission preventive strategies. We report a single‐center experience using universal SARS‐CoV‐2 screening for all inpatients and newly admitted patients to an Organ Transplant Unit located in a region with significantly high community‐based transmission.
Efficacy and safety of chronic antimicrobial suppression therapy for left ventricular assist device driveline infections: A single‐center descriptive experience
Authors: Radcliffe Christopher , Doilicho Natnael , Niu Yu Si , Grant Matthew
Published: June 2020

Background

Driveline infection (DLI) is the most common left ventricular assist device (LVAD) infectious complication. Short‐term antimicrobial therapy and local debridement are the cornerstones of management for these infections, but the use of chronic antimicrobial suppression (CAS) therapy is not well characterized.

Methods

To better characterize the efficacy of CAS therapy, we performed a retrospective review of all patients (N = 219) receiving care at our tertiary transplant center with continuous‐flow LVADs placed between August 2007 and July 2019.

Results

A total of 24 patients were identified as having received CAS therapy as treatment for DLIs. The mean age was 56 years, 50% were female, and chronic kidney disease affected 63% of patients. Staphylococcus aureus accounted for half of all initial DLIs, and the mean length of CAS therapy was 486 days (range 48‐2287 days). All patients received per os regimens as suppression therapy. Adverse events impacted 5 of 24 patients (0.43 events per 1000 days). Overall, the use of CAS therapy led to successful outcomes in 50% of patients and 29% experienced treatment failures. The remaining patients experienced stable symptoms. Relapses were the most common cause of treatment failure, and three patients experienced reinfections while on CAS therapy.

Conclusions

Our study suggests that CAS therapy for DLIs can be well tolerated, and future studies are needed to determine which patients merit suppression.
Environmental relative humidity affects Schirmer tear test results in normal dogs
Authors: Yoon Angela , Liu Chin‐Chi , Carter Renee T. , Lewin Andrew C.
Published: June 2020

Objective

To investigate the effects of environmental temperature and relative humidity on tear test results in dogs.

Animals studied

22 normal dogs.

Procedures

Routine Schirmer tear tests (STT1) and phenol red thread tests (PRTT) were administered to normal dogs in four environmental conditions with different relative humidity (RH) and temperature (T). Environmental conditions (mean ± SD) included the following: normal indoor (RH = 49 ± 4%, T = 72 ± 2°F), outdoor (RH = 62 ± 11%, T = 85 ± 6°F), indoor high humidity (RH = 85 ± 6%, T = 71 ± 1°F), and indoor low humidity (RH = 39 ± 2%, T = 76 ± 1°F). ANCOVA models were used to assess for significant associations between tear test readings and RH/T (P < .05).

Results

A significant, direct positive relationship between RH and STT1 results was detected (y = 0.04909*X + 19.11, P = .006) but not between T and STT1. There was no significant relationship between PRTT and RH or T.

Conclusions

These results suggest that STT1 but not PRTT is affected by RH and that T does not influence STT1 or PRTT results in normal dogs. RH is unlikely, however, to cause clinically significant effects on STT1 readings in normal dogs when performed in average indoor conditions. Future studies should investigate the influence of RH on STT1 readings obtained in dogs with keratoconjunctivitis sicca.
Experimental Study of Flexible Electrohydrodynamic Conduction Pumping for Electronics Cooling
Authors: O'Connor Nathaniel J. , Castaneda Alexander J. , Christidis Pavolas N. , Vayas Tobar Nicolas , Talmor Michal , Yagoobi Jamal
Published: June 2020

As modern-day electronics develop, electronic devices become smaller, more powerful, and are expected to operate in more diverse configurations. However, the thermal control systems that help these devices maintain stable operation must advance as well to meet the demands. One such demand is the advent of flexible electronics for wearable technology, medical applications, and biology-inspired mechanisms. This paper presents the design and performance characteristics of flexible electrohydrodynamic (EHD) pumps, based on EHD conduction pumping technology in macro- and mesoscales. Unlike mechanical pumps, EHD conduction pumps have no moving parts, can be easily adjusted to the microscale, and have been shown to generate and control the flow of refrigerants for electronics cooling applications. However, these pumping devices have only been previously tested in rigid configurations unsuitable for use with flexible electronics. In this work, for the first time, the net flow generated by flexible EHD conduction pumps is measured on a flat plane in various configurations. In this study, the results show that the flexible EHD conduction pumps are capable of generating significant flow velocities in all size scales considered in this study, with and without bending. This study also proves the viability of screen printing as a manufacturing method for these pumps. The selection of working fluid for EHD conduction pumping is also a topic of discussion. Novec Engineered Fluids have been a popular choice for EHD pumping; however, long-term testing has shown that some Novec fluids degrade over time.
Mechanical and Tribological Studies of SU-8 Composites Filled With UHMWPE and Gum Acacia Under Dry and Bovine Serum Albumin Lubricated Conditions
Authors: Hirwani Jaswant K. , Sinha Sujeet K.
Published: June 2020

SU-8 polymer was mixed with ultrahigh-molecular weight polyethylene (UHMWPE) particles in various weight percentages (wt%) to make composites. Uniform distribution of filler material was confirmed by optical microscopy imaging. Cross-sectional scanning electron microscopy (SEM) analysis showed the formation of fibrillar structure of UHMWPE which helped bind UHMWPE particles with SU-8 matrix. Gum acacia made a coating on the UHMWPE particles and helped in binding with the matrix. The compressive Young’s modulus and strength of the composites were found to decrease with UHMWPE filler addition. The composites were tested in ball-on-disk tribometer using 12 mm diameter stainless steel (grade 304) ball under a normal load of 20 N and sliding speed of 32 mm/s. SU-8 with 25 wt% of UHMWPE showed coefficient of friction of 0.1 and specific wear-rate of 6.27 × 10−5 mm3/Nm which were 52% and 61%, respectively, lower in comparison with those of bulk UHMWPE tested in aqueous solution of bovine serum albumin (BSA). Adding 10 wt% of gum acacia to the SU-8/UHMWPE composite had beneficial effects on the wear-rate as the specific wear-rate of this hybrid composite further dropped to 4.6 × 10−5 mm3/Nm which was 71% lower than that of bulk UHMWPE.
Upscaling Reservoir Rock Porosity by Fractal Dimension Using Three-Dimensional Micro-Computed Tomography and Two-Dimensional Scanning Electron Microscope Images
Authors: Munawar Muhammad Jawad , Vega Sandra , Lin Chengyan , Alsuwaidi Mohammad , Ahsan Naveed , Bhakta Ritesh Ramesh
Published: June 2020

Scaling porosity of sedimentary rocks from the scale of measurement to the scale of interest is still a challenge. Upscaling of porosity can assist to accurately predict other petrophysical properties of rock at multiple scales. In this study, we use the two-dimensional (2D) scanning electron microscope (SEM) and three-dimensional (3D) X-ray micro-computed tomography (micro-CT) image to upscale porosity from the image scale to the core plug scale. A systematic imaging plan is deployed to capture rock properties of a carbonate and a sandstone sample, which are sensitive to the fractal nature of these rocks. Image analysis records wider pore spectrum (0.12–50 µm) in the carbonate sample than in sandstone (0.12–30 µm). The fractal dimensions are also higher in the carbonate than in the sandstone sample. Median, volume-weighted average of pore radius, and fractal dimensions derived from the image analysis are used as inputs in this equation. The results of the present study using this equation yielded to the best results on a resolution of 2.5 µm/voxel in the sandstone and 2.01 µm/voxel resolution in the carbonate sample for 3D micro-CT images, where fractal-scaling porosity matches well with the porosity measured at the core plug scale. The 2D SEM images provided a good estimation of porosity in the sandstone sample, where micro-CT imaging techniques could not capture the full pore spectrum. The fractal porosity equation showed promising results and offers a potential alternative way to estimate porosity when there are no routine core measurements available.
A Sustainable Trigeneration System for Residential Applications
Authors: Abu-Rayash Azzam , Dincer Ibrahim
Published: June 2020

This paper features the integration of two renewable energy sources, making a new trigeneration system for residential applications. The system is primarily powered by solar photovoltaic-thermal (PVT) along with geothermal energy. This trigeneration system consists of a ground source heat pump, solar system, high-grade and low-grade heat exchangers, a heat pump system, and a water storage tank (WST). The objective of this system is to provide the main commodities for residential use including domestic hot water (DHW), electricity, and space heating. The system is analyzed energetically and exergetically using thermodynamic-based concepts. The overall energy and exergy efficiencies of the proposed system are found to be 86.9% and 74.7%, respectively. In addition, the energy and exergy efficiencies of the PVT system are obtained to be 57.91% and 34.19%, respectively. The exergy destructions at the high-grade heat exchanger and the water storage tank add up to 36.9 kW, which makes up 80% of the total exergy destruction of the system. Additionally, parametric studies are conducted to evaluate the degree of impact that various important parameters have on the overall system performance.
Loss in Axial Compressor Bleed Systems
Authors: Grimshaw S. D. , Brind J. , Pullan G. , Seki R.
Published: June 2020

Loss in axial compressor bleed systems is quantified and the loss mechanisms are identified to determine how efficiency can be improved. For a given bleed air pressure requirement, reducing bleed system loss allows air to be bled from further upstream in the compressor, with benefits for the thermodynamic cycle. A definition of isentropic efficiency, which includes bleed flow is used to account for this. Two cases with similar bleed systems are studied: a low-speed, single-stage research compressor, and a large industrial gas turbine high-pressure compressor. A new method for characterizing bleed system loss is introduced, using research compressor test results as a demonstration case. A loss coefficient is defined for a control volume including only flow passing through the bleed system. The coefficient takes a measured value of 95% bleed system inlet dynamic head and is shown to be a weak function of compressor operating point and bleed rate, varying by ±2.2% over all tested conditions. This loss coefficient is the correct nondimensional metric for quantifying and comparing bleed system performance. Computations of the research compressor and industrial gas turbine compressor identify the loss mechanisms in the bleed system flow. In both cases, approximately two-thirds of total loss is due to shearing of a high-velocity jet at the rear face of the bleed slot, one-quarter is due to mixing in the plenum chamber, and the remainder occurs in the off-take duct. Therefore, the main objective of a designer should be to diffuse the flow within the bleed slot. A redesigned bleed slot geometry is presented that achieves this objective and reduces the loss coefficient by 31%.
Effect of instrument timbre on musical emotion recognition in normal-hearing listeners and cochlear implant users
Authors: Luo Xin , Warner Brendon
Published: June 2020

The effect of instrument timbre (e.g., piano, trumpet, organ, and violin) on musical emotion recognition was tested in normal-hearing (NH) listeners and cochlear implant (CI) users. NH performance was best with the piano, and did not change when melodies were normalized with a fixed tempo. CI performance was significantly better with the piano and trumpet than with the violin and organ when both tempo and mode cues were preserved, but not for the tempo-normalized melodies. The sharper temporal onsets of piano and trumpet may enhance CI users' perception of tempo cues important for musical emotion recognition.