bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluating webinar‐based training: a mixed methods study of trainee reactions toward digital web conferencing
Authors: Gegenfurtner Andreas , Zitt Alexander , Ebner Christian
Published: January 2020

What are the reactions of training participants toward digital webinar‐based training programs? Webinars are digital tools to deliver training and education through synchronous audiovisual communication among remotely located training instructors and participants. A webinar is a special case of web conferencing that serves the educational function of learning and teaching. Because the previous literature underemphasized the webinar process and qualitative learner experiences, the present study aimed to explore the reactions of 419 trainees toward 48 webinars in the four content areas supply chain management, industrial management, early childhood education and mathematics, the present study used a sequential mixed methods research design. The quantitative part of the study employed a multi‐item online questionnaire to measure satisfaction and reactions toward the webinar trainer; survey responses were analyzed to estimate mean differences across webinars. The qualitative part of the study employed narrative interviews with 23 trainees; interview transcripts were analyzed with qualitative content analysis to identify how the instructional design, webinar content and implementation can be improved for future web conferences. The findings indicate that early childhood education trainees had the highest satisfaction levels. Trainees preferred greater levels of learner‐teacher interaction, less time spent on discussing task solutions collaboratively and digital webinar recordings as a follow‐up possibility at home or in the workplace. Trainees also liked the fact that webinars afforded the possibility to deepen the content, to prepare for upcoming exams and to have virtual consultation hours with the facilitator. Furthermore, trainees preferred webinars no longer than 90 min and webinars on weekdays after work rather than at weekends. Optimal internet/broadband connections were perceived as a requirement across web conferencing and virtual classroom programs for effective digital education. Implications of the findings for educational technology, human resource development and professional learning are discussed.
Worldwide prevalence of sexual harassment towards nurses: A comprehensive meta‐analysis of observational studies
Authors: Lu Li , Dong Min , Lok Grace K. I. , Feng Yuan , Wang Gang , Ng Chee H. , Ungvari Gabor S. , Xiang Yu‐Tao
Published: January 2020

Aims

Sexual harassment towards nurses is a major concern universally, but no meta‐analysis on the worldwide prevalence of sexual harassment towards nurses has yet been published. This study examined the worldwide prevalence of sexual harassment against nurses and explored its moderating factors.

Design

Meta‐analysis of observational studies.

Data sources

The PubMed, PsycINFO, EMBASE, and Web of Science databases from their commencement date to February 2018 were systematically and independently searched by two investigators.

Review methods

Data on the prevalence of sexual harassment experienced by nurses were extracted and pooled using the random‐effects model.

Results

A total of 43 studies covering 52,345 nurses were included in the analyses. Female nurses accounted for 83.87% of the 32,970 subjects in 25 studies with available data on gender ratio. The prevalence of sexual harassment towards nurses in the past 12 months and during nursing career were 12.6% (95% CI: 10.9–14.4%) and 53.4% (95% CI: 23.1–83.7%), respectively. Gender, use of the WHO questionnaires, lower middle‐income and high‐income countries, sample size, survey year, and mean age of subjects were significantly associated with the prevalence of sexual harassment.

Conclusion

The high prevalence of sexual harassment against nurses found in this meta‐analysis represents the ongoing sexism and deleterious effects (e.g., poor work quality and efficiency, increased stress and job dissatisfaction) in the profession. Appropriate preventive measures, training, and empowerment of nurses are needed to ensure workplace safety and equality in this profession.

Impact

The study addressed the worldwide prevalence of sexual harassment against nurses and its moderating factors. Health authorities and hospital administrators should develop organizational policy and preventive strategies to ensure nurses’ workplace safety and equality.
Trachea and lung anatomy applied to clinical and surgical procedures in Sapajus libidinosus (Spix, 1823)
Authors: Falcão Brunna Muniz Rodrigues , Vieira Ana Karoline Rocha , de Souza Joyce Galvão , Medeiros Gildenor Xavier , de Menezes Danilo José Ayres , dos Santos José Rômulo Soares
Published: January 2020

Background

The objective of the present study was to study the anatomy of the respiratory system of Sapajus libidinosus.

Methods

Ten corpses of adult animals were used. To analyze the bronchial tree, transparent acetic silicone was injected and then dissected.

Results

The trachea presented a mean of 32 rings. These spaces were delimited for tracheostomy and tracheotomy between the 1st and 3rd ring or between the 9th and 11th ring, and for thoracocentesis at the 7th or 8th intercostal space. For tracheostomy and tracheotomy, the best access point was in the ventral region of the neck and transverse incision of the rings. For thoracocentesis, cranioventral insertion of the catheter is recommended in the 8th intercostal space.

Conclusions

The trachea and lung anatomy applied to clinical and surgical procedures the robust capuchin monkey is similar to both wild and domestic carnivores.
Poly lactic‐co‐glycolic acid scaffold loaded with plasmid DNA encoding fibroblast growth factor‐2 promotes periodontal ligament regeneration of replanted teeth
Authors: Jiang Liming , Ding Zhenjiang , Xia Shang , Liu Yao , Lei Shuang , Zhong Ming , Chen Xu
Published: January 2020

Objective

This study investigated the effects of poly lactic‐co‐glycolic acid (PLGA) loaded with plasmid DNA encoding fibroblast growth factor‐2 (pFGF‐2) on human periodontal ligament cells (hPDLCs) in vitro and evaluated the ability of the PLGA/pFGF‐2 scaffold to promote periodontal ligament (PDL) regeneration in a beagle dog teeth avulsion animal model.

Background

Growth factor and scaffold play important roles in PDL regeneration. PLGA is a kind of biodegradable and biocompatible polymer that can be used as a carrier to deliver growth factors or genes. FGF‐2 can induce potent proliferative responses, promote cell migration and regulate the production of extracellular matrix. Therefore, a gene‐activated matrix composed of scaffold and genes is supposed to be a superior approach for promoting tissue regeneration.

Methods

In this study, PLGA and PLGA/pFGF‐2 scaffolds were fabricated using electrospinning. The characterization of scaffolds was shown by scanning electron microscope (SEM) and transmission electron microscope (TEM). dsDNA HS was used to test the plasmid release of PLGA/pFGF‐2 scaffold. The viability and proliferation of hPDLCs on the two kinds of scaffolds were evaluated by the CCK‐8 assay, and the expression of collagen I and scleraxis were analysed by RT‐qPCR. The roots of avulsed teeth were covered by the two types of scaffolds and replanted into the alveolar pockets in beagles. Haematoxylin‐eosin and Masson staining were used to evaluate the effects of PLGA/pFGF‐2 scaffold on promoting PDL regeneration.

Results

The smooth and uniform fibres can be observed in both scaffolds, and the plasmids were randomly distributed in the PLGA/pFGF‐2 scaffold. dsDNA HS analysis demonstrated that the PLGA/pFGF‐2 scaffold released up to 123 ng pFGF‐2 over 21 days in a sustained manner without any obvious burst release. The PLGA/pFGF‐2 scaffold promoted the proliferation of hPDLCs and increased the expression levels of collagen I and scleraxis compared with PLGA scaffold. Animal experiments showed that more regular PDL‐like tissues and less root surface resorption occurred in the PLGA/pFGF‐2 scaffold group compared with the PLGA scaffold group.

Conclusions

The PLGA/pFGF‐2 scaffold promoted hPDLCs proliferation and facilitated periodontal ligament‐related differentiation. The PLGA/pFGF‐2 scaffold possesses excellent biological characteristics and could be used as a promising biomaterial for improving the treatment prognosis of replanted tooth.
Combined genotype and phenotype analyses reveal patterns of genomic adaptation to local environments in the subtropical oak Quercus acutissima
Authors: Gao Jie , Liu Zhi‐Long , Zhao Wei , Tomlinson Kyle W. , Xia Shang‐Wen , Zeng Qing‐Yin , Wang Xiao‐Ru , Chen Jin
Published: January 2020

Understanding the effects of the demographic dynamics and environmental heterogeneity on the genomic variation of forest species is important, not only for uncovering the evolutionary history of the species, but also for predicting their ability to adapt to climate change. In this study, we combined a common garden experiment with range‐wide population genomics analyses to infer the demographic history and characterize patterns of local adaptation in a subtropical oak species, Quercus acutissima (Carruthers). We scanned approximately 8% of the oak genome using a balanced representation of both genic and non‐genic regions and identified a total of 55 361 single nucleotide polymorphisms (SNPs) in 167 trees. Genomic diversity analyses revealed an east–west split in the species distribution range. Coalescent‐based model simulations inferred a late Pleistocene divergence in Q. acutissima between the east and west groups as well as subsequent preglaciation population expansion events. Consistent with observed genetic differentiation, morphological traits also showed east–west differentiation and the biomass allocation in seedlings was significantly associated with precipitation. Environment was found to have a significant and stronger impact on the non‐neutral than the neutral SNPs, and also significantly associated with the phenotypic differentiation, suggesting that, apart from the geography, environment had played a role in determining non‐neutral and phenotypic variation. Our approach, which combined a common garden experiment with landscape genomics data, validated the hypothesis of local adaptation of this long‐lived oak tree of subtropical China. Our study joins the small number of studies that have combined genotypic and phenotypic data to detect patterns of local adaptation.
Changes in the promoter of a defender against apoptotic cell death gene affect its expression in upland cotton
Authors: Bao Ying , Mei Yu‐Qin , Xu Xin , Liu Ye , Wu Zhen‐Yang
Published: January 2020

The DAD1 (defender against apoptotic cell death) gene is a negative regulator of programmed cell death. It plays important roles in plant growth, development, environmental adaptation, and aging. We examined whether and how the expression of DAD1 gene is affected by the promoter changes in the allotetraploid upland cotton (Gossypium hirsutum L.). We compared the expression status of the genes in the leaves of an elite cultivar and a wild variety of G. hirsutum, and cloned and analyzed a 1.3‐kb promoter region of the genes in two cotton types. Results revealed that the expression of a subgenomic homoeolog of DAD1 (DAD1

At
) was significantly upregulated in leaves of the cultivated cotton when compared with that in a wild cotton. In addition, we identified 18 variations, including 14 single nucleotide polymorphisms and four indels between the promoters of the two cotton types. We detected at least 10 of 18 variations in the promoters related to possible cis‐regulatory elements. Further transient tobacco assays using heterogeneous DAD1

At
promoter::GUS fusion showed that the activity of the DAD1

At
promoter in the cultivated cotton was stronger than that in the wild cotton, which suggested a dynamic change in the DAD1

At
promoter during genetic divergence of the two cottons. This study provides an example of how gene expression could be affected by specific changes in the gene promoter.
The endothelial function biomarker soluble E‐selectin is associated with nonalcoholic fatty liver disease
Authors: Simons Nynke , Bijnen Mitchell , Wouters Kristiaan A. M. , Rensen Sander S. , Beulens Joline W. J. , van Greevenbroek Marleen M. J. , ’t Hart Leen M. , Greve Jan Willem M. , van der Kallen Carla J. H. , Schaper Nicolaas C. , Schalkwijk Casper G. , Stehouwer Coen D. A. , Brouwers Martijn C. G. J.
Published: January 2020

Background & Aims

Plasma soluble E‐selectin (sE‐selectin) is a frequently used biomarker of systemic endothelial dysfunction. The present study explored the relationship between nonalcoholic fatty liver disease (NAFLD) and plasma sE‐selectin levels.

Methods

Expression of E‐selectin in liver, visceral adipose tissue (VAT) and muscle was studied in relation to plasma sE‐selectin in severely obese individuals (n = 74). The course of hepatic E‐selectin expression in relation to hepatic steatosis and inflammation was examined in C57BL/6J LDLR−/− mice on a Western‐type diet. The relationship between biomarkers of NAFLD, that is, plasma aminotransferase (ALT) and NAFLD susceptibility genes (rs738409 [PNPLA3] and rs1260326 [GCKR]), and plasma sE‐selectin was studied in the combined CODAM (n = 571) and Hoorn (n = 694) studies.

Results

E‐selectin expression in liver, not VAT or muscle, was associated with plasma sE‐selectin in severely obese individuals (β = 0.26; 95% CI: 0.05‐0.47). NAFLD severity was associated with hepatic E‐selectin expression (P = .02) and plasma sE‐selectin (P = .003). LDLR−/− mice on a Western‐type diet displayed increased hepatic E‐selectin expression that followed the same course as hepatic inflammation, but not steatosis. In the CODAM study, plasma ALT was associated with plasma sE‐selectin, independent of potential confounders (β = 0.25; 95% CI: 0.16‐0.34). Both rs738409 and rs1260326 were associated with higher plasma sE‐selectin in the combined CODAM and Hoorn studies (P = .01 and P = .004 respectively).

Conclusions

NAFLD and related markers are associated with higher expression of hepatic E‐selectin and higher levels of plasma sE‐selectin. Further studies are required to investigate the role of E‐selectin in the pathogenesis of NAFLD and the applicability of sE‐selectin as a plasma biomarker of NAFLD/NASH.
Plant hemoglobins: a journey from unicellular green algae to vascular plants
Authors: Becana Manuel , Yruela Inmaculada , Sarath Gautam , Catalán Pilar , Hargrove Mark S.
Published: January 2020

Globins (Glbs) are widely distributed in archaea, bacteria and eukaryotes. They can be classified into proteins with 2/2 or 3/3 α‐helical folding around the heme cavity. Both types of Glbs occur in green algae, bryophytes and vascular plants. The Glbs of angiosperms have been more intensively studied, and several protein structures have been solved. They can be hexacoordinate or pentacoordinate, depending on whether a histidine is coordinating or not at the sixth position of the iron atom. The 3/3 Glbs of class 1 and the 2/2 Glbs (also called class 3 in plants) are present in all angiosperms, whereas the 3/3 Glbs of class 2 have been only found in early angiosperms and eudicots. The three Glb classes are expected to play different roles. Class 1 Glbs are involved in hypoxia responses and modulate NO concentration, which may explain their roles in plant morphogenesis, hormone signaling, cell fate determination, nutrient deficiency, nitrogen metabolism and plant–microorganism symbioses. Symbiotic Glbs derive from class 1 or class 2 Glbs and transport O2 in nodules. The physiological roles of class 2 and class 3 Glbs are poorly defined but could involve O2 and NO transport and/or metabolism, respectively. More research is warranted on these intriguing proteins to determine their non‐redundant functions.
Metabolic rewiring of synthetic pyruvate dehydrogenase bypasses for acetone production in cyanobacteria
Authors: Lee Hyun Jeong , Son Jigyeong , Sim Sang Jun , Woo Han Min
Published: January 2020

Designing synthetic pathways for efficient CO2 fixation and conversion is essential for sustainable chemical production. Here we have designed a synthetic acetate‐acetyl‐CoA/malonyl‐CoA (AAM) bypass to overcome an enzymatic activity of pyruvate dehydrogenase complex. This synthetic pathway utilizes acetate assimilation and carbon rearrangements using a methyl malonyl‐CoA carboxyltransferase. We demonstrated direct conversion of CO2 into acetyl‐CoA‐derived acetone as an example in photosynthetic Synechococcus elongatus PCC 7942 by increasing the acetyl‐CoA pools. The engineered cyanobacterial strain with the AAM‐bypass produced 0.41 g/L of acetone at 0.71 m/day of molar productivity. This work clearly shows that the synthetic pyruvate dehydrogenase bypass (AAM‐bypass) is a key factor for the high‐level production of an acetyl‐CoA‐derived chemical in photosynthetic organisms.
Genotypic variation in source and sink traits affects the response of photosynthesis and growth to elevated atmospheric CO2
Authors: Fabre Denis , Dingkuhn Michael , Yin Xinyou , Clément‐Vidal Anne , Roques Sandrine , Soutiras Armelle , Luquet Delphine
Published: January 2020

This study aimed to understand the response of photosynthesis and growth to e‐CO2 conditions (800 vs. 400 μmol mol−1) of rice genotypes differing in source–sink relationships. A proxy trait called local C source–sink ratio was defined as the ratio of flag leaf area to the number of spikelets on the corresponding panicle, and five genotypes differing in this ratio were grown in a controlled greenhouse. Differential CO2 resources were applied either during the 2 weeks following heading (EXP1) or during the whole growth cycle (EXP2). Under e‐CO2, low source–sink ratio cultivars (LSS) had greater gains in photosynthesis, and they accumulated less nonstructural carbohydrate in the flag leaf than high source–sink ratio cultivars (HSS). In EXP2, grain yield and biomass gain was also greater in LSS probably caused by their strong sink. Photosynthetic capacity response to e‐CO2 was negatively correlated across genotypes with local C source–sink ratio, a trait highly conserved across environments. HSS were sink‐limited under e‐CO2, probably associated with low triose phosphate utilization (TPU) capacity. We suggest that the local C source–sink ratio is a potential target for selecting more CO2‐responsive cultivars, pending validation for a broader genotypic spectrum and for field conditions.
Utilization and efficacy of palivizumab for children with Down syndrome
Authors: Kimura Takeshi , Takeuchi Masato , Kawakami Koji
Published: January 2020

Background

Palivizumab is a prophylactic drug used for severe respiratory syncytial virus (RSV) infection in young children with high‐risk factors, such as prematurity and congenital heart diseases. Although Japan expanded the use of palivizumab for Down syndrome (DS) in 2013 regardless of additional high‐risk factors, there is not enough evidence to support its use. We analyzed health insurance claim data from the JMDC (Tokyo, Japan) to investigate the prescription pattern and efficacy of palivizumab in children with DS.

Methods

We enrolled children of ≤24 months of age with DS at the start of the RSV epidemic season (2007–2015). We compared the risk of RSV‐related admission with and without palivizumab prophylaxis using mixed effects logistic regression models accounting for patient‐level clustering.

Results

Of 632 children, 30% (81/268) and 83% (303/364) received palivizumab before and after the expanded program (2007–2012 and 2013–2015), respectively. Among children with DS but without additional high‐risk factors (n = 135), palivizumab use surged from 0% (0/62) to 73% (53/73). In the whole study population, RSV‐related hospitalization occurred in 4.2% (16/384) patients with prophylaxis and 6.0% (15/248) patients without prophylaxis. The multivariate analysis revealed that palivizumab was associated with reduced RSV‐related hospitalization (odds ratio: 0.41, 95% confidence interval: 0.18–0.92, P = 0.03).

Conclusions

Virtually all children with DS in Japan have now received palivizumab, the use of which was associated with a reduction in RSV‐related hospitalization in DS. Further evidence is required to clarify whether palivizumab prophylaxis should be risk‐tailored or universal for DS.
Changes in the mast cell distribution in the canine ovary and uterus throughout the oestrous cycle
Authors: Hamouzova Pavla , Cizek Petr , Bartoskova Alena , Vitasek Roman , Tichy Frantisek
Published: January 2020

This is the first study describing the relation between the phase of the oestrous cycle and the number of mast cells (MCs) in the canine ovaries and uterine horns. The total number of MCs was counted in cortex ovarii, medulla ovarii, endometrium and myometrium. The number of MCs was compared in all of these areas among the bitches in the early follicular phase, luteal phase and anoestrus. MCs were the most numerous in the early follicular phase and in the luteal phase; however, they were significantly less numerous during anoestrus. Based on the results, it was concluded that the number of MCs in ovaries and uterine horns fluctuates during the oestrous cycle. The results of this study may contribute to clarifying the role of MCs in the reproductive organs of bitches.
Understory responses to restoration in aspen‐conifer forests around the Lake Tahoe Basin: residual stand attributes predict recovery
Authors: Dagley Christa M. , Berrill John‐Pascal , Coppeto Stephanie A. , Eschtruth Anne K.
Published: January 2020

The removal of conifers from aspen (Populus tremuloides) stands is being undertaken throughout the western United States to restore aspen for local‐ and landscape‐level biodiversity. Current practices include mechanically removing conifers or hand thinning, piling, and burning cut conifers in and adjacent to aspen‐conifer stands. To evaluate the effectiveness of restoration treatments, we examined tree regeneration and herbaceous vegetation cover in thinned, thinned and pile burned, and non‐thinned control stands. Growth rates of small conifer saplings threatening to outcompete and replace aspen were also measured. Two to four years after pile burning, herbaceous vegetation cover within the footprint of burned piles (i.e. burn scars) was 35–73% of that in adjacent areas. Aspen was more likely to regenerate inside burn scars where fewer surrounding trees were true firs. Conifer seedlings were more likely to regenerate in burn scars where more of the surrounding trees were conifers (pine or fir) as opposed to aspen. Fir saplings had much slower growth than did aspen saplings. Overall, our findings show that restoration treatments are promoting desirable outcomes such as enhancing aspen regeneration but that follow‐up treatments will be needed to remove numerous conifer seedlings becoming established after restoration activities. Eliminating conifers, while they are small, growing slowly, and contributing little to fuel loads may be an economical way to prolong restoration treatment effectiveness.
Mycobacterial antigens accumulation in foamy macrophages in murine pulmonary tuberculosis lesions: Association with necrosis and making of cavities
Authors: Riaz Syeda Mariam , Bjune Gunnar Aksel , Wiker Harald G. , Sviland Lisbet , Mustafa Tehmina
Published: January 2020

Understanding mechanisms of cavitation in tuberculosis (TB) is the missing link that could advance the field towards better control of the infection. Descriptions of human TB suggest that postprimary TB begins as lipid pneumonia of foamy macrophages that undergoes caseating necrosis and fragmentation to produce cavities. This study aimed to investigate the various mycobacterial antigens accumulating in foamy macrophages and their relation to tissue destruction and necrosis. Pulmonary tissues from mice with slowly progressive TB were studied for histopathology, acid‐fast bacilli (AFB) and presence of mycobacterial antigens. Digital quantification using Aperio ImageScope was done. Until week 12 postinfection, mice were healthy, and lesions were small with scarce AFB and mycobacterial antigens. Colony‐forming units (CFUs) increased exponentially. At week 16‐33, mice were sick, macrophages attained foamy appearance with an increase in antigens (P < .05), 1.5 log increase in CFUs and an approximately onefold increase in AFB. At week 37‐41, mice started dying with a shift in morphology towards necrosis. A >20‐fold increase in mycobacterial antigens was observed with only less than one log increase in CFUs and sevenfold increase in AFB. Secreted antigens were significantly (P < .05) higher compared to cell‐wall antigens throughout infection. Focal areas of necrosis were associated with an approximately 40‐fold increase in antigen MPT46, functionally active thioredoxin, and a significant increase in all secreted antigens. In conclusion, mycobacterial antigens accumulate in the foamy macrophages in TB lesions during slowly progressive murine pulmonary TB. Secreted antigens and MPT46 correlated with necrosis, thereby implying that they might trigger the formation of cavities.
Missing the Dictator? The Effect of the Image of Authoritarian Past on Support for Democracy in Latin America
Authors: Durán Iván M. , Trillas Francesc
Published: January 2020

Objective

This article examines to what extent the image that individuals have about past authoritarian regimes affects citizens’ support for contemporary democracies.

Methods

Drawing on the 2010 Latinobarómetro survey, we test whether the “deviation in evaluations” (i.e., the difference between the individuals’ evaluation of the present country economic situation and the individuals’ evaluation of the last authoritarian regime) affect support for democracy in Latin America.

Results

We found that as the assessment of the last authoritarian government outperforms that of the present country economy, individuals are less likely to support democracy, and this effect is stronger for old people.

Conclusion

This finding reveals important challenges for democratic consolidation: emerging democracies do not only have to display a good economic performance by themselves, but they also must prove to be better than previous authoritarian regimes.
Inverse identification of constitutive parameters from heat source fields: A local approach applied to hyperelasticity
Authors: Charlès Sylvain , Le Cam Jean‐Benoît
Published: January 2020

In this paper, a new inverse identification method of constitutive parameters is developed from full kinematic and thermal field measurements. It consists in reconstructing the heat source field from two different approaches by using the heat diffusion equation. The first one requires the temperature field measurement and the value of the thermophysical parameters. The second one is based on the kinematic field measurement and the choice of a thermo‐hyperelastic model that contains the parameters to be identified. The identification is carried out at the local scale, ie, at any point of the heat source field, without using the boundary conditions. In the present work, the method is applied to the challenging case of hyperelasticity from a heterogeneous test. Due to large deformations undergone by the rubber specimen tested, a motion compensation technique is developed to plot the kinematic and the thermal fields at the same points before reconstructing the heterogeneous heat source field. In the present case, the constitutive parameter of the Neo‐Hookean model has been identified, and its distribution has been characterized with respect to the strain state at the surface of a cross‐shaped specimen.
Viral enteritis in intestinal transplant recipients
Authors: Servais Abigail M. , Keck Megan , Leick Mary , Mercer David F. , Langnas Alan N. , Grant Wendy J. , Vargas Luciano M. , Merani Shaheed , Florescu Diana F.
Published: January 2020

Intestinal transplant recipients (ITR) are at high risk for infections due to the high level of immunosuppression required to prevent rejection. There are limited data regarding viral enteritis post‐intestinal transplantation. We retrospectively reviewed ITR transplanted between January 2008 and December 2016. Descriptive statistics, including mean (standard deviation) and median (range), were performed. Sixty‐one (43.9%) of the 139 transplanted patients had viral enteritis: 26% norovirus, 25% adenovirus, and 9% each rotavirus and sapovirus. The median age of pediatric patients was 1.6 years (0.4‐16.9) and for adults 36.3 years (27.1‐48.2). Fifty‐seven (58%) of 99 pediatric ITR had viral enteritis compared to 4 (10%) of 40 adult ITR. Median time‐to‐clinical resolution of enteritis for all patients was 5 days (1‐92). Standard of care therapies administered: anti‐motility agents (10%), anti‐emetics agents (14%), and intravenous fluids (42%). There was a higher incidence of viral enteritis in pediatric compared to adults ITR. The majority of viral enteritis episodes resolved within 1 week and were treated with supportive therapy.
Systematic Review Study: A Comparative Analysis of the State of the Art of Green Criminology
Authors: Konrad Ana Christina , Turatti Luciana , Flores Cíntia Rosina , Konrad Odorico
Published: January 2020

Understanding the complex phenomena related to environmental damage requires multidisciplinary analyzes capable of producing different scientific perspectives. Based on the problems arising from issues involving environmental damage to natural resources, Flores, Konrad and Flores (2017) evaluated the studies about green criminology globally, using articles retrieved from indexed publications and available in digital databases. The present study aimed to survey the contributions that were added since the previous survey, to contribute to the understanding of what constitutes the essence of green criminology. To meet this purpose, we analyzed scientific articles published after the period investigated by Flores, Konrad and Flores (2017), which also allowed the comparison with the existing data. We employed a qualitative approach and the methodological procedure was a systematic bibliographic review. We concluded that in the last three years there has been an advance in studies about green criminology. Still, there has been a limited number of studies published in this area. Research on the theory may be limited by political and geographical issues that inhibit the plurality of spatial and local perceptions regarding the theme. Also, they restrict preventive actions to environmental damage due to lack of knowledge and research, as the theory acts directly on preventive measures and protection of nature.
Characterization of a Custom-Made Digital Light Processing Stereolithographic Printer Based on a Slanted Groove Micromixer Geometry
Authors: Valentinčič Joško , Prijatelj Miha , Jerman Marko , Lebar Andrej , Sabotin Izidor
Published: January 2020

A custom-made stereolithographic printer using a digital light processing optical (DLP) system based on a digital micromirror device (DMD) was characterized. Several sizes of slanted grooved micromixers (SGM) were produced and typical dimensions were measured and compared to nominal values. The results show that the developed SLA printer is precise enough to be used for prototyping of larger microfluidic devices. The lateral geometries of the smallest printed micromixer designs deviated less than 20 μm from the nominal values and related feature depths deviated for less than 15 μm. However, further modifications are needed in order to improve the repeatability, accuracy, and printing resolution.
Direct Current/Alternating Current Magnetohydrodynamic Micropump of a Hybrid Nanofluid Through a Vertical Annulus With Heat Transfer
Authors: El-Masry Y. A. S. , Abd Elmaboud Y. , Abdel-Sattar M. A.
Published: January 2020

Gold nanoparticles (AuNPs) are increasingly being widely used in several biomedical applications for their compatibility of synthesis and less toxicity. The mixture of gold and titanium oxide nanoparticles is suspended in water to make a new class of nanofluid, which is called a hybrid nanofluid. The problem of direct current (DC)/alternating current (AC) magnetohydrodynamic (MHD) micropump of the hybrid nanofluid through a porous medium in the gap between vertical coaxial microtubes with heat transfer has been discussed. The mathematical model is established and then solved with the help of the Laplace transform. The inversion of the transformed functions is calculated numerically. The velocity, the flowrate, the pressure, and the heat transfer are discussed graphically. The higher concentration of the mixture of particles enhances the stream so that the required pressure is small. Moreover, it is found that the variation of the Nusselt number is noticeable by increasing the concentrations of nanoparticles, but this variation vanishes near the outer tube.
Constructing Oscillating Function-Based Covariance Matrix to Allow Negative Correlations in Gaussian Random Field Models for Uncertainty Quantification
Authors: Xu Hongyi
Published: January 2020

Gaussian random field has been widely applied to quantify high-dimensional uncertainties in the spatial or temporal domain. A common practice in Gaussian random field modeling is to use the exponential function to represent the covariance matrix. However, the exponential function-based covariance formulation does not allow negative values, thus it cannot capture the negative correlation between two locations in the input domain. To resolve this issue, this work reports new formulations of the covariance matrix based on oscillating functions, and a process of reconstructing Gaussian random field models from observation data. The proposed covariance functions are compared with the traditional exponential covariance functions on two test cases, where the datasets show negative correlations. The results of comparative studies demonstrate that the proposed formulations improve the accuracy of Gaussian random field models effectively.
Lateral Load Transfer due to Sloshing Cargo in Partially Filled Containers
Authors: Otremba Frank , Romero Navarrete José A.
Published: January 2020

The interaction of the liquid cargo and its carrying vehicle has been a common research subject, aiming at clarifying the potential effects of the mobility characteristics of such type of cargo, on the overall safety performance of the vehicle. While there has been extensive research on this topic, including both experimental and theoretical approaches, the comparative experimental testing of sloshing and non-sloshing cargoes has been only limited. In this paper, a scaled-down testing device that operates under the principles of a tilt table, is described and used to comparatively assess the effects, of a sloshing and non-sloshing cargo, on the lateral load transfer in the vehicle, as a function of the fill level and of the rate at which the lateral acceleration input is exerted on the vehicle-cargo system. Results suggest that the sloshing cargo generates greater load transfers, regardless of the fill level and acceleration rate input. As an average, the sloshing cargo generates a 14.75% greater load transfer.
Thermodynamic Modelling of Superfluid Stirling Cryocoolers
Authors: Domenikos G.-R. , Bitsikas P. , Rogdakis E.
Published: January 2020

The aim of this paper is to describe and thermodynamically model cryogenic Stirling refrigerators, using Helium in its different forms as the working medium. Helium has unique properties at cryogenic temperatures forming a superfluid. The cryogenic Stirling refrigerators with Helium at such low temperatures make use of the properties of this superfluid nature of Helium, thus they are referred to as Superfluid Stirling Refrigerators (SSR). To make use of these remarkable properties of superfluid helium a different version of Stirling refrigerator is used where superleaks are introduced in the pistons in order to let the superfluid part flow freely but constrain the normal fluid. This cooling procedure has an upper temperature limit as it is based on the superfluidity of helium, hence all the workings of this cycle must be well below the Lambda line. In addition, different models are needed and are used for the different isotopes of helium as their atomic spin nature is different and therefore their behavior at temperatures near absolute zero. In this study of SSR cryocoolers great care is being given towards the thermodynamic behavior of the entire system and working media, as well as different designs of the apparatus.
Power Electronics Sliding Mode Control Design for Photovoltaic Energy Conversion Systems
Authors: Gursoy Mehmetcan , Lozowski Andy G. , Wang Xin
Published: January 2020

The manuscript presents a novel power electronics sliding mode control design for photovoltaic energy conversion systems. In order to maximize the power generation from solar panels, P&O maximum power point tracking algorithm is applied. The purposed first and high-order sliding mode control techniques are developed to overcome the irradiance and load fluctuation challenge, and to optimize the power conversion efficiency. Compared with the first-order method, the higher-order sliding mode approach can significantly reduce the chattering effect in the Buck-Boost converter. The output of the DC-DC converter is then fed into a voltage-oriented control based SVPWM inverter for three-phase AC power generation. Computer simulation studies have shown the effectiveness and robustness of the proposed power electronics control approach for solar energy systems.
Effect of Shear Overloads on Crack Propagation in Al-7075 Under In-Plane Biaxial Fatigue Loading
Authors: Singh Abhay K. , Datta Siddhant , Chattopadhyay Aditi , Phan Nam
Published: January 2020

A cruciform specimen of Al 7075-T651 is used to study crack propagation behavior in an in-plane biaxial fatigue loading subjected to shear overloads of different magnitudes, which were applied at different crack lengths. The microscale fracture features of the specimen were identified and compared for the pre-overload region, overload region, and post-overload region at two different values of crack lengths, using scanning electron microscopy (SEM). It was observed that the transient region, created by the application of the shear overload, improved the fatigue life of the specimen. The overload also displayed an instant upsurge in the fatigue crack growth rate, which was immediately followed by a sharp crack retardation. The crack growth rate was restored once it came out of the transient zone and traveled a distance equal to the value of recovery distance. Both, the magnitude of the applied shear overload and the location of overload with respect to crack length seemed to affect the size of the transient zone, fatigue life, crack growth rate, and recovery distance. Investigations made on the fracture surfaces revealed that there is no significant change in the microscale fracture features when the overload was applied at different values of crack lengths; however, a clear and significant difference in the fracture features appear when the surfaces of the pre-overload region, overload region, and post-overload region are compared.
Improving Power and Frequency Bandwidth of a Magnetic Spring Based Vibration Energy Harvester Using FR4 Spring-Guided Magnet
Authors: Aldawood Ghufran , Nguyen Hieu Tri , Bardaweel Hamzeh
Published: January 2020

This article introduces an enhanced magnetic spring based energy harvester design suitable for harvesting kinetic energy from vibrations that are characterized by low acceleration levels. The presented design consists of a levitated magnet, an FR4 spring-guided magnet and coils. Prototypes of the enhanced harvester design are fabricated and characterized experimentally. For comparison, a traditional magnetic spring based vibration energy harvester is fabricated and characterized experimentally. Results from experiments confirm the superiority of the proposed enhanced harvester design over the traditional harvester design. At 0.1g [m/s2], the peak power of the enhanced harvester reaches approximately 40 times the peak power generated by the traditional harvester. At this acceleration level both enhanced and traditional harvesters exhibit approximately 0.4 [Hz] frequency bandwidth. At 0.3g [m/s2] the improvement in power generated by the enhanced harvester is approximately 400% compared to the power generated by the traditional harvester while the frequency bandwidth increases by 80%.
Miniature Humanoid Upgrade for Material Handling Tasks in Humanoid Challenge
Authors: Sohn Kiwon , Lee Jeongkyu , Huang Kevin
Published: January 2020

This paper presents the development of a miniature humanoid platform for various material-handling tasks. Since 2018, three universities in Connecticut (University of Hartford, University of Bridgeport and Trinity College) have made continuous efforts on building and organizing the annual robotics competition which is titled as Humanoid Challenge (HC). While most robotics competitions are concentrating on mobile robot and its navigation, HC focuses on the small-sized bipedal robot platform (miniature humanoid) and its task-execution in human-centered-environments. Inspired from DRC Trials 2013 and Finals 2015, the participants in the competition are asked to complete six different tasks in a mock-up of a disaster. To assist students and teams who are interested in participating in the competition, the authors in three universities share the progresses with both hardware and software components of each teams robot platform through this paper.
Measured Performance of a Variable Transmission Glazing System
Authors: Al-Dossary Ali , Dillon Heather , Farina Jordan
Published: January 2020

Variable Transmission Glazing (VTG) windows are an energy efficiency measures that have relatively high first cost. This paper describes the in-situ performance of VTG installed in an atrium space at the University of Portland. An experiment was conducted using thermocouples and photosensors to examine temperature gradients and solar gains across electrochromic glazing windows to quantify the performance of the installed system in terms of energy and cost saving. The system performance was measured with an average efficiency of 98.73% when the VTG was operating. The annual savings of the glazing system installed was estimated to be $7,683.
A Probabilistic Fatigue Damage Model for Describing the Entire Set of Fatigue Test Data of the Same Material
Authors: Le Xiaobin
Published: January 2020

One typical widely-accepted approach for describing the fatigue test data is the P-S-N curve approach. However, the P-S-N curve approach has some issues such as: (1) If there are only a few fatigue test data at a fatigue test stress level, the P-S-N curve approach is not valid due to the small sample size; (2) When the total number of fatigue tests under different stress levels might be larger such as more than 30 even though the number of fatigue tests at the same stress level is small, the P-S-N curve cannot be used to analyze such set of fatigue data; (3) It is difficult to calculate the reliability of a component under a cyclic stress level when the probabilistic distribution function under this stress level is not available in the P-S-N curves. The author has proposed the K-D probabilistic fatigue damage model (K-D model) to overcome those issues. The 6061-T6 10-gauge sheet-type flat fatigue specimen was designed, manufactured, and tested on the Instron 8081 fatigue test machine to verify this K-D model. The fatigue tests were under five different cyclic axial loadings with a total of 195 tests. In this paper, the fatigue test data will be analyzed by the P-S-N curve approach and the K-D model. The systematic comparisons between the P-S-N curve approach and the K-D model have approved and verified that the K-D model can be used to analyze and to describe the fatigue test data under all different fatigue stress levels and can be used to calculate the reliability of a component under any type of cyclic fatigue loading.
Hydrodynamic Coefficients for an Extraterrestrial Submarine
Authors: AlHasni Hani , Thornquist Ona , Islam Shafquat , Garrison Peter , Sahin Iskender
Published: January 2020

An autonomous submarine design was proposed as part of NASA’s NIAC program to explore the hydrocarbon seas of Titan, the Saturnian moon, and study its hydrological cycle. The submarine is to be capable of operating at both the surface and in a deeply-submerged mode. This study aims to complement and compare previous CFD simulations with results obtained using the panel code CMARC. The comparison is of interest as the previous studies included a grid-based viscous code and a particle method using smoothed-particle hydrodynamics. The previous approaches encountered difficulties in obtaining agreeable results as each method has flow regimes suitable for a specific formulation, specifically free-surface flow versus a deeply submerged case. The panel formulation presented here is for the deeply submerged configuration and results match well with other approaches and parametric analyses, particularly when appendages are included in the modeling.
Simulation and Validation of a Two-Phase Pumped Loop Cooling System
Authors: Magee Thomas C. , Hines Kristen M. , Dumesh Mike A. , Meekins Andrew D. , Bridges Michael M.
Published: January 2020

Two-phase refrigerant pumped loop cooling systems have seen wider use in recent years because of higher power density electronics and the need for increased heat transfer capability. However, two-phase systems are difficult to model because they operate in a closed-loop and both liquid and vapor phases exist and change with time throughout the system.

A two-phase “test-bed” system was constructed in order to explore the various operating regimes and limitations of this technology. Additionally, physical results from this test-bed were used to determine if the system performance could be accurately modeled using a commercially available software package such as SINDA/FLUINT. The refrigerant circuit uses R134a as the cooling fluid that is pumped around a complete loop using a positive displacement pump. Heat is added at the evaporator using ceramic heaters on the outside of the housing that boils the fluid, resulting in a liquid/vapor mix in the transport tube. Heat is removed at the condenser which is a commercial flat plate heat exchanger that uses building water for cooling. A closed-loop fluid-thermal model of the test-bed was created in Thermal Desktop®, which is the pre and post-processor for the SINDA/FLUINT analyzer, and compared to several tests conducted on the physical system at varying heat loads. The model successfully predicted the system performance after adjustments to the model for refrigerant mass charge and condenser performance. The maximum difference between the measured evaporator temperature and the modeled temperature was only 6.1°F; which occurred at the highest heat input level (1400 Watts). Explanations for differences between model and test results will be discussed. In particular, modeled system temperatures were found to have a very non-linear sensitivity to the total refrigerant mass charge.