bluuebunny/crossref_metadata_2025 huggingface dataset:
Tb3+‐doped transparent BaGdF5 glass‐ceramics scintillator for X‐ray detector
Authors: Zheng Zhigang , Tong Ye , Wei Rongfei , Hu Fangfang , Sun Xinyuan , Guo Hai
Published: December 2019

Commercial Bi4Ge3O12 (BGO) monocrystal scintillator is relatively complicated to produce and too expensive. Therefore, it is desired to look for alternative scintillating materials with simple process, low consumption, large size, and high efficiency. Here, glass‐ceramics (GC) with high volume fraction of crystal phase and high density by increasing the proportion of heavy metal fluorides in the composition were designed. And bulk Tb3+‐doped transparent BaGdF5 glass‐ceramics with 23.3% crystal volume ratio and density of 4.65 g/cm3 have been prepared. The structural, optical, and luminescent properties of precursor glass and GC were systematically explored through series of characterization techniques including X‐ray diffraction (XRD), transmittance spectra, transmission electron microscope (TEM), photoluminescence (PL) spectra, and X‐ray excited luminescence (XEL). After heat treatment, both PL emission and XEL intensity of GC are enhanced because of the movement of Tb3+ ions from the amorphous glass matrix into BaGdF5 nanocrystals, which possess lower phonon energy and better crystal field. The luminescent quantum efficiency of GC reaches 30.7% and the XEL intensity of GC is around 140% of that of the commercial BGO scintillating crystal. Our results demonstrate that BaGdF5:Tb3+ GC may act as efficient scintillator for X‐ray detection.
Geolocation and stable isotopes indicate habitat segregation between sexes in Magellanic penguins during the winter dispersion
Authors: Barrionuevo Melina , Ciancio Javier , Steinfurth Antje , Frere Esteban
Published: December 2019

The Magellanic penguin Spheniscus magellanicus is a top predator and a major consumer of marine resources in the Patagonian Continental Shelf and worldwide. It is the most migratory of the Spheniscus penguins, but until recently, its migration route was only partially known. Our aims with regard to the Magellanic penguin breeding on Isla Quiroga, Argentina, were: 1) to compare the distribution during the winter period between sexes and 2) in case that habitat is segregated, to evaluate possible proximate causes like competitive exclusion and/or habitat specialization. In March 2017 and 2018, prior to migration, we equipped 26 penguins with MK3/4 geolocators, which were recovered in late September/early October. Penguins dispersed northwards up to 29°S and southwards up to 56°S, near the Beagle Channel, being distributed over 2158 ± 50 km of latitudinal range and showing a large‐scale distribution pattern across longitudes in waters within the continental shelf. We found a longitudinal segregation between sexes in their winter grounds, with males closer to the 200‐m isobath and further from the coastline than females. Morphological and physiological differences between sexes might allow males to dive deeper at a lower cost than females, which could result in a more offshore path for males. This spatial segregation was supported by bulk blood stable isotope values and estimated isotopic niche, which differed between males and females at their arrival from winter breeding grounds, but not while penguin breed and behave as central place foragers in the colony. For the first time in this species, we combined two independent tools, geolocation and stable isotope data, and find that sexual segregation in habitat use could potentially generate an optimal winter foraging strategy for both sexes, precluding potential intersex competition for food.
Overcoming the novelty effect in online gamified learning systems: An empirical evaluation of student engagement and performance
Authors: Tsay Crystal Han‐Huei , Kofinas Alexander K. , Trivedi Smita K. , Yang Yang
Published: December 2019

Learners in the higher education context who engage with computer‐based gamified learning systems often experience the novelty effect: a pattern of high activity during the gamified system's introduction followed by a drop in activity a few weeks later, once its novelty has worn off. We applied a two‐tiered motivational, online gamified learning system over 2 years to a total number of 333 students. In a mixed methods research design, we used 3‐year worth of longitudinal data (333 students for the treatment group and 175 in the control group) to assess students' engagement and performance in that period. Quantitative results established that students engaged and performed better in the gamified condition vis‐à‐vis the nongamified. Furthermore, students exhibited higher levels of engagement in the second year compared with the first year of the gamified condition. Our qualitative data suggest that students in the second year of the gamified delivery exhibited sustained engagement, overcoming the novelty effect. Thus, our main contribution is in suggesting ways of making the engagement meaningful and useful for the students, thus sustaining their engagement with computer‐based gamified learning systems and overcoming the novelty effect.
Students' perceived usefulness of computerized percentage‐only vs. descriptive score Reports: Associations with motivation and grades
Authors: Daniels Lia M. , Bulut Okan
Published: December 2019

In computer‐based testing (CBT) environments instructors can provide students with feedback immediately. Commonly, instructors give students their percentage correct without additional descriptive feedback. Our objectives were (a) to compare students' perceived usefulness of a percentage‐only score report vs. a descriptive feedback report in a CBT environment and (b) to test relationships amongst perceived usefulness, motivation, and exam performance. Using a semester‐long repeated measures design embedded into three real examinations, we found that students perceived the descriptive feedback report as more useful than the percentage‐only report. However, there were no relationships amongst the usefulness of the score report and students' motivation or exam scores. Instead, previous performance was the strongest positive predictor of future performance. We discuss the effortful work required to create descriptive feedback reports with their utility and suggest ways instructors may better support students in using descriptive feedback reports when they are implemented.
ELMOD3‐SH2D6 gene fusion as a possible co‐star actor in autism spectrum disorder scenario
Authors: Loi Eleonora , Moi Loredana , Blois Sylvain , Bacchelli Elena , Vega Benedetti Ana Florencia , Cameli Cinzia , Fadda Roberta , Maestrini Elena , Carta Marinella , Doneddu Giuseppe , Zavattari Patrizia
Published: December 2019

Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders characterized by high heritability. It is known that genetic factors contribute to ASD pathogenesis. In particular, copy number variants (CNVs) are involved in ASD susceptibility and can affect gene expression regulation. 2p11.2 microdeletions encompassing ELMOD3, CAPG and SH2D6 genes have been described in four unrelated ASD families. The present study revealed that this microdeletion is responsible for the production of a chimeric transcript generated from the fusion between ELMOD3 and SH2D6. The identified transcript showed significantly higher expression levels in subjects carrying the deletion compared to control subjects, suggesting that it is not subjected to nonsense‐mediated decay and might encode for a chimeric protein. In conclusion, this study suggests the possible involvement of this gene fusion, together with the other previously identified variants, in ASD.
Association between environmental tobacco smoke exposure across the first four years of life and manifestation of externalizing behavior problems in school‐aged children
Authors: Gatzke‐Kopp Lisa , Willoughby Michael T. , Warkentien Siri , Petrie Daniel , Mills‐Koonce Roger , Blair Clancy
Published: December 2019

Background

Extensive literature in human and animal models has documented an association between maternal smoking during pregnancy and externalizing behavior in offspring. It remains unclear; however, the extent to which postnatal environmental smoke exposure is associated with behavioral development, particularly for children whose mothers did not smoke during pregnancy. The present study examined whether magnitude of exposure to environmental smoke across the first four years of life demonstrated a linear association with later externalizing symptoms.

Methods

Exposure was quantified through salivary cotinine measured when children were 6, 15, 24, and 48 months of age, providing a more accurate quantification of realized exposure than can be estimated from parental report of cigarettes smoked. Data were available for n = 1,096 (50% male; 44% African American) children recruited for the Family Life Project, a study of child development in areas of rural poverty.

Results

Analyses indicate a linear association between cotinine and children’s symptoms of hyperactivity and conduct problems. This association remained significant after controlling for family poverty level, parental education, parental history of ADHD, hostility, depression, caregiver IQ, and obstetric complications. Furthermore, this association was unchanged when excluding mothers who smoked during pregnancy from the model.

Conclusions

Findings are consistent with animal models demonstrating an effect of environmental exposure to nicotine on ongoing brain development in regions related to hyperactivity and impulsivity, and highlight the importance of mitigating children’s exposure to environmental smoke, including sources that extend beyond the parents.
Is fecal calprotectin an accurate marker in the management of Crohn's disease?
Authors: Vernia Filippo , Di Ruscio Mirko , Stefanelli Gianpiero , Viscido Angelo , Frieri Giuseppe , Latella Giovanni
Published: December 2019

Although lacking validated cutoff values, fecal calprotectin (FC), besides C‐reactive protein, is considered the standard test for assessing disease activity in Crohn's disease (CD). The aim of the present review is to provide a general overview of the literature addressing the role of FC in the clinical and endoscopic assessment of disease activity in CD, seeking correlations with capsule endoscopy, response to therapy, prediction of relapse, and postoperative recurrence. A systematic search of the literature up to September 2019 was performed using Medline, Embase, and the Cochrane Library. Only papers written in English concerning FC in adult patients affected by CD were included. Pediatric studies, in vitro studies, animal studies, studies on blood/serum samples, and studies analyzing FC in ulcerative colitis or in both CD and ulcerative colitis were excluded. Out of 713 citations, 65 eligible studies were identified. FC showed high accuracy in the assessment of intestinal inflammation and response to therapy, in particular in colonic disease, thus proving a good surrogate marker for these aims. FC is useful in identifying patients at high risk for endoscopic relapse or postoperative recurrence, for optimizing or downstage therapy. Unfortunately, FC performs less well in small bowel CD. FC is an effective fecal marker in the management of CD patients, optimizing the use of endoscopic procedures. Owing to its diagnostic accuracy, FC may represent a cornerstone of the “treat‐to‐target” management strategy of CD patients.
The association between chronotype, food craving and weight gain in pregnant women
Authors: Teixeira G. P. , Balieiro L. C. T. , Gontijo C. A. , Fahmy W. M. , Maia Y. C. P. , Crispim C. A.
Published: December 2019

Background

This cross‐sectional study investigated the association between chronotype, food craving and weight gain in pregnant women.

Methods

In total, 245 pregnant women attending the public health service in Brazil were included. Chronotype was derived from the time of mid‐sleep time on free days, with a further correction for calculated sleep debt, and higher scores on this variable indicate a tendency to eveningness. A Food Craving Questionnaire Trait and State assessment was performed, and weight gain was calculated. Generalised linear models were used to determine the association between the variables under analysis.

Results

Evening types presented higher anticipation of relief from negative states and feelings as a result of eating as a usual behaviour compared to morning (P = 0.013) and non‐evening types (P = 0.028); less intense desire to eat as a sporadic behaviour compared to morning (P = 0.012) and non‐evening types (P = 0.009); and less anticipation of positive reinforcement that may result from eating as a sporadic behaviour than non‐evening types (P = 0.022). We also found a significant association between chronotype score and anticipation of relief from negative states and feelings as a result of eating (P = 0.004); anticipation of positive reinforcement that may result from eating (P = 0.013) as a usual behaviour; weight gain during the early gestational period (P = 0.024); and intense desire to eat (P = 0.045) as a sporadic behaviour.

Conclusions

We conclude that evening chronotype was associated with the food craving trait. Pregnant women who tend to eveningness are more likely to gain weight in the early gestational period.
Identifying Price Reviews by Firms: An Econometric Approach
Authors: HARRIS MARK N. , LE BIHAN HERVÉ , SEVESTRE PATRICK
Published: December 2019

Price reviews are a potentially costly activity. A significant fraction of unchanged prices may stem from firms not reviewing prices, rather than from obstacles to changing prices per se, such as menu costs. In this paper, we disentangle these two causes of price stickiness by estimating an inflated ordered probit model on a panel of French manufacturing firms. The results point to a low frequency of price reviews, suggestive of the relevance of information costs as a determinant of the observed price stickiness. In view of the “inattentive producers” literature, pointing that the source of price rigidity matters, this is suggestive of a large real effect of monetary policy.
Off‐flavors in pond‐grown ictalurid catfish: Causes and management options
Authors: Tucker Craig S. , Schrader Kevin K.
Published: December 2019

Ictalurid catfish grown in ponds often acquire undesirable off‐flavors prior to harvest. Off‐flavors develop when odorous, lipophilic substances in food or water are absorbed across gut or gill epithelium and concentrated in edible tissues. The most common causes of catfish off‐flavors are two nontoxic secondary metabolites of planktonic cyanobacteria: geosmin (causing an earthy off‐flavor) and 2‐methylisoborneol (causing a musty off‐flavor). Off‐flavored fish are unacceptable for processing, and harvest must be postponed until the source of the odorous compound disappears and the compound purges from edible fish tissue. Harvest delays caused by episodes of off‐flavor increase production time, interrupt cash flow, and increase the risk of fish loss. Catfish farmers consider off‐flavor to be one of their most important production‐related problems. This paper reviews the causes of off‐flavor in catfish, pharmacokinetics of uptake and loss of odorous compounds in catfish, seasonality and prevalence of off‐flavors, farm‐ and industry‐level impacts, the ecology of cyanobacteria in catfish ponds, and various strategies for preventing or treating cyanobacterial (and other) off‐flavors. A decision‐making system based on knowledge gained from research is presented as a guide to effective use of the limited tools available to manage off‐flavors.
Revisiting Aquinas on the Passion of Despair
Authors: Bobier Christopher
Published: December 2019

The passion of despair, according to Thomas Aquinas, is an appetitive movement away from a future arduous good that is impossible to attain. Criticism of his account of despair abounds. Nicholas Lombardo argues that despair cannot be proper passion because the appetite cannot move away from a good. Eric D'Arcy and Susan James argue that Aquinas's description of passions as movements casts doubt on his understanding of some passions, including despair. Michael Miller and John Patrick Reid deny that despair can be morally praiseworthy and conducive to action. In this paper, I defend Aquinas's account of the passion of despair from these criticisms.
Pusey and Scripture: Dead End or Fertile Ground?
Authors: Douglas Brian
Published: December 2019

Pusey is often characterised as obscurantist and conservative in his rejection of the higher literary criticism of the Bible in the later part of the nineteenth century. Much of the criticism of Pusey has focused on a limited assessment of Pusey as a scriptural scholar and on unfair psychological analysis. This article examines Pusey's epistemology more deeply and concludes that he had a breadth of vision which commends itself to the modern world as a critique of reason rather than a rejection of reason. Pusey's role as a biblical scholar is reassessed within the broad context of the Oxford Movement.
Effect of noise and light levels on sleep of intensive care unit patients
Authors: Bani Younis Mohammad , Hayajneh Ferial , Alshraideh Jafar A.
Published: December 2019

Background

Previous studies emphasized that the noise and light levels in intensive care units (ICUs) exceeded the recommended levels by the World Health Organization and the Environmental Protection Agency. This might disturb patients' sleep in these units.

Aims and objectives

The aim of this study is to explore the effect of noise and light levels on the perceived quality of sleep (QOS) of patients in ICUs.

Design

A cross‐sectional exploratory correlational design was used.

Methods

The noise and light levels were measured on an hourly basis from 10 pm to 6 am, and their impact on ICU patients' QOS was evaluated.

Results

The overall light level correlation with the overall QOS was statistically significant at an α level of .05, r (101) = − 0.35, P < .001. The Pearson correlation between the overall ICU nocturnal sound level and patients' overall perceived QOS was statistically significant at an α level of .05, r (101) = − 0.42, P < .001.

Conclusion

The noise and light levels in the ICUs in the selected hospitals are higher than the recommended levels. High noise and light levels have a negative correlation with the patients' QOS.

Relevance to clinical practice

High levels of light and sound are associated with poor QOS among ICU patients.
When the paediatric intensive care unit becomes home: A hermeneutic‐phenomenological study
Authors: Frechette Julie , Lavoie‐Tremblay Mélanie , Kilpatrick Kelley , Bitzas Vasiliki
Published: December 2019

Background

Family‐centred care is the dominant model for providing nursing care in paediatrics. Unit layout has been shown to impact nurses' ability to provide family‐centred care. Little is known about the meanings and experiences of paediatric intensive care unit nurses concerning the care they provide to families within their unique physical setting.

Aim

This study examined paediatric intensive care unit nurses' lived experience of caring for families following a major hospital transformation project, which included the construction of a new unit and quality improvement changes.

Study design

A hermeneutic‐phenomenological design was selected to study a paediatric intensive care unit in a large Canadian paediatric teaching hospital.

Methods

Data were collected over a 6‐month period through individual interviews, photographs, participant observation, and document review. The sample consisted of 15 paediatric intensive care unit nurses who experienced the unit both pre‐ and post‐transformation. Data were analysed in an ongoing fashion using the method described by Benner to identify common and divergent meanings.

Results

Despite pride in offering a family‐friendly environment, nurses' practice prejudiced a family focus in favour of patient‐centred care. Nurses in this study negotiated physical and practice spaces with families by interpreting that nurses do not belong in the home‐like patient room and exhibiting gatekeeping comportments.

Conclusion

Although similar nurse comportments have been identified in prior works, no previous studies have identified these as forming a pattern of negotiating spaces with families.

Relevance to clinical practice

This study provides insights into the lived experience of paediatric intensive care unit nurses in relation to family care, which can stimulate reflections at an organizational level about creating environments where nurses and families can both feel at home.
Type‐Maastrichtian gastropod faunas show rapid ecosystem recovery following the Cretaceous–Palaeogene boundary catastrophe
Authors: Vellekoop Johan , Van Tilborgh Kris H. , Van Knippenberg Paul , Jagt John W. M. , Stassen Peter , Goolaerts Stijn , Speijer Robert P.
Published: December 2019

The study of the global mass extinction event at the Cretaceous–Palaeogene (K/Pg) boundary can aid in understanding patterns of selective extinction, and survival and dynamics of ecosystem recovery. Outcrops in the Maastrichtian type area (south‐east Netherlands, north‐east Belgium) comprise a stratigraphically expanded K/Pg boundary succession that offers a unique opportunity to study marine ecosystem recovery within the first few thousand years following the mass extinction event. A quantitative analysis was performed on systematically sampled macrofossils of the topmost Maastrichtian and lowermost Danian strata at the former Ankerpoort‐Curfs quarry (Geulhem), which represent ‘snapshots’ of the latest Cretaceous and earliest Palaeogene marine ecosystems, respectively. Molluscs in particular are diverse and abundant in the studied succession. Regional ecosystem changes across the K/Pg boundary are relatively minor, showing a decline in suspension feeders, accompanied by an ecological shift to endobenthic molluscs. The earliest Paleocene gastropod assemblage retains many ‘Maastrichtian’ features and documents a fauna that temporarily survived into the Danian. The shallow, oligotrophic carbonate platform in this area was inhabited by taxa that were adapted to low nutrient levels and resistant to starvation. As a result, the local taxa were less affected by the short‐lived detrimental conditions related to K/Pg boundary perturbations, such as darkness, cooling, starvation and ocean acidification. This resulted in relatively high survival rates, which enabled rapid recolonization and recovery of marine faunas in the Maastrichtian type area.
Overexpression of a developing xylem cDNA library in transgenic poplar generates high mutation rate specific to wood formation
Authors: Rauschendorfer James , Yordanov Yordan , Dobrev Petre , Vankova Radomira , Sykes Robert , Külheim Carsten , Busov Victor
Published: December 2019

We investigated feasibility of the Full‐length complementary DNA OvereXpression (FOX) system as a mutagenesis approach in poplar, using developing xylem tissue. The main goal was to assess the overall mutation rate and if the system will increase instances of mutants affected in traits linked to the xylem tissue. Indeed, we found a high mutation rate of 17.7%, whereas 80% of all mutants were significantly affected in cellulose, lignin and/or hemicellulose. Cell wall biosynthesis is a major process occurring during xylem development. Enrichment of mutants affected in cell wall composition suggests that the tissue source for the FOX library influenced the occurrence of mutants affected in a trait linked to this tissue. Additionally, we found that FLcDNAs from mutants affected in cell wall composition were homologous to genes known to be involved in cell wall biosynthesis and most recovered FLcDNAs corresponded to genes whose native expression was highest in xylem. We characterized in detail a mutant line with increased diameter. The phenotype was caused by a poplar homolog of LONELY GUY 1 (LOG1), which encodes an enzyme in cytokinin biosynthesis and significantly increased xylem proliferation. The causative role of LOG1 in the observed phenotype was further reaffirmed by elevated cytokinin concentration in the mutant and recapitulation overexpression experiment wherein multiple independent lines phenocopied the original FOX mutant. Our experiments show that the FOX approach can be efficiently used for gene discovery and molecular interrogation of traits specific to woody perennial growth and development.
Deciphering the high‐quality genome sequence of coriander that causes controversial feelings
Authors: Song Xiaoming , Wang Jinpeng , Li Nan , Yu Jigao , Meng Fanbo , Wei Chendan , Liu Chao , Chen Wei , Nie Fulei , Zhang Zhikang , Gong Ke , Li Xinyu , Hu Jingjing , Yang Qihang , Li Yuxian , Li Chunjin , Feng Shuyan , Guo He , Yuan Jiaqing , Pei Qiaoying , Yu Tong , Kang Xi , Zhao Wei , Lei Tianyu , Sun Pengchuan , Wang Li , Ge Weina , Guo Di , Duan Xueqian , Shen Shaoqi , Cui Chunlin , Yu Ying , Xie Yangqin , Zhang Jin , Hou Yue , Wang Jianyu , Wang Jinyu , Li Xiu‐Qing , Paterson Andrew H. , Wang Xiyin
Published: December 2019

Coriander (Coriandrum sativum L. 2n = 2x = 22), a plant from the Apiaceae family, also called cilantro or Chinese parsley, is a globally important crop used as vegetable, spice, fragrance and traditional medicine. Here, we report a high‐quality assembly and analysis of its genome sequence, anchored to 11 chromosomes, with total length of 2118.68 Mb and N50 scaffold length of 160.99 Mb. We found that two whole‐genome duplication events, respectively, dated to ~45–52 and ~54–61 million years ago, were shared by the Apiaceae family after their split from lettuce. Unbalanced gene loss and expression are observed between duplicated copies produced by these two events. Gene retention, expression, metabolomics and comparative genomic analyses of terpene synthase (TPS) gene family, involved in terpenoid biosynthesis pathway contributing to coriander’s special flavour, revealed that tandem duplication contributed to coriander TPS gene family expansion, especially compared to their carrot counterparts. Notably, a TPS gene highly expressed in all 4 tissues and 3 development stages studied is likely a major‐effect gene encoding linalool synthase and myrcene synthase. The present genome sequencing, transcriptome, metabolome and comparative genomic efforts provide valuable insights into the genome evolution and spice trait biology of Apiaceae and other related plants, and facilitated further research into important gene functions and crop improvement.
The study of behavioral ethics within organizations: A special issue introduction
Authors: Mitchell Marie S. , Reynolds Scott J. , Treviño Linda K.
Published: December 2019

Ethics has emerged as one of the most critical issues facing organizations. Given its importance, an extensive literature has evolved to understand the causes and consequences of (un)ethical decision making and behaviors in organizations. To date, much of this research has relied on research methods (e.g., experiments) that emphasize internal validity and control over external validity and generalizability. Although very informative, such studies frequently utilize samples that are not representative of working adults and their designs often fail to capture the contextual complexity that defines the day‐to‐day realities of organizational life. In this light, this special issue ofPersonnel Psychologyencouraged scholars to investigate ethics within organizations and to offer rich theoretical explanations for why ethical failures and successes occur. The articles in this special issue address this important research agenda and make significant contributions to our understanding of ethics in organizations. Our introduction synthesizes these works, provides an overview of issues facing the broader behavioral ethics literature, and discusses areas for future research.
The association between attachment orientations and partner evaluations: An ideal standards perspective
Authors: Karantzas Gery C. , Simpson Jeffry A. , Overall Nickola C. , Campbell Lorne
Published: December 2019

This research examined links between attachment orientations and evaluations of potential and existing relationship partners with respect to ideal standards. In Study 1, attachment anxiety and avoidance predicted the tradeoffs individuals made when choosing between potential mates. In Studies 2 and 3, attachment anxiety and avoidance were associated with ideal partner discrepancies within existing relationships. The findings across the three studies suggest that highly anxious individuals are more likely to use the ideal partner warmth/trustworthiness and status/resources dimensions when evaluating hypothetical and actual romantic partners, whereas highly avoidant individuals are more inclined to use the ideal partner vitality/attractiveness and status/resources dimensions when making partner evaluations. These novel findings are discussed in terms of evolutionary models of mating strategies and evaluations.
Tattoo pigment agglomerates measured in skin biopsies by computerised light microscopy
Authors: Hutton Carlsen Katrina , Larsen Georg , Serup Jørgen
Published: December 2019

Background

Black tattoo reactions are suggested to be foreign body reactions manifested as papulo‐nodular inflammation that is associated with active sarcoidosis.

Aim

To study the morphology of black and red pigment agglomerates in skin biopsies from tattoo reactions, referenced to clinical diagnoses.

Method

Agglomerate count, area, width, height, circumference and circularity were measured in 161 patients by light microscopy (Olympus BX51™); 161 unstained skin biopsies from 64 black tattoo reactions and 97 reactions in red tattoos with allergy. Images (Jenoptic Gryphax RGB camera) were taken through a 40× objective using immersion oil. Computerised analysis of agglomerates was performed using ImageJ software. Studentttest, chi‐square test, Fisher Exact test, ANOVA and Bonferroni tests were applied.

Results

Comparison of black and red pigment agglomerates showed no overall differences in count, area, width, height or circumference. However, in black tattoo reactions, the count of agglomerates was higher in patients with sarcoidosis (P = .009) vs no sarcoidosis. Black agglomerates were more circular shaped as compared to red,P = .023. In red tattoo reactions, agglomerates in patients with allergic cross‐reactivity were slightly more circular (P = .036) vs patients with milder allergy. The count of red agglomerates was lower in patients clinically typed excessive hyperkeratosis (P = .041) compared with other clinical types of allergy.

Conclusion

Patients with reactions in black tattoos associated with sarcoidosis have increased count of pigment agglomerates vs those without associated sarcoidosis indicating that black pigment agglomeration is one among a number of factors triggering sarcoid tattoo complication. Circular shape of agglomerates may code for bioactivity.
Football matches: Decision making in betting
Authors: Chalikias Miltiadis , Kossieri Evangelia , Lalou Panagiota
Published: December 2019

The aim of this paper is to approach the teaching of the Poisson distribution in a friendly and amusing way. It constitutes a common practice to adopt the main probability distributions in order to predict results of sport events and to estimate the win return of betting activities (Chalikias 2009). In particular, by using the Poisson distribution, we can calculate the probability of the final score in a football match, and then we can compare this probability with the values that various betting companies offer. Combining this information with the average of goals for both, it is possible to make a decision as to which betting company is more profitable for the betting players. The case study of the English Premier League is examined.
Study of Convective Heat Transfer in Grinding Applied to Tool Carbide
Authors: Zhang Lei , Brian Rowe W.
Published: December 2019

The grinding temperature is of great importance for the quality and integrity of machined cemented carbide tool. Tool edge surfaces may be damaged by softening or being stressed, hardened, burned, or cracked. Former research on grinding temperature prediction often made assumptions to simplify heat convection due to the grinding fluid. However, these simplifying assumptions can sometimes undermine the mathematical relationships between grinding conditions and surface temperature, particularly in low-temperature grinding where fluid convection is most important. This paper is an attempt to provide an improved comprehensive thermal model for the prediction of contact temperatures and for monitoring and control of thermal damage. Based on previous thermal model research, this paper tackles a key element of the thermal model for temperature prediction. It proposes a convective heat transfer model based on the classic theory of turbulent flow passing a plate. Theoretical predictions from the thermal model of turbulent flow developed in this paper are compared with experimental values. Predictions are further compared with values from a previously published laminar flow model. And it is shown that the new model leads to a significant reduction in predicted temperatures. The results suggest that the thermal model for the turbulent flow provides a reasonable estimate of predicted temperature values within the region of the fluid boiling temperature. The estimates appear to be an improvement compared with the laminar flow thermal model. The turbulent flow thermal model is considered to improve estimates of background contact temperatures in grinding cemented carbide.
Flow and Heat Transfer in Droplets-Film Interactions
Authors: Liang Gangtao , Yu Haibing , Chen Yang , Shen Shengqiang
Published: December 2019

Multi-droplet impact on a thin liquid film covering a heated wall is numerically studied using a three-dimensional model with an implement of a random disturbance subjected to Gaussian distribution. The model can effectively simulate the splashing process after droplets impingement. Results show that simultaneous impact lowers splashing threshold due to cracking of central liquid sheet, while successive impact results in higher splashing threshold for the trailing droplet than the leading one due to radial flow inside the residual film. Single-phase heat transfer coefficient in the impinged region is remarkably higher than the undisturbed film region, caused by flow enhanced convective heat transfer. A heat transfer blind spot situated under the central liquid sheet in simultaneous impact is identified, at which relatively high local temperature is observed and heat is more difficult to be rejected due to flow stagnation there. Cooling of the heated wall in successive impact is mainly achieved by contacting of the trailing droplet with the heated wall, rather than mixing of cold droplets and warm film. This study discusses the effects of Weber number, wall heat flux and droplets horizontal/vertical interval on the heat transfer coefficient.
Electrical Impedance Based Characterization of Wettability During Electrostatic Suppression of the Leidenfrost State
Authors: Ozkan Onur , Bahadur Vaibhav
Published: December 2019

An electric field can suppress the Leidenfrost state by electrostatically attracting liquid to the surface, which results in significantly higher heat transfer. This study highlights and quantifies the statistical nature of wetting during electrostatic suppression via electrical impedance characterization of Leidenfrost pools. Firstly, electrical impedance characterization is used to study the onset of suppression of the Leidenfrost state. Two different threshold voltages are defined and measured. The first threshold voltage corresponds to the onset of transient (intermittent) wetting and the second threshold corresponds to the onset of continuous wetting. The effect of the temperature and the applied AC waveform frequency on the threshold voltages is studied. Next, the wetted area is measured for different temperatures and voltages. The statistical nature of wetting during electrostatic suppression of the Leidenfrost state is characterized. The measured wetting enhancement indicates that heat transfer can be enhanced by an order of magnitude via electrostatic suppression. Together, these results provide an in-depth understanding of electrostatic suppression, and highlight electrical impedance measurements as a powerful diagnostic tool for this field.
A Numerical Investigation of Air/Mist Cooling in a Conjugate, 3-D Gas Turbine Vane With Internal Passage and External Film Cooling
Authors: Abdelmaksoud Ramy , Wang Ting
Published: December 2019

This paper describes a numerical investigation to study the effect of injecting mist (tiny water droplets, micrometers in size) into the cooling airstream to cool down gas turbine vanes. In this study, the conjugate heat transfer method is employed which consists of the simulation of the air/mist fluid flow inside and outside the vanes as well as the heat conduction through the vane body. The complete 3-D vane with internal cooling passages and external film cooling holes on the surface is simulated in a rotational periodic sector. The discrete phase model (DPM) is used to simulate and track the evaporation and movement of the tiny water droplets. The effects of different parameters such as the mist/air ratio (10–20%) and the mist droplets size (20–50μm) on mist cooling enhancement are investigated. The results show that by using a mist/air ratio of 10%, 15%, and 20% with 20 μm droplets size, on the pressure side, a maximum wall temperature reduction of 250 K, 340 K, and 450 K respectively can be achieved. On the suction side, the corresponding maximum wall temperature reductions are 160 K, 260 K, and 360 K, respectively. Using larger droplets of 50μm did not achieve better cooling enhancement because the droplets were rushed far away from the surface by the acceleration through the film cooling holes. Using the uniform droplet size distribution provides noticeably better cooling enhancement in the first 40% of the vane’s height (from the shroud) than the non-uniform droplet size distribution (Rosin-Rammler Distribution) does.
Modeling the Effect of Cooling Vest on Body Thermal Response of People With Paraplegia During Exercise
Authors: Mneimneh Farah , Ghaddar Nesreen , Ghali Kamel , Moussalem Charbel , Omeis Ibrahim
Published: December 2019

Persons with thoracic spinal cord injury (SCI), also named as people with paraplegia (PA), are encouraged to participate in sport activities for sake of improving their quality of life and health. Yet, heat strain is a major consequence of SCI after which the body loses its ability to regulate its temperature. Disruption in body temperature regulation and instability in core temperature (Tcr) endangers the patient health especially when subjected to extreme ambient conditions or high level of physical activity.

Since thermophysiology is disrupted after SCI, using conventional personal cooling methods may not be effective on PA in a way similar to that of able-bodied people (AB). Experimental studies evaluated the effect of phase change material (PCM) and ice cooling vests on thermal response of PA during exercise. Results showed no change in Tcr values for both types of vest during exercise. This study aims at studying the effectiveness of PCM cooling vest for PA during exercise at intensity level of 6.5 MET within 21.1–23.9 °C room temperature and 50% relative humidity.

A multi-segmented bioheat model of PA coupled with PCM cooling vest model (fabric-PCM-PA model) was deployed to predict Tcr values at different design conditions of the vest. Segmental core and skin temperatures profiles and the sensible and latent heat losses were obtained for torso segments to assess the percentage of enhancement in the cooling vest performance. Results showed that Tcr value of the body and Tcr values of the torso segments didn’t change at different design conditions of the vest; yet sensible heat losses were increased for all torso segments and latent heat losses were reduced. Decreases in latent heat losses affected Tsk values at the torso.

Simulations were performed using fabric-PCM model integrated with PA bioheat model applying variation of skin coverage area, melting point of PCM and combination of both designs. An effective design of the vest for PA was found when using PCM packet at 10°C melting point and coverage area about 40% of torso because sensible heat losses were the highest compared to the other design cases of the vest.
Droplet Spreading and Evaporation on Nanoporous Superhydrophilic Surfaces: Effects of Impact Parameters
Authors: McClure Emma R. , Carey Van P.
Published: December 2019

Recent studies have indicated that droplet evaporation heat transfer can be substantially enhanced by fabricating a thin nanoporous superhydrophilic layer on a metal substrate. Earlier investigations have focused on how these surfaces affect low Weber number deposition of droplets and their subsequent evaporation on a horizontal, upward-facing heated surface. This investigation explores the effects of changing impact parameters — specifically how deposition, spreading, and vaporization on nanoporous superhydrophilic surfaces are affected by changing impact velocity and incident angle of the droplet motion relative to the surface. The results of droplet deposition and evaporation experiments are reported here for multiple droplet sizes (2–6 μL), and multiple incident angles (0–45°), and of 8 μL droplets from different drop heights (1.2, 40, and 80 mm). The results indicate that the strong capillary forces that enhance spreading on these surfaces remain dominant in the spreading and vaporization processes even when droplets strike the surface with significant velocity, and when the incident angle is oblique. The results indicate that increasing the Weber number has little effect on droplet evaporation and decreasing the incident deposition angle further enhances spreading and evaporation heat transfer. This paper also explores the implications of these results for spray cooling applications.
Comparison of Model Predictions and Performance Test Data for a Prototype Thermal Energy Storage Module
Authors: Helmns Dre , Carey Van P. , Kumar Navin , Banerjee Debjyoti , Muley Arun , Stoia Michael
Published: December 2019

Although model predictions of thermal energy storage (TES) performance have been explored in several previous investigations, information that allows experimental validation of performance models has been very limited. This is particularly true for high-performance TES designs that facilitate fast input and extraction of energy. In this paper, we present a summary of performance tests of a high-performance TES unit using lithium nitrate trihydrate phase change material (PCM) as a storage medium. Our experimental program also included thorough property determinations and cyclic testing of the PCM. Performance data is presented for complete dual-mode cycles consisting of extraction (melting) followed by charging (freezing). These tests simulate the daylong cyclic operation of a TES unit for asynchronous cooling in a power plant. The model analysis is found to agree very well, within 10%, with the experimental data except for conditions very near the initiation of freezing. Slight deviation from the predicted performance at that time is a consequence of sub-cooling that is required to initiate solidification. The comparisons presented here demonstrate the viability of thermal energy storage for augmentation of power plant air-cooled condensers as well as other potential applications.
Temperature-Dependent Wettability of Water on a Nickel Surface at Pressurized Condition: A Molecular Dynamics Study
Authors: Zeng Dong-Lei , Feng Biao , Song Jia-Wen , Fan Li-Wu
Published: December 2019

Temperature-dependent wettability of water droplets on a metal surface in a pressurized environment is of great theoretical and practical significance. In this paper, molecular dynamic simulation is used to study this problem by relating the temperature-dependent apparent contact angles to the changes in solid-liquid and solid-vapor interfacial free energies and hydrogen bonds in the nano-sized water droplets with increasing the temperature. The temperature range of interest is set from 298 K to 538 K in a 20 K interval under a constant pressure of 7 MPa. The results show that the contact angle in general decreases with raising the temperature and decreasing trend can be divided into two sections with different slopes. The contact angle drops slowly when the temperature is below 458 K as a critical point. Beyond this point, the contact angle shows a much steeper decrease. The difference between solid-vapor and solid-liquid interfacial free energies is found to decrease slightly with temperature. Combining with that the surface tension drops with increasing the temperature, a decreasing trend of the contact angle is expected according to the Young’s equation. As the temperature increases, the number and average energy of the hydrogen bonds both decrease, and the hydrogen bonds tend to aggregate at the bottom of the nano-droplets.
An Investigation on Mechanism of Droplet Generation in High Inertial Gaseous Flow
Authors: Yao Xinyu , Liu Zhenyu , Wu Huiying
Published: December 2019

Droplet generation involving high inertial gas flow in a T-junction microchannel was experimentally and numerically studied in this work. The effect of high inertial flow on the water droplet generation was investigated based on the obtained results. At various gas Reynold (Re) numbers and liquid Capillary (Ca) numbers, the unique flow regime mapping including squeezing, dripping and jetting was observed. It was found that stable aqueous droplets are generated in the squeezing and dripping flow regimes. Visualization experiment shows that the morphology of droplets generated in the water-gas system is different from that in the traditional water-oil system. As the Re number increases or the Ca number decreases, the droplet length decreases. Increasing both Re number and Ca number can increase the detachment frequency. Based on the 3D VOF simulations, the droplet attachment to one of the channel wall during the pinch-off period and the rebound of liquid phase after droplet detachment was observed. Droplet size, detachment time and droplet generation frequency were then analyzed for the droplet generation. The dominant detachment mechanism during the whole droplet generation process was also discussed in this work.
Effect of Twist Ratio on Heat Transfer Enhancement by Swirl Impingement
Authors: Ramakrishnan Kishore Ranganath , Madhavan Srivatsan , Singh Prashant , Ekkad Srinath V.
Published: December 2019

Steady state experimental work has been carried out to compare a conventional single jet of diameter 12.7mm with a swirling impinging jet. In this study swirl inserts with three different twist ratios 3, 4.5 and 6 were used to induce the swirling motion to the working fluid. The Reynolds number based on conventional impinging jet’s diameter is varied from 10000 to 16000. It is observed that with increase in twist ratio, the average heat transfer enhancement is reduced. However, with higher twist ratios more uniform distribution of heat transfer enhancement is observed.