bluuebunny/crossref_metadata_2025 huggingface dataset:
Architectural and ultrastructural features of tessellated calcified cartilage in modern and extinct chondrichthyan fishes
Authors: Maisey John G. , Denton John S. S. , Burrow Carole , Pradel Alan
Published: May 2020

Tessellated calcified cartilage (TCC) is a distinctive kind of biomineralized perichondral tissue found in many modern and extinct chondrichthyans (sharks, rays, chimaeroids and their extinct allies). Customarily, this feature has been treated somewhat superficially in phylogenetic analyses, often as a single “defining” character of a chondrichthyan clade. TCC is actually a complex hard tissue with numerous distinctive attributes, but its use as a character complex for phylogenetic analysis has not yet been optimized. This study attempts to improve this situation by presenting new terminology for certain aspects of tesseral architecture, including single‐monolayered, multiple‐monolayered, polylayered and voussoir tesserae; new histological data, including thin sections of TCC in several Palaeozoic taxa, and new proposals for ways in which various characters and states (many of which are defined here for the first time) could be applied in future phylogenetic analyses of chondrichthyan fishes. It can be concluded that many, but not all, of the unique attributes of modern TCC evolved by the Early Devonian (ca. 400 before present (bp)). The globular calcified cartilage reported in Silurian sinacanthids and the so‐called subtessellated perichondral biomineralization (with irregular and ill‐defined geometries of a layer or layers of calcified cartilage blocks) of certain extinct “acanthodians” (e.g.,Climatius,Ischnacanthus,Cheiracanthus) could represent evolutionary precursors of TCC, which seems to characterize only part of the chondrichthyan total group. It is hypothesized that heavily biomineralized “layer‐cake” TCC in certain Palaeozoic chondrichthyans perhaps served a dual physiological role, as a phosphate sink and in providing increased skeletal density in very large (>7 m) Devonian‐Permian marine sharks such as ctenacanths and as an adaptation to calcium‐deficient environments among Permo‐Carboniferous non‐marine sharks such as xenacanths. By contrast, the equivalent tissue in modern elasmobranchs probably serves only to reinforce regions of cartilage (mostly in the jaws) subjected to high loading. It is also noted that much of the variation observed in tesseral architecture (including localized remodelling), ultrastructure and histology in modern and extinct chondrichthyans is confined to the perichondrally facing cap zone (where Type‐1 collagen matrix predominates in modern TCC), whereas the main body of the tessera (where Type‐2 collagen matrix predominates) exhibits comparatively little evidence of remodelling and histological or structural variation.
Guillain‐Barré syndrome during SARS‐CoV‐2 pandemic: A case report and review of recent literature
Authors: Scheidl Erika , Canseco Daniel Diez , Hadji‐Naumov Aleksandar , Bereznai Benjamin
Published: May 2020

Acute demyelinating inflammatory polyneuropathy (AIDP) is the most common type of Guillain‐Barré syndrome (GBS) in Europe, following several viral and bacterial infections. Data on AIDP‐patients associated with SARS‐CoV‐2 (coronavirus‐2) infection are scarce. We describe the case of a 54‐years‐old Caucasian female patient with typical clinical and electrophysiological manifestations of AIDP, who was reported positive with PCR for SARS‐CoV‐2, 3 weeks prior to onset of the neurological symptoms. She did not experience a preceding fever or respiratory symptoms, but a transient loss of smell and taste. At the admission to our neurological department, a progressive proximally pronounced paraparesis, areflexia, and sensory loss with tingling of all extremities were found, which began 10 days before. The modified Erasmus Giullain‐Barré Syndrome outcome score (mEGOS) was 3/9 at admission and 1/12 at day 7 of hospitalization. The electrophysiological assessment proved a segmental demyelinating polyneuropathy and cerebrospinal fluid examination showed an albuminocytologic dissociation. The neurological symptoms improved significantly during treatment with immunoglobulins. Our case draws attention to the occurrence of GBS also in patients with COVID‐19 (coronavirus disease 2019), who did not experience respiratory or general symptoms. It emphasizes that SARS‐CoV‐2 induces immunological processes, regardless from the lack of prodromic symptoms. However, it is likely that there is a connection between the severity of the respiratory syndrome and further neurological consequences.
Chlorellavulgaris microalgae and/or copper supplementation enhanced feed intake, nutrient digestibility, ruminal fermentation, blood metabolites and lactational performance of Boer goat
Authors: Kholif Ahmed E. , Hamdon Hatem A. , Kassab Ayman Y. , Farahat Eman S. A. , Azzaz Hossam H. , Matloup Osama H. , Mohamed Ashraf G. , Anele Uchenna Y.
Published: May 2020

The associative effects of Chlorella vulgaris microalgae and copper (Cu) supplementation on feed utilisation and lactational performance in goats were evaluated. Thirty‐two lactating Boer goats (34.8 ± 1.7 kg body weight) were used to evaluate the supplementation of C. vulgaris microalgae at 10 g/day (AL treatment), 9 mg of Cu/kg diet (CU treatment) or a mixture of both AL and CU treatments (ALCU treatment) on feed intake, nutrient digestibility, ruminal fermentation, blood metabolites and lactation performance of Boer goat milk yield and composition. Treatments did not affect feed intake; however, AL, ALCU and CU treatments increased (p < .001) nutrient digestibility. Treatment effect on ruminal pH, ammonia‐N or propionate was marginal, but AL and ALCU treatments increased (p < .01) acetate, acetate/propionate ratio and total volatile fatty acids. Treatments increased (p < .001) serum glucose and Cu concentrations. Additionally, ALCU and AL treatments increased (p < .001) daily milk yield, energy corrected milk production, concentrations of ash, energy content, fat, lactose, solids not fat, total solids and milk (feed) efficiency. Conversely, the CU treatment decreased (p < .001) the concentration of all milk components, without affecting milk (feed) efficiency. Additionally, AL and ALCU treatments decreased (p < .05) the concentrations of saturated fatty acids by 2.4% and 4%, respectively, but increased (p < .05) the concentrations of total unsaturated fatty acids (UFAs) by 5.4% and 9.8%, respectively, mono‐UFA by 5.2% and 9.8%, respectively, and conjugated linoleic acid concentrations by 9.3% and 7.4% respectively. In conclusion, supplementation of the diet of lactating Boer goats with C. vulgaris microalgae with or without copper enhanced nutrient digestibility, ruminal fermentation, milk production, milk efficiency and milk nutritive value. Copper supplementation had minimal effects; therefore, its use as a supplement in the presence of C. vulgaris microalgae to the diet of lactating Boer goats is recommended.
Tests for conditional heteroscedasticity of functional data
Authors: Rice Gregory , Wirjanto Tony , Zhao Yuqian
Published: May 2020

Functional data objects derived from high‐frequency financial data often exhibit volatility clustering. Versions of functional generalized autoregressive conditionally heteroscedastic (FGARCH) models have recently been proposed to describe such data, however so far basic diagnostic tests for these models are not available. We propose two portmanteau type tests to measure conditional heteroscedasticity in the squares of asset return curves. A complete asymptotic theory is provided for each test. We also show how such tests can be adapted and applied to model residuals to evaluate adequacy, and inform order selection, of FGARCH models. Simulation results show that both tests have good size and power to detect conditional heteroscedasticity and model mis‐specification in finite samples. In an application, the tests show that intra‐day asset return curves exhibit conditional heteroscedasticity. This conditional heteroscedasticity cannot be explained by the magnitude of inter‐daily returns alone, but it can be adequately modeled by an FGARCH(1,1) model.
Elevated liver stiffness without histological evidence of liver fibrosis in rural Ugandans
Authors: Tibuakuu Martin , Jjingo Caroline , Kirk Gregory Dale , Thomas David Lee , Gray Ronald , Ssempijja Victor , Nalugoda Fred , Serwadda David , Ocama Ponsiano , Opio Christopher Kenneth , Kleiner David Erwin , Quinn Thomas Charles , Reynolds Steven James
Published: May 2020

Liver fibrosis may be assessed noninvasively with transient electrography (TE). Data on the performance of TE for detecting liver fibrosis in sub‐Saharan Africa are limited. We evaluated the diagnostic accuracy of TE by performing liver biopsies on persons with liver fibrosis indicated by TE. We enrolled HIV‐infected and HIV‐uninfected participants with TE scores consistent with at least minimal disease (liver stiffness measurement [LSM]≥7.1 kPa). Biopsies were performed and staged using the Ishak scoring system. A concordant result was defined using accepted thresholds for significant fibrosis by TE (LSM ≥ 9.3 kPa) and liver biopsy (Ishak score ≥ 2). We used modified Poisson regression methods to quantify the univariate and adjusted prevalence risk ratios (PRR) of the association between covariates and the concordance status of TE and liver biopsy in defining the presence of liver fibrosis. Of 131 participants with valid liver biopsy and TE data, only 5 participants (3.8%) had Ishak score ≥ 2 of whom 4 had LSM ≥ 9.3 kPa (sensitivity = 80%); of the 126 (96.2%) with Ishak score < 2, 76 had LSM < 9.3 kPa (specificity = 61%). In multivariable analysis, discordance was associated with female gender (adjPRR = 1.80, 95%CI 1.1‐2.9; P = .019), herbal medicine use (adjPRR 1.64, 95% CI = 1.0‐2.5; P = .022), exposure to lake or river water (adjPRR 2.05, 95% CI = 1.1‐3.7; P = .016), and current smoking (adjPRR 1.72, 95%CI 1.0‐2.9; P = .045). These data suggest that TE among rural Ugandans has low specificity for detection of histologically confirmed liver fibrosis. Caution should be exercised when using this tool to confirm significant liver fibrosis.
Intraspecific responses to climate reveal nonintuitive warming impacts on a widespread thermophilic conifer
Authors: Patsiou Theofania S. , Shestakova Tatiana A. , Klein Tamir , di Matteo Giovanni , Sbay Hassan , Chambel Mª Regina , Zas Rafael , Voltas Jordi
Published: May 2020

Many ecologically important forest trees from dry areas have been insufficiently investigated for their ability to adapt to the challenges posed by climate change, which hampers the implementation of mitigation policies. We analyzed 14 common‐garden experiments across the Mediterranean which studied the widespread thermophilic conifer Pinus halepensis and involved 157 populations categorized into five ecotypes.

Ecotype‐specific tree height responses to climate were applied to projected climate change (2071–2100 ad), to project potential growth patterns both locally and across the species' range.

We found contrasting ecotypic sensitivities to annual precipitation but comparatively uniform responses to mean temperature, while evidence of local adaptation for tree height was limited to mesic ecotypes. We projected intriguing patterns of response range‐wide, implying either height inhibition or stimulation of up to 75%, and deduced that the ecotype currently experiencing more favorable (wetter) conditions will show the largest inhibition. Extensive height reductions can be expected for coastal areas of France, Greece, Spain and northern Africa.

Our findings underline the fact that intraspecific variations in sensitivity to precipitation must be considered when projecting tree height responses of dry forests to future climate. The ecotype‐specific projected performances call for management activities to ensure forest resilience in the Mediterranean through, for example, tailored deployment strategies.
At the crossroads of strigolactones and abscisic acid pathways: A role for miR156
Authors: Brun Guillaume
Published: May 2020

This article comments on: A novel strigolactone‐miR156 module controls stomatal behaviour during drought recovery
Promoting medication adherence from the perspective of adolescent and young adult kidney transplant recipients, parents, and health care professionals: A TAKE‐IT TOO study
Authors: Nguyen Christina , Dew Mary Amanda , Irizarry Taya , McNulty Mary , Rennick Janet , Knäuper Bärbel , Descoteaux Annie , Grenier Audrey , Jeannot Lovemine , Foster Bethany J. , DeVito Dabbs Annette J. ,   all TAKE‐IT TOO Investigators
Published: May 2020

Medication non‐adherence is an important factor limiting allograft survival after kidney transplantation in AYA. Some interventions, including the TAKE‐IT, showed some success in promoting adherence but the potential for scalability and use in routine clinical practice is limited. We applied user‐centered design to gather the perspectives of recipients, parents, and health professionals concerning their needs, challenges, and potential intervention strategies to design an optimal, multi‐component medication adherence intervention. The qualitative study was conducted at four Canadian and three American kidney transplant programs. Separate focus groups for recipients, parents, and health professionals were convened to explore these stakeholders' perspectives. Directed content analysis was employed to identify themes that were shared vs distinct across stakeholders. All stakeholder groups reported challenges related to taking medications on time in the midst of their busy schedules and the demands of transitioning toward independence during adolescence. The stakeholders also made suggestions for the multi‐component behavioral intervention, including an expanded electronic pillbox and companion website, education materials, and customized digitized features to support shared responsibility and communication among recipients, parents, and health professionals. Several suggestions regarding the functionality and features of the potential intervention reported in this early stage will be explored in more depth as the iterative process unfolds. Our approach to actively involve all stakeholders in the process increases the likelihood of designing an adherence intervention that is truly user‐informed and fit for the clinical setting.
Eplet incompatibility in pediatric renal transplantation
Authors: Rãchişan Andreea Liana , Dubois Valerie , Ranchin Bruno , Sellier‐Leclerc Anne‐Laure , Bertholet Thomas Aurelia , Cochat Pierre , Bacchetta Justine
Published: May 2020

Eplet incompatibility appears to be a better predictor of the de novo appearance of DSA post‐Tx than HLA antigen matching in adults. We evaluated the HLA Matchmaker® software (version 2.1) in our pediatric cohort to predict the appearance of DSA post‐Tx. We included 70 pediatric patients (26 girls, 10 living donors, mean age 11.2 ± 3.9 years) after a first R‐Tx (January 2010‐August 2016), without prior immunization, having complete HLA typing (A, B, C, DRB1 and DQB1) and DSA follow‐up for at least one year. The mean of HLA and eplet incompatibilities was 4.7 ± 1.3 and 15.5 ± 6.1, respectively, with a correlation coefficient r2 between these two variables of 0.34 (P < .001). The eplet load was 12.8 ± 5.0 in living donors vs 15.9 ± 6.2 in deceased donors (P = NS), 12.6 ± 6.1 in preemptive R‐Tx (n = 14) vs 16.3 ± 5.9 for non‐preemptive R‐Tx (P = .04). Seven patients (10%) developed DSA during the 3.5 ± 1.2 years post‐Tx. The eplet load was 13.7 ± 5.5 for those who developed DSA vs 15.7 ± 6.1 for the others (P = NS). In our single‐center series of pediatric R‐Tx with good HLA matching and lower eplet load than previously published series, eplet incompatibilities do not predict the development of DSA. The question of the HLA matching requirement and the daily interest of the HLA Matchmaker® software to help select the grafts remain open.
Pediatric kidney transplantation in Egypt: Results of 10‐year single‐center experience
Authors: Fadel Fatina I. , Bazaraa Hafez M. , Badawy Hesham , Morsi Hany A. , Saadi Gamal , Abdel Mawla Mohamed A. , Salem Amr Mohamed , Abd Alazem Eman Abobakr , Helmy Rasha , Fathallah Mohamed Gamal , Ramadan Yasmin , Fahmy Yosra Aboelnaga , Sayed Shaimaa , Eryan Eman Fathy , Atia Fatma Mohammad , ElGhonimy Mohamed , Shoukry Ahmed I. , Shouman Ahmed M. , Ghonima Waleed , Salah Eldin Mohamed , Soaida Sherif M. , Ismail Wesam , Salah Doaa M.
Published: May 2020

Pediatric kidney transplantation is a multidisciplinary therapy that needs special consideration and experience. In this study, we aimed to present CUCH experience; over a 10‐year period, as a specialized center of kidney transplantation in children. We studied 148 transplantations performed at a single center from 2009 to 2018. Pretransplant and follow‐up data were collected and graft/patient survival rates were evaluated. A total of 48 patients developed at least one rejection episode during 688 patient‐years of follow‐up. Infections, recurrence of original disease, and malignancy were the most important encountered medical complications (20%, 2%, and 1.4%, respectively). One‐year patient survival was 94.1%, while graft and patient survival was 91.9%. Graft/patient survival at 5, 7, and 9 years was 90%, 77%, and 58%, respectively. Infections were the main cause (69%) of mortality. Death with a functioning graft and CR were the main causes of graft loss (48% and 33%, respectively). Pediatric kidney transplantation in Egypt is still a challenging yet successful experience. Rejections and infections are the most frequent complications. Short‐term outcomes surpass long‐term ones and graft survival rates are similar to the international standard.
Contemporary Policy Challenges in Protecting the Homeland
Authors: Eller Warren S. , Wandt Adam S.
Published: May 2020

The terrorist attacks of 2001 served as a triggering event for the inception of a policy domain focused on homeland security, and with it came a body of research substantively concentrated on public policy addressing the unique challenges presented in the emerging policy domain. Since naissance, policy issues addressing homeland security have been both disparate and highly salient creating a literature that covers topics ranging from measuring vulnerability of populations to denial of service attacks on medical facilities. This article reviews the literature for a description of what Homeland Security policy is (or is not), where the research in public policy broadly defined has improved knowledge or practice, aspects of the policy domain that require development, and the challenges associated with research in this area. We find that broadly speaking, the most productive areas of inquiry in this domain are those that have the least uncertainty—those that migrated as a mature area of research, those based on objective measures, and those with identifiable origins.
Predictors of caregiver distress among spouses, adult children living with the person with dementia, and adult children not living with the person with dementia
Authors: Wawrziczny Emilie , Duprez Christelle , Antoine Pascal
Published: May 2020

Aim

The caregiving situation differs according to the type of relationship between the patient caregiver, and among dementia caregivers, living with the person with dementia can contribute to caregiver distress. This study aimed to identify the predictors of caregiver distress based on caregiver profile: spouse, adult child living with the person with dementia, and adult child not living with the person with dementia.

Method

In total, 213 caregivers participated in this study. Their responses to questionnaires helped identify the positive and negative implications of the caregiving situation and the level of caregiver distress. The analyses consisted of univariate and multiple linear regression models using a forward method.

Results

Based on the standardized beta scores, the variables that are the most significant in predicting spouse caregiver distress are the impact on health and impact on schedule. The variable that is the most significant in predicting the distress of adult child caregivers living with the person with dementia is the impact on health. The variables that are the most significant in predicting the distress of adult child caregivers not living with the person with dementia are the impact on health, impact on schedule, and impact on finances.

Conclusion

The results make it possible to consider different approaches to providing support, including evaluating the health of all caregivers, giving guidance on accepting help and focusing caregivers' actions on their values for spouse caregivers, providing family mediation for adult child caregivers living with the person with dementia, and offering information and assistance on the available aids for adult child caregivers not living with the person with dementia.
Effect of the side of ovulation on the uterine morphometry, blood flow, progesterone, oestradiol and nitric oxide during spontaneous and induced oestrus in lactating dairy cows
Authors: Abdelnaby Elshymaa A. , Abo El‐Maaty Amal M.
Published: May 2020

This study investigates the changes in endometrial thickness between ipsilateral and contralateral uterine horns, diameter, blood flow area and hormonal concentrations in cows during natural and induced oestrus. In the induced group, six cows received a controlled internal device insert for 7 days. In the normal and induced oestrous group (n = 12), Doppler was performed day after day from day 5 till day 15. Oestradiol, progesterone and nitric oxide metabolites (NOMs) were measured. Results showed that dorsal, ventral and cross‐section diameter of the ipsilateral horn increased during the induced oestrous group to reach a maximum on day 2 than during normal one. The total coloured area in both horns in a normal and induced group was also affected (p < .001), as the total coloured area in the ipsilateral horns, increased in the induced group, reach a maximum on day 2 after ovulation, while in normal it reaches a maximum on day of ovulation. Oestradiol increased during the induced cycle than during the normal one, but progesterone increased during days after ovulation reaches a higher value on day 10 in both groups. Nitric oxide showed two peaks, one on the day 3 and another peak on day 5. Conclusion: The ipsilateral uterine horn different diameters and thickness increased more rapidly in the induced oestrous group than the natural oestrus group. A complete analysis of variations in P4 and E2 concentrations and endometrial thickness suggested that decreases in P4 concentrations were related to an increase in endometrial thickness and that increases in E2 concentrations enhanced these endometrial changes.
Occupational attainment and stratification in China: The interactive effects of social networks and the hukou system
Authors: Li Zhongda , Lin Jianhao , Liu Lu
Published: May 2020

This paper examines the effects of social networks and hukou status on worker’s occupational attainment in China. To identify the potential ranking of different occupations, we consider the use of the stereotype ordered regression model to estimate individual occupational choice. Our results show that social networks play different roles in shaping occupational outcomes for urban and rural workers. In particular, friendship ties significantly improve urban workers’ opportunities in obtaining higher‐ranked occupations; in contrast, kinship ties appear to be more influential for rural migrants, but the effects are limited to the attainment of lower‐ranked occupations. While social contacts from government organizations or state‐owned sectors facilitate urban workers’ attainment of higher‐ranked occupations, similar patterns are not observed among rural workers. We further find that the beneficial effects of social networks or urban hukou identity are stronger for workers who are from less‐developed regions, who work in state‐owned enterprises, or who have a college degree. Decomposition of the wage gap between urban and rural workers suggests that differences in social networks and occupation types, together with hukou discrimination, account for the majority of the current wage inequality.
Assisted breastfeeding technique to improve knowledge, attitude, and practices of mothers with cleft lip‐ and palate‐affected infants: A randomized trial
Authors: Murthy Prashanth Sadashiva , Deshmukh Seema , Murthy Srinivasa
Published: May 2020

Background

Cleft lip and palate is one of the most common developmental anomalies affecting the craniofacial region leading to an array of problems including the inability to feed properly.

Objectives

This study aimed to compare the effectiveness of specially designed audio‐visual module over traditional instructional module in improving the assisted breastfeeding habits.

Methodology

Sixteen patients received training regarding the feeding practices through the traditional instructional method, and 16 subjects received training through audio‐visual module. Infants in both the groups received the standard care. These infants were followed up longitudinally for 6 months. During the follow up period, the growth parameters were recorded monthly. The knowledge, attitude, and practices of the mothers regarding feeding practices were assessed using KAP questionnaire.

Results

There was significant improvement in the knowledge of the mothers from baseline to 6 months, however, the practices indicated that the mothers belonging to the audio‐visual module group showed better understating of the condition and earlier adaptation of the breastfeeding practices. Correspondingly, the growth parameters also showed significant difference.

Conclusion

The custom‐made audio‐visual module would help the mothers adapt better to the stressful situation following the birth of the infant affected with cleft lip and palate.
Fake News Is Real: The Significance and Sources of Disbelief in Mainstream Media in Trump’s America
Authors: Lee Taeku , Hosam Christian
Published: May 2020

Are appeals to discredit mainstream media reporting of political news in the guise of “fake news” merely a diversion from more fundamental threats to democratic politics and policymaking? Or is the emerging belief in “fake news” itself a looming threat? Using data from the Voter Study Group’s panel survey, we examine the relationship between disbelief in mainstream media and a wide range of social attitudes and policy preferences. We find that in December 2016, just after Trump’s election, belief in fake news wields an outsized influence, independent of partisanship, ideology, media consumption, and other established foundations of public opinion. The effects of fake news beliefs are especially pronounced on key elements of Trump’s rhetoric as candidate and as president—hostility toward immigrants, racial and religious minorities, gender equality, perceptions of America’s “greatness,” and even support for democratic norms and institutions itself. We also find some evidence that by January 2019, the belief in fake news has become even more focally associated with Trump. These findings portend the possibility of an emerging exclusionary, populist variant of American conservatism, of which disbelief in media institutions is a key component.
Frequent transfusion and specific HLA‐DRB1 alleles correlate independently with Miltenberger blood group alloimmunization in dialysis patients
Authors: Hung Shih‐Yuan , Hung I‐Hsien , Yang Yu‐Ting , Liou Hung‐Hsiang , Lin Tsun‐Mei
Published: May 2020

Anti‐“Mia” is the most frequent irregular RBC antibody in Taiwan due to high prevalence of Miltenberger antigens. Dialysis patients, a special patient group that needs frequent transfusions of RBCs, may have the greatest risk for developing anti‐“Mia” antibodies. The aim of this study was to investigate the association between specific HLA‐DRB1 alleles and Mi alloimmunization among dialysis patients. A cohort of 267 maintenance dialysis patients who had ever received at least one RBCs transfusion was enrolled. Anti‐“Mia” was identified in patients' serum using the manual polybrene technique and HLA‐DRB1 genotyping was carried out using polymerase chain reaction and sequence‐specific oligonucleotide probe nonradioactive hybridization. Twenty‐one (7.9%) of patients had positive anti‐“Mia” tests and had received significantly more units of RBC transfusions than those without anti‐“Mia” antibodies (11.3 ± 14.5 U vs 4.5 ± 10.1 U, P = .005). DRB1*04, *07, and *09 alleles were also more prevalent in patients with anti‐“Mia” compared to those without Mi III alloimmunization. The multivariate logistic regression analysis showed that the number of RBC transfusions and the presence of DRB1*04, *07, and *09 phenotypes correlated independently with Mi III immunization (Odds ratios [OR] 1.05 (P = .001) for each unit of RBCs transfused; ORs 4.80 (P = .006), 12.29 (P = .005), and 5.42 (P = .003) for presence of DRB1*04, *07, and *09, respectively). This study is the first to demonstrate markedly high prevalence of Mi III alloimmunization in dialysis patients of Taiwan. Extending Mi III matching for RBC transfusions in susceptible dialysis patients may help to reduce the risk of Mi III alloimmunization in this patient population.
Prospective cohort study of child mouthing of faeces and fomites in Dhaka, Bangladesh (CHoBI7 Program)
Authors: Parvin Tahmina , Minhaj Uddin Ismat , Islam Bhuyian Md. Sazzadul , Saxton Ronald , Zohura Fatema , Sultana Marzia , Johura Fatema‐Tuz , Monira Shirajum , Hasan Md. Tasdik , Papri Nowshin , Haque Md. Ahshanul , Biswas Shwapon K. , Sack David A. , Perin Jamie , Alam Munirul , George Christine Marie
Published: May 2020

Objective

To characterise childhood mouthing and handling behaviours and to assess the association between hand‐to‐object and object‐to‐mouth contacts and diarrhoea prevalence in young children in urban Dhaka, Bangladesh.

Methods

A prospective cohort study was conducted among 494 children under 5 years of age in Dhaka, Bangladesh. This study was nested within the randomised controlled trial of the Cholera Hospital‐Based Intervention for 7 Days (CHoBI7) mobile health (mHealth) program. The CHoBI7 mHealth program focuses on promoting handwashing with soap and water treatment to diarrhoea patients and their household members through mobile messages and a single in person visit. Mouthing and handling of faeces and fomites among young children was measured by five‐hour structured observation and caregiver reports. Diarrhoea surveillance data was collected monthly for 12 months.

Results

Fifty five percent of caregivers reported that their child put a visibly dirty fomite (object or soil) in their mouth in the past week. Caregivers reported that 50% of children had mouthed visibly dirty objects, 26% had mouthed dirt, and 2% had mouthed faeces. Forty five percent of children were observed mouthing a visibly dirty fomite during structured observation, 40% of children were observed mouthing a visibly dirty object, 10% were observed mouthing soil, and one child (0.2%) was observed mouthing faeces. Mouthing of visibly dirty fomites was highest for children 12‐18 months of age with 69% of these children having caregiver reports and 54% having observed events. Children with caregiver reports of mouthing faeces had a significantly higher odds of diarrhoea over the subsequent month (Odds Ratio: 4.54; 95% Confidence Interval: 1.06, 19.48).

Conclusion

These findings demonstrate that mouthing of contaminated fomites among young children is frequent in urban environments in Bangladesh, and that mouthing faeces is associated with a significantly higher odds of diarrhoea. Interventions are urgently needed to protect young children from faecal pathogens in their play spaces.
Phosphatidylinositol 3,5‐bisphosphate regulates Ca2+ transport during yeast vacuolar fusion through the Ca2+ATPase Pmc1
Authors: Miner Gregory E. , Sullivan Katherine D. , Zhang Chi , Rivera‐Kohr David , Guo Annie , Hurst Logan R. , Ellis Ez C. , Starr Matthew L. , Jones Brandon C. , Fratti Rutilio A.
Published: May 2020

The transport of Ca2+ across membranes precedes the fusion and fission of various lipid bilayers. Yeast vacuoles under hyperosmotic stress become fragmented through fission events that requires the release of Ca2+ stores through the TRP channel Yvc1. This requires the phosphorylation of phosphatidylinositol‐3‐phosphate (PI3P) by the PI3P‐5‐kinase Fab1 to produce transient PI(3,5)P2 pools. Ca2+ is also released during vacuole fusion upon trans‐SNARE complex assembly, however, its role remains unclear. The effect of PI(3,5)P2 on Ca2+ flux during fusion was independent of Yvc1. Here, we show that while low levels of PI(3,5)P2 were required for Ca2+ uptake into the vacuole, increased concentrations abolished Ca2+ efflux. This was as shown by the addition of exogenous dioctanoyl PI(3,5)P2 or increased endogenous production of by the hyperactive fab1T2250A mutant. In contrast, the lack of PI(3,5)P2 on vacuoles from the kinase dead fab1EEE mutant showed delayed and decreased Ca2+ uptake. The effects of PI(3,5)P2 were linked to the Ca2+ pump Pmc1, as its deletion rendered vacuoles resistant to the effects of excess PI(3,5)P2. Experiments with Verapamil inhibited Ca2+ uptake when added at the start of the assay, while adding it after Ca2+ had been taken up resulted in the rapid expulsion of Ca2+. Vacuoles lacking both Pmc1 and the H+/Ca2+ exchanger Vcx1 lacked the ability to take up Ca2+ and instead expelled it upon the addition of ATP. Together these data suggest that a balance of efflux and uptake compete during the fusion pathway and that the levels of PI(3,5)P2 can modulate which path predominates.
Influence of Viscosity and Non-Linearities in Predicting Motions of a Wind Energy Offshore Platform in Regular Waves
Authors: Ferrandis José del Águila , Bonfiglio Luca , Rodríguez Ricardo Zamora , Chryssostomidis Chryssostomos , Faltinsen Odd Magnus , Triantafyllou Michael
Published: May 2020

Motion predictions of floating bodies in extreme waves represent a challenging problem in naval hydrodynamics. The solution of the seakeeping problem involves the study of complex non-linear wave-body interactions that require large computational costs. For this reason, over the years, many seakeeping models have been formulated in order to predict ship motions using simplified flow theories, usually based on potential flow theories. Neglecting viscous effects in the wave-induced forces might largely underestimate the energy dissipated by the system. This problem is particularly relevant for unconventional floating bodies at resonance. In these operating conditions, the linear assumption is no longer valid, and conventional boundary element methods, based on potential flow, might predict unrealistic large responses if not corrected with empirical viscous damping coefficients. The application considered in this study is an offshore platform to be operated in a wind farm requiring operability even in extreme meteorological conditions. In this paper, we compare heave and pitch response amplitude operators predicted for an offshore platform using three different seakeeping models of increasing complexity, namely, a frequency-domain boundary element method (BEM), a partly nonlinear time domain BEM, and a non-linear viscous model based on the solution of the unsteady Reynolds-averaged Navier–Stokes (URANS) equations. Results are critically compared in terms of accuracy, applicability, and computational costs.
Coolant Jets Blowing Across the Airfoil Stagnation Line to Enhance Film Effectiveness
Authors: Holgate Nicholas E. , Ireland Peter T. , Romero Eduardo
Published: May 2020

A novel airfoil leading edge film cooling design has been investigated, and its performance over conventional alternatives quantified. In conventional designs, the region near the geometric stagnation line is typically between the two most upstream film hole rows, which each emit coolant in the downstream direction on their respective sides of the airfoil. This region is thus relatively starved of coolant flow and adequate cooling is achieved inefficiently with a high density of holes expelling a large amount of coolant in order to dilute the nearby mainstream flow. Drawing inspiration from recent literature on reverse-blowing film cooling holes, several film cooling geometries have been designed and tested with a view to improving upon this situation by blowing coolant from each side of the airfoil geometric stagnation line to the other in a criss-cross pattern. This is found to be capable of producing much higher film effectiveness near the stagnation line than a series of more conventional designs which were also tested, without decreasing downstream film effectiveness. A method is also described for using experimental film effectiveness data to estimate two novel measures of the efficiency of leading edge film coolant usage: the proportion of the mainstream which interacts with leading edge film coolant and the proportion of coolant from the two most upstream film hole rows which reaches the stagnation line.
Flexoelectric Energy Harvesting Using Circular Thin Membranes
Authors: Li Zhaoqi , Deng Qian , Shen Shengping
Published: May 2020

In this work, we propose a circular membrane-based flexoelectric energy harvester. Different from previously reported nanobeams based flexoelectric energy harvesters, for the flexoelectric membrane, the polarization direction around its center is opposite in sign to that far away from the center. To avoid the cancelation of the electric output, electrodes coated to upper and lower surfaces of the flexoelectric membrane are respectively divided into two parts according to the sign of bending curvatures. Based on Hamilton’s principle and Ohm’s law, we obtain governing equations for the circular membrane-based flexoelectric energy harvester. A generalized assumed-modes method is employed for solving the system, so that the performance of the flexoelectric energy harvester can be studied in detail. We analyze the effects of the thickness h, radius r0, and their ratio on the energy harvesting performance. Specifically, we show that, by selecting appropriate h and r0, it is possible to design an energy harvester with both high energy conversion efficiency and low working frequency. At last, through numerical simulations, we further study the optimization ratio for which the electrodes should be divided.
Flutter Instability and Ziegler Destabilization Paradox for Elastic Rods Subject to Non-Holonomic Constraints
Authors: Cazzolli Alessandro , Dal Corso Francesco , Bigoni Davide
Published: May 2020

Two types of non-holonomic constraints (imposing a prescription on velocity) are analyzed, connected to an end of a (visco)elastic rod, straight in its undeformed configuration. The equations governing the nonlinear dynamics are obtained and then linearized near the trivial equilibrium configuration. The two constraints are shown to lead to the same equations governing the linearized dynamics of the Beck (or Pflüger) column in one case and of the Reut column in the other. Although the structural systems are fully conservative (when viscosity is set to zero), they exhibit flutter and divergence instability. In addition, the Ziegler's destabilization paradox is found when dissipation sources are introduced. It follows that these features are proven to be not only a consequence of “unrealistic non-conservative loads” (as often stated in the literature); rather, the models proposed by Beck, Reut, and Ziegler can exactly describe the linearized dynamics of structures subject to non-holonomic constraints, which are made now fully accessible to experiments.
A Review on Nanocomposites. Part 2: Micromachining
Authors: Le Bao , Khaliq Jibran , Huo Dehong , Teng Xiangyu , Shyha Islam
Published: May 2020

Micromachining of nanocomposites is deemed to be a complicated process due to the anisotropic, heterogeneous structure and advanced mechanical properties of these materials associated with the size effects in micromachining. It leads to poorer machinability in terms of high cutting force, low surface quality, and high rate of tool wear. A comprehensive review on mechanical properties of nanocomposites aiming to pointout their effects on micro-machinability has been addressed in part 1. In part 2, the subsequent micro-machining processes are critically discussed based on relevant studies from both experimental and modeling approaches. The main findings and limitations of these micro-machining methods in processing nanocomposites have been highlighted together with future prospects.
Compensation Modeling and Optimization on Contactless Rotary Transformer in Rotary Ultrasonic Machining
Authors: Zhang Jianguo , Long Zhili , Wang Can , Zhao Heng , Li Yangmin
Published: May 2020

Rotary ultrasonic machining (RUM) is an effective solution to cut, grind, or drill the advanced brittle hard materials. Contactless rotary transformer, with the advantages of high-power transmission efficiency and reliability, is a potential structure to transmit electric power in RUM. In this study, an impedance model of rotary ultrasonic holder (RUH) is established to find that there exist deviations for the resonant frequency and impedance between the RUH and the ultrasonic transducer, indicating that without compensation the ultrasonic transducer cannot find precisely its own resonant frequency by sweeping frequency. To match the resonant frequency and impedance, four compensation topologies are compared and the Series-Series (SS) topology is discovered as the most suitable option. The compensated capacitance values are determined by visualized solution from the contour line method. Both simulation (from matlab–simulink) and experimental results validate that with compensation elements, the resonant frequency and impedance can be matched precisely between the RUH and ultrasonic transducer and the output voltage and current are with better dynamic performance. Moreover, with the same input voltage, the received power of ultrasonic transducer with compensation capacitors is 7.4 times than the one without compensation. Results verify that the compensation optimization of contactless rotary transformer can improve the vibration amplitude in RUM.
The Master Sinter Curve and Its Application to Binder Jetting Additive Manufacturing
Authors: Wheat Evan , Shanbhag Gitanjali , Vlasea Mihaela
Published: May 2020

The master sinter curve (MSC) is an empirical model used to predict the density of a part after being sintered. The model is typically applied to components that undergo isotropic shrinkage. Parts manufactured using binder jetting additive manufacturing (BJAM) are known to have nonuniform powder systems and high levels of anisotropy. This work explores the application of the master sinter curve to components made by BJAM. Cylindrical samples were manufactured with the long axis parallel (vertical), perpendicular (horizontal), and 45 deg to the printing direction. A bimodal blend of titanium powder (0–45  µm and 106–150 µm) was used to make samples with consistent green densities (ranging from 47.2% to 52.3%) between the different orientations. Samples were then sintered at heating rates of 1, 3, and 5 °C/min to a maximum of 1400 °C. After sintering, the samples showed significant variation between the different orientations, with vertical samples on average 7.6 ± 2.98% and 4.7 ± 1.20% denser than the horizontal and the 45 deg samples, respectively. The calculated apparent activation energies for sintering were within the same range for all orientations, 200–260 kJ/mol for vertical and 45 deg, and 140–260 kJ/mol for horizontal samples. Validation sinter runs showed that the density prediction errors of the master sinter curves were between 0.9% and 4.3%. This work shows that the master sinter curve can be applied to predict the sintered density of components manufactured by binder jetting additive manufacturing.
Internal Surface Quality Enhancement of Selective Laser Melted Inconel 718 by Abrasive Flow Machining
Authors: Guo Jiang , Song Chuanping , Fu Youzhi , Au Ka Hing , Kum Chun Wai , Goh Min Hao , Ren Tongqun , Huang Rui , Sun Chen-Nan
Published: May 2020

Additive manufacturing (AM) technology enables a new way for fabricating components with complex internal surfaces. Selective laser melting (SLM), being one of the most common AM techniques, is able to fabricate complex geometries with superior material properties. However, due to the poor surface quality, the fabricated internal surfaces cannot meet the specifications for some real applications. To achieve the required internal surface condition, post-polishing process is essential. As one of the most prominent processes for finishing inaccessible surfaces with a wide range of materials, abrasive flow machining (AFM) shows great potential to polish AM internal surfaces. Hence, this paper presents an analytical and experimental study on the internal surface quality improvement of SLM Inconel 718 by AFM, aiming to verify the feasibility of AFM on internal surface quality improvement. The surface evolution process was modeled, and the effects of process parameters on surface and subsurface quality were evaluated. The results show that good surface roughness was obtained at the medium conditions of high viscosity, large particle size, low extrusion pressure, and low temperature. The surface morphology was greatly affected by the medium particle size which showed consistency with the surface evolution model that small abrasive particles are unable to overcome the width and depth of the valleys, resulting in the formation of craters. The partially melt layer was effectively removed, and no subsurface damage was induced.
A Comparison of Weldability, Structure, and Mechanical Properties of CM64 and Tribaloy T-800 Welds for Hard-Facing of Turbine Blades
Authors: Keshavarz Mohsen K. , Gontcharov Alexandre , Lowden Paul , Brochu Mathieu
Published: May 2020

In this study, the weldability, microstructure, and tensile properties of CM64 and Tribaloy T-800 (T800) cobalt-based hard-facing materials were studied. Successful CM64 hard-facing could be achieved at ambient temperature using manual gas tungsten arc welding (GTAW-MA). It was shown that T800 welded at ambient temperature was prone to cold cracking due to a combination of low ductility with high welding stresses that limited the accommodation of residual stresses by plastic deformation within the weld beads. Sound T800 welds of various geometries and sizes were produced on cobalt- and nickel-based X-40 and Haynes 230 superalloys, respectively, using GTAW-MA when preheating above 900 °C was used. Microstructural analyses on the sound CM64 and T800 welds were performed using optical and electron microscopy and X-ray diffraction. The distribution of elements and phases in each alloy was evaluated and revealed the epitaxial dendritic structure with the Cr–W–Si-based phase in the interdendritic region in CM64 welds compared with petal-like and equiaxed hard Mo–Co–Si-based dendrites and fine particles in T800. Tensile testing from room temperature up to 1093 °C was performed on both alloys. T800 welds possessed lower ultimate tensile strengths and elongations in this temperature range when compared with the CM64 alloy. Recommendations for hard-facing of turbine engine components were provided.