bluuebunny/crossref_metadata_2025 huggingface dataset:
Information‐Seeking Behaviors of Dental Practitioners in Three Practice‐Based Research Networks
Authors: Botello‐Harbaum Maria T. , Demko Catherine A. , Curro Frederick A. , Rindal D. Brad , Collie Damon , Gilbert Gregg H. , Hilton Thomas J. , Craig Ronald G. , Wu Juliann , Funkhouser Ellen , Lehman Maryann , McBride Ruth , Thompson Van , Lindblad Anne
Published: June 2020

Research on the information‐seeking behaviors of dental practitioners is scarce. Knowledge of dentists’ informationseeking behaviors should advance the translational gap between clinical dental research and dental practice. A cross‐sectional survey was conducted to examine the self‐reported information‐seeking behaviors of dentists in three dental practice‐based research networks (PBRNs). A total of 950 dentists (65 percent response rate) completed the survey. Dental journals and continuing dental education (CDE) sources used and their influence on practice guidance were assessed. PBRN participation level and years since dental degree were measured. Full‐participant dentists reported reading the Journal of the American Dental Association and General Dentistry more frequently than did their reference counterparts. Printed journals were preferred by most dentists. A lower proportion of full participants obtained their CDE credits at dental meetings compared to partial participants. Experienced dentists read other dental information sources more frequently than did less experienced dentists. Practitioners involved in a PBRN differed in their approaches to accessing information sources. Peer‐reviewed sources were more frequently used by full participants and dentists with fifteen years of experience or more. Dental PBRNs potentially play a significant role in the dissemination of evidence‐based information. This study found that specific educational sources might increase and disseminate knowledge among dentists.
Critical Appraisal‐Based Learning in a Dental College in India: A Randomized Control Study
Authors: Veeraiyan Deepak Nallaswamy , Sekhar Prathap
Published: June 2020

This study examined the effect of critical appraisal exercises on the quality of preclinical tooth preparation skills and the confidence level of undergraduate dental students at a dental college in India. Forty‐two student volunteers were randomly divided into critical appraisal (CA; n=19) and control (C; n=23) groups. Both groups were given conventional lecture and video demonstration; the CA group was also given critical appraisal exercises. Four evaluators assessed the incisor, canine, premolar, and molar preparations made by all students. The mean overall scores (reported as mean±SD) assigned to the CA group by all evaluators were significantly higher (independent t‐test, p<0.05) than the C group for incisor (CA: 6.19±1.47, C: 5.09±1.52), canine (CA: 5.64±1.36, C: 4.50±1.35), premolar (CA: 5.88±1.03, C: 4.88±1.18), and molar (CA: 5.98±1.16, C: 5.20±0.71) teeth. The CA group also demonstrated a significant increase in self‐confidence over that of the C group (repeated measures general linear model F=8.554, p=0.006). In this study, the critical appraisal exercises significantly improved the preclinical incisor, canine, premolar, and molar tooth preparation skills and the confidence level of the undergraduate dental students.
Dental School Vacant Budgeted Faculty Positions, Academic Years 2008–09 to 2010–11
Authors: Garrison Gwen E. , McAllister Dora Elías , Anderson Eugene L. , Valachovic Richard W.
Published: June 2020

The annual turnover of dental school faculty creates a varying number of vacant budgeted positions from year to year. The American Dental Education Association (ADEA) conducts an annual survey to determine the status and characteristics of these vacant faculty positions. The number of vacant budgeted faculty positions in U.S. dental schools increased throughout the 1990s, with a peak of 417 positions in 2005–06. Since that time, there has been a decrease in the number of estimated vacancies, falling to 227 in 2010–11. The 2008–09 to 2010–11 faculty vacancy surveys explored these decreases, along with information relevant to the number and characteristics of dental faculty vacancies, including data on the distribution of full‐time, part‐time, and volunteer faculty, reasons for faculty separations, and sources of new faculty.
Advanced Predoctoral Implant Program at UIC: Description and Qualitative Analysis
Authors: Afshari Fatemeh S. , Yuan Judy Chia‐Chun , Quimby Anastasiya , Harlow Rand , Campbell Stephen D. , Sukotjo Cortino
Published: June 2020

Dental implant education has increasingly become an integral part of predoctoral dental curricula. However, the majority of implant education emphasizes the restorative aspect as opposed to the surgical. The University of Illinois at Chicago College of Dentistry has developed an Advanced Predoctoral Implant Program (APIP) that provides a select group of students the opportunity to place implants for single‐tooth restorations and mandibular overdentures. This article describes the rationale, logistics, experiences, and perspectives of an innovative approach to provide additional learning experiences in the care of patients with partial and complete edentulism using implant‐supported therapies. Student and faculty perspectives on the APIP were ascertained via focus group discussions and a student survey. The qualitative analysis of this study suggests that the select predoctoral dental students highly benefited from this experience and intend to increase their knowledge and skills in implant dentistry through formal education following graduation. Furthermore, the survey indicates that the APIP has had a positive influence on the students’ interest in surgically placing implants in their future dental practice and their confidence level in restoring and surgically placing implants.
Online Cultural Competency Education for Millennial Dental Students
Authors: Evans Lorraine , Hanes Philip J.
Published: June 2020

Teaching cultural competence is now an educational requirement for U.S. dental curricula to meet 2013 accreditation standards. The question now is, given time restrictions, limited resources, and budget constraints faced by the majority of dental schools, how can they provide effective cultural competency education to prepare future dental professionals? An additional concern regarding instruction is the recent focus on techniques to engage Millennial learners since this generation is characterized as technologically savvy with a preference for multimedia and general dislike of traditional lectures. With these issues in mind, Georgia Regents University developed Healthy Perspectives, an online, interactive course in cultural competence designed to engage Millennial students. Both before and after the course, the students were asked to complete a modified version of the Clinical Cultural Competency Questionnaire. Of the eighty‐eight students in the course (eighty‐one first‐year dental students and seven entering radiology students), seventy‐one completed the questionnaire both before and after the course, for an 81 percent response rate. Seventy‐five students also completed the course evaluation. The pre and post questionnaires showed statistically significant gains for students across the four primary areas of self‐awareness, knowledge, attitudes, and skills. Student evaluations of the course were generally positive, particularly regarding content, but somewhat surprisingly their assessment of the interactive components (which were designed to meet generational expectations) was ambivalent.
A Model of Blended Learning in a Preclinical Course in Prosthetic Dentistry
Authors: Reissmann Daniel R. , Sierwald Ira , Berger Florian , Heydecke Guido
Published: June 2020

The aim of this study was to evaluate the use of blending learning that added online tools to traditional learning methods in a preclinical course in prosthetic dentistry at one dental school in Germany. The e‐learning modules were comprised of three main components: fundamental principles, additional information, and learning objective tests. Video recordings of practical demonstrations were prepared and cut into sequences meant to achieve single learning goals. The films were accompanied by background information and, after digital processing, were made available online. Additionally, learning objective tests and learning contents were integrated. Evaluations of 71 of 89 students (response rate: 80%) in the course with the integrated e‐learning content were available for the study. Compared with evaluation results of the previous years, a substantial and statistically significant increase in satisfaction with learning content (from 30% and 34% to 86%, p<0.001) and learning effect (from 65% and 63% to 83%, p<0.05) was observed. Satisfaction ratings stayed on a high level in three subsequent courses with the modules. Qualitative evaluation revealed mostly positive responses, with not a single negative comment regarding the blended learning concept. The results showed that the e‐learning tool was appreciated by the students and suggest that learning objective tests can be successfully implemented in blended learning.
Dental Students’ Ability to Assess Their Performance in a Preclinical Restorative Course: Comparison of Students’ and Faculty Members’ Assessments
Authors: Tuncer Duygu , Arhun Neslihan , Yamanel Kıvanç , Çelik Çiğdem , Dayangaç Berrin
Published: June 2020

Dental education consists of both theoretical and practical learning for students to develop competence in treating patients clinically. When dental students encounter practical courses in their first year as a new educational experience, they must also learn to evaluate themselves. Self‐evaluation is an essential skill to learn for dental professionals to keep increasing their competence over the course of their careers. The aim of this study was to compare the assessment scores of second‐ and third‐year dental students and the faculty in two consecutive preclinical practical exams in restorative dentistry courses in a dental school in Turkey. Faculty‐ and student‐assigned scores were calculated from two consecutive preclinical examinations on tooth restorations performed on both artificial casts and phantom patients. The students were formally instructed on grading procedures for tooth preparations, base and restoration placement, and polishing criteria. After each step, each item was assessed by faculty members, the student, and another student. The results indicated that the initial differences between second‐year students’ assessments of their own preclinical practical ability and that of the faculty decreased among the third‐year students. Self‐evaluation scores did not indicate whether the third‐year students tended to over‐ or underestimate the quality of their own work. However, the second‐year students not only overestimated themselves but thought they were above average. The results point to the need to develop students’ self‐insight with more exercises and practical training.
U.S. Dental School Deans’ Perceptions of the Rising Cost of Dental Education and Borrowing Pressures on Dental Students: Report of Survey Results
Authors: McAllister Dora Elías , Garrison Gwen E. , Feldman Cecile A. , Anderson Eugene L. , Cook Bryan J. , Valachovic Richard W.
Published: June 2020

This report presents findings from a survey of U.S. dental school deans designed to capture their perceptions regarding the rising cost of dental education and its impact on borrowing by dental students to finance their education. The survey included questions about factors influencing the cost of dental education, concerns about dental student borrowing, and financial awareness resources for students. The survey was distributed to the deans of all 63 U.S. dental schools in January 2013; 42 deans responded, for a 67% response rate. The results indicate that, according to the responding deans, new clinical technologies, technology costs, and central university taxes are the main factors that contribute to the increasing cost of dental education. Coupled with reduced state appropriations at public dental schools and declines in private giving at all dental schools, dental school deans face a perplexing set of financial management challenges. Tuition and fees are a primary source of revenue for all dental schools; however, many deans do not have total control over the cost of attending their schools since tuition and fees are often tied to mandates and policies from the parent university and the state legislature. The findings of this study indicate that U.S. dental school deans are aware of and concerned about the impact of increases in tuition and fees on dental student debt and that they are using a variety of strategies to address the growth in dental student borrowing.
Flipping the Classroom: Assessment of Strategies to Promote Student‐Centered, Self‐Directed Learning in a Dental School Course in Pediatric Dentistry
Authors: Bohaty Brenda S. , Redford Gloria J. , Gadbury-Amyot Cynthia C.
Published: June 2020

The aim of this study was to explore student and course director experiences with the redesign of a traditional lecture‐based course into a flipped classroom for teaching didactic content in pediatric dentistry to second‐year dental students. The study assessed student satisfaction, extent of student engagement, overall course grades, and course director satisfaction. The students enrolled in a flipped classroom pediatric dentistry course (spring semester 2014; SP14) were asked to complete pre‐ and post‐course questionnaires to assess their perceptions of active learning, knowledge acquisition, and course satisfaction. The process was repeated with the class enrolled in the same course the following year (SP15). Responses for SP14 and SP15 resulted in an overall response rate of 95% on the pre questionnaire and 84% on the post questionnaire. The results showed that the greatest perceived advantage of the flipped classroom design was the availability and access to online content and course materials. Students reported enhanced learning due to heightened engagement in discussion. The results also showed that students’ overall course grades improved and that the course director was satisfied with the experience, particularly after year two. Many calls have been made for educational strategies that encourage critical thinking instead of passive learning environments. This study provides one example of a course redesign and demonstrates the need for both faculty and student development to ensure success when a flipped classroom methodology is introduced.
Test‐Enhanced Learning in Competence‐Based Predoctoral Orthodontics: A Four‐Year Study
Authors: Freda Nicolas M. , Lipp Mitchell J.
Published: June 2020

Dental educators intend to promote integration of knowledge, skills, and values toward professional competence. Studies report that retrieval, in the form of testing, results in better learning with retention than traditional studying. The aim of this study was to evaluate test‐enhanced experiences on demonstrations of competence in diagnosis and management of malocclusion and skeletal problems. The study participants were all third‐year dental students (2011 N=88, 2012 N=74, 2013 N=91, 2014 N=85) at New York University College of Dentistry. The 2013 and 2014 groups received the test‐enhanced method emphasizing formative assessments with written and dialogic delayed feedback, while the 2011 and 2012 groups received the traditional approach emphasizing lectures and classroom exercises. The students received six two‐hour sessions, spaced one week apart. At the final session, a summative assessment consisting of the same four cases was administered. Students constructed a problem list, treatment objectives, and a treatment plan for each case, scored according to the same criteria. Grades were based on the number of cases without critical errors: A=0 critical errors on four cases, A−=0 critical errors on three cases, B+=0 critical errors on two cases, B=0 critical errors on one case, F=critical errors on four cases. Performance grades were categorized as high quality (B+, A−, A) and low quality (F, B). The results showed that the test‐enhanced groups demonstrated statistically significant benefits at 95% confidence intervals compared to the traditional groups when comparing low‐ and high‐quality grades. These performance trends support the continued use of the test‐enhanced approach.
Association Between Dental Students’ Emotional Intelligence and Academic Performance: A Study at Six Dental Colleges in India
Authors: Kumar Amit , Puranik Manjunath P. , Sowmya K.R.
Published: June 2020

Since the role of emotional intelligence (EI) in achieving academic excellence requires further research, the aims of this cross‐sectional study were to assess EI and its associated factors and to determine any association between EI and academic performance among final‐year dental students in Bengaluru, India. In 2015, 208 dental students from six dental colleges in Bengaluru were invited to participate in the study. Their demographic and lifestyle data were collected, and EI was assessed with the 30‐item Emotional Quotient Self‐Assessment Checklist developed by Sterrett. Academic performance was assessed using grades obtained in the final‐year undergraduate examination. The response rate was 96% (N=200). Overall, 54.5% of the participants had high EI scores (≥120), although only 51 (25.5%) had a high EI score in all the domains (≥20). EI was significantly greater in females than males. Gender, sleep, meeting friends, physical exercise, recreational activities, and academic performance were significantly associated with EI and accounted for 42% variance in hierarchical regression analysis. EI was also positively associated with academic performance. Gender and healthy lifestyle habits were positively associated with EI, which in turn influenced these students’ academic performance. These findings suggest a possible need for attention to developing dental students’ EI.
The evolution of the US family income–schooling relationship and educational selectivity
Authors: Belzil Christian , Hansen Jörgen
Published: June 2020

We estimate a dynamic model of schooling on two cohorts of the National Longitudinal Survey of Youth and find that, contrary to conventional wisdom, the effects of real (as opposed to relative) family income on education have practically vanished between the early 1980s and the early 2000s. After conditioning on a cognitive ability measure (AFQT), family background variables and unobserved heterogeneity (allowed to be correlated with observed characteristics), income effects vary substantially with age and have lost between 30% and 80% of their importance on age‐specific grade progression probabilities. After conditioning on observed and unobserved characteristics, a $300,000 differential in family income generated more than 2 years of education in the early 1980s, but only 1 year in the early 2000s. Put differently, a $70,000 differential raised college participation by 10 percentage points in the early 1980s. In the early 2000s, a $330,000 income differential had the same impact. The effects of AFQT scores have lost about 50% of their magnitude but did not vanish. Over the same period, the relative importance of unobserved heterogeneity has expanded significantly, thereby pointing toward the emergence of a new form of educational selectivity reserving an increasing role to noncognitive abilities and/or preferences and a lesser role to cognitive ability and family income.
A cross‐section average‐based principal components approach for fixed‐T panels
Authors: Westerlund Joakim
Published: June 2020

Because of the increased availability of large panel data sets, common factor models have become very popular. The workhorse of the literature is the principal components (PC) method, which is based on an eigen‐analysis of the sample covariance matrix of the data. Some of its uses are to estimate the factors and their loadings, to determine the number of factors, and to conduct inference when estimated factors are used in panel regression models. The bulk of the underlying theory that justifies these uses is based on the assumption that both the number of time periods, T, and the number of cross‐section units, N, tend to infinity. This is a drawback, because in practice T and N are always finite, which means that the asymptotic approximation can be poor, and there are plenty of simulation results that confirm this. In the current paper, we focus on the typical micro panel where only N is large and T is finite and potentially very small—a scenario that has not received much attention in the PC literature. A version of PC is proposed, henceforth referred to as cross‐section average‐based PC (CPC), whereby the eigen‐analysis is performed on the covariance matrix of the cross‐section averaged data as opposed to on the covariance matrix of the raw data as in original PC. The averaging attenuates the idiosyncratic noise, and this is the reason why in CPC T can be fixed. Mirroring the development in the PC literature, the new method is used to estimate the factors and their average loadings, to determine the number of factors, and to estimate factor‐augmented regressions, leading to a complete CPC‐based toolbox. The relevant theory is established, and is evaluated using Monte Carlo simulations.
Psychotherapists' preferences for television and movies during the early stages of the COVID‐19 pandemic
Authors: Farber Barry A. , Ort Daisy , Mayopoulos Gus
Published: June 2020

This study investigated psychotherapists' media use since the onset of the COVID‐19 pandemic. A total of 186 psychotherapists completed a 15‐item self‐report survey on the movies and TV shows they had watched, and the reasons for their choices, since the outbreak of the COVID‐19 pandemic. Results indicated therapists primarily watched material they described as comedic, distracting, thought‐provoking, and psychologically engaging. In addition, they reported choosing media that appealed to their spouses and/or children. It is theorized that therapists' media selections are reinforcing their regulatory flexibility, allowing them to grapple with the harsh reality of the pandemic while simultaneously providing themselves emotional safety and relief in the form of distancing and distraction.
IGFBP6 regulates vascular smooth muscle cell proliferation and morphology via cyclin E–CDK2
Authors: Wang Zhecun , Qi Yunling , Wang Rui , Wu Weibin , Li Zilun , Wang Mian , Liu Ruiming , Zhang Chunxiang , Li Wen , Wang Shenming
Published: June 2020

Despite the high prevalence of varicose veins, the underlying pathogenesis of this disease remains unclear. The present study aims to explore the role of insulin‐like growth factor binding protein 6 (IGFBP6) in vascular smooth muscle cells (VSMCs). Using a protein array approach, we identified several differentially expressed proteins between varicose great saphenous veins and normal great saphenous veins. Bioinformatic analysis showed that IGFBP6 was closely related to cell proliferation. Further validation confirmed that IGFBP6 was one of the most highly expressed proteins in varicose vein tissue. Knocking down IGFBP6 in VSMCs significantly attenuated cell proliferation and induced the S phase arrest during the cell cycle. Further experiments demonstrated that IGFBP6 knockdown increased cyclin E ubiquitination, which reduced expression of cyclin E and phosphorylation of CDK2. Furthermore, IGFBP6 knockdown arrested centrosome replication, which subsequently influenced VSMC morphology. Ultimately, IGFBP6 was validated to be involved in VSMC proliferation in varicose vein tissues. The present study reveals that IGFBP6 is closely correlated with VSMC biological function and provides unprecedented insights into the underlying pathogenesis of varicose veins.
Prognostic model and nomogram construction based on autophagy signatures in lower grade glioma
Authors: Wang Chunhui , Qiu Jiting , Chen Sarah , Li Ying , Hu Hongkang , Cai Yu , Hou Lijun
Published: June 2020

The median survival time of lower grade glioma (LGG) tumors spans a wide range of 2–10 years and is highly dependent on the molecular characteristics and tumor location. Currently, there is no prognostic predictor for these tumors based on autophagy‐related (ATG) genes. A prognostic risk score model based on the most significant seven ATG genes was established for LGG. These seven genes, including GRID2, FOXO1, MYC, PTK6, IKBKE, BIRC5, and TP73, have been screened as potentially therapeutic targets. The Kaplan–Meier survival curve analyses validated that patients with high or low risk scores had significantly different overall survival. Following the multivariate Cox regression and area under the ROC curve (AUC) analysis, a final prognostic model based on age, World Health Organization grade, 1p19q‐codeletion status, and ATG risk score was performed as an independent prognostic indicator (training set: p = 4.09E−05, AUC = 0.901; validation set‐1: p = .00069, AUC = 0.808; validation set‐2: p = .0376, AUC = 0.830). Subsequently, a prognostic nomogram was constructed for individualized survival prediction. The calibration plots showed excellent predict efficiency between probability and actual overall survival. In this study, we provided several potential biomarkers for further developing potentially therapeutic targets of LGG. We also established a prognostic model and nomogram to improve the clinical glioma management and assist individualized survival prediction.
Immune reconstitution in children following chemotherapy for acute leukemia
Authors: Williams Anthony P. , Bate Jessica , Brooks Rachael , Chisholm Julia , Clarke Stuart C. , Dixon Elizabeth , Faust Saul N. , Galanopoulou Angeliki , Heath Paul T. , Maishman Thomas , Mapstone Susan , Patel Soonie R. , Vora Ajay , Wilding Sam A. , Gray Juliet C.
Published: June 2020

Although survival rates for pediatric acute lymphoblastic leukemia are now excellent, this is at the expense of prolonged chemotherapy regimens. We report the long‐term immune effects in children treated according to the UK Medical Research Council UKALL 2003 protocol. Peripheral blood lymphocyte subsets and immunoglobulin levels were studied in 116 participants, at six time points, during and for 18‐month following treatment, with 30‐39 patients analyzed at each time point.

Total lymphocytes were reduced during maintenance chemotherapy and remained low 18 months following treatment completion. CD4 T cells remained significantly reduced 18 months after treatment, but CD8 cells and natural killer cells recovered to normal values. The fall in naïve B‐cell numbers during maintenance was most marked, but numbers recovered rapidly after cessation of treatment. Memory B cells, particularly nonclass‐switched memory B cells, remained below normal levels 18 months following treatment. All immunoglobulin subclasses were reduced during treatment compared to normal values, with IgM levels most affected.

This study demonstrates that immune reconstitution differs between lymphocyte compartments. Although total B‐cell numbers recover rapidly, disruption of memory/naïve balance persists and T‐cell compartment persist at 18 months. This highlights the impact of modern chemotherapy regimens on immunity, and thus, infectious susceptibility and response to immunization.
Synthesis and in vitro anticancer activity of some novel cyclohepta[b]thiophene‐3‐carboxamides bearing pyrazole moiety
Authors: Al‐Ghorbani Mohammed , Gouda Moustafa A.
Published: June 2020

2‐Aminothiophene 3 was achieved through the one‐pot multicomponent reaction of cycloheptanone, cyanoacetamide, elemental sulfur, and morpholine in ethanol. Diazotization of 2‐aminothiophene 3 with NaNO2/HCl gave the corresponding diazonium salt 4, that combined with the appropriate active methylene components; 5a, 5b, 7, 11, 13, 16, 18, 21, 9, 19, 22a, and 22b in pyridine (AcONa/EtOH) to form the corresponding hydrazones 6a, 6b, 8, 10, 14, 15, 17, 20, 23, 24, 25a, and 25b, respectively. Heating of compound 8 with malononitrile 9 in ethanol gave the thiazole 10. Treatment of compound 10, 25a, and 25b with hydrazine hydrate achieve the pyrazoles 12, 27a, and 27b, respectively. Hydrazinolysis of compound 14 with hydrazine hydrate, followed by condensation of the obtained hydrazide 15 with acetylacetone 19 gave the pyrazole 20. The recently orchestrated thiophenes were assessed for their cytotoxic action. The result revealed that compound 12 indicated comparable and better action towards HePG2, HCT‐116, MCF‐7, and PC3 cancer cell lines than Doxorubicin.
Diagnosis of COVID‐19 pneumonia despite missing detection of viral nucleic acid and initially inconspicuous radiologic findings
Authors: Schiller Martin , Wydra Stephan , Kerl Hans Ulrich , Kick Wolfgang
Published: June 2020

The diagnosis of coronavirus disease 2019 (COVID‐19) is mainly based on a positive severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) polymerase chain reaction (PCR) result. PCR samples are obtained from upper or lower respiratory tract specimens. However, the sensitivity of PCR is known to have some limitations.

We report on a patient who was admitted to our hospital with dyspnea, fever, cough, and history of contact with a SARS‐CoV‐2 infected relative. The initial chest computed tomography (CT) showed only minimal changes and SARS‐CoV‐2 PCR from a nasopharyngeal swab sample was negative. PCR results obtained from further nasopharyngeal swabs, qualified sputum samples, and from a lower respiratory tract specimen also remained negative. At day 13 after admission, a second chest CT showed radiological findings suspicious for viral pneumonia. Finally, serologic results showed high levels of immunoglobulin G and immunoglobulin A antibodies against the S1 domain of the SARS‐CoV‐2 spike protein, and the patient was diagnosed with COVID‐19 pneumonia.
Selectable and Releasable Noncovalent Functionalization of Semiconducting SWCNTs by Biethynyl‐2,5‐bis(dodecoxy)benzene Unit‐Containing Conjugated Copolymers
Authors: Wei Xia , Maimaitiyiming Xieraili
Published: June 2020

A rigid structural unit diethynyl‐2,5‐bis(dodecoxy)benzene (DDB) is proposed to functionalize single‐walled carbon nanotubes (SWCNTs) with the assistance of pyrimidine ring. The effectiveness of conjugated polymer extraction of semiconducting SWCNTs is demonstrated by absorption and Raman spectroscopy. The protonated pyrimidine ring by the trifluoroacetic acid is used to reduce the interaction between polymer and SWCNTs that the bound wrapping polymer can be removed from the sorted SWCNTs, and molecular dynamics simulations of the binding ability of DDB and pyrimidine units to SWCNTs are conducted to further illustrate the strong binding ability of DDB units to SWCNTs. Therefore, this work provides an effective structural and theoretical reference for polymer separation or modification of semiconducting SWCNTs.
Influence of additive materials on the roughness of AISI D2 steel in electrical discharge machining (EDM) environment
Authors: Abbas M.A. , Lajis M.A. , Abbas D.R. , Merzah O.M. , Kadhim M.H. , Shamran A.A.
Published: June 2020

The quality of the machined surface resulted from the electrical discharge machining (EDM) environment is not efficient according to the previous studies. One of the significant problems is the impedance of dielectric fluid, where it is contributing to focusing the plasma channel in a limited area. Hence, this behavior leads to appearing deep craters on the machined zone. The researchers have attempted to enhance the average of surface roughness by employing powder particles or surfactant as the additive materials in the dielectric fluid. Unfortunately, these studies did not present a comparison between these additive materials in this environment. Therefore, the present study aims to compare the performance of the average of surface roughness (Ra) for AISI D2 steel by utilizing Nano chromium powder (NCP) and Span‐20. The present work has proved that the behavior of the average of surface roughness for this steel is dropping at the maximum level of Nano chromium powder concentration and pulse duration as compared to the behavior with the Span‐20. Moreover, the best roughness was produced by this steel with Nano chromium powder at 2 g/L and 20 μs for this powder and the pulse duration.
Criminalizing price‐fixing
Authors: Dnes Antony W. , Swaray Raymond
Published: June 2020

We assess whether recent US Department of Justice (DOJ) price‐fixing cases exhibit characteristics that are associated theoretically with optimal use of criminal law. We take our welfare standard from seminal work on optimal legal design. Optimal legal design recognizes the private and public elements present in all areas of the law. The mixed results show that the characteristics to be expected in criminal cases are not all present in the DOJ cases. Criminal sanctions applied in these collusive antitrust cases do however show significant responsiveness to some of the variables derived from the economic analysis of criminal law.
Heterozygous nonsense ARX mutation in a family highlights the complexity of clinical and molecular diagnosis in case of chromosomal and single gene disorder co‐inheritance
Authors: Traversa Alice , Marchionni Enrica , Giovannetti Agnese , Genovesi Maria L. , Panzironi Noemi , Margiotti Katia , Napoli Giulia , Piceci Sparascio Francesca , De Luca Alessandro , Petrizzelli Francesco , Carella Massimo , Cardona Francesco , Bernardo Silvia , Manganaro Lucia , Mazza Tommaso , Pizzuti Antonio , Caputo Viviana
Published: June 2020

Background

Corpus callosum agenesis (ACC) is one of the most frequent Central Nervous System (CNS) malformations. However, genetics underlying isolated forms is still poorly recognized. Here, we report on two female familial cases with partial ACC. The proband shows isolated partial ACC and a mild neurodevelopmental phenotype. A fetus from a previous interrupted pregnancy exhibited a complex phenotype including partial ACC and the occurrence of a de novo 17q12 microduplication, which was interpreted as probably disease‐causing.

Methods

A trio‐based clinical exome sequencing (CES) was performed.

Results

Clinical exome sequencing data analysis led to identifying a heterozygous nonsense variant (NM_139058.3:c.922G>T; NP_620689.1:p.Glu308Ter) in the aristaless related homeobox gene (ARX) in the proband, with a putative de novo occurrence, producing a hypothetical protein lacking two essential domains. Sanger analysis confirmed the wild‐type status of both parents in different tissues, and disclosed the occurrence of the nonsense variant in the fetus of the interrupted pregnancy, suggesting a formerly unrecognized contribution of the ARX mutation to the fetus' phenotype and gonadal or gonadosomatic mosaicism in one of the parents.

Conclusion

This study describes the phenotype associated with a heterozygous loss of function variant in ARX. Moreover, it highlights the importance of investigating both chromosomal and genetic contributions in cases of complex syndromic phenotypes involving CNS.
New decay rates for Cauchy problem of Timoshenko thermoelastic systems with past history: Cattaneo and Fourier law
Authors: Afilal Mounir , Feng Baowei , Soufyane Abdelaziz
Published: June 2020

In this paper, we investigate the decay properties of the thermoelastic Timoshenko system with past history in the whole space where the thermal effects are given by Cattaneo and Fourier laws. We obtain that both systems, Timoshenko–Fourier and Timoshenko–Cattaneo, have the same rate of decay
and the regularity‐loss‐type property is not present in some cases. Moreover, new stability number χ is introduced, such new number controls the decay rate of the solution with respect to the regularity of the initial data. To prove our results, we use the energy method in Fourier space to build an appropriate Lyapunov functionals that give the desired results.
Solvability of nonlinear integral equations and surjectivity of nonlinear Markov operators
Authors: Mukhamedov Farrukh , Khakimov Otabek , Embong Ahmad Fadillah
Published: June 2020

In the present paper, we consider integral equations, which are associated with nonlinear Markov operators acting on an infinite‐dimensional space. The solvability of these equations is examined by investigating nonlinear Markov operators. Notions of orthogonal preserving and surjective nonlinear Markov operators defined on infinite dimension are introduced, and their relations are studied, which will be used to prove the main results. We show that orthogonal preserving nonlinear Markov operators are not necessarily satisfied surjective property (unlike finite case). Thus, sufficient conditions for the operators to be surjective are described. Using these notions and results, we prove the solvability of Hammerstein equations in terms of surjective nonlinear Markov operators.
Patterns and Potential Drivers of Steelhead Smolt Migration in Southern California
Authors: Booth Michael T.
Published: June 2020

Downstream migration of smolts is a critical aspect of the life history pathway for anadromous salmonids. Timing of downstream migration can vary along latitudinal and climatic gradients. Steelhead Oncorhynchus mykiss occur over a broad range of climate and hydrologic conditions, but relatively little is known about migration timing of smolts in the southern extent of the species’ range. Using a 19-year data set (1994–2014) of smolt arrivals collected in a downstream migrant trap at the Vern Freeman Diversion facility on the Santa Clara River, one of the largest coastal watersheds in southern California, I report patterns of migration and potential environmental drivers determining migration timing. Large sections of the Santa Clara River and the confluences of its perennial tributaries are intermittent except during winter and spring stormflows, limiting migration opportunities. If tributaries were connected, smolts were regularly encountered in the downstream migrant trap between March and May, with rare observations of downstream migrants in January (0.1%) or February (0.3%). Although these migration data are limited by low smolt abundance and sampling efficiency during high-flow events, potential environmental drivers were identified as cues for smolt migration timing in this region. Day length was a consistent predictor of smolt migration, while hydrology was both a constraint and a cue, with migrants only arriving after tributaries had reconnected to the main stem and with many arrivals occurring weeks or months after storm events had passed. Smolt migration was not consistently synchronized with periods when intermittent sections of the main stem were wetted and passable to the ocean. Between 0% and 70% of smolts arrived at the Vern Freeman Diversion after natural flows were likely insufficient for passage to the ocean. Smolt migration is a critical piece of the management puzzle for southern California steelhead, and these data will serve to inform effective management strategies and research needs for the successful recovery of the species.
Voiding conditions, renal and bowel function in a cohort of adults with spina bifida
Authors: Ehrén Ingrid , Lindbo Lena , Gabrielsson Hanna , Bendt Martina , Seiger Åke
Published: June 2020

Aim

To map voiding patterns, degree of continence, use of drugs for voiding disorders, kidney function and surgical interventions but also the bowel function in a near‐total regional cohort of adults with spina bifida aged more than or equal to 18 years.

Methods

All individuals more than or equal to 18 years of age with spina bifida registered at a regional outpatient clinic (n = 219) were invited to participate, of which 196 persons were included. Bladder and bowel function were assessed according to questions used by the Nordic Spinal Cord Injury Registry by structured interviews and questionnaires in combination with review of patient charts including kidney function.

Results

Twenty percent of the patients voided spontaneously. Fifty‐four percent used clean intermittent catherization (CIC) and of these, 14% had also undergone augmentation of the bladder and/or implantation of an artificial sphincter or sling, 23% had undergone major urological surgery, and 3% had an indwelling catheter. Seventeen percent of patients voiding spontaneously or using CIC reported total continence but as many as 36% reported daily leakage. Anticholinergics was the most common drug, used by 21% in the total cohort. About 13% of the patients had a reduced kidney function but only 1.5% had end stage renal failure. Seventy‐three percent had problems emptying the bowel and 18% experienced fecal leakage weekly or even daily.

Conclusion

We found a large variation in problems with bladder and bowel function in this adult group of persons with spina bifida. A structured customized program for follow‐up seems necessary to optimize their health status in these areas.
Functional heterogeneity of PDGFRα (+) cells in spontaneously active urogenital tissues
Authors: Hashitani Hikaru , Mitsui Retsu , Lang Richard
Published: June 2020

Aims

As PDGFRα (+) cells appear not to suppress the excitability of detrusor smooth muscle by generating SK3‐dependent hyperpolarising as proposed in the gastrointestinal tract, we further explored the functional roles of PDGFRα (+) cells in regulating the spontaneous activity of urogenital tissues.

Methods

Using PDGFRα‐eGFP mice, intracellular Ca2+ signaling in PDGFRα (+) cells of the bladder lamina propria, renal pelvis, and seminal vesicle were visualized using Cal‐590 fluorescence. The distribution and SK3 expression of PDGFRα (+) cells were also examined by immunohistochemistry.

Results

In the bladder lamina propria, SK3 (−) PDGFRα (+) cells exhibited spontaneous Ca2+ transients and responded to stimulation of P2Y1 purinoceptors with MRS2365 (100 nM) or adenosine diphosphate (ADP) (100 μM) by developing Ca2+ transients. In the proximal renal pelvis, PDGFRα (+) cells were distributed in the mucosal, muscular and serosal layers but did not express SK3 immunoreactivity. PDGFRα (+) cells in the musculature resembling atypical smooth muscle cells generated spontaneous Ca2+ transients that were partially suppressed upon P2Y1‐stimulation, while vigorously responding to human angiotensin II (100 nM). In the seminal vesicle, PDGFRα (+) cells in the musculature but not mucosa expressed SK3 immunoreactivity. In the mucosa, the P2Y1 stimulation evoked Ca2+ transients in both PDGFRα (+) cells and PDGFRα (−) cells.

Conclusion

PDGFRα (+) cells in spontaneously active urogenital tissues display heterogeneity in terms of their SK3 expression and P2Y1‐induced Ca2+ responses. Muscular PDGFRα (+) cells in the renal pelvis and mucosal PDGFRα (+) cells in the seminal vesicle may generate depolarizing signals to drive smooth muscle cells.
Acute Graft‐versus‐Host Disease: Emerging Insights and Updates into Detection, Prevention, and Treatment
Authors: DiMaggio Elizabeth
Published: June 2020

Acute graft‐versus‐host disease remains a devastating complication following hematopoietic cell transplantation, resulting in increased morbidity and mortality. Vast research efforts continue to refine or develop new means of prediction, assessment, prevention, and treatment of this syndrome. Recent updates in acute graft‐versus‐host disease include more definitive guidance and definitions for its grading and diagnosis. Biomarker use is being incorporated into early stages following hematopoietic cell transplantation to aid in the detection and prediction of long‐term outcomes. New preventive strategies under investigation include the use of vedolizumab or tocilizumab as upfront prophylaxis. Finally, although steroids remain the backbone of therapy once treatment is warranted, the efficacy of several agents including vedolizumab, tocilizumab, ruxolitinib, and α1 antitrypsin are being evaluated as potential therapeutic options.
A proposal for the addressing the needs of the pediatric pulmonary work force
Authors: Gaston Benjamin , Laguna Theresa A. , Noah Terry L. , Hagood James , Voynow Judith , Ferkol Thomas , Hershenson Marc , Boyne Katie , Delecaris Angela , Ross Kristie , Gozal David , Celedón Juan C. , Abman Steven H. , Moore Paul , Davis Stephanie , Cornfield David N. , Murphy Thomas
Published: June 2020

Unprecedented opportunities and daunting difficulties are anticipated in the future of pediatric pulmonary medicine. To address these issues and optimize pediatric pulmonary training, a group of faculty from various institutions met in 2019 and proposed specific, long‐term solutions to the emerging problems in the field. Input on these ideas was then solicited more broadly from faculty with relevant expertise and from recent trainees. This proposal is a synthesis of these ideas. Pediatric pulmonology was among the first pediatric specialties to be grounded deliberately in science, requiring its fellows to demonstrate expertise in scientific inquiry (1). In the future, we will need more training in science, not less. Specifically, the scope of scientific inquiry will need to be broader. The proposal outlined below is designed to help optimize the practices of current providers and to prepare the next generation to be leaders in pediatric care in the future. We are optimistic that this can be accomplished. Our broad objectives are (a) to meet the pediatric subspecialty workforce demand by increasing interest and participation in pediatric pulmonary training; (b) to modernize training to ensure that future pediatric pulmonologists will be prepared clinically and scientifically for the future of the field; (c) to train pediatric pulmonologists who will add value in the future of pediatric healthcare, complemented by advanced practice providers and artificial intelligence systems that are well‐informed to optimize quality healthcare delivery; and (d) to decrease the cost and improve the quality of care provided to children with respiratory diseases.
Analysis of Electric Explosion Performance of Ni/Cu Multilayer Foil
Authors: Ye Qin , Fu Qiubo , Lei Fan , Yang Shuang
Published: June 2020

Multilayer film is widely used in mechanical, optical, electronic, computer, sensor, recording, aerospace and weapon applications. In the thin‐film energy conversion device, it is desirable to use film to convert more energy. This work investigated the electric explosion performance of Ni/Cu multilayer films that were prepared by using the electrodeposition method. The cross‐section SEM image verified the layered structure of Ni/Cu multilayer foil. The metal in the Ni/Cu multilayer film grew in polycrystalline. The temperature of exothermic reaction in the Ni/Cu multilayer started at 1056 °C. We measured the current and voltage curves of foils with different bridge area. The combination of Cu and Ni in multilayer could improve the initial resistance of foil. The deposited energy of Ni/Cu multilayer foil with a bridge area of 0.4×0.4 mm was 105.57 mJ while the bridge area of 0.3×0.3 mm was 93.05 mJ at charging voltage of 3000 V. Compared with Cu foil, Ni/Cu multilayer foil with bridge area of 0.4×0.4 mm burst earlier and deposited 10.5 mJ more energy. As a result, when the modulation cycle of Ni/Cu multilayer film is 200/300 nm, the Ni/Cu multilayer foil with a bridge area of 0.4×0.4 mm has potential application in exploding foil.