bluuebunny/crossref_metadata_2025 huggingface dataset:
Serum Dihydrotestosterone and Testosterone Concentrations in Human Immunodeficiency Virus‐Infected Men With and Without Weight Loss
Authors: ARVER STEFAN , SINHA‐HIKIM INDRANI , BEALL GILDON , GUERRERO MARIO , SHEN RUOQING , BHASIN SHALENDER
Published: January 2023

ABSTRACT: Weight loss is an important determinant of disease outcome in human immunodeficiency virus (HIV)‐infected men. Others have suggested that a defect in dihydrotestosterone (DHT) generation contributes to weight loss in HIV‐infected men. To determine whether DHT levels correlate with weight loss independently of changes in testosterone levels, we prospectively measured serum total‐ and free‐testosterone and DHT levels in 148 consecutive HIV‐infected men and 42 healthy men. Thirty‐one percent of HIV‐infected men had serum testosterone levels less than 275 ng/dL, the lower limit of the normal male range; of these, 81% had normal or low LH and FSH levels (hypogonadotropic), and 19% had elevated LH and FSH levels (hypergonadotropic). Overall, serum testosterone, free‐testosterone, and DHT levels were lower in HIV‐infected men than in healthy men, but serum DHT‐to‐testosterone ratios were not significantly different between the two groups. Serum total‐ and free‐testosterone levels were lower in HIV‐infected men who had lost 5 lb or more of weight in the preceding 12 months than in those who had not lost any weight. Serum DHT levels and DHT‐to‐testosterone ratios did not differ between those who had lost weight and those who had not. Serum testosterone and free‐testosterone levels, but not DHT levels, correlated with weight change and with Karnofsky performance status. We also performed a retrospective analysis of data from a previous study in which HIV‐infected men with serum testosterone levels less than 400 ng/dL had been treated with placebo or testosterone patches designed to nominally release 5 mg testosterone over 24 hours. Serum testosterone‐to‐DHT ratios did not change after testosterone treatment. Changes in fat‐free mass were correlated with changes in both serum testosterone (r = 0.42, P = 0.018) and DHT (r = 0.35, P = 0.049) levels. Serum total‐ testosterone and DHT levels were highly correlated with one another, and when the change in serum testosterone was taken into account, serum DHT levels no longer showed a significant correlation with change in fat‐free mass. We conclude that DHT levels are lower in HIV‐infected men than in healthy men but that neither DHT levels nor DHT‐to‐testosterone ratios correlate with weight loss. During testosterone treatment, serum DHT levels increase proportionately, but the increments in serum testosterone correlate with the change in fat‐free mass. Our data do not support the hypothesis that a defect in DHT generation contributes to weight loss in HIV‐infected men independently of changes in testosterone levels; it is possible that such a defect might exist in HIV‐infected men with more severe weight loss.
Construction and Preliminary Characterization of a Series of Mouse and Rat Testis cDNA Libraries
Authors: MCCARREY JOHN R. , o'BRIEN DEBORAH A. , SKINNER MICHAEL K.
Published: January 2023

ABSTRACT:We have constructed a series of 23 cDNA libraries from mouse and rat testicular cells. These include libraries made from whole, intact adult testes; seminiferous tubule cells from adult testes; combined populations of primary spermatocytes from 18‐day‐old mouse testes; and isolated populations of primitive type A spermatogonia, type A spermatogonia, type B spermatogonia, preleptotene spermatocytes, leptotene plus zygotene spermatocytes, juvenile pachytene spermatocytes, adult pachytene spermatocytes, round spermatids, Sertoli cells from 6‐, 8‐, 17‐, and 18–20‐day‐old mice, and peritubular cells from 18–20 day old mice, all recovered from outbred white Swiss (CD‐1) mice. We also constructed libraries from whole adult testes from five other lines of mice: C57 BI6/J, C3 HEB, BDF‐1, Balb/c, and 129 Sv. Finally, there are two libraries made from populations of Sertoli cells and peritubular cells isolated from testes of 20‐day‐old Sprague‐Dawley rats. Enzymatic dissociation, followed by gradient separation or plating/lysing techniques, was used to prepare populations of specific cell types in purities of 85–98%. cDNAs were synthesized from poly A+ mRNA primed with oligo dT and unidirectionally cloned into the lambda Uni‐Zap XR expression vector from Stratagene. Primary titers ranged from 2.1 ± 105 to 2.9 × 108plaque‐forming units, and insert sizes averaged 1.0–1.2 kb. These libraries have been amplified once and submitted to the American Type Culture Collection (ATCC) for distribution to interested investigators. ATCC accession numbers are provided.
Coping and sleep quality in youth: An Experience Sampling study
Authors: Hagemann Noëmi , Kirtley Olivia J. , Lafit Ginette , Vancampfort Davy , Wampers Martien , Decoster Jeroen , Derom Catherine , Gülöksüz Sinan , De Hert Marc , Jacobs Nele , Menne‐Lothmann Claudia , Rutten Bart P. F. , Thiery Evert , van Os Jim , van Winkel Ruud , Wichers Marieke , Myin‐Germeys Inez
Published: January 2023

Introduction

Sleep quality is closely linked with mental health. Two factors that influence sleep are coping style and locus of control, yet these have not been investigated in daily life. In this study, we examined associations between coping styles and sleep quality in daily life and the potential mediating effect of daily locus of control in a sample of youth, a group particularly vulnerable to developing psychopathology.

Methods

Three hundred and seventy‐nine youths from the TwinssCan study participated in an Experience Sampling study, assessing sleep quality as well as state locus of control over the most negative event from the previous day. Participants also completed the Utrecht Coping List, which assessed engagement, disengagement, and emotion‐focused coping.

Results

Disengagement, “passive reaction,” and emotion‐focused coping were associated with lower daily sleep quality. State locus of control did not mediate any effects of coping styles on quality of sleep.

Conclusions

Disengagement, “passive reaction,” and emotion‐focused coping were associated with decreased sleep quality during several consecutive days, which may put youths at risk for developing future insomnia, and strain their mental well‐being over time. Thus, there may be value in asking about coping when a young individual presents with sleep problems; however, impaired coping when sleeping poorly should also be considered.
The landscape of endodontic education research area: A bibliometric analysis
Authors: Fu Di , Yao Lin , Zhu Hualing , Yan Yujia , Ji Mengzhen , Li Yanyao , Chi Yaqi , Wang Ye , Liao Ga , Zou Ling
Published: January 2023

Objectives

Educational research is essential for rationalizing curriculum design, improving evaluation systems, and updating teaching content. This bibliometric study aimed at analyzing the characteristics of publications relevant to endodontic education, thus forming a comprehensive scope of this research area.

Methods

The search was conducted in the Web of Science Core Collection database in May 2022. Knowledge units of the included publications, such as year of publication, journal, country/institution/author, keywords, and highly cited articles/references, were analyzed.

Results

The United States ranked first in the number of articles with a total of 17 articles. The majority of included articles were published in Journal of Dental Education (n = 25), International Endodontic Journal (n = 21), and European Journal of Dental Education (n = 14). The top 3 most frequent keywords were Endodontics, Education, and Root canal treatment. The main topic in endodontic education were curriculum, preclinical education, educational technology, and continuing education.

Conclusion

Forming a full scope of the endodontic research area, this bibliomertic
analysis can help mine the hot topic, predict the frontiers in the field and provide the data necessary to determine the direction of research, rationalize resource allocation, and formulate policy.
UK and Spanish stranger sexual offenders crime scene behaviours and previous convictions: A cross‐cultural comparison
Authors: Almond Louise , Rainbow Lee , Ramos Romero Manuel , Giles Susan , McManus Michelle , Nikolajeva Anastasia
Published: January 2023

International comparisons of previous convictions (PC) and crime scene behaviours (CSB) of stranger sexual offences can inform offender profiling strategies; especially the degree to which pragmatic models cross validate across countries. The present study compared PC and CSB of 474 UK and 418 Spanish cases. CSB and PC were analysed using Chi‐square. UK stranger sexual offenders displayed a higher proportion of all CSB analysed. UK offenders also had a significantly higher proportion of PC with the exception of violence offences. There were no significant differences in sexual pre‐convictions. In both the UK and Spain the CSB ‘reference to the police’ was significantly association with the PC ‘Criminal damage’ no other similar significant associations were found. Explanations for these findings include differences between the countries in regards to: legislation, crime recording processes, data coding processes, with additional consideration of any cultural, environmental and contextual factors.
The association of astrogliosis and microglial activation with aging and Alzheimer's disease pathology in the chimpanzee brain
Authors: Edler Melissa K. , Munger Emily L. , Maycon Hannah , Hopkins William D. , Hof Patrick R. , Sherwood Chet C. , Raghanti Mary Ann
Published: January 2023

Aging and neurodegenerative disorders, such as Alzheimer's disease (AD), trigger an immune response known as glial activation in the brain. Recent evidence indicates species differences in inflammatory responses to AD pathology, highlighting the need for additional comparative studies to further understand human‐specific neuropathologies. In the present study, we report on the occurrence of astrogliosis, microglial activation, and their relationship with age and AD‐like pathology in a cohort of male and female chimpanzees (Pan troglodytes). Chimpanzees with severe astrogliosis exhibited widespread upregulation of hypertrophic astrocytes immunoreactive for glial fibrillary acidic protein (GFAP) throughout all layers of the dorsolateral prefrontal cortex and a loss of the interlaminar palisade. In addition, extreme astrogliosis was associated with increased astrocyte density in the absence of significant microglial activation and AD lesions. A shift from decreased resting to increased phagocytotic microglia occurred with aging, although proliferation was absent and no changes in astrogliosis was observed. Vascular amyloid correlated with decreased astrocyte and microglia densities, while tau lesions were associated with morphological changes in microglia and greater total glia density and glia: neuron ratio. These results further our understanding of inflammatory processes within the chimpanzee brain and provide comparative data to improve our understanding of human aging and neuropathological processes.
Development and Internal Validation of a Prediction Model for Difficult Laryngoscopy Using Ultrasound‐Derived Factor in Comatose Patients
Authors: Li Yueying , Li Jingye , Zhong Liping , Zeng Zhiwen
Published: January 2023

Objectives

The distance from skin to the hyoid bone (DSHB) and skin to the anterior commissure of vocal cords (DSAC) are reliable parameters for pre‐operative airway ultrasound assessment in awake patients and can be assessed in comatose patients. This study aimed to inspect its feasibility and accuracy in predicting difficult laryngoscopy for comatose patients.

Methods

A prospective cohort study included patients with a Glasgow Coma Scale (GCS) of ≤8 who underwent emergency tracheal intubation between November 2019 and August 2020. The outcome was difficult laryngoscopy and classified according to the Cormack–Lehane grading.

Results

A total of 151 patients were included in the study. Fifty‐two (34.4%) patients were categorized as having difficult laryngoscopy. The DSHB add DSAC (hereinafter referred to as the “DSBAC”) was superior to either parameter alone in the predictive performance, and the optimal cut‐off value was 1.90. To optimize the predictive value, DSBAC (adjusted odds ratio [OR]: 7.76; 95% confidence interval [CI]: 2.88–20.94; P < .001), GCS (adjusted OR: 1.39; 95% CI: 3.93–26.28; P = .039), mandibular retraction (adjusted OR: 8.20; 95% CI: 1.92–35.09; P = .005) and edentulous (adjusted OR: 4.23; 95% CI: 1.40–12.80; P = .011) were included in a multivariable model and constructed a nomogram. Discrimination and calibration statistics were satisfactory, with C‐index above 0.80 from both model development and internal validation.

Conclusions

Ultrasound‐derived factor, DSBAC, can be easily assessed and help predict difficult laryngoscopy among comatose patients. A simple nomogram including only four clinical items exhibited excellent discrimination performance and was useful when comatose patients underwent emergency tracheal intubation.
The relationship between learning orientation and new product development capability
Authors: Moreno Espinoza Paola Andrea , Sparano Martins Tomas , Gomes Paulo Morilha Lanzarini
Published: January 2023

The objective of this paper is to analyze the mediating effect of new product development capability on the relationship between learning orientation and financial performance. The research was applied in SMEs that belong to the Personal Hygiene and Cosmetic Industry in Brazil. There are 226 cases in the sample and the method used to test the relations between the hypotheses was the Structural Equation Modeling. The results showed us that learning orientation positively influences financial performance; there is a significant positive relationship between learning orientation and new product development capability; new product development capability has a positive influence on the financial performance; and there is a partial mediating effect of the new product development capability on the relationship between learning orientation and financial performance.
Hearing health care access for adult cochlear implant candidates and recipients: Travel time and socioeconomic status
Authors: Davis Amanda G. , Hicks Kelli L. , Dillon Margaret T. , Overton Andrea B. , Roth Noelle , Richter Margaret E. , Dedmon Matthew M.
Published: January 2023

Objectives

Access to cochlear implantation may be negatively influenced by extended travel time to a cochlear implant (CI) center or lower socioeconomic status (SES) for the individual. There is a critical need to understand the influence of these variables on patient appointment attendance for candidacy evaluations, and CI recipients' adherence to post‐activation follow‐up recommendations that support optimal outcomes.

Methods

A retrospective chart review of adult patients referred to a CI center in North Carolina for initial cochlear implantation candidacy evaluation between April 2017 and July 2019 was conducted. Demographic and audiologic data were collected for each patient. Travel time was determined using geocoding. SES was proxied using ZCTA‐level Social Deprivation Index (SDI) information. Independent samples t tests compared variables between those who did and did not attend the candidacy evaluation. Pearson correlations assessed the association of these variables and the duration of time between initial CI activation and return for first follow‐up visit.

Results

Three hundred and ninety patients met the inclusion criteria. There was a statistically significant difference between SDI of those who attended their candidacy evaluation versus those who did not. Age at referral or travel time did not show statistical significance between these two groups. There was no significant correlation with age at referral, travel time, or SDI with the duration of time (days) between initial activation and the 1‐month follow‐up.

Conclusions

Our findings suggest that SES may influence a patient's ability to attend a cochlear implantation candidacy evaluation appointment and may further impact the decision to pursue cochlear implantation.

Level of evidence: 4 – Case Series.
Aldehyde dehydrogenase in solid tumors and other diseases: Potential biomarkers and therapeutic targets
Authors: Xia Jie , Li Siqin , Liu Suling , Zhang Lixing
Published: January 2023

The family of aldehyde dehydrogenases (ALDHs) contains 19 isozymes and is involved in the oxidation of endogenous and exogenous aldehydes to carboxylic acids, which contributes to cellular and tissue homeostasis. ALDHs play essential parts in detoxification, biosynthesis, and antioxidants, which are of important value for cell proliferation, differentiation, and survival in normal body tissues. However, ALDHs are frequently dysregulated and associated with various diseases like Alzheimer's disease, Parkinson's disease, and especially solid tumors. Notably, the involvement of the ALDHs in tumor progression is responsible for the maintenance of the stem‐cell‐like phenotype, triggering rapid and aggressive clinical progressions. ALDHs have captured increasing attention as biomarkers for disease diagnosis and prognosis. Nevertheless, these require further longitudinal clinical studies in large populations for broad application. This review summarizes our current knowledge regarding ALDHs as potential biomarkers in tumors and several non‐tumor diseases, as well as recent advances in our understanding of the functions and underlying molecular mechanisms of ALDHs in disease development. Finally, we discuss the therapeutic potential of ALDHs in diseases, especially in tumor therapy with an emphasis on their clinical implications.
Intellectual property rights policy and foreign direct investment: A quasi‐natural experiment from China
Authors: Qian Xinlei , Sun Minghao , Pan Minjie , Zou Weiyong , Li Guoxiang
Published: January 2023

Over the past 40 years of reform and opening up, China has attracted a large number of foreign investment. However, because of China's weak intellectual property protection environment, it is difficult to protect the intellectual assets of transnational enterprises, which will affect their investment decisions to some extent. In order to optimize the intellectual property system and improve the intellectual property environment, national intellectual property demonstration city policy was proposed in 2012 to improve the institutional environment. To explore the impact of national intellectual property demonstration city policy on foreign capital inflow, we explore the relationship between national intellectual property demonstration city and foreign direct investment (FDI) using the multi‐period differences‐in‐differences (DID) method based on city panel data of China from 2003 to 2019. Results shows the following: (1) Compared with non‐demonstration cities, national intellectual property demonstration cities are profit to FDI promotion. If a city is rated as a national intellectual property demonstration city, local FDI will increase by 5% on average. After a series of robustness tests, the conclusion is still tenable. (2) We find that the national intellectual property demonstration city policy has obvious urban heterogeneity. The effect of national intellectual property demonstration city policy on the increase in FDI is more significant in central cities, western cities, and key cities. (3) The mechanism test shows that national intellectual property demonstration city policies have a positive effect on FDI through increasing the government's strategic expenditure on intellectual property, improving urban technology innovation capacity, optimizing human capital structure, and promoting the marketization of cities. Therefore, China should continue to implement the policy of national intellectual property demonstration city, especially increasing the number of national intellectual property demonstration city in key cities, central cities, and western cities. On the one hand, these findings can help government evaluate the attractiveness of demonstration cities for FDI. On the other hand, it also provides relevant policy enlightenment for the Chinese government to select appropriate demonstration cities and further refine and implement the national intellectual property demonstration city policies.
Preoperative estimation of vertical profunda artery perforator flap weight using computed tomography angiography for breast reconstruction
Authors: Matsumine Hajime , Shimizu Haruka , Niimi Yosuke
Published: January 2023

Background

The vertical profunda artery perforator (v‐PAP) flap is limited in terms of the tissue volume that can be harvested but is a suitable graft for Japanese patients with relatively small breast sizes. The objectives of this study were to identify the parameter most closely correlated with v‐PAP flap weight on computed tomography angiography (CTA) images and to create an easy‐to‐use v‐PAP flap weight estimation formula by linear regression analysis using the identified parameter.

Patients and Methods

Thirty v‐PAP flaps in 25 patients who underwent breast reconstruction were retrospectively analyzed. Mean age was 46.1 (range: 32–73) years, and mean BMI was 20.0 (range: 15.3–23.6) kg/m2. On a CT horizontal section of the thigh taken at level of the center of the long axis of the flap, the following parameters were measured from the anterior margin of the gracilis muscle to the posterior margin of the semimembranosus muscle using image processing software: fat area, fat thickness, thigh circumference, and skin paddle area. Linear regression analysis was then performed with the weight of the harvested v‐PAP flap as the objective variable and the above parameters as explanatory variables to predict skin flap weight.

Results

Correlations with v‐PAP flap weight of each parameter were as follows: r = 0.66 (p < .0001) for fat thickness, r = 0.32 (p = .081) for total thigh area, r = 0.36 (p = .054) for thigh circumference, r = 0.27 (p = .153) for skin paddle area, and r = 0.84 (p < .0001) for fat area. Thus, the fat area had the strongest correlation with v‐PAP flap weight. The v‐PAP flap weight estimation formula obtained by linear regression analysis including fat area was as follows: 7.3 × fat area + 114 (coefficient of determination: R2 = 0.70, p < .0001, RMSE = 24). The engraftment rate of the 30 v‐PAP flaps was 100%. One patient developed postoperative venous thrombosis at the vascular anastomosis site, but underwent successful microsurgical revision, leading to flap salvage. During the >6‐month follow‐up period, there were no notable complications in the reconstructed breasts and donor sites.

Conclusions

The v‐PAP flap weight estimation formula we developed in this study showed a high correlation with measured values, allowing for easy estimation using only a single CTA horizontal section of the thigh.
Event‐triggered synchronization and H∞$$ {\mathcal{H}}_{\infty } $$ synchronization of coupled delayed reaction‐diffusion memristive neural networks
Authors: Lin Shanrong , Liu Xiwei , Huang Yanli
Published: January 2023

This paper settles event‐triggered synchronization and
synchronization matters for two types of coupled delayed reaction‐diffusion memristive neural networks (CDRDMNNs). First of all, several synchronization and
synchronization conditions are acquired for CDRDMNNs with state coupling in virtue of exploiting Lyapunov stability theory in combination with appropriate controllers of the triggering event. Then, event‐triggered synchronization and
synchronization for CDRDMNNs with spatial diffusion coupling are studied as well. Finally, the correctness of these deduced synchronization and
synchronization results is verified by two given numerical examples.
Urinary Metabolome Analysis Reveals Potential Microbiota Alteration and Electrophilic Burden Induced by High Red Meat Diet: Results from the French NutriNet‐Santé Cohort and an In Vivo Intervention Study in Rats
Authors: Mervant Loïc , Tremblay‐Franco Marie , Olier Maïwenn , Jamin Emilien , Martin Jean‐Francois , Trouilh Lidwine , Buisson Charline , Naud Nathalie , Maslo Claire , Héliès‐Toussaint Cécile , Fouché Edwin , Kesse‐Guyot Emmanuelle , Hercberg Serge , Galan Pilar , Deschasaux‐Tanguy Mélanie , Touvier Mathilde , Pierre Fabrice , Debrauwer Laurent , Guéraud Francoise
Published: January 2023

Scope

High red and processed meat consumption is associated with several adverse outcomes such as colorectal cancer and overall global mortality. However, the underlying mechanisms remain debated and need to be elucidated.

Methods and results

Urinary untargeted Liquid Chromatography‐Mass Spectrometry (LC‐MS) metabolomics data from 240 subjects from the French cohort NutriNet‐Santé are analyzed. Individuals are matched and divided into three groups according to their consumption of red and processed meat: high red and processed meat consumers, non‐red and processed meat consumers, and at random group. Results are supported by a preclinical experiment where rats are fed either a high red meat or a control diet. Microbiota derived metabolites, in particular indoxyl sulfate and cinnamoylglycine, are found impacted by the high red meat diet in both studies, suggesting a modification of microbiota by the high red/processed meat diet. Rat microbiota sequencing analysis strengthens this observation. Although not evidenced in the human study, rat mercapturic acid profile concomitantly reveals an increased lipid peroxidation induced by high red meat diet.

Conclusion

Novel microbiota metabolites are identified as red meat consumption potential biomarkers, suggesting a deleterious effect, which could partly explain the adverse effects associated with high red and processed meat consumption.
Environmental policies in a Stackelberg differential game
Authors: Cerqueti Roy , Correani Luca , Di Dio Fabio
Published: January 2023

We develop a Stackelberg differential game to analyze the economic effects of the reduction plan through two policy instruments, tradable permits and taxes on emissions. Emissions are a by‐product of firm output. The authority acts as a Stackelberg leader, able to set the optimal instrument's level in the light of a finite‐horizon environmental target. We show that the optimal solution of the game is dynamically consistent. Moreover, optimal environmental policies substantially impact the level and composition of economic activity. The differentiation between “clean” and “dirty” firms allows us to assess distributional effects and how environmental technology may influence the game's outcome. Results are shown to be robust under different parameterizations.
Safeguarding the retention of nurses: A systematic review on determinants of nurse's intentions to stay
Authors: Pressley Charlene , Garside Joanne
Published: January 2023

Aim

To explore factors that influence registered nurses' intention to stay working in the healthcare sector.

Design

A systematic review and narrative synthesis.

Methods

CINAHL, Medline and Cochrane library databases were searched from Jan 2010 to Jan 2022 inclusive and research selected using a structured criterion, quality appraisal and data extraction and synthesis were guided by Campbell's Synthesis Without Meta‐analysis.

Results

Thirty‐four studies identified that nurses stay if they have job satisfaction and/or if they are committed to their organizations. The factors permeating these constructs weigh differently through generations and while not an infallible explanation, demonstrate stark differences in workplace needs by age, which influence the intention to stay, job satisfaction, organizational commitment and ultimately nurse turnover.

Public Contribution

Environmental, relational and individual factors have bearing on improving nurse satisfaction and commitment. Understanding why nurses stay through a generational behavioural and career stage lens can bolster safeguarding nurse retention.
Micro models of COVID 19 pandemic governance: Reflections on the strategies taken by two states in India
Authors: Dash Roma Ranu , AR Anupama
Published: January 2023

Since the outbreak of the Covid 19 pandemic, governments across the world including India, a South‐Asian country is busy ‘strategizing’, ‘managing’ ‘containing’ the crisis to restrict its spread. But given the vastness and diversity of the Indian territory, one pan Indian model of is not possible and the states have been working in consonance with the centre in a matter of ‘cooperative federalism’ and are implementing various micro models of Covid 19 governance. This paper explores the micro models of governance strategies taken by states in India namely, Kerala located in its Southern coast and Odisha in the Eastern coast which have been experiencing disasters be it health or natural calamities. Inspite of the differences in social development indicators between both the states, they have managed to keep the death rates lower in the initial phases of the outbreak in comparison to other states. This is reflected in the strategies they took in controlling the pandemic like “preparedness” “decentralisation”, “community participation”. However, inspite of deploying various governance models, the gradual unlocking led to the explosion of positive cases as a result of which the challenges to deal with the pandemic still looms large.
Shell structure control of monodisperse polystyrene‐silver composite microspheres and synthesis of epoxy resin‐based anisotropic conductive adhesives
Authors: Liu Yang , Xu Lu , Liu Baijun , Zhang Mingyao
Published: January 2023

Monodisperse polystyrene‐silver (PS‐Ag) composite microspheres were used to enhance the electrical conductivity of epoxy resin‐based anisotropic conductive adhesives (ACAs). Specially designed PS‐Ag composite microspheres were used as conductive elements to construct anisotropic conductive arrays. In addition, the surface microstructure and morphology of PS‐Ag composite microspheres were controlled by adjusting the silver precursor concentration and implemented electroless plating method. The size and conductivity of the final composite microspheres used for ACAs were 2.572 μm and 81,967 S cm−1, respectively. In addition, diglycidyl ether of bisphenol‐A (DGEBA) epoxy resin and polyamide resin were used as the matrix resin and curing agent, respectively, to predict the optimum curing process parameters based on curing kinetics. Based on this premise, carboxyl‐terminated butadiene‐acrylonitrile (CTBN) and PS‐Ag composite microspheres were used as the toughening agent and conductive filler, respectively, and a facile strategy was developed to prepare ACAs (viz., PS‐Ag/Ep‐ACAs). As the PS‐Ag composite microspheres exhibited a submicron structure, PS‐Ag/Ep‐ACAs creatively exhibited satisfactory anisotropic electrical and mechanical properties. Therefore, the research strategy and fabrication methods proposed demonstrate immense potential for the fabrication of large‐scale ACAs in practical applications.
A micro‐macromechanical approach for analyzing creep in randomly oriented short fiber composites
Authors: Rafiee Roham , Ghamarzadeh Ali
Published: January 2023

The main purpose of this research is to develop a model investigating creep phenomenon in polymeric composites reinforced with randomly oriented short fibers. The creep phenomenon is first analyzed in a representative volume element of a long‐fiber composites at the scale of micro through an implicit approach. Then, creep analysis is performed at laminate level as the macro‐scale analysis. Then, creep response of a quasi‐isotropic laminate is obtained where the outputs of the micro‐scale analysis are fed as input data to the macro‐scale modeling. Laminate analogy is properly integrated with creep modeling technique to obtain the creep behavior of randomly oriented short fiber composites. The results of modeling are compared with published experimental data revealing the proper performance of the developed modeling for both short‐term and long‐term creep phenomena.
Preparation and characterization of hydrophilic and water‐swellable elastomeric nanocomposites
Authors: Mensah Bismark , Oduro Emmanuel
Published: January 2023

Highly polar and hydrophilic polymers; ethylene‐vinyl acetate (EVA), epichlorohydrin rubber (GECO), and polyethylene oxide (PEO) reinforced with fillers (carbon black (CB) and/or Silica) were used to prepare water‐swellable rubber nanocomposites. The study showed that although the high content of the GECO delayed vulcanization of the corresponding compounds, the sample filled with desired ratio of GECO/PEO/EVA or GPE, cross‐linked with peroxide exhibited the highest swelling performance of ⁓150%. The samples exhibited good re‐usability performance in the re‐swollen test, after drying. At prolonged water swelling, the tensile strength dropped drastically for compounds with high content of the GPE, due to weak filler‐matrix interactions. On the other hand, the incorporated GPE also increased the rebound resilience (%) property which is a key requirement in green tire fabrication. For example; peroxide cured sample coded SR3 (GPE‐15 phr CB) obtained ⁓30% resilience in non‐swollen state and ⁓53.5% after 1440 min of water‐swelling, which represents a dramatic development of over ⁓78% in rebound resilience. Thus, a proper balance between the GPE content, curing agent and the reinforcements may guarantee high water‐swelling performance and mechanical properties integrity for multifunctional applications such as wound healing, structural works, water collection from oil spillages, and for the development of water‐based sensors.
A Rasch analysis of a rubric that measures the quality of school‐level variables that support a school's implementation of a social and emotional learning program over time
Authors: Ji Peter
Published: January 2023

A Rasch analysis was conducted to assess a rubric that measures the quality of school‐level variables that support the implementation of a social and emotional learning (SEL) program. SEL planning teams from 84 schools rated the quality of school‐level variables (e.g., principal support, available funds, and resources) that support the implementation of an SEL program in their schools. A Rasch analysis suggested that the rubric was a two‐dimensional solution, Planning and Activity. Ratings were collected for 3 years. Cluster analysis demonstrated that there were five groups of schools with different trends in their implementation process. The analysis demonstrated that the rubric can be improved by revising items and writing additional items to measure the full range of implementation quality.
Specific interchain interactions of poly(ethylene 2,5‐furandicarboxylate) with polyglycolide acid blends and its effect on miscibility
Authors: Han Weiqiang , Liao Xia
Published: January 2023

Poly (ethylene 2,5‐furan dicarboxylate) (PEF) with excellent physical properties is considered to be a perfect industrial alternative for PET. In this paper, a series of PEF/PGA blends with different mass ratios were prepared, and the miscibility and interchain‐associated interactions of those blends were studied by differential scanning calorimetry, scanning electron microscopy, nuclear Magnetic Resonance Spectroscopy, FTIR spectroscopy, and wide‐angle X‐ray diffraction. Experiment results suggested that there are two specific interchain‐associated interactions between PEF and PGA, which made those two components have good miscibility over the entire composition range and caused the Tgs of the blends slightly lower than the theoretical value calculated by FOX equation. After sufficiently isothermal crystallized at 160 °C, the primary and secondary contribution of these two interchain‐associated interactions between PEF and PGA in blends is reversed. In other words, the interchain‐associated interactions composed of CO of PGA component and CH2 of PEF component is the primary role, the interchain‐associated interactions composed of CO of PEF component and CH2 of PGA component is the secondary role before isothermal crystallization, after isothermal crystallization, which are reversed.
Stacking Interactions and Photovoltaic Performance of Cs2AgBiBr6 Perovskite
Authors: Igbari Femi , Xu Fa-Feng , Shao Jiang-Yang , Ud-Din Faraz , Siffalovic Peter , Zhong Yu-Wu
Published: January 2023

Elpasolite Cs2AgBiBr6 also known as double perovskite has been touted in recent years as a promising alternative to the lead‐based perovskite for light harvesting. Its structure and properties mainly stem from the replacement of Pb2+ cation with a pair of aliovalent silver (Ag+) and bismuth (Bi3+) cations. Although the elpasolite Cs2AgBiBr6 exhibits improved stability, its photophysical properties and device performance are inferior to those of the Pb‐based perovskites. To date, numerous efforts have been geared toward the development of efficient Cs2AgBiBr6 solar cells. However, the indirect, wide bandgap and high exciton binding energy of Cs2AgBiBr6 have limited such efforts. This has been attributed to its low (zero) electronic dimensionality (0D), formation of small polaronic states, and interfacial imperfections with charge transporting layers. In this review, the different aspects of the elpasolite Cs2AgBiBr6 in relation to compositional and interlayer interactions in solar cell are discussed, and its suitability for photovoltaic application is assessed, accompanied by potential measures to further advance its performance. An alternate application of Cs2AgBiBr6 in photocatalysis, which takes advantage of its less toxicity and better stability, is also discussed.
Multicolored structural coloration of carbon nanotube fibers
Authors: Li Run , Zhang Shiliang , Chen Hang , Huang Ya , Wang Baoshun , Wu Xueke , Jiang Qinyuan , Zhao Siming , Wang Fei , Zhao Yanlong , Zhang Rufan
Published: January 2023

Carbon nanotube fibers (CNTFs) are endowed with excellent mechanical, electrical, and thermal properties and are considered promising candidates in numerous cutting‐edge fields. However, the inherent black color of CNTFs hinders their practical application in fields with high aesthetic requirements such as wearable devices and smart textiles. Due to the smooth surface and chemical inertness, CNTFs are hard to be dyed by conventional chemical dyes or colorful inks. Herein, we realize a structural coloration of CNTFs by coating them with two metal oxide layers via atomic layer deposition. The three elements of color, that is, hue, saturation, and brightness, can be controlled by adjusting the types and thickness of each oxide layer. Colorful CNTFs with wide color gamut and high saturation are achieved through different combinations. A film interference model is also established to reveal the mechanism of the structural coloration, which is a comprehensive result of thin‐film interference and surface roughness briefly. The calculated reflectance well fits the measured results by introducing surface roughness parameters. Moreover, the colored CNTFs are not iridescent because of retinal signal delay, which will further expand their applications.
Birth‐weight centile at term and school performance at 12 years of age: linked cohort study
Authors: Burger R. J. , Gordijn S. J. , Mol B. W. , Ganzevoort W. , Ravelli A. C. J.
Published: January 2023

Objective

Birth weight, fetal growth and placental function influence cognitive development. The gradient of these associations is understudied, especially among those with a birth weight considered appropriate‐for‐gestational age. The aim of this study was to evaluate the associations between birth‐weight centile and intellectual development in term/near‐term infants across the entire birth‐weight spectrum, in order to provide a basis for better understanding of the long‐term implications of fetal growth restriction and reduced placental function.

Methods

This was a population‐based cohort study of 266 440 liveborn singletons from uncomplicated pregnancies, delivered between 36 and 42 weeks of gestation. Perinatal data were obtained from the Dutch Perinatal Registry over the period 2003–2008 and educational data for children aged approximately 12 years were obtained from Statistics Netherlands over the period 2016–2019. Regression analyses were conducted to assess the association of birth‐weight centile with school performance. The primary outcomes were mean school performance score, on a scale of 501–550, and proportion of children who reached higher secondary school level.

Results

Mean school performance score increased gradually with increasing birth‐weight centile, from 533.6 in the 1st–5th birth‐weight‐centile group to 536.8 in the 81st–85th birth‐weight‐centile group. Likewise, the proportion of children at higher secondary school level increased with birth‐weight centile, from 43% to 57%. Compared with the 81st–85th birth‐weight‐centile group, mean school performance score and proportion of children at higher secondary school level were significantly lower in all birth‐weight‐centile groups below the 80th centile, after adjusting for confounding factors.

Conclusions

Birth‐weight centile is associated positively with school performance at 12 years of age across the entire birth‐weight spectrum, well beyond the conventional and arbitrary cut‐offs for suspected fetal growth restriction. This underlines the importance of developing better tools to diagnose fetal growth restriction and reduced placental function, and to identify those at risk for associated short‐ and long‐term consequences. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
Retrospective investigation of decreasing body temperature trends during anaesthesia in dogs
Authors: Sage Adrianna M. , Bossert Julia L. , Brunstein Kristin A. , Farrow Abigail F. , Perregrino Ali N. , Clark‐Price Stuart C.
Published: January 2023

Background

Hypothermia during the perianaesthetic period may lead to an increased risk of morbidity in veterinary patients. However, the timeline of the decrease in body temperature during general anaesthesia has been minimally investigated.

Methods

Anaesthetic records of 1097 client‐owned dogs were examined. Change in body temperature (ΔBT = baseline temperature – time point temperature) was plotted over time for all dogs. The slope of ΔBT was calculated for each 15‐minute interval, and the magnitude of the largest ΔBT and the time point at which the largest ΔBT occurred were determined for each record.

Results

A rapid decline in ΔBT occurred from 0 to 15 minutes, a slower decline occurred from 15 to 60 minutes and a plateau occurred from 60 to 240 minutes. The largest ΔBT occurred at 75 (15–240) minutes from baseline, with a maximum ΔBT of –2.06°C (–0.06°C to –8.72°C).

Limitations

This is a retrospective study. As such, there were missing data points and potential confounding factors could not be controlled for.

Conclusions

Anaesthetised dogs exhibited a distinct pattern of decrease in body temperature, with the most rapid reduction occurring within the first 15 minutes. The effects of procedures and anaesthetic agents on the timeline and pattern of heat loss warrant further investigation.
Streambed migration frequency drives ecology and biogeochemistry across spatial scales
Authors: Risse‐Buhl Ute , Arnon Shai , Bar‐Zeev Edo , Oprei Anna , Packman Aaron I. , Peralta‐Maraver Ignacio , Robertson Anne , Teitelbaum Yoni , Mutz Michael
Published: January 2023

The bed of fluvial ecosystems plays a major role in global biogeochemical cycles. All fluvial sediments migrate and although responses of aquatic organisms to such movements have been recorded there is no theoretical framework on how the frequency of sediment movement affects streambed ecology and biogeochemistry. We here developed a theoretical framework describing how the moving‐resting frequencies of fine‐grained sediments constrain streambed communities across spatial scales. Specifically, we suggest that the most drastic impact on benthic and hyporheic communities will exist when ecological and biogeochemical processes are at the same temporal scale as the sediment moving‐resting frequency. Moreover, we propose that the simultaneous occurrence of streambed patches differing in morphodynamics should be considered as an important driver of metacommunity dynamics. We surmise that the frequency of patch transition will add new dimensions to the understanding of biogeochemical cycling and metacommunities from micro‐habitat to segment scales. This theoretical framework is important for fluvial ecosystems with frequent sediment movement, yet it could be applied to any other dynamic habitat.

This article is categorized under:

Water and Life > Nature of Freshwater Ecosystems
Distributed Data Streams
Authors: Castenow Jannik , Feldkord Björn , Hanselle Jonas , Knollmann Till , Malatyali Manuel , Meyer auf der Heide Friedhelm
Published: January 2023

We consider a scenario where a server is wirelessly connected to countless sensor nodes that continuously measure data. The task of the server is to monitor the sensors’ data. More precisely, at each time step the server calculates a function defined over the current measurements of the sensors. Since the sensors only have small computational power and tight battery constraints, the communication between the server and the sensors should be as small as possible, i.e., we aim at minimizing the total number of messages that is transferred.

There are various conceivable problems for the setting above. We demonstrate our approaches on the following three: In the Top-k-Value Monitoring Problem, the server aims at identifying the k largest values. The Top-k-Position Monitoring Problem shifts the task to identify the sensors observing these values. Finally, the Count Distinct Monitoring Problem obliges the server to determine the number of distinct values currently observed.

For all three problems, we not only present communication-efficient protocols for one time step, we also show how it can be exploited if the input at sensors is similar between consecutive time steps to reduce the total communication on the long term. Thereby, we utilize different techniques – involving sampling, dynamic data structures, filter-based approaches, and combinations of them – to demonstrate their potential and their limits in the broad setting described above.
Scalable Text Index Construction
Authors: Bingmann Timo , Dinklage Patrick , Fischer Johannes , Kurpicz Florian , Ohlebusch Enno , Sanders Peter
Published: January 2023

We survey recent advances in scalable text index construction with a focus on practical algorithms in distributed, shared, and external memory.
A Custom Hardware Architecture for the Link Assessment Problem
Authors: Chinazzo André , Schryver Christian De , Zweig Katharina , Wehn Norbert
Published: January 2023

Heterogeneous accelerator enhanced computing architectures are a common solution in embedded computing, mainly due to the constraints in energy and power efficiency. Such accelerator enhanced systems dispatch data- and computing-intensive tasks to specialized, optimized and thus efficient hardware units, leaving most control flow tasks for the more generic but less efficient central processing units (CPUs). Nowadays, also high-performance computing (HPC) systems are becoming more heterogeneous by incorporating accelerators into the computing nodes.

In this chapter, we introduce the concept of heterogeneous computing and present the design of a hardware accelerator for solving the Link Assessment (LA) problem, in introduced Chapter 3. The hardware accelerator integrates its main dedicated processing units with a customized cache design and light-weight data path. We provide detailed area, energy, and timing results for a 28 nm application specific integrated circuit (ASIC) process and DDR3 memory devices. Compared to an CPU-based cluster, our proposed solution uses 38x less memory and is 1030x more energy efficient for processing a users-movies dataset with half a million edges.