bluuebunny/crossref_metadata_2025 huggingface dataset:
Morphological and Immunocytochemical Characterization of Tumor Spheroids in Ascites from High-Grade Serous Carcinoma
Authors: Miceska Simona , Škof Erik , Gašljević Gorana , Kloboves-Prevodnik Veronika
Published: October 2023

Tumor spheroids in the ascites of high-grade serous carcinoma (HGSC) are poorly described. Our objective was to describe their morphological features, cellular composition, PD-1 and PD-L1 expression, and survival correlation of these parameters. The density and size of spheroids were assessed in Giemsa-stained smears; the cell composition of spheroids, including tumor cells, immune cells, capillaries, and myofibroblasts, as well as PD-1 and PD-L1 expression on tumor and immune cells was assessed in immunocytochemically stained cell block sections. Forty-seven patients with primary HGSC and malignant ascites were included. A cut-off value for a spheroid density of 10% was established, which significantly predicted overall survival. However, spheroid size did not correlate with survival outcomes. Spheroids were primarily composed of tumor cells, but the presence of lymphocytes and macrophages was also confirmed. Moreover, capillaries were present in the spheroids of three patients, but the presence of myofibroblasts was not confirmed. PD-1 was expressed on lymphocytes but not on tumor cells. PD-L1 expression was seen on both tumor and immune cells, assessed by 22C3 and SP263 antibody clones but not by the SP142 clone. Our results highlight the potential of routine cytopathological techniques to analyze spheroids in HGSC ascites as a valuable tool to investigate their potential as prognostic markers.
Atopic Dermatitis in Italian Pre-School Children: Literature Review of Epidemiological Data with a Focus on Disease Prevalence and Severity
Authors: Neri Iria , Galeone Carlotta , Pelucchi Claudio , Ronci Gianluca , Matruglio Paolo , Pedone Maria Paola , Galli Elena
Published: October 2023

Atopic dermatitis (AD) is one of the most common diseases worldwide. Severe AD has a major impact on the quality of life of patients. We performed a systematic literature review on the epidemiology of AD in Italian pre-school children (age 0–5 years) and we assessed the available data on the severity of AD. In August 2022, we performed a bibliographic search using PubMed/Medline and EMBASE. We identified 10 studies with Italian data on the prevalence and/or incidence of AD in pre-school children. The period (12 months) prevalence of AD varied widely across studies, ranging between 4.0% and 42.2%, with median estimates of 14.3% among all studies and 11.8% among studies from 2010 onwards. Applied to the Italian population, this leads to a prevalence of 309,000–375,000 pre-school AD cases. Only one study computed the incidence of AD, reporting rates of 9 cases per 100 person-years in children aged 0–1 year, and 2.5 cases per 100 person-years in children aged 1–4 years. Severity data from Italy were also reviewed, across three identified three studies. A point estimate found 8.4% of cases were considered severe in one study based on the Patient-Oriented Eczema Measure (POEM), with an overall range of 7.8–11% across different Italian studies and according to various severity score types.
Child Attachment Representations and Parenting Stress in Mothers and Fathers of School-Age Children with a Diagnosis of Autism Spectrum Disorder: A Pilot Cross-Sectional Study
Authors: Giannotti Michele , Venuti Paola , De Falco Simona
Published: October 2023

Mothers and fathers of autistic children (ASD) tend to report elevated levels of parenting stress. Thus, it is critically important to understand which factors contribute to an imbalance between the perceived demands of parenting and the available psychological resources. To date, little is known about the association between child attachment representations and parenting stress. In this study, we first examined group differences in parenting stress levels based on child diagnosis and parents’ gender. Second, we explored the predictive role of child diagnosis, autism severity, and child attachment representations on parenting stress. The study involved 23 school-age children with ASD (IQ > 70), 27 without ASD (7–13 years), and their mothers (n = 50) and fathers (n = 50). Data were collected from 2017 to 2020. Parents completed the Social Responsiveness Scale 2 and the Parenting Stress Index—Short Form, while the children’s attachment representations were assessed using the School-age Assessment of Attachment. Parents of children with ASD reported higher stress compared with controls. No differences were found between mothers and fathers. Implicit attachment representations have been found to be associated with parenting stress only in mothers, while the severity of social impairment showed a significant effect on parenting stress in both parents. These findings revealed the potential benefit of adaptive attachment representations not only for children themselves but also for mothers and the family system, suggesting the bidirectional nature of parent–child relationships in the context of ASD. The uniqueness of maternal and paternal parenting experiences should be considered when parenting stress is addressed.
Can ChatGPT Guide Parents on Tympanostomy Tube Insertion?
Authors: Moise Alexander , Centomo-Bozzo Adam , Orishchak Ostap , Alnoury Mohammed K , Daniel Sam J.
Published: October 2023

Background: The emergence of ChatGPT, a state-of-the-art language model developed by OpenAI, has introduced a novel avenue for patients to seek medically related information. This technology holds significant promise in terms of accessibility and convenience. However, the use of ChatGPT as a source of accurate information enhancing patient education and engagement requires careful consideration. The objective of this study was to assess the accuracy and reliability of ChatGPT in providing information on the indications and management of complications post-tympanostomy, the most common pediatric procedure in otolaryngology. Methods: We prompted ChatGPT-3.5 with questions and compared its generated responses with the recommendations provided by the latest American Academy of Otolaryngology–Head and Neck Surgery Foundation (AAO-HNSF) “Clinical Practice Guideline: Tympanostomy Tubes in Children (Update)”. Results: A total of 23 responses were generated by ChatGPT against the AAO-HNSF guidelines. Following a thorough review, it was determined that 22/23 (95.7%) responses exhibited a high level of reliability and accuracy, closely aligning with the gold standard. Conclusion: Our research study indicates that ChatGPT may be of assistance to parents in search of information regarding tympanostomy tube insertion and its clinical implications.
Emirati Adolescents’ and Young Adults’ Usage of Social Media for Health Information
Authors: Barqawi Hiba Jawdat , Samara Kamel A. , Al Chame Hanae Qousae , Al Shyyab Ibrahim Marouf , Almaazmi Mariam A.
Published: October 2023

During the COVID-19 pandemic and in the years after, adolescents’ and young adults’ (AYAs) usage of social media increased. Social media has been shown to influence both the physical and mental behaviour of AYAs. The Emirates’ AYAs are among the world’s heaviest consumers of social media. This study aims to explore the usage of social media networks by AYAs for sharing and looking up health information, as well as interacting with local health systems, with a special focus on doctors and social media. This cross-sectional, descriptive study was used to collect comprehensive data from Arabic- and English-speaking Emirati students in grades 7 through 12 and university students between the months of December 2022 and April 2023. A total of 876 out of 930 responses were included. Of the responses, 27.71% were university students, with another 46.46% in grades 11 and 12. Three-fourths had a hospital or clinic visit in the last 6 months and 79.11% had good health perception. Smartphones were the most commonly used devices, at 92.12%. A total of 74.7% reported being able to obtain useful health information, with 40% having had a health decision influenced by it. Posting information on social media was not common, with only 32% posting such content (most commonly mood-related). Health information on social media by health authorities was considered the most trustworthy, with celebrities being the least trustworthy. More than half of AYAs searched for a physician before a visit, and the majority would not mind having a rash picture being posted on a public website if consent (verbal or written) was taken. Social media can influence the various health decisions an AYA might take and which doctors they might choose to see. Physicians should consider their presence and the content they present on social media carefully.
A Narrative Review of the Association between Prematurity and Attention-Deficit/Hyperactivity Disorder and Accompanying Inequities across the Life-Course
Authors: Fraiman Yarden S. , Guyol Genevieve , Acevedo-Garcia Dolores , Beck Andrew F. , Burris Heather , Coker Tumaini R. , Tiemeier Henning
Published: October 2023

Preterm birth is associated with an increased risk of neurodevelopmental and neurobehavioral impairments including attention-deficit/hyperactivity disorder (ADHD), the most common neurobehavioral disorder of childhood. In this narrative review, we examine the known associations between prematurity and ADHD and highlight the impact of both prematurity and ADHD on multiple domains across the pediatric life-course. We develop a framework for understanding the health services journey of individuals with ADHD to access appropriate services and treatments for ADHD, the “ADHD Care Cascade”. We then discuss the many racial and ethnic inequities that affect the risk of preterm birth as well as the steps along the “ADHD Care Cascade”. By using a life-course approach, we highlight the ways in which inequities are layered over time to magnify the neurodevelopmental impact of preterm birth on the most vulnerable children across the life-course.
Machine Learning Algorithms for Predicting Stunting among Under-Five Children in Papua New Guinea
Authors: Shen Hao , Zhao Hang , Jiang Yi
Published: October 2023

Preventing stunting is particularly important for healthy development across the life course. In Papua New Guinea (PNG), the prevalence of stunting in children under five years old has consistently not improved. Therefore, the primary objective of this study was to employ multiple machine learning algorithms to identify the most effective model and key predictors for stunting prediction in children in PNG. The study used data from the 2016–2018 Papua New Guinea Demographic Health Survey, including from 3380 children with complete height-for-age data. The least absolute shrinkage and selection operator (LASSO) and random-forest-recursive feature elimination were used for feature selection. Logistic regression, a conditional decision tree, a support vector machine with a radial basis function kernel, and an extreme gradient boosting machine (XGBoost) were employed to construct the prediction model. The performance of the final model was evaluated using accuracy, precision, recall, F1 score, and area under the curve (AUC). The results of the study showed that LASSO-XGBoost has the best performance for predicting stunting in PNG (AUC: 0.765; 95% CI: 0.714–0.819) with accuracy, precision, recall, and F1 scores of 0.728, 0.715, 0.628, and 0.669, respectively. Combined with the SHAP value method, the optimal prediction model identified living in the Highlands Region, the age of the child, being in the richest family, and having a larger or smaller birth size as the top five important characteristics for predicting stunting. Based on the model, the findings support the necessity of preventing stunting early in life. Emphasizing the nutritional status of vulnerable maternal and child populations in PNG is recommended to promote maternal and child health and overall well-being.
Need for Representation of Pediatric Patients with Obesity in Clinical Trials
Authors: Samuels Sherbet , Vaidyanathan Jayabharathi , Fletcher Elimika Pfuma , Ramamoorthy Anuradha , Madabushi Rajanikanth , Burckart Gilbert J.
Published: October 2023

Clinical trials are an integral aspect of drug development. Tremendous progress has been made in ensuring drug products are effective and safe for use in the intended pediatric population, but there remains a paucity of information to guide drug dosages in pediatric patients with obesity. This is concerning because obesity may influence the disposition of drug products. When pediatric patients with obesity are not enrolled in clinical trials, dosing options for use in this subpopulation may be suboptimal. Reliance on physiological-based dosing strategies that are not informed by evaluation of the pharmacokinetics of the drug product could lead to under- or over-dosing with ensuing therapeutic failure or toxicity consequences. Thus, representation of pediatric patients with obesity in clinical trials is crucial to understand the benefit-risk profile of drug products in this subpopulation. It is important to acknowledge that this is a challenging endeavor, but not one that is insurmountable. Collective efforts from multiple stakeholders including drug developers and regulators to enhance diversity in clinical trials can help fill critical gaps in knowledge related to the influence of obesity on drug disposition.
Do You Want to Increase Physical Activity in Adolescents? A School-Based Physical Activity Program Could Be an Efficient Way
Authors: Polo-Recuero Beatriz , Ordóñez-Dios Alfonso , Rojo-Tirado Miguel Ángel , Lorenzo Alberto
Published: October 2023

The aim of this study was to assess the effects of a classroom-based physical activity program, using bike desks, on academic and physical performance in adolescents. The Program to Enhance and Develop Active Lessons (PEDAL) was designed for this purpose, expecting an increase in students’ physical activity without any decrease in academic performance. This intervention based on pedal or bike desks—stationary bikes that integrate with a desk workspace—was conducted with 55 high- school students who were randomly assigned to two groups: a PEDAL group (n = 28, 14.86 ± 0.65 years old, 46.4% girls) and a control group (n = 27, 15 ± 0.68 years old, 51.9% girls). Throughout the intervention, the PEDAL students pedaled 4 days a week for 10 weeks during their Spanish-language arts lessons. The comparisons between the PEDAL group and the control group, as well as the pre- and post-test results, were statistically analyzed to verify the students’ physical activity (i.e., IPAQ-SF, heart rate monitors, polar OH1+), cardiorespiratory capacity (20 m shuttle run test), and academic performance (d2 test of attention and language proficiency test). Regarding the physical aspect, only the PEDAL group showed significant growth in their physical activity levels as compared to the pre-test data (p = 0.001), and they achieved higher results compared with the control group (p = 0.022) and less sedentary time than control students (p = 0.012). Concerning cardiorespiratory fitness, there were no post-test differences between the two groups (p = 0.697), probably because the physical activity performed with the bike desks was light–moderate. As far as academic performance is concerned, no significant post-test effects were discovered in either group on the levels of language competence (p = 0.48), attention (TOT, p = 0.432), and concentration (CON, p = 0.216). In conclusion, adolescents who move while learning, using bike desks, increase their light and moderate physical activity without any detriment to academic performance.
Centering Patient and Clinician Voices in Developing Tools to Address Pain Related School Impairment: A Phase I Study of a Virtual Reality School Simulation for Children and Adolescents with Chronic Pain
Authors: Logan Deirdre E. , Khanna Karina , Randall Edin , O’Donnell Shealyn , Reks Talis , McLennan Logan
Published: October 2023

Building on growing evidence supporting virtual reality (VR) interventions for pain management, this study describes the process of developing vReal-School (vRS), a VR-based school simulation for children and adolescents with chronic pain and associated school impairment. Following guidelines for developing user-centered VR interventions, initial phases of intervention development focus on understanding and incorporating patient and clinician perspectives when designing this digital health tool. Phase I entailed focus groups with patients undergoing intensive interdisciplinary pain treatment (IIPT). A total of 19 participants across four focus groups shared their experiences related to dealing with pain at school and provided initial feedback on the concept of a VR-based school simulation. In phase II, we pilot-tested a vRS prototype and collected patient and clinician feedback via mixed method approaches. Phase I results highlight four themes related to pain in school, including physical/environmental challenges and solutions, academic challenges and solutions, peer interaction challenges and solutions, and teacher interaction challenges and solutions. These themes guided the development of our vRS prototype. Nine patients and eleven treating clinicians then engaged with the vRS prototype and provided feedback via semi-structured interviews and validated self-report measures. The results indicate high levels of patient engagement/immersion (mean total score of 17.0 on the Child Presence Measure). Qualitative feedback from both groups identified positive aspects of vRS, including finding the simulation realistic and easy to use and offering ways to address school functioning goals that are not otherwise feasible in the IIPT setting. Areas for improvement included integrating more physical movement as well as increasing the number of scenarios and the level of demands of the tasks available. Both patients and clinicians found vRS to be useful in the IIPT context and relevant to treatment goals. This user input will guide subsequent iterations of intervention development.
IgG Seroreactivites to Viral Capsid Protein VP1 of JC and BK Polyomaviruses in Children at Early Ages with Special Reference to Parental Cofactors
Authors: Laine Hanna K. , Waterboer Tim , Syrjänen Kari , Grenman Seija , Louvanto Karolina , Syrjänen Stina
Published: October 2023

BK (BKPyV) and JC (JCPyV) polyomaviruses are widespread in humans. Transmission at an early age and the role of parents in spreading these viruses through the family are incompletely understood. Our aim was to determine the seroprevalence of BKPyV and JCPyV in infants at the age of 1, 2, 6, 12, 24, and 36 months and to assess the frequency of BKPyV and JCPyV seroconversion. A variety of maternal and paternal covariates were also tested as potential predictors of these early childhood infections. We used multiplex serology to analyze antibodies to BKPyV and JCPyV from baseline to 3-year follow-up visits. We observed that there was nearly perfect correlation in BKPyV and JCPyV serum IgG antibody levels between the mother-infant pairs during the first year of the infant’s life. No correlation among BKPyV antibody titers were found in father–child pairs, whereas JCPyV antibody levels of the father and child had a significant correlation at the 2-year follow-up visit. BKPyV infection may be associated with a child’s predisposition to allergy. In conclusion, after the decay of maternal antibodies, children start to develop their own immunity toward BKPyV and JCPyV, and horizontal transmission of infection in the family can occur.
A Study on the Microscopic Properties of the Oil–Stone Interfacial Phase of a Reclaimed Asphalt Mixture Based on Molecular Dynamics Simulation
Authors: Cao Yaoxi , Wang Yanhua , Li He , Chen Wuxing
Published: October 2023

In recent years, there has been a growing body of research focused on aged asphalt and recycled asphalt. Nevertheless, despite diligent endeavors, the precise micro-interaction mechanism occurring at the interface of weathered asphalt, reclaimed asphalt, and aggregates still eludes our understanding. This study leveraged molecular dynamics simulation technology to scrutinize the inherent behavior of aged asphalt and recycled asphalt at the micro-scale, elucidating the intricate interaction mechanism occurring at the interface of recycled asphalt, aged asphalt, and aggregates. The diffusion and adhesion properties of three distinct asphalt–aggregate interfaces were meticulously compared and comprehensively analyzed using advanced molecular dynamics simulation techniques. The findings revealed a substantial decline in the performance of aged asphalt, while the diffusion and adhesion properties of recycled asphalt were observed to be largely restored, reaching a remarkable level of approximately 85% in comparison to aged asphalt. The high-temperature performance, low-temperature performance, and water stability characteristics of both aged the asphalt mixture and recycled asphalt mixture were thoroughly investigated through rigorous laboratory testing of the asphalt mixtures. Based on the experimental findings, it was observed that the overall performance of the aged asphalt mixture exhibited a reduction of approximately 40%. However, through the process of regeneration, the overall performance of the asphalt mixture could be restored to approximately 90% of its non-aged counterpart.
Optical, Electrical and Structural Properties of ITO/IZO and IZO/ITO Multilayer Transparent Conductive Oxide Films Deposited via Radiofrequency Magnetron Sputtering
Authors: Seyhan Ayşe , Kartal Emre
Published: October 2023

In this study, we investigated the potential of multilayer TCO structures, specifically those made up of Indium Tin Oxide (ITO) and Indium Zinc Oxide (IZO), for crystalline silicon heterojunction solar cells (SHJ). We used the radiofrequency (RF) magnetron sputtering method to deposit various thin-film structures under various deposition temperatures and evaluated their electrical, optical, and morphological properties. The objective was to obtain films with lower sheet resistances and higher transmittances than those of single-layer thin films. Our results show that the ITO/IZO/ITO/IZO/ITO multilayer film structure deposited at 200 °C achieves the best sheet resistance of 18.5 Ohm/sq and a high optical transmittance of over 90% at a 550 nm wavelength. This indicates that multilayer TCO structures have the potential to be more optically and electrically efficient, and that they can improve the performance of optoelectronic devices. Finally, a power conversion efficiency of 17.46% was obtained for a silicon heterojunction (SHJ) solar cell fabricated using an ITO/IZO/ITO/IZO/ITO multilayer film structure deposited at 200 °C as a front TCO. Our study provides valuable insights into the field of TCOs and offers a promising avenue for future research.
Friction Sensitivity Test Experiment and Desensitization Mechanism of Nitrocellulose-Coated DNTF Explosive Crystals
Authors: Yuan Junming , Qin Yue , Liu Yan , Sun Hu , Huang Runsheng , Wang Jing , Han Tao , Wu Ruiqiang
Published: October 2023

In response to the problem of the high friction sensitivity of 3,4-bis(3-nitrofurazan-4-yl) furoxan (DNTF) in solid propellants, the inherent component of solid propellants, nitrocellulose (NC), was used to coat DNTF explosives via the water suspension method. The coated samples were characterized by scanning electron microscopy (SEM) and friction sensitivity tests at a fixed 66° swing angle, and molecular dynamics calculations were performed to study the friction sensitivity and desensitization mechanism of NC-based DNTF coatings. The results show that NC, when used as a coating layer, can form a white gel on the surface of DNTF crystals, which can effectively reduce the friction sensitivity of DNTF. The coating effect becomes more obvious as the NC content increases. When the NC content is 5%, the friction sensitivity decreases by 72%, and a prediction formula for the exponential decay of DNTF friction sensitivity is obtained. MD calculation data show that NC can weaken the stiffness, enhance the elastic-plastic properties, increase the ductility and toughness of DNTF materials, and effectively improve the mechanical properties of DNTF. By combining experiments and simulation calculations, while considering the compatibility of new components and changes in propellant energy and other unpredictable new issues, NC can be referred to as a better coating layer for DNTF, as it has a certain feasibility for improving the friction sensitivity of DNTF.
Graph-Theoretical Analysis of Biological Networks: A Survey
Authors: Erciyes Kayhan
Published: October 2023

Biological networks such as protein interaction networks, gene regulation networks, and metabolic pathways are examples of complex networks that are large graphs with small-world and scale-free properties. An analysis of these networks has a profound effect on our understanding the origins of life, health, and the disease states of organisms, and it allows for the diagnosis of diseases to aid in the search for remedial processes. In this review, we describe the main analysis methods of biological networks using graph theory, by first defining the main parameters, such as clustering coefficient, modularity, and centrality. We then survey fundamental graph clustering methods and algorithms, followed by the network motif search algorithms, with the aim of finding repeating subgraphs in a biological network graph. A frequently appearing subgraph usually conveys a basic function that is carried out by that small network, and discovering such a function provides an insight into the overall function of the organism. Lastly, we review network alignment algorithms that find similarities between two or more graphs representing biological networks. A conserved subgraph between the biological networks of organisms may mean a common ancestor, and finding such a relationship may help researchers to derive ancestral relationships and to predict the future evolution of organisms to enable the design of new drugs. We provide a review of the research studies in all of these methods, and conclude using the current challenging areas of biological network analysis, and by using graph theory and parallel processing for high performance analysis.
Two-Dimensional Uniform and Non-Uniform Haar Wavelet Collocation Approach for a Class of Nonlinear PDEs
Authors: Kumar Narendra , Verma Amit K. , Agarwal Ravi P.
Published: October 2023

In this paper, we introduce a novel approach employing two-dimensional uniform and non-uniform Haar wavelet collocation methods to effectively solve the generalized Burgers–Huxley and Burgers–Fisher equations. The demonstrated method exhibits an impressive quartic convergence rate. Several test problems are presented to exemplify the accuracy and efficiency of this proposed approach. Our results exhibit exceptional accuracy even with a minimal number of spatial divisions. Additionally, we conduct a comparative analysis of our results with existing methods.
Designing Microfluidic PCR Chip Device Using CFD Software for the Detection of Malaria
Authors: Austria Meynard , Garcia Jon Patrick , Caparanga Alvin , Tayo Lemmuel , Doma Bonifacio
Published: October 2023

Polymerase chain reaction (PCR) technique is one of the molecular methods in amplifying DNA for the detection of malaria. However, the collection and transportation of samples and the processing and dissemination of results via conventional PCR, especially when used for routine clinical practice, can hamper the technique’s sensitivity and specificity. The rampancy of such disease in the Philippines is aggravated by the limited supply of medical machinery and the poor economic state of the country; thus, the need to innovate a device for the early detection of malaria is necessary. With that, this study focuses on designing a microfluidic device that will mimic the function of a conventional genus-specific PCR based on the 18S rRNA gene to detect malaria parasites (Plasmodium falciparum) at low-grade parasitemia. The design was intended to be portable, accessible, and economical, which none from past literature has dealt with specifically for malaria detection. This in silico design is a first in the country specially crafted for such reasons. The proposed device was developed and simulated using ANSYS software for Computational Fluid Dynamics (CFD) analyses. The simulation shows that adding loops to the design increases its relative deviation but minimally compared to having only a straight path design. This indicates that looping is acceptable in designing a microfluidic device to minimize chip length. It was also found that increasing the cross-sectional area of the fluid path decreases the efficiency of the design. Lastly, among the three materials utilized, the chip made of polypropylene is the most efficient, with a relative deviation of 0.94 compared to polycarbonate and polydimethylsiloxane, which have relative deviations of 2.78 and 1.92, respectively. Future researchers may mesh the 44-cycle microfluidic chip due to the limitations of the software used in this study, and other materials, such as biocomposites, may be assessed to broaden the application of the design.
Off-Eutectic Growth Model for Solidifying Alloy from an Undercooled State
Authors: Xu Junfeng , Galenko Peter K.
Published: October 2023

Classical eutectic growth models are based on the use of eutectic composition. These models neglect the effect of primary phase formation, and their direct use in the rapid solidification process of off-eutectic (hypoeutectic and hypereutectic) alloys is absent. Combining the effect of the primary phase in the eutectic transformation and an off-eutectic composition, the solidification growth model is derived in the present work. The effect of the model and material parameters on solidification kinetics is discussed in comparison with experimental data. Computational results on the off-eutectic growth model show that the model agrees well with experimental data on the solidification kinetics of Ni–B and Ti–Si alloys.
Effects of Conjugation Spacers in Diketopyrrolopyrrole-Based Copolymers for All-Polymer-Based Photodiodes
Authors: Kang Hyunbum , Kim Hyungjun , Choi Ajeong , Yun Youngjun , Lee Gae Hwang
Published: October 2023

The selection of the π-conjugation spacers in semi-conducting polymer backbone is one of the important factors for determining the optoelectrical and morphological properties in organic photodiodes. To study the effects of π-conjugation spacers in donor–acceptor (D-A)-type alternating copolymers on their device performances in all-polymer-based photodiodes (all-PPDs), a series of diketopyrrolopyrrole (DPP)-based copolymers as polymer donors (PDs) were designed and synthesized. In detail, three different π-conjugation spacers, thiophene (T for P1), thienothiophene (TT for P2), and bithiophene (BT for P3), were incorporated into the DPP-based copolymer structures. Interestingly, all-PPDs based on the series of P1–P3 as PDs and N2200 as a polymer acceptor (PA) exhibited totally distinct device performances in terms of external quantum efficiency (EQE), dark current density (JD), and ideal detectivity (D*). The P1-based device showed suppressed JD (6.1 × 10−11 A/cm2 at −1 V) compared to those of the P2- and P3-based devices due to the lower lying of the highest occupied molecular orbital (HOMO) level of P1. However, the P3-based all-PPD showed higher EQE (16% at 630 nm wavelength and −1 V) compared to those of the P1- and P2-based devices. And, it mainly originated from the better molecular packing and final blend film morphology, as confirmed by morphological analyses.
Corrosion and Wear-Resistant Composite Zirconium Nitride Layers Produced on the AZ91D Magnesium Alloy in Hybrid Process Using Hydrothermal Treatment
Authors: Tacikowski Michał , Karpiniak Piotr , Marciniak Szymon , Słoma Jacek , Smolik Jerzy , Jakieła Rafał
Published: October 2023

The aim of the study was to investigate the possibility of an effective improvement in performance properties, including corrosion and wear resistance of magnesium AZ91D alloy using a surface engineering solution based on zirconium nitride composite surface layers produced on AZ91D alloy in a hybrid process using hydrothermal final sealing. Research results show that the formation of a composite ZrN-Zr-Al-type zirconium nitride layer on zirconium and aluminum sublayers results in a significant increase in resistance to corrosion and wear. The decrease in chemical activity of the sealed zirconium nitride composite layer on AZ91D, expressed by the displacement of the corrosion potential in the potentiodynamic test, reaches an outstanding value of ΔEcorr = 865 mV. The results of the SIMS chemical composition analysis of the layers indicate that the sealing of the composite layer occurs at the level of the aluminum sublayer. The composite layer reduces wear in the Amsler roll on block test by more than an order of magnitude. The possibility of effective sealing of zirconium nitride layers on the AZ91D alloy demonstrated in this study, radically increases the corrosion resistance and combined with the simultaneous mechanical durability of the layers, is of key importance from the point of view of new perspectives for application in practice.
First Demonstration of Extrinsic C-Doped Semi-Insulating N-Polar GaN Using Propane Precursor Grown on Miscut Sapphire Substrate by MOCVD
Authors: Mukhopadhyay Swarnav , Sanyal Surjava , Wang Guangying , Gupta Chirag , Pasayat Shubhra S.
Published: October 2023

In this study, carbon-doped semi-insulating N-polar GaN on a sapphire substrate was prepared using a propane precursor. Controlling the deposition rate of N-polar GaN helped to improve the carbon incorporation efficiency, providing a semi-insulating behavior. The material quality and surface roughness of the N-polar GaN improved with modified deposition conditions. C-doping using 1.8 mmol/min of propane gave an abrupt doping profile near the GaN/sapphire interface, which was useful for obtaining semi-insulating N-polar GaN grown on sapphire. This study shows that further development of the deposition process will allow for improved material quality and produce a state-of-the-art N-polar semi-insulating GaN layer.
Seasonal and Spatial Variability in the Bacterial Diversity in Haizhou Bay in the Southern Yellow China Sea
Authors: Zhao Zhangqi , Zhan Haoyu , Yan Tian , Zhang Dechao
Published: October 2023

Harmful algae blooms (HABs) can have significant adverse effects on coastal ecosystems and aquaculture resiliency. We collected samples from March to August at eight different stations in Haizhou Bay (China), a region with a high frequency of HABs, and used Illumina Novaseq high-throughput sequencing and multivariate statistical analysis to characterize the bacterial communities and their relationships with different environmental factors. We identified 27 phyla, 49 classes, 158 orders, 294 families, and 522 genera. Gammaproteobacteria, Alphaproteobacteria, Bacteroidia, Acidimicrobiia, Bacilli, Actinobacteria, Cyanobacteria, Clostridia, and Acidobacteria were the most abundant classes, and Acidobacteria, Bacteroidetes, Firmicutes, Actinobacteria, Chloroflexi, Proteobacteria, and Cyanobacteria were the keystone phyla. Based on the Mantel test and redundancy analysis, temperature was the main environmental factor affecting the structure of the bacterial communities, followed by silicate, dissolved organic phosphorus (DOP), and dissolved oxygen (DO). Among the genera with high OTU abundance, Nautella was co-related positively with DO and negatively with salinity; Planktomarina was co-related positively with salinity and negatively with nitrate and nitrite. Certain families (Flavobacteriaceae, Rhodobacteraceae, and Clade_I (SAR11 clade)) and genera (Methylophaga, Alteromonas, Oleiphilus, Marinobacter, Bacillus, Nautella, and Vibrio) had associations with phytoplankton species that were responsible for HABs. This research provides new insights into the characteristics of the bacterial communities that occur in coastal areas that have HABs and provides detailed descriptions of the spatial and temporal changes in the structure of these communities.
Two New Species of Nipponbathynella Schminke, 1973 from South Korea, with a Brief Discussion on Korean Parabathynellid Genera (Crustacea, Bathynellacea)
Authors: Ji Su-Jung , Min Gi-Sik
Published: October 2023

Parabathynellidae is a family well known for its diversity and is endemic to the interstitial hyporheic zone of South Korea. Two new parabathynellid species, Nipponbathynella yeongchunensis sp. nov. and N. gapcheonensis sp. nov., were found through groundwater sampling on riverbanks in South Korea. Nipponbathynella yeongchunensis sp. nov. can be distinguished from its congeners by the base socket of the two dorsal setae on the antennule’s first segment. Nipponbathynella gapcheonensis sp. nov. can be distinguished by the protopod of thoracopod II–IV with hairs. We provide morphological descriptions and remarks about the two new species with molecular information based on 18S rRNA and partial COI gene sequences. In addition, phylogenetic analysis, including Nipponbathynella Schminke, 1973, which had not been previously molecularly evaluated, was inferred. The results of the 18S rRNA gene phylogeny suggest a close relationship between the genera Nipponbathynella and Arisubathynella, as well as Europe–North American genera. We have also included a brief discussion and an identification key for the five known parabathynellid genera found in South Korea.
The Silent Extinction of Species and Taxonomists—An Appeal to Science Policymakers and Legislators
Authors: Löbl Ivan , Klausnitzer Bernhard , Hartmann Matthias , Krell Frank-Thorsten
Published: October 2023

The science of taxonomy, albeit being fundamental for all organismic research, has been underfunded and undervalued for about two generations. We analyze how this could happen, particularly in times of a biodiversity crisis, when we have increased awareness amongst the population and decision makers that knowledge about species we share the planet with is indispensable for finding solutions. We identify five major issues: the habit of holding taxonomy in low esteem; the focus on inappropriate publication metrics in evaluating scientific output; the excessive focus on innovative technology in evaluating scientific relevance; shifting priorities in natural history museums away from their traditional strengths; and changing attitudes towards specimen collecting and increasing legislation regulating collecting and international exchange of specimens. To transform taxonomy into a thriving science again, we urgently suggest significantly increasing baseline funding for permanent positions in taxonomy, particularly in natural history museums; reviving taxonomic research and teaching in universities at the tenured professor level; strongly increasing soft money for integrative taxonomy projects; refraining using journal-based metrics for evaluating individual researchers and scientific output and instead focusing on quality; installing governmental support for open access publishing; focusing digitizing efforts to the most useful parts of collections, freeing resources for improving data quality by improving identifications; requiring natural history museums to focus on collection-based research; and ending the trend of prohibitive legislation towards scientific collecting and international exchange of taxonomic specimens, and instead building legal frameworks supportive of biodiversity research.
Plumage Variation and Sex Ratio in the Brown-Backed Parrotlet (Touit melanonotus; Psittacidae)
Authors: Carcassola Marina Vivianne , Bocalini Fernanda , Francisco Mercival Roberto , Silveira Luís Fábio
Published: October 2023

The Brown-backed Parrotlet, Touit melanonotus, is a rare endemic bird to the Brazilian Atlantic Forest, currently considered as “Vulnerable” in the Brazilian Red List of Threatened Species. We estimated the sex ratio of a wild flock of T. melanonotus using molecular markers, examined morphological variation in 34 museum specimens to test for sexual dimorphism, and conducted a literature review about sex ratio in Psittacidae for comparative purposes. We found a sex ratio of 0.8:1 (male/female; n = 29) in T. melanonotus, and a χ2 Goodness-of-fit test showed no significant difference from equality (p > 0.05). We describe three main categories in plumage: the first (and most common) comprises uniformly lime green birds, slightly darker on the head. The second is composed of individuals who are overall lighter, with the breast feathers washed with light greenish gray, and feathers of the head being dark lime green, presenting a sharp contrast with the breast feathers. The third and the rarest one is composed of birds with light greenish gray underparts with emerald green and darker upper parts. T. melanonotus has no apparent sexual dimorphism. We found no evidence of geographic variation. Sex ratio deviation may not be a parameter increasing the vulnerability of the species. Data like these represent a big leap in the knowledge of the species and has the potential to help and inform conservation efforts.
Advancing Forensic Chemical Analysis to Classify Wild and Captive Turtles
Authors: Hopkins John B. , Frederick Cheryl A. , Yorks Derek , Pollock Erik , Chatfield Matthew W. H.
Published: October 2023

The diets and environments that individuals experience can vary greatly within and among wildlife populations. These individual experiences can be compared using the chemical signatures of animal tissues, which can differentiate animals into groups, including those raised in the wild versus those held in captive facilities. In this study, we compared different combinations of four stable isotope ratios and 15 trace elements derived from the claw tips of captive wood turtles throughout the eastern U.S. and wild wood turtles (Glyptemys insculpta) from Maine to develop predictive models used to determine their origins. The purpose of this work is to develop an objective statistical tool that law enforcement can use to help prosecute poachers. We found that the chemical signatures of 14 (12 trace elements and 2 stable isotope ratios) of the 19 markers we explored were different between wild and captive wood turtles, thus reflecting the differences in their diets and environments. We found that our stable isotope ratio model had nearly perfect predictive accuracy in classifying wild wood turtles as wild and captive wood turtles as captive, whereas our trace element and combined model were 100% accurate, thus validating this statistical approach for determining the origins of confiscated wood turtles from Maine.
Trophic Ecology during the Ontogenetic Development of the Pelagic Thresher Shark Alopias pelagicus in Baja California Sur, Mexico
Authors: Sánchez-Latorre Clara , Galván-Magaña Felipe , Elorriaga-Verplancken Fernando R. , Tripp-Valdez Arturo , González-Armas Rogelio , Piñón-Gimate Alejandra , Delgado-Huertas Antonio
Published: October 2023

The trophic ecology of the Pelagic Thresher shark (Alopias pelagicus) was evaluated based on chemical ecology using stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) in the vertebrae and muscles. Individuals were caught between August 2013 and October 2019 on both the coasts of Baja California Sur, Mexico. In Bahía Tortugas, the mean vertebrae (n = 35) values were 12.72 ± 1.06‰ (δ15N) and −14.79 ± 0.61‰ (δ13C), while in muscles (n = 32) these values were 16.63 ± 0.76‰ (δ15N) and −17.18 ± 0.39‰ (δ13C). In Santa Rosalía, the mean vertebrae (n = 125) isotopic values were 14.4 ± 1.59‰ (δ15N) and −14.18 ± 0.51‰ (δ13C), while in muscles (n = 43), these values were 18.08 ± 0.96‰ (δ15N) and −16.43 ± 0.34‰ (δ13C). These results show higher δ15N values in Santa Rosalía as an effect of baseline isotopic differences between the two regions, whereas the δ13C values were lower in Bahía Tortugas, suggesting offshore ecological behavior (p < 0.05). In Santa Rosalía, there were significant differences by sex for δ15N in muscle, whereas the δ13C showed ontogenetic shifts, indicating that neonates feed in coastal areas more commonly than juveniles or adults (p < 0.05). Neither sex nor ontogenetic differences were observed in Bahía Tortugas (p > 0.05), suggesting a high overlap between their isotopic niches. Therefore, Alopias pelagicus uses the same ecological niche throughout its life, and there is consistency between sexes. The mean trophic position for both tissues and regions was 4.5, which corresponds to a tertiary predator, without any differences between stages or sex. Due to their higher energetic needs, juveniles and females showed the greatest isotopic niche amplitude; thus, their ecological niche is the widest.
Effects of Raster Angle on the Elasticity of 3D-Printed Polylactic Acid and Polyethylene Terephthalate Glycol
Authors: Albadrani Mohammed Aqeel
Published: October 2023

Because of its numerous advantages, 3D printing is widely employed for a variety of purposes. The mechanical characteristics of 3D-printed items are quite important. 3D-printed polylactic acid (PLA) is a common thermoplastic polymer due to its excellent characteristics and affordable cost. Because of its enhanced characteristics, polyethylene terephthalate glycol (PETG) has recently received a lot of attention. Despite PETG’s potential appeal in the 3D-printing field, little research has been conducted to explore its qualities, such as the impacts of raster angle on elasticity, which could lead to the development of more accurate guidelines for inspection and assessment. In this regard, this study examines the mechanical characteristics of polylactic acid (PLA) and polyethylene terephthalate glycol (PETG) 3D-printing specimens with different raster angles. Test specimens with raster angles of 15° and 30° were printed, and the stress–strain responses were recorded and compared with the simulated profiles generated using ANSYS software. The results showed that the raster angle significantly affected the mechanical properties of both types of materials. The simulated profile matched well with the experimental profile only in the case of PLA printed with a raster angle of 15°. These findings imply that extra effort should be made to ensure that the raster angle is tailored to yield the optimal mechanical properties of 3D-printed products.
Features of Self-Organization during the Process of Mindfulness-Based Stress Reduction: A Single Case Study
Authors: Schiepek Günter , Marinell Tatjana , Aichhorn Wolfgang , Schöller Helmut , Harrer Michael E.
Published: October 2023

Compared to the extensive evidence of the effectiveness of mindfulness-based interventions, there is only a limited understanding of their mechanisms of change. The three aims of this study are (1) to identify features of self-organization during the process (e.g., pattern transitions), (2) to obtain an impression of the effects of continuous self-assessments and feedback sessions on mindfulness-related stress reduction, and (3) to test the feasibility of high-frequency process monitoring and process feedback. Concerning aim (1), the specific hypothesis is that change will occur as a cascade of discontinuous pattern transitions emerging spontaneously in the sense of not being a reaction to external input. This single case study describes changing patterns of multiple time series that were produced by app-based daily self-assessments during and after an 8-week mindfulness-based stress reduction program. After this MBSR program, the participant (a female nurse) continued the self-assessment and the mindfulness practice for a further 10 months. The results confirm findings on the positive effects of mindfulness programs for healthcare professionals, especially on coping with work-related stress. The analysis of the time series data supports the hypothesis of self-organization as a possible mechanism of change manifesting as a cascade of phase transitions in the dynamics of a biopsychosocial system. At the end of the year, the participant reported a beneficial impact of daily monitoring and systematic feedback on the change process. The results underline the feasibility and usefulness of continuous high-frequency monitoring during and after mindfulness interventions.