bluuebunny/crossref_metadata_2025 huggingface dataset:
Engineering phenylalanine ammonia lyase to limit feedback inhibition by cinnamate and enhance biotransformation
Authors: Pavale Siddhi , Dalei Sudipt Kumar , Sokhal Preeti , Biswas Biswambhar , Meena Kunal , Adlakha Nidhi
Published: October 2023

Phenylalanine ammonia‐lyase (PAL) is a crucial enzyme for various biotechnology applications, such as producing phenols, antioxidants, and nutraceuticals. However, feedback inhibition from its product, cinnamic acid, limits its forward reaction rate. Therefore, this study aims to address the feedback inhibition in PAL using enzyme engineering strategies. Random and site‐directed mutagenesis approaches were utilized to screen mutant enzymes with ameliorated tolerance against cinnamic acid. A thermotolerant and cinnamate‐tolerant mutant was rationally identified using a high throughput screening method and subsequent biochemical characterization. We evaluated cinnamate affinity among the seven rationally selected mutations, and the T102E mutation was identified as the most promising mutant. This mutant showed a six‐fold reduction in the affinity of PAL for cinnamic acid and a two‐fold increase in operational stability compared with native PAL. Furthermore, the enzyme was immobilized on carbon nanotubes to increase its robustness and reusability. The immobilized mutant PAL showed greater efficiency in the deamination of phenylalanine present in protein hydrolysate than its free form. The rationale behind the enhancement of cinnamate tolerance was validated using molecular dynamic simulations. Overall, the knowledge of the sequence‐function relationship of PAL was applied to drive enzyme engineering to develop highly tolerant PAL.
Site‐Selective Electrochemical Oxidation of Carbohydrates
Authors: Kapetanović Elisa , Beil Sebastian B.
Published: October 2023

The site‐selective transformation of unprotected sugars poses significant challenges to synthetic chemists but comes with a reward of step‐economic and energy efficient protocols. By replacing stoichiometric oxidants with electricity, greener processes are anticipated. To date, mostly C3‐ and C6‐selective transformations have been developed urging for further developments. Herein, we call for action to synthetic chemists to tackle the associated challenges of site‐selective transformations of unprotected sugars toward challenging C2 and C4 regioisomers fueled by mild electroorganic transformations.
Catalytic Synthesis of Silanols by Hydroxylation of Hydrosilanes: From Chemoselectivity to Enantioselectivity
Authors: Huang Wei‐Sheng , Xu Hao , Yang Hua , Xu Li‐Wen
Published: October 2023

As a crucial class of functional molecules in organosilicon chemistry, silanols are found valuable applications in the fields of modern science and will be a potentially powerful framework for biologically active compounds or functional materials. It has witnessed an increasing demand for non‐natural organosilanols, as well as the progress in the synthesis of these structural features. From the classic preparative methods to the catalytic selective oxidation of hydrosilanes, electrochemical hydrolysis of hydrosilanes, and then the construction of the most challenging silicon‐stereogenic silanols. This review summarized the progress in the catalyzed synthesis of silanols via hydroxylation of hydrosilanes in the last decade, with a particular emphasis on the latest elegant developments in the desymmetrization strategy for the enantioselective synthesis of silicon‐stereogenic silanols from dihydrosilanes.
Catalytic Gasification and Reforming of Residual Biomass in a Bench Scale System with Low Cost Catalysts
Authors: Garcia Lina , Cordoba Misael , Dosso Liza , Nardi Franco , Vera Carlos , Quiroga Mónica , Busto Mariana , Badano Juan
Published: October 2023

This paper demonstrates the effectiveness of using of different catalysts for reforming tars contained in the syngas of biomass gasifiers. The conversion of the tar content allows to obtain high quality syngas and to maximize the gas fraction. A bench scale equipment consisting of an autothermal fluidized bed gasifier and a downstream packed bed reformer was used. Pine sawdust was selected as the feedstock for gasification. TGA analysis showed that the temperature must be above 350 °C to ensure the ignition of the biomass and maintain the process in an autothermal steady‐state. Dolomite and pyrolysis char were used to test of the fluidized bed catalysts. In the reformer, dolomite, pyrolysis char, iron doped activated carbon and spent HDS catalyst were used. All catalysts decreased the CO2 concentration in the product gas and increased H2, CH4 and CO. When iron doped activated carbon is used, tar contents below 60 g/Nm3 in the product gas could be obtained, reaching less than 1 g/Nm3. The best value of LHV (lower heating value) was obtained with pyrolysis char as a catalyst (4.8 MJ/Nm3). The results demonstrate that catalytic biomass gasification with downstream tar reforming with low‐cost catalysts is a promising solution for energy applications.
Colorimetric Synchronization of Drosophila Larvae
Authors: Hailstock Taylor , Terry Douglas , Wardwell‐Ozgo Joanna , Robinson Beverly V. , Moberg Kenneth H. , Lerit Dorothy A.
Published: October 2023

The rapid succession of events during development poses an inherent challenge to achieve precise synchronization required for rigorous, quantitative phenotypic and genotypic analyses in multicellular model organisms. Drosophila melanogaster is an indispensable model for studying the development and function of higher order organisms due to extensive genome homology, tractability, and its relatively short lifespan. Presently, nine Nobel prizes serve as a testament to the utility of this elegant model system. Ongoing advancements in genetic and molecular tools allow for the underlying mechanisms of human disease to be investigated in Drosophila. However, the absence of a method to precisely age‐match tissues during larval development prevents further capitalization of this powerful model organism. Drosophila spends nearly half of its life cycle progressing through three morphologically distinct larval instar stages, during which the imaginal discs, precursors of mature adult external structures (e.g., eyes, legs, wings), grow and develop distinct cell fates. Other tissues, such as the central nervous system, undergo massive morphological changes during larval development. While these three larval stages and subsequent pupal stages have historically been identified based on the number of hours post egg‐laying under standard laboratory conditions, a reproducible, efficient, and inexpensive method is required to accurately age‐match larvae within the third instar. The third instar stage is of particular interest, as this developmental stage spans a 48‐hr window during which larval tissues switch from proliferative to differentiation programs. Moreover, some genetic manipulations can lead to developmental delays, further compounding the need for precise age‐matching between control and experimental samples. This article provides a protocol optimized for synchronous staging of Drosophila third instar larvae by colorimetric characterization and is useful for age‐matching a variety of tissues for numerous downstream applications. We also provide a brief discussion of the technical challenges associated with successful application of this protocol. © 2023 Wiley Periodicals LLC.

Basic Protocol: Synchronization of third instar Drosophila larvae
Dracorhodin targeting CMPK2 attenuates inflammation: A novel approach to sepsis therapy
Authors: Zhang Wendan , Jiang Honghong , Huang Pengli , Wu Gaosong , Wang Qun , Luan Xin , Zhang Hongwei , Yu Dianping , Wang Hongru , Lu Dong , Wang Haonan , An Huazhang , Liu Sanhong , Zhang Weidong
Published: October 2023

Background

Despite all modern advances in medicine, an effective drug for treating sepsis has yet to be found. The discovery of CMPK2 spurred hopes for the treatment of sepsis. However, CMPK2‐untapped target inhibitors are still an enormous obstacle that has hindered the CMPK2‐centric treatment of sepsis.

Methods

Here, we found that the CMPK2 gene is highly expressed in the whole blood of sepsis patients by RNA‐Seq. First, recombinant CMPK2 was purified by a eukaryotic expression purification system, and the activity of recombinant CMPK2 was detected by the ADP‐GLO assay. Second, we developed an affinity MS strategy combined with quantitative lysine reactivity profiling to discover CMPK2 ligands from the active ingredients of Chinese herbs. In addition, the dissociation constant Kd of the ligand and the target protein CMPK2 was further detected by microscale thermophoresis technology. Third, we used this strategy to identify a naturally sourced small molecule, dracorhodin (DP). Using mass spectrometry‐based quantitative lysine reactivity profiling combined with a series of mutant tests, the results show that K265 acts as a bright hotspot of DP inhibition of CMPK2. Fourth, immune‐histochemical staining, ELISAs, RT‐qPCR, flow cytometry and immunoblotting were used to illustrate the potential function and related mechanism of DP in regulating sepsis injury.

Results

Our results suggest that DP exerts powerful anti‐inflammatory effects by regulating the NLRP3 inflammasome via the lipopolysaccharide (LPS)‐induced CMPK2 pathway. Strikingly, DP significantly attenuated LPS‐induced sepsis in a mouse model, but its effect was weakened in mice with myeloid‐specific Cmpk2 ablation.

Conclusion

We provide a new framework that provides more valuable information for new therapeutic approaches to sepsis, including the establishment of screening strategies and the development of target drugs to provide a theoretical basis for ultimately improving clinical outcomes for sepsis patients. Collectively, these findings reveal that DP is a promising CMPK2 inhibitor for the treatment of sepsis.
AS602801 treatment suppresses breast cancer metastasis to the brain by interfering with gap‐junction communication by regulating Cx43 expression
Authors: Yang Zhigang , Yang Liguo , Zhang Jun , Qian Chenzeyue , Zhao Yi
Published: October 2023

AS602801 has been reported as a potential drug candidate against brain metastasis by suppressing the gap‐junction communication between lung cancer stem cells and astrocytes. In this study, we aimed to study the molecular mechanism underlying the role of AS602801 in the treatment of brain metastasis in breast cancer. We utilized female athymic BALB/c nude mice and MDA‐MB‐231/BT‐474BR cells to establish experimental models. Polymerase chain reaction assays were performed to observe changes in the connexin 43 (Cx43) messenger RNA (mRNA) and c‐Jun N‐terminal kinase (JNK) mRNA levels. Dye transfer assay was used to observe the effect of AS602801 on cell–cell communication. An organotypic blood–brain barrier (BBB) model was utilized to observe the effect of AS602801 on transmigration through the BBB barrier. MTT (3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5 diphenyl tetrazolium bromide) assay and flow cytometry were performed to evaluate the proliferation and apoptosis of breast cancer cells co‐cultivated with astrocytes. AS602801 inhibited the upregulation of Cx43 and JNK in brain metastasized breast cancer cells in a dose‐dependent manner. Also, AS602801 significantly decreased the dye transfer rate from astrocytes to breast cancer cells, indicating the inhibitory effect of AS602801 on cell–cell communication. The transmigration ability of breast cancer cells co‐cultured with astrocytes was decreased by AS602801. Furthermore, AS602801 reduced the elevated Cx43/JNK mRNA expression in the co‐astrocyte group while suppressing the increased proliferation and promoting the decreased apoptosis of breast cancer cells co‐cultivated with astrocytes. AS602801 also suppressed the brain metastasis of breast cancer cells and increased mouse survival. AS602801 downregulates the expressions of JNK and Cx43 to suppress the gap‐junction activity. AS602801 also inhibits the communication between breast cancer cells and astrocytes, thus contributing to the treatment of brain metastasis in breast cancer.
Trisiloxane Surfactants Negatively Affect Reproductive Behaviors and Enhance Viral Replication in Honey Bees
Authors: Fine Julia D. , Cox-Foster Diana L. , Moor Kyle J. , Chen Ruiwen , Avalos Arian
Published: October 2023

Trisiloxane surfactants are often applied in formulated adjuvant products to blooming crops, including almonds, exposing the managed honey bees (Apis mellifera) used for pollination of these crops and persisting in colony matrices, such as bee bread. Despite this, little is known regarding the effects of trisiloxane surfactants on important aspects of colony health, such as reproduction. In the present study, we use laboratory assays to examine how exposure to field-relevant concentrations of three trisiloxane surfactants found in commonly used adjuvant formulations affect queen oviposition rates, worker interactions with the queen, and worker susceptibility to endogenous viral pathogens. Trisiloxane surfactants were administered at 5 mg/kg in pollen supplement diet for 14 days. No effects on worker behavior or physiology could be detected, but our results demonstrate that hydroxy-capped trisiloxane surfactants can negatively affect queen oviposition and methyl-capped trisiloxane surfactants cause increased replication of Deformed Wing Virus in workers, suggesting that trisiloxane surfactant use while honey bees are foraging may negatively impact colony longevity and growth. Environ Toxicol Chem 2024;43:222–233. © 2023 SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.
Toxicant Responses and Culturing Characteristics of Long-Term Laboratory-Reared and Field Populations of Ceriodaphnia dubia
Authors: Lydy Victoria R. , Regn Orithea Z. , Bouldin Jennifer L.
Published: October 2023

Ceriodaphnia dubia is a standardized test organism for regulatory toxicity testing of surface waters and commercial chemicals because of its simplicity to culture and responsiveness to toxicants. For testing convenience, C. dubia is often cultured for extended periods in the laboratory with little knowledge of the impact on subsequent generations. Extended laboratory rearing could impact how they respond to stressors and decrease the accuracy of test results. The present study investigated if C. dubia cultured for an extended period were representative of three recently collected field populations by comparing their culturing characteristics and sensitivities to toxicants. For culturing characteristics, the field cultures were more challenging because they had shorter body lengths, fewer neonates, and higher mortality rates than the laboratory culture. Comparative chronic toxicity tests with sodium chloride and the neonicotinoid insecticide thiamethoxam indicated that the laboratory and field organisms did not differ much in their toxicological responses but did differ in the variability of responses (percentage of coefficient of variation). The differences between the laboratory and field cultures found in the present study highlight the challenges of addressing discrepancies between laboratory and field applications in existing standardized methodologies. Environ Toxicol Chem 2024;43:159–169. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
Determinants of climate information service access and use among smallholder farmers in Bereh woreda, Ethiopia
Authors: Fikadu Tsion , Damene Shimeles , Teklu Abyiot
Published: October 2023

Climate information service (CIS) is a key component of a climate adaptation strategy that is expected to lessen climate risk. Access to and use of CIS among the local community are limited and constrained by various factors and are not supported by empirical research evidence. Therefore, this article analyzed CIS access and use determinants among smallholder farmers in Bereh woreda. The study applied a cross-sectional design with a mixed methodological approach. Data were collected through a survey of 219 smallholder farmer households, three focused-group discussions, and six key informant interviews. The collected survey data were analyzed using the heckprobit model to determine factors influencing smallholder farmers' access to and use of CIS. The heckprobit model results revealed that the determinants of CIS access and use had a statistical significance of log-likelihood of 1% (Wald χ2 = 45.2, p = 0.001), indicating a strong explanatory power. The selection model revealed that age and off-farm income significantly reduced the likelihood of accessing CIS, whereas mobile-phone ownership and male-headed households increased the likelihood of accessing it. Age, female-headed households, and farm size decreased the likelihood of using CIS, whereas mixed farming, radio ownership, and access to herbicide enhanced the likelihood of using it. This study, therefore, recommends intensive awareness creation and improving the delivery of diverse and reliable CIS to enhance agricultural productivity and smallholder farmers' resilience to the impacts of climate change. Integr Environ Assess Manag 2024;20:794–804. © 2023 SETAC
Plasma cell‐free DNA methylation analysis for ovarian cancer detection: Analysis of samples from a case‐control study and an ovarian cancer screening trial
Authors: Herzog Chiara , Jones Allison , Evans Iona , Reisel Daniel , Olaitan Adeola , Doufekas Konstantinos , MacDonald Nicola , Rådestad Angelique Flöter , Gemzell‐Danielsson Kristina , Zikan Michal , Cibula David , Dostálek Lukáš , Paprotka Tobias , Leimbach Andreas , Schmitt Markus , Ryan Andy , Gentry‐Maharaj Aleksandra , Apostolidou Sophia , Rosenthal Adam N , Menon Usha , Widschwendter Martin
Published: October 2023

Analysis of cell‐free DNA methylation (cfDNAme), alone or combined with CA125, could help to detect ovarian cancers earlier and may reduce mortality. We assessed cfDNAme in regions of ZNF154, C2CD4D and WNT6 via targeted bisulfite sequencing in diagnostic and early detection (preceding diagnosis) settings. Diagnostic samples were obtained via prospective blood collection in cell‐free DNA tubes in a convenience series of patients with a pelvic mass. Early detection samples were matched case‐control samples derived from the UK Familial Ovarian Cancer Screening Study (UKFOCSS). In the diagnostic set (ncases = 27, ncontrols = 41), the specificity of cfDNAme was 97.6% (95% CI: 87.1%‐99.9%). High‐risk cancers were detected with a sensitivity of 80% (56.3%‐94.3%). Combination of cfDNAme and CA125 resulted in a sensitivity of 94.4% (72.7%‐99.9%) for high‐risk cancers. Despite technical issues in the early detection set (ncases = 29, ncontrols = 29), the specificity of cfDNAme was 100% (88.1%‐100.0%). We detected 27.3% (6.0%‐61.0%) of high‐risk cases with relatively lower genomic DNA (gDNA) contamination. The sensitivity rose to 33.3% (7.5%‐70.1%) in samples taken <1 year before diagnosis. We detected ovarian cancer in several patients up to 1 year before diagnosis despite technical limitations associated with archival samples (UKFOCSS). Combined cfDNAme and CA125 assessment may improve ovarian cancer screening in high‐risk populations, but future large‐scale prospective studies will be required to validate current findings.
Deep dynamic face capture and recognition based on internet of things
Authors: Ai Cunchi , Lin Tianqi , Shi Wandi
Published: October 2023

Face recognition is widely used as identity authentication method in the Internet of Things (IoTs). However, compared with static camera, the background of IoT devices may change. Additionally, the facial expression or posture may change as well. Although face recognition has been researched for several decades, it is still a challenging task to design a robust face recognition system in IoT environment. This paper designs a special face recognition system by introducing deep transfer learning to adapt difference scenes in IoT environment. The face recognition system consists of two parts: terminal smart devices and cloud center. The terminal smart device consists of a camera to capture face picture, a wireless network part to communicate with cloud center, and a screen to show recognition result. The cloud center receives the face picture from terminal smart device and returns the face recognition result by using an offline deep transfer learning model. Compared with previous models, deep transfer learning model can better adapt different scenes. The experiments shows that the proposed face recognition system achieves more promising results than two source‐only models and two shallow transfer learning models.
Evaluating osteogenic effects associated with the incorporation of ascorbic acid in mineralized collagen scaffolds
Authors: Dewey Marley J. , Timmer Kyle B. , Blystone Ashley , Lu Crislyn , Harley Brendan A. C.
Published: October 2023

Current treatments for craniomaxillofacial (CMF) defects motivate the design of instructive biomaterials that can promote osteogenic healing of complex bone defects. We report methods to promote in vitro osteogenesis of human mesenchymal stem cells (hMSCs) within a model mineralized collagen scaffold via the incorporation of ascorbic acid (vitamin C), a key factor in collagen biosynthesis and bone mineralization. An addition of 5 w/v% ascorbic acid into the base mineralized collagen scaffold significantly changes key morphology characteristics including porosity, macrostructure, and microstructure. This modification promotes hMSC metabolic activity, ALP activity, and hMSC‐mediated deposition of calcium and phosphorous. Additionally, the incorporation of ascorbic acid influences osteogenic gene expression (BMP‐2, RUNX2, COL1A2) and delays the expression of genes associated with osteoclast activity and bone resorption (OPN, CTSK), though it reduces the secretion of OPG. Together, these findings highlight ascorbic acid as a relevant component for mineralized collagen scaffold design to promote osteogenic differentiation and new bone formation for improved CMF outcomes.
Palovarotene Action Against Heterotopic Ossification Includes a Reduction of Local Participating Activin A‐Expressing Cell Populations
Authors: Mundy Christina , Yao Lutian , Shaughnessy Kelly A. , Saunders Cheri , Shore Eileen M. , Koyama Eiki , Pacifici Maurizio
Published: October 2023

Heterotopic ossification (HO) consists of extraskeletal bone formation. One form of HO is acquired and instigated by traumas or surgery, and another form is genetic and characterizes fibrodysplasia ossificans progressiva (FOP). Recently, we and others showed that activin A promotes both acquired and genetic HO, and in previous studies we found that the retinoid agonist palovarotene inhibits both HO forms in mice. Here, we asked whether palovarotene's action against HO may include an interference with endogenous activin A expression and/or function. Using a standard mouse model of acquired HO, we found that activin A and its encoding RNA (Inhba) were prominent in chondrogenic cells within developing HO masses in untreated mice. Single‐cell RNAseq (scRNAseq) assays verified that Inhba expression characterized chondroprogenitors and chondrocytes in untreated HO, in addition to its expected expression in inflammatory cells and macrophages. Palovarotene administration (4 mg/kg/d/gavage) caused a sharp inhibition of both HO and amounts of activin A and Inhba transcripts. Bioinformatic analyses of scRNAseq data sets indicated that the drug had reduced interactions and cross‐talk among local cell populations. To determine if palovarotene inhibited Inhba expression directly, we assayed primary chondrocyte cultures. Drug treatment inhibited their cartilaginous phenotype but not Inhba expression. Our data reveal that palovarotene markedly reduces the number of local Inhba‐expressing HO‐forming cell populations. The data broaden the spectrum of HO culprits against which palovarotene acts, accounting for its therapeutic effectiveness. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
Classification of Fracture Risk in Fallers Using Dual‐Energy X‐Ray Absorptiometry (DXA) Images and Deep Learning‐Based Feature Extraction
Authors: Senanayake Damith , Seneviratne Sachith , Imani Mahdi , Harijanto Christel , Sales Myrla , Lee Peter , Duque Gustavo , Ackland David C.
Published: October 2023

Dual‐energy X‐ray absorptiometry (DXA) scans are one of the most frequently used imaging techniques for calculating bone mineral density, yet calculating fracture risk using DXA image features is rarely performed. The objective of this study was to combine deep neural networks, together with DXA images and patient clinical information, to evaluate fracture risk in a cohort of adults with at least one known fall and age‐matched healthy controls. DXA images of the entire body as, well as isolated images of the hip, forearm, and spine (1488 total), were obtained from 478 fallers and 48 non‐faller controls. A modeling pipeline was developed for fracture risk prediction using the DXA images and clinical data. First, self‐supervised pretraining of feature extractors was performed using a small vision transformer (ViT‐S) and a convolutional neural network model (VGG‐16 and Resnet‐50). After pretraining, the feature extractors were then paired with a multilayer perceptron model, which was used for fracture risk classification. Classification was achieved with an average area under the receiver‐operating characteristic curve (AUROC) score of 74.3%. This study demonstrates ViT‐S as a promising neural network technique for fracture risk classification using DXA scans. The findings have future application as a fracture risk screening tool for older adults at risk of falls. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
Scanning electron microscopy of digestive tract parasites in jungle cat (Felis chaus)
Authors: Hashemnia Shadi , Khovand Hosein , Ghahvei Younes , Nourollahifard Saeidreza
Published: October 2023

Among the 10 native cats of Iran, the Felis chaus is considered as one of the largely unknown species. Despite the reports on jungle cats in southeast Iran, there is no comprehensive information about their parasitic diseases. Scanning electron microscope (SEM) provides a valuable tool for the study of these organisms. In October 2022, a 15‐year‐old male jungle cat (F. chaus) was examined for gastrointestinal parasites using SEM which revealed exact parasite structures such as the mouth, shape of the lips, teeth and their position, papillae, excretory pore, and amphids. SEM of the Taenia taeniaeformis found in the F. chaus intestinal epithelium revealed that this tapeworm consisted of four unarmed suckers and a large armed rostellum. The rostellum was observed bearing double rings of alternating and circular hook arrangements. There were 21 large hooks in the anterior ring and 21 slightly smaller hooks in the posterior one. This study is the first report of Joyeuxiella echinorhyncoides from a jungle cat (F. chaus) in southeastern Iran. The rostellum was cylindrical and armed with thorn shape hooks that covered the whole rostellum with similar density. It was armed with 20–30 long hooks arranged in 16 rows. Four big suckers were visible at the base of the rostellum, two on each side. The suckers were round, and unlike the rostellum, these structures were unarmed. The results of the present study observed under SEM, indicated that organs such as sucker and rostellum in cestodes and mouth and the shape of lips and teeth in nematodes played a significant role in the biology of these helminths. The SEM reveals the surface structures and their relationships which results in better distinguishing the species and showing their detailed differences. More SEM studies need to be conducted on other species of cestodes and nematodes, along with pathological tests, to obtain more comprehensive and precise information about how these parasites harm this jungle cat host. The results of present study indicate that morphological details are important which should be considered in the classification. Meanwhile, external structures described herein using SEM, further investigation using transmission electron microscope provide more data on the biology of the parasites.

Research Highlights

Light microscopy is the first step to identify the parasites.

High magnification 3D images of the SEM reveal the surface structures of parasites and their relationships precisely.

SEM study of the parasites results in distinguishing the species and showing their detailed differences.
Effect of cadmium on the regulatory mechanism of steroidogenic pathway of Leydig cells during spermatogenesis
Authors: Ji HengLi , Fan Wei , Kakar Mohibullah , Alajmi Reem Atalla , Bashir Muhammad Amjad , Shakir Yasmeen
Published: October 2023

Cadmium is a male reproductive toxicant that interacts with a variety of pathogenetic mechanisms. However, the effect of cadmium on the regulatory mechanism of the steroidogenic pathway of Leydig cells during spermatogenesis is still ambiguous. Light microscopy, Western blot, immunohistochemistry, immunofluorescence, and quantitative polymerase chain reaction were performed to study the regulatory mechanism of the steroidogenic pathway of Leydig cells during spermatogenesis. The results indicated that in the control group, Leydig cells showed dynamic immunoreactivity and immunosignaling action with a strong positive significant secretion of 3β‐hydroxysteroid hydrogenase (3β‐HSD) in the interstitial compartment of the testis. Leydig cells showed a high active regulator mechanism of the steroidogenic pathway with increased the proteins and genes expression level of steroidogenic acute regulatory protein (STAR), cytochrome P450 cholesterol (CYP11A1), cytochrome P450 cholesterol (CYP17A1), 3β‐hydroxysteroid hydrogenase (3β‐HSD) 17β‐hydroxysteroid hydrogenase (17β‐HSD), and androgen receptor (AR) that maintained the healthy and vigorous progressive motile spermatozoa. However, on treatment with cadmium, Leydig cells were irregularly dispersed in the interstitial compartment of the testis. Leydig cells showed reduced immunoreactivity and immunosignaling of 3β‐HSD protein. Meanwhile, cadmium impaired the regulatory mechanism of the steroidogenic process of the Leydig cells with reduced protein and gene expression levels of STAR, CYP11A1, CYP17A1, 3β‐HSD, 17β‐HSD, and AR in the testis. Additionally, treatment with cadmium impaired the serum LH, FSH, and testosterone levels in blood as compared to control. This study explores the hazardous effect of cadmium on the regulatory mechanism of the steroidogenic pathway of Leydig cells during spermatogenesis.
Anger for good? Unethical‐behavior‐targeted leader anger expression and its consequences on team outcomes
Authors: Zhang Shimin , Mo Shenjiang , Liu Wu
Published: October 2023

Although leader anger expression targeted at employees' unethical behavior is pervasive in the workplace, we still know little about its theoretical meaning and consequences. To address this theoretical blind spot, we drew on fairness heuristic theory to investigate whether, how, and when unethical‐behavior‐targeted (UB‐targeted) leader anger expression affects team outcomes. Our findings from two time‐lagged field studies suggest that a punishment‐based distributive justice climate mediates the positive effects of UB‐targeted leader anger expression on team organizational citizenship behavior (OCB) and team viability. Moreover, leader moral decoupling weakens these indirect relationships. Specifically, the indirect relationships are weaker when the leader separated judgments of performance from those of ethics. These findings highlight the importance of a fairness perspective in understanding the consequences of leader anger expression targeted at unethical behaviors.
Layered structures of robustness and resilience: Evidence from cybersecurity projects for critical infrastructures in Central Europe
Authors: Maurer Florian , Fritzsche Albrecht
Published: October 2023

The article studies cybersecurity projects from the perspective of social systems theory. Measures taken to increase cybersecurity are aimed at the robustness and resilience of specific systemic entities in society. We argue that this does not necessarily mean that systems in which these entities are embedded become more robust or resilient. The article investigates the objectives of 20 projects funded by different public organizations to increase cybersecurity of critical infrastructures. The findings show that robustness and resilience are addressed by these projects on different layers of systems in society, without a clear picture of how they are supposed to fit together in a wider effort to protect society against disruption. The detailed analysis of the different facets of robustness and resilience addressed in cybersecurity projects paves the way for a better understanding of this problem. The research shows how organizations may avoid the negative consequences of measures to secure specific systemic entities in society in the case of critical infrastructures, other application scenarios, and digital innovation in general.
Pyoderma gangrenosum with severe systemic features, after augmentation mammoplasty
Authors: Beeckman Marine , Peeters Caroline , Coyette Maude , Marot Liliane , Yildiz Halil , Lengele Benoit , Baeck Marie
Published: October 2023

We report a rare life‐threatening presentation of postsurgical pyoderma gangrenosum (PG) after augmentation mammoplasty in a 32‐year‐old woman. Six days after surgery, the patient presented with fever and erythema at surgical wounds. In view of a suspected postsurgical infection, the patient was first treated with antibiotics and removal of breast protheses. In spite of this treatment, in a few days the patient developed a state of shock with multiorgan failure. The antibiotic coverage was broadened several times and multiple extensive surgical debridement with resection of the mammary glands were performed but did not improve the clinical situation. Twelve days after admission, the diagnosis of PG with systemic features was suspected and clinical improvement was observed within 24 h of methylprednisolone administration. PG can mimic the cutaneous and systemic features of necrotizing wound infection of surgical site. Biopsy and culture are critical to differentiating necrotizing neutrophilic dermatosis from necrotizing infection. The diagnosis of this less common form of PG is challenging and this case highlights how the frequent misdiagnosis with infection may result in ineffective antibiotic treatment and how the unnecessary surgical debridement may prolong and exacerbate the condition.
On‐Surface Interchain Coupling and Skeletal Rearrangement of Indenofluorene Polymers
Authors: Chen Qiang , Di Giovannantonio Marco , Eimre Kristjan , Urgel José I. , Ruffieux Pascal , Pignedoli Carlo A. , Müllen Klaus , Fasel Roman , Narita Akimitsu
Published: October 2023

On‐surface synthesis serves as a powerful approach to construct π‐conjugated carbon nanostructures that are not accessible by conventional wet chemistry. Nevertheless, this method has been limited by the types and numbers of available on‐surface transformations. While the majority of successful cases exploit thermally triggered dehalogenative carbon–carbon coupling and cyclodehydrogenation, rearrangement of appropriate functional moieties has received limited research attention. Here, the unprecedented interchain coupling and thermally induced skeleton rearrangement are described of (dihydro)indeno[2,1‐b]fluorene (IF) polymers on an Au(111) surface under ultrahigh vacuum conditions, leading to different ladder polymers as well as fully fused graphene nanoribbon segments containing pentagonal and heptagonal rings. Au‐coordinated nanoribbons are also observed. All structures are unambiguously characterized by high‐resolution scanning probe microscopy. The current results provide an avenue to fabricating a wider variety of π‐conjugated polymers and carbon nanostructures comprising nonhexagonal rings as well as rarely explored organometallic nanoribbons.
Unveiling the Role of Key Parameters during Molecular Growth for Optimal Poly(glycerol sebacate) Synthesis
Authors: Martín‐Cabezuelo Rubén , Naderpour‐Peñalver Alicia , Sigen A , Wang Wenxin , Vilariño‐Feltrer Guillermo , Vallés‐Lluch Ana
Published: October 2023

Poly(glycerol sebacate) (PGS) belongs to the hyperbranched polyesters family (HBP), which possesses an extensive variety of applications due to its tunable chemical and mechanical properties, together with its biocompatibility and biodegradability. However, the understanding of PGS synthesis becomes a challenge due to the lack of consistency when determining its synthesis parameters. Understanding these parameters is fundamental to control PGS synthesis and obtain a scalable and reproducible final product for biomedical applications. To unveil their effect on diverging PGS properties, diols are used as glycerol analogs and the reaction is chemically and thermally monitored, suggesting a heterogeneous reactivity of the exposed hydroxyl groups. Also, confinement of the prepolymerization is proven to be fundamental In order to maintain the equimolar ratio of initial monomers during synthesis. Early stages of the polycondensation (first 4 h) tend to linear and less branched oligomers by consuming primary hydroxyls rather than secondary hydroxyls. However, physicochemical characterization determines that a high degree of conversion (40%) is reached during these early stages. Afterward, the oligomers tend to condense through the secondary hydroxyls into a more crosslinked elastomer. This study demonstrates how hydroxyl affinity, water presence, and glycerol loss are crucial for the scalability and reproducibility of its final product.
Exponential stability and exact controllability of a system of coupled wave equations by second‐order terms (via Laplacian) with only one non‐smooth local damping
Authors: Akil Mohammad , Hajjej Zayd
Published: October 2023

The purpose of this work is to investigate the exponential stability of a second‐order coupled wave equations by Laplacian with one locally internal viscous damping. The strong stability is established by combining a unique continuation result and a Carleman estimate. Besides, the exponential stability is proved under (PMGC) condition on the damping region without any restriction on wave propagation speed (i.e., whether the two wave equations propagate at the same speed or not). The proof of this result relies on the frequency domain method combined with the multiplier techniques.
De‐embedding calibration for an electromagnetic dual probe using GCPW
Authors: Li Hui , Shao Weiheng , Tian Xinxin , Xue Shan , Wu Duo‐Long , Hou Bo
Published: October 2023

An ultrawideband de‐embedding calibration method (DCM) for a dual probe is proposed in this paper. Different from the conventional calibration method (CCM), in which a microstrip calibrator and the dual probe form a three‐port calibration network, the proposed calibration system is a four‐port network. By using two different lengths of grounded coplanar waveguide (GCPW) calibrators, namely line‐kit and through‐kit, the de‐embedded ‐parameter model of the calibration network is obtained. Measured results show that the ripple of the DCM with GCPW reduced by 59% of the CCM with the microstrip calibrator, and the phase delay has been almost compensated. In addition, the proposed method reduces the attenuation by approximately 0.7 dB at 10 GHz and 1.15 dB at 20 GHz. The calibration results indicate that the working frequency of the DCM is up to 22 GHz.
Frequency selective window blinds for indoor WLAN shielding
Authors: Hussaini Mohammed Abdullah , Sulaiman Mohamad Ismail , Kiani Ghaffer Iqbal , Khan Jahanzeb
Published: October 2023

Securing internal wireless communication of a corporate network from external eavesdropping requires electromagnetic (EM) shielding of the whole building, which may also block useful communication bands, such as mobile phone, radio, security, and television networks. Frequency selective surfaces provide selective spatial filtering of EM signals. A dual concentric modified square loop of unit‐cell dimension , fabricated on a window blinds material with dielectric constant 1.63 is presented for shielding indoor wireless network. The design resonates at WiFi and Bluetooth frequencies of 2.4 and 5 GHz and offers a measured suppression of at least −45 dB at both the frequency bands. Simulation and experimental results have been presented which exhibit stable and polarization insensitive responses in both, transverse electric and transverse magnetic modes, as well as angular stability for oblique incident angles up to 60°. The proposed Frequency Selective Window Blinds provide on‐demand, passive EM shielding and are easy to develop, install, and use.
8‐way high‐power high‐efficiency power divider/combiner
Authors: Yi Zixuan , Li Chenchen , Yang Xuexia , Li Meiling
Published: October 2023

In this letter, a low insertion loss power divider/combiner with a power capacity exceeding 100 kW is presented. The discussion focuses on the simultaneous achievement of high efficiency and high‐power capacity, based on the compensation analysis of discontinuous coaxial lines. An 8‐way power divider/combiner, operating within the frequency range of 7.73–9.33 GHz, has been designed, fabricated, and subjected to experimental testing. The experimental results demonstrate that within a relative bandwidth of 18.8%, the highest efficiency surpasses 98.49% and the power capacity exceeds 100 kW. Furthermore, the return loss of the multiport is better than 22.5 dB, the single port exhibits a return loss better than 20.7 dB, and the minimum isolation among the multiport is better than 27.5 dB. By comparison with other recently reported power dividers/combiners, the proposed power divider/combiner possesses both high‐power capacity and high efficiency simultaneously.
Spatial‐temporal V‐Net for automatic segmentation and quantification of right ventricle on gated myocardial perfusion SPECT images
Authors: Zhao Chen , Shi Shi , He Zhuo , Malhotra Saurabh , Wang Cheng , Zhao Zhongqiang , Li Xinli , Wen Haixing , Tang Shaojie , Zhou Yanli , Zhou Weihua
Published: October 2023

Background

Functional assessment of right ventricle (RV) using gated myocardial perfusion single‐photon emission computed tomography (MPS) heavily relies on the precise extraction of right ventricular contours.

Purpose

In this paper, we present a new deep‐learning‐based model integrating both the spatial and temporal features in gated MPS images to perform the segmentation of the RV epicardium and endocardium.

Methods

By integrating the spatial features from each cardiac frame of the gated MPS and the temporal features from the sequential cardiac frames of the gated MPS, we developed a Spatial‐Temporal V‐Net (ST‐VNet) for automatic extraction of RV endocardial and epicardial contours. In the ST‐VNet, a V‐Net is employed to hierarchically extract spatial features, and convolutional long‐term short‐term memory (ConvLSTM) units are added to the skip‐connection pathway to extract the temporal features. The input of the ST‐VNet is ECG‐gated sequential frames of the MPS images and the output is the probability map of the epicardial or endocardial masks. A Dice similarity coefficient (DSC) loss which penalizes the discrepancy between the model prediction and the manual annotation was adopted to optimize the segmentation model.

Results

Our segmentation model was trained and validated on a retrospective dataset with 45 subjects, and the cardiac cycle of each subject was divided into eight gates. The proposed ST‐VNet achieved a DSC of 0.8914 and 0.8157 for the RV epicardium and endocardium segmentation, respectively. The mean absolute error, the mean squared error, and the Pearson correlation coefficient of the RV ejection fraction (RVEF) between the manual annotation and the model prediction were 0.0609, 0.0830, and 0.6985.

Conclusion

Our proposed ST‐VNet is an effective model for RV segmentation. It has great promise for clinical use in RV functional assessment.
Rheumatology nurses' perceptions of undertaking a postgraduate education programme: A phenomenological study
Authors: Ryan Sarah , Hassell Andrew , Paskins Zoe , Rule Katrina , Brooks Michael , Tajuria Gulshan
Published: October 2023

Background

The expansion of the role of the rheumatology nurse specialist led to the instigation, in 1999, of the first Masters programme in rheumatology nursing, with the aim of supporting clinical advancement with evidence‐based practice. This study explored the experience of rheumatology nurses undertaking postgraduate study at Masters level.

Objectives

(1) To explore the perceptions and experiences of clinical nurse specialists undertaking a Masters programme in Rheumatology Nursing, including perceptions of impact. (2) To identify future educational needs.

Methods

Ten rheumatology nurses who had completed a Masters degree in rheumatology nursing participated in a semi‐structured video link or telephone interview conducted between 17th March 2021–17th May 2021. Interpretive phenomenological analysis was undertaken by two researchers and two public contributors.

Results

Four themes were identified: (i) Increased confidence and the development of new clinical skills. (ii) The perceived impact on the organisation; (iii) Benefits of face‐to‐face learning; and (iv) Continuing evolution of the rheumatology nurse specialist role. Participants reported increased confidence in clinical skills and felt that their learning had benefited their employing organisation. However, lack of time and insufficient managerial support could impede the implementation of new skills. Learning examination techniques, engagement in learning and peer support were seen as advantages of face‐to‐face learning. Future educational needs focused on diagnostic and prescribing skills.

Conclusions

Participant learners perceived that completing a face‐to‐face Masters in rheumatology increased confidence in delivering new clinical skills and fostered peer networks, whilst also benefiting their employing organisations. There is a need for organisational support to apply learning to the clinical setting.
Sound‐based cough peak flow estimation in patients with neuromuscular disorders
Authors: Recasens Bernat Bertran , Balañá Corberó Ana , Llorens Juana María Martínez , Guillen‐Sola Anna , Moreno Montserrat Villatoro , Escobar Greta García , Umayahara Yasutaka , Soh Zu , Tsuji Toshio , Rubio Miguel Ángel
Published: October 2023

Introduction/Aims

Cough impairment is common in individuals with neuromuscular disorders and is associated with respiratory infections and shorter survival. Cough strength is assessed by measuring cough peak flow (CPF) using a flow meter, but this method requires a complex device setup and trained staff. The aim of the study is to evaluate the reliability of a smartphone app to estimate CPF based on cough sounds in a cohort of individuals with neuromuscular disorders.

Methods

Individuals with neuromuscular disorders underwent CPF measurement with a flow meter and a smartphone app. A CPF <270 L/min was considered abnormal.

Results

Of the 50 patients studied, 26 had amyotrophic lateral sclerosis (52%), 15 had hereditary myopathies (30%), and 9 had myasthenia gravis (18%). The intraclass correlation coefficient (ICC) between the CPF measured with a flow meter and CPF estimated with cough sounds was 0.774 (p < .001) even if the patients had orofacial weakness (ICC = 0.806, p < .001). The smartphone app had 94.4% sensitivity and 100% specificity to detect patients with CPF of less than 270 L/min.

Discussion

Our findings suggest that sounds measured with a smartphone app provide a reliable estimate of CPF in patients with neuromuscular disorders, even in the presence of with orofacial weakness. This may be a convenient way to monitor respiratory involvement in patients with neuromuscular disorders, but larger studies of more diverse patient cohorts are needed.