bluuebunny/crossref_metadata_2025 huggingface dataset:
The finite difference method for the fourth‐order partial integro‐differential equations with the multi‐term weakly singular kernel
Authors: Wu Lijiao , Zhang Haixiang , Yang Xuehua
Published: August 2022

This paper is concerned with an efficient numerical method for a class of fourth‐order partial integro‐differential equations (PIDEs) with weakly singular kernel. Due to the presence of the weakly singular kernel, the exact solution has singularity near the initial time
. The proposed method is constructed on the graded meshes, which can achieve the second‐order convergence in time for weakly singular solutions. The product integral rule of the Riemann–Liouville fractional integral with the generalized time‐stepping is used for the time discretization, and the standard central difference formula is used for the space discretization. The stability and convergence of the method are proved, and the optimal error estimates in the discrete
‐norm and
‐norm are obtained. Numerical results show the effectiveness of the proposed method. Further, by the extrapolation method, we improve the convergence order in space and time to four order, respectively.
Consumption of Artificial Sweetener Acesulfame Potassium Increases Preterm Risk and Uterine Contraction with Calcium Influx Increased via Myosin Light Chain Kinase–Myosin Light Chain 20 Related Signaling Pathway
Authors: Chiang Yi‐Fen , Chen Hsin‐Yuan , Lai Yu‐Han , Ali Mohamed , Chen Yang‐Ching , Hsia Shih‐Min
Published: August 2022

Scope

The consumption of artificial sweeteners has been rapidly increasing, with potentially hazardous effects on human reproduction. This study aims to explore the effect of Acesulfame Potassium (Ace K) and its potential mechanism to induce uterine contraction through in vitro, ex vivo, in vivo, and clinical observation studies.

Methods and results

Used ex vivo and in vitro studies to analyze its effect on uterine contraction and involved signaling pathway. Used the long‐term, high‐dose exposure to examine Ace K's affection for contractive‐related protein expression. By involving a cohort of 613 participants, to assess the dose‐responsiveness of Ace K consumption and calculate the odd ratio of Ace K consumption and the relationship with preterm risk. Animal studies show increasing uterine contraction, cytokine secretion, and altered contraction‐related protein expression. Human data show that higher consumption of Ace K may be related to early delivery.

Conclusion

Long‐term high‐dose exposure to Ace K can induce uterine hypercontraction, increase cytokine secretion, and alters contraction‐related protein expression. These findings suggest that women who suffer from uterine hypercontraction causes painfulness should pay more attention to the zero‐ or low‐calorie soft drinks or food products containing Ace K.
Appetite and quality of life in amyotrophic lateral sclerosis: A scoping review
Authors: Sarmet Max , Kabani Aamna , Maragakis Nicholas J. , Mehta Ambereen K.
Published: August 2022

Loss of appetite is related to undesirable loss of weight in amyotrophic lateral sclerosis (ALS) and affects up to two thirds of people with this disease. Little is known about the instruments used to measure appetite loss, its impact on quality of life (QoL), or strategies used to improve loss of appetite. In this study we aim to characterize the existing literature on the symptom of appetite loss in ALS through a systematic scoping review following the framework by Arksey and O'Malley and PRISMA guidelines. Studies assessing appetite in people with ALS (pALS) published in English and indexed on Web of Science, PubMed, and Scopus databases were included. A total of 156 full references were identified, of which 10 articles met the inclusion criteria and were eligible for data synthesis after screening. Seven unique instruments were used to assess appetite across the included studies, most commonly the Council of Nutrition Appetite Questionnaire. No studies included a subjective assessment of appetite loss. A total of 12 unique potential associated factors across five studies were identified. QoL was measured in seven studies using nine different QoL measurement tools. Few studies measure appetite in pALS and there is no consensus on the assessment tool used. Few studies evaluated the impact of appetite as a symptom on QoL. Furthermore, the heterogeneity of outcomes and risk factors of the existing data limit the clinical application of these findings. Future studies are needed to guide clinical management and interventions for people with ALS and appetite loss.
Characterizing the Flow Regime in Brook Trout Incubation Habitats and Implications for Management in a Hydro-Regulated River
Authors: Slongo Stephen A. , McLaren Brian E. , Mackereth Robert W. , Siddiqui Sohail , Tyhuis Raymond , Gibson Daniel , Rennie Michael D.
Published: August 2022

The operation of dams, diversions, and power generation facilities unavoidably influence the ecological function of rivers. We evaluated vertical and horizontal hydraulic gradients and subsequent water temperature changes in the hyporheic zone of a spawning area for Brook Trout Salvelinus fontinalis in a managed Lake Superior tributary in Ontario, then conducted a laboratory-based experiment to show the impact of cold shock during incubation on the timing of larval emergence and survival. Upwelling groundwater was observed at the spawning area during the monitoring period (October 28, 2016, to January 11, 2017); hyporheic water temperatures remained above 3.7°C, whereas ambient river temperature above the substrate fell to 1.5°C until water was released from the upstream control dam. After the release event, water level increased by 0.9 m over the spawning area, and within 24 h, vertical and horizontal flow gradients were reversed in the hyporheic zone; downwelling conditions were observed for 30 h between surface and hyporheic water 1.8 m below substrate, and hyporheic water temperature decreased in unison. Hyporheic temperatures at shallow inshore sites fell below 1°C for more than 53 h. In the laboratory, applying a worst-case scenario of dam-induced cold shock on Brook Trout redds using historic monitoring records (i.e., <1.0°C for 40 h), we found no appreciable effect on survival and development timing of incubating Brook Trout eggs compared with a control group. Survival from fertilization to hatching was high for both treatment and control groups (>90%) and lower from fertilization to emergence (55%). Overall, our results suggest that standard winter operating procedures on a Lake Superior tributary had little impact on Brook Trout egg survival and development time to hatching and emergence; however, our findings also suggest that staged winter discharges would lessen the reversal of flow in the hyporheic zone and the magnitude of temperature changes experienced at Brook Trout redds.
Nutrition education with or without oral nutrition supplements has contrasting effects on nutrition status in older adults: A randomized controlled study
Authors: Xie Hua , Qiao Li Hua , Zhao Yue , Yan Zijie , Bai Huijin , Wang Yan , Ye Tingting , Yu Jun , Du Qin , Sun Jianqin
Published: August 2022

Background

Oral nutrition supplements (ONSs) play an important role in the management of malnutrition. This aim of study was to examine whether a comprehensive intervention, combining ONSs, family‐centered health education, and nutrition and medical consultations, could improve the nutrition and health status of malnourished older adults living in community dwellings.

Methods

A randomized controlled trial was conducted from October 2017 to May 2018 in Shanghai. All participants were screened using the Mini Nutritional Assessment‐Short Form (MNA‐SF). Participants with MNA‐SF scores ≤11 and age ≥65 were selected. Participants with potential nutrition risk were randomized into two groups: intervention group (n = 101) were prescribed ONSs (400 kcal/day) and family‐centered nutrition education (once every 2 weeks) and control group (n = 100) received only family‐centered nutrition education. Anthropometric measurements, including weight and height, and nutrition and functional scales, including MNA‐SF, grip strength, and activities of daily living scores, were collected at the beginning of the study and 12 weeks later.

Results

Of the 201 study participants, 182 completed the study (mean age, 75.48 ± 7.47 years). After 12 weeks, nutrient intake improvements in the intervention group (+370.6 ± 432.6 kcal/day, +17.6 ± 24.1 g/day) exceeded that of the control group (−67.5 ± 378.2 kcal/day, −0.9 ± 16.7 g/day). In addition, improvements in weight, body mass index, and handgrip strength were significantly higher in the intervention vs control group (P < .05).

Conclusion

Comprehensive nutrition interventions improved nutrition status in malnourished older people living in community dwellings. Use of ONSs may be a good strategy to improve nutrition status and strength in community‐dwelling older adults.
Microbiome profile informs cleansing and storage practices for reusable feeding tube stylets in critical care
Authors: Bourgault Annette M. , Deb Chirajyoti , Aguirre Lillian , Xie Rui , Rathbun Kimberly Paige , Sole Mary Lou
Published: August 2022

Background

Cleansing and storage practices for reusable feeding tube stylets are varied and lack consensus guidelines. Almost 40% of critical care nurses do not cleanse reusable stylets. Our proof‐of‐concept study aimed to identify potential microbial contamination of stylets before and after cleansing with 70% isopropyl alcohol to establish practice standards.

Methods

This prospective, exploratory pilot study sampled reusable feeding tube stylets using three different stylet sample sets. Set 1 included human participant stylets sampled for microbiome profile precleansing, and postcleansing and reinsertion into feeding tubes (n = 4). Sets 2 and 3 included stylets stored at the bedside. Set 2 included precleansed stylets for microbiome profiles (n = 5). Set 3 included precleansed and postcleansed stylets sampled for quantitative cultures (n = 5). Careful handling and storage protocols were used. Microbiome profiling used 16s ribosomal RNA gene amplicon sequencing.

Results

Bacterial species identified on stylets were primarily common microflora and opportunistic pathogens, including Streptococcus pneumoniae, Staphylococcus aureus, Pseudomonas fulva, Cutibacterium acnes, Prevotella melaninogenica, and Lactobacillus paracasei. Microbiological culturing of stylet samples (set 3) did not yield growth for 9/10 samples; Staphylococcus capitis was identified in one postcleansed sample. Mean bacterial species diversity (alpha diversity) decreased following alcohol cleansing (M = 2.54 pre, M = 1.5 post; P = 0.006).

Conclusion

The abundance of several potentially opportunistic pathogens indicated plausible risk for gut contamination secondary to reinsertion of stylets into small‐bore feeding tubes. Stylet cleansing with 70% isopropyl alcohol reduced bacterial burden on the stylets, although viability was unknown. Careful cleansing, handling, and storage protocols for reusable stylets are necessary to minimize contamination.
Container placement and migration strategies for cloud, fog, and edge data centers: A survey
Authors: Kaur Kiranpreet , Guillemin Fabrice , Sailhan Francoise
Published: August 2022

The last decade has witnessed important development of network softwarization that has revolutionized the practice of networks. Virtualized networks bring novel and specific requirements for the control and orchestration of containerized network functions that are scattered across the network. In this regard, the migration of virtualized network functions plays a pivotal role to best meet the requirements of optimal resource utilization, load balancing and fault tolerance. The purpose of this survey is to offer a detailed overview of the progress on container migration so as to provide a better understanding of the trade‐off between the benefits associated with the migration and the practical challenges. The paper includes a classification of the placement algorithms that map the containerized network functions on the virtualized infrastructure. Following, a taxonomy of the migration techniques that perform the transfer of the containerized microservices is proposed.
Experiences of using clinical pathways in hospitals: Perspectives of quality improvement personnel
Authors: Hwang Jee‐In , Tchoe Ha Jin , Chung Soojin , Park Eunji , Choi Miyoung
Published: August 2022

Aim

This study aimed to explore the experiences of quality improvement personnel in implementing clinical pathways (CPs) in Korean hospitals.

Design

A qualitative study using focus‐group interviews was conducted with healthcare professionals in charge of CP development and management in hospitals.

Methods

Sixteen quality improvement personnel from eight tertiary and seven general hospitals were recruited using purposive sampling. The verbatim transcribed data were analysed using qualitative content analysis.

Results

Three key themes emerged: (1) the primary focus of CP development on surgeries through concerted efforts between management and frontline healthcare professionals; (2) CP fidelity management using indicators and feedback to relevant staff or departments; and (3) positive outcomes, despite concerns about system safety. The factors affecting CP use included availability of clinical evidence, flexibility of CPs, top management and clinical leadership, physicians' perceptions of CPs, computerized support systems, and external policies and regulations.
Psychometric properties of the Korean adaptation of the communities advancing resilience toolkit (CART) assessment survey
Authors: Kim Eun‐Mi , Kim Gwang Suk , Kim Heejung , Pfefferbaum Betty
Published: August 2022

Aims

This study aimed to establish a cross‐cultural adaptation of the Communities Advancing Resilience Toolkit (CART) assessment survey for Korean communities (K‐CART) and evaluated its psychometric properties of K‐CART.

Design

A cross‐sectional study design was used.

Methods

A forward and backward translation of the CART was conducted. The psychometric properties of K‐CART were evaluated with test–retest reliability, internal consistency, content validity and construct validity. A field study was conducted involving 315 older adults in Pohang city, South Korea from January to March, 2019. Two versions of K‐CART were analysed, based on the four‐factor and the expanded five‐factor K‐CART.

Results

The test–retest reliability and internal consistency were acceptable (intraclass consistency coefficient = .90). The consistency reliability was satisfactory (Cronbach's α = 0.91). The content validity index (CVI) was found to be acceptable; wherein the item‐CVI and scale‐CVI were both 0.95. Confirmatory factor analysis confirmed that the construct validity of the expanded K‐CART with five factors reached a more acceptable model fit (χ2/df = 2.27, CFI = 0.89, TLI = 0.86, RMESA = 0.05).
Experiences of nurses working in nurse‐led clinics in Traditional Chinese Medicine hospitals: A focused ethnographic study
Authors: Dong Zhaoyang , Wei Lin , Sun Xinglan , Xiang Jiagen , Hu Yanan , Lin Meizhen , Tan Yibing
Published: August 2022

Background

Traditional Chinese Medicine (TCM) nurse‐led clinics (NLC) is an innovative working model in China, representing the specialization and extension of nurses’ role. However, as a pioneer in TCM nursing, this new model of working is facing both opportunities and challenges because it is known little about the operational status of NLCs.

Aims

To explore the experiences of nurses who work in NLC in TCM hospitals.

Materials & Methods

A focused ethnographic study was conducted in three TCM hospitals affiliated with Guangzhou University of Chinese Medicine. We interviewed eleven nurses in those hospitals and observed seven of them working with patients. We used snowball sampling for data collection including interview, non‐participant observation and documents from medical records. All the data were processed as following steps: (a) coding for descriptive labels; (b) sorting for patterns; (c) identifying outliers or negative cases; (d) generalizing with construction and theories and (e) noting reflective remarks.

Results

Nurse‐led clinics help nurses develop their skills and knowledge that are highly recognized by public since they meet the growing needs of patients and also relieve the workload of physicians in the hospitals. However, lack of specialization is still a major challenge in NLCs due to insufficiency of full‐time staff with specialized education, nurse‐led practice without standardized guidelines, restrictions on prescription right of nurses, and also inadequate support from hospitals.

Discussions

As a revolutionary innovation of working model for nurses in TCM hospitals, NLCs could improve quality of care and lead to a comprehensive promotion of nursing career. However, there are several challenges on providing high quality care for patients whilst improving educational development of nurses. This study suggests that nurses, hospital administration and the government should cooperate with each other to develop standard nursing programs for NLCs.

Conclusions

It is imperative to identify nursing roles, collect available resources, and develop supportive policies and training programs to enhance the quality of NLCs.
Care home workers experiences of stress and coping during COVID‐19 pandemic: A mixed methods study
Authors: Beattie Michelle , Carolan Clare , Macaden Leah , Maciver Alison , Dingwall Lindsay , Macgilleeathain Rebecah , Schoultz Mariyana
Published: August 2022

Aim

The aim of the study was to explore the stress and coping experiences of healthcare workers (HCWs) in care home settings in Scotland during the COVID‐19 pandemic.

Design

A cross‐sectional mixed methods study was conducted using an online survey and interviews.

Methods

Mean scores were calculated for both stress and coping and t‐tests used to explore possible links to demographics. Qualitative data were analysed thematically using Braun and Clarke's method.

Results

For 52 survey participants, the mean score for the PSS was M = 39.75 and CSE‐M = 150.6 indicating high stress and medium coping skills. From the t‐test, only absence of health issues was associated with higher levels of coping. Thirteen HCWs participated in one‐to‐one interviews. Qualitative data analysis generated four themes contributing to stress: 1. personal factors, 2. changed care environment, 3. amplified scrutiny and 4. psychological responses. Coping was represented as three main themes: 1. personal factors, 2. organizational culture and 3. safety and security. There is a critical need for a strategic approach to provide psychological support to care home staff both during and beyond the context of the pandemic.
Rewilding—The farmers’ perspective. Perceptions and attitudinal support for rewilding among the English farming community
Authors: Mikołajczak Katarzyna M. , Jones Nikoleta , Sandom Christopher J. , Wynne‐Jones Sophie , Beardsall Antonia , Burgelman Suzanna , Ellam Lucy , Wheeler Helen C.
Published: August 2022

Rewilding is an increasingly common conservation approach, aiming to restore ecosystem processes and minimise human intervention. Rewilding has the potential to profoundly change landscapes and people–nature relations. These issues prompt an ongoing debate about how and if rewilding should be done.

Farmers are key stakeholders in this debate; they stand to be both affected by and influence the trajectory of rewilding initiatives developing in the United Kingdom and globally. Despite this, a comprehensive understanding of farmers' perceptions towards rewilding is lacking.

Here, we focus on how members of the farming community in England perceive common rewilding scenarios (beaver release, farm‐level rewilding and landscape‐scale rewilding), and how these perceptions shape farmers' attitudinal support for rewilding practices.

Using thematic analysis of semi‐structured interviews with 36 farmers and farming representatives, we show that the diversity of famers' attitudes can be understood through the prism of perceptions on five core issues: (a) the perceived need for restoration action, (b) the ecological effectiveness of rewilding, (c) rewilding's compatibility with ensuring food security, (d) rewilding's compatibility with rural lifestyles, livelihoods and economies and (e) multidimensional justice of rewilding initiatives. These issues are rooted in collective farming values, and farmers' perceptions of these issues are influenced by mental models, perceived social impacts and perceived ecological outcomes of rewilding initiatives. Diverse perceptions result in a range of attitudes, from enthusiastic support to strong opposition to different rewilding practices.

We argue that the scope to increase support for rewilding varies depending on the type of underlying negative perceptions. Where the negative perceptions are based on objectively verifiable causal beliefs (mental models), opponents' minds may be changed through the provision of positive experiences, social learning, and adhering to good governance principles. However, where negative perceptions are based on values, for example, a preference for traditional rural landscapes, they are unlikely to change easily. Pursuing rewilding ambitions that clash with the values of local farmers may risk social conflicts, but accommodating these values too much may compromise rewilding's own goals. Rewilding initiatives will need dialogue and social engagement to navigate their path around this tension.

Read the free Plain Language Summary for this article on the Journal blog.
Climate change adaptation and adaptive efficacy in the inland fisheries of the Lake Victoria basin
Authors: Nyboer Elizabeth A. , Musinguzi Laban , Ogutu‐Ohwayo Richard , Natugonza Vianny , Cooke Steven J. , Young Nathan , Chapman Lauren J.
Published: August 2022

Inland fisheries support the livelihoods of millions of people in riparian communities worldwide but are influenced by increasing climate variability and change. Freshwater fishing societies are among the most vulnerable to climate change given their dependence on highly threatened aquatic resources. As climate change intensifies, building adaptive capacity within communities and understanding the efficacy of adaptive strategies for maintaining household stability is essential for coping with ongoing social and environmental change.

In this study, we examined household perceptions of climate change, livelihood impacts and responses to socio‐ecological changes in fishing‐dependent households in the Lake Victoria basin in Uganda, East Africa. Through a series of household surveys and focus group discussions in five fish landing sites, we assessed social adaptive capacity (SAC) based on 207 households and identified adaptive strategies that are effective for coping with climatic change.

We found that people in fishing households are aware of environmental change but that most households do not have adaptive strategies that are efficacious for securing long‐term income and food security.

We also investigated household demographics that contribute to SAC, examined links between SAC and adaptive efficacy and established potential routes towards developing effective adaptive approaches in small‐scale fisheries.

This work contributes to a growing foundation of documented community‐based knowledge for building adaptive capacity in inland fisheries and the communities around the world that depend on them.

Read the free Plain Language Summary for this article on the Journal blog.
Comparative study on the mechanical and thermal properties of polycarbonate composites reinforced by KH570/SA/SDBS modified wollastonite fibers
Authors: Chen Feng , Bao Yongzhong , Zhang Jiamin , Yang Ming , Ruan Min , Feng Wei , Jiang Yufeng , Li Ming , Chen Yue
Published: August 2022

In order to increase the applicability of wollastonite (Wo) in polycarbonate (PC) polymer, surface modification of Wo was carried out using different modifiers containing silane coupling agent KH570, stearic acid (SA), and sodium dodecylbenzene sulfonate. The physical, physic‐chemical, and application properties of modified Wo were evaluated. Results showed that KH570 modified Wo had narrower particle size distribution, higher absolute zeta potential and were more evenly distributed. Scanning electron microscope study confirmed their changes in morphology and aspect ratio during the modification process. The tensile strength of Wo/PC composites, in which KH570‐modified Wo was used were superior to those in which original Wo or other modifiers modified samples were used. The maximum tensile strength of 65 ± 1 MPa was obtained by adding 15 wt% KH570‐modified Wo. Thermal analysis indicated that adding Wo to the polycarbonate increased the residue content but decreased the thermal decomposition temperature and glass transition temperature slightly, regardless of unmodified or modified Wo. These results indicated that the well‐modified Wo mineral had the potential to replace expensive carbon and glass fibers as fillers in polycarbonate products.
Simultaneous modification of hydrotalcite–silicate nanolayers as reinforcement of a new polyamide: thermal properties and flammability study
Authors: Hajibeygi Mohsen , Javadi‐gharyesafa Aliasghar
Published: August 2022

New polyamide/clay–layered double hydroxide nanocomposites (PACLN) were prepared from a synthesized aliphatic–aromatic polyamide (AAPA) and organically modified layered double hydroxide–clay (MLC) nanohybrid. MLC was obtained by simultaneous modification of montmorillonite and hydrotalcite nanolayers with cationic–anionic polyethyleneimine/poly(acrylic acid)‐co‐poly(2‐acrylamido‐2‐methylpropanesulfonic acid) in an ion‐exchange reaction. The analysis results indicated that the modification successfully occurred in MLC with increasing interlayer spacing. PACLN were prepared from AAPA and MLC using the solvent‐casting technique. The thermal and combustion properties, morphology and structure of the resulting nanocomposites were studied using thermogravimetric analysis (TGA), microscale combustion calorimetry (MCC), scanning and transmission electron microscopies, Fourier transform infrared spectroscopy and X‐ray diffraction. The results indicated that the silicate and hydrotalcite nanosheets were dispersed in the AAPA matrix. In other words, the silicate and hydrotalcite nanosheets were placed in the AAPA matrix as a new two‐dimensional rearranged structure by self‐assembly. The TGA results of nanocomposites in N2 environment showed that PACLN is more heat resistant than AAPA. The 5% mass degradation temperature of PACLN containing 5 mass% of MLC was obtained as almost 60 °C more than that of AAPA. According to MCC results, the peaks of heat release rate were reduced from 156 to 91 W g−1 for AAPA containing 5 mass% of MLC. © 2022 Society of Industrial Chemistry.
Near‐surface geophysical imaging of a thermokarst pond in the discontinuous permafrost zone in Nunavik (Québec), Canada
Authors: Bussière Léa , Schmutz Myriam , Fortier Richard , Lemieux Jean‐Michel , Dupuy Alain
Published: August 2022

In this study, high resolution ground‐penetrating radar (GPR), electrical resistivity tomography (ERT), and spectral‐induced polarization tomography (SIPT) were used to (i) delineate characteristic solifluction features, (ii) map the ice distribution, and (iii) assess subsurface water content and permeability in the surrounding rampart of a thermokarst pond in the discontinuous permafrost zone. The study site is located in the Tasiapik Valley near Umiujaq in Nunavik (Québec), Canada, which benefits from decades of geological mapping, geophysical investigation, and monitoring of ground temperature and thaw subsidence, providing an extensive understanding of the cryohydrogeological context of the area. The results of geophysical investigation undertaken in this study were cross validated using core sampling, laboratory core analysis, and in situ ground temperature and water content monitoring. Based on this investigation, a conceptual model was derived and compared to the stratigraphy of cross‐section described in literature in finer‐grained context. Very good consistency was found from one in situ geophysical survey to another, as well as between the derived stratigraphic models and the ground truth. The combination of all the available data allowed the development of a detailed cryohydrogeological model across the studied thermokarst pond, which highlights the effect of lithology, topography, and land cover on the distribution and mobility of water in the ground.
A Rate‐Dependent Constitutive Model of HTPB Propellant Based on Parallel Rheological Framework
Authors: Xu Yihang , Li Daokui , Zhou Shiming , Shen Zhibin , Li Yifei
Published: August 2022

Numerous studies have shown that highly strain‐rate dependent behavior is present in the mechanical properties of Hydroxyl‐terminated polybutadiene(HTPB)propellants, and many experts and scholars have attempted to develop constitutive models to describe such rate‐dependent properties of propellants. From the linear viscoelastic model to the Zhu‐Wang‐Tang model, the strain‐rate dependent properties of viscoelastic materials have been described to some extent. But due to the highly nonlinear mechanical behavior exhibited in propellant materials, the nonlinear behavior of propellants at different strain rates is difficult to be captured in the above constitutive models which are all based on linear elasticity. Therefore, in this paper, a nonlinear viscoelastic constitutive model was proposed based on the parallel rheological framework, in which the hyperelastic and viscoelastic flow laws were embedded. Because of the excellent ability to capture the nonlinear behavior of the material, the parallel rheological framework was used to predict the mechanical response at six sets of experiments with different rates. Surprisingly, this constitutive structure model performed good prediction of the mechanical properties of the material by comparison between theoretical calculations and experimental data. The constitutive model was verified by finite element method with numerical simulation software, and the robustness of the constitutive model was checked by a new set of experimental data. A good foundation was established for the accurate description of the propellant constitutive model strain‐rate dependent characteristics by the results of this paper, which could provide a new method for the rapid prediction and evaluation of the propellant mechanical response.
Toxic, cytotoxic and genotoxic effect of plumbagin in the developmental stages of Biomphalaria glabrata (Say, 1818‐intermediate host) and cercaricidal activity against the infectious agent of schistosomiasis mansoni
Authors: França Wilza Wanessa Melo , da Silva Adriana Maria , Diniz Emily Gabriele Marques , Silva Hianna Arely Milca Fagundes , Pereira Dewson Rocha , De Melo Ana Maria Mendonça Albuquerque , Coelho Luana Cassandra Breitenbach Barroso , de Azevedo Albuquerque Mônica Camelo Pessoa , de Araújo Hallysson Douglas Andrade , de Lima Aires André
Published: August 2022

BACKGROUND

Snails of the genus Biomphalaria are intermediate hosts of Schistosoma mansoni, the main etiological agent of schistosomiasis mansoni, which affects about 236.6 million people in tropical and subtropical regions of the world. The World Health Organization recommends the population control of vector snails as one of the strategies to reduce the prevalence and incidence of schistosomiasis. In this study, molluscicidal and antiparasitic activities of plumbagin, a naturally sourced naphthoquinone with a range of biological effects, were evaluated against B. glabrata and cercariae of S. mansoni.

RESULTS

After 24 h of exposure, plumbagin demonstrated molluscicidal activity at low concentrations against embryos (LC50 of 0.56, 0.93, 0.68, 0.51 and 0.74 μg mL−1 for the blastula, gastrula, trochophore, veliger and hippo stage, respectively) and adult snails (LC50 of 3.56 μg mL−1). There were no changes in exposed snails’ fecundity or fertility; however, plumbagin was able to increase the frequency of DNA damage and the number of hemocytes, with apoptosis and binucleation being the main hemocyte alterations. In addition, plumbagin showed death of S. mansoni cercariae in the concentration of 1.5 μg mL−1 in 60 min, while showing moderate toxicity to Artemia salina.

CONCLUSION

Plumbagin proved to be a promising substance for the control of B. glabrata population, intermediate host of S. mansoni, as well as the cercariae, infective stage for humans (definitive host), while being moderately toxic to A. salina, a crustacean widely used in ecotoxicity tests. © 2022 Society of Chemical Industry.
Comparative transcriptome analysis reveals the non‐neuronal cholinergic system in the ovary of the oriental armyworm, Mythimna separata Walker (Lepidoptera: Noctuidae)
Authors: Tian Xing , Guo Jiamin , Su Xinxin , Zhan Baolei , Liang Xiaoyu , Ma Anqi , Zhang Yalin , Lü Shumin
Published: August 2022

BACKGROUND

Acetylcholine (ACh), as a classical neurotransmitter, plays great roles in the nervous system. There is increasing evidence of its non‐neuronal roles in regulating basic cell functions in vertebrates. However, knowledge about the non‐neuronal cholinergic system in insects is scarce.

RESULTS

A comparative transcriptome analysis was performed to investigate differences in the key molecular components of the cholinergic system between the head and ovary. The results showed that expression levels of most cholinergic system‐related genes were higher in the head than in the ovary, and some cholinergic components were absent in the ovary. ACh contents ranged from 0.1 to 1.3 μg mg−1 of wet weight during the development of the ovary, and weak acetylcholinesterase activity was also detected. Moreover, the ovary has a capacity for ACh synthesis. Bromoacetylcarnitine (BrACar), a specific carnitine acetyltransferase (CarAT) inhibitor, greatly inhibits ACh synthesis by 83.83% in ovary homogenates, but bromoacetylcholine (BrACh), a specific choline acetyltransferase (ChAT) inhibitor, has no effect on ACh synthesis in the ovary. These findings indicate that non‐neuronal ACh in the ovary is only catalyzed by CarAT.

CONCLUSION

This study reveals the existence of the non‐neuronal cholinergic system in the ovary of M. separata, whose synthesis and release mechanisms are different from those of the head. These results provide novel insights into the non‐neuronal cholinergic system in insects, and will be valuable in the discovery of new target genes and the future development of green pest control. © 2022 Society of Chemical Industry.
The Effect of Absorber Stoichiometry on the Stability of Widegap (Ag,Cu)(In,Ga)Se2Solar Cells
Authors: Pearson Patrick , Keller Jan , Stolt Lars , Edoff Marika , Platzer Björkman Charlotte
Published: August 2022

(Ag,Cu)(In,Ga)Se2solar cells with bandgaps of ≈1.45 eV with a large spread in absorber stoichiometry are characterized with the intention of assessing the effect of composition on the stability of the devices. This material is observed to have a poor diffusion length, leading to very strong dependence upon the depletion region width for charge carrier collection. The depletion width is observed to depend strongly upon the stoichiometry value and shrinks significantly after an initial period of dark storage. It is also seen that the depletion width can be varied strongly through light‐soaking and dry‐heat treatments, with prolonged annealing leading to detrimental contraction and light soaking leading to expansion which increases current collection. The extent of depletion width variation in response to the treatments is also clearly linked to absorber stoichiometry. Consequently, the device performance, particularly the current output, exhibits a stoichiometry dependence and is considerably affected after each round of treatment. Possible causes of this behavior are discussed.
Constraint‐based analysis of a physics‐guided kinetic energy density expansion
Authors: Aldossari Bader H. , Alenaizan Asem , Al‐Aswad Abdulaziz H. , Alharbi Fahhad H.
Published: August 2022

An approach guided by physical consistency in determining the general forms ofD‐dimensional kinetic energy density functionals (KEDF) has been demonstrated previously, producing an expansion which contains the majority of the known one‐point KEDF forms. It has also been shown that any noninteracting KEDF must necessarily have a homogeneity degree of 2 in coordinate scaling, and that the ratio of the collective KED to electron density must approach the ionization energy as . This article demonstrates that the scaling condition is already satisfied in the general expansion despite not being conceived with the scaling as a constraint, and that the second condition places a restriction on the expansion terms of the KED. The discussion is extended as well for some known KEDs for comparison.
A theoretical investigation ofZnZnandBeBeone electron bond
Authors: Sarmah Kangkan , Kalita Amlan J. , Guha Ankur K.
Published: August 2022

Attachment of one electron to 1,2‐diBeX‐benzene and 1,2‐diZnX‐benzene derivatives leads to the formation of stronger BeBe and ZnZn interaction compared to the neutral one. This is reflected in the dramatic shortening of the BeBe and ZnZn distance. The formation of these 2‐center‐1‐electron bonds have also been confirmed by topological survey of electron density using quantum theory of atoms in molecules and electron localization function. The formation of these bonds is expected to render stability to these radical anions. These radical anions are stable toward electron detachment and computed bond dissociation energy values are also significant.
Hydrophobic microporous extraction on polyurethane sponges for convenient and sensitive analysis of organic molecules in water
Authors: Ji Baocheng , Han Yu , Zhao Wenhao , Yang Lanrui , Xu Xu , Bai Yanhong
Published: August 2022

Rationale

Various solvent supports have been developed to overcome solvent instability during liquid‐phase microextraction. The hydrophobic polyurethane sponge (PS) possesses numerous cross‐linked internal microchannels and terminal micropores that can facilitate steady solvent storage capacity, high extraction efficiency, extractant loading, and recycling convenience.

Methods

In this study, an easy, convenient, and efficient PS‐supported liquid‐phase microextraction (PS‐LPME) coupled with gas chromatography–mass spectrometry (GC–MS) method was developed for the trace analysis of different organic compounds in aqueous solutions. Different extraction solvents, PS dosages, stirring speeds, and extraction times were first investigated by extracting eight polycyclic aromatic hydrocarbons (PAHs: naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, and pyrene), and then applied for the analysis of triazines, amides, chloroacetamides, and organophosphorus compounds.

Results

High enrichment factors (approximately 208–439) were observed for the monitored PAHs. Good linearities, with determination coefficients (r2) greater than 0.9992, were achieved in the concentration range of 0.01–50 μg L−1. Low limits of detection and quantification were found in the ranges of 0.3–3 ng L−1 and 1–10 ng L−1, respectively. At three spiked concentrations (0.1, 1, and 10 μg L−1), good recoveries were obtained in the range of 91.6–118.5% with intra‐ and inter‐day relative standard deviations of less than 6.4% and 11.7%, respectively.

Conclusions

The developed PS‐LPME method coupled with GC–MS was successfully applied in the analysis of different organic compounds in aqueous solutions and has shown great convenience and satisfactory enrichment performance in microextraction analysis.
An ergonomic comfort workspace analysis of master manipulator for robotic laparoscopic surgery with motion scaled teleoperation system
Authors: Kang DongHoon , Kwon Dong‐Soo
Published: August 2022

Background

In robotic surgery, a surgeon controls a surgical robot through a master manipulator in motion scaled teleoperation environment. However, there are no clear criteria for the master's workspace.

Methods

From the user experiment, we proposed an Ergonomic Comfort Workspace considering ergonomics and performed a verification experiment using the actual surgeons' dataset.

Results

From the user experiment, with comfortable posture, there was no significant difference (p‐value < 0.05) between the master workspace when the task space is increased, and the workspace is defined as an ergonomic comfort workspace. Using the JIGSAWS dataset, elementary surgical tasks using surgical robots, verify the effectiveness of the ergonomic comfort workspace (ECW). It was confirmed that more than 95% of surgical task data were almost included in the ECW.

Conclusions

The proposed ECW of the master for robotic laparoscopic surgery enables surgeons to perform surgery with high comfort and precision.
Enclosing ellipsoid‐based reachable set estimation for discrete‐time singular systems
Authors: Zhang Zhihao , Feng Zhiguang
Published: August 2022

This article studies reachable set estimation for discrete‐time singular systems. By means of system decomposition and reconstruction, singular systems can be transformed into dynamic systems together with algebraic equations. Under this representation, two novel reachable set estimation methods based on ellipsoidal sets are proposed under nonzero initial conditions. A series of enclosing ellipsoidal sets can be obtained in two derived methods for bounding real‐time states of the considered systems. Finally, the effectiveness of the proposed methods is illustrated with a numerical example.
Psychological distress and health behaviours among Cambodian Americans at risk for developing diabetes
Authors: Wagner Julie , Bermúdez‐Millán Angela , Berthold S. Megan , Buckley Thomas , Buxton Orfeu M. , Feinn Richard , Kong Sengly , Kuoch Theanvy , Master Lindsay , Scully Mary , Seng Kagnica
Published: August 2022

This paper reports secondary data analysis of associations between psychological distress and health behaviours among Cambodian Americans. Data are from baseline assessments from a diabetes prevention trial. All participants met stucriteria for depression and were free of diabetes. Participants (n = 191) completed surveys, a food frequency assessment, and wore sleep and physical activity actigraphy devices for 7 days. A factor analysis of symptoms of post‐traumatic stress, baksbat (a Cambodian culture‐bound syndrome), depression, and anxiety yielded a single factor named ‘psychological distress’. Multivariate models controlling for psychotropic medications were run for the following outcomes: sleep actigraphy, self‐reported sleep, physical activity actigraphy, self‐reported physical activity, nutrition, and substance use. For actigraphy, higher distress was associated with lower moderate/vigorous physical activity and higher mean variability of 24 h total sleep time. Higher distress was also associated with worse self‐reported sleep quality as indicated by standard, and culturally‐specific, sleep indicators. Higher distress was also associated with lower use of food labels, lower carbohydrate consumption, and higher alcohol consumption as a coping mechanism. Interventions to mitigate diabetes risk in high‐distress populations may benefit from strategies to decrease psychological distress. The sequelae of complex trauma may transcend discrete psychiatric diagnoses.
Probing the Effect of Rigidity on the Cellular Uptake of Core‐Shell Nanoparticles: Stiffness Effects are Size Dependent
Authors: Gurnani Pratik , Sanchez‐Cano Carlos , Xandri‐Monje Helena , Zhang Junliang , Ellacott Sean H. , Mansfield Edward D. H. , Hartlieb Matthias , Dallmann Robert , Perrier Sébastien
Published: August 2022

Nanoparticles are well established vectors for the delivery of a wide range of biomedically relevant cargoes. Numerous studies have investigated the impact of size, shape, charge, and surface functionality of nanoparticles on mammalian cellular uptake. Rigidity has been studied to a far lesser extent, and its effects are still unclear. Here, the importance of this property, and its interplay with particle size, is systematically explored using a library of core‐shell spherical PEGylated nanoparticles synthesized by RAFT emulsion polymerization. Rigidity of these particles is controlled by altering the intrinsic glass transition temperature of their constituting polymers. Three polymeric core rigidities are tested: hard, medium, and soft using two particle sizes, 50 and 100 nm diameters. Cellular uptake studies indicate that softer particles are taken up faster and threefold more than harder nanoparticles with the larger 100 nm particles. In addition, the study indicates major differences in the cellular uptake pathway, with harder particles being internalized through clathrin‐ and caveolae‐mediated endocytosis as well as macropinocytosis, while softer particles are taken up bycaveolae‐ and non‐receptormediated endocytosis. However, 50 nm derivatives do not show any appreciable differences in uptake efficiency, suggesting that rigidity as a parameter in the biological regime may be size dependent.
A Supramolecular Self‐Assembling Nanoagent by Inducing Intracellular Aggregation of PSMA for Prostate Cancer Molecularly Targeted Theranostics
Authors: Zhang Weijie , Wang He , Wang Tianjiao , Ding Dan , Hou Jianquan , Shi Yang , Huang Yuhua
Published: August 2022

Prostate cancer (PCa) with prostate‐specific membrane antigen (PSMA)‐specific high expression is well suited for molecularly targeted theranostics. PSMA expression correlates with the malignancy of PCa, and its dimeric form can promote tumor progression by exerting enzymatic activity to activate downstream signal transduction. However, almost no studies have shown that arresting the procancer signaling of the PSMA receptors themselves can cause tumor cell death. Meanwhile, supramolecular self‐assembling peptides are widely used to design anticancer agents due to their unique and excellent properties. Here, a PSMA‐targeting supramolecular self‐assembling nanotheranostic agent, DBT‐2FFGACUPA, which actively targets PSMA receptors on PCa cell membranes and induces them to enter the cell and form large aggregates, is developed. This process not only selectively images PSMA‐positive tumor cells but also suppresses the downstream procancer signals of PSMA, causing tumor cell death. This work provides an alternative approach and an advanced agent for molecularly targeted theranostics options in PCa that can induce tumor cell death without relying on any reported anticancer drugs.
A Dual‐Function Sensor for Highly Sensitive Detection of Flame and Humidity
Authors: Zhang Zuocai , Lu Tianyun , Yang Dan , Lu Shaorong , Cai Ren , Tan Weihong
Published: August 2022

Early warning sensors rapidly monitor critical temperatures, humidity, and fires, which are crucial to reduce or avoid natural disasters in complex environments, such as fire or water disasters. Here, a highly sensitive, readable, and dual‐functional sensor is designed for a fast‐response fire alarm and rapid humidity detection based on sustainable biological films (named MSCG films). The MSCG films are composed of grafted sisal nanofibers (MgC), silk nanofibers, graphene, and citric acid (CA). After crosslinking with CA, MSCG films exhibit good wet strength (i.e., 128.8 MPa) after soaking in 100 °C water, thus confirming that the films would be applicable to a broad temperature range in humid environments. After flame ignition, the MSCG films are rapidly carbonized to activate an alarm sound and a light in the circuit with a fire response time as short as 1 s. It exhibits ultrafast temperature response/recovery time (i.e., 0.1 s/0.3 s) and rapid humidity response time (i.e., 0.9 s). The dual‐functional sensor is further assembled into a versatile sensor system for real‐time monitoring of fire accidents and environmental humidity, which can be integrated into consumer electronics, such as portable laptops and mobile phones.