bluuebunny/crossref_metadata_2025 huggingface dataset:
Working Memory and Its Mediating Role on the Relationship of Math Anxiety and Math Performance: A Meta-Analysis
Authors: Finell Jonatan , Sammallahti Ellen , Korhonen Johan , Eklöf Hanna , Jonsson Bert
Published: January 2022

It is well established that math anxiety has a negative relationship with math performance (MP). A few theories have provided explanations for this relationship. One of them, the Attentional Control Theory (ACT), suggests that anxiety can negatively impact the attentional control system and increase one's attention to threat-related stimuli. Within the ACT framework, the math anxiety (MA)—working memory (WM) relationship is argued to be critical for math performance. The present meta-analyses provides insights into the mechanisms of the MA—MP relation and the mediating role of WM. Through database searches with pre-determined search strings, 1,346 unique articles were identified. After excluding non-relevant studies, data from 57 studies and 150 effect sizes were used for investigating the MA—MP correlation using a random-effects model. This resulted in a mean correlation of r = −0.168. The database search of WM as a mediator for the MA—MP relation revealed 15 effects sizes leading to a descriptive rather than a generalizable statistic, with a mean indirect effect size of −0.092. Overall, the results confirm the ACT theory, WM does play a significant role in the MA—MP relationship.
Exercise Dependence and Body Image Concerns Amongst Group Fitness Instructors: A Self-Determination Theory Approach
Authors: Reinboth Michael S. , Sundgot-Borgen Jorunn , Bratland-Sanda Solfrid
Published: January 2022

Introduction

Despite the fact that group fitness instructors serve as significant role models with potentially great impact on class participants' motivation for exercise, they are a very under-researched group. The aim of this study was therefore to examine group fitness instructors' motivational regulations for exercise, and how these motivational regulations can predict symptoms of exercise dependence and body image concerns.

Methods

Group fitness instructors from the largest fitness companies in Norway (n = 837, response rate: 57%) completed an online survey with reference to the Situational Motivation Scale (SIMS), the Exercise Dependence Scale (EDS), the Eating Disorders Inventory subscales drive for thinness (EDI-DT) and body dissatisfaction (EDI-BD), and their weekly amount of exercise and instruction.

Results

The instructors scored high on identified regulation and intrinsic regulation for exercise. EDS total score was positively correlated with all SIMS subscales and weekly instruction was positively correlated with Intrinsic regulation. Multiple hierarchical regression analyses found that both self-determined motivational regulations as well as external regulation positively predicted their EDS score. External regulation positively predicted EDI-DT, and EDI-BD.

Conclusion

Group fitness instructors seem highly intrinsically motivated for exercise, which is hypothesized to have a positive impact on group fitness class participants. High self-determined exercise behavior does not seem to buffer against symptoms of exercise dependence within this specific population. There is a need for awareness of group fitness instructors who show high exercise dependency scores due to the link to body image concerns, amotivation and external regulated motivation.
Implementing Introductory Training in Trauma-Informed Care Into Mental Health Rehabilitation Services: A Mixed Methods Evaluation
Authors: Nation Laura , Spence Nicola , Parker Stephen , Wheeler Maddison Paige , Powe Kate , Siew Mei , Nevin Tamara , McKay Michelle , White Michelle , Dark Frances Louise
Published: January 2022

Objective

This paper describes the implementation of training in trauma-informed care (TIC) across a mental health rehabilitation service.

Method

A mixed-methods approach was applied incorporating baseline measures of staff attitudes toward TIC, quantitative description of staff training participation, and semi-structured interviews of Team Leaders' views on the implementation of TIC.

Results

Fifty-five of 123 staff responded to the Organizational Change Readiness Assessment (OCRA) survey (44.7%). Training completion varied considerably between the eight rehabilitation teams (4.8–78%). Analysis of the Team Leader interviews identified four broad themes: The need to respect the person's life journey including the risk of re-traumatization; the importance of considering the context of implementing TIC training; TIC being an essential part of mental health care; and staff may also have trauma histories.

Conclusions

Staff working in mental health rehabilitation are supportive of the need for TIC. The variable training uptake did not reflect the staff comments about the importance of TIC. The burden of adjusting mental health care delivery to COVID-19 restrictions was reported as a major influence on the uptake of training. Systematically implementing training in TIC is required but needs to be complemented by a structured organizational approach to aid embedding this approach into daily mental healthcare delivery.
Perception and Challenges of Preventive Measures of COVID-19 Among Nepalese Frontline Health Professionals: An Unexplored Realism
Authors: Pathak Krishna Prasad , Sanyam Sandip Das , Gaire Tara , Basnet Pushpa Babu , Sah Sanjay Kumar , Basnet Buddha Bahadur , Pathak Sujana , Ingman Stan , Hoffman Jeremy J.
Published: January 2022

Background

A new coronavirus causes COVID-19, a developing respiratory illness. Unfortunately, there is little information assessing healthcare workers' understanding of technology and preventative strategies during the Nepalese epidemic. Researchers from other subspecialties uncovered some mythical thoughts. As a result, we decided to put it to the test with healthcare personnel on the front lines. The research also looked at the problems experienced by frontline health care personnel (HCP) because of the COVID-19 strategic shift in work policy.

Methods

Nepalese healthcare workers participated in web-based cross-sectional research. A pre-tested, structured questionnaire utilizing a Google form was used to get self-informed, digitally typed consent, and examine critical perspectives and problems with current technology and COVID-19 prevention efforts.

Results

In total, 243 participants with mean age of 29.66 ± 7.61 years agreed to participate and were doctors (n = 27), health assistants (n = 2), medical intern doctors (n = 1), paramedical (n = 139), pharmacy (n = 1), and paramedical interns (n = 73) in this study. The calculated mean percentage score of knowledge on instruments and tools was 73.64 (SD ± 10.43) %, and perception on COVID-19 transmission and control was 70.06 (SD ± 18.30) %. At various levels, frontline health workers faced significant challenges, including the adoption of digital health technology.

Conclusion

Frontline HCPs are anticipated to have updated knowledge from what the study has outlined. It is recommended to follow national guidelines. Policies should be put in place so that every frontline worker can demonstrate high standards in prevention, control, and equipment use that do not create misinformation among HCPs. Throughout, support for digital health materials and disease control methods for HCPs is essential.
Genomic Instability in Somatic Hybridization between Poncirus and Citrus Species Aiming to Create New Rootstocks
Authors: Dambier Dominique , Barantin Pascal , Boulard Gabriel , Costantino Gilles , Mournet Pierre , Perdereau Aude , Morillon Raphaël , Ollitrault Patrick
Published: January 2022

Rootstocks are an important component for citrus adaptation to increasing biotic and abiotic stresses resulting from global climate change. There is a strong complementarity between Citrus species, which adapt to abiotic stresses, and Poncirus trifoliata and its intergeneric hybrids, which exhibit resistances or tolerances to major diseases and pests. Thus, symmetrical somatic hybridization between complementary diploid rootstocks of these two genera appears to be an efficient way to develop new tetraploid rootstocks in order to address the new challenges of the citrus industry. New intergeneric somatic hybrids were obtained by electrofusion between protoplasts of Citrus and P. trifoliata hybrids. Extensive characterization of the nuclear and cytoplasmic genomes was performed by genotyping-by-sequencing (GBS) analysis. This revealed diploid cybrids and nuclear somatic hybrids. Mitochondrial genomes were mostly inherited from the callus parent, but homologous recombination events were observed for one parental combination. Chloroplasts exhibited random uniparental inheritance. GBS revealed local chromosomal instabilities for all nuclear somatic hybrids and whole chromosome eliminations for two hybrids. However, at the whole genome level, symmetrical addition of the nuclear genomes of both parents was predominant and all somatic hybrids displayed at least one trifoliate orange haplotype throughout the genome.
Phase Preserving Balanced Truncation for Order Reduction of Positive Real Systems
Authors: Salehi Zeinab , Karimaghaee Paknoosh , Salehi Shabnam , Khooban Mohammad-Hassan
Published: January 2022

This paper presents a new passivity-preserving order reduction method for linear time-invariant passive systems, which are also called positive real (PR) systems, with the aid of the balanced truncation (BT) method. The proposed method stems from the conic positive real balanced truncation (CPRBT) method, which is a modification of the BT method for PR systems. CPRBT presents an algorithm in which the reduced models are obtained from some Riccati equations in which the phase angle of the transfer function has been taken into consideration. Although CPRBT is a powerful algorithm for obtaining accurate PR reduced-order models, it cannot guarantee that the phase diagram of the reduced model remains inside the same interval as that of the original full-order system. We aim to address such a problem by modifying CPRBT in the way that the phase angle of the reduced transfer function always remains inside the conic and homolographic phase interval of the original system. This is proven through some matrix manipulations, which has added mathematical value to the paper. Finally, in order to assess the efficacy of the proposed method, two numerical examples are simulated.
Do We Need to Delineate the Humeral Head in Breast Cancer Patients?
Authors: Belaidi Lahcene , Loap Pierre , Kirova Youlia
Published: January 2022

Humeral heads can be unintentionally exposed during breast radiotherapy, particularly when regional lymph nodes are targeted. Moreover, rotational intensity-modulated radiation therapy techniques, such as helical tomotherapy (HT), increase the low-dose bath, the consequences of which are subject to debate. The aim of this study was to analyze late adverse events involving humeral heads occurring after adjuvant locoregional breast radiotherapy with HT. This single-center retrospective study included 159 breast cancer patients locoregionally irradiated, including the regional lymph nodes, in an adjuvant setting with HT at Institut Curie (Paris, France), between January 2010 and 2016. After a median delay of 48 months, six patients (3.8%) developed localized bone pain, three (1.9%) developed a shoulder functional limitation and one (0.6%) developed a traumatic humeral head fracture. The average mean and maximum doses to humeral heads were 9.18 Gy and 24.41 Gy, respectively, and were not statistically associated with humeral head adverse events. Adverse events were statistically more frequent after mastectomy than after breast-conserving surgery. Berg’s level 1 and 2/3 irradiation, and right-sided radiotherapy were associated with an increased maximum dose. In summary, clinical adverse events were rare, and radiation exposure to humeral heads was low. No correlation was found between dosimetric parameters and late toxicity.
Metabolic Alterations in a Drosophila Model of Parkinson’s Disease Based on DJ-1 Deficiency
Authors: Solana-Manrique Cristina , Sanz Francisco José , Torregrosa Isabel , Palomino-Schätzlein Martina , Hernández-Oliver Carolina , Pineda-Lucena Antonio , Paricio Nuria
Published: January 2022

Parkinson’s disease (PD) is the second-most common neurodegenerative disorder, whose physiopathology is still unclear. Moreover, there is an urgent need to discover new biomarkers and therapeutic targets to facilitate its diagnosis and treatment. Previous studies performed in PD models and samples from PD patients already demonstrated that metabolic alterations are associated with this disease. In this context, the aim of this study is to provide a better understanding of metabolic disturbances underlying PD pathogenesis. To achieve this goal, we used a Drosophila PD model based on inactivation of the DJ-1β gene (ortholog of human DJ-1). Metabolomic analyses were performed in 1-day-old and 15-day-old DJ-1β mutants and control flies using 1H nuclear magnetic resonance spectroscopy, combined with expression and enzymatic activity assays of proteins implicated in altered pathways. Our results showed that the PD model flies exhibited protein metabolism alterations, a shift fromthe tricarboxylic acid cycle to glycolytic pathway to obtain ATP, together with an increase in the expression of some urea cycle enzymes. Thus, these metabolic changes could contribute to PD pathogenesis and might constitute possible therapeutic targets and/or biomarkers for this disease.
The Transcriptional Cell Atlas of Testis Development in Sheep at Pre-Sexual Maturity
Authors: Wu Yi , Guo Tingting , Li Jianye , Niu Chune , Sun Weibo , Zhu Shaohua , Zhao Hongchang , Qiao Guoyan , Han Mei , He Xue , Lu Zengkui , Yuan Chao , Han Jianlin , Liu Jianbin , Yang Bohui , Yue Yaojing
Published: January 2022

Sheep testes undergo a dramatic rate of development with structural changes during pre-sexual maturity, including the proliferation and maturation of somatic niche cells and the initiation of spermatogenesis. To explore this complex process, 12,843 testicular cells from three males at pre-sexual maturity (three-month-old) were sequenced using the 10× Genomics ChromiumTM single-cell RNA-seq (scRNA-seq) technology. Nine testicular somatic cell types (Sertoli cells, myoid cells, monocytes, macrophages, Leydig cells, dendritic cells, endothelial cells, smooth muscle cells, and leukocytes) and an unknown cell cluster were observed. In particular, five male germ cell types (including two types of undifferentiated spermatogonia (Apale and Adark), primary spermatocytes, secondary spermatocytes, and sperm cells) were identified. Interestingly, Apale and Adark were found to be two distinct states of undifferentiated spermatogonia. Further analysis identified specific marker genes, including UCHL1, DDX4, SOHLH1, KITLG, and PCNA, in the germ cells at different states of differentiation. The study revealed significant changes in germline stem cells at pre-sexual maturation, paving the way to explore the candidate factors and pathways for the regulation of germ and somatic cells, and to provide us with opportunities for the establishment of livestock stem cell breeding programs.
Stabilization of Tetrachloride with Mn (II) and Co (II)Complexes and 4-Tert-Butylpyridinium Organic Cation: Elaboration of the Structure and Hirshfeld Surface, Optical, Spectroscopic and Thermal Analyses
Authors: Alotaibi Abdullah A. , Ayari Chaima , Bajuavfir Elham , Ahmad Ashfaq , Al-Nahdi Fatima , Alswieleh Abdullah M. , Alotaibi Khalid M. , Mi Jin-Xiao , Nasr Cherif Ben , Mrad Mohamed Habib
Published: January 2022

[C9H14N]2[MnCl4] (I) and [C9H14N]2[CoCl4] (II) are isostructural compounds produced via gradual evaporation at room temperature. Both compounds consolidate in the tetragonal space group I4¯2d (No. 122), as shown by single-crystal X-ray diffraction observations. A slightly deformed tetrahedral geometry is formed by four chloride atoms around each cation MII (M = Mn or Co). The [C9H14N]+ groups and the isolated [MCl4]2− units are connected via C–H…Cl and N–H…Cl H-bonds to form sheets parallel to the (101¯), (011), (01¯1) and (101) planes. The morphology and the chemical composition of compounds (I) and (II)were determined here using SEM and EDX. The functional groups contained in both compounds were determined using FT-IR spectroscopy. The study of the optical characteristics showed that the two compounds exhibited semiconductor behavior. The thermal analysis (TGA-DTA) was used to determine their thermal stability.
Microplastics Occurrence in the European Common Frog (Rana temporaria) from Cottian Alps (Northwest Italy)
Authors: Pastorino Paolo , Prearo Marino , Di Blasio Alessia , Barcelò Damià , Anselmi Serena , Colussi Silvia , Alberti Silvia , Tedde Giovanni , Dondo Alessandro , Ottino Michele , Pizzul Elisabetta , Renzi Monia
Published: January 2022

Microplastics (MPs) pollution is arousing growing attention, yet knowledge about its occurrence in amphibians is scant to date. With this study, we aimed to determine whether plastic (>5000 μm) and MPs (10–5000 μm) could be detected in adult Rana temporaria from a high-mountain ecosystem (the Cottian Alps, northwest Italy). To do this, aquatic compartments and the digestive tract of adult R. temporaria were analyzed. Water, sediment, periphyton, aquatic macroinvertebrates, and tadpoles tested negative for plastic and MPs. Microplastics were detected in all the adult frogs (n = 5); all the identified items (one per specimen) were fibers (size range: 550.91–2355.51 µm). A statistically significant positive correlation between the particle length and frog size was recorded. The predominant fiber color was blue. The chemical composition was polyamide (60%), polyethylene (20%), and polyethylene terephthalate (20%). Since both the biotic and the abiotic freshwater compartments (tadpoles included) revealed the absence of MPs, it can be assumed that adult frogs ingest MPs from the surrounding terrestrial environment.
Representation Learning for Dynamic Functional Connectivities via Variational Dynamic Graph Latent Variable Models
Authors: Huang Yicong , Yu Zhuliang
Published: January 2022

Latent variable models (LVMs) for neural population spikes have revealed informative low-dimensional dynamics about the neural data and have become powerful tools for analyzing and interpreting neural activity. However, these approaches are unable to determine the neurophysiological meaning of the inferred latent dynamics. On the other hand, emerging evidence suggests that dynamic functional connectivities (DFC) may be responsible for neural activity patterns underlying cognition or behavior. We are interested in studying how DFC are associated with the low-dimensional structure of neural activities. Most existing LVMs are based on a point process and fail to model evolving relationships. In this work, we introduce a dynamic graph as the latent variable and develop a Variational Dynamic Graph Latent Variable Model (VDGLVM), a representation learning model based on the variational information bottleneck framework. VDGLVM utilizes a graph generative model and a graph neural network to capture dynamic communication between nodes that one has no access to from the observed data. The proposed computational model provides guaranteed behavior-decoding performance and improves LVMs by associating the inferred latent dynamics with probable DFC.
Voltage Profiles Improvement in a Power Network with PV Energy Sources—Results of a Voltage Regulator Implementation
Authors: Szultka Agata , Szultka Seweryn , Czapp Stanislaw , Karolak Robert , Andrzejewski Marcin , Kapitaniak Jacek , Kulling Marcin , Bonk Jan
Published: January 2022

The constant increase in the number of photovoltaic (PV) energy sources in distribution networks is the cause of serious voltage problems. The networks built at least a dozen years ago are not provided for the installation of a large number of micro-sources. It happens that the previously properly functioning power networks are not able to provide to consumers power with the required parameters, after installing many PV sources. The problem relates especially to the level of voltage in the networks. This phenomenon sometimes occurs on sunny days, especially in summer. This paper discusses the use of a Low-Voltage Regulator (LVR-sys) in a selected rural distribution network with PV micro-sources. Measured voltage levels in this network, before application and after application of this regulator, are presented. The application of the regulator significantly improved voltage levels in the network and enabled these levels to be maintained within the normative range.
Experimental Studies of Low-Load Limit in a Stoichiometric Micro-Pilot Diesel Natural Gas Engine
Authors: Bonfochi Vinhaes Vinicius , McTaggart-Cowan Gordon , Munshi Sandeep , Shahbakhti Mahdi , Naber Jeffrey D.
Published: January 2022

While operating at light loads, diesel pilot-ignited natural gas engines with lean premixed natural gas suffer from poor combustion efficiency and high methane emissions. This work investigates the limits of low-load operation for a micro-pilot diesel natural gas engine that uses a stoichiometric mixture to enable methane and nitrogen oxide emission control. By optimizing engine hardware, operating conditions, and injection strategies, this study focused on defining the lowest achievable load while maintaining a stoichiometric equivalence ratio and with acceptable combustion stability. A multi-cylinder diesel 6.7 L engine was converted to run natural gas premix with a maximum diesel micro-pilot contribution of 10%. With a base diesel compression ratio of 17.3:1, the intake manifold pressure limit was 80 kPa(absolute). At a reduced compression ratio of 15:1, this limit increased to 85 kPa, raising the minimum stable load. Retarding the combustion phasing, typically used in spark-ignition engines to achieve lower loads, was also tested but found to be limited by degraded diesel ignition at later timings. Reducing the pilot injection pressure improved combustion stability, as did increasing pilot quantity at the cost of lower substitution ratios. The lean operation further reduced load but increased NOx and hydrocarbon emissions. At loads below the practical dual-fuel limit, a transition to lean diesel operation will likely be required with corresponding implications for the aftertreatment system.
Analysis of the Influence of Control Strategy and Heating Loads on the Performance of Hybrid Heat Pump Systems for Residential Buildings
Authors: Roccatello Erica , Prada Alessandro , Baggio Paolo , Baratieri Marco
Published: January 2022

Air-to-water heat pumps (HPs) are widely installed in new buildings; however, they face performance degradation with high temperature emission systems, which is typical of existing buildings, or during domestic hot water (DHW) production. Hybrid systems (HSs), composed by air-to-water HPs and gas-fired boilers, can mitigate these issues by increasing the overall system efficiency. HS performance is strictly dependent on the configuration and control management of the system itself. Moreover, the building and heating plant also have a strong influence. This study presents an overview of the application of HSs that considers both space heating (SH) and DHW production, by comparing the primary energy (PE) consumption obtained by dynamic simulations. Different climates, building typologies, and DHW withdrawal profiles are used to extend the results’ validity. Additionally, several HS control strategies were implemented and compared. The results show a PE savings ranging from 5% to 22% depending on the control strategy and the external parameters applied in the simulation. The comparison of the control strategies shows that the most efficient strategies are the ones maximizing heat pump utilization. The dependence of PE savings of HS on COP values is highlighted, and a correlation is presented to provide designers with guidance on the applicability of HSs.
Superior Electrochemical Performance of Two-Dimensional RGO/Cu/Cu2O Composite as Anode Material for Lithium-Ion Batteries
Authors: Hameed Muhammad Usman , Bocchetta Patrizia , Shahida Shabnam , Altaf Faizah , Ahmed Ashfaq , Majid Khan Abdul
Published: January 2022

In recent years, graphene has attracted the interest of many researchers working on LIB anode materials owing to its unique 2D structure, thermal stability, and fast electron transfer. In this work, RGO/Cu/Cu2O nanocomposites were synthesized through a hydrothermal procedure. The as-prepared nanocomposites exhibited a high lithium storage capacity with improved cycling stability and great rate performance, i.e., the discharge capacity was 371.8 mAh/g after 100 cycles at a current density of 500 mA/g. These excellent properties were associated with the sheet structure symmetry of graphene enriched with the multifunctional Cu-Cu2O component, which prevented aggregation and accommodated the volume changes of the anode material during the charge–discharge tests. The RGO/Cu/Cu2O composite conferred to the LIB anode the ability to resist electrode cracking. The approach proposed in this paper can be also generalized for the synthesis of other carbon-based anode materials for LIBs.
An Active Path-Associated Cache Scheme for Mobile Scenes
Authors: Zhou Tianchi , Sun Peng , Han Rui
Published: January 2022

With the widespread growth of mass content, information-centric networks (ICN) have become one of the research hotspots of future network architecture. One of the important features of ICN is ubiquitous in-network caching. In recent years, the explosive growth of mobile devices has brought content dynamics, which poses a new challenge to the original ICN caching mechanism. This paper focuses on the WiFi mobile scenario of ICN. We design a new path-associated active caching scheme to shorten the time delay of users obtaining content to enhance the user experience. In this article, based on the WiFi scenario, we first propose a solution for neighbor access point selection from a theoretical perspective, considering the caching cost and transition probability. The cache content is then forwarded based on the selected neighbor set. For cached content, we propose content freshness according to mobile characteristics and consider content popularity at the same time. For cache nodes, we focus on the size of the remaining cache space and the number of hops from the cache to the user. We have implemented this strategy based on the value of caching on the forwarding path. The simulation results show that our caching strategy has a significant improvement in performance compared with active caching and other caching strategies.
Research on Frequent Itemset Mining of Imaging Genetics GWAS in Alzheimer’s Disease
Authors: Liang Hong , Cao Luolong , Gao Yue , Luo Haoran , Meng Xianglian , Wang Ying , Li Jin , Liu Wenjie
Published: January 2022

As an efficient method, genome-wide association study (GWAS) is used to identify the association between genetic variation and pathological phenotypes, and many significant genetic variations founded by GWAS are closely associated with human diseases. However, it is not enough to mine only a single marker effect variation on complex biological phenotypes. Mining highly correlated single nucleotide polymorphisms (SNP) is more meaningful for the study of Alzheimer's disease (AD). In this paper, we used two frequent pattern mining (FPM) framework, the FP-Growth and Eclat algorithms, to analyze the GWAS results of functional magnetic resonance imaging (fMRI) phenotypes. Moreover, we applied the definition of confidence to FP-Growth and Eclat to enhance the FPM framework. By calculating the conditional probability of identified SNPs, we obtained the corresponding association rules to provide support confidence between these important SNPs. The resulting SNPs showed close correlation with hippocampus, memory, and AD. The experimental results also demonstrate that our framework is effective in identifying SNPs and provide candidate SNPs for further research.
HIV, Tuberculosis, and Food Insecurity in Africa—A Syndemics-Based Scoping Review
Authors: Ojo Temitope , Ruan Christina , Hameed Tania , Malburg Carly , Thunga Sukruthi , Smith Jaimie , Vieira Dorice , Snyder Anya , Tampubolon Siphra Jane , Gyamfi Joyce , Ryan Nessa , Lim Sahnah , Santacatterina Michele , Peprah Emmanuel
Published: January 2022

The double burden of HIV/AIDS and tuberculosis (TB), coupled with endemic and problematic food insecurity in Africa, can interact to negatively impact health outcomes, creating a syndemic. For people living with HIV/AIDS (PWH), food insecurity is a significant risk factor for acquiring TB due to the strong nutritional influences and co-occurring contextual barriers. We aim to synthesize evidence on the syndemic relationship between HIV/AIDS and TB co-infection and food insecurity in Africa. We conducted a scoping review of studies in Africa that included co-infected adults and children, with evidence of food insecurity, characterized by insufficient to lack of access to macronutrients. We sourced information from major public health databases. Qualitative, narrative analysis was used to synthesize the data. Of 1072 articles screened, 18 articles discussed the syndemic effect of HIV/AIDS and TB co-infection and food insecurity. Reporting of food insecurity was inconsistent, however, five studies estimated it using a validated scale. Food insecure co-infected adults had an average BMI of 16.5–18.5 kg/m2. Negative outcomes include death (n = 6 studies), depression (n = 1 study), treatment non-adherence, weight loss, wasting, opportunistic infections, TB-related lung diseases, lethargy. Food insecurity was a precursor to co-infection, especially with the onset/increased incidence of TB in PWH. Economic, social, and facility-level factors influenced the negative impact of food insecurity on the health of co-infected individuals. Nutritional support, economic relief, and psychosocial support minimized the harmful effects of food insecurity in HIV–TB populations. Interventions that tackle one or more components of a syndemic interaction can have beneficial effects on health outcomes and experiences of PWH with TB in Africa.
Pan-Cancer Prediction of Cell-Line Drug Sensitivity Using Network-Based Methods
Authors: Pouryahya Maryam , Oh Jung Hun , Mathews James C. , Belkhatir Zehor , Moosmüller Caroline , Deasy Joseph O. , Tannenbaum Allen R.
Published: January 2022

The development of reliable predictive models for individual cancer cell lines to identify an optimal cancer drug is a crucial step to accelerate personalized medicine, but vast differences in cancer cell lines and drug characteristics make it quite challenging to develop predictive models that result in high predictive power and explain the similarity of cell lines or drugs. Our study proposes a novel network-based methodology that breaks the problem into smaller, more interpretable problems to improve the predictive power of anti-cancer drug responses in cell lines. For the drug-sensitivity study, we used the GDSC database for 915 cell lines and 200 drugs. The theory of optimal mass transport was first used to separately cluster cell lines and drugs, using gene-expression profiles and extensive cheminformatic drug features, represented in a form of data networks. To predict cell-line specific drug responses, random forest regression modeling was separately performed for each cell-line drug cluster pair. Post-modeling biological analysis was further performed to identify potential biological correlates associated with drug responses. The network-based clustering method resulted in 30 distinct cell-line drug cluster pairs. Predictive modeling on each cell-line-drug cluster outperformed alternative computational methods in predicting drug responses. We found that among the four drugs top-ranked with respect to prediction performance, three targeted the PI3K/mTOR signaling pathway. Predictive modeling on clustered subsets of cell lines and drugs improved the prediction accuracy of cell-line specific drug responses. Post-modeling analysis identified plausible biological processes associated with drug responses.
From Marine Metabolites to the Drugs of the Future: Squalamine, Trodusquemine, Their Steroid and Triterpene Analogues
Authors: Kazakova Oxana , Giniyatullina Gulnara , Babkov Denis , Wimmer Zdenek
Published: January 2022

This review comprehensively describes the recent advances in the synthesis and pharmacological evaluation of steroid polyamines squalamine, trodusquemine, ceragenins, claramine, and their diverse analogs and derivatives, with a special focus on their complete synthesis from cholic acids, as well as an antibacterial and antiviral, neuroprotective, antiangiogenic, antitumor, antiobesity and weight-loss activity, antiatherogenic, regenerative, and anxiolytic properties. Trodusquemine is the most-studied small-molecule allosteric PTP1B inhibitor. The discovery of squalamine as the first representative of a previously unknown class of natural antibiotics of animal origin stimulated extensive research of terpenoids (especially triterpenoids) comprising polyamine fragments. During the last decade, this new class of biologically active semisynthetic natural product derivatives demonstrated the possibility to form supramolecular networks, which opens up many possibilities for the use of such structures for drug delivery systems in serum or other body fluids.
Cannabidiol Treatment Improves Glucose Metabolism and Memory in Streptozotocin-Induced Alzheimer’s Disease Rat Model: A Proof-of-Concept Study
Authors: de Paula Faria Daniele , Estessi de Souza Larissa , Duran Fabio Luis de Souza , Buchpiguel Carlos Alberto , Britto Luiz Roberto , Crippa José Alexandre de Souza , Filho Geraldo Busatto , Real Caroline Cristiano
Published: January 2022

An early and persistent sign of Alzheimer’s disease (AD) is glucose hypometabolism, which can be evaluated by positron emission tomography (PET) with 18F-2-fluoro-2-deoxy-D-glucose ([18F]FDG). Cannabidiol has demonstrated neuroprotective and anti-inflammatory properties but has not been evaluated by PET imaging in an AD model. Intracerebroventricular (icv) injection of streptozotocin (STZ) is a validated model for hypometabolism observed in AD. This proof-of-concept study evaluated the effect of cannabidiol treatment in the brain glucose metabolism of an icv-STZ AD model by PET imaging. Wistar male rats received 3 mg/kg of STZ and [18F]FDG PET images were acquired before and 7 days after STZ injection. Animals were treated with intraperitoneal cannabidiol (20 mg/kg—STZ–cannabidiol) or saline (STZ–saline) for one week. Novel object recognition was performed to evaluate short-term and long-term memory. [18F]FDG uptake in the whole brain was significantly lower in the STZ–saline group. Voxel-based analysis revealed a hypometabolism cluster close to the lateral ventricle, which was smaller in STZ–cannabidiol animals. The brain regions with more evident hypometabolism were the striatum, motor cortex, hippocampus, and thalamus, which was not observed in STZ–cannabidiol animals. In addition, STZ–cannabidiol animals revealed no changes in memory index. Thus, this study suggests that cannabidiol could be an early treatment for the neurodegenerative process observed in AD.
FLS2–RBOHD–PIF4 Module Regulates Plant Response to Drought and Salt Stress
Authors: Liu Zhixin , Guo Chenxi , Wu Rui , Hu Yunhe , Zhou Yaping , Wang Jiajing , Yu Xiaole , Zhang Yixin , Bawa George , Sun Xuwu
Published: January 2022

As sessile organisms, plants are constantly challenged by several environmental stresses. Different kinds of stress often occur simultaneously, leading to the accumulation of reactive oxygen species (ROS) produced by respiratory burst oxidase homolog (RBOHD) and calcium fluctuation in cells. Extensive studies have revealed that flagellin sensitive 2 (FLS2) can sense the infection by pathogenic microorganisms and activate cellular immune response by regulating intracellular ROS and calcium signals, which can also be activated during plant response to abiotic stress. However, little is known about the roles of FLS2 and RBOHD in regulating abiotic stress. In this study, we found that although the fls2 mutant showed tolerance, the double mutant rbohd rbohf displayed hypersensitivity to abiotic stress, similar to its performance in response to immune stress. An analysis of the transcriptome of the fls2 mutant and rbohd rbohf double mutant revealed that phytochrome interacting factor 4 (PIF4) acted downstream of FLS2 and RBOHD to respond to the abiotic stress. Further analysis showed that both FLS2 and RBOHD regulated the response of plants to drought and salt stress by regulating the expression of PIF4. These findings revealed an FLS2–RBOHD–PIF4 module in regulating plant response to biotic and abiotic stresses.
Reduction in Ventilation-Induced Diaphragmatic Mitochondrial Injury through Hypoxia-Inducible Factor 1α in a Murine Endotoxemia Model
Authors: Li Li-Fu , Yu Chung-Chieh , Wu Huang-Pin , Chu Chien-Ming , Huang Chih-Yu , Liu Ping-Chi , Liu Yung-Yang
Published: January 2022

Mechanical ventilation (MV) is essential for patients with sepsis-related respiratory failure but can cause ventilator-induced diaphragm dysfunction (VIDD), which involves diaphragmatic myofiber atrophy and contractile inactivity. Mitochondrial DNA, oxidative stress, mitochondrial dynamics, and biogenesis are associated with VIDD. Hypoxia-inducible factor 1α (HIF-1α) is crucial in the modulation of diaphragm immune responses. The mechanism through which HIF-1α and mitochondria affect sepsis-related diaphragm injury is unknown. We hypothesized that MV with or without endotoxin administration would aggravate diaphragmatic and mitochondrial injuries through HIF-1α. C57BL/6 mice, either wild-type or HIF-1α-deficient, were exposed to MV with or without endotoxemia for 8 h. MV with endotoxemia augmented VIDD and mitochondrial damage, which presented as increased oxidative loads, dynamin-related protein 1 level, mitochondrial DNA level, and the expressions of HIF-1α and light chain 3-II. Furthermore, disarrayed myofibrils; disorganized mitochondria; increased autophagosome numbers; and substantially decreased diaphragm contractility, electron transport chain activities, mitofusin 2, mitochondrial transcription factor A, peroxisome proliferator activated receptor-γ coactivator-1α, and prolyl hydroxylase domain 2 were observed (p < 0.05). Endotoxin-stimulated VIDD and mitochondrial injuries were alleviated in HIF-1α-deficient mice (p < 0.05). Our data revealed that endotoxin aggravated MV-induced diaphragmatic dysfunction and mitochondrial damages, partially through the HIF-1α signaling pathway.
Vesicle Fusion as a Target Process for the Action of Sphingosine and Its Derived Drugs
Authors: Villanueva José , Gimenez-Molina Yolanda , Davletov Bazbek , Gutiérrez Luis M.
Published: January 2022

The fusion of membranes is a central part of the physiological processes involving the intracellular transport and maturation of vesicles and the final release of their contents, such as neurotransmitters and hormones, by exocytosis. Traditionally, in this process, proteins, such SNAREs have been considered the essential components of the fusion molecular machinery, while lipids have been seen as merely structural elements. Nevertheless, sphingosine, an intracellular signalling lipid, greatly increases the release of neurotransmitters in neuronal and neuroendocrine cells, affecting the exocytotic fusion mode through the direct interaction with SNAREs. Moreover, recent studies suggest that FTY-720 (Fingolimod), a sphingosine structural analogue used in the treatment of multiple sclerosis, simulates sphingosine in the promotion of exocytosis. Furthermore, this drug also induces the intracellular fusion of organelles such as dense vesicles and mitochondria causing cell death in neuroendocrine cells. Therefore, the effect of sphingosine and synthetic derivatives on the heterologous and homologous fusion of organelles can be considered as a new mechanism of action of sphingolipids influencing important physiological processes, which could underlie therapeutic uses of sphingosine derived lipids in the treatment of neurodegenerative disorders and cancers of neuronal origin such neuroblastoma.
Protein-Mediated Transformations of Superparamagnetic Nanoparticles Evidenced by Single-Particle Inductively Coupled Plasma Tandem Mass Spectrometry: A Disaggregation Phenomenon
Authors: Sikorski Jacek , Matczuk Magdalena , Kamińska Agnieszka , Kruszewska Joanna , Trzaskowski Maciej , Timerbaev Andrei R. , Jarosz Maciej
Published: January 2022

Progress toward translating superparamagnetic iron oxide nanoparticles (SPIONs) with specific diagnostic and therapeutic properties for clinical applications depends on developing and implementing appropriate methodologies that would allow in-depth characterizations of their behavior in a real biological environment. Herein, we report a versatile approach for studying interactions between SPIONs and proteins using single-particle inductively coupled plasma tandem mass spectrometry. By monitoring the changes in the size distribution upon exposure to human serum, the formation of stable protein corona is revealed, accompanied by particle disaggregation.
Structural, Optical and Mechanical Properties of Nanocrystalline Molybdenum Thin Films Deposited under Variable Substrate Temperature
Authors: Makeswaran Nanthakishore , Orozco Cristian , Battu Anil K. , Deemer Eva , Ramana C. V.
Published: January 2022

Molybdenum (Mo), which is one among the refractory metals, is a promising material with a wide variety of technological applications in microelectronics, optoelectronics, and energy conversion and storage. However, understanding the structure–property correlation and optimization at the nanoscale dimension is quite important to meet the requirements of the emerging nanoelectronics and nanophotonics. In this context, we focused our efforts to derive a comprehensive understanding of the nanoscale structure, phase, and electronic properties of nanocrystalline Mo films with variable microstructure and grain size. Molybdenum films were deposited under varying temperature (25–500 °C), which resulted in Mo films with variable grain size of 9–22 nm. The grazing incidence X-ray diffraction analyses indicate the (110) preferred growth behavior the Mo films, though there is a marked decrease in hardness and elastic modulus values. In particular, there is a sizable difference in maximum and minimum elastic modulus values; the elastic modulus decreased from ~460 to 260–280 GPa with increasing substrate temperature from 25–500 °C. The plasticity index and wear resistance index values show a dramatic change with substrate temperature and grain size. Additionally, the optical properties of the nanocrystalline Mo films evaluated by spectroscopic ellipsometry indicate a marked dependence on the growth temperature and grain size. This dependence on grain size variation was particularly notable for the refractive index where Mo films with lower grain size fell in a range between ~2.75–3.75 across the measured wavelength as opposed to the range of 1.5–2.5 for samples deposited at temperatures of 400–500 °C, where the grain size is relatively higher. The conductive atomic force microscopy (AFM) studies indicate a direct correlation with grain size variation and grain versus grain boundary conduction; the trend noted was improved electrical conductivity of the Mo films in correlation with increasing grain size. The combined ellipsometry and conductive AFM studies allowed us to optimize the structure–property correlation in nanocrystalline Mo films for application in electronics and optoelectronics.
Influence of Laser Beam Power on Microstructure and Microhardness of Fe/ZrC Coatings Produced on Steel Using Laser Processing—Preliminary Study on the Single Laser Tracks
Authors: Bartkowski Dariusz
Published: January 2022

This paper presents preliminary tests of the parameter analysis of the Fe/ZrC coatings production process and the obtained properties. The effects of laser beam power on the obtained microstructure, chemical composition and microhardness were investigated. The tests consisted of the production of composite coatings by laser processing of initial coatings made in the form of a paste on a steel substrate. During the tests, a diode laser with a rated power of 3 kW was used. The laser processing process was carried out using a constant scanning speed laser beam of 3 m/min and four different powers of the laser beam: 500 W, 700 W, 900 W, 1100 W. It was found that it is possible to create composite coatings on a steel surface, where the matrix is made of iron-based alloy and the reinforcing phase is ZrC carbide. It was also found that reinforcing phase content decreased as laser beam power increased. A similar relationship was found for microhardness. As laser beam power increases, the microhardness of the iron-based matrix decreases, finally reaching a value lower than the heat-affected zone. It was found that the amount of hard carbide phases in the iron-based matrix affects the total hardness of the coatings. Presented study concern Fe/ZrC coatings that have not previously been produced on steel by laser processing of precoating, which may be a new contribution in the field of metal surface engineering.
The Three-Level Elastoviscoplastic Model and Its Application to Describing Complex Cyclic Loading of Materials with Different Stacking Fault Energies
Authors: Trusov Peter Valentinovich , Gribov Dmitriy Sergeevich
Published: January 2022

The development of new technologies for thethermomechanical processing of metals and the improvement of the existing ones would be unattainable without the use of mathematical models. The physical and mechanical properties of alloys and the performance characteristics of the products made of these alloys are generally determined by the microstructure of materials. In real manufacturing processes, the deformation of metals and alloys occurs when they undergo complex (non-proportional) loading. Under these conditions, the formation of defect substructures, which do not happen at simple (proportional) loading, can take place. This is due to the occurrence of a great number of slip systems activated under loading along complex strain paths, which leads, for instance, to the more intense formation of barriers of different types, including barriers on split dislocations. In these processes, the formation and annihilation of dislocations proceed actively. In this paper, we present a three-level mathematical model that is based on an explicit description of the evolution dislocations density and the formation of dislocations barriers. The model is intended for the description of arbitrary complex loads with an emphasis on complex cyclic deformation.The model is composed of macrolevel (a representative macrovolume of the material that can be considered as an integration point in the finite-element modeling of real constructions), and mesolevel-1 (description of the mechanical response of a crystallite) and mesolevel-2 (description of the defect structure evolution in a crystallite) submodels. Using the model, we have performed a series of numerical experiments on simple and complex, monotonic and cyclic deformations of materials with different stacking fault energies, analyzed the evolution of defect densities, and analyzed the challenges of a relationship between the complexity of loading processes at a macrolevel and the activation of slip systems at low scale levels.