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Entire solutions to Fermat-type difference and partial differential-difference equations in C^n
No full textIn this article, we study the existence and the form of finite order transcendental entire solutions of systems of Fermat-type difference and partial differential-difference equations in several complex variables. Our results extend previous theorems given by Xu-Cao [49], Xu et al [52], and Zheng-Xu [55]. We give some examples to illustrate the content of this article.Mathematic
Impact of vaccination and sterilization on the transmission dynamics of rabies
No full textWe construct a mathematical model by dividing the dog and human populations into eight compartments as the rabies virus is likely to spread in both populations. In the model, disease-controlling strategies such as vaccination, sterilization and culling are taken into consideration, and their impact is studied. The current study assumes that dogs can transmit rabies among dogs as well as to human population. We apply the next-generation matrix technique to compute the basic reproduction number. Also, each parameters involved are subjected to sensitivity analysis using the approach of normalized sensitivity index. The rabies-free and endemic-equilibrium points are discovered analytically, demonstrating that it is asymptotically steady locally. The numerical simulations, which use approximations for parameter values, shows that effective method for controlling rabies transmission is a combination of vaccination, sterilization and culling of infected dogs. The findings indicate that the annual dog birth rate is also a critical factor in affecting the rabies virus spread.Mathematic
Structural Behavior of Circular Concrete Columns Reinforced with Longitudinal GFRP Rebars under Axial Load
No full textThis paper presents experimental and theoretical assessments of the structural behavior of circular steel fiber-reinforced concrete (SFRC) columns reinforced with glass fiber-reinforced polymer (GFRP) bars subjected to a concentric axial compressive load. Laboratory experiments were planned to evaluate and compare the effect of different design parameters on the structural behavior of column specimens based on experiments and finite element (FE) analysis. The experimental variables were (i) concrete types, i.e., conventional concrete (CC) and fiber-reinforced concrete (FC), (ii) longitudinal reinforcement types, i.e., steel and GFRP bars, and (iii) transverse rebar configurations, i.e., tied and spiral with different pitches. Sixteen column specimens were fabricated and categorized into four groups with respect to rebar configurations and concrete types. The results showed that the failure modes and cracking patterns of those four column groups were comparable, particularly in the pre-peak branches of load-deflection curves. Even though the average ultimate load of the columns with longitudinal GFRP bars was 17.9% less than that with longitudinal steel bars, the ductility index (DI) was 10.2% greater than their counterpart on average. The addition of steel fibers (SF) to concrete increased the axial peak load by up to 3.1% and the DI by up to 6.6% compared to their counterpart CC columns without SFs. The DI of specimens was increased by higher volumetric ratios (up to 12%) and spiral types (up to 5.5%). The concrete damage plastic (CDP) model for FC columns was updated in the finite element software ABAQUS 6.14. Finally, a new simple equation was theoretically proposed to predict the axial capacity of specimens by considering the inclusion of longitudinal GFRP rebars, volumetric ratio, and steel spiral/hoop ties. Good agreement between the proposed model predictions and the experimental/numerical results was observed.Engineerin
Cancer Cell Biomechanical Properties Accompany Tspan8-Dependent Cutaneous Melanoma Invasion
No full textThe intrinsic biomechanical properties of cancer cells remain poorly understood. To decipher whether cell stiffness modulation could increase melanoma cells’ invasive capacity, we performed both in vitro and in vivo experiments exploring cell stiffness by atomic force microscopy (AFM). We correlated stiffness properties with cell morphology adaptation and the molecular mechanisms underlying epithelial-to-mesenchymal (EMT)-like phenotype switching. We found that melanoma cell stiffness reduction was systematically associated with the acquisition of invasive properties in cutaneous melanoma cell lines, human skin reconstructs, and Medaka fish developing spontaneous MAP-kinase-induced melanomas. We observed a systematic correlation of stiffness modulation with cell morphological changes towards mesenchymal characteristic gains. We accordingly found that inducing melanoma EMT switching by overexpressing the ZEB1 transcription factor, a major regulator of melanoma cell plasticity, was sufficient to decrease cell stiffness and transcriptionally induce tetraspanin-8-mediated dermal invasion. Moreover, ZEB1 expression correlated with Tspan8 expression in patient melanoma lesions. Our data suggest that intrinsic cell stiffness could be a highly relevant marker for human cutaneous melanoma development.Xiphophorus Genetic Stock Cente
Piezoelectric Energy Harvesting for Civil Engineering Applications
No full textThis work embarks on an exploration of piezoelectric energy harvesting (PEH), seeking to unravel its potential and practicality. PEH has emerged as a promising technology in the field of civil engineering, offering a sustainable approach to generating energy from ambient mechanical vibrations. We will explore the applications and advancements of PEH within the realm of civil engineering, focusing on publications, especially from the years 2020 to 2024. The purpose of this study is to thoroughly examine the potential and practicality of PEH in civil engineering applications. It delves into the fundamental principles of energy conversion and explores its use in various areas, such as roadways, railways, bridges, buildings, ocean wave-based energy harvesting, structural health monitoring, and even extraterrestrial settings. Despite the potential benefits of PEH in these domains, there are significant challenges that need to be addressed. These challenges include inefficient energy conversion, limitations in scalability, concerns regarding durability, and issues with integration. This review article aims to address these existing challenges and the research gap in the piezoelectric field.Engineerin
Updating Chimpanzee Nesting Data at Mount Assirik (Niokolo Koba National Park, Senegal): Implications for Conservation
No full textThe Niokolo Koba National Park (NKNP) is the largest protected area in Senegal and lies at the northern limit of the chimpanzee’s range in West Africa. Recent information on nesting behavior and factors influencing nesting behavior is available for several sites outside NKNP. However, the information available for NKNP is obsolete. Considering that the adequate management of chimpanzee populations cannot be achieved without strong scientific knowledge, it is essential to update data on chimpanzee, Pan troglodytes verus, nesting behavior in NKNP. For this reason, we surveyed their habitat in Mt. Assirik and recorded 626 chimpanzee nests. The results of the study showed that chimpanzees nest more often in closed-canopy habitats such as gallery forests. The average nest height observed in this study was 8.07 ± 0.36 m, varying between 2 and 20 m, which is well below the heights described in most sites where chimpanzees cohabit with large carnivores. Botanical surveys confirmed that chimpanzees select tree species bearing their nests. In Assirik, 12 of the 37 tree species bearing nests are the most used. The nest decay rate (or the time it takes for a nest to go from the fresh to the skeletal stage) at Assirik averaged 68.8 ± 5.8 days.Anthropolog
An Exploratory Analysis of the Association between Healthcare Associated Infections and Hospital Financial Performance
No full textPurpose: Healthcare-associated infections (HAIs) place a significant financial burden on United States hospitals. HAI treatments extend hospital lengths of stay and increase hospital operational costs while significantly reducing hospital profit margins. Given these challenges, the research aim of this study was to explore the association between HAIs and hospital financial performance. A better understanding of this relationship can assist hospital leaders in optimizing the use of scarce financial resources to reduce HAI prevalence. Methods: Data for calendar year 2022 for active short-term acute care hospitals (n = 1454) in the US were analyzed using multiple linear regression analysis. We explored two derived dependent variables, operating expense per staffed bed and operating expense per discharge. The independent variables included four healthcare-associated infection rates: methicillin-resistant Staphylococcus aureus (MRSA) infection rate, Clostridium difficile (C. diff) infection rate, Catheter-Associated Urinary Tract Infection (CAUTI) rate, and Central Line Associated Blood Stream Infections (CLABSI). Appropriate organizational and market-level variables that may independently influence hospital financial performance were included as control variables. Results: The results revealed that C. diff (β: 0.037, p < 0.05) and CAUTI (β: 0.031, p < 0.05) rates were positively associated with an increase in operating expense per staffed bed, while increases in MRSA (β: 0.042, p < 0.001), C. diff (β: 0.062, p < 0.001), and CAUTI rates (β: 0.039, p < 0.001) were correlated with increased operating expenses per discharge. Conclusions: This study demonstrates that specific HAIs may be associated with increased hospital expenses. Proactively targeting these infections through tailored interventions may lead to reduced hospital costs, improved financial performance, and economic stability.Health AdministrationHealth Informatics and Information Managemen
Seafood Purchasing Behavior in the U.S. during the Early Recovery Period from the COVID-19 Pandemic
No full textThis study examined seafood consumption during the early period of economic recovery following the COVID-19 pandemic. Specifically, surveys of U.S. consumers compared seafood purchasing behavior of the first two quarters of 2021 (Q1, 1 January through 31 March 2021, and Q2, 1 April through 30 June 2021) with those of 2020. Each survey included 100 seafood consumer respondents in each of the 20 U.S. metropolitan market areas. Following data cleaning, there were 1885 valid responses for Q1-2021 and 1940 for Q2-2021. A majority (57%) of respondents had received at least one dose of the COVID-19 vaccine before March 2021 and 70% had received at least one dose as of June 2021. Regardless of vaccination status, few respondents (6% to 9.5% for food generally and 4% to 6.5% for seafood) reported changes in seafood consumption. Seafood consumption away from home increased significantly in Q1-2021 as compared to 2020 and continued to increase but to a lesser degree in Q2-2021. Demographic differences were found in shopping behaviors by age, education, income, and gender, but not by ethnic group. Generally, higher-income females with higher education tended to purchase more seafood. Respondents reported increased numbers of shopping trips per year in Q1-2021 as compared to 2020, which continued into Q2-2021 for general food, but shopping trips for seafood decreased as compared to 2020. The frequency of takeout purchases (times/year) of prepared meals for home consumption of seafood decreased during Q1 from 2020 and remained at that level in Q2-2021, but home delivery purchases of prepared meals of seafood increased during this period. Approximately 50–55% of respondents reported no change in overall seafood consumption levels, while 28% noted an increase in seafood consumption compared to pre-pandemic periods, a significant increase from the 19% who had reported doing so pre-pandemic. In contrast, those reporting a decrease declined from 31% to 17% in comparison to pre-pandemic levels. Seafood consumption in the U.S. remained stable and recovered in early 2021, with a preference for dining out. Consumer behaviors varied by age, income, education, and gender, but not by ethnicity. These changes were primarily driven by access, availability, and income, indicating the need for further research on long-term consumption patterns. This study found apparent stability of seafood consumption by U.S. consumers, which recovered from pandemic consumption levels in early 2021, and there was little change in seafood consumption, frequency, or the types of seafood consumed. Vaccination status did not appear to affect seafood consumption.Agricultural Science
Molecular mechanism of the interplay between human BRCA1-BARD1 and DNA/RNA helicase ZGRF1 in R-loop resolution and genome maintenance
No full textR-loops form upon hybridization of RNA with a complementary strand in duplex DNA. R-loops are a major source of DNA damage, replication stress and genome instability. Cells have evolved different strategies to prevent R-loop accumulation. One mechanism relies on the deployment of DNA/RNA helicases for R-loop resolution. Recent studies have revealed that depletion of these specialized DNA/RNA helicases results in the accumulation of DNA/RNA hybrids and R-loops in cell. However, major knowledge gaps remain regarding how these helicases recognize and dissociate R-loops to avoid chromosome damage and how their function is regulated.Chemistry and Biochemistr