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AbstractThe present work examines the analytical solutions of the mathematical fractional Maxwell fluid model near an infinitely vertical plate. The phenomenon has been expressed in terms of partial differential equations, then transformed the governing equations in non-dimensional form. For the sake of better rheology of rate type fluid, developed a fractional model by applying the new definition of Constant Proportional Caputo (CPC) fractional derivative operator that describe the generalized memory effects. For seeking exact solutions in terms of Mittag-Leffler functions for velocity and temperature, Laplace integral transformation technique is applied. For physical significance of various system parameters on fluid velocity and temperature distributions are demonstrated through various graphs by using graphical software. Furthermore, for being validated the acquired solutions, some limiting models such as ordinary Newtonian model had been recovered from fractional model. It is also analyzed that for Newtonian heating and non-uniform velocity conditions, the CPC fractional operator is the finest fractional model to describe the memory effect of velocity and energy distribution. Moreover, the graphical representations of the analytical solutions illustrated the main results of the present work. Also, in the literature, it is observed that to derived analytical results from fractional fluid models developed by the various fractional operators, is difficult and this article contributing to answer the open problem of obtaining analytical solutions the fractionalized fluid models.

The assessment of ecotourism suitability is crucial for sustainable regional development and is seen as an effective strategy to achieve both environmental protection and economic growth. One of the key challenges in land research is effectively identifying potential ecotourism resources while balancing regional protection and development. This study mapped the suitability of ecotourism in Zhangjiajie, China, using a combination of various geospatial data sources and four machine-learning techniques. Additionally, an indicator system was developed, covering the ecological environment, geological geomorphology, socioeconomics, and resource availability. The prediction results for suitability classified the area into four categories: highly suitable, moderately suitable, marginally suitable, and unsuitable; based on the ensemble results generated by the four algorithms, these categories accounted for 19.34%, 28.78%, 23.87%, and 28.01% of the total area, respectively. This study’s findings illustrate the spatial distribution of ecotourism suitability in Zhangjiajie, providing valuable insights for identifying potential ecotourism resources as well as informing regional planning and policy-making.

Dairy cows receiving a prolonged high-concentrate diet express an elevated concentration of lipopolysaccharides (LPSs) in the peripheral blood circulation, accompanied by a series of systemic inflammatory responses; however, the specific impacts of inflammation are yet to be determined. Cecropin-like antimicrobial peptides have become a research hotspot regarding antimicrobial peptides because of their excellent anti-inflammatory activities, and cecropin A is a major member of the cecropin family. To elucidate the mechanism of cecropin A as anti-inflammatory under the condition of sub-acute ruminal acidosis (SARA) in dairy cows, we induced inflammation in bEECs with LPS (10 µg/mL) and then added cecropin A (25 µM). Afterwards, we detected three categories of indexes including oxidative stress indices, inflammation-related genes, and apoptosis-related genes in bovine endometrial epithelial cells (bEECs). The results indicated that cecropin A has the ability to reduce inflammatory factors TNF-α, IL-1β, and IL-8 and inhibit the MAPK pathway to alleviate inflammation. In addition, cecropin A is able to reduce reactive oxygen species (ROS) levels and alleviates LPS-induced oxidative stress and mitochondrial dysfunction by downregulating NADPH Oxidase (NOX), and upregulating catalase (CAT), glutathione peroxidase (GPX), and superoxide dismutase (SOD). Furthermore, cecropin A demonstrates the ability to inhibit apoptosis by suppressing the mitochondrial-dependent apoptotic pathway, specifically Fas/FasL-caspase-8/-3. The observed increase in the Bcl-2/Bax ratio, a known apoptosis regulator, further supports this finding. In conclusion, our study presents novel solutions for addressing inflammatory responses associated with SARA.

Based on social exchange theory and attribution theory, this paper explores the role of affective commitment and organizational support in the relationship between career growth and the engagement of knowledge workers. The results show that (1) career growth has a positive impact on knowledge workers’ organizational engagement; (2) career goal progress and professional ability development promote job engagement; (3) career growth has a positive effect on affective commitment, which in turn influences employee engagement; (4) affective commitment plays a mediating role in the effect of career growth on engagement; and (5) perceived organizational support positively moderates the relationship between career growth and affective commitment.

Abstract Background Coffee silverskin is a thin film that covers the raw coffee bean. In general, coffee silverskin, which detaches during the coffee roasting process, is disposed as firelighters or dispatched to landfills and can cause serious environmental pollution. The aim of this study was to investigate the feasibility of using coffee silverskin as a functional material in cosmetics by evaluating its bioactive ingredients, antioxidative activity, cytoprotective effect, matrix metalloproteinase-1 (MMP-1)-inhibiting effect, and anti-melanogenesis effect. Results To this end, a 50% ethanol (EtOH) extract and its ethyl acetate (EtOAc) fraction were prepared from coffee silverskin; caffeine was found to be the major compound in the extract. Both the 50% EtOH extract and its EtOAc fraction exhibited antioxidant activities. However, the EtOAc fraction showed a greater radical-scavenging activity and reducing power than that shown by the 50% EtOH extract. Furthermore, the EtOAc fraction increased cell viability in a UVB-irradiated human keratinocyte injury model and significantly suppressed UVB-induced MMP-1 expression and α-melanocyte-stimulating hormone (α-MSH)-stimulated melanin production in HaCaT keratinocytes and B16F1 melanocytes, respectively. Interestingly, caffeine, the major component of the EtOAc fraction, did not show an inhibitory effect. Thus, the antioxidant capacity of the coffee silverskin extract may be attributable to some compounds that exhibit a high antioxidant capacity even at low concentrations or the total antioxidant capacity of various constituent phenolic compounds. Conclusion Our findings indicate that coffee silverskin has the potential for application as a natural functional material in multifunctional cosmetics.

Central nervous system tumors have resisted effective chemotherapy because most therapeutics do not penetrate the blood-tumor-brain-barrier. Nanomedicines between  ~ 10 and 100 nm accumulate in many solid tumors by the enhanced permeability and retention effect, but it is controversial whether the effect can be exploited for treatment of brain tumors. PLX038A is a long-acting prodrug of the topoisomerase 1 inhibitor SN-38. It is composed of a 15 nm 4-arm 40 kDa PEG tethered to four SN-38 moieties by linkers that slowly cleave to release the SN-38. The prodrug was remarkably effective at suppressing growth of intracranial breast cancer and glioblastoma (GBM), significantly increasing the life span of mice harboring them. We addressed the important issue of whether the prodrug releases SN-38 systemically and then penetrates the brain to exert anti-tumor effects, or whether it directly penetrates the blood-tumor-brain-barrier and releases the SN-38 cargo within the tumor. We argue that the amount of SN-38 formed systemically is insufficient to inhibit the tumors, and show by PET imaging that a close surrogate of the 40 kDa PEG carrier in PLX038A accumulates and is retained in the GBM. We conclude that the prodrug penetrates the blood-tumor-brain-barrier, accumulates in the tumor microenvironment and releases its SN-38 cargo from within. Based on our results, we pose the provocative question as to whether the 40 kDa nanomolecule PEG carrier might serve as a Trojan horse to carry other drugs past the blood-tumor-brain-barrier and release them into brain tumors.

There inevitably existed multi-correlated failure modes in the mechanism motion process,and these modes are expressed as functions of random variables.Firstly,a reliability calculation model for the mechanism motion under multi-failure mode is built and solved.Secondly,taking the rotating guide-bar mechanism as example,the calculation solution of the motion accuracy reliability under multi-correlated failure mode is carried out based on the method of Monte Carlo.Lastly,the guide-bar mechanism reliability curves under different times are got,and the theory foundation for mechanism dynamic optimum design is provided.This method with high accuracy,has some theory meaning and application value.

The solid models of the logarithmic spiral cam mechanism and common cam mechanism are established by using SolidWorks,and the kinematics simulation is carried out.Then,by using the software of ANSYS / LS-DYNA,the dynamics analysis of the two kinds of cam mechanism is carried out,and the variation situation of the maximum stress of cam mechanism and the follower changing with time is obtained.By contrast analysis between the dynamics simulation and the kinematical simulation of logarithmic spiral cam mechanism and common cam mechanism,find that the logarithmic spiral cam mechanism drive is more steady during the operation,and the force variation and the average stress of cam and follower are lower,which indicates that the logarithmic spiral cam mechanism is superior to common cam mechanism,and possessed of popularization and application value.

Macrophages and dendritic cells are recognized as key players in the defense against mycobacterial infection. Recent research has confirmed that alveolar epithelial cells (AECs) also play important roles against mycobacterium infections. Thus, establishing a stable cattle AEC line for future endogenous immune research on bacterial invasion is necessary. In the present study, we first purified and immortalized type II AECs (AEC II cells) by transfecting them with a plasmid containing the human telomerase reverse trancriptase gene. We then tested whether or not the immortalized cells retained the basic physiological properties of primary AECs by reverse-transcription polymerase chain reaction and Western blot. Finally, we tested the secretion capacity of immortalized AEC II cells upon stimulation by bacterial invasion. The cattle type II alveolar epithelial cell line (HTERT-AEC II) that we established retained lung epithelial cell characteristics: the cells were positive for surfactants A and B, and they secreted tumor necrosis factor-α and interleukin-6 in response to bacterial invasion. Thus, the cell line we established is a potential tool for research on the relationship between AECs and Mycobacterium tuberculosis.