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Guidance, Navigation and Control 2024年第1期4卷 86-101页

作者： Bin Zhou kang-kang Zhang Center for Control Theory and Guidance Technology Harbin Institute of Technology Harbin 150001 P.R.China Department of Mechanical Engineering University of Hong Kong Hong KongP.R.China

This paper studies the control of chained nonholonomic systems by using smooth time-varying ***,by using a time-varying state transformation,the chained nonholonomic system is transformed into a linear time-varying ***,with the aid of some properties of a class of parametric Lyapunov equations and time-varying systems theory,smooth time-varying state feedback controller is developed to ensure the exponential convergence of both the system states and *** from existing results,the design parameters in the proposed control strategy are independent of the initial conditions of the ***,as an application of the proposed smooth time-varying feedback,the attitude control problem for underactuated axisymmetric spacecraft is ***,a numerical simulation is presented to validate the effectiveness of the proposed method.

关键词： Nonholonomic systems underactuated spacecraft attitude control smooth time-varying feedback parametric Lyapunov equations

Polyoxometalates for continuous power generation by atmospheric humidity

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Nano Research 2024年第3期17卷 1875-1885页

作者： Tuo Ji Weilin Chen Zhenhui kang Liming Zhang Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Northeast Normal UniversityChangchun 130024China Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&Devices DepartmentSoochow UniversitySuzhou 215123China Macao Institute of Materials Science and Engineering Macao University of Science and TechnologyTaipaMacao 999078China Institute of Functional State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

Atmospheric humidity is a sustainable low-value energy widely existing in natural environment,which is a promising candidate to solve the noncontinuous and low efficiency of low-value energy power *** the mono-substituted Dawson-type polyoxometalates are constructed to be highly dispersed organic ammonium-polyoxoanion clusters and are assembled into thin films power generators with micropores,working in atmospheric *** optimal polyoxometalates generator with the thickness of 7.2μm and the area of 0.36 cm^(2) produces a voltage of 0.68 V and a current density of 19.5μA·cm^(-2) under simulated natural environment,and works continuously and stably under almost all-natural environments(humidity 10%–90%).The highly dispersed polyoxometalate nanoclusters can form microporous in polyoxometalate films to effectively absorb atmospheric humidity and spontaneously form distribution gradient of water,which is the structural basis of power *** continuous power generation may be maintained by the effective adsorption and utilization of H_(2)O,the huge electrostatic field of organic ammonium-polyoxoanion clusters,and the reasonably designed polyoxometalates containing inorganic small ions with high *** is the first humidity generator designed with polyoxometalates,which may provide a new research direction for polyoxometalates in sustainable utilization of low-value energy.

关键词： atmospheric humidity continuous power generations nanomaterials polyoxoanions polyoxometalates

MicroR-9c-5p and novel-mir50 co-target Akt to regulate Lasioderma serricorne reproduction

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Insect Science 2024年第1期31卷 106-118页

作者： Yi Yan Dong-Dong Qin Hong Yang kang-kang Xu Can Li Wen-Jia Yang Provincial Key Laboratory for Agricultural Pest Management of Mountainous Region Institute of EntomologyGuizhou UniversityGuiyangChina Guizhou Provincial Key Laboratory for Rare Animal and Economic Insect of the Mountainous Region College of Biology and Environmental EngineeringGuiyang UniversityGuiyangChina

High fecundity is a common characteristic of insect pests which increases the difficulty of population ***/threonine kinase Akt is an indispensable component of the insulin signaling *** of LsAkt severely hinders reproduction in Lasioderma serricorne,a stored product insect ***,the post-transcriptional pathway of LsAkt in *** remains *** study identified 2 binding sites of miR-9c-5p and novel-mir50 in the coding sequences of *** expression profiles of 2 microRNAs(miRNAs)and LsAkt displayed an opposite pattern during the adult *** reporter assay showed that novel-mir50 and miR-9c-5p could downregulate the expression of *** of miR-9c-5p and novel-mir50 by injection of mimics inhibited the expression of LsAkt and reduced oviposition,decreased egg hatchability,and blocked ovarian *** also decreased the expression of genes involved in ovarian development(LsVg and LsVgR)and the nutritional signaling pathway(LsTOR,LsS6K,and Ls4EBP),and reduced the phosphorylation of ***,injection of miR-9c-5p and novel-mir50 inhibitors induced the expressions of LsAkt,LsVg,LsVgR,LsTOR,LsS6K,and Ls4EBP,enhanced Akt phosphorylation level,and accelerated ovarian *** of bovine insulin downregulated the expression of miR-9c-5p and novel-mir50 and upregulated the LsAkt *** also rescued the reproductive development defects associated with miR-9c-5p/novel-mir50 overexpression,forming a positive regulatory loop of insulin *** results indicate that miR-9c-5p/novel-mir50 regulates the female reproduction of *** by targeting Akt in response to insulin *** data also demonstrate the effects of the insulin/miRNA/Akt regulatory axis in insect reproduction.

关键词： Akt insulin Lasioderma serricorne microRNA reproduction

Occurrence of microplastics in natural and farmland soil in the Qilian Mountains of the Northern Tibetan Plateau

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Journal of Mountain Science 2024年第7期21卷 2159-2172页

作者： kang Qiangqiang ZHANG Yulan kang Shichang ZHANG Shengyin LUO Xi LI Longrui WANG Zhaoqing ZHANG Shuncun Key Laboratory of Petroleum Resources Exploration and Evaluation Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Cryospheric Science and Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of Earth and Environmental Sciences Lanzhou UniversityLanzhou 730000China

Microplastics(MPs)become ubiquitous in soil and are an environmental and public health concern ***,the status of MPs in natural and farmland soils in remote areas remains poorly *** this study,we investigated the characteristics of MPs in natural and farmland soils along two transects in the Qilian Mountains of the northern Tibetan *** average abundance of MPs in natural and farmland soils was 29,778 and 56,123 items kg^(-1),respectively,with a detection size range of 10-1000μ*** in the size range of 10-100μm accounted for 84.1%of particles *** the 21 polymers detected,polyethylene dominated in both farmland and natural *** shape of MPs was dominated by fragments(95.8%),followed by fibers(3.8%)and beads(0.4%).The abundance of MPs was positively correlated with increasing altitude in natural *** was no significant correlation between the abundance of MPs and soil physicochemical properties due to the narrow range of values of soil physicochemical *** the growing concern regarding MPs pollution,research on the status of MPs in high altitude and remote areas is critical to understanding their global cycle.

关键词： Microplastics pollution Soil Remote areas Tibetan Plateau

Research on blade tip clearance cavitation and turbulent kinetic energy characteristics of axial flow pump based on the partially-averaged Navier-Stokes model

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Journal of Hydrodynamics 2024年第1期36卷 184-201页

作者： Xiao-qi Jia Shuai-kang Zhang Zu-chao Zhu Key Laboratory of Fluid Transmission Technology of Zhejiang Province Zhejiang Sci-Tech UniversityHangzhou310018China

To reveal the cavitation forms of tip leakage vortex(TLV)of the axial flow pump and the flow mechanism of the flow field,this research adopts the partially-averaged Navier-Stokes(PANS)model to simulate the cavitation values of an axial flow pump,followed by experimental *** experimental result shows that compared with the shear stress transport(SST)k-ωmodel,the PANS model significantly reduces the eddy viscosity of the flow field to make the vortex structure clearer and allow the turbulence scale to be more robustly *** cavitation area within the axial flow pump mainly comprises of TLV cavitation,clearance cavitation and tip leakage flows combined effect of triangular cloud cavitation *** formation and development of cavitation are accompanied by the formation and evolution of vortex,and variations in vortex structure also generate and promote the development of *** addition,an in-depth analysis of the relationship between the turbulent kinetic energy(TKE)transport equation and cavitation patterns was also conducted,finding that the regions with relatively high TKE are mainly distributed around gas/liquid boundaries with serious cavitation and evident gas-liquid *** phenomenon is mainly attributed to the combined effect of the pressure action term,stress diffusion term and TKE production term.

关键词： Cavitation axial flow pump tip leakage vortex(TLV) partially-averaged Navier-Stokes(PANS)model turbulent kinetic energy(TKE)

THE SCHUR TEST OF COMPACT OPERATORS

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Acta Mathematica Scientia 2024年第5期44卷 2041-2050页

作者： Qijian kang Maofa WANG School of Mathematics and Statistics Lingnan Normal UniversityZhanjiang524048China School of Mathematics and Statistics Wuhan UniversityWuhan430072China

Infinite matrix theory is an important branch of function *** linear operator on a complex separable infinite dimensional Hilbert space corresponds to an infinite matrix with respect a orthonormal base of the space,but not every infinite matrix corresponds to an *** classical Schur test provides an elegant and useful criterion for the boundedness of linear operators,which is considered a respectable mathematical *** this paper,we prove the compact version of the Schur ***,we provide the Schur test for the Schatten class S_(2).It is worth noting that our main results can be applicable to the general matrix without limitation on non-negative *** finally provide the Schur test for compact operators from l_(p) into l_(q).

关键词： Schur test compact operator infinite matrix

A review on the multi-scaled structures and mechanical/thermal properties of tool steels fabricated by laser powder bed fusion additive manufacturing

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1048-1071页

作者： Huajing Zong Nan kang Zehao Qin Mohamed El Mansori Arts et Metiers Institute of Technology MSMPHESAM UniversitéChâlons-en-Champagne F-51006France Texas A&M Engineering Experiment Station Institute for Manufacturing SystemsCollege Station TX77843USA

The laser powder bed fusion(LPBF) process can integrally form geometrically complex and high-performance metallic parts that have attracted much interest,especially in the molds *** appearance of the LPBF makes it possible to design and produce complex conformal cooling channel systems in ***,LPBF-processed tool steels have attracted more and more *** complex thermal history in the LPBF process makes the microstructural characteristics and properties different from those of conventional manufactured tool *** paper provides an overview of LPBF-processed tool steels by describing the physical phenomena,the microstructural characteristics,and the mechanical/thermal properties,including tensile properties,wear resistance,and thermal *** microstructural characteristics are presented through a multiscale perspective,ranging from densification,meso-structure,microstructure,substructure in grains,to ***,a summary of tool steels and their challenges and outlooks are introduced.

关键词： additive manufacturing laser powder bed fusion tool steel multi-scaled structure mechanical properties thermal properties

Bilateral adrenal histoplasmosis in a Malaysian tertiary hospital:Report of four cases

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Asian Pacific Journal of Tropical Medicine 2024年第2期17卷 91-94页

作者： kang WH Norasyikin Abdul Wahab Department of Medicine Faculty of Medicine and Health SciencesUniversity Tunku Abdul RahmanMalaysia Department of Medicine Pusat Perubatan Universiti KebangsaanMalaysia

Rationale:Adrenal histoplasmosis can present as bilateral adrenal enlargement with constitutional symptoms and/or adrenal *** these patients are initially investigated as secondary adrenal metastases before eventually their diagnosis established by histopathological examination of the adrenal *** concerns:We report 4 cases of patients aged 55-78 who presented with hypocortisolism and bilateral adrenal ***:Bilateral adrenal ***:Three patients received antifungal treatment for at least one year while 1 patient passed away before the initiation of antifungal ***:Two patients’adrenal function recovered not requiring any steroid replacement,while 1 patient still requires long-term steroid ***:Adrenal histoplasmosis should be excluded in patients from endemic areas presenting with bilateral adrenal masses and adrenal *** patients have an exposure to bird droppings,bat guano or soil contaminated with histoplasmosis *** examination of biopsied adrenal tissues is still the gold standard investigation as serology and molecular diagnostic methods are still not widely available in most centers in Malaysia.

关键词： Adrenal histoplasmosis Histoplasmosis Bilateral adrenal masses

Intelligent reflecting surfaces-assisted millimeter wave communication:Channel estimation based on deep learning

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The Journal of China Universities of Posts and Telecommunications 2024年第1期31卷 49-56页

作者： kang Xiaofei Wang Tian Liang Xian College of Communication and Information Engineering Xi'an University of Science and TechnologyXi'an 710600China

In response to the challenge posed by the complexity of the system and the difficulty in obtaining accurate channel state information(CSI)for millimeter wave communication assisted by intelligent reflecting surfaces(IRS),we propose a deep learning-based channel estimation *** proposed scheme employs a hybrid active/passive IRS architecture,wherein the least square(LS)algorithm is initially utilized to acquire the channel estimate from the active ***,this estimation is interpolated to obtain a preliminary channel estimation and ultimately refined into an accurate estimate of the channel using the channel super-resolution convolutional neural network(Chan-SRCNN)deep learning *** simulation results demonstrate that the proposed scheme surpasses LS,orthogonal matching pursuit(OMP),synchronous OMP(SOMP),and deep neural network(DNN)channel estimation algorithms in terms of normalized mean squared error(NMSE)performance,thereby validating the feasibility of the proposed approach.

关键词： intelligent reflecting surface millimeter wave channel estimation deep learning

Effect of acacetin on inhibition of apoptosis in Helicobacter pyloriinfected gastric epithelial cell line

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3624-3634页

作者： Qi-Xi Yao Zi-Yu Li Hou-Le kang Xin He Min kang Department of Gastroenterology The Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina Department of Orthopaedics The Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina Department of Emergency Luzhou People’s HospitalLuzhou 646000Sichuan ProvinceChina

BACKGROUND Helicobacter pylori(***)infection can cause extensive apoptosis of gastric epithelial cells,serving as a critical catalyst in the progression from chronic gastritis,gastrointestinal metaplasia,and atypical gastric hyperplasia to gastric *** eradication of *** is paramount for ameliorating the pathophysiological conditions associated with chronic inflammation of the gastric mucosa and the primary prevention of gastric ***,which has multifaceted pharmacological activities such as anti-cancer,anti-inflammatory,and antioxidative properties,has been extensively investigated across various ***,the impact and underlying mechanisms of action of acacetin on ***-infected gastric mucosal epithelial cells remain *** To explore the defensive effects of acacetin on apoptosis in ***-infected GES-1 cells and to investigate the underlying *** GES-1 cells were treated with *** and acacetin in *** viability was assessed using the CCK-8 assay,cell mortality rate via lactate dehydrogenase assay,alterations in cell migration and healing capacities through the wound healing assay,rates of apoptosis via flow cytometry and TUNEL staining,and expression levels of apoptosis-associated proteins through western blot *** *** infection led to decreased GES-1 cell viability,increased cell mortality,suppressed cell migration,increased rate of apoptosis,increased expressions of Bax and cle-caspase3,and decreased Bcl-2 ***,acacetin treatment enhanced cell viability,mitigated apoptosis induced by *** infection,and modulated the expression of apoptosis-regulatory proteins by upregulating Bcl-2 and downregulating Bax and cleaved *** Acacetin significantly improved GES-1 cell viability and inhibited apoptosis in ***-infected GES-1 cells,thereby exerting a protective effect on gastric mucosal epithelial cells.

关键词： Gastric epithelial GES-1 cells Helicobacter pylori Infection Acacetin Antibiotic resistance Apoptosis