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Detection and Characterization of β-Lactam Resistance in Haemophilus parasuis Strains from Pigs in South China

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Journal of Integrative Agriculture 2012年第1期11卷 116-121页

作者： GUO Li-li ZHANG jian-min XU cheng-gang REN Tao ZHANG Bin chen ji-dang LIAO Ming Key Laboratory of Animal Disease Control and Prevention Ministry of Agriculture/Key Laboratory of Zoonoses Prevention and Control of GuangdongCollege of Veterinary MedicineSouth China Agricultural UniversityGuangzhou 510642P.R.China

To characterize the β-lactam resistance in veterinary clinical isolates of Haemophilus parasuis, 115 isolates were examined for the β-lactam resistance, the possession of β-lactamase, and the presence of β-lactamase genes. The genetic relationship among isolates was evaluated by pulsed-field gel electrophoresis （PFGE）. Overall, the commonly detected resistance phenotypes were resistant to ampicillin （26.09%）, penicillin （22.61%）, amoxicillin （21.74%）, cefazolin （14.78%）, cefaclor （12.17%）, and cefotaxime （6.96%）. These strains showed high minimal inhibitory concentration （MICs） to oxacillin. 20.87% strains produced β-lactamase, and 4.35% strains showed extended-spectrum b-lactamase （ESBL） phenotype. Moreover, 19 strains harboured bla genes including TEM-1 （n=5）, TEM-116 （n=10）, and ROB-1 （n=5）. Significantly, one strain possessed both TEM-1 and ROB-1, and displayed resistance to cefotaxime （MIC=8 mg L-1）. The epidemiological analysis of PFGE revealed high genetic diversity among bla-positive isolates. This work shows that TEM- and ROB-type β-lactamases are prevalent in H. parasuis isolates in China.

关键词： Haemophilus parasuis β-lactamase genes resistance pulsed-field gel electrophoresis

Bias distribution and regulation in photoelectrochemical overall water-splitting cells

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National Science Review 2024年第4期11卷 141-150页

作者： Kun dang Siqin Liu Lei Wu Daojian Tang jing Xue jiaming Wang Hongwei ji Chuncheng chen Yuchao Zhang jincai Zhao Key Laboratory of Photochemistry CAS ResearchEducation Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

The water oxidation half-reaction at anodes is always considered the rate-limiting step of overall water splitting（OWS）,but the actual bias distribution between photoanodes and cathodes of photoelectro chemical（PEC） OWS cells has not been investigated *** this work,we find that,for PEC cells consisting of photoanodes（nickel-modified n-Si [Ni/n-Si] and α-Fe2O3） with low photovoltage(Vph 1V,the bias required for cathode activation can be significantly reduced,exhibiting a kinetics-controlled *** investigations show that the bias distribution can be regulated by tuning the electrolyte pH and using alternative half-reaction ***,a volcano plot is presented for the rational design of the overall reactions and unbiased PEC *** by this,an unbiased PEC cell consisting of a simple Ni/n-Si photoanode and Pt cathode is assembled,delivering a photo current density of 5.3±0.2 mA cm-2.

关键词： photoelectrochemistry overall reaction cell bias distribution photoanode water splitting

Robust fixed-time flight controller for a dual-system convertible UAV in the cruise mode

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Defence Technology（防务技术） 2024年第9期39卷 53-66页

作者： Lulu chen Zhenbao Liu Qingqing dang Wen Zhao Wenyu chen School of Civil Aviation Northwestern Polytechnical UniversityXi'an 710072China Shenzhen Research Institute of Northwestern Polytechnical University Shenzhen 518057China Air and Missile Defense College Air Force Engineering UniversityXi'an 710051China

This paper investigates the attitude tracking control problem for the cruise mode of a dual-system convertible unmanned aerial vehicle(UAV)in the presence of parameter uncertainties,unmodeled uncertainties and wind ***,a fixed-time disturbance observer(FXDO)based on the bi-limit homogeneity theory is designed to estimate the lumped disturbance of the convertible UAV ***,a fixed-time integral sliding mode control(FXISMC)is combined with the FXDO to achieve strong robustness and chattering ***-limit homogeneity theory and Lyapunov theory are applied to provide detailed proof of the fixed-time ***,numerical simulation experimental results verify the robustness of the proposed algorithm to model parameter uncertainties and wind *** addition,the proposed algorithm is deployed in a open-source UAV autopilot and its effectiveness is further demonstrated by hardware-in-the-loop experimental results.

关键词： Convertible UAV Flight control Disturbance observer Fixed-time control

Tailoring of a robust asymmetric aramid nanofibers/MXene aerogel film for enhanced infrared thermal camouflage and Joule heating performances

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Nano Research 2024年第3期17卷 1990-1998页

作者： Wanbin dang Wei Guo Wenting chen Qiuyu Zhang Key Laboratory of Special Functional and Smart Polymer Materials of Ministry of Industry and Information Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China

The development of infrared(IR)surveillance technology has led to a growing interest in thermal ***,the trade-off relationship between low IR-emissivity and thermal insulation hinders the advance of thermal camouflage ***,guided by multi-physics simulation,we show a design of asymmetric aramid nanofibers/MXene(ANF/MXene)aerogel film that realizes high-efficient thermal camouflage *** rationale is that the asymmetric structure contains a thermal-insulation three-dimensional(3D)network part to prevent effective heat transfer and a low IR-emissivity(~0.3)dense surface layer to suppress radiative heat *** is remarkable that the synergy mechanism in the topology structure contributes to over 40%reduction of target radiation ***,the tailored asymmetric ANF/MXene aerogel film also enables sound mechanical properties such as a Young’s modulus of 44.4 MPa and a tensile strength of 1.3 MPa,superior to most aerogel *** also exhibits great Joule heating performances including low driving voltage(4 V),fast thermal response(<10 s),and long-term stability,further enabling its versatile thermal camouflage *** work offers an innovative design concept to configure multifunctional structures for next-generation thermal management applications.

关键词： asymmetric aerogel film low infrared(IR)-emissivity thermal insulation IR thermal camouflage Joule heating performance

Differences in Variations of Long-Lived and Short-Lived Summer Heat Waves during 1981-2020 over Eastern China and Their Corresponding Large-Scale Circulation Anomalies

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Journal of Meteorological Research 2024年第3期38卷 414-436页

作者： Liqun ji Haishan chen Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of EducationNanjing University of Information Science&TechnologyNanjing210044China School of Atmospheric Sciences Nanjing University of Information Science&TechnologyNanjing210044China

Using daily maximum temperature(Tmax)data from 516 observation stations in eastern China from 1981 to 2020,this study employed a relative threshold method to define short-and long-lived heat waves(HWs)by considering regional climate differences to investigate the spatial characteristics and evolution of large-scale circulation during summer *** results demonstrated spatial disparities in the frequency distribution of HWs of different durations and differences in the magnitude of duration and intensity between short-and long-lived *** orthogonal function analysis revealed three dominant spatial modes for both short-and long-lived *** first mode showed that short-lived HWs occur prominently in both northern and southern regions,whereas long-lived HWs mainly occur in the northern *** second mode was characterized by a meridional dipole pattern in both *** third mode exhibited a quadrupole pattern for short-lived HWs and a tripole pattern for long-lived *** in the center locations of anomalies in the 500-hPa geopotential height and 850-hPa wind fields significantly influenced the temperature and precipitation anomaly distribution of typical HWs by affecting the warm column in the lower troposphere,cloud distribution,and moisture ***,the atmospheric circulation evolution processes of typical HWs associated with the different modes of long-and short-lived HWs were linked to distinct teleconnection *** the three modes of long-lived(short-lived)HWs,there was stronger(weaker)wave flux activity with multiple(single)propagation *** westward Atlantic wave train activity at 300 hPa triggered the synergistic action of meridional and zonal wave fluxes,favoring the strengthening and maintenance of positive anomalies in geopotential height of 500 *** may have contributed to the formation of long-lived *** findings provide valuable insights to enhance our understanding and prediction of summer

关键词： short-lived heat waves(HWs) long-lived HWs empirical orthogonal function(EOF)modes large-scale atmospheric circulation

Modeling solubility of oxaprozin and irbesartan in biorelevant complex solutions based on a combination of pH-dependent and micellar solubilization models

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Chinese Journal of Chemical Engineering 2024年第8期72卷 34-43页

作者： chen Shen Yuanhui ji jiangsu Province Hi-Tech Key Laboratory for Biomedical Research School of Chemistry and Chemical EngineeringSoutheast UniversityNanjing 211189China

Biological solubility is one of the important basic parameters in the development process of poorly soluble drugs,but the current measurement methods are mainly based on a large number of experiments,which are time-consuming and *** is still a lack of effective theoretical models to accurately describe and predict the biological solubility of drugs to reduce ***,in this study,osaprazole and irbesartan were selected as model drugs,and their solubility in solutions containing surfactants and biorelevant media was measured *** calculating the parameters of each component using the perturbed-chain statistical associating fluid theory(PC-SAFT)model,combined with pH-dependent and micellar solubilization models,the thermodynamic phase behavior of the two drugs was successfully modeled,and the predicted results were in good agreement with the experimental *** results demonstrate that the model combination used provides important basic parameters and theoretical guidance for the development and screening of poorly soluble drugs and related formulations.

关键词： Biorelevant media pH-dependent solubility Micellar solubilization PC-SAFT Active pharmaceutical ingredients

Nondestructive Nonlinear Optical Microscopy Revealed the Blackening Mechanism of Ancient Chinese Jades

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Research 2024年第3期2023卷 391-399页

作者： Yaxin chen Rong Wang Minbiao ji State Key Laboratory of Surface Physics and Department of Physics Human Phenome InstituteAcademy for Engineering and TechnologyKey Laboratory of Micro and Nano Photonic Structures(Ministry of Education)Yiwu Research Institute of Fudan UniversityFudan UniversityShanghai 200433China Department of Cultural Heritage and Museology Fudan UniversityShanghaiChina

Jade is most valued in Chinese culture since ancient times. For unearthed jade artifacts, the alteration color resulting from weathering effects and human activities provides information for cultural heritage conservation, archaeology, and history. Currently, the noninvasive 3-dimensional characterization of jade artifacts with high chemical and spatial resolution remains challenging. In this work, we applied femtosecond pump–probe microscopy and second harmonic generation microscopy techniques to study the black alteration of an ancient jade artifact of the late Spring and Autumn period (546 to 476 BC). The direct cause of the “mercury alteration” phenomena was discovered to be the conversion of metacinnabar from buried cinnabar in the tomb. Furthermore, a 3-dimensional optical reconstruction of the black alteration was achieved, providing a high-resolution method for analyzing the blackening mechanism without the need of sample damage. Our approach opens up new opportunities to extract microscopic spatiochemical information for a broad range of alteration colors in jade artifacts.

关键词： pump Nonlinear buried

Regulating Anderson localization with structural defect disorder

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Chinese Physics B 2024年第10期33卷 102-107页

作者： Mouyang cheng Haoxiang chen ji chen School of Physics Peking UniversityBeijing 100871China Interdisciplinary Institute of Light-Element Quantum Materials and Research Center for Light-Element Advanced Materials Peking UniversityBeijing 100871China Frontiers Science Center for Nano-Optoelectronics Peking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China

Localization due to disorder has been one of the most intriguing theoretical concepts that evolved in condensed matter ***,we expand the theory of localization by considering two types of disorders at the same time,namely,the original Anderson’s disorder and the structural defect disorder,which has been suggested to be a key component in recently discovered two-dimensional amorphous *** increasing the degree of both disorders could induce localization of wavefunction in real space,we find that a small degree of structural defect disorder can significantly enhance the *** the degree of structural defect disorder increases,localized states quickly appear within the extended phase to enter a broad crossover region with mixed *** establish two-dimensional diagrams for the wavefunction localization and conductivity to highlight the interplay between the two types of *** theoretical model provides a comprehensive understanding of localization in two-dimensional amorphous materials and highlights the promising tunability of their transport properties.

关键词： Anderson localization structural defect disorder electronic transport properties

Evaluating the efficacy of immunotherapy in gastric cancer:Insights from immune checkpoint inhibitors

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World Journal of Gastroenterology 2024年第32期30卷 3726-3729页

作者： Yu-Nuo Yang Li-Sheng Wang Yan-Qi dang Guang ji Institute of Digestive Diseases Longhua HospitalChina-Canada Center of Research for Digestive DiseasesShanghai University of Traditional Chinese MedicineShanghai 200032China Department of Biochemistry University of OttawaOttawa K1H 8M5ONCanada

The emergence of immunotherapy,particularly immune checkpoint inhibitors(ICIs),represents a groundbreaking approach to treating gastric cancer(GC).However,the prognosis of GC patients receiving ICI treatment is influenced by various *** manuscript identified sarcopenia and myosteatosis as independent prognostic factors impacting the outcomes of GC patients treated with ***,this study introduced a visual predictive model to estimate the prognosis of GC *** confirmed by further studies,this observation could provide valuable insights to propel the advancement of personalized clinical medicine and the integration of precision medicine practices.

关键词： Gastric cancer Immune checkpoint inhibitors Sarcopenia Myosteatosis Prediction model