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Prevalence and Resistance Profile of muenchen Cefotaximase (CTX-m) group 1 Extended Spectrum Beta-Lactamase (ESBL)-Producing Uropathogenic Escherichia coli Strains in Dakar, Senegal

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Open Journal of medical microbiology 2023年第2期13卷 137-145页

作者： Abdoulaye Seck Babacar Ndiaye Abdou Diop malick Ndao Cheikh Fall Assane Dieng Thierno Abdoulaye Diallo Chantal mahou Philippe Dubrous Laboratoire de Biologie médicale Institut Pasteurde Dakar Dakar Senegal Laboratoire de Bactériologie-Virologie Université Cheikh Anta Diop Dakar Senegal Laboratoire National de Santé Publique Thies Senegal Laboratoire de Bactériologie-Virologie H&#244pital Aristide Le Dantec Dakar Senegal

Background: Extended-spectrum beta-lactamase (ESBL) producing bacteria are a real public health problem, particularly in Africa. Among these ESBLs, there are the muenchen Cefotaximase (CTX-m) described all over the world of which the most frequent is the CTX-m of group 1 particularly the CTX-m-15 variant. The objective of this study was to determine the prevalence of CTX-m group 1 ESBL-producing Escherichia coli strains and to test their antibiotics susceptibility profile. methodology: A retrospective cross-sectional descriptive study was conducted to detect ESBL-secreting Escherichia coli strains by the synergy test. Identification of CTX-m type ESBL from group 1 was performed using the NG-Test CTX-m rapid diagnostic test (NG-Biotech®). Antibiotic susceptibility profile was determined using CA-SFm/EUCAST guidelines 2019. Data entry and statistical analysis were performed with Excel version 2010 and SPSS 20.0 respectively. Results: Eighty-two ESBL-producing Escherichia coli strains were tested. A group 1 CTX-m ESBL was detected in 75.6% of the strains (n = 62). These strains were highly resistant to cefotaxim (100%), aztreonam (100%), ceftazidim (85.4%) and cefepim (66.1%). They were also resistant to quinolones, gentamycin and sulfadoxine-trimethoprim combination. However, these strains showed sensitivity to ertapenem (100%), cefoxitin (69.3%), tigecyclin (66%), and amikacin (66.1%). The combination of piperacillin and tazobactam was active on 30.6% of the strains against 6.4% for the combination of amoxicillin and clavulanic acid. Conclusion: The CTX-m type ESBL of group 1 was present in the majority of ESBL-producing Escherichia colis trains. Despite the production of this enzyme conferring resistance to most beta-lactam antibiotics, some antibiotics remain active to treat infections caused by these germs.

关键词： Escherichia coli ESBL CTX-m group Prevalence Antibiotic Resistance

metal-modulated epitaxy of mg-doped Al_(0.80)In_(0.20)N-based layer for application as the electron blocking layer in deep ultraviolet light-emitting diodes

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Journal of Semiconductors 2024年第5期45卷 80-89页

作者： Horacio Irán Solís-Cisneros Carlos Alberto Hernández-Gutiérrez Enrique Campos-González máximo López-López Optomechatronics group Tecnológico Nacional de México Campus Tuxtla Gutiérrezcarretera Panamericana 1080C.P.29050Tuxtla GutiérrezChiapasMéxico Departamento de Física Instituto Nacional de Investigaciones NuclearesCarretera México-Toluca s/nC.P.52750La Marquesa OcoyoacacMéxico Departamento de Física Centro de Investigación y estudios Avanzados del Instituto Politécnico NacionalAv.Instituto Politécnico Nacional 2508San Pedro ZacatencoGustavo A.Madero07360 Ciudad de MéxicoCDMXMéxico

This work reports the growth and characterization of p-AlInN layers doped with mg by plasma-assisted molecular beam epitaxy(PAmBE).AlInN was grown with an Al molar fraction of 0.80 by metal-modulated epitaxy(mmE)with a thickness of 180 nm on Si(111)substrates using AlN as buffer *** substrate temperatures were used to enhance the incorporation of indium atoms into the alloy without clustering,as confirmed by X-ray diffraction(XRD).Cathodoluminescence measurements revealed ultraviolet(UV)range ***,Hall effect measurements indicated a maximum hole mobility of 146 cm^(2)/(V∙s),corresponding to a free hole concentration of 1.23×10^(19)cm^(−3).The samples were analyzed by X-ray photoelectron spectroscopy(XPS)estimating the alloy composition and extracting the Fermi level by valence band ***-doped AlInN layers were studied for use as the electron-blocking layer(EBL)in LED *** varied the Al composition in the EBL from 0.84 to 0.96 molar fraction to assess its theoretical effects on electroluminescence,carrier concentration,and electric field,using SILVACO *** results from this study highlight the importance and capability of producing high-quality mg-doped p-AlInN layers through *** simulations suggest that an Al content of 0.86 is optimal for achieving desired outcomes in electroluminescence,carrier concentration,and electric field.

关键词： metal-modulated epitaxy AlInN DUV-LED EBL simulation

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Study on tungsten sintering temperature field based on electromagnetic simulation and computational fluid dynamics

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Tungsten 2024年第2期6卷 355-366页

作者： Lu-Yan Wang Yue-Guang Yu Jian-Xin Dong Kai-Ping Du Shan-Yu Liu Cao-Bing Li University of Science and Technology Beijing Beijing 100083China BGRImm Technology group Beijing 100160China China Iron&Steel Research Institute group Beijing 100081China

In order to study the influence of various sintering variables more intuitively and clearly,electromagnetic field analysis and computational fl uid dynamics are used to analyze the infl uence of gas flow,heating power and other process parameters on the temperature range of medium-frequency sintering in this *** results indicate that the uniformity of temperature fi eld is determined by the gas flow rate and heating *** the heating power is 50 kW,the stable temperature drops about 10 K for every 1 m^(3)·h^(−1)increase of hydrogen *** peak value of the maximum temperature diff erence on the tungsten rods gradually increases with the increase of the hydrogen flow rate,and it appears slightly *** temperature distribution of tungsten rods in furnace is similar with diff erent hydrogen flow *** the same time,the closer to the furnace wall,the higher the temperature of the tungsten *** temperature diff erence between tungsten rods mainly occurred within 1 h after the beginning of *** the heating power can improve the stable temperature,but has little eff ect on the heating *** heating power can increase the peak value of the maximum temperature diff erence on the tungsten rods,but has little eff ect on the occurrence time of the peak value of the maximum temperature diff erence on the tungsten *** the heating power will increase the temperature diff erence of a single tungsten rod,but the temperature diff erence of a single tungsten rod never exceeds 65 *** study can be used to guide the process optimization *** with numerical simulation calculation,the sintering parameters with low energy consumption and high temperature uniformity can be quickly and eff ectively found,thus improving the microstructure and properties of sintered tungsten products.

关键词： Tungsten products Sintering Hydrogen flow rate Heating power

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Factors associated with decreased compliance after on-site extracorporeal membrane oxygenation cannulation for acute respiratory distress syndrome:A retrospective,observational cohort study

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Journal of Intensive medicine 2024年第2期4卷 194-201页

作者： Sylvain Le Pape Florent Joly François Arrivé Jean-Pierre Frat maeva Rodriguez maïa Joos Laura marchasson mathilde Wairy Arnaud WThille Rémi Coudroy Centre Hospitalier Universitaire de Poitiers Service de Médecine Intensive RéanimationPoitiersFrance INSERm Centre d'Investigation Clinique 1402 IS-ALIVE Research GroupUniversitéde PoitiersPoitiersFrance

Background Extracorporeal membrane oxygenation(ECmO)for acute respiratory distress syndrome(ARDS)is systematically associated with decreased respiratory system compliance(CRS).It remains unclear whether transportation to the referral ECmO center,changes in ventilatory mode or settings to achieve ultra-protective ventilation,or the natural evolution of ARDS drives this change in respiratory ***,we assessed the precise moment when CRS decreases after ECmO cannulation and identified factors associated with decreased *** To rule out the effect of transportation and the different modes of ventilation on CRS,we conducted a retrospective,single-center,observational cohort study from January 2013 to may 2020,on 22 patients with severe ARDS requiring on-site ECmO and ventilated in pressure-controlled mode to achieve ultra-protective *** was assessed at different time points ranging from 12 h before ECmO cannulation to 72 h after ECmO *** primary outcome was the relative change in CRS between 3 h before and 3 h after ECmO *** secondary outcomes included variables associated with the relative changes in CRS within the first 3 h after ECmO cannulation and the relative changes in CRS at each time *** CRS decreased within the first 3 h after ECmO cannulation(−28.3%,95%confidence interval[CI]:−38.8 to−17.9,Pmild before and after these first 3 h after ECmO *** achieve ultra-protective ventilation,respiratory rate decreased in the mean by–13 breaths/min(95%CI:−15 to−11)and driving pressure by−8.3 cmH2O(95%CI:−11.2 to−5.3),resulting in decreased tidal volume by−3.3 mL/kg of predicted body weight(95%CI:−3.9 to−2.6)as compared to before ECmO cannulation(Pme reduction were significantly associated with decreased CRS after ECmO cannulation,whereas neither respiratory rate,positive end-expiratory pr

关键词： Acute respiratory distress syndrome Extracorporeal membrane oxygenation Driving pressure Respiratory compliance

Expanding the Boundaries of the Chemical Space of DNA methyltransferase 1 modulators

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Computational molecular Bioscience 2024年第1期14卷 1-16页

作者： massyel S. martínez-Cortés Diana L. Prado-Romero José L. medina-Franco DIFACQUIm Research group Department of Pharmacy School of Chemistry Universidad Nacional Autónoma de México Avenida Universidad 3000 Mexico City México

DNA methyltransferase 1 (DNmT1), one of the main epigenetic targets, is involved in the duplication of the DNA methylation pattern during replication, and it is essential for proper mammalian development. Small molecule DNmT1 modulators are attractive for biochemical epigenetic studies and have the potential to become drugs. So far, more than five hundred small molecules have been reported as DNmT1 inhibitors. However, only a limited number of DNmT1 activators have been disclosed because, at least in part, DNmT1 activators are typically regarded as negative data in virtual screening campaigns or optimization projects. This manuscript aims to report the chemical structures and biological activity of small molecules that increase the enzymatic activity of DNmT1. Results of the biochemical experimental assays are discussed. It was found that small molecule activators have a large variety of chemical scaffolds but share pharmacophore features. Visual analysis of the chemical space and multiverse based on molecular fingertips supported that activators are structurally diverse. This is the first report of eight small molecules that increase the enzymatic activity of DNmT1 by more than 400% in an enzymatic-based assay. The outcome warrants further investigation of the epigenetic activity of the compounds in a counter-screen assay, e.g., cell-based and in vivo context.

关键词： Chemical multiverse Chemoinformatics Epigenetics Pharmacophore Hypothesis Small molecules

Incense smoke(IS)inhalation exposure system:Physicochemical characterization,IS particle deposition and clearance in human airway using mPPD model

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Particuology 2024年第4期87卷 271-285页

作者： Vyas Kumar Hafsa Hashmi Anshita Nasreen Ghazi Ansari Jyotsna Singh Inhalation Toxicology Facility Regulatory Toxicology GroupCSR-Indian Institute of Toxicology ResearchLucknow22001UPIndi Academy of Scientific and Innovative Research(AcsSIR) Ghaziabad201002UPIndia Analytical Chemistry Regulatory Toxicology GroupCSIR-Indian Institute of Toxicology ResearchLucknow226001UPIndia

Incense smoke(IS)is source of indoor air pollution and key risk for diverse human *** in-formation is available regarding controlled IS rodent inhalation exposure system and IS particulate matter(Pm)deposition in human *** aimed to demonstrate stable ISPm physicochemical parameters of 10 incense products inside the customized whole body inhalation exposure chamber(without animal)connected to smoke generation unit via aerosol mixing *** analyzed for size segregated Pm emission,ISPm in vitro aerodynamics(mmAD and GSD determination),fine and ultrafine particle's SEm,SEm-EDX and PAH *** real life exposure scenario by utilizing mmAD,GSD and Pm concentration after Tier 1 exposure assessment as key input parameters,ISPm dosimetry in infant(3 months)and adult(21 years male and female)human airways was calculated using multiple-path particle dosimetry(mPPD 3.04)*** median aerodynamic diameter(mmAD)and geo-metric standard deviation(GSD)ranged between 0.55 and 2.10μm and 1.22 to 1.77(polydisperse)***1.0 and Pm0.1 showed multiple morphology and presence of heavy and trace *** like acenaphthylene,anthracene,fluorene,naphthalene and phenanthrene were detected(0.84-143.17μg/g).mPPD results showed higher ISPm deposition in pulmonary region and lowest in trachea bronchial *** deposition in tissue was higher in lower,peripheral lung as compared to upper and central lung *** body inhalation exposure system showed stable IS atmosphere(physi-cochemical parameters)indicating the device suitability in future inhalation *** ISPm deposition fraction and clearance data showed deep lung penetrating and retention behavior with higher risk in infant followed by female and then *** modeled particle deposition and clearance data may be useful in risk assessment analysis of IS.

关键词： Inhalation Incense smoke multiple-path particle dosimetry(mPPD) Particle deposition Particulate matter(Pm) mass median aerodynamic diameter (mmAD) Human airway

mycorrhizal fungi mitigate nitrogen losses of an experimental grassland by facilitating plant uptake and soil microbial immobilization

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Pedosphere 2024年第2期34卷 399-410页

作者： Yangyang JIA marcel G.A.VAN DER HEIJDEN Alain Y.VALZANO-HELD markus JOCHER Florian WALDER Postdoctoral mobile Station of Ecology College of Ecology and EnvironmentXinjiang UniversityÜrümqi 830046China Research group Plant-Soil Interactions AgroscopeZürich 8046Switzerland Research group Climate and Agriculture AgroscopeZürich 8046Switzerland Department of Plant and microbial Biology University of ZürichZürich 8008Switzerland Research group Soil Quality and Soil Use AgroscopeZürich 8046Switzerland

Nitrogen(N)is one of the most limited nutrients of terrestrial ecosystems,whose losses are prevented in tightly coupled cycles in finely tuned *** change-induced N enrichment through atmospheric deposition and application of vast amounts of fertilizer are now challenging the terrestrial N *** mycorrhizal fungi(AmF)are known drivers of plant-soil nutrient fluxes,but a comprehensive assessment of AmF involvement in N cycling under global change is still ***,we simulated N enrichment by fertilization(low/high)in experimental grassland microcosms under greenhouse conditions in the presence or absence of AmF and continuously monitored different N pathways over nine *** found that high N enrichment by fertilization decreased the relative abundance of legumes and the plant species dominating the plant community changed from grasses to forbs in the presence of AmF,based on aboveground *** presence of AmF always maintained plant N:phosphorus(P)ratios between 14 and 16,no matter how the soil N availability *** in plant N:P ratios due to the increased plant N and P uptake might thus be a primary pathway of AmF altering plant community ***,we constructed a comprehensive picture of AmF’s role in N cycling,highlighting that AmF reduced N losses primarily by mitigating N leaching,while N_(2)O emissions played a marginal *** mycorrhizal fungi reduced N_(2)O emissions directly through the promotion of N_(2)O-consuming *** underlying mechanism for reducing N leaching is mainly the AmF-mediated improved nutrient uptake and AmF-associated microbial *** results indicate that synergies between AmF and other soil microorganisms cannot be ignored in N cycling and that the integral role of AmF in N cycling terrestrial ecosystems can buffer the upcoming global changes.

关键词： N cycling N enrichment N uptake N:P ratio plant community structure symbiotic soil fungi

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Optimal Energy Efficiency Based High-speed Flying Control method for Hydraulic Quadruped Robot

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Journal of Bionic Engineering 2024年第3期21卷 1156-1173页

作者： Qingjun Yang Zhenyang Zhang Rui Zhu Dianxin Wang School of mechatronics Engineering Harbin Institute of TechnologyHarbin150000China Nanjing Chenguang group Co.Ltd Nanjing210006China

Herein,a control method based on the optimal energy efficiency of a hydraulic quadruped robot was proposed,which not only realizes the optimal energy efficiency of flying trot gait but also ensures the stability of high-speed ***,the energy consumption per unit distance was adopted as the energy efficiency evaluation index based on the constant pressure oil supply characteristics of the hydraulic system,and the global optimization algorithm was adopted to solve the optimal ***,the gait parameters that affect the energy efficiency of quadruped were analyzed and the mapping relationship between each parameter and energy efficiency was captured,so as to select the optimum combination of energy efficiency parameters,which is significant to improve endurance ***,to ensure the stability of the high-speed flying trot gait motion of the hydraulic quadruped robot,the active compliance control strategy was ***,the proposed method was successfully verified by simulations and *** experimental results reveal that the flying trot gait of the hydraulic quadruped robot can be stably controlled at a speed of 2.2 m/s.

关键词： Hydraulic quadruped robot Flying trot Energy efficiency Active compliance control

Experimental test of a building thermal system for preventive maintenance based on thermoeconomic analysis

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Energy Storage and Saving 2024年第1期3卷 42-51页

作者： I.Prol-Godoy A.Picallo-Perez J.m.Sala-Lizarraga J.Rey-martínez Research group ENEDI Department of Thermal EngineeringUniversity of the Basque Country(UPV/EHU)Bilbao48013Spain Research group Termotecnia University of ValladolidValladolid47002Spain

An analysis of the sectorial structure of energy consumption shows that residential and tertiary sector buildings are the third-highest consumers,responsible for 29.5%of a city’s final energy *** Building Quality Control Laboratory of the Basque Government aims to promote quality,innovation,and sustainability in *** accomplish this goal,it has constructed an experimental facility with different energy generation technologies and a very versatile control system for testing different energy systems and operation *** this study,we tested a facility for supplying domestic hot water and heating for a multi-family house by means of a condensing boiler and an aerothermal heat pump(together with the corresponding control).This installation could reproduce the thermal demands required to be satisfied by the generation equipment through a programmed operation of the installation based on real ***,this installation was analyzed using thermoeconomics(TE)to solve problems unable to be solved using traditional energy analyses based on the First Law of *** problems include:(1)Determining the costs of the products of the installation based on physical criteria,(2)detecting the places where losses actually occur,evaluating their costs,and proposing cost-effective improvements,and(3)diagnosing issues in the *** a result,this paper suggests a solution to the preventive maintenance problems confronting the technical maintenance personnel for thermal installations in buildings by applying TE knowledge and using real data collected from sensors.

关键词： Experimental essay Energy savings in thermal systems Thermoeconomics Thermoeconomic costs Diagnosis