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The purpose of this study was to examine the effect of neuromuscular electrical stimulation (NMES) immediate intervention training on the countermovement jump (CMJ) height and to explore kinematic differences in the CMJ at each instant. A total of 15 male students who had never received electrical stimulation were randomly selected as the research participants. In the first test, the CMJ performance was completed with an all-out effort. The second experiment was best performed immediately to complete the CMJ operation after NMES for 30 min. Both experiments used a high-speed camera optical capture system to collect kinematic data. The results of this experiment revealed that after im-mediate NMES training, neuromuscular activation causes post-activation potentiation, which increases the height of the center of gravity of the CMJ and affects the angular velocity of the hip joint, the velocity and acceleration of the thigh and the shank and the velocity of the soles of the feet. The use of NMES interventional training based on the improvement of technical movements and physical exercises is recommended in the future.

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Objective To understand the distribution of frequently isolated pathogenic bacteria from clinical speci-mens and their antimicrobial resistance changes in Hunan Province from 2012 to 2021,and to provide scientific evi-dence for the formulation and evaluation of antimicrobial clinical administration policies.Methods Species identifi-cation,selection of quality control strains and antimicrobial susceptibility testing agents were conducted according to the technical scheme of the China Antimicrobial Resistance Surveillance System(CARSS).Duplicate strains were excluded based on the principle of counting the first strain in each case.Statistical analysis was performed by WHO-NET 5.6 software.The the variations in constituent ratio and resistance rate of strains were analyzed with linear trend test,and the magnitude of change was described with Pearson correlation coefficient.Results From 2012 to 2021,the number of clinically isolated bacteria in the analysis increased from 82 759 to 312 914,with Gram-negative bacteria accounting for 69.5％-72.4％.The major Gram-positive bacteria were Staphylococcus aureus,Staphylo-coccus epidermidis,Streptococcus pneumoniae,Enterococcus faecalis and Enterococcus faecium,and the major Gram-negative bacteria were Escherichia coli,Klebsiella pneumoniae,Pseudomonas aeruginosa,Acinetobacter baumannii and Enterobacter cloacae.Isolation rate of Gram-positive bacteria increased yearly(r=0.022,P=0.001).Isolation rate of methicillin-resistant Staphylococcus aureus(MRSA)decreased from 34.3％to 24.8％.Isolation rates of vancomycin-resistant Enterococcus faecium and Enterococcus faecalis were less than 3％and 2％,respectively,presenting a downward trend.The detection rate of penicillin-resistant Streptococcus pneumoniae(PRSP)decreased from 5.6％to 1.0％.Except cefoperazone sulbactam,resistance rates of Escherichia coli to other tested antimicrobial agents showed decreasing trends(r＜0,P=0.001).Isolation rates of third-generation cephalo-sporin-resistant Escherichia coli(CTX/CRO-R-EC)and carbapenem-resistant Escherichia coli(CREC)decreased year by year(from 70.5％to 45.3％,and 12.2％to 2.0％,respectively).Resistance rates of Klebsiella pneumo-niae to imipenem and meropenem have increased year by year,reaching 9.1％and 11.0％respectively in 2021,while isolation rate of carbapenem-resistant Pseudomonas aeruginosa(CRPA)decreased from 28.5％to 15.0％.Resistance rates of Acinetobacter baumannii to most antimicrobial agents were 40％-60％,and remained relatively stable.Isolation rate of carbapenem-resistant Acinetobacter baumannii(CRAB)ranged from 39.5％ to 59.6％.Conclusion The clinical isolation rates of most important special antimicrobial-resistant bacteria have been decrea-sing year by year,while the resistance rate of Klebsiella pneumoniae to carbapenem agents gradually increased.Antimicrobial stewardship as well as the prevention and control of healthcare-associated infection on specific antimi-crobial-resistant bacteria should continue to be implemented in the future.The coverage and quality of antimicrobial resistance surveillance in H unan Province should continue to be improved.

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Objective To understand the distribution and antimicrobial resistance changes of bacteria isolated from pleural and peritoneal effusion in Hunan Province,and provide reference for correct clinical diagnosis and rational antimicrobial use.Methods Data reported by member units of Hunan Provincial Antimicrobial Resistance Survei-llance System from 2012 to 2021 were collected.Bacteria antimicrobial resistance surveillance method was imple-mented according to technical scheme of China Antimicrobial Resistance Surveillance System(CARSS),and WHO-NET 5.6 software was used to analyze the data of bacteria isolated from pleural and peritoneal effusion as well as antimicrobial susceptibility testing results.Results From 2012 to 2021,a total of 28 934 bacterial strains were iso-lated from specimens of pleural and peritoneal effusions from member units of Hunan Provincial Antimicrobial Re-sistance Surveillance System,with 5 752 strains from pleural effusion and 23 182 from peritoneal effusion.The top five bacteria isolated from pleural effusion were Escherichia coli(n=907,15.8％),Staphylococcus aureus(n=535,9.3％),Klebsiella pneumoniae(n=369,6.4％),Staphylococcus epidermidis(n=452,7.9％),and Staphy-lococcus haemolyticus(n=285,5.0％).The detection rate of methicillin-resistant Staphylococcus aureus(MR-SA)from pleural effusion was 24.3％-39.2％,and that of methicillin-resistant coagulase negative Staphylococcus(MRCNS)was 58.8％-77.1％.The top five bacteria isolated from peritoneal effusion were Escherichia coli(n=8 264,35.6％),Klebsiella pneumoniae(n=2 074,9.0％),Enterococcus faecium(n=1 458,6.3％),Staphylo-coccus epidermidis(n=1 383,6.0％),and Pseudomonas aeruginosa(n=1 152,5.0％).The detection rate of MRSA from peritoneal effusion was 22.1％-52.4％,which presented a decreasing trend(P=0.004).The detec-tion rate of MRCNS was 60.4％-79.4％.The resistance rates of Enterobacterales from peritoneal effusion to ce-fazolin,cefuroxime,ceftriaxone and cefepime all showed decreasing trends(all P＜0.05).Vancomycin-,linezo-lid-,and teicoplanin-resistant Staphylococcus strains were not found in pleural and peritoneal effusions.The resis-tance rates of Enterococcus faecium to most tested antimicrobial agents were higher than those of Enterococcus fae-calis.The resistance rates of Enterobacterales to imipenem and meropenem were ≤8.5％.The resistance rates of non-fermentative Gram-negative bacilli to imipenem and meropenem were ≤43.3％.Conclusion The data structure of Hunan Antimicrobial Resistance Surveillance System for pleural and peritoneal effusions from 2012 to 2021 is relatively complete.The constituent and antimicrobial susceptibility of isolated pathogenic bacteria vary in different years.

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Objective To understand the distribution and changes in antimicrobial resistance of clinically isolated Pseudomonas aeruginosa(P.aeruginosa)in the member hospitals of Hunan Provincial Antimicrobial Resistance Surveillance System from 2012 to 2021.Methods Antimicrobial susceptibility testing by disk diffusion or automa-ted instrument was performed on clinical isolates.Testing results were determined according to the standards of 2022 edition from American Clinical Laboratory Standards Institute(CLSI).Statistical analysis was performed by WHONET 5.6 software.Data were analyzed by trend test(Cochran-armitage)and Chi-square test with SPSS.Results A total of 176 441 strains of P.aeruginosa were surveilled by Hunan Provincial Antimicrobial Resistance Surveillance System from 2012 to 2021.99.4％of the strains were isolated from hospitalized patients,and about 70％of the strains were isolated from respiratory specimens.8.4％of P.aeruginosa were from children(0-17 years old),91.6％were from adults.Antimicrobial susceptibility testing results showed that P.aeruginosa was most sensitive to polymyxin B over 10 years,with a resis-tance rate of less than 6％.Resistance rates to piperacil-lin,piperacillin/tazobactam,ceftazidime,cefepime,aztreonam,imipenem,amikacin,gentamicin,tobramycin,cip-rofloxacin,levofloxacin,and polymyxin B all showed downward trends.A total of 29 920 carbapenem-resistant P.aeruginosa(CRPA)strains were detected.The average isolation rate of CRPA in this province was 18.0％over 10 years.CRPA detection rate from adult was 18.5％,higher than that from children(12.3％),and both showing downward trends.Conclusion The resistance rate of clinically isolated P.aeruginosa in Hunan Province to most commonly used antimicrobial agents is decreasing.

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Objective To understand the epidemiology of clinically isolated Acinetobacter baumannii(A.bauma-nnii)in Hunan Province.Methods Bacterial antimicrobial resistance surveillance was carried out according to the requirements of the technical program of National Antimicrobial Resistance Surveillance System.Clinical data of Acinetobacter spp.reported to Hunan Provincial Antimicrobial Resistance Surveillance System by multiple centers in Hunan Province from 2012 to 2021 were summarized and analyzed with reference to the standards of the American Clinical and Laboratory Standards Institute.Results A total of 169 438 strains of Acinetobacter spp.were detected during the 10-year period,with the detection rate of A.baumannii being the highest(82.74％).70 923 strains(53.63％)of carbapenem-resistant A.baumannii(CRAB)and 58 149 strains(43.97％)of carbapenem-sensitive A.baumannii(CSAB)were detected respectively.Both CRAB and CSAB were detected most frequently in the age group＞70 years,which were 34.44％and 32.02％,respectively.The percentage of CRAB and CSAB detected in the intensive care unit were 34.80％and 11.31％,respectively.CRAB and CSAB were mainly isolated from spu-tum/bronchoalveolar lavage fluid,followed by pus/secretion,urine,and blood.The resistance rates of CRAB to commonly used antimicrobial agents didn't change much during the 10-year period.Resistance rates of CRAB to ceftazidime and cefepime were both＞84％,to ampicillin/sulbactam and piperacillin/tazobactam were both＞82％,to aminoglycosides and quinolones were both＞59％,to minocycline and polymyxin B were 15.9％-25.0％and 1.3％-6.9％,respectively.CSAB were sensitive to commonly used antimicrobial agents.Conclusion The isolation rate of CRAB is high and there is no significant change in resistance to commonly used antimicrobial agents.

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Purpose: This study aimed to explore the impact of different landing methods on leg movement ability and the relationship between various parameters of leg movement. Methods: This work parameters including stride, contact time, flight time, duty factor, stride angle, vertical stiffness, leg stiffness and peak vertical ground reaction force. Thirty healthy subjects voluntarily participated in this study. In this experiment, each subject was required to perform two tests on a treadmill (using a speed of 10 km/h and 160 spm) (The interval between two experiments is 7 days). In the first test, subjects used RFS. In the second test, FFS was used. A high-speed video camera was used to collect the images and the Kwon3D motion analysis suite was used to process the images in this experiment. Results: The findings of this study revealed that runners employing the forefoot strike FFS method exhibited several favorable characteristics in contrast to those using the rearfoot strike RFS method. These included shorter contact time, longer flight time, reduced duty cycle, increased stride angle and heightened leg stiffness. Additionally, peak vertical ground reaction forces were significantly elevated in females. Conclusions: While rear foot strike RFS demonstrates a notable enhancement in leg stiffness among female runners with low leg stiffness, it concurrently leads to a significant increase in peak vertical ground reaction force and imposes a greater load on the legs. However, this phenomenon is not observed among male participants.

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This study aimed to explore the kinematic characteristics of males using various foot landing strategies. The participants were fifteen male students from Physical Education College, Huaibei (non-professional runners, who did not have a fixed running landing strategy mode) (mean height = 178.20 cm; mean weight = 67.60 kg; mean age = 19.40 years). In this experiment, the running model of different foot landing strategies (forefoot strike, FFS and rearfoot strike, RFS) were analyzed using two high-speed cameras captured simultaneously at a sampling rate of 100 Hz. According to the results, the runners with better sports performance have shorter contact time, longer flight time, lower duty factor, larger stride angle, faster V COG, greater A COG, and knee and ankle angles which were crucial kinematics factors to enhance the running. Therefore, this study recommends that coaches or researchers can use photography to analyze novice runners who do not have a fixed landing pattern when running with RFS, the characteristics of running style was closely related to the flight times, and running with FFS was closely related to the stride angle.

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The purpose of this study was to explore the utility of an 8-week rope skipping intervention in enhancing standing long jump performance was assessed by means of specific kinematic parameters acquired by 3-D space photography. The fifteen male college students from the physical education institute were randomly recruited as the research subjects. Participants first completed a standing long jump test without rope skipping intervention. Participants subsequently took part in a second standing long jump test after rope skipping training. Two high-speed digital cameras with 100 Hz sampling rate were synchronized to capture the movement. The captured images were processed using motion analysis suite, and the markers attached to joints on images were optical auto capture. Based on the results, the velocity of the center of gravity at take-off and landing were significantly improved. In addition, the study confirmed the requirement for forward tilt of the hip joint at landing to increase the velocity of the center of gravity and hence long jump distance. The detailed kinematic analysis described here provided further evidence of the benefits of integrating non-specialized and specialized training activities to enhance athletic performance and offers a contribution to movement theory and practice.

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The purpose of this study was to explore the kinematical characteristics of jumping discus throwing. Eight male right-handed discus throwers who used to practice the jumping throwing technique were recruited as participants. Two high-speed digital cameras with 120 Hz sampling rate were synchronized to capture the movement. The captured images were processed using a motion analysis suite, and the markers attached to joints on images were digitized manually. Based on the results, throwers should keep smaller the shoulder-hip twisting and the right anterior superior iliac spine (abbreviated: ASIS) in front of the right acromion (for right-handed throwers) from the instant the right foot lands to the instant the left foot lands, before the instant of the right foot lands; keep the discus at a depressed position; and reduce the time before discus release, particularly the time of the non-support phase and the second single-support phase. Additionally, release velocity must be improved because throwing distance is directly proportional to squared release velocity. In conclusion, the current study demonstrated comprehensive kinematical analyses, which can be used to instruct the jumping discus throwing technique with duration and angle characteristics of throwing movement for athletes by coaches with videos.

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Electrical contacts often dominate charge transport properties at the nanoscale because of considerable differences in nanoelectronic device interfaces arising from unique geometric and electrostatic features. Transistors with a tunable Schottky barrier between the metal and semiconductor interface might simplify circuit design. Here, germanium nanowire (Ge NW) transistors with Cu3 Ge as source/drain contacts formed by both buffered oxide etching treatments and rapid thermal annealing are reported. The transistors based on this Cu3 Ge/Ge/Cu3 Ge heterostructure show ambipolar transistor behavior with a large on/off current ratio of more than 105 and 103 for the hole and electron regimes at room temperature, respectively. Investigations of temperature-dependent transport properties and low-frequency current fluctuations reveal that the tunable effective Schottky barriers of the Ge NW transistors accounted for the ambipolar behaviors. It is further shown that this ambipolarity can be used to realize binary-signal and data-storage functions, which greatly simplify circuit design compared with conventional technologies.