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Fullerene (C60) crystals have attracted considerable attention in the field of optoelectronic devices owing to their excellent performance as n-type semiconductor material. However, a challenge still remains unbeaten as to the continuous crystallization of non-solvated C60 single-crystal films with high coverage and uniform alignment using low-cost solution techniques. Here, a facile bar coating method is used to prepare ribbon-shaped non-solvated C60 crystals with a large area (up to centimeters) and high coverage (>95%) by precisely controlling the crystallization process from specific solvents. Benefiting from the non-solvated crystalline structure, well-distributed thickness, uniform morphological alignment, and crystallographic orientation, organic field-effect transistors fabricated from the C60 single-crystal films exhibit a high average electron mobility of 2.28 cm2 V-1s-1, along with the coefficient of variance (CV) as small as 13.6%. This efficient manufacturing method will lay a strong foundation for C60 single-crystal films to fit into the future high-performance integrated optoelectronic application.
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The spring system functions as a pivotal element of the check valve, with its compression performance significantly influencing the valve's time, flow stability, and other characteristics. Taking cues from conventional springs, a refined rectangular helical spring with integrated support features was thoroughly evaluated for its compression performance. The design approach for this spring was elucidated, encompassing the utilization of the Finite Element Method (FEM) to model its compression behavior. Additionally, a laboratory configuration was implemented to authenticate the findings derived from the FEM simulation. Subsequently, a comparative investigation was carried out between an engineered spring and a conventional spring subjected to analogous processing. The comparative analysis unveiled that the support-featured spring exhibited a diminished lateral offset of 2.84 mm (equivalent to a reduction of 10.1 %) and a force-displacement curve with narrower vibration intervals and smaller amplitudes. Moreover, it exhibited an enhanced force feedback of 17.5 % under identical compression displacement conditions.
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The determination of cesium ions (Cs+) is important for various applications, including resource utilization, environmental monitoring, and human health. Electrochemical sensors, with their inherent advantages, stand out as an ideal choice for Cs+ detection. However, electrode materials for Cs+ sensors usually face problems such as poor selectivity and complex synthesis. Herein, a method employing nickel hexacyanoferrate (NiHCF) as the electrode material for stripping voltammetry in the determination of Cs+ was proposed. Both adsorption and electrochemical intercalation exhibited selectivity. In the presence of interfering ions at a 10 : 1 molar ratio to Cs+, Cs+ was still preferentially intercalated in NiHCF. However, electrochemical intercalation exhibits superior selectivity for Cs+ compared to adsorption. Meanwhile, the effect of adsorption on the detection was minimized by electrochemical intercalation. Based on the standard addition method, Cs+ was determined using both adsorption and electrochemical intercalation methods. The error reduced significantly from 32.7% above the theoretical value through adsorption to 9.5% below the theoretical value through electrochemical intercalation. This approach not only enhanced the measurement accuracy but also reduced the costs associated with both measurement and preparation. The study proposed a cost-effective and rapid method for Cs+ measurement using Prussian blue analogs.
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Accurate diagnostic techniques and effective therapeutic methods are required to treat H. pylori. The application of chicken single-chain variable fragment (scFv) antibodies may diagnose and treat H. pylori. This study used the phage display technique to construct a chicken-derived immune scFv antibody library against H. pylori. Total RNA was extracted from the spleens of five immunized chickens and reverse transcribed into cDNA. A fragment of scFv was produced by overlap extension PCR and cloned into a pHEN2 phagemid vector. After the package with the M13KO7 helper phage, the recombinant HpaA protein was used as a target antigen to validate the screening ability of our antibody library by bio-panning. The dilution counting results showed that the size of the primary antibody library was estimated to be 1 × 109 cfu/mL. PCR analysis of 47 clones from the library revealed that about 100% of the clones were positive with scFv fragments, and there were no identical sequences, indicating the good diversity of the antibody library. After three rounds of bio-panning, high-affinity antibodies against recombinant HpaA protein were successfully obtained. The selected antibody specifically recognized HpaA protein in nine different H. pylori strains, confirming the screening ability of our library. The chicken immune scFv antibody library against H. pylori was successfully constructed, and the antibody library's screening ability was validated by selecting specific scFv antibodies against recombinant HpaA and clinical strains. It provided a simple and rapid method to obtain antibodies against H. pylori for diagnosis or treatment.
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Spent ternary lithium-ion batteries contain abundant lithium resource, and their proper disposal is conducive to environmental protection and the comprehensive utilization of resources. Separating valuable metals in the ternary leaching solution is the key to ensuring resource recovery. However, the traditional post-lithium extraction strategies, which heavily rely on ion exchange to remove transition metal ions in the leachate, encounter challenges in achieving satisfactory lithium yields and purities. Based on this, this paper proposed a new strategy to prioritize lithium extraction from ternary leachate using "(+) LiFePO4/FePO4 (-)" lithium extraction system. The preferential recovery of lithium can be realized by controlling the potential over 0.1 V versus Standard Hydrogen Electrode (SHE) without introducing any impurity ions. The lithium recovery rate reaches 98.91%, while the rejection rate of transition ions exceeds 99%, and the separation coefficients of lithium to transition metal ions can reach 126. Notably, the resulting lithium-rich liquid can directly prepare lithium carbonate with a purity of 99.36%. It provides a green and efficient strategy for the preferential recovery of lithium from the spent ternary leachate.
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A predictive model was proposed for determining the high-temperature free height of perfluoroalkoxy alkane springs in air-operated double-bellow pumps with the aim of investigating their relaxation. The model incorporates classical spring deformation theory and considers the material, structure, and real-world operating conditions of the perfluoroalkoxy alkane springs. Experimental validation of the model is also conducted. This study examines the effects of varying temperatures and pre-compression values on the relaxation of perfluoroalkoxy alkane springs' free height. It collects relaxation curves under different temperatures and various pre-compression conditions. The results indicate that spring relaxation increases with higher temperatures when there is no pre-compression. Furthermore, increasing pre-compression at the same temperatures leads to greater spring relaxation. Pre-compression has a more significant impact on spring relaxation. By comparing the experimental data with the simulated curve generated by the model, it is evident that the predicted spring free height relaxation closely aligns with the actual measurements. This verification demonstrates the effectiveness and accuracy of the proposed model in evaluating the relaxation of perfluoroalkoxy alkane springs' free height. Moreover, the model provides a valuable tool for predicting the lifespan of similar perfluoroalkoxy alkane springs in engineering applications.
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Determination of lithium ions is very important for extraction of lithium from salt lakes. Electrochemical sensor is an ideal choice, but it is not available so far. Here, a voltammetric sensor based on lithium iron phosphate (LiFePO4) was developed. Single-crystal LiFePO4 dominated by the (010) lattice plane was synthesized using hydrothermal method; it had good selectivity for lithium ions. Lithium ions were preferentially intercalated into LiFePO4 even if molar ratio of sodium ions, potassium ions, magnesium ions or calcium ions to lithium ions reached 10:1. The intercalation and deintercalation of interfering ions should be avoided because this reduced the selectivity of LiFePO4 for lithium ions. Lithium ion concentration of synthetic Uyuni Salt Lake solution was determined using the standard addition method. The measurement result was only 0.34 % higher than the theoretical value. The sensor provides a highly selective lithium ion analysis method at an extremely low cost, which was very promising to be widely used.
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Revealing the stimuli-responsive mechanism is the key to the accurate design of stimuli-responsive luminescent materials. We report herein the multistimuli-responsive multicolor solid-state luminescence of a new dicopper(I) complex [{Cu(bpmtzH)}2(µ-dppa)2](ClO4)2 (1), and the multistimuli-responsive mechanism is clarified by investigating its four different solvated compounds 1·2CH3COCH3·2H2O, 1·2DMSO·2H2O, 1·4CH3OH, and 1·4CH2Cl2. It is shown that luminescence mechanochromism is associated with the breakage of the hydrogen bonds of bmptzH-NH with counter-ions such as ClO4- induced by grinding, while luminescence vapochromism is attributable to the breaking and forming of hydrogen bonds of dppa-NH with solvents, such as acetone, dimethylsulfoxide, and methanol, caused by heating and vapor fuming. In addition, those results might provide new insights into the design and synthesis of multistimuli-responsive multicolor luminescent materials by using various structure-sensitive functional groups, such as distinct N-H ones, to construct switchable hydrogen bonds.
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Campylobacter is among the four main causes of gastroenteritis worldwide. Most reported Campylobacter infections are caused by C. jejuni and C. coli. However, other emerging Campylobacter pathogens have been recognized as important pathogens in humans and animals. A novel bacterial strain, PS10T, was isolated from the gastric mucous of pigs in 2022 in Beijing, China. The cell was Gram-negative, microaerobic, motile, and negative for catalase, oxidase, and urease. Phylogenetic and phylogenomic analyses based on the 16S rRNA gene and core genome indicated that this isolate belongs to the genus Campylobacter. There were low dDDH relatedness and ANI values shared within this strain and its closest species C. mucosalis below the cut-off values generally recognized for isolates of the same species. The draft genome size of PS10T is 2,240,910 bp in length with a percentage of DNA G+C contents of 37.72%. Comparing the phenotypic and phylogenetic features among this isolate and its related organisms, strain PS10T represents a novel species within the genus Campylobacter, for which the name Campylobacter gastrosuis sp. nov. (Type strain PS10T = GDMCC 1.3686T = JCM 35849T) is proposed.
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Introduction: Spontaneous low-frequency oscillations play a key role in brain activity. However, the underlying mechanism and origin of low-frequency oscillations remain under debate. Methods: Optical imaging and an electrophysiological recording system were combined to investigate spontaneous oscillations in the hemodynamic parameters and neuronal activity of awake and anesthetized mice after Nω-nitro-L-arginine methyl ester (L-NAME) administration. Results: The spectrum of local field potential (LFP) signals was significantly changed by L-NAME, which was further corroborated by the increase in energy and spatial synchronization. The important finding was that L-NAME triggered regular oscillations in both LFP signals and hemodynamic signals. Notably, the frequency peak of hemodynamic signals can be different from that of LFP oscillations in awake mice. Discussion: A model of the neurovascular system was proposed to interpret this mismatch of peak frequencies, supporting the view that spontaneous low-frequency oscillations arise from multiple sources.
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Semiconductor cleaning system ultra-clean flow control pumps are critical equipment in the semiconductor industry. Among them, the perfluoroalkoxy alkane (PFA) spring is a pivotal component to control the pump, and its dynamic performance is crucial to ensure the efficient operation of the system. However, the dynamic performance of the spring is often affected by the operating frequency. This paper studied the effect of different working frequencies on the dynamic property of the spring through compression-cycle experiments under uniaxial sinusoidal excitation. The force-displacement curves under different compression frequencies were fitted to obtain the dynamic stiffness of the PFA spring under different cyclic loading frequencies. The variation in the spring's hysteresis coefficient was evaluated using the hysteresis curves of different cyclic loading conditions. After 2 million compression experiments, the changes in dynamic stiffness, hysteresis coefficient, and spring height were investigated. The obtained results revealed that, as the frequency increases, the dynamic stiffness of the spring increases. The hysteresis coefficient of the PFA spring is the largest at 10 Hz and the smallest at 6 Hz. Upon conducting 2 million compression tests, it was discovered that the dynamic stiffness experiences the greatest attenuation rate of 4.19% at a frequency of 8 Hz, whereas the hysteresis coefficient undergoes the largest attenuation of 42.1% at a frequency of 6 Hz. The results will help to improve the design and application level of PFA springs.
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Background: At present, the relationship between virulence factors of Helicobacter pylori (H. pylori) and gastrointestinal diseases is still under discussion. This study investigated the association between distinct virulence factors in H. pylori and different gastrointestinal diseases. Methods: Gastric biopsy specimens were obtained from 160 patients with different gastrointestinal diseases in China, including 77 patients with chronic gastritis (CG), 36 with peptic ulcer disease (PUD), and 38 with gastric carcinoma (GC). The presence of certain virulence genes was determined by polymerase chain reaction (PCR), and the results were analyzed using chi-squared tests. Results: A total of 160 H. pylori strains were successfully isolated from gastric biopsy specimens. Overall, all strains of H. pylori were cagA, cagE positive, and the most common vacA genotypes were s1 (98.8%) and m2 (68.1%). The positive rates of the jhp0562, jhp0563, homA, homB, hopQI, and hopQII genes were 99.4%, 32.5%, 33.1%, 71.3%, 100%, and 6.9%, respectively. There was no significant association between these genes and different disease types. The dominant hpyIIIR-positive genotype was detected in 83.1% of the strains, making it significantly more prevalent than the hrgA-positive genotype (P<0.001). Surprisingly, the mixed genotype of hrgA and hpyIIIR was common and accounted for 41.3%. The hrgA-positive strains were more common in GC patients (71.1%) compared to CG patients (50.7%, P<0.05). The mixed genotype was prevalent and accounted for 55.3% and 31.2% of strains from GC and CG patients, respectively. Multivariate analysis showed that the hrgA gene exhibited a positive correlation with GC and increased the risk of GC [odds ratio (OR) =3.606, P<0.05]. In contrast, the presence of hrgA exhibited a negative correlation with CG (OR =0.499, P<0.05). Conclusions: These results suggested that the universal presence of cagA, cagE, vacA s1, jhp0562, homB, and hopQI made it impossible to examine disease-specific associations with any of these virulence factors. In addition, they may synergistically contribute to more virulent strains and severe diseases in China. Furthermore, there was a strong association between the hrgA gene and progression to GC, indicating the potential application of other virulence factors in clinical detection.
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Pregnancy and lactation are a window period during which interventions on mothers bring beneficial effects to newborns. This study aims to investigate the effects of maternal supplementation with human-milk-derived Lactiplantibacillus plantarum WLPL04-36e during pregnancy and lactation on the physiology, immunity and gut microbiota of dams and their offspring. We found that after maternal supplementation, L. plantarum WLPL04-36e could be detected in the intestines and extraintestinal tissues (liver, spleen, kidneys, mammary gland, MLN and brain) of dams, as well as in the intestines of their offspring. Maternal supplementation with L. plantarum WLPL04-36e could significantly increase the body weights of dams and their offspring during the middle to late lactation period, elevate the serum levels of IL-4, IL-6, and IL-10 of dams and IL-6 level of offspring, and increase the proportion of spleen CD4+ T lymphocytes of the offspring. Moreover, L. plantarum WLPL04-36e supplementation could increase the alpha diversity of milk microbiota during early and middle lactation periods, and elevated the abundance of Bacteroides in the intestines of offspring at week 2 and week 3 after birth. These results suggest that maternal supplementation with human-milk-derived L. plantarum can regulate the immunity and intestinal microbiota composition of offspring and play positive roles in the growth of offspring.
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Microbioma Gastrointestinal , Leche Humana , Humanos , Recién Nacido , Embarazo , Femenino , Animales , Ratas , Interleucina-6 , Lactancia/fisiología , Suplementos DietéticosRESUMEN
Metronidazole (MNZ) is administered as first-line antibiotic for Helicobacter pylori eradication therapy; however, increasing resistance to MNZ impaired the efficacy. Increasing the dose of MNZ was recommended to overcome low-level resistance, but it was difficult to determine MNZ resistance level simply based on the rdxA gene mutation. In this study, the rdxA sequences of 511 clinical H. pylori strains were analyzed to assess the genotypes associated with MNZ resistance. We observed that the prevalences of rdxA sequences with missense, nonsense, and frameshift mutations were 70.25, 11.35, and 17.03%, respectively. Regarding the amino acid substitutions, T31E, H53R, D59N, L62V, S88P, G98S/N, R131K, and V172I were present in most strains regardless of the resistance phenotype. The correlation analysis showed R16H/C, Y47C, A67V/T, and V204I substitutions were associated with MNZ resistance. The mutation resulting in RdxA truncation was observed in 36.29% of the resistant strains, and 83.45% of these strains displayed high-level MNZ resistance (MIC > 256 µg/mL). Moreover, all strains with truncated mutation positions before amino acid 70 expressed high-level MNZ resistance. Our results indicated that most amino acid mutations probably contributed to the sequence diversity of RdxA, while R16H/C, Y47C, A67V/T, and V204I were potentially helpful to identify resistant strains. Although it was difficult to determine the mutations associated with MNZ resistance, the prediction of high-level resistance based on truncated characteristics of RdxA might be an important approach, which can effectively avoid H. pylori eradication therapy with unreasonable of MNZ dose increases for patients with high-level drug resistance. IMPORTANCE The increasing resistance to metronidazole impaired the efficacy of Helicobacter pylori eradication, and increasing the dose of metronidazole was recommended to overcome low-level resistance. For patients infected with highly resistant strains, the current empirical treatments, which generally used metronidazole in double doses or more, appeared impossibly to overcome the resistance and would only increase the incidence of adverse effects. Our results indicated that high-level metronidazole resistance was predominant, and almost half of the patients with high-level drug resistance could avoid usage of metronidazole based on the truncated mutations of RdxA sequences, which can effectively avoid H. pylori eradication therapy with unreasonable increases in the metronidazole dose.
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Purpose: To investigate whether rapid active molecular screening and infection prevention and control (IPC) interventions can reduce colonization or infection with carbapenem-resistant Enterobacterales (CRE) in a general emergency intensive care unit (EICU) without enough single-room isolation. Methods: The study was designed as a before-and-after quasi-experiment. Before the experimental period, the ward was rescheduled and the staff were trained. From May 2018 to April 2021, active screening was performed by seminested real-time fluorescent polymerase chain reaction (PCR) detection with rectal swabs from all patients on admission to the EICU, and the results were reported in 1 hour. Other IPC interventions including hand hygiene, contact precautions, patient isolation, environmental disinfection, environment surveillance, monitoring, auditing and feedback were conducted under strict supervision. The patients' clinical characteristics were collected simultaneously. Results: In this 3-year study, 630 patients were enrolled and 19.84% of the patients were initially colonized or infected with CRE as shown by active molecular screening. The average drug resistance ratio to carbapenem shown by clinical culture detection of Klebsiella pneumoniae (KPN) before the study was performed was 71.43% in EICU. The drug resistance ratio decreased significantly from 75%, 66.67% to 46.67% in the next 3 years (p<0.05) during which active screening and IPC interventions were strictly executed. While the ratio gaps between EICU and the whole hospital were narrowed from 22.81%, 21.11% to 4.64%. Patients with invasive devices, skin barrier damage, and the recent use of antibiotics on admission were found to have a higher risk of being colonized or infected with CRE (p<0.05). Conclusion: Active rapid molecular screening and other IPC interventions may significantly reduce CRE nosocomial infections even in wards without enough single-room isolation. The key to reduce the spread of CRE in the EICU is the strict execution of IPC interventions by all medical staff and healthcare workers.
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BACKGROUND: Application of chicken egg yolk immunoglobulin Y (IgY) for Helicobacter pylori (H. pylori, HP) has gained much interest in recent years. Comparing with for treatment, IgY may be more advantageous when used for H. pylori detection. METHODS: Nine strains of H. pylori with different genetic backgrounds were inactivated and used to immunize hens, respectively, for the preparation of polyclonal anti-H. pylori immunoglobulin Y (anti-HP IgY). The proteins of H. pylori with reactivity to anti-HP IgY were detected by Western Blot. The five protein bands that can be well recognized by anti-HP IgY of each group, and were prevalent in all nine strains were excised from SDS-PAGE gel, digested and identified by Nano-HPLC-MS/MS analysis. The potential of these identified proteins as antigen detection targets was then assessed by sequence analysis. RESULTS: Anti-HP IgY derived from each group of specific strain immunized hens can recognize self-strain and non-self-strain antigens well. Five immunodominant antigens were identified as chaperonin GroEL, flagellin A, urease subunit alpha, peroxiredoxin and DNA starvation/stationary phase protection protein. Sequences analysis showed that both peroxiredoxin and DNA starvation/stationary phase protection protein were present in all 1000 strains of H. pylori queried, and the amino acid sequences were highly conserved. The highest sequence consistency between the DNA starvation/stationary phase protection protein of H. pylori and non-Helicobacter organisms was 52.59%, and the consistent sites were scattered and there was no continuous long fragment consensus sequence. CONCLUSION: DNA starvation/stationary phase protection protein was identified as an immunodominant antigen of H. pylori and sequence analysis indicated that it could serve as a potential antigen target for the diagnosis of H. pylori infection.
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Infecciones por Helicobacter , Helicobacter pylori , Animales , Femenino , Epítopos Inmunodominantes , Pollos , Espectrometría de Masas en Tándem , Infecciones por Helicobacter/prevención & control , Anticuerpos Antibacterianos , ADNRESUMEN
Candida albicans remains the most common species causing invasive candidiasis. In this study, we present the population structure of 551 global C. albicans strains. Of these, the antifungal susceptibilities of 370 strains were tested. Specifically, 66.6% of the azole-nonsusceptible (NS)/non-wild-type (NWT) strains that were tested belonged to Clade 1. A phylogenetic analysis, a principal components analysis, the population structure, and a loss of heterozygosity events revealed two nested subclades in Clade 1, namely, Clade 1-R and Clade 1-R-α, that exhibited higher azole-NS/NWT rates (75.0% and 100%, respectively). In contrast, 6.4% (21/326) of the non-Clade 1-R isolates were NS/NWT to at least 1 of 4 azoles. Notably, all of the Clade 1-R-α isolates were pan-azole-NS/NWT that carried unique A114S and Y257H double substitutions in Erg11p and had the overexpression of ABC-type efflux pumps introduced by the substitution A736V in transcript factor Tac1p. It is worth noting that the Clade 1-R and Clade 1-R-α isolates were from different cities that are distributed over a large geographic span. Our study demonstrated the presence of specific phylogenetic subclades that are associated with antifungal resistance among C. albicans Clade 1, which calls for public attention on the monitoring of the future spread of these clones. IMPORTANCE Invasive candidiasis is the most common human fungal disease among hospitalized patients, and Candida albicans is the predominant pathogen. Considering the large number of infected cases and the limited alternative therapies, the azole-resistance of C. albicans brings a huge clinical threat. Here, our study suggested that antifungal resistance in C. albicans could also be associated with phylogenetic lineages. Specifically, it was revealed that more than half of the azole-resistant C. albicans strains belonged to the same clade. Furthermore, two nested subclades of the clade exhibited extremely high azole-resistance. It is worth noting that the isolates of two subclades were from different cities that are distributed over a large geographic span in China. This indicates that the azole-resistant C. albicans subclades may develop into serious public health concerns.
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Antifúngicos , Candidiasis Invasiva , Humanos , Antifúngicos/farmacología , Candida albicans/genética , Filogenia , Pruebas de Sensibilidad Microbiana , Azoles , Farmacorresistencia Fúngica/genéticaRESUMEN
BACKGROUND: Parachutists are generally recognized as a "high-risk" group among military personnel. However, the findings came mostly from data analysis without soldiers as subjects. OBJECTIVE: This study aimed to investigate the injury prevalence in Chinese paratroopers on-site and determine the relationship between injury and risk factors encountered during parachuting and land-based training. METHODS: This study consisted of a field study with questionnaire and an experiment on muscle load during the simulated training exercise of platform jumping with surface electromyography (EMG), in which 7230 paratroopers and 38 soldiers were involved respectively. Chi-square test was used for the injury rate analysis, ANOVA and t-test for comparison of EMG data, and logistic regression for the analysis of multiple factors. Taking both intensity and time into consideration, jump-years (J-yrs) was used as a complex indicator for exposure to parachuting. Either injury per 1000 jumps or injured persons per 100 soldiers were calculated as injury prevalence. RESULTS: The overall injury rate among Chinese parachutists was found to be 13.9 injuries per 1000 parachute jumps and 24.5% based on personnel. The person-based injury rate increased with the exposure level significantly (χ2â=â142.06, 2-sided, Pâ<â0.05; trend test also significantly). Among the identified risk factors the uneven terrain was ranked as the most important one by logistic analysis. The EMG amplitude in MVE% increased with the platform height of all the 8 measured muscles and even reached 100% in 4 muscles, showing a high impact at landing. In addition, some characteristics of parachuting injury were also revealed by the injury type and site analysis. CONCLUSION: A dose-response relationship between parachuting and injury was observed significantly in the survey of Chinese paratroopers. Their injury rate was found to be relatively higher than the reported internationally. Landing impact as a critical point for injury seemed to be proved by the investigation and also the experiment with EMG measurement. It is suggested for future studies, to use the person-based injury rate, landing studied in work physiology and with consideration of different landing skills.
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Aviación , Personal Militar , Humanos , Pueblos del Este de Asia , Factores de RiesgoRESUMEN
The current increase in resistance to antifungal drugs indicates that there is an urgent need to explore novel antifungal drugs with different mechanisms of action. Phosundoxin is a biphenyl aliphatic amide using a TPP-targeting strategy which targets mitochondria. To provide insights into the antifungal activities of phosundoxin, the antifungal susceptibility testing of phosundoxin was conducted on 158 pathogenic fungi and compared to that of traditional azole drugs. Phosundoxin displayed a broad-spectrum antifungal activity on all the tested yeast-like and filamentous fungi ranging from 2 to 16 mg/L. In particular, azole-resistant clinical isolates of Candida albicans were susceptible to phosundoxin with the same MICs as azole-susceptible C. albicans. Transcriptome analysis on azole-resistant C. albicans identified 554 DEGs after treatment with phosundoxin. By integrating GO and KEGG pathway enrichment analysis, the antifungal activity of phosundoxin was related to impairment of mitochondrial respiratory chain function. Acute oral and percutaneous toxicity of phosundoxin to rats showed that the compound phosundoxin were mild toxicity and LD50 was above 5000 mg/kg body weight in rats. This study demonstrated the potential of phosundoxin as an antifungal agent for the treatment of common fungal infection and contributed to providing insights into the mechanisms of action of phosundoxin against C. albicans.
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Mycoplasma pneumoniae is a significant cause of community-acquired pneumonia, which is often empirically treated with macrolides (MLs), but, presently, resistance to MLs has been a matter of close clinical concern. This assay is intended to contribute to resistance detection of M. pneumoniae in clinical practice. A novel real-time PCR assay with two non-overlapping probes on the same nucleic acid strand was designed in this study. It could effectively detect all mutation types of M. pneumoniae in 23S rRNA at loci 2063 and 2064. The results were determined by the following methods: ΔCT < 0.5 for MLs-sensitive M. pneumoniae; ΔCT > 2.0 for MLs-resistant M. pneumoniae; 10 copies as a limit of detection for all types. For detection of M. pneumoniae in 92 clinical specimens, the consistency between the results of this assay and the frequently used real-time PCR results was 95.65%. The consistency of MLs resistance results between PCR sequencing and this assay was 100% in all 43 specimens. The assay could not only cover a comprehensive range of targets and have high detection sensitivity but is also directly used for detection and MLs analysis of M. pneumoniae in specimens.