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It is a challenge to improve the long-term durability of Pd-based electrocatalysts for oxygen reduction reaction (ORR) in fuel cells. Herein, Pd/CeO2-C-T (T= 800 °C, 900 °C and 1000 °C) hybrid catalysts with metal-support interaction are prepared from Ce-based metal organic framework precursor. Abundant tiny CeO2nanoclusters are produced to form nanorod structures with uniformly distributed carbon through a calcination process. Meanwhile, both carbon and CeO2nanoclusters have good contact with the following deposited surfactant-free Pd nanoclusters. Benefited from the large specific surface area, good conductivity and structure integrity, Pd/CeO2-C-900 exhibits the best electrocatalytic ORR performance: onset potential of 0.968 V and half-wave potential of 0.857 V, outperforming those obtained on Pd/C counterpart. In addition, the half-wave potential only shifts 7 mV after 6000 cycles of accelerated durability testing, demonstrating robust durability.
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BACKGROUND: This study evaluated the clinical laboratory capacity for the diagnosis of Chlamydia trachomatis (CT) in China to provide recommendations to improve the diagnostic capacity and quality of this clinically important sexually transmitted disease. METHODS: An electronic questionnaire-based cross-sectional, survey study was conducted by the National Center for STD Control among different types of healthcare facilities in China from July to December 2021. RESULTS: The surveyed laboratory facilities were located in 332 cities in 31 provinces in China. A total of 4640 records from clinical laboratories were included in the data set for the final analysis. Less than half of the laboratories (41.6% [1931 of 4640]) performed the CT diagnostic test; of these, 721 laboratories (15.5% [721 of 4640]) carried out nucleic acid amplification test (NAAT) methods, and 1318 laboratories (28.4% [1318 of 4640]) performed antigen-based immunochromatographic assays. Most laboratories were equipped with biological safety cabinets (93.7% [4348 of 4640]), 49.2% (2283 of 4640) were equipped with fully automated nucleic acid extractors, and 55.2% (2560 of 4640) were equipped with polymerase chain reaction amplification instruments. The laboratories from Southern China or third-class hospitals (i.e., the highest rated hospitals) had the highest proportion using NAATs to diagnose CT among the surveyed health facilities. CONCLUSIONS: Advancing laboratories to use NAAT to detect CT should be phased step-by-step by different areas and levels of hospitals according to the current situation.
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Infecções por Chlamydia , Chlamydia trachomatis , Humanos , Chlamydia trachomatis/genética , Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/epidemiologia , Estudos Transversais , Laboratórios , Inquéritos e Questionários , Técnicas de Amplificação de Ácido Nucleico/métodos , China/epidemiologiaRESUMO
The application of electrochemical hydrodechlorination has been impeded due to the low utilization and activity of Pd catalyst. Herein, a series of Pd catalysts were prepared via the controllable evolution of Zn state during the pyrolysis of ZIF-8 nanosheet. Various forms of Pd with different chemical surroundings were generated upon the combined use of galvanic displacement and ion exchange process. Electrocatalytic hydrodechlorination of 4-chlorophenol was performed and the electrocatalytic hydrodechlorination efficiency of Pd/CN reaches 100% within 3 h at extra low Pd concentration. The coexistence of zero-valent Pd (Pd0) and nitrogen coordinated Pd (Pd-N) was verified by XAFS which provide multiple active sites for focusing on adsorbing H* and cracking C-Cl respectively. The synergetic effect between different chemical state of Pd for efficient hydrodechlorination of chloroaromatics and scheme for dexterous preparation of Pd based electrocatalyst are proposed and discussed.
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A sulfur doping strategy has been frequently used to improve the sodium storage specific capacity and rate capacity of hard carbon. However, some hard carbon materials have difficulty in preventing the shuttling effect of electrochemical products of sulfur molecules stored in the porous structure of hard carbon, resulting in the poor cycling stability of electrode materials. Here, a multifunctional coating is introduced to comprehensively improve the sodium storage performance of a sulfur-containing carbon-based anode. The physical barrier effect and chemical anchoring effect contributed by the abundant C-S/C-N polarized covalent bond of the N, S-codoped coating (NSC) combine to protect SGCS@NSC from the shuttling effect of soluble polysulfide intermediates. Additionally, the NSC layer can encapsulate the highly dispersed carbon spheres inside a cross-linked three-dimensional conductive network, improving the electrochemical kinetic of the SGCS@NSC electrode. Benefiting from the multifunctional coating, SGCS@NSC exhibits a high capacity of 609 mAh g-1 at 0.1 A g-1 and 249 mAh g-1 at 6.4 A g-1. Furthermore, the capacity retention of SGCS@NSC is 17.6% higher than that of the uncoated one after 200 cycles at 0.5 A g-1.
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Under the traditional processing theory "wine processing could promote the efficacy", Rhubarb after wine processing could treat the upper energizer diseases such as red swelling, and breath sores. Processing changes the medicinal properties of rhubarb, and thus results in different focuses in clinical application. In this study, a sensitive and specific method was developed for the determination of aloe-emodin, rhein and emodin in rats tissue. Rhubarb raw materials and its wine processed decoction were given to SD rats respectively by gavage administration, and then the contents of aloe-emodin, rhein and emodin in the tissues (heart, lung, brain, liver, kidney) were determined by HPLC-MS to explore the effect of wine processing on free anthraquinones in rat tissues. Experimental results showed that wine processing can significantly change the distribution of aloe emodin, rhein and emodin in rats in vivo, and the distribution of these components was increased in heart and lung tissues.There was no significant change of distribution in the liver and the kidney as compared with raw product group, and these three ingredients were not detected in the brain, indicating that aloe-emodin, rhein, emodin can not pass through the blood brain barrier.Therefore, wine processing had greater effect on distribution of free anthraquinones in rat tissues.This also verified the theory of traditional Chinese medicine, providing experimental basis for rhubarb processing mechanism.
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Antraquinonas/farmacocinética , Emodina/farmacocinética , Rheum/química , Animais , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual , VinhoRESUMO
BACKGROUND: Although Mycoplasma genitalium (MG) is a common sexually transmitted infection (STI), very little information regarding the prevalence of MG among MSM (men who have sex with men) is available in China. The objective of this study was to determine the prevalence of MG among MSM in the city of Shenzhen, Guangdong Province, China, and to identify the potential risk factors associated with MG infection in this population. METHODS: Between January and May 2010, a total of 409 MSM were recruited in Shenzhen, Guangdong Province, China. An anonymous questionnaire was used to collect information regarding their sociological and sexual behaviors. In addition, their first-void urine (FVU) samples and rectal swabs were collected for PCR-based MG testing. RESULTS: Among the 406 FVU and 405 rectal swab samples were collected from 409 MSM, the overall MG prevalence was 8.1% (33/406, 95% CI 5.7%-10.6%), with a FVU positivity of 3.4% (95% CI 1.7%-5.4%) and a rectal positivity of 5.4% (95% CI 3.5%-7.7%). Using both univariate and multivariable logistic regression analyses, urethral MG infection was significantly associated with having more heterosexual behaviors (AOR 7.16, 95% CI 1.89-27.13), and with having unprotected anal intercourse in the past six months (AOR 4.80, 95% CI 1.40-16.47). Rectal MG infection was significantly associated with HIV infection based on univariate logistic regression analysis (OR = 4.49, 95% CI 1.18-17.12). CONCLUSIONS: In this study, we investigated the prevalence of MG infection in the population of interest, as determined from both urethral and rectal specimen. We showed that MG was more prevalent in MSM who had bisexual behaviors compared to those who engaged only in homosexual behaviors. Further work is needed to establish the mode of MG transmission and to identify its role in HIV transmission. Meanwhile, more attention should be paid to MG infection among MSMs, and especially bisexual MSMs, which might have critical implications for effective HIV/STD control in China.
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Infecções por HIV , Homossexualidade Masculina/estatística & dados numéricos , Infecções por Mycoplasma/epidemiologia , Mycoplasma genitalium/isolamento & purificação , Infecções Sexualmente Transmissíveis/epidemiologia , Adolescente , Adulto , China/epidemiologia , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Mycoplasma/microbiologia , Prevalência , Reto/microbiologia , Fatores de Risco , Comportamento Sexual , Infecções Sexualmente Transmissíveis/microbiologia , Inquéritos e Questionários , Uretra/microbiologiaRESUMO
2,5-bis(hydroxymethyl)furan (BHMF) derived from 5-Hydroxymethylfurfural (HMF) through a hydrogenation process has extensive applications in the production of resins, polymers, and artificial fibers. However, screening out the candidate and then modulating the active site to optimize the catalyst for high yield of BHMF are currently insufficient. In this study, Gibbs free energy diagrams of the reduction of HMF on 13 metals were presented, along with the identification of the rate-determining step (RDS) with the highest reaction barrier for each metal. We attempted to construct a volcano plot for HMFRR reaction. Additionally, a strategy was proposed to adjust the reaction barriers of RDS by combining two appropriate metals. Further experiments confirmed that Pb with the lowest energy barrier exhibited the highest HMF conversion (BHMF selectivity) among single metals. The modified catalyst by doping Ag on Pb, further boosted the HMF conversion (BHMF selectivity) from 42.1 % (59.4 %) to 80.8 % (80.9 %), respectively. These results provide an approach to rationally design and construct the catalyst system for efficient conversion of HMF.
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Osteosarcoma (OS) is the most common primary malignant tumour of the bone with high mortality. Here, we comprehensively analysed the hypoxia signalling in OS and further constructed novel hypoxia-related gene signatures for OS prediction and prognosis. This study employed Gene Set Enrichment Analysis (GSEA), Weighted correlation network analysis (WGCNA) and Least absolute shrinkage and selection operator (LASSO) analyses to identify Stanniocalcin 2 (STC2) and Transmembrane Protein 45A (TMEM45A) as the diagnostic biomarkers, which further assessed by Receiver Operating Characteristic (ROC), decision curve analysis (DCA), and calibration curves in training and test dataset. Univariate and multivariate Cox regression analyses were used to construct the prognostic model. STC2 and metastasis were devised to forge the OS risk model. The nomogram, risk score, Kaplan Meier plot, ROC, DCA, and calibration curves results certified the excellent performance of the prognostic model. The expression level of STC2 and TMEM45A was validated in external datasets and cell lines. In immune cell infiltration analysis, cancer-associated fibroblasts (CAFs) were significantly higher in the low-risk group. And the immune infiltration of CAFs was negatively associated with the expression of STC2 (P < 0.05). Pan-cancer analysis revealed that the expression level of STC2 was significantly higher in Esophageal carcinoma (ESCA), Head and Neck squamous cell carcinoma (HNSC), Kidney renal clear cell carcinoma (KIRC), Lung squamous cell carcinoma (LUSC), and Stomach adenocarcinoma (STAD). Additionally, the higher expression of STC2 was associated with the poor outcome in those cancers. In summary, this study identified STC2 and TMEM45A as novel markers for the diagnosis and prognosis of osteosarcoma, and STC2 was shown to correlate with immune infiltration of CAFs negatively.
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Biomarcadores Tumorais , Neoplasias Ósseas , Peptídeos e Proteínas de Sinalização Intercelular , Aprendizado de Máquina , Osteossarcoma , Osteossarcoma/genética , Osteossarcoma/diagnóstico , Osteossarcoma/patologia , Humanos , Prognóstico , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Biomarcadores Tumorais/genética , Neoplasias Ósseas/genética , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/patologia , Regulação Neoplásica da Expressão Gênica , Glicoproteínas/genética , Glicoproteínas/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Perfilação da Expressão Gênica , Nomogramas , Transcriptoma , Curva ROC , Feminino , Hipóxia/genética , MasculinoRESUMO
A cross-sectional study that investigated the association between cervical infection of Chlamydia trachomatis, Neisseria gonorrhoeae, or Mycoplasma genitalium and infection with high-risk types of human papillomavirus among female sex workers in China found that the presence of cervical C. trachomatis or M. genitalium infection was independently associated with infection with certain high-risk types of specific high-risk human papillomavirus among this population.
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Chlamydia trachomatis/isolamento & purificação , Coinfecção/epidemiologia , Mycoplasma genitalium/isolamento & purificação , Infecções por Papillomavirus/complicações , Profissionais do Sexo/estatística & dados numéricos , Doenças Bacterianas Sexualmente Transmissíveis/complicações , Adulto , Colo do Útero/microbiologia , Colo do Útero/virologia , China/epidemiologia , Coinfecção/microbiologia , Coinfecção/virologia , Feminino , Humanos , Papillomaviridae/classificação , Papillomaviridae/genética , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/virologia , Risco , Doenças Bacterianas Sexualmente Transmissíveis/epidemiologia , Doenças Bacterianas Sexualmente Transmissíveis/microbiologia , Adulto JovemRESUMO
BACKGROUND: Sexually transmitted infections (STIs) have become a major public health problem among female sex workers (FSWs) in China. There have been many studies on prevalences of HIV and syphilis but the data about Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) infections are limited in this population in China. METHODS: A cross-sectional study was performed among FSWs recruited from different types of venues in 8 cities in China. An interview with questionnaire was conducted, followed by collection of a blood and cervical swab specimens for tests of HIV, syphilis, NG and CT infections. RESULTS: A total of 3,099 FSWs were included in the study. The overall prevalence rates of HIV, syphilis, NG and CT were 0.26%, 6.45%, 5.91% and 17.30%, respectively. Being a FSW from low-tier venue (adjusted odds ratios [AOR]=1.39) had higher risk and being age of ≥ 21 years (AOR=0.60 for 21-25 years; AOR=0.29 for 26-30 years; AOR=0.35 for 31 years or above) had lower risk for CT infection; and having CT infection was significantly associated with NG infection. CONCLUSIONS: The high STI prevalence rates found among FSWs, especially among FSWs in low-tier sex work venues, suggest that the comprehensive prevention and control programs including not only behavioral interventions but also screening and medical care are needed to meet the needs of this population.
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Infecções por Chlamydia/epidemiologia , Gonorreia/epidemiologia , Neisseria gonorrhoeae/isolamento & purificação , Profissionais do Sexo/psicologia , Adulto , Coleta de Amostras Sanguíneas , China/epidemiologia , Infecções por Chlamydia/sangue , Infecções por Chlamydia/transmissão , Chlamydia trachomatis/isolamento & purificação , Estudos Transversais , Feminino , Gonorreia/sangue , Gonorreia/transmissão , Infecções por HIV/sangue , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Humanos , Modelos Logísticos , Prevalência , Kit de Reagentes para Diagnóstico , Fatores de Risco , Profissionais do Sexo/estatística & dados numéricos , Inquéritos e Questionários , Sífilis/sangue , Sífilis/epidemiologia , Sífilis/transmissão , Doenças do Colo do Útero/sangue , Doenças do Colo do Útero/epidemiologiaRESUMO
OBJECTIVES: Screening for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) at both urogenital and extragenital sites has been recommended in many countries. Testing of the infections using pooled specimens from urogenital and extragenital sites offer the opportunity to shorten the testing time and reduce the testing cost. Ex-ante pooling is placing the original single-site specimens in a tube with transport media, while ex-post pooling is making a pool of the transport media from both anorectal and oropharyngeal specimens and the urine. This study aimed to conduct a multisite performance evaluation of two pool-specimen approaches (ex-ante and ex-post) in detection of CT and NG using the Cobas 4800 platform among men who have sex with men (MSM) in China. DESIGN: Diagnostic accuracy study. SETTING, PARTICIPANTS AND OUTCOME MEASURES: Participants were recruited from MSM communities at six cities in China. Two oropharyngeal and anorectal swabs collected by clinical staff and 20 mL first-void urine collected by the participant himself were used for evaluating sensitivity and specificity. RESULTS: A total of 1311 specimens were collected from 437 participants in six cities. The sensitivities of ex-ante pooling approach as compared with single-specimen approach (reference standard) were 98.7% (95% CI, 92.7% to 100.0%) for detection of CT and 89.7% (95% CI, 75.8% to 97.1%) for NG, and the specificities were 99.5% (95% CI, 98.0% to 99.9%) and 98.7% (95% CI, 97.1% to 99.6%), respectively. The sensitivities of ex-post pooling approach were 98.7% (95% CI, 92.7% to 100.0%) for CT and 100.0% (95% CI, 91.0% to 100.0%) for NG, and the specificities were 100.0% (95% CI, 99.0% to 100.0%) and 100.0% (95% CI, 99.1% to 100.0%), respectively. CONCLUSIONS: The ex-ante and ex-post pooling approaches show good sensitivity and specificity in detecting urogenital and extragenital CT and/or NG, indicating that these approaches can be used in epidemiological surveillance and clinical management of CT and NG infections, particularly among MSM population.
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Neisseria gonorrhoeae , Minorias Sexuais e de Gênero , Masculino , Humanos , Chlamydia trachomatis , Homossexualidade Masculina , ChinaRESUMO
BACKGROUND: Mycoplasma genitalium (MG) is one of the common causes of non-gonococcal urethritis (NGU) in men and is associated with cervicitis, endometritis, and pelvic inflammatory diseases (PID) in women. The prevalence of MG infection has been reported to be high among female sex workers (FSWs) in many countries, but limited information is known among this population in China. METHODS: From July to September 2009, venue-based FSWs were recruited in two cities (Wuzhou and Hezhou) of Guangxi Autonomous Region in southwest China. Information of socio-demographic and behavioral characteristics was collected by a questionnaire-based interview. Cervical specimens were obtained for detection of MG using a real-time polymerase chain reaction (PCR) assay targeting mgpA gene. RESULTS: The overall prevalence of MG infection among 810 FSWs was 13.2% (95% CI = 10.87%-15.52%). MG infection was significantly associated with less education (adjusted odds ratio (AOR) = 2.36, 95% CI = 1.15-4.87) consisting of junior high school or below, being single (AOR = 2.27, 95% CI = 1.42-3.62), migrant background (AOR = 2.03, 95% CI = 1.29-3.20), and absence of any STI symptoms in the previous year (AOR = 1.66, 95% CI = 1.09-2.52). CONCLUSIONS: MG infection was prevalent among FSWs in the study areas. This pattern of infection suggests that an increasing attention should be paid to MG screening and treatment in this high risk population.
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Infecções por Mycoplasma/epidemiologia , Mycoplasma genitalium/isolamento & purificação , Profissionais do Sexo/estatística & dados numéricos , Doenças do Colo do Útero/microbiologia , Adolescente , Adulto , China/epidemiologia , Cidades , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Fatores Socioeconômicos , Inquéritos e Questionários , Adulto JovemRESUMO
BACKGROUND: The aim of this study was to identify risk factors associated with the low anterior resection syndrome (LARS) and to construct a nomogram capable of predicting the risk of LARS in patients who undergo rectal cancer resection. METHODS: About 538 patients who had undergone anterior resection were recruited as a development set. In addition, 114 patients with rectal cancer were analysed as a validation set to test the new nomogram. Patients in the development set were grouped into two separate cohorts: those with major LARS and those with minor or no LARS. Multiple logistic regression was conducted to detect risk factors for major LARS. RESULTS: The prevalence of major LARS was 40.7%, of minor LARS was 28.6% and the proportion with no LARS was 30.7% in the development set. In multivariate analysis, female gender, preoperative chemoradiation, low tumour height, diverting ileostomy, postoperative anastomotic leakage were shown to be independently associated with major LARS occurring in patients after rectal cancer resection. The area under the curve (AUC) values of the nomogram were 0.726 (95% CI: 0.682-0.769) and 0.750 (95% CI: 0.655-0.845) in the development and validation sets, respectively. The calibration curves and Hosmer-Lemeshow goodness of fit tests showed that the model was acceptably accurate. CONCLUSION: A nomogram model based on risk factors could be valuable as a predictor of the probability of major LARS after rectal cancer surgery, and provides a guide that clinical staff can use to take preventive measures for high-risk patients.
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Neoplasias Retais , Humanos , Feminino , Neoplasias Retais/patologia , Nomogramas , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Síndrome de Ressecção Anterior Baixa , Estudos Retrospectivos , Qualidade de VidaRESUMO
INTRODUCTION: Chlamydia trachomatis (CT) causes the most prevalent bacterial sexually transmitted infection in the world, and men who have sex with men (MSM) are considered as a high-risk population for this infection. Data regarding the prevalence of CT infection in China are limited and fragmented. In this study, we aim to determine at the national level the anatomically specific CT prevalence and genotype distribution of CT strains among MSM, recruiting from the venues where MSM commonly seek sexual partners. METHODS AND ANALYSIS: The study will be a nationwide cross-sectional survey to estimate the prevalence of chlamydial infections among MSM who meet the inclusion criteria over a period of 6 months (May-October 2022). A total of 2429 participants will be recruited from the venues where MSM most often seek sex partners in 14 cities of the 7 geographical regions in China. A mobile phone app-based anonymous self-administered questionnaire will be used to collect sociodemographic and behavioural data, and specimens of urine, anorectal and pharyngeal swabs will be collected for identifying the infections of CT and Neisseria gonorrhoeae and genotypes of CT. The data will be analysed using the IBM SPSS program V.20 ETHICS AND DISSEMINATION: The study protocol has been approved by the Medical Ethics Committee of the Chinese Academy of Medical Sciences Institute of Dermatology and the National Center for STD Control on 9 October 2021 (approval number 2021-KY-037). The study is based on voluntary participation and a written informed consent process. The study results will be submitted for publication in peer-reviewed journals and reported in conferences. The relevant data will be made available to development of control programmes and used as health education materials to disseminate to the community. The dataset will be deposited in a public repository. TRIAL REGISTRATION NUMBER: ChiCTR2100052869.
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Infecções por Chlamydia , Gonorreia , Minorias Sexuais e de Gênero , Infecções por Chlamydia/epidemiologia , Infecções por Chlamydia/microbiologia , Chlamydia trachomatis/genética , Efeitos Psicossociais da Doença , Estudos Transversais , Feminino , Gonorreia/epidemiologia , Homossexualidade Masculina , Humanos , Masculino , Neisseria gonorrhoeae/genética , PrevalênciaRESUMO
BACKGROUND: Little is known about rectal Chlamydia trachomatis (CT) infection in outpatients attending sexually transmitted disease (STD) clinics in China. In this study, we aimed to explore the clinical and epidemiologic features of rectal CT infection in this population. METHODS: A cross-sectional study was conducted among patients attending STD clinics in Tianjin and Guangxi provinces of China from June 2018 to August 2020. Bivariate and multivariate logistic regression analysis were developed to explore the association of different risk factors for urogenital and rectal CT infection. RESULTS: The prevalence of urogenital and rectal CT was 11.2% (154/1374) and 4.9% (68/1377), respectively. The rectal CT prevalence among female and male patients was 7.8% (60/767) and 1.3% (8/610), respectively. The most common genotype in urogenital CT-positive samples was genotype E (29.9%), while the most common genotype among rectal CT-positive samples was genotype J (23.4%). More than 85% (52/60) of women infected with rectal CT were co-infected with urogenital CT. About 90.0% (36/40) of women shared similar genotypes between rectal and urogenital samples. Females and patients infected with urogenital CT were deemed to be at an increased risk for rectal CT infection. A high proportion of rectal CT infection had concurrent urogenital CT infection, especially in women, and most of the co-infections were shared among the same genotypes. CONCLUSIONS: It would be prudent to encourage awareness and introduce detection tests and treatment strategies for rectal CT infection particularly in female patients visiting STD clinics in China.
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Metal-organic frameworks (MOFs) have attracted increasing attention as a promising electrode material for the oxygen evolution reaction (OER). Comprehending catalytic mechanisms in the OER process is of key relevance for the design of efficient catalysts. In this study, two types of Co based MOF with different organic ligands (ZIF-67 and CoBDC; BDC=1,4-benzenedicarboxylate) are synthesized as OER electrocatalysts and their electrochemical behavior is studied in alkaline solution. Physical characterization indicates that ZIF-67, with tetrahedral Co sites, transforms into α-Co(OH)2 on electrochemical activation, which provides continuous active sites in the following oxidation, whereas CoBDC, with octahedral sites, evolves into ß-Co(OH)2 through hydrolysis, which is inert for the OER. Electrochemical characterization reveals that Co sites coordinated by nitrogen from imidazole ligands (Co-N coordination) are more inclined to electrochemical activation than Co-O sites. The successive exposure and accumulation of real active sites is responsible for the gradual increase in activity of ZIF-67 in OER. This work not only indicates that CoMOFs are promising OER electrocatalysts but also provides a reference system to understand how metal coordination in MOFs affects the OER process.
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Polyoxometalate encapsulated by metal-organic framework (POM@MOF) hybrid is an ideal precursor for electrocatalysts because it provides a homogeneous catalyst system with a flexible synergistic effect. However, controlling its fine structures to activate the derived catalyst after pyrolysis remains a challenge. The uniformly distributed carbon-defect tungsten oxides on the 3D carbon matrix were synthesized by using phospho-tungstic acid confined in HKUST-1 (PA@HKUST-1) as the precursor. By choosing ethanol as the solvent, the framework of PA@HKUST-1 was retained integrally and each pore of HKUST-1 kept intact even with holding the PA molecule inside. The well-organized structure of PA@HKUST-1 facilitated to offer a highly distributed metal source, and further transform into defect-rich catalyst. The average size of the resulting WOxCy/C catalysts was 1.5 nm, which was similar to a single molecule of PA. The WOxCy/C catalysts exhibited superior activity in the methanol oxidation reaction after being platinized due to the enhanced resistance to CO poisoning, which is also confirmed by DFT. This finding suggests a new route to design and achieve the defect-rich catalyst with controllable size.
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BACKGROUND: Previous studies have investigated rectal Mycoplasma genitalium (MG) in men who have sex with men (MSM), while little is known about the prevalence of rectal MG infection in individuals attending sexually transmitted disease (STD) clinics in China. We aimed to estimate the prevalence of rectal MG infection in this population and identified the potential risk factors for rectal MG infection. METHODS: A cross-sectional study was conducted among individuals attending STD clinics located in China from June 2018 to August 2020. Univariate and multivariate logistic regression analyses were conducted to explore the association of different risk factors for rectal MG infection. RESULTS: A total of 1,382 patients were included in the final analyses. A total of 30 of 1377 rectal swabs (2.2%) and 77 of 1374 urogenital samples (5.6%) were positive for MG. In Guangxi, 18 of 47 patients (38.3%) infected with urogenital MG and 5 of 19 patients (26.3%) infected with rectal MG received the recommended treatment. Factors found to be significantly associated with rectal MG infection included: male (adjusted odds ratio (AOR) 0.232, [95% CI: 0.072-0.745]) compared to female, homosexual or bisexual (AOR 40.427, [95% CI: 3.880-421.196]) compared to heterosexual, and those infected with urogenital MG (AOR 7.215, [95% CI: 2.898-17.965]) compared to those who did not get infected with urogenital MG. CONCLUSION: Rectal MG infection should be thought of not only in MSM population but also in STD clinic patients, especially females who have urogenital MG infection. Appropriate strategy for rectal MG screening and treatment needs to be developed for these patients in China.
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Background: We aimed to evaluate the clinical performance of the GeneXpert® (Xpert) CT/NG assay for the detection of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) using urine and cervical swabs collected from patients in China. Methods: This study was conducted from September 2016 to September 2018 in three Chinese urban hospitals. The results from the Xpert CT/NG test were compared to those from the Roche cobas® 4800 CT/NG test. Discordant results were confirmed by DNA sequence analysis. Results: In this study, 619 first void urine (FVU) specimens and 1,042 cervical swab specimens were included in the final dataset. There were no statistical differences between the results of the two tests for the detection of CT/NG in urine samples (p > 0.05), while a statistical difference was found in cervical swabs (p < 0.05). For CT detection, the sensitivity and specificity of the Xpert test were 100.0% (95%CI = 96.8-99.9) and 98.3% (95%CI = 96.6-99.2) for urine samples and 99.4% (95%CI = 96.5-100.0) and 98.6% (95%CI 97.5-99.2) for cervical swabs, respectively. For NG detection, the sensitivity and specificity of the Xpert test were 99.2% (95%CI = 94.9-100.0) and 100.0% (95%CI = 99.0-100.0) for urine and 100% (95%CI = 92.8-100.0) and 99.7% (95%CI = 99.0-99.9) for cervical swabs, respectively. Conclusion: The Xpert CT/NG test exhibited high sensitivity and specificity in the detection of CT and NG in both urine and cervical samples when compared to the reference results. The 90-min turnaround time for CT and NG detection at the point of care using Xpert may enable patients to receive treatment promptly.
Assuntos
Infecções por Chlamydia , Gonorreia , Infecções por Chlamydia/diagnóstico , Chlamydia trachomatis/genética , Feminino , Gonorreia/diagnóstico , Hospitais Urbanos , Humanos , Neisseria gonorrhoeae/genética , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios XRESUMO
The continuous solid solution NiWOx is successfully prepared by using precursor W18O49 with plenty of oxygen defects. The NiWOx nanoparticles are characterized by X-ray diffraction, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and X-ray absorption spectroscopy. The crystallographic phase of NiWOx is stable and characterized by the same feature of the parent lattice W18O49 even with various concentrations of dopant Ni which indicates the existence of oxygen defects. The NiWOx nanoparticles could be processed as the appropriate promoter after loading 10 wt % Pt. The Pt/NiWOx displays remarkable response for oxygen reduction reaction in alkaline medium compared with the commercial Pt/C. The analysis of the electrochemistry data shows that the existence of abundant oxygen defects in the solid solution NiWOx is the key factor for the improved ORR catalyst performance. Ni is effective in the catalysts because of its compatibility with W in the solid solution and its active participation in oxygen reduction reaction.