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Traditional animal dung fuel use is a prominent source of brown carbon (BrC) in the Tibetan Plateau (TPL) region. Changes in burning conditions, fuel types, and uses of dung fuels in Plateau areas can lead to considerable uncertainties about molecular absorption properties and their radiative forcing influence on BrC. Here, the constituents of BrC’s chromophoric molecules emitted from residential heating and cooking scenarios using dung fuels were proposed using ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry in the TPL region, China. Our results show that dung fuels in this study can release abundant BrC emissions with substantial high BrC absorption when compared with those observed in bitumite. Particularly, the linkage between BrC molecules and their absorption properties was quantified by partial least squares regression. Among detected BrC’s molecular groups, above 70 % of N-containing compounds (CHON and CHONS) with low-oxygen-containing and unsaturated aromatic bonds and 20.9–27.5 % of CHO compounds measured from the dung combustion samples were lies in the potential BrC chromophores regions. Further, a significantly enhanced contribution of molecular absorption coefficient (Mbabs) to total Mbabs (up to 99.7 %) was observed in the presence of both CHO and CHON (N2+N4) with distinctive characteristics of long carbon chains and high levels of unsaturation. Interestingly, the identified CHONS markers were highly oxygenated with abundant unsaturated double-bonds and high Mbabs, but were rarely produced under insufficient oxygen conditions at the high-altitude plateau. Meanwhile, the incomplete combustion of dung produced high values of integrated simple forcing efficiency and thus destroyed the radiation balance over the TPL region.

We here described a ceftriaxone-resistant Neisseria gonorrhoeae FC428 clone (YL201) with moderate-level resistance to azithromycin in Shenzhen, South China in 2020. The NG-STAR type of YL201 is ST2238, containing a mosaic penA-60.001 allele, which is a typical characteristic of FC428 clone. YL201 harbours four copies of the 23S rRNA C2611T mutation, conferring moderate-level resistance to azithromycin. The MLST type is ST1600, identical with two N. gonorrhoeae FC428 clones identified in Hangzhou. Genome-wide phylogeny analysis demonstrates that YL201 is clustered with other FC428 clones from Hangzhou (South-east China) and Chengdu (South-west China). Isolates within this cluster have relatively higher MIC for ceftriaxone and display closely related MLST STs (ST1600 and ST7363) but are different from the ST of typical FC428 clone (ST1903). As ST1600 and ST7363 are common STs in Shenzhen, the further spread of FC428 clones may increase the severity of gonococcal resistance. In summary, identifying a multidrug-resistant (MDR) N. gonorrhoeae isolate in Shenzhen showed FC428 clones have undergone further transmission in China and presented more extensive and concerning antimicrobial resistance (AMR) characteristics during the spread.

Reactive oxygen species (ROS) play a central role in health effects of ambient fine particulate matter (PM

Ageing is an unavoidable process in humans and a major factor for the increasing risk of various diseases. In the United States, more than 50% of rheumatoid arthritis patients are middle-aged or elderly, but the risk factors and mechanisms by which ageing increases the incidence of rheumatoid arthritis are not known. It has been suggested that the accumulation of DNA fragments increases the risk of autoimmune diseases, such as systemic lupus erythematosus. DNA fragments are a common nucleic acid metabolite in ageing organisms as well as in the serum of humans and animals with rheumatoid arthritis; therefore, we hypothesize that DNA fragments are one of the factors contributing to the development of rheumatoid arthritis due to ageing. First, we analysed two in vitro DNA damage response models by using a gene silencing approach and determined that the DNA fragment clearance gene TREX1 can regulate inflammatory factor release in normal cells. Second, after TREX1 expression was knocked down locally or systemically in rats via the Cre-LoxP system and compared with that in AIA(adjuvant-induced arthritis) model rats treated with AAV-TREX1, it was determined that DNA fragments can result in manifestations of arthritis and abnormal activation of the immune system in rats. These results, including the low expression of the TREX1 gene in clinical patient and AIA model samples and the results of immunohistochemical, Western blot, and transcriptome analyses, revealed that the TREX1 gene can regulate cellular senescence-associated secretory phenotype (SASP)-related manifestations and showed that dysregulation of c-Jun and c-Fos, components of the TREX1 transcription factor AP-1, is associated with SASP induction. Finally, it was confirmed in vitro that different causes of decreased c-Fos expression can inhibit TREX1 expression. These DNA fragments are potent producers of inflammation-releasing mediators, and TREX1 is an effective degrader of DNA fragments; it is also a key gene that regulates cellular immunity and ageing. Therefore, effectively clearing excess DNA fragments from the body and ensuring the health of senescent cells may be a potential prevention strategy for RA.

In our recent effort of developing methylation-dependent endonuclease mediated methylation sequencing technology, efficiency and reproducibility were restrained by adapters’ self-ligation. In the present study, three strategies to prevent self-ligation of adapters used in enzyme mediated methylation sequencing have been developed. Our data have demonstrated that these strategies can either inhibit or eliminate the adapters’ self-ligation. These strategies are crucial in enzyme-mediated methylation sequencing and may be useful in some other genomic sequencing technologies.

Humic-like substances (HULIS) accounted for a great fraction of water-soluble organic matter (WSOM) in PM

Since timely determination of nvCT is critical for restricting further infection spread in the population, we have developed a screening assay based on high‐resolution melting (HRM) that can detect C. trachomatis and identify nvCT. Our results showed that the HRM scanning assay is not only able to directly identify C. trachomatis in clinical specimens, but also to correctly differentiate nvCT with mutation C1514T, C1515T and G1523A from the wild‐type., Summary Chlamydia trachomatis is the most common sexually transmitted pathogen globally, causing serious health problems and representing a burden on public health. A new variant of C. trachomatis (nvCT) that carries mutations (C1514T, C1515T and G1523A) in the 23S rRNA gene has eluded detection in Aptima Combo 2 assays. This has led to false negatives in diagnostics tests and poses a challenge for C. trachomatis diagnostics on a global level. In this study, we developed a simple and cost‐effective assay to identify C. trachomatis, with a potential application to screen for nvCT. We developed a screening assay based on high‐resolution melting (HRM), targeting the 23S rRNA gene and cryptic plasmid. To evaluate the performance of the assay, 404 archived C. trachomatis DNA specimens and 570 extracted clinical specimens were analysed. Our HRM assay not only identified C. trachomatis in clinical specimens, but also correctly differentiated nvCT carrying C1514T, C1515T and G1523A mutations from the wild‐type. We observed no cross‐reactions with other clinically related agents, and the limit of detection was 11.26 (95% CI; 7.61–31.82) copies per reaction. Implementation of this screening assay could reduce detection times and costs for C. trachomatis diagnoses, and facilitate increased research on the presence and monitoring of nvCT.

Background Antimicrobial resistance (AMR) of Neisseria gonorrhoeae has spread worldwide. Rapid and comprehensive methods are needed to describe N. gonorrhoeae AMR profiles accurately. A method based on multiplex amplicon sequencing was developed to simultaneously sequence 13 genes related to AMR in N. gonorrhoeae directly from clinical samples. Methods Nine N. gonorrhoeae strains were used for the establishment and validation of the method. Eleven urethral swabs and their corresponding cultured isolates were matched as pairs to determine the accuracy of the method. Mock samples with different dilutions were prepared to determine the sensitivity of the method. Five nongonococcal Neisseria strains and 24 N. gonorrhoeae negative clinical samples were used to evaluate the cross-reactivity. Finally, the method was applied to 64 clinical samples to assess its performance. Results Using Sanger sequencing as a reference method, sequences recovered from amplicon sequencing had a base accuracy of over 99.5% and the AMR sites were correctly identified. The limit of detection (LOD) was lower than 31 copies/reaction. No significant cross-reactivity was observed. Furthermore, target genes were successfully recovered from 64 clinical samples including 9 urines, demonstrating this method could be used in different types of samples. For clinical samples, the results can be obtained within a time frame of 7 h 40 min to 10 h 40 min, while for isolates, the turnaround time was approximately 2 h shorter. Conclusions This method can serve as a versatile and convenient culture-free diagnostic method with the advantages of high sensitivity and accuracy.

The emerging cephalosporin-resistant Neisseria gonorrhoeae poses an urgent threat to the continued efficacy of the last-line monotherapy for gonorrhea. Consequently, high-throughput, accurate, and reasonable molecular assays are urgently needed for strengthening antimicrobial-resistance surveillance in N. gonorrhoeae .

In this study, 3- or 4-h high time–resolved PM2.5 was observed during a severe winter haze–fog event (1 to 6 January 2017) to investigate the formation and evolution of parent polycyclic aromatic hydrocarbons (pPAHs) and oxygenated polycyclic aromatic hydrocarbons (OPAHs) in Xi’an, a typical city in northwestern China. Three episodes (episode I, episode II, and rainy day (EI, EII, and RD)) have been identified during this haze–fog event. Nine water-soluble ions, 8 carbonaceous fractions, 18 pPAHs, and 3 OPAHs in PM2.5 were measured. pPAHs showed two peaks at around 12:00 local standard time (LST) and 24:00 LST and two troughs at around 2:00 LST and 18:00 LST during EI. However, the OPAHs presented highest at around 18:00 LST and lowest at around 2:00 LST. During EII, pPAHs and OPAHs displayed similar diurnal variations with the highest values at noon but lowest values at around 2:00–5:00 LST. In addition, no obvious diurnal variations of pPAHs and OPAHs were observed during RD were absent during RD. Diurnal variations of pPAH ring distributions demonstrated coal combustion, and vehicle emissions contributed to pPAHs for three episodes, which is further confirmed by diagnostic ratio results. High oxygenation (Ro) rates were found during the sampling time, which favored OPAH formation. The study herein indicates that OPAH formation through complex atmospheric reactions provides us new insights into the severe haze–fog events.

Brown carbon (BrC), an aerosol carbonaceous matter component, impacts atmospheric radiation and global climate because of its absorption in the near-ultraviolet-visible region. Simultaneous air sampling was conducted in two megacities of Xi'an (northern) and Hong Kong (southern) in China in winter of 2016-2017. The aim of this study is to determine and characterize the BrC compounds in collected filter samples. Characteristic absorption peaks corresponding to aromatic C-C stretching bands, organo-nitrates, and C═O functional groups were seen in spectra of Xi'an samples, suggesting that the BrC was derived from freshly smoldering biomass and coal combustion as well as aqueous formation of anthropogenic secondary organic carbon. In Hong Kong, the light absorption of secondary BrC accounted for 76% of the total absorbances of BrC. The high abundance of strong C═O groups, biogenic volatile organic compounds (BVOCs) and atmospheric oxidants suggest secondary BrC was likely formed from photochemical oxidation of BVOCs in Hong Kong. Several representative BrC molecular markers were detected using Fourier transform ion cyclotron resonance mass spectrometry and their absorption properties were simulated by quantum chemistry. The results demonstrate that light absorption capacities of secondary anthropogenic BrC with nitro-functional groups were stronger than those of biogenic secondary BrC and anthropogenic primary BrC.

At present, the automatic driving system is accelerating the evolution from L2 assistant driving system to L5 with the advanced automatic driving function in full scenarios. The drivers’ trust in automated driving systems has been proved to be one of the most important factors that affect drivers’ acceptance of automated driving technology. It is also a primary determinant of understanding how to promote productive interaction between drivers and automated driving systems. This paper presents two mixed-method studies that combine demographic and experimental methodologies to assess trust in AVs. 1131 drivers with different driving experiences were investigated on their initial trust in AVs through an online questionnaire. Twenty-six participants evaluated dynamic trust in six sessions of varying road complexity in an L3 automated driving simulator. Data collected included subjective measures of trust, behavior, and physiological measures through ECG and GSR. The results show that drivers’ initial trust related to individuals’ disposition includes age, driving years, gender, driving experience, perceived risks, acceptance of new technology, and the perception of risk. As well as drivers’ initial learned trust depends on the understanding of AVs technology, driving capacity, and the experience of AVs. The dynamic trust changes with the understanding of AVs performance and the external environment. For higher-risk events such as pedestrians and obstacles, the audible reminder can effectively enhance drivers’ situational awareness and trust as a strong reminder to supplement the visual channel in automated driving systems. These findings provide an effective basis for further research and design related to improving the trust in AVs.

Rheumatoid arthritis (RA) is a chronic systemic inflammatory disorder which is associated with the dysregulation of autoimmune response. In recent years, early diagnosis, aggressive treatment and alternative therapeutic options of disease-modifying anti-rheumatic drugs (DMARDs) markedly improve both the management and long-term prognosis of RA. Since the discovery of non-coding RNA (ncRNA) including microRNA (miRNA), long non-coding RNA (lncRNA) and others, their altered expressions have been unraveled to be deregulated in various diseases including RA. Several lines of evidence are emerging that ncRNA may contribute to the pathogenesis, disease progression and treatment of RA. For example, SNP rs2850711 within lnc00305 was indicated to associate with RA development susceptibility, whereas a higher level of miR-10a represented a good response to methotrexate (MTX) treatment in RA patients. In the aspect of refractory RA, ncRNA also plays an important role by affecting or regulating drug sensitivity in RA patients. Of note, lower expression of miR-20a in rheumatoid arthritis synovial fibroblast (RASFs) was demonstrated to activate the Janus Kinase (JAK)- signal transducer and activator of transcription 3(STAT3)-mediated inflammation, thereby promoting cell proliferation and apoptosis-resistant. In this review, we have illustrated the changes of ncRNAs and their underlying mechanisms in the whole developing period of RA pathogenesis and disease progression, as well as highlighted the novel therapeutic targets/strategies and bio-markers for RA therapy.

Residential coal combustion is a prominent source of brown carbon (BrC) aerosols, but knowledge of their molecular structures and optical absorption were limited, which have notable used in ambient BrC source identification and radiative forcing calculation. In this study, the Fourier transform-ion cyclotron resonance mass spectrometry combined with partial least squares regression analysis as well as Fourier transform infrared spectroscopy analysis were used to insight the molecular compounds and structures of BrC from anthracite and bituminous coal combustions between traditional and improved stoves. The absorption Ångström exponents (AAE) and mass absorption efficiency (MAE) values for the BrC emitted from the combinations of bituminous were both 1.2-2.5 times lower than those of anthracite, interpreting that the BrC from the anthracite emissions had greater light-absorbing capacity. In contrast, the emission factor of light absorption (EF

Curcumin nicotinate (Curtn) is a synthesized ester derivative of curcumin and niacin. Our previous study has shown that Curtn lowers serum low-density lipoprotein cholesterol (LDL-C) levels in apoE

Gonorrhea is one of the most common sexually transmitted diseases worldwide. To cure infection and prevent transmission, timely and appropriate antimicrobial therapy is necessary. Unfortunately, Neisseria gonorrhoeae, the etiological agent of gonorrhea, has acquired nearly all known mechanisms of antimicrobial resistance (AMR), thereby compromising the efficacy of antimicrobial therapy. Treatment failure resulting from AMR has become a global public health concern. Whole-genome sequencing is an effective method to determine the AMR characteristics of N. gonorrhoeae. Compared with next-generation sequencing, the MinION sequencer (Oxford Nanopore Technologies (ONT)) has the advantages of long read length and portability. Based on a pilot study using MinION to sequence the genome of N. gonorrhoeae, we optimized the workflow of sequencing and data analysis in the current study. Here we sequenced nine isolates within one flow cell using a multiplexed sequencing strategy. After hybrid assembly with Illumina reads, nine integral circular chromosomes were obtained. By using the online tool Pathogenwatch and a BLAST-based workflow, we acquired complete AMR profiles related to seven classes of antibiotics. We also evaluated the performance of ONT-only assemblies. Most AMR determinants identified by ONT-only assemblies were the same as those identified by hybrid assemblies. Moreover, one of the nine assemblies indicated a potentially novel antimicrobial-related mutation located in mtrR which results in a frame-shift, premature stop codon, and truncated peptide. In addition, this is the first study using the MinION sequencer to obtain complete genome sequences of N. gonorrhoeae strains which are epidemic in China. This study shows that complete genome sequences and antimicrobial characteristics of N. gonorrhoeae can be obtained using the MinION sequencer in a simple and cost-effective manner, with hardly any knowledge of bioinformatics required. More importantly, this strategy provides us with a potential approach to discover new AMR determinants.

Polycyclic aromatic hydrocarbons (PAHs) in road dust (RD) and construction dust (CD) in PM2.5 were quantified in the samples collected in 20 Chinese cities. The PAHs profiles in urban PM2.5 fugitive dusts were determined and their potential health risks were evaluated. Seven geographical regions in China were identified as northwest China (NWC), the North China Plain (NCP), northeast China (NEC), central China (CC), south China (SC), southwest China (SWC), and east China (EC). The overall average concentrations of total quantified PAHs (ΣPAHs) were 23.2 ± 18.9 and 22.8 ± 29.6 μg·g−1 in RD and CD of PM2.5, indicating that severe PAHs pollution to urban fugitive dusts in China. The differences of ΣPAHs between RD and CD were minor in northern and central regions of China but much larger in southern and east regions. The ƩPAHs for RD displayed a pattern of “high in northern and low in southern”, and characterized by large abundance of high molecular weights (HMWs) PAHs, indicating that vehicle emission was the predominant pollution origin. Additionally, higher diagnostic ratios of fluoranthene/(fluoranthene + pyrene) in NCP, CC, and SWC suggest critical contributions of biomass burning and coal combustion for RD in these areas. In comparison, gasoline combustion was the major pollution source for CD PAHs in NWC, NCP, NEC, and CC, whereas industrial emissions such as cement production and iron smelting had strong impacts in the heavy industrial regions. The total benzo[a]pyrene (BaP) carcinogenic potency concentrations (BaPTEQ) for RD and CD both showed the lowest in SC (0.05 and 0.07, respectively) and the highest in NCP (10.99 and 7.67, respectively). The highest and lowest incremental life cancer risks (ILCR) were found in NCP and SC, coinciding with the spatial distributions of ambient PAHs levels. The total CD-related cancer risks for adults and children (~10−4) suggest high potential health risks in NCP, SWC, and NWC, whereas the evaluated values in EC and SC indicate virtual safety (≤10−6).

Background Population movement could extend multidrug-resistant tuberculosis (MDR-TB) transmission and complicate its global prevalence. We sought to identify the high-risk populations and geographic sites of MDR-TB transmission in Shenzhen, the most common destination for internal migrants in China. Methods We performed a population-based, retrospective study in patients diagnosed with MDR-TB in Shenzhen during 2013–2017. By defining genomic clusters with a threshold of 12–single-nucleotide polymorphism distance based on whole-genome sequencing of their clinical strains, the clustering rate was calculated to evaluate the level of recent transmission. Risk factors were identified by multivariable logistic regression. To further delineate the epidemiological links, we invited the genomic-clustered patients to an in-depth social network investigation. Results In total, 105 (25.2%) of the 417 enrolled patients with MDR-TB were grouped into 40 genome clusters, suggesting recent transmission of MDR strains. The adjusted risk for student to have a clustered strain was 4.05 (95% confidence interval, 1.06–17.0) times greater than other patients. The majority (70%, 28/40) of the genomic clusters involved patients who lived in different districts, with residences separated by an average of 8.76 kilometers. Other than household members, confirmed epidemiological links were also identified among classmates and workplace colleagues. Conclusions These findings demonstrate that local transmission of MDR-TB is a serious problem in Shenzhen. While most transmission occurred between people who lived distant from each other, there was clear evidence that transmission occurred in schools and workplaces, which should be included as targeted sites for active case finding. The average residential distance between genomic-clustered cases was more than 8 kilometers, while schools and workplaces, identified as sites of transmission in this study, deserve increased vigilance for targeted case finding of multidrug-resistant tuberculosis.

Saccharides are important constituents in atmospheric aerosols but studies in northwestern China are still very limited. Here, we have measured anhydrosugars (levoglucosan, mannosan and galactosan), primary sugars (glucose, fructose, sucrose and trehalose), and sugar alcohols (arabitol, mannitol, sorbitol and inositol) in ambient PM2.5 samples during summer and winter in Xi'an city, northwestern China. The abundance of total saccharides showed no clear seasonal variation, but apparent distinctions on the levels of the three categories and individual saccharide compounds were found. Primary sugars and particularly sucrose were dominant in summer. In contrast, levoglucosan was the predominant species in winter, contributing 60% of total saccharides. Source apportionment by positive matrix factorization revealed that airborne pollen was a major source of PM2.5 associated-saccharides in summer, accounting for 35% of total saccharides; while biomass burning activities contributed to 60% of the winter saccharides. Furthermore, an increasing trend of biomass/biofuel burning contribution to winter PM2.5 was observed in comparison with previous studies in Xi'an, suggesting a change in emission sources may be underway in northwestern China.

The growing antimicrobial resistance (AMR) in Neisseria gonorrhoeae is a serious global threat to gonococcal therapy. Molecular typing is an ideal tool to reveal the association between specific genotype and resistance phenotype that provides effective data for tracking the transmission of resistant clones of N. gonorrhoeae In our study, we aimed to describe the molecular epidemiology of AMR and the distribution of resistance-associated genotypes in Shenzhen during 2014-2018. In total, 909 isolates were collected from Shenzhen from 2014-2018. Two typing schemes, multilocus sequence typing (MLST) and N. gonorrhoeae Sequence Typing for Antimicrobial Resistance (NG-STAR), were performed for all isolates. The distribution of resistance-associated genotypes was described using goeBURST analysis combined with data of logistic regression. Among 909 isolates, ST8123, ST7363, ST1901, ST7365, and ST7360 were most the common MLST sequence types (STs), and ST348, ST2473, ST497, and ST199 were the most prevalent NG-STAR STs. The logistic regression analysis showed that NG-STARST497, MLSTST7365, and MLSTST7360 were typically associated with decreased susceptibility to ceftriaxone. Furthermore, the internationally spreading ESC-resistant clone MLSTST1901 has been prevalent at least in 2014 in Shenzhen and showed a significant increase during 2014-2018. Additionally, MLSTST7363 owns the potential to become the next internationally spreading ceftriaxone-resistant ST. In conclusions, we performed a comprehensive epidemiological study to explore the correlation between AMR and specific STs, which provided important data for future studies of the molecular epidemiology of AMR in N. gonorrhoeae Besides, these findings provide insight for adjusting surveillance strategies and therapy management in Shenzhen.

Solid fuel is a the most dominant energy source for household usages in developing countries. In this study, emission characteristics on organic carbon (OC), elemental carbon (EC) and fifty-two polycyclic aromatic hydrocarbons (PAHs) in gaseous and particulate phases from seven fuel-stove combinations were studied in a typical rural village in northwest China. For the PAHs, the highest gaseous and particulate phase emission factors (EFs) were both observed for bituminous coal with one-stage stoves, ranging from 459 ± 154 to 1.09 ± 0.36 × 10

The growing antimicrobial resistance (AMR) in Neisseria gonorrhoeae is a serious global threat to gonococcal therapy. Molecular typing is an ideal tool to reveal the association between specific genotypes and resistance phenotypes that provide effective data for tracking the transmission of resistant clones of N. gonorrhoeae. In our study, we aimed to describe the molecular epidemiology of AMR and the distribution of resistance-associated genotypes in Shenzhen, China, during 2014 to 2018. In total, 909 isolates were collected from Shenzhen from 2014 to 2018. Two typing schemes, multilocus sequence typing (MLST) and N. gonorrhoeae sequence typing for antimicrobial resistance (NG-STAR), were performed for all isolates. The distribution of resistance-associated genotypes was described using goeBURST analysis combined with logistic regression data. Among 909 isolates, sequence type 8123 (ST(8123)), ST(7363), ST(1901), ST(7365), and ST(7360) were the most common MLST sequence types, and ST(348), ST(2473), ST(497), and ST(199) were the most prevalent NG-STAR STs. Logistic regression analysis showed that NG-STAR(ST497), MLST(ST7365), and MLST(ST7360) were typically associated with decreased susceptibility to ceftriaxone. Furthermore, the internationally spreading extended-spectrum cephalosporin (ESC)-resistant clone MLST(ST1901) has been prevalent since at least 2014 in Shenzhen and showed a significant increase during 2014 to 2018. Additionally, MLST(ST7363) owns the potential to become the next internationally spreading ceftriaxone-resistant ST. In conclusion, we performed a comprehensive epidemiological study to explore the correlation between AMR and specific STs, which provided important data for future studies of the molecular epidemiology of AMR in N. gonorrhoeae. Besides, these findings provide insight for adjusting surveillance strategies and therapy management in Shenzhen.

Humic-like substances (HULIS) in PM

In this study, 3- or 4-h high time-resolved PM

Antimicrobial resistance in Neisseria gonorrhoeae persists as a major public health concern globally. We developed and evaluated a multiplex assay that relied on high-resolution melting (HRM) technology as a rapid, simple, and cost-effective method for simultaneously detecting and identifying different molecular markers associated with extended-spectrum cephalosporins (ESCs) and azithromycin (AZM) resistance in N. gonorrhoeae. Forty-eight well-characterized N. gonorrhoeae clinical isolates were selected for initial assay establishment. The multiplex HRM assays were able to accurately identify different nucleotide variations of the antimicrobial resistance determinants related to ESCs and AZM resistance. Specificity and cross-reactivity were assessed by testing 15 nongonococcal strains. Then, the assay was validated on 218 archived DNA specimens that had been sequenced using whole-genome sequencing technology. Compared with whole-genome sequencing, these assays had a sensitivity of 98.6%, with a specificity of 99.2%. For further validation of the assay's performance, a total of 338 samples (156 clinical isolates and 182 clinical specimens) were screened using the multiplex HRM assay. The results showed good concordance with the results of PCR sequencing. Given its rapidity (within 90 minutes), ease of performing, and low cost ($1.00 per sample), this method may be applied to large-scale epidemiologic programs for increasing surveillance of ESCs and AZM resistance in N. gonorrhoeae.

Ozone (O3) pollution has become an increasing concern in China since elevated surface O3 concentrations were observed in recent years. In this study, five provincial cities (Beijing, Shanghai, Guangzhou, Xi&rsquo, an, and Hefei) located in different regions of China were selected to study the spatiotemporal variations and affecting factors of O3 concentrations during 2014&ndash, 2015. Beijing, Shanghai, and Guangzhou had suffered more severe O3 pollution, yet Beijing had the highest number of days that exceeded the Chinese MDA8 (maximum daily 8 h average) standard of 160 &micro, g m&minus, 3. MDA8 O3 exhibited different seasonal patterns among the five cities. In Beijing and Xi&rsquo, an, MDA8 O3 showed the highest in summer and lowest in winter. Guangzhou also had the highest O3 concentration in summer, but had similar levels in other three seasons. The O3 levels were similarly high in Shanghai during spring, summer, and autumn, while in Hefei, O3 concentration peaked in autumn. No significant difference between weekend and weekday O3 levels was observed in all the five cities. The diurnal cycle reached a maximum in the afternoon and a minimum in the early morning, which was consistent in the five cities. Correlation analyses showed that the associations between O3 and the other five criteria air pollutants, as well as meteorological parameters, were substantially different among the five cities. Air mass cluster analyses during episodic days revealed that the short-distance transport of O3 and its precursors had a greater impact for high O3 pollution in the five cities. Overall, our results demonstrate that O3 pollution exhibited great divergence among different regions and thus region-oriented control measures are suggested to reduce O3 pollution in China.