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以重庆市近郊中梁山槽谷为研究区,利用气象站和沉降仪获取2017年5月-2018年4月的大气无机氮、硫沉降数据和降水δ15N-NO3-、δ18O-NO3-和δ34S-SO42-、δ18O-SO42-数据,通过离子浓度比值、同位素值和气团后向轨迹探讨了研究区大气中氮、硫沉降变化特征及其来源。结果表明:(1)大气DIN总沉降量为19.99 kg/hm2,干、湿沉降量分别占11%和89%;大气S总沉降量为32.62 kg/hm2,干、湿沉降量分别占13%和87%。大气氮、硫湿沉降量与降水量均呈正相关(n=12,P < 0.01),氮、硫干湿沉降量具有明显的季节差异。(2)降水NH4+-N/NO3--N比值介于0.45-2.2之间,雨季(5-10月)NH4+-N/NO3--N>1,旱季(11-次年4月)NH4+-N/NO3--N<1,表明雨季氮主要来源于农业源,旱季来源于工业和交通源;降水NO3-/SO42-比值介于0.1-1.25之间,平均值为0.63,表明硫来源以固定污染源(燃煤)为主。(3)大气降水δ15N-NO3-、δ18O-NO3-值分别为-3.8‰-3.9‰(平均值为0.4‰±2.6‰)和58.7‰-98.7‰(平均值为76.1‰±14.3‰),夏季偏负,冬季偏正;降水δ34S-SO42-和δ18O-SO42-变化范围分别为1.3‰-3.2‰(平均值为2.3‰±1‰)和5.3‰-8.5‰(平均值为7.1‰±1.6‰),大气降水中NO3-和SO42-主要来源于当地的化石燃料燃烧,同时受到周边污染物的远距离传输影响。(4)气团后向轨迹表明影响研究区氮、硫干湿沉降来源的主要因素是东亚季风,北东-南西走向的川东平行岭谷大地貌格局加剧了季风的影响。 相似文献
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Xiaoguang Gu Jianan Zhang Yajuan Ran Hena Pan JinHong Jia Ying Zhao Xijuan Zhao Wendi Li Shasha Song Xiufeng Yu 《Cell death & disease》2021,12(4)
Circular RNAs have been reported to play significant roles in regulating pathophysiological processes while also guiding clinical diagnosis and treatment of hepatocellular carcinoma (HCC). However, only a few circRNAs have been identified thus far. Herein, we investigated the role of a specific closed-loop structure of hsa_circ_101555 that was generated by back-splicing of the host gene casein kinase 1 gamma 1 (CSNK1G1) in the development and proliferation of HCC. We investigated the expression of Hsa_circ_101555 in HCC and normal tissues using bioinformatics. The expression level of hsa_circ_101555 was further detected by fluorescence in situ hybridization and qRT-PCR in ten HCC patients. Transwell, migration, WST-1 assays, and colony formation assays were used to evaluate the role of hsa_circ_101555 in HCC development and proliferation. The regulatory mechanisms of hsa_circ_101555 in miR-145-5p and CDCA3 were determined by dual luciferase reporter assay. A mouse xenograft model was also used to determine the effect of hsa_circ_101555 on HCC growth in vivo. hsa_circ_101555 showed greater stability than the linear RNA; while in vitro and in vivo results demonstrated that hsa_circ_101555 silencing significantly suppressed cell proliferation, migration, and invasion of HCC cells. Rescue experiments further demonstrated that suppression of miR-145-5p significantly attenuated the biological effects of hsa_circ_101555 knockdown in HCC cells. We also identified a putative oncogene CDCA3 as a potential miR-145-5p target. Thus, our results demonstrated that hsa_circ_101555 might function as a competing endogenous RNA of miR-145-5p to upregulate CDCA3 expression in HCC. These findings suggest that hsa_circ_101555 may be a potential therapeutic target for patients with HCC.Subject terms: Liver cancer, Long non-coding RNAs 相似文献
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Jianan Wang Guorui Yang Jie Chen Yunpeng Liu Yuankun Wang Cheng‐Yen Lao Kai Xi Duowen Yang Christopher J. Harris Wei Yan Shujiang Ding Ramachandran Vasant Kumar 《Liver Transplantation》2019,9(38)
Lithium–sulfur batteries are appealing as high‐energy storage systems and hold great application prospects in wearable and portable electronics. However, severe shuttle effects, low sulfur conductivity, and especially poor electrode mechanical flexibility restrict sulfur utilization and loading for practical applications. Herein, high‐flux, flexible, electrospun fibrous membranes are developed, which succeed in integrating three functional units (cathode, interlayer, and separator) into an efficient composite. This structure helps to eliminate negative interface effects, and effectively drives synergistic boosts to polysulfide confinement, electron transfer, and lithium‐ion diffusion. It delivers a high initial capacity of 1501 mA h g?1 and a discharge capacity of 933 mA h g?1 after 400 cycles, with slow capacity attenuation (0.069% per cycle). Even under high sulfur loading (13.2 mg cm?2, electrolyte/sulfur ratio = 6 mL g?1) or in an alternative folded state, this three‐in‐one membrane still exhibits high areal capacity (11.4 mA h cm?2) and exceptional application performance (powering an array of over 30 light‐emitting diodes (LEDs)), highlighting its huge potential in high‐energy flexible devices. 相似文献
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Yuhui Xu Jianan Wu Sha Liao Zhaogang Sun 《Annals of clinical microbiology and antimicrobials》2017,16(1):67
Tuberculosis (TB) is considered as one of the most serious threats to public health in many parts of the world. The threat is even more severe in the developing countries where there is a lack of advanced medical amenities and contemporary anti-TB drugs. In such situations, dosage optimization of existing medication regimens seems to be the only viable option. Therapeutic drug monitoring study results suggest that high-dose treatment regimens can compensate the low serum concentration of anti-TB drugs and shorten the therapy duration. The article presents a critical review on the possible changes that occur in the host and the pathogen upon the administration of standard and high-dose regimens. Some of the most common factors that are responsible for low anti-TB drug concentrations in the serum are differences in hosts’ body weight, metabolic processing of the drug, malabsorption and/or drug–drug interaction. Furthermore, failure to reach the cavitary pulmonary and extrapulmonary tissues also contributes to the therapeutic inefficiency of the drugs. In such conditions, administration of higher doses can help in compensating the pathogenic outcomes of enhancement of the pathogen’s physical barriers, efflux pumps and genetic mutations. The present article also presents a summary of the recorded treatment outcomes of clinical trials that were conducted to test the efficacy of administration of high dose of anti-tuberculosis drugs. This review will help physicians across the globe to understand the underlying pathophysiological changes (including side effects) that dictate the clinical outcomes in patients administered with standard and/or high dose anti-TB drugs. 相似文献
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