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391.
392.
Yuguang Niu Chengyong Xie Zhenhua Du Jifeng Zeng Hongxia Chen Liang Jin Qing Zhang Huiying Yu Yahui Wang Jie Ping Chenning Yang Xinyi Liu Yuanfeng Li Gangqiao Zhou 《Journal of cellular and molecular medicine》2021,25(1):411-420
Noise-induced hearing loss (NIHL) seriously affects the life quality of humans and causes huge economic losses to society. To identify novel genetic loci involved in NIHL, we conducted a genome-wide association study (GWAS) for this symptom in Chinese populations. GWAS scan was performed in 89 NIHL subjects (cases) and 209 subjects with normal hearing who have been exposed to a similar noise environment (controls), followed by a replication study consisting of 53 cases and 360 controls. We identified that four candidate pathways were nominally significantly associated with NIHL, including the Erbb, Wnt, hedgehog and intraflagellar transport pathways. In addition, two novel index single-nucleotide polymorphisms, rs35075890 in the intron of AUTS2 gene at 7q11.22 (combined P = 1.3 × 10−6) and rs10081191 in the intron of PTPRN2 gene at 7q36.3 (combined P = 2.1 × 10−6), were significantly associated with NIHL. Furthermore, the expression quantitative trait loci analyses revealed that in brain tissues, the genotypes of rs35075890 are significantly associated with the expression levels of AUTS2, and the genotypes of rs10081191 are significantly associated with the expressions of PTPRN2 and WDR60. In conclusion, our findings highlight two novel loci at 7q11.22 and 7q36.3 conferring susceptibility to NIHL. 相似文献
393.
为揭示亚热带地区杉木(Cunninghamialanceolata)对干旱的响应机制,在福建三明森林生态系统国家野外科学观测研究站,对隔离降水环境下杉木幼树细根生理特征进行研究。结果表明,隔离降水处理的土壤湿度显著下降(P<0.05),但杉木细根超氧阴离子自由基、丙二醛含量变化不显著(P>0.05),表明其细根保持着低水平的膜脂氧化损伤;脯氨酸和谷胱甘肽含量较对照显著增加(P<0.05),并且过氧化氢含量也显著增加(P<0.05),意味着杉木受到一定程度的干旱胁迫并且进行自我调节;长期降水隔离导致的过氧化氢积累一定程度上促使谷胱甘肽显著提高,二者呈极显著正相关(P<0.01);内源激素中细胞分裂素、吲哚乙酸含量显著下降,与杉木生长调控未表现出明显相关性;超氧化物歧化酶活性较对照显著下降21.5%,过氧化物酶活性较对照显著提高16.7%,但抗氧化酶系统对杉木细根的水分缺失适应调控无显著影响。因此,50%降水减少条件下杉木能通过其细根的渗透物质和内源激素等非酶促物质进行综合调节,以有效适应土壤湿度的显著降低。 相似文献
394.
Patrick M. Ewing Xinyi Tu Bryan C. Runck Alison Nord Regis Chikowo Sieglinde S. Snapp 《Global Change Biology》2023,29(6):1471-1483
Increasing soil organic carbon (SOC) stocks is increasingly targeted as a key strategy in climate change mitigation and improved ecosystem resiliency. Agricultural land, a dominant global land use, provides substantial challenges and opportunities for global carbon sequestration. Despite this, global estimates of soil carbon sequestration potential often exclude agricultural land and estimates are coarse for regions in the Global South. To address these discrepancies and improve estimates, we develop a hybrid, data-augmented database approach to better estimate the magnitude of SOC sequestration potential of agricultural soils. With high-resolution (30 m) soil maps of Africa developed by the International Soils Database (iSDA) and Malawi as a case study, we create a national adjustment using site-specific soil data retrieved from 1160 agricultural fields. We use a benchmark approach to estimate the amount of SOC Malawian agricultural soils can sequester, accounting for edaphic and climatic conditions, and calculate the resulting carbon gap. Field measurements of SOC stocks and sequestration potentials were consistently larger than iSDA predictions, with an average carbon gap of 4.42 ± 0.23 Mg C ha−1 to a depth of 20 cm, with some areas exceeding 10 Mg C ha−1. Augmenting iSDA predictions with field data also improved sensitivity to identify areas with high SOC sequestration potential by 6%—areas that may benefit from improved management practices. Overall, we estimate that 6.8 million ha of surface soil suitable for agriculture in Malawi has the potential to store 274 ± 14 Tg SOC. Our approach illustrates how ground truthing efforts remain essential to reduce errors in continent-wide soil carbon predictions for local and regional use. This work begins efforts needed across regions to develop soil carbon benchmarks that inform policies and identify high-impact areas in the effort to increase SOC globally. 相似文献
395.
Cedric Peirs Sean-Paul G. Williams Xinyi Zhao Cynthia M. Arokiaraj David W. Ferreira Myung-chul Noh Kelly M. Smith Priyabrata Halder Kelly A. Corrigan Jeremy Y. Gedeon Suh Jin Lee Graziana Gatto David Chi Sarah E. Ross Martyn Goulding Rebecca P. Seal 《Neuron》2021,109(1):73-90.e7
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396.
Qingzhou Meng Xinjie Wang Yanqun Wang Lu Dang Xinyi Liu Xiaodong Ma Tian Chi Xian Wang Qin Zhao Guang Yang Ming Liu Xingxu Huang Peixiang Ma 《Biotechnology journal》2021,16(6):2100040
Detection of pathogens with single-nucleotide variations is indispensable for the disease tracing, but remains technically challenging. The D614G mutation in the SARS-CoV-2 spike protein is known to markedly enhance viral infectivity but is difficult to detect. Here, we report an effective approach called “synthetic mismatch integrated crRNA guided Cas12a detection” (symRNA-Cas12a) to detect the D614 and G614 variants effectively. Using this method, we systemically screened a pool of crRNAs that contain all the possible nucleotide substitutions covering the -2 to +2 positions around the mutation and identify one crRNA that can efficiently increase the detection specificity by 13-fold over the ancestral crRNA. With this selected crRNA, the symRNA-Cas12a assay can detect as low as 10 copies of synthetic mutant RNA and the results are confirmed to be accurate by Sanger sequencing. Overall, we have developed the symRNA-Cas12a method to specifically, sensitively and rapidly detect the SARS-CoV-2 D614G mutation. 相似文献
397.
In aquaculture, high-density seaweed farming brings higher economic benefits but also increases outbreaks of diatom felt. The effective control of diatom felt in high-density seaweed farming has always been a research hotspot.
This study selected two potential allelochemicals 2-hydroxycinnamic acid and quinic acid to explore their effects
on a diatom Nitzschia closterium and an economic seaweed Monostroma nitidum. The results showed that
2-hydroxycinnamic acid had better inhibitory effects than quinic acid on the growth, pigment content and photosynthetic efficiency of N. closterium. Their half-maximal inhibitory concentrations at 120 h (IC50–120 h) were
0.9000 and 1.278 mM, respectively. Additionally, these allelochemicals had limited inhibitory effects on the
growth, pigment content and photosynthetic efficiency of M. nitidum before 24 h. To further explore the allelopathic effect of these chemicals, this study focused on the photosystem II energy fluxes of N. closterium. It was
found that 3 mM 2-hydroxycinnamic acid could destroy the whole photosynthetic system by devastating the PSII
reaction centre (RC) before 24 h; however, the same concentration of quinic acid could only down-regulate the
electron transport efficiency by changing the effective antenna size of an active RC and downregulating the PSII
reaction centre density. These experimental results are expected to provide a new strategy to control diatom felt
blooms on the high-density seaweed farming areas. 相似文献
398.
Feihang Yan Jiebin Fang Wanjing Ding Xinyi Tang Xiaoming Chen Prof. Dr. Zhongjun Ma Dr. Jinhui Wang 《化学与生物多样性》2023,20(9):e202301017
Nine new compounds, including streptothiomycin A−E ( 1 – 5 ), two cyclopentenones ( 6 , 7 ), one α-pyrone ( 8 ), wailupemycin Q ( 20 ), along with sixteen known compounds were identified from a rhizosphere strain Streptomyces sp. DS-27 derived from the marine cordgrass Spartina alterniflora under two different culture conditions. All of the structures were elucidated by extensive analysis of 1D/2D NMR and HR-ESI-MS data. The absolute configurations were determined by NOESY analysis, ECD, specific rotation and GIAO NMR calculations, and DP4+ probability analysis. Bioactivity investigation showed that compounds 5 and 7 exhibited significant inhibitory effects on LPS-induced NO production in a dose-dependent manner, which indicates their anti-inflammatory potential. 相似文献
399.
In this work, we conceive and demonstrate the magneto-electric double Fano resonances of a hetero-cavity composed of Si disk and Au split ring, where Si disk can provide additional magnetic responses besides electric responses. The interference between electric and magnetic responses in proposed hetero-cavity gives rise to magneto-electric double Fano resonances with magnetic and electric near-field enhancements. Dipole radiative enhancement is used to analyze magnetic and electric responses of hetero-cavity and the spectral features of hetero-cavity can be used to quantitatively characterize by coupled oscillator model. And the spectral tunability of magneto-electric double Fano resonances is investigated, highlighting a potential for applications in low-loss sensing and nanophotonic devices. 相似文献
400.
本文对多项式微分方程无穷远奇点的性态进行了研究,当无穷远奇点是初等奇点时,给出了用系数判定其稳定性态的方法,并用此方法对一类生态系统无穷远奇点的性态进行了讨论,从中可见,我们的方法优于现有方法。 相似文献