319 research outputs found
Novel approach to investigate decays via
To avoid the impact from the background events directly from
annihilations or decays, we propose a novel approach to investigate
decays, in particular for its rare or forbidden decays, by using
produced in decays at the
charm factories. Based on the MC studies of a few typical decays,
, , , as well as
, the sensitivities could be obviously improved by taking
advantage of the extra constraint of . Using one trillion
events accumulated at the Super -Charm facility, the precision on the
investigation of decays could be improved significantly and the
observation of the rare decay is even accessable.Comment: 7 pages, 6 figure
Determining the macroinvertebrate community indicators and relevant environmental predictors of the Hun-Tai River Basin (Northeast China): A study based on community patterning
[EN] It is essential to understand the patterning of biota and environmental influencing factors for proper rehabilitation and management at the river basin scale. The Hun-Tai River Basin was extensively sampled four times for macroinvertebrate community and environmental variables during one year. Self-Organizing Maps (SOMs) were used to reveal the aggregation patterns of the 355 samples. Three community types (i.e., clusters) were found (at the family level) based on the community composition, which showed a clearly gradient by combining them with the representative environmental variables: minimally impacted source area, intermediately anthropogenic impacted sites, and highly anthropogenic impacted downstream area, respectively. This gradient was corroborated by the decreasing trends in density and diversity of macroinvertebrates. Distance from source, total phosphorus and water temperature were identified as the most important variables that distinguished the delineated communities. In addition, the sampling season, substrate type, pH and the percentage of grassland were also identified as relevant variables. These results demonstrated that macroinvertebrates communities are structured in a hierarchical manner where geographic and water quality prevail over temporal (season) and habitat (substrate type) features at the basin scale. In addition, it implied that the local-scale environment variables affected macroinvertebrates under the longitudinal gradient of the geographical and anthropogenic pressure. More than one family was identified as the indicator for each type of community. Abundance contributed significantly for distinguishing the indicators, while Baetidae with higher density indicated minimally and intermediately impacted area and lower density indicated highly impacted area. Therefore, we suggested the use of abundance data in community patterning and classification, especially in the identification of the indicator taxa. (C) 2018 Elsevier B.V. All rights reserved.This work was supported by the National Natural Science Foundation of China (51779275, 41501204, 51479219) and the IWHR Research & Development Support Program (WE0145B532017).Zhang, M.; Muñoz Mas, R.; Martinez-Capel, F.; Qu, X.; Zhang, H.; Peng, W.; Liu, X. (2018). Determining the macroinvertebrate community indicators and relevant environmental predictors of the Hun-Tai River Basin (Northeast China): A study based on community patterning. The Science of The Total Environment. 634:749-759. https://doi.org/10.1016/j.scitotenv.2018.04.021S74975963
Design and optimization of dispersion-flattened microarray-core fiber with ultralow loss for terahertz transmission
The paper establishes a late-model of microarray-core based polymer optical fiber with flattened dispersion and ultra-low losses. Its transmission properties are calculated by virtue of the beam propagation approach. From the simulation results, it finds that the modelled fiber has a near-zero dispersion property of 0.29 ± 0.16 ps/THz/cm in a frequency area of 1.05 THz to 1.78 THz, a high birefringence of 1.6 × 10-3, an ultra-low confinement loss of 3.78 × 10-10 dB/m, an effective mode field zone of 4.6 × 105 μm2, and a nonlinear coefficient of 1.2 km-1·W−1. With these good properties, the modelled fiber could be applied for ethanol detection and polarization maintaining THz applications
Relative Quantification of Protein-Protein Interactions Using a Dual Luciferase Reporter Pull-Down Assay System
The identification and quantitative analysis of protein-protein interactions are essential to the functional characterization of proteins in the post-proteomics era. The methods currently available are generally time-consuming, technically complicated, insensitive and/or semi-quantitative. The lack of simple, sensitive approaches to precisely quantify protein-protein interactions still prevents our understanding of the functions of many proteins. Here, we develop a novel dual luciferase reporter pull-down assay by combining a biotinylated Firefly luciferase pull-down assay with a dual luciferase reporter assay. The biotinylated Firefly luciferase-tagged protein enables rapid and efficient isolation of a putative Renilla luciferase-tagged binding protein from a relatively small amount of sample. Both of these proteins can be quantitatively detected using the dual luciferase reporter assay system. Protein-protein interactions, including Fos-Jun located in the nucleus; MAVS-TRAF3 in cytoplasm; inducible IRF3 dimerization; viral protein-regulated interactions, such as MAVS-MAVS and MAVS-TRAF3; IRF3 dimerization; and protein interaction domain mapping, are studied using this novel assay system. Herein, we demonstrate that this dual luciferase reporter pull-down assay enables the quantification of the relative amounts of interacting proteins that bind to streptavidin-coupled beads for protein purification. This study provides a simple, rapid, sensitive, and efficient approach to identify and quantify relative protein-protein interactions. Importantly, the dual luciferase reporter pull-down method will facilitate the functional determination of proteins
Meta-analysis of relationship between short-term ozone exposure and population mortality in China
BackgroundIn recent years, our country's atmospheric particulate matter pollution has improved significantly, while ozone (O3) pollution has become increasingly serious. As a secondary pollutant, O3 is closely related to human health. ObjectiveTo study the effect of short-term exposure to ozone in ambient air on population mortality in China. MethodsA computer search with key words of "ozone or O3", "death", and "time series" in Chinese or "ozone", "mortality", and "China" in English was performed in Web of Science, PubMed, China National Knowledge Infrastructure, Wanfang, and VIP databases to find literature on effects of short-term ozone exposure on population mortality covering a time period from January 1, 1990 to December 31, 2021. According to a set of inclusion and exclusion criteria developed for this study, literaturescreening, quality evaluation, andrelevant data extraction were carried out. Finally, R 4.1.2 software was used to perform meta-analysis to estimate target effect sizes. ResultsA total of 978 articles were retrieved. According to the inclusion and exclusion criteria, 18 articles were finally included, including 39 effect size estimates. The results showed that every 10 μɡ·m−3 increase in ambient ozone concentration was associated with an increase of 0.45% (95%CI: 0.39%-0.51%), 0.50% (95%CI: 0.33%-0.68%), and 0.60% (95%CI: 0.48%-0.72%) in total, respiratory, and cardiovascular disease mortalities , respectively. The results of subgroup analysis by age, sex, and season showed that when ozone concentration increased 10 μɡ·m−3, an increase of 0.34% (95%CI: 0.17%-0.51%) in mortality was observed in the ≥ 65-year-old population, higher than 0.09% (95%CI: −0.21%-0.39%) increase in the <65-year-old population; the mortality increase in females [0.44% (95%CI: 0.30%-0.58%)] was greater than that in males [0.35% (95%CI: 0.22%-0.48%)]; compared with the warm season [0.29% (95%CI: 0.16%-0.42%)], mortality increase was higher in the cold season [1.03% (95%CI: 0.71%-1.35%)]. ConclusionAmbient ozone is an important factor affecting population mortality. The elderly and women ≥ 65 years old in China are more sensitive to ozone, and the impact of ozone exposure on population mortality is greater in cold season
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