44 research outputs found

    Impact of environmental comfort on urban vitality in small and medium-sized cities: A case study of Wuxi County in Chongqing, China

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    China's urbanization has exceeded 64% and a large number of small and medium-sized cities are the key development areas in the new stage. In urban planning, it is very important to reveal the influence of environmental comfort on urban vitality to improve the life quality of residents in these towns. Thus, the study investigated the impact of environmental comfort on urban vitality using ordinary least squares regression in Wuxi County. Environmental comfort was assessed through a comprehensive analysis of a built-up area and urban vitality was represented by vitality intensity. In addition, the influence pathways were identified and model validation was verified. The conclusions are as follows: (1) Environmental comfort and urban vitality are distributed spatially similarly, and both gradually decline from the center to the periphery. It is high in the east and low in the west, high in the south and low in the north. (2) Population density, POI mixing degree, building density, and road network density have significant positive effects on urban vitality. Population density has the greatest impact on urban vitality. Building height, building age, and river buffer have significant negative effects on urban vitality. (3) The impact of comprehensive environmental comfort on urban vitality is positive, and in terms of time, the order of impact is afternoon > morning > evening. Finally, a method for assessing the impact of environmental comfort on urban vitality was constructed, and the promoting effect of environmental comfort improvements on the vitality was verified. These findings will fill the gap between urban physical space and social needs in planning practices and provide reference to improve vitality for urban planning in small and medium-sized cities

    A Systematic RNAi Screen Reveals a Novel Role of a Spindle Assembly Checkpoint Protein BuGZ in Synaptic Transmission in C. elegans

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    Synaptic vesicles (SV) store various neurotransmitters that are released at the synapse. The molecular mechanisms of biogenesis, exocytosis, and endocytosis for SV, however, remain largely elusive. In this study, using Complex Object Parametric Analysis and Sorter (COPAS) to monitor the fluorescence of synapto-pHluorin (SpH), we performed a whole-genome RNAi screen in C. elegans to identify novel genetic modulators in SV cycling. One hundred seventy six genes that up-regulating SpH fluorescence and 96 genes that down-regulating SpH fluorescence were identified after multi-round screen. Among these genes, B0035.1 (bugz-1) encodes ortholog of mammalian C2H2 zinc-finger protein BuGZ/ZNF207, which is a spindle assembly checkpoint protein essential for mitosis in human cells. Combining electrophysiology, imaging and behavioral assays, we reveal that depletion of BuGZ-1 results in defects in locomotion. We further demonstrate that BuGZ-1 promotes SV recycling by regulating the expression levels of endocytosis-related genes such as rab11.1. Therefore, we have identified a bunch of potential genetic modulators in SV cycling, and revealed an unexpected role of BuGZ-1 in regulating synaptic transmission

    Identification of QTL underlying vitamin E contents in soybean seed among multiple environments

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    Vitamin E (VE) in soybean seed has value for foods, medicines, cosmetics, and animal husbandry. Selection for higher VE contents in seeds along with agronomic traits was an important goal for many soybean breeders. In order to map the loci controlling the VE content, F5-derived F6 recombinant inbred lines (RILs) were advanced through single-seed-descent (SSD) to generate a population including 144 RILs. The population was derived from a cross between ā€˜OAC Bayfieldā€™, a soybean cultivar with high VE content, and ā€˜Hefeng 25ā€™, a soybean cultivar with low VE content. A total of 107 polymorphic simple sequence repeat markers were used to construct a genetic linkage map. Seed VE contents were analyzed by high performance liquid chromatography for multiple years and locations (Harbin in 2007 and 2008, Hulan in 2008 and Suihua in 2008). Four QTL associated with Ī±-Toc (on four linkage groups, LGs), eight QTL associated with Ī³-Toc (on eight LGs), four QTL associated with Ī“-Toc (on four LGs) and five QTL associated with total VE (on four LGs) were identified. A major QTL was detected by marker Satt376 on linkage group C2 and associated with Ī±-Toc (0.0012Ā >Ā PĀ >Ā 0.0001, 5.0%Ā <Ā R2Ā <Ā 17.0%, 25.1Ā <Ā Ī±-TocĀ <Ā 30.1Ā Ī¼gĀ gāˆ’1), total VE (PĀ <Ā 0.0001, 7.0%Ā <Ā R2Ā <Ā 10.0%, 118.2Ā <Ā total VEĀ <Ā 478.3Ā Ī¼gĀ gāˆ’1). A second QTL detected by marker Satt286 on LG C2 was associated with Ī³-Toc (0.0003Ā >Ā PĀ >Ā 0.0001, 6.0%Ā <Ā R2Ā <Ā 13.0%, 141.5Ā <Ā Ī³-TocĀ <Ā 342.4Ā Ī¼gĀ gāˆ’1) and total VE (PĀ <Ā 0.0001, 2.0%Ā <Ā R2Ā <Ā 9.0%, 353.9Ā <Ā total VEĀ <Ā 404.0Ā Ī¼gĀ gāˆ’1). Another major QTL was detected by marker Satt266 on LG D1b that was associated with Ī±-Toc (0.0002Ā >Ā PĀ >Ā 0.0001, 4.0%Ā <Ā R2Ā <Ā 6.0%, 27.7Ā <Ā Ī±-TocĀ <Ā 43.7Ā Ī¼gĀ gāˆ’1) and Ī³-Toc (0.0032Ā >Ā PĀ >Ā 0.0001, 3.0%Ā <Ā R2Ā <Ā 10.0%, 69.7Ā <Ā Ī³-TocĀ <Ā 345.7Ā Ī¼gĀ gāˆ’1). Since beneficial alleles were all from ā€˜OAC Bayfieldā€™, it was concluded that these three QTL would have great potential value for marker assisted selection for high VE content

    Vegetation Activity Trend and Its Relationship with Climate Change in the Three Gorges Area, China

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    Based on SPOT/VGT NDVI time series images from 1999 to 2009 in the Three Gorges Area (TGA), we detected vegetation activity and trends using two methods, the Mann-Kendall and Slope tests. The relationships between vegetation activity trends and annual average temperature and annual total precipitation were analyzed using observational data in seven typical meteorological stations. Vegetation activity presents a distinctive uptrend during the study period, especially in Fengjie, Yunyang, Wushan, Wuxi, and Badong counties located in the midstream of the Three Gorges Reservoir. However, in the Chongqing major area (CMA) and its surrounding areas and Fuling, Yichang, and part of Wanzhou, vegetation activity shows a decreasing trend as a result of urban expansion. The NDVI has two fluctuation troughs in 2004 and 2006. The annual mean temperature presents a slight overall upward trend, but the annual total precipitation does not present a significant trend. And they almost have no significant correlations with the NDVI. Therefore, temperature and precipitation are not major influences on vegetation activity change. Instead, increasing vegetation cover benefits from a number of environment protection policies and management, and ecological construction is a major factor resulting in the upward trend. In addition, resettlement schemes mitigate the impact of human activity on vegetation activity

    A compact dual-band assembled quadrifilar helix antenna for LEO satellite communications

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    This paper presents a compact dual-band quadrifilar helix antenna suitable for satellite communications. The antenna consists of two quadrifilar helix antennas stacked vertically as a single unit. The upper quadrifilar helix antenna operates in the S-band, while the lower one operates in the L-band. The upper quadrifilar helix antenna adopts a self-rotating spiral structure and is fed by a slotted coaxial balun. The lower antenna is excited by a feed network with equal amplitudes and phase differences of 90Ā°. Simulation results show that the antenna has good circular polarization and wide beamwidth characteristics within the operating frequency band, with S11&lt;-12 dB at the S-band and S11&lt;-20 dB at the L-band. In addition, the gain is greater than 0 dBi in the Ā±60Ā° beamwidth range for both bands.<br/

    Assessing the Heat Vulnerability of Different Local Climate Zones in the Old Areas of a Chinese Megacity

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    Frequent and extreme heat waves have strongly influenced the sustainable development of cities and resulted in a higher level of mortality in residents. Using the Local Climate Zone (LCZ) classification scheme, combined with the factors of land surface temperature (LST), building age (BA), and housing price (HP), and the normalized values of which represent heat exposure, sensitivity, and adaptability, respectively, this paper investigates a practical method for assessing the heat vulnerability of different LCZ classes in the old areas of a Chinese megacity, taking the Yuzhong district of Chongqing city as a case study. The results reveal that the distribution of LCZ classes in this study area exhibits a typical circle-layer distribution pattern from the city center to the suburbs. Heavy industry areas are the most vulnerable, with the highest exposure to heat waves, the oldest building age and the lowest housing price. Compact class areas (compact high-rise, compact mid-rise and compact low-rise) are usually more vulnerable than open class areas (open high-rise, open mid-rise, and open low-rise) and low-rise buildings are always more susceptible to heat waves than mid-rise and high-rise buildings. The methods and findings can help us to better understand the comprehensive and space&#8211;time action rules of heat vulnerability, thereby inspiring scientific and rational urban planning strategies to mitigate or adapt to urban heat weaves towards the sustainable development of cities and society

    Evaluating Social Media Response to Urban Flood Disaster: Case Study on an East Asian City (Wuhan, China)

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    Social media is an important tool for disaster prevention and management. To reveal the public responses to disasters on social media in the context of East Asian culture, an urban flood disaster event that occurred in Wuhan City, China, in the summer of 2016 was selected as a case. Data were collected from Sina-Weibo, which is the earliest and most popular social media platform in China. We categorized a total of 17,047 messages into four types, analyzed the Pearson correlation between information dissemination and precipitation, and identified the important accounts and their messages in the social networks by visualized analysis. The results show that there is a one-day lag between participation and public response. Message dissemination has a steeply downward trend over time, that is, a long tail effect. Information disseminates quickly within two hours, and then dissemination declines after four hours, with opinion messages disseminating faster than other types of messages. Famous news organizations and several celebrities play a leading role in social networks. In general, the participation of Chinese netizens in disaster events is lower than that of people in Western countries, and social media is not yet used as a tool for disaster response

    Purification and characterization of a novel glycoprotein from Streptomyces sp ZX01

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    A novel glycoprotein GP-1 with antiviral activity against plant virus was isolated from the fermentation broth of the actinomycete Streptomyces sp. ZX01. MALDI-TOF-MS proved that molecular weight of GP-1 approximately was 8.5 kDa. GP-1 was a heat-sensitive glycoprotein with decreasing antiviral activity after treated from 80 degrees C to 100 degrees C for 30 min. GP-1 contained 40.23% carbohydrate with N-linked and O-linked glycan. FT-IR and NMR spectra proved that GP-1 contained protein and carbohydrate portions with alpha-D-(1,6)-glucose residues. Circular dichroism revealed that GP-1 was a glycoprotein with a large unordered content. Moreover, protein sequencing was predicted by using MALDI-TOF-MS and Mascot search. These results suggested that glycoprotein GP-1 could be used as a novel natural antiviral agent in agricultural industry. (C) 2015 Elsevier B.V. All rights reserved.</p
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