43 research outputs found

    Characterization of Sucrose transporter alleles and their association with seed yield-related traits in Brassica napus L

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    <p>Abstract</p> <p>Background</p> <p>Sucrose is the primary photosynthesis product and the principal translocating form within higher plants. <it>Sucrose transporters </it>(<it>SUC/SUT</it>) play a critical role in phloem loading and unloading. Photoassimilate transport is a major limiting factor for seed yield. Our previous research demonstrated that <it>SUT </it>co-localizes with yield-related quantitative trait loci. This paper reports the isolation of <it>BnA7.SUT1 </it>alleles and their promoters and their association with yield-related traits.</p> <p>Results</p> <p>Two novel <it>BnA7.SUT1 </it>genes were isolated from <it>B. napus </it>lines 'Eagle' and 'S-1300' and designated as <it>BnA7.SUT1.a </it>and <it>BnA7.SUT1.b</it>, respectively. The BnA7.SUT1 protein exhibited typical SUT features and showed high amino acid homology with related species. Promoters of <it>BnA7.SUT1.a </it>and <it>BnA7.SUT1.b </it>were also isolated and classified as <it>pBnA7.SUT1.a </it>and <it>pBnA7.SUT1.b</it>, respectively. Four dominant sequence-characterized amplified region markers were developed to distinguish <it>BnA7.SUT1.a </it>and <it>BnA7.SUT1.b</it>. The two genes were estimated as alleles with two segregating populations (F<sub>2 </sub>and BC<sub>1</sub>) obtained by crossing '3715'×'3769'. <it>BnA7.SUT1 </it>was mapped to the A7 linkage group of the TN doubled haploid population. <it>In silico </it>analysis of 55 segmental <it>BnA7.SUT1 </it>alleles resulted three <it>BnA7.SUT1 </it>clusters: <it>pBnA7.SUT1.a- BnA7.SUT1.a </it>(type I), <it>pBnA7.SUT1.b- BnA7.SUT1.a </it>(type II), and <it>pBnA7.SUT1.b- BnA7.SUT1.b </it>(type III). Association analysis with a diverse panel of 55 rapeseed lines identified single nucleotide polymorphisms (SNPs) in promoter and coding domain sequences of <it>BnA7.SUT1 </it>that were significantly associated with one of three yield-related traits: number of effective first branches (EFB), siliques per plant (SP), and seed weight (n = 1000) (TSW) across all four environments examined. SNPs at other <it>BnA7.SUT1 </it>sites were also significantly associated with at least one of six yield-related traits: EFB, SP, number of seeds per silique, seed yield per plant, block yield, and TSW. Expression levels varied over various tissue/organs at the seed-filling stage, and <it>BnA7.SUT1 </it>expression positively correlated with EFB and TSW.</p> <p>Conclusions</p> <p>Sequence, mapping, association, and expression analyses collectively showed significant diversity between the two <it>BnA7.SUT1 </it>alleles, which control some of the phenotypic variation for branch number and seed weight in <it>B. napus </it>consistent with expression levels. The associations between allelic variation and yield-related traits may facilitate selection of better genotypes in breeding.</p

    A new critical exposition of the controversy between H.L.A. Hart and R.M. Dworkin

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    textabstractObjective: To adapt the Appropriateness Evaluation Protocol (AEP) to the specific settings of health care in China and to validate the Chinese version AEP (C-AEP). Methods: Forward and backward translations were carried out to the original criteria. Twenty experts participated in the consultancy to form a preliminary version of the C-AEP. To ensure applicability, tests of reliability and validity were performed on 350 admissions and 3,226 hospital days of acute myocardial infraction patients and total hip replacement patients in two tertiary hospitals by two C-AEP reviewers and two physician reviewers. Overall agreement, specific agreement, and Cohen's Kappa were calculated to compare the concordance of decisions between pairs of reviewers to test inter-rater reliability and convergent validity. The use of "overrides" and opinions of experts were recorded as measurements of content validity. Face validity was tested through collecting perspectives of nonprofessionals. Sensitivity, specificity, and predictive values were also reported. Results: There are 14 admission and 24 days of care criteria in the initial version of C-AEP. Kappa coefficients indicate substantial agreement between reviewers: with regard to inter-rater reliability, Kappa (κ) coefficients are 0.746 (95% confidence interval [CI] 0.644-0.834) and 0.743 (95% CI 0.698-0.767) of admission and hospital days, respectively; for convergent validity, the κ statistics are 0.678 (95% CI 0.567-0.778) and 0.691 (95% CI 0.644-0.717), respectively. Overrides account for less than 2% of all judgments. Content validity and face validity were confirmed by experts and nonprofessionals, respectively. According to the C-AEP reviewers, 18.3% of admissions and 28.5%of inpatient days were deemed inappropriate. Conclusions: The C-AEP is a reliable and valid screening tool in China's tertiary hospitals. The prevalence of inappropriateness is substantial in our research. To reduce inappropriate utilization, further investigation is needed to elucidate the reasons and risk factors for this inappropriateness. Copyright

    Current Status and Variation since 1964 of the Glaciers around the Ebi Lake Basin in the Warming Climate

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    This work analyzed the spatial and temporal variations of the glaciers in the Ebi Lake basin during the period 1964 to 2019, based on the 1st and 2nd Chinese Glacier Inventories (CGI) and remote sensing data; this is believed to be the first long-term comprehensive remote sensing investigation on the glacier change in this area, and it also diagnosed the response of the glaciers to the warming climate by analyzing digital elevation modeling and meteorology. The results show that there are 988 glaciers in total in the basin, with a total area of 560 km2 and average area of 0.57 km2 for a single glacier. The area and number of the glaciers oriented north and northeast are 205 km2 (327 glaciers) and 180 km2 (265 glaciers), respectively. The glaciers are categorized into eight classes as per their area, which are less than 0.1, 0.1–0.5, 0.5–1.0, 1.0–2.0, 2.0–5.0, 5.0–10.0, 10.0–20.0, and greater than 20.0 km2, respectively. The smaller glaciers between 0.1 km2 and 10.0 km2 account for 509 km2 or 91% in total area, and, in particular, the glaciers smaller than 0.5 km2 account for 74% in the total number. The glacial area is concentrated at 3500–4000 m in altitude (512 km2 or 91.4% in total). The number of glaciers in the basin decreased by 10.5% or 116, and their area decreased by 263.29 km2 (−4.79 km2 a−1) or 32% (−0.58% a−1) from 1964 to 2019; the glaciers with an area between 2.0 km2 and 5.0 km2 decreased by the largest, −82.60 km2 or −40.67% in the total area at −1.50 km2 a−1 or −0.74% a−1), and the largest decrease in number (i.e., 126 glaciers) occurs between 0.1 km2 and 0.5 km2. The total ice storage in the basin decreased by 97.84–153.22 km3 from 1964 to 2019, equivalent to 88.06–137.90 km3 water (taking 0.9 g cm−3 as ice mass density). The temperature increase rate in the basin was +0.37 °C decade−1, while the precipitation was +13.61 mm decade−1 during the last fifty-five years. This analysis shows that the increase in precipitation in the basin was not sufficient to compensate the mass loss of glaciers caused by the warming during the same period. The increase in temperature was the dominant factor exceeding precipitation mass supply for ruling the retreat of the glaciers in the entire basin

    Current Status and Variation since 1964 of the Glaciers around the Ebi Lake Basin in the Warming Climate

    No full text
    This work analyzed the spatial and temporal variations of the glaciers in the Ebi Lake basin during the period 1964 to 2019, based on the 1st and 2nd Chinese Glacier Inventories (CGI) and remote sensing data; this is believed to be the first long-term comprehensive remote sensing investigation on the glacier change in this area, and it also diagnosed the response of the glaciers to the warming climate by analyzing digital elevation modeling and meteorology. The results show that there are 988 glaciers in total in the basin, with a total area of 560 km2 and average area of 0.57 km2 for a single glacier. The area and number of the glaciers oriented north and northeast are 205 km2 (327 glaciers) and 180 km2 (265 glaciers), respectively. The glaciers are categorized into eight classes as per their area, which are less than 0.1, 0.1–0.5, 0.5–1.0, 1.0–2.0, 2.0–5.0, 5.0–10.0, 10.0–20.0, and greater than 20.0 km2, respectively. The smaller glaciers between 0.1 km2 and 10.0 km2 account for 509 km2 or 91% in total area, and, in particular, the glaciers smaller than 0.5 km2 account for 74% in the total number. The glacial area is concentrated at 3500–4000 m in altitude (512 km2 or 91.4% in total). The number of glaciers in the basin decreased by 10.5% or 116, and their area decreased by 263.29 km2 (−4.79 km2 a−1) or 32% (−0.58% a−1) from 1964 to 2019; the glaciers with an area between 2.0 km2 and 5.0 km2 decreased by the largest, −82.60 km2 or −40.67% in the total area at −1.50 km2 a−1 or −0.74% a−1), and the largest decrease in number (i.e., 126 glaciers) occurs between 0.1 km2 and 0.5 km2. The total ice storage in the basin decreased by 97.84–153.22 km3 from 1964 to 2019, equivalent to 88.06–137.90 km3 water (taking 0.9 g cm−3 as ice mass density). The temperature increase rate in the basin was +0.37 °C decade−1, while the precipitation was +13.61 mm decade−1 during the last fifty-five years. This analysis shows that the increase in precipitation in the basin was not sufficient to compensate the mass loss of glaciers caused by the warming during the same period. The increase in temperature was the dominant factor exceeding precipitation mass supply for ruling the retreat of the glaciers in the entire basin

    Uncovering the Deviation of Farmers’ Green Manure Planting Willingness and Behavior

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    Planting green manure is an effective way to improve the agricultural environment and the quality of cultivated land in China. However, deviation from green manure planting willingness and behavior (DWB) becomes a serious obstacle to the promotion of green manure planting technology. For economic farmers, whether to plant green manure is a rational choice made after weighing up family endowments. In addition, ecological cognition plays a moderating role in the “willingness-behavior” transformation process of farmers’ green manure planting on the basis of family endowments. We selected four counties in which to conduct a questionnaire survey in Gansu and carried out interviews with 375 farmers. Based on the survey data, our study identified determinants that influence farmers’ DWB and examined the moderating effect of ecological cognition. In our paper, results show that the probability of farmers’ DWB is 41.87%. Farmers’ DWB is not only negatively affected by social network information and ecological compensation (eco-compensation) and positively influenced by the scale of cultivated land, but also restricted by human capital endowment characteristics such as age and education. In addition, ecological cognition played a significant moderating effect on farmers’ DWB. Farmers with high ecological cognition were more aware and capable of promoting green manure planting intentions into practice. Furthermore, different groups of farmers had different characteristics of DWB. The findings are useful and helpful in better understand the influencing factors of farmers’ DWB for policy makers and managers and can provide some effective support for policies designed to encourage farmers to adopt more sustainable green manure

    Design, Optimization and Improvement of FBG Flexible Sensor for Slope Displacement Profiles Measurement

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    The accurate measurement of slope displacement profiles using a fiber Bragg grating flexible sensor is limited due to the influence of accumulative measurement errors. The measurement errors vary with the deformation forms of the sensor, which dramatically affects the measurement accuracy of the slope displacement profiles. To tackle the limitations and improve the measurement precision of displacement profiles, a segmental correction method based on strain increments clustering was proposed. A K-means clustering algorithm was used to automatically identify the deformation segments of a flexible sensor with different bending shapes. Then, the particle swarm optimization method was adopted to determine the correction coefficients corresponding to different deformation segments. Both finite element simulations and experiments were performed to validate the superiority of the proposed method. The experimental results indicated that the mean absolute errors (MAEs) percentages of the reconstructed displacements using the proposed method for six different bending shapes were 1.87%, 5.28%, 6.98%, 7.62%, 4.16% and 8.31%, respectively, which had improved the accuracy by 26.83%, 18.94%, 29.49%, 26.35%, 7.39%, and 19.65%, respectively. Therefore, it was confirmed that the proposed correction method was competent for effectively mitigating the measurement errors and improving the measurement accuracy of slope displacement profiles, and it presented a vital significance and application promotion value

    Measuring the Spatial Allocation Rationality of Service Facilities of Residential Areas Based on Internet Map and Location-Based Service Data

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    The spatial allocation rationality of the service facilities of residential areas, which is affected by the scope of the population and the capacity of service facilities, is meaningful for harmonious urban development. The growth of the internet, especially Internet map and location-based service (LBS) data, provides micro-scale knowledge about residential areas. The purpose is to characterize the spatial allocation rationality of the service facilities of residential areas from Internet map and LBS data. An Internet map provides exact geographical data (e.g., points of interests (POI)) and stronger route planning analysis capability through an application programming interface (API) (e.g., route planning API). Meanwhile, LBS data collected from mobile equipment afford detailed population distribution values. Firstly, we defined the category system of service facilities and calculated the available service facilities capacity of residential areas (ASFC-RA) through a scrappy algorithm integrated with the modified cumulative opportunity measure model. Secondly, we used Thiessen polygon spatial subdivision to gain the population distribution capacity of residential areas (PDC-RA) from Tencent LBS data at the representative moment. Thirdly, we measured the spatial allocation rationality of service facilities of residential areas (SARSF-RA) by combining ASFC-RA and PDC-RA. In this case, a trial strip census, consisting of serval urban residential areas from Wuxi City, Jiangsu Province, is selected as research area. Residential areas have been grouped within several ranges according to their SARSF-RA values. Different residential areas belong to different groups, even if they are spatially contiguous. Spatial locations and other investigation information coordinate with these differences. Those results show that the method that we proposed can express the micro-spatial allocation rationality of different residential areas dramatically, which provide a new data lens for various researchers and applications, such as urban residential areas planning and service facilities allocation

    Farmers’ Adoption Preferences for Sustainable Agriculture Practices in Northwest China

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    In the highest soil erosion regions of arid and semiarid northwest China, water resource deficits and farmland misuse have further exacerbated soil degradation. Therefore, understanding how farmers in diverse agroclimatic zones perceive and respond to different conservation practices is important to the implementation of sustainable agriculture practices (SAPs). To this end, this study uses a best&ndash;worst scaling approach to examine the adoption preferences for nine SAPs among grain and cash crop farmers and investigates the influence of farm and climatic characteristics on adoption preferences based on a face to face survey of 554 households in Gansu province, which is classified as an arid and semiarid area in northwest China. Both grain and cash crop farmers had stronger preferences for the practices of using organic instead of chemical fertilizers and of improving irrigation practices. In addition, while cash crop farmers also had strong preferences for cover crop-related practices, they preferred long-term fallows least. Household income, livestock, and precipitation influence the potential perceived importance of SAPs. The different perceived importance of these practices suggests new possible combinations or packages for a sustainable agriculture program during the cropping structure adjustment in Gansu

    Optimizing Somatic Embryogenesis Initiation, Maturation and Preculturing for Cryopreservation in Picea pungens

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    Picea pungens (Engelm.), known for its blue-green needles, has become a likable ornamental species in northeast China since 2000. Nonetheless, a lack of propagation methods that can maintain genetic fidelity and develop seedlings at a large scale prevents the further expansion of the species. Somatic embryogenesis (SE), paired with cryopreservation technologies, may provide a valid alternative. Picea pungens SE is not new, but its practical application has been limited due to low efficiencies in SE initiation and maturation as well as a lack of effective cryopreservation technology. In this study, experiments were carried out to overcome the limitations by modifying culture media. For initiation, the efficiency was enhanced by adjusting concentrations of 2.4-dichlorophenoxy acetic acid (2,4-D), 6-benzyl amino&ndash;purine (6-BA) or sucrose supplemented to the induction medium. The concentrations of 4.0 mg/L 2,4-D, 2 mg/L 6-BA, and 5 to 10 g/L sucrose were found optimal in maximizing initiation efficiency. For maturation, the efficiency, expressed as the number of mature somatic embryos per gram of fresh mass cultured (E/gFM), varied greatly with the choices of the basal medium and concentration of abscisic acid (ABA) of the maturation medium. Based on our results, the judicial choices were using the DCR medium as the basal medium and 10 mg/L ABA. The maturation efficiency could also be improved by adjusting the maturation medium&rsquo;s osmotic pressure by manipulating the concentrations of carbohydrate and Gelrite and culture density. While the maturation medium, using sucrose as carbohydrate source or supplemented with a low (&lt;8 g/L) Gelrite concentration, facilitated maturation, optimal selections were truly genotype-dependent. Our results also suggest that, while the optimal culture density varied with genotype, in general it is needless to culture more than 100 mg embryogenesis tissues per dish (size: 10 &times; 1.5 cm). Based on this study, the optimum pretreatment for embryogenesis tissue cryopreservation was culturing the tissues on the proliferation medium with 0.4 mol/L sorbitol for 24 h, followed by treatment with 5% Dimethyl sulfoxide. This study significantly improved the initiation (achieved a frequency of 0.56) and embryo maturation efficiencies (achieved 1030 E/gFM) and established an effective preculturing protocol for cryopreservation (recovered 1354 E/gFM) for the species. The protocols developed here, paired with the available ones for other SE steps in the literature, form a well-refined SE technology intended for commercial application to Picea pungens
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