634 research outputs found

    Climate change impact on China food security in 2050

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    Climate change is now affecting global agriculture and food production worldwide. Nonetheless the direct link between climate change and food security at the national scale is poorly understood. Here we simulated the effect of climate change on food security in China using the CERES crop models and the IPCC SRES A2 and B2 scenarios including CO2 fertilization effect. Models took into account population size, urbanization rate, cropland area, cropping intensity and technology development. Our results predict that food crop yield will increase +3-11 % under A2 scenario and +4 % under B2 scenario during 2030-2050, despite disparities among individual crops. As a consequence China will be able to achieve a production of 572 and 615 MT in 2030, then 635 and 646 MT in 2050 under A2 and B2 scenarios, respectively. In 2030 the food security index (FSI) will drop from +24 % in 2009 to -4.5 % and +10.2 % under A2 and B2 scenarios, respectively. In 2050, however, the FSI is predicted to increase to +7.1 % and +20.0 % under A2 and B2 scenarios, respectively, but this increase will be achieved only with the projected decrease of Chinese population. We conclude that 1) the proposed food security index is a simple yet powerful tool for food security analysis; (2) yield growth rate is a much better indicator of food security than yield per se; and (3) climate change only has a moderate positive effect on food security as compared to other factors such as cropland area, population growth, socio-economic pathway and technology development. Relevant policy options and research topics are suggested accordingly

    Promoting or inhibiting: The role of socio-economic integration on migrant entrepreneurship

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    Entrepreneurship plays a key role in promoting the global economic growth. However, the association between socio-economic integration and migrant entrepreneurship goes unnoticed. Based on 2017 China Migrants Dynamic Survey (CMDS), using a baseline regression model, Heckman two-stage model and IV Probit model, our research evidences a positive correlation between migrants’ integration into the society and their entrepreneurship. Specifically, for every standard deviation increase in the socio-economic integration level of migrants, the probability of having entrepreneurial engagement increases by 1.4%. Further findings indicates that migrant’s socio-economic integration is negatively correlated with migrant necessity-based entrepreneurship, while indicating a positive relationship between migrants’ socio-economic integration and opportunity-based entrepreneurship. The underlying mechanism of how socio-economic integration impacts migrant necessity-based entrepreneurship is through changes in the perception of difficulty and migrants’ settlement intention. The internal mechanism of how socio-economic integration influences migrant opportunity-based entrepreneurship is by changing localised social capital and migrants’ risk preference. More extensive investigations evidence that the degree of marketisation and the level of information have significant regulatory effect on the relationship between socio-economic integration and migrant entrepreneurship. Heterogeneity analysis shows that the relationship between socio-economic integration and migrant entrepreneurship varies across different levels of human capital, material capital and experience capital

    Intelligent Exploration for User Interface Modules of Mobile App with Collective Learning

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    A mobile app interface usually consists of a set of user interface modules. How to properly design these user interface modules is vital to achieving user satisfaction for a mobile app. However, there are few methods to determine design variables for user interface modules except for relying on the judgment of designers. Usually, a laborious post-processing step is necessary to verify the key change of each design variable. Therefore, there is a only very limited amount of design solutions that can be tested. It is timeconsuming and almost impossible to figure out the best design solutions as there are many modules. To this end, we introduce FEELER, a framework to fast and intelligently explore design solutions of user interface modules with a collective machine learning approach. FEELER can help designers quantitatively measure the preference score of different design solutions, aiming to facilitate the designers to conveniently and quickly adjust user interface module. We conducted extensive experimental evaluations on two real-life datasets to demonstrate its applicability in real-life cases of user interface module design in the Baidu App, which is one of the most popular mobile apps in China.Comment: 10 pages, accepted as a full paper in KDD 202

    Original Article Duodenal gangliocytic paraganglioma: report of two cases and review of literature

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    Abstract: We report two cases of Gangliocytic paraganglioma (GP), one of which was accompanied by lymph node metastasis. Histologically, the tumor was composed of three morphologically distinct cell populations: spindle cells, ganglion-like cells and epithelioid cells. The epithelioid cells were positive for cytokeratin (AE1/AE3), synaptophysin (Syn), chromogranin A (CgA), CD56 and progesterone receptor (PR). Ganglion-like cell types showed positive reactivity for Syn and CD56. In contrast, the spindle-shaped cells showed positive reactivity for S-100. The patient with lymph node metastasis has a good prognosis. Nonetheless, close surveillance is still necessary for patients with GP because a few cases of GP with regional lymph node metastasis and even distant metastasis have been published, including a malignant case of GP showing a lethal course

    Synchronous multimode ultrasound for assessing right-to-left shunt: a prospective clinical study

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    BackgroundRight-to-left shunt (RLS) is associated with several conditions and causes morbidity. In this study, we aimed to evaluate the effectiveness of synchronous multimode ultrasonography in detecting RLS.MethodsWe prospectively enrolled 423 patients with high clinical suspicion of RLS and divided them into the contrast transcranial Doppler (cTCD) group and synchronous multimode ultrasound group, in which both cTCD and contrast transthoracic echocardiography (cTTE) were performed during the same process of contrast-enhanced ultrasound imaging. The simultaneous test results were compared with those of cTCD alone.ResultsThe positive rates of grade II (22.0%:10.0%) and III (12.7%:10.8%) shunts and the total positive rate (82.1748%) in the synchronous multimode ultrasound group were higher than those in the cTCD alone group. Among patients with RLS grade I in the synchronous multimode ultrasound group, 23 had RLS grade I in cTCD but grade 0 in synchronous cTTE, whereas four had grade I in cTCD but grade 0 in synchronous cTTE. Among patients with RLS grade II in the synchronous multimode ultrasound group, 28 had RLS grade I in cTCD but grade II in synchronous cTTE. Among patients with RLS grade III in the synchronous multimode ultrasound group, four had RLS grade I in cTCD but grade III in synchronous cTTE. Synchronous multimode ultrasound had a sensitivity of 87.5% and specificity of 60.6% in the patent foramen ovale (PFO) diagnosis. Binary logistic regression analyses showed that age (odds ratio [OR] = 1.041) and risk of paradoxical embolism score ≥ 7 (OR = 7.798) were risk factors for stroke recurrence, whereas antiplatelets (OR = 0.590) and PFO closure with antiplatelets (OR = 0.109) were protective factors.ConclusionSynchronous multimodal ultrasound significantly improves the detection rate and test efficiency, quantifies RLS more accurately, and reduces testing risks and medical costs. We conclude that synchronous multimodal ultrasound has significant potential for clinical applications

    Risk Factors for Prognosis after the Maze IV Procedure in Patients with Atrial Fibrillation Undergoing Valve Surgery

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    The present study evaluated risk factors related to persistent atrial fibrillation (AF) at discharge (AF-d) and recurrent atrial fibrillation (rAF) and all-cause death after the maze IV procedure. Two hundred nineteen patients (63 female, aged 52.5±8.8 years) with valve disease and persistent AF undergoing valve surgery and the maze IV procedure in our center between 2015 and 2016 were included. Baseline demographic and clinical data were obtained by review of medical records. The median follow-up period was 27 months (interquartile range 21–34 months) in our patient cohort. The primary end point was all-cause death. The secondary end point was AF-d or rAF. rAF is defined as AF recurrence at 3 months or later after the procedure. Twenty-eight patients (12.8%) died during follow-up. Multiple logistic regression analysis showed that thrombocytopenia, elevated serum total bilirubin level, a larger right atrium, AF-d, and rAF were independent determinants for all-cause death after the maze IV procedure after adjustment for age, sex, and clinical covariates, including New York Heart Association class III/IV disease, hypertension, and aortic regurgitation, while valvular disease duration and left atrial diameter greater than 80.5 mm were independent determinants for AF-d, and thrombocytopenia, elevated serum total bilirubin level, higher mean pulmonary artery pressure, and AF-d were independent predictors for rAF. In conclusion, thrombocytopenia, elevated serum total bilirubin level, an enlarged right atrium, AF-d, and rAF are independent predictors of all-cause death in patients undergoing the maze IV procedure. </p

    Identification of RyR2-PBmice and the effects of transposon insertional mutagenesis of the RyR2 gene on cardiac function in mice

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    Ryanodine receptor 2 (RyR2) plays an important role in maintaining the normal heart function, and mutantions can lead to arrhythmia, heart failure and other heart diseases. In this study, we successfully identified a piggyBac translocated RyR2 gene heterozygous mouse model (RyR2-PBmice) by tracking red fluorescent protein (RFP) and genotyping PCR. Cardiac function tests showed that there was no significant difference between the RyR2-PBmice and corresponding wild-type mice (WTmice), regardless of whether they were in the basal state or injected with epinephrine and caffeine. However, the sarcoplasmic reticulum Ca2+ content was significantly reduced in the cardiomyocytes of RyR2-PBmice as assessed by measuring caffeine-induced [Ca2+]i transients; the cardiac muscle tissue of RyR2-PBmice displayed significant mitochondrial swelling and focal dissolution of mitochondrial cristae, and the tissue ATP content in the RyR2-PBmice heart was significantly reduced. To further analyze the molecular mechanism behind these changes, we tested the expression levels of related proteins using RT-PCR and Western blot analyses. The mRNA level of RyR2 in RyR2-PBmice cardiac tissue decreased significantly compared with the WTmice, and the protein expression associated with the respiratory chain was also downregulated. These results suggested that the piggyBac transposon inserted into the RyR2 gene substantively affected the structure and function of mitochondria in the mouse cardiomyocytes, leading to disorders of energy metabolism

    A Common SMAD7 Variant Is Associated with Risk of Colorectal Cancer: Evidence from a Case-Control Study and a Meta-Analysis

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    <div><h3>Background</h3><p>A common genetic variant, rs4939827, located in <em>SMAD7</em>, was identified by two recent genome-wide association (GWA) studies to be strongly associated with the risk of colorectal cancer (CRC). However, the following replication studies yielded conflicting results.</p> <h3>Method and Findings</h3><p>We conducted a case-control study of 641 cases and 1037 controls in a Chinese population and then performed a meta-analysis, integrating our and published data of 34313 cases and 33251 controls, to clarify the relationship between rs4939827 and CRC risk. In our case-control study, the dominant model was significant associated with increased CRC risk [Odds Ratio (OR) = 1.46; 95% confidence interval (95% CI), 1.19–1.80]. The following meta-analysis further confirmed this significant association for all genetic models but with significant between-study heterogeneity (all <em>P</em> for heterogeneity <0.1). By stratified analysis, we revealed that ethnicity, sample size, and tumor sites might constitute the source of heterogeneity. The cumulative analysis suggested that evident tendency to significant association was seen with adding study samples over time; whilst, sensitive analysis showed results before and after removal of each study were similar, indicating the highly stability of the current results.</p> <h3>Conclusion</h3><p>Results from our case-control study and the meta-analysis collectively confirmed the significant association of the variant rs4939827 with increased risk of colorectal cancer. Nevertheless, fine-mapping of the susceptibility loci defined by rs4939287 should be imposed to reveal causal variant.</p> </div
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