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1.
Vegetation water content (VWC) is the key input parameter for a soil moisture retrieval algorithm based on microwave remote sensing, and VWC uncertainty can limit the estimated accuracy of soil moisture. There has been little research on VWC algorithm development and validation in China, and the uncertainty of the VWC estimation method has not been well evaluated. Therefore, the aim of this study is to evaluate the uncertainty of the VWC estimation method used in the SMAP (Soil Moisture Active Passive) algorithm on three spatial scales (the point-scale, 30 m scale, and 1 km scale) for maize in northeast China. Results from three ground experimental datasets showed that the SMAP VWC estimation method was strongly biased with an average overestimation of 1.16 kg m?2,1.04 kg m?2, and 1.13 kg m?2 for the point-scale, 30 m scale, and 1 km scale respectively, and maximum bias occurred in the mid-stage of maize. Also, a new power relationship between NDVI (Normalized Difference Vegetation Index) and VWC was proposed for the 30 m scale based on Sentinel 2 NDVI and field VWC values from 2017 experiment, with respective R2 (coefficient of determination) and Root Mean Squared Error (RMSE) values of 0.80 and 0.67 kg m?2. The results confirmed that this power relationship was still suitable for VWC estimation at the 1 km scale, and it has smaller bias than the original SMAP VWC method. Future work will be carried out to evaluate the applicability of this VWC estimation method over a lager region. It is expected that it can improve the accuracy of soil moisture by providing high precision VWC input parameters.  相似文献   
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Based on the physical randomization of completely randomized experiments, in a recent article in Statistics in Medicine, Rigdon and Hudgens propose two approaches to obtaining exact confidence intervals for the average causal effect on a binary outcome. They construct the first confidence interval by combining, with the Bonferroni adjustment, the prediction sets for treatment effects among treatment and control groups, and the second one by inverting a series of randomization tests. With sample size n, their second approach requires performing O(n4)randomization tests. We demonstrate that the physical randomization also justifies other ways to constructing exact confidence intervals that are more computationally efficient. By exploiting recent advances in hypergeometric confidence intervals and the stochastic order information of randomization tests, we propose approaches that either do not need to invoke Monte Carlo or require performing at most O(n2)randomization tests. We provide technical details and R code in the Supporting Information . Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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Objective: To evaluate the effectiveness of a modified behavioral activation treatment (MBAT) intervention on reducing depressive symptoms in rural left-behind elderly.

Method: This is a randomized study registered in Chinese Clinical Trial Registry (ChiCTR-IOR-17011289). Eighty rural left-behind elderly people who had a Geriatric Depression Scale (GDS) score between 11 and 25 were randomly assigned to the intervention (n?=?40) and control group (n?=?40). The intervention group received both MBAT and regular treatment for 8 weeks while the control group received regular treatment. Both groups were assessed with the GDS, Beck Anxiety Inventory (BAI), and Oxford Happiness Questionnaire (OHQ) at baseline, immediately post-intervention, and at 3 months post-intervention.

Results: There were a total of 73 participants that completed the intervention. The scores of GDS and BAI decreased significantly, but the scores of OHQ increased significantly in the intervention group after 8 sessions of MBAT (P?<?.01). The reduction in depression symptoms after the intervention was maintained at the 3-month follow-up. Significant differences in GDS, BAI, and OHQ scores were observed between the intervention group and the control group (P?<?.01).

Conclusion: MBAT produced a significantly greater reduction in depressive symptoms than regular care in rural left-behind elderly.

Clinical or methodological significance of this article: A modified behavioral activation (BA) psychotherapy can significantly reduce the recurrence and seriousness of depression symptoms in the left-behind elderly with mild to moderate depression. This study also suggests that further study of the MBAT as an intervention will provide a direction for the management of mental health in rural left-behind elders.  相似文献   

5.
目的 收集藿香正气汤的主要活性成分,通过分子对接及网络药理学探讨其防控新型冠状病毒肺炎(COVID-19)的有效成分及治疗机制。方法 通过基于配体-蛋白质相互作用的计算方法,以瑞德西韦为对照,探索藿香正气汤潜在治疗COVID-19的成分,并选出对接较好成分进行药理学机制预测,初探其药理学机制。结果 本研究筛选出5种与新冠病毒3CLpro结合能力强于瑞德西韦的小分子成分。网络药理学初步预测抗病毒途径可能是通过PI3K-Akt 信号通路影响病毒复制。结论 成分C1-C5与3CLpro结合良好,推测其可能是潜在的3CLpro的抑制剂,为抗病毒天然药物的开发提供了理论依据。  相似文献   
6.
Stellate ganglion (SG) modification has been investigated for arrhythmia treatment. In this study, transesophageal SG imaging and intervention were explored using a homemade 30F integrated focused ultrasonic catheter in healthy mongrel canines in vivo. Anatomic details of SGs were ultrasonically imaged and evaluated. SG had a heterogeneous echoic structure and characteristic profiles sketched by hyper-echoic outlines in an ultrasonogram. Left SGs in the experimental group were successfully ablated through the esophagus under ultrasonic guidance provided by the catheter itself. Two weeks after the ablation, the QT and QTc of the experimental group decreased compared with those of the sham group and at baseline (both p values < 0.001). Histologic examination revealed that left SGs were destroyed. No major complications were observed. This approach may be further explored as a method for ganglia remodeling evaluation and as a strategy of ganglia modification for arrhythmia and for other diseases.  相似文献   
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目的分析25羟基维生素D[25(OH)D]水平对高血压合并冠心病患者心肌重构及左心室舒张功能的影响。方法选择80例高血压合并冠心病患者,根据左心室质量指数及左心室舒张功能分为心肌重构组和无心肌重构组、舒张功能障碍组和无舒张功能障碍组。Logistic回归分析影响高血压合并冠心病患者心肌重构及左心室舒张功能的独立危险因素,ROC曲线分析其诊断效能。结果与无心肌重构组比较,心肌重构组收缩压、总胆固醇(TC)、低密度脂蛋白胆固醇(LDLC)升高,25(OH)D降低(P<0.05)。与无舒张功能障碍组比较,舒张功能障碍组体质指数(BMI)、25(OH)D水平降低,LDLC升高(P<0.05)。25(OH)D是患者心肌重构及左心室舒张功能的危险因素(P<0.05)。25(OH)D水平对患者心肌重构、舒张功能障碍有较好的诊断效能。结论25(OH)D水平是影响高血压合并冠心病患者心肌重构及左心室舒张功能的独立危险因素,早期检测其水平有助于临床诊疗。  相似文献   
9.
In a biological microenvironment, free fatty acids (FFA) as ubiquitous biological molecules might interact with nanoparticles (NPs) and consequently change the toxicological responses. However, whether the chemical structures of FFA could influence their interactions with NPs remain unknown. This study investigated the interactions between ZnO NPs and saturated or unsaturated FFA (complexed to BSA), namely stearic acid (SA, C18:0), oleic acid (OA, C18:1), and α-linolenic acid (ALA, C18:3). It was shown that BSA, SA, OA, and ALA increased the atomic force microscope (AFM) heights as well the polydispersity index (PDI) of ZnO NPs. BSA modestly protected THP-1 macrophages from ZnO NP exposure, whereas OA and ALA led to relatively less cyto-protective effects of BSA. Moreover, only co-exposure to ZnO NPs and SA significantly promoted the release of interleukin-8. BSA, SA, OA, and ALA equally changed intracellular ROS and Zn ions associated with ZnO exposure, but co-exposure to ZnO NPs and OA/ALA particularly activated the expression of endoplasmic reticulum stress-apoptosis genes. In combination, these results showed that FFA could influence the colloidal aspects and toxicological signaling pathway of ZnO NPs, which is dependent on the number of unsaturated bonds of FFA.  相似文献   
10.
目的 针对中医药大数据平台传统的加密方案效率不高的问题,提出一种高效的基于属性的内积加密的数据脱敏算法。方法 Hash(哈希)算法是应用广泛的高效的数据加密方法,但传统的哈希算法基于单一的控制策略,效率不高。本文提出一种基于属性的内积加密的数据脱敏算法,把批量的敏感数据分割为不同长度数据颗粒度,与特定密文的哈希进行内积处理。结果 在面对中医药大数据平台的海量数据加密的场景,与传统的哈希加密算法相比,本文提供的加密算法具有很好的性能。结论 为了保障个人隐私数据不被泄露,中医药大数据平台中的个人医疗数据需要加密脱敏后,才能进行分析处理或对外发布。本文提出的算法具备灵活的数据颗粒度、策略和高效的性能表现,适用于海量的中医药数据脱敏。  相似文献   
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