Uncertainty evaluation at three spatial scales for the NDVI-based VWC estimation method used in the SMAP algorithm

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.     

腹膜前引流对腹腔镜经腹腹膜前疝修补术患者术后血肿及血清肿的影响

目的探讨腹腔镜经腹腹膜前疝修补术（TAPP）放置腹膜前引流对术后血肿及血清肿的影响。 方法选取2016年6月至2018年5月，江苏省苏州市中西医结合医院收治的单侧腹股沟疝患者90例，随机分为试验组和对照组，2组患者均行TAPP手术。试验组放置腹膜前引流管，对照组不放置引流管。收集2组患者的一般资料、手术相关资料及随访资料进行统计学分析，对比2组患者术后血肿及血清肿发生率差异。 结果全部患者均完成手术及随访。2组患者的一般资料、疝位置、疝分型、手术时间、住院花费、术后住院时间差异无统计学意义（P>0.05）。2组患者的术后发热发生率、急性疼痛发生率差异无统计学意义（P>0.05）。试验组术后血肿发生率明显低于对照组（P<0.05），试验组患者术后1和3个月血清肿发生率明显低于对照组，差异有统计学意义（P<0.05）。2组患者1年随访均观察到1例复发的病例，差异无统计学意义（P>0.05）；随访期内2组患者均未出现感染的病例。 结论TAPP中，放置腹膜前引流管能够有效降低患者术后血肿和血清肿的发生率，同时并不增加感染和复发风险。     

Assessment of the Antimetastatic Activity of Extracts of Filipedula ulmaria Depending on Extractant

Pharmaceutical Chemistry Journal - Three extracts were produced from the above-ground part of the meadowsweet Filipendula ulmaria (L.) Maxim. using water, 40% ethanol, and 70% ethanol. Comparative...     

Use of a dual lumen port for automated red cell exchange in adults with sickle cell disease

Red cell exchange (RCE) is a common procedure in adults with sickle cell disease (SCD). Implantable dual lumen Vortex (DLV) ports can be used for RCE in patients with poor peripheral venous access. We performed a retrospective cohort study of RCE procedures performed in adults with SCD. The main objective of the study was to compare the inlet speed, duration of procedures and rate of complications performed through DLV ports to those performed through temporary central venous and peripheral catheters. Twenty‐nine adults with SCD underwent a total of 318 RCE procedures. Twenty adults had DLV ports placed and 218 procedures were performed using DLV ports. Mean length of follow‐up after DLV port placement was 397 ± 263 days. Six DLV ports were removed due to infection and 1 for malfunction after a mean of 171 ± 120 days. Compared to temporary central venous and peripheral catheters, DLV port procedures had a greater rate of procedural complications, a longer duration, and a lower inlet speed (all P < 0.01). When accounting for the maximum allowable inlet speed to avoid citrate toxicity, 40% of DLV port procedures were greater than 10% below maximum speed, compared to 7 and 14% of procedures performed through temporary central venous and peripheral catheters (P < 0.0001). In conclusion, DLV ports can be used for RCE in adults with SCD, albeit with more procedural complications and longer duration. The smaller internal diameter and longer catheter of DLV ports compared to temporary central venous catheters likely accounts for the differences noted. J. Clin. Apheresis 30:353–358, 2015. © 2015 Wiley Periodicals, Inc.