Modular hip exoskeleton improves walking function and reduces sedentary time in community-dwelling older adults

Numerous studies showed that postural balance improves through light touch on a stable surface highlighting the importance of haptic information, seemingly downplaying the mechanical contributions of the support. The present study examined the mechanical effects of canes for assisting balance in healthy individuals challenged by standing on a beam. Sixteen participants supported themselves with two canes, one in each hand, and applied minimal, preferred, or maximum force onto the canes. They positioned the canes in the frontal plane or in a tripod configuration. Statistical analysis used a linear mixed model to evaluate the effects on the center of pressure and the center of mass. The canes significantly reduced the variability of the center of pressure and the center of mass to the same level as when standing on the ground. Increasing the exerted force beyond the preferred level yielded no further benefits, although in the preferred force condition, participants exploited the altered mechanics by resting their arms on the canes. The tripod configuration allowed for larger variability of the center of pressure in the task-irrelevant anterior–posterior dimension. High forces had a destabilizing effect on the canes: the displacement of the hand on the cane handle increased with the force. Given this static instability, these results show that using canes can provide not only mechanical benefits but also challenges. From a control perspective, effort can be reduced by resting the arms on the canes and by channeling noise in the task-irrelevant dimensions. However, larger forces exerted onto the canes can also have destabilizing effects and the instability of the canes needs to be counteracted, possibly by arm and shoulder stiffness. Insights into the variety of mechanical effects is important for the design of canes and the instructions of how to use them.     

我国医学SCIE研究型论文被撤销的原因分析

【目的】 分析2019—2020年我国学者发表在SCIE收录期刊上的医学研究型论文撤稿原因及其特征,为更有针对性地防范我国医学领域学术不端行为发生、完善科研诚信体系提供参考。【方法】 在撤稿观察数据库(Retraction Watch Database)中检索2019—2020年撤稿的我国医学SCIE研究型论文,提取撤销论文标题、作者姓名和单位、载文期刊名称、期刊出版商、撤稿原因等信息。应用GraphPad Prism 8.3.0软件进行描述性统计分析,对撤销论文发表期刊的影响因子和撤稿率进行Spearman相关性分析。【结果】 2019—2020年,我国医学SCIE研究型论文累计撤稿479篇,撤稿原因主要为关注或问题、重复发表、研究错误等,具体撤稿理由包括数据问题、图片问题、方法与结果问题、作者无回应等。撤销论文分布于194种期刊,其中PLoS ONE、European Review for Medical and Pharmacological Sciences、Journal of Cellular Biochemistry、OncoTargets and Therapy、Biosciences Reports居撤销论文数量前5位,Springer Nature、Elsevier和PLoS居撤销论文出版商前3位。撤销论文载文期刊影响因子与期刊撤稿率呈负相关。【结论】 我国学者发表的医学类SCIE研究型论文因数据和图片等问题而被撤稿的概率较高,应加强我国医学领域科研诚信体系建设,减少学术不端行为发生。     

Synthesis and automated fluorine-18 radiolabeling of new PSMA-617 derivatives with a CuAAC radiosynthetic approach

In the last decade, the development of new radiopharmaceuticals for the imaging and therapy of prostate cancer has been a highly active and important area of research, especially focusing on the prostate-specific membrane antigen (PSMA), an antigen which is upregulated in prostate, as well as in other tumor cells. A large variety of PSMA ligands have been radiolabeled, to date. Among the various derivatives, PSMA-617 resulted to be one of the most interesting in terms of interaction with the antigen and clinical properties, and its lutetium-177 labeled version has recently been approved by regulatory agencies for therapeutic purposes. For this reasons, the radiolabeling with fluorine-18 of a PSMA-617 derivative might be of interest. Beside other methodologies to radiolabel macromolecules with fluorine-18, the “click-chemistry” approach resulted to be very useful, and the copper-catalyzed azide-alkyne cycloaddition (CuAAC) is considered one of most efficient and reliable. This paper proposes the synthesis of a suitable precursor for the radiolabeling with fluorine-18 of a new PSMA-617 derivative. The whole radiosynthetic procedure has been fully automated, and the final product, which proved to be stable in plasma, has been obtained with radiochemical yield and purity suitable for subsequent preclinical studies.