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《Gait & posture》2022
BackgroundOlder adults benefit most from engaging in higher-intensity physical activity, which is often determined using step rate thresholds. Fixed step rate thresholds that correspond to moderate (MPA) and vigorous-intensity physical activity (VPA) have been developed for heuristic activity promotion. The activPAL monitor uses step rate thresholds to determine activity intensity. Stepping thresholds may also vary based on body mass index (BMI) or aerobic fitness level in older adults. Despite the various thresholds used in the literature, it is unclear whether they produce similar outcomes.Research QuestionHow does time spent in physical activity intensities compare between different step rate thresholds in older adults?MethodsThirty-eight participants (24♀; 67 ± 4 years; BMI: 26.6 ± 4.4 kg/m2) wore an activPAL monitor 24-hr/day for up to 7-d (total: 205-d). Aerobic fitness (V̇O2max: 23 ± 8 ml/kg/min) was determined via indirect calorimetry during a maximal, graded cycling test. Time spent in each intensity category (light-physical-activity [LPA], MPA, VPA) was determined using the fixed (MPA/VPA) 100/130, 110/130, and activPAL step rate thresholds (74/212), as well as BMI-adjusted absolute (108.5 ± 2.5/134.0 ± 4.8) and BMI-adjusted relative (40%/60% V̇O2max; 111.4 ± 14.7/132.0 ± 19.0) cut-offs. Times spent in each intensity category were compared between methods.ResultsThe activPAL and 100/130 thresholds yielded less LPA and more MPA than all other methods. The activPAL had no time spent in VPA at all. The BMI-adjusted absolute and relative thresholds produced statistically equivalent time in LPA and MPA (via equivalence testing), but not VPA. No two methods yielded similar time spent in LPA, MPA, or VPA.SignificanceThe choice of step rate threshold has a major impact on physical activity intensity outcomes in older adults. Inherently, strategies that adjust for older adults’ body size and/or aerobic fitness level provide a more individualized data processing strategy than fixed thresholds that assume the same threshold for all older adults 相似文献
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以踝关节的生理解剖结构为理论依据,利用踝关节的CT图像作为二维数据源,通过医学图像处理软件Mimics建立踝关节的三维模型,然后使用3-matic对三维模型的网格进行优化,最后对优化前后的模型进行对比分析。结果发现经过优化后的踝关节三维模型在结构上与人体真实的踝关节结构并无明显的差异,精确程度满足要求,对于患者病情的分析及治疗方案的确立具有重要的指导意义。 相似文献
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目的建立不同炮制品组方五子衍宗丸(Wuzi Yanzong Pills,WYP)的HPLC指纹图谱,研究盐制对WYP化学成分的影响。方法采用HPLC法建立不同炮制品组方WYP的指纹图谱,并进行相似度评价,采用方差分析、聚类分析(CA)、主成分分析(PCA)与偏最小二乘法-判别分析(PLS-DA)对结果进行评价。结果 WYP全生品组、药典组、盐制组指纹图谱相似度均大于0.9,标定了18个共有峰,利用对照品指认出绿原酸(5号峰)、鞣花酸(10号峰)、金丝桃苷(11号峰)、异槲皮苷(12号峰)、毛蕊花糖苷(13号峰)、紫云英苷(14号峰)、槲皮素(15号峰)、山柰酚(17号峰)、五味子醇甲(18号峰)9个成分,归属性分析表明峰2来源于枸杞子,峰3、5、7、9、11、12、14、15、17来源于菟丝子,峰6、8、10、16来源于覆盆子,峰13来源于车前子,峰18来源于五味子,峰1是覆盆子和五味子共有成分,峰4是枸杞子和覆盆子共有成分。药物炮制后组方WYP未出现色谱峰的增加,但峰面积发生变化。通过CA将WYP全生品组、药典组、盐制组聚为3类,PCA筛选出4个主成分,PLS-DA标记出峰1、13(毛蕊花糖苷)、10(鞣花酸)、7、4、11(金丝桃苷)、12(异槲皮苷)、3、5(绿原酸)共9个差异性成分;绿原酸、鞣花酸、金丝桃苷、异槲皮苷、山柰酚、五味子醇甲及峰1、3、4、7、8共11个成分可能是不同炮制品组方WYP的差异标志物。结论建立的指纹图谱测定方法稳定、可靠,炮制后组方WYP的化学成分发生变化,结果可为WYP中如何选用药物炮制品提供一定的依据。 相似文献
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目的探究黄连Coptidis Rhizoma在连栀矾溶液传统发酵炮制中的作用。方法按照连栀矾溶液传统配方比例,将其拆分为3组配方溶液:连栀矾组(黄连+栀子+白矾)、黄连组(黄连+白矾)和栀子组(栀子+白矾),采用HPLC分析比较3组溶液发酵前后的化学成分变化轮廓,采用Illumina Hiseq高通量测序技术测定并比较发酵溶液中微生物的群落特征。结果传统配方连栀矾经发酵后环烯醚萜类成分发生了较显著的变化(P<0.05),生物碱类成分未发生明显变化,拆分后的黄连组中生物碱类成分和栀子组中环烯醚萜类成分均没有发生明显变化。分别对各组发酵溶液进行测序,根据α多样性分析结果,3组发酵液中真菌多样性为连栀矾组<栀子组<黄连组,真菌的丰富度为栀子组<连栀矾组<黄连组;细菌多样性为连栀矾组<黄连组<栀子组,细菌的丰富度为连栀矾组<栀子组<黄连组。根据β多样性分析结果,3组溶液中的真菌和细菌的群落结构均有明显差异。根据微生物相对丰度分析可知,3组的优势真菌均为子囊菌门、担子菌门和罗兹菌门,不同组间丰度无明显差异;真菌优势属中的孢霉属的丰度在连栀矾组最高,显著高于另外2组(P<0.05),栀子组又显著高于黄连组(P<0.05);韦斯特壳属的丰度在连栀矾组中最低,显著低于黄连组和栀子组(P<0.05),后两者间丰度无明显差异。3组的优势细菌均为变形菌门、厚壁菌门、放线菌门和拟杆菌门,其中连栀矾组中变形菌门的丰度极显著低于黄连组和栀子组(P<0.01),厚壁菌门的丰度在连栀矾组中极显著高于黄连组和栀子组(P<0.01),放线菌门和拟杆菌门的丰度在3组发酵溶液的差异较小;细菌优势菌属中的乳杆菌属在连栀矾组中显著高于黄连组和栀子组(P<0.05),在黄连组中也显著高于栀子组(P<0.05),伯克氏菌属丰度在黄连组和栀子组中无显著差异,都显著高于连栀矾组中的丰度(P<0.05)。结论连栀矾溶液配方中的黄连能提高其中栀子的有效成分的发酵转化,并且是通过对发酵体系中的优势菌属的丰度进行调节而发挥作用的。进一步佐证了传统配方制剂的合理性和科学性。 相似文献
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The fact that the transmission and processing of visual information in the brain takes time presents a problem for the accurate real-time localization of a moving object. One way this problem might be solved is extrapolation: using an object''s past trajectory to predict its location in the present moment. Here, we investigate how a simulated in silico layered neural network might implement such extrapolation mechanisms, and how the necessary neural circuits might develop. We allowed an unsupervised hierarchical network of velocity-tuned neurons to learn its connectivity through spike-timing-dependent plasticity (STDP). We show that the temporal contingencies between the different neural populations that are activated by an object as it moves causes the receptive fields of higher-level neurons to shift in the direction opposite to their preferred direction of motion. The result is that neural populations spontaneously start to represent moving objects as being further along their trajectory than where they were physically detected. Because of the inherent delays of neural transmission, this effectively compensates for (part of) those delays by bringing the represented position of a moving object closer to its instantaneous position in the world. Finally, we show that this model accurately predicts the pattern of perceptual mislocalization that arises when human observers are required to localize a moving object relative to a flashed static object (the flash-lag effect; FLE).SIGNIFICANCE STATEMENT Our ability to track and respond to rapidly changing visual stimuli, such as a fast-moving tennis ball, indicates that the brain is capable of extrapolating the trajectory of a moving object to predict its current position, despite the delays that result from neural transmission. Here, we show how the neural circuits underlying this ability can be learned through spike-timing-dependent synaptic plasticity and that these circuits emerge spontaneously and without supervision. This demonstrates how the neural transmission delays can, in part, be compensated to implement the extrapolation mechanisms required to predict where a moving object is at the present moment. 相似文献
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Sobia Nasir Laique Umar Hayat Shashank Sarvepalli Byron Vaughn Mounir Ibrahim John McMichael Kanza Noor Qaiser Carol Burke Amit Bhatt Colin Rhodes Maged K. Rizk 《Gastrointestinal endoscopy》2021,93(3):750-757
Background and AimsColonoscopy is commonly performed for colorectal cancer screening in the United States. Reports are often generated in a non-standardized format and are not always integrated into electronic health records. Thus, this information is not readily available for streamlining quality management, participating in endoscopy registries, or reporting of patient- and center-specific risk factors predictive of outcomes. We aim to demonstrate the use of a new hybrid approach using natural language processing of charts that have been elucidated with optical character recognition processing (OCR/NLP hybrid) to obtain relevant clinical information from scanned colonoscopy and pathology reports, a technology co-developed by Cleveland Clinic and eHealth Technologies (West Henrietta, NY, USA).MethodsThis was a retrospective study conducted at Cleveland Clinic, Cleveland, Ohio, and the University of Minnesota, Minneapolis, Minnesota. A randomly sampled list of outpatient screening colonoscopy procedures and pathology reports was selected. Desired variables were then collected. Two researchers first manually reviewed the reports for the desired variables. Then, the OCR/NLP algorithm was used to obtain the same variables from 3 electronic health records in use at our institution: Epic (Verona, Wisc, USA), ProVation (Minneapolis, Minn, USA) used for endoscopy reporting, and Sunquest PowerPath (Tucson, Ariz, USA) used for pathology reporting.ResultsCompared with manual data extraction, the accuracy of the hybrid OCR/NLP approach to detect polyps was 95.8%, adenomas 98.5%, sessile serrated polyps 99.3%, advanced adenomas 98%, inadequate bowel preparation 98.4%, and failed cecal intubation 99%. Comparison of the dataset collected via NLP alone with that collected using the hybrid OCR/NLP approach showed that the accuracy for almost all variables was >99%.ConclusionsOur study is the first to validate the use of a unique hybrid OCR/NLP technology to extract desired variables from scanned procedure and pathology reports contained in image format with an accuracy >95%. 相似文献
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目的探讨醋延胡索炮制前后HPLC指纹图谱与镇痛药效的相关性,筛选炮制特征成分。方法建立生延胡索与醋延胡索HPLC指纹图谱,对两者化学成分进行差异性分析,以大鼠扭体反应为模型建立评价指标,采用超氧化物歧化酶(superoxide dismutase,SOD)、丙二醛、孕酮、雌二醇、前列腺素E_2(prostaglandin E_2,PGE_2)、前列腺素F_(2a)(prostaglandin F_(2a),PGF_(2a))等指标评价镇痛药效,结合灰色关联度分析法与熵权法研究醋延胡索的谱-效关系,指认醋延胡索炮制特征成分。结果建立了不同批次生延胡索饮片、醋延胡索饮片的HPLC指纹图谱,确定了31个共有峰。生延胡索饮片与醋延胡索饮片均有止痛效果,以醋延胡索止痛效果最为显著。镇痛谱效关联度分析得到峰9、18~21、25、26醋炙后关联度得分有了显著的提升,与醋炙后镇痛疗效呈显著正相关。结论通过谱-效关系明确了醋延胡索炮制特征成分为原阿片碱、盐酸巴马汀、盐酸小檗碱、去氢紫堇碱、延胡索乙素、四氢小檗碱、延胡索甲素,为醋延胡索炮制质量控制提供一定依据。 相似文献
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