脑卒中偏瘫患者步行时足底压力中心的特点

目的探讨脑卒中偏瘫患者步行时足底压力中心（COP）相关参数的特点及其与步速、不对称性的相关性。 方法选取60例能够独立步行的脑卒中偏瘫患者（偏瘫组）及健康中老年人（对照组），每组30例，2组受试者均以自我选择的步速进行步态测试，提取并计算步速及两侧下肢的单支撑时间、双支撑时间、单支撑期COP在前后方向的位移（AP-COPDS）及其速度(AP-COPVS)、双支撑期COP在前后方向的位移（AP-COPDD）及其速度（AP-COPVD），以及单支撑时间对称性比等参数，并分析和比较COP相关参数及其与步速、不对称性的相关程度。 结果对照组和偏瘫组的步速分别为（73.60±9.66）和（37.88±16.01）cm/s，偏瘫组步速较对照组明显下降（P<0.01）。偏瘫侧单支撑时间［（0.39±0.07）s］较对照组［（0.44±0.04）s］明显缩短（P<0.01）；非偏瘫侧的单支撑时间［（0.53±0.12）s］及两侧双支撑时间［（0.36±0.15）s、（0.36±0.21）s］均较对照组［（0.44±0.04）s及（0.15±0.03）s］延长（P<0.01）；偏瘫组患者两侧下肢所有COP相关参数均较对照组减小，且差异均有统计学意义（P<0.01）。偏瘫组两侧下肢所有COP相关参数均与步速呈高度正相关（r=0.765～0.967，P<0.01）；所有COP相关参数与单支撑时间对称性比呈不同程度正相关（r=0.505～0.764，P<0.01）。 结论脑卒中偏瘫患者步行时，足底负重在前后方向转移的能力下降，且与步速、单支撑时间对称性比呈正相关。     

Ballistic Resistance Training: Feasibility,Safety, and Effectiveness for Improving Mobility in Adults With Neurologic Conditions: A Systematic Review

ObjectivesTo determine whether ballistic resistance training is feasible, safe, and effective in improving muscle strength, power generation, and mobility in adults with neurologic conditions.Data SourcesNine electronic databases were searched from inception to March 2019 in addition to the reference lists of included articles.Study SelectionArticles were independently screened by 2 authors and were included if they were full-text; English-language articles published in a peer-reviewed journal; investigated ballistic resistance training for adults with a neurologic condition; and reported on feasibility, safety, strength, power, or mobility.Data ExtractionTwo authors independently extracted data. Study quality was assessed using the McMaster critical review form and the Physiotherapy Evidence Database scale.Data SynthesisThe search identified 1540 articles, with 13 articles describing 9 studies meeting the criteria for inclusion. Five studies were randomized controlled trials and 4 were cohort studies. Ballistic resistance training was feasible and safe with only 1 intervention-related adverse event reported. Findings indicated improvements in strength for hip abduction, leg press, knee flexion, and ankle dorsiflexion, but not for hip flexion, hip extension, knee extension, or ankle plantarflexion. Muscle power generation improved for hip flexion, hip abduction, leg press, knee extension, and knee flexion, but not for ankle plantarflexion. Treatment effect was positive for self-selected walking speed, with a standardized mean difference (SMD) of 0.69 (95% confidence interval [CI], 0.01-1.38) from 3 studies. However, fastest comfortable walking speed results were inconclusive with a SMD from 4 studies of 0.45 (95% CI, –0.01 to 0.91).ConclusionsBallistic training is safe and feasible for people with a neurologic condition. The effects on muscle strength, power generation, and mobility were found to be positive but not conclusive.     

Flight and Seizure Motor Patterns in Drosophila Mutants: Simultaneous Acoustic and Electrophysiological Recordings of Wing Beats and Flight Muscle Activity

Tethered flies allow studies of biomechanics and electrophysiology of flight control. We performed microelectrode recordings of spikes in an indirect flight muscle (the dorsal longitudinal muscle, DLMa) coupled with acoustic analysis of wing beat frequency (WBF) via microphone signals. Simultaneous electrophysiological recording of direct and indirect flight muscles has been technically challenging; however, the WBF is thought to reflect in a one-to-one relationship with spiking activity in a subset of direct flight muscles, including muscle m1b. Therefore, our approach enables systematic mutational analysis for changes in temporal features of electrical activity of motor neurons innervating subsets of direct and indirect flight muscles. Here, we report the consequences of specific ion channel disruptions on the spiking activity of myogenic DLMs (firing at ～5 Hz) and the corresponding WBF (～200 Hz). We examined mutants of the genes enconding: 1) voltage-gated Ca²⁺ channels (cacophony, cac), 2) Ca²⁺-activated K⁺ channels (slowpoke, slo), and 3) voltage-gated K⁺ channels (Shaker, Sh) and their auxiliary subunits (Hyperkinetic, Hk and quiver, qvr). We found flight initiation in response to an air puff was severely disrupted in both cac and slo mutants. However, once initiated, slo flight was largely unaltered, whereas cac displayed disrupted DLM firing rates and WBF. Sh, Hk, and qvr mutants were able to maintain normal DLM firing rates, despite increased WBF. Notably, defects in the auxiliary subunits encoded by Hk and qvr could lead to distinct consequences, that is, disrupted DLM firing rhythmicity, not observed in Sh. Our mutant analysis of direct and indirect flight muscle activities indicates that the two motor activity patterns may be independently modified by specific ion channel mutations, and that this approach can be extended to other dipteran species and additional motor programs, such as electroconvulsive stimulation-induced seizures.     

Complexity of visual stimuli affects visual illusion induced by sound

The fission illusion is induced by multisensory (audio-visual) integration. In the present study, we assume that perceptual efficiency affects the fission illusion’s rate because this illusion occurs in a short temporal range through the integration of visual and auditory information. The present study examined the effect of perceptual efficiency on the fission illusion by presenting visual patterns with various degrees of complexity. The results indicated that it was more difficult to induce the fission illusion when more complex visual patterns were used. The effect of pattern on the illusion differed according to the stimulus onset asynchrony between the first visual stimulus and the second auditory stimulus. These results suggest that the fission illusion has a higher probability of occurring when the perceptual process of the first visual stimulus is completed and integrated with the first beep before the presentation of the second beep. Thus, the audio-visual integration is affected by the perceptual efficiency of the physical stimuli.     

Analysis and Comparison of Friction Stir Welding and Laser Assisted Friction Stir Welding of Aluminum Alloy

Friction Stir Welding (FSW) is a solid-state joining process; i.e., no melting occurs. The welding process is promoted by the rotation and translation of an axis-symmetric non-consumable tool along the weld centerline. Thus, the FSW process is performed at much lower temperatures than conventional fusion welding, nevertheless it has some disadvantages. Laser Assisted Friction Stir Welding (LAFSW) is a combination in which the FSW is the dominant welding process and the laser pre-heats the weld. In this work FSW and LAFSW tests were conducted on 6 mm thick 5754H111 aluminum alloy plates in butt joint configuration. LAFSW is studied firstly to demonstrate the weldability of aluminum alloy using that technique. Secondly, process parameters, such as laser power and temperature gradient are investigated in order to evaluate changes in microstructure, micro-hardness, residual stress, and tensile properties. Once the possibility to achieve sound weld using LAFSW is demonstrated, it will be possible to explore the benefits for tool wear, higher welding speeds, and lower clamping force.     

从厥阴“络”“风”角度探讨高血压

高血压是心脑血管疾病最主要的危险因素，影响心、脑、肾等人体重要脏器的结构和功能。目前，我国高血压患病率居高不下，如何有效遏制高血压的发病率，减轻高血压患者靶器官损害，是眼下亟需解决的难题。中国传统医学，因为其独特的疗效和优势，目前正越来越多地在世界各地广泛应用。中医认为“风邪”是高血压发生发展的主要因素，且贯穿始终；与此同时，也有学者认为高血压位在络，络脉病变亦是高血压发生发展的重要原因。络病、风邪与高血压发生发展及心、脑、肾等靶器官损害疾病密切相关。从伤寒六经辨证角度来看，“络”“风”与厥阴关系密切，络病属厥阴，风邪始于厥阴，高血压的发生发展、持续存在与厥阴病密切相关。本文从厥阴“络”“风”角度浅析高血压的病机与论治，具体论述厥阴“络”“风”与高血压的关系，认为厥阴风火内郁，肝火上冲；厥阴虚损，肝风内动、络虚风动；厥阴外感，外风引动是导致高血压发生发展，心、脑、肾等靶器官损害的重要病机，并基于厥阴主方乌梅丸探讨厥阴“络”“风”同治之法。六经统百病，开后世之门径，基于厥阴“络”“风”角度探讨高血压病机与论治，对指导高血压的防治、减轻高血压患者靶器官损害、持续改善心脑血管病预后具有重要意义。     

Introduction of a new scaling approach for particle size reduction in toothed rotor-stator wet mills

A new scaling approach has been demonstrated for particle size reduction of an active pharmaceutical ingredient (API) in toothed rotor-stator wet mills for a wide range of wet milling conditions and scales. Compound A was crystallized by a cooling crystallization protocol in ethanol and wet milled with 2 types of lab scale mills and 1 pilot plant mill. The particle size was analyzed by FBRM (focused beam reflectance measurement), static light scattering and optical microscopy. The correlation between particle size and the energy input calculations, tailored for the toothed rotor-stator wet mill, had R² = 0.90 on a logarithmic plot. The new scaling approach forms the basis to correlate API particle size to energy input in toothed rotor-stator wet mills by accounting for wet mill tooth configuration and geometry, rotor tip speed and the probabilistic effects of collision such as shear frequency and slurry residence time.     

Assessing the benefits of napping and short rest breaks on processing speed in sleep‐restricted adolescents

Achievement‐oriented adolescents often study long hours under conditions of chronic sleep restriction, adversely affecting cognitive function. Here, we studied how napping and rest breaks (interleaved off‐task periods) might ameliorate the negative effects of sleep restriction on processing speed. Fifty‐seven healthy adolescents (26 female, age = 15–19 years) participated in a 15‐day live‐in protocol. All participants underwent sleep restriction (5 h time‐in‐bed), but were then randomized into two groups: one of these groups received a daily 1‐h nap opportunity. Data from seven of the study days (sleep restriction days 1–5, and recovery days 1–2) are reported here. The Blocked Symbol Decoding Test, administered once a day, was used to assess time‐on‐task effects and the effects of rest breaks on processing speed. Controlling for baseline differences, participants who took a nap demonstrated faster speed of processing and greater benefit across testing sessions from practice. These participants were also affected significantly less by time‐on‐task effects. In contrast, participants who did not receive a nap benefited more from the rest breaks that were permitted between blocks of the test. Our results indicate that napping partially reverses the detrimental effects of sleep restriction on processing speed. However, rest breaks have a greater effect as a countermeasure against poor performance when sleep pressure is higher. These data add to the growing body of evidence showing the importance of sleep for good cognitive functioning in adolescents, and suggest that more frequent rest breaks might be important in situations where sleep loss is unavoidable.