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11.
《Current biology : CB》2020,30(9):1703-1715.e5
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New records of four species (Lema lacertosa Lacordaire, 1845, Lema diversipes Pic, 1921, Lema cyanella (Linnaeus, 1758), Lema trivittata trivittata Say, 1824 and additional information on one recently recorded species (Lema solani Fabricius, 1798) are reported for Taiwan. Lema diversipes Pic, 1921 is removed from synonymy with Lema lacertosa Lacordaire, 1845; both species are redescribed. A lectotype is designated for Lema phungi Pic, 1924. The synonymies of Lema phungi Pic, 1924 and Lema jeanvoinei Pic, 1932 with Lema lacertosa Lacordaire, 1845 are supported. A revised key to the known species in Taiwan is provided. 相似文献
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Abstract Sexually mature male and female Rana esculenta L. were captured in their natural habitat in six phases of the annual cycle. Nuclear volumes in APOA cells were found to fluctuate distinctly in the course of the year. In both sexes nuclear volumes were maximal in the phases preceding the breeding season (IIIrd decade of January, and 1st decade of April), and minimal throughout the phases of active life (IIIrd decade of May, IInd decade of July, and 1st decade of September). No aldehydefuchsin or Gomori‐positive material was found in the APOA perikaryons. 相似文献
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David Ingram Christoph Engelhardt Alain Farron Alexandre Terrier Philippe Müllhaupt 《Computer methods in biomechanics and biomedical engineering》2016,19(4):450-463
Modelling the shoulder's musculature is challenging given its mechanical and geometric complexity. The use of the ideal fibre model to represent a muscle's line of action cannot always faithfully represent the mechanical effect of each muscle, leading to considerable differences between model-estimated and in vivo measured muscle activity. While the musculo–tendon force coordination problem has been extensively analysed in terms of the cost function, only few works have investigated the existence and sensitivity of solutions to fibre topology. The goal of this paper is to present an analysis of the solution set using the concepts of torque-feasible space (TFS) and wrench-feasible space (WFS) from cable-driven robotics. A shoulder model is presented and a simple musculo–tendon force coordination problem is defined. The ideal fibre model for representing muscles is reviewed and the TFS and WFS are defined, leading to the necessary and sufficient conditions for the existence of a solution. The shoulder model's TFS is analysed to explain the lack of anterior deltoid (DLTa) activity. Based on the analysis, a modification of the model's muscle fibre geometry is proposed. The performance with and without the modification is assessed by solving the musculo–tendon force coordination problem for quasi-static abduction in the scapular plane. After the proposed modification, the DLTa reaches 20% of activation. 相似文献
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The anterior cingulate cortex (ACC) is critical for brain functions including learning, memory, fear and pain. Long-term synaptic potentiation (LTP), a cellular model for learning and memory, has been reported in the ACC neurons. Unlike LTP in the hippocampus and amygdala, two key structures for memory and fear, little is known about the synaptic mechanism for the expression of LTP in the ACC. Here we use whole-cell patch clamp recordings to demonstrate that cingulate LTP requires the functional recruitment of GluR1 AMPA receptors; and such events are rapid and completed within 5-10 min after LTP induction. Our results demonstrate that the GluR1 subunit is essential for synaptic plasticity in the ACC and may play critical roles under physiological and pathological conditions. 相似文献
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Shear wave elastography (SWE) is emerging as an innovative tool to evaluate muscle properties and function. It has been shown to correlate with both passive and active muscle forces, and is sensitive to physiological processes and pathological conditions. Similarly, intramuscular pressure (IMP) is an important parameter that changes with passive and active muscle contraction, body position, exercise, blood pressure, and several pathologies. Therefore, the objective of this study was to quantify the dependency of shear modulus within the lower-leg muscles on IMP in healthy individuals. Nineteen healthy individuals (age: Mean age ± SD, 23.84 ± 6.64 years) were recruited. Shear modulus was measured using ultrasound SWE on the tibialis anterior (TA) and peroneus longus (PL) muscles using pressure cuff inflation around the thigh at 40 mmHg, 80 mmHg, and 120 mmHg. Changes in IMP were verified using a catheter connected to a blood pressure monitor. It was found that IMP was correlated to TA and PL shear modulus (spearman's rank correlation = 0.99 and 0.99, respectively). Applying a gradual increase of cuff pressure from 0 to 120 mmHg increased the shear modulus of the TA and PL muscles from 15.83 (2.46) kPa to 21.88 (4.33) kPa and from 9.64 (1.97) kPa to 12.88 (5.99) kPa, respectively. These results demonstrate that changes of muscle mechanical properties are dependent on IMP. This observation is important to improve interpretation of ultrasound elastograms and to potentially use it as a biomarker for more accurate diagnosis of pathologies related to increased IMP. 相似文献
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Low amplitude mechanical noise vibration has been shown to improve somatosensory acuity in various clinical groups with comparable deficiencies through a phenomenon known as Stochastic Resonance (SR). This technology showed promising outcomes in improving somatosensory acuity in other clinical patients (e.g., Parkinson’s disease and osteoarthritis). Some degree of chronic somatosensory deficiency in the knee has been reported following anterior cruciate ligament (ACL) reconstruction surgery. In this study, the effect of the SR phenomenon on improving knee somatosensory acuity (proprioception and kinesthesia) in female ACL reconstructed (ACLR) participants (n = 19) was tested at three months post-surgery, and the results were compared to healthy controls (n = 28). Proprioception was quantified by the measure of joint position sense (JPS) and kinesthesia with the threshold to detection of passive movement (TDPM).The results based on the statistical analysis demonstrated an overall difference between the somatosensory acuity in the ACLR limb compared to healthy controls (p = 0.007). A larger TDPM was observed in the ACLR limb compared to the healthy controls (p = 0.002). However, the JPS between the ACLR and healthy limbs were not statistically significantly different (p = 0.365). SR significantly improved JPS (p = 0.006) while the effect was more pronounced in the ACLR cohort. The effect on the TDPM did not reach statistical significance (p = 0.681) in either group.In conclusion, deficient kinesthesia in the ACLR limb was observed at three months post-surgery. Also, the positive effects of SR on somatosensory acuity in the ACL reconstructed group warrant further investigation into the use of this phenomenon to improve proprioception in ACLR and healthy groups. 相似文献
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Tomoyuki Kosaka Mutsumi Goda Manami Inoue Toshiharu Yakushi Mamoru Yamada 《Bioscience, biotechnology, and biochemistry》2019,83(7):1362-1371
The basic functions of a propionate-oxidizing bacterium Pelotomaculum thermopropionicum flagellum, such as motility and chemotaxis, have not been studied. To investigate its motility, we compared with that of Syntrophobacter fumaroxidans, an aflagellar propionate-oxidizing bacterium, in soft agar medium. P. thermopropionicum cells spread, while S. fumaroxidans cells moved downward slightly, indicating flagellum-dependent motility in P. thermopropionicum SI. The motility of P. thermopropionicum was inhibited by the addition of carbonyl cyanide m-chlorophenyl hydrazone, a proton uncoupler, which is consistent with the fact that stator protein, MotB of P. thermopropionicum, shared sequence homology with proton-type stators. In addition, 5-N-ethyl-N-isopropyl amiloride, an Na+ channel blocker, showed no inhibitory effect on the motility. Furthermore, motAB of P. thermopropionicum complemented the defective swimming ability of Escherichia coli ?motAB. These results suggest that the motility of P. thermopropionicum SI depends on the proton-type flagellar motor. 相似文献