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41.
Skeletal muscle injury is caused by a variety of events, such as muscle laceration, contusions, or strain. Muscle fibers respond to minor damage with immediate repair mechanisms that reseal the cell membrane. On the other hand, repair of irreversibly damaged fibers is achieved by activation of muscle precursor cells. Muscle repair is not always perfect, especially after severe damage, and can lead to excessive fibroblast proliferation that results in the formation of scar tissue within muscle fibers. Remaining scar tissue can impair joint movement, reduce muscular strength, and inhibit exercise ability; therefore, to restore muscle function, minimizing the extent of injury and promoting muscle regeneration are necessary. Various physical agents, such as cold, thermal, electrical stimulation, and low-intensity pulsed ultrasound therapy, have been reported as treatments for muscle healing. Although approaches based on the muscle regeneration process have been under development, the most efficacious physiological treatment for muscle injury remains unclear. In this review, the influence of these physical agents on muscle injury is described with a focus on research using animal models.  相似文献   
42.
We present a new Multiple-Observations (MO) helper data scheme for secret-key binding to an SRAM-PUF. This MO scheme binds a single key to multiple enrollment observations of the SRAM-PUF. Performance is improved in comparison to classic schemes which generate helper data based on a single enrollment observation. The performance increase can be explained by the fact that the reliabilities of the different SRAM cells are modeled (implicitly) in the helper data. We prove that the scheme achieves secret-key capacity for any number of enrollment observations, and, therefore, it is optimal. We evaluate performance of the scheme using Monte Carlo simulations, where an off-the-shelf LDPC code is used to implement the linear error-correcting code. Another scheme that models the reliabilities of the SRAM cells is the so-called Soft-Decision (SD) helper data scheme. The SD scheme considers the one-probabilities of the SRAM cells as an input, which in practice are not observable. We present a new strategy for the SD scheme that considers the binary SRAM-PUF observations as an input instead and show that the new strategy is optimal and achieves the same reconstruction performance as the MO scheme. Finally, we present a variation on the MO helper data scheme that updates the helper data sequentially after each successful reconstruction of the key. As a result, the error-correcting performance of the scheme is improved over time.  相似文献   
43.
Objective: Exercise therapy to strengthen quadriceps muscle is recommended in rehabilitation program for people with patellofemoral pain syndrome (PFPS). This study aimed to investigate the electromyography (EMG) activity of vastus medialis obliquus (VMO), vastus lateralis (VL) and VMO/VL ratio during PNF in individuals with and without PFPS. Methods: 26 persons with PFPS and 26 healthy subjects participated to study. All subjects performed PNF patterns (Flexion-Adduction-External Rotation (D1FL), Extension-Adduction-External Rotation (D2EX), D1FL+ load, D2EX+ load) and straight leg raise (SLR). The normalized EMG activity of VMO, VL and VMO/VL ratio were measured and analyzed using repeated measure ANOVA. Results: There were significant main effects of group and exercises for the both VMO and VL (p<0.05). It was found that except SLR and D2EX, in the other motions PFPS group had lower VMO activity compared to healthy group (p<0.05). For VL except SLR, in the other motions PFPS group had lower VL activity too (p<0.05). The PNF patterns activated VMO more than SLR, however it was not significant (p>0.05). Also; there weren''t any significant difference between the two groups in VMO/VL activation ratios. Also, performing the PNF patterns with load increased VMO and VL muscles activity significantly (p<0.05). It also found that in PFPS group the VMO/VL ratio values in PNF patterns were significantly more than SLR and the highest VMO/VL ratio value (0.96) was found during D2EX. Conclusion: The PNF patterns due to provide optimal VMO/VL ratio value than SLR and proper balance between these two muscles can be recommended in rehabilitation of individuals with PFPS.  相似文献   
44.
We proposed a method to find the community structure in a complex network by density-based clustering. Physical topological distance is introduced in density-based clustering for determining a distance function of specific influence functions. According to the distribution of the data, the community structures are uncovered. The method keeps a better connection mode of the community structure than the existing algorithms in terms of modularity, which can be viewed as a basic characteristic of community detection in the future. Moreover, experimental results indicate that the proposed method is efficient and effective to be used for community detection of medium and large networks.  相似文献   
45.
ABSTRACT

Structures of small lengths of capped (3,3), (4,4) and (5,5) single-walled carbon nanotubes (SWCNTs) and their structures decorated by Pt atom and Ptn clusters (n = 2–4) were obtained using density functional theory calculations. Binding abilities of Pt atom and Ptn clusters on the outer surface of SWCNTs at various adsorption sites were explored. Adsorptions of H2 onto Pt atom of the Pt-decorated (3,3), (4,4) and (5,5) SWCNTs were studied and their adsorption energies are reported. The thermodynamic properties and equilibrium constants for H2 adsorptions on the Pt4-decorated (3,3), (4,4) and (5,5) SWCNTs were obtained. The adsorption of H2 on the Pt atom of the Pt4/(3,3) SWCNT was found to be the most preferred reaction of which enthalpy and free energy changes at room temperature are ?46.61 and ?23.99 kcal/mol, respectively.  相似文献   
46.
Two samples of potassium zinc hexacyanoferrate were prepared using two different ratios of the initial materials. The distribution coefficient of Eu3+ on the two samples was determined. The effect of the cation concentration in the aqueous phase on the adsorption of Eu3+ was also studied. The mechanism of the exchange process was described on the light of the data obtained, and the equilibrium constant of the exchange reaction was also calculated.  相似文献   
47.
ABSTRACT

The concentration of carbon dioxide (CO2) has a significant influence on the morphology of thermal decomposition products of magnesite. So, structures, stabilities and adsorption mechanisms of (MgO)m (m?=?1–6) clusters by one or two CO2 molecules were calculated by the GGA-PW91 method. The results show that the stability of the considered clusters is (MgO)m(CO2)2 clusters > (MgO)m(CO2) clusters > (MgO)m clusters by the average binding energy. Certain low-lying isomers of (MgO)m(CO2) and (MgO)m(CO2)2 clusters which have an isolated O atom are deviating from the cluster center which possess higher kinetic activity. (MgO)m clusters prefer to adsorb a CO2 molecule, while (MgO)3(CO2) clusters prefer to adsorb a CO2 molecule rather than the neighbors. Magnesite is difficult to transit to (MgCO3)2 clusters at room temperature. However, magnesite will spontaneously transit to (MgO)2 clusters and further transit to MgO crystal which need to adsorb more energy at 700?K.  相似文献   
48.
刘城  雷洁红 《强激光与粒子束》2020,32(10):102001-1-102001-7
运用理论分析方法计算研究了水分子在氢化锂表面的吸附行为,分析了氢化锂表面改性对其疏水性能的影响。结果表明,在LiH-111面和LiH-100面上构建槽结构、柱状结构后,水分子在其上的吸附力比完整表面更强,说明表面微结构的引入的确改变了势能分布。壁相交处存在势能叠加,加强了吸附水分子的能力,但是没有引起表面的亲水性能变化。水分子可以稳定的吸附在完美的LiH(001)表面,其解离能垒仅为0.386 eV,这一解离反应在室温下完全可以进行。水分子极易在具有结构缺陷的LiH表面解离,这是LiH在一定湿度的空气和水环境中极易分解的根本原因。  相似文献   
49.
Metal organic frameworks (MOFs) have been well-known and extensively researched due to the high storage /good selectivity for gas molecules. Herein, the structures and electron paramagnetic resonance (EPR) spectra for dicopper paddle wheel MOF compound (Cu22-O2CCH3)4 with various gas molecule are theoretically investigated by density functional theory (DFT) calculations. The adsorption energies and isotherms (including pure gas molecules and the mixed ones) are calculated for the gas molecules interacting with the unsaturated Cu22-O2CCH3)4. Both quantities exhibit the roughly consistent orders (e.g. H2S?>?NH3?>?CO2?>?CO?>?H2O?>?N2?>?NO?>?H2 for isotherms and H2S?>?NH3?>?N2?>?CO2?>?NO?>?H2O?>?H2?>?CO for adsorption energies), possibly suggesting that this material may act as a potential adsorbent of these gas molecules. The catalytic property of Cu22-O2CCH3)4 for oxidation of CO and NO into non-toxic molecules and splitting of H2O into H2 and O2 in the solvent condition are uniformly discussed. Simulation of Grand Canonical Monte Carlo (GCMC) in MS 8.0 and calculations in Langmuir model reveal that Cu22-O2CCH3)4 has good selectivity for CH4 in natural gas (CH4/CO2/N2) and SO2 in fog (SO2/NO/NO2/H2O/O2), which would exhibit potential environmentally friendly applications.  相似文献   
50.
基于耦合非线性薛定谔方程,采用分步傅里叶方法分析了在单波长信道和WDM(波分复用)4波长信道中XPM(交叉相位调制)对高速NOLM(非线性光纤环镜)光开关中脉冲传输的影响.数值计算表明:XPM造成NOLM中信号脉冲串扰与畸变,并造成NOLM开关性能的下降.WDM系统NOLM光纤环中的同向传播的各波长之间的XPM串扰比相向脉冲之间的XPM效应的影响更大,并且波长越短输出功率越低,中间信道受XPM的影响所导致的脉座现象和走离效应比两侧波长信道严重.  相似文献   
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