Spatial Reorganization of Myoelectric Activities in Extensor Digitorum for Sustained Finger Force Production.

The study aims to explore the spatial distribution of multi-tendinous muscle modulated by central nervous system (CNS) during sustained contraction. Nine subjects were recruited to trace constant target forces with right index finger extension. Surface electromyography (sEMG) of extensor digitorum (ED) were recorded with a 32-channel electrode array. Nine successive topographic maps (TM) were obtained. Pixel wise analysis was utilized to extract subtracted topographic maps (STM), which exhibited inhomogeneous distribution. STMs were characterized into hot, warm, and cool regions corresponding to higher, moderate, and lower change ranges, respectively. The relative normalized area (normalized to the first phase) of these regions demonstrated different changing trends as rising, plateauing, and falling over time, respectively. Moreover, the duration of these trends were found to be affected by force level. The rising/falling periods were longer at lower force levels, while the plateau can be achieved from the initial phase for higher force output (45% maximal voluntary contraction). The results suggested muscle activity reorganization in ED plays a role to maintain sustained contraction. Furthermore, the decreased dynamical regulation ability to spatial reorganization may be prone to induce fatigue. This finding implied that spatial reorganization of muscle activity as a regulation mechanism contribute to maintain constant force production.

Early Intervention Improves Clinical Responses to House Dust Mite Immunotherapy in Allergic Rhinitis Patients.

BACKGROUND: Allergen immunotherapy (AIT) is the unique causal treatment for respiratory allergy. As AIT is expensive and of long duration, the availability of a marker predicting AIT responders is of crucial relevance. OBJECTIVE: To investigate clinical parameters correlated with effective AIT in allergic rhinitis (AR) patients. METHODS: This is a prospective, nonrandomized open study in which a total of 284 AR patients who had received house dust mite (HDM) subcutaneous AIT were enrolled from January 2011 to December 2015, and then followed up for 3 consecutive years. Demographic data, clinical history, laboratory tests (specific and total IgE levels), symptoms score, concomitant medication, and adverse reactions during AIT were collected. An AIT responder patient was defined when a visual analog score (assessing global symptoms) had decreased by >30% compared to baseline and concomitant medication was equal to or less than before AIT. RESULTS: Thirty-three patients dropped out, so 251 patients were analyzed; 175 (69.7%) patients were responders. This group had a higher baseline symptom score than the AIT nonresponder group (7.5 vs. 6.9). A significant negative correlation was found between AR symptom duration and the clinical response to AIT. Local reactions (LRs) during AIT had a positive correlation. Other variables such as a family history of atopy, combined asthma history, and the levels of specific and total IgE had no correlations with effective AIT. CONCLUSION: Early intervention with AIT helps to improve the efficacy of AR treatment. LRs might predict successful AIT. Highly symptomatic AR patients may develop increased clinical responses to AIT.

Analysis of influencing factors in permittivity of oxidized lignite by FTIR, XRD, and THz-TDS based on orthogonal experiment.

As an organic-rich and mineral-rich mixture, the permittivity of oxidized lignite is dependent on several factors in the terahertz (THz) band. In this study, thermogravimetric experiments were conducted to determine the characteristic temperatures of three types of lignite. The microstructural characteristics of lignite after treatment at 150, 300, and 450 °C were investigated by Fourier transform infrared spectroscopy and X-ray diffraction. The results show that the changes in the relative contents of CO and SiO are contrary to those of OH and CH3/CH2 with temperature variation. The relative content of CO is unpredictable at 300 °C. The aromaticity and crystallite diameter show a regular variation with temperature. The microcrystalline structure of coal tends to undergo graphitization with temperature. The variation of crystallite height is random at 450 °C. The uniform variation in microstructural characteristics of different types of lignite with oxidation temperature proves the feasibility of identifying oxidized lignite by THz spectroscopy. Based on orthogonal experiment results, the influence of the coal type, particle diameter, oxidation temperature, and moisture content on the permittivity of oxidized lignite in the THz band was arranged in an order. The order of the factors' sensitivity for real part of permittivity is oxidation temperature > moisture content > coal type > particle diameter. Similarly, the order of the factors' sensitivity for imaginary part of permittivity is oxidation temperature > moisture content > particle diameter > coal type. The results reveal the capability of THz technology to characterize the microstructure of oxidized lignite and provide guidance for minimizing error in THz technology.

Optimization of key parameters for continuous and precise nitrogen injection in goaf based on response surface methodology.

In order to solve the problems of coal spontaneous combustion, poor inerting effect of traditional nitrogen injection, and waste of resources in goaf, based on the response surface methodology and Box-Behnken combination test principle, the self-developed continuous and precise nitrogen injection and fire-fighting equipment was used to study the best possible combination of nitrogen injection position (20-90 m), nitrogen injection amount (10-70 m3/min), and air supply volume (2100-2500 m3/min), aiming to minimize the width of the oxidation zone and CO concentration in goaf. The optimal key parameters of continuous precise nitrogen injection were determined as follows: nitrogen injection position 54.17 m, nitrogen injection amount 31.04 m3/min, and air supply 2484.81 m3/min. Under this condition, the width of the oxidation zone was 29.21 ± 0.3 m and the CO concentration was 28.1 ± 4.4 ppm, which were similar to the predicted results of the model (the width of the oxidation zone was 29.41 m; CO concentration was 27.28 ppm). The reliability of the model was verified. These preliminary studies have achieved the purpose of rapid control of the fire in the whole region of the goaf and provided valuable lessons for similar nitrogen injection fire prevention and extinguishing technologies in goaf.

Middle-low-temperature oxidation and adsorption of arsenic from flue gas by Fe-Ce-based composite catalyst.

Fe-Ce-based composite catalysts were prepared and used for As2O3 catalytic oxidation and adsorption. They were characterized by XRD, BET, H2-TPR, Raman, SEM and XPS. The results suggests Fe, La and Zr can be partially doped into CeO2 lattice to form solid solutions. Compared with pure Fe2O3, the composite catalysts have stronger low-temperature reducibility, especially La3+ doping is beneficial to the formation of more low-temperature active sites. Raman and XPS measurements disclose the presence of oxygen vacancy and surface adsorbed oxygen in composite catalysts and these are more prominent in FeCeLaO. Ce3+ ratio increases to 18.30% after reaction, which confirms part of Ce4+ can participate in As2O3 oxidation and be reduced to Ce3+. The oxidation and adsorption capacity for As2O3 were investigated at different temperatures and O2 concentrations. The results show FeCeLaO exhibits excellent activity at middle-low-temperatures of 200-400 °C, the oxidation efficiency of As2O3 can reach 100%, the total adsorbed arsenic at 400 °C reaches 583.7 µg/g, which is 1.8 times of pure Fe2O3 at 600 °C. As2O3 oxidation mechanism over FeCeLaO with/without O2 was proposed through the Mars-Maessen theory with the aid of surface-active oxygen. The abundant oxygen vacancy defects and active chemisorbed oxygen play important roles and guarantee an efficient As2O3 oxidation, which is also the essential reason why the composite catalysts can effectively oxidize and adsorb As2O3 at middle-low-temperature of 200-400 °C, while pure Fe2O3 can only be at high temperature of 600-700 °C.

Evolution of pore characteristics and methane adsorption characteristics of Nanshan 1/3 coking coal under different stresses.

To ascertain the evolution of pore characteristics and methane adsorption characteristics of the unit cell of Nanshan 1/3 coking coal under different stresses, proximate analysis, ultimate analysis, solid-state 13C nuclear magnetic resonance spectroscopy (13C-NMR) and X-ray photoelectron spectroscopy (XPS) experiments were performed on the coal samples, and a molecular unit cell model of 1/3 coking coal was established. As the increase of stress, pore diameter, proportion of larger pores, number of pores, surface area, and pore volume all decrease, the rate of decrease gradually decreases, and the smaller pores are less affected. Under 8 kinds of stress, the methane adsorption capacity and the overall system energies all conform to the Langmuir adsorption curve; as the stress increases, the methane adsorption capacity and the overall system energies both decrease, the rate of decrease gradually decreases, and the order of the adsorbed methane increases. Stress changes the methane adsorption capacity by changing the pore characteristics of the unit cell, and the stress has a more obvious effect on larger pores. As the stress increases, the speed of the stress's influence on the pores weakens. This has certain guiding significance for studying the saturated adsorption capacity of methane under different original in-situ stresses.

Molecular insight into the diffusion/flow potential properties initiated by methane adsorption in coal matrix: taking the factor of moisture contents into account.

Coal seam permeability is one of the key parameters affecting coalbed methane (CBM), and plays an important role in resource evaluation and regional selection. To fully explore the diffusion/flow potential properties initiated by methane adsorption beneath diverse moisture contents (1-5%) in coal molecules. The pore size distribution and methane adsorption capacities were discussed based on Monte Carlo (MC) and molecular dynamics (MD) methods. The potential properties of diffusion/flow induced by methane adsorption were investigated using the maximum absolute adsorption capacities as benchmark. The variation patterns of the pore structure were analyzed using SEM scanning experiment to verify the results of simulation analysis. It is found that the free pores facilitate methane molecular adsorption and increase adsorption spaces; the skeleton pores restrict the flow and transport of water molecules. Reduction values in surface free energies increase at different temperatures, and released heat diffusion coefficients and permeabilities for methane molecules drop as moisture contents increase. Interestingly, however, enhancements in temperatures increase the methane molecular diffusion coefficients. The lower the activation energies, the easier they are to diffuse. Sufficiently, the optimum conditions for gas drainage of coal seam are at temperature of 293K and moisture content of 5%, indicating greater contributions to gas pressure relief for coal seam. By comparing the results of molecular simulation and SEM scanning, trend of change is basically the same. Moreover, it is explored that hydraulic measure was the most significant to the CBM stimulation technology through field engineering application. This research is expected to provide guidance for facilitating the effectiveness of gas extraction for coal seam.

Study on the optimal position of the roof low roadway based on the response surface methodology.

For determine the optimum position of the roof low roadway, the optimal solution is derived according to the response surface methodology. The UDEC numerical simulation of the overburden gives the porosity distribution of the strike fractured zone, the upper limit heights of the caving zone and the fractured zone are obtained as 18 m and 65 m, respectively. Based on the porosity distribution, the FLUENT numerical models of the goaf zone, air inlet roadway, air return roadway, working face and roof low roadway were established to simulate the gas concentration in the upper corner and gas drainage volume in roof low roadway during mining. Using the vertical and horizontal distance of the roof low roadway as the influencing factors, the experimental scheme of the position of the roof low roadway was designed according to the response surface method, and the response values were obtained from the FLUENT simulation experiments, predicting that the vertical and horizontal distances of the roof low roadway were 7.7 m and 5.9 m respectively when the interaction between the gas concentration in the upper corner and gas drainage volume in roof low roadway was optimal. Field tests showed that the average gas concentration in the upper corner and the average gas drainage volume in roof low roadway were 0.432% and 40.861 m3/min respectively, both of which were less than 10% of the error from the simulations. The design of the roof low roadway has effectively managed the gas accumulation problem in the upper corner.

Dynamic Simulation Based on a Simplified Model of 1/3 Coking Coal Molecule and Its Formation Characteristics of Hydration Films.

To comprehensively elaborate the formation characteristics of hydration films on 1/3 coking coal molecule, this paper reports the construction of a realistic simplified model for calculations of electrostatic potentials on the coal molecular surface to foresee the major immersion locations. On this basis, interactions at the interface of coal molecules with different numbers of water molecules and their effects on each functional group of coal molecules were investigated. Using the scanning electron microscopy experiment, changes in the coal matrix before and after water leaching were compared and analyzed by fractal dimension calculations. Hydration characteristics of coal were described from a combined macroscopic and microscopic perspective. The results showed that both positive and negative electrostatic potential of coal molecules occurred near the O-containing functional groups. The hydroxyl group's electrostatic potential (-OH) rose, resulting in higher electrostatic potential in coal-water molecules and providing many immersion sites. Deficiency in water molecules led to the complete immersion of water molecules. The interface of coal molecules could not be covered entirely, which led to the low number of active sites and Z values. The interface of coal-water molecules did not affect the average bond lengths of water molecules but decreased the bond angle by 3-4°. The influence ofwater molecules on the -OH groups of coal molecules was the most prominent when water molecules were incorporated into the coal molecules. Water damage for the coal matrix is more pronounced than in the raw coal itself. In view of above research, the formation characteristics of the hydration film from a microscopic point of view explained that the initial hydration of coal molecules was owing to H-bonds. From a macroscopic perspective, it was mainly due to structure changes for the coal matrix. This provides valuable references for field experiments in hydraulic fracturing and perforation.

The mysteries of rapidly destructive arthrosis of the hip joint: a systemic literature review.

Rapidly destructive arthrosis (RDA) is considered a rare and poorly diagnosed disease but is now seen more frequently in practice due to ageing populations. The most typical radiological features are flat femoral heads, absence of articular cartilage, subchondral bone destruction and signs of joint effusion. These features could be found on X-ray or magnetic resonance imaging (MRI). Surgeons should consider the presence of RDA when patients show rapid femoral head destruction. The purpose of this study is to review the distinct clinical features and successful treatments which may lead to the diagnosis and early handling of RDA. A comprehensive review of the literature was undertaken using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines with no language restrictions. Overall 23 publications with 17 detailed cases of RDA met the inclusion criteria. We found that the only prevalent factors associated with RDA were: (I) age greater than 60 years; (II) female gender; (III) presence of underlying systemic diseases such as rheumatoid arthritis, diabetes mellitus or systemic lupus erythematosus. Further studies should be conducted to clarify the histopathology and define the diagnosis as well as the treatment.

Study of the Dynamic Development Law of Overburden Breakage on Mining Faces.

Based on the geological conditions of overburden rock, the dynamic development law of overburden breakage was investigated by theoretical analysis and similarity model experiments in this paper. The formula of the compressive strength and No. ratio was obtained by testing the compressive strength of cylinder samples of similar materials. It can be seen from the overburden fracture evolution model established by theoretical calculations and similarity model experiments that the overlying rock layer's breakage law is consistent. Additionally, the height of the "three zones" and the law of the fracture angle are basically consistent. Obtaining the synchronous collapse of the overlying strata controlled by the key strata, the interval of the upper key strata is larger than that of the lower key strata, and the mining interval is approximately double the size of the deformed rock height. According to the overburden movement, the distribution law of the overburden separation rate is obtained. The strain in the stress concentration area is negative, and when the stress is released suddenly, the strain increases rapidly. Fracture development is detected by the p-wave velocity in the model. Moreover, certain guidance for the horizon selection of high and low-level gas drainage roadways is provided by this study.

Kinematic Synergy of Multi-DoF Movement in Upper Limb and Its Application for Rehabilitation Exoskeleton Motion Planning.

It is important for rehabilitation exoskeletons to move with a spatiotemporal motion patterns that well match the upper-limb joint kinematic characteristics. However, few efforts have been made to manipulate the motion control based on human kinematic synergies. This work analyzed the spatiotemporal kinematic synergies of right arm reaching movement and investigated their potential usage in upper limb assistive exoskeleton motion planning. Ten right-handed subjects were asked to reach 10 target button locations placed on a cardboard in front. The kinematic data of right arm were tracked by a motion capture system. Angular velocities over time for shoulder flexion/extension, shoulder abduction/adduction, shoulder internal/external rotation, and elbow flexion/extension were computed. Principal component analysis (PCA) was used to derive kinematic synergies from the reaching task for each subject. We found that the first four synergies can explain more than 94% of the variance. Moreover, the joint coordination patterns were dynamically regulated over time as the number of kinematic synergy (PC) increased. The synergies with different order played different roles in reaching movement. Our results indicated that the low-order synergies represented the overall trend of motion patterns, while the high-order synergies described the fine motions at specific moving phases. A 4-DoF upper limb assistive exoskeleton was modeled in SolidWorks to simulate assistive exoskeleton movement pattern based on kinematic synergy. An exoskeleton Denavit-Hartenberg (D-H) model was established to estimate the exoskeleton moving pattern in reaching tasks. The results further confirmed that kinematic synergies could be used for exoskeleton motion planning, and different principal components contributed to the motion trajectory and end-point accuracy to some extent. The findings of this study may provide novel but simplified strategies for the development of rehabilitation and assistive robotic systems approximating the motion pattern of natural upper-limb motor function.

Design, Optimization and Verification of 16S rRNA Oligonucleotide Probes of Fluorescence in-situ Hybridization for Targeting Clostridium spp. and Clostridium kluyveri.

Fluorescence in-situ hybridization (FISH) is a common and popular method used to investigate microbial communities in natural and engineered environments. In this study, two specific 16S rRNA-targeted oligonucleotide probes, CLZ and KCLZ, were designed and verified to quantify the genus Clostridium and the species Clostridium kluyveri. The optimal concentration of hybridization buffer solution for both probes was 30% (w/v). The specificity of the designed probes was high due to the use of pellets from pure reference strains. Feasibility was tested using samples of Chinese liquor from the famed Luzhou manufacturing cellar. The effectiveness of detecting target cells appears to vary widely in different environments. In pit mud, the detection effectiveness of the target cell by probes CLZ and KCLZ was 49.11% and 32.14%, respectively. Quantitative analysis by FISH technique of microbes in pit mud and fermented grains showed consistency with the results detected by qPCR and PCR-DGGE techniques, which showed that the probes CLZ and KCLZ were suitable to analyze the biomass of Clostridium spp. and C. kluyveri during liquor fermentation. Therefore, this study provides a method for quantitative analysis of Clostridium spp. and C. kluyveri and monitoring their community dynamics in microecosystems.

Risk factors and strategies in nonadherence with subcutaneous immunotherapy: a real-life study.

BACKGROUND: Allergen immunotherapy (AIT) is still the only causal treatment for allergic diseases. However, conventional subcutaneous immunotherapy (SCIT) administration schedules are time-consuming and patient nonadherence is a major barrier to achieving a satisfactory therapeutic effect. Our study aimed to analyze the causes leading to discontinuation of SCIT and to determine risk factors associated with nonadherence in respiratory allergies. METHODS: This was a prospective study. Patients with respiratory allergies who had received standardized dust mite SCIT were enrolled from January 2012 to January 2014. And a follow-up study on these subjects was conducted via telephone interviews on an interval of 3 months and online communication through social network applications. Reasons for discontinuation were documented when patients claimed to stop treatment. RESULTS: A total of 311 patients were enrolled in the study. The adherence rate at year 3 was 64.6%. Fifty-nine patients (19.0%) dropped out in year 1, 31 (10.0%) in year 2, and 20 (6.4%) in year 3. Reasons for nonadherence included inconvenience (32.7%), ineffectiveness (25.5%), improvement of symptoms (22.7%), and adverse reactions (14.5%). Children had higher adherence than adults (70.7% vs 55.0%) (p < 0.05). The dropout reasons were different among the children and adults groups (p < 0.005). The follow-up work was carefully and thoroughly done. All the 311 (100%) patients accepted the telephone interview, and 296 (95.2%) patients submitted questions and got rapid replies from doctors online. CONCLUSION: Adherence to SCIT was less than satisfactory in the real-life study. A close communication between doctors and patients is helpful in enhancing adherence with AIT in clinical practice.

Systemic Reactions to Dust Mite Subcutaneous Immunotherapy: A 3-Year Follow-up Study.

PURPOSE: The incidence of allergen specific immunotherapy-related systemic reactions (SRs) varies among different studies, and many factors are likely to contribute to SRs. This study aims to investigate the incidence, characteristics, and risk factors of SRs to standardize dust mite-specific subcutaneous immunotherapy (SCIT) in Central China. METHODS: All patients receiving standardized dust mites (100-100,000 SQ-U/mL; Alutard SQ, Hørsholn, Denmark) immunotherapy were followed up. Recorded data included demographics, diagnosis, patient status, pulmonary function testing results before and after each injection, allergen dosage, and details of SRs. RESULTS: From June 2011 to August 2014, a total of 208 patients received 4,369 injections; 27 (13.0%) patients experienced 48 (1.1%) systemic reactions. Most of the SRs were grade 2 reactions (n=30, 62.5%), followed by grade 1 (n=11, 22.9%), grade 3 (n=7, 14.6%), and no fatal reactions occurred. Forty-six SRs (95.8%) occurred within 30 minutes. Higher SR rates were associated with high concentration extracts (100,000 SQ-U/mL), injections with concomitant local reactions (LRs), children, asthma and high sensitivity (skin prick test 3+/4+ and/or sIgE≥17.5 kUA/L) (P<0.05). The estimated odds of SRs increased in children (OR=6.57; 95% CI: 1.88-22.97, P=0.003), asthmatic patients (OR=4.10; 95% CI: 1.72-9.80, P=0.002), and injections with LRs (OR=2.41; 95% CI: 1.33-4.36, P=0.004). CONCLUSIONS: The incidence of SRs to dust mite SCIT was low, and multiple factors were associated with the increased incidence of SRs. Children, asthmatics and patients with concomitant LR may be prone to develop SRs.

Feature study of hysterical blindness EEG based on FastICA with combined-channel information.

BACKGROUND: An appropriate feature study of hysteria electroencephalograms (EEG) would provide new insights into neural mechanisms of the disease, and also make improvements in patient diagnosis and management. OBJECTIVE: The objective of this paper is to provide an explanation for what causes a particular visual loss, by associating the features of hysterical blindness EEG with brain function. METHODS: An idea for the novel feature extraction for hysterical blindness EEG, utilizing combined-channel information, was applied in this paper. After channels had been combined, the sliding-window-FastICA was applied to process the combined normal EEG and hysteria EEG, respectively. Kurtosis features were calculated from the processed signals. As the comparison feature, the power spectral density of normal and hysteria EEG were computed. RESULTS: According to the feature analysis results, a region of brain dysfunction was located at the occipital lobe, O1 and O2. Furthermore, new abnormality was found at the parietal lobe, C3, C4, P3, and P4, that provided us with a new perspective for understanding hysterical blindness. CONCLUSIONS: Indicated by the kurtosis results which were consistent with brain function and the clinical diagnosis, our method was found to be a useful tool to capture features in hysterical blindness EEG.