Estimation of electrical muscle activity during gait using inertial measurement units with convolution attention neural network and small-scale dataset.

In general, muscle activity can be directly measured using Electromyography (EMG) or calculated with musculoskeletal models. However, both methods are not suitable for non-technical users and unstructured environments. It is desired to establish more portable and easy-to-use muscle activity estimation methods. Deep learning (DL) models combined with inertial measurement units (IMUs) have shown great potential to estimate muscle activity. However, it frequently occurs in clinical scenarios that a very small amount of data is available and leads to limited performance of the DL models, while the augmentation techniques to efficiently expand a small sample size for DL model training are rarely used. The primary aim of the present study was to develop a novel DL model to estimate the EMG envelope during gait using IMUs with high accuracy. A secondary aim was to develop a novel model-based data augmentation method to improve the performance of the estimation model with small-scale dataset. Therefore, in the present study, a time convolutional network-based generative adversarial network, namely MuscleGAN, was proposed for data augmentation. Moreover, a subject-independent regression DL model was developed to estimate EMG envelope. Results suggested that the proposed two-stage method has better generalization and estimation performance than the commonly used existing methods. Pearson correlation coefficient and normalized root-mean-square errors derived from the proposed method reached up to 0.72 and 0.13, respectively. It was indicated that the MuscleGAN indeed improved the estimation accuracy of lower limb EMG envelope from 70% to 72%. Thus, even using only two IMUs and a very small-scale dataset, the proposed model is still capable of accurately estimating lower limb EMG envelope, demonstrating considerable potential for its application in clinical and daily life scenarios.

Estimation of Lower Limb Joint Angles and Joint Moments during Different Locomotive Activities Using the Inertial Measurement Units and a Hybrid Deep Learning Model.

Using inertial measurement units (IMUs) to estimate lower limb joint kinematics and kinetics can provide valuable information for disease diagnosis and rehabilitation assessment. To estimate gait parameters using IMUs, model-based filtering approaches have been proposed, such as the Kalman filter and complementary filter. However, these methods require special calibration and alignment of IMUs. The development of deep learning algorithms has facilitated the application of IMUs in biomechanics as it does not require particular calibration and alignment procedures of IMUs in use. To estimate hip/knee/ankle joint angles and moments in the sagittal plane, a subject-independent temporal convolutional neural network-bidirectional long short-term memory network (TCN-BiLSTM) model was proposed using three IMUs. A public benchmark dataset containing the most representative locomotive activities in daily life was used to train and evaluate the TCN-BiLSTM model. The mean Pearson correlation coefficient of joint angles and moments estimated by the proposed model reached 0.92 and 0.87, respectively. This indicates that the TCN-BiLSTM model can effectively estimate joint angles and moments in multiple scenarios, demonstrating its potential for application in clinical and daily life scenarios.

Effects of lumbar-pelvic training combined with electroacupuncture on chronic nonspecific low back pain.

This observational study was conducted to investigate the effect of lumbar-pelvic training (LP) combined with electroacupuncture (EA) in the treatment of chronic nonspecific low back pain. One hundred and twenty patients diagnosed with chronic nonspecific low back pain were evenly randomized to receive the following 4 treatments for 2 weeks: LP combined with EA (Group A), EA (Group B), LP (Group C) or no intervention (Group D). The LP was a self-developed training program containing 5 movements and was conducted three times a week to build up the strength of abdomen muscle groups. Four acupoints along the foot-taiyang bladder meridian and the governor vessel were chosen for EA five times a week based on the theory of Traditional Chinese Medicine. The Visual Analog Scale and Oswestry Disability Index were measured before and after treatment to assess the reduction of pain intensity and functional disability, respectively. Following the treatments, Visual Analog Scale and Oswestry Disability Index scores in all 3 intervention groups were significantly lower than those in the Group D without intervention (P < .01). Among the intervention groups, Group A's scores were lower than those of Group B or Group C (P < .01). The overall efficacy of Group A was 93.33%, which was higher than that of Group B (76.67%) and Group C (70.00%) (P < .01). In conclusion, this study suggest that our self-developed lumbar-pelvic training combined with electroacupuncture is effective for chronic nonspecific low back pain in terms of pain and disability reduction.

Extended Application of Inertial Measurement Units in Biomechanics: From Activity Recognition to Force Estimation.

Abnormal posture or movement is generally the indicator of musculoskeletal injuries or diseases. Mechanical forces dominate the injury and recovery processes of musculoskeletal tissue. Using kinematic data collected from wearable sensors (notably IMUs) as input, activity recognition and musculoskeletal force (typically represented by ground reaction force, joint force/torque, and muscle activity/force) estimation approaches based on machine learning models have demonstrated their superior accuracy. The purpose of the present study is to summarize recent achievements in the application of IMUs in biomechanics, with an emphasis on activity recognition and mechanical force estimation. The methodology adopted in such applications, including data pre-processing, noise suppression, classification models, force/torque estimation models, and the corresponding application effects, are reviewed. The extent of the applications of IMUs in daily activity assessment, posture assessment, disease diagnosis, rehabilitation, and exoskeleton control strategy development are illustrated and discussed. More importantly, the technical feasibility and application opportunities of musculoskeletal force prediction using IMU-based wearable devices are indicated and highlighted. With the development and application of novel adaptive networks and deep learning models, the accurate estimation of musculoskeletal forces can become a research field worthy of further attention.

Baohuoside I Inhibits Osteoclastogenesis and Protects Against Ovariectomy-Induced Bone Loss.

Bone-resorbing osteoclasts are essential for skeletal remodelling, and the hyperactive formation and function of osteoclasts are common in bone metabolic diseases, especially postmenopausal osteoporosis. Therefore, regulating the osteoclast differentiation is a major therapeutic target in osteoporosis treatment. Icariin has shown potential osteoprotective effects. However, existing studies have reported limited bioavailability of icariin, and the material basis of icariin for anti-osteoporosis is attributed to its metabolites in the body. Here, we compared the effects of icariin and its metabolites (icariside I, baohuoside I, and icaritin) on osteoclastogenesis by high-content screening followed by TRAP staining and identified baohuoside I (BS) with an optimal effect. Then, we evaluated the effects of BS on osteoclast differentiation and bone resorptive activity in both in vivo and in vitro experiments. In an in vitro study, BS inhibited osteoclast formation and bone resorption function in a dose-dependent manner, and the elevated osteoclastic-related genes induced by RANKL, such as NFATc1, cathepsin K, RANK, and TRAP, were also attenuated following BS treatment. In an in vivo study, OVX-induced bone loss could be prevented by BS through interrupting the osteoclast formation and activity in mice. Furthermore, mechanistic investigation demonstrated that BS inhibited osteoclast differentiation by ameliorating the activation of the MAPK and NF-kB pathways and reducing the expression of uPAR. Our study demonstrated that baohuoside I could inhibit osteoclast differentiation and protect bone loss following ovariectomy.

Green synthesis of 1,5-dideoxy-1,5-imino-ribitol and 1,5-dideoxy-1,5-imino-DL-arabinitol from natural D-sugars over Au/Al2O3 and SO42-/Al2O3 catalysts.

A green synthetic route for the synthesis of some potential enzyme active hydroxypiperidine iminosugars including 1,5-dideoxy-1,5-imino-ribitol and 1,5-dideoxy-1,5-imino-DL-arabinitol, starting from commercially available D-ribose and D-lyxose was tested out. Heterogeneous catalysts including Au/Al2O3, SO42-/Al2O3 as well as environmentally friendly reagents were employed into several critical reaction of the route. The synthetic route resulted in good overall yields of 1,5-dideoxy-1,5-imino-ribitol of 54%, 1,5-dideoxy-1,5-imino-D-arabinitol of 48% and 1,5-dideoxy-1,5-imino-L-arabinitol of 46%. The Au/Al2O3 catalyst can be easily recovered from the reaction mixture and reused with no loss of activity.

Study of Siloxane Adsorption on Hard Disk Media Surface.

Siloxane adsorption on disk surfaces is investigated as a function of lubricant film thickness and carbon film composition through several analytical technologies including FTIR, XPS, TOF-SIMS, GC-MS, and Candela OSA. Disk parameters that govern the propensity for siloxane adsorption are identified. Lubricant film coverage, taken as the fractional monolayer thickness, is found to be the most significant determinant. Siloxane adsorption decreases with increasing lubricant film coverage. The nitrogen content of the underlying carbon film is also found to be a determinant for submonolayer lubricant films: On the one side, siloxane adsorption on carbon films increases with increasing atom % nitrogen in carbon films. On the other side, the lubricant monolayer film thickness increases with increasing atom % N in carbon films, i.e., lubricant film coverage decreases with increasing atom % N. Thus, increasing atom % N in carbon films leads to increasing siloxane adsorption.

Preliminary exploration of 3D printed individualized applicator for 3D-image-guided intracavitary HDR-brachytherapy for nasopharyngeal carcinoma / 中华放射肿瘤学杂志

Objective To explore the feasibility of 3D printed individualized applicator for the intracavitary HDR-brachytherapy for nasopharyngeal carcinoma.Methods CT scan was performed in 1 case of recurrent rT1 nasopharyngeal carcinoma and 1 case of T2 residual nasopharyngeal carcinoma and the obtained images were transmitted to 3D image processing software.The geometric contour parameters of the nasopharyngeal cavity were obtained and a pipeline was designed to make it close to the recurrent gross tumor volume (rGTV).Individualized cavity applicators were created by using 3D printer.The applicator was inserted into the patient's nasopharyngeal cavity through oral cavity.The source tube and false source were inserted into the preset pipe of the applicator.CT scan was performed again and the images were transmitted to the 3D brachytherapy planning system.Mter delineating the target volume and organ at risk,treatment plan was optimized.After completing the first treatment,the applicator was removed.Before second treatment in a few days,CT scan was reviewed to confirm whether the position was correct.Results When the applicator was inserted into the nasopharyngeal cavity,it could be fully aligned with the nasopharyngeal wall and self-fixed without additional fixation measures.Comparing the location of false source in multiple reviews of CT scan,the error was ≤ 1 mm.No significant discomfort was reported throughout the treatment.In optimized three-dimensional treatment,100％ prescription dose curve included the full rGTV,maximum dose of the brain stem and spinal cord was＜30％ prescription dose.Recurrent patients were given with a prescription dose of DT 40Gy/8 fractions/4 weeks and patients with residual tumors were given with 12Gy/2 fractions/1 week.No tumor recurrence was observed at postoperative 3 months in two cases.Conclusions The 3D printed individualized nasopharyngeal intracavitary applicator has the advantages of self-fixation,accurate location,good repeatability and good patient tolerance.The short-term outcome is effective,whereas its long-term clinical effect and adverse reactions need to be further observed.

Clostridium swellfunianum sp. nov., a novel anaerobic bacterium isolated from the pit mud of Chinese Luzhou-flavor liquor production.

A novel Gram-positive, strictly anaerobic, spore-forming, rod-shaped bacterium, designated strain S11-3-10(T), was isolated from the pit mud used for Chinese Luzhou-flavor liquor production. Phylogenetic analysis based on 16S rRNA gene sequencing revealed that the strain formed a monophyletic clade with the closely related type strains of Clostridium cluster I and was most closely related to Clostridium amylolyticum JCM 14823(T) (94.38%). The temperature, pH, and NaCl range for growth was determined to be 20-45 °C (optimum 37 °C), 4.0-10.0 (optimum pH 7.3), and 0-3.0% (w/v), respectively. The strain was able to tolerate up to 7.5 % (v/v) ethanol. Yeast extract or peptone was found to be required for growth. Acids were found to be produced from glucose, mannose and trehalose. The major end products from glucose fermentation were identified as ethanol, acetate and hydrogen. The polar lipids were found to consist of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and unidentified phospholipids and polar lipids. The major fatty acids (>5%) were identified as iso-C(15:0), C(16:0), C(16:0)dma, C(14:0), anteiso-C(15:0) and iso-C(13:0). No respiratory quinone was detected. The diamino acid in the cell wall peptidoglycan was identified as meso-diaminopimelic acid and the whole-cell sugars were found to include galactose and glucose as major components. The DNA G+C content was determined to be 36.4 mol%. Based on the phylogenetic, chemotaxonomic and phenotypic evidence, the isolate is considered to represent a novel species of the genus Clostridium for which the name Clostridium swellfunianum sp. nov. is proposed. The type strain is S11-3-10(T) (=DSM 27788(T) = JCM 19606(T) = CICC 10730(T)).

Anharmonic Rice-Ramsperger-Kassel-Marcus (RRKM) and product branching ratio calculations for the partially deuterated protonated water dimers: dissociation and isomerization.

Partially deuterated protonated water dimers, H2O·H(+)·D2O, H2O·D(+)·HDO, and HDO·H(+)·HDO, as important intermediates of isotopic labeled reaction of H3O(+) + D2O, undergo direct dissociation and indirect dissociation, i.e., isomerization before the dissociation. With Rice-Ramsperger-Kassel-Marcus theory and ab initio calculations, we have computed their dissociation and isomerization rate constants separately under the harmonic and anharmonic oscillator models. On the basis of the dissociation and isomerization rate constants, branching ratios of two primary products, [HD2O(+)]∕[H2DO(+)], are predicted under various kinetics models with the harmonic or anharmonic approximation included. The feasible kinetics model accounting for experimental results is shown to include anharmonic effect in describing dissociation, while adopting harmonic approximation for isomerization. Thus, the anharmonic effect is found to play important roles affecting the dissociation reaction, while isomerization rates are shown to be insensitive to whether the anharmonic or harmonic oscillator model is being applied.

A heterogeneous Pd-Bi/C catalyst in the synthesis of L-lyxose and L-ribose from naturally occurring D-sugars.

A critical step in the synthesis of the rare sugars, L-lyxose and L-ribose, from the corresponding D-sugars is the oxidation to the lactone. Instead of conventional oxidizing agents like bromine or pyridinium dichromate, it was found that a heterogeneous catalyst, Pd-Bi/C, could be used for the direct oxidation with molecular oxygen. The composition of the catalyst was optimized and the best results were obtained with 5 : 1 atomic ratio of Pd : Bi. The overall yields of the five-step procedure to L-ribose and L-lyxose were 47% and 50%, respectively. The synthetic procedure is advantageous from the viewpoint of overall yield, reduced number of steps, and mild reaction conditions. Furthermore, the heterogeneous oxidation catalyst can be easily separated from the reaction mixture and reused with no loss of activity.

Ion-pair dissociation dynamics of SO(2) in the photon energy range 14.87-15.15 eV.

The ion-pair dissociation dynamics of SO(2) → SO(+) (X(2)Π,υ) + O(-) ((2)P(J)) in the excitation energy range 14.87-15.15 eV has been studied using the tunable XUV laser and velocity map imaging method. The O(-) yield spectrum, the translational energy distributions, and the angular distributions of the photofragments have been measured. The electronic structures and selected cuts of potential energy surfaces for the ion-pair states have been calculated by employing the quantum chemistry calculation method at the CASSCF/6-311++g** level. The equilibrium structures of the six ion-pair states all have linear geometries. An orbital correlation diagram was drawn to illustrate the ion-pair dissociation mechanism. Combining the experimental and theoretical results, it is concluded that the ion-pair dissociation takes place mainly via the predissociation of Rydberg states (1)A(1) [(C(2)B(1))4db(1)] and (1)A(1) [(D(2)A(1))4sa(1)]. The experimental results confirm the previous theoretical calculation results about the symmetry assignments for the energy sequence of SO(2)(+) as C((2)B(1)) < D((2)A(1)).

Anharmonic RRKM calculation for the dissociation of (H(2)O)(2)H(+) and its deuterated species (D(2)O)(2)D(+).

Investigations on the dissociation kinetics of hydrated protonium ions, (H(2)O)(2)H(+) and their deuterated species (D(2)O)(2)D(+), are reported based on the harmonic and anharmonic oscillator model using the transition state theory and ab initio calculations. We find that the dissociation of (H(2)O)(2)H(+) and (D(2)O)(2)D(+) exhibits a distinct threshold behavior due to the existence of activation energies. Moreover, the deviation between the harmonic and anharmonic dissociation rate constants becomes larger in the high energy or temperature range, with the rate constants becoming unreasonably large under the harmonic oscillator model. The isotope effect is found to become more distinct but only in the case of the anharmonic oscillator model. These results show that the anharmonic Rice-Ramsperger-Kassel-Marcus (RRKM) theory can provide a reasonably good description for the dissociation of (H(2)O)(2)H(+) and (D(2)O)(2)D(+). Furthermore, a theoretical model to demonstrate the principle of vibrational predissociation spectroscopy (VPS) is established from the viewpoint of RRKM theory and applied in determining the experimental conditions and understanding the role of the dissociation rate constant k(E) played in the VPS experiment, using (H(2)O)(2)H(+) and (D(2)O)(2)D(+) as examples.

Ion-pair dissociation dynamics of HCl: fast predissociation.

We have studied the ion-pair dissociation dynamics of HCl --> Cl(-) ((1)S(0)) + H(+) in the 14.41-14.60 eV using tunable XUV laser and the velocity map imaging method. The measured ion-pair yield spectrum has P- and R-branch resolved vibrational structure, which indicates a predissociation mechanism for the ion-pair dissociation. All of the anisotropy parameters for the angular distribution of the fragments have the limiting values of beta = 2, which suggests that the predissociation occurs via (1)Sigma(+) Rydberg states, and is fast in comparison with the rotational period of HCl. To understand the predissociation dynamics, the diabatic potential energy curve of the ion-pair state has been calculated at the MRCI/CAS/vtz level. The experimental and theoretical results obtained in this work have provided a solid foundation for the previously proposed mechanism that the ion-pair dissociation occurs via predissociation of Rydberg states converging to HCl(+) (A(2)Sigma(+)).

The relationship between C reactive protein and clinical stage in nasopharyngeal carcinoma / 中国癌症杂志

Background and purpose: Recent literature has high lighted an important role of inflammation in promoting cancer. CRP (C reactive protein) is a way of building the bridge between inflammation and cancer. We aimed to explore correlations between CRP levels and clinical stages of nasopharyngeal carcinoma(NPC). Methods: We analyzed 108 cases, among which 68 cases were NPC, 20 cases were benign inflammatory diseases of nasopharynx, and another 20 were healthy volunteers as control. We detected the level of CRP using immunoturbidimetry (ITM), q test was calculated by SPSS. Results: The mean concentrations of CRP in NPC[(19.8±4.7) mg/L] were significantly increased compared to those in the control group[(6.2±1.8) mg/L], while they were significantly lower than those in benign inflammatory group[(45.6±7.9) mg/L]. In NPC, The mean concentrations of CRP in T4[(25.6±3.9) mg/L] were higher than those in T1[(17.4±5.8) mg/L], T2[(18.6±8.5) mg/L] and T3[(15.6±1.8) mg/L] respectively. The mean concentrations of CRP in N3[(28.0±7.1) mg/L] were higher than those in N0[(17.6±6.8) mg/L], N1[(21.3±5.1) mg/L] and N2[(18.6±5.6) mg/L] respectively. The mean concentrations of CRP in 1V[(25.7±5.5) mg/L] were higher than those in Ⅰ[(14.2±1.9) mg/L], Ⅱ[(16.1±3.9) mg/L] and Ⅲ[(23.0±7.7) mg/L] respectively (P<0.05). There were no statistic differences between the other groups. Conclusion: The serum CRP level is associated with the occurrence of NPC and benign inflammatory disease of nasopharynx. In NPC, the higher the CRP level is, the more advanced the TNM stage will be.

Novel sensitive high-throughput screening strategy for nitrilase-producing strains.

Nitrilases have found wide use in the pharmaceutical industry for the production of fine chemicals, and it is important to have a method by which to screen libraries of isolated or engineered nitrilase variants (including bacteria and fungi). The conventional methods, such as high-performance liquid chromatography, liquid chromatography-mass spectrometry, capillary electrophoresis, or gas chromatography, are tedious and time-consuming. Therefore, a direct and sensitive readout of the nitrilase's activity has to be considered. In this paper, we report a novel time-resolved luminescent probe: o-hydroxybenzonitrile derivatives could be applied to detect the activity of the nitrilases. By the action of nitrilases, o-hydroxybenzonitrile derivatives can be transformed to the corresponding salicylic acid derivatives, which, upon binding Tb(3+), serve as a photon antenna and sensitize Tb(3+) luminescence. Because of the time-resolved property of the luminescence, the background from the other proteins (especially in the fermentation system) in the assay could be reduced and, therefore, the sensitivity was increased. Moreover, because the detection was performed on a 96- or 384-well plate, the activity of the nitrilases from microorganisms could be determined quickly. Based on this strategy, the best fermentation conditions for nitrilase-producing strains were obtained.