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A MXene-GaN-MXene based multiple quantum well photodetector was prepared on patterned sapphire substrate by facile drop casting. The use of MXene electrodes improves the responsivity and reduces dark current, compared with traditional Metal-Semiconductor-Metal (MSM) photodetectors using Cr/Au electrodes. Dark current of the device using MXene-GaN van der Waals junctions is reduced by three orders of magnitude and its noise spectral intensity shows distinct improvement compared with the traditional Cr/Au–GaN–Cr/Au MSM photodetector. The improved device performance is attributed to low-defect MXene-GaN van der Waals interfaces. Thanks to the high quality MXene-GaN interfaces, it is possible to verify that the patterned substrate can locally improve both light extraction and photocurrent collection. The measured responsivity and specific detectivity reach as high as 64.6 A/W and 1.93 × 1012 Jones, respectively, making it a potential candidate for underwater optical detection and communication. The simple fabrication of MXene-GaN-MXene photodetectors spearheaded the way to high performance photodetection by combining the advantages of emerging 2D MXene materials with the conventional III-V materials., A MXene-GaN van der Waals Metal-Semiconductor Junctions based High Performance Multiple Quantum Well Photodetector was demonstrated, which shows great potential for underwater wireless optical communication and turbidity sensing.

Current study was set to determine the impact of active smoking on Achilles Tendon (AT) as soft tissue using an elastographic technique. This study comprises of 54 male individuals having sedentary lifestyle. Volunteers were categorized into two groups of smokers (n = 20) and non-smokers (n = 34). Body composition analysis was performed to evaluate the physiological changes in human body mass indexes. Ultrasound Strain Elastog-raphy (USE) technique was used to find the stiffness along with anatomical images to envisage the anomalous status of Achilles tendon. Statistical analysis of data obtained through body composition, tendon anatomy and Strain Elastography (SE) was used to scrutinize the physiological, anatomical and elasticity variations within the tendon. A reduction in Fat Free Mass Index (FFMI) was observed among smokers with a significant difference (P = 0.042). Further, an increased significant difference (P = 0.029) was found in AT Strain Ratios (SR) of smokers as compared to non-smokers. Lightening in tendon mass and dilution in tendon stiffness indicates that smoking mechanism may generate excessive apoptosis and decrease the density of tenocytes. Nicotine is the key element that inhibits the functional capacity of Tendon Stem Cells and is highly responsible for tendinopathy, eventually leading to tendon rupture and injury.

Background This study aimed to investigate the relationship between stiffness of the bicep brachii muscle (BBM) and distal bicep tendon (DBT) and effects of weight lifting (pre- to post-workout changes) among groups with different body mass indexes (BMI). Methods Participants were divided into four groups according to BMI: A, underweight (2); B, normal (18.5–24.9 kg/m2); C, overweight (25.0–29.9 kg/m2); and D, obese (> 30.0 kg/m2). All participants were males who were untrained and had sedentary lifestyle without involvement in sports activities for the past 12 months. Ultrasonographic measurements to determine muscle and tendon stiffness was performed on the dominant side (i.e., right side) of the upper extremities in all participants. Results Twenty-one healthy and untrained males volunteered to participate in this study; 14 were nonsmokers and 7 were smokers. The mean age and BMI were 22.5 ± 1.5 years and 23.8 ± 6.3 kg/m2, respectively. Groups A, B, C, and D had four, ten, four, and three participants, respectively. The BBM thickness did not increase with increase in BMI and was not significantly different (P > .05) between groups. The BBM stiffness was significantly different (all P Conclusions Our study revealed that the BBM thickness is independent of BMI. After weight lifting, BBM stiffness in groups A and B increased for BBM compared to those in groups C and D. A similar trend was also recorded for DBT. Weight lifting in concentric and eccentric motions affects the stiffness of the BBM and DBT, thus weight lifting plays a role in adjusting the stiffness of the BBM and DBT. Trial registration The study was approved by ethics committee of the College of Applied Medical Sciences (CAMS 080-3839; March 14, 2018).

This study aimed to determine the difference in stiffness and thickness of finger tendons between individuals who performed weight lifting (trained subjects) and those who did not perform weightlifting (untrained subjects) as well as provide real-time diagnosis of tendon stiffness. The study was divided into two groups according to their physical activity level. Individuals who performed training for their upper body for a minimum of 30 minutes, 5 days a week for at least 6 months were categorized as trained individuals, whereas those who did not train were categorized as untrained individuals. Tendon strain ratio and thickness of the index and middle fingers and body mass index (BMI) of trained and untrained adult males were measured. A total of 20 healthy individuals were enrolled for the study. Untrained individuals tended to have higher strain ratios than trained individuals. Tendon thickness between the groups was slightly different. Increased BMI was found in untrained individuals. Trained individuals had stiffer finger tendons than untrained individuals. Different activities, sedentary lifestyles or lifting weight can substantially affect the properties and size of the tendon, which can lead to strengthening or weakening of the finger tendon.

Multifunctional thin films which can display both photocatalytic and antibacterial activity are of great interest industrially. Here, for the first time, we have used aerosol assisted chemical vapour deposition (AACVD) to deposit highly photoactive thin films of Cu-doped anatase TiO2 on glass substrates. The films displayed much enhanced photocatalytic activity relative to pure anatase, and showed excellent antibacterial (vs S.Aureus and E.Coli) ability. Using a combination of transient absorption spectroscopy (TAS), photoluminescence (PL) measurements and hybrid density functional theory calculations, we have gained nanoscopic insights into the improved properties of the Cu-doped TiO2 films. Our analysis has highlighted that the interactions between substitutional and interstitial Cu in the anatase lattice can explain the extended exciton lifetimes observed in the doped samples, and the enhanced UV/visible light photoactivities observed.

Photoelectrochemical production of hydrogen by using sunlight to split water offers a sustainable approach for clean energy generation. III-V semiconductors have shown the highest efficiencies for photoelectrochemical water splitting but the prohibitive cost of commercial single-crystalline GaP wafers limit practical use and large-scale application. Here, we report a high-quality GaP photocathode directly grown on a silicon substrate by solid-source molecular beam epitaxy. The photocathode can be stabilized under acidic electrolyte 1 M HClO 4 (pH 0) by combining an amorphous TiO 2 layer coated with a molybdenum sulphide MoS 2 hydrogen evolution catalyst by atomic layer deposition (ALD). Under simulated AM 1.5G solar illumination, the Si/GaP photocathode yielded a maximum photocurrent density of 0.95 (mA cm -2 ) with a proton reduction onset potential of 467 mV versus the reversible hydrogen electrode. The average faradaic efficiency of the Si/GaP photocathode was measured to be over 73.4 ± 20.2% for over 100 minutes. The photoelectrochemical studies for the Si/GaP photocathode show the potential for widespread deployment of cost-effective photoelectrodes for hydrogen generation.

OBJECTIVES The aim of this study was to establish a relationship between quadriceps tendon stiffness and its properties and variations in the body mass index (BMI) and segmental mass. METHODS This study was conducted in 3 groups according to their BMI (A, low [ 25.0 kg/m2 ]). All of the participants included had a sedentary lifestyle and did not do any weightlifting or any kind of sports activity in the previous 6 months. Ultrasound measurements were performed on the participants' lower right extremities, since it was the dominant side for all of the participants. RESULTS A total of 40 healthy untrained men participated in the study. The mean age of the participants ± SD was 22.1 ± 1.3 years; the age ranges for groups A (n = 6), B (n = 18), and C (n = 16) were 19-23, 19-25, and 20-25 years, respectively; 28 of the participants were nonsmokers, and 12 of were smokers. A strong statistical difference (all P

Human body measurement data related to walking can characterize functional movement and thereby become an important tool for health assessment. Single-camera-captured two-dimensional (2D) image sequences of marker-less walking individuals might be a simple approach for estimating human body measurement data which could be used in walking speed-related health assessment. Conventional body measurement data of 2D images are dependent on body-worn garments (used as segmental markers) and are susceptible to changes in the distance between the participant and camera in indoor and outdoor settings. In this study, we propose five ratio-based body measurement data that can be extracted from 2D images and can be used to classify three walking speeds (i.e., slow, normal, and fast) using a deep learning-based bidirectional long short-term memory classification model. The results showed that average classification accuracies of 88.08% and 79.18% could be achieved in indoor and outdoor environments, respectively. Additionally, the proposed ratio-based body measurement data are independent of body-worn garments and not susceptible to changes in the distance between the walking individual and camera. As a simple but efficient technique, the proposed walking speed classification has great potential to be employed in clinics and aged care homes.

International audience; Here, the structural, electronic and optical properties of the GaP 1-x Sb x /Si tandem materials association are determined in view of its use for solar water splitting applications. The GaPSb crystalline layer is grown on Si by Molecular Beam Epitaxy with different Sb contents. The bandgap value and bandgap type of GaPSb alloy are determined on the whole Sb range, by combining experimental absorption measurements with tight binding (TB) theoretical calculations. The indirect (X-band) to direct (Γ-band) cross-over is found to occur at 30% Sb content. Especially, at a Sb content of 32%, the GaP 1-x Sb x alloy reaches the desired 1.7eV direct bandgap, enabling efficient sunlight absorption, that can be ideally combined with the Si 1.1 eV bandgap. Moreover, the band alignment of GaP 1-x Sb x alloys and Si with respect to water redox potential levels has been analyzed, which shows the GaPSb/Si association is an interesting combination both for the hydrogen evolution and oxygen evolution reactions. These results open new routes for the development of III-V/Si low-cost high-efficiency photoelectrochemical cells.

Photoelectrochemical (PEC) water splitting is a promising clean route to hydrogen fuel. The best-performing materials (III/V semiconductors) require surface passivation, as they are liable to corrosion, and a surface co-catalyst to facilitate water splitting. At present, optimal design combining photoelectrodes with oxygen evolution catalysts remains a significant materials challenge. Here, we demonstrate that nickel-coated amorphous three-dimensional (3D) TiO(2)core-shell nanorods on a TiO(2)thin film function as an efficient hole-extraction layer and serve as a protection layer for the GaAs photoanode. Transient-absorption spectroscopy (TAS) demonstrated the role of nickel-coated (3D) TiO(2)core-shell nanorods in prolonging photogenerated charge lifetimes in GaAs, resulting in a higher catalytic activity. This strategy may open the potential of utilizing this low-cost (3D) nanostructured catalyst for decorating narrow-band-gap semiconductor photoanodes for PEC water splitting devices.

Photoelectrochemical (PEC) water splitting is a promising clean route to hydrogen fuel. The best-performing materials (III/V semiconductors) require surface passivation, as they are liable to corrosion, and a surface co-catalyst to facilitate water splitting. At present, optimal design combining photoelectrodes with oxygen evolution catalysts remains a significant materials challenge. Here, we demonstrate that nickel-coated amorphous three-dimensional (3D) TiO

This paper aimed to classify two forearm muscles known as Flexor Carpi Ulnaris (FCU) and Extensor Carpi Radialis Longus (ECRL) using surface Electromyography (sEMG) signal during different hand prehension tasks, such as cylindrical, tip, spherical, palmar, lateral and hook while grasping any object. Thirteen Machine Learning (ML) algorithms were analyzed to compare their performance using a single EMG time domain feature called integrated EMG (IEMG). The tree-based methods have the top performance to classify the forearm muscles than other ML methods among all those 13 ML algorithms. Results showed that 4 out of 5 tree-based classifiers achieved more than 75% accuracies, where the random forest method showed maximum classification accuracy (85.07%). Additionally, these tree-based ML methods computed the variable importance in classification margin. The results showed that the lateral grasping was the most important moving variable for all those algorithms except AdaBoost where tipping was the most significant movement variable for this method. We hope, this ML- and EMG-based classification results presented in the paper may alleviate some of the problems in implementing advanced forearm prosthetics, rehabilitation devices and assistive biomedical robots.

This study aimed to investigate the electrical activity of two muscles located at the dorsal surface during Islamic prayer (Salat). Specifically, the electromyography (EMG) activity of the erector spinae and trapezius muscles during four positions observed while performing Salat, namely standing, bowing, sitting and prostration, were investigated. Seven adult subjects with an average age of 28.1 (± 3.8) years were included in the study. EMG data were obtained from their trapezius and erector spinae muscles while the subjects maintained the specific positions of Salat. The EMG signal was analysed using time and frequency domain features. The results indicate that the trapezius muscle remains relaxed during the standing and sitting positions while the erector spinae muscle remains contracted during these two positions. Additionally, during the bowing and prostration positions of Salat, these two muscles exhibit the opposite activities: the trapezius muscle remains contracted while the erector spinae muscle remains relaxed. Overall, both muscles maintain a balance in terms of contraction and relaxation during bowing and prostration position. The irregularity of the neuro-muscular signal might cause pain and prevent Muslims from performing their obligatory prayer. This study will aid the accurate understanding of how the back muscles respond in specific postures during Salat.

Indium gallium nitride (InGaN) is an attractive semiconductor, with a tunable direct bandgap for photoelectrochemical water splitting, but it corrodes in aqueous electrolytes. Cobalt oxide (CoOx) is a promising cocatalyst to protect photoelectrodes and accelerate the charge transfer. CoOx is earth-abundant and stable in extremely alkaline conditions and shows high activity for the oxygen evolution reaction (OER). In this work, we demonstrate that CoOx directly deposited onto InGaN/GaN multiple quantum well photoanodes exhibits excellent activity and stability in a strong alkaline electrolyte, 1 M NaOH (pH = 13.7), for water oxidation up to 28 h, while a reference sample without the catalyst degraded rapidly in the alkaline electrolyte. Under simulated solar illumination, the CoOx-modified InGaN/GaN quantum well photoanode showed a high photocurrent density of 1.26 mA cm–2 at 1.23 V and an onset potential of −0.03 V versus a reversible hydrogen electrode.

International audience; Hydrogen produced using artificial photosynthesis, i.e. solar splitting of water, is a promising energy alternative to fossil fuels. Efficient solar water splitting demands a suitable band gap to absorb near full spectrum solar energy and a photoelectrode that is stable in strongly alkaline or acidic electrolytes. In this work, we demonstrate for the first time, a perfectly relaxed GaP0.67Sb0.33 monocrystalline alloy grown on a silicon substrate with a direct band gap of 1.65 eV by molecular beam epitaxy (MBE) without any evidence of chemical disorder. Under one Sun illumination, the GaP0.67Sb0.33 photoanode with a 20 nm TiO2 protective layer and 8 nm Ni co-catalyst layer shows a photocurrent density of 4.82 mA cm−2 at 1.23 V and an onset potential of 0.35 V versus the reversible hydrogen electrode (RHE) in 1.0 M KOH (pH = 14) aqueous solution. The photoanode yields an incident-photon-to-current efficiency (IPCE) of 67.1% over the visible range between wavelengths 400 nm to 650 nm. Moreover, the GaP0.67Sb0.33 photoanode was stable over 5 h without degradation of the photocurrent under strong alkaline conditions under continuous illumination at 1 V versus RHE. Importantly, the direct integration of the 1.65 eV GaP0.67 Sb0.33 on 1.1 eV silicon may pave the way for an ideal tandem photoelectrochemical system with a theoretical solar to hydrogen efficiency of 27%.

The initial identification of breast cancer and the prediction of its category have become a requirement in cancer research because they can simplify the subsequent clinical management of patients. The application of artificial intelligence techniques (e.g., machine learning and deep learning) in medical science is becoming increasingly important for intelligently transforming all available information into valuable knowledge. Therefore, we aimed to classify six classes of freshly excised tissues from a set of electrical impedance measurement variables using five ensemble-based machine learning (ML) algorithms, namely, the random forest (RF), extremely randomized trees (ERT), decision tree (DT), gradient boosting tree (GBT) and AdaBoost (Adaptive Boosting) (ADB) algorithms, which can be subcategorized as bagging and boosting methods. In addition, the ranked order of the variables based on their importance differed across the ML algorithms. The results demonstrated that the three bagging ensemble ML algorithms, namely, RF ERT and DT, yielded better classification accuracies (78–86%) compared with the two boosting algorithms, GBT and ADB (60–75%). We hope that these our results would help improve the classification of breast tissue to allow the early prediction of cancer susceptibility.

The purpose of this study is to analyze the values of the stiffness of different segments (proximal, distal and medial) of patellar tendon with respect to Hoffa Fat Pad, which will postulate to the framework in understanding the area bearing more force (stress) for the patellar tendon. It can help in understanding and avoiding the patellar tendon rupture or tendinopathy. Three volunteers were selected for the current study and were classified into three arrangements (weak, normal and obese) according to their Body Mass Index. The first volunteer (A; weak) was having BMI of 16 kg/m2, the second volunteer (B; normal) was having BMI of 22 kg/m2 and the third volunteer (C; obese) was having BMI of 27 kg/m2. All participants were reported to be non-smokers with mean BMI ± SD and mean age ± SD, $21.61 \pm 5.508$ Kg/m2 and $26 \pm 3$ years, respectively. Patellar tendon length and strain ratios reading were performed on the dominant side of each volunteer. All the three segments (proximal, medial and distal) of patellar tendon showed presence of significant difference for most of the readings between the three volunteers, however, a significant difference in length is present for every volunteer. Our findings suggest that strain value at a particular region of a tendon are independent values irrespective of weight, body mass index and physical activity. Though, more research and further studies are required to validate the independence of strain value at a particular region of the patellar tendon.

The purpose of this study was to compare diagnostic values of normal and effected tissues with two techniques using strain elastography and tissues characterization. This study was carried out on a breast phantom containing all human body parameters. Analysis was performed using a lone phantom to correlate a relation between the values of Strain Elastography (SE) and first order texture parameters results. For SE SonixTouch Q+ (Ultrasonix Medical Corporation, 130-4311 Viking Way, Richmond, Canada) device using a linear-array ultrasound probe at a frequency of 10MHz with a gain of 40%. Elastography breast phantom was purchased from CAE healthcare USA, 3600 Edgelake Drive Sarasota FL, USA. For tissue characterization a Region of Interest (ROI) that encompasses both (normal and stiffer) areas were selected. MAZDA software was used to carry out the image analysis (mean and variance) of the tumour and healthy tissue, ROI of 1600 pixels at both regions was selected. An affirmative and resilient outcome was observed between the numerals of normal and tumor tissues, both for SE and first order texture parameters values. After our study we suggest that SE and tissue characterisation via first order texture parameter is a reliable technique to highlight normal and tumor tissue (with respect to same reference, for SE technique only). SE and first order texture parameters (mean and variance) paved way in highlighting the breast tumors fully. It is suggested that SE being more reliable approach in determining the stiffness for breast lesion, as it produces the results with real time imaging. However texture parameter gives an objective assessment of the image with a discriminating feature of the tissue.

Thyroid nodules are benign though suspicious. Examination through elastography technique is beneficial as it provides real time and first hand evidence about the tissue stiffness by providing a strain value on comparing suspected and normal tissue. Until now, there is no established method that allows to categorise strain ratios whether tumour or normal. Changes in gain settings can significantly alter measurement and ultimately the clinical findings. The objectives of this study are to assess the effect of gain settings on strain ratios of isoechoic stiff lesions in a thyroid gland phantom, and the difference in strain ratios with first order texture parameters at different gain settings. In this study we have reported the effect of gain setting parameter on strain ratios of the thyroid tumour. Furthermore, first order texture parameters (mean and variance) were discussed with respect to increase in gain settings. Higher strain ratios were observed as gain increased. Significant differences in first order texture parameters can be observed for mean of tumour when compared with normal thyroid tissue. Variance did not demonstrate any significant difference. It was concluded that gain parameter effect the strain ratios and texture parameters. This may affect the interpretation of results. It is advised to use elastography in combination with B-mode ultrasound, and sonographers must use a balanced approach when changing equipment parameters.

Diabetic neuropathy is one of the physical complications of diabetes mellitus (DM) patients with a long history of diabetes. An electromyography (EMG)-based assessment may be very useful for the management of diabetic neuropathy. In the present study, we aimed to summarize all of the findings and recommendations obtained from previous studies that investigated the application of EMG to the assessment of diabetic neuropathy. An extensive search of the prominent electronic databases PubMed, Google Scholar and Scopus was performed to evaluate the following areas: (i) what are the muscles to be evaluated by EMG for neuropathy assessment, (ii) what type of EMG methodologies have been used and (iii) what recommendation can be made for neuropathy detection. The major findings are summarized as follows: (i) very few studies have analyzed the correlation of the EMG signals acquired from peripheral muscles affected in neuropathy with those obtained with non-neuropathic complications, such as ankle sprain; (ii) EMG has been applied for the detection of diabetic neuropathy more than diabetes treatment; and (iii) neuropathy detection using an EMG-based assessment were mainly performed for type 2 DM patients aged at least 50 years.

The Achilles tendon have two major problems due to injury; one being a chronic injury called Achilles tendinopathy and the second being acute injury which are more commonly known as Achilles tendon rupture. Changes in stiffness of Achilles tendon is alarming and can cause deleterious effects on quality of life in an individual. Achilles tendon is reported to be affected significantly due to the weight of an individual. The effect of Body Mass Index (BMI) on stiffness of Achilles tendon was evaluated in the current study. Elastography was performed on individuals ranging from 19 to 23 years for detecting the stiffness of the Achilles tendon. Individuals were grouped according to their BMI in 3 categories (underweight, normal and overweight) and their strain ratios were measured. The strain ratio results for all volunteers were ranging from 1.03 to 6 (1.03 for underweight and 6 for overweight). Difference in weight of individuals effect the Achilles tendon stiffness. The overweight individuals had the highest stiffness while the underweight individuals had the lowest. It is concluded that higher stiffness may likely lead to Achilles tendon injury.

Studies of the surface electromyographic or EMG signal on the skeletal muscles have provided valuable information on the physiology to understand the motor unit activity strategy during contraction. This paper investigated the relationship between EMG and time during isokinetic contraction (a type of exercises or movement to increase muscular strength) from the upper limb’s biceps brachii (BB) muscle. Five right-hand-dominated male subjects (age 23.2 ± 1.6 years) participated in the study. The muscle activation during load lifting (using a standard 6-kg dumbbell) was determined as the root mean square (RMS) electromyographic signal normalized to the peak RMS EMG signal of a maximal contraction for 10 s. For the statistical analysis, the slope of the regression relationship was used to test the relationships between EMG and time from the maximal voluntary isokinetic contraction (MVC). The measurement duration (10 s) was divided into four phases for analyzing the relationship. The results of the study showed a linear but poor relationship between EMG and time during such contraction, where r 2 = 0.11 and F = 3.74. Also, no significant difference exits from the analysis where, P = 0.062. These results provided insight toward applications of biomedical engineering methods in the analysis and control of the neuromuscular system, ergonomics field of research, rehabilitation engineering, and movement biomechanics during such type of dynamic contraction.

Photodetectors, which can convert light signals into electrical signals, are important opto‐electronic devices in imaging, optical communication, biomedical/biological sensing, and so on. Here a solution‐processed photodetector based on the triple cation perovskite is demonstrated. The perovskite photodetectors show a high detectivity, high speed, as well as excellent environmental stability. Operating at a low voltage bias of 2 V, the photodetectors exhibit a large on/off ratio of 105, high specific detectivity of ≈1013 Jones, and a fast photoresponse with 3 dB bandwidth up to 0.82 MHz. Further analysis demonstrates that such performance originates from the modulated Schottky barrier height by illumination. The barrier suppresses dark current without any illumination, but it can be effectively lowered under illumination, thus resulting in a more efficient charge extraction and collection. The results demonstrate a great potential of triple cation perovskite in photodetection and provide a route to achieve high performance devices.

This study examined the effects of electromyographic (EMG) signals from Biceps Brachii (BB) muscle on the root mean square (RMS)-time relationships during dynamic contraction. Ten healthy and right hand dominated male subjects were volunteered for the experiments. The RMS features were extracted from the corresponding EMG signals (amplitude of the full wave EMG) for 10 seconds in 5 minutes intervals between each trial. Ten seconds (or 10000 ms) were divided into 4 time lags to identify the muscle activity and relationship between EMG and time using different statistical analysing techniques, such as mean, regression analysis, correlation, ANOVA, and coefficient of variation (CoV) for muscle activity variation. The results shows that large positive linear association between EMG and endurance time where the points are close to the linear trend line (R squared = 0.93 and F-ratio = 453.1). Signal steadiness is better during last time lags (1.66% during 7501–10000 ms) compared to initial time duration (10.35% during 0–2500 ms).

A lump in breast may suggest a possible development of breast cancer. As the tumor develops, it changes the physical property of the tissue by changing its stiffness. To detect the tumor generally mammography is performed. The findings of mammography are often inaccurate as it does not take into account the stiffness of tissue. Elastography is an imaging technique to measure the stiffness of tissues. In the current study, we have used a breast phantom to analyze differences between a tumor and a cyst via comparing shear-wave elastography and strain elastography techniques. Both the techniques performed equally for the diagnosis of tumour. However, it is suggested that strain elastography must be used in the diagnosis of a cyst as it provides enhanced details of the surrounding tissues.

The relationship between surface electromyography (EMG) and force have been the subject of ongoing investigations and remain a subject of controversy. Even under static conditions, the relationships at different sensor placement locations in the biceps brachii (BB) muscle are complex.The aim of this study was to compare the activity and relationship between surface EMG and static force from the BB muscle in terms of three sensor placement locations.Twenty-one right hand dominant male subjects (age 25.3 ± 1.2 years) participated in the study. Surface EMG signals were detected from the subject's right BB muscle. The muscle activation during force was determined as the root mean square (RMS) electromyographic signal normalized to the peak RMS EMG signal of isometric contraction for 10 s. The statistical analysis included linear regression to examine the relationship between EMG amplitude and force of contraction [40-100% of maximal voluntary contraction (MVC)], repeated measures ANOVA to assess differences among the sensor placement locations, and coefficient of variation (CoV) for muscle activity variation.The results demonstrated that when the sensor was placed on the muscle belly, the linear slope coefficient was significantly greater for EMG versus force testing (formular^{2}/formula= 0.61, P0.05) than when placed on the lower part (formular^{2}/formula=0.31, P0.05) and upper part of the muscle belly (formular^{2}/formula=0.29, P0.05). In addition, the EMG signal activity on the muscle belly had less variability than the upper and lower parts (8.55% vs. 15.12% and 12.86%, respectively).These findings indicate the importance of applying the surface EMG sensor at the appropriate locations that follow muscle fiber orientation of the BB muscle during static contraction. As a result, EMG signals of three different placements may help to understand the difference in the amplitude of the signals due to placement.

[Purpose] This study investigated the changes in the slope of EMG-time curves (relationship) at the maximal and different levels of dynamic (eccentric and concentric) and static (isometric) contractions. [Subjects and Methods] The subject was a 17 year-old male adolescent. The surface EMG signal of the dominant arm's biceps brachii (BB) was recorded through electrodes placed on the muscle belly. [Results] The results obtained during the contractions show that the regression slope was very close to 1.00 during concentric contraction, whereas those of eccentric and isometric contractions were lower. Significant differences were found for the EMG amplitude and time lags among the contractions. [Conclusion] The results show that the EMG signal of the BB varies among the three modes of contraction and the relationship of the EMG amplitude with a time lag gives the best fit during concentric contraction.

The aim of this study was to investigate whether there are differences in the amplitude of the EMG signal among five different age groups of adolescent's muscle. Fifteen healthy adolescents participated in this study and they were divided into five age groups (13, 14, 15, 16 and 17 years). Subjects were performed dynamic contraction during lifting a standard weight (3-kg dumbbell) and EMG signals were recorded from their Biceps Brachii (BB) muscle. Two common EMG analysis techniques namely root mean square (RMS) and mean absolute values (MAV) were used to find the differences. The statistical analysis was included: linear regression to examine the relationships between EMG amplitude and age, repeated measures ANOVA to assess differences among the variables, and finally Coefficient of Variation (CoV) for signal steadiness among the groups of subjects during contraction. The result from RMS and MAV analysis shows that the 17-years age groups exhibited higher activity (0.28 and 0.19 mV respectively) compare to other groups (13-Years: 0.26 and 0.17 mV, 14-years: 0.25 and 0.23 mV, 15-Years: 0.23 and 0.16 mV, 16-years: 0.23 and 0.16 mV respectively). Also, this study shows modest correlation between age and signal activities among all age group's muscle. The experiential results can play a pivotal role for developing EMG prosthetic hand controller, neuromuscular system, EMG based rehabilitation aid and movement biomechanics, which may help to separate age groups among the adolescents.