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With the increasing use of radar technology across various fields, electromagnetic pollution has become a growing concern, posing significant risks to human health. Consequently, there is a rising interest in developing wearable, flexible fabric-based absorbers that can efficiently absorb electromagnetic waves. However, the low dielectric constant of fabrics makes it challenging to achieve high absorption rates and broad bandwidth at low frequencies. To address this issue, in this study, we introduce a fabric-based broadband metamaterial absorber using felt as the dielectric substrate. The absorber features a centrosymmetric square block array design, incorporating a PU conductive film as the surface resonant material. By fine-tuning the parameters of each component in the absorber's equivalent circuit and optimizing structural parameters, the absorber achieves an extended bandwidth from 3.92 to 15.25 GHz, with a relative absorption bandwidth of 118.21%. Impressively, in the lower frequency C-band, the absorber maintains an efficiency of over 95%. The absorber was fabricated using the "cut-transfer-paste patterning method." Testing results demonstrate that it is insensitive to incident angle and polarization and retains excellent absorption performance even when being bent. [ABSTRACT FROM AUTHOR]

Cotton is an important natural fiber crop; its seeds are the main oil source. Abiotic stresses cause a significant decline in its production. The WUSCHEL-related Homeobox (WOX) genes have been involved in plant growth, development, and stress responses. However, the functions of WOX genes are less known in cotton. This study identified 39, 40, 21, and 20 WOX genes in Gossypium hirsutum, Gossypium barbadense, Gossypium arboreum, and Gossypium raimondii, respectively. All the WOX genes in four cotton species could be classified into three clades, which is consistent with previous research. The gene structure and conserveddomainof allWOXgeneswere analyzed. The expressions ofWOX genes in germinating hypocotyls and callus were characterized, and it was found that most genes were up-regulated. One candidate gene Gh_ A01G127500 was selected to perform the virus-induced gene silencing (VIGS) experiment, and it was found that the growth of the silenced plant (pCLCrVA: GhWOX4_A01) was significantly inhibited compared with the wild type. In the silenced plant, there is an increase in antioxidant activities and a decrease in oxidant activities compared with the control plant. In physiological analysis, the relative electrolyte leakage level and the excised leaf water loss of the infected plant were increased. Still, both the relative leaf water content and the chlorophyll content were decreased. This study proved that WOX genes play important roles in drought stress and callus induction, but more work must be performed to address the molecular functions of WOX genes. [ABSTRACT FROM AUTHOR]

Background: Cotton production is adversely effected by drought stress. It is exposed to drought stress at various critical growth stages grown under a water scarcity environment. Roots are the sensors of plants; they detect osmotic stress under drought stress and play an important role in plant drought tolerance mechanisms. The seedling stage is very sensitive to drought stress, and it needed to explore the methods and plant characteristics that contribute to drought tolerance in cotton. Results: Initially, seedlings of 18 genotypes from three Gossypium species: G. hirsutum, G. barbadense, and G. arboreum, were evaluated for various seedling traits under control (NS) and drought stress (DS). Afterward, six genotypes, including two of each species, one tolerant and one susceptible, were identified based on the cumulative drought sensitivity response index (CDSRI). Finally, growth rates (GR) were examined for shoot and root growth parameters under control and DS in experimental hydroponic conditions. A significant variation of drought stress responses was observed across tested genotypes and species. CDSRI allowed here to identify the drought-sensitive and drought-resistant cultivar of each investigated species. Association among root and shoots growth traits disclosed influential effects of enduring the growth under DS. The traits including root length, volume, and root number were the best indicators with significantly higher differential responses in the tolerant genotypes. These root growth traits, coupled with the accumulation of photosynthates and proline, were also the key indicators of the resistance to drought stress. Conclusion: Tolerant genotypes have advanced growth rates and the capacity to cop with drought stress by encouraging characteristics, including root differential growth traits coupled with physiological traits such as chlorophyll and proline contents. Tolerant and elite genotypes of G. hirsutum were more tolerant of drought stress than obsolete genotypes of G. barbadense and G. arboreum. Identified genotypes have a strong genetic basis of drought tolerance, which can be used in cotton breeding programs. [ABSTRACT FROM AUTHOR]

Background: Cotton production is adversely effected by drought stress. It is exposed to drought stress at various critical growth stages grown under a water scarcity environment. Roots are the sensors of plants; they detect osmotic stress under drought stress and play an important role in plant drought tolerance mechanisms. The seedling stage is very sensitive to drought stress, and it needed to explore the methods and plant characteristics that contribute to drought tolerance in cotton. Results: Initially, seedlings of 18 genotypes from three Gossypium species: G. hirsutum, G. barbadense, and G. arboreum, were evaluated for various seedling traits under control (NS) and drought stress (DS). Afterward, six genotypes, including two of each species, one tolerant and one susceptible, were identified based on the cumulative drought sensitivity response index (CDSRI). Finally, growth rates (GR) were examined for shoot and root growth parameters under control and DS in experimental hydroponic conditions. A significant variation of drought stress responses was observed across tested genotypes and species. CDSRI allowed here to identify the drought-sensitive and drought-resistant cultivar of each investigated species. Association among root and shoots growth traits disclosed influential effects of enduring the growth under DS. The traits including root length, volume, and root number were the best indicators with significantly higher differential responses in the tolerant genotypes. These root growth traits, coupled with the accumulation of photosynthates and proline, were also the key indicators of the resistance to drought stress. Conclusion: Tolerant genotypes have advanced growth rates and the capacity to cop with drought stress by encouraging characteristics, including root differential growth traits coupled with physiological traits such as chlorophyll and proline contents. Tolerant and elite genotypes of G. hirsutum were more tolerant of drought stress than obsolete genotypes of G. barbadense and G. arboreum. Identified genotypes have a strong genetic basis of drought tolerance, which can be used in cotton breeding programs. [ABSTRACT FROM AUTHOR]

Meiyu front precipitation makes the region prone to frequent floods, mudslides, landslides, and other disasters and has been the focus of ongoing and challenging meteorological research. Investigation of the Raindrop size distribution (RSD) is essential for exploring the characteristics and underlying physical precipitation processes. In this study, the precipitation characteristics in Lushan mountainous areas during the Meiyu season were investigated using laser disdrometer observed RSD data from 2016 to 2020. For the average spectra of five rain rate classes, the concentrations of large raindrops (> 0.5 mm) increased with rain rate (R), whereas the concentrations of small raindrops (< 0.5 mm) increased only under rain rates higher than 10 mm h-1. The gamma distribution parameters of N0 (intercept parameter) and Λ (slope parameter) increased/decreased with rain rate, and the shape parameter µ exhibited negative values in different rain rate classes. The distribution pattern features were N (D) = 721D-1.79e-1.20D. Distributions of the frequency for mass-weighted mean diameter (Dm) and the logarithm of the generalized intercept parameter (log10 Nw) both showed a unique bimodal type, and an exceptionally high Nw (log10 Nw > 4.5) subset with small Dm was determined. The stratiform and convective rains of RSD were also investigated. Dm - R and Nw - R showed similar variations in two types of precipitation. The lower µ values resulted in higher primary and constant coefficients in the quadratic polynomial fitting for the µ relationship (Λ = 0.0347µ2 + 1.180µ + 2.495). The Z - R relationship (Z for radar reflectivity factor) in stratiform precipitation characteristics was Z = 203R1.59. Further investigations showed that high Nw values usually occurred in persistent precipitation. The RSD can be characterized as high concentrations of the first two diameter classes with a narrow spectrum width (< 1 mm), which were captured during in-cloud rain with a low but continuous rain rate (< 5 mm h-1). The mountainous topography plays an important role in reshaping the characteristics of RSD and physical processes of precipitation. [ABSTRACT FROM AUTHOR]

Background: Pulmonary inflammatory myofibroblastic tumor (PIMT) is a rare disease in China and its incidence is much lower than that of tuberculosis. PIMT accounts for only 0.04-1.2% of all lung tumors. PIMT can occurs in any age and nearly every part of the body. The clinical symptoms and radiological features of PIMT are nonspecific. Diagnosis is only made on the basis of histopathologic or immunohistochemical evaluation of the postoperation resected tissue. The therapeutic approach to PIMT should rely mainly on complete surgical resection.Case Presentation: We report a case of PIMT with hemoptysis. The girl was misdiagnosed with tuberculosis and treated with anti-tuberculous drugs for a long period of time. A right upper and middle lobectomy was performed and further assessment of the tissue demonstrated a pathologic diagnosis of PIMT.Conclusions: Despite a high incidence of tuberculosis, we must consider the possibility of PIMTs in such cases to prevent misdiagnosis and mistreatment. [ABSTRACT FROM AUTHOR]

In recent years, the development of myoelectric control for robotic lower-limb prostheses makes it possible for amputee users to volitionally control prosthetic joints. However, the human-centered control loop is not closed due to the lack of sufficient feedback of prosthetic joint movement, and it may result in poor control performance. In this research, we propose a vibrotactile stimulation system to provide the feedback of ankle joint position, and validate the necessity of combining it with volitional myoelectric control to achieve improved control performance. The stimulation system is wearable and consists of six vibrators. Three of the vibrators are placed on the anterior side of the thigh and the other three on the posterior side of the thigh. To explore the potential of applying the proposed vibrotactile feedback system for prosthetic ankle control, eight able-bodied subjects and two transtibial amputee subjects (TT1 and TT2) were recruited in this research, and several experiments were designed to investigate subjects’ sensitivities to discrete and continuous vibration stimulations applied on the thigh. Then, we proposed a stimulation controller to produce different stimulation patterns according to current ankle angle. Amputee subjects were asked to control a virtual ankle displayed on the computer screen to reach different target ankle angles with a myoelectric controller, and control performances under different feedback conditions were compared. Experimental results indicated that subjects were more sensitive to stimulation position changes (identification accuracies were 96.39 ± 0.86, 91.11, and 93.89% for able-bodied subjects, TT1, and TT2, respectively) than stimulation amplitude changes (identification accuracies were 89.89 ± 2.40, 87.04, and 85.19% for able-bodied subjects, TT1, and TT2, respectively). Response times of able-bodied subjects, TT1, and TT2 to stimulation pattern changes were 0.47 ± 0.02 s, 0.53 s, and 0.48 s, respectively. Furthermore, for both TT1 and TT2, the absolute error of virtual ankle control reduced by about 50% with the addition of vibrotactile feedback. These results suggest that it is promising to apply the vibrotactile feedback system for the control of robotic transtibial prostheses. [ABSTRACT FROM AUTHOR]

Locomotion intent prediction is essential for the control of powered lower-limb prostheses to realize smooth locomotion transitions. In this research, we develop a multi-sensor fusion based locomotion intent prediction system, which can recognize current locomotion mode and detect locomotion transitions in advance. Seven able-bodied subjects were recruited for this research. Signals from two foot pressure insoles and three inertial measurement units (one on the thigh, one on the shank and the other on the foot) are measured. A two-level recognition strategy is used for the recognition with linear discriminate classifier. Six kinds of locomotion modes and ten kinds of locomotion transitions are tested in this study. Recognition accuracy during steady locomotion periods (i.e., no locomotion transitions) is 99.71% ± 0.05% for seven able-bodied subjects. During locomotion transition periods, all the transitions are correctly detected and most of them can be detected before transiting to new locomotion modes. No significant deterioration in recognition performance is observed in the following five hours after the system is trained, and small number of experiment trials are required to train reliable classifiers. [ABSTRACT FROM AUTHOR]

Locomotion mode recognition is one of the key aspects of control of intelligent prostheses. This paper presents a wireless wearable multi-sensor system for locomotion mode recognition. The sensor suit of the system includes three inertial measurement units (IMUs) and eight force sensors. The system was built to measure both kinematic (tilt angles) and dynamic (ground contact forces) signals of human gaits. To evaluate the recognition performance of the system, seven motion modes and sit-to-stand transition were monitored. With a linear discriminant analysis (LDA) classifier, the proposed system can accurately classify the current states. The overall motion mode recognition accuracy was 99.9% during the stance phase and 98.5% during the swing phase. For sit-to-stand transition recognition, the average accuracy was 99.9%. These promising results show the potential of the designed system for the control of intelligent prostheses. [ABSTRACT FROM AUTHOR]

Background It is becoming increasingly necessary for community health centers to make rehabilitation services available to patients with osteoarthritis of the knee. However, for a number of reasons, including a lack of expertise, the small size of community health centers and the availability of only simple medical equipment, conventional rehabilitation therapy has not been widely used in China. Consequently, most patients with knee osteoarthritis seek treatment in high-grade hospitals. However, many patients cannot manage the techniques that they were taught in the hospital. Methods such as acupuncture, tuina, Chinese medical herb fumigation-washing and t'ai chi are easy to do and have been reported to have curative effects in those with knee osteoarthritis. To date, there have been no randomized controlled trials validating comprehensive traditional Chinese medicine for the rehabilitation of knee osteoarthritis in a community health center. Furthermore, there is no standard rehabilitation protocol using traditional Chinese medicine for knee osteoarthritis. The aim of the current study is to develop a comprehensive rehabilitation protocol using traditional Chinese medicine for the management of knee osteoarthritis in a community health center. Method/design This will be a randomized controlled clinical trial with blinded assessment. There will be a 4- week intervention utilizing rehabilitation protocols from traditional Chinese medicine and conventional therapy. Follow-up will be conducted for a period of 12 weeks. A total of 722 participants with knee osteoarthritis will be recruited. Participants will be randomly divided into two groups: experimental and control. Primary outcomes will include range of motion, girth measurement, the visual analogue scale, and results from the manual muscle, six-minute walking and stair-climbing tests. Secondary outcomes will include average daily consumption of pain medication, ability to perform daily tasks and health-related quality-of-life assessments. Other outcomes will include rate of adverse events and economic effects. Relative cost-effectiveness will be determined from health service usage and outcome data. Discussion The primary aim of this trial is to develop a standard protocol for traditional Chinese medicine, which can be adopted by community health centers in China and worldwide, for the rehabilitation of patients with knee osteoarthritis. [ABSTRACT FROM AUTHOR]

In this paper, we present an approach to sense human body capacitance and apply it to recognize lower limb locomotion modes. The proposed wearable sensing system includes sensing bands, a signal processing circuit and a gait event detection module. Experiments on long-term working stability, adaptability to disturbance and locomotion mode recognition are carried out to validate the effectiveness of the proposed approach. Twelve able-bodied subjects are recruited, and eleven normal gait modes are investigated. With an event-dependent linear discriminant analysis classifier and feature selection procedure, four time-domain features are used for pattern recognition and satisfactory recognition accuracies (97.3% ± 0.5%, 97.0% ± 0.4%, 95.6% ± 0.9% and 97.0% ± 0.4% for four phases of one gait cycle respectively) are obtained. The accuracies are comparable with that from electromyography-based systems and inertial-based systems. The results validate the effectiveness of the proposed lower limb capacitive sensing approach in recognizing human normal gaits. [ABSTRACT FROM AUTHOR]

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