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Impact of optimized and conventional facility designs on outpatient abdominal MRI workflow efficiency
Effect of SiO2 aerogel and perlite on properties of foamed concrete
SGA-Driven feature selection and random forest classification for enhanced breast cancer diagnosis: A comparative study
Multimodal contrastive learning for enhanced explainability in pediatric brain tumor molecular diagnosis
Growth variability of farm grown teak in response to climatic and soil factors across three agroclimatic zones of Tamil Nadu, India
Ultra-lightweight robotic hip exoskeleton with anti-phase torque symmetry for enhanced walking efficiency
Abstract This paper presents a novel robotic exoskeleton that is exceptionally lightweight and compact, while providing effective gait assistance. To maximize the system’s assistance-to-weight/size ratio, the design focuses on two key aspects of human gait mechanics: (1) the contribution of the hip joints to power generation, and (2) the symmetrical nature of hip flexion and extension torques during walking. Based on these principles, we developed a compact hip exoskeleton with a single actuator. This actuator simultaneously drives the hip joint in the sagittal plane, facilitating both flexion and extension during gait. An adaptive delayed output feedback controller was implemented, ensuring consistent performance across diverse walking conditions using a single rotational sensor and actuator. To evaluate the exoskeleton’s effectiveness, a 4-week outdoor walking exercise program was conducted with nine elderly participants. Their gait, balance, and muscle strength were measured before and after the program to assess improvements. Results showed significant improvements in walking speed (14.8% in the 10-m walk and 10.6% in the 6-min walk), as well as enhanced performance in the timed up-and-go test (24.5%) and the short physical performance battery test (18.7%). Ankle dorsiflexion and plantar flexion muscle strength increased by 75.45% and 45.8%, respectively. Additionally, metabolic measurements from three young adults indicated a 13.6 ± 3.2% reduction in the net metabolic cost of walking with the exoskeleton compared to walking without it. These results demonstrate that the single actuator-based hip exoskeleton offers effective gait assistance while maintaining a lightweight and compact design, highlighting its potential for widespread use in various applications.
Effect of nanosecond laser assisted surface modification on physical and mechanical properties of denture base materials
Abstract Lasers are being used for modifying the surfaces of biomaterials to make them resistant to microbial adhesion. However, the effect of such surface modification on physical and mechanical properties has not been widely reported. The aim of the study was to investigate the effect of surface modification using laser patterning on the physical and mechanical properties of denture base materials. Nd: YAG nanosecond laser was used to create different patterns on two commercial denture base materials. Surface characteristics of the patterned specimens such as surface roughness, contact angle and resistance to microbial adhesion were measured. Laser patterned specimens with lower microbial adhesion were subjected to evaluation of mechanical (flexural strength and surface hardness) and physical (water sorption and solubility) properties using standard methods. Laser patterning increased the surface roughness, contact angle and the resistance to microbial adhesion. Laser patterning did not have any detrimental effects on mechanical and physical properties. However, a significant increase in surface hardness was observed in all patterned specimens. By fine-tuning the laser patterning parameters, it is possible to create surfaces with enhanced resistance to microbial adhesion without compromising the physical and mechanical properties of the material, which can ultimately lead to better oral health outcomes for denture users.
Diabetes mellitus among HIV patients on ART at Woldia comprehensive specialized hospital, Northeast Ethiopia
Abstract Diabetes mellitus (DM) is an emerging comorbidity among people living with HIV receiving antiretroviral therapy (ART), potentially impacting treatment outcomes, including virologic failure. Identifying key determinants of DM in this population is crucial for improving patient care. A hospital-based cross-sectional study was conducted from January 01 to May 30, 2024 at Woldia Comprehensive Specialized Hospital, Ethiopia. A total of 253 HIV patients on ART for at least six months were randomly selected. Data were collected via structured questionnaires, clinical measurements, and medical record reviews. DM was diagnosed on the basis of a fasting blood glucose level ≥ 126 mg/dl or random plasma glucose level ≥ 200 mg/dl. Logistic regression models were employed to identify factors associated with DM, reporting adjusted odds ratios (AORs) with 95% confidence intervals (CIs). Statistical significance was set at p < 0.05. The prevalence of DM among the study participants was 9.9%. Compared with female patients, male patients had a significantly greater risk of developing DM (AOR = 4.29, 95% CI = 1.079–17.04). A family history of DM was associated with a nearly 11-fold increased risk (AOR = 10.65, 95% CI = 2.82–40.20). Overweight individuals (BMI > 25 kg/m²) had a nearly sixfold-fold greater risk of DM (AOR = 5.95, 95% CI = 1.56–22.65). Additionally, ART interruption and restarting of ART were significantly associated with increased DM risk (AOR = 6.11, 95% CI = 1.88–19.84). Approximately one in ten HIV patients on ART had DM. The significant factors included male sex, family history of DM, overweight status, and ART interruption. These findings highlight the need for routine metabolic screening, targeted interventions and continuous monitoring to mitigate DM risk and optimize HIV care.
SSDDPM: A single SAR image generation method based on denoising diffusion probabilistic model
Characterization and therapeutic potential of newly isolated bacteriophages targeting the most common Salmonella serovars in Europe
Unlocking terpenoid treasures of rhizome and leaf volatiles of Curcuma caesia Roxb through 1D and 2D GC × GC TOFMS analysis
MRI-guided biopsy reduces biochemical recurrence in prostate cancer patients undergoing radiation therapy: a single-center study from Thailand
Investigation of the effects of concentration and voltage on the physicochemical properties of Nylon 6 nanofiber membrane
Abstract The nanofibers of Nylon 6 at different concentrations 14 wt%, 16% wt%, and 18 wt% were fabricated using electrospinning method. The effect of concentration and voltage on the morphology of the nanofibers were assessed through the utilisation of FTIR, XRD, Raman spectroscopy, atomic force microscopy AFM, scanning electron microscopy SEM, and EDS techniques. A study on the Nylon 6 molecule using DFT (Density Functional Theory) was conducted. Nylon 6 optimized molecular structure, featuring an amine group and nitrogen atom for electrophilic reactions, exhibits high kinetic stability with a measured band gap energy of 6.60 eV and electronic chemical potential of -3.83. The diameter of the fibres increased from 76.91 to 81.98 nm when the concentration and voltage were further increased, with the respective weight percentages of 14 wt% and 18 wt%. This work reveals the influence of concentration and voltage on the physical and chemical characteristics of nylon-6 NFM and its quantum electronic properties.
The perceptual and biomechanical effects of scaling back exosuit assistance to changing task demands
Determination and application of soil heavy metal geochemical baseline in the southern region of Wushan County in the Yangtze River Basin, China
Mettl3 deficiency leads to impaired insulin secretion via regulating Ire1a of mature β-cells in mice
Noninvasive estimation of internal spinal alignment in patients with adolescent idiopathic scoliosis using PCdare and back shape asymmetry
Abstract Optical 3D surface scanning is used increasingly to assess spinal deformity in patients with adolescent idiopathic scoliosis (AIS), largely because it avoids additional radiation burden. However, such approaches generally underestimate the extent of the abnormality. Improving the accuracy of such estimates requires a deeper understanding of AIS and its effect on back shape. We present a unique platform with publicly available code that contains noninvasive and nonionizing approaches to estimating the Cobb angle of the primary curve, called primary Cobb angle (pCA) and internal spinal alignment (ISL) in patients with AIS. Our approaches use asymmetries of the back shape during upright standing, the Adam’s forward bending test, bending forward, and lateral bending. The results have revealed strong (0.75 [0.53, 0.87]) to excellent (0.91 [0.81, 0.96]) correlations [95% confidence interval] and a median pairwise absolute error (IQR) of 3.4° (6.8°) between the estimated pCAs and clinical gold-standard assessments in 30 patients. The correlations (IQR) between estimated shape of ISLs and their references were very strong (0.87 (0.24)) to excellent (0.94 (0.03)), and the median root mean square error (IQR) between estimated and reference ISL was 6.9 mm (3.3 mm). These results indicate confidence both in the use of 3D scanning using a “back-shape-to-spine” approach and in the establishment of optical 3D surface scanning approaches for scoliosis screening and monitoring in clinical practice.
Multi-user frequency selective beam steering by reconfigurable intelligent surfaces in the Ka-band
Abstract Reconfigurable intelligent surfaces (RIS) have been proposed to extend the coverage of wireless communication signals at mm-wave frequencies. Here, we designed and fabricated a reconfigurable intelligent surface (RIS) for multi-user frequency selective beam steering (MU-FSBS) that achieves higher channel capacity than traditional time division multiple access (TDMA) techniques in multi-user communication scenarios. MU-FSBS is enabled by a varactor diode-tuned RIS that allows to steer several beams in the Ka-band independently at the same time. For such targeted multi-frequency beam steering, we implemented a customized neural network-based machine learning architecture specifically designed to optimize the bias voltage patterns of the RIS. As an experimental demonstration, we first accomplished independent beam steering of normally incident beams at 27 GHz and 31 GHz to deflection angles between 10 $$^\circ$$ and 45 $$^\circ$$ in a defined plane. Secondly, we compared the achievable channel capacities of the proposed MU-FSBS approach with those of TDMA, finding an average increase of approximately 50% in channel capacity at a fixed SNR of 20 dB. At an SNR of 60 dB, MU-FSBS even demonstrated a remarkable 84% increase in channel capacity compared to TDMA.