22,910 research outputs found

    Recent Advances in Novel Materials and Techniques for Developing Transparent Wound Dressings

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    Optically transparent wound dressings offer a range of potential applications in the biomedical field, as they allow for the monitoring of wound healing progress without having to replace the dressing. These dressings must be impermeable to water and bacteria, yet permeable to moisture vapor and atmospheric gases in order to maintain a moist environment at the wound site. This review article provides a comprehensive overview of the types of wound dressings, novel wound dressing materials, advanced fabrication techniques for transparent wound dressing materials, and the key features and applications of transparent dressings for the healing process, as well as how it can improve healing outcomes. This review mainly focuses on representing specifications of transparent polymeric wound dressing materials, such as transparent electrospun nanofibers, transparent crosslinked hydrogels, and transparent composite films/membranes. Due to the advance properties of electrospun nanofiber such as large surface area, enable efficient incorporation of antibacterial molecules, a structure similar to the extracellular matrix, and high mechanical stability, is often used in wound dressing applications. We also highlight the hydrogels or films for wound healing applications, it's promote the healing process, provide a moisture environment, and offer pain relief with their cool, high-water content, excellent biocompatibility, and bio-biodegradability.Comment: N

    New methodological aspects in rehabilitation after proximal humerus fracture

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    Proximal humerus fracture ranks third in the elderly after femoral neck fractures and distal radius fractures, and seventh in adults, and the risk of occurrence is related to advancing age. In this study we aimed to analyze the efficacy of a 24-weeks physical therapy programme based on a particular methodology consisting of the reprogramming of the specific proprioceptive neuromuscular facil-itation techniques added to the classical physical therapy and by introducing modern interactive therapies and technologies: Capacitive Resistive Electric Transference, Instrument Assisted Soft Tissue Mobilization, kinesiological tapes and PRAMA system, compared with classical physical therapy. Our study included 26 patients, aged between 18 and 55 years, with proximal humerus fracture, who complete the 24-weeks rehabilitation programme. We assessed pain, shoulder range of motion, muscle strength and the ability to perform activities of daily living. The statistical analysis was performed using IBM SPSS and Excel 2021. The results showed statistically significant im-provement in all shoulder motion, increased muscle strength, decreased pain, and a better ability to perform daily activities. The physical therapy programme based on the proposed particular methodology has proven to be more effective than classical physical therapy, both regarding the improvement of the movement parameters compared to the physiological values, as well as the symmetry of both shoulders

    Performance enhancement of the soft robotic segment for a trunk-like arm

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    Introduction: Trunk-like continuum robots have wide applications in manipulation and locomotion. In particular, trunk-like soft arms exhibit high dexterity and adaptability very similar to the creatures of the natural world. However, owing to the continuum and soft bodies, their performance in payload and spatial movements is limited.Methods: In this paper, we investigate the influence of key design parameters on robotic performance. It is verified that a larger workspace, lateral stiffness, payload, and bending moment could be achieved with adjustments to soft materials’ hardness, the height of module segments, and arrayed radius of actuators.Results: Especially, a 55% increase in arrayed radius would enhance the lateral stiffness by 25% and a bending moment by 55%. An 80% increase in segment height would enlarge 112% of the elongation range and 70 % of the bending range. Around 200% and 150% increments in the segment’s lateral stiffness and payload forces, respectively, could be obtained by tuning the hardness of soft materials. These relations enable the design customization of trunk-like soft arms, in which this tapering structure ensures stability via the stocky base for an impact reduction of 50% compared to that of the tip and ensures dexterity of the long tip for a relatively larger bending range of over 400% compared to that of the base.Discussion: The complete methodology of the design concept, analytical models, simulation, and experiments is developed to offer comprehensive guidelines for trunk-like soft robotic design and enable high performance in robotic manipulation

    Methods for solving mathematical Laplace equation for calculating transient process of short-term braking mode of traction electric motors (KTR TED) of diesel locomotive of TE10 type

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    In this article, ways to improve the device's efficiency for damping the field of a traction generator were considered. In the developed solution, containing a traction generator with an independent excitation winding, in parallel with which traction motors are switched on by power contacts that are switched off with a time delay, a power contact, switched from the first position from the controller, an excitation contactor, in the circuit of which the protection of the diesel generator set is connected in series, adjustable traction generator field damping resistance, connected in series in the conductive direction between the minus of the exciter and the traction generator field damping resistance, a diode, as well as excitation weakening contactors, switched on by the contacts of differential relays of the first and second stages for the current and voltage of the traction generator, connecting resistance power contacts parallel to the traction windings motors, and normally -open auxiliary contacts are connected parallel to the parts of the adjustable resistance to damping the field of the traction generator

    Recent developments in 2D materials for energy harvesting applications

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    The ever-increasing demand for energy as a result of the growing interest in applications, such as the Internet of Things and wearable systems, etc, calls for the development of self-sustained energy harvesting solutions. In this regard, 2D materials have sparked enormous interest recently, due to their outstanding properties, such as ultra-thin geometry, high electromechanical coupling, large surface area to volume ratio, tunable band gap, transparency and flexibility. This has given rise to noteworthy advancements in energy harvesters such as triboelectric nanogenerators (TENGs), piezoelectric nanogenerators (PENGs) and photovoltaics based on 2D materials. This review introduces the properties of different 2D materials including graphene, transition metal dichalcogenides, MXenes, black phosphorus, hexagonal boron nitride, metal-organic frameworks and covalent-organic frameworks. A detailed discussion of recent developments in 2D materials-based PENG, TENG and photovoltaic devices is included. The review also considers the performance enhancement mechanism and importance of 2D materials in energy harvesting. Finally, the challenges and future perspectives are laid out to present future research directions for the further development and extension of 2D materials-based energy harvesters

    Distinct genomic routes underlie transitions to specialised symbiotic lifestyles in deep-sea annelid worms.

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    Bacterial symbioses allow annelids to colonise extreme ecological niches, such as hydrothermal vents and whale falls. Yet, the genetic principles sustaining these symbioses remain unclear. Here, we show that different genomic adaptations underpin the symbioses of phylogenetically related annelids with distinct nutritional strategies. Genome compaction and extensive gene losses distinguish the heterotrophic symbiosis of the bone-eating worm Osedax frankpressi from the chemoautotrophic symbiosis of deep-sea Vestimentifera. Osedax's endosymbionts complement many of the host's metabolic deficiencies, including the loss of pathways to recycle nitrogen and synthesise some amino acids. Osedax's endosymbionts possess the glyoxylate cycle, which could allow more efficient catabolism of bone-derived nutrients and the production of carbohydrates from fatty acids. Unlike in most Vestimentifera, innate immunity genes are reduced in O. frankpressi, which, however, has an expansion of matrix metalloproteases to digest collagen. Our study supports that distinct nutritional interactions influence host genome evolution differently in highly specialised symbioses

    Beam scanning by liquid-crystal biasing in a modified SIW structure

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    A fixed-frequency beam-scanning 1D antenna based on Liquid Crystals (LCs) is designed for application in 2D scanning with lateral alignment. The 2D array environment imposes full decoupling of adjacent 1D antennas, which often conflicts with the LC requirement of DC biasing: the proposed design accommodates both. The LC medium is placed inside a Substrate Integrated Waveguide (SIW) modified to work as a Groove Gap Waveguide, with radiating slots etched on the upper broad wall, that radiates as a Leaky-Wave Antenna (LWA). This allows effective application of the DC bias voltage needed for tuning the LCs. At the same time, the RF field remains laterally confined, enabling the possibility to lay several antennas in parallel and achieve 2D beam scanning. The design is validated by simulation employing the actual properties of a commercial LC medium

    Crossing the Rift valley: using complete mitogenomes to infer the diversification and biogeographic history of ethiopian highlands Ptychadena (anura: Ptychadenidae)

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    The Ethiopian Highlands are considered a biodiversity hotspot, harboring a high number of endemic species. Some of the endemic species probably diversified in situ; this is, for example, the case of a monophyletic clade containing 12 known species of grass frogs of the genus Ptychadena. The different species occur at elevations ranging from 1,500 to above 3,400 m and constitute excellent models to study the process of diversification in the highlands as well as adaptations to high elevations. In this study, we sampled 294 specimens across the distribution of this clade and used complete mitogenomes and genome-wide SNP data to better understand how landscape features influenced the population structure and dispersal of these grass frogs across time and space. Using phylogenetic inference, population structure analyses, and biogeographic reconstructions, we found that the species complex probably first diversified on the south-east side of the Great Rift Valley. Later on, species dispersed to the north-west side, where more recent diversification occurred. We further demonstrate that Ptychadena species have dispersed across the Great Rift Valley at different times. Our analyses allowed for a more complete understanding of the contribution of geological events, biogeographic barriers and climatic changes as drivers of species diversification and adaptation in this important biogeographic region

    A hydrogel-based first-aid tissue adhesive with effective hemostasis and anti-bacteria for trauma emergency management

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    Abstract Background Clinical tissue adhesives remain some critical drawbacks for managing emergency injuries, such as inadequate adhesive strength and insufficient anti-infection ability. Herein, a novel, self-healing, and antibacterial carboxymethyl chitosan/polyaldehyde dextran (CMCS/PD) hydrogel is designed as the first-aid tissue adhesive for effective trauma emergency management. Methods We examined the gel-forming time, porosity, self-healing, antibacterial properties, cytotoxicity, adhesive strength, and hemocompatibility. Liver hemorrhage, tail severance, and skin wound infection models of rats are constructed in vivo, respectively. Results Results demonstrate that the CMCS/PD hydrogel has the rapid gel-forming (~ 5 s), good self-healing, and effective antibacterial abilities, and could adhere to tissue firmly (adhesive strength of ~ 10 kPa and burst pressure of 327.5 mmHg) with excellent hemocompatibility and cytocompatibility. This suggests the great prospect of CMCS/PD hydrogel in acting as a first-aid tissue adhesive for trauma emergency management. The CMCS/PD hydrogel is observed to not only achieve rapid hemostasis for curing liver hemorrhage and tail severance in comparison to commercial hemostatic gel (Surgiflo ®) but also exhibit superior anti-infection for treating acute skin trauma compared with clinical disinfectant gel (Prontosan ®). Conclusions Overall, the CMCS/PD hydrogel offers a promising candidate for first-aid tissue adhesives to manage the trauma emergency. Because of the rapid gel-forming time, it could also be applied as a liquid first-aid bandage for mini-invasive surgical treatment. Graphical Abstrac

    THE KNOWLEDGE AND ATTITUDES OF THE COMMUNITY IN SIBANGKAJA VILLAGE, BADUNG, REGARDING THE RABIES INCIDENT

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    Background: The challenges in overcoming the rabies epidemic include the public's lack of knowledge and attitudes regarding the control and first aid in dog bites. Sibangkaja is one of the villages in Badung Regency, which is an endemic area for rabies. Purpose: This study aimed to describe the knowledge, attitudes, and factors influencing the behavior of the residents of Sibangkaja Village, Badung, regarding rabies. Methods: This descriptive observational study was carried out using a cross-sectional design. The samples were 250 residents of Sibangkaja Village, taken by convenience sampling. Data were collected from February to March 2020 through interviews using the digital questionnaire. The variables were knowledge and community attitudes toward rabies vaccination in the village. Results: The results showed that the respondents' knowledge was good, but 34% did not know the symptoms of rabies. It was discovered that attitudes toward rabies prevention and management are significantly more in favor of vaccination than eliminating dogs. Furthermore, there is an association between knowledge and dog ownership on people's attitudes (p-value=0.01). Conclusion: Information and education about the symptoms of rabies is needed for residents to exercise caution and pay more attention to themselves and the surrounding dogs. Results: The results showed that the respondents' knowledge of rabies was good, but 34% of the people of Sibangkaja Village did not know the symptoms of rabies. Attitudes toward rabies prevention and management are largely in favor of vaccination than elimination of dogs. Conclusion: Information and education is needed regarding the symptoms of rabies so that residents are able to be careful and pay more attention to themselves and the dogs around them
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