37 research outputs found

    Techniques and graft materials for repairing peripheral nerve defects

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    Peripheral nerve defects refer to damage or destruction occurring in the peripheral nervous system, typically affecting the limbs and face. The current primary approaches to address peripheral nerve defects involve the utilization of autologous nerve transplants or the transplantation of artificial material. Nevertheless, these methods possess certain limitations, such as inadequate availability of donor nerve or unsatisfactory regenerative outcomes post-transplantation. Biomaterials have been extensively studied as an alternative approach to promote the repair of peripheral neve defects. These biomaterials include both natural and synthetic materials. Natural materials consist of collagen, chitosan, and silk, while synthetic materials consist of polyurethane, polylactic acid, and polycaprolactone. Recently, several new neural repair technologies have also been developed, such as nerve regeneration bridging technology, electrical stimulation technology, and stem cell therapy technology. Overall, biomaterials and new neural repair technologies provide new methods and opportunities for repairing peripheral nerve defects. However, these methods still require further research and development to enhance their effectiveness and feasibility

    Mechanisms and recent advances in the diagnosis and treatment of nitrous oxide-induced peripheral neuropathy: a narrative review

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    Under standard conditions, nitrous oxide (N2O) manifests as a colorless, odorless gas with a mildly sweet taste. The compound finds applications in various fields, including its use as an aerosol propellants, an accelerant in motor racing, and an anesthetic in surgical procedures and dentistry. Unfortunately, the recreational misuse of N2O has become prevalent among young individuals due to its euphoric and hallucinogenic effects. Compounding this issue is the fact that nitrous oxide can be easily obtained from over-the-counter household items, facilitating its non-medical use. The global community has witnessed a surge in the recreational utilization of nitrous oxide gas in recent years. Despite the widespread non-medical abuse of N2O, there remains inadequate understanding of the potential adverse effects resulting from exposure to it. This paper provides an overview of management findings, laboratory and electrodiagnostic characteristics, as well as clinical presentations associated with neurological disorders induced by nitrous oxide usage

    Environmental, Ecological, and Economic Benefits of Biofuel Production Using a Constructed Wetland: A Case Study in China

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    Here we show a constructed wetland (CW), a viable alternative wastewater treatment system, be used to produce biofuels from biomass by using nitrogen contained in domestic wastewater. We summarize the potential biomass yield evaluated as cellulosic ethanol bioenergy production, and combine the life cycle analysis with a mass balance approach to estimate the energetic, environmental, and economic performance of a CW biofuel system. The results showed that the annual aboveground biomass yield of a CW in Zhoushan, Zhejiang Province, China, averaged 37,813 kg ha−1 year−1 as the by-product of treating waste N, which is about one order of magnitude larger than traditional biofuel production systems. The biomass yield in the Zhoushan CW system had life cycle environment benefits of 8.8 Mg (1 Mg = 106 g) CO2 equivalent ha−1 year−1 of greenhouse gas emission reduction. The CW in Zhoushan had a net energy gain of 249.9 GJ (1 GJ = 109 J) ha−1 year−1 while the wastewater treatment plant (WTP) consumes 7442.5 GJ ha−1 year−1. Moreover, the CW reduced greenhouse gas emissions to 2714 times less than that of the WTP. The CW also provided various ecosystem services, such as regional climate regulation and habitat conservation. We suggest that the potential use of a CW as biofuel production and carbon sequestration via nitrogen-negative input can be explored more widely in the future

    Carbon storage and its changes in Chinese terrestrial ecosystem in recent decades

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    This paper made a comprehensive assessment on carbon storage in terrestrial ecosystem in China by reviewing published literatures. Much more detailed carbon storages in vegetation, soil and ecosystem were summarized for forest, grassland, shrub, cropland and wetland in recent decades. It was discovered that total terrestrial carbon storage in China was 67.9 ~191.8 Pg C in recent decades, 6.1 ~ 57.57 Pg C was stored in vegetation, and 161.7 ~ 185.7 Pg C was stored in topsoil at a depth of 100 cm. Vegetation carbon storage has increased obviously in recent years; soil carbon storage declined in some areas owing to intensive land use, while it increased in other areas because of fertilizer application and reforestation. Total terrestrial carbon storage over China has increased in recent decades, and it is expected to continue to increase

    Adaptive Neural Control of Hypersonic Vehicles with Actuator Constraints

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    An adaptive neural control method is proposed in this paper for the flexible air-breathing hypersonic vehicle (AHV) with constraints on actuators. This scheme firstly converts the original control problem with input constraints into a new control problem without input constraints based on the control input saturation function. Secondly, on the basis of the implicit function theorem, the radial basis function neural network (RBFNN) is introduced to approximate the uncertain items of the model. And the minimal-learning-parameter (MLP) technique is adopted to design the adaptive law for the norm of network weight vector, which significantly reduces calculations. Meanwhile, the finite-time convergence differentiator (FD) is introduced, through which the model state variables and their derivatives are accurately estimated to ensure the control effect. Finally, it is theoretically proved that the closed-loop control system is stable. And the effectiveness of the designed controller is verified by simulation

    Analysis of the Ecosystem Soil Conservation Function Based on the Major Function-Oriented Zones across the Yangtze River Economic Belt, China

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    The Yangtze River Economic Belt (YREB) is an important ecological security barrier for China. The spatial-temporal pattern of land use changes and changing characteristics of soil conservation function were analyzed based on the Major Function-Oriented Zones (MFOZs) from 2010 to 2015. Soil conservation was calculated by the Revised Universal Soil Loss Equation (RUSLE). Results were as follows: in 2015, the area ratio of built-up land in the optimal development zones (ODZs), key development zones (KDZs), agricultural production zones (APZs) and key ecological function zones (KEFZs) was 25.25%, 6.55%, 3.70% and 0.40%, respectively, which reflected the gradient of territorial development based on their functions. The average annual soil retention was 18.76 billion t/year during the study period, and the per unit soil retention was 91.54 t/hm2/year. The soil conservation function capacity was weakened in the order of KEFZs, APZs, KDZs and ODZs. Soil conservation function of the YREB showed an overall improvement from 2010 to 2015. The implementation of the MOFZs strategy has contributed significantly to improving the ecological security capability of the YREB

    Carbon storage and its changes in Chinese terrestrial ecosystem in recent decades

    No full text
    This paper made a comprehensive assessment on carbon storage in terrestrial ecosystem in China by reviewing published literatures. Much more detailed carbon storages in vegetation, soil and ecosystem were summarized for forest, grassland, shrub, cropland and wetland in recent decades. It was discovered that total terrestrial carbon storage in China was 67.9 ~191.8 Pg C in recent decades, 6.1 ~ 57.57 Pg C was stored in vegetation, and 161.7 ~ 185.7 Pg C was stored in topsoil at a depth of 100 cm. Vegetation carbon storage has increased obviously in recent years; soil carbon storage declined in some areas owing to intensive land use, while it increased in other areas because of fertilizer application and reforestation. Total terrestrial carbon storage over China has increased in recent decades, and it is expected to continue to increase
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