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The hilly red soil region of southern China suffers from severe soil erosion that has led to soil degradation and loss of soil nutrients. Estimating the content and spatial variability of soil organic carbon (SOC) and soil total nitrogen (STN) and assessing the influence of topography and land-use type on SOC and STN after years of soil erosion control are important for vegetation restoration and ecological reconstruction. A total of 375 topsoil samples were collected from Changting County, and their SOC and STN distributions were studied by using descriptive statistics and geostatistical methods. Elevation, slope, aspect and land-use type were selected to investigate the impacts of natural and human factors on the spatial heterogeneity of SOC and STN. The mean SOC and STN concentrations were 15.85 and 0.98 g kg -1 with moderate spatial variations, respectively. SOC and STN exhibited relatively uniform distributions that decreased gradually from the outside parts to the center of the study area. The SOC and STN contents in the study area were still at moderate and low levels after years of erosion control, which suggests that soil nutrient improvement is a slow process. The lowest SOC and STN values were at lower elevations in the center of Changting County. The results indicated that the SOC and STN contents increased most significantly with elevation and slope due to the influence of topography on the regional natural environment and soil erosion in the eroded hilly region. No significant variations were observed among different slope directions and land-use types.

N6-methyladenosine (m 6 A) is dynamically regulated by methyltransferases (termed “writers”) and demethylases (referred to as “erasers”), facilitating a reversible modulation. Changes in m 6 A levels significantly influence cellular functions, such as RNA export from the nucleus, mRNA metabolism, protein synthesis, and RNA splicing. They are intricately associated with a spectrum of pathologies. Moreover, dysregulation of m 6 A modulation has emerged as a promising therapeutic target across many diseases. m 6 A plays a pivotal role in controlling vital downstream molecules and critical biological pathways, contributing to the pathogenesis and evolution of numerous conditions. This review provides an overview of m 6 A demethylases, explicitly detailing the structural and functional characteristics of FTO and ALKBH5. Additionally, we explore their distinct involvement in various diseases, examine factors regulating their expression, and discuss the progress in inhibitor development.

In the Qinghai-Tibet Plateau, fractures and fault zones have developed in this area, where earthquakes and extreme rainfall frequently induce debris flow disasters, which seriously threaten the safety of the people and properties. In this study, Zhujiagou, Minxian County, Gansu Province in China, has a typical debris flow channel in a small watershed on the northeastern edge of the Qinghai-Tibet Plateau, which has been used as the case study for risk assessment. A debris flow-risk assessment method has been developed in this study. The fusion algorithm of entropy weight and coefficient of variation has been used to evaluate the susceptibility of debris flow in each tributary channel in the watershed. Further, numerical simulation of the debris flow events at the main channel and at the high-prone debris flow tributary channel has been carried out. The \"7.18\" Zhujiagou debris flow event has been used to verify that the accuracy of the numerical simulation is higher than 74.12%. This method has been applied to design the Zhujiagou debris flow-risk zoning under extreme rainfall conditions, aimed at forming a set of debris flow-risk evaluation system suitable for this type of small watershed. The results show that the peak single-width clear water flow at the mouth of the channel, the length of the channel, and the shallow surface rock formation are the main factors influencing the susceptibility of debris flow. The main tributaries of the watershed are Hagu channel, Zhuling channel, Songshu channel, and Langjia channel which are all high-prone debris flow channels. The Zhujiagou debris flow accumulation fan under the designed 1% rainfall frequency will block the Taohe, which will threaten the safety of the residents and properties near the channel, at the mouth of the channel and in the urban area on the opposite bank of the Taohe. Compared with Hagugou, Zhulinggou, and Songshugou, the low-risk area is Langjiagou. The research results of this study can be used for evaluation methods and as a basis for preventing debris flow disasters on the northeastern edge of the Qinghai-Tibet Plateau.

Pinus massoniana is the pioneer tree species in the red soil regions of southern China, however, the serious understory soil erosion and nutrient deficiency in that region are the main factors restricting the growth of P. massoniana. This field study examined the effects of compound fertilizer and super absorbent polymer (SAP) on the physiology, growth characteristics, biomass, soil nutrient, plant nutrient content, and nutrient uptake efficiency of 1-year-old P. massoniana seedlings for 2 years at Changting, Fujian in South China. One control (no fertilizer, CK) and fertilization treatments were established, namely, single compound fertilizer application (0.94, 1.89, and 3.56 g⋅plant –1 ) and mixture compound fertilizer and SAP application (0.94 + 1.01, 1.89 + 1.01, and 3.56 + 1.01 g⋅plant –1 ). Fertilization significantly improved the physiological performance, root collar diameter growth, height growth, biomass, and nutrient uptake of the seedlings. Compared with other fertilization treatments, the mixture compound fertilizer and SAP application significantly improved the seedling photosynthesis, which meant that the SAP had a significant effect on promoting photosynthesis. Under the mixture compound fertilizer and SAP application, the whole biomass of the seedlings was higher than that of all other treatments. Fertilization significantly increased the nitrogen (N), phosphorus (P), and potassium (K) content in the soils, leaves, stems, and roots of the seedlings, respectively. The P content was the main factor affecting growth characteristics and contributed to 58.03% of the total variation in seedling growth characteristics ( P < 0.01). The N:P ratio of CK in the soils, leaves, and stems were higher than that of all the fertilization treatments, indicating that the severely eroded and degraded region had little P and required much of P. The principal component analysis indicated that the F2S (1.89 + 1.01 g) was the optimum fertilization amount and method in this experiment. These results provide a theoretical basis for the fertilization management of P. massoniana forests with severely eroded and degraded red soil regions.

Soil erosion by water is a serious environmental problem in southern China, particularly in the Zhuxi watershed in Changting County of the Fujian Province, which is characterized by highly erosive rainfall, severely undulating terrain, porous soil, scarce vegetation, and excessive human activity. The evaluation of soil erosion vulnerability is important for soil resources and sustainable development. Using the Zhuxi watershed as an example of soil erosion problems, this study uses the analytic hierarchy process to evaluate soil erosion vulnerability in a coupled human and natural system to determine the proportions of factors in an index system based on the experience of experts. Using GIS, we confirmed that the factors in the utilized index system were exposure, sensitivity, and adaptive capacity to soil erosion. All of these factors were combined to determine the soil erosion vulnerability. The results indicated severe soil erosion vulnerability over large areas. The areas vulnerable to soil erosion accounted for 57.98 % of the watershed; and the areas damaged to a high or very high extent account for over 12.08 % of the watershed. The results also show that the soil erosion vulnerability varies in different locations. For example, soil erosion vulnerability is lower in the eastern part of the study area and higher in the western part. Therefore, an effective approach to reduce soil erosion vulnerability would be to implement measures for regional soil and water conservation and sustainable development.

Loss of soil nutrients in runoff accelerates eutrophication of surface waters. This study found out the critical of rainfall intensity and slope angles of total nitrogen and phosphorus in surface runoff for degraded Ferralsols in southern China. We established plots (1.5 m × 0.5 m × 0.3 m; length × width × height) to investigate the effects of rainfall intensity (1.0, 1.5, 2.0 mm min−1) and slope gradients (10°, 15°, 20°) on runoff rate, total nitrogen and total phosphorus loss rates and dynamic factors. Our results indicated that a slope gradient of 15° is suitable for controlling TN and TP losses in degraded Ferralsols, 1.5 mm min−1 is the critical rainfall intensity of nitrogen and phosphorus loss in runoff in our study, runoff rate determines runoff-associated TN and TP losses, and runoff shear force is the dynamic factor for nitrogen and phosphorus losses. Our study might also be helpful for predicting water erosion and non-point source pollution in large scales and natural slope scales and building a model of soil erosion watershed scales.

Soil erosion is a type of land degradation caused by the interactive interaction of numerous factors, such as natural and socioeconomic conditions of a particular watershed. In this study, a comprehensive integrated methodology was used to evaluate the water erosion hazard in the Zhuxi watershed in Southern China, which is greatly affected by eroded soil. Ten indicators were selected, and a thematic layer map was generated for each indicator using Geographic Information System (GIS). The weight of each evaluation indicator was determined by combining analytic hierarchy process (AHP) with entropy method. Results show that the east and west sections of the Zhuxi watershed have very low and low grades of soil erosion hazards, respectively, and the middle part has the highest hazard. More than 60% of the area has high erosion hazard (moderate to very high). The intensity of soil erosion is lower than its hazard level, especially in high-grade hazard. The obtained results for erosion hazard level can be used to develop conservation strategies for the Zhuxi watershed. This study evaluates soil erosion hazard and offers reference for soil erosion control.

We present the design of a new controlled drug delivery system potential for in vitro injection of diabetics. The system incorporates some integrated circuit units and microelectromechanical system devices, such as micropump, microneedle array and microsensor. Its goal is to achieve safer and more effective drug delivery. Moreover, a valveless micropump excited by the piezoelectric actuator is designed for the drug delivery system, and a simple fabrication process is proposed. A dynamic model is developed for the valveless micropump based upon the mass conservation. To characterize the micropump, a complete electro-solid-fluid coupling model, including the diffuser/nozzle element and the piezoelectric actuator, is built using the ANSYS software. The simulation results show that the performance of micropump is in direct proportion to the stroke volume of the pump membrane and there is an optimal thickness of the piezoelectric membrane under the 500 V/mm electric field. Based on this simulation model, the effects of several important parameters such as excitation voltage, excitation frequency, pump membrane dimension, piezoelectric membrane dimension and mechanical properties on the characteristics of valveless micropump have been investigated.[PUBLICATION ABSTRACT]

We designed a valveless micropump excited by a piezoelectric actuator for medical applications. The complete electric–fluid–solid coupling model is built upon using ANSYS software (Canonsburg, PA) to investigate the behaviors of the micropump. The effects of the geometrical dimensions on the micropump characteristics and its efficiency are analyzed. The simulation results show that there is an optimal thickness of the piezoelectric layer to obtain a large pump flow, and that this optimal thickness is affected by the material and the thickness of the pump membrane. To enhance the performance of the micropump, some important diffuser parameters, such as the diffuser length, the diffuser angle, and the neck width, should be optimized. However, the variations of the diffuser’s geometrical dimensions do not affect the optimal thickness of the piezoelectric layer.

This paper reports the work of selecting suitable manufacturing processes and materials in concurrent design for manufacturing environment. In the paper, a fuzzy knowledge-based decision support method is proposed for multi-criteria decision-making in evaluating and selecting possible manufacturing process/material combinations in terms of the total production cost. Based on the proposed method, a prototype Web-based knowledge-intensive manufacturing consulting service system (WebMCSS) with the client-knowledge server architecture is developed to help designers/users find good processes and materials while still at the conceptual level of design. The system, as one of the important parts of an advanced design for manufacturing tool, is a concept level process and material selection tool that can be used as both a standalone application and a Java applet freely available via the Web. Interlinked with Web pages of tutorials, and reference pages explaining the facets, fabrication processes and material choices, the system performs reasoning and calculations using the process capability and material property data from the remote Web-based database and knowledge base that can be maintained and updated via the Internet. The use of the system is illustrated with an example.