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In cold regions, freeze-thaw cycles play a critical role in many engineering and agricultural applications and cause soil water flow and heat transport studies to be much more complicated due to phase changes involved. A fully coupled numerical module for simulating the simultaneous movement of water, vapor, and heat during freezing-thawing periods was developed and incorporated in the Hydrus-1D software in this study. To avoid numerical instabilities caused by a sudden increase in the apparent heat capacity during a phase change, a new approach based on the available energy concept was adopted to adjust soil temperature when the freezing temperature is reached. The proposed freezing module's performance was then validated using experimental data collected at three field sites with typical seasonal freezing/thawing processes. Results showed that the model could efficiently obtain a convergent solution and that simulated soil moisture and temperature variations captured the observed data well. Driven by soil matric potential and temperature gradients, both liquid water and water vapor flowed towards the freezing front. The isothermal liquid flux was the most significant component of overall flow in most soil depths except in the frozen layer, where it decreased by 1–5 orders of magnitude from values before freezing. Instead, the thermal vapor flux was the dominant moisture transfer mechanism in the frozen layer and contributed about 10% to the ice formation. These results indicate that the model, which considers the coupled movement of water, vapor, and heat, can better describe the physical mechanisms of the hydrological cycle in the vadose zone during the freezing-thawing periods. © 2021 Elsevier B.V.

Freeze-thaw cycles play a critical role in affecting ecosystem services in arid regions. Monitoring studies of soil temperature and moisture during a freeze-thaw process can generate data for research on the coupled movement of water, vapor, and heat during the freezing-thawing period which can, in turn, provide theoretical guidance for rational irrigation practices and ecological protection. In this study, the soil temperature and moisture changes in the deep vadose zone were observed by in-situ monitoring from November 2017 to March 2018 in the Mu Us Desert. The results showed that changes in soil temperatures and temperature gradients were largest in soil layers above the 100-cm depth, and variations decreased with soil depth. The relationship between soil temperature and unfrozen water content can be depicted well by both theoretical and empirical models. Due to gradients of the matric potential and temperature, soil water flowed from deeper soil layers towards the frozen soil, increasing the total water content at the freezing front. The vapor flux, which was affected mainly by temperature, showed diurnal variations in the shallow 20-cm soil layer, and its rate and variations decreased gradually with increasing soil depths. The freeze-thaw process can be divided into three stages: the initial freezing stage, the downward freezing stage, and the thawing stage. The upward vapor flux contributed to the formation of the frozen layer during the freezing process.

Low carbon has become a highly relevant topic in today’s society, particularly for manufacturing enterprises. To gain insight into how manufacturing enterprises embedded in the industrial internet platform make decisions regarding low-carbon technology innovation, this article examines the service quality of the platform, the low-carbon preferences of the manufacturing enterprises, and government subsidy factors. A platform ecological system game model, comprised of a single manufacturing enterprise and an industrial internet platform, is then established. The results indicate that, under the model’s assumptions, the decarbonization of production can only occur when the cost of low-carbon innovation is below a specific threshold. Decentralized decision making is more effective in promoting low-carbon innovation by the manufacturing enterprises when the cost of low-carbon technology innovation is low. The greater the service quality of the industrial internet platform, the stronger the positive influence of the low-carbon preferences of users and government subsidies on the low-carbon innovation level of the manufacturing enterprises. This study offers useful decision-making advice for both the industrial internet platform and the manufacturing enterprises.

In arid areas, vapor flow has been recognized to contribute significantly to the mass and energy transfers and to play a critical role in maintaining surface vegetation and ecosystems. To better understand the continuous spatial and temporal variations in liquid water and water vapor contents under different climatic conditions, soil water contents, temperatures, and micrometeorological variables were observed in-situ in the Mu Us Desert of northwestern China. The collected data were then used to calibrate and validate the Hydrus-1D model simulating either the coupled movement of water, vapor, and energy or only isothermal water flow in soils (the latter as a reference). The results of the coupled model were not only in better agreement with observed data, but also advanced our understanding of underlying mechanisms of soil water flow. For the coupled model, the isothermal liquid flux was the most significant component of the total water flux. Three diurnal stages were identified for thermal liquid and vapor fluxes on dry days, while the vapor flux became almost negligible during rainfall events. The results indicate that isothermal liquid, thermal liquid, and thermal vapor fluxes should be considered simultaneously when evaluating soil water flow in arid regions, while the isothermal vapor flux can be neglected. Vapor flow contributed, on average, about 13% of the total water flux in the uppermost soil layer during the analyzed period at the study area, and this ratio often exceeded 20%.

Objective: This research is aimed to systematically evaluate the efficacy and safety of Chinese plus Western Medicine treatment for Childhood purpuric nephritis by Meta-analysis, in order to improve the cure rate and reduce adverse reactions of this disease, then provide guidance for clinical medication. Methods: There are six major databases including CNKI, Pubmed, Embase, World Wide Database, Web of science and Science Direct retrieved through the Internet, and the randomized-controlled trials of the combined therapy for Childhood purpuric nephritis published both in Chinese and English from the 1999 to October 2019 were collected. Meta-analysis by R software 3.5.0 was adopted to analyze the effective index and adverse effect. Results: In total 92 papers of randomized-controlled clinical studies were enrolled. HSPN children treated with combined therapy demonstrated a significant increase in total effective rate (RR=1.19; 95%CI (1.16–1.21), P

The improvement of the resolution of DNA sequencing by nanopore technology is very important for its real-life application. In this paper, we report our work on using molecular dynamics simulation to study the dependence of DNA sequencing on the translocation time of DNA through a graphene nanopore, using the single-strand DNA fragment translocation through graphene nanopores with diameters down to ∼2 nm as examples. We found that A, T, C, and G could be identified by the difference in the translocation time between different types of nucleotides through 2 nm graphene nanopores. In particular, the recognition of the graphene nanopore for different nucleotides can be greatly enhanced in a low electric field. Our study suggests that the recognition of a graphene nanopore by different nucleotides is the key factor for sequencing DNA by translocation time. Our study also indicates that the surface of a graphene nanopore can be modified to increase the recognition of nucleotides and to improve the resolution of DNA sequencing based on the DNA translocation time with a suitable electric field.

Growth and development are unique physiological phenomena in infants and adolescents. The height and weight are regarded as important indicators of growth and have attracted considerable attention from the family and society. In this paper, the static and dynamic recording and evaluation of children's growth and development were performed. The physical development was evaluated by children's gender, date of birth, weight, and height data under the standard of World Health Organization (WHO). The growth and development curve could be drawn automatically according to the previous growth and development records of the children, and the dynamic tracking management of children's development was attained. This tracking is primarily used to evaluate the level of growth and development of individuals, groups, children and adolescents and provide advice for health care. The system also records the child's growth in the process of dribs and drabs, becoming a child's growth assistant and playmate. This paper mainly introduces the design and construction of the system architecture, technology selection, design and implementation of the database and the realization of the basic functions of the Android.

Due to be difficult for pregnant woman doing a periodic inspection at the hospital, a home uterine contraction pressure monitoring system has been developed, which consists of uterine contraction pressure signal collected unit, wireless transmission unit and PDA module. The system is built based on MCU chip-dsPIC33FJ128MC706. The uterine contraction pressure signal is acquired by load cell sensor is FSL1500N2C made by Honeywell, which can be wireless transmitted to PDA via Bluetooth. The signal can be analyzed real-time on PDA and the diagnosis can be made to prevent premature birth or occurrence of abortion effectively.

Large polarization effects in nitride-based heterostructures provide opportunities for controllably introducing negative charge, equivalent to acceptor-doping, in AlGaN/GaN HBT structures. This paper reviews evidence for polarization-based doping effects in nitride-based materials, and discusses potential applications of these effects for the improvement of p-contacts and p-type base conductivity. It is shown that in conventional HBTs grown with Ga-terminated faces in the emitter-up configuration, the polarization-induced charges detract from the acceptor doping of the base. In contrast, the polarization effects add to effective doping in the base in structures that are grown and processed as collector-up devices, or in devices that are grown emitter-up and utilize the transferred substrate approach.

Coronary Artery Disease (CAD) is a leading type of heart disease in the world caused by the gradual build-up of plaque on the walls of the arteries. Due to CAD’s high incidence rate and mortality, it is very harmful to human health. CAD can develop slowly and silently over years without any symptoms. Early diagnose of CAD is one of the most important medical research areas. Diastolic murmurs that occur as additional components in the heart sound signal provide clinicians with valuable diagnostic and prognostic information about the function of heart valves. When coronary arteries become narrowed or blocked, the turbulence appears which is produced by blood moving across the stenotic arteries. During the relatively quiet diastolic period of the cardiac cycle, the murmurs are likely to be loudest when coronary blood flow is maximal. Initial studies show that diastolic murmurs produced by coronary arterial stenosis contain higher frequency components.

To investigate the therapeutic effect of double fill nine tastes soup in treating children recurrent respiratory infection (RRTI) and the change of immune function.77 RRTI patients were randomly selected into observation and control groups. The observation group was treated with Chinese medicine- double fill nine tastes soup,water frying points 2 times oral. The control was treated with transfer factor oral liquid,every 10 mL,2 times daily oral. Treatment periods were both two months. IgA, IgG, IgM and IL-12, TNF-alpha, INF-gamma were detected before and after treatment to assess the clinical effects and the changes of immune factors, meanwhile, a health group was established.Before treatment, compared with the health group, the serum IgA, IgG, IgM, IgE, IL-12, TNF-alpha, IFN-gamma in both groups were significantly different (P0.01). After treatment, the ratio of IgA, IgG, Ig M, IL-12, TNF-alpha, IFN-gamma in two groups were significantly different (P0.01). Compared with the recurrence rate and clinical effects, the observation group was better than control, and the differences were significant (P0.01).Double fill nine tastes soup has significant effects in treating recurrent respiratory infection (RRI) and enhance the immune function in children.

The piezoelectric polarization and its associated charge density are calculated for edge, screw, and mixed dislocations oriented parallel to the c axis in wurtzite GaN. It is shown that the polarization field generated by screw components of dislocations is divergence free, and thus does not generate electric fields. Edge dislocations produce polarization fields that have nonzero divergence only at interfaces. These characteristics minimize the electrical and optical effects of the dislocations mediated by the piezoelectric effect.

A quantitative characterization of statistical quantization effects in a discrete-time digital system is derived as a function of fixed-point data types. The analysis is based on a perturbation theory approach which assumes the quantization noise is a small deviation from the ideal characteristics and that the system does not contain decision-error propagation. The theory works for both linear and nonlinear digital systems with either stationary or nonstationary inputs. The approach is applied to an LMS adaptive filter in both the transient and steady state periods.

A tool that automates the floating-point to fixed-point conversion (FFC) process for digital signal processing systems is described. The tool automatically optimizes fixed-point data types of arithmetic operators, including overflow modes, integer word lengths, fractional word lengths, and the number systems. The approach is based on statistical modeling, hardware resource estimation and global optimization based on an initial structural system description. The basic technique exploits the fact that the fixed point realization is a weak perturbation of the floating point realization which allows the development of a system model which can be used in the optimization process.

High level modeling tools make it possible to synthesize a high performance FPGA design directly from a Simulink model. Accurate estimates of the FPGA resources required provides the system designer important feedback on area and cost, which is valuable even during early design iterations. Previous approaches to hardware resource estimation suffer a combination of inaccuracy, slowness, and/or high complexity, which limits their practicality at the algorithm definition stage. We address these restrictions with a fast resource estimation tool incorporated in the Xilinx System Generator. Implemented using MATLAB code, the estimator run time is proportional to the Simulink compilation time, and typically takes from seconds to minutes depending upon the size of the Simulink model. Estimates are conservative, and accurate to within 10% of the post-mapping implementation report. In this paper, we explain how block resource information is characterized in a MATLAB function. This characterization also estimates logic that will be trimmed during synthesis and mapping. Finally, we describe how these estimation functions are integrated within Simulink in a user-friendly and automated infrastructure. This approach has been incorporated in System Generator since version 3.1.