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Copyright of Nefrologia is the property of Revista Nefrologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Smarter teaching has been widely popularized in computer teaching in higher education institutions as a key part of modern education. However, this practice faces some problems, such as excessive learning content, a tight teaching schedule, low learning enthusiasm among students, and limited time for practice. These shortcomings can be addressed by incorporating smarter teaching. A computer course in an engineering college was taken as an example in this study to construct a new mode for computer teaching based on deep learning theory, which includes five teaching stages, namely: introduction of new knowledge, pre-testing of knowledge, discussion of knowledge, task-oriented training, and post-testing of knowledge. An intelligent test database was constructed for computer teaching to be carried out under the guidance of the bidirectional encoder representation from transformers (BERT)-based textual analysis approach. Results show that (1) the test database constructed using the BERT-based textual analysis approach is more scientific and effective than other databases. (2) When validated on relevant teaching information and materials, the proposed approach improves students' learning enthusiasm, problem-solving ability, and practicing capability. (3) The smarter teaching mode constructed based on deep learning theory can significantly improve the quality of course teaching and enhance students' professional skills. The conclusions provide necessary technical support for the construction of computer-targeted test databases, which are conducive to pushing the reform and development of smarter teaching in computer science. [ABSTRACT FROM AUTHOR]

In order to enhance system energy efficiency, bidirectional link resource allocation strategy in GFDM-based multiuser SWIPT systems is proposed. In the downlink channel, each SWIPT user applies power splitting (PS) receiver structure in information decoding (ID) and non-linear energy harvesting (EH). In the uplink channel, information transmission power is originated from the harvested energy. An optimization problem is constructed to maximize weighted sum ID achievable rates in the downlink and uplink channels via bidirectional link power allocation as well as subcarriers and subsymbols scheduling. To solve this non-convex optimization problem, Lagrange duality method, sub-gradient-based method and greedy algorithm are adopted respectively. Simulation results show that the proposed strategy is superior to the fixed subcarrier scheme regardless of the weighting coefficients. It is superior to the heuristic algorithm in larger weighting coefficients scenario. [ABSTRACT FROM AUTHOR]

Applications of high amounts of nitrogen (N) fertilizer are essential for obtaining sustainable maize (Zea mays L.) yields but also result in low N-use efficiency (NUE) and cause a series of environmental problems. To optimize fertilizer management, it is necessary to determine the effects of soil fertility improvement on NUE and the fate of N fertilizer. In this study, we conducted a 15N tracer pot experiment involving five different fertilizer treatments in soils with five different total organic carbon levels under field conditions. The average NUE ranged from 36 to 56% 15N-urea and 0.1 to 0.2% residual N in the first and second seasons. The N retained in the soil ranged from 10 to 28%, and the N lost to water and the atmosphere ranged from 29 to 39% in the five soils. Compared with that in the low-fertility soils, NUE in the high-fertility soils was 20-45% greater, and N loss was 1-6% lower. The results showed that higher soil fertility corresponded to higher NUE and lower N loss. We suggest that although the local customary N fertilizer application rate (N3; 165 kg N/ha) in the study area is reasonable for low-fertility soils, after soil fertility improvements, an approximately 50% reduction of N fertilizer should be implemented. [ABSTRACT FROM AUTHOR]

Polybutylene succinate (PBS) fiber is a kind of synthetic fibers with excellent properties and biodegradability, which has been produced on a large scale in China. To investigate the application properties of PBS fibers, the structure and properties were systematically studied in this paper. The microstnictures and thermal properties of PBS fibers were analyzed by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), thermo gravimetric (TG) and differential scanning calorimeti (DSC). The mechanical properties, chemical stability and dyeing properties of PBS fibers were also studied. The results show that PBS fibers are a-ciystalline with a crystallinity of 58.56%. PBS fibers have an excellent thermal stability and the initial temperature of thermal degradation is 370 "C. The tensile strength, the elongation at break, the elastic recovery rate at a fixed elongation (5%) and the moisture regain rate of PBS fibers are 29.57 cN/tex,90.94%,44.55% and 5.04%, respectively. The chemical stability is as follows: alkaU resistance < acid resistance < oxidation resistance. PBS fibers have an excellent dye uptake by carrier dyeing of disperse dyes. [ABSTRACT FROM AUTHOR]

Computer Image Processing is a foundation course of computer specialty. Due to the problem of teaching method and students' ability problem, the teaching process is boring and students are absent-minded in class, thus leading to low teaching efficiency of Computer Image Processing and low teaching quality. As well, the learning effect and level cannot meet the requirement of market and society. On this basis, Computer Image Processing was chosen as the teaching case to construct ecological learning space mode meeting the course requirements on the basis of investigative study and under the guidance of interactive theory. Besides, the students of computer major were chosen as the objects of study for one-semester teaching practice. Questionnaire survey and interview were combined for empirical research in order to innovate for teaching mode of Computer Image Processing and provide higher-quality computer talents for the society. The investigation found that the teaching mode is well welcomed by students and greatly improves their learning initiative and learning effect. [ABSTRACT FROM AUTHOR]

Carboxymethyl cellulose (CMC) hydrogel fibers were prepared via a solution spinning method with aluminum sulfate as the crosslinking agent. The preparation process of the CMC hydrogel fibers was optimized via orthogonal experiments. FTIR, POM, SEM and TGA were used to characterize the structure and properties of the hydrogel fibers. The mechanical properties and absorption ability of the hydrogel fibers were also investigated. The results indicated that an even structure was formed in the hydrogel. The mechanical properties of the hydrogel fibers were improved with increasing CMC degree of substitution. The hydrogel fibers had excellent moisture absorption performance, and are well-suited for biomedical applications such as wound dressings. [ABSTRACT FROM AUTHOR]

The structural responses are often used to identify the structural local damages. However, it is usually difficult to gain the responses of the track, as the sensors cannot be installed on the track directly. The vehicles running on a track excite track vibration and can also serve as response receivers because the vehicle dynamic response contains the vibration infonnation of the track. A damage identification method using the vehicle responses and sensitivity analysis is proposed for the vehicletrack coupling system in this paper. Different from most damage identification methods of vehicle-track coupling system, which require the structural responses, only the vehicle responses are required in the proposed method. The local damages are identified by a sensitivity-based model updating process. In the vehicle-track coupling system, the track is modeled as a discrete point supported Euler-Bemoulli beam, and two vehicle models are proposed to investigate the accuracy and efficiency of damage identification. The measured track irregularity is considered in the calculation of vehicle dynamic responses. The measurement noises are also considered to study their effects to the damage identification results. The identified results demonstrate that the proposed method is capable to identity the local damages of the track accurately in different noise levels with only the vehicle responses. [ABSTRACT FROM AUTHOR]

This paper reports the development of a theoretically rigorous method for permanent way engineers to assess the condition of railway ballast under a concrete sleeper with the potential to be extended to a smart system for long-term health monitoring of railway ballast. Owing to the uncertainties induced by the problems of modeling error and measurement noise, the Bayesian approach was followed in the development. After the selection of the most plausible model class for describing the damage status of the rail-sleeper-ballast system, Bayesian model updating is adopted to calculate the posterior PDF of the ballast stiffness at various regions under the sleeper. An obvious drop in ballast stiffness at a region under the sleeper is an evidence of ballast damage. In model updating, the model that can minimize the discrepancy between the measured and model-predicted modal parameters can be considered as the most probable model for calculating the posterior PDF under the Bayesian framework. To address the problems of non-uniqueness and local minima in the model updating process, a two-stage hybrid optimization method was developed. The modified evolutionary algorithm was developed in the first stage to identify the important regions in the parameter space and resulting in a set of initial trials for deterministic optimization to locate all most probable models in the second stage. The proposed methodology was numerically and experimentally verified. Using the identified model, a series of comprehensive numerical case studies was carried out to investigate the effects of data quantity and quality on the results of ballast damage detection. Difficulties to be overcome before the proposed method can be extended to a long-term ballast monitoring system are discussed in the conclusion. [ABSTRACT FROM AUTHOR]

Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Veterinary Research / Revue Canadienne de Recherche Vétérinaire is the property of Canadian Veterinary Medical Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Coronary artery disease (CAD) is a multifactorial disease with a genetic component. Pigment epitheliumderived factor (PEDF) exerts anti-inflammatory, anti-oxidant, anti-thrombotic, and anti-angiogenic effects and thus has received increasing attention as a sensitive biomarker of atherosclerosis and CAD. To explore the potential association between PEDF single nucleotide polymorphisms (SNPs) and CAD, we performed this case-control study of consecutive elderly Chinese Han male patients (n = 416) and age-matched male controls (n = 528) without a history of CAD or electrocardiographic signs of CAD. The enrolled CAD patients (age ≥ 60 years) are not biologically related. A tag approach was used to examine 100% of common variations in the PEDF gene (r2 ≥ 0.8, minor allele frequency > 0.1). PEDF tag SNPs (tSNPs) were selected using the HapMap Data-CHB which describes the common patterns of human DNA sequence variation and Tagger program. SNPs were genotyped using ligase detection reaction (LDR). Seven tSNPs (rs8075977, rs11658342, rs1136287, rs12603825, rs12453107, rs6828 and rs11078634) were selected. Among them, only one SNP, rs8075977 (C/T) located in the 5'-flanking region, showed the significant effect on the susceptibility to CAD. The frequency of its T allele was significantly higher in the controls (52.7%) than that in the CAD group (46.2%) (adjusted OR = 0.88, 95% CI: 0.80-0.96; P = 0.005). In conclusion, the T allele of rs8075977 in the 5'-flanking region of the PEDF gene may be protective for CAD. Conversely, the C allele at this variation site is associated with CAD in elderly Chinese Han men. [ABSTRACT FROM AUTHOR]

This paper analyzes the secrecy performance of an amplify-and-forward (AF) relay network, where a multi-antenna eavesdropper attempts to overhear the transmitted message from a multi-antenna source to a multi-antenna destination with a single antenna relay. Firstly, we derive the approximate analytical expressions for the secrecy outage probability (SOP) and average secrecy rate (ASR) of the relay network. Then, asymptotic expressions of SOP and ASR at high main-to-eavesdropper ratio (MER) are also provided to reveal the diversity gain of the secure communication. Finally, numerical results are given to verify the theoretical analysis and show the effect of the number of antennas in the considered relay network. [ABSTRACT FROM AUTHOR]

Large corn ethanol factory had the characteristics which discharged high concentration organic wastewater. According to that, it chose a suitable technology of wastewater treatment, to ensure water quality index and achieve the national discharge standard, to implement the operation of equipment continuously and steadily. This paper introduced specific process of wastewater treatment and characteristics of the process, analysed the economic costs and benefits in the process of running. [ABSTRACT FROM AUTHOR]

A novel poly(4-iodobutoxylmethylsiloxane) (PIBMS) water repellent with high reaction activity was synthesized using poly(hydromethylsiloxane) (PHMS), methyl iodide (MeI) and tetrahydrofuran (THF) in the presence of a catalytic amount of PdCl2. The new chemical active group of PIBMS could covalently bond to the cotton fabric. It is conducive to improve the washability of treated cotton fabric. The structure of PIBMS was confirmed by the FT-IR and ¹H NMR spectra. The PIBMS was applied onto cotton fabric by a pad-dry-cure process. PIBMS was applied to cotton fabrics and the effect of the process parameters on water repellent performance was studied. The morphology of PIBMS polymer film on the cotton fabric was investigated by SEM. The water repellency of treated cotton fabrics before and after vigorous washes was compared. The results show that the water repellent grade of cotton fabric treated with PIBMS was 90. The contact angle of the treated cotton fabric was 136.94°, which was higher than that of the untreated cotton fabric. The water repellent grade of treated cotton fabric was still as high as 80 after 20 times washing. The tear strength and the tensile strength of cotton fabric significantly increased after PIBMS treatment. The air permeability and the water vapor permeability of treated cotton fabric were slightly lower than those of untreated cotton fabrics. [ABSTRACT FROM AUTHOR]

To establish the HPLC method to examine plasma concentration of lamotrigine and oxcarbazepine. This study set chlorzoxazone as the internal standard, chromatographic column was Column C18 (200x4.6mm, 5um) of DIKMA company, the mobile phase was methanol, water and trifluoroacetic acid, with rate of 40: 60: 0.0005, at a flow rate of 1 mllmin-1, the detected wavelength was 240 nm. The plasma concentrations of lamotrigine was 0.5-50µg⋅mL-1, the standard curve was excellent for Y=0.5511C-0.5669, r=0.9940, average recovery was 91.40%; The plasma concentrations of oxcarbazepine was 0.5-50µg⋅mL-1, the standard curve was good for Y=0.4026C-0.5895, r=0.9925 and the average recovery was 89.59%; The three plasma concentrations of lamotrigine were respectively 25µg⋅mL-1, 10 µg⋅mL-1 and 2µg⋅mL-1 and its five parallel sample for injection RSD were respectively 4.01%, 6.15% and 4.64%; The three plasma concentration of oxcarbazepine were 25µg⋅mL-1, 10µg⋅mL-1 and 2µg⋅mL-1, and its five parallel sample for injection RSD were respectively 3.05%, 4.27% and 9.01%. This method was easy to operate, high recovery and high precision, and was applicable to the clinical detection for plasma concentration of lamotrigine and oxcarbazepine. [ABSTRACT FROM AUTHOR]

Background Due to their biocompatibility and bioactivity, dicalcium silicate (C 2 S) and hydroxyapatite (HA) are used as coating materials for prosthetic orthopedic and dental implants or as bone substitute materials to fill bone defects. However, prostheses and bone substitutes can release particles that trigger an immune response in the recipient. The immunological effects of C 2 S particles have not yet been studied. Objective The aim of this study was to determine the cytotoxic effects of C 2 S particles on primary human monocytes, a human monocyte cell line (THP-1) and an osteoblast-like cell line (MG-63). The proinflammatory effects of C 2 S particles on THP-1 were also detected. Moreover, the osteogenic effects of C 2 S and HA on MG-63 cells were investigated. Methods Characterization of C 2 S and HA was performed using scanning electron microscopy (SEM), energy dispersive analysis (EDS), X-ray diffraction (XRD), Brunner–Emmett–Teller (BET) measurements and laser diffraction. The cytotoxic effect of C 2 S on primary human monocytes as well as THP-1 and MG-63 cells was measured using Trypan blue assays, Cell Counting Kit-8 (CCK-8) assays and flow cytometry to detect apoptosis. THP-1 human monocytes with or without lipopolysaccharide (LPS) stimulation were exposed to C 2 S and HA for 6 and 24 h. Thereafter, the mRNA expression and protein concentrations of MMP-2, MMP-9, TIMP-2, TIMP-1 and TNF-α were evaluated using real-time PCR and ELISA, respectively. RANKL and OPG mRNA expression levels in MG-63 cells were examined using real-time PCR. Results No significant cytotoxicity was recorded when cells were directly cultured with C 2 S/HA particles. After THP-1 cells were cultured with C 2 S/HA for 24 h, MMP-2, MMP-9 and TNF-α expression increased, whereas TIMP-2 and TIMP-1 expression decreased. Compared with HA, C 2 S slightly increased MMP-9 expression and slightly decreased TIMP-1 expression. The MMP: TIMP ratio increased in the C 2 S and HA groups; however, HA significantly increased the MMP-9: TIMP-1 ratio compared with C 2 S. Compared with HA, C 2 S caused less TNF-α production. C 2 S/HA did not modify the expression of proinflammatory mediators in LPS-stimulated cells. Furthermore, C 2 S/HA significantly increased OPG expression and slightly increased RANKL expression in MG-63 cells. C 2 S and HA decreased the RANKL: OPG ratio. Conclusion Our in vitro data suggest that C 2 S is relatively safe when directly cultured with cells. In addition, C 2 S may exert proinflammatory effects; however, compared with HA, C 2 S had fewer proinflammatory effects on THP-1. C 2 S and HA did not alter the LPS-induced production of proinflammatory mediators and had similar osteogenic effects on MG-63 cells. [ABSTRACT FROM AUTHOR]

This paper proposed a discrete wavelet transform based method for time-varying physical parameter identification of shear type structures. The time-varying physical parameters are dispersed and expanded at multi-scale as profile and detail signal using discrete wavelet basis. To reduce the number of unknown quantity, the wavelet coefficients that reflect the detail signal are ignored by setting as zero value. Consequently, the time-varying parameter can be approximately estimated only using the scale coefficients that reflect the profile signal, and the identification task is transformed to an equivalent time-invariant scale coefficient estimation. The time-invariant scale coefficients can be simply estimated using regular least-squares methods, and then the original time-varying physical parameters can be reconstructed by using the identified time-invariant scale coefficients. To reduce the influence of the ill-posed problem of equation resolving caused by noise, the Tikhonov regularization method instead of regular least-squares method is used in the paper to estimate the scale coefficients. A two-story shear type frame structure with time-varying stiffness and damping are simulated to validate the effectiveness and accuracy of the proposed method. It is demonstrated that the identified time-varying stiffness is with a good accuracy, while the identified damping is sensitive to noise. [ABSTRACT FROM AUTHOR]

This paper investigates the option pricing under the FMLS (finite moment log stable) model, which can effectively capture the leptokurtic feature observed in many financial markets. However, under the FMLS model, the option price is governed by a modified Black-Scholes equation with a spatial-fractional derivative. In comparison with standard derivatives of integer order, the fractional-order derivatives are characterized by their "globalness", i.e., the rate of change of a function near a point is affected by the property of the function defined in the entire domain of definition rather than just near the point itself. This has added an additional degree of difficulty not only when a purely numerical solution is sought but also when an analytical method is attempted. Despite this difficulty, we have managed to find an explicit closed-form analytical solution for European-style options after successfully solving the FPDE (fractional partial differential equation) derived from the FMLS model. After the validity of the put-call parity under the FMLS model is verified both financially and mathematically, we have also proposed an efficient numerical evaluation technique to facilitate the implementation of our formula so that it can be easily used in trading practice. [ABSTRACT FROM AUTHOR]

Semi-rigid base materials have been widely used in recent years. However, this material is easy to crack, which adversely affects the performance of the pavement. In this paper, an innovative reclaimed phosphogypsum-based material is used as an anti-cracking agent added in the semi-rigid base. Several laboratory tests and field observations have been taken to evaluate the potential of the material that we are proposing to be used as an anti-cracking agent. The shrinkage tests show that the shrink space of the road base caused by the variations of the temperature and humidity has decreased dramatically because of the involvement of the anti-cracking agent. The influence of the delay on the molding time and on the strength of gravel mixtures is also analyzed, and the results show that the anti-cracking agent has a slow setting performance. By adding an anti-cracking agent into the semi-rigid base material, early strength of the material is enhanced, curing period is shortened, and lasting quality is improved. The continuous construction of the base and asphalt pavement are technically feasible in the testing road because of the excellent expansion, densification, and water-resistance characteristics of the anti-cracking agent. As a result, cracks in the pavement can be retarded or lightened, and, thus, the pavement service life can be extended. [ABSTRACT FROM AUTHOR]