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To study the feasibility of dolomite replacing traditional marble calcium carbonate in the preparation of composites, the composition, surface and particle size of dolomite and marble were determined, and the mechanical properties of high-density polyethylene (HDPE) filled with two powders were compared. The results showed that the dolomite powder had smaller particle size, narrower particle size distribution and more regular particle shape than marble powder under the same crushing conditions. The impact strength of dolomite/HDPE composites (18.12 kJ/m²) was higher than that of marble/HDPF composites (8.60 kJ/m²). The modification effects of different modifiers on dolomite and the mechanical properties of modified dolomite/HDPE composites were investigated by FTIR, SEM and universal mechanical testing machine. The results showed that the compatibility between dolomite and HDPE matrix was improved when the stearic acid and coupling agent were used, and the impact strength, flexural strength and tensile strength of the composites increased by 71.08%, 7.40% and 6.43%, respectively, compared with the unmodified dolomite composites. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the relationship between obstructive sleep apnea hypopnea syndrome (OSAHS) severity and fat, bone, and muscle indices. Methods: This study included 102 patients with OSAHS and retrospectively reviewed their physical examination data. All patients underwent polysomnography, body composition analysis, dual-energy X-ray absorptiometry, computed tomography (CT) and blood test. Correlation and multiple linear regression analyses were performed using SPSS 22.0. Results: Among the fat indices, fat mass (FM) (r = 0.27–0.43), body fat percentage (BFP) (r = 0. 25–0.35), visceral fat area (VFA) (r = 0.28–0.40) and trunk fat mass (TFM) (r = 0.26–0.34) were positively correlated with hypopnea index (HI), apnea-hypopnea index (AHI), oxygen desaturation index (ODI), and percent of time spent with oxygen saturation below 90% (T90%), respectively, and negatively correlated with mean pulse oxygen saturation (SpO2) (r= -0.28–-0.41). For bone indexes, T8, T9, T11, L1-CT value, mean vertebral CT value and 25-Hydroxyvitamin D3 were positively correlated with mean SpO2 (r = 0.23–0.32), respectively. For muscle indexes, pectoralis muscle density (PMD) was negatively correlated with HI, AHI, and ODI (r= -0.20–-0.36) and positively correlated with mean SpO2 (r = 0.26). In separate models predicting sleep measures, AHI increased by 0.36, 0.29, 0.34 and 0.25 events/h per unit increase in FM, BFP, VFA, and triglyceride (TG), respectively. AHI decreased by 0.27 per unit increase in PMD. T90% increased with FM, BFP, VFA, WHR, TG and total cholesterol (TC), but decreased with appendicular skeletal muscle mass (ASM) and PMD respectively. Conclusion: Higher fat levels and lower vertebral CT values, muscle mass and density correlated with a higher degree of OSAHS severity. Intermittent hypoxia may affect fat, bone, and muscle metabolism in patients with OSAHS. [ABSTRACT FROM AUTHOR]

A mounting body of evidences suggests that patients with chronic heart failure (HF) frequently experience cognitive impairments, but the neuroanatomical mechanism underlying these impairments remains elusive. In this retrospective study, 49 chronic HF patients and 49 healthy controls (HCs) underwent brain structural MRI scans and cognitive assessments. Cortical morphology index (cortical thickness, complexity, sulcal depth and gyrification) were evaluated. Correlations between cortical morphology and cognitive scores and clinical variables were explored. Logistic regression analysis was employed to identify risk factors for predicting 3‐year major adverse cardiovascular events. Compared with HCs, patients with chronic HF exhibited decreased cognitive scores (p <.001) and decreased cortical thickness, sulcal depth and gyrification in brain regions involved cognition, sensorimotor, autonomic nervous system (family‐wise error correction, all p values <.05). Notably, HF duration and New York Heart Association (NYHA) demonstrated negative correlations with abnormal cortex morphology, particularly HF duration and thickness in left precentral gyrus (r = −.387, p =.006). Cortical morphology characteristics exhibited positive associations with global cognition, particularly cortical thickness in left pars opercularis (r =.476, p <.001). NYHA class is an independent risk factor for adverse outcome (p =.001). The observed correlation between abnormal cortical morphology and global cognition suggested that cortical morphology may serve as a promising imaging biomarker and provide insights into neuroanatomical underpinnings of cognitive impairment in patients with chronic HF. [ABSTRACT FROM AUTHOR]

Background: Fecal carriage of extended-spectrum β-lactamase-producing Escherichia coli (ESBL-EC) and carbapenemase-producing E. coli (CP-EC) is well reported among hospitalized adults and children. However, there are few studies on the carriage prevalence and ESBL-EC and CP-EC genotypes among healthy children in China. Patients and Methods: Stool samples were collected from 330 students in 2021 from three randomly selected primary schools in Changsha, China. ESBL-EC and CP-EC were screened using CHROMagarTM chromogenic plates. ESBL and carbapenemase production was confirmed using the double-disc synergy test and a modified carbapenem inactivation method, respectively. Antimicrobial susceptibility was tested using the broth microdilution method. Resistance determinants, virulence factors, and phylogenetic groups were determined by PCR and sequencing. Multi-locus sequence typing (MLST) was performed (seven housekeeping genes were amplified and sequenced) on the phylogenic group B2 E. coli to detect high-risk clonal strains such as ST131 E. coli. Then, ST131 E. coli were characterized based on ST131 clades, O-type, and fimH alleles. Results: In total, 118 (35.8%) ESBL-EC and 3 (0.9%) CP-EC were isolated. blaCTX-M was the most common genotype (27.1%), identified in all ESBL-EC, except one, which carried blaSHV-12. One isolate with mcr-1 was found amongst ESBL-EC, whereas all three CP-EC carried blaNDM-1. The predominant sequence type (ST) clones in group B2 were ST131 and ST1193. The prevalence of ST131 E. coli was 9.9%, displaying serotypes O16 and O25b, fimH alleles 30, 41, and 89, and ST131 clades A and C1-M27. Conclusion: In this study, high carriage rate of ESBL-EC was found among healthy children, and the dominant ESBL was CTX-M-14. In addition, high-risk clones (ST131 and ST1193) were also detected. This emphasizes the importance of monitoring ESBL-EC in community settings. [ABSTRACT FROM AUTHOR]

Background: Information on the prevalence and resistance spectrum of nontuberculous mycobacteria (NTM) in China is mainly based on regional or local data. To estimate the proportion of NTM cases in China, a national survey of NTM pulmonary disease was carried out based on acid-fast positive sputum samples collected in 2013. Methods: Sputum samples collected from enrolled presumptive cases in 72 nationwide tuberculosis surveillance sites from the 31 provinces in the mainland of China were cultured using L-J medium at the National tuberculosis reference laboratory (NTRL). MALDI-TOF MS identified the species of re-cultured strains, and minimal inhibitory concentrations (MICs) were determined to evaluate the drug susceptibility of NTM isolates. Data analysis used statistical software SPSS version 22.0 for Windows statistical package. Results: Of 4917 mycobacterial isolates cultured, 6.4% [317/4917, 95% confidence interval (CI) 5.8%–7.2%] were confirmed as NTM, among which 7.7% (287/3709, 95% CI 6.9%–8.6%) were from the southern region. In inland and coastal China, 87.7% (95% CI 78.7%–93.2%) and 50.0% (95% CI 43.7%–56.3%) of isolates, respectively, were slow-growing mycobacteria (SGM), with the remaining rapid growing mycobacteria (RGM). A total of 29 species were detected, Mycobacterium abscessus had higher clarithromycin-inducible resistance rates than M. massiliense (65.67% vs 2.22%). M. kansasii presented lower resistance rates in linezolid and moxifloxacin than M. avium-intracellulare complex (3.23% vs 66.67%, 0 vs 47.22%) and other SGM (3.23% vs 38%, 0 vs 26%). Conclusions: More NTM pulmonary disease was observed in the south and coastal China (P < 0.01). SGM was widely distributed, and more RGM are present in southern and coastal China (P < 0.01). The antimicrobial resistance spectrum of different NTM species was significantly different and accurate species identification would be facilitated to NTM pulmonary disease treatment. [ABSTRACT FROM AUTHOR]

Background: Malaria and neglected communicable protozoa parasitic diseases, such as leishmaniasis, and trypanosomiasis, are among the otherwise called diseases for neglected communities, which are habitual in underprivileged populations in developing tropical and subtropical regions of Africa, Asia, and the Americas. Some of the currently available therapeutic drugs have some limitations such as toxicity and questionable efficacy and long treatment period, which have encouraged resistance. These have prompted many researchers to focus on finding new drugs that are safe, effective, and affordable from marine environments. The aim of this review was to show the diversity, structural scaffolds, in-vitro or in-vivo efficacy, and recent progress made in the discovery/isolation of marine natural products (MNPs) with potent bioactivity against malaria, leishmaniasis, and trypanosomiasis. Main text: We searched PubMed and Google scholar using Boolean Operators (AND, OR, and NOT) and the combination of related terms for articles on marine natural products (MNPs) discovery published only in English language from January 2016 to June 2020. Twenty nine articles reported the isolation, identification and antiparasitic activity of the isolated compounds from marine environment. A total of 125 compounds were reported to have been isolated, out of which 45 were newly isolated compounds. These compounds were all isolated from bacteria, a fungus, sponges, algae, a bryozoan, cnidarians and soft corals. In recent years, great progress is being made on anti-malarial drug discovery from marine organisms with the isolation of these potent compounds. Comparably, some of these promising antikinetoplastid MNPs have potency better or similar to conventional drugs and could be developed as both antileishmanial and antitrypanosomal drugs. However, very few of these MNPs have a pharmaceutical destiny due to lack of the following: sustainable production of the bioactive compounds, standard efficient screening methods, knowledge of the mechanism of action, partnerships between researchers and pharmaceutical industries. Conclusions: It is crystal clear that marine organisms are a rich source of antiparasitic compounds, such as alkaloids, terpenoids, peptides, polyketides, terpene, coumarins, steroids, fatty acid derivatives, and lactones. The current and future technological innovation in natural products drug discovery will bolster the drug armamentarium for malaria and neglected tropical diseases. [ABSTRACT FROM AUTHOR]

Different reaction conditions on the conversion of lignin and monophenol yield were investigated under the catalysis of (5% Mo)-Al2O3-ZrO2; the maximum conversion rate (78.9%) and monophenol yield (31.9%) were observed at 350 °C and 0.2 g catalyst using iso-propanol, in 45 min. The GC–MS analysis revealed that the main alkyl-substituted phenols are 4-ethyl-phenol (17.7%), 4-methyl-phenol (2.303%), phenol (1.878%), etc. The 1H NMR and FT-IR results indicated the presence of alkyl-substituted phenols in liquefaction products, and the formation mechanism of alkyl-substituted phenols was also proposed. [ABSTRACT FROM AUTHOR]

To suppress the inrush current and overshoot voltage generated at the start-up stage of Buck–Boost converter, a digital–controlled soft-start circuit based on digital-to-analog converter (DAC) control technology is proposed in this paper. The power consumption of the circuit is zero and the circuit is also keeps the characteristics of simple structure and high reliability. The circuit has been integrated into a Buck–Boost converter with negative voltage output by using the 0.18 μ m CDMOS high voltage process. The experimental results show that this circuit can effectively suppress the rush current, and the output voltage drops smoothly from 0 to the adjustment value, − 4 V. [ABSTRACT FROM AUTHOR]

To reduce the excessive power consumption and eliminate the battery voltage imbalance caused in conventional method, a novel broken line detection scheme for Li‐ion battery protection integrated circuits (ICs) is presented in this study. The main part of the proposed circuit consists of pull‐up, pull‐down current source, source‐driven MOS, a control switch and a bias current source. A narrow pulse control signal is adopted to trigger broken line detection periodically so as to suppress the detection current consumption, while the disadvantage of battery voltage imbalance is overcome. The proposed circuit has been implemented in a seven cells Li‐ion battery protection IC with 0.18 µm 45 V bipolar‐CMOS‐DMOS process successfully. The experimental results confirm that the chip can reliably detect the disconnections of Li‐ion batteries and take protective measures in a wide cell voltage range from 2.2 to 4.2 V. Furthermore, based on the derivation in this study, the proposed technique can significantly reduce the detection current consumption of each cell, which is well beneficial for low power consumption and battery voltage balance. [ABSTRACT FROM AUTHOR]

We present a method of discriminant diffusion maps analysis (DDMA) for evaluating tool wear during milling processes. As a dimensionality reduction technique, the DDMA method is used to fuse and reduce the original features extracted from both the time and frequency domains, by preserving the diffusion distances within the intrinsic feature space and coupling the features to a discriminant kernel to refine the information from the high-dimensional feature space. The proposed DDMA method consists of three main steps: (1) signal processing and feature extraction; (2) intrinsic dimensionality estimation; (3) feature fusion implementation through feature space mapping with diffusion distance preservation. DDMA has been applied to current signals measured from the spindle in a machine center during a milling experiment to evaluate the tool wear status. Compared with the popular principle component analysis method, DDMA can better preserve the useful intrinsic information related to tool wear status. Thus, two important aspects are highlighted in this study: the benefits of the significantly lower dimension of the intrinsic features that are sensitive to tool wear, and the convenient availability of current signals in most industrial machine centers. [ABSTRACT FROM AUTHOR]

Sugarcane bagasse was refined into cellulose, hemicellulose, and lignin using an ethanol-based organosolv technique. The hydrothermal carbonization (HTC) reactions were applied for bagasse and its two components cellulose and lignin. Based on GC-MS analysis, 32 (13+19) organic byproducts were derived from cellulose and lignin, more than the 22 byproducts from bagasse. Particularly, more valuable catechol products were obtained from lignin with 56.8% share in the total GC-MS integral area, much higher than the 2.263% share in the GC-MS integral areas of bagasse. The organic byproducts from lignin make up more than half of the total mass of lignin, indicating that lignin is a chemical treasure storage. In general, bio-refinery and HTC are two effective techniques for the valorization of bagasse and other biomass materials from agriculture and forest industry. HTC could convert the inferior biomass to superior biofuel with higher energy quantity of combustion, at the same time many valuable organic byproducts are produced. Bio-refinery could promote the HTC reaction of biomass more effective. With the help of bio-refinery and HTC, bagasse and other biomass materials are not only the sustainable energy resource, but also the renewable and environment friendly chemical materials, the best alternatives for petroleum, coal and natural gas. [ABSTRACT FROM AUTHOR]

According to the soft seam, low permeability, low borehole completed rate of the gas drainage borehole drilled and other problems of the soft and outburst seam, a technology of screen pipe putting down along full length borehole for gas drainage was developed. The technology was applied to the site experiment in Pingmei No. 10 and Xinji No. 1 Mine. The results showed the screen pipe putting rate for the technology of screen pipe putting down along full length borehole was over 97%.In comparison with the conventional drilling rod withdrawing and open hole technology, the average concentration of gas drainaged from a single borehole in Pingmei No. 10 mine increased by over two times and the average quantity of gas drainaged from a single borehole could increase by 3.5 times. In comparison with the normal drilling rod withdrawing and screen pipe putting down technology, the concentration of gas drainaged in Xinji No. 1 Mine was increased by one time nearly and the expected effect was reached. [ABSTRACT FROM AUTHOR]

Research has established a relationship between willingness to pay to price premium and brand equity, however, most studies used stated preference data, which are hypothetical situations. Although the experimental auction methodology has been well documented in the previous literature, its application in understanding brand equity has been minimal. The purpose of the study was to determine the relationship between brand equity and consumers' willingness to pay a price premium for branded apparel products using revealed preference methodology. In order to determine the relationship, the Becker- Degroot- Marshack experimental auction mechanism was used with the endow-and-upgrade approach followed with a survey. The survey included 10 multidimensional brand equity questions adopted from the Yoo and Donthu brand equity scale, demographics, previous brand experiences, importance of apparel product attributes and beliefs about brands. The experiment resulted in 100 usable observations. Brand equity was analysed using a composite score on the multidimensional brand equity measurement ( Yoo and Donthu), willingness to pay a price premium was analysed using descriptive statistics and Tobit regression analysis was used to analyse the relationship between brand equity and the willingness to pay a price premium. Findings indicated that the overall brand equity score, a belief that there are more choices in branded merchandise and the importance of brand in making clothing purchase decisions had a modest positive and significant influence on the willingness to pay a price premium. The higher the brand equity, the higher the importance of brands in making clothing purchase decisions, and belief that there are more choices in branded merchandise, the higher the price premium a consumer was willing to pay. [ABSTRACT FROM AUTHOR]

Vehicle traveling time prediction is an important part of the research of intelligent transportation system. By now, there have been various kinds of methods for vehicle traveling time prediction. But few consider both aspects of time and space. In this paper, a vehicle traveling time prediction method based on grey theory (GT) and linear regression analysis (LRA) is presented. In aspects of time, we use the history data sequence of bus speed on a certain road to predict the future bus speed on that road by GT. And in aspects of space, we calculate the traffic affecting factors between various roads by LRA. Using these factors we can predict the vehicle’s speed at the lower road if the vehicle’s speed at the current road is known. Finally we use time factor and space factor as the weighting factors of the two results predicted by GT and LRA respectively to find the final result, thus calculating the vehicle’s traveling time. The method also considers such factors as dwell time, thus making the prediction more accurate. [ABSTRACT FROM AUTHOR]

The phenomenon of EME and charge accumulation were included during the load-bearing failure processing of the rock. The mechanism and signal law of the two kinds of phenomenon through the experiment, as well as the mutual relation of the two kinds of phenomenon, were contribute to monitor the regulation of the mine rock and prevent the dynamic disasters of the mine. There were two charge sensors, one electromagnetic radiated sensors and one pressure sensor in the experiment to detect the EME signal and the charge intensity signal during the load-bearing failure processing of the rock. The results show that the charge intensity signal is prior to the EME signal through the date processing and numerical analysis. The two signals change obviously before the rock crush. The two kinds of phenomenon are homogenous and have obvious master-slave characteristic. With the appeared of the EME signal, the charge intensity signal decreased, the power is released. [ABSTRACT FROM AUTHOR]

This paper introduces a novel robot for outer surface inspection of boiler tubes. The paper describes the hardware system, wireless communication strategy, communication procedure and system software of the robot. The WLAN technology is used in the robot. It solves the problem of shielding generated by iron boiler and 11Mbps bandwidth made it possible for video and control stream real-time transmit within the same channel. Though TCP/IP protocol is robust, serial server is a transparent channel but cannot detect error and retransmit the data. In order to improve the reliability of serial communication, a new communication protocol is proposed. [ABSTRACT FROM AUTHOR]

Alfvén wave instabilities in a reacting tokamak plasma are calculated both analytically and numerically. Two distinct classes of eigenmodes are considered, global Alfvén eigenmodes and kinetic Alfvén waves, each driven unstable by the free energy associated with the alpha particle density gradient. The growth rates of the global Alfvén eigenmodes are given for the first time. These are basically magnetohydrodynamic (MHD) modes, whose resonances with electrons and alpha particles are calculated using kinetic theory. The calculation of kinetic Alfvén wave growth rates is improved from earlier treatments. These modes depend on electron inertia and finite ion gyroradius for their existence and have no counterpart in MHD theory. In both sets of calculations toroidal coupling of the alpha particle response to sidebands in the poloidal mode number is fully taken into account. Global modes with small parallel phase velocity are identified as the most dangerous, both because of their substantial growth rates and the expected ineffectiveness of quasilinear stabilization. The kinetic waves, on the other hand, are likely to be stabilized easily by quasilinear flattening of the alpha particle profile. Calculations using both Maxwellian and slowing-down alpha distributions are performed, showing that, for the same alpha density and energy density, the slowing-down distribution yields somewhat larger growth rates. [ABSTRACT FROM AUTHOR]

A new two-dimensional (2D) carbon crystal, different from graphene, has been prepared from 1,3,5-trihydroxybenzene, consisting of 4-carbon and 6-carbon rings in 1:1 ratio, named 4-6 carbophene by authors, in which all carbon atoms possess sp2 hybrid orbitals with some distortion, forming an extensive conjugated π-bonding planar structure. The angles between the three σ-bonds of the carbon sp2 orbitals are roughly 120°, 90°, and 150°. Each of the three non-adjacent sides of a 6C-ring is shared with a 4C-ring; and each of the two opposite sides of a 4C-ring is shared with a 6C-ring. Dodecagonal holes with a diameter of approximate 5.8 Å are regularly located throughout the 2D carbon crystal. Even though the bond energies in 4-6 carbophene are weaker than those in the graphene, the new planar crystal is quite stable in ambient conditions. The 4-6 carbophene can be synthetized from 1,3,5-trihydroxybenzene or other benzene derivatives through dehydration and polymerization reactions, and may possess several possible patterns that form a family of 2D carbon crystals. A possible side reaction involving 1,3,5-trihydroxybenzene is also discussed, which may produce a carbon-oxygen two dimensional crystal. [ABSTRACT FROM AUTHOR]