The surge of patients in the pandemic of COVID‐19 caused by the novel coronavirus SARS‐CoV‐2 may overwhelm the medical systems of many countries. Mask‐wearing and handwashing can slow the spread of ...the virus, but currently, masks are in shortage in many countries, and timely handwashing is often impossible. In this study, the efficacy of three types of masks and instant hand wiping was evaluated using the avian influenza virus to mock the coronavirus. Virus quantification was performed using real‐time reverse transcription‐polymerase chain reaction. Previous studies on mask‐wearing were reviewed. The results showed that instant hand wiping using a wet towel soaked in water containing 1.00% soap powder, 0.05% active chlorine, or 0.25% active chlorine from sodium hypochlorite removed 98.36%, 96.62%, and 99.98% of the virus from hands, respectively. N95 masks, medical masks, and homemade masks made of four‐layer kitchen paper and one‐layer cloth could block 99.98%, 97.14%, and 95.15% of the virus in aerosols. Medical mask‐wearing which was supported by many studies was opposed by other studies possibly due to erroneous judgment. With these data, we propose the approach of mask‐wearing plus instant hand hygiene (MIH) to slow the exponential spread of the virus. This MIH approach has been supported by the experiences of seven countries in fighting against COVID‐19. Collectively, a simple approach to slow the exponential spread of SARS‐CoV‐2 was proposed with the support of experiments, literature review, and control experiences.
Nitrogen is the main limiting nutrient after carbon, hydrogen and oxygen for photosynthetic process, phyto-hormonal, proteomic changes and growth-development of plants to complete its lifecycle. ...Excessive and inefficient use of N fertilizer results in enhanced crop production costs and atmospheric pollution. Atmospheric nitrogen (71%) in the molecular form is not available for the plants. For world's sustainable food production and atmospheric benefits, there is an urgent need to up-grade nitrogen use efficiency in agricultural farming system. The nitrogen use efficiency is the product of nitrogen uptake efficiency and nitrogen utilization efficiency, it varies from 30.2 to 53.2%. Nitrogen losses are too high, due to excess amount, low plant population, poor application methods etc., which can go up to 70% of total available nitrogen. These losses can be minimized up to 15-30% by adopting improved agronomic approaches such as optimal dosage of nitrogen, application of N by using canopy sensors, maintaining plant population, drip fertigation and legume based intercropping. A few transgenic studies have shown improvement in nitrogen uptake and even increase in biomass. Nitrate reductase, nitrite reductase, glutamine synthetase, glutamine oxoglutarate aminotransferase and asparagine synthetase enzyme have a great role in nitrogen metabolism. However, further studies on carbon-nitrogen metabolism and molecular changes at omic levels are required by using "whole genome sequencing technology" to improve nitrogen use efficiency. This review focus on nitrogen use efficiency that is the major concern of modern days to save economic resources without sacrificing farm yield as well as safety of global environment, i.e. greenhouse gas emissions, ammonium volatilization and nitrate leaching.
Over the past decades, higher education governance and university management have become increasingly complex worldwide in a context of unprecedented expansion and diversification. Driven by both ...external and internal pressures, higher education reforms in different nations have often been reported to follow a similar pattern: shifting from the control model to the supervisory model in nearly all aspects of their relationship with universities. While such a trend in Chinese societies has been well documented in the literature, few people have been able to identify the sticking point of higher education governance there. As a result, the concept of a doomed cycle continues to linger obstinately, viewing power delegation as leading to market disorder which, in turn, leads to tighter control. This article points out the neglect of Confucian political culture and its importance for studies of higher education governance reforms in Chinese societies. It aims to demonstrate that Western theories of and approaches to governance and autonomy in higher education cannot be simply applied to other societies of highly different historical and cultural traditions. By so doing, it attempts to shed some light on debates over governance and autonomy in higher education in a much wider context.
In this paper we report the
Fermi
Large Area Telescope (
Fermi
-LAT) detection of the
γ
-ray emission toward the young star forming region W43. Using the latest source catalog and diffuse background ...models, the extended
γ
-ray excess is detected with a significance of ~16
σ
. The
γ
-ray emission has a spectrum with a photon index of 2.3 ± 0.1. We also performed a detailed analysis of the gas content in this region by taking into account the opacity correction to the HI gas column density. The total cosmic-ray (CR) proton energy is estimated to be on the order of 10
48
erg, assuming the
γ
-rays are produced from the interaction of the accelerated protons and nuclei with the ambient gas. Comparing this region to the other star formation regions in our Galaxy, we find that the CR luminosity is better correlated with the wind power than the star formation rate (SFR). This result suggests that CRs are primarily accelerated by stellar wind in these systems.
Good advanced food traceability systems help to minimize unsafe or poor quality products in food supply chain through value-based process. From the emerging technologies forthcoming for industry ...automation, future advanced food traceability system must consider not only cyber physical system (CPS) and fog computing but also value-added business in food supply chain. Accordingly, this study presents a novel intelligent value stream-based food traceability cyber physical system approach integrated with enterprise architectures, EPCglobal and value stream mapping method by fog computing network for traceability collaborative efficiency. Furthermore, the proposed intelligent approach explores distributive and central traceable stream mechanism in assessing the most critical traceable events for tracking and tracing process. Successful case study, software system design and implementation demonstrated the performance of the proposed approach. Furthermore, experiment shows the better results obtained after the simulation execution for intelligent predictive algorithm.
•A novel intelligent value stream-based food traceability cyber physical system is created.•This paper describes a distributive and central traceable stream mechanism for traceability process.•The EA, EPCglobal and VSM methods by fog computing are used traceability efficiency.•The proposed approach aimed at optimizing complex CPS-based food traceability system in food supply chain.•This paper explores information system design architecture of intelligent CPS-based food traceability system.
Much attention have been recently paid to the upper Ordovician Wufeng shale (O3w) and lower Silurian Longmaxi shale (S1l) in the Jiaoshiba area of Sichuan Basin, which is now the largest producing ...shale gas field in China. Field emission scanning electron microscopy (FE-SEM), low pressure gas (N2 and CO2) adsorption, helium pycnometry, X-ray diffraction and geochemical analyses were performed to investigate the pore structure and fractal dimension of the pores in O3w-S1l shale formation in the Jiaoshiba area. FE-SEM images show that organic matter (OM) pores are dominant in the organic-rich samples and these pores are often irregular, bubble-like, elliptical and faveolate in shape, while in organic-poor samples, limited and isolated interparticle (interP), intraparticle (intraP) and OM pores are observed. Reversed S-shaped isotherms obtained from nitrogen adsorption are type Ⅱ, and hysteresis loops indicate that the shape of micropore in the samples is slit-or plate-like. BET surface areas and total pore volume vary from 12.2 to 27.1 m2/g and from 1.8 × 10−2 to 2.9 × 10−2 cm3/g, with an average of 19.5 m2/g and 2.3 × 10−2 cm3/g, respectively. Adsorption volume from both N2 and CO2 adsorption increases with respect to TOC contents. Porosities obtained from helium porosimetry are comparable with these from gas (CO2 and N2) adsorption in O3w-S1l shale. However, porosity determined by quantitative FE-SEM analysis is much smaller, which is mainly related to limited resolution and the small areas of investigation.
Based on the Frenkel-Halsey-Hill (FHH) model of low-pressure N2 adsorption, fractal dimensions of the pores varied from 2.737 to 2.823. Relationships between pore structure parameters and TOC content, mineral composition and fractal dimension reveal that the fractal dimension is mainly associated with micropores. Samples with higher TOC content, higher quartz content and lower clay content tend to contain more heterogeneous micropores, resulting in higher fractal dimensions and more complicated pore structure in shales. Therefore, fractal dimension is an effective parameter to reflect the complexity of pore structure and the degree of micropore development in O3w-S1l shale.
•Pore structure is characterized by a combination of FE-SEM and gas adsorption.•Fractal dimensions of nano-scale pore are calculated using fractal FHH model.•Porosities obtained from He porosimetry and gas adsorption are comparable but higher than FE-SEM.•Pore morphologies in high TOC and low TOC shales reflect pore genesis.•Controlling factors for pore structure and fractal dimensions are determined.
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•A newly acid-resistant strain JR1 was isolated from pharmaceutical wastewater.•A high nitrogen removal could be achieved by JR1 under the acidic condition.•Nitrate began to be ...utilized as substitute N-source after exhausting of ammonium.•Ammonium was utilized through assimilation along with heterotrophic nitrification.
A new acid-resistant bacterium Acinetobacter sp. JR1 was isolated, and its feasibility in nitrogen removal was investigated under acidic condition. Results show that JR1 indicated excellent ammonium and nitrate removal abilities with no accumulation of intermediates, and the maximum ammonium and nitrate removal efficiencies were 98.5% and 91.1%, respectively. Further experiments demonstrated that JR1 preferred to use ammonium with ammonium and nitrate as the mixed N-sources. For JR1, ammonium was assimilated directly as nutrients into cells and also converted into N2 through heterotrophic nitrification-aerobic denitrification. Under acidic condition, JR1 performed comparable nitrogen removal abilities to other strains under neutral or weak alkaline environment, and the efficient removal of ammonium occurred at pH 4.5–10, C/N 12–24, 20–40 °C, DO ≥4.72 mg/L, 0–1.5% of salinity, 10 mg/L Zn2+ or 20 mg/L Mn2+. All these make JR1 a promising candidate for treating acidic wastewater containing nitrogen.
Background and Aims
Hepatic macrophages can be activated by many factors such as gut‐derived bacterial components and factors released from damaged hepatocytes. Macrophage polarization toward a ...proinflammatory phenotype (M1) represents an important event in the disease progression of nonalcoholic fatty liver disease (NAFLD). However, the underlying molecular mechanisms remain incompletely understood. Exosomes have been identified as important mediators for cell–cell communication by transferring various biological components such as microRNAs (miRs), proteins, and lipids. The role of exosomes in crosstalk between hepatocytes and macrophages in disease progression of NAFLD is yet to be explored.
Approach and Results
In the present study, we reported that lipotoxic injury–induced release of hepatocyte exosomes enriched with miR‐192‐5p played a critical role in the activation of M1 macrophages and hepatic inflammation. Serum miR‐192‐5p levels in patients with NAFLD positively correlated with hepatic inflammatory activity score and disease progression. Similarly, the serum miR‐192‐5p level and the number of M1 macrophages, as well as the expression levels of the hepatic proinflammatory mediators, were correlated with disease progression in high‐fat high‐cholesterol diet–fed rat models. Lipotoxic hepatocytes released more miR‐192‐5p‐enriched exosomes than controls, which induced M1 macrophage (cluster of differentiation 11b–positive CD11b+/CD86+) activation and increase of inducible nitric oxide synthase, interleukin 6, and tumor necrosis factor alpha expression. Furthermore, hepatocyte‐derived exosomal miR‐192‐5p inhibited the protein expression of the rapamycin‐insensitive companion of mammalian target of rapamycin (Rictor), which further inhibited the phosphorylation levels of Akt and forkhead box transcription factor O1 (FoxO1) and resulted in activation of FoxO1 and subsequent induction of the inflammatory response.
Conclusions
Hepatocyte‐derived exosomal miR‐192‐5p plays a critical role in the activation of proinflammatory macrophages and disease progression of NAFLD through modulating Rictor/Akt/FoxO1 signaling. Serum exosomal miR‐192‐5p represents a potential noninvasive biomarker and therapeutic target for nonalcoholic steatohepatitis.
•Bacteria-based self-healing concrete was developed.•Bacteria induced precipitations at cracks were analyzed by SEM and XRD.•The crack self-healing effect under different conditions were studied.•The ...image characterization method was used for crack-healing quantification.
Bacteria-based self-healing concrete is a relatively new technique, therefore it is important to gather more results in simulate real conditions before applied on a bigger scale. In the present study, bacteria-based self-healing concrete was developed by adding the microbial self-healing agent which has the potential to improve self-healing capacity mainly by bacteria induced mineral precipitations. The precipitations formed at the cracks surface of the cement paste specimens were analyzed with Scanning Electron Microscope (SEM) equipped with an Energy Dispersive X-ray Spectrometer (EDS), and then examined by X-ray Diffraction (XRD). Moreover, the influence of crack width, curing ways and cracking age on the crack self-healing of cement paste with microbial self-healing agent was researched by the characterization methods of area repair rate and anti-seepage repair rate. The results showed that the microbial self-healing agent could be used to achieve the goal of concrete crack self-healing. The precipitations formed at the cracks surface were calcite, which appeared lamellar close packing morphology. However, the capacity of concrete crack self-healing depended on many factors. The crack was more and more difficult to be repaired with the increase of average crack width and the repair ability of microbial repair agent was limited for specimens with crack width up to 0.8mm. Water curing was shown to be the best way for bacteria-based self-healing concrete. In addition, the crack healing ratio of specimens dropped significantly along with the extension of cracking age. When the cracking age was more than 60days, the crack healing ratio was very small. The results above suggested that the optimal conditions were needed for the practical application of microbial self-healing agent.
English argumentative writing is difficult in second language writing for ESL students. Although there has been a lot of research on English argumentative writings, empirical research focusing on ...claims in argumentative writing is very scarce. Based on the Toulmin model, this paper studied the relationship between the claims and English argumentative writing performance. 117 time-limited writings were collected at a top university in Northeast China. The qualifiers were in the form of words, participle and sentence (QW, QP, QS), based on which claims were classified. Through the text analysis of each argumentative writing, 23 types of claims were extracted. Types of claims and 117 argumentative writings were scored respectively. Correlation analysis showed that claims based on qualifier divisions did not predict holistic writing performance. Claims in the higher-mark writings were also discussed. The findings led us to conclude corresponding pedagogy implications in promoting argumentative writings.