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Background: This study aims to analyze the changes and significance of organ function indices in patients with severe Coronavirus Disease 2019 (COVID-19) pneumonia for prediction of major organ damages and guiding treatment schemes. Methods: 63 patients with severe COVID-19 pneumonia were selected as the severe group and 73 patients with mild syndromes were selected as the mild group. SAS9.4 software was used for statistical analysis of the data. Results: Levels of ALT, AST, cTnI, Cr, PT, APTT and D-DIC of the severe group were significantly higher while PLT was lower than those of the mild group. The data of all quantitative variables were converted into categorical variables. Significantly higher levels of AST, ALB, D-DIC and higher proportion of bilateral lung involvement were observed from the severe group comparing to those in the mild group, while the difference in the other indices between the two groups was insignificant in statistical perspective. Discussion: There are significant differences in the levels of multiple organ function indices between the severe group and the mild group of patients with COVID-19 pneumonia infection. Through examining the relevant indices, conditions of patients’ multiple organ function damage could be predicted and used as guidance of treatment.

For expanding applications of spongy graphene aerogels (GAs) cost-effectively, we report a marriage of the two-step hydrothermal reduction and atmospheric drying method to fabricate a spongy CNC-graphene aerogel (CNG) with oil/water selectivity and tunable mechanical strength by a low-cost and straightforward approach. The reduced graphene oxide (rGO) with CNC by the ice-templated method can give rise to forming the hierarchical structure of hybrid GAs within the PUS network. Meanwhile, the fractured structure of PUS with a pre-compressive step arouses more versatility and durability, involving its selective and high-volume absorbability (up to 143%). The enhanced elastic modulus and more significant swelling effect than pure sponge materials give it a high potential for durable wastewater treatment.

Lignocellulosic biomass is the most abundant renewable carbon resource on earth, for which many efforts have been made to convert it using various chemocatalytic processes. Heterogeneously chemocatalytic conversion conducted based on reusable solid catalysts is the process with the greatest potential studied presently. This review provides insights into the representative achievements in the research area of heterogeneous chemical catalysis technologies for the production of value-added chemicals from lignocellulosic polysaccharides (cellulose and hemicellulose). Popular approaches for the conversion of lignocellulosic polysaccharides into chemicals, including hydrolyzation (glucose, xylose and arabinose), dehydration (5-hydroxymethylfurfuran, furfural and levulinic acid), hydrogenation/hydrogenolysis (sorbitol, mannitol, xylitol, 1,2-propylene glycol, ethlyene glycol and ethanol), selective oxidation (gluconic acid and lactic acid), have been comprehensively reviewed. However, technological barriers still exist, which have to be overcome to further integrate hydrolysis with the refinery processes based on multifunctional solid catalysts, and convert ligncellulosic polysaccharides into value-added fine chemicals. In general, the approaches and technologies are discussed and critically evaluated in terms of the possibilities and potential for further industrial implementation.

Black plastic film mulching is a common practice for potato production in the arid area of Northwest China. Many studies have reported the significant positive effect of black plastic film mulch on potato harvest, while the effect of black plastic film mulch treatment on soil nitrous oxide (N2O) emissions is still unclear. As a consequence, this study aimed to examine the effect of black plastic film mulch treatment on N2O emission from arid upland potato fields. With the static chamber-gas chromatography method, soil N2O emissions were measured. The results showed that black plastic film mulching treatment significantly increased cumulative soil N2O emissions by 21–26% compared with non-mulched treatment. Cumulative N2O emission positively correlated with soil temperature, soil moisture, soil CO2 concentration, and amoA-AOB abundance. This study indicated that black plastic film mulching, mainly through increasing soil temperature and soil moisture, increasing soil carbon dioxide (CO2) concentration, and promoting the abundance of nitrification-related functional gene of amoA-AOB, regulated N2O emissions. This study also highlighted that the specific soil environment under black plastic film mulch is conducive to N2O emissions and lay the foundation for settling the contradiction between food production and greenhouse gas mitigation in upland soils. The negative effects of black plastic film mulching on the environment should be considered in future applications in food production.

The traditional analysis method of gas content in insulating oil is gas chromatography in laboratory, which has many problems, such as long detection cycle, many manual operation links, poor repeatability and large demand for human resources. This paper introduces a kind of automatic and portable on-site detection device for gas content in insulating oil based on vacuum differential pressure method. Through modular design and using advanced technologies, for instance, vacuum degassing, vacuum sensor and high-precision independent analog-to-digital conversion, the device has multi scene applications such as on-site and laboratory detection of gas content in insulating oil. And different analysis modes such as analysis of live sampling of oil filled electrical equipment and on-line monitoring on site can be realized. The experimental results show that the detection accuracy, repeatability and reproducibility of the device meet the requirements of DL / T 423-2009. In addition, the repeatability, RSD and detection efficiency of the device are better than those of the laboratory test data due to avoiding a large number of manual operation links.

Background and aims: Calcium channel blockers (CCBs) and angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin receptor blockers (ARBs) are commonly used in the treatment of hypertension. However, it is still not clear whether there are differences among different anti-hypertensive drugs in the treatment of patients with coronavirus disease 2019 (COVID-19) and hypertension. Herein, we aimed to assess the relation between different anti-hypertensive medications and COVID-19 outcomes. Materials and methods: We conducted a retrospective analysis of 58 hypertensive patients with COVID-19 who were treated with different anti-hypertensive drugs and reviewed the clinical data obtained from electronic medical records, including epidemiological, clinical, laboratory, and the treatment and progression of the disease. Results: There was no obvious difference in clinical prognosis after using any anti-hypertensive drugs in patients with COVID-19 and hypertension, but the different anti-hypertensive drugs were associated with the use of non-invasive ventilator treatment at admission comparing two groups between ACEIs/ARBs and CCBs+ACEIs/ARBs. Conclusion: there is no evidence showing that the different use of anti-hypertensive drugs is related to outcomes of patients with COVID-19 and hypertension, even between single drug regimen and combined therapy (with at least two anti-hypertensive drugs as combined therapy).

Coronavirus disease 2019 (COVID-19) epidemic is the most widespread global pandemic in the past 100 years. Person-to-person transmission of COVID-19 infection leads to the major threat of human safety and health. At 00:00 on January 24th, 2020, Tianjin City launched the first-level response to the COVID-19 epidemic. At 18:00 on the same day, Management Committee of Dongjiang Free Trade Port Zone of Tianjin received areport that there were 15 people who had fever on the Costa Crociere carrying 4 806 people from Japan back to the home port of Tianjin Dongjiang Cruise. At the same time, there are more than 140 Chinese Hubei tourists. Tianjin Municipal Committee and Government, Tianjin Customs, Binhai New Area District Committee Government, Tianjin Health Commission, Tianjin Binhai New Area Health Commission formed an emergency command center immediately to deal with the epidemic comprehensively. At 06:40 on January 25th, 2020, the medical investigation team made up by Tianjin Binhai New Area Health Commission and Tianjin East Administration of Customs boarded the cruise ship. With reference to the customs inspection and quarantine regulations, in accordance with the Diagnosis and treatment of pneumonia caused by novel coronavirus (trial version 3) for mulated by the National Health Commission of the People's Republic of China and the Novel coronavirus infected pneumonia port control and technology plan (first version) formulated by the General Administration of Customs, combined with the actual situation of cruise ships, the medical investigation team developed the inspection standards, including door-to-door inspections, temperature measurement and epidemiological investigations on all persons on board of the cruise ship. A total of 4 806 person-times were investigated in the affected area, including 3 706 tourists and 1 100 crew members. Seventeen people at high risk of COVID-19 were identified, including three Wuhan tourists. The reports of 2019 novel coronavirus (2019-nCoV) nucleic acid detection on throat swab samples for those who were identified as high risk were returned as all negative at 14:54 on the same day. At 19:30, the medical investigation team completed the investigation and evacuated the cruise ship. The temperature measurement, medical observation and resettlement of passenger were handed over to relevant personnel. After 2 weeks, the follow-up result of 2019-nCoV nucleic acid of 17 high risk people were all negative. The overall command and comprehensive coordination of the onshore command center together with the rigid principles and excellent responds ability of the on-site epidemic investigation team ensured the successful completion of the epidemic investigation work, and also provided reference for further improving the management and disposal capacity of public health emergencies at sea.

Background: This study aims to analyze the changes and significance of organ function indices in patients with severe Coronavirus Disease 2019 (COVID-19) pneumonia for prediction of major organ damages and guiding treatment schemes. Methods: 63 patients with severe COVID-19 pneumonia were selected as the severe group and 73 patients with mild syndromes were selected as the mild group. SAS9.4 software was used for statistical analysis of the data. Results: Levels of ALT, AST, cTnI, Cr, PT, APTT and D-DIC of the severe group were significantly higher while PLT was lower than those of the mild group. The data of all quantitative variables were converted into categorical variables. Significantly higher levels of AST, ALB, D-DIC and higher proportion of bilateral lung involvement were observed from the severe group comparing to those in the mild group, while the difference in the other indices between the two groups was insignificant in statistical perspective. Conclusions: There are significant differences in the levels of multiple organ function indices between the severe group and the mild group of patients with COVID-19 pneumonia infection. Through examining the relevant indices, conditions of patients’ multiple organ function damage could be predicted and used as guidance of treatment.

Background: This study aims to analyze the changes and significance of organ function indices in patients with severe Coronavirus Disease 2019 (COVID-19) pneumonia for prediction of major organ damages and guiding treatment schemes.Methods: 63 patients with severe COVID-19 pneumonia were selected as the severe group and 73 patients with mild syndromes were selected as the mild group. SAS9.4 software was used for statistical analysis of the data.Results: Levels of ALT, AST, cTnI, Cr, PT, APTT and D-DIC of the severe group were significantly higher while PLT was lower than those of the mild group. The data of all quantitative variables were converted into categorical variables. Significantly higher levels of AST, ALB, D-DIC and higher proportion of bilateral lung involvement were observed from the severe group comparing to those in the mild group, while the difference in the other indices between the two groups was insignificant in statistical perspective.Discussion: There are significant differences in the levels of multiple organ function indices between the severe group and the mild group of patients with COVID-19 pneumonia infection. Through examining the relevant indices, conditions of patients’ multiple organ function damage could be predicted and used as guidance of treatment.

This study is aimed at identifying potential molecular mechanisms and candidate biomarkers in the left atrial regions for the diagnosis and treatment of valvular atrial fibrillation (VAF). Multibioinformatics methods, including linear models for microarray analysis (LIMMA), an SVA algorithm, CIBERSORT immune infiltration, and DNA methylation analysis, were employed. In addition, the protein-protein interaction (PPI) network, Gene Ontology (GO), and molecular pathways of differentially expressed genes (DEGs) or differential methylation regions were constructed. In all, compared with the normal rhythm group, 243 different mRNAs (29 downregulated and 214 upregulated) and 26 different lncRNAs (3 downregulated and 23 upregulated) were detected in the left atrium (LA) of atrial fibrillation (AF) patients, and the neutrophil and CD8+ T cell were infiltrated. Additionally, 199 different methylation sites (107 downregulated and 92 upregulated) were also identified based on DNA methylation analysis. After integration, ELOVL2, CCR2, and WEE1 were detected for differentially methylated and differentially transcribed genes. Among them, WEE1 was also a core gene identified by the competing endogenous RNA (ceRNA) network that included WEE1-KRBOX1-AS1-hsa-miR-17-5p, in VAF left atrial tissue. We combined the DNA methylation and transcriptional expression differential analysis and found that WEE1 (cg13365543) may well be a candidate gene regulated by DNA methylation modification. Moreover, KRBOX1-AS1 and WEE1 can compete endogenously and may mediate myocardial tissue infiltration into CD8+ T cells and participate in the AF process.

A field experiment was conducted to investigate the combined application effects of fly ash (FA) (0, 5%, 10%, and 15% (w/w) soil) and polyacrylamide (PAM) (0, 0.006% and 0.012% (w/w) soil) on the edge of Hobq Desert in Inner Mongolia, China from May 2016 to October 2018. Seven different ratios of FA and PAM were selected as evaluation objects, a total of 14 soil property indices and 9 Artemisia ordosica growth indices were selected as evaluation indicators, and the entropy weight method was employed to evaluate the soil physicochemical properties and vegetation growth performances under FA and PAM amendments. The results showed that the F15P1 (15% FA + 0.006% PAM) and F5P1 (5% FA + 0.006% PAM) were the effective treatments for soil improvement and Artemisia ordosica growth respectively. Considering the soil properties and Artemisia ordosica growth in 2016&ndash, 2018 synthetically, the highest score was observed in the F5P1, followed by the F5P2 (5% FA + 0.012% PAM) and F10P1 (10% FA + 0.006% PAM) treatments. The optimal amounts for FA and PAM should be recommended as 5% and 0.006%, respectively.

Ocean wave energy is one of the most promising clean and renewable energy, triboelectric nanogenerators (TENGs) can be seen as a promising technology by harvesting blue energy to reduce greenhouse gas emissions. This work utilized a novel process to fabricate porous foam-shaped PDMS vibrator combined with aluminium metal electrode film and polyimide (Kapton) film to form a contact separation single electrode vibrating friction nanogenerator. The vibratory TENG with porous PDMS spherule (P-TENG) as vibrator enhanced the output performance with facile manufacturing process. The results show that the output voltage of the vibratory friction nanogenerator with porous spherules as the vibratory friction nanogenerator is 38.89% higher than that with solid ones and the charge accumulation and release period is eight times higher. Given the features of exceptional output performance, unprecedented robustness and universal applicability resulting from porous structure, the P-TENG is promising candidate for ocean wave energy harvesting in our water-wave experiment.

In the present work, a new phenomenal model is proposed for modeling and simulating tearing mechanical properties on an airship envelope fabric. The greatest advantage of the phenomenal model is that such model is capable of calculating the tearing strength of a plain weave fabric by simply uniaxial tearing tests rather than the expensive and complex pressurized cylinder tests. The geometric progression technique is employed to calculate the stress distribution on the crack tip. The stress transfer coefficient Q is derived to be 0.9656. Three types of SEN (single-edge-notched) specimens were researched by the uniaxial tearing tensile tests. The effects of specimen width and the crack length ratio on the tearing strength of the airship envelope fabric are studied thoroughly. A good agreement between such model and experimental data is obtained, and the deviation is lower than 5%. Meanwhile, compared with the new phenomenal model and the Thiele’s formula, this new phenomenal model is verified to be more accurate while calculating the tearing strength of a plain weaving airship envelope fabric in the uniaxial tearing tensile load.

In order to study the influence of haze weather on audible noise of HVDC transmission line, a calculation model of ion flow field of HVDC transmission line considering the influence of haze is established, and then the relationship between different haze levels, different haze particle concentrations and audible noise is analyzed by taking the maximum potential gradient on the conductor surface as the intermediary. Then a ± 800kV DC transmission line is simulated and the results show that the audible noise will be more prominent with the increase of haze concentration, and the increment is more obvious at higher haze concentration; The charging of haze particles is the principal origin for the increase of audible noise, and the effect of PM2.5 is the most significant.

This paper reports the central tearing properties of a new airship envelope fabric, GQ-6, from experimental investigation and theoretical analysis. First, the effects of the load ratio, the initial crack length, and the crack orientation on the tearing mechanical properties of such material were evaluated. The experimental results revealed that the mechanical properties of GQ-6 decrease with the increase of initial crack length. Two fracture modes were observed, e.g. either along the warp or the weft yarns directions, which depend on crack orientation and load ratio. Oriented crack can be represented by non-oriented crack with crack equivalent length under biaxial condition. The toughness KICfor the fabric was determined based on experimental results, as well as critical energy release rate GIC. A comparison of the mechanical behaviors of this textile under uniaxial and biaxial tensile condition is also presented. The allowable crack length for GQ-6 envelope fabric during working condition is estimated.

This paper investigated the mechanical properties of GQ-6 subjected to a tremendous amount of uniaxial tests. Such material is a new kind of ultra high molecular weight polyethylene fiber and aimed to be adopted in stratospheric airship. To begin with, mono-uniaxial tensile tests were conducted. The cycling-uniaxial tensile experiments were then carried out on the basis of the mono-uniaxial tensile tests data. Finally, performances of welding seams were thoroughly investigated with forty welding specimens. Results of mono-uniaxial tensile tests revealed that such woven fabric possesses high tensile strength and low elongation ratio at break. Meanwhile, the stress–strain behaviors were fitted by the Ogden model and a good agreement between such model and experimental data was obtained. Influences of the uniaxial loading cycle on such woven stiffness were discussed and the elastic moduli were defined with a standard hysteresis loop. For the welding tests, four types of overlapping welding failures were discovered. Compared with intact specimens, an appropriate welding width of 60 mm and an approximate 15% discount of the ultimate tensile stress on the intact textile were obtained.

A series of perylene-diimide-based small molecules have been designed to explore their optical, electronic and charge transport properties as organic solar cell materials. The frontier molecular orbitals analysis has turned out that the vertical electronic transitions of absorption are characterised as intramolecular charge transfer between perylene diimide moieties and substituent aromatic groups. Our results suggest that the optical and electronic properties and reorganisation energies are affected by the introduction of different aromatic groups to these molecules. The calculation results showed that the designed molecules own the large longest wavelength of absorption spectrum, the oscillator strength and absorption region values. On the basis of the investigated results, the designed molecules could be used as solar cell material with intense broad absorption spectra. Furthermore, they are expected to be the promising candidates for hole and/or electron transport materials.

This article proposed a new convenient method to obtain tear strength of an airship envelope fabric, which is a laminated plain weave fabric with the ultra-high molecular weight polyethylene fibers. First, a modified formula based on Maekawa’s empirical formula was derived. Uniaxial tear tests were then conducted on three series of single-edge notched specimens with varying widths and their critical tear stresses were measured. The experimental result showed that critical tear stress decreases with the reduction of specimen width when initial crack length is fixed. Afterward, the tear stresses of the fabric were simulated by Maekawa’s empirical formula, the modified formula, and Thiele formula. By comparing the theoretical results with the experimental results, the modified formula was verified to be consistent well with the test data. Finally, an equation was derived, which shows tear strength of this fabric decreases as initial crack length increases. For instance, when the initial crack length is 31.75 mm, the tear strength is only 44.52% of the tensile strength.

Samarium methoxide incorporating the ene-diamido ligand L(DME)Sm(μ-OMe)2Sm(DME)L (1; L = [DipNC(Me)C(Me)NDip](2-), Dip = 2,6-iPr2C6H3, and DME = 1,2-dimethoxyethane) has been prepared and structurally characterized. Complex 1 catalyzed the syndiospecific polymerization of styrene upon activation with phenylsilane and regioselective hydrosilylation of styrenes and nonactivated terminal alkenes. Unprecedented regioselectivity (99.0%) for both types of alkenes has been achieved with the formation of Markovnikov and anti-Markovnikov products in high yields, respectively, whereas the polymerization of styrene resulted in the formation of syndiotactic silyl-capped oligostyrenes. The kinetic experiments and density functional theory calculations strongly support a samarium hydride intermediate generated by σ-bond metathesis of the Sm-OMe bond in 1 with PhSiH3. In addition, the observed regioselectvity for hydrosilylation and polymerization is consistent with the calculated energy profiles, which suggests that the bulky ene-diamido ligand and samarium hydride intermediate have important roles for regio- and stereoselectivity.

Drip irrigation has been shown to be an effective method for achieving high potato yields. Soil matric potential (SMP) and irrigation frequencies are two important factors in optimizing potato production and tuber quality. This chapter reviews and discusses a case study of potato evapotranspiration (ET) and productivity in drip irrigated potato systems in the North China Plain in 2001 and 2002, as affected by SMP and irrigation frequency. The experiment in this case study included five treatments for SMP: F1 (−15 kPa), F2 (−25 kPa), F3 (−35 kPa), F4 (−45 kPa) and F5 (−55 kPa) and six treatments for irrigation frequency: N1 (daily irrigation), N2 (2 day intervals), N3 (3 day intervals), N4 (4 day intervals), N6 (6 day intervals) and N8 (8 day intervals). In general, ET was reduced at lower SMP, as F5 had the lowest ET (150 mm) among the five treatments, and F2 had the highest (208 mm). F1 experienced somewhat waterlogged conditions. Potato ET losses declined as SMP dropped from −25 to −55 kPa. Higher frequency of irrigation enhanced both potato tuber growth and water use efficiency (WUE). Reducing irrigation frequency from N1 to N8 resulted in significant yield reductions by 33.4% and 29.1% in the 2001 and 2002 growing seasons, respectively. Based on the results, the authors of this case study suggested a SMP threshold of −25 kPa, and an irrigation frequency of once a day for the as a target for drip irrigation management for potato production in the North China Plain.

Northern China is a major potato production region, and water-saving measures that can enhance both potato yield and quality play an important role in this region due to general water shortages. Plastic mulch has been used as an effective water-saving measure for potato cultivation in China. This chapter reviews the case studies on the effects of plastic mulching on potato growth, conducted at two areas of North China. Data from these experiments indicated that plastic mulching could save irrigation water and reduce evapotranspiration in most cases. Daily mean soil temperature under mulch was 2–9°C higher than that without mulch, especially during the early growth stage. However, as the plant canopy enlarged, the soil temperature difference between mulched and non-mulched plots became smaller. Plastic mulch could restrain or enhance potato plant growth during the early growth, dependent on the microenviromental air and soil temperatures. The possible negative effects of plastic mulching included a lower emergence, lower potato tuber yield, and poorer tubers quality, which may be attributable to the poorer soil aeration and detrimentally high soil temperature associated with plastic mulch when the air temperature is high. As mulch duration is an influential factor, data from these case studies suggested that 60 days of mulching duration was most favorable for potato production in the tested areas. Mulch removal after 60 days was proposed to avoid subsequent negative effects. To complement the current knowledge on the plastic mulching research, future research should be focused on the hydrothermal dynamics and its effect on potato growth with different drip irrigation regimes under plastic mulching conditions.