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To study the effect of different drying methods on volatile components of jasmine tea, headspace solid phase microextraction combined with gas chromatography-mass spectrometry and electronic nose technology were used for quantitative and qualitative analysis of the volatile compounds in jasmine tea dried by four methods, including heat pump drying, hot air drying, microwave drying and vacuum-freeze drying. The results showed that, the top three response values of electronic nose sensors were W1W, W2W and W5S. Under different drying treatments, it can better reflect the differences in volatile substances in jasmine tea. The results of HS-SPME-GC-MS showed that a total of 96 volatile components (alcohol esters, aldehydes, ketones, olefins and other classes) were identified in jasmine tea by four different drying methods. Among these components, the species of olefin compounds were the most with the amount of 37. The total amounts of the volatile components in jasmine tea by freeze-drying were the most abundant with a relative content of 47.382 μg/g, followed by heat pump drying with a relative content of 44.429 μg/g. And the relative contents of olefin and alcohols were higher than other components. The JTF (jasmine tea fragrance) index of jasmine tea was the highest with a amount of 4.766 by heat pump drying. Therefore, HS-SPME-GC-MS combined with electronic nose technology could be used to distinguish the quality of jasmine tea by different drying methods, and would provide theoretical reference for the selection of drying methods in jasmine tea production.

Summarizes Weissiella spp. including the isolation and identification, biological properties, acid tolerance, bacterial inhibition, extracellular polysaccharide production, probiotic properties, histological studies, and food and pharmaceutical applications, and provides suggestions for the development and utilization of Weissiella spp.

There are many unmeasurable branches along with distribution lines. The sensitivity and speed of traditional three-stage overcurrent protection lacks when applied to these lines. Even the phasor differential protection cannot identify internal faults sensitively to maintain sufficient safety under external faults. With 5G communication is penetrating the field of power grid automation, a comprehensive protection scheme for branched distribution lines is proposed. Firstly, analyze negative sequence currents phase characteristics under internal or external faults, and negative-sequence current phase-comparison protection is proposed. Secondly, in some harsh working conditions, 5G communication's synchronization cannot be guaranteed, or even out of step. A positive sequence amplitude differential protection is introduced. Finally, the three-stage overcurrent protection is combined to form a complete set of protection coordination schemes when communication interruption or some extreme situations. A 10 kV active distribution network model is built in PSCAD/EMTDC to verify the proposed protection criteria and scheme. The simulation results demonstrate the effectiveness of the proposed protection criteria and scheme.

The COVID-19 pandemic led to significant burnout among nurses, resulting in a shortage of nursing staff. Issues related to nursing work have received significant attention recently, and only healthy nurses are capable of providing good quality patient care. The authors employed Bronfenbrenner's Ecological System Theory to analyze the impact of the COVID-19 pandemic on nurses and proposed specific strategies and recommendations to enhance the nursing workplace. Under the Ecological System Theory, several factors, including inadequate preparedness, dangerous working environment, work-family conflicts, discrimination due to public panic, and health damage, contribute to nurse burnout. Whether during or after the COVID-19 pandemic, it is necessary to provide education programs to enhance the professional abilities of nurses, foster policies that promote a positive practice work environment, implement a triage system based on the severity of patients, elevate the image of the nursing profession, monitor the health of nurses, and advocate for transformational leadership. The nursing workplace should help nurses gain greater confidence and improve their ability to handle various workplace challenges. In the future, medical institutions should provide a better work environment for nurses and expect the public to pay more attention to the development of the nursing profession. [ABSTRACT FROM AUTHOR]

The objective of this study is to clarify relay intercropping crop growth characteristics and its effects on yield formation under nitrogen application and interspecific distance. In this study, the soybean/maize strip relay intercropping system was used as the main body, to explore the crop growth rate, dry mater accumulation, and distribution, and yield differences under different nitrogen levels (nitrogen application and no nitrogen application) and interspecific distance (the spacing of soybean 30, 45, 60, 75, and 100 cm mono-cropping), to fit the process of crop dry mater accumulation, and comprehensively analyze the crop growth law and yield benefit. The results showed that the maximum growth rate of maize was reached from male stage to milking stage, and the maximum growth rate was 30 cm (MS30) without nitrogen application, which was 34.99% higher than that of monoculture maize (MM100). The growth rate of relay intercropping was significantly lower than that of monoculture soybean (SS100) before the first flowering stage, but higher than that of SS100 after the first flowering stage, with the highest spacing of 60 cm (MS60), and 78.91% higher than that of SS100 from full flowering stage to full pod stage without nitrogen application. The logistic equation could fit well the matter accumulation process of maize and soybean, and the R2 were all above 0.95. Compared with no nitrogen application, nitrogen application delayed the accumulation peak and increased the biomass of maize. The matter accumulation of intercropping soybean was slower than monoculture at the early growth stage, but MS45 and MS60 were gradually equal to or even exceeded monoculture soybean at later growth stage. Nitrogen application increased the dry matter allocation rate to the grain, and maize yield increased by 10.05% and 40.90% in two years, respectively. With the increase of interspecific distance, soybean yield increased first and then decreased, with the highest value in MS60 and the lowest value in MS30. In the two years, soybean yield in MS60 was 23.88% and 31.77% higher than MS30 under no nitrogen application and nitrogen application, respectively. The land equivalent ratio under relay intercropping was all above 1.35, among which MS60 under nitrogen application was the largest (1.89). The suitable interspecific distance (interspecific distance 60 cm) under relay intercropping can realize the cooperative growth of maize and soybean, increase crop growth rate, promote the accumulation and distribution of matter, and improve the system yield and land equivalent ratio. [ABSTRACT FROM AUTHOR]

Reasonable field configuration can improve crop growth environment and increase system yield in intercropping systems. To further improve the field configuration technology for high yield and efficiency in the soybean-maize strip intercropping system in Southwest China, the soybean-maize strip intercropping system was used as the research object, and two factor split zone design was adopted. The effects of two bandwidths of 2.0 m (B1) and 2.4 m (B2) and four plant spacings of 9 cm (P1), 11 cm (P2), 14 cm (P3), and 18 cm (P4) on soybean biomass accumulation, allocation, grain filling, and yield were comprehensively analyzed. The results showed that the net photosynthetic rate of each plant spacing treatment under B2 bandwidth was higher than that of B1, and the two--year average increased by 14.26% compared with B1 under B2. At the same bandwidth, the net photosynthetic rate reached the maximum in B1P4 and B2P4, which increased by 13.57% and 25.21% compared with B1P1 and B2P1 at flowering stage, respectively. The biomass accumulation of soybean population increased and then decreased with the increase of plant spacing under the two bandwidths, and reached the maximum at B1P3 and B2P2, respectively, and B2 increased by 9.82%--22.08% compared with B1 at maturity stage. And the increase of bandwidth and plant spacing promoted the accumulation and transfer of soybean post-flowering matter to grain. Compared with B1, post-flowering dry matter accumulation and dry matter transfer increased by 13.82--28.01% and 13.38%--37.76% under B2 treatment, respectively, and the proportion of grain matter accumulation increased to 41.80%--44.26%. The increase of biomass accumulation improved the grain filling process, and the active grain-filling period (D) of soybean under B2 was extended by 2--3 days compared with B1. The mean grain-filling rate reached its maximum at P4 and increased by 5.80% and 6.58% compared with P1 under the two bandwidths. The yield results showed that, with the increase of bandwidth and plant spacing, the effective plants decreased, and the seeds per plan and 100-seed weight increased in the soybean-maize strip intercropping model. The soybean yield under B2 bandwidth increased by 22.32%--36.87% compared with B1, it reached the maximum in B1P3 and B2P2 under the two bandwidths, respectively, and increased by 17.83%--26.44% and 10.71%--10.76% compared with B1P1 and B2P1 for two years. In summary, the soybean plant spacing of 11 cm at the bandwidth of 2.4 m can effectively improve the post-flowering dry matter accumulation and allocation, promote grain filling, increase the number of seeds per plant and 100-seed weight, improve soybean population yield, and achieve the high yield and high efficiency in the soybean-maize intercropping system. [ABSTRACT FROM AUTHOR]

Optimal allocation of water resources can solve the problems of regional water resources shortage and unreasonable utilization, and in recent years optimization algorithms have become an important tool for obtaining the results of optimal allocation of water resources. To effectively alleviate the problems of slow convergence, local optimization and prematureness in existing optimal allocation algorithms, this paper introduces a new metaheuristic algorithm: the Cheetah Optimizer (CO), with the advantages of fast convergence, robustness, and superiority-seeking ability, which is applied to the optimal allocation of water resources. Taking Taiyuan as the study area, this paper establishes a water resource optimization model with the objectives of economic, social, and ecological benefits, and CO is used to solve the model, then compares and analyzes the results with the Genetic Algorithm (GA). The results show that the total pollutant discharge of CO is within the control target of the planning year (2030), the regional satisfaction reaches 0.98, which can meet the demand for basic and development water; compared with the current year (2020), the proportion of domestic water consumption decreases by 22.58%, and the proportion of water consumption in production increases by 10.53%, 25.81% and 12.5%, respectively. The water supply ratio of surface water and groundwater is reduced by 21.70% and 11.14%, respectively, the water supply ratio of reuse water and yellow diversion water is increased by 5.43% and 27.40%. It accords with the idea of water resources allocation in Taiyuan, and verifies the effectiveness of CO. Compared with GA, CO has increased regional satisfaction, integrated water value and water distribution equity by 7.10%, 3.57% and 56.52%, respectively, reduced pollutant emissions and water shortage by 3.11% and 3.85%, at the same time, it has better coordination, which verifies the superiority of the CO. The results show that CO is reasonable and feasible to solve the optimal allocation model of water resources, which can provide a new method for solving the optimal allocation model of water resources. [ABSTRACT FROM AUTHOR]

Objective To explore the molecular characteristics of Staphylococcus aureus (S. aureus) in children, and to compare the molecular characteristics of different types of strains (infection and colonization strains) so as to reveal pathogenic molecular markers of S. aureus. Methods A cross-sectional study design was used to conduct nasopharyngeal swab sampling from healthy children in the community and clinical samples from infected children in the hospital. Whole genome sequencing was used to detect antibiotic resistance genes and virulence genes. A random forest method to used to screen pathogenic markers. Results A total of 512 S. aureus strains were detected, including 272 infection strains and 240 colonization strains. For virulence genes, the carrying rates of enterotoxin genes (seb and sep), extracellular enzyme coding genes (splA, splB, splE and edinC), leukocytotoxin genes (lukD, lukE, lukF-PV and lukS-PV) and epidermal exfoliating genes (eta and etb) in infection strains were higher than those in colonization strains. But the carrying rates of enterotoxin genes (sec, sec3, seg, seh, sei, sel, sem, sen, seo and seu) were lower in infection strains than in colonization strains (P<0.05). For antibiotic resistance genes, the carrying rates of lnuA, lnuG, aadD, tetK and dfrG were significantly higher in infection strains than in colonization strains (P<0.05). The accuracy of cross- validation of the random forest model for screening pathogenic markers of S. aureus before and after screening was 69% and 68%, respectively, and the area under the curve was 0.75 and 0.70, respectively. The random forest model finally screened out 16 pathogenic markers (sem, etb, splE, sep, ser, mecA, InuA, sea, blaZ, cat(pC233), blaTEm-1A, aph(3')-III, ermB, ermA, ant(9)-Ia and ant(6)-Ia). The top five variables in the variable importance ranking wcrc sem (OR=0.40), etb (OR=3.95), splE (OR=1.68), sep (OR=3.97), and ser (OR=1.68). Conclusions The random forest model can screen out pathogenic markers of S. aureus and exhibits a superior predictive performance, providing genetic evidence for tracing highly pathogenic S. aureus and conducting precise targeted interventions. [ABSTRACT FROM AUTHOR]

Objective To investigate the difference in the therapeutic effect of mycophenolate mofetil (MMF) or cyclophosphamide (CTX) in children with Henoch-Schönlein purpura nephritis (HSPN) of different age groups. Methods A retrospective analysis was conducted on the clinical data of 135 children with HSPN who were treated with MMF or CTX in the Department of Nephrology, Children's Hospital Affiliated to Capital Institute of Pediatrics, from October 2018 to October 2020. According to the immunosuppressant used, they were divided into two groups: MMF group and CTX group, and according to the age, each group was further divided into two subgroups: ≤ 12 years and >12 years, producing four groups, i.e, the ≤ 12 years MMF subgroup (n=30), the >12 years MMF subgroup (n=15), the ≤ 12 years CTX subgroup (n=71), and the >12 years CTX subgroup (n=19). All children were followed up for at least 12 months, and the above groups were compared in terms of clinical outcomes and the incidence rate of adverse reactions. Results There was no significant difference in the complete response rate between the MMF group and the CTX group after 3, 6, and 12 months of treatment (P>0.05). There were no significant difference in the complete response rate and the incidence rate of adverse reactions between the >12 years MMF subgroup and the í 12 years MMF subgroup at 3, 6, and 12 months of treatment (P>0.05). The >12 years CTX subgroup had a significantly lower complete response rate than the ≤ 12 years CTX subgroup at 6 and 12 months of treatment (P<0.05). The >12 years CTX subgroup had a significantly higher incidence rate of adverse reactions than the >12 years MMF subgroup (P<0.05). Conclusions The efficacy and adverse reactions of MMF arc not associated with age, but the efficacy of CTX is affected by age, with a higher incidence rate of adverse reactions. CTX should be selected with caution for children with HSPN aged >12 years. [ABSTRACT FROM AUTHOR]

The selection of shade-tolerant and high-light-efficient soybean varieties is one of the important research elements of the maize-soybean ribbon complex cropping model. By analyzing the differences in leaf morphology and photosynthetic physiological responses between wild and cultivated soybean seedlings under normal and shaded conditions, we can reveal their shade-tolerance mechanisms and response differences, which can provide a theoretical basis for the breeding of new shade-tolerant and high-light-efficient soybean varieties. In this study, two types of cultivated soybean (Nandou 12 and Tianlong No.1) and two types of wild soybean (W1 and W2) were used as experimental materials to investigate their response to shade under two light environments: natural light and 50% shade. The results showed that the specific leaf weight, leaf thickness, fenestrated tissue thickness, net photo-synthetic rate, stomatal conductance, and photosynthetic pigment content of wild and cultivated soybean were significantly lower under shade stress than under natural light. In shade, cultivated soybean showed higher variation in net photosynthetic rate, photosynthetic pigment content, spongy tissue thickness, and leaf area than wild soybean, while specific leaf weight and ratio of fenestrated tissue to spongy tissue were significantly lower than wild soybean. Wild soybean can improve its adaptation to low light conditions by maintaining Chlb content, increasing the proportion of chlorophyll in photosynthetic pigments and stimulating potential maximum photosynthetic activity as a response. The differences in the response of wild and cultivated soybean to shade conditions could provide theoretical support for future breeding of shade-tolerant soybean. [ABSTRACT FROM AUTHOR]

Objective To express recombinant Burkholderia pseudomallei (B. pseudomallei) type Ⅲ secretion system BipD protein, prepare its polyclonal antibodies and verify their immunological traits. Methods The recombinant pET-28a-BipD plasmid was generated, and the pET-28a-BipD-carried E.coli BL21 (DE3) bacteria were induced with isopropyl-β-d-thiogalactoside (IPTG) to express recombinant BipD (rBipD) protein. The rBipD was obtained by affinity chromatography using His Trap column, then mixed with Fredrick's adjuvant to immunize BALB/c mice by intraperitoneal injection in order to obtain anti-rBipD polyclonal antibodies. The immunoreactivity of rBipD was detected by Western blot assay using rabbit anti-melioidosis serum and the serum from melioidosis patients. The immunogenicity of rBipD was evaluated using Western blotting and immunofluorescence staining. Finally, rBipD was used to establish an indirect ELISA to detect serum antibodies of clinical melioidosis patients. Results The recombinant plasmid pET-28a-BipD was successfully constructed and transformed into E.coli BL21 (DE3) to induce rBipD expression with IPTG treatment. The obtained rBipD had a relative molecular weight of 36×103 and a purity of 95.4%, and had good immunogenicity and immunoreactivity. It could induce the production of specific antibodies after immunizing mice, and mouse polyclonal antibodies against rBipD were prepared with the titer of 1∶512 000. rBipD of 5.0 μg/mL produced specific immune response with the serum of melioidosis patients, but had no specific reaction with the serum of tuberculosis patients, with statistical difference (P < 0.01). Conclusion rBipD with immunological activity is successfully prepared and purified, and its polyclonal antibodies are also developed, which provide a good tool for clinical immunological diagnosis and study of immune mechanism of B. pseudomallei infection.

Metal oxides are often used as electrode materials for supercapacitors because of their high capacity， low cost， suitability for commercialization， and environmental friendliness. In this study， Mn-MOF was used as a precursor and placed in ethanol for ion exchange and etching reaction with Co（NO3）2， followed by heat treatment in air， and finally highly crystalline CoMn2O4 two-dimensional nanorod structures were obtained on a carbon cloth（CC） substrate. SEM and XRD analyses of CoMn2O4/CC prepared with different Co（NO3）2 additions and Mn2O3/CC obtained by direct heat treatment were performed， and electrochemical properties were measured by cyclic voltammetry test， constant current charge/discharge test and AC impedance test. The results show that the parent structure of CoMn2O4/CC is relatively well preserved after 0.3 g Co（NO3）2 etching， forming a nano-hollow structure， and the vertical nanorod structures grow in situ on carbon cloth after heat treatment wrapping carbon fibers uniformly and densely， ensuring high mechanical stability and electrical conductivity due to the absence of any binder addition. The electrode material has an area specific capacitance of 809.8 mF·cm-2 at the current density of 1.2 mA·cm-2 and the capacitance retention is 79.1% after 5000 cycles at the current density of 5 mA·cm-2，showing potential application prospects.

In order to study the corrosion resistance of three different superhydrophobic coatings (MZS-1, MZS-2 and ZnO@ZIF-8) on AZ91D magnesium alloy surface in 5% (mass fraction) NaCl solution. The microstructure, wettability and corrosion resistance of the superhydrophobic composite coating were tested and characterized by field emission scanning electron microscope, static contact angle tester, electrochemical workstation and salt spray tester, respectively. The results show that the corrosion of the superhydrophobic coatings does not occur until 192 h after salt spray treatment among the three types of superhydrophobic coatings, and the corrosion of the MZS-1 superhydrophobic coating is the most serious. The surface pitting of the MZS-2 superhydrophobic coating doesn't occur until 240 h later, and the contact angle is still high after salt spray treatment, so the corrosion resistance of the MZS-2 composite coating is the best.The polarization curve tests indicate that the corrosion current density of three superhydrophobic coatings are still one order of magnitude lower than that of the metal matrix after salt spray treatment for 240 h, showing excellent corrosion resistance. The superhydrophobic coating can effectively increase the corrosion resistance of metal materials.It can effectively prevent the infiltration of corrosive ions and provide long-term protection for the matrix because of its water repellency.

To exploit the difference of root nodule growth and nitrogen fixation potential of soybean in maize-soybean relay strip intercropping system, a two-year filed experiment with different nodulation characteristics soybean varieties (Gongxuan 1, Guixia 3, and Nandou 25) under different maize-soybean spacing (30, 45, 60, and 75 cm) was conducted. The results showed that the peaks of soybean nodule number and fresh weight were delayed under the intercropping system compared with soybean monoculture. The root nodule number and fresh weight of each variety under 60 cm were significantly higher than those of other spacing treatments, and were higher than those of monoculture soybean after reaching the peak stage. The differences among varieties were as follows: Nandou 25 > Guixia 3 > Gongxuan 1. Compared with soybean monoculture, nitrogen fixation potential of soybean nodules per plant before the beginning seed stage (R5) under intercropping mode was reduced. However, nitrogen fixation potential per plant of Gongxuan 1, Guixia 3, and Nandou 25 increased by 8.53%, 16.40%, and 13.70% on average in two years under 60 cm at R5 stage. The accumulation process of inclusions in infected cells of different soybean varieties was quite different. Compared with soybean monoculture, the number of bacteroids increased under 60 cm at R5, among which poly-P-hydroxybutyrate (PHB) increased, and Nandou 25 was the best. Therefore, to improve the number of soybean nodule bacteroids, PHB and nitrogen fixation potential the appropriate inter-plant row spacing (60 cm) under intercropping can increase soybean nodule number and fresh weight at R5 stage, and Nandou 25 with strong nodulation had the best effect. [ABSTRACT FROM AUTHOR]

Objective: This study focused on investigating the enzymatic characteristics of D-lactate dehydrogenase (D-LDH) in Leuconostoc citreum KM20. Methods: The D-lactate dehydrogenase gene (LDH) from L.citreum KM20 was cloned and expressed to construct expression plasmid, and then transformed into Escherichia coli BL21 (DE3) for overexpression. Results: The enzymes encoded by LCK_00027 and LCK_00222 were purified by Ni-NTA column affinity chromatography with molecular mass of 40.0 kDa and 38.5 kDa, respectively. The specific activities were 2.18 U/mg and 153.10 U/mg, respectively. The optimal pH and temperature for pyruvate reduction were 8.0 and 40 ℃, respectively, while for the LCK_00222 encoding enzyme lactic acid oxidation the values were 12.0 and 30 ℃, respectively. The two enzymes had high activities toward oxaloacetic acid, sodium phenylpyruvate, and 2-oxoglutaric acid. Ca2+, Cu2+, and Na+ promoted the activity of the two enzymes, whereas Zn2+ and SDS inhibited. In addition, the Kcat/Km of LCK_00027 and LCK_00222 to pyruvate were 6.04×102 L/(mol·s) and 2.28×104 L/(mol·s), respectively. The Kcat/Km of LCK_00222 encoding enzyme to D-lactic acid was 65.0 L/(mol·s). Conclusion: D-LDH-1 and D-LDH-2 are key enzymes catalyzing the synthesis of D-lactic acid in Leuconostoc citrate.

[Objective] To study the physiological response of sunflowers to broomrape parasitism and the related metabolic pathways, as well as understanding the molecular mechanism of sunflower resistance to broomrape parasitism. [Methods] The broomrape-resisant (s41) and -sensitive (s26) sunflowers were used as the testing materials. Transcriptome analysis of 4 samples under the condition of parasitic stress was carried out, and physiological verification analysis of key metabolites was carried out. [Results] (1) Under inoculation, the plant height and root number of susceptible materials were affected significantly, and some of them were even unearthed, while the resistant materials had no obvious changes, and only a few were parasitized. (2) The number of DEGs was 6 362, 6 609, 5 490 and 5 469 by screening the differential genes among the samples. GO analysis showed that the four comparison groups, namely s26-s41, s26CK-s41CK, s26-s26CK, and s41-s41CK, had the most differential genes in biological processes, followed by cellular components, and less in molecular functions. KEGG analysis showed that infection had a great influence on plant signal transduction, biosynthesis of secondary metabolites, lipid metabolism, amino acid metabolism, and sugar metabolism in sunflowers. (3) Physiological analyses found that the phenylalanine deaminase, cinnamyl alcohol dehydrogenase, glutathione, total phenols, and salicylic acid showed an upward trend, indicating that the stress tolerant system was activated under parasitism. However, the trend of the physiological indicators of the sensitive and tolerant materials were different. Also, the genes controlling the physiological responses were differentially expressed. [Conclusion] It was found that inoculation with broomrape significantly affected the plant height and root volume of the susceptible materials, while the resistant materials were not affected. The resistant materials were enhanced in root lignin synthesis, antioxidant enzyme activity, and the expression of key genes of phenylpropanoid metabolism, salicylic acid and signaling pathway, and hence increased the resistance to broomrape.

The seasonal drought is a serious problem because of the unevenly distributed rainfall during the years in the Yangtze River basin. To construct multi-cropping patterns of intercropping with drought avoidance and disaster reduction as the main body is the fundamental way to realize the efficient utilization of water resources. Therefore, we carried out dryland multiple cropping patterns evaluation in test in the Yangtze River (Sichuan, Hubei, Hunan, Jiangxi, and Jiangsu) from 2016 to 2020, the cropping patterns was set as wheat-summer maize (C1), wheat-summer maize summer soybean (C2), forage rape // -spring maize/summer soybean (C3), and potato-spring maize/summer soybean (C4) in Sichuan. Rape-maize summer soybean (B1), forage rape // -spring maize spring soybean (B2), and potato / spring maize / summer soybean (B3) in // Hubei; rape-maize su // mmer soybean (N1), forage rape-spring maize/summer soybean (N2), and forage rape-spring maize spring soybean // -autumn soybean (N3) in Hunan; potato/spring maize/summer soybean (X1), rape-maize summer soybean (X2), ryegrass //-spring maize/summer soybean (X3), and ryegrass-spring maize spring soybean (X4). Wheat // -fresh maize/fresh maize (S1), wheat-fresh maize/fresh soybean (S2), fresh broad bean/fresh maize-fresh maize (S3), and fresh broad bean/fresh maize-fresh soybean (S4) in Jiangsu. We compared the characteristics of supply-demand equilibrium, the paddy of the overall productions and the water benefits of different cropping patterns with the AquaCrop model. These results showed that the water satisfy rate of C4 was 5.28%, 2.91%, and 6.00% higher than C1, C2, and C4, and the paddy of the overall production was 71.2%, 49.3%, and 25.6% higher, respectively, and the water benefit was 329.29%, 123.42%, and 45.52% higher in Sichuan. The water satisfy rate of B3 was 3.99% and 3.51% higher than B1 and B2, and the paddy of the overall production was 36.8% and 25.8% higher, and the water benefit was 295.60% and 69.01% higher in Hubei, respectively. The water satisfy rate of N2 was 9.08% and 2.93% higher than N1 and N3, and the water benefit was 58.47% and 183.33% higher in Hunan, respectively. The water satisfy rate of X1 was 7.94%, 6.70%, and 4.05% higher than X2, X3, and X4, and paddy of the overall production was 112.4%, 152.5%, and 116.8% higher, respectively, and the water benefit was 97.03%, 126.14%, and 77.68% higher in Jiangxi, respectively. The water satisfy rate of S4 was 7.94%, 6.70%, and 4.05% higher than X2, X3, and X4, and paddy of the overall production was respectively 35.4%, 17.5%, and 12.6% higher, and the water benefit was 60.25%, 14.93%, and 45.56% higher in Jiangsu, respectively. Potato-spring maize/summer soybean in Sichuan, potato/spring maize/summer soybean in Hubei, forage rape-spring maize/summer soybean in Hunan, potato/spring maize/summer soybean in Jiangxi and fresh broad bean/fresh maize-fresh soybean in Jiangsu were the appropriate cropping patterns that can improve the water supply-demand equilibrium, paddy of the overall production, and water benefit. To avoid seasonal drought and achieve annual high yield, the appropriate multiple cropping patterns of intercropping should be selected depending on the rainfall conditions in the dryland of the Yangtze River basin. [ABSTRACT FROM AUTHOR]

In order to solve the problems of difficulty and low efficiency in selecting water resources allocation scheme, a multi-attribute Decision-making method of water resources allocation scheme based on Pythagorean fuzzy set with interval value and PROMETHEE algorithm is proposed in this paper. Firstly, the interval fuzzy decision matrix of decision-makers is constructed, and the weights of decision-makers and attributes are determined by the distance of relative proximity coefficient method, entropy method and Pythagorean fuzzy number. Secondly, the comprehensive weight and IVPFWA operator are used to aggregate the decision matrix of each decision-maker into the comprehensive matrix, and then the final ranking results of water resources allocation schemes are obtained by PROMETHEE method. Finally, the algorithm used in this paper to select the optimal water resources allocation plan in City S as a case, and through comparison with the results of other methods, it finally shows that the method in this paper can accurately determine a reasonable water resources allocation plan, and the method is effective and reliable. [ABSTRACT FROM AUTHOR]

Recommender systems can effectively alleviate the problem of information overload caused by the rapid development of the Internet. However, the occurrence of shilling attacks restricts the healthy development of recommender systems. Therefore, how to detect shilling attacks accurately and efficiently is an important problem in the field of recommender systems security. The existing detection methods usually design hand-crafted detection features based on expert knowledge or automatically learn features from a single perspective using deep learning, then the attack users are identified according to the extracted features by hard classification, resulting in the poor detection performance. By automatically learning features from multiple perspectives and introducing a hesitant fuzzy decision, a novel detection method based on CNN and hesitant fuzzy set was proposed and named CNN-HFS. Firstly, for each user, three behavior matrices were extracted from the perspectives of rating, preference and rating time, respectively. To reduce the influence of data sparse, these matrices were scaled by bicubic interpolation to correspondingly obtain a dense rating matrix, a dense preference matrix and a dense time matrix. Next, each scaling matrix of users was regarded as an image, and three different CNN classifiers were trained based on these scaling matrices in three different views respectively. For each user, three membership degrees to the classifier of attack users were calculated. Finally, a fuzzy hesitant set was introduced to make a comprehensive decision, and the attack users were identified according to the decision results. To validate the effectiveness of the proposed CNN-HFS, the extensive experiments were conducted on the MovieLens 1M and Amazon datasets. The evaluation metrics of precision, recall and F1-measure were used to compare the proposed method with SVM-TIA, CoDetector, CNN-SAD, SDAEs-PCA, CNN-R, CNN-P and CNN-T. The experimental results showed that the proposed method is superior to seven baseline methods in terms of three detection metrics and achieves an excellent detection performance under various attacks. [ABSTRACT FROM AUTHOR]

Cancer is a form of inflammation, which is different from common inflammation in that it is uncontrollable and difficult to identify pathogenic microorganisms. Most tumors are related to specific pathogenic microorganisms, especially viral infections. The relationship between gliomas and human cytomegalovirus (HCMV) infection has been debated for decades. This article puts forward the author's own point of view as an interpretation on the basis of objectively expounding the positive and negative points of view, and put forward a further solution to the dispute, for clinical reference. [ABSTRACT FROM AUTHOR]

The experiment was to study the effect of different storage temperatures on post-harvest physiology and quality of feed mulberry leaves, the mulberry leaves were stored at room temperature 26, 8, 4, and 0 °C to analyse the changes of mulberry leaf color, respiratory intensity, weight loss rate, protein content, total sugar content and fat content. The results showed that compared with normal temperature storage, low temperature storage could prolong the storage time of feed mulberry leaves, reduce weight loss, reduce respiration, delay color change, delay the decrease time of total sugar, protein and fat content. Under low temperature condition, 0 °C would cause frostbite of mulberry leaves, and mulberry leaves lose use value. Mildew appeared in mulberry leaves after 20 d of storage at 8 °C. Storage at 4 °C could prolong the storage period of mulberry leaves to 40 d. The experiment indicates that the storage effect of mulberry leaves at 4 °C is better than that under other test conditions, so 4 °C is more suitable for storing feed mulberry leaves. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) graphene was prepared by hard template method. After functionalized by 3-thiophenecarboxylicacid-5-ethyl-hydrazide,3D graphene was used as sensitive element and the ionic liquid 1 -ethyl-3 -methylimidazolium hexaffuorophosphate ( EMIPF6 ) was used as a binder to modify the glassy carbon electrode. The content of cadmium was determined by ASV method, and the results were compared with that of inductively coupled plasma mass spectrometry (ICP-MS), specified detection method for cadmium in Chinese Pharmacopoeia edition 2020. Results showed that under the optimal test condi-tions(0.2 mol/L HAc-NaAc,£d =-1.2 V,td =180 s),the ASV peak current was proportional to Cd2 + concentration in the range of 0 -4 mg/kg,and the limits of detection was 0.6 ng/kg( S/N = 3 ). The results of methodology met the requirements of the test method and the results were consistent with those determination results of inductively coupled plasma mass spectrometry (ICP-MS). The rapid determination of the heavy metal cadmium ion content in hawthorn. The method is simple,repeatable,sensitive and has [ABSTRACT FROM AUTHOR]

Background: Psychiatric patients are affected by diseases and mental symptoms that may worsen their ability to adjust emotionally. Being unable to respond to the emptiness, increases the risk of suicidal behaviors. Purpose: This study was designed to translate the Experienced Level of Existential Emptiness (ELEE) scale, developed by Hazell in 1984, from the original English into Chinese and then to test its reliability and validity. Methods: This research adopted a cross-sectional design and collected data using convenience sampling and a structured questionnaire. The subjects of this study were psychiatric outpatients in the acute and chronic wards of a psychiatric hospital in Taiwan. The instruments used in this research included a demographic datasheet; the ELEE; the University of California, Los Angeles Loneliness Scale, version 3; the Beck Depression Inventory-II; the State- Trait Anxiety Inventory Y form; and the Oxford Happiness Inventory. After the data were obtained, the reliability and validity of the Chinese-version scale was tested. Results: Three hundred subjects were surveyed. The content validity index value of the ELEE was between .88 and 1, and the retest reliability and intrinsic consistency were good. From the analysis of criterion-related validity, a higher degree of emptiness was shown to correlate with more-obvious feelings of loneliness, depression, and anxiety. Conversely, a higher sense of happiness was shown to correlate with less-obvious feelings of these three variables. After the construct validity test, which used confirmatory factor analysis and regarded the co-variation coefficient of association and model fit index as the basis of consideration, the scale was reduced to two sub-scales of seven questions each. After the deletion of items, the scale retained good retest reliability and intrinsic consistency, supporting the retention of the 14 questions in the scale. Conclusions/ Implications for Practice: The findings of this study support using the Chinese version of the ELEE to measure emptiness in patients with mental illness and then providing appropriate medical assistance based on the measured results. [ABSTRACT FROM AUTHOR]

The shape memory effect of Fe-Mn-Si based alloys could be significantly improved by thermo-mechanical treatments. In this work, the cast Fe-Mn-Si based alloy was hot forged, 20% cold rolled and solution treated, followed by annealing at 1073 K for different time on some specimens deformed by 10% at room temperature, and the effect of annealing time of thermo-mechanical treatments on the microstructures and shape memory effect of the Fe-Mn-Si based alloy was studied with the help of backscattered electron microanalysis (EBSD), RGM-4300 universal testing machine, differential four-terminal resistance method and bending method.Results show that the recovery strain of the solution-treated Fe-Mn-Si based alloy is 4.1%; when the annealing time of thermo-mechanical treatment is 10 min, the recovery strain is remarkably improved to 5.3%; As the annealing time of thermo-mechanical treatment is further prolonged, the recovery strain decreases; when the annealing time of thermo-mechanical treatments is 180 min, the recovery strain decreases to 4.9%. As the annealing time of thermo-mechanical treatments prolongs, the fraction of annealing twins increases, while the density of stacking faults decreases, which leads to the ability of facilitating stress-induced ε martensitic transformation and suppressing plastic glide weakening. This is the main reason why the recovery strain of the Fe-Mn-Si based alloy decreases with the annealing time of thermo-mechanical treatments prolonging.

The end face meshing worm drive with tapered roller envelope has many simultaneous meshing tooth pairs and can eliminate clearance. According to the gear meshing principle and differential geometry principle, the meshing mathematical model of the transmission pair is established, the worm tooth surface equation and meshing function are deduced, and the meshing performance calculation formula is obtained. Matlab software is used to analyze the effects of small end radius, throat diameter coefficient and half cone angle of cone on the meshing performance evaluation parameters of the transmission pair induced normal curvature, lubrication angle, relative entrainment speed and self rotation angle. The analysis results show that the transmission pair has good meshing performance.

Target recognition and temperature extraction of the typical component of gas insulated switchgear (GIS) are the key to realizing the infrared intelligent detection of equipment heating state. In this paper, an improved YOLOv4 algorithm based on convolutional block attention module (CBAM) is proposed to achieve rapid target detection and hot spot temperature extraction of GIS bus, disconnector and other components. Firstly, the original infrared images are acquired at a substation site, and an infrared dataset containing typical GIS components is constructed by sharpening the images and marking components. Then, the deep separable convolutional network is used to reduce the amount of model parameters, and the CBAM is integrated to optimize the recognition ability of the model, on the basis of which a GIS infrared component target rapid detection algorithm with improved YOLOv4 is constructed. Finally, the gray-scale difference method is used to extract the temperature value of the hot area for the detected typical target components of GIS. The results show that the proposed algorithm can achieve a recognition speed of 31.5 frame per second and an recognition accuracy of 82.3% on the GIS infrared feature dataset, which is significantly better than other target algorithms. The error between the calculated value and the measured value of temperature rise of GIS components is within ±1℃. The algorithm proposed in this paper can be deployed in edge intelligent terminals such as unmanned aerial vehicles and inspection trolleys to achieve refined identification and rapid diagnosis of the temperature rise status of on-site GIS equipment, thus improving the digitalization and intelligence level of health management of GIS.

[Purpose/Significance] The research paradigm of digital humanities provides an opportunity for researchers to conduct evidence-based research based on second-hand resources. The second-hand evidence in the evidence-based digital humanities research mainly refers to the secondary evidence obtained by researchers through analysis of the original literature records. Academic papers are such an example of second-hand evidence and analysis of these papers enables us to be focused on the exploration, discussion and comprehension of the specific evidence. [Method/Process] This paper aims to shed light on the theoretical basis related to second-hand evidence based digital humanities research, and conduct an empirical analysis with Dunhuang wooden and bamboo slips of Han Dynasty. Through the coding analysis of 287 relevant research papers downloaded from the CNKI database, the reliability and validity of the research were tested, and a comprehensive analysis of the category system was conducted. On this basis, two independent coders systematically coded all academic papersby, and a coding system was formed with reliable reliability and validity. This coding system provided us a foundation to summarize the procedure of extracting the second-hand evidence from academic papers in the digital humanities research. [Results/Conclusions] This paper issued a three-stage and five- link procedure for second-hand evidence based digital humanity research. The "three stages" refer to the systematical literature retrieval, category formulation and comprehensive analysis of the second-hand evidence elements and the five links include evidence retrieval, reliability test, validity test, category construction and evidence element synthesis. The procedure developed by this research is expected to shed light on the knowledge organization of ancient literature works and lay a foundation for the digital humanities research based on the secondary resources like academic papers. Thus, based on the above procedure, the researchers in the digital humanities area are able to extract fruitful second-hand evidence from secondary resources (academic papers, for example) instead of acquiring initial evidence. This procedure may benefit the evidence-based digital humanity research because it is always a challenging task for individual researcher to access the initial research material like Dunhang wooden and bamboo slips of Han Dynasty. In summary, the paradigm constructed in this study has certain theoretical reference and practical guidance value for the construction of evidence-based digital humanities subject, and academic and discourse system. Thus, it is expected to benefit the construction of independent knowledge system of evidence-based digital humanities with Chinese characteristics.

Objective To explore the expression of 3-hydroxymethylglutaryl-CoA synthase 2 (HMGCS2) and its correlation with the clinicopathological characteristics of patients with bladder cancer. Methods The GEO database was used to screen genes that were significantly differentially expressed between muscle invasive bladder cancer and non-muscle invasive bladder cancer. The survival analysis of the screened public differentially expressed genes was performed by gene expression profiling interactive analysis (GEPIA). The Metascape database was used for the functional enrichment analysis of HMGCS2 and its related genes. The expression of HMGCS2 was detected with immunohistochemical staining in clinical samples from patients with bladder cancer. Chi-square test was used to analyze the relationship between the expression of HMGCS2 and the clinicopathological characteristics, and Cox regression analysis was adopted to verify the prognostic efficacy of HMGCS2. Results The transcriptome data of the GEO database showed HMGCS2 had significantly lower expression in muscle invasive bladder cancer compared with non-muscle invasive bladder cancer (7.42±2.51 vs 9.38±2.78, P < 0.05). The survival analysis of the GEPIA database showed that patients with high expression of HMGCS2 had better prognosis (overall survival: HR=0.6, P=0.028; disease progression-free survival: HR=0.59, P=0.036); KEGG pathway analysis and GO functional enrichment analysis showed that HMGCS2 might be involved in fat metabolism, cell apoptosis and platinum resistance, and exerted effect on the signal transduction of the mTOR pathway. In addition, the Chi-square test showed the expression of HMGCS2 was significantly related to the T stage (P < 0.001), tissue grade (P=0.006), patients' overall survival status (P < 0.001) and patients' disease-free survival status (P < 0.001); Univariate Cox regression analysis showed that HMGCS2 was related to the patients' overall survival rate and the disease progression-free survival rate (OS: HR=0.104, P < 0.001; DFS: HR=0.155, P < 0.001); multivariate Cox regression analysis indicated that HMGCS2 was an independent predictor of the prognostic risk of patients (OS: HR=0.181, P < 0.001; DFS: HR=0.312, P < 0.001). Conclusion HMGCS2 is lowly expressed in muscle invasive bladder cancer, and its low expression is closely related to the poor prognosis of patients.

Objective To screen the influencing factors of liver cirrhosis with spontaneous bacterial peritonitis (SBP) so as to establish and verify a diagnostic model of cirrhosis with SBP. Methods A total of 7 461 patients with liver cirrhosis were collected from 2 Grade-A hospitals in Chongqing (Hospital A and B) between July 2015 and December 2019. According to the occurrence of SBP during hospitalization, they were divided into SBP (n=1 173) and non-SBP (n=6 288) groups. A total of 3 776 patients (70%) from Hospital A were randomly selected as the training set, while the remaining 1 619 patients (30%) and the 2 066 patients from hospital B were subjected as the internal and external validation sets respectively. Univariate and logistic analyses were used to screen variables, and logistic regression, random forest (RF), decision tree (DT) and XGBoost models were subsequently established using the training set. Then, the optimized logistic regression model was built on the basis of the above 4 models. Finally, the 5 models were applied in the internal and external verification sets for evaluating and comparing the diagnostic value of different models for cirrhosis with SBP. Results The machine learning algorithm suggested that the 7 common influencing factors with significance in all models were as follows: decompensation stage (OR=5.354, 95%CI: 3.770-7.803), lymphocyte percentage (OR=0.951, 95%CI: 0.939-0.962), total bilirubin (OR=1.003, 95%CI: 1.002-1.004), abnormal C-reactive protein (OR=1.626, 95%CI: 1.310-2.017), international normalized ratio (OR=1.346, 95%CI: 1.091-1.681), prealbumin (OR=0.990, 95%CI: 0.987-0.993) and model for end stage liver disease (MELD) score (OR=1.038, 95%CI: 1.015-1.063). The AUC of the internal verification of the optimized logistic model was 0.860, with a sensitivity of 0.872 and a specificity of 0.719; while the corresponding values of the external verification were 0.818, 0.662 and 0.812, respectively. Delong test showed that there was no statistical difference in AUC between the optimized logistic regression model and the other models with favorable performance. Conclusion The risk prediction models established by machine learning algorithm for liver cirrhosis complicated with SBP have high diagnostic value. Among them, the optimized logistic regression model has performed well in both internal and external verification, and is able to provide reference for clinical diagnosis of SBP.

Peanuts were hydrolyzed step by step with various enzymes to prepare protein powder. Using peanuts as raw materials, protein extraction rate response value, enzyme addition amount, temperature, and pH as experimental factors, were used to establish a data model to optimize the extraction process with response surface. The protein powder prepared under this condition was compared with the protein powder prepared by water extraction method, single enzyme extraction method and commercially available protein. The particle size distribution, solubility, emulsification and surface hydrophobicity of protein powder extracted by compound enzyme were studied. The results showed that the optimal enzymatic hydrolysis conditions of the complex enzyme were 1.8% enzyme addition, 55 ℃ reaction temperature, and pH 9.2. Under these conditions, the protein extraction rate reached 89.21%. The particle size distribution of the protein powder prepared by the complex enzymes was uniform, and the particles were smaller, indicating that the protein solubility and emulsification were significantly improved.

With the continuous improvement of the performance of unmanned aerial vehicles and the extensive use of tactical methods, the cooperative operation of unmanned aerial vehicles (UAV) swarm has brought new challenges to the current air defense system. By combing and analyzing the application cases of UAV swarm warfare in recent years, this paper summarizes the characteristics of current UAV swarm warfare application, and explains the necessity and urgency of developing anti UAV swarm warfare command and control system. In addition, this paper analyzes the current situation of the command and control system of anti UAV swarm warfare in the world's military powers, and on this basis, puts forward some enlightenment suggestions for the development of the future anti UAV swarm warfare command and control system.

The main functional components and biological activities of Grifola frondosa were reviewed, and the existing problems and future research directions were also discussed.

研究旨在透過文獻分析，回顧過去國外科學教育領域中的系統思考能力相關研究，歸納其適用年級與學科、系統思考能力分析架構，以及評量與教學的趨勢並提出建議。研究者於 SCOPUS 與 Web of Science 資料庫搜尋 2000 年到 2019 年的英文期刊論文，經有系統篩選後，針對 20 篇文章進行分析。分析結果發現，系統思考的研究對象以國、高中生為主，有些研究以小學生為對象，其學習成效主要在基礎系統思考能力的獲得。涉及的學科領域則以生態、生物以及地科最為常見，所回顧的文獻中並沒有應用於物理領域，顯示系統思考並非適合融入所有自然科學領域。對於系統思考能力的分析架構，共可歸納出組件連結模式、階層發展模式、複雜系統模式及內容導向模式等四種類型。在系統思考量測方法上許多研究採多元評量，最常被採用的是開放性試題與晤談。至於教學策 略，許多研究都採取了多元的教學活動，且多半包含知識統整活動，部分研究則採用電腦模擬進行教學。由於文獻中已有較為完整的系統思考能力分析架構，未來建議可以進行學習進程或是縱貫性研究，並將資訊科技應用於系統思考評量上。最後，我們對系統思考在教學與評量的實務建議包含有：教學上應優先嘗試初階的組件連結模式；教學方法則以明示教學法協助學生建立系統思考概念鷹架、嘗試採用多元的活動設計、引進科技輔助以及引導學生廣泛地將系統思考應用於各種生活情境中；評量方面則是建議以概念圖、概念繪圖及概念填空題進行，容易實施且能獲得較多訊息。 The aim of this research was to review past empirical studies about systems thinking in science education in order to understand the applied grade levels and subject areas, the analytical framework for systems thinking, and its trends in teaching and assessment. We searched for research articles published from 2000 to 2019 in the SCOPUS and Web of Science database and found 20 qualified studies. The results showed that most studies were conducted at junior high schools and senior high schools. Some studies were conducted at the elementary school level and found gains in fundamental competence of systems thinking. The most frequently applied subject areas were ecology, biology, and earth science. In this review, no studies applied systems thinking in physics. This indicates that systems thinking might not be suitable for all subject areas of science. In terms of the analytical framework for systems thinking, different studies invented different frameworks. The common features of the systems thinking framework include components recognition, as well as the mutual interactions and influence of different components. Regarding assessment for systems thinking, some studies used multiple assessments, and the most commonly used types of assessments were open-ended questions and interviews. Many studies adopted a variety of teaching activities and included knowledge integration activities. Some studies also used computer simulations to support learning. For future research, we suggest investigating the learning progression of systems thinking or conducting longitudinal studies by applying the available analytical framework of systems thinking. Future studies can also apply computer technology in the assessment of systems thinking. Finally, we offer some specific suggestions for teaching and assessments of systems thinking.

BACKGROUND At present, the content of Se in soil is mainly determined by atomic fluorescence spectrometry, which has disadvantages such as large usage of acid and relatively complex pretreatment. Determination of high content of Se requires high dilution, which expands the analysis error. OBJECTIVES To establish a method for the determination of Se and other elements in Se-rich soil samples by wavelength dispersive and energy dispersive X-ray fluorescence (WD-ED XRF). METHODS WD-ED XRF was used to determine 17 major and minor elements such as Se in Hubei selenium-rich soil samples with powder pellet. While 10 elements were analyzed by WD-XRF, As, Cu, Rb, Sr, Zr, Ba, Ni were analyzed by ED-XRF, which significantly reduced the measurement time. RESULTS By mixing different certified reference materials in proportion to configure mixed certified reference materials, the problem of insufficient content of the existing Se reference materials in the range of 5-72μg/g was solved. For the determination of high content Se, the relative standard deviation was less than 10%, and the RSD of high content Se sample was less than 0.70%, through the precision and accuracy assessment. CONCLUSIONS The proposed method satisfies the quantitative analysis of soil samples with Se content greater than 3.00μg/g, and provides the quantitative or approximate quantitative analysis results of 16 major and minor elements.

Wavelength Division Multiplexing (WDM) system has been evolving and upgrading in the direction of high speed, long distance and large capacity. In recent years, with the maturity of high-speed optoelectronic devices, the research and application of beyond 400 Gbit/s has made a rapid progress. Based on the technical status and requirements of 800 Gbit/s transmission systems, this paper discusses the key technical problems, sorts out the latest developments in standardization research. The evolution and application of 800 Gbit/s optical systems is further discussed.

Wavelength Division Multiplexing (WDM) system has been evolving and upgrading in the direction of high speed, long distance and large capacity. In recent years, with the maturity of high-speed optoelectronic devices, the research and application of beyond 400 Gbit/s has made a rapid progress. Based on the technical status and requirements of 800 Gbit/s transmission systems, this paper discusses the key technical problems, sorts out the latest developments in standardization research. The evolution and application of 800 Gbit/s optical systems is further discussed.

Considering the cost and large power consumption of high-resolution analog-to-digital converters in mmWave massive Multiple Input Multiple Output (MIMO) system, we develop a channel estimation algorithm with one-bit quantizer. Given the quantized received signal, the conditional expectation is first calculated to estimate the unquantized received signal. Based on the sparsity of mmWave channel in the angular domain, the column most correlative to the current residual is selected for least square estimation in each iteration. We also propose a solution to select multiple atoms in each iteration for the efficiency improvement. The simulation results show that the average normalized mean square error of the proposed algorithm and the running time of each iteration are 1/10 and 1/20 of the Expectation Maximization (EM) algorithm. It can be seen that the algorithm has improved performance and higher reliability, with certain practical value in the channel estimation application of mm-Wave large-scale MIMO systems.

The COVID-19 pandemic led to significant burnout among nurses, resulting in a shortage of nursing staff. Issues related to nursing work have received significant attention recently, and only healthy nurses are capable of providing good quality patient care. The authors employed Bronfenbrenner's Ecological System Theory to analyze the impact of the COVID-19 pandemic on nurses and proposed specific strategies and recommendations to enhance the nursing workplace. Under the Ecological System Theory, several factors, including inadequate preparedness, dangerous working environment, work-family conflicts, discrimination due to public panic, and health damage, contribute to nurse burnout. Whether during or after the COVID-19 pandemic, it is necessary to provide education programs to enhance the professional abilities of nurses, foster policies that promote a positive practice work environment, implement a triage system based on the severity of patients, elevate the image of the nursing profession, monitor the health of nurses, and advocate for transformational leadership. The nursing workplace should help nurses gain greater confidence and improve their ability to handle various workplace challenges. In the future, medical institutions should provide a better work environment for nurses and expect the public to pay more attention to the development of the nursing profession.

Sepsis-associated encephalopathy (SAE) refers to diffuse brain dysfunction caused by sepsis, which is characterized by decreased attention, directional impairment, being prone to irritation, and in severe cases the patient will experience drowsiness and coma. The pathogenesis of SAE mainly includes neuroinflammation, damage of blood-brain barrier, cerebral vascular dysfunction, and neurometabolic changes, among which neuroinflammation is the core pathological process. Microglia are considered to be important immune cells of the central nervous system and play an important role in neuroinflammation. This article systematically describes the role of microglia in the development of SAE, and discusses the phenotype and related signaling pathways of microglia, in order to clarify the role of microglia in SAE and provide a theoretical basis for clinical treatment of SAE.

Objectives: To understand the growth and development status and differences between small for gestational age (SGA) and appropriate for gestational age (AGA) preterm infants during corrected ages 0-24 months, and to provide a basis for early health interventions for preterm infants., Methods: A retrospective study was conducted, selecting 824 preterm infants who received regular health care at the Guangzhou Women and Children's Medical Center from July 2019 to July 2022, including 144 SGA and 680 AGA infants. The growth data of SGA and AGA groups at birth and corrected ages 0-24 months were analyzed and compared., Results: The SGA group had significantly lower weight and length than the AGA group at corrected ages 0-18 months ( P <0.05), while there were no significant differences between the two groups at corrected age 24 months ( P >0.05). At corrected age 24 months, 85% (34/40) of SGA and 79% (74/94) of AGA preterm infants achieved catch-up growth. Stratified analysis by gestational age showed that there were significant differences in weight and length at corrected ages 0-9 months between the SGA subgroup with gestational age <34 weeks and the AGA subgroups with gestational age <34 weeks and 34 weeks ( P <0.05). In addition, the weight and length of the SGA subgroup with gestational age 34 weeks showed significant differences compared to the AGA subgroups with gestational age <34 weeks and 34 weeks at corrected ages 0-18 months and corrected ages 0-12 months, respectively ( P <0.05). Catch-up growth for SGA infants with gestational age <34 weeks and 34 weeks mainly occurred at corrected ages 0-12 months and corrected ages 0-18 months, respectively., Conclusions: SGA infants exhibit delayed early-life physical growth compared to AGA infants, but can achieve a higher proportion of catch-up growth by corrected age 24 months than AGA infants. Catch-up growth can be achieved earlier in SGA infants with a gestational age of <34 weeks compared to those with 34 weeks.

Objective: In this study, we used artificial intelligence (AI) technology to explore for automated medical record quality control methods, standardize the process for medical record documentation, and deal with the drawbacks of manually implemented quality control., Methods: In this study, we constructed a medical record quality control system based on AI. We first designed and built, for the system, a quality control rule base based on authoritative standards and expert opinions. Then, medical records data were automatically collected through a data acquisition engine and were converted into structured data through a post-structured engine. Finally, the medical record quality control engine was combined with the rule base to analyze the data, identify quality problems, and realize automated intelligent quality control. This system was applied to the quality control of medical records and five quality control points were selected, including similarities in the history of the present illness, defects in the description of chief complaints, incomplete initial diagnosis, missing in formation in the history of menstruation, marriage, and childbirth, and mismatch between the chief complaints and the history of the present illness. We randomly selected 2 918 medical records of patients discharged in January 2022 to conduct AI quality control. Then we organized medical record quality control experts to conduct an accuracy review, made a comparison with previous manual quality control records, and analyzed the results. The number of quality problems that were verified in the accuracy review was taken as the gold standard and receiver operating characteristic (ROC) curves were drawn for the 5 quality control points., Results: According to the accuracy review performed by medical record quality control experts, the accuracy of AI quality control reached 89.57%. For the sampled medical records, the results of AI quality control were compared with those of previous manually performed quality control and only one problem detected by manual quality control of the sampled medical records was not detected by the AI quality control system. The number of medical record quality problems correctly detected by AI quality control was about 2.97 times that of manual quality control. Analysis of the ROC curves showed that the AUC of the five quality control points of the AI quality control system were statistically significant ( P <0.05) and all the AUC values approximated or exceeded 0.9. In contrast, results obtained through manually performed quality control found significant AUC (0.797) for only one quality control point-similarities in the history of present illness ( P <0.05). Comparison of the AUC values of the two quality control methods showed that AI quality control system had an advantage over manually performed quality control for the five quality control points., Conclusion: Through the application of medical record quality control system based on AI, efficient full quality control of medical record documentation can be achieved and the detection rate of quality problems can be effectively improved. In addition, the system helps save manpower and improve the quality of medical record documentation., Competing Interests: 利益冲突　所有作者均声明不存在利益冲突, (© 2023《四川大学学报（医学版）》编辑部 版权所有Copyright ©2023 Editorial Board of Journal of Sichuan University (Medical Sciences).)

Objectives: To explore the molecular characteristics of Staphylococcus aureus ( S. aureus ) in children, and to compare the molecular characteristics of different types of strains (infection and colonization strains) so as to reveal pathogenic molecular markers of S. aureus ., Methods: A cross-sectional study design was used to conduct nasopharyngeal swab sampling from healthy children in the community and clinical samples from infected children in the hospital. Whole genome sequencing was used to detect antibiotic resistance genes and virulence genes. A random forest method to used to screen pathogenic markers., Results: A total of 512 S. aureus strains were detected, including 272 infection strains and 240 colonization strains. For virulence genes, the carrying rates of enterotoxin genes ( seb and sep ), extracellular enzyme coding genes ( splA , splB , splE and edinC ), leukocytotoxin genes ( lukD , lukE , lukF-PV and lukS-PV ) and epidermal exfoliating genes ( eta and etb ) in infection strains were higher than those in colonization strains. But the carrying rates of enterotoxin genes ( sec , sec3 , seg , seh , sei , sel , sem , sen , seo and seu ) were lower in infection strains than in colonization strains ( P <0.05). For antibiotic resistance genes, the carrying rates of lnuA , lnuG , aadD , tetK and dfrG were significantly higher in infection strains than in colonization strains ( P <0.05). The accuracy of cross-validation of the random forest model for screening pathogenic markers of S. aureus before and after screening was 69% and 68%, respectively, and the area under the curve was 0.75 and 0.70, respectively. The random forest model finally screened out 16 pathogenic markers ( sem , etb , splE , sep , ser , mecA , lnuA , sea , blaZ , cat(pC233) , blaTEm-1A , aph(3')-III , ermB , ermA , ant(9)-Ia and ant(6)-Ia ). The top five variables in the variable importance ranking were sem ( OR =0.40), etb ( OR =3.95), splE ( OR =1.68), sep ( OR =3.97), and ser ( OR =1.68)., Conclusions: The random forest model can screen out pathogenic markers of S. aureus and exhibits a superior predictive performance, providing genetic evidence for tracing highly pathogenic S. aureus and conducting precise targeted interventions.

Objectives: To investigate the difference in the therapeutic effect of mycophenolate mofetil (MMF) or cyclophosphamide (CTX) in children with Henoch-Schönlein purpura nephritis (HSPN) of different age groups., Methods: A retrospective analysis was conducted on the clinical data of 135 children with HSPN who were treated with MMF or CTX in the Department of Nephrology, Children's Hospital Affiliated to Capital Institute of Pediatrics, from October 2018 to October 2020. According to the immunosuppressant used, they were divided into two groups: MMF group and CTX group, and according to the age, each group was further divided into two subgroups: ≤12 years and >12 years, producing four groups, i.e, the ≤12 years MMF subgroup ( n =30), the >12 years MMF subgroup ( n =15), the ≤12 years CTX subgroup ( n =71), and the >12 years CTX subgroup ( n =19). All children were followed up for at least 12 months, and the above groups were compared in terms of clinical outcomes and the incidence rate of adverse reactions., Results: There was no significant difference in the complete response rate between the MMF group and the CTX group after 3, 6, and 12 months of treatment ( P >0.05). There were no significant difference in the complete response rate and the incidence rate of adverse reactions between the >12 years MMF subgroup and the ≤12 years MMF subgroup at 3, 6, and 12 months of treatment ( P >0.05). The >12 years CTX subgroup had a significantly lower complete response rate than the ≤12 years CTX subgroup at 6 and 12 months of treatment ( P <0.05). The >12 years CTX subgroup had a significantly higher incidence rate of adverse reactions than the >12 years MMF subgroup ( P <0.05)., Conclusions: The efficacy and adverse reactions of MMF are not associated with age, but the efficacy of CTX is affected by age, with a higher incidence rate of adverse reactions. CTX should be selected with caution for children with HSPN aged >12 years.

Objective: To explore the clinical and genetic characteristics of a boy with isolated maternal uniparental disomy of chromosome 20 [UPD(20)mat]., Methods: A child who was admitted to the Tongji Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology on April 8,2021. was selected as the study subject. Phenotypic and endocrinological findings of the child were retrospectively analyzed. Whole exome sequencing (WES) and methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) were carried out for detecting the UPD sequences and copy number variations. Both of his parents were verified by Sanger sequencing. Relevant literature was systematically reviewed., Results: The child, a 3-year-and-8-month-old boy born to a 41-year-old mother by Cesarean delivery at 36 +2 gestational weeks due to oligohydramia, had a birth weight of 2 300 g and length of 46 cm. He was admitted to the NICU for feeding difficulties which had persisted despite of clinical management. At the age of 3.75, he had a height of 92.5 cm (< 3rd percentile; 25th ~ 50th percentile at 2.5 years) and a weight of 10.8 kg (< 3rd percentile; 50th percentile at 15 months). He had also presented with growth retardation, short stature, attention deficit and hyperactivity disorder (ADHD), mild mental retardation, and speech and language development disorders. He had simian creases in both hands but no additional dysmorphic signs, and his motor development was normal. Serum insulin, thyroid-stimulating hormone, and insulin growth factor binding protein 3 levels were within the normal ranges, though insulin growth factor-1 (IGF-1) was slightly decreased. Since that time he had continuously used atomoxetine hydrochloride capsules to control his ADHD. WES and MS-MLPA revealed the existence of UPD (20)mat., Conclusion: The UPD(20)mat syndrome is characterized by feeding difficulties, growth retardation and short stature. The child in our case has been accompanied by ADHD and speech and language development disorders, which required long-term treatment. For women with advanced maternal age and suggestive phenotypes, genetic testing and counseling should be conducted.

To explore the effects of single or combined application of chlorine-and sulfur-based fertilizers on rice bioavailability of Cd in soils, pot experiments with reddish clayey soil (developed from quaternary red clay parent materials) under three exogenous Cd levels (0, 0.5, and 2.0 mg·kg -1 ) were conducted. Meanwhile, chlorine-based fertilizers (KCl, NH 4 Cl) and sulfur-based fertilizers[K 2 SO 4 , (NH 4 ) 2 SO 4 ] were added in different proportions. The soil pH, Cd morphology, and Cd accumulation in rice at different growth stages were analyzed. The results revealed that both chlorine-and sulfur-based fertilizers could acidify the soil; however, the effect of chlorine-based fertilizers was more significant. During the filling stage of rice, the soil pH value of the treatment of applying single chlorine-based fertilizer decreased by 0.28 on average compared with that of applying single sulfur-based fertilizer. At the maturity stage of rice, chlorine-based fertilizer could activate the residual Cd, whereas sulfur-based fertilizer passivated the acid-extracted Cd to its residual state. Compared with the single application of the same fertilizer, the combined application of chlorine-and sulfur-based fertilizers was more likely to promote the accumulation of Cd in rice plants. The highest Cd accumulation of brown rice was 0.21 mg·kg -1 (2.0 mg·kg -1 exogenous Cd level) in the 1:1 (mole ratios of Cl:S) treatment of chlorine-and sulfur-based fertilizers, which was 16.4% higher than that of single chlorine-based fertilizer and 113.3% higher than that of single sulfur-based fertilizer. Therefore, the combined application of chlorine-fertilizers and sulfur-based fertilizers will increase the concentration of Cd in brown rice. To ensure food quality and safety, it is more advisable to apply single sulfur-based fertilizer for rice planting.

This study utilized evidence mapping methodology to systematically identify, describe, and evaluate the evidence from relevant research on traditional Chinese medicine(TCM) interventions in patients with pulmonary fibrosis. CNKI, Wanfang, VIP, SinoMed, PubMed, Web of Science, EMbase, and Cochrane Library were searched from database inception to March 2023 for systematic reviews/Meta-analysis/network Meta-analysis on TCM interventions in pulmonary fibrosis. The quality of included studies was assessed using the AMSTAR 2 scale, and the evidence mapping approach was employed to present comprehensive information on populations, intervention methods, the sample size in systematic reviews/Meta-analysis, and conclusion classifications. Ultimately, 44 systematic reviews/Meta-analysis/network Meta-analysis were included. Apart from syndrome differentiation and treatment, TCM injections accounted for a significant proportion of the observed interventions. The treatment methods were mainly focused on nourishing Qi and Yin, promoting blood circulation, resolving stasis, and dredging collaterals. The results from the included studies demonstrated that TCM treatment for pulmonary fibrosis could improve efficacy, increase lung function, improve PaO&#95;(2 )levels, increase the 6-minute walk distance(6MWD), alleviate clinical symptoms, and enhance patients' quality of life. Based on the assessment using the AMSTAR 2 scale, methodological issues were identified, including the lack of protocol registration, failure to provide a list of excluded literature, and incomplete explanations regarding the impact of heterogeneity and bias on the results. The evidence mapping revealed that 42 conclusions were beneficial, while two conclusions were potentially beneficial. Overall, the quality of evidence was relatively low, primarily due to methodological imprecision and publication bias. Although TCM showed certain efficacy in the treatment of pulmonary fibrosis, the quality of reported literature, methodological quality, and overall evidence quality need improvement. It is recommended to conduct high-quality and standardized studies in the future to provide better evidence-based guidance.

Since December 2019, coronavirus disease 2019 (COVID-19) has been rapidly spreading worldwide and affecting the physical and mental health of the general population. It may have even more serious potential harm to children with autism spectrum disorder (ASD). This paper provides a literature review on the psychological and behavioral problems experienced by children with ASD during the COVID-19 epidemic, as well as the factors influencing these issues. The findings of this review can serve as a basis for clinical research on ASD children.

Nitrogen (N) deposition in the context of human activities continuously affects the carbon cycle of ecosystems. The effect of N deposition on soil organic carbon is related to the differential responses of different carbon fractions. To investigate the changes in soil organic carbon fraction and its influencing factors in the context of short-term N deposition, four N addition gradients:0 (CK), 1.5 (N1), 3 (N2), and 6 (N3) g·(m 2 ·a) -1 were set up in acacia plantations based on field N addition experiments, and the soil physicochemical properties, microbial biomass, and enzyme activities were measured in June and September. The results showed that:① exogenous N input reduced soil pH, promoted the increase in soluble organic carbon content, and increased soil nitrogen effectiveness. ② Short-term N addition significantly reduced soil organic carbon content, and the response of each component of organic carbon to N addition was different. Among them, the content of easily oxidized organic carbon was significantly reduced and reached the lowest value under the N2 treatment, with 54.4% and 48.2% reduction compared with that of the control, respectively, and the content of inert organic carbon increased, although the increase was not significant. Nitrogen addition reduced the soil carbon pool activity and improved the stability of the soil carbon pool. Soil carbon pool activity reached its lowest under the N3 and N2 treatments, with a decrease of 53.3% and 52.80%, respectively, compared to that of the control. ③Random forest modeling indicated that the soil microbial biomass stoichiometry ratio, microbial biomass carbon, and AP were the key factors driving the changes in soil organic carbon activity under short-term N addition, explaining 65.96% and 66.68% of the changes in oxidizable organic carbon and inert organic carbon, respectively. Structural equation modeling validated the results of the random forest modeling, and soil microbial biomass stoichiometric ratios significantly influenced carbon pool activity. Short-term nitrogen addition changed soil microbial biomass and its stoichiometric ratio in the acacia plantation forest mainly through two pathways, i.e., increasing soil nitrogen effectiveness and promoting soil acidification and inhibiting extracellular carbon hydrolase activity, thus changing the soil carbon fraction ratio and participating in the soil organic carbon cycling process.

Objectives: To study the safety and short-term effectiveness of blinatumomab in the treatment of childhood relapsed/refractory acute lymphoblastic leukemia (R/R-ALL)., Methods: Six children with R/R-ALL who received blinatumomab treatment from August 2021 to August 2022 were included as subjects, and a retrospective analysis was performed for their clinical data., Results: Among the six children, there were three boys and three girls, with a median age of 10.5 (5.0-13.0) years at the time of inclusion. Of all six children, one had refractory ALL and did not achieve remission after several times of chemotherapy, and 5 relapsed for the first time, with a median time of 30 (9-60) months from diagnosis to relapse. Minimal residual disease (MRD) before treatment was 15.50% (0.08%-78.30%). Three children achieved complete remission after treatment, among whom two had negative conversion of MRD. Five children had cytokine release syndrome (CRS), among whom 3 had grade 1 CRS and 2 had grade 2 CRS. Four children were bridged to allogeneic hematopoietic stem cell transplantation, with a median interval of 50 (40-70) days from blinatumomab treatment to transplantation. The six children were followed up for a median time of 170 days, and the results showed an overall survival rate of 41.7% (95% CI : 5.6%-76.7%) and a median survival time of 126 (95% CI : 53-199) days., Conclusions: Blinatumomab has good short-term safety and effectiveness in the treatment of childhood R/R-ALL, and its long-term effectiveness needs to be confirmed by studies with a larger sample size.

Objectives: To investigate the clinical features of juvenile myelomonocytic leukemia (JMML) and their association with prognosis., Methods: Clinical and prognosis data were collected from the children with JMML who were admitted from January 2008 to December 2016, and the influencing factors for prognosis were analyzed., Results: A total of 63 children with JMML were included, with a median age of onset of 25 months and a male/female ratio of 3.2∶1. JMML genetic testing was performed for 54 children, and PTPN11 mutation was the most common mutation and was observed in 23 children (43%), among whom 19 had PTPN11 mutation alone and 4 had compound PTPN11 mutation, followed by NRAS mutation observed in 14 children (26%), among whom 12 had NRAS mutation alone and 2 had compound NRAS mutation. The 5-year overall survival (OS) rate was only 22%±10% in these children with JMML. Of the 63 children, 13 (21%) underwent hematopoietic stem cell transplantation (HSCT). The HSCT group had a significantly higher 5-year OS rate than the non-HSCT group (46%±14% vs 29%±7%, P <0.05). There was no significant difference in the 5-year OS rate between the children without PTPN11 gene mutation and those with PTPN11 gene mutation (30%±14% vs 27%±10%, P >0.05). The Cox proportional-hazards regression model analysis showed that platelet count <40×10 9 /L at diagnosis was an influencing factor for 5-year OS rate in children with JMML ( P <0.05)., Conclusions: The PTPN11 gene was the most common mutant gene in JMML. Platelet count at diagnosis is associated with the prognosis in children with JMML. HSCT can improve the prognosis of children with JMML.