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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.

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 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.

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 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.