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The estuarine area of Luanhe River is an important fisheries ground in China's Bohai Sea. In 2016, Tangshan Marine Ranching Co., Ltd. constructed a 2 km2 artificial oyster–macroalgae reef area by placing artificial reefs on the seabed adjacent to the Luanhe River Estuary. This action resulted in sustainable annual economic outputs through the fishing and sea cucumber put-and-take fishery. Although Luanhe River runoff and reef construction are important to the local phytoplankton community and fisheries' production, little is known about how these factors affect phytoplankton community structure in the local coastal ecosystem. In this study, we conducted field surveys to investigate the spatiotemporal variations in species composition, abundance, dominant species, diversity indexes, niche width and overlap, and interspecific connection of the phytoplankton community in the ecosystem of oyster–macroalgal reefs. From July 2016 to August 2017, we collected data before and after reef construction in areas inside and outside of the benthic reefs in both the flood and dry seasons of Luanhe River runoff. We found a total of 79 species, with the majority represented by diatoms and dinoflagellates. The dominant species were Paralia sulcata and Coscinodiscus sp. The total species number and abundance increased from May to September. The species number in the reef area was greater than that outside the reef. Species abundance from August to September was greater in the reef area than in the control area, which was opposite the situation from May to June. We found more phytoplankton abundance in the flood season compared with that in the dry season. Our results suggest that reef construction can benefit the local phytoplankton community and that further studies of the relationship among oysters, macroalgae, and phytoplankton in the system are warranted. Moreover, we provide baseline data about variations in the phytoplankton community in a sea ranch area. [ABSTRACT FROM AUTHOR]

The prevalence of antimicrobial resistance reduces the effectiveness of antimicrobial drugs in the prevention and treatment of infectious diseases caused by pathogens such as bacteria, fungi, and viruses. Microbial secondary metabolites have been recognized as important sources for new drug discovery and development, yielding a wide range of structurally novel and functionally diverse antimicrobial drugs for the treatment of a variety of diseases that are considered good producers of novel antimicrobial drugs. Bacteria produce a wide variety of antimicrobial compounds, and thus, antibiotics derived from natural products still dominate over purely synthetic antibiotics among the antimicrobial drugs developed and introduced over the last four decades. Among them, Pseudomonas aeruginosa secondary metabolites constitute a richly diverse source of antimicrobial substances with good antimicrobial activity. Therefore, they are regarded as an outstanding resource for finding novel bioactive compounds. The exploration of antimicrobial compounds among Pseudomonas aeruginosa metabolites plays an important role in drug development and biomedical research. Reports on the secondary metabolites of Pseudomonas aeruginosa, many of which are of pharmacological importance, hold great promise for the development of effective antimicrobial drugs against microbial infections by drug-resistant pathogens. In this review, we attempt to summarize published articles from the last twenty-five years (2000–2024) on antimicrobial secondary metabolites from Pseudomonas aeruginosa. [ABSTRACT FROM AUTHOR]

Wire icing events pose a significant threat to the southern power grid's transmission lines in China. Fifteen such events were identified from 2018 to 2020 on the Guilin-Haiyang Mountain transmission line. Hourly measurements of ice thickness and concurrent meteorological data were analyzed using the Makkonen model's freezing rate formula to categorize the events into distinct growth patterns: dry and wet. The relationship between wire icing and meteorological factors across different micro-topography (windward slope, leeward slope, and pass) was further explored. Several key conclusions can be drawn. First, the altitude is positively correlated to the icing thickness, but relatively independent of the icing rate; however, such independence between the icing rate and altitude cannot be interpreted by the negative correlation of altitude with temperature and the positive relationship between wind speed and liquid water content. Second, a pronounced connection of the icing rate with meteorological factors is not shown until the wet and dry patterns are separated. Notably, the correlations differ between these two patterns, with icing rate being negatively correlated with temperature for the wet growth process, but positively correlated with wind speed and liquid water content for the dry growth process. Third, both wet and dry growth processes exist across the icing events. A shift from wet to dry growth was evident with increasing altitude. At the mountain's base, wet growth predominates, with the icing rate determined by the temperature close to the freezing point, whereas the higher temperature and lower liquid water flux account for the shorter wire icing duration, lower icing rate, and thus the thinner icing thickness at the leeward slope compared to the windward slope at a similar altitude. This study sheds light on the variations in icing rates under different micro-topographies and the underlying physical mechanisms governing icing growth patterns and provides a much-needed understanding of these distinct growth processes on the development of a more sophisticated predictive model for conductor icing. [ABSTRACT FROM AUTHOR]

In order to detect abnormal heat generation in time, a reversible color-changing coating temperature measurement method is proposed for self-detection of temperature by power equipment, and its adhesion characteristics and aging performance were analyzed. The results showed that the reversible color-changing coating prepared with crystalline violet lactone as the colorant, bisphenol A as the color developer, octadecanol as the solvent, and RTV-II as the base paint can meet the requirements of self-detection of temperature by power equipment with its adhesion performance. The accelerated aging tests using high temperature, light and humidity were carried out in the laboratory, and we concluded that the deterioration degree of the color-changing coating was positively correlated with the temperature. Light can accelerate the aging rate of reversible color-changing coatings, and the degradation process of the coating was significantly accelerated under UV light. The effect of humidity on the coating was not significant. The degradation of the coating after aging for 288 h under indoor conditions was small, while it was accelerated under outdoor natural conditions. This research can provide a reference for the on-site application of reversible color-changing coatings for self-detection of temperature by power equipment. [ABSTRACT FROM AUTHOR]

Anti-inflammatory drugs have become the second-largest class of common drugs after anti-infective drugs in animal clinical care worldwide and are often combined with other drugs to treat fever and viral diseases caused by various factors. In our previous study, a novel serine protease inhibitor-encoding gene (MDSPI16) with improved anti-inflammatory activity was selected from a constructed suppressive subducted hybridization library of housefly larvae. This protein could easily induce an immune response in animals and had a short half-life, which limited its wide application in the clinic. Thus, in this study, mPEG-succinimidyl propionate (mPEG-SPA, Mw = 5 kDa) was used to molecularly modify the MDSPI16 protein, and the modified product mPEG-SPA-MDSPI16, which strongly inhibited elastase production, was purified. It had good stability and safety, low immunogenicity, and a long half-life, and the IC50 for elastase was 86 nM. mPEG-SPA-MDSPI16 effectively inhibited the expression of neutrophil elastase and decreased ROS levels. Moreover, mPEG-SPA-MDSPI16 exerted anti-inflammatory effects by inhibiting activation of the NF-κB signaling pathway and the MAPK signaling pathway in neutrophils. It also exerted therapeutic effects on a lipopolysaccharide (LPS)-induced acute lung injury (ALI) mouse model. In summary, mPEG-SPA-MDSPI16 is a novel anti-inflammatory protein modified with PEG that has the advantages of safety, nontoxicity, improved stability, and strong anti-inflammatory activity in vivo and in vitro and is expected to become an effective anti-inflammatory drug. [ABSTRACT FROM AUTHOR]

The emergence of multi-drug-resistant (MDR) pathogens has considerably challenged the development of new drugs. Probiotics that inhibit MDR pathogens offer advantages over chemical antibiotics and drugs due to their increased safety and fewer side effects. This study reported that Weissella cibaria P-8 isolated from pickles showed excellent antibacterial activity against intestinal pathogens, particularly the antibacterial activity against MDR Escherichia coli B2 was the highest. This study showed that the survival rates of W. cibaria P-8 at pH 2.0 and 0.3% bile salt concentration were 72% and 71.56%, respectively, and it still had antibacterial activity under pepsin, trypsin, protease K, and catalase hydrolysis. Moreover, W. cibaria P-8 inhibits the expression of inflammatory factors interleukin-1β, tumor necrosis factor-α, and interleukin-6, upregulates the interleukin-10 level, and increases total antioxidant capacity and superoxide dismutase enzyme activity in serum. W. cibaria P-8 also efficiently repairs intestinal damage caused by E. coli infection. The gut microbiota analysis demonstrated that W. cibaria P-8 colonizes the intestine and increases the abundance of some beneficial intestinal microorganisms, particularly Prevotella. In conclusion, W. cibaria P-8 alleviated MDR E. coli-induced intestinal inflammation by regulating inflammatory cytokine and enzyme activity and rebalancing the gut microbiota, which could provide the foundation for subsequent clinical analyses and probiotic product development. [ABSTRACT FROM AUTHOR]

Expansins (EXPs) loosen plant cell walls and are involved in diverse developmental processes through modifying cell-walls; however, little is known about the role of PpEXPs in peach fruit. In this study, 26 PpEXP genes were identified in the peach genome and grouped into four subfamilies, with 20 PpEXPAs, three PpEXPBs, one PpEXPLA and two PpEXPLBs. The 26 PpEXPs were mapped on eight chromosomes. The primary mode of gene duplication of the PpEXPs was dispersed gene duplication (DSD, 50%). Notably, cis-elements involved in light responsiveness and MeJA-responsiveness were detected in the promoter regions of all PpEXPs, while ethylene responsive elements were observed in 12 PpEXPs. Transcript profiling of PpEXPs in the peach fruit varieties of MF (melting), NMF (non-melting) and SH (stony hard) at different stages showed that PpEXPs displayed distinct expression patterns. Among the 26 PpEXPs, 15 PpEXPs were expressed in the fruit. Combining the expressing patterns of PpEXPs in fruits with different flesh textures, PpEXPA7, PpEXPA13 and PpEXPA15 were selected as candidate genes, as they were highly consistent with the patterns of previous reported key genes (PpPGM, PpPGF and PpYUC11) in regard to peach fruit texture. The genes with different expression patterns between MF and NMF were divided into 16 modules, of which one module, with pink and midnightblue, negatively correlated with the phenotype of fruit firmness and was identified as PpEXPA1 and PpEXPA7, while the other module was identified as PpERF in the pink module, which might potentially effect fruit texture development by regulating PpEXPs. These results provide a foundation for the functional characterization of PpEXPs in peach. [ABSTRACT FROM AUTHOR]

One-time fertilization with controlled-release urea (CRU) is a research hotspot for its lower labor cost and stability of nitrogen (N) supply for rice growth. Yet the fertilizer formulation needs to be further improved to better adjust the N supplement to meet the demand of rice plants and obtain a higher grain yield. Therefore, the effects of novel fertilizer formulations composed of CRU, urease inhibitor (UI) and nitrification inhibitor (NI) on the rice growth and photosynthetic characteristics as well as high-yield formation were tested through a two-year field experiment. The result indicated that the combined use of CRU and UI treatment can achieve higher yields than with CRU at the same N application level. Meanwhile, with a 20% reduction of N use, one-time application of CRU + UI can obtain the same high yield as the conventional split application of urea. Compared with conventional fertilization and CRU treatment, the CRU + UI treatment had suitable leaf area and biomass accumulation at the vegetative growth stage and high effective stem tiller rate. More post-anthesis dry matter accumulation, higher net photosynthesis rate and low senescence rate were guaranteed for its high yield and nitrogen agronomic efficiency. [ABSTRACT FROM AUTHOR]

The surface–tension-driven coalescence of drops has been extensively studied because of the omnipresence of the phenomenon and its significance in various natural and engineering systems. When two drops come into contact, a liquid bridge is formed between them and then grows in its lateral dimensions. As a result, the two drops merge to become a bigger drop. The growth dynamics of the bridge are governed by a balance between the driving force and the viscous and inertial resistances of involved liquids, and it is usually represented by power–law scaling relations on the temporal evolution of the bridge dimension. Such scaling laws have been well-characterized for the coalescence of unconfined or freely suspended drops. However, drops are often confined by solid or liquid surfaces and thus are a different shape from spheres, which affects their coalescence dynamics. As such, the coalescence of confined drops poses more complicated interfacial fluid dynamics challenges compared to that of unconfined drops. Although there have been several studies on the coalescence of confined drops, they have not been systematically reviewed in terms of the properties and geometry of the confining surface. Thus, we aim to review the current literature on the coalescence of confined drops in three categories: drop coalescence on a solid surface, drop coalescence on a deformable surface, and drop coalescence between two parallel surfaces with a small gap (i.e., Hele-Shaw cell), with a focus on power–law scaling relations, and to suggest challenges and outlooks for future research on the phenomena. [ABSTRACT FROM AUTHOR]

Zinc deficiency in rice can lead to reduced nutritional value and taste. This study investigates the potential of zinc oxide nanoparticles (ZnO NPs) as a foliar fertilizer during the jointing stage to improve rice yield, quality, and grain zinc enrichment. Over a two-year field experiment (2019–2020), six doses of ZnO NPs (ranging from 0 to 12 kg hm−2) were applied during the jointing stage (46 days after transplanting). The results revealed that foliar spraying of ZnO NPs increased the number of spikelets per spike and the thousand-grain weight by 7.4% to 9.2% and 4.2% to 7.1%, respectively, resulting in a substantial increase in rice yield. Furthermore, it led to a reduction in chalky white and chalky whiteness by 6.23% to 23.6% and 2.2% to 27.9%. ZnO NPs effectively boosted zinc content in rice grains while decreasing the phytic acid to zinc ratio, indicating improved zinc enrichment. Remarkably, protein and amylose content remained unaffected. These findings underscore the potential of ZnO NPs as a foliar fertilizer to enhance rice production, quality, and zinc enrichment. Further research can explore optimal application strategies and long-term effects for sustainable rice production. [ABSTRACT FROM AUTHOR]

Polyethylene oxide (PEO)-based composite polymer electrolytes (CPEs) containing in situ SiO2 fillers are prepared using an electrostatic spinning method at room temperature. Through the in situ hydrolysis of tetraethyl silicate (TEOS), the generated SiO2 nanospheres are uniformly dispersed in the PEO matrix to form a 3D ceramic network, which enhances the mechanical properties of the electrolyte as a reinforcing phase. The interaction between SiO2 nanospheres and PEO chains results in chemical bonding with a decrease in the crystallinity of the PEO matrix, as well as the complexation strength of PEO chains with lithium ions during the hydrolysis process. Meanwhile, the addition of SiO2 nanospheres can disturb the orderliness of PEO chain segments and further suppress the crystallization of the PEO matrix. Therefore, improved mechanical/electrochemical properties can be obtained in the as-spun electrolyte with the unique one-dimensional high-speed ion channels. The electrospun CPE with in situ SiO2 (10 wt%, ca. 45 nm) has a higher ionic conductivity of 1.03 × 10−3 S cm−1 than that of the mechanical blending one. Meanwhile, the upper limit of the electrochemical stability window is up to 5.5 V versus Li+/Li, and a lithium-ion migration number can be of up to 0.282 at room temperature. In addition, in situ SiO2 electrospun CPE achieves a tensile strength of 1.12 MPa, elongation at the break of 488.1%, and it has an excellent plasticity. All in all, it is expected that the electrospun CPE prepared in this study is a promising one for application in an all-solid-state lithium-ion battery (LIB) with a high energy density, long life cycle, and high safety. [ABSTRACT FROM AUTHOR]

The behavioral intention of tourists to protect the environment is a popular topic in tourism geography research. Understanding the mechanisms that influence the post-tour behavioral intentions of heritage site visitors can effectively promote the generation of positive behavioral intentions for the sustainable development of heritage sites. Starting from the "cognitive–emotional–behavioral" path of attitude theory, we introduced environmental knowledge awareness (EKA), geomorphological value perception (GVP), place attachment (PA) and behavioral intention (BI) variables to construct a model of the influence mechanism of tourists' behavioral intentions towards conservation in heritage sites; we test this model on the Libo World Natural Heritage Site, a karst in southern China, as an example. The results show the following: (1) environmental knowledge awareness (EKA) is the basis of place attachment (PA) and behavioral intention (BI), and place attachment (PA) plays an influential mediating role. (2) Geomorphological value perception (GVP) has a positive effect on behavioral intention. (3) The "GEPB" conceptual model fits the "cognitive–emotional response–behavioral intention" chain of tourists in natural world heritage sites and passes the empirical test; (4) The direct positive effect of place attachment on behavioral intention is significant as an essential emotional factor that promotes behavioral intention. This study provides an empirical foundation for the synergistic development of conservation and tourism in World Heritage Karst Sites. It also discusses theoretical and managerial implications based on the findings and provides directions for future research. [ABSTRACT FROM AUTHOR]

An extensive experimental database consisting of 2838 shrinkage data points and 3598 creep data points is used to evaluate the accuracy of the newly proposed CEB-FIP 2010 model in predicting the creep and shrinkage of concrete structures. To study the applicability of the model for high-strength concrete in general environments, the database was developed by only retaining the test data of concrete components with the average compressive strength greater than 30 MPa and the relative humidity in the test environment less than 95%. On this basis, combined with the B3 and CEB variation coefficient methods, the paper mainly adopts the residual method to assess the accuracy of the CEB-FIP 2010 model and compare it with the previous model, CEB-FIP 1990. The influences of several properties, such as the compressive strength, the age of concrete, the relative humidity, and the component size on the prediction accuracy of these two models are further studied. The results show that for the CEB-FIP 2010 model within the time interval of 0–9000 days, 52% and 48% of the shrinkage strain residuals of the total specimens are located in the negative and positive regions, respectively, while the positive and negative regions of the CEB-FIP 1990 model account for 73% and 27%, demonstrating the CEB-FIP 2010 model has better performance in predicting shrinkage strain than the CEB-FIP 1990 model, whereas the two models have comparable accuracy in predicting creep compliance. The CEB-FIP 2010 model is more reliable for considering the effects of compressive strength, relative humidity, and age at loading on shrinkage and creep than for considering the effect of member size. [ABSTRACT FROM AUTHOR]

In this study, we proposed a novel Ru(bpy)32+-Au-WS2 nanocomposite (Ru-Au-WS2 NCs) nano-hybrid electrochemiluminescence (ECL) probe for the highly sensitive detection of carcinoembryonic antigen (CEA). This system utilizes Au nanoparticles (Au NPs) as a bridge to graft the high-performance of a Ru(bpy)32+ ECL emitter and WS2 nanosheet with excellent electrochemical performance into an ECL platform, which shows outstanding anodic ECL performance and biosensing platform due to the synergetic effect and biocompatibility of Au NPs and WS2 nanosheet. Because the ECL intensity of Ru(bpy)32+ is sensitively affected by the antibody-antigen insulator, a preferable linear dependence was obtained in the concentration range of CEA from 1 pg·mL−1 to 350 ng·mL−1 with high selectivity (LOD of 0.3 pg·mL−1, S/N = 3). Moreover, the ECL platform had good reproducibility and stability and exhibited excellent anti-interference performance in the detection process of CEA. We believe that the platform we have developed can expand the opportunities for the detection of additional high specificity-related antibodies/antigens and demonstrate broad prospects for disease diagnosis and biochemical research. [ABSTRACT FROM AUTHOR]

The heat shock protein 20 (HSP20) proteins comprise an ancient, diverse, and crucial family of proteins that exists in all organisms. As a family, the HSP20s play an obvious role in thermotolerance, but little is known about their molecular functions in addition to heat acclimation. In this study, 42 PpHSP20 genes were detected in the peach genome and were randomly distributed onto the eight chromosomes. The primary modes of gene duplication of the PpHSP20s were dispersed gene duplication (DSD) and tandem duplication (TD). PpHSP20s in the same class shared similar motifs. Based on phylogenetic analysis of HSP20s in peach, Arabidopsis thaliana, Glycine max, and Oryza sativa, the PpHSP20s were classified into 11 subclasses, except for two unclassified PpHSP20s. cis-elements related to stress and hormone responses were detected in the promoter regions of most PpHSP20s. Gene expression analysis of 42 PpHSP20 genes revealed that the expression pattern of PpHSP20-32 was highly consistent with shoot length changes in the cultivar 'Zhongyoutao 14', which is a temperature-sensitive semi-dwarf. PpHSP20-32 was selected for further functional analysis. The plant heights of three transgenic Arabidopsis lines overexpressing PpHSP20-32 were significantly higher than WT, although there was no significant difference in the number of nodes. In addition, the seeds of three over-expressing lines of PpHSP20-32 treated with high temperature showed enhanced thermotolerance. These results provide a foundation for the functional characterization of PpHSP20 genes and their potential use in the growth and development of peach. [ABSTRACT FROM AUTHOR]

One-time fertilization with controlled-released fertilizer (CRF) is a promising way for reducing labor cost, increasing nitrogen use efficiency (NUE) and alleviating environmental pollution in winter wheat (Triticum aestivum L.) cultivation. However, CRF release characteristics are related to various factors such as soil properties, temperature and precipitation, and further study is needed in developing suitable fertilizer formulas adapting to local conditions. In this study, five types of CRF were used for a one-time application in a two-year field experiment conducted at two sites with two wheat cultivars. Their effects on soil inorganic nitrogen (SIN) content, nitrogen uptake, wheat growth and grain yield were investigated. The results indicated that nitrogen supply in the CRF-60/80 treatments not only ensured the tiller differentiation at the early growth stage, but also provided adequate SIN after the jointing stage, thereby facilitating the dry matter accumulation and improving post-anthesis photosynthates accumulating in grains. When compared with conventional split fertilization, the CRF-60 and 80 treatments improved the NUE by 9.7–12.1%, and boosted farmers' economic efficiency by 282.4–327.2 CNY ha−1. According to our research, a one-time application of CRF-60 and CRF-80 could meet the needs of the two-peak nitrogen demand of wheat in Jiangyan and Yanghzou respectively, therefore increasing NUE and having low labor costs for wheat fertilizer application. [ABSTRACT FROM AUTHOR]

Knowing the meniscus shape of confined drops is important for understanding how they make first contact and then coalesce. When imaged from the top view by brightfield microscopy, a liquid drop (e.g., corn syrup) confined in a Hele-Shaw cell, surrounded by immiscible liquid (e.g., mineral oil), had a dark annulus, and the width of the annulus decreased with increasing concentration of corn syrup. Since the difference in the annulus width was presumed to be related to the meniscus shape of the drops, three-dimensional images of the drops with different concentrations were obtained using confocal fluorescence microscopy, and their cross-sectional meniscus profile was determined by image processing. The meniscus of the drops remained circular despite varying concentration. Since the refractive index of corn syrup increased with concentration, while the surface tension coefficient between corn syrup and mineral oil remained unchanged, the observed change in the annulus width was then attributed to the refraction of light passing through the drop's meniscus. As such, a ray optics model was developed, which predicted that the annulus width of the drop would decrease as the refractive index of the drop approached that of the surrounding liquid. Therefore, the dark annulus of the drops in the Hele-Shaw cell was caused by the refraction of light passing through the circular meniscus of the drop. [ABSTRACT FROM AUTHOR]

Cereal trade is essential for economic and commercial cooperation among countries along the "Belt and Road" (BRI). It helps ensure food security and contributes to building a community of interests and destinies for the BRI countries. Based on the UN Comtrade database, this study, using a network analysis approach, investigates the structural characteristics and spatiotemporal dynamics of cereal trade networks among the "Belt and Road" countries. Results show that: (1) The cereal trade among the BRI countries has formed well-connected and complex trade networks, and the "Belt and Road" initiative has significantly promoted cereal trade networks among the BRI countries. (2) The backbone structures of cereal trade networks along the BRI are in geographical proximity. India, Russia, and Ukraine are the most important trading partners and absolute core nodes in the trade networks, influencing the entire cereal trade networks. (3) The BRI cereal trade networks exhibit significant core-periphery structures, with considerable power asymmetries between the countries reflecting food supply and demand differences. In general, the BRI cereal trade networks have developed from relatively diversified to polarized. Supply chains in the cereal trade network are dominated by a few large countries and are fragile, with weak resilience and low resistance to risk. Therefore, governments should continue to strengthen regional cooperation, optimize cereal trade network structure, enhance their reserve capacity, and build a stronger system to guarantee food security and prevent risk. All these measures will support the food security of the "Belt and Road" countries. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to reveal the spatiotemporal evolution of entrepreneurial activities in the local municipalities of the Yangtze River Delta at long timescales from a geographic perspective and to reveal the underlying factors driving such evolution. The ontology of entrepreneurial activities—startups—was chosen as the object of this study, and the developmental characteristics of entrepreneurial activities in the region since 2001 were explored in two dimensions: time series changes and spatial evolution. The driving mechanism was further explored using the geographical detector. The results showed that: (1) Intensive entrepreneurial activities have been underway in the Yangtze River Delta since the beginning of the 21st century. The entrepreneurial process has undergone a stable period of slow growth (2001–2013), as well as one of rapid growth (2014–2018). The number of startups increased during this period, from 241,700 in 2001 to 1,959,600 in 2018. (2) The density of entrepreneurial activities in the Yangtze River Delta has increased since 2001. The agglomerative patterns showed developmental trends of both concentration and diffusion, forming a dotted pattern of agglomeration centered on the provincial capitals of Nanjing, Hangzhou, and Hefei and a belt of agglomeration centered on Shanghai-Suzhou-Wuxi-Changzhou. (3) High-value agglomeration of entrepreneurial activities was found to be relatively stable, and low-value agglomeration steadily weakened. Shanghai, Suzhou, and Nantong have long been part of H-H clusters, while Chizhou, Wuhu, Bozhou, Huaibei, and Huainan in Anhui have become areas of depressed entrepreneurial activities. (4) Financial strength, degree of informationization, economic foundation, innovative vitality, openness, and market demand are the main factors affecting entrepreneurial activities in the Yangtze River Delta. Entrepreneurial activities have significant spatial correlation, and areas with high entrepreneurial vitality radiate their effect to the entrepreneurial activities in the surrounding areas. The factors affecting entrepreneurial activities have multiple characteristics, and policy makers should promote entrepreneurial activities with a comprehensive vision and multi-channel efforts. The findings of this study add to the understanding of the spatial proximity characteristics of long time series of entrepreneurial activities at the municipal scale in developing countries and reveal the characteristics of the multi-factor combinations affecting them. [ABSTRACT FROM AUTHOR]

Zinc oxide nanoparticles (ZnO NPs) have been applied widely in agriculture, and many studies were conducted to evaluate the effect of ZnO NPs on plant growth. So far, few studies have been investigated with regard to the potential effect of ZnO NPs on cereal yield formation or Zn content in grains. Herein, we used a pot experiment, which was conducted involving five dosages of Zn (0.3, 0.6, 1.2, 2.4, and 4.8 g Zn pot−1), to evaluate the impacts which ZnO NPs made in rice yield, dry matter accumulation, rice quality and grain Zn contents. The results demonstrated that ZnO NPs increased the production of grain, dry matter accumulation and particulate Zn content. Compared with control treatment, ZnO NPs application presented higher rice yield with more panicle number (4.83–13.14%), spikelets per panicle (4.81–10.69%), 1000-grain weight (3.82–6.62%) and filled grain rate (0.28–2.36%). Additionally, the dry jointing, heading and mature periods, LAI, SPAD values, and photosynthetic potentials of ZnO NPs were all significantly higher relative to treatment without ZnO NPs. The more photosynthetic substances and higher dry matter accumulated in the whole rice growing stage resulted in higher rice grain yield. Furthermore, ZnO NPs increased brown rice rate, milled rice rate, head rice rate, chalkiness size, chalkiness grain rate, chalkiness degree, amylose content and protein content, improving rice processing and appearance qualities. For the Zn nutrition in rice grain, ZnO NPs application significantly increased the Zn content of edible polished rice and promoted the relocation of Zn from the aleurone layer. This study effectively demonstrated that ZnO NPs could be a potential high-performed fertiliser for enhancing rice yield and quality. [ABSTRACT FROM AUTHOR]

The poor stability of antibacterial peptide to protease limits its clinical application. Among these limitations, trypsin mainly exists in digestive tract, which is an insurmountable obstacle to orally delivered peptides. OM19R is a random curly polyproline cationic antimicrobial peptide, which has high antibacterial activity against some gram-negative bacteria, but its stability against pancreatin is poor. According to the structure-activity relationship of OM19R, all cationic amino acid residues (l-arginine and l-lysine) at the trypsin cleavage sites were replaced with corresponding d-amino acid residues to obtain the designed peptide OM19D, which not only maintained its antibacterial activity but also enhanced the stability of trypsin. Proceeding high concentrations of trypsin and long-time (such as 10 mg/mL, 8 h) treatment, it still had high antibacterial activity (MIC = 16–32 µg/mL). In addition, OM19D also showed high stability to serum, plasma and other environmental factors. It is similar to its parent peptide in secondary structure and mechanism of action. Therefore, this strategy is beneficial to improve the protease stability of antibacterial peptides. [ABSTRACT FROM AUTHOR]

ZnO, as an important semiconductor material, has attracted much attention due to its excellent physical properties, which can be widely used in many fields. Notably, the defects concentration and type greatly affect the intrinsic properties of ZnO. Thus, controllable adjustment of ZnO defects is particularly important for studying its photoelectric properties. In this work, we fabricated ZnO ceramics (ZnO(C)) with different defects through spark plasma sintering (SPS) process by varying sintering temperature and using reduction environment. The experimental results indicate that the changes of color and light absorption in as-prepared ZnO originate from the different kinds of defects, i.e., oxygen vacancies (VO), interstitial zinc (Zni), and Zinc vacancies (VZn). Moreover, with the increase in calcination temperature, the concentration of oxygen defects and interstitial zinc defects in the ceramics increases gradually, and the conductivity of the ceramics is also improved. However, too many defects are harmful to the photoelectrochemical properties of the ceramics, and the appropriate oxygen defects can improve the utilization of visible light. [ABSTRACT FROM AUTHOR]

Metabolites play vital roles in shaping the quality of fresh fruit. In this study, Korla pear fruit harvested from twelve orchards in South Xinjiang, China, were ranked in sensory quality by fuzzy logic sensory evaluation for two consecutive seasons. Then, gas chromatography-mass spectrometry (GC-MS) was applied to determine the primary metabolites and volatile compounds. Sensory evaluation results showed that the panelists were more concerned about 'mouth feel' and 'aroma' than about 'fruit size', 'fruit shape' and 'peel color'. In total, 20 primary metabolites and 100 volatiles were detected in the pear fruit. Hexanal, (E)-2-hexenal, nonanal, d-limonene, (Z)-3-hexen-1-yl acetate and hexyl acetate were identified as the major volatile compounds. Correlation analysis revealed that l-(+)-tartaric acid, hexanoic acid, trans-limonene oxide and 2,2,4-trimethyl-1,3-pentanediol diisobutyrate were negatively correlated with sensory scores. Furthermore, OPLS-DA results indicated that the fruit from three orchards with lower ranks in quality could be distinguished from other samples based on the contents of l-(+)-tartaric acid and other eight metabolites, which were all associated with 'mouth feel' and 'aroma'. This study reveals the metabolites that might be closely associated with the sensory quality attributes of Korla pear, which may provide some clues for promoting the fruit quality in actual production. [ABSTRACT FROM AUTHOR]

The aroma quality of citrus fruit is determined by volatile compounds, which bring about different notes to allow discrimination among different citrus species. However, the volatiles with various aromatic traits specific to different citrus species have not been identified. In this study, volatile profiles in the fruit peels of four citrus species collected from our previous studies were subjected to various analyses to mine volatile biomarkers. Principal component analysis results indicated that different citrus species could almost completely be separated. Thirty volatiles were identified as potential biomarkers in discriminating loose-skin mandarin, sweet orange, pomelo, and lemon, while 17 were identified as effective biomarkers in discriminating clementine mandarins from the other loose-skin mandarins and sweet oranges. Finally, 30 citrus germplasms were used to verify the classification based on β-elemene, valencene, nootkatone, and limettin as biomarkers. The accuracy values were 90.0%, 96.7%, 96.7%, and 100%, respectively. This research may provide a novel and effective alternative approach to identifying citrus genetic resources. [ABSTRACT FROM AUTHOR]

Tin oxide quantum dots were synthesized in aqueous solution via a simple hydrolysis and oxidation process. The morphology observation showed that the quantum dots had an average grain size of 2.23 nm. The rutile phase SnO2 was confirmed by the structural and compositional characterization. The fluorescence spectroscopy of quantum dots was used to detect the heavy metal ions of Cd2+, Fe3+, Ni2+ and Pb2+, which caused the quenching effect of photoluminescence. The quantum dots showed the response of 2.48 to 100 ppm Ni2+. The prepared SnO2 quantum dots exhibited prospective in the detection of heavy metal ions in contaminated water, including deionized water, deionized water with Fe3+, reclaimed water and sea water. The limit of detection was as low as 0.01 ppm for Ni2+ detection. The first principle calculation based on the density function theory demonstrated the dependence of fluorescence response on the adsorption energy of heavy metal ions as well as ion radius. The mechanism of fluorescence response was discussed based on the interaction between Sn vacancies and Ni2+ ions. A linear correlation of fluorescence emission intensity against Ni2+ concentration was obtained in the logarithmic coordinates. The density of active Sn vacancies was the crucial factor that determined fluorescence response of SnO2 QDs to heavy metal ions. [ABSTRACT FROM AUTHOR]

Due to the unbalanced three-phase loads, the single-phase distributed photovoltaic (PV) integration, the long feeders, and the heavy loads in a three-phase four-wire low voltage distribution network (LVDN), the voltage unbalance factor (VUF), the network loss and the voltage deviation are relatively high. Considering the uncertain fluctuation of the PV output and the load power, a robust optimal allocation of decentralized reactive power compensation (RPC) devices model for a three-phase four-wire LVDN is proposed. In this model, the uncertain variables are described as box uncertain sets, the three-phase simultaneous switching capacity and single-phase independent switching capacity of the RPC devices are taken as decision variables, and the objective is to minimize the total power loss of the LVDN under the extreme scenarios of uncertain variables. The bi-level optimization method is used to transform the robust optimization model with uncertain variables into bi-level deterministic optimization models, which could be solved alternately. The nonlinear programming solver IPOPT in the mature commercial software GAMS is adopted to solve the upper and lower deterministic optimization models to obtain a robust optimal allocation scheme of decentralized RPC devices. Finally, the simulation results for an actual LVDN show that the obtained decentralized RPC scheme can ensure that the voltage deviation and the VUF of each bus satisfied the secure operation requirement no matter how the PV output and load power changed within their own uncertain sets, and the network loss could be effectively reduced. [ABSTRACT FROM AUTHOR]

The antimicrobial peptide LR GG (LLRLLRRGGRRLLRLL-NH2) was designed and chemically synthesized in a study conducted by Jia et al. Gram-negative bacteria were found to be sensitive to LR GG and exhibited a high therapeutic index. Genetic engineering methods were used to create the prokaryotic fusion expression vector pQE-GFP-LR GG , and the resulting corresponding fusion protein GFP-LR GG was subsequently expressed and purified. The precursor GFP was then removed by TEV proteolysis, and pure LR GG was obtained after another round of purification and endotoxin removal. The prokaryotic-expressed antimicrobial peptide LR GG displays a broad-spectrum antibacterial effect on Gram-negative bacteria, and its minimum inhibitory activity (MIC) against Escherichia coli can reach 2 μg/mL. Compared to the chemically synthesized LR GG, the prokaryotic-expressed LR GG exhibits similar temperature, pH, salt ion, serum stability, and cell selectivity. Furthermore, prokaryotic-expressed LR GG showed excellent therapeutic effects in both the infection model of cell selectivity and no embryotoxicity in a Galleria mellonella infection model. The mechanism by which LR GG causes bacterial death was found to be the disruption of the Gram-negative cell membrane.

Apoptosis and necrosis of intestinal epithelial cells (IECs), induced by ischemia-reperfusion (I/R) injury, can lead to dysfunction of the intestinal barrier, which could cause multiple organ dysfunction syndromes. Mesenchymal stem cells (MSCs) have the potential of providing protective effects on damaged IECs via paracrine action. This study investigated whether hypoxia can enhance the protective effect of placental-derived MSCs (pMSCs) on H2O2-treated-caco2 cells, and explored the possible mechanism. The pMSCs isolated by tissue culture were fibroblast-like, positive for CD73, CD90 and CD105 and can differentiate into chondrocytes and endothelial cells. Five days after treatment with H2O2, the numbers of living caco2 cells significantly decreased. More live H2O2-treated-caco2 cells were observed in pMSCs hypoxia culture medium (pMSCs-HCM) than pMSCs normoxia culture medium (pMSCs-NCM), and the application of a specific antibody that blocked insulin-like growth factor-1 (IGF-1) leads to a significant decrease of the protective effect of pMSCs-HCM. Hypoxia can promote IGF-1 expression of pMSCs at mRNA and protein levels, and caco2 stably expressed IGF-1 receptor. Knocking down IGF-1 expression in pMSCs by siRNA resulted in a significant attenuation of the increase in apoptosis of H2O2-treated-caco2 cultured in pMSCs-HCM. In conclusion, hypoxia can increase the protective effect of pMSCs on H2O2-treated-caco2 cells via a promotion of their paracrine actions, and the key cytokine involved is IGF-1.