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Climate warming and high-intensity human activities threaten the stability of alpine meadow ecosystems. The stability of the soil microbial community is crucial for maintaining ecological service function. However, the effects of warming and litter removal on microbial interactions, community-building processes, and species coexistence strategies remain unclear. In this study, we used a fiberglass open-top chamber to simulate global change, and moderate grazing in winter was simulated by removing above-ground litter from all plants in the Qinghai–Tibet Plateau, China, to investigate the effects of warming, litter removal, and interactions on soil microbial communities. The treatments included (1) warming treatment (W); (2) litter removal treatment (L); (3) the combined treatment (WL); and (4) control (CK). The results show that compared with the control treatment, warming, litter removal, and the combined treatments increased bacterial Shannon diversity but reduced fungal Shannon diversity, and warming treatment significantly changed the bacterial community composition. Warming, litter removal, and the combined treatments reduced the colinear network connectivity among microorganisms but increased the modularity of the network, and the average path distance and average clustering coefficient were higher than those in the control group. Stochastic processes played a more important role in shaping the microbial community composition, and soil–available phosphorus and soil ammonium contributed more to the βNTI of the bacterial community, while total phosphorus and NAG enzyme in the soil contributed more to the βNTI of the fungal community. Notably, litter removal counteracts the effects of warming on bacterial communities. These results suggest that litter removal may enhance bacterial community stability under warming conditions, providing insights for managing alpine meadow ecosystems in the context of climate change.

ABSTRACTEffective control of gene expression is crucial for understanding gene function in both eukaryotic and prokaryotic cells. While several inducible gene expression systems have been reported in Streptococcus mutans, a conditional pathogen that causes dental caries, the significant non-inducible basal expression in these systems seriously limits their utility, especially when studying lethal gene functions and molecular mechanisms. We introduce a tightly controlled xylose-inducible gene expression system, TC-Xyl, for Streptococcus mutans. Western blot results and fluorescence microscopy analysis indicate that TC-Xyl exhibits an extremely low non-inducible basal expression level and a sufficiently high expression level post-induction. Further, by constructing a mutation in which the only source FtsZ is under the control of TC-Xyl, we preliminarily explored the function of the ftsz gene. We found that FtsZ depletion is lethal to Streptococcus mutans, resulting in abnormal round cell shape and mini cell formation, suggesting FtsZ’s role in maintaining cell shape stability.

Objective: To explore the lipid-lowering effect of compound seabuckthorn concentrate in hyperlipidemia model rats. Methods: Sixty Wistar rats were randomly divided into blank-control group, high-fat diet group, positive control group (lovastatin capsules 1.80 mg/kg·bw), compound seabuckthorn concentrate low (3.57 mL/kg·bw), medium (7.14 mL/kg·bw), high (14.28 mL/kg·bw) dose groups. The hyperlipidemia rat models were established by feeding high-fat diet. The blank-control group and the high-fat diet group were given the same amount of normal saline by gavage, and the rats of experimental groups were given the corresponding dose of compound seabuckthorn concentrate and lovastatin suspension by gavage, respectively. After 28 days of administration, the body weight, Lee's index, serum lipid level, antioxidant level, liver index and liver pathological morphology of rats in each group were observed and analyzed. Results: Compared with the blank-control group, the body weight and Lee's index of the high-fat diet group were significantly increased (P

Objective: In order to expand the research of functional products, the content of active ingredients in Pueraria thomsonii was increased by microbial fermentation technology. Methods: Firstly, the fermentation process of Pueraria thomsonii was optimized by the combination of single factor test and response surface methodology with the decoction pieces of Pueraria thomsonii as raw material, L. acidophilus as fermentation strain, puerarin content as index, and inoculation amount, solid-liquid ratio, fermentation time and fermentation temperature as acting factors. Secondly, the contents of puerarin, daidzin, daidzein, total isoflavones, soluble polysaccharides and total starch in Pueraria thomsonii were determined by high performance liquid chromatography, ultraviolet spectrophotometry and dual wavelength method before and after fermentation. Results: The optimal fermentation conditions were as follows: Inoculation amount 5%, solid-liquid ratio 1:3 g/mL, fermentation time 36 h, fermentation temperature 29 ℃. The relative error was 0.29% between the actual content 8.1854 mg/g and predicted value 8.2092 mg/g of puerarin. After fermentation, the contents of puerarin, daidzin, daidzein, total isoflavones, soluble polysaccharides and amylopectin in Pueraria thomsonii increased, while the contents of amylose and total starch decreased, showing significant differences compared with those before fermentation (P

Objective: To investigate the relative content of polyunsaturated fatty acids (PUFAs) in Portulaca oleracea and the effect of Portulaca oleracea purified oil on lipid accumulation in HepG2 cells. Methods: The fatty acid composition of whole herb oil and purified oil were analyzed by gas chromatography-mass spectrometry. MTT method was used to determine the effect of different concentrations of Portulaca oleracea purified oil on cell viability and the suitable concentration range was selected for subsequent experiments. Oil red O staining was used to determine whether the oleic acid-induced lipid accumulation model was successfully established. The kit method was used to determine the effects of purified oil concentration on high density lipoprotein-cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C), total cholesterol (TC) and triglyceride (TG) levels in low, medium and high dose groups (60、80、100 μg/mL). Results: There were three kinds of PUFAs in Portulaca oleracea include linoleic acid, α-linolenic acid and γ-linolenic acid. The relative content of PUFAs in the whole herb oil of Portulaca oleracea was 27.6104%, and the relative content of purified oil after enrichment and purification was as high as 73.9015%. The concentration range of purified oil selected by MTT method was 60~100 μg/mL. Compared with the model group, the concentration of HDL-C in the high-dose group (100 μg/mL) of Portulaca oleracea purified oil was significantly increased, and the concentrations of LDL-C, TC and TG were significantly decreased (P

With the era of the internet of things (IoT), the protocol stack conversion scheme based on the application-layer’s gateway has problems such as poor performance and end to end security that can’t be guaranteed.A lightweight and trusted IoT IP communication protocol was proposed, which was the main research direction of Protocol and Interface Group in Network 5.0 Industry and Technology Innovation Alliance, the deployment costs of protocol conversion gateways was decreased, the computing and storage overhead of IoT devices was reduced, and end to end communication security was ensured.

OTUD6A is a deubiquitinase that plays crucial roles in various human diseases. However, the precise regulatory mechanism of OTUD6A remains unclear. In this study, we found that OTUD6A significantly inhibited the production of type I interferon. Consistently, peritoneal macrophages and bone marrow-derived macrophages from Otud6a−/− mice produced more type I interferon after virus infection compared to cells from WT mice. Otud6a−/−− mice also exhibited increased resistance to lethal HSV-1 and VSV infections, as well as LPS attacks due to decreased inflammatory responses. Mechanistically, mass spectrometry results revealed that UBC13 was an OTUD6A-interacting protein, and the interaction was significantly enhanced after HSV-1 stimulation. Taken together, our findings suggest that OTUD6A plays a crucial role in the innate immune response and may serve as a potential therapeutic target for infectious disease.

Microplastic pollution and changes to soil hydraulic characteristics affect the physical properties and functions of soil; however, knowledge remains limited on how microplastics influence soil hydraulic properties. Nonetheless, it is important to understand these relationships to maintain soil health and ensure sustainable land use, especially in the current “plastic age.” This case study explored how different particle sizes (20, 200, and 500 μm) and concentrations (up to 6%) of polypropylene microplastics affect the hydraulic properties of three soil textures (loam, clay, and sand). The results show that addition of microplastic reduced the saturated hydraulic conductivity (Ks) of the three soils by 69.79%, 77.11%, and 95.79%, respectively. These observed adverse effects of microplastics on the infiltration properties of the three studied soils were influenced by particle size, with larger particles having the weakest effect. Furthermore, microplastic addition reduced the water retention capacity of the clay to a greater extent than that of the loam and sand. In the case of clay, the slope of the water characteristic curve (SWRC) increased significantly, whereas the saturated water content (θs) and residual water content (θr) curves decreased significantly. Importantly, the interaction between microplastics and soil alters the soil pore-size distribution and reduces pore availability. Overall, this case study demonstrates the impact of microplastic on the hydraulic properties of different soil textures, which can inform management strategies to minimize the adverse effects of microplastic accumulation on yields where plastics are used in agricultural production.

In this work, we demonstrate that an organometallic perovskite (OP) single crystal for effective photodetection can be grown on a gold (Au)-decorated substrate using liquid phase epitaxy. The covered gold could both control the shape of the epitaxial layer and act as its electrodes. An MAPbCl3 single crystal and an MAPbBr1.5Cl1.5 single crystal were used as the substrate and the epitaxial layer, respectively. The device, with an Au-perovskite-Au structure, can be fully characterized. Due to the high-quality epitaxial layer, the maximum external quantum efficiency (EQE) value is over 60% under the voltage of −20 V. In addition, the response speed can reach 200 and 500 ns (ns) rise and fall, respectively. Our work provides an effective and promising method to fabricate efficient perovskite-based photodetectors.

With the large-scale deployment of datacenters in cloud computing,there is an increasing attention to their security issues.However,with the ossify deployment of traditional security devices,it is hard to meet the requirements of dynamical network security situation and copy with new kinds of security threats.Therefore,a service-oriented security framework for datacenter networks was proposed,which was able to compose the virtualized security functions flexibly and update the security policies dynamically based on virtualization technology and software-defined networking.With the implementation of prototype,the feasibility and availability of the proposed security framework was proved,and a solution to promote the flexibility and security of datacenter networks was provided.

The emergence of software-defined networking (SDN) and network function virtualization (NFV) facilitates policy-driven and dynamic service function chaining (SFC). In recent years, multi-domain SFC orchestration has attracted a significant attention, as it is a complicated problem involving many issues, such as corporation of various administrations and integration of heterogeneous underlying technologies. However, as another critical problem for multi-domain SFC deployment, how to achieve context-aware service provision is still not widely discussed. Thus, in this paper, based on the hierarchical SFC architecture, we allocate metadata to share context information of packets and realize context-based and dynamic SFC in multi-domain networks. We design typical use cases and conduct related experiments about location-aware flow steering and denial of service attack elimination. Experimental results confirm the feasibility and elasticity of our proposed approach. Furthermore, to alleviate the resource over-provisioning problem of context-aware SFC orchestration, we propose a consolidation-based SF placement and chaining algorithm with an online feedback mechanism. We compare the performance of our algorithm with a related greedy algorithm and a tabu search algorithm. Simulation results demonstrate that the proposed algorithm is efficient to reduce the reject rate and improve the revenue-cost ratio, with a compromise on node load balance.

To meet the urgent security demands, 5G aims to deploy virtualized and programmable security services and defense potential threats in real time. With the development of network function virtualization and software-defined networking, security functions can be dynamically and flexibly chained to cope with many types of malicious attacks. Although there are a number of studies on security function chaining for the 5G, they primarily focus on the security function composition, rather than rule enforcement. In fact, the misconfiguration of rules for security functions is notably common because of the security function diversity and rule heterogeneity that causes many unexpected and serious problems. Therefore, in this paper, we propose a priority-based anomaly-free mechanism with defined security rule anomalies. To avoid misconfiguration, we also propose and implement a simply configured rule management framework with anomaly resolution. With extensive performance evaluations, we show the availability and efficiency of our proposed mechanism to resolve security rule anomalies.

Mobile networks have urgent demands of fine-grained, cost-effective and flexible service provision for diversified user traffic. To cope with these demands, researchers have proposed various Service Function Chaining (SFC) solutions with the rise of Software Defined Networking (SDN) and Network Function Virtualization (NFV) technologies. However, most of them are performed based on MAC address and/or OpenFlow protocols without Network Service Header (NSH) support, having drawbacks in complexity, scalability and flexibility. NSH-based approaches are more promising for mobile networks, since they support metadata-based packet information sharing and policy enforcement. Moreover, a hierarchical SFC (hSFC) architecture is proposed to alleviate the scalability and management problems in large-scale networks. Nevertheless, how to realize application awareness and on-demand service provision has not been investigated thoroughly in the hSFC environment. Thus, in this paper, we propose a proactive-based branching approach for application-aware and dynamic security function chaining, where application features are analyzed at first, and then carried in the metadata of NSHs for subsequent processes by the relevant security functions. In this way, the data plane is able to redirect traffic based on metadata without the participation of control plane. Besides, we verify the proposed approach through our prototype system via two typical use cases, the application-aware traffic control and lawful interception, and the related experiment results confirm its feasibility and elasticity.

The areca (Areca catechu L.) nut kernel (ANK) is a good potential protein source for its high protein content of 9.89–14.62 g/100 g and a high yield of around 300,000 tons per year in China. However, utilization of the areca nut kernel is limited. To expand the usage of ANK in pharmaceutical or foods industries, areca nut kernel globulin was extracted and angiotensin-I converting enzyme (ACE) inhibition peptides were prepared and identified using gel chromatography, reversed phase HPLC separation, UPLC-ESI-MS/MS analysis and in silico screening. Finally, a novel ACE-inhibitory heptapeptide (Ala–Pro–Lys–Ile–Glu–Glu–Val) was identified and chemically synthesized. The combination pattern between APKIEEV and ACE, and the inhibition kinetics, antihypertensive effect and endothlein-1 inhibition activity of APKIEEV were studied. The results of the molecular docking demonstrated that APKIEEV could bind to four active sites (not the key active sites) of ACE via short hydrogen bonds and demonstrated high ACE-inhibitory activity (IC50: 550.41 μmol/L). Moreover, APKIEEV exhibited a significantly lowering effect on both the systolic blood pressure and diastolic blood pressure of spontaneously hypertensive rats, and had considerable suppression ability on intracellular endothelin-1. These results highlight the potential usage of APKIEEV as ingredients of antihypertensive drugs or functional foods.

In the title compound, C17H19N3O·CH3OH, the hydrazone molecule exists in a trans geometry with respect to the methylidene unit and the dihedral angle between the two substituted benzene rings is 42.6 (2)°. In the crystal, the components are linked through N—H...O and O—H...O hydrogen bonds, forming [100] chains of alternating hydrazone and methanol molecules.

BackgroundThe low positive rate of blood cultures often leads to downstream consequences. We present a summary of multidisciplinary interventions implemented by a tertiary referral hospital to improve blood culture efficiency and optimize antimicrobial usage.MethodsWe evaluated the knowledge, attitude, and practice (KAP) of healthcare workers in a tertiary care hospital before and after intervention using a questionnaire. A multidisciplinary team was formed to implement the intervention, defining roles, standardizing procedures, continually improving education and feedback, and establishing incentive mechanisms. Regular quality control assessments are conducted on the responsible departments.ResultsFollowing the intervention, the median submission time for blood culture specimens was reduced from 2.2 h to 1.3 h (p

The market and demanding of lactic acid bacteria and their products keep increasingly in recent years. However, it is difficult to maintain the activity of lactic acid bacteria during the processing and storage periods due to the stress caused by heating and oxygen exposure conditions for these anaerobic and heat-sensitive bacteria. This also causes a significant reduction in the quantity of live lactic acid bacteria in the end products. The activity of lactic acid bacteria will further decrease under the high acid condition in stomach and the high bile content in gut tract, which greatly reduce the end probiotic efficacy of this kind of probiotic products. Until now, numerous efforts have been made to enhance the tolerance of lactic and bacteria against heat, oxygen and gastrointestinal conditions, resulting in the emergence of several novel technologies. However, it is still challenging to select the most suitable technologies for practical application, as the results from various studies have not been thoroughly summarized and compared. In this study, the currently developed techniques for improving the activity of lactic acid bacteria during processing, under gastrointestinal condition, and in intestinal delivery are comprehensively summarized. The results from different studies are well compared. The application of electrostatic spinning, electrostatic spray, emulsion droplet technology, polyphenol nano armor, and heat induction pretreatment in the process of live lactic acid bacteria is also introduced. The information presented in this study can provide useful guidance for further research and the application of the currently developed techniques.