40 research outputs found

    Effects of nitrogen addition and plant litter manipulation on soil fungal and bacterial communities in a semiarid sandy land

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    The plant and soil microbial communities are influenced by variability in environmental conditions (e.g., nitrogen addition); however, it is unclear how long-term nitrogen addition and litter manipulation affect soil microbial communities in a semiarid sandy grassland. Therefore, we simulated the impact of N addition and litter manipulation (litter removal, litter doubling) on plant and soil microbial communities in Horqin grassland, northern China through an experiment from 2014 to 2019. Our results revealed that in the case of non-nitrogen (N0), litter manipulation significantly reduced vegetation coverage (V) (p < 0.05); soil bacterial communities have higher alpha diversity than that of the fungi, and the beta diversity of soil fungi was higher than that of the bacteria; soil microbial alpha diversity was significantly decreased by nitrogen addition (N10) (p < 0.05); N addition and litter manipulation had significantly interactive influences on soil microbial beta diversity, and litter manipulation (C0 and C2) had significantly decreased soil microbial beta diversity (p < 0.05) in the case of nitrogen addition (N10) (p < 0.05). Moreover, bacteria were mostly dominated by the universal phyla Proteobacteria, Actinobacteria, and Acidobacteria, and fungi were only dominated by Ascomycota. Furthermore, the correlation analysis, redundancy analysis (RDA), and variation partitioning analysis indicated that the soil fungi community was more apt to be influenced by plant community diversity. Our results provide evidence that plant and soil microbial community respond differently to the treatments of the 6-year N addition and litter manipulation in a semiarid sandy land

    Response to Pegylated Interferon Plus Ribavirin in Patients with Hepatitis C Virus Genotype 6a Infection from Guangdong and Guangxi Province of China

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    Aim. Our aim is to survey the treatment effect of PEG-IFN plus ribavirin in patients infected with HCV genotype 6a in Guangdong and Guangxi province of China and investigate best course of antiviral treatment for patients with HCV-6a infection. Methods. 515 eligible patients received subcutaneous 180 μg PEG-IFNα-2a or 1.5 μg/kg PEG-IFNα-2b once weekly plus oral ribavirin. Primary outcome was SVR by intention-to-treat analysis. Secondary outcome was RVR, cEVR, ETR, and relapse rate. Results. SVR in patients with HCV-6a infection treated for 48 weeks was comparable to that in patients with HCV-2/3 infection (80.9% versus 82.5%, p=0.812) and higher than that in patients with HCV-1b infection (80.9% versus 67.2%, p=0.014). ETR (98.9% versus 90.6%, p=0.016), virological response at month 3 of end-of- treatment (88.8% versus 76.6%, p=0.044), SVR (80.9% versus 65.6%, p=0.032), and virological response at month 12 of end-of-treatment (76.4% versus 60.9%, p=0.04) in patients with HCV-6a infection treated for 48 weeks were higher than those in patients with HCV-6a infection treated for 24 weeks. Conclusion. SVR in patients with HCV-6a treated for 48 weeks was comparable to that in patients with HCV-2/3 infection and higher than that in patients with HCV-1b infection; patients with HCV-6a infection treated for 48 weeks had a superior treatment response than patients treated for 24 weeks

    Night Shift Work: An Audio Documentary

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    Research indicates night shift workers are more likely to suffer health problems due to internal clock misalignment and difficulty sleeping during daytime hours. Their schedules can isolate them from others such as friends and families. Night shift workers have problems of disturbed sleep and wakefulness. The biggest difficulty is falling asleep, because the human body prefers to be awake during daytime hours. Because they can’t sleep well during the day, the vicious cycle of unrest may cause more serious health problems. Additionally, certain night shift workers are at increased risk for robbery and assault. This research lead to the creation of a short documentary. Through first-person interviews, Night Shift Workers, an audio documentary, explores these topics and more, including the eccentric personalities night shift workers encounter. The audio documentary director discusses the origin of the idea, production and post-production processes, and findings

    Two Scenario-Based Heuristics for Stochastic Shift Design Problem with Task-Based Demand

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    In this paper, we propose a deterministic shift design model with task-based demand and give the corresponding stochastic version with a probability constraint such that the shift plan designed is staffed with the workforce with a certain probability of performing all given tasks. Since we currently find no suitable methods for solving this stochastic model from the literature related to solving stochastic shift design models, we developed a single-stage heuristic method based on statistics, whose main idea is to reduce the occurrence of manpower shortage by prolonging the resource occupation time of a task, but this leads to a serious waste of resources, which is common in solving resource allocation problems with uncertain durations. To reduce the cost of wastage, we also propose a two-stage heuristic approach that is a two-stage heuristic with an evolutionary strategy. The two heuristics show their effectiveness in solving the proposed stochastic model in numerical experiments, and the two-stage heuristic significantly outperforms the one-stage heuristic in cost optimization and solution time stability

    Nanoscale MOF–Protein Composites for Theranostics

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    Nanoscale metal–organic frameworks (nMOFs) have gained increasingly more attention as attractive support materials in the immobilization and delivery of proteins for disease theranostics in recent years owing to their various advantages, such as large specific surface areas, well-ordered pore structures, aperture channel distributions, and ease of functionalization. Here, we present an overview of recent progress in nMOF–protein composites for disease theranostics. First, advantages and construction strategies of nMOF–protein composites as drug carriers are introduced. Then, therapeutic modalities and theranostic nanosystems based on nMOF–protein composites are reviewed. Next, we pay specific attention to their biosafety, biodistribution, and excretion in vivo. Finally, the challenges and limitations of nMOF–protein composites for biomedical applications are discussed, along with future perspectives in the field

    Research on Urban Distribution Routes Considering the Impact of Vehicle Speed on Carbon Emissions

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    To solve the low-carbon vehicle routing problem (VRP) with sustainable development background, the VRP considering the impact of vehicle speed on carbon emissions is studied. A vehicle routing optimization model aims to minimize the total cost of distribution, penalty cost and carbon emission cost. In the model, the driving time and carbon emissions are calculated on the basis of the varying vehicle speed matching the real road network. Moreover, the improved genetic algorithm is applied to optimize vehicle routing in this paper. Using the Solomon standard datasets, the experimental results validate the carbon emission cost and the total cost from the dynamic road network are lower than those from the static network; furthermore, the carbon emission cost and the total cost from the improved GE algorithm are much lower than those from the general GE algorithm in the dynamic road network. Obviously, the built model and the improved algorithm are more feasible and effective

    Litter Decomposition in a Semiarid Dune Grassland: Neutral Effect of Water Supply and Inhibitory Effect of Nitrogen Addition.

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    BACKGROUND:The decomposition of plant material in arid ecosystems is considered to be substantially controlled by water and N availability. The responses of litter decomposition to external N and water, however, remain controversial, and the interactive effects of supplementary N and water also have been largely unexamined. METHODOLOGY/PRINCIPAL FINDINGS:A 3.5-year field experiment with supplementary nitrogen and water was conducted to assess the effects of N and water addition on mass loss and nitrogen release in leaves and fine roots of three dominant plant species (i.e., Artemisia halondendron, Setaria viridis, and Phragmites australis) with contrasting substrate chemistry (e.g. N concentration, lignin content in this study) in a desertified dune grassland of Inner Mongolia, China. The treatments included N addition, water addition, combination of N and water, and an untreated control. The decomposition rate in both leaves and roots was related to the initial litter N and lignin concentrations of the three species. However, litter quality did not explain the slower mass loss in roots than in leaves in the present study, and thus warrant further research. Nitrogen addition, either alone or in combination with water, significantly inhibited dry mass loss and N release in the leaves and roots of the three species, whereas water input had little effect on the decomposition of leaf litter and fine roots, suggesting that there was no interactive effect of supplementary N and water on litter decomposition in this system. Furthermore, our results clearly indicate that the inhibitory effects of external N on dry mass loss and nitrogen release are relatively strong in high-lignin litter compared with low-lignin litter. CONCLUSION/SIGNIFICANCE:These findings suggest that increasing precipitation hardly facilitates ecosystem carbon turnover but atmospheric N deposition can enhance carbon sequestration and nitrogen retention in desertified dune grasslands of northern China. Additionally, litter quality of plant species should be considered when modelling the carbon cycle and nutrient dynamics of this system
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