Global land surface temperature influenced by vegetation cover and PM2.5 from 2001 to 2016

Land surface temperature (LST) is an important parameter to evaluate environmental changes. In this paper, time series analysis was conducted to estimate the interannual variations in global LST from 2001 to 2016 based on moderate resolution imaging spectroradiometer (MODIS) LST, and normalized difference vegetation index (NDVI) products and fine particulate matter (PM2.5) data from the Atmospheric Composition Analysis Group. The results showed that LST, seasonally integrated normalized difference vegetation index (SINDVI), and PM2.5 increased by 0.17 K, 0.04, and 1.02 �g/m3 in the period of 2001–2016, respectively. During the past 16 years, LST showed an increasing trend in most areas, with two peaks of 1.58 K and 1.85 K at 72�N and 48�S, respectively. Marked warming also appeared in the Arctic. On the contrary, remarkable decrease in LST occurred in Antarctic. In most parts of the world, LST was affected by the variation in vegetation cover and air pollutant, which can be detected by the satellite. In the Northern Hemisphere, positive relations between SINDVI and LST were found; however, in the Southern Hemisphere, negative correlations were detected. The impact of PM2.5 on LST was more complex. On the whole, LST increased with a small increase in PM2.5 concentrations but decreased with a marked increase in PM2.5. The study provides insights on the complex relationship between vegetation cover, air pollution, and land surface temperature

25-Hydroxyvitamin D Levels and the Risk of Dementia and Alzheimer's Disease: A Dose–Response Meta-Analysis

Background and Purpose: Conclusions of previous cohort studies on the relationship between 25-hydroxyvitamin D level and the risk of dementia and Alzheimer's disease were not consistent. Thus, we performed a dose–response meta-analysis to evaluate this relationship by summarizing cohort studies.Methods: Pubmed, Embase, Cochrane, and Web of Science databases were searched for relevant studies. Cohort studies concerning the association between 25-hydroxyvitamin D level and dementia or Alzheimer's disease were included. Results of studies were pooled and the dose–response relationship was determined using a random-effect model.Results: Ten cohort studies, with 28,640 participants were included. A significant inverse relationship was found between 25-hydroxyvitamin D level and the risk of dementia and Alzheimer's disease. In addition, we found a linear dose–response relationship in that a 10 nmol/L increase in 25-hydroxyvitamin D level may lead to a 5% decrease in the risk of dementia (relative risk, 0.95; 95% confidence interval, 0.93–0.98) and 7% in the risk of Alzheimer's disease (relative risk, 0.93; 95% confidence interval, 0.89–0.97).Conclusion: Plasma or serum 25-hydroxyvitamin D concentration was inversely related to the risk of dementia and Alzheimer's disease, consistent with a linear dose–response relationship

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Improvement of Temperature Performance of Singlemode-Multimode-Singlemode Fiber Structure

A theoretical model for studying the temperature properties of singlemode-multimode-singlemode (SMS) fiber structure fabricated by absorptive multimode fiber (MMF) cladding is established. Moreover, an SMS-based temperature sensor is fabricated and experimentally demonstrated. Experimental results show that the dip wavelength of the transmission spectrum changes linearly with temperature, which is in good agreement with the simulated results obtained by using the model. Further, a comprehensive study of temperature characteristics affected by the thermo-optic effect, thermal expansion effect, and thermal effect of absorption characteristics is performed for SMS fiber optic structures with different refractive indexes, thermo-optic coefficients, and absorption properties of MMF cladding, MMF core diameters, and thermal expansion coefficients of packaging shell. According to the obtained rules, investigations are carried out into the thermal response of an SMS fiber structure resulting from combined thermal effects for temperature performance optimization. Excellent temperature stability with a temperature sensitivity of 0 pm/°C or good temperature sensitivity of −441.58 pm/°C is achieved accordingly

An application of scenario analysis forlong-term electricity destibution network development

This paper presents initial results of a research project entitled `Long-term Development Strategies for Electricity Distribution Networks'. The project aims at developing and applying (new) methodologies for dealing with uncertainties in asset management, more specifically, in the development of the electricity distribution network. In this paper, a traditional methodology, i.e. scenario analysis, is applied. Scenarios are developed taking electricity distribution network operators (DNOs) as problem owner. This paper presents the scenario development processes and the resulting scenarios

Research of the effect of compactness of fireproof mud plugging and proportion of backing material on fireproof performance

Building fire sealing technology is of great importance in preventing the spread of fire in buildings and reducing the damage caused by fire accidents. In order to investigate the influence of compactness, thickness and proportion of backing material on the fireproof performance of fireproof plugging material, this paper carries out experimental analysis on the pyrolysis process of fireproof plugging material to obtain the relevant parameters, and adopts a small-size fireproof mud-blocking combustion experimental platform to carry out combustion experiments. The experimental results prove that: with the increase of compactness, the thermal insulation and fireproofing performance of fireproof plugging material are enhanced; when the backing material is glass wool, the thermal insulation and fireproofing performance decreases with the increase of the proportion of glass wool; the expansion of fireproof plugging material caused by fire causes the hysteresis phase of thermal response in part of the cross section, and the time period of the hysteresis phase is delayed with the increase of compaction of fireproofing mud, and delayed with the decrease of the proportion of the thickness of backing material. The hysteresis phase is delayed with increasing compactness of fireproof plugging material and decreasing thickness of the backing material. The results of this paper can provide theoretical assistance for the expansion of fireproof plugging material by fire and for the process of installation

Association between MRI-detected knee joint regional effusion-synovitis and structural changes in older adults : a cohort study

Objective: To describe the cross-sectional and longitudinal associations between knee regional effusion-synovitis and structural changes in older adults. Methods: A total of 977 subjects were randomly selected from the local community (mean 62 years, 50% female) at baseline and 404 were followed up 2.6 years later. T2-weighted MRI was used to assess knee effusion-synovitis in four subregions: suprapatellar pouch, central portion, posterior femoral recess and subpopliteal recess. Knee cartilage defects, cartilage volume and bone marrow lesions (BMLs) were measured using MRI at baseline and follow-up. Results: Cross-sectionally, effusion-synovitis in most subregions was significantly associated with a higher risk of cartilage defects, BMLs and reduced cartilage volume. Longitudinally, suprapatellar pouch effusion-synovitis at baseline predicted an increase in cartilage defects (p<0.01), loss of cartilage volume (p=0.04) and an increase in BMLs (p=0.02) in multivariable analyses. The significant associations of effusion-synovitis with cartilage volume and BMLs disappeared after adjustment for cartilage defects. Effusion-synovitis in whole knee joint (p<0.01) and subpopliteal recess (p<0.05) was consistently associated with longitudinal changes in cartilage defects but not in cartilage volume and BMLs. Conclusions: There are independent associations between knee joint effusion-synovitis and knee cartilage defects in both cross-sectional and longitudinal analyses, suggesting a potential causal relationship. The associations of effusion-synovitis with BMLs and cartilage volume were largely dependent on cartilage defects, suggesting potential causal pathways.7 page(s