Experimental Study of the Water Heating Performance of a Novel Tile-shaped Dual-function Solar Collector

AbstractSolar collectors are widely used in buildings for energy saving. However, the conventional solar collector does not match the tile roof of the building in appearance. To solve this problem, we propose a novel dual-function solar collector with tile-shaped Polymeric Methyl Methacrylate (PMMA) covers to match the roof appearance. This novel dual-function solar collector can provide hot air in winter and hot waterin other seasons, with high annual solar thermal utilization ratio. Experiments are conducted to investigate the performance of the tile-shaped collector. The efficiency of the novel tile-shaped dual-function solar collector varied from 53.2% to 69.1% in water heating mode in the test. The daily thermal efficiency of the water heating system with this tile-shaped collector system varied from 54.0% to 61.8%, while the daily thermal efficiency of the dual-function solar collector with semicircle covers varied from 44.7% to 59.2%, compared with the daily efficiency of the conventional dual-function solar collector without PMMA covers varied from 35.5% to 67.4%. It shows that the tile-shaped collector can greatly integrate the solar collector technology in to the local special feature buildings with slightly decrease of thermal efficiency

MyD88-dependent interplay between myeloid and endothelial cells in the initiation and progression of obesity-associated inflammatory diseases.

Low-grade systemic inflammation is often associated with metabolic syndrome, which plays a critical role in the development of the obesity-associated inflammatory diseases, including insulin resistance and atherosclerosis. Here, we investigate how Toll-like receptor-MyD88 signaling in myeloid and endothelial cells coordinately participates in the initiation and progression of high fat diet-induced systemic inflammation and metabolic inflammatory diseases. MyD88 deficiency in myeloid cells inhibits macrophage recruitment to adipose tissue and their switch to an M1-like phenotype. This is accompanied by substantially reduced diet-induced systemic inflammation, insulin resistance, and atherosclerosis. MyD88 deficiency in endothelial cells results in a moderate reduction in diet-induced adipose macrophage infiltration and M1 polarization, selective insulin sensitivity in adipose tissue, and amelioration of spontaneous atherosclerosis. Both in vivo and ex vivo studies suggest that MyD88-dependent GM-CSF production from the endothelial cells might play a critical role in the initiation of obesity-associated inflammation and development of atherosclerosis by priming the monocytes in the adipose and arterial tissues to differentiate into M1-like inflammatory macrophages. Collectively, these results implicate a critical MyD88-dependent interplay between myeloid and endothelial cells in the initiation and progression of obesity-associated inflammatory diseases

Reproductive Toxicity Assessment of Surface Water of the Tai Section of the Yangtze River, China by in vitro Bioassays Coupled With: Chemical Analysis. Environ. Pollut

a b s t r a c t Reproductive toxicity of organic extracts of the surface water from the Tai section of the Yangtze River was assessed by in vitro cytotoxity assays and selected persistent organic pollutants including PCBs, OCPs and PAHs were quantified by instrumental analysis. Eleven of the US EPA priority PAHs were detected. Individual PAHs were found to range from 0.7 to 20 ng/L. Concentrations of BaP did not exceed the national drinking water source quality standard of China. However, a 286-fold concentrated organic extract induced significant reproductive toxicity in adult male rats. The morphology of cells, MTT assay and LDH release assay were all affected by exposure to the organic extracts of water. The results of the reproductive toxicity indicated that PAHs posed the greatest risk of the chemicals studied. The compounds present in the water could be bioconcentrated and result in adverse effects

Significant contrasts in aerosol acidity between China and the United States

Aerosol acidity governs several key processes in aerosol physics and chemistry, thus affecting aerosol mass and composition and ultimately climate and human health. Previous studies have reported aerosol pH values separately in China and the United States (USA), implying different aerosol acidity between these two countries. However, there is debate about whether mass concentration or chemical composition is the more important driver of differences in aerosol acidity. A full picture of the pH difference and the underlying mechanisms responsible is hindered by the scarcity of simultaneous measurements of particle composition and gaseous species, especially in China. Here we conduct a comprehensive assessment of aerosol acidity in China and the USA using extended ground-level measurements and regional chemical transport model simulations. We show that aerosols in China are significantly less acidic than in the USA, with pH values 1&ndash;2&nbsp;units higher. Based on a proposed multivariable Taylor series method and a series of sensitivity tests, we identify major factors leading to the pH difference. Compared to the USA, China has much higher aerosol mass concentrations (gas + particle, by a factor of 8.4 on average) and a higher fraction of total ammonia (gas + particle) in the aerosol composition. Our assessment shows that the differences in mass concentrations and chemical composition play equally important roles in driving the aerosol pH difference between China and the USA &ndash; increasing the aerosol mass concentrations (by a factor of 8.4) but keeping the relative component contributions the same in the USA as the level in China increases the aerosol pH by &sim;&thinsp;1.0&nbsp;units and further shifting the chemical composition from US conditions to China's that are richer in ammonia increases the aerosol pH by &sim;&thinsp;0.9 units. Therefore, China being both more polluted than the USA and richer in ammonia explains the aerosol pH difference. The difference in aerosol acidity highlighted in the present study implies potential differences in formation mechanisms, physicochemical properties, and toxicity of aerosol particles in these two countries. &nbsp;</p

The everchanging epidemiology of meningococcal disease worldwide and the potential for prevention through vaccination.

Neisseria meningitidis is a major cause of bacterial meningitis and septicaemia worldwide and is associated with high case fatality rates and serious life-long complications among survivors. Twelve serogroups are recognised, of which six (A, B, C, W, X and Y) are responsible for nearly all cases of invasive meningococcal disease (IMD). The incidence of IMD and responsible serogroups vary widely both geographically and over time. For the first time, effective vaccines against all these serogroups are available or nearing licensure. Over the past two decades, IMD incidence has been declining across most parts of the world through a combination of successful meningococcal immunisation programmes and secular trends. The introduction of meningococcal C conjugate vaccines in the early 2000s was associated with rapid declines in meningococcal C disease, whilst implementation of a meningococcal A conjugate vaccine across the African meningitis belt led to near-elimination of meningococcal A disease. Consequently, other serogroups have become more important causes of IMD. In particular, the emergence of a hypervirulent meningococcal group W clone has led many countries to shift from monovalent meningococcal C to quadrivalent ACWY conjugate vaccines in their national immunisation programmes. Additionally, the recent licensure of two protein-based, broad-spectrum meningococcal B vaccines finally provides protection against the most common group responsible for childhood IMD across Europe and Australia. This review describes global IMD epidemiology across each continent and trends over time, the serogroups responsible for IMD, the impact of meningococcal immunisation programmes and future needs to eliminate this devastating disease

Bidirectional Correlation between Mechanics and Electrochemistry of Poly(vinyl alcohol)-Based Gel Polymer Electrolytes

The electrochemical–mechanical coupling property of solid electrolyte membranes is critical to improving the performance of solid-state energy storage devices. A new phenomenon was observed in which the electrochemical charge–discharge process induced aligned wrinkles on the edge of poly­(vinyl alcohol)-H₂SO₄ gel polymer electrolytes (GPEs), which is attributed to the deformation of polymer chains under electrochemical stimulation according to multiscale simulations. In the reverse direction, by means of modeling and testing, it was proved that the ionic conductivity of GPEs can be tuned by mediating the mechanical properties of GPEs via tailoring the polymer at the nanoscale. This bidirectional correlation reveals the coupling mechanisms between mechanical and electrochemical properties of GPEs and provides an insightful understanding of the origin and regulation of the ionic conductivity of GPEs, which is fundamental to improving the performance of GPEs

Bidirectional Correlation between Mechanics and Electrochemistry of Poly(vinyl alcohol)-Based Gel Polymer Electrolytes

The electrochemical–mechanical coupling property of solid electrolyte membranes is critical to improving the performance of solid-state energy storage devices. A new phenomenon was observed in which the electrochemical charge–discharge process induced aligned wrinkles on the edge of poly­(vinyl alcohol)-H₂SO₄ gel polymer electrolytes (GPEs), which is attributed to the deformation of polymer chains under electrochemical stimulation according to multiscale simulations. In the reverse direction, by means of modeling and testing, it was proved that the ionic conductivity of GPEs can be tuned by mediating the mechanical properties of GPEs via tailoring the polymer at the nanoscale. This bidirectional correlation reveals the coupling mechanisms between mechanical and electrochemical properties of GPEs and provides an insightful understanding of the origin and regulation of the ionic conductivity of GPEs, which is fundamental to improving the performance of GPEs

The Effects of Fire Disturbance on Litter Decomposition and C:N:P Stoichiometry in a Larix gmelinii Forest Ecosystem of Boreal China

Fire disturbance can affect the function of the boreal forest ecosystem through litter decomposition and nutrient element return. In this study, we selected the Larix gmelinii forest, a typical forest ecosystem in boreal China, to explore the effect of different years (3 years, 9 years, 28 years) after high burn severity fire disturbance on the decomposition rate (k) of leaf litter and the Carbon:Nitrogen:Phosphorus (C:N:P) stoichiometry characteristics. Our results indicated that compared with the unburned control stands, the k increased by 91&ndash;109% within 9 years after fire disturbance, but 28 years after fire disturbance the decomposition rate of the upper litter decreased by 45% compared with the unburned control stands. After fire disturbance, litter decomposition in boreal forests can be promoted in the short term (e.g., 9 years after a fire) and inhibited in the long term (e.g., 28 years after a fire). Changes in litter nutrient elements caused by the effect of fire disturbance on litter decomposition and on the C, N, and C:N of litter were the main litter stoichiometry factors for litter decomposition 28 years after fire disturbance. The findings of this research characterize the long-term dynamic change of litter decomposition in the boreal forest ecosystem, providing data and theoretical support for further exploring the relationship between fire and litter decomposition