Vulnerability assessment for the hazards of crosswinds when vehicles cross a bridge deck

AbstractA new procedure to assess the crosswind hazard of operating a vehicle over a bridge deck has been developed using a probabilistic approach that utilizes long-term wind data at bridge sites as well as the aerodynamic properties of bridge decks and vehicles. The proposed procedure for safety assessment considers the probabilities of two accident types: sideslip and overturning. The vulnerability of vehicles to crosswinds is represented by the number of days for traffic control that would be required to secure vehicle safety over a period of one year. The distribution of wind speed over a bridge deck was estimated from a section model wind tunnel test. A sea-crossing bridge was selected as an example, and a series of case studies were performed to identify the influential factors affecting vehicle vulnerability to crosswinds: vehicle type and loaded weight, the position of a running vehicle over a bridge deck, the bridge alignment relative to the dominant wind direction, and vehicle speed

Inverse Association between High Blood 25-Hydroxyvitamin D Levels and Diabetic Retinopathy in a Representative Korean Population

Purpose To investigate the association between 25-hydroxyvitamin D and diabetic retinopathy (DR). Methods: A population-based cross-sectional study using a nation-wide, systemically stratified, multistage, clustered sampling method included a total of 18,363 subjects aged ≥40 years who participated in the Korean National Health and Nutrition Examination Survey during 2008–2012. All participants participated in standardized interviews, blood 25-hydroxyvitamin D level evaluations, and comprehensive ophthalmic examinations. Seven standard retinal fundus photographs were obtained from both eyes after pupil dilatation. DR was graded according to the modified Airlie House classification system. Results: The blood 25-hydroxyvitamin D levels were 19.2 ng/mL in men and 17.9 ng/mL in women. After adjusting for potential confounders, including age, sex, diabetes duration, hemoglobin A1c levels, and hypertension, the odds ratios (OR) for any DR and proliferative DR among men decreased significantly in the highest blood 25-hydroxyvitamin D level quintile relative to the lowest quintile (OR, 0.37; 95% confidence interval [CI], 0.18–0.76; P for trend = 0.004 and OR, 0.15; 95% CI, 0.03–0.83; P for trend = 0.043). Conclusions: This study provides the first epidemiologic findings of the inverse relationships of blood 25-hydroxyvitamin D levels with any DR and proliferative DR only in men. Considering anti-angiogenic and anti-fibrotic action of vitamin D, further studies including longitudinal and interventional analysis are warranted

Synthesis of nano-Li4Ti5O12 decorated on non-oxidized carbon nanotubes with enhanced rate capability for lithium-ion batteries

In this study, we report a facile strategy for the synthesis of Li4Ti5O12 nanoparticles (15-20 nm) uniformly decorated on non-oxidized carbon nanotubes (CNTs) for use as the anode material in Li-ion batteries. In the newly designed microwave solvothermal synthesis, the CNTs were used to selectively heat a substrate for facilitating the preferential precipitation of nanoparticles. The resulting sample delivered a reversible capacity of 172 mA h g(-1) at 1 C-rate and showed remarkable rate capability by maintaining 60% of the capacity at 60 C-rate (vs. 1 C-rate).

Evidence of pores and thinned lipid bilayers induced in oriented lipid membranes interacting with the antimicrobial peptides, magainin-2 and aurein-3.3

AbstractDynamic structures of supramolecular lipid assemblies, such as toroidal pores and thinned bilayers induced in oriented lipid membranes, which are interacting with membrane-acting antimicrobial peptides (AMPs), magainin-2 and aurein-3.3, were explored by 31P and 2H solid-state NMR (ssNMR) spectroscopy. Various types of phospholipid systems, such as POPC-d31, POPC-d31/POPG, and POPC-d31/cholesterol, were investigated to understand the membrane disruption mechanisms of magainin-2 and aurein-3.3 peptides at various peptide-to-lipid (P:L) ratios. The experimental lineshapes of anisotropic 31P and 2H ssNMR spectra measured on these peptide–lipid systems were simulated reasonably well by assuming the presence of supramolecular lipid assemblies, such as toroidal pores and thinned bilayers, in membranes. Furthermore, the observed decrease in the anisotropic frequency span of either 31P or 2H ssNMR spectra of oriented lipid bilayers, particularly when anionic POPG lipids are interacting with AMPs at high P:L ratios, can directly be explained by a thinned membrane surface model with fast lateral diffusive motions of lipids. The spectral analysis protocol we developed enables extraction of the lateral diffusion coefficients of lipids distributed on the curved surfaces of pores and thinned bilayers on a few nanometers scale

FEMALE PEASANTS AND THE ALTERNATIVE AGRI-FOOD MOVEMENT IN SOUTH KOREA: AGROECOLOGY AND THE KOREAN WOMEN PEASANT ASSOCIATION MOVEMENT

This paper examines the current state and socio-ecological implications of the alternative agri-food movement organized by the Korean Women Peasant Association (KWPA) in South Korea. In the process of rapid industrial development, South Korean farm sector has suffered from serious environmental problems, depopulation, and poverty. Food production itself has become mostly industrialized using abundant amount of chemical input. This, along with mass consumption system relying on large supermarkets, has led to an unsustainable food system. In this situation, there has been a rise of alternative agri-food movement by the KWPA. We have focused on the influence of agroecology in the KWPA’s activities, which might bring about a more sustainable food system. Under the dominant paradigm of agro-industrialism, farm production inevitably depends on outside resources. This de-contextualizes and disconnects farming from local ecosystems and social relations. Agroecology has emerged in recent years as an alternative paradigm, which can reconnect farming, nature, and society. We have analyzed the KWPA’s programs, such as the indigenous seed preservation movement (ISPM) and Sisters’ Garden Plot (SGP). We have found that agroecology plays an important role in the KWPA’s programs, which involve sharing indigenous farm knowledge; preserving and finding indigenous seeds; and providing seasonal, local, and organic food to the public. These activities have also led to the empowerment of female peasants. These as a whole could be important social resource for a transition to a more sustainable food system