Net lipid transfer between lipoproteins in fish-eye disease plasma supplemented with normal high density lipoproteins

Native fish-eye disease plasma, which is deficient of both high density lipoproteins (HDL) and lecithin-cholesterol acyltransferase activity (α-LCAT), processing the free cholesterol of these lipoproteins, has been supplemented with normal isolated HDL₂ or HDL₃ and incubated in vitro at 37 C. After incubation for 0,7.5 and 24 hr the very low density (VLDL) and low density (LDL) lipoproteins as well as HDL were isolated, and their contents of triglycerides, phospholipids and free, esterified and total cholesterol were quantified. The resulting net mass transfer of the different lipids revealed a functioning transfer of cholesteryl esters and all other analyzed lipids between the lipoproteins, although no de novo esterification of the HDL cholesterol by LCAT in this plasma occurred. In accordance with previous findings there was a functioning esterification process of the free cholesterol of the combined VLDL and LDL of fish-eye disease plasma. The present results make it reasonable to conclude that the lack of HDL cholesterol esterification in this disease is not a result of a deficiency of cholesteryl ester transfer or lipid transfer activities.     

Localized surface plasmon resonance spectroscopy of single silver triangular nanoprisms

The plasmonic properties of single silver triangular nanoprisms are investigated using dark-field optical microscopy and spectroscopy. Two distinct localized surface plasmon resonances (LSPR) are observed. These are assigned as in-plane dipolar and quadrupolar plasmon excitations using electrodynamic modeling based on the discrete dipole approximation (DDA). The dipole resonance is found to be very intense, and its peak wavelength is extremely sensitive to the height, edge length, and tip sharpness of the triangular nanoprism. In contrast, the intensity of the quadrupole resonance is much weaker relative to the dipole resonance in the single particle spectra than in the ensemble averaged spectrum. Several parameters relevant to the chemical sensing properties of these nanoprisms have been measured. The dependence of the dipole plasmon resonance on the refractive index of the external medium is found to be as high as 205 nm RIU(-1) and the plasmon line width as narrow as approximately 0.17 eV. These data lead to a sensing figure of merit (FOM), the slope of refractive index sensitivity in eV RIU(-1)/line width (eV), as high as 3.3. In addition, the LSPR shift response to alkanethiol chain length was found to be linear with a slope of 4.4 nm per CH2 unit. This is the highest short-range refractive index sensitivity yet measured for a nanoparticle.     

Ammonia and nitrous oxide emissions from grass and alfalfa mulches

Ammonia (NH₃) and nitrous oxide (N_-2O) emissions were measured in the field for three months from three different herbage mulches and from bare soil, used as a control. The mulches were grass with a low N-content (1.15% N in DM), grass with a high N-content (2.12% N in DM) and alfalfa with a high N-content (4.33% N in DM). NH₃ volatilization was measured using a micrometeorological technique. N_-2O emissions were measured using closed chambers. NH₃ and N_-2O emissions were found to be much higher from the N-rich mulches than from the low-N grass and bare soil, which did not differ significantly. Volatilization losses of NH₃ and N_-2O occurred mainly during the first month after applying the herbage and were highest from wet material shortly after a rain. The extent of NH₃-N losses was difficult to estimate, due to the low frequency of measurements and some problems with the denuder technique, used on the first occasions of measurements. Nevertheless, the results indicate that NH₃-N losses from herbage mulch rich in N can be substantial. Estimated losses of NH₃-N ranged from the equivalent of 17% of the applied N for alfalfa to 39% for high-N grass. These losses not only represent a reduction in the fertilizer value of the mulch, but also contribute appreciably to atmospheric pollution. The estimated loss of N_-2O-N during the measurement period amounted to 1% of the applied N in the N-rich materials, which is equivalent to at least 13 kg N_-2O-N ha^-1 lost from alfalfa and 6 kg ha^-1 lost from high-N grass. These emission values greatly exceed the 0.2 kg N_-2O-N ha^-1 released from bare soil, and thus contribute to greenhouse gas emissions.     

Influence of different cold storage temperatures during the Rigor mortis phase on fillet contraction and longer-term quality changes of Atlantic cod fillets

Pre rigor produced fillets of Atlantic cod become shorter and more firm than post rigor produced fillets. In pre rigor excised muscle from warm-blooded animals and warm-water adapted fish, cold shortening, extensive contraction during cold storage, is known to occur. The aim of the present work was to study if the extent of fillet shortening in Atlantic cod could be reduced by a slight temperature increase during rigor contraction. The results demonstrate that fillets from this cold-water species showed no cold shortening. On the contrary, the fillets contracted the least when stored at 0 °C during rigor contraction.     

与自然共生

正如果你是各大家具展的忠实粉丝,相信你一定发现那些曾经充斥着造型华丽、用料奢华的家具早已不见了踪迹。相反,简约线条、质地天然的家具成为各大展览的焦点,他们以最清新、自然的状态向人们展示着全新的生活概念。如果说各大家具展拥有对潮流绝对的把控力与前瞻性的话,那么2013年的主流家具将不再仅局限于作为设计师们灵感的试验场,而是脱掉华丽的外衣,以平易近人的姿态,为人们营造出亲切、清新的自然家居氛围。M     

Variability in energy and carbon dioxide balances of wood and concrete building materials

A variety of factors affect the energy and CO₂ balances of building materials over their lifecycle. Previous studies have shown that the use of wood for construction generally results in lower energy use and CO₂ emission than does the use of concrete. To determine the uncertainties of this generality, we studied the changes in energy and CO₂ balances caused by variation of key parameters in the manufacture and use of the materials comprising a wood- and a concrete-framed building. Parameters considered were clinker production efficiency, blending of cement, crushing of aggregate, recycling of steel, lumber drying efficiency, material transportation distance, carbon intensity of fossil fuel, recovery of logging, sawmill, construction and demolition residues for biofuel, and growth and exploitation of surplus forest not needed for wood material production. We found the materials of the wood-framed building had lower energy and CO₂ balances than those of the concrete-framed building in all cases but one. Recovery of demolition and wood processing residues for use in place of fossil fuels contributed most significantly to the lower energy and CO₂ balances of wood-framed building materials. We conclude that the use of wood building material instead of concrete, coupled with greater integration of wood by-products into energy systems, would be an effective means of reducing fossil fuel use and net CO₂ emission to the atmosphere.