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611.
Thermodynamic data from model compounds indicate that proteins should be more stable in the unfolded form than in the folded form actually observed. The discrepancy can be resolved by including in the calculation the heat of fusion of solid model compounds, in accord with protein molecules being tightly packed, solid-like bodies rather than fluid.  相似文献   
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The lighting industry currently accounts for a significant proportion of all energy demand. Luminescent white lighting is often impure, inefficient, expensive, and detrimentally emits as a point source, meaning the light is emitted from a focused point. A luminescent light diffuser offers the potential to create a spatially broad lighting fixture. We developed a luminescent light diffuser consisting of three commercially available luminescent dye species (rhodamine 6G, fluorescein, 7-diethylamino-4-methylcoumarin) dispersed within a polymer matrix (polyvinyl alcohol), or commercial paint, and coated on a planar waveguide. A Light-emitting diode (LED) (385 nm) is directed into the waveguide which excites the luminescent species, coating the panel, creating a device that emits spatially broad pure white light. As the emission depends on escape cone emission from the waveguide, the device’s emission was found to depend highly on the coating film quality and components. We present two systems: a small 40 mm × 40 mm prototype, made using standard water-soluble polymer (polyvinyl alcohol), to study the underlying operational principles, and a 100 mm × 100 mm device with optimized efficiency fabricated with a clear commercial paint. By doping the polymer matrix with scattering silica microparticles we achieved a maximum photon outcoupling efficiency of 78%, whilst maintaining colour purity with an increased device size of more than 300 times (compared with the input LED). This work shows that it is possible to construct an inexpensive and spatially broad lighting source, whilst maintaining colour purity at a low cost.  相似文献   
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Globodera solanacearum females were found to have less than 0.01% of dry wt as sterols. Seven sterols were detected in the nematode, with stanols (campestanol and stigmastanol) making tip more than 50% of the total sterols present. Lipid amounted to 29.4% of the dry weight of the nematode. Triglyceride, free fatty acid, and phospholipid classes were composed predominantly of 20:4, 20:1, and 18:1 fatty acids. Of the total weight of fatty acids found in G. solanacearum females, the greatest portion occurred in the triglyceride fraction, followed by the free fatty acid fraction then the phospholipid fraction. Several unidentified hydrocarbons were detected in the nematode. Paraffinic hydrocarbons detected ranged in carbon length from C15 to C29. Total concentration of hydrocarbon composed 0.20% of the dry wt.  相似文献   
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Background  

Circadian clocks are internal daily time keeping mechanisms that allow organisms to anticipate daily changes in their environment and to organize their behavior and physiology in a coherent schedule. Although circadian clocks use temperature compensation mechanisms to maintain the same pace over a range of temperatures, they are also capable of synchronizing to daily temperature cycles. This study identifies key properties of this process.  相似文献   
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Books     
Book reviewed in this article:
Digital Futures: Living in a Dot-Com World, edited by James Wilsdon.  相似文献   
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