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81.
Changing the air exchange rate of a home affects the annual thermal conditioning energy. Large-scale changes to air exchange rates of the housing stock can significantly alter the residential sector's energy consumption. However, the complexity of existing residential energy models is a barrier to the accurate quantification of the impact of policy changes on a state or national level. The Incremental Ventilation Energy (IVE) model introduced here combines the output of simple air exchange models with a limited set of housing characteristics to estimate the associated change in energy demand of homes. The IVE model was designed specifically to enable modellers to use existing databases of housing characteristics to determine the impact of ventilation policy change on a population scale. The IVE model estimates of energy change when applied to US homes with limited parameterization are shown to be comparable to the estimates of a well-validated, complex residential energy model.  相似文献   
82.
Curation or selection offers up probably the greatest challenge for the contemporary architect. With the onslaught of information, the emphasis is now on what an architect chooses to respond to rather than what is available to him or her in terms of sources. Iain Borden discusses how Block Architecture's responsive position enables the firm to react with immediacy to its urban surroundings, while also resulting in highly attuned ‘architectures of suggestion and momentary thinking’. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
83.
Summary Analytical results are given for whey powders prepared on a commercial or semi-commercial scale by three companies. Altogether, five preparations enriched in β-lactoglobulin, four whey protein isolates and a fraction enriched in α-lactalbumin were analyzed for protein composition, including %β-lactoglobulin, α-lactalbumin, bovine serum albumin, casein (glyco) macropeptide and the main triglycerides. Protein composition was determined by high pressure gel permeation and reversed phase liquid chromatography and by capillary zone electrophoresis. The extent of modification of the native β-lactoglobulin structure was also measured through the degree of lactosylation and the fraction of accessible free sulphydryl groups. One significant finding was that the calculated recovery of protein following quantitation of the chromatogram or electropherogram was seldom above 90% and occasionally below 60% of that loaded onto the column or capillary, raising doubts as to the reliability of the analytical results. Extrapolation by linear regression to 100% recovery allowed estimates to be made of the true β-lactoglobulin composition of the samples. The nine samples could be placed into three distinct groups with estimated true β-lactoglobulin weight % of 70.9 ± 1.1, 62.0 ± 3.4 and 39.5 ± 4.9. Physico-chemical properties of the group of samples are reported elsewhere (Holt et al ., 1999).  相似文献   
84.
Regulatory concerns in the semiconductor industry from both VOC emissions and solvent handling have prompted the desire to introduce water‐based formulations in spin‐coating fabrication processes. As resolution demands for i‐line lithography are driven to finer feature size and architecture, the need for antireflection coatings as a means of eliminating feature distortions from back reflected light is increasing. Common image irregularities, such as reflective notching and standing wave effects, can be effectively eliminated through application of an antireflection coating of optimal thickness between the resist layer and substrate. This work describes the design and development of novel side‐chain methacrylate copolymers for use in water‐based antireflection coating formulations. A pendant chromophore is incorporated into the polymer structure to allow optimization of the critical coating optical properties, refractive index, and absorption coefficient. The polymer solubility parameter and crosslinking density can be tailored by incorporation of appropriate functionality to allow compatibility with the device fabrication process. Terpolymers were designed, which were water‐soluble, had a thermally activated crosslinking mechanism, and contained a keto‐ester azobenzene chromophore that was highly absorbing at i‐line wavelength. Optical properties of polymer films were collected by spectroscopic elipsometry and utilized in the design process to identify the optimum chromophore structure. Lithographic images, fabricated utilizing these coatings, were of excellent quality, allowing critical dimension resolutions of less than 0.3 µm. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 1304–1316, 1999  相似文献   
85.
Organic semiconductors that can be fabricated by simple processing techniques and possess excellent electrical performance, are key requirements in the progress of organic electronics. Both high semiconductor charge-carrier mobility, optimized through understanding and control of the semiconductor microstructure, and stability of the semiconductor to ambient electrochemical oxidative processes are required. We report on new semiconducting liquid-crystalline thieno[3,2-b ]thiophene polymers, the enhancement in charge-carrier mobility achieved through highly organized morphology from processing in the mesophase, and the effects of exposure to both ambient and low-humidity air on the performance of transistor devices. Relatively large crystalline domain sizes on the length scale of lithographically accessible channel lengths ( approximately 200 nm) were exhibited in thin films, thus offering the potential for fabrication of single-crystal polymer transistors. Good transistor stability under static storage and operation in a low-humidity air environment was demonstrated, with charge-carrier field-effect mobilities of 0.2-0.6 cm(2) V(-1) s(-1) achieved under nitrogen.  相似文献   
86.
This paper is concerned with evaluating techniques to forecast plausible future scenarios in wind power production for up to 48 h ahead, where the term scenario refers to a coherent chronological prediction including the timing, rapidity and size of large changes. Such predictions are of great interest in power systems with high regional wind penetration where a large rapid change in wind power may pose a threat to power system security. Numerous studies have evaluated wind power forecasting methods on ex post statistical measures of forecast accuracy such as root mean square error. Other work has assessed the forecast value by simulating automated decision making for bidding wind generation into particular electricity markets, and in some cases, the ex ante value of a perfect forecast has been assessed. The future, however, will always be uncertain, and decision making always takes place in an ex ante context. This paper discusses how numerical weather prediction (NWP) systems forecasts are produced, with a particular focus on uncertainty and how forecasters might visually present plausible future scenarios for wind power to electricity industry decision makers. It is difficult to quantify the ex ante value of visual wind power forecast information to the complex decision‐making process involved. Consequently, this paper explores qualitative assessments of ex ante value by proposing six desirable attributes for the techniques and the presentation of NWP forecasts to decision makers. It uses these attributes to assess four such methodologies, which include NWP ensemble methods and the recently introduced NWP spatial field approach. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
87.
Frick F  Hume R  Robinson IC  Edén S  Oscarsson J 《Lipids》2008,43(4):313-324
Transgenic Late-onset OBesity (LOB) rats slowly develop a male-specific, autosomal dominant, obesity phenotype with a specific increase in peri-renal white adipose tissue (WAT) depot and preserved insulin sensitivity (Bains et al. in Endocrinology 145:2666–2679, 2004). To better understand the remarkable phenotype of these rats, the lipid metabolism was investigated in male LOB and non-transgenic (NT) littermates. Total plasma cholesterol (C) levels were normal but total plasma triacylglycerol (TAG) (2.8-fold) and hepatic TAG content (25%) was elevated in LOB males. Plasma VLDL-C and VLDL-TAG levels were higher while plasma apoB levels were 60% lower in LOB males. Increased hepatic TAG secretion explained the increased VLDL levels in LOB males. The hepatic gene expression of FAS, SCD-1, mitochondrial (mt)GPAT, and DGAT2 was up-regulated in both old obese and young non-obese LOB rats. Lipoprotein lipase (LPL) activity in heart and epididymal white adipose tissue (WAT) was unchanged, while LPL activity was increased in peri-renal WAT (30%) and decreased in soleus muscle (40%). Moreover, FAS, SCD-1 and DGAT2 gene expression was increased in peri-renal, but not in epididymal WAT. Basal lipolysis was reduced or unchanged and β-adrenergic stimulated lipolysis was reduced in WAT from both old obese and young non-obese LOB rats. To summarize, the obese phenotype of LOB male rats is associated with increased hepatic TAG production and secretion, a shift in LPL activity from skeletal muscle to WAT, reduced lipolytic response in WAT depots and a specific increase in expression of genes responsible for fatty acid and TAG synthesis in the peri-renal depot. F. Frick and R. Hume contributed equally to this work.  相似文献   
88.
89.
The potential of immunoassays as high-throughput screening tools for the detection of harmful substances in foods will only be realized when convenient methods are available for production of the high affinity antibodies needed for sensitive assay development. Recombinant antibodies offer advantages over traditional monoclonal antibodies in terms of ease of production, much greater antibody repertoire for selection, and versatility. We describe here the development of recombinant antibodies against the common shellfish toxin, domoic acid (DA), utilizing the sheep immunoglobulin system as an effective method for generating high affinity anti-hapten recombinant antibody fragments. A single-chain antibody fragment (scFv) library was generated from a sheep immunized with DA-bovine serum albumin conjugate, and anti-DA scFvs were isolated by phage-display. Three selected scFvs gave I50s of 2.6 to 58 ng/mL (8.3-186 nM) in competitive enzyme-linked immunosorbent assay (ELISA). Assay optimization with one of these scFvs gave a very reproducible standard curve with a range of 0.3 to 5.6 ng/mL (1.0 to 17.9 nM), a mean limit of quantification (LOQ, defined as the I20) of 0.5 ng/mL (1.6 nM), and a mean I50 of 1.2 ng/mL (3.9 nM). When the assay was used for the analysis of crude methanolic extracts of scallop tissues, results obtained correlated well with standard HPLC assay results (R2, 0.90, n = 40; R2, 0.81, n = 34), although ELISA results were lower than HPLC results. Adjusting the cutoff point for DA concentration accordingly from the regulatory 20 mg/kg, the potential of the sheep scFv-based ELISA for use as a screening assay for DA in shellfish extracts was demonstrated.  相似文献   
90.
Malaria is one of the world's most devastating parasitic diseases, causing almost one million deaths each year. Growing resistance to classical antimalarial drugs, such as chloroquine, necessitates the discovery of new therapeutic agents for successful control of this global disease. Here, we report the synthesis of some 6-halo-β-carbolines as analogues of the potent antimalarial natural product, manzamine A, retaining its heteroaromatic core whilst providing compounds with much improved synthetic accessibility. Two compounds displayed superior activity to chloroquine itself against a resistant Plasmodium falciparum strain, identifying them as promising leads for future development. Furthermore, in line with previous reports of similarities in antimalarial and antiprion effects of aminoaryl-based antimalarial agents, the 1-amino-β-carboline libraries were also found to possess significant bioactivity against a prion-infected cell line.  相似文献   
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