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21.
Energy efficiency is a foundation of any good energy policy. The economic, security, and environmental benefits of energy efficiency have been recognized for decades. We explore energy efficiency investments derived from survey work in developing countries in 119 projects across nine manufacturing subsectors. The methodology utilizes financial return calculations to highlight gaps and opportunities for meeting the potential of energy efficiency projects in the manufacturing sector. We find a generally very high level of internal rates of return at a project level—with payback periods ranging from 0.9 to 2.9 years; but note that these metrics do not always appropriately influence corporate decision-making for a number of well-understood reasons.  相似文献   
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While yeast apoptosis was still a controversial issue less than 10 years ago, the efforts of many groups have revealed cell death mechanisms that resemble, in many aspects, those described for mammalian apoptosis. Here, we provide an overview of new insights on yeast apoptosis and the link with lifespan of yeast cells, based on data presented at the 6th International Meeting of Yeast Apoptosis (IMYA). Together, these data demonstrate the power and advantages of the yeast system to uncover novel cellular factors governing life and death, placing yeast at the forefront of apoptosis research. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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Waste soda-lime glass, alone or mixed with wastes from the manufacturing of glass fibers, was successfully converted into partially crystallized glass foams by a particularly simple and economic processing, consisting of a direct heating of glass powders at temperatures from 900 to 1050 °C. The foaming operated by the oxidation of SiC, inserted as powder additive, was found to depend on a complex combination of processing temperature, soaking time, tendency of the investigated glasses toward devitrification, and amount of MnO2, acting as oxidation promoter. Selected combinations led to foams with a good microstructural homogeneity and mechanical strength, suitable for application as aggregates in lightweight concrete.  相似文献   
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A well established technique for strengthening reinforced concrete (RC) members is based on the use of externally bonded (EB) FRP composites. Nevertheless, limited knowledge is available on the mechanical properties of FRP composites at extreme service environments. The performance of structural members strengthened with EB-FRP laminates exposed to extreme service temperatures or freeze–thaw cycles is mainly associated to either the bond between the FRP laminate and concrete substrate, or the mechanical properties of the laminates. This paper focuses on the latter aspects and presents results on a series of tensile tests of glass and carbon FRP (GFRP and CFRP) coupon specimens exposed to temperatures ranging between ?15 and +70 °C, or after freeze–thaw cycles, including FRP specimens with different number of plies. The experimental results for GFRP specimens indicate a low influence of ply number on FRP mechanical properties, and a minor reduction of axial tensile strength and strain with increasing the temperature. Results for CFRP specimens subjected to extreme service temperatures reflect a significant reduction of mechanical properties, while freeze–thaw cycles do not significantly influence the mechanical performance.  相似文献   
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The AA. studied the effects of a new anti-inflammatory drug on some spirographic and electrocardiographic parameters in a group of oarsmen. The results show a not significant changes of these parameters after drug engagement. The variations found are to be ascribed to the training.  相似文献   
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This paper reports the results of an experimental program to investigate the bonding behavior of two different types of fiber-reinforced polymer (FRP) systems for strengthening RC members: externally bonded carbon (EBR) plates and bars or strips externally applied with the near-surface-mounted (NSM) technique. The overall experimental program consisted of 18 bond tests on concrete specimens strengthened with EBR carbon plates and 24 bond tests on concrete specimens strengthened with NSM systems (carbon, basalt, and glass bars, and carbon strips). Single shear tests (SST) were carried out on concrete prisms with low compressive strengths to investigate the bonding behavior of existing RC structures strengthened with different types of FRP systems. The performance of each reinforcement system is presented, discussed, and compared in terms of failure mode, debonding load, load-slip relationship, and strain distribution. The findings indicate that the NSM technique could represent a sound alternative to EBR systems because it allows debonding to be delayed, and hence FRP tensile strength to be better exploited.  相似文献   
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Sodium appetite is an innate behavior occurring in response to sodium depletion that induces homeostatic responses such as the secretion of the mineralocorticoid hormone aldosterone from the zona glomerulosa of the adrenal cortex and the stimulation of the peptide hormone angiotensin II (ANG II). The synergistic action of these hormones signals to the brain the sodium appetite that represents the increased palatability for salt intake. This narrative review summarizes the main data dealing with the role of mineralocorticoid and ANG II receptors in the central control of sodium appetite. Appropriate keywords and MeSH terms were identified and searched in PubMed. References to original articles and reviews were examined, selected, and discussed. Several brain areas control sodium appetite, including the nucleus of the solitary tract, which contains aldosterone-sensitive HSD2 neurons, and the organum vasculosum lamina terminalis (OVLT) that contains ANG II-sensitive neurons. Furthermore, sodium appetite is under the control of signaling proteins such as mitogen-activated protein kinase (MAPK) and inositol 1,4,5-thriphosphate (IP3). ANG II stimulates salt intake via MAPK, while combined ANG II and aldosterone action induce sodium intake via the IP3 signaling pathway. Finally, aldosterone and ANG II stimulate OVLT neurons and suppress oxytocin secretion inhibiting the neuronal activity of the paraventricular nucleus, thus disinhibiting the OVLT activity to aldosterone and ANG II stimulation.  相似文献   
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