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Energy Demand (energy + demand)
Kinds of Energy Demand Selected AbstractsEnergy Demand and Climate Change.ANGEWANDTE CHEMIE, Issue 46 2009Issues, Resolutions. Wiley-VCH, Weinheim 2009. 251,S., Broschur, 24.90,,.,ISBN 978-3527324460 [source] Microwave-Assisted Kolbe-Schmitt Synthesis Using Ionic Liquids or Dimcarb as Reactive SolventsCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 11 2009A. Stark Abstract The activation of relatively inert carbon dioxide as a building block for organic products is of interest from both ecological and chemical points of view. One of the few industrially relevant processes using CO2 is the Kolbe-Schmitt synthesis. Two strategies to obtain the carboxylated product 2,4-dihydroxybenzoic acid from resorcinol are presented: both Dimcarb and hydrogencarbonate- or methylcarbonate-based ionic liquids are employed as reactive solvents in a microwave-assisted reaction. Reaction optimization shows that the ionic liquids are more reactive than Dimcarb. However, Dimcarb offers advantages with regard to ecological aspects, such as the Global Warming and Human Toxicity Potential and the Cumulative Energy Demand, which were assessed as part of the process development. [source] Pregnancy and lactation have anti-obesity and anti-diabetic effects in Ay/a miceACTA PHYSIOLOGICA, Issue 2 2010E. N. Makarova Abstract Aim:, Dominant ,yellow' mutation at the mouse agouti locus (Ay) results in obesity. Pregnancy and lactation are characterized by large energy demand. The aim of this study was to investigate whether obesity would develop in pregnant and suckling Ay mice. Methods:, Body weight and food intake in pregnancy, lactation, and after weaning, plasma leptin, insulin, corticosterone and blood glucose concentrations on days 7, 13 and 18 of pregnancy, days 1, 10, 21 and 80 postpartum, glucose and insulin tolerance on pregnancy days 7 and 18 were measured in C57Bl/6J mice of a/a (normal metabolism) and Ay/a genotypes. The same parameters were also measured in age-matched virgin females. Results:, Virgin Ay/a females exhibited hyperphagia, enhanced body weight, glucose intolerance and normal blood parameters at the mating age. With age, they developed obesity, hyperleptinaemia, hyperinsulinaemia and hyperglycaemia. Obesity did not develop in mated Ay/a mice; during suckling, they had equal food intake and body weight as a/a mice. During pregnancy, glucose tolerance was enhanced in Ay/a mice and became equal in both genotypes. In both genotypes, concentrations of hormones increased, and glucose decreased from pregnancy day 7 to day 18 and returned to normal values after parturition. Ay/a mice did not differ from a/a in corticosterone, insulin and glucose levels during pregnancy and lactation, in leptin levels during suckling; however, Ay/a mice had two times higher leptin levels than a/a during pregnancy. After weaning, Ay/a mice began to eat and weigh more than a/a exhibiting normal metabolic parameters for 50 days. Conclusion:, Pregnancy and lactation retard obesity and diabetes development in Ay mice. [source] Structure and function of AMP-activated protein kinaseACTA PHYSIOLOGICA, Issue 1 2009J. S. Oakhill Abstract AMP-activated protein kinase (AMPK) regulates metabolism in response to energy demand and supply. AMPK is activated in response to rises in intracellular AMP or calcium-mediated signalling and is responsible for phosphorylating a wide variety of substrates. Recent structural studies have revealed the architecture of the ,,, subunit interactions as well as the AMP binding pockets on the , subunit. The , catalytic domain (1,280) is autoinhibited by a C-terminal tail (313,335), which is proposed to interact with the small lobe of the catalytic domain by homology modelling with the MARK2 protein structure. Two direct activating drugs have been reported for AMPK, the thienopyridone compound A769662 and PTI, which may activate by distinct mechanisms. [source] Foraging energetics of arctic cormorants and the evolution of diving birdsECOLOGY LETTERS, Issue 3 2001David Grémillet Efficient body insulation is assumed to have enabled birds and mammals to colonize polar aquatic ecosystems. We challenge this concept by comparing the bioenergetics of cormorants (Phalacrocorax carbo) living in temperate and arctic conditions. We show that although these birds have limited insulation, they maintain high body temperature (42.3 °C) when diving in cold water (1,10 °C). Their energy demand at these times is extremely high (up to 60 W kg,1). Free-living cormorants wintering in Greenland (water temperature ,1 °C) profoundly alter their foraging activity, thus minimizing time spent in water and the associated high thermoregulatory costs. They then meet their daily food demand within a single intense dive bout (lasting 9 min on average). Their substantial energy requirements are balanced by the highest predatory efficiency so far recorded for aquatic predators. We postulate that similar behavioural patterns allowed early diving birds (Cretaceous) to colonize cold coastal areas before they evolved efficient insulation. [source] An operational algorithm for residential cogeneration systems based on the monitored daily-basis energy demandELECTRICAL ENGINEERING IN JAPAN, Issue 2 2010Yuka Yamagishi Abstract Residential cogeneration systems with PEFC are promising as distributed power system resources with the ability to improve energy system efficiency. However, it is important to develop an efficient algorithm for operation because the energy demand at each house differs greatly from day to day. In this paper, we propose an operational algorithm and evaluate it from the viewpoint of energy conservation and economic effectiveness based on the energy demand characteristics. In the algorithm, the hot water and electricity demand on the next day are estimated based on the average of past data. The results of simulations using actually monitored energy demand data indicate that (1) the greater the electrical demand of a household, the more effective this algorithm becomes with respect to energy conservation; (2) the greater the hot water demand of a household, the more effective this algorithm becomes with respect to economic effectiveness. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 170(2): 37,45, 2010; Published online in Wiley InterScience (www.interscience.wiley. com). DOI 10.1002/eej.20892 [source] Assessment of Fuel-Cell-Based Passenger CarsFUEL CELLS, Issue 3 2004T. Grube Abstract Highly efficient energy conversion systems with fuel cells for vehicles, as well as for stationary and portable applications, are currently being discussed all over the world. Fuel cell technology is expected to help reduce primary energy demand and emissions of limited and climate-relevant pollutants. The high flexibility of fuel cell systems with respect to energy carriers opens up possibilities of modifying the energy sector in the long term. Introducing new fuels based on low-carbon, or in the long term carbon-free, energy carriers can contribute to reducing greenhouse gas emissions as well as locally and regionally active atmospheric pollutants. The use of hydrogen as feed gas for fuel cells on the basis of it being a non-fossil, renewable energy, leads to special benefits with respect to conserving resources and climate protection, but at present still represents a medium- to long-term prospect. A major milestone on the road to market success for all energy conversion systems with fuel cells is the reduction of costs. The definition of the ,appropriate" fuel represents a serious obstacle to the market introduction of fuel-cell-powered vehicles. Presenting data from a well-to-wheel analysis of various vehicle fuel systems at FZJ this article aims to discuss the potential benefits of future vehicle concepts with fuel cells in terms of primary energy use and greenhouse gas emissions. Results from a comparison of international studies on this subject will be used to identify relevant assumptions that lead to different answers in the evaluation process. [source] Negative BOLD responses to epileptic spikesHUMAN BRAIN MAPPING, Issue 6 2006Eliane Kobayashi Abstract Simultaneous electroencephalogram/functional magnetic resonance imaging (EEG-fMRI) during interictal epileptiform discharges can result in positive (activation) and negative (deactivation) changes in the blood oxygenation level-dependent (BOLD) signal. Activation probably reflects increased neuronal activity and energy demand, but deactivation is more difficult to explain. Our objective was to evaluate the occurrence and significance of deactivations related to epileptiform discharges in epilepsy. We reviewed all EEG-fMRI studies from our database, identified those with robust responses (P = 0.01, with ,5 contiguous voxels with a |t| > 3.1, including ,1 voxel at |t| > 5.0), and divided them into three groups: activation (A = 8), deactivation (D = 9), and both responses (AD = 43). We correlated responses with discharge type and location and evaluated their spatial relationship with regions involved in the "default" brain state (Raichle et al. [2001]: Proc Natl Acad Sci 98:676,682]. Deactivations were seen in 52/60 studies (AD+D): 26 related to focal discharges, 12 bilateral, and 14 generalized. Deactivations were usually distant from anatomical areas related to the discharges and more frequently related to polyspike- and spike-and-slow waves than to spikes. The "default" pattern occurred in 10/43 AD studies, often associated with bursts of generalized discharges. In conclusion, deactivations are frequent, mostly with concomitant activation, for focal and generalized discharges. Discharges followed by a slow wave are more likely to result in deactivation, suggesting neuronal inhibition as the underlying phenomenon. Involvement of the "default" areas, related to bursts of generalized discharges, provides evidence of a subclinical effect of the discharges, temporarily suspending normal brain function in the resting state. Hum Brain Mapp, 2005. © 2005 Wiley-Liss, Inc. [source] Fixed Energy Storage Technology Applied for DC Electrified RailwayIEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 3 2010Takeshi Konishi Member Abstract The fixed energy storage system solves the problem of rising energy costs by reducing primary energy consumption. Without a fixed energy storage system, the energy generated by a braking vehicle would be simply converted into waste heat by its braking resistors if no other vehicles are powered simultaneously. Because, as a rule, such synchronized braking and powering cannot be coordinated, the energy storage system stores the energy generated during braking and discharges it again when a vehicle is powered. This greatly reduces primary energy demand in the substation. However, in addition to this energy saving, the energy storage system contributes to the reduction of CO2 emissions. The energy storage system also stabilizes the system voltage. Recent years have witnessed an advance in the energy storage media technology. Developments of energy storage media, lithium ion battery, nickel-metal hydride battery, and electric double-layer capacitors (EDLCs) have been remarkable. This study introduces technologies of fixed energy storage system applicable for DC electrified railway in Japan, and describes two examples of charge/discharge characteristics. Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source] Energy Conservation in Urban AreasIEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 1 2008Hideharu Sugihara Member Abstract This article outlines the energy conservation measures in the civilian sector from a few different viewpoint regarding energy conservation in cities. First, the energy consumption trends in the business and residential sectors are discussed, focusing the importance of energy conservation measures in applications such as home heating, water heating and specific power demand. Second, as a measure to reduce energy demand itself, energy conservation by way of applying heat insulating materials to buildings and changing the life style of residents is considered. And from the viewpoint of improving the energy system efficiency, additionally discussed here are the measures to improve the efficiency of each energy equipment such as air-conditioners and co-generation equipment, and the characteristics of District heating and cooling systems such as the local energy infrastructures. Lastly, from the knowledge obtained through model analyses by the authors, a scheme is recommended that would be one of the most efficient city-energy schemes where the energy systems including heat pumps, co-generators or equipment using solar power are utilized for their best-suited applications for business and residential customers. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source] Differences between young adults and elderly in thermal comfort, productivity, and thermal physiology in response to a moderate temperature drift and a steady-state conditionINDOOR AIR, Issue 4 2010L. Schellen Abstract, Results from naturally ventilated buildings show that allowing the indoor temperature to drift does not necessarily result in thermal discomfort and may allow for a reduction in energy use. However, for stationary conditions, several studies indicate that the thermal neutral temperature and optimum thermal condition differ between young adults and elderly. There is a lack of studies that describe the effect of aging on thermal comfort and productivity during a moderate temperature drift. In this study, the effect of a moderate temperature drift on physiological responses, thermal comfort, and productivity of eight young adults (age 22,25 year) and eight older subjects (age 67,73 year) was investigated. They were exposed to two different conditions: S1-a control condition; constant temperature of 21.5°C; duration: 8 h; and S2-a transient condition; temperature range: 17,25°C, duration: 8 h, temperature drift: first 4 h: +2 K/h, last 4 h: ,2 K/h. The results indicate that thermal sensation of the elderly was, in general, 0.5 scale units lower in comparison with their younger counterparts. Furthermore, the elderly showed more distal vasoconstriction during both conditions. Nevertheless, TS of the elderly was related to air temperature only, while TS of the younger adults also was related to skin temperature. During the constant temperature session, the elderly preferred a higher temperature in comparison with the young adults. Practical Implications ,Because the stock of fossil fuels is limited, energy savings play an important role. Thermal comfort is one of the most important performance indicators to successfully apply measures to reduce the energy need in buildings. Allowing drifts in indoor temperature is one of the options to reduce the energy demand. This study contributes to the knowledge concerning the effects of a moderate temperature drift and the age of the inhabitants on their thermal comfort. [source] Potential of biomass-fired combined heat and power plants considering the spatial distribution of biomass supply and heat demandINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 11 2010Johannes Schmidt Abstract Combined heat and power (CHP) plants fired by forest wood can significantly contribute to attaining the target of increasing the share of renewable energy production. However, the spatial distribution of biomass supply and of heat demand limits the potentials of CHP production. This article assesses CHP potentials using a mixed integer programming model that optimizes locations of bioenergy plants. Investment costs of district heating infrastructure are modeled as a function of heat demand densities, which can differ substantially. Gasification of biomass in a combined cycle process is assumed as production technology. Some model parameters have a broad range according to a literature review. Monte-Carlo simulations have therefore been performed to account for model parameter uncertainty in our analysis. The model is applied to assess CHP potentials in Austria. Optimal locations of plants are clustered around big cities in the east of the country. At current power prices, biomass-based CHP production allows producing around 3% of the total energy demand in Austria. Yet, the heat utilization decreases when CHP production increases due to limited heat demand that is suitable for district heating. Production potentials are most sensitive to biomass costs and power prices. Copyright © 2009 John Wiley & Sons, Ltd. [source] Financial costs and environmental impact optimization of the energy supply systemsINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 1 2002L. I. González-Monroy Abstract We have designed and implemented a tool to evaluate and optimize energy supply systems, so that the financial costs, the consumption of primary energy or the amount of harmful emission to the environment are minimized. We have set-up a general description of these systems and have applied a heuristic optimization method, Simulated Annealing, that allows us, in an efficient way, to determine the best way to fulfil different types of energy demand using a set of facilities of energy transformation and storage. We have also considered the time correlation introduced by the storage devices or transport processes and the possible behaviour of the system when the external conditions (fuel prices, demand profiles, etc.) change. Copyright © 2002 John Wiley & Sons, Ltd. [source] Assessment of the Automobile Assembly Paint Process for Energy, Environmental, and Economic ImprovementJOURNAL OF INDUSTRIAL ECOLOGY, Issue 1-2 2004Geoffrey J. Roelant A coat of paint adds considerable value to an automobile. In addition to consuming up to 60% of the energy needed by automobile assembly plants, however, the painting process also creates both economic and environmental impacts. This study investigated the degree of cost and environmental impact improvement that can be expected when modifications are considered for existing paint processes through heat integration. In order to accomplish this goal, a mathematical model was created to describe the energy use, costs, and environmental impacts from energy consumption in an automobile assembly painting facility. The model agrees with measured energy consumption data for process heating and electricity demand to within about 15% for one Michigan truck facility from which model input parameters were obtained. Thermal pinch analysis determined an energy conservation target of 58% of paint process energy demand. A heat exchanger network optimization study was conducted in order to determine how closely the network design could achieve this target. The resulting heat exchanger network design was profitable based on a discounted cash flow analysis and may achieve reductions in total corporate energy consumption of up to 16% if implemented corporatewide at a major automobile manufacturer. [source] Marginal Land-based Biomass Energy Production in ChinaJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 1 2010Ya Tang Fast economic development in China has resulted in a significant increase in energy demand. Coal accounts for 70% of China's primary energy consumption and its combustion has caused many environmental and health problems. Energy security and environmental protection requirements are the main drivers for renewable energy development in China. Small farmland and food security make bioenergy derived from corn or sugarcane unacceptable to China: the focus should be on generating bioenergy from ligno-cellulosic feedstock sources. As China cannot afford biomass energy production from its croplands, marginal lands may play an important role in biomass energy production. Although on a small scale, marginal land has already been used for various purposes. It is estimated that some 45 million hm2 of marginal land could be brought into high potential biomass energy production. For the success of such an initiative, it will likely be necessary to develop multipurpose plants. A case study, carried out on marginal land in Ningnan County, Sichuan Province with per capita cropland of 0.07 ha, indicated that some 380 000 tons of dry biomass could be produced each year from annual pruning of mulberry trees. This study supports the feasibility of producing large quantities of biomass from marginal land sources. [source] Increased Caloric Intake on a Fat-Rich Diet: Role of Ovarian Steroids and Galanin in the Medial Preoptic and Paraventricular Nuclei and Anterior Pituitary of Female RatsJOURNAL OF NEUROENDOCRINOLOGY, Issue 10 2007S. F. Leibowitz Previous studies in male rats have demonstrated that the orexigenic peptide galanin (GAL), in neurones of the anterior parvocellular region of the paraventricular nucleus (aPVN) projecting to the median eminence (ME), is stimulated by consumption of a high-fat diet and may have a role in the hyperphagia induced by fat. In addition to confirming this relationship in female rats and distinguishing the aPVN-ME from other hypothalamic areas, the present study identified two additional extra-hypothalamic sites where GAL is stimulated by dietary fat in females but not males. These sites were the medial preoptic nucleus (MPN), located immediately rostral to the aPVN, and the anterior pituitary (AP). The involvement of ovarian steroids, oestradiol (E2) and progesterone (PROG), in this phenomenon was suggested by an observed increase in circulating levels of these hormones and GAL in MPN and AP with fat consumption and an attenuation of this effect on GAL in ovariectomised (OVX) rats. Furthermore, in the same four areas affected by dietary fat, levels of GAL mRNA and peptide immunoreactivity were stimulated by E2 and further by PROG replacement in E2 -primed OVX rats and were higher in females compared to males. Because both GAL and PROG stimulate feeding, their increase on a fat-rich diet may have functional consequences in females, possibly contributing to the increased caloric intake induced by dietary fat. This is supported by the findings that PROG administration in E2 -primed OVX rats reverses the inhibitory effect of E2 on total caloric intake while increasing voluntary fat ingestion, and that female rats with higher GAL exhibit increased preference for fat compared to males. Thus, ovarian steroids may function together with GAL in a neurocircuit, involving the MPN, aPVN, ME and AP, which coordinate feeding behaviour with reproductive function to promote consumption of a fat-rich diet at times of increased energy demand. [source] Mitochondrial dysfunction in a neural cell model of spinal muscular atrophyJOURNAL OF NEUROSCIENCE RESEARCH, Issue 12 2009Gyula Acsadi Abstract Mutations of the survival motor neuron (SMN) gene in spinal muscular atrophy (SMA) lead to anterior horn cell death. The cause is unknown, but motor neurons depend substantially on mitochondrial oxidative phosphorylation (OxPhos) for normal function. Therefore, mitochondrial parameters were analyzed in an SMA cell culture model using small interfering RNA (siRNA) transfection that decreased Smn expression in NSC-34 cells to disease levels. Smn siRNA knock-down resulted in 35% and 66% reduced Smn protein levels 48 and 72 hr posttransfection, respectively. ATP levels were reduced by 14% and 26% at 48 and 72 hr posttransfection, respectively, suggesting decreased ATP production or increased energy demand in neural cells. Smn knock-down resulted in increased mitochondrial membrane potential and increased free radical production. Changes in activity of cytochrome c oxidase (CcO), a key OxPhos component, were observed at 72 hr with a 26% increase in oxygen consumption. This suggests a compensatory activation of the aerobic pathway, resulting in increased mitochondrial membrane potentials, a condition known to lead to the observed increase in free radical production. Further testing suggested that changes in ATP at 24 hr precede observable indices of cell injury at 48 hr. We propose that energy paucity and increased mitochondrial free radical production lead to accumulated cell damage and eventual cell death in Smn-depleted neural cells. Mitochondrial dysfunction may therefore be important in SMA pathology and may represent a new therapeutic target. © 2009 Wiley-Liss, Inc. [source] Neuroprotective effect of riluzole in a primate model of Parkinson's disease: Behavioral and histological evidenceMOVEMENT DISORDERS, Issue 1 2002Maria C. Obinu PhD Abstract Our study aimed to determine whether riluzole, which has shown efficacy as a disease-modifying agent in amyotrophic lateral sclerosis (ALS), is neuroprotective in a marmoset model of Parkinson's disease (PD). Reduction of energy demand by riluzole could be a rational neuroprotective strategy with good tolerability. The efficacy of riluzole was evaluated in marmosets by testing its ability to reduce MPTP-induced behavioral deficits and loss of dopaminergic nigral neurons. Marmosets were divided into two groups of four animals each: animals in Group 1 were injected twice with MPTP (2 mg/kg subcutaneous) and treated with riluzole (10 mg/kg per os b.i.d.), animals in Group 2 (controls) were injected with MPTP and with the vehicle of riluzole. A third group of marmosets which did not receive MPTP or riluzole drug was introduced for neurohistopathological studies (normal animals). Marmosets treated with riluzole preserved a better motor function and neurological performance through the 26 days of assessment when compared with the controls. Histologically, there was sparing of TH- and Nissl-stained nigral neurons and of TH-stained terminals in the striatum and the putamen in the group treated with riluzole compared to the controls. We conclude that riluzole protects dopaminergic neurons and reduces behavioral deficits in a marmoset model of PD. © 2001 Movement Disorder Society. [source] Quantification of metabolites in breast cancer patients with different clinical prognosis using HR MAS MR spectroscopyNMR IN BIOMEDICINE, Issue 4 2010Beathe Sitter Abstract Absolute quantitative measures of breast cancer tissue metabolites can increase our understanding of biological processes. Electronic REference To access In vivo Concentrations (ERETIC) was applied to high resolution magic angle spinning MR spectroscopy (HR MAS MRS) to quantify metabolites in intact breast cancer samples. The ERETIC signal was calibrated using solutions of creatine and TSP. The largest relative errors of the ERETIC method were 8.4%, compared to 4.4% for the HR MAS MRS method using TSP as a standard. The same MR experimental procedure was applied to intact tissue samples from breast cancer patients with clinically defined good (n,=,13) and poor (n,=,16) prognosis. All samples were examined by histopathology for relative content of different tissue types and proliferation index (MIB-1) after MR analysis. The resulting spectra were analyzed by quantification of tissue metabolites (,-glucose, lactate, glycine, myo-inositol, taurine, glycerophosphocholine, phosphocholine, choline and creatine), by peak area ratios and by principal component analysis. We found a trend toward lower concentrations of glycine in patients with good prognosis (1.1,µmol/g) compared to patients with poor prognosis (1.9,µmol/g, p,=,0.067). Tissue metabolite concentrations (except for ,-glucose) were also found to correlate to the fraction of tumor, connective, fat or glandular tissue by Pearson correlation analysis. Tissue concentrations of ,-glucose correlated to proliferation index (MIB-1) with a negative correlation factor (,0.45, p,=,0.015), consistent with increased energy demand in proliferating tumor cells. By analyzing several metabolites simultaneously, either in ratios or by metabolic profiles analyzed by PCA, we found that tissue metabolites correlate to patients' prognoses and health status five years after surgery. This study shows that the diagnostic and prognostic potential in MR metabolite analysis of breast cancer tissue is greater when combining multiple metabolites (MR Metabolomics). Copyright © 2010 John Wiley & Sons, Ltd. [source] Underlying consumer preferences and their contribution to energy demandOPEC ENERGY REVIEW, Issue 3-4 2009Olutomi I. Adeyemi The demand for energy is not simply a function of price and income, but can be shown to also be a function of the underlying energy demand trend (UEDT). The UEDT not only captures behavioural responses to non-fiscal instruments, including technological change, but also encapsulates attitudinal responses/changes in demand that might result, for instance, from increased public awareness of how environmentally damaging energy use can be; hence, reflecting underlying consumer preferences. This study estimates a longitudinal econometric model for the aggregate demand functions of a sample of 17 Organisation for Economic Co-operation and Development countries for the period 1960,2005. This approach to modelling will enable UEDTs to be observed for each of the countries, as well as normal price and income elasticities. The model results will provide an indication of the extent to which price/income-based instruments can be used to reduce the demand for energy, as well as indicating the extent to which consumers have responded to non-price/income instruments. [source] Sustaining economic expansion in Pakistan in an era of energy shortfalls: growth options to 20351OPEC ENERGY REVIEW, Issue 2 2007Robert Looney Pakistan's recent economic acceleration together with rapid rates of population growth is having a significant impact on the country's energy supply/demand balances. Energy supplies in turn affect the pace and pattern of the country's economic expansion. Drawing on the empirically-based complex links between energy and the economy, several alternative scenarios of growth and energy needs are developed in an attempt to answer several key questions. In particular, what are some of the key interrelationships between sources of energy demand and supply? What are the economic growth consequences of alternative energy availabilities and, in turn, how do these growth patterns affect the subsequent energy supply and demand patterns? What energy strategies are suggested by the interconnection between the country growth requirements and energy needs? Are these significantly modified under rising or falling energy prices? Based on this analysis, several guidelines are drawn for the country's future energy policy. [source] Industrial energy policy: a case study of demand in KuwaitOPEC ENERGY REVIEW, Issue 2 2006M. Nagy Eltony The purpose behind building the industrial energy demand model was to enable assessment of the impact of potential policy options and to forecast future energy demand under various assumptions, including the impact of the possible removal of energy subsidies in accordance with the World Trade Organization (WTO) agreement. The results of the model, based on three scenarios, underline several important issues: With nominal energy prices staying the same (the status quo) and with inflation and economic growth continuing to expand (i.e. baseline scenario), it is expected that industrial demand will grow. In this sector, energy consumption is projected to grow at an annual growth rate of about 3.5 per cent throughout the forecast period. In the moderate scenario, however, this drops to 1.9 per cent and when all energy subsidies are removed as in the case of the extreme scenario, the energy consumption is projected to grow by only 1.5 per cent annually throughout the same period. Moreover, with regards to inter-fuel substitution, the model forecast indicates that electricity and natural gas consumption will decline, while the consumption of oil products will increase in all scenarios. The results of the model also indicate that the changing price structure of energy resources should be done in a comprehensive manner. In other words, electricity prices should be adjusted upwards instantly with the adjustment of oil products' prices and natural gas otherwise, a massive inter-fuel substitution will occur within the various consuming industries. [source] Comparative gene expression analysis reveals a characteristic molecular profile of the superior olivary complexTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 4 2006Hans Gerd Nothwang Abstract The superior olivary complex (SOC) is a very conspicuous structure in the mammalian auditory brainstem. It represents the first binaural processing center and is important for sound localization in the azimuth and in feedback regulation of cochlear function. In order to define molecular determinants of the SOC, which are of potential functional relevance, we have performed a comprehensive analysis of its transcriptome by serial analysis of gene expression in adult rats. Here, we performed a detailed analysis of the SOC's gene expression profile compared to that of two other neural tissues, the striatum and the hippocampus, and with extraocular muscle tissue. This tested the hypothesis that SOC-specific or significantly upregulated transcripts provide candidates for the specific function of auditory neurons. Thirty-three genes were significantly upregulated in the SOC when compared to the two other neural tissues. Thirteen encoded proteins involved in neurotransmission, including action potential propagation, exocytosis, and myelination; five genes are important for the energy metabolism, and five transcripts are unknown or poorly characterized and have yet to be described in the nervous system. The comparison of functional gene classes indicates that the SOC has the highest energy demand of the three neural tissues, yet protein turnover is apparently not increased. This suggests a high energy demand for fueling auditory neurotransmission. Such a demand may have implications on auditory-specific tasks and relate to central auditory processing disorders. Ultimately, these data provide new avenues to foster investigations of auditory function and to advance molecular physiology in the central auditory system. Anat Rec Part A, 2006. © 2006 Wiley-Liss, Inc. [source] What changes energy consumption?THE RAND JOURNAL OF ECONOMICS, Issue 3 2008Prices, public pressures Policymakers often seek to limit energy prices following market shocks, and instead issue public appeals to reduce demand. This article presents new evidence on how price changes and conservation appeals affect energy consumption, using household-level data from California's energy crisis during 2000 and 2001. The evidence indicates that when policymakers cap energy prices following market shocks, they preclude substantial,and quite rapid,reductions in energy use. The data also reveal that conservation appeals and informational programs can produce sustained reductions in energy demand. [source] Seasonally changing metabolism in Atlantic salmon (Salmo salar L.) II ,, -oxidation capacity and fatty acid composition in muscle tissues and plasma lipoproteinsAQUACULTURE NUTRITION, Issue 5 2003U. Nordgarden Abstract With the aim of elucidating seasonally changing lipid metabolism in immature Atlantic salmon (Salmo salar L.) in sea water, one group was reared under simulated natural light, while one group was reared under continuous light. Fatty acid profile in plasma lipoproteins did not vary during the experiment, while , -oxidation capacity increased during spring, concurrent with decreasing temperatures. Simultaneously, the relative level of monounsaturated fatty acids (MUFA) in muscle tissue decreased (42,36%). Muscle levels of saturated fatty acids were low during early spring (19%), but then increased slowly, and muscle levels of polyunsaturated fatty acids increased during spring (from 36% to 39%). It is suggested that increased spring growth and the concomitant energy demand was met by increased lipid oxidation, where MUFA were preferred as energy substrate. [source] Qualitätsprüfung für Energieausweis-SoftwareBAUPHYSIK, Issue 3 2009Klaus Fehlauer Prof. Dr. Dr. Energieeinsparung; Technische Regelwerke Abstract Nach der Einführung der Energieeinsparverordnung 2007 (EnEV 2007) beauftragte das Bundesamt für Bauwesen und Raumordnung (BBR) ein Forschungsprojekt, um die am Markt verfügbare Software zur EnEV 2007 einer Qualitätsprüfung zu unterziehen. Der Zweck des Projektes war die Prüfung hinsichtlich einer korrekten Nachweisführung und Energiepassausstellung sowie die Erarbeitung von Methoden zur Qualitätsprüfung und -sicherung mit dem Ziel, Transparenz bei den am Markt vorhandenen Softwarelösungen zu schaffen. Darüber hinaus sollte durch die Bereitstellung von Testmodulen die Möglichkeit geschaffen werden, vorhandene Softwareprodukte durch das Aufdecken von Mängeln stetig weiter zu entwickeln, um so die Qualität der Produkte auf hohem Niveau dauerhaft zu sichern. Es wurden 15 Softwareprogramme für Nichtwohngebäude und 13 Programme für Wohngebäude für die Bedarfsberechnung nach DIN 4108-6 und DIN V 4701-10 und für Verbrauchsausweiserstellung untersucht. Im Rahmen dieser Veröffentlichung wurden schwerpunktmäßig die Ergebnisse für die Bedarfsberechnungen auf Basis von DIN V 18599 für den Nichtwohngebäudebereich vorgestellt. Quality tests for Energy Passport software. Shortly after the introduction of the 2007 Building Energy Conservation Ordinance (EnEV 2007), the German Institute for Applied Information Technology in Construction (IAIB) was commissioned by the German Federal Office for Building and Regional Planning (BBR) to carry out quality tests for the EnEV 2007 software available on the market. The specified project aims were to check calculation and Energy Passport issuing procedures and the development of quality assurance methods with the aim of creating transparency regarding the software solutions available on the market. 15 software programs for office buildings and 13 software programs for residential buildings were examined with regard to the determination of energy demand according to DIN V 18599 and with regard to energy consumption. [source] Die Ermittlung des Jahresnutzkühlenergiebedarfs in Bürogebäuden mit dem Berechnungsverfahren nach Energieeinsparverordnung 2007 bzw.BAUPHYSIK, Issue 2 2009DIN V 1859 Energieinsparung; Technische Regelwerke Abstract Die seit 2007 gültige Energieeinsparverordnung (EnEV) schreibt für Bürogebäude eine gesamtheitliche Bilanzierung des Energiebedarfs vor, so dass neben dem Heizwärmeverbrauch und dem Energieverbrauch für Lüftungsanlagen erstmals auch der Kühlenergieverbrauch und der Stromverbrauch für Beleuchtung zu berücksichtigen ist. Die vorliegende Studie fokussiert auf den Jahreskühlenergieverbrauch von Büroräumen, welcher neben den Rechenregeln nach EnEV 2007 bzw. DIN V 18599 auch mit Hilfe der Algorithmen in der VDI 2067 oder mittels dynamischer, thermischer Simulationen ermittelt werden kann. Hierzu wird der Jahreskühlenergiebedarf für einen typischen Büroraum mit unterschiedlichen Fassadentypen nach den verschiedenen Verfahren berechnet, um Unterschiede aufzuzeigen. Abschließend wird exemplarisch der Einfluss des dem jeweiligen Verfahren zugrundeliegenden Außenklimas aufgezeigt. Determining the annual cooling energy demand for office buildings using the calculation procedure according to the 2007 Building Energy Conservation Ordinance or the DIN V 18599 standard. The German Building Energy Conservation Ordinance (EnEV), which has been in force since 2007, requires a holistic balance of the energy demand for office buildings, so that for the first time energy used for cooling and electricity used for lighting must be taken into account besides energy used for thermal heat and ventilation systems. This study focuses on the annual energy consumption for cooling offices which can be determined not only according to the calculation rules laid down in the EnEV 2007 or DIN V 18599 standards but also with the aid of algorithms specified in VDI 2067 or by means of dynamic thermal simulations. Here the annual energy demand for cooling a typical office with different types of facade is calculated by means of various calculation procedures in order to highlight the differences and deduce which types of facade react particularly sensitively. An example is used to illustrate the influence of the prevailing outdoor weather conditions for each procedure. [source] Crystallization of the glycogen-binding domain of the AMP-activated protein kinase , subunit and preliminary X-ray analysisACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 1 2005Galina Polekhina AMP-activated protein kinase (AMPK) is an intracellular energy sensor that regulates metabolism in response to energy demand and supply by adjusting the ATP-generating and ATP-consuming pathways. AMPK potentially plays a critical role in diabetes and obesity as it is known to be activated by metforin and rosiglitazone, drugs used for the treatment of type II diabetes. AMPK is a heterotrimer composed of a catalytic , subunit and two regulatory subunits, , and ,. Mutations in the , subunit are known to cause glycogen accumulation, leading to cardiac arrhythmias. Recently, a functional glycogen-binding domain (GBD) has been identified in the , subunit. Here, the crystallization of GBD in the presence of ,-cyclodextrin is reported together with preliminary X-ray data analysis allowing the determination of the structure by single isomorphous replacement and threefold averaging using in-house X-ray data collected from a selenomethionine-substituted protein. [source] Irrungen und Wirrungen um Biokraftstoffe.CHEMIE IN UNSERER ZEIT (CHIUZ), Issue 5 2010Biokraftstoffe sind nicht per se nachhaltig Die jährliche Photosyntheseleistung auf der Erde übersteigt die anthropogene CO2 -Produktion. Dies legt eine energetische Nutzung der Biomasse nahe und hat die Entwicklung von Biokraftstoffen erheblich gefördert. In vielen Fällen verstößt die Nutzung von Biokraftstoffen jedoch gegen Prinzipien der Nachhaltigkeit. Für die Deckung des Weltenergiebedarfes durch Biomasse würde die gesamte verfügbare landwirtschaftliche Nutzfläche benötigt. Diese Einsicht hat eine kritische Teller-oder-Tank-Diskussion ausgelöst. Energetisch und ökologisch effizienter als die Nutzung von Biokraftstoffen wäre der Anbau schnellwachsender Hölzer und deren direkte Verstromung im Kraftwerk. Die mit großem Abstand effizienteste Nutzung der Sonnenenergie erlauben Photovoltaik und Solarthermie. Wegen ihrer hohen Energiedichte werden flüssige Biokraftstoffe der zweiten Generation aber dort, wo die Elektromobilität an Grenzen stößt, auch in Zukunft Anwendung finden. The annual photosynthesis on the Earth exceeds the anthropogenic CO2 production. This suggests an energetic use of biomass and has greatly promoted the development of biofuels. In many cases, however, the use of biofuels is breaking the rules of sustainability. To meet the world's energy demand from biomass would require the total available agricultural land. This insight has a critical plate or tank discussion triggered. Energetically and environmentally more efficient than the use of biofuels would be the cultivation of fast-growing timber and its direct use in coal power plants for electricity production. By far the most efficient use of solar energy is provided by photovoltaic and solar heat use. Because of their high energy density liquid second-generation biofuels will be applied also in future in such cases where electrical mobility has its limits. [source] Cross-talk between L-type Ca2+ channels and mitochondriaCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 2 2010Helena M Viola Summary 1. Calcium is necessary for myocardial function, including contraction and maintenance of cardiac output. Calcium is also necessary for myocardial energetics and production of ATP by mitochondria, but the mechanisms for calcium regulation by mitochondria are still not fully resolved. 2. The cytoskeleton plays an important role in maintaining a cell's integrity. It is now recognized that cytoskeletal proteins can also assist in the transmission of signals from the plasma membrane to intracellular organelles. Cytoskeletal proteins can regulate the function of the L-type Ca2+ channel and alter intracellular calcium homeostasis. 3. Recent evidence suggests that calcium influx through the L-type Ca2+ channel is sufficient to alter a number of mitochondrial functional parameters, including superoxide production, NADH production and metabolic activity, assessed as the formation of formazan from tetrazolium salt. This occurs in a calcium-dependent manner. 4. Activation of the L-type Ca2+ channel also alters mitochondrial membrane potential in a calcium-independent manner and this is assisted by movement of the auxiliary ,2 -subunit through F-actin filaments. 5. Because the L-type Ca2+ channel is the initiator of contraction, a functional coupling between the channels and mitochondria may assist in meeting myocardial energy demand on a beat-to-beat basis. [source] | |||||||||||||||||||||||||||||||||||||||||||