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Abstract An ATP-activated transhydrogenase which catalyzes the reduction of TPN + by DPNH has been demonstrated in the microsomal fraction from the endosperm of immature Echinocystis macrocarpa seeds. The activity is specifically dependent on the presence of ATP ( K m of approximately 0.1 m m ) of several nucleotides tested. The reaction is stimulated by MgCl 2 addition up to concentrations of 6 m m . When 10 −2 m EDTA is added to the assay mixture in the absence of added MgCl 2 , a transhydrogenation reaction is observed which no longer shows any dependence on added ATP. A TPN + -dependent ATPase activity can be demonstrated in these preparations, but no fixed stoichiometry between ATP cleavage and TPNH formation could be established. A lag in attaining the maximal rate of transhydrogenation is seen unless the enzyme is preincubated for 10 min with ATP before initiating the reaction. It can further be shown that preincubation of the enzyme with ATP followed by removal of the ATP on a Dowex 1 column produces an enzyme capable of catalyzing the transhydrogenation without the further addition of ATP. 2,4-Dinitrophenol and thyroxin are effective inhibitors of the transhydrogenase and 2,4-dinitrophenol was shown to inhibit the activating effect of ATP during the preincubation period. It is concluded that the role of ATP is in the modification of the enzyme rather than direct participation in the transhydrogenation. The transhydrogenase is inhibited by ADP and AMP. This results in a response of the enzyme to adenylate energy charge in a manner characteristic for regulatory enzymes which participate in ATP-utilizing metabolic sequences.

Abstract This article focuses on the results obtained by the enforcement of a original greenhouse gas emissions policy, issued in recent years in several municipalities in Northern Italy. The Municipality of Reggio Emilia was one of the firsts in Italy to develop and adopt a voluntary building energy-consumption certification method called Ecoabita, aiming to promote energy efficiency in buildings over its jurisdiction. Several reasons make this project innovative: first, the certification method has been processed through and verified by a quality international agency, secondly the procedure is assisting financial-incentive policies both on mandatory (European Directive 2002/91/CE) and voluntary basis (Municipality Protocol Ecoabita), finally it allows to obtain eligible credits for avoided emissions that can be negotiated on the CO2 exchange market. With specific reference to Reggio Emilia case, acknowledged the amount of actions, that are normally scheduled in the municipality throughout a year, it has been evaluated the benefit, in terms of environmental improvement, descended from the protocol, also projecting their trend in future years up to 2020 as well, demonstrating the scheduled interventions are fundamental in sought of the achievement of the Kyoto and Copenhagen commitments. The entire procedure has been developed in accordance to the parameters given by UNFCCC for these kinds of analyses and has been recently confirmed to be one of the most accurate international accounting procedure by a survey developed by the scientific committee of the European Project LIFE-LAKS.

This paper presents an experimental study of indoor thermal environment near a full-scale glass facade with different types of shading devices under varying climatic conditions in winter. Interior glazing and shading temperature, operative temperature and radiant temperature asymmetry were measured for facade sections with roller shades and venetian blinds at different positions. Interior glass surface temperatures can be high during sunny days with low outdoor temperature. Shading systems significantly improved operative temperature and radiant temperature asymmetry during cold sunny days, depending on their properties and tilt angle. During cloudy days the impact was smaller, however the shading layers could still decrease the amount of heat loss through the facade. A transient building thermal model, which also calculates indoor environmental indices under the presence of solar radiation, was developed and compared with the experimental measurements. Part II of this paper uses this validated model with a transient, two-node thermal comfort model (including transmitted solar radiation) for assessment of indoor environmental conditions with different building envelope and shading properties, facade location and orientation.

Patients with pure autonomic failure (PAF) and multiple system atrophy (MSA) may complain of feeling light-headed after alcohol ingestion particularly on assumption of the upright posture. The reasons for this have not been investigated. We therefore studied the effects of oral alcohol (40% vodka in sugar-free orange juice) and placebo (juice only) on the systemic and regional (including superior mesenteric artery, SMA) blood flow in nine patients with PAF and six patients with MSA. After alcohol, there was a fall in supine blood pressure (BP) and vasodilatation in the SMA but no change in cardiac output, or forearm muscle and cutaneous blood flow in either PAF or MSA; BP fell further during head-up tilt with no changes in levels of plasma catecholamines. After placebo, there were no changes while supine. We conclude that alcohol lowers supine BP and dilates the SMA with no change in muscle or cutaneous blood flow. Alcohol also enhances the fall in BP during head-up tilt. This may explain the symptoms experienced by PAF and MSA patients after alcohol.

Bioenergy is considered a sustainable substitute to fossil-fuel resources and the development of a prudent combination of renewable and innovative conversion technologies are essential for the valorization and effective conversion of biowaste to value-added commodities. Here, a negative pressure-induced carbonization process was proposed for the valorization of lignin-enriched biowaste precursor to bio-oil and environmental materials (biochar) at various temperatures. The high heating values (HHV) of the as-prepared biochars from the lignin enriched precursor under negative pressure (low-medium vacuum) were within 25.9-31.5 MJ/kg, which matched satisfactorily to the commercial charcoal. Whereas, the bio-oils produced from the lignin enriched precursor under vacuum conditions was a blend of complex aromatic and straight-chain hydro-carbons, including aldehyde, ketone, phenol, and furans, exhibiting ability as potential heating-oil with HHV within 21.2-28.2 MJ/kg. Moreover, the biochars produced under vacuum environments at higher temperature showed greater stability (22.5-35.9%) than those produced under N2 atmosphere.

Abstract As a consequence of deregulation, competition and problems in securing capital outlays for expansion of the infrastructure, modern power systems are operating at ever-smaller capacity and stability margins. Traditional entities involved in securing adequate protection and control for the system may soon become inadequate, and the emergence of the new participants (non-utility generation, transmission and distribution companies) requires coordinated approach and careful coordination of the new operating conditions. The paper reviews the key issues and design considerations for the present and new generation of SPS and emergency control schemes, and evaluates the strategies for their implementation.

Abstract The Liquefied natural gas (LNG) cryogenic submerged pump, the core power equipment for the transportation of liquefied natural gas, is prone to cavitation. However, based on the traditional analysis of the pressure drop, the irreversible loss after cavitation can barely be displayed quantitatively. To solve this problem, an entropy production diagnostic model (EPDM) by the contribution of viscous entropy production (VEP), turbulent entropy production (TEP) and wall entropy production (WEP) for the cavitation flow was established to calculate the energy loss. The cryogenic cavitation model and proposed EPDM were proved to be reliable after comparing results with Hord’s experiment in an ogive and cavitation experiment in a centrifugal pump. Then, by studying the total entropy production, it was found that the EPDM could well predict the occurrence of the critical cavitation and the deterioration of cavitation. When compared with TEP and WEP, the effect of VEP is negligible. As the cavitation area expands from the suction surface of inducer (id) to the first-stage impeller (impA), the cavitation process can be divided into three stages and the total energy loss increases significantly from the first stage to the third one. Through the global distribution of energy loss, it was found that the faster growth of the loss in the second-stage impeller (impB) and the second-stage guide vane (gvB), not in id and impA, contributes more to the energy loss after cavitation. Finally, from the variation of ratio of TEP to WEP, it reveals that cavitation has a greater effect on the WEP rate for the impB, but the turbulent viscous dissipation is still dominant, while the eddy dissipation and resistance loss in gvB with the evolution of cavitation are both crucial.

Abstract Probability density functions (PDFs) are normally used to describe wind speed distribution for the proper selection of wind turbines in a given location. The identification of a suitable PDF is fundamental for accurately assessing the wind energy potential and designing the wind farms. To achieve this objective, the use of a mixture of two truncated normal distributions (MTTND), defined for v ≥ 0 and obtained by linearly combining two normal distributions with different means and variances, is proposed in this work for the representation of the wind speed PDF. The distribution is a function of five parameters, does not require a high computational burden and allows the representation of wind calm hours (v = 0). The use of the MTTND allows an accurate estimation to be obtained of the experimental discrete distribution of the probability density and cumulative probability, and the characteristic statistical quantities used to estimate the available energy and the performance indicators in the selection of both the site and wind turbine. The validity of the use of the MTTND was verified by comparison with the most widespread PDFs in the scientific literature: Weibull, Rayleigh, lognormal, gamma, inverse Gaussian and Burr. This comparison was developed using experimental wind speed data relating to five Italian locations and a location in Colorado (USA) belonging to the National Renewable Energy Laboratory. For each location, the parameters of each PDF were obtained with the least squares non-linear regression method. The results of the comparisons, in terms of the coefficient of determination R2 and root mean square error (RMSE) for goodness of fit and in terms of relative error in the calculation of the statistical quantities, show that the use of the MTTND gives rise to greater accuracy than a conventional wind speed PDF.

A procedure for optimizing the sizes of soil heat accumulators is presented together with technical and economic solutions the use of which allows the construction cost of such facilities to be minimized. Calculation examples are given.