General model to build awnings and external walls with optimum shading interaction

A general model is proposed to optimize the shading interaction between an awning and an external wall that project shadows on the facade of a construction. The original method was presented by the authors in Renewable Energy 28 (2003): 111, for a particular shading proposal. They emphasize the advantage of a one-dimensional approach to solve the problem of this interaction, analyzing the shadows projected by these elements from a side view. The generalized method, presented in this paper, is useful for architects to design shelter projects with more alternatives in the use of such shading devices. The general model also permits study and evaluation of any strategy chosen by the builder to shadow a facade, with an emphasis on windowpane shading, through graphical outputs of the solar performance.     

Determining suitability of a fly ash for silica extraction and zeolite synthesis

Zeolitic material is obtained from fly ash both by direct conversion of the ash or from SiO₂ extracts obtained from fly ash. This study focuses on determining the suitability of a fly ash for SiO₂ extraction and for zeolite synthesis by direct conversion. The SiO₂ extraction experiments from different fly ashes show that the main parameters governing the SiO₂ extraction are: (a) a high bulk SiO₂ content (>52%, for obtaining an extraction yield of 100 g SiO₂ kg^?1) in the starting fly ash, (b) a high proportion (>55%) of the bulk SiO₂ present in the degradable glass matrix and the highly soluble opaline fraction, and (c) a high bulk SiO₂/Al₂O₃ ratio (>2.0) of the fly ash. The results from experiments of zeolite synthesis by direct conversion demonstrate that the most important criteria for the selection of a fly ash for this process are: (a) a high content of Al₂O₃ and SiO₂(>65%) (b) a high glass content (>63%) and (c) relatively low SiO₂/Al₂O₃ ratio (<2.0). Multivariate analysis confirms the importance of the above‐mentioned variables and shows some additional variables that have influence on ash behaviour under alkaline conditions. It quantifies the use of those variables for determining the suitability of ashes for SiO₂ extraction and zeolite synthesis and is able to distinguish between the two. Copyright © 2004 Society of Chemical Industry     

Differential production of IL-10 by T cells and monocytes of HIV-infected individuals: association of IL-10 production with CD28-mediated immune responsiveness

The present study determines the proportions of unmyelinated cutaneous axons at the dermal-epidermal junction in glabrous skin and of myelinated and unmyelinated axons in the sural and medial plantar nerves that immunostain for subunits of the ionotropic glutamate receptors. Approximately 20% of the unmyelinated cutaneous axon profiles at the dermal-epidermal junction immunostain for either N-methyl-D-aspartate (NMDA), alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), or kainate receptor subunits. These findings are consistent with previous observations that NMDA and non-NMDA antagonists ameliorate nociceptive behaviors that result from noxious peripheral stimulation. In the sural nerve, where the large majority of myelinated fibers are sensory, approximately half of the myelinated axon profiles immunostain for the NMDA receptor 1 (R1) subunit, 28% immunostain for the glutamate receptor 1 (GluR1) AMPA subunit, and 11% for the GluR5,6,7 kainate subunits. Even higher proportions immunostain for these receptors in the medial plantar nerve, a mixed sensory and motor nerve. In the sural nerve, 20% of the unmyelinated axon profiles immunostain for NMDAR1 and only 7% label for GluR1 or GluR5,6,7. Because the sural nerve innervates hairy skin, these data suggest that glutamate will activate a higher proportion of unmyelinated axons in glabrous skin than in hairy skin. Measurements of fiber diameters indicate that all sizes of myelinated axon profiles, including Adelta and Abeta, are positively labeled for the ionotropic receptors. The presence of glutamate receptors on large-diameter myelinated axons suggests that these mechanosensitive receptors, presumably transducing touch and pressure, may also respond to local glutamate and thus be chemosensitive.     

Residual effect of atomised water vapour treatment on carbohydrate metabolism during ripening of cv “Fino de Jete” cherimoya fruit

Atomised hot water vapour at between 46 and 54 °C for 60 min was tested as a method of delaying ripening and extending shelf life in cv “Fino de Jete” cherimoya fruit (Annona cherimola Mill.). Heat treatment at 46 °C stimulated the respiration rate and starch degradation, induced ethylene production, increased the accumulation of soluble sugars and α-amylase activity, and moved the onset of ethylene production (OEP) forward. Treatment at 50 °C, and especially at 52 °C, delayed the climacteric peak and the OEP, decreased sugar and organic acid accumulation, and reduced α-amylase and invertase activity. The results obtained indicate that temperatures higher than 48 °C slowed physiological processes and carbohydrate metabolism and extend the shelf life of the cherimoya fruits, while temperatures higher than 52 °C blocked ripening irreversibly.     

Use of Water as a Solvent in Directing Hydrogenation Reactions of Aromatic Acids over Pd/carbon Nanofibre Catalysts

By conducting the catalytic hydrogenation over water miscible Pd/carbon nanofibre catalysts, selective ring hydrogenation of aromatic acids can be performed in aqueous solution without the need to provide protection for the external acid function.     

Computer method for kinematic analysis of lower-pair mechanisms—II position problemsEine neue methode zur analyse von mechanismen teil 2: Positionsprobleme

In the first part of this study, a new method for solving the problem of kinematic analysis was presented, based on the concepts of “basic coordinates” and “link constraint equations”. In this second part, these same concepts are used to solve the problems of initial position, finite displacements and static equilibrium position of a mechanism with springs between its links. The proposed algorithms are elementary in their formulation and of exceptional efficiency in their performance. The methods describes are based on the solution of a problem of mathematical programming. Several examples are presented, giving an idea of the potential of said algorithms.     

Multiphase precipitation of carbides in Fe-C system: Part II. Model based on kinetics of complex reactions

The precipitation of carbides in the Fe-C system aged at constant temperature is simulated considering two transformation kernels of complex reactions, involving different impingement and rate-time factors. The metastable and stable phase are identified by deconvolution of the experimental kinetics. The activation energy of carbides is found to depend, slightly, on the transformation kernel in which it is used.     

Mechanisms of the hypoglycemic effects of the alpha2-adrenoceptor antagonists SL84.0418 and deriglidole

The effects of the alpha2-adrenoceptor antagonist SL84.0418 and its two enantiomers, (+) deriglidole and (-)SL86.0714 on glucose and insulin levels were examined in mice and in neonatal streptozotocin-induced diabetic rats. It was recently demonstrated in mouse pancreatic beta-cells that both deriglidole and SL86.0714 inhibit ATP-sensitive K+ channel with similar potency whereas alpha2-adrenoceptors are blocked only by deriglidole. In the present study, we showed, in vivo in mice, that SL84.0418 and deriglidole potently reduced glycemia and antagonized diazoxide-induced hyperglycemia, whereas SL86.0714 and tolbutamide were markedly less potent. In diabetic rats, SL84.0418 and deriglidole (10 mg/kg i.p.) fully normalized glucose tolerance whereas SL86.0714 and tolbutamide only slightly improved it. Five min after deriglidole administration in mice a marked and short lasting rise in insulin levels was observed, followed by a progressive reduction of glycemia. In diabetic rats, insulin and norepinephrine levels rose 15 min after deriglidole administration. Sympathetic outflow blockade by chlorisondamine, beta-adrenoceptor blockade by propranolol or their combination markedly reduced deriglidole-induced rise in insulin levels in a similar manner. Furthermore, in chlorisondamine-treated animals norepinephrine levels were strongly lowered and not modified by deriglidole and propranolol administration. However, in spite of sympathetic outflow and beta-adrenoceptor blockade, a moderate rise in insulinemia was still observed after deriglidole administration. Taken together these data demonstrate that deriglidole is the enantiomer that mediates the antihyperglycemic and insulin secretory effects of SL84.0418. Our study suggests that the major part of deriglidole effects is the consequence of the blockade of prejunctional alpha2-adrenoceptors that have reinforced the release of catecholamines in adrenergic nerve endings and indirectly activated postjunctional beta-adrenoceptors to further potentiate insulin secretion. However, it is also suggested that another undefined mechanism is involved in deriglidole potentiation of insulin secretion.     

Automatic calibration for on-line process monitoring in continuous-flow systems

An automatic procedure for calibration in continuous-flow systems is proposed. A flow gradient unit in the sample channel, controlled via a switching valve, delivers a concentration gradient of the standard so that the standard concentration varies with time after the flow-rate gradient is started. Thus, the signal (absorbance)- concentration relationship can be determined and checked for (recalibration) as frequently as required. The procedure was applied to a simulated continuous monitoring of hydrazine in waters, as well as to specific water samples that were spiked with hydrazine at different concentrations.