Transport Properties of K_xV_2O_5·nH_2O Nanocrystalline Films

Five different compositions of K x V 2 O 5 ·nH 2 O(where x=0.00,0.0017,0.0049,0.0064 and 0.0091 mol) were prepared by the sol-gel process.Electrical conductivity and thermoelectric power were measured parallel to the substrate surface in the temperature range of 300-480 K.The electrical conductivity showed that all samples were semiconductors and that conductivity increased with increasing K content.The conductivity of the present system was primarily determined by hopping carrier mobility.The carrier density was evaluated as well.The conduction was confirmed to obey non-adiabatic small polaron hopping.The thermoelectric power or Seebeck effect,increased with increasing K ions content.The results obtained indicated that an n-type semiconducting behavior within the temperature range was investigated.     

Heating and cooling energy demand and related emissions of the German residential building stock under climate change

The housing sector is a major consumer of energy. Studies on the future energy demand under climate change which also take into account future changes of the building stock, renovation measures and heating systems are still lacking. We provide the first analysis of the combined effect of these four influencing factors on the future energy demand for room conditioning of residential buildings and resulting greenhouse gas (GHG) emissions in Germany until 2060. We show that the heating energy demand will decrease substantially in the future. This shift will mainly depend on the number of renovated buildings and climate change scenarios and only slightly on demographic changes. The future cooling energy demand will remain low in the future unless the amount of air conditioners strongly increases. As a strong change in the German energy mix is not expected, the future GHG emissions caused by heating will mainly depend on the energy demand for future heating.     

Maximal functional capacity in patients with endomyocardial fibrosis

We evaluated objectively the cardiocirculatory dysfunction of patients with EMF, and related the functional class (FC-NYHA) to the data obtained by analysis of maximal functional capacity. We studied 55 subjects, divided into three groups: group 1 (G1) 21 (38.1%) normal persons, group 2 (G2) seven (12.7%) patients with EMF who were in FC I or II, and group 3 (G3) 27 (49%) patients in FC III or IV. Maximal oxygen consumption (VO2max) and O2 pulse index (PO2max) were obtained using a Beckman computerized gas analyser. The mean values were significantly different among the three groups. We conclude that the greater the clinical impairment, the greater the alterations that occur in the indices of cardiac function.     

Photodecomposition of Bil3 films

The effect of illumination on the transmittance and the structure of Bil₃ films was investigated. Photoexcitation was found to induce structural variation and decomposition of the films into metallic bismuth and free iodine. Moreover, measurements of the electrical conductivity during heating show thermal decomposition of the films and it was found that the temperature of decomposition depends on the thickness of the film.     

Crossflow microfiltration for the cold stabilization of roselle (Hibiscus sabdariffa L.) extract

In this study, roselle extract was cold sterilized by crossflow microfiltration. At laboratory scale the optimal operating conditions at volumetric reduction ratio (VRR) 1 cannot be generalized when VRR is greater than 1. Indeed, at VRR 1 the optimal transmembrane pressure was 2.5 bar with a permeate flux of 185 L h⁻¹ m⁻², while at VRR 20 optimal pressure was 3.7 bar with a permeate flux of 95 L h⁻¹ m⁻². A simple model that allowed to represent the effect of VRR and transmembrane pressure on the permeate flux was adjusted with the experiments done at laboratory scale. This model used to predict the permeate flux using a semi-industrial pilot scale equipment gave a good match between the experimental and calculated performances. Permeate was collected aseptically and stored at 4, 20 and 37 °C for 90 days. A roselle extract storage at 4 and 20 °C was appropriate for consumption after a 3 month shelf life.     

Directed Modulation of Protein Kinase C Isozyme Selectivity with Bisubstrate‐Based Inhibitors

Kinases present an attractive target for drug development, since they are involved in vital cellular processes and are implicated in a variety of diseases, such as cancer and diabetes. However, obtaining selectivity for a specific kinase over others is difficult since many current kinase inhibitors exclusively target the highly conserved kinase ATP binding domain. Previously, a microarray‐based strategy to discover so‐called bisubstrate‐based inhibitors that target the more specific peptide binding groove in addition to the ATP binding site was described. One attractive feature of this strategy is the opportunity to tune the selectivity of these inhibitors by systematically varying components. In an extension to this previous work, this study explores the potential of this guided selectivity modulation, leading to a series of inhibitors with different selectivity profiles against highly homologous protein kinase C (PKC) isozymes. Of the inhibitors studied, most exhibited improved potency and selectivity compared with their constituent parts. Furthermore, the selectivity was found to be tunable either through modification of the pseudosubstrate peptide (peptide binding groove) or the ATP‐competitive part (ATP binding site). In a number of cases, the selectivity of the construct could be predicted from the initial peptide substrate profiling experiment. Since this strategy is applicable to all kinase sets, it could be used to rapidly develop uniquely selective inhibitors.     

Selecting ultrafiltration and nanofiltration membranes to concentrate anthocyanins from roselle extract (Hibiscus sabdariffa L.)

Ten nanofiltration flat-sheet membranes and eight tight ultrafiltration membranes with nominal MWCOs ranging from 0.2 to 150 kDa were tested to concentrate anthocyanin extract from roselle. A pilot system was used, which featured a membrane cell with an effective area of 0.0155 m². Permeate fluxes were recorded for transmembrane pressures between 0.5 and 3.0 MPa, while keeping all other operating conditions constant (volumetric reduction ratio 1, 35 °C). Retention values of total soluble solids, acidity and anthocyanins increased with transmembrane pressure. With similar permeate fluxes at average transmembrane pressure, retention of anthocyanins is significantly higher for nanofiltration membranes than for ultrafiltration membranes. A membrane was then selected for an industrial trial on the basis of its flux, retention of compounds of interest and energy consumption per liter of permeate. The trial using a 2.5-m² filtration surface, could concentrate roselle extract from 4 to 25 g total soluble solids per 100 g, with 100% retention of anthocyanins. No significant damages were observed when comparing concentrate quality with the initial roselle extract.     

The quality of orange juice processed by coupling crossflow microfiltration and osmotic evaporation

Crossflow microfiltration (CFM) and osmotic evaporation (OE) were implemented on a semi‐industrial pilot scale to obtain clarified orange juice concentrates at 450 and 620 g kg^?1 of total soluble solids. The characteristics of the juice were then assessed and compared with fresh juice and commercial concentrates. With CFM, most aroma compounds and vitamin C remained in the permeate while the more apolar compounds such as terpenic hydrocarbons and carotenoids were strongly retained by the membrane. With OE, significant losses of vitamin C and aroma compounds occurred at first, with losses progressively decreasing during treatment. Pre‐conditioning the membrane and cold regeneration of the brine reduced losses drastically, with the aroma composition tending towards that of the initial juice. The quality of pulp, a blend of the CFM retentate and OE concentrate, was high and much closer to that of the initial fresh juice than to the commercial thermal concentrate.