Valyl-transfer RNA formation stimulated by monovalent cations and spermine in rat liver

The effects of hypothalamic disconnection on body temperature and hypothalamo-pituitary-adrenal activity following acute and repeated exposures to heat were studied. Intact male rats, or animals with complete posterior or anterior hypothalamic disconnection, were exposed to a temperature of 36 degrees C and a relative humidity of 35-45%. In the complete posterior and anterior hypothalamic disconnected rats the basal Tre was higher than that of the intact rats; the rise in Tre following heat exposure was lower in the operated rats than in the intact animals. All the experimental animals, except for those with anterior hypothalamic disconnection, showed a significant inhibition of corticosterone release on exposure to heat for 30 min, but no inhibition was observed in any of the disconnected rats when they were exposed to heat for 120 min. These results suggest that the main stimulus for ACTH release, during the first 30 min of heat exposure, is mediated by a neural input through the posteroir hypothalamus and this is followed by a nerural and/or humoral mechanism which enables the animals to increase their corticosterone secretion.     

Availability analysis of a N modules parallel system with common memory,central controller and distributed software

Parallel systems with processing distributed in the various modules are very interesting examples of hardware/software tradeoffs within a complex structure. An example of such a system mode of N modules, has been considered. The implications of a common memory and a central controller are analysed and an availability model is derived.The division of the software task into subtasks is viewed as a source of possible deadlock of the structure. Series catastrophic states due to hard core units and software coupling are included in the availability analysis.     

Phenotypic and genetic diversity of enterococci isolated from Italian cheeses

In the present study, 124 enterococcal strains, isolated from traditional Italian cow, goat and buffalo cheeses, were characterized using phenotypic features and randomly amplified polymorphic DNA polymerase chain reaction (RAPD-PCR). The RAPD-PCR profiles obtained with four primers and five different amplification conditions were compared by numerical analysis and allowed an inter- and intraspecific differentiation of the isolates. Whole cell protein analysis by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was used as a reference method for species identification. The strains were identified as Enterococcus faecalis (82 strains), E. faecium (27 strains), E. durans (nine strains), E. gallinarum (four strains) and E. hirae (two strains). Species recognition by means of RAPD-PCR was in agreement with the SDS-PAGE results except for eight strains of E. faecium that clustered in separated groups. On the other hand, phenotypic identification based on carbohydrate fermentation profiles, using the rapid ID 32 STREP galleries, gave different results from SDS-PAGE in 12.1% of the cases. The majority of the strains had weak acidifying and proteolytic activities in milk. One E. faecium strain showed vanA (vancomycin resistance) genotype while four strains showed a beta-haemolytic reaction on human blood. Several strains showed antagonistic activity towards indicator strains of Listeria innocua, Clostridium tyrobutyricam and Propionibacterium freudenreichii subsp. shermanii.     

Evaluation of buffalo colostrum quality by estimation of enzyme activity levels

A study to evaluate the value and potential use of colostral enzymes as markers for the evaluation of buffalo colostrum quality was conducted. The enzymes gamma-glutamyltransferase (GGT), lactic dehydrogenase (LDH), and alkaline phosphatase (ALP) in buffalo's colostrum were measured spectrophotometrically, and their activities were correlated with the gamma-globulin content. Gamma-globulin concentration was determined following the electrophoretic separation of the colostral proteins and quantified with a densitometer. Colostrum was obtained from 15 dams, soon after calving. Means, standard deviations, correlation coefficients, and degree of significance were calculated using the general linear model procedure of the Statistical Analysis Systems program. The activity of GGT in the colostrum was the highest, followed by LDH and ALP. A significant correlation (r = 0.86; P < 0.001) was seen between GGT and gamma-globulin concentration in the colostrum, supporting the suggestion of using this enzyme as a marker for the evaluation of colostrum quality.     

On the Tolerance to Manufacturing Defects in Molecular QCA Tiles for Processing-by-wire

Among emerging technologies, Quantum-dot Cellular Automata (QCA) relies on innovative computational paradigms. For nano-scale implementation, the so-called processing-by-wire (PBW) paradigm in QCA is very effective as processing takes place, while signal communication is accomplished. This paper analyzes the defect tolerance properties of PBW for manufacturing tiles by molecular QCA cells. Based on a 3?×?3 grid and various input/output arrangements in QCA cells, different tiles are analyzed and simulated using a coherence vector engine. The functional characterization and polarization level of these tiles for undeposited cell defects are reported and detailed profiles are provided. It is shown that novel features of PBW are possible due to the spatial redundancy of the cells in the tiles that permits to retain at high probability the fault free function in the presence of defects. Moreover, it is shown that QCA tiles are robust and inherently tolerant to cell defects (by logic equivalence, also additional cell defects can be accommodated).     

Dissimilar Resistance Spot Welding of Q&P and TWIP Steel Sheets

Dissimilar resistance spot welding of twinning induced plasticity (TWIP) and quenching and partitioning (Q&P) steel grades has been investigated by evaluating the effects of clamping force, welding current, and welding time on the microstructure, shear tension strength, and fracture of welded samples. The spot welding of TWIP and Q&P steels promotes the occurrence of an asymmetrical weld nugget with a greater dilution of TWIP steel because of its lower melting temperature and thermal conductivity. As a result, weld nuggets exhibit an austenitic microstructure. TWIP steel undergoes a grain coarsening in the HAZ, whereas Q&P steel undergoes some phase transformations. Welded samples tend to exhibit higher shear tension strength as they are joined at the highest welding current, even though an improper clamping force can promote excessive metal expulsion, thereby reducing the mechanical strength of the welded joints. Shear tension welded samples failed through interfacial fracture with partial thickness fracture mode for a low welding current, while partial thickness with button pull fractures were observed when a high welding current was used. The weld spots predominantly failed at the TWIP side. However, as TWIP steel can work harden significantly in the more resistant welded joints, the failures occur, instead, at the Q&P side.     

Dynamic Galois Theory

Given a separable polynomial over a field, every maximal idempotent of its splitting algebra defines a representation of its splitting field. Nevertheless such an idempotent is not computable when dealing with a computable field if this field has no factorization algorithm for separable polynomials. Moreover, even when such an algorithm does exist, it is often too heavy. So we suggest to address the problem with the philosophy of lazy evaluation: make only computations needed for precise results, without trying to obtain a priori complete information about the situation. In our setting, even if the splitting field is not computable as a static object, it is always computable as a dynamic one. The Galois group has a very important role in order to understand the unavoidable ambiguity of the splitting field, and this is even more important when dealing with the splitting field as a dynamic object. So it is not astonishing that successive approximations to the Galois group (which is again a dynamic object) are a good tool for improving our computations. Our work can be seen as a Galois version of the Computer Algebra software D5 ( Della Dora et al., 1985).     

State of the art and prospects of Italian biogas production from animal sewage: Technical-economic considerations

In the last few years, the recent regulations of the Energy and Environment Policy of the European Union (EU) Energy Policy, together with the new Common Agricultural Policy (CAP) have been aiming to increase the integration of renewable resources, and in particular of biogas, into the EU energy system thanks to the adoption of new tools for their promotion. The production of biogas from animal waste, both on a European and national level, still represents only a small percentage of the total amount deriving from anaerobic digestion of organic matter. In this context, it was deemed opportune to evaluate the state of the art in the use of biogas in Italy and its production potential, with regard to animal sewage, in the light of the current technical-economic and legislative obstacles.     

Healing assessment of tile sets for error tolerance in DNA self-assembly

An assessment of the effectiveness of healing for error tolerance in DNA self-assembly tile sets for algorithmic/nano-manufacturing applications is presented. Initially, the conditions for correct binding of a tile to an existing aggregate are analysed using a Markovian approach; based on this analysis, it is proved that correct aggregation (as identified with a so-called ideal tile set) is not always met for the existing tile sets for nano-manufacturing. A metric for assessing tile sets for healing by utilising punctures is proposed. Tile sets are investigated and assessed with respect to features such as error (mismatched tile) movement, punctured area and bond types. Subsequently, it is shown that the proposed metric can comprehensively assess the healing effectiveness of a puncture type for a tile set and its capability to attain error tolerance for the desired pattern. Extensive simulation results are provided.     

Heat transfer in forced cooled cables

A calculation method is presented for continuous rating of cable lines. The method takes into account the actual environment conditions, such as different types of soil, change of geometrical disposition, etc. This method is based on the resolution in terms of limit differences. The results for a full-scale experimental installation were used to check the theoretical model. Comparison between the measured and calculated rises showed a difference of 5% in general and a maximum of 7%, which may be considered acceptable for line design