Chlamydophila pecorum in fetuses of mediterranean buffalo (bubalus bubalis) bred in Italy

In order to study the role played by the different species of Chlamydophila in causing abortions in Mediterranean buffalo, the Authors examined 164 fetuses from 80 different buffalo herds in Southern Italy. Three fetuses, came from two different herds, were positive. Our study confirms the pathogenic role of C. pecorum in buffalo, not only as a cause of neuropathology in calves but as an infectious abortive agent

Enhancement of Bacillus thuringiensis toxicity by feeding Spodoptera littoralis larvae with bacteria expressing immune suppressive dsRNA

n/

Experimental analysis of the performance of fractal stirrers for impinging jets heat transfer enhancement

Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.A new passive method for the heat transfer enhancement of circular impinging jets is proposed and tested. The method is based on enhancing the mainstream turbulence of impinging jets using square fractal grids, i.e. a grid with a square pattern repeated at increasingly smaller scales. Fractal grids can generate much higher turbulence intensity than regular grids under the same inflow conditions and with similar blockage ratio, at the expense of a slightly larger pressure drop. An experimental investigation on the heat transfer enhancement achieved by impinging jets with fractal turbulence promoters is carried out. The heated-thin foil technique is implemented to measure the spatial distribution of the Nusselt number on the target plate. The heat transfer rates of impinging jets with a regular grid and a fractal grid insert are compared to that of a jet without any turbulator under the same condition of power input. A parametric study on the effect of the Reynolds number, the nozzle-to-plate distance and the position of the insert within the nozzle is carried out. The results show that a fractal turbulence promoter can provide a significant heat transfer enhancement for relatively small nozzle-to-plate separation (at distance equal to 2 diameters 63% increase with respect to the circular jet at the stagnation point, and 25% if averaged over an area of radius equal to 1 nozzle diameter; respectively, against 9% and 6% of the regular grid in the same conditions of power input).dc201

Laser Marking of Titanium Coating for Aerospace Applications

Abstract In the aerospace industry, in order to ensure the identification and the traceability of the products, high repeatability, non-invasive and durable marking processes are required. Laser marking is one of the most advanced marking technologies. Compared to traditional marking processes, like punches, microdot, scribing or electric discharge pencil etcher, laser marking offers several advantages, such us: non-contact working, high repeatability, high scanning speed, mark width comparable to the laser spot dimension, high flexibility and high automation of the process itself. In order to assure the mark visibility for the component lifetime, an appropriate depth of the mark is required. In this way, a stable behaviour is ensured also when the component operates in aggressive environments (i.e. in presence of oxidation, corrosion and wear phenomena). The mark depth is strongly affected by the laser source kind and by the process parameters, such us average power, pulse frequency and scanning speed. Moreover, an excessive mark penetration could cause stress concentrations and reduce the fatigue life of the component. Consequently, an appropriate selection of the process parameters is required in order to assure visibility and to avoid excessive damage. Cold Spray Deposition (CSD) is a relative new technology that allows to produce surface coatings without significant substrate temperature increasing. In aeronautics fields this technology is useful to coat materials sensible to temperature, such as solution tempered aluminum alloy, with a titanium layer. Aim of the work is to characterize the laser marking process on CSD Ti coating, in order to study the influence of the laser marking process parameters (pulse power and scanning speed), on the groove geometry of the marking. The experimental marking tests were carried out through a 30 W MOPA Q-Switched Yb:YAG fibre laser; under different process conditions. The groove geometry was measured through a HIROX HK9700 optical microscope. The results showed the effectiveness of the laser process to produce high quality marks on the titanium layer. Moreover, a correlation between the process parameters and the mark's geometry was clearly observed

A hybrid approach of anfis—artificial bee colony algorithm for intelligent modeling and optimization of plasma arc cutting on monel™ 400 alloy

This paper focusses on a hybrid approach based on genetic algorithm (GA) and an adaptive neuro fuzzy inference system (ANFIS) for modeling the correlation between plasma arc cutting (PAC) parameters and the response characteristics of machined Monel 400 alloy sheets. PAC experiments are performed based on box-behnken design methodology by considering cutting speed, gas pressure, arc current, and stand-off distance as input parameters, and surface roughness (Ra), kerf width (kw), and micro hardness (mh) as response characteristics. GA is efficaciously utilized as the training algorithm to optimize the ANFIS parameters. The training, testing errors, and statistical validation parameter results indicated that the ANFIS learned by GA outperforms in the forecasting of PAC responses compared with the results of multiple linear regression models. Besides that, to obtain the optimal combination PAC parameters, multi-response optimization was performed using a trained ANFIS network coupled with an artificial bee colony algorithm (ABC). The superlative responses, such as Ra of 1.5387 µm, kw of 1.2034 mm, and mh of 176.08, are used to forecast the optimum cutting conditions, such as a cutting speed of 2330.39 mm/min, gas pressure of 3.84 bar, arc current of 45 A, and stand-off distance of 2.01 mm, respectively. Furthermore, the ABC predicted results are validated by conducting confirmatory experiments, and it was found that the error between the predicted and the actual results are lower than 6.38%, indicating the adoptability of the proposed ABC in optimizing real-world complex machining processes

Saldatura in configurazione testa a testa di lamiere in lega 2198 T3 mediante procedimento friction stir welding

Scopo del presente lavoro è lo studio della saldabilità mediante processo friction stir welding (FSW) di lamierein lega innovativa alluminio-litio AA 2198 T3 in configurazione di testa. In particolare, mediante tecnichestatistiche, la velocità d’avanzamento e quella di rotazione sono state messe in relazione con le proprietàmeccaniche del giunto ed è stato sviluppato un modello empirico di previsione delle suddette caratteristiche alvariare dei parametri di processo. Per lo sviluppo di questo modello, è stato utilizzato un piano fattorialecompleto 32 avente come risposte osservate la resistenza allo snervamento e la resistenza a rottura dei giunti.Il modello sviluppato può essere utilizzato per prevedere le proprietà meccaniche dei giunti con un livello diconfidenza pari al 95%. Inoltre, usando la funzione di desiderabilità (desirability function, DF) sono statitrovati i parametri di processo che massimizzano in maniera bilanciata la resistenza allo snervamento equella alla trazione. Infine, i giunti ottenuti utilizzando i parametri di processo ottimi sono stati sottoposti aprove di fatica e di tensocorrosione al fine di valutarne il potenziale utilizzo nel settore aeronautico. I risultatiottenuti mostrano che i giunti ottenuti tramite questa tecnologia hanno una buona resistenza allatensocorrosione ed un’ottima vita a fatica, paragonabile a quella del materiale base e superiore a quella disaldature ottenute con tecniche tradizionali, come TIG e MIG

Evolution of an insect immune barrier through horizontal gene transfer mediated by a parasitic wasp.

Genome sequencing data have recently demonstrated that eukaryote evolution has been remarkably influenced by the acquisition of a large number of genes by horizontal gene transfer (HGT) across different kingdoms. However, in depth-studies on the physiological traits conferred by these accidental DNA acquisitions are largely lacking. Here we elucidate the functional role of Sl gasmin, a gene of a symbiotic virus of a parasitic wasp that has been transferred to an ancestor of the moth species Spodoptera littoralis and domesticated. This gene is highly expressed in circulating immune cells (haemocytes) of larval stages, where its transcription is rapidly boosted by injection of microorganisms into the body cavity. RNAi silencing of Sl gasmin generates a phenotype characterized by a precocious suppression of phagocytic activity by haemocytes, which is rescued when these immune cells are incubated in plasma samples of control larvae, containing high levels of the encoded protein. Proteomic analysis demonstrates that the protein Sl gasmin is released by haemocytes into the haemolymph, where it opsonizes the invading bacteria to promote their phagocytosis, both in vitro and in vivo. Our results show that important physiological traits do not necessarily originate from evolution of pre-existing genes, but can be acquired by HGT events, through unique pathways of symbiotic evolution. These findings indicate that insects can paradoxically acquire selective advantages with the help of their natural enemies

New Lipidomic Approaches in Cystic Fibrosis

Lipid analysis has been a crucial source of information in cystic fibrosis (CF). New methodologies for qualitative and quantitative lipidomics allow evaluation of a large number of samples, of special interest in patient screening for diagnostic and prognostic biological markers, as well as in cell physiology. In this chapter, two new complementary approaches are described: matrix-assisted laser desorption coupled to time of flight (MALDI-TOF-ClinProTools™) and liquid chromatography coupled to ion trap mass spectrometry (LC-MS( n )). MALDI-TOF-ClinProTools™ offers a large unbiased screening for the discovery of potential lipid alterations in diseased patients. LC-MS( n ) represents a state-of-the-art lipidomic tool for the identification and quantification of such alterations. The combination of both may open new perspectives in the quest for lipids participating in CF pathogenesis, therapy targets, and biomarkers