The ontogenesis of the alimentary tract and its associated structures (liver, pancreas, gall bladder) was studied histologically in common pandora from hatching (0 DAH, days after hatching) until day ...50 (50 DAH). Larvae were obtained by natural spawning from a broodstock adapted to captivity. They were stocked in 1500 l tanks supplied with
Isochrysis galbana and
Tetraselmis suecica from hatching until the
Artemia feeding stage, at a temperature of 18.5–20 °C. Larvae were fed Selco-enriched
Brachionus plicatilis from day 3,
Artemia nauplii from day 28 and formulated feed from day 35. At hatching, the digestive tract was a histologically undifferentiated straight tube lying dorsally to the yolk sac. At first feeding (3–4 DAH) both the mouth and anus had opened and the digestive tract was differentiated into four portions: buccopharynx, oesophagus, incipient stomach and intestine. The pancreas, liver and gall bladder were also differentiated at this stage. Within 2 days after the commencement of exogenous feeding, the anterior intestinal epithelium showed large vacuoles indicating the capacity for absorption of lipids, whereas supranuclear ninhydrin-Schiff (NS) positive inclusions indicating protein absorption were observed in the posterior intestinal epithelium. Both the bile and main pancreatic ducts had opened in the anterior intestine, just after the pyloric sphincter, at this stage. Intestinal coiling was apparent since 4 DAH, while mucosal folding began at 10 DAH. Scattered PAS-positive mucous cells occurred in the oral cavity and the intestine, while they were largely diffused in the oesophagus. Gastric glands and pyloric caeca appeared at 28 DAH, indicating the transition from larval to juvenile stage and the acquisition of an adult mode of digestion.
In this paper, the short-term scheduling optimization of a combined cycle power plant is accomplished by exploiting hybrid systems, i.e., systems evolving according to continuous dynamics, discrete ...dynamics, and logic rules. Discrete features of a power plant are, for instance, the possibility of turning on/off the turbines, operating constraints like minimum up and down times and the different types of start up of the turbines. On the other hand, features with continuous dynamics are power and steam output, the corresponding fuel consumption, etc. The union of these properties characterize the hybrid behavior of a combined cycle power plant. In order to model both the continuous/discrete dynamics and the switching between different operating conditions, we use the framework of mixed logic dynamical (MLD) systems. Then, we recast the economic optimization problem as a model predictive control (MPC) problem, that allows us to optimize the plant operations by taking into account the time variability of both prices and electricity/steam demands. Because of the presence of integer variables, the MPC scheme is formulated as a mixed integer linear program that can be solved in an efficient way via dedicated software.
Modern experiments for the search of extremely rare processes require high resolutions (order of 50–200keV/c) tracking systems for particle momenta in the range of 50–300MeV/c, dominated by multiple ...scattering contributions. We will present a newly developed construction technique for ultra-low mass Drift Chambers fulfilling this goal. It consists of (1) a semiautomatic wiring machine with a high degree of control over wire mechanical tensioning (better than 0.2g) and over wire positioning (of the order of 20μm) for simultaneous wiring of multi-wire layers; (2) a contact-less IR laser soldering tool designed for a feed-through-less wire anchoring system; (3) an automatic handling system for storing and transporting the multi-wire layers to be placed over the drift chamber end-plates. These techniques have been successfully implemented at INFN-Lecce and University of Salento and are currently being used for the construction of Drift Chamber of the MEG (μ→eγ) upgrade experiment.
This study reports the monitoring of several emerging viral pathogens in Mauritania, which was carried out by the analysis of bovine and camel samples taken at the slaughterhouse of Nouakchott. Blood ...and serum were collected by random sampling from 159 camels and 118 cattle in March 2013 at the large animals abattoir in Nouakchott. Serological tests for Rift Valley Fever (RVF), Peste des Petits Ruminants (PPR), West Nile disease (WND), epizootic haemorrhagic disease (EHD) and African horse sickness (AHS) were carried out using commercial ELISA kits. The samples, which resulted positives for PPR, WND and AHS, were tested with the confirmatory virus neutralization test (VNT). According to ELISA results, serological prevalence of RVF was 45% (95% CI 52.3–37.7) in camels and 16% (95% CI 22.6–9.4) in cattle. The difference between the observed prevalences in camels and in cattle was significant (
p
value ≤ 0.01). PPR was absent in camels and had 12% prevalence (95% CI, 17.86–6.14) in cattle. Furthermore, camels showed 92% (95% CI, 96.1–87.9) prevalence of WNV, 73% (95% CI, 82.3–63.64) of EHD and 3% (95% CI, 5.6–0.4) of AHS. This data are of relevance since provided useful feedbacks on the circulation of the pathogens in field. Moreover, this survey provided new information on the susceptibility of camels to several emerging pathogens and on the possible use of this species as sentinel animal.
West Nile virus (WNV) circulation dynamics in the context of the urban environment is not yet elucidated. In this perspective, three groups of eight rock pigeons (Columbia livia) were inoculated with ...three WNV lineage 1 strains isolated in Italy between 2009 and 2012. The pigeons did not develop any clinical signs consistent with WNV acute infection. All animals seroconverted and shed virus up to 15 days post-infection by the oral or cloacal routes. In all infected groups viraemia lasted for 4 days post-infection. No WNV-specific gross or histological lesions were found in infected birds compared to control birds and immunohistochemistry remained constantly negative from all tissues. The reservoir competence index was also assessed and it ranged between 0·11 and 0·14. This study demonstrates that pigeons are competent reservoir hosts for Italian WNV lineage 1 circulating strains thus potentially posing a risk to the public health system.
In dairy cows, the intensity of metabolic activity, associated with the negative energy balance (NEBAL), is responsible for an increased production of reactive oxygen species (ROS) and, subsequently, ...for the development of the condition of oxidative stress, which may overwhelm the antioxidant potential of the bovine maternal organism, making it prone to the development of many puerperal dysfunctions, as well as to an alteration of colostrum and milk quality. Given these premises, the aims of this study are to evaluate serum and milk concentrations of ROS and lipoperoxides, vitamins A and E, on the 10th, 12th, 14th and 16th day postpartum of dairy cows, a particularly critical period during which the NEBAL reaches its nadir, and to compare the trends of these parameters in two different bovine breeds. The study was performed in pluriparous Italian Friesian and Brown dairy cows. On the 10th day postpartum, all cows underwent a clinical examination to exclude the presence of alterations; furthermore, on the same day, a milk sample was collected from each cow, in order to perform the somatic cell count (SCC; (CE) N. 853/2004) and to establish which of them had an SCC ⩽400 000/ml or >400 000/ml. In this study, among the 110 cows that were initially selected, the evaluation of these parameters allowed the inclusion of 80 animals, which were divided into four groups of 20 subjects each: Group F and F1: Italian Friesian healthy cows, with SCC ⩽400 000/ml and >400 000/ml, respectively; Group B and B1: Italian Brown healthy cows, with SCC ⩽400 000/ml and >400 000/ml, respectively. On the 10th, 12th, 14th and 16th day postpartum, peripheral blood and milk samples were collected. The results obtained show that in group B1 there were higher concentrations of ROS and milk antioxidants compared with Friesian group cows. This datum let us suppose that even in the presence of higher ROS concentrations the antioxidant status found in group B1 seems to be able to counteract the oxidative damage, which is more likely to develop in these cows.
The Gonadotropin-Releasing Hormone (GnRH) exists in two isoforms, GnRH-I and GnRH-II, in most vertebrates, including humans. Both of these isoforms and their respective receptors have been found in ...many healthy and pathologic extra nervous system tissues, such as cells found in cancers of the reproductive systems and, in particular, in breast cancer. GnRH analogues are used as therapeutic agents in the case of sex-hormone-dependent tumours. Besides acting as suppressors of steroidogenesis, GnRH analogues seem to interfere with mitogenic signal transduction pathways, thus behaving as negative regulators of tumour growth and progression. GnRH analogues counteract the proliferating effects of both epidermal growth factor (EGF) and insulin like growth factor (IGF-I); additionally, it affects the mitogen-activated protein kinase (MAPK) cascade and modulates the activity of the urokinase-type plasminogen activator (uPA)/plasminogen activator inhibitory (PAI) system, which is involved in the process of metastasis. In addition, GnRH analogues decrease the expression of many growth factors involved in the development of human uterine myomas (as well as endometriotic tissue), such as the vascular endothelial growth factor (VEGF), which is deeply implied in the angiogenesis of many benign and malignant tumours, including breast cancer. Angiogenesis is one of the primary processes leading to the progression and metastasis of breast cancer cells, and a key therapeutic goal in the fight against tumours is the blocking of new vessel sprouts. Given these premises, this review provides an update on the background of anti-neoplastic properties of GnRH analogues..
Small foci of myocarditis (Fig. 2), mainly characterized by lymphocytes infiltrating the interstitial connective tissue, were detected in 4/24 WNV-infected animals (one in group A and three in group ...C).
Aquaculture of sea bass is widely spread in the Mediterranean and employs a variety of husbandry protocols that need to be evaluated in terms of fish well-being. Behavioural tests can be used as ...operational indicators of short-term stress, because changes in swimming performance and/or muscle activity (e.g. electromyograms) can be interpreted as response associated with a wide variety of stressors. Diagnostic procedures, based on physiological telemetry, will thus enable appropriate mitigative strategies to be implemented to ensure the well-being of cultured fish. The objective of this study was to examine the contribution of two muscle types to the swimming activity of sea bass (Dicentrarchus labrax, L. 1758). Hard-wire technology was used to 'fine-tune' measures obtained using a physiological transmitter. Fine-tuning showed that the aerobic muscle displayed an increase in recruitment of muscle fibres relative to increasing swimming speed up to 0.6-0.7 ms-¹ of the Ucrit, where the anaerobic (white muscle) activity started to exponentially augment with swimming speed, reaching up to ~7 times its initial value. Intensity of electromyogram signals were described by logarithmic (red muscle): y = 0.5922Ln(x) + 1.2251 (R ² = 0.9906) and exponential (white muscle): y = 0.0977e².⁴⁷²³x (R ² = 0.9845) relationships. Fine-tuning indicated that the two muscle types in the sea bass are involved in fuelling swimming activity below the Ucrit. Thus, scope for activity is not supported solely using aerobic metabolism, though the red muscle powers the majority of the swimming ability. Measurement of Ucrit displayed an average value of 3.43 BLsec-¹ (SE = 0.12). Associated EMG values measured during the forced swim trials using an implanted bio-sensitive radio transmitter showed that EMG's intensity increased, on average, 3.2 times between 0.2 msec-¹ and the Ucrit velocity (~1 msec-¹). Above EMG values were fine-tuned using estimates obtained from direct monitoring of the red and white musculature. Overall, the results demonstrated that the scope for activity, previously thought to represent only aerobic metabolism, is composed of both aerobic and anaerobic pathways. Fine-tuning of physiological transmitters to measure activity of free ranging fish can therefore be utilised to monitor the proportion of the scope of activity utilised in response to external stressors. This proportion and the level of compensatory ability remaining could represent a measure of well-being in cultured fish.
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