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Additional file 1: Table S1. Sequencing and mapping results. The table reports the RNA-Seq libraries sequenced including for each of them i) the number of raw reads obtained, ii) the number of reads after trimming and rRNAs removal iii) the number of mapped reads (and the percentage of mapped reads). Table S2. GSEA results. Enriched BIOCARTA Gene Sets (GS) at both the highest (up-regulation in “diet Y” condition) and lowest (up-regulation in “diet C” condition) part of the genes ranking are reported. ES: enrichment score; NES: normalized enrichment score; NOM p-val: nominal P-value.

A 7-year-old neutered female Doberman pinscher was presented with a palpebral nodule on the haired eyelid of the left eye. The nodule was removed surgically. Microscopically, the nodule was consistent with eyelid melanocytoma. The tumour was characterized by the presence of numerous lacunar and slit-like spaces filled by erythrocytes and interspersed throughout the neoplastic melanocytes. Immunohistochemically, these spaces were lined by cells expressing PNL2, but the cells were negative for factor VIII and CD31. [corrected] These findings were consistent with neoplastic melanocytes without endothelial cell participation. This feature was interpreted as 'vasculogenic mimicry', a mechanism of tumour angiogenesis that is well-recognized in human melanomas, but has not yet been reported in melanomas in animals.

The non-catalytic reforming of natural gas to syngas was studied numerically. The numerical simulations focused on the Virtuhcon Benchmark, which is a set of experimental data based on the semi-industrial scale test plant HP POX (high-pressure partial oxidation). The experimental data comprises reactor characteristics such as product gas composition and wall temperatures across the reactor for temperatures between 1473 and 1673 K and pressures between 50 and 70 bar(g), and optically estimated flame characteristics such as flame length and width. For turbulence-chemistry interactions, the widely used Eddy Dissipation Concept model and an advanced Flamelet/Progress-variable-based approach developed for POX processes were applied. Contrary to standard Flamelet approaches, the advanced model can describe correctly both the reaction zone and the comparatively slow chemical processes in the almost homogeneous post-flame zone. Based on the experimental data, the applicability of the different numerical models will be discussed carefully. In contrast to several literature work, the model evaluation is based not only on global reactor characteristics, but also on optical flame analyses from inside of the semi-industrial test plant, which allows to evaluate the capability of the numerical model to predict local reactive flow effects inside industrial HP/HT processes. The results reveal that both approaches allow a reliable prediction of the syngas composition, flame length, and flame width. With respect to the outlet temperature, the Eddy Dissipation Concept tends to overpredict the resulting temperature, or, from a different point of view, to underpredict the progress of the endothermic reforming conversion processes.

Strained two-phase pulverised coal flames in a counterflow configuration are investigated numerically. Three operating conditions with different coal-to-primary-air ratios and inlet velocities were evaluated in order to establish different flame regimes. At first, the two-phase flow of the fully resolved reference cases is calculated solving the transport equation for the species and directly evaluating the reaction rates. Different flame structures are identified using the heat release rate and the chemical explosive mode as markers, showing that complex structures with a combination of lean premixed and non-premixed flames can be observed in strained counterflow coal flames. In addition to the fully resolved simulation, the suitability of the Flamelet-Progress Variable (FPV) model is investigated. Both premixed and non-premixed tables are employed. At first, the suitability of the look-up tables is evaluated by means of an a priori analysis, using the fully resolved simulations as reference solutions, s...

A resolved laminar flow simulation approach is used to investigate the effect of enhanced oxygen levels on single coal particle ignition, comparing the numerical results against experimental data for well-defined conditions (Molina and Shaddix, 2007). Devolatilization is described by a generic boundary condition at the particle surface that accounts for both convective and diffusive phenomena during pyrolysis. The heating rate history of the particle is obtained by solving for intra-particle heat transfer and heat exchange between the particle and its surroundings. The time evolution of volatile release is captured by using the particle mean temperature to calculate the devolatilization rate from a single kinetic rate law with CPD-fitted parameters. The assumed volatile composition includes both light gases and larger hydrocarbons to represent tars. A skeletal kinetic mechanism for pyrolysis and oxidation of hydrocarbon and oxygenated fuels containing 52 species and 452 reactions is used to accurately describe homogeneous chemistry. Particle heat-up, pyrolysis, ignition and envelope flame stabilization are characterized in four gas atmospheres differing in oxygen content and the use of either N2 or CO2 as balance gas. In agreement with the experimental evidence, enhanced oxygen levels shorten ignition delay time τ ign and result in a higher intensity of the combustion process according to temperature and radical production peaks for all studied mixtures. For the studied oxy-mixtures the presence of CO2 in substitution of N2 delays ignition. The observed behavior is coherent with the different thermo-physical properties of the gas mixtures. The sensitivity of predicted ignition delay to a set of uncertainties is also discussed. It is found that while the absolute values of predicted ignition delay time are functions of potential particle preheating, particle Reynolds number and the chosen criterion to extract ignition delay, the relative trends among the gas mixtures remain in line with the experimental evidence.

The final carbon conversion rate is of critical importance in the efficiency of gasifiers. Therefore, comprehensive modeling of char particle conversion is of primary interest for designing new gasifiers. This work presents a novel intrinsic-based submodel for the gasification of a char particle moving in a hot flue gas environment considering CO2 and H2O as inlet species. The first part of the manuscript describes the model and its derivation. Validations against experiments carried out in this work for German lignite char are reported in the second part. The comparison between submodel predictions and experimental data shows good agreement. The importance of char porosity change during gasification is demonstrated. The third part presents the results of CFD simulations using the new submodel and a surface-based submodel for a generic endothermic gasifier. The focus of CFD simulations is to demonstrate the crucial role of intrinsic based heterogeneous reactions in the adequate prediction of carbon conversion rates.

CFD-Simulationen von kohlebeschickten Vergasern erfordern mehrere fortschrittliche mathematische Modelle, um die komplexen, mehrphasigen, reaktiven Stromungssysteme zu beschreiben. Insbesondere die Pyrolyse und die heterogenen Verbrennungs- und Vergasungsreaktionen des Kokses sind entscheidend fur die akkurate Beschreibung des Vergasungsverhaltens. Dieser Abschnitt zeigt, wie fortschrittliche Kohlekonversionsmodelle fur die Pyrolyse und die Kokskonversion mit der CFD gekoppelt werden konnen, mit dem Ziel korrekte Simulationen durchzufuhren und die benotigten Rechenressourcen zu limitieren. Die Ergebnisse werden abschliesend durch den Vergleich mit zwei Vergasungstests, die mit Kohlen unterschiedlichen Inkohlungsgrads (high-rank semi-anthracite bis low-rank lignite) durchgefuhrt wurden, validiert.

During oestrus, fattening female pigs are more prone to lameness, fractures and wounds due to mounting and agonistic behaviours of penmates. This study assessed the effect of sexual maturity on the behaviour and welfare of heavy female pigs slaughtered at 36 weeks of age (180±10 kg) for dry-cured ham production. An immunocastrated control group was used for comparison. In all, 56 15-week-old female pigs, individually identifiable by back tattoos were equally distributed among four pens. All animals from two pens were subject to a three-dose immunocastration schedule at 16, 20 and 32 weeks of age. Skin lesions and behaviours were assessed at 18, 23, 28, 33 and 36 weeks of age. A blood sample was collected at 20, 24, 28 and 32 weeks of age for assessing health/stress parameters and GnRH antibodies. At slaughter, ovaries were weighed, measured and histologically examined; stomachs, carcasses and lungs were scored for lesions and a further blood sample was taken. Immunocastrated pigs did not significantly differ from controls in growth rate, feed efficiency and slaughter performances (lung score, gastric score, backfat thickness). However, they showed a lower frequency of aggressive interactions at 33 and 36 weeks, lower front lesions at 28 weeks, but higher at 30 weeks; a lower haptoglobin level at 28 weeks, a lower level of cortisol and back lesions at slaughter (36 weeks). These findings suggest a low, yet not negligible, impact of sexual maturity on the welfare of heavy female pigs.

Partial oxidation (POX) reactors are characterized by different reaction regimes: the near burner zone is mainly governed by the mixing of the initially non-premixed reactants and by the fast oxidation zone, while the post-flame zone is mainly governed by the slow reforming reactions under almost fully premixed conditions. Advanced turbulence–chemistry interaction models are required to describe different regimes in POX reactors. This work investigates the use of the flamelet/progress variable (FPV) approach in laminar and turbulent POX reactors. The FPV approach allows different times and length scales to be captured, using a progress variable to describe the advancement of the reactions in reacting mixtures. The solution of the chemical reactions is generally separated from the solution of the flow and mixing by pre-calculating solutions of one-dimensional canonical flames. The solution of the chemistry is stored in look-up tables and linked to the solution of the flow using the mixture fraction and the progress variable scalars. In this work, different methods for generating the flamelet look-up tables are analyzed for a laboratory reference laminar POX flame. The results are compared to the direct numerical simulation with the goal of identifying the most suitable flame structure for tabulation in POX systems. These results are then used to build a FPV table. Finally, a pilot-scale high-pressure POX reactor was investigated and the numerical results are validated using the measured composition of the syngas at the exit of the reactor.

In this work advanced gasification models of four Australian coals were calibrated using laboratory-scale experiments with the aim of extrapolating these information for simulating large-scale gasification processes using CFD. In particular, the four studied coals, ranging from semi-anthracite to sub-bituminous, were extensively characterized using high-pressure bench and laboratory scale techniques. Coal devolatilization is modeled using the empirical competing two-step models, whose parameters are calibrated in a pre-processing step by means of the advanced CPD, FG-DVC and FLASHCHAIN® pyrolysis models. The results of the advanced pyrolysis models are at first validated against true volatile yield data obtained at high pressures and heating rates from wire-mesh reactor experiments. Char gasification is modeled using a n th-order intrinsic kinetics model. At first, intrinsic char kinetics was measured in kinetic regime from experiments in pressurized thermogravimetric analysis. Then, gasification experiments in a laboratory-scale pressurized entrained flow reactor have been used for estimating the reactivity in pore-diffusion regime, defining the diffusivity inside the particle pores. Finally, the calibration of the same coals have also been tested in a 5 MW pilot-scale gasifier, offering a unique opportunity to apply our model over the continuum of laboratory and pilot scales. The model results again show good agreement with the experimental data of syngas composition and carbon conversion evaluated at the exit of the gasifier. The simulations of the pilot-scale gasifier demonstrates that industrial-scale gasification processes can be accurately predicted using advanced coal conversion models, adequately calibrated through laboratory-scale experiments.

The present report describes two outbreaks of serious enteritis in commercial laying hens where Clostridium perfringens and Clostridium colinum were simultaneously detected. At the age of 44 and 31 weeks, two laying hen flocks showed an increase of the mortality rate and a worsening of productive performance. Post-mortem examination revealed intestinal necrotic-haemorrhagic ulcerations and hepatic focal necrosis. The bacteriological examination yielded the isolation of C. colinum and C. perfringens toxin type A, NetB positive. In one outbreak, C. colinum was detected also by polymerase chain reaction in all the intestines of affected birds. In laying hens, C. colinum has never been isolated but only suspected as the causative agent of a slight enteric disease called duodenal focal necrosis. The present case report was characterized by severe enteritis presumably due to the synergistic effect of C. colinum and C. perfringens.

The present study is a CFD investigation of the gasification behaviour of different of difficult coals at high pressure in the siemens 5-MW piolot-scale entrained-flow reactor. The detailed models for char conversion kinetics are adjusted based on laboratory investigations of the same coals and then coupled to the CFD framework for the full-scale simulations. The gasifiction reactions in entrained-flow reacteors predominantly take place in the so-called pore-diffusion regime. In order to correctly predict the carbon conversion, suitable models for intrinsic and pore evolution are required for each feedstock under the operating conditions considerded. In this work, the char gasification kinetics of the investigated coals are first characterized in separate laboratory-scale experiments for the kinetic and pore diffusion regimes. This data is used to calibrate the char conversion models, which are then coupled to the CFD code. This comprehensive modelling framework is finally used to simulate the conversion behaviour of the coals in the measured carbon conversions under different operating conditions (equivalence rations) and the syngas composition after quench. The analysis carried out in this work demonstrates that accurate that accurate predictions of carbon conversion in industrial-scale gasifiers can be obtained using advanced intrinsic char gasification models when calibrated with laboratory-scale experiments.

CFD modeling results for entrained flow coal gasification using advanced submodels for coal conversion are presented and compared to detailed experimental data. The focus of this investigation is on the accurate modeling of the char conversion process. The CBK/E and CBK/G models are used for calibrating a simplified Single Nth-Order Reaction (SNOR) kinetic model, which is suitable for CFD calculations. The kinetics of the CBK/G model are fitted using char gasification data obtained from drop tube furnace experiments. CFD simulations are performed for the BYU entrained flow gasifier fired with four different coals varying significantly in rank ranging from bituminous coal to lignite. The comparison with the experiments generally gives good agreement in terms of flame stand-off, gas composition and carbon conversion when the kinetics of the CBK/G model calibrated with drop tube experiments is used. On the other hand, lower carbon conversion is obtained using the default correlation of the CBK/G model, which only allows to depict the overall tendency of the gasification reactivity with coal rank.

In the present work, the combustion of a single char particle in quiescent and convective environments is investigated numerically. Fully resolved CFD calculations are carried out considering heterogeneous reactions at the particle surface and detailed homogeneous reactions in the gas phase. Unity and non-unity Lewis number diffusion modeling approaches are employed and compared to each other. The flame shape of the particle in a quiescent atmosphere shows full symmetry whereas the particle in the convective environment exhibits a stagnation region upstream of the particle and a wake region downstream of the particle. The detailed CFD results are used to analyze the flame structure around the char particle and corresponding flamelet simulations are carried out. For the presently investigated case, curvature effects of mixture fraction, species and temperature are found to be significant in almost all the cases. These curvature effects correspond to diffusion tangential to iso-surfaces of mixture fraction. To describe these processes, new extended flamelet equations are derived. The individual terms in the flamelet equations are analyzed for both the quiescent and the convective environment based on the CFD data and the results confirm the importance of tangential diffusion. Except for the quiescent environment and unity Lewis numbers, curvature cannot be neglected for the investigated char combustion case. For all other cases, significant differences between the standard flamelet model and the detailed CFD results are found. On the other hand, applying the extended flamelet equations yields very good agreement with the CFD results.

The scope of this investigation is the application and analysis of a recently developed submodel (Schulze et al., Oil Gas Science Technol, 2013, doi: 10.2516/ogst/2012069 ) for char particle combustion and gasification. The distinguishing feature of this model is a detailed representation of the diffusion and convection processes as well as the homogeneous reactions in the boundary layer around the char particle. These processes are fully coupled to the heterogeneous particle kinetics. The model was implemented into the CFD code ANSYS-Fluent. The coupled solver is used for simulating the IFRF full scale pulverized coal combustion MILD furnace, for which detailed experimental data are available for model evaluation (Orsino et al., IFRF Doc. No F46/y/3, 2000) The new model yields improved agreement with measured data as compared to the standard modeling approach. This can be directly related to the prediction of the char burnout rate. For further analysis, the mixing field in the IFRF furnace is investigated in detail by introducing four mixture fractions for pyrolysis products, char burn-off gases, primary and secondary air, respectively. The solutions of the respective transport equations are used to define the local stoichiometry both in the gas phase and on the particle surface in such a multi-stream system. The conditions in the particle surrounding gas phase as well as on the particle surface are used to define the regime of particle-gas interaction based on the simulations with the new submodel. It can be shown that for certain conditions the homogeneous reactions in the particle boundary must be accounted for.

In humans, the aryl hydrocarbon receptor (AHR) gene battery constitutes a set of contaminant-responsive genes, which have been recently shown to be involved in the regulation of several patho-physiological conditions, including tumorigenesis. As the domestic dog represents a valuable animal model in comparative oncology, mRNA levels of cytochromes P450 1A1, 1A2 and 1B1 (CYP1A1, 1A2 and 1B1), AHR, AHR nuclear translocator (ARNT), AHR repressor (AHRR, whose partial sequence was here obtained) and cyclooxygenase-2 (COX2) were measured in dog control tissues (liver, skin, mammary gland and bone), in 47 mast cell tumors (MCTs), 32 mammary tumors (MTs), 5 osteosarcoma (OSA) and related surgical margins. Target genes were constitutively expressed in the dog, confirming the available human data. Furthermore, their pattern of expression in tumor biopsies was comparable to that already described in a variety of human cancers; in particular, both AHR and COX2 genes were up-regulated and positively correlated, while CYP1A1 and CYP1A2 mRNAs were generally poorly expressed. This work demonstrated for the first time that target mRNAs are expressed in neoplastic tissues of dogs, thereby increasing the knowledge about dog cancer biology and confirming this species as an useful animal model for comparative studies on human oncology.

The objective of this work was to investigate the expression of heat shock protein 70 (HSP70) by Western blot (WB) in swine liver. Subsequently, the study aimed to apply this method to two experimental groups of heavy pigs raised in different confinement systems: intensive/indoor (Group A) and extensive/outdoor (Group B). Thirty-six crossbred commercial heavy pigs were divided as follows: Group A (eight castrated males and eight females) was equally distributed into two single-sex indoor pens (1.02 m2/pig); Group B (11 castrated males and nine females) was kept in one single (partially grassy and partially wooded) open area of about 6000 m2. Group A was slaughtered at 41 weeks of age (170 ± 9 kg) and Group B at 48 weeks of age (172 ± 13 kg). At the abattoir the livers of all the animals were collected and analyzed by WB assay in order to quantify the levels of HSP70. Moreover, a further liver sample was taken from the same animals in order to investigate the cellular localization of HSP70 by immunohistochemistry (IHC). The interaction between sex and group resulted statistically significant (P = 0.001). When stratified by sex, Group A showed significantly higher HSP70 values compared with Group B for both male and female subjects (P < 0.001). Stratifying by group, males showed significantly higher HSP70 values than females in Group A (P < 0.001), whereas no statistical differences were observed between sexes for Group B (P = 0.653). The IHC results evidenced cytoplasmic immunoreactivity in a granular pattern in both groups. The different expression pattern observed by WB could prove to be a useful tool in the assessment of pig health and welfare.

MILD (Moderate and Intensive Low oxygen Dilution) combustion is a novel approach to reducing NOx emissions and improving combustion efficiency in fossil fuels power plants. It is characterized by elevated temperature and high dilution of reactants and strong recirculation inside the combustion chamber which produce a low temperature increase, thus reducing NOx formation. The main differences with conventional combustion concern the chemical reactions that take place in almost the entire volume of the combustion chamber and the uniformity of both temperature and the chemical species concentration. For this reason advanced turbulence-chemistry interaction models with detailed kinetic mechanisms are required to accurately simulate MILD by means of CFD calculations. The main aim of this work is to deepen the influence of turbulence-chemistry interaction on pulverized coal MILD combustion and to understand which models are more accurate and suitable to reproduce the process. In particular, two turbulence-chemistry interaction models are analyzed. On one hand, a conventional model based on infinitely fast chemistry Eddy Dissipation Model with a two-step global kinetic mechanism is considered. On the other hand, an advanced model based on finite rate chemistry Eddy Dissipation Concept is considered and used with both a global and detailed kinetic mechanisms. The results are finally compared with an experimental test-case. From the comparison, advanced turbulence-chemistry models used with complex kinetic mechanisms give, as expected, the best agreement with numerical results, despite the higher computational resources required.

A comprehensive CFD model has been developed to simulate the gasification process within an air-blown updraft coal gasifier. Updraft fixed bed gasification processes are characterized by complex behavior, since they involve different space- and time-dependent sub-processes where coal preheating, drying, de-volatilization and char reactions take place. Simplified models, such as non-dimensional ones, useful for preliminary gross mass and energy balance, are unable to correctly simulate the overall gasification phenomena and more sophisticated approaches are required. In particular, CFD models could be used to describe in a detailed way the complex time- and space-dependent phenomena involved in the gasification process. Considering the high volume fraction of the solid phase, close to the packing condition, the Euler–Euler approach is required to model this multiphase flow. The solid phase is considered as a continua according to the kinetic and plastic theory of granular flows. The operation of a Wellman–Galusha gasifier is investigated, considering a non-continuous loading of coal and extraction of the ash, with the aim of characterizing the space- and time-dependent behavior of the process.

To evaluate muscle fiber degeneration (MFD) associated with white striping and wooden breast, pectoralis major of 192 broilers differing for genotype (standard vs. high breast yield), gender, and feeding regime (ad libitum vs. restricted rate 80% from 13 to 21 d of age) were sampled at 14, 21, 28, 35, and 46 d of age for histological analyses by hematoxylin and eosin (HE) staining to evaluate tissue morphology, Masson's trichrome to identify collagen presence, and Oil red and Nile blue for lipid presence. Microvessels (diameter ≤15 μm), nuclei positive to anti-cleaved lamin A and monoclonal proliferating cell nuclear antigen (PCNA) antisera were counted to assess apoptotic and regenerative processes, respectively. Significant differences were found according to feeding system, age, and their interactions. The frequency of chickens with MFD was higher with ad libitum than restricted feeding (75.0% vs. 62.5%; P = 0.01) and increased with age (18.8%, 28.1%, 75.1%, 96.9%, and 96.9% at 14, 21, 28, 35, and 46 d). However, at 14 d a similar frequency (18.8%) was found in all broilers; at 21 d, MFD occurred more in broilers fed ad libitum than in those under restriction (50.0% vs. 6.3%; P 0.01); at 28 d differences were reduced (87.5% vs. 62.5%; P = 0.10) to disappear by 35 (100% and 93.8%) and 46 d (96.9% and 96.9%). The number of microvessels decreased with age (20.7 to 9.46; P 0.001) and the number of nuclei positive to the anti-cleaved lamin A antibody increased. At histology, MFD at 46 d corresponded to loss of typical cross striations, massive necrotic process, degenerating fibers surrounded by inflammatory cells, scattered fibers in an abundant collagen-rich connective tissue, numerous adipose cells; necrotic fibers showed a high percentage of apoptotic nuclei, and regenerating fibers appeared positive to anti-PCNA antibody. In conclusion, MFD soon occurred after 2 wk of growth and increased dramatically within 28 d. Early feed restriction reduced MFD as long as animals were restricted, but no residual effect was recorded after re-alimentation.

Avian astroviruses, of the genus Avastrovirus, are recognized as being the cause of enteritis in different bird species worldwide. In particular, turkeys are very susceptible and can be severely affected by this viral agent. More recently, astroviruses were detected in diseased guinea fowl in Italy but whether or not they were the causative agents of the clinical disease was not established. Despite the distribution and relevance of Avastrovirus infection, very little information on pathogenesis or factors influencing the pathogenicity of astroviruses is available. To increase available data on the pathogenesis of these viruses and to test the hypothesis of possible interspecies transmission, experimental infections were carried out in turkeys and guinea fowl with two genetically distinct avian astroviruses, namely TK-6363 and GF-5497, originating respectively from diseased turkey poults and guinea fowl. Data obtained in our study show that both of the viruses selected were able to infect young birds of the species in which they were originally detected. Additionally, these viruses were able to infect young birds of different species causing clinical signs, thus providing experimental evidence for the infection of distinct avian astroviruses in different avian species.

NOx are one of the most important pollutants produced during combustion of fossil fuels. Emissions of NOx from combustion systems are primarily in the form of nitric oxides (NO). They are generally produced from the oxidation of the nitrogen contained in the atmospheric air or by the oxidation of the nitrogen-bounded compounds in the fuel. NO is the main compound produced from the combustion; however, once it has been released in the atmosphere, it rapidly reacts producing NO2, which is more stable than NO. For this reason, NO2 are generally regulated as representative NOx compound. In general, NOx are toxic, they also react to form smog and acid rain, and they play a central role in the formation of ozone in the troposphere. In addition, NOx, is a major greenhouse gas. This article reviews the mechanisms that govern the formation of NOx emissions from fossil fuels combustion and the main transformations in the atmosphere. Thermal, prompt, and fuel NOx mechanisms are presented. Finally, the modern technologies for mitigating the NOx emissions from power systems are presented, divided as precombustion, combustion modifications, and postcombustion techniques. Keywords: NOx emission; NOx sources; environmental impact; combustion processes; mitigation techniques

The aim of this study was to evaluate the histomorphology and the stress response in the bivalve Venerupis philippinarum sampled in four differently polluted sites of the Venice Lagoon (Palude del Monte, Marghera, Ca' Roman and Val di Brenta). This species is often used as bioindicator of environmental pollution since it can bioaccumulate a large variety of pollutants because of its filter feeding. Chemical analyses for heavy metals (Cd, Cu, Hg and Pb) and polycyclic aromatic hydrocarbons (PAHs) were performed on whole soft tissues of V. philippinarum. The histological evaluation of clams revealed the presence of Perkinsus sp. infection in animals from all sites, although a very high prevalence of parasites was evidenced in clams from Ca' Roman. Perkinsus sp. were systemically distributed in the mantle, in the intestine and digestive gland, in gonads and gills. The trophozoites of Perkinsus sp. were found isolated or in cluster surrounded by a heavy hemocitical response. Haemocytes always exhibited an immunopositivity to cytochrome P4501A (CYP1A), heat shock protein 70 (HSP70), 4-hydroxy-2-nonenal (HNE) and nitrotyrosine (NT) antibodies. The digestive gland of animals from Palude del Monte showed the highest malondialdehyde (MDA) concentration, whereas clams from Ca' Roman exhibited the highest quantity of metallothioneins.

The histological status of the thymus, blood cortisol concentration and circulating neutrophil:lymphocyte ratio were evaluated in 349 slaughtered beef cattle, to assess the potential of these parameters as indirect biomarkers of the illegal use of corticosteroids in meat production. The livers of 20 of the animals were analysed chemically for residues of corticosteroids. The morphology of the thymus was examined for adipose tissue infiltration, cortical atrophy and ‘starry sky’ appearance, and on the basis of these characteristics, the animals were considered to be negative, suspected or positive for illegal corticosteroid treatment. The animals considered to be negative had a mean cortisol concentration that was significantly higher (29 ng/ml) than that of the animals suspected for corticosteroid treatment (22 ng/ml). Using the chemical analysis as the gold standard for identifying illegally treated animals, the histological examination of the thymus had a sensitivity of 100 per cent and a specificity of 85 per cent. The samples that were positive by chemical analysis had cortisol concentrations of less than 2·0 ng/ml, whereas the mean cortisol concentration of the negative samples was 10·3 ng/ml.

The ongoing H5N1 Asian epidemic is currently affecting a number of avian species including ducks. These birds are an important part of the poultry industry in the affected countries, and it is likely that they are acting as a reservoir of infection. Ten Pekin ducks were challenged with 100 μl containing 107 50% egg infective dose of the highly pathogenic avian influenza virus (HPAIV) A/Duck/Vietnam/12/05 (H5N1), administered by an intra-nasal and oral route. Clinical symptoms were recorded twice a day up to 14 days postinfection (dpi). Clinical signs were first noted at 2 dpi, with conjunctivitis and slight depression, and progressed over a period of 1–3 days to severe neurologic signs consisting of torticollis, incoordination, tremors, and seizures. Survival times varied from 3 to 7 dpi. On postmortem examination, hemorrhages were observed in the duodenum, ceca, proventriculus, ventriculus, trachea, pancreas, and brain. Histologic lesions, as well as immunohistochemistry positivity, were recorded in the pancreas and brain. In situ hybridization revealed viral antigen associated with acinar pancreatic cells, bronchial epithelial cells, and with cells of the central nervous system as well as neurons of the submucosal plexus of the duodenum. Our experimental findings agree with those previously observed in ducks naturally infected with HPAIV H5N1 viruses, confirming the acquired viral neurotropism and pancreatotropism, as previously noted in other avian species, as well as in humans.

SQUAMOUS cell carcinoma of the sinuses has been described in many animal species, particularly in horses (Junge and others 1984, Dixon and Head 1999, Head and Dixon 1999), dogs (Rogers and others 1996) and cats (Murphy and others 1989, Mukaratirwa and others 2001). However, none has been reported in captive, wild bovids kept in zoos. Among the order Artiodactyla, one cutaneous squamous cell carcinoma has been described in a Wyoming pronghorn (Antilocapra americana americana) (Effron and others 1977). The addax (Addax nasomaculatus), of the order Artiodactyla, class Bovidae, family Antilopinae, is the most desertadapted of the antelopes, living in sandy and stony regions of the Sahara desert (Kingdon 1997). This short communication describes the gross and microscopic examination of a captive addax living in a zoo, which had squamous cell carcinoma of the frontal sinus and nasal conchae, with pulmonary and lymph node metastases. A 10-year-old, 90 kg, male addax kept in the municipal zoo of Lignano, northern Italy, showed respiratory distress, a mucous bloody nasal discharge, anorexia and cachexia. Antibiotic therapy with intramuscular enrofloxacin failed to reduce the respiratory signs, and the addax was euthanased. A few months previously, a small cutaneous nodule in the frontal region of the animal’s head had been surgically excised. At postmortem examination, the nodule had regrown; an ovoid, 5 x 4 cm area of erosion on the right side of the frontal bone surface was evident. The bone was friable; its consistency was reduced and easy to cut. The frontal sinus contained a yellowish, spongy mass in its ventral portion, which also invaded the caudal nasal conchae through the ethmoidal bone. The same type of proliferative mass was found in the orbital cavity at the emergence of the optic nerve, and appeared to be connected to the frontal sinus. Haemorrhage was detected in the brain cortex and in the maxillary sinus. The retropharyngeal lymph nodes were hyperplastic, and some whitish nodules of approximately 0·5 cm in diameter were recognised in the lung. No other organs were involved. Samples of the neoplastic mass, retropharyngeal lymph nodes, the cutaneous nodule, lung, liver and kidney were fixed for routine histopathology. Histologically, the mass showed a diffuse proliferation of neoplastic cells of epithelial origin, with a high degree of pleomorphism and squamous differentiation (Fig 1). The tumour cells had large, ovoid and hyperchromatic nuclei, with prominent multiple nucleoli, and abundant eosinophilic cytoplasm. They showed variable degrees of squamous metaplasia and keratinisation, with an appearance of ‘horn pearl’ formation. The neoplastic growth was infiltrative, with large areas of necrosis and haemorrhage. The mitotic activity was high, at three to four mitotic figures per high-power field. The retropharyngeal lymph nodes, the nodule excised from the skin and the lung (Fig 2) were affected by neoplastic proliferation characterised by the same histological features as the mass found in the sinuses. In contrast, the liver and the kidney were not involved. Immunohistochemistry was performed on selected sections of neoplastic tissue using monoclonal mouse antihuman cytokeratin antibodies (M821, 1:100; Dako). Antigen retrieval was obtained by digestion with trypsin for 30 minutes at 37°C. The EnVision Peroxidase (K4000; Dako) detection system, using 3,3′-diaminobenzidine tetrahydrochloride (D-5905; Sigma) as the chromogen, was applied. The neoplastic tissue showed strong cytoplasmic positivity to cytokeratin, thus confirming the epithelial origin of the neoplasia. On the basis of the gross, microscopic and immunohistochemical characteristics, a diagnosis of squamous cell carcinoma of the frontal sinus and nasal conchae with retropharyngeal lymph node and pulmonary metastases was made. The many types of tissue in the nasal cavity give rise to a variety of types of neoplasm. Almost all of the malignant neoplasms reported are of epithelial origin, but some neoplasms of mesenchymal origin are also reported (Madewell and others 1976). Considering the influence of the gross anatomy of the nasal and paranasal sinus cavities on the growth pattern and spread of sinonasal tumours, neoplasias in this region can grow by expansion alone or by expansion and infiltration. Tumours of the frontoconchal sinus can readily extend via the large frontomaxillary ostium into the caudal maxillary sinus, and vice versa (Head and Dixon 1999). In the present case, the tumour invasion within the sinus cavities did not allow identification of the primary site of the tumour. However, the neoplastic growth pattern indicated that the tumour had expanded both cranially and caudally, following the anatomical communications between the sinuses. Furthermore, metastases in the retropharyngeal lymph nodes, lung and skin were detected. Distant metastases have seldom been recorded with sinonasal tumours, lymph node metastases being more commonly recorded (Head and Dixon 1999). The present case contributes to the limited information available on tumour pathology in captive wild Bovidae, highFIG 2: Multiple metastatic foci of neoplastic involvement are seen in the lung. Haematoxylin and eosin. Bar=25 μm FIG 1: Histological appearance of the neoplastic mass. There is a diffuse proliferation of neoplastic cells of epithelial origin, with high grade pleomorphism, mitotic activity and squamous differentiation. Large areas of necrosis are also present. Haematoxylin and eosin. Bar=100 μm

In transonic turbine stages, the exit static pressure field of the vane is highly non-uniform in the pitchwise direction. The rotor traverses periodically this non-uniform field and large static pressure fluctuations are observed around the rotor section. As a consequence the rotor blade is submitted to significant variations of its aerodynamic force. This contributes to the high cycle fatigue and may result in unexpected blade failure. In this paper an existing transonic turbine stage section is redesigned in the view of reducing the rotor stator interaction, and in particular the unsteady rotor blade forcing. The first step is the redesign of the stator blade profile to reduce the stator exit pitchwise static pressure gradient. For this purpose, a procedure using a genetic algorithm and an artificial neural network is used. Next, two new rotor profiles are designed and analysed with a quasi 3D Euler unsteady solver in order to investigate their receptivity to the shock interaction. One of the new profiles allows reducing the blade force variation by 50%.Copyright © 2004 by ASME

At the end of 2008, two young dogs, a threeyear- old male Maltese and a one-year-old male Lhasa apso, belonging to the same dog breeder (Veneto region, north-eastern Italy), died with clinical signs of renal failure. At postmortem examination, bilateral nephritis with green-yellowish uroliths was

TUMOURS are not uncommon in domestic and pet birds ([Petrak and Gilmore 1982][1], [Reece 2003][2]), but are an unusual finding in free-living and captive birds ([Effron and others 1977][3], [Siegfried 1983][4], [Dillberger and others 1987][5], [Renner and others 2001][6]). Most reports of neoplasia