23 research outputs found
Evaluation of maternal antibody levels for establishing the vaccination program against Newcastle disease in ostrich chicks
ABSTRACT Newcastle disease virus (NDV) is known as one of the most important endemic viral pathogen for various avian species such as ostrich, in Iran. Therefore, establishing a routine vaccination program against ND in ostrich flocks would be useful in order to reduce the danger of this infection. Newcastle disease occurs among the ostriches and leads to high rate of mortality while most of the losses are among the youngest ones. This experiment was designed to follow up the changes of maternal antibody in ostrich chicks during the first weeks of their life. At this point of view, 700 one day old ostrich chicks were monitored and every seven days interval 10 blood samples were taken regularly and the titers of maternal antibody in their sera were studied. The haemagglutination inhibition (HI) test was used to evaluate the amount of anti-ND antibody. After hatching this study followed up to 49 th day. Due to our findings, the day 30 is recommended as a proper time to start the vaccination program against ND in flocks of ostrich chicks with maternal antibody
Indirect estimation of electrical resistivity by abrasion and physico-mechanical properties of rocks
This paper attempts to estimate electrical resistivity from physico-mechanical and abrasion properties of rocks. For this purpose, the electrical properties of rock samples collected from igneous and metamorphic formations were initially measured in a laboratory by employing the two-electrode method. In addition, physical, mechanical, and abrasion properties of the rocks were determined. Then, an attempt was made to examine the possibility of estimation of electrical resistivity from other rock properties. In this sense, it was found that water content, porosity, and the ratio of Vp/Vs have significant effects on the electrical resistivity. Moreover, we report that indirect tensile strength and static elastic modulus indirectly control the electrical characteristics of rocks, since reasonable correlations exist between them. Nevertheless, the reliability of the effect of rock abrasion on the resistivity could not be confirmed with a high degree of certainty. More data are needed to check its validity. Thus, we conclude in light of statistical analyses that the results of the tests and the relationships are statistically significant. For this reason, the electrical resistivity of the intact rock can be indirectly estimated by accounting for the physico-mechanical properties for a given formation. However, rock abrasion cannot be considered for the same purpose. © 2017 Elsevier B.V.Council for Higher Education University of ArizonaThe Council of Higher Education in Turkey is acknowledged for financially supporting the laboratory tests performed at the University of Arizona
Development of turbulent wakes evolving from asymmetric shear layers
This paper reports an experimental investi-
gation on the response of a turbulent wake past
an elongated flat plate to various upstream flow
conditions. Different tripping wires were placed
on the upper side of the plate downstream the
leading edge resulting in asymmetric shear lay-
ers evolving from the trailing edges. Mean flow
and turbulent fields of the asymmetric wakes
were compared to their symmetrical counter-
part. The symmetrical wake was found to attain
a self-similar state whereas asymmetric wakes
continued to slowly evolve towards an expected
asymptotic behaviour at a rate that strongly de-
pends on the imposed initial conditions.Papers presented to the 12th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Costa de Sol, Spain on 11-13 July 2016
Green entrepreneurship orientation, green innovation and hotel performance: The moderating role of managerial environmental concern
This study investigates whether hotels’ environmental and organizational performance is improved through green entrepreneurship, innovation, and managerial environmental concern. Through an online survey questionnaire, 271 responses were collected from hotel employees. The collected data were analyzed using PLS-SEM. The results suggest that green entrepreneurship orientation (GEO) has a direct and significant impact on environmental performance (EP) and organizational performance (OP). In addition, green innovation (GI) mediated the relationship between GEO, EP, and OP. Furthermore, when green innovation is used, managerial environmental concern (MEC) leads to higher environmental performance. However, its impact on GI and OP relationship was not significant. The present study offers important implications for hotels and service industries as it demonstrates the significance and role of green entrepreneurship, green innovation, and managerial environmental concern in improving performance in the hotel industry
Isolation of Ornithobacterium rhinotracheale from the brains of commercial broiler breeder chickens with meningitis and encephalitis
Ornithobacterium rhinotracheale (ORT) has been identified as one of the respiratory bacterial pathogens in turkey and chicken flocks. Four live birds displaying severe torticollis were submitted from a 13-week-old commercial broiler breeder chicken flock located in Mazandaran province. These birds were suspected to
pasteurellosis by the farm veterinarian. No other marked gross lesion except emaciation was seen. Histopathologic examination of the brains showed mild to moderate meningeal vasculitis, perivascular cuffing with lymphocytes, degeneration and necrosis of purkinje cells in the cerebellum. Viral culture of the brains
especially for Newcastle disease and avian influenza viruses was negative. Bacterial culture of the brains onto the blood agar revealed pure growth of Ornithobacterium rhinotracheale. In this study molecular confirmation of ORT by using of a very specific polymerase chain reaction (PCR) was carried out. Amplification products of a 784 bp region of the 16S rRNA gene of ORT confirmed the bacterium identification. This is the first field case
of ORT isolation from the brain of commercial chickens in Iran. These data suggest that this bacterium should be considered in differential diagnosis in cases of avian nervous signs. Further studies are necessary to confirm if ORT is a primary pathogen in such cases
Remote sensing in management of mining land and proximate habitat
Although remote sensing technology has been available for many years, it has rarely been used for monitoring mining activity. Recent studies indicate that remote sensing is also a valuable tool for managing and planning certain aspects of the mining operation. In this paper, we examine areal expansion of marble quarries and the affected vegetation over a period of 10 years in the Mugla region in Turkey, using geographic information system (GIS) and remote sensing (RS) techniques. Images captured by ASTER Level 3A01 (3D Ortho Data Set), Landsat 5, and Landsat 7 satellites between 2001 and 2009 were used for the analysis. Changes in the natural vegetation as a function of the production level in the marble quarry were calculated using the normalized difference vegetation index. According to the study results, land cover and natural vegetation decreased by less than 3 per cent and 1 per cent respectively between 2001 and 2009, following an upsurge in mining activity in the region
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Vibro-Acoustic Platelet Activation: An Additive Mechanism of Prothrombosis with Applicability to Snoring and Obstructive Sleep Apnea
Introduction: Obstructive sleep apnea (OSA) and loud snoring are conditions with increased cardiovascular risk and notably an association with stroke. Central in stroke are thrombosis and thromboembolism, all related to and initiaing with platelet activation. Platelet activation in OSA has been felt to be driven by biochemical and inflammatory means, including intermittent catecholamine exposure and transient hypoxia. We hypothesized that snore-associated acoustic vibration (SAAV) is an activator of platelets that synergizes with catecholamines and hypoxia to further amplify platelet activation. Methods: Gel-filtered human platelets were exposed to snoring utilizing a designed vibro-acoustic exposure device, varying the time and intensity of exposure and frequency content. Platelet activation was assessed via thrombin generation using the Platelet Activity State assay and scanning electron microscopy. Comparative activation induced by epinephrine and hypoxia were assessed individually as well as additively with SAAV, as well as the inhibitory effect of aspirin. Results: We demonstrate that snore-associated acoustic vibration is an independent activator of platelets, which is dependent upon the dose of exposure, i.e., intensity x time. In snoring, acoustic vibrations associated with low-frequency sound content (200 Hz) are more activating than those associated with high frequencies (900 Hz) (53.05% vs. 22.08%, p = 0.001). Furthermore, SAAV is additive to both catecholamines and hypoxia-mediated activation, inducing synergistic activation. Finally, aspirin, a known inhibitor of platelet activation, has no significant effect in limiting SAAV platelet activation. Conclusion: Snore-associated acoustic vibration is a mechanical means of platelet activation, which may drive prothrombosis and thrombotic risk clinically observed in loud snoring and OSA. © 2023 by the authors.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]