72 research outputs found

    Oocyst excretion pattern of three intestinal Eimeria species in female rabbits.

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    Abstract: The dynamic change in faecal Eimeria oocyst excretion was evaluated in 10 naturally infected female rabbits, starting from their weaning at 33 d of age until about 1 mo after their second parturition. Faecal samples collected from examined animals were quali-quantitatively analysed to evaluate presence and number of Eimeria oocysts. In addition, isolated Eimeria oocysts were identified at the species level following sporulation. Animals were found to be infected by Eimeria perforans, Eimeria exigua and Eimeria magna and shed Eimeria oocysts after weaning and after parturition. In particular, at 33 d of age all female rabbits examined were negative, while the discharge of Eimeria oocysts started at 39th day of age and peaked between 46th and 53rd day of age. From 81-109 d of age until the first parturition and from 25 d of age of the litters born at the first parturition to the second parturition, all animals resulted negative. After parturition, Eimeria oocyst output occurred from 6th to 12th day after the first parturition and from 7th to 13th day after the second parturition, while a second period of oocyst excretion was observed from 18th to 24th day after both parturitions. These findings may indicate the existence of a relationship between the periparturient phase and Eimeria oocyst output and suggest an important role of the mothers in transmission of the infection to their litter

    Fluid-Assisted Strain Localization in Quartz at the Brittle/Ductile Transition

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    A mylonitic quartzite with conjugate and synthetic shear bands was investigated by Electron Backscatter Diffraction and optical microscopy to obtain insights on recrystallization mechanisms and strain localization in quartz at plastic to semibrittle conditions close to the brittle-ductile transition. The mylonitic quartzite deformed during late Miocene thrusting coeval with contact metamorphism in the high-strain domains of the Calamita Schists (Elba Island, Italy). Mylonitic deformation occurred from amphibolite to lower greenschist facies conditions during cooling of the aureole. Dynamic recrystallization, dominated by the activity of dislocation creep by prism slip, produced recrystallized quartz layers mantling relic large quartz porphyroclasts. Under decreasing temperature and fluid-rich conditions, quartz porphyroclasts acted as relatively rigid bodies and fractured along synthetic and conjugate C′ shear bands. Shear bands developed along kinematically favored orientations, just locally assisted by weak crystallographic planes in quartz. Fracturing along shear bands was assisted by cataclasis and fluid infiltration enhancing fracture propagation and healing by recrystallization and authigenesis of new quartz and phyllosilicate grains. The process enhanced the propagation of and strain localization in shear bands, with the development of bands of weak phyllosilicates. Furthermore, we observed the development of a c axis preferred orientation (CPO) related to dissolution and precipitation of new grains with their c axis oriented parallel to shear bands. This study highlights the importance of the interplay between brittle and crystal-plastic processes and fluid ingress in the semibrittle regime to understand deformation partitioning and strain localization

    Fluid-rock interaction, skarn genesis, and hydrothermal alteration within an upper crustal fault zone (Island of Elba, Italy)

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    The Terranera magnetite-hematite-pyrite deposit of the Island of Elba (Italy) is an historical skarn deposit hosted by a fault zone of regional importance (Zuccale Fault) and by its hanging wall rocks. We combine field observations with petrographic data, electron probe microanalyses (EPMA), XRPD data, fluid inclusion microthermometry, and element imaging by Laser Ablation-Inductively Coupled Plasma-Time of Flight Mass Spectrometry (LA-ICP-TOFMS) to define the ore-forming process at Terranera. We show that in this location the fault is made of four levels of mineralized fault rocks having distinct mineral compositions. In these levels, a mineral association made of diopside, clinozoisite, and other Mg-rich minerals is replaced by magnetite, hematite, pyrite, Mg-hornblende, clinochlore, and other Mg-rich phyllosilicates. This paragenesis is overprinted by goethite and clay minerals. Chlorite-quartz geothermometry and fluid inclusion microthermometry show that ore precipitation occurred at 350–180 °C from fluids of distinct bulk salinities, but goethite and clay mineral overprinting progressed at lower T. We propose that Terranera is a magnesian Fe skarn formed due to the interaction between distinct hydrothermal fluids and a dolomitic protolith, which was preserved within the fault zone. These fluids mixed and cooled during protolith metasomatism, causing ore precipitation due to oxidation and desulfidation. A very similar process was described in a large deposit of Elba (Rio Marina). Argillic alteration was widespread within the fault but met permanently intermediate sulfidation conditions. Trace element composition of hematite shows that Terranera has features that overlap those of skarn and epithermal deposits. In particular, elements that are typical of epithermal deposits (Sb, Ga, Ge, As) occur at mass fractions (50–200 μg/g) that are either unreported or not typical of hematite from skarn deposits. These features identify Terranera as formed in an ore environment that was transitional between that of a skarn and of an epithermal deposit. These features are shared by other historical deposits located at Elba and in the massive pyritic ore district of south Tuscany (e.g., Gavorrano, Fenice Capanne). This indicates that a similar environment might have occurred during the Neogene beyond Elba, in a much larger ore district of south Tuscany

    Analysis of the antibiotic resistance profiles in methicillin-sensitive s. Aureus pathotypes isolated on a commercial rabbit farm in Italy

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    The breeding of meat rabbits is an important sector in the livestock industry in Italy. The focus of this study was to describe the antibiotic resistance profile distribution among the Methicillin-sensitive Staphylococcus aureus isolated in a rabbit farm. From 400 animals of different ages and three farm workers, 96 randomly selected strains isolated from various anatomical sites and lesions were analysed. According to spa typing and the resistance profiles towards veterinary and human antibiotics, 26 pathotypes were identified. The highest resistance was observed against Tetracyclines (92.3%) and Macrolides (80.8%), while almost all were susceptible to Penicillins, according to the limited use of β-lactams on the farm. In total, 92.3% of pathotypes were multidrug resistant (MDRs). Two MDR pathotypes belonging to the t2802 spa type were isolated from both farmers and rabbits. Age categories harboured significantly different pathotypes (p = 0.019), while no association was found between pathotypes and lesions (p = 0.128) or sampling sites (p = 0.491). The antibiotic resistance was observed to increase with the time spent in the farm environment (age category). The selective pressure exerted by antibiotic use acted by giving advantage to more resistant strains rather than by lowering susceptibility to various drug categories within strains

    CSF biochemical correlates of mixed affective states

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    To evaluate the question of whether “mixed” bipolar disorder is a distinct entity, we compared selected cerebrospinal fluid (CSF) biochemical parameters from patients with bipolar disorder, mixed, to those with mania and major depression. Fourteen patients in each category (DSM-III) were studied with regard to CSF HVA, 5HIAA, sodium, potassium, calcium, and magnesium levels under carefully controlled conditions. CSF HVA, 5HIAA, and sodium were found to be significantly higher in manics than in major depressives. Discriminant analysis of the biochemical variables of the mixed affective group identified two biochemically distinct and clinically different subgroups of seven patients each, one resembling the manic group and the other the major depressive group. These findings suggest that mixed affective states do not exist as a separate entity, but are compsed of two subgroups obtained from the manic and major depressive categories.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66203/1/j.1600-0447.1988.tb06339.x.pd

    Using exergy to analyze the sustainability of an urban area

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    The extended exergy analysis method, taking into account the mean life time cycle of building, has been applied to evaluate the sustainability of an urban area. The impact of the emissions due to the life cycle of the buildings has been evaluated. Two thermodynamic indexes, gI and gII showing, respectively, the first and second law efficiency of buildings, have been proposed as thermodynamic indexes. The applied methodology provides a single thermodynamics environmental criterion for the selection of technological alternatives, strategies and designs that produce lower environmental impacts connected to higher exergy indexes gII
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