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T. McGilvray D. Berner E. Beltran C. Attipa B. Dunkel 《Equine Veterinary Education》2021,33(2):e57-e60
A 22-year-old Irish Sport Horse presented following a period of bilateral blindness with subsequent spontaneous resolution. Brain magnetic resonance imaging (MRI) demonstrated features consistent with pachymeningitis. Cerebrospinal fluid (CSF) analysis revealed increased numbers of basophils, suggestive of an immunologic or neoplastic aetiology. It was suspected that the enlarged meninges led to compression of the optic nerves in the optic canals, causing bilateral blindness. Initial spontaneous remission, as seen in this case, has been reported in human patients with this condition. Pachymeningitis should be considered as a possible cause of cranial nerve deficits, including bilateral and unilateral blindness, in horses. 相似文献
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George I. Mantanis Jozef Martinka Charalampos Lykidis Libor Ševčík 《Wood material science & engineering》2020,15(5):303-311
ABSTRACT The objective of the work was to evaluate the efficacy of two new polyphosphate-based fire retardants (FRs) and one commercial product named Siriono® on the fire performance and physical–mechanical properties of medium density fibreboard (MDF) fabricated in the laboratory from Scots pine (Pinus sylvestris L.) wood. The fibres were treated with aqueous solutions of fire retardants, at 12% loading (dry salt on dry wood), and bonded with a melamine urea formaldehyde (MUF) adhesive. The physical and mechanical properties of panels were assessed using the European standards, whereas their fire performance was evaluated using an in-house method and the Cone calorimeter. In overall, the chemicals added enhanced the fire and smoke properties of the panels to varying degrees. Critical FR parameters such as peak heat release rate (peak HRR), total heat release (THR) and total smoke production (TSP) were significantly improved in the FR-treated panels, as exhibited in cone calorimeter tests. However, the internal bond strength of treated panels largely decreased by the addition of fire retardants, while thickness swell and water absorption negatively affected to a significant extent. In contrast, the formaldehyde release of the panels was considerably decreased at the E1 class level, with the incorporation of the polyphosphate-based additives. 相似文献
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Simple prediction of the survival of follicles in cryopreserved human ovarian tissue 总被引:2,自引:0,他引:2
Maltaris T Dragonas C Hoffmann I Mueller A Beckmann MW Dittrich R 《The Journal of reproduction and development》2006,52(4):577-582
This study examines the possible predictive value of the LIVE/DEAD fluorescence viability assay for evaluation of survival of cryopreserved human ovarian tissue. Ovarian tissue from ten patients was examined by LIVE/DEAD viability staining before and after cryopreservation and after freezing in a -20 C freezer (negative control). After cryopreservation with a slow freezing protocol and cryoprotectant the LIVE/DEAD assay showed 86% viable follicles (an intact oocyte and at least more than 50% of the granulosa cells alive), whereas after freezing at -20 C the survival rate was 67%. The healthy follicular loss after cryopreservation was 4%, whereas with freezing at -20 C, it was 25%. Although this assay overestimates the survival rate of cryopreserved primordial follicles, if the LIVE/DEAD assay yields greater than approximately 85% viable follicles, it can be assumed that the follicles in the cryopreserved tissue have maintained their developmental potential and that the tissue is suitable for retransplantation. 相似文献
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Concentrated Animal Feeding Operation activities lead to soil degradation in vicinity with the livestock breeding facilities, mainly due to ammonia emissions from the various stages of the process. In this research, the soil degradation effects of an intensive hog farming operation (IHFO) located at a Mediterranean limestone soil coastal area, have been investigated. Soil samples of the upper mineral soil were taken in various distances (10?C1,500?m) and directions from the IHFO boundaries. Thirteen experimental cycles were carried out in the duration of 1.5?years starting in March 2009 until October 2010. The soil samples were analysed on total, exchangeable and water-soluble Al, Fe and Mn. Significantly higher concentrations of the exchangeable and water-soluble Al, Fe and Mn were observed on soil samples at increasing proximity downwind from the farm (south). Southern soil average concentrations of exchangeable Al3+, Fe3+ and Mn2+ ranged between 3.56 and 7.45?mmol Al3+ kg?1 soil, 5.85 and 7.11?mmol Fe3+ kg?1 soil and 2.36 and 5.03?mmol Mn2+ kg?1 soil, respectively. Southern soil average concentrations of water-soluble Al, Fe and Mn forms ranged between 1.1 and 4.6?ppm Al, 0.5 and 0.8?ppm Fe and 0.4 and 1?ppm Mn, respectively. 相似文献
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Jarvis P Rey A Petsikos C Wingate L Rayment M Pereira J Banza J David J Miglietta F Borghetti M Manca G Valentini R 《Tree physiology》2007,27(7):929-940
Observations on the net carbon exchange of forests in the European Mediterranean region, measured recently by the eddy covariance method, have revived interest in a phenomenon first characterized on agricultural and forest soils in East Africa in the 1950s and 1960s by H. F. Birch and now often referred to as the "Birch effect." When soils become dry during summer because of lack of rain, as is common in regions with Mediterranean climate, or are dried in the laboratory in controlled conditions, and are then rewetted by precipitation or irrigation, there is a burst of decomposition, mineralization and release of inorganic nitrogen and CO(2). In forests in Mediterranean climates in southern Europe, this effect has been observed with eddy covariance techniques and soil respiration chambers at the stand and small plot scales, respectively. Following the early work of Birch, laboratory incubations of soils at controlled temperatures and water contents have been used to characterize CO(2) release following the rewetting of dry soils. A simple empirical model based on laboratory incubations demonstrates that the amount of carbon mineralized over one year can be predicted from soil temperature and precipitation regime, provided that carbon lost as CO(2) is taken into account. We show that the amount of carbon returned to the atmosphere following soil rewetting can reduce significantly the annual net carbon gain by Mediterranean forests. 相似文献
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Charalampos Lykidis Athanasios Grigoriou Ioannis Barboutis 《Wood material science & engineering》2014,9(4):202-208
This paper investigates the potential of utilising wood biomass from fruit tree branches and evergreen hardwood shrubs as raw materials in the production of particleboards when mixed with Greek fir wood particles. The main mechanical properties of the boards made therefrom were determined and compared with those made of typical industrial wood (IW) particles. The highest modulus of rupture and elasticity (30.0 N/mm2 and 4330 N/mm2, respectively) in bending and screw withdrawal (SW) resistance (127.8 N/mm) were reported for boards made of Greek fir and were downgraded when the fruit tree branches or evergreen hardwood shrub particles also participated. The participation of fruit tree branch particles in proportions higher than 50% improved the internal bond (IB) of fir produced boards, while the highest IB strength (0.95 N/mm2) was reported for boards made of fruit tree branches. Particleboards made of evergreen hardwood shrubs showed inferior mechanical properties compared with those made of IW particles. The latter also showed superior bending strength but inferior SW resistance compared with boards made of fruit tree branches. Hygroscopic and other properties are under determination and will be presented and discussed in the second part of the work. 相似文献
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Stylianos Liodakis Charalampos Michalopoulos Elpida Efthymiou Georgios Katsigiannis 《Water, air, and soil pollution》2012,223(1):169-179
One of the main environmental impacts of concentrated animal feeding operations is the soil degradation in vicinity with the
livestock breeding facilities due to substances such as ammonia emitted from the various stages of the process. Owing to the
high temperatures of the Mediterranean ecosystems, the evolution of gasses is more extensive and the soil degradation is consequently
more severe than those obtained in northern Europe. In this research, the soil degradation effects of a large meat-producing,
processing, and packaging unit have been investigated. The investigated intensive hog farming operation (IHFO) is located
at a limestone soil coastal area with sea to the north and hills to the south. Soil samples of the upper mineral soil were
taken in various distances and directions from the IHFO boundaries. Thirteen experimental cycles were carried out in the duration
of 1.5 years starting in March 2009 until October 2010. The soil samples were analyzed on pH and electrical conductivity (EC)
values as well as NH4
+ and NO3
− concentrations. Significantly higher concentrations of the two nitrogen forms were observed on samples at increasing proximity
downwind from the farm (south). Southern soil average NH4
+ and NO3
− concentrations ranged between 0.4–118 μg NH4
+-N g−1 soil and 6.1–88.4 μg NO3
−-N g−1 soil, respectively. The variation of emitted gasses depositions was clearly reflected in the average pH and EC values. Average
pH and EC values downwind from IHFO boundaries varied between 7.1–8.2 and 140–268 μS/cm, respectively. 相似文献