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91.
A 3‐year‐old French bulldog was presented to the ophthalmology service of the Vetsuisse Faculty, University of Zurich with a 3‐day history of conjunctival swelling of the left eye (OS). Ophthalmologic examination revealed a moderate conjunctival hyperemia and chemosis. A migrating foreign body having entered the conjunctival fornix behind the nictitating membrane was suspected. Within the first 24 hours of medical management, OS developed a panuveitis and a scleral perforation was highly suspected. Ocular and orbital ultrasound as well as conventional magnetic resonance imaging (MRI) examinations failed to confirm the presence of a perforating foreign body. A High‐Resolution MRI (HR‐MRI) using a microscopy coil was then performed with findings consistent with a perforating and migrating foreign body. A grass awn of 12 mm length was surgically retrieved “ab externo” from its’ point of entry into the sclera. To the best of our knowledge, HR‐MRI has not yet been used to examine canine eyes. This case report supports the idea that orbital imaging can be greatly enhanced with the introduction of HR‐MRI using microscopy coils with clinically relevant implications.  相似文献   
92.
93.
This study describes a detailed and systematic investigation on the effect of thermal processing in terms of temperature and time (kinetic study) on β-carotene in vitro bioaccessibility in carrots. β-Carotene in vitro bioaccessibility increased with increasing processing temperature and time until steady-state conditions were reached after prolonged heating. The bioaccessibility values in steady-state conditions were temperature dependent. The experimental bioaccessibility data could adequately be modeled with a fractional conversion model. For the first time, modeling of processing-induced bioaccessibility changes is reported in literature. The results of the present kinetic study were used to estimate the impact of industrially relevant thermal processes on β-carotene bioaccessibility in carrots by simulation. It was shown that, to achieve a high β-carotene bioaccessibility, processing of carrots is essential (i.e., on the one hand, intense thermal processing or, on the other hand, mild thermal processing combined with intense mechanical processing).  相似文献   
94.
The quality of development in intensive or mesocosm hatchery‐reared Dicentrarchus labrax larvae was investigated using physiological indicators assessing ontogeny. Larvae were reared in intensive (120 L tanks) and in mesocosm systems (20 m3 enclosures) with the same feeding sequence, excluding the wild zooplankton naturally available in mesocosms. Faster growth was recorded since early development [16 day after hatching (DAH)] in the mesocosm. Maturation of the digestive system also occurred earlier as indicated by the higher amylase secretion ratios, the intestinal maturation index (alkaline phosphatase/leucine–alanine peptidase and aminopeptidase‐N/leucine–alanine peptidase ratios) and the more developed intestinal epithelium at 23 DAH. Nevertheless, the delay in digestive maturation in the intensive system seemed retrieved within few days. In both the groups, the number of vertebrae ranged between 24 and 26, with the dominant class being 25 vertebrae. However, the distributions differed between treatments for meristic characteristics, ossification stages and incidence of malformation types. Loss of a vertebra was more frequent in the intensive system, while the appearance of an additional vertebra was more frequent in the mesocosm. Ossification at 37 DAH was also more advanced in the mesocosm in addition to a lesser rate and severity of skeletal malformations. It is suggested that the early nutritional contribution of mesocosm wild zooplankton, yet at densities of 0.2–0.7 prey mL?1, had key effects on larvae development since the early stages.  相似文献   
95.
Soil hydraulic parameters are essential inputs to agricultural and hydrologic models for simulating soil moisture. These parameters however are difficult to obtain especially when the application is aimed at the regional scale. Laboratory and field methods have been used for quantifying soil hydraulic parameters but they are proved to be laborious and expensive. An emerging alternative of estimating soil hydraulic parameters is soil moisture model inversion using remote sensing (RS) data. Although soil hydraulic parameters could not be derived directly from remote sensing, they could be quantified by the inverse modeling of RS data. In this study, we conducted a multi-criteria inverse modeling approach to estimate the rootzone soil hydraulic parameters in a rainfed rice field at depths 3, 12, 28 and 60 cm, respectively. The conditioning data used in the inverse modeling are leaf area index (LAI) and actual evapotranspiration (ETa) from satellite imageries, and soil moisture (SM) data from in situ measurements. The performances of all the model inversion experiments were evaluated against observed soil moisture in the field, and measured LAI during the growing season. The results showed that using remotely sensed LAI and ETa in the inverse modeling provided a good matching between observed and simulated soil moisture down to 28 cm depth from the soil surface. With the addition of soil moisture information from the site, the model inversion significantly improved the soil moisture simulation up to a depth of 60 cm.  相似文献   
96.
This study was conducted on an irrigated area of southern Italy to analyze the current operation of a large-scale irrigation delivery system and the effects of the operation procedures on crop irrigation management and aquifer salinity increase. The area is characterized by relatively high levels of groundwater salinity in the summer that are probably due to intensive groundwater pumping by farmers during periods of peak irrigation demand, with the resulting seawater intrusion. Two alternative delivery schedules, namely the rotation delivery schedule and the flexible delivery schedule, referred to as RDS and FDS, respectively, were simulated using a soil-water balance model under different combinations of crop, soil and climatic conditions. The first set of simulations concerned the farm irrigation management constrained by the rotational delivery used by the local water management organization. The second scenario simulated the farm irrigation schedule most commonly used by growers in the area for maximizing crop yields. Based on crop irrigation management under RDS and FDS, two alternative operational scenarios were also developed at the scheme level and then compared for evaluation. Winter and summer salinity maps of the aquifer were developed by interpolating salinity measurements of the groundwater samples collected during the 2006 irrigation season. From these maps, a close relationship can be inferred among delivery schedule, aquifer exploitation and salinity increase, which justifies the need for implementing FDS that might reduce the groundwater demand for irrigation.  相似文献   
97.
Recent findings on the molecular damage occurring in the stallion spermatozoa are reviewed. Mechanisms leading to cell death or survival are briefly overviewed, and recent discoveries on molecular pathways leading to sperm death and sublethal damage are discussed. Increasing the understanding of this particular area may disclose clues to develop new strategies to improve current sperm conservation methods.  相似文献   
98.
Before natural plant allelochemicals can be exploited as biological pesticides against weeds and for disease control, more than the effect on target organisms needs to be known. This study presents results of aquatic biotests using four organisms, namely, a water flea, a freshwater alga, a soil alga, and a luminescent bacterium. The tested substances were 10 benzoxazinone derivatives, 3 of them known to be wheat allelochemicals, benzoxazolin-2(3H)-one (BOA), 6-methoxybenzoxazolin-2(3H)-one (MBOA), and 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3-one (DIMBOA), and 7 identified degradation intermediates and metabolites. For comparison, two commercial pesticide formulations (BAS, Betanal) were tested by applying the same set of biotests. The data set produced could be seen as an ecotoxicological evaluation for effects of allelochemicals against nontarget organisms and as a base for further risk assessment.  相似文献   
99.
Interactions between plants and microorganisms can significantly affect plant health and productivity as well as ecosystem functioning. Detailed knowledge of the tripartite relationships between plants, fungi, and bacteria, and their environment is still limited. In the present study, the soils adjacent to three plant species (Cruciata laevipes, Mentha piperita, Equisetum arvense) in the Ljubljana Marsh and the bulk, plant-free soil were analyzed for their bacterial community structure in June and October 2006. The terminal restriction fragment length polymorphism analysis indicated a different bacterial community structure in the rhizosphere and in bulk soil, however, with almost no seasonal changes between late spring and autumn samples and no apparent impact of the three plant species. In addition, root colonization of the three plant species by arbuscular mycorrhizal fungi (AMF) and dark septate endophytes (DSE) was microscopically assessed monthly from May until October 2006. A presumably accidental correlation between monthly precipitation and the degree of arbuscule formation, with the latter lagging 1 month, was noted for M. piperita, the most heavily colonized of the three plant species. With all three plants, the phosphorus content in roots correlated positively with most AMF structures. Microsclerotia of DSE were mainly abundant in autumn samples. Fungal diversity in roots was estimated using temporal temperature gradient gel electrophoresis separation of the fungal polymerase chain reaction products obtained for both 18S-rDNA and the 5.8S-ITS2-28S rDNA segments. No specific effects of either plant species or seasonal changes on mycorrhizal community structure were discernible.  相似文献   
100.
We investigated to develop effective procedures to recover the potentially high-added-value phenolic compounds contained in the discontinuous three-phase olive processing wastewaters (OMW). Particular emphasis was made to extract and purify hydroxytyrosol, one of the major compounds occurring in OMW. Batch optimization experiments showed that ethyl acetate is the most efficient solvent for the recovery of phenolic monomers from OMW. The latter was used with an optimal pH equal to 2. Furthermore, the percentage of each monomer, and particularly hydroxytyrosol, in the extract was maximum for a solvent ratio and a theoretical extraction stage number equal to 2 and 3, respectively. High yield (85.46%) recovery of hydroxytyrosol was achieved from OMW using a three-staged continuous counter-current liquid-liquid extraction unit. Hydroxytyrosol (1.225 g) were extracted per liter of OMW. One gram of hydroxytyrosol per liter of OMW was then purified by means of a chromatographic system which could be adapted to a large scale production process.  相似文献   
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