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1.
This investigation was carried out to compare the postoperative analgesia and plasma morphine concentrations in dogs given epidural morphine or epidural morphine combined with medetomidine prior to surgery. Twelve dogs (seven males and five females) with ruptured cranial cruciate ligaments presented to the Washington State University Veterinary Teaching Hospital. Six dogs received an epidural injection of morphine (0.1 mg/kg) and six dogs received epidural morphine (0.1 mg/kg) combined with medetomidine (0.005 mg/kg). Numeric rating scale (NRS) pain scores and cumulative pain scores (CPS) were assigned to 10-min segments of video. Video segments, heart rates and respiratory rates were recorded prior to premedication and at 4, 8, 12, 18 and 24 h after epidural injection. Blood was sampled from the cephalic vein at each of these times and during anesthesia at 0.5, 1, 2 and 3 h after epidural injection. Data were analyzed using either Friedman's test or one-way anova for repeated measures. In the morphine group, significant increases compared with premedication values were detected at 4, 8 and 12 h after epidural injection for NRS and at 4 and 12 h after epidural injection for CPS. In the morphine plus medetomidine group, NRS was significantly higher at 4 and 8 h whereas there were no differences from baseline values for CPS. Plasma morphine concentrations were not significantly different between treatment groups, but were significantly increased compared with preinjection values at 0.5, 1, 12, 18, and 24 h in the morphine plus medetomidine group. Epidurally administered morphine combined with medetomidine was associated with only minor benefits based on subjective pain scoring when compared with morphine alone in these dogs undergoing repair of a ruptured cranial cruciate ligament.  相似文献   
2.
Fe-rich concretions commonly occur in Greek soils with alternating drying and waterlogging periods. This study was conducted to characterize the iron oxides in Fe-rich concretions from the upper solum of an Alfisol with seasonal perched water table by the combination of selective dissolution and X-ray diffraction (XRD) techniques. The results showed that more than 75% of the total iron (Fet) was associated with the crystalline and the amorphous Fe oxides, indicating a strong accumulation of free iron oxides (Fed) in concretions. Amorphous iron compounds (Feo) was present at high concentrations and fluctuated with profile depth. The active Fe ratio (Feo/Fed) values that ranged from 0.35 to 0.41 reflected an association of poorly crystalline goethite with some ferrihydrite. The XRD data showed that the Fe-rich concretions consisted of quartz, feldspars, illite and gypsum. The mineralogy of iron oxides in concretions was determined by comparison of XRD patterns for dithionite-citrate-bicarbonate (DCB) treated (deferrated) and untreated (non-deferrated) samples. Poorly crystalline goethite as demonstrated by broad lines in the diffraction patterns and ferrihydrite were the iron oxides detected in the concretions. This mineral assemblage appears to be related to the pedoenvironmental conditions in which the concretions were formed and indicates that the mechanisms governing the formation of crystalline Fe oxides from ferrihydrite are retarded by the presence of crystallization inhibitors.  相似文献   
3.

Context

This study investigates post-fire natural regeneration of Aleppo pine (Pinus halepensis) forests at Ilia region (Peloponnesus, Greece) following the catastrophic fire of 2007.

Aims

The objective of this study is the prediction of P. halepensis post-fire regeneration at a regional scale through an integrated geographic information systems (GIS) model as a basis for post-fire management plans.

Methods

The model was developed in three interconnected stages: (1) field data collection, (2) development of two prediction models (based on interpolation of field data and multi-criteria evaluation (MCE) that combined factors known to affect regeneration), and (3) combination of applied models using Bayesian statistics.

Results

Post-fire pine regeneration presented high variation among the studied plots. Redundancy analysis revealed the positive effect of fallen branches and a negative correlation with altitude. Both modeling approaches (geostatistical and MCE) predicted the post-fire pine regeneration with high accuracy. A very significant correlation (r?=?0.834, p?<?0.01) was found between the combined final model and the actual number of counted seedlings, illustrating that less than 10?% of the studied area corresponds to sites of very low post-fire pine regeneration.

Conclusions

The combination of GIS models increased the prediction success of different levels of pine regeneration. Low-altitude areas with low grass cover overlying tertiary deposits were proved the most suitable for pine regeneration, while stands developing on limestone proved least suitable. The proposed methodology provides management authorities with a sound tool to quickly assess Aleppo pine post-fire regeneration potential.  相似文献   
4.
This study reports on the concentrations, distribution, and availability of heavy metals in the children’s playground soils of Athens. Playgrounds were chosen because they are open city areas; they show relatively even spatial distribution within the district of Athens and are used by a great number of young children and their escorts on a regular basis. Samples were collected from 70 playground surface soils, representing more than 70% of the city’s playgrounds. Cu, Zn, Pb, Cr, Ni, Co, Mn, and Fe were extracted by aqua regia and by diethylene triamine pentaacetic acid (DTPA) to estimate total and available metal forms, respectively. Their mean total concentrations were 43, 174, 110, 80, 82, 22, 312, and 17?×?103?mg kg?1, respectively. The DTPA-extracted fraction showed much lower values, with means of 2.5, 7.8, 5.8, 1.5, 1.3, 0.4, 8.4, and 2.0 mg kg?1 respectively, which, however, should be carefully monitored since they relate directly to the bioavailable fraction of heavy metals. Though mean values of metal concentrations are not particularly high, the calculated enrichment factors indicate site-specific cases of high enrichment with heavy metals. Considering that the bioavailable fraction of a metal is possibly a more appropriate indicator for the recent soil pollution history, availability ratios were calculated and their distribution was visualized over the entire city profile using the appropriate GIS software. It was shown that recent metal pollution events appear to have affected mostly playground sites in the southern and eastern part of the municipality.  相似文献   
5.
The various iron fractions were quantified by selective dissolution (Fed, Feo, Fet) in four Red Mediterranean soils, developed on metarhyolite and metadolerite. They were similar in all profiles. A strong trend of iron removal from the surface horizon and of its subsequent illuvial translocation to the argillic horizons was observed. In all profiles, Feo was not related to the organic matter content indicating the Mediterranean xeric soil environment. The Feo/Fed ratio and the percentage of crystalline iron oxides (Fed-Feo) suggested that the pedoenvironment in which the profiles P1, P2 were formed, allowed the high crystallization of iron oxides. As indicated by the Fed/Fet values, the weathering process was more intense in the metarhyolite-developed soils. In contrast, the metadolerite-developed soils present conditions of poorly crystallized iron oxides and a lower degree of development.  相似文献   
6.
The main objective of this study was to investigate the performance of faba bean landraces originating from different regions of Greece under both organic and conventional farming systems focusing mainly on yield, biological nitrogen fixation (BNF), and competitiveness to weeds. Faba bean exhibited a high ability to fix nitrogen from the atmosphere, as indicated by the percentage of N2 derived from the atmosphere which exceeded 75% in all evaluated varieties, and the total amount of biologically fixed N up to full anthesis, which fluctuated from 118.5 to 193.9?kg?ha?1 in the various cropping systems and cultivars. The weed density was appreciably higher in the organic plots, without significant differences among the faba bean cultivars, while wild mustard and corn poppy were the most competitive weeds. The application of inorganic starter fertiliser in the conventionally-treated plots had no negative effect on biologically-fixed nitrogen by faba bean plants, while the herbicide pendimethalin had no negative impact on the nodulation process. Protein concentrations in faba bean cultivars fluctuated from 27.3% to 31.4%. The evaluated landraces could be utilised in breeding programmes due to their earliness, and their high performance in terms of protein content, BNF ability, and productivity.  相似文献   
7.
Cotton is still one of the most important crops in Greece despite the changes in the country’s socioeconomic status which have reduced the total cultivated area. In order to minimize yield losses, weed control is essential during the cultivation period. The aim of this study was to determine the distribution of the prevalent weeds that escape the usual herbicide application in the main cotton zone, located in the Karditsa prefecture. The weed densities and the irrigation methods used were recorded in 101 sampling sites of 25 m2; the cotton crop had been grown for the last 5 years using similar weed control techniques. Existing soil maps of the area were also used, through which soil data (texture and carbonates content) were accessed. Among the 14 weed species that have been recorded, four were perennial (Cyperus rotundus, Convolvulus arvensis, Cynodon dactylon, Sorhum halepense) and were ranked as first, second, fourth and fifth, respectively, according to the mean density, indicating the inefficient herbicidal control. In the fields irrigated by sprinklers, the weeds occurred in greater populations than those that occurred in fields irrigated by drippers, at values of 4.64 and 3 weeds m-2, respectively. In terms of the studied soil properties, the distribution of C. arvensis was significantly correlated with carbonate content and soil texture in the surface soil layer. The autocorrelation analysis showed that only perennial weeds are spatially correlated whereas the interpolated maps showed this spatial trend of weed appearance.  相似文献   
8.
Farmer field schools (FFS) represent an alternative lifelong learning approach aimed at enhancing farmers' competences and skills through nonformal education. In this study we examined if farmers' participation in FFS is motivated by their social-psychological needs and whether these needs can be fulfilled through participation in FFS. Findings revealed that the possibility to participate in FFS is higher for farmers who experience lower levels of closeness and connectedness with their community peers and for those who score low on belongingness satisfaction. Furthermore, our analysis confirmed that FFS attendance increases felt community acceptance and facilitates the satisfaction of the belongingness need.  相似文献   
9.
The Dadia forest complex, in the Evros prefecture, in north eastern Greece was designated as a nature reserve in 1980 in order to protect the black vulture (Aegypius monachus) and other raptors. In this paper, the impacts of the protection on the forest growth were assessed using geographic information system (GIS) technologies. The major requirement for almost all research needed for sustainable forest management is extensive and intensive monitoring. GIS is a convenient tool for integrating remotely sensed data and various other kinds geo-referenced data. Detailed spatial and temporal change patterns of the land uses in the area were quantified by interpreting aerial photographs of the years 1945 and 1973 and a satellite image of 2001. The results showed that the rate of forest growth is significantly larger during the second period (1973–2001) than during the earlier one (1945–1973). This is mostly due to the introduction, in 1980, of a protection regime, including two high-protection core areas, and a buffer zone. From 1945 to 2001 the openings which are important as hunting biotopes for raptors were significantly decreased. Apart from the protection of the area that was played an important role in the forest changes the effects of various landscape parameters (elevation, slope, distance from the roads and urban areas, aspect, soil depth, geology, erosion and forest density) on these changes were examined.  相似文献   
10.
Jojoba (Simmondsia chinensis (Link) Schneider) explants were cultured in vitro on a basal medium supplemented with sodium chloride up to 169 mM during the proliferation stage. At the second and third month of salinity stress, the mineral nutrition (macro- and micro-elements) of the explants was assessed. Explants accumulated significant amounts of sodium and chloride (jojoba is an ‘includer’) while potassium, manganese, phosphorus and nitrate concentration was reduced. The concentration of the other elements did not exhibit significant changes. Each level of salinity stress affected the nutrient status of the explants distinctively. Jojoba explants tolerate salinity up to a level of sodium chloride concentration (113 mM), without showing any stress symptoms. Above this level, the salinity stress impact was observed as succulence and chlorosis of leaves and shoots.  相似文献   
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