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1.
The probability of being employed varies depending on several factors. Many of these are related to personal characteristics such as educational level, age, gender, or number and age of children. Nevertheless, other factors may be relevant, in particular the geographical environment. The purpose of this paper is to analyse the relevance of urban size and the position of each territory (in terms of its distance from large metropolises) for the probability of being employed in the Spanish economy. Following the set of economic regions suggested by Polése, Shearmur and Rubiera (2007 ), we try to explain the spatial patterns of employment distribution. Our results show some relevant differences between these alternative economic areas. We find that municipalities with similar sizes and located at a similar distance from a metropolis but belonging to different Autonomous Communities or provinces share similar employability patterns.  相似文献   
2.
Eight synthetic casting materials were evaluated with respect to tensile and fatigue strengths, exothermicity (evolution of heat during polymerization), permeability (porosity), radiolucency, and cost. Strength determination for a five-layer sample included measurement of the ultimate load at which a material failed, the ability to absorb energy, and the stiffness a material possessed after application of a cyclic stress. Results indicated that Vet Cast was superior with respect to tensile and fatigue strengths. The exothermic reaction associated with the "curing" or polymerization process was evaluated and not considered excessive although Ultra Cast attained a temperature of 48.0°C and was uncomfortable to handle during application. Permeability was determined. Delta Lite and Hexcelite NS were the most permeable materials and dried more rapidly and thoroughly after immersion than the other casting materials. Hexcelite NS was considered the least radiolucent material and was the most expensive material studied. Each of the synthetic casting materials demonstrated superiority in one or more of the categories tested. No one product demonstrated consistent superiority in criteria appropriate for clinical application.  相似文献   
3.
Peripheral vasoconstriction and plasma catecholamine concentrations were studied in 37 dogs after cervical disc fenestration and salivary gland excision, laparotomy for intestinal anastomoses and cystotomy, or laparotomy for repair of diaphragmatic rupture, gastrotomy, and pyloromyotomy. Meperidine (4.4 mg/kg) was administered before extubation of 12 dogs undergoing laparotomy. Heart rate, respiratory frequency, indirect blood pressure, rectal temperature, toe web temperature, and plasma concentrations of epinephrine and norepinephrine were determined before induction of anesthesia, after intubation, after extubation, at sternal recumbency, and at standing. All dogs were hypothermic during surgery. After surgery, peripheral hypothermia (large rectal-toe web temperature gradients) increased from a mean of 4.6 degrees C after intubation to a mean of 10.4 degrees C when the dogs initially stood. Heart and respiratory rates and blood pressures during recovery were similar to those before anesthesia. Mean plasma catecholamine concentrations were neither significantly higher during recovery than before surgery nor were they increased in any surgical group, including the dogs not treated with meperidine. After anesthesia, 15% of the epinephrine and 12% of the norepinephrine samples were more than two standard deviations above the mean of the preanesthetic concentrations of all dogs. The ratio of all dogs with an epinephrine concentration more than two standard deviations above the mean of baseline epinephrine concentrations was greater at sternal recumbency than before anesthesia and the ratio of dogs with an increased epinephrine concentration at sternal recumbency was greater in the laparotomy dogs (9 of 24) than in the cervical surgery dogs (0 of 12).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
4.
The aim of the project reported here was to study the behaviour of a beagle bitch and her puppies using a video camera. This allowed continuous discreet observations of the animals throughout the twenty-four hours of each day. Changes in maternal behaviour from whelping to the start of weaning, and the way in which feeding and cleaning activity varied between daytime and night-time were easily assessed by the system. It was also possible to assess the effect of the presence of people during the day on the bitch's behaviour.  相似文献   
5.
We assessed by numerical modeling the coastal fish larval dispersion along the southern coast of Mallorca (Balearic Islands, NW Mediterranean) with the objective of determining the factors that contribute to successful recruitment. We assumed that fish larvae dispersal is mainly regulated by physical transport. Currents are mainly wind driven in this area; therefore, changes in wind forcing have a first‐order impact on larval transport. The synoptic wind patterns were systematically analyzed based on self‐organizing map analysis. The wind fields were clustered using a neural network pattern recognition approach into two modes, producing opposite along‐shelf flow. The seasonal changes between spring and summer in the dominance of either mode modulate the along‐shelf circulation, producing flow shifts under some circumstances. This variability in the wind regime was consistent throughout the 10 years analyzed (2000–2009). Using the Princeton Ocean Model (POM) and a particle‐tracking algorithm, we analyzed the effect of wind‐forced currents in the connectivity among near‐shore habitats. We show that, at the spatial scale considered, the coastal morphology and stochastic wind forcing favor local recruitment (mean of 30% self‐recruitment). Maximum transport distances of 20–30 km were typically associated with particles left to drift for 21 days. The implications for the performance of the four marine protected areas near SW Mallorca Island are discussed. Our results suggest that, although wind episodes determine the fate of short‐time spawning events, on a seasonal basis, regular larval supply to coastal zones is ensured by wind stochasticity.  相似文献   
6.
Flavonoids in Food and Their Health Benefits   总被引:17,自引:6,他引:17  
There has been increasing interest in the research of flavonoids from dietary sources, due to growing evidence of the versatile health benefits of flavonoids through epidemiological studies. As occurrence of flavonoids is directly associated with human daily dietary intake of antioxidants, it is important to evaluate flavonoid sources in food. Fruits and vegetables are the main dietary sources of flavonoids for humans, along with tea and wine. However, there is still difficulty in accurately measuring the daily intake of flavonoids because of the complexity of existence of flavonoids from various food sources, the diversity of dietary culture, and the occurrence of a large amount of flavonoids itself in nature. Nevertheless, research on the health aspects of flavonoids for humans is expanding rapidly. Many flavonoids are shown to have antioxidative activity, free-radical scavenging capacity, coronary heart disease prevention, and anticancer activity, while some flavonoids exhibit potential for anti–human immunodeficiency virus functions. As such research progresses, further achievements will undoubtedly lead to a new era of flavonoids in either foods or pharmaceutical supplements. Accordingly, an appropriate model for a precise assessment of intake of flavonoids needs to be developed.Most recent research has focused on the health aspects of flavonoids from food sources for humans. This paper reviews the current advances in flavonoids in food, with emphasis on health aspects on the basis of the published literature, which may provide some guidance for researchers in further investigations and for industries in developing practical health agents.  相似文献   
7.
Although many aspects of grass silage have received intensive study, the changes that take place within the grass blades during ensilage have received little attention.
In two factorial experiments Italian ryegrass (cv. Lemtal) and cocksfoot (indigenous) were ensiled in laboratory silos (capacity 0·2 kg) with the grass under pressure (700 Pa) and subjected to two treatments (with or without 3·31 t-1 85% formic acid) and two silos from each treatment opened on eight sampling dates(1,2,3,4,7,10,14 and 21 d).
For each sampling date transverse sections of grass laminae were examined and changes in the cross sections of the protoplasts and of cells, as defined by the cell walls, were recorded. These data were used to calculate the ratios of protoplast to cell volumes at each sampling date.
Each silage was analysed for dry matter, pH, lactic acid, VFA, ammonia and glucose. The distance settled by the silage (a measure of decrease in silage volume) and the silage conductivity were also recorded.
Both of the untreated grasses yielded silages with typical lactic acid levels and pH values. In all of the silages there was a marked shrinkage of the plast within the space defined by the cell wall. The ratio of protoplast to cell volume eventually stabilized at 0·4. The formic acid-treated grasses reached this level by day 1 but a longer period was required by untreated grasses.
It is suggested that the decrease in silage volume is related to the lactic acid content of the liquid phase due to their close relationship in silages produced from untreated grasses ( r = 0·97***).  相似文献   
8.
Growth chamber experiments were conducted in order to study the absorption, translocation and activity of glyphosate when applied to roots with aqueous solution avoiding any glyphosate–substrate interaction. Corn seedlings at the first leaf stage were set up in individual graduated cylinders containing different solutions of 14C-glyphosate (0–30 mg ae kg−1). After 26 h of root exposure, plants were transferred to fresh nutrient solution and grown for the next 5 days. After harvest, plants were separated into seed, root, mesocotyle, coleoptile, cotyledon, first leaf and all new leaves (apex), and quantified 14C radioactivity contained in each part. Glyphosate uptake was only 11% of the theoretical mass flow into the plant. The amount of glyphosate translocated from roots was positively correlated with plant uptake ( P  < 0.01). Total plant fresh weight presented a logistic response to glyphosate amounts, including a growth stimulant effect (hormesis), when plants absorbed less than 0.6 µg. The treated plants presented a normal pattern of glyphosate allocation, with the apex the principal sink, accumulating more than 38% of mobilized glyphosate. When corn plants absorbed more than 0.6 µg they showed a decrease in growth. The relatively high glyphosate quantities allocated in the new leaves showed the relevance of the symplastic pathway in the translocation process for root absorbed glyphosate.  相似文献   
9.
Two species of codlet (Bregmacerotidae) larvae were collected during nine survey cruises conducted in the south-eastern Brazilian Bight between 23oS and 30oS in 1985-91. Of 4846 codlet larvae collected during nine cruises, 99.2% were identified as Bregmaceros canton and only 0.8% were B. athanticus. The two species were more abundant during winter in the neritic region (60–135 m depth). Vertical distribution of codlet larvae was studied using the BIOMOC net, and vertical profiles of temperature/salinity and chlorophyll a concentration were recorded by CTD and fluorescent sonde. Only 9.0% of larvae were collected in the upper 30 m and 91.0% were found deeper (> 40 m). The depths of highest density of larvae bore a close relationship to the subsurface chlorophyll maximum layer. Some B. canton larvae were found in the upper 30 m layer at night, but no larva was found during the day. Water temperatures where B. canton larvae occurred ranged from 16 to 23oC, but most larvae were found at 18–20oC and in salinities of 35.5–36.5 psu.  相似文献   
10.
Objective — This article reports an alternative to septal resection in nasal septal deviations involving the rostral 7 to 10 cm of the nasal septum.
Study Design — Case report.
Sample Population — One client-owned foal.
Methods — A nasal approach with mucosal elevation was used to gain access to the cartilaginous portion of the nasal septum. Once exposed, a series of parasagittal incisions in the cartilage allowed the septum to be repositioned while providing some intrinsic stabilization.
Results — The nasal approach provided good access to the rostral 7 cm of the nasal septum. The technique resulted in minimal hemorrhage from the site. Bleeding was reduced with the use of ephedrine to vasoconstrict the mucosal vessels, and primary closure of the mucosa.
Conclusions — Use of an intrinsically stabilized septoplasty should be considered as a means of decreasing the airway obstruction caused by nasal septal deviation in foals while allowing for normal development of facial contour.  相似文献   
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