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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
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1. We take issue with a proposal to irrigate cotton crops from Cooper Creek, as the development would be in sharp contrast to the ‘boom-and-bust’ character of the local environment. In dryland rivers the flow regime is influenced by aseasonal climatic phenomena like the Southern Oscillation, so that patterns are highly variable and averages are virtually meaningless. Some irrigation developments on dryland rivers have been planned during periods that were unusually wet and, as a result, present levels of water use are not sustainable. 2. Long, dry periods are the norm in dryland rivers. The biota tolerate drought and respond to occasional floods that may have long-enduring effects (riparian trees, for example, may live for centuries). All are sensitive to the rates of rise and fall and the amplitude, duration and frequency of floods. Where the flood pulse is erratic, as in Cooper Creek, species with opportunistic traits are likely to dominate. Base flows and seasonal variations imposed by irrigation use present a very different physical environment for these species. The plan to tap the Cooper headwaters would amplify the impacts because this region is a refuge for flora and fauna. 3. In general, we contend that the Cooper Creek ecosystem could not accommodate a competitor for water that is vital for its own maintenance, and that the irrigation proposal could be rationalized only in the sophistry of short-term economics. © 1997 John Wiley & Sons, Ltd. 相似文献
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OLIVER BERRY PHILLIP ENGLAND DAVID FAIRCLOUGH GARY JACKSON JIM GREENWOOD 《Fisheries Oceanography》2012,21(4):243-254
Determining the extent of dispersal in exploited marine fishes is essential for understanding their population dynamics and optimising management. The West Australian dhufish, Glaucosoma hebraicum, is a highly sought‐after, large and long‐lived reef‐dwelling species, endemic to south‐western Australia. Stock assessments indicate that this indicator species is overexploited. The fishery is managed using a zone‐based system, which implicitly assumes a high degree of demographic independence among zones. While tagging studies indicate limited movement of adult G. hebraicum, there is no understanding of the spatial scale of dispersal of its larvae and thus the true extent of interdependence of management zones. We analysed 13 microsatellite DNA loci to characterise the extent of gene flow, and conducted particle tracking simulations to model larval transport in this species. Genetic data demonstrated that some local recruitment was likely, but that on a broad scale gene flow between the management zones was extensive, and the entire fishery represents a single genetic stock. Hydrodynamic modelling predicted that the majority of dhufish larvae recruit from within the management zone where they are spawned, and that inter‐annual variation in current velocities has limited effect on the extent of larval transport. Because management zones are likely to be largely independent in terms of both larval and adult recruitment, heavy localised fishing pressure has the potential to reduce the abundance and reproductive capacity of this species in highly fished areas, but it should have limited impact on neutral genetic diversity. 相似文献
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F. TÓTH N. FRANK T. MARTIN‐JIMÉNEZ S. B. ELLIOTT R. J. GEOR R. C. BOSTON 《Equine veterinary journal》2010,42(2):149-155
Reasons for performing study: Hyperinsulinaemia is detected in horses with insulin resistance (IR) and has previously been attributed to increased pancreatic insulin secretion. Connecting peptide (C‐peptide) can be measured to assess pancreatic function because it is secreted in equimolar amounts with insulin and does not undergo hepatic clearance. Hypothesis: A human double antibody radioimmunoassay (RIA) detects C‐peptide in equine serum and concentrations would reflect responses to different stimuli and conditions. Methods: A validation procedure was performed to assess the RIA. Six mature mares were selected and somatostatin administered i.v. as a primed continuous rate infusion, followed by 50 nmol human C‐peptide i.v. Insulin and C‐peptide concentrations were measured in horses (n = 6) undergoing an insulin‐modified frequently sampled i.v. glucose tolerance test, and in horses with insulin resistance (n = 10) or normal insulin sensitivity (n = 20). Results: A human RIA was validated for use with equine sera. Endogenous C‐peptide secretion was suppressed by somatostatin and median (range) clearance rate was 0.83 (0.15–1.61) ml/min/kg bwt. Mean ± s.d. C‐peptide‐to‐insulin ratio significantly (P = 0.004) decreased during the glucose tolerance test from 3.60 ± 1.95 prior to infusion to 1.03 ± 0.18 during the first 20 min following dextrose administration. Median C‐peptide and insulin concentrations were 1.5‐ and 9.5‐fold higher, respectively in horses with IR, compared with healthy horses. Conclusions: Endogenous C‐peptide secretion decreases in response to somatostatin and increases after dextrose infusion. Results suggest that relative insulin clearance decreases as pancreatic secretion increases in response to dextrose infusion. Hyperinsulinaemia in insulin resistant horses may be associated with both increased insulin secretion and decreased insulin clearance. Potential relevance: Both C‐peptide and insulin concentrations should be measured to assess pancreatic secretion and insulin clearance in horses. 相似文献
5.
利用热脉冲技术对雷州半岛25年生加勒比松人工林旱季 (2000年10月至2001年2月)树干液流特征、耗水及环境因子的关系进行研究.结果表明:加勒比松边材不同位点的液流密度由外到内呈低-高-低的态势;观测期间林分日液流密度变幅为411～4 120 L·m-2·d-1,日平均液流密度为2 084 L·m-2·d-1;旱季无雨时,加勒比松日液流密度与太阳辐射、饱和蒸汽压差、气温及湿度相关性显著;有雨时,加勒比松日液流密度仅与饱和蒸汽压及湿度相关性显著;单株日耗水量变幅为6.4～169.5 L,日平均耗水量为55.5 L,林分日耗水量变幅为0.35～3.52 mm·d-1,日均耗水量为1.71 mm·d-1,旱季总耗水量为257.7 mm,占同期降水量的72.3%. 相似文献
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JIM SCHUMACHER DVM MS Diplomate ACVS DICKSON D. VARNER DVM MS Diplomate ACT DAVID G. SCHMITZ DVM MS Diplomate ACVIM TERRY L. BLANCHARD DVM MS Diplomate ACT 《Veterinary surgery : VS》1995,24(3):250-254
A urethral defect, presumed to communicate with the corpus spongiosum penis, caused hematuria in seven geldings and hemospermia in three stallions. Hematuria in geldings occurred at the end of urination. Hematuria was not observed in stallions with hemospermia. A linear urethral defect was identified, by endoscopic examination, on the convex surface the urethra at the level of the ischial arch of each horse. Cause of the defect was not determined. Two stallions were successfully treated for hemospermia, one by temporary subischial urethrostomy combined with sexual rest for 10 weeks, and the other by sexual rest alone for 6 months. The third stallion had hemospermia 6 weeks after urethrostomy. The geldings were successfully treated for hematuria, six by temporary subischial urethrostomy, and one by a subischial incision that extended into the corpus spongiosum penis but did not enter the lumen of the urethra. Efficacy of subischial urethrostomy for treatment of hemospermia was difficult to assess because of the small number of surgically treated stallions. In geldings, surgery eliminated hematuria, presumably by reducing vascular pressure in the corpus spongiosum penis during urination, thus allowing the urethral defect to heal. 相似文献
8.
The clinical, pathological and biochemical findings of a study of 30 Poll Hereford, Hereford, Poll Hereford cross or Hereford cross calves affected with branched chain ketoacid dehydrogenase (BCKAD) complex deficiency or maple syrup urine disease (MSUD) are presented. In breeding studies, 6 of 21 calves from obligate heterozygote matings were affected with MSUD, suggesting the disease is inherited in an autosomal recessive manner. Calves were clinically affected from birth, but there were variations in the subsequent course of progressive deterioration of central nervous system function. Concentrations of the branched chain amino acids and keto acids were elevated in pre-suckle plasma and cerebellar water content was higher in affected calves. Activity of BCKAD complex was minimal in fibroblasts cultured from an affected calf. Spongiform encephalopathy and elevated ratios of the branched to straight chain amino acids in formalin fixed cerebral tissue were found in a stillborn foetus and a 3-month-old Hereford calf. These findings suggest the disease occurs prenatally and that a delayed form may exist. 相似文献
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TROY S. FORD DVM Diplomate ACVS JIM SCHUMACHER DVM MS Diplomate ACVS MORGAN K. CHAFFIN DVM MS JOHN VACEK DVM GORDON W. BRUMBAUGH DVM PhD Diplomate ACVIM LAMAR E. CROSSLAND DVM 《Veterinary surgery : VS》1991,20(5):316-319
An intrathoracic esophageal pulsion diverticulum causing repeated episodes of esophageal obstruction in a Morgan weanling colt was diagnosed by endoscopy, positive contrast radiography, and pleuroscopy. Surgical excision of the diverticulum alleviated clinical signs, and the horse was able to resume a normal diet by day 6. After 9 months the colt remains asymptomatic. 相似文献
10.
Behaviour of trifloxystrobin and tebuconazole on grapes under semi‐arid tropical climatic conditions
Soudamini Mohapatra Ashok K Ahuja M Deepa GK Jagadish GS Prakash Sampath Kumar 《Pest management science》2010,66(8):910-915
BACKGROUND: A mixture of trifloxystrobin and tebuconazole is excellent in controlling both powdery and downy mildew of grapes. The objective of the present work was to study the behaviour of trifloxystrobin and tebuconazole on grape berries and soil following treatment with Nativo 75 WG, a formulation containing both fungicides (trifloxystrobin 250 + tebuconazole 500 g kg?1). This study was carried out for planned registration of this mixture for use on grapes in India. RESULTS: Initial residue deposits of trifloxystrobin and tebuconazole on grapes were below their maximum residue limit (MRL) of 0.5 and 2 mg kg?1, respectively, when Nativo 75 WG was applied at the recommended dose of 175 g product ha?1. The residues dissipated gradually to 0.02 and 0.05 mg kg?1 by 30 days, and were below the quantifiable limit of 0.01 mg kg?1 at the time of harvest (60 days after the last treatment). Trifloxystrobin and tebuconazole dissipated at a pre‐harvest interval (PHI) of 36 and 34 days, respectively, from the recommended treatment dose. The acid metabolite of trifloxystrobin, CGA 321 113, was not detected in grape berries at any point in time. Soil at harvest was free of any pesticide residues. CONCLUSION: Residue levels of both trifloxystrobin and tebuconazole were below MRLs when grapes were harvested 30 days after the last of four applications of 175 g product ha?1 (trifloxystrobin 44 g AI ha?1, tebuconazole 88 g AI ha?1) under the semi‐arid tropical climatic conditions of India. Copyright © 2010 Society of Chemical Industry 相似文献