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41.
Antonio J. Romero-Baena Isabel González Emilio Galán 《Journal of Soils and Sediments》2018,18(6):2231-2247
Purpose
Geochemical and mineralogical studies of soils potentially polluted by trace elements are basic to find the source of pollution, to understand the behavior of the contaminants in the environment, and to propose remediation and reclamation actions. This work reviews the role of the Mineralogy and Geochemistry to assess the hazard of soil contamination by trace elements in mining areas, focusing on three different case studies carried out in the Andalusian community (South Spain), with a Mediterranean temperate climate.Materials and methods
Two significant mining districts were selected for this work: the Linares-La Carolina (Pb-Zn ores) and the Riotinto (Iberian Pyrite Belt, IPB) mining areas. Another case study was the Guadiamar basin, which soil was polluted by the spill produced in 1998 by the breakage of a mine tailing impoundment in Aznalcóllar mines (IPB). Soils, mine waste, and secondary precipitates were studied to approach the source of the pollution and the fate of the contaminants. Chemical composition (major and trace elements), soil parameters, and mineralogy of all materials selected were studied. In addition, the bioavailability of trace elements was determined by different methods.Results and discussion
Pyrite and secondary phases are the main sources of pollution in the Riotinto area. Their stability is a key factor in the release of trace elements. The availability of trace elements in soils was lower in unpolluted leptosols than in contaminated orchards. In Linares-La Carolina, a severe pollution by Pb and a high availability (10–70% extracted with EDTA) were found. In Guadiamar basin, the residual pyrite sludge continues releasing trace elements to soil. Cd and Zn were mobile at pH <?6 and As at pH >?8, and Pb was quite immobile. Cd, Zn, and Pb can be coprecipitated by carbonates while As is mainly adsorbed by clays and iron oxyhydroxides.Conclusions
The geochemical studies of soils polluted by mining activities allow to evaluate the availability of trace elements and their retention in soils. Therefore, geochemical and mineralogical studies are necessary for the assessment of soil pollution and remediation actions.42.
Galán A Guil-Luna S Millán Y Martín-Suárez EM Pumarola M de Las Mulas JM 《Veterinary and comparative oncology》2010,8(4):254-262
Gliomatosis cerebri (GC) is a rare, diffusely infiltrating, glial cell tumour of neuroepithelial origin. This report describes a case of oligodendroglial GC in a 6-year-old male Poodle with central nervous system symptoms. Computed tomography revealed anomalous parenchyma density and ventricular asymmetry. Cerebrospinal fluid showed elevated protein (30 mg dL(-1)) and nucleated cell count (20 μL(-1)). Presumptive diagnosis of necrotizing meningoencephalitis was made. Because of rapid deterioration of the general condition of the animal, the dog was euthanized. Histologically there was an infiltration of round or ovoid neoplastic cells in the white matter of the left cerebral hemisphere and in leptomeninges. Immunohistochemistry showed that 80% of the neoplastic cells expressed Olig2 and some 50% expressed glial fibrilary acidic protein. On the basis of clinical, histological and immunohistochemical features, a diagnosis of oligodendoglial GC was done. This case represents the first report of a case of oligodendroglial GC in the canid. 相似文献
43.
在南京夏播条件下,研究华南四省区大豆地方品种群体主要农艺和品质性状的遗传特点、选择潜力和性状相关、华南群体具有植株高、粒小、蛋白质含量高、油分含量低、产量低等特点。百粒重、产量遗传变异丰富,选择潜力大;品质性状遗传变异小,选择潜力有限。全生育期是遗传变异中的最主要成分性状,且以全生育期进行的动态聚类分析分成的三类,有按春、夏、秋(冬)品种自然分类的趋势.产量与蛋白质含量负相关,与油分含量无显著相关;蛋白质含量与油分含量无显著相关。 相似文献
44.
Kelmer G Keegan KG Kramer J Wilson DA Pai FP Singh P 《American journal of veterinary research》2005,66(4):646-655
OBJECTIVE: To characterize compensatory movements of the head and pelvis that resemble lameness in horses. ANIMALS: 17 adult horses. PROCEDURE: Kinematic evaluations were performed while horses trotted on a treadmill before and after shoe-induced lameness. Lameness was quantified and the affected limb determined by algorithms that measured asymmetry in vertical movement of the head and pelvis. Induced primary lameness and compensatory movements resembling lameness were assessed by the Friedman test. Association between induced lameness and compensatory movements was examined by regression analysis. RESULTS: Compensatory movements resembling lameness in the ipsilateral forelimb were seen with induced lameness of a hind limb. There was less downward and less upward head movement during and after the stance phase of the ipsilateral forelimb. Doubling the severity of lameness in the hind limb increased severity of the compensatory movements in the ipsilateral forelimb by 50%. Compensatory movements resembling lameness of the hind limb were seen after induced lameness in a forelimb. There was less upward movement of the pelvis after the stance phase of the contralateral hind limb and, to a lesser extent, less downward movement of the pelvis during the stance phase of the ipsilateral hind limb. Doubling the severity of lameness in the forelimb increased compensatory movements of the contralateral hind limb by 5%. CONCLUSIONS AND CLINICAL RELEVANCE: Induced lameness in a hind limb causes prominent compensatory movements resembling lameness in the ipsilateral forelimb. Induced lameness in a forelimb causes slight compensatory movements resembling lameness in the ipsilateral and contralateral hind limbs. 相似文献
45.
OBJECTIVE: To evaluate pelvic movement over a large number of strides in sound horses and in horses with induced hind limb lameness by applying methods to the pelvis that have been described for evaluating vertical head movement in horses with induced forelimb lameness. ANIMALS: 17 adult horses. PROCEDURE: Horses were filmed while trotting on a treadmill before and after induction of transient mild and moderate hind limb lamenesses. Vertical pelvic movement was measured by a signal decomposition method. The vertical pelvic signal was decomposed into a periodic component (A1) that occurred at half the stride frequency (representing vertical pelvic movement caused by lameness) and another periodic component (A2) that occurred at stride frequency (representing normal vertical pelvic movement of a trotting horse). Vertical pelvic and foot positions were correlated for each stride to compare the difference between the minimum and maximum heights of the pelvis during and after stance of the right hind limb to the minimum and maximum heights of the pelvis during and after stance of the left hind limb. RESULTS: Maximum pelvic height difference and lameness amplitude (A1) differed significantly between sound and mild or moderate hind limb lameness conditions. Mean A1 value for vertical pelvic movement in sound horses was less than that previously reported for vertical head movement. CONCLUSION AND CLINICAL RELEVANCE: Pelvic height differences and signal decomposition of pelvic movement can be used to objectively evaluate hind limb lameness in horses over a large number of strides in clinical and research settings. 相似文献
46.
Gal Sapir Raphael A. Stern Sharoni Shafir Martin Goldway 《Scientia Horticulturae》2008,116(4):394-398
Japanese plum belongs to the Rosaceae, which carry the S-RNase-based gametophytic self-incompatibility system. Therefore, these plum cultivars depend on cross-pollination for setting fruit. However, cultivar combinations may be genetically semi- or fully compatible. In apples and pears cultivated in Israel, where conditions for pollination are usually unfavorable, it was demonstrated that yields may be correlated with compatibility levels of pollinators. In the present study fruit-set of semi- and fully compatible plum couples was determined for a wide range of cultivars, in unfavorable and favorable conditions. Full compatibility was found superior to semi-compatibility, in both unfavorable and favorable conditions for pollination. These findings should be taken into consideration in determining the orchard designs of cultivars. 相似文献
47.
I.J. Wilson R.K. Burchell A.J. Worth S.E. Burton K.R. Gedye K.J. Clark K.R. Crosse M. Jack T.F. Odom S.J. De Grey K.M.S. McGlade S.C. Tomlin N. Lopez‐Villalobos A. Gal 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2018,32(1):157-164
Background
Cell‐free DNA (cfDNA) comprises short, double‐stranded circulating DNA sequences released from damaged cells. In people, cfDNA concentrations correlate well with disease severity and tissue damage. No reports are available regarding cfDNA kinetics in dogs.Objectives/Hypothesis
Cell‐free DNA will have a short biological half‐life and would be able to stratify mild, moderate, and severe tissue injury. Our study aims were to determine the kinetics and biological half‐life of cfDNA and to contrast them with those of creatine kinase (CK).Animals
Three groups of 10 dogs undergoing open ovariohysterectomy, surgery for cranial cruciate ligament rupture (CCLR), or hemilaminectomy.Methods
Plasma for cfDNA and CK analysis was collected at admission, at induction of anesthesia, postsurgery (time 0) and at 6, 12, 24, 36, 48, 60, and 72 hours after surgery.Results
The biological half‐life of plasma cfDNA and CK were 5.64 hours (95% confidence interval [CI 95], 4.36–7.98 hours) and 28.7 hours (CI95, 25.3–33.3 hours), respectively. In the hemilaminectomy group, cfDNA concentrations differed significantly from admission at 6–12 hours after surgery. Creatine kinase activity differed among the surgical groups and reached a peak 6 hours after surgery. In the ovariohysterectomy and CCLR groups, plasma CK activity 72 hours after surgery did not differ from admission activity of the ovariohysterectomy group. In contrast, in the hemilaminectomy group, plasma CK activity after 72 hours did not return to the ovariohysterectomy group admission activity.Conclusions and Clinical Importance
Plasma CK activity has a longer biological half‐life than previously thought. In contrast to plasma CK activity, cfDNA has a short half‐life and could be a useful marker for peracute severe tissue injury. 相似文献48.
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