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141.
It was shown that the use of a light-correcting film as a covering material for an oil-contaminated soil in combination with humic acids increased the number of the main physiological groups of the soil microorganisms responsible for the development of the soil’s fertility (heterotrophic bacteria, actinomycetes, and micromycetes) by 60–100 times. The activity of the soil enzymes (catalase, dehydrogenase, polyphenoloxidase, peroxidase, and urease) increased by 3–6 times. The biochemical oxidation of oil hydrocarbons in the soil became significantly more intense.  相似文献   
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Results of long-term studies in middle-taiga pine forests on sandy podzols after controlled surface fires are presented. The changes in the soil hydrothermal conditions caused by the pyrogenic transformation of the soil and the pyrogenic and postpyrogenic changes in other components of the forest biogeocenoses were revealed. Along with the general character of the changes in the soils’ hydrothermal conditions, some differences in the degree of their manifestation between different regions due to the different fire intensities were revealed. It was concluded that the pyrogenic impact disturbed the existing material and energy exchange between the atmosphere and the soil, which is the main process of soil formation and development. Consequently, forest fires are a powerful and active factor of recent pedogenesis.  相似文献   
144.
Inherited disorders of sexual development are important to identify as a cause of inherited infertility or sterility in humans and animals. Investigation of these disorders in dogs and cats can identify new mutations, allowing us to eliminate inherited disorders from breeding populations, while contributing to the understanding of mammalian sexual development and differentiation. This review updates an overview of normal mammalian sexual development while discussing disorders of sexual development at three consecutive levels, as errors in sex chromosome constitution, gonadal sex determination or phenotypic sexual development. The molecular mechanisms controlling sexual development and current molecular methods to identify causative mutations are illustrated in three specific examples of abnormal sexual development reported in small animals: XX sex reversal, Persistent Mullerian Duct Syndrome and cryptorchidism. Identification of causative mutations and development of practical tests to identify carrier and affected animals will provide effective mechanisms to reduce the prevalence of these disorders in small animals.  相似文献   
145.
The equatorial Medusae Fossae Formation (MFF) is enigmatic and perhaps among the youngest geologic deposits on Mars. They are thought to be composed of volcanic ash, eolian sediments, or an ice-rich material analogous to polar layered deposits. The Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) instrument aboard the Mars Express Spacecraft has detected nadir echoes offset in time-delay from the surface return in orbits over MFF material. These echoes are interpreted to be from the subsurface interface between the MFF material and the underlying terrain. The delay time between the MFF surface and subsurface echoes is consistent with massive deposits emplaced on generally planar lowlands materials with a real dielectric constant of approximately 2.9 +/- 0.4. The real dielectric constant and the estimated dielectric losses are consistent with a substantial component of water ice. However, an anomalously low-density, ice-poor material cannot be ruled out. If ice-rich, the MFF must have a higher percentage of dust and sand than polar layered deposits. The volume of water in an ice-rich MFF deposit would be comparable to that of the south polar layered deposits.  相似文献   
146.
The landscape approach to developing perennial grass cultivation practices made it possible to reveal ecologically homogeneous sections and to create the basis for organizing sustainable fodder production under the complex landscape conditions of the region. The adaptation characteristics of perennial grasses and their productivity are different in agromicrolandscapes characterized by the same geochemical association of relief features but on different hill slopes (southern and northern).  相似文献   
147.
The low incidence of cardiovascular disease in Mediterranean countries leads to an increased interest of the scientific community for the Mediterranean diet. Our aim was to evaluate total phenol and flavonoid contents, antioxidant capacity, free radical scavenging activity and potential antihypertensive effect of aqueous extract obtained from Thymus serpyllum L. (wild thyme, TE), an aromatic herb from the Lamiaceae family (highly present in Mediterranean diet), in spontaneously hypertensive rats (SHR) and in normotensive Wistar rats. Total phenol content of TE was 2008.33?±?10.6 mg/L GAE, and rosmarinic and caffeic acids were predominant phenolic compounds. The ferric reducing/antioxidant power and antioxidant capacity analysis revealed strong antioxidative properties of TE. In vitro nitric oxide-scavenging activity of 1 mg/l TE was 63.43 % with the IC50 value of 122.36 μg/ml. Bolus injection of TE (100 mg/kg body weight i.v.) induced significant decrease of systolic and diastolic blood pressure and total peripheral resistance in SHR, without effects on these parameters in normotensive Wistar rats. Cardiac index remained unchanged after TE treatment in all experimental rats. Given dose of TE did not show significant nitric oxide-scavenging activity in vivo. Our results indicate that TE may protect against hypertension in experimental model of essential hypertension.  相似文献   
148.

Background

It is generally accepted that controlled vocabularies are necessary to systematically integrate data from various sources. During the last decade, several plant ontologies have been developed, some of which are community specific or were developed for a particular purpose. In most cases, the practical application of these ontologies has been limited to systematically storing experimental data. Due to technical constraints, complex data structures and term redundancies, it has been difficult to apply them directly into analysis tools.

Results

Here, we describe a simplified and cross-species compatible set of controlled vocabularies for plant anatomy, focussing mainly on monocotypledonous and dicotyledonous crop and model plants. Their content was designed primarily for their direct use in graphical visualization tools. Specifically, we created annotation vocabularies that can be understood by non-specialists, are minimally redundant, simply structured, have low tree depth, and we tested them practically in the frame of Genevestigator.

Conclusions

The application of the proposed ontologies enabled the aggregation of data from hundreds of experiments to visualize gene expression across tissue types. It also facilitated the comparison of expression across species. The described controlled vocabularies are maintained by a dedicated curation team and are available upon request.
  相似文献   
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