44 research outputs found
Changes in the agrochemical parameters of sod-podzolic soils under the influence of chromium pollution and recultivation measures
In the conditions of the Udmurt Republic, field experiments (2017-2021) were carried out on the remediation of agro-podzolic loamy soil (albeluvisoils) with a high level of chromium contamination (application of 500 mg a.i./kg of soil). Both chemical and physicochemical mechanisms have been used to reduce the degree of mobility of this heavy metal in soil. Ameliorants and fertilizers (limestone and phosphate rock, superphosphate, potassium humate, peat, zeolite) in various doses were studied as ameliorative additives. Various doses of ameliorants and fertilizers were studied as ameliorative additives: limestone and phospharite meal, superphosphate, potassium humate, peat and zeolite. As a result of the research, it was found that all ameliorative additives not only caused a sharp decrease in the mobility of chromium by 40-65 %, but also had a positive effect on the agrochemical parameters of the contaminated soil. The nature and parameters of this influence were determined by their chemical composition, the rate of application, and the period that passed after the application. Limestone flour statistically significantly reduced soil acidity in contaminated soil (by 1.21-3.03 pHKCl units) and increased the total of absorbed bases by 1.7-6.5 times. Phospharite meal (by 2.1-9.1 times) and superphosphate (by 13-43 %) increased the mobile phosphorus content in the soil; peat increased the organic matter content (by 0.28-1.47 abs.%); zeolite increased the total exchangeable bases by 1.4-9.8 mmol/100g or by 12-239 %. The positive effect of these ameliorative additives, especially their increased doses, was traced during all five years of observation, what allows them to be recommended as promising ameliorants for restoring the fertility of soddy-podzolic soils contaminated with chromium
Some features of the hydrodynamic characteristics of a high-voltage electric discharge in a liquid with a two-pulse power deposition law
Hydrodynamic Characteristics of the Electric Discharge in the Liquid at Energy Supplied to the Channel in a Form of Repeating Pulses
Subglacial and Seabed Topography, Ice Thickness and Water Columm Thickness in the Vicinity of Filchner-Ronne-Schelfseis, Antarctica
The seabed morphology beneath the ice shelf is dominated by a slope down towards the interior of the continent. Deep troughs, possibly glacially deepened, run beneath the eastern and weatern sides of the ice shelf and cross the continental shelf. An area of small water column thickness to the north-west of Berkner Island suggests that extensive grounding could occur after a relatively small change in the ice shel
Distribution of antigens of the HLA-system in married couples with reproductive disorders
Aim: to study the distribution of HLA-antigens in married couples with failed conception and/or carrying of pregnancy, and to assess the occurrence rate and the presence of common alleles of the main histocompatibility complex in couples with infertility and miscarriages.Materials and methods. We conducted HLA-typing of 198 married couples with aggravated obstetric history. The main inclusion criteria were conception failures and unsuccessful outcomes of previous pregnancies. The HLA-class I antigen typing was carried out using a standard micro-lymphocyte-toxic test («Gisans», Russia); for the class II HLA-antigens, real-time polymerase chain reaction («DNA-Technology», Russia) was used. Based on the obstetric and gynecological history, the patients were divided into 2 subgroups: 1st – those with infertility and 2nd– with recurrent miscarriages. The comparison group included 101 married couples with no aggravated obstetric history, no infectious, no endocrine or anatomical abnormalities, and having 2 or more children. The occurrence rates of classes I and II HLA-antigens in women and men from the examined groups were compared with those in healthy individuals living in the same area.Results. In the examined couples with recurrent miscarriages, the HLA-A11 antigen occurred significantly more often in men, and HLA-В35 antigen – less often in women. In women of the infertile couples, HLA-A19 antigen was detected more often than in couples with children. In women with infertility, the HLA-DRB1*08 and HLA-DQA1*0401 alleles were less common than in women without fertility disorders. In the examined couples with infertility and recurrent miscarriages, statistically significant predominance of 3 genes common to the HLA class II system was found. In couples with normal fertility functions, the absence of homologous alleles of the HLA class II system in their genotypes was typical.Conclusion. HLA typing allows for predicting the risk of infertility and reproductive failure