Search results for "Interest"
showing 10 items of 624 documents
Pest Plant Score of Alien Robinia Pseudoacacia in Rīga (Latvia) and Kaunas (Lithuania) / Svešzemju Sugas Robinia Pseudoacacia Invazitātes Novērtējums…
2015
Abstract Robinia pseudoacacia is an alien tree species that has wide distribution in green areas of Rīga and Kaunas. In recent years, the spread and invasion of this species was observed. The aim of this study was to determine the relative importance of invasiveness of R. pseudoacacia in Rīga and Kaunas. The degree of species invasion was estimated by applying the Pest Plant Prioritization Process, which is based on the Analytic Hierarchy Process method. The results showed that the invasive degree of R. pseudoacacia was near medium (0.4); the present compared to potential distribution rating was medium (0.57) and the social, environmental and economic impact score was very low (0.17). The F…
Macro and Trace Elements in Barley (Hordeum vulgare L.) Breeds in Latvia Depending on Variety, Environment, and Agricultural Practice
2018
Abstract The aim of the study was to determine concentrations of 13 macro and trace elements in different barley genotypes depending on the year of growth (2011, 2012, and 2013) and agricultural practice (conventional/organic). Cd, Pb, Cr, Ni, and Al concentrations were determined by electrothermal atomic absorption spectrometry and K, Na, Zn, Cu, Ca, Mg, Mn, and Fe concentrations by flame atomic absorption spectrometry. Statistically different concentrations of Cr, Cu, and Zn occurred among genotypes; for Ca, Mn, and Fe concentrations between barley grains, grown conventionally and organically; for Cr and Ni concentrations between hulled and hull-less grain and for Cd, Cr, Ni, Cu, Zn, Al, …
Microbial Food Web Components as Potential Indicators of Urban Hydroecosystems / Mikrobiālās ķēdēs Komponentu Potenciāls Pielietojums Urbānās Vides Ū…
2015
Abstract Assessment of the effect of urbanisation on biodiversity and ecological impact studies are focused on plants, birds, terrestrial arthropods, and relatively few studies have been on aquatic organisms. The aim of this study was to investigate the microbial food web components as potential indicators of the trophic state of two small natural lakes (Gaiļezers, Bābelītis), two artificial lakes or reservoirs (created after excavation activities before 20 years) and the Gulf of Riga seaside Vecāķi beach (littoral), all of which are located in the city of Riga or close to it. Analysis of samples was conducted from April til October 2014 by epifluorescense microscopy for pico and nanoplankt…
Use of Flow Cytometry for Producing Tetraploids in Red Clover
2020
Abstract Sprouts of diploid red clover ‘Stendes Agrais’ were treated with 0.2% colchicine solution. The ploidy level of plants was detected by flow cytometry. Most of the treated plants were mixoploids and sterile. From progenies of fertile plants, mixoploids were selected that had a proportion of tetraploid cells higher than 60%. In the next generation, stable tetraploid plants were selected, and 49 lines were included in the breeding process.
Concentration of Potentially Toxic Elements in Various Berries Grown in Allotment Gardens of Rīga City, Latvia
2017
Abstract Concentration of trace and major elements is an important indicator of nutritional value of food, also regarding cultivated food crops like fruits, berries, and vegetables. Concentration of elements differs regionally and is influenced by various factors. Nevertheless, some chemical elements (As, Cd, Hg, Ni, Pb, Zn, etc.) are known as environmental pollutants and may affect the quality and safety of crops and food products. The aim of the study was to determine the concentration of potentially toxic elements like Cd, Cr, Cu, Fe, Ni, Pb, and Zn in samples of berries grown in allotment gardens of Rīga city. Dried and homogenised samples of raspberries, strawberries, red currants, bla…
Association between Inflammatory Markers and Clinical and Metabolic Risk Factors for Cardiovascular Diseases
2009
Association between Inflammatory Markers and Clinical and Metabolic Risk Factors for Cardiovascular Diseases The inflammatory reaction plays an important role in the development of atherosclerosis. The clinical significance of the main inflammatory markers — C-reactive protein (CRP), interleukin 6 (IL6), tumour necrosis factor alpha (TNF-α), plasminogen activator inhibitor 1 (PAI1), etc. — has not been fully established. CRP, IL6, TNF-α, and PAI1 were assessed in 100 patients in terms of certain clinical indicators (sex, obesity indicators, blood pressure, and heart rate), total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C), trig…
Enzymatic Hydrolysis of Lignocellulose for Bioethanol Production
2017
Abstract The effect of temperature, time and amount of enzyme on hydrolysis of wheat straw lignocellulose remaining after furfural production was studied. The residual substrate was subjected to enzymatic hydrolysis at different temperatures — 45 °C, 50 °C and 55 °C. Hydrolysis time was 72 hours, and samples were taken every 24 hours. The maximum glucose yield (76.5% of the theoretically possible) was reached when hydrolysis temperature 50 °C was used. The production rate of glucose increased with a hydrolysis period of time. The yield of glucose significantly depended on the ratio of enzyme to substrate.
Visual Acuity in Myopes with Standard and Reversed Contrast Optotypes
2017
Abstract The aim of this study was to assess the visual acuity of myopes with standard and reversed contrast optotypes and to determine how the visual acuity of myopes is affected by optical defocus and the type of optical correction, either contact lenses or spectacles. Twenty-three myopic subjects (18 and 23 years old) with uncorrected vision had their visual acuity assessed with both standard and reversed contrast optotypes. The study also included 10 myopes with contact lens as well as habitual spectacle correction. The visual acuity for myopes with uncorrected vision was better with reversed than standard contrast optotypes. Better reversed contrast than standard contrast visual acuity…
Effect of Lignin-Containing Media on Growth of Medicinal Mushroom Lentinula Edodes
2017
Abstract The effect of lignocellulose and lignin on growth of mycelium of mushroom Lentinula edodes and laccase activity in cultivation medium was studied. It was shown that cultivation of L. edodes mycelium in liquid nutrient medium with addition of 0.25-0.5% of kraft lignin increased mycelium biomass yield approximately two times compared with reference conditions without addition of lignin. Similar results were obtained in experiments in which 0.5% lignocellulose that remained after obtaining furfural, and 0.5% lignin that remained after obtaining furfural and glucose from wheat straw, were added to the nutrient medium. This effect was greater in the conditions of cultivation with good a…
Use of Quantitative Morphological Analysis Combined with a Large Sample Size for Estimating Morphological Variability in a Case Study of Armoured Mit…
2015
Abstract The morphology of Oribatida and similar little-known groups of organisms varies considerably, which complicates morphological analysis (e.g. species descriptions). Qualitative analyses have been carried out mostly on a small number of individuals (n < 25). There is lack of studies dealing with mechanisms of how that variation can change in relation to sample size and insufficient discussion on whether qualitative or quantitative analysis is more appropriate for description of morphological variability. A total of 500 adult Carabodes subarcticus Trägårdh, 1902 Oribatida were collected from a local population. Six qualitative and six quantitative traits were characterised using li…