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Summary

Preliminary studies which may be of significance for research against coronaviruses, including SARS-CoV-2, which has caused an epidemic in China, are presented. An analysis was made of publicly available data that contain information about important metabolites neutralizing coronaviruses. Preliminary studies show that especially Ficus, barley, thistle and sundew should be additionally tested with the aim of producing medicines for coronavirus.

Abstract

Ultrafiltration of skim cow’s milk with a UF10-PAN membrane at volume reduction ratios (VRRs) of 2 and 3 was performed. The ultrafiltration retentates obtained were used for production of probiotic yoghurts with three different starters. A control sample was prepared using skim cow’s milk. All yoghurts were analysed according to the following parameters: titratable acidity, dry matter, organoleptic characteristics, number of specific microorganisms (Lactobacillus bulgaricus and Streptococcus thermophilus) and the total count of viable lactic acid bacteria for 28 d of storage. The results showed that the increase in the VRR during ultrafiltration increased the titratable acidity, as well as the dry matter of all yoghurts. Ultrafiltration concentration led to an increase in the count of viable lactic acid bacteria in all yoghurts which improved their functional properties. The highest values of the total number of viable lactic acid bacteria were determined in yoghurts obtained with starter 1CM, followed by starters MZ2 and ZD for both VRRs. Probiotic yoghurts with the highest organoleptic evaluation were obtained from ultrafiltration retentates at VRR = 2 and starters 1CM and MZ2.

Abstract

A total of 558 specimens of black-bellied anglerfish Lophius budegassa (Spinola, 1807) were collected by the vessels engaged in commercial trawl fishing in the Central Aegean Sea between September 2017 and August 2018 in order to determine age and growth. Ageing was based on growth ring counts of transverse sections of the illicium (first ray of the dorsal fin). By reading the illicium, individuals were found within II-XI age groups. Total lengths and weights ranged between 12.0 – 65.0 cm and 24.5 – 4682.0 g, respectively. Von Bertalanffy growth parameters were estimated for males, females and combined sexes of L. budegassa. The results are compared with previous studies.

Abstract

The properties of biomass-based fuel and combustion tests showed that logging residues are promising renewable energy sources. The data used in this study were collected from four clear-felling areas in Järvselja Training and Experimental Forest Centre, Southeast Estonia in 2013–2014. Logging was carried out by harvesters in Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies [L.] Karst.), silver birch (Betula pendula Roth.) and black alder (Alnus glutinosa L. Gaertn.) dominated stands with a small admixture of other tree species according to the cut-to-length method and logging residues were placed in heaps. The aim of this research is to assess different characteristics of logging residues (quantity, moisture content, energetic potential, ash content and amount) in clear-felling areas. The highest load of slash was measured on the birch dominated study site, where the dry weight of the logging residues was 29 t ha−1. Only the branch fraction moisture content on the black alder dominated site (35.4%) was clearly different from respective values on other sites (21.6–25.4%). The highest calorific value of the residues was assessed with the residues from the birch dominated site, where in moist sample it was 365 GJ ha−1 and in dry matter 585 GJ ha−1. The heating value of the fresh residues is highest in coniferous trees. The highest ash content in branch segments was registered for the black alder dominated site. Järvselja data indicate higher quality in conifer dominated sites, yet a higher load of logging residues in broadleaf dominated stands.

Abstract

This study focused on the occurrence of xylophagous beetles and nematodes in the different parts of Pinus sylvestris L. trees of different health condition in the pure stands in Zhytomyr region (Central Polissya). Stem fragments with thin, thick and transitional bark, branches and twigs were examined in each of 12 model trees. Xylophagous beetles were identified by adults or by galleries. Nematodes were isolated from wood samples in the laboratory using the Baermann method and identified by morphometric characteristics. Among 10 species of xylophagous beetles, Ips acuminatus (frequency 16.7%; dominance 17.9%) and I. sexdentatus (frequency 11.1%, dominance 54.6%) dominated, which prefer the fragments with thin and thick bark respectively. No xylophagous beetle was found in the healthy and slightly weakened trees. Among 15 nematode species, 40% were saproxylic, 33.3% entomophilic, 13.3% phytophagous, and by 6.7% predators and species associated with fungi. An entomophilic nematodes Cryptaphelenchus macrogaster f. acuminati was common in all parts of stem and branches (frequency of occurrence 25–33.3%). An entomophilic nematodes Parasitorhabditis acuminati and a predator Fuchsia buetschlii acuminati had the highest frequency of occurrence (41.7%) under the thin bark and in the branches. The frequency of these species in colonized with xylophagous insects stem fragments with thin bark was significantly higher than in respective not colonized fragments.

Abstract

There is a significant lack of data for the biological parameters of beluga or great sturgeon, the largest fish in the Caspian Sea. The age, growth and fisheries indices for the stock status of beluga was investigated in the south Caspian Basin of Iran between 1990 and 2011. Fork lengths ranged between 113-420 cm and weights from 8.0 to 725.0 kg. The growth parameters were L = 440 cm, K = 0.027 year−1, t 0 = − 5.8 years. The age at first capture (t c) was 13.1 years. The long-term age composition data showed age up to 63 years, and the ages 12-19 years comprised 76.7% of the total catch. The generation length was 33 years. The values of “KF” were close to 1 or >1, indicating that beluga sturgeon is in a favorable condition in the southern Caspian Sea. The length distribution showed that 24.2% of the catch is comprised of juveniles. Based on the age structure and age at first maturity, recruitment and growth overfishing occurred in beluga stocks. Therefore, increased length or age at first capture in future fishery policies should be implemented. The mega-spawners represented 4.4% of the fish captured and revealed an unhealthy population structure.

Abstract

Growth of forest plantations on soils causes changes in their properties. These changes, their behavior, and magnitude depend on the original soil characteristics and also on the effect of forest plantations being grown. In the steppe zone of Ukraine, Robinia pseudoacacia L. and Quercus robur L. are the woody species most widely used in planting of forest plantations on chernozem soil. Chernozem soil formed exclusively under zonal steppe vegetation and chernozem soil under Robinia pseudoacacia and Quercus robur plantations were studied in this work to analyze the changes in soil properties caused by growth of these tree species. Dry aggregate size distribution, density, particle density, total porosity, organic carbon content, cation exchange capacity, pH values, hydrolytic soil acidity and dry residue, and the available nitrogen, phosphorus, and potassium content were analyzed. The studies found that Robinia pseudoacacia and Quercus robur plantations contribute to an increase in the share of aggregates 2–1 mm in size, as well as formation of aggregate fraction >10 mm, which are completely absent in the Calcic chernozem developed under the steppe vegetation. An increase in the density and particle density, as well as a decrease in the total porosity values were observed under the influence of forest stands studied. This is more common with chernozem under Q. robur plantation. It was found that the carbon percentage decreased in chernozem under the influence of Robinia pseudoacacia growth (on average, 0.4% by a meter-deep layer), but under Quercus robur planting it increased (on average 0.3% by meter-deep layer). Effect of Robinia pseudoacacia plantings on chernozem was also manifested by a decrease in cation exchange capacity (on average, 11 cmol/100 g by a meter-deep layer). The growth of R. pseudoacacia and Quercus robur plantations results in decrease of pH values (0.2 by a meter-deep layer) and increase of hydrolytic soil acidity and dry residue in chernozem water extract. Effect of Robinia pseudoacacia planting leads to a decrease in carbon, nitrogen, and phosphorus content in chernozem. The change in chernozem properties under the influence of Quercus robur plantation is reflected in accumulation of these nutrients. Growth of Robinia pseudoacacia and Quercus robur plantations leads to a decrease in potassium reserves in chernozem, which may indicate its active uptake by these woody species. In general, Q. robur planting is characterized by a large positive effect on the physical and chemical properties of chernozem than Robinia pseudoacacia planting. The findings obtained serve as a ground for making a recommendation for growing Quercus robur plantations under climate conditions of the steppe zone of Ukraine in order to improve the zonal chernozems’ state and fertility.

Abstract

Norway spruce (Picea abies [L.] Karst.) and silver fir (Abies alba Mill.) are main tree species of Central Europe that are currently highly vulnerable in times of global climate change. The research deals with the effect of climate and air pollution on radial growth of silver fir and Norway spruce in mixed age-varied (56 – 146 years) forests in the Jeseníky Protected Landscape Area, the Czech Republic. The objectives were to evaluate biodiversity, structure and production, specifically interaction of radial growth of fir and spruce to air pollution (SO2, NOX, tropospheric ozone) and climatic factors (precipitation, air temperature). Concentration of SO2 and NOX had negative effect on radial growth of fir, while radial growth of spruce was more negatively influenced by tropospheric ozone. Fir showed higher variability in radial growth and was more sensitive to climatic factors compared to spruce. On the other hand, fir was relatively adaptable tree species that regenerated very well when the pressure of stress factors subsided (air pollution load, Caucasian bark beetle, frost damage). Low temperature was a limiting factor of radial growth in the study mountainous area, especially for fir. Fir was significantly sensitive to late frost, respectively, spruce to winter desiccation and spring droughts with synergism of air pollution load. Generally, older forest stands were more negatively influenced by air pollution load and climatic extremes compared to young trees.

Abstract

This study investigated the efficacy of Tamarind Leaves (TL) and Mango Leaves (ML) with Oxytetracycline (OXY) on growth performance, haematoimmunological and disease resistance of Clarias gariepinus juveniles against Aeromonas hydrophila. Experimental diets consist of control (0%), TL2 (1%), TL3 (2%), ML4 (1%), ML5 (2%), OXY6 (30mg/kg diet), (TL+ML) 7, (TL+OXY) 8, (ML+OXY) 9 and (TL+ML+OXY) 10. The fish (3.02±0.01g) were replicated twice with 20 fish per replicate and were fed twice daily at 3% body weight of 40% crude protein for twelve weeks (8 weeks for feeding trial and 4 weeks for challenge test). Mean Weight Gain (MWG), Specific Growth Rate (SGR), Packed Cell Volume (PCV), Haemoglobin (Hb), Lymphocytes (LYM), Globulin (GLO), Amino Alanine Transferase (ALT) and Aspertate Amino Transferase (AST) contents were ascertained using standard technique. The fish were infected with A. hydrophila at 5.94 log10 CFU/ml interperitoneally and fed different diets to evaluate their Relative Percent of Survival (RPS). Data was subjected to descriptive statistics and one-way analysis of variance at P=0.05. Clarias gariepinus juveniles fed treated diets had higher growth rates than the control diet but C. gariepinus fed (TL+ML+OXY) 10 had a significantly higher MWG and SGR of 7.74±0.69 g and 0.97±0.01 g, respectively. The PCV (44.0±2.00%), Hb (14.7±2.00 g/dl), LYM (37.0±2.00), GLO (42.0 ±2.00 g/dl) were higher in the C. gariepinus fed (TL+ML+OXY) 10 than the control diet. The AST and ALT values among the treated groups were lower than the values in the control at the post-challenge test. The RPS against A. hydrophila was higher in the treated groups (100%) than in the control (0%). Fish fed tamarind and mango leaves had enhanced mean weight gain and were more resistant to A. hydrophila infection.

Abstract

Loss of fish biodiversity, especially in the inland and coastal areas, is a major concern in sustainable fish production. Indiscriminate fish catch, climate change and many other anthropogenic activities synergistically affect fish biodiversity. To formulate a sustainable fish biodiversity conservation plan, fish biodiversity in the Andharmanik River, a 40-km-long Hilsa shad sanctuary in the southern part of Bangladesh, was assessed. The study was conducted to understand the status of fish species diversity through sampling in three sampling stations between December 2014 and November 2015. A total of 93 fish species were found belonging to 66 genera, 45 families and 14 orders. Perciformes (27.65%) was found to be the most dominant order, followed by Cypriniformes (20.21%), Siluriformes (21.28%) Clupeiformes (7.45%) Mastacembeliformes (4.26%) and Channiformes (4.26%). Out of the 93 fish species of the river, the percentage compositions of the vulnerable, endangered, critically endangered and not threatened were found to be 14%, 11%, 6% and 59%, respectively. Four population indices viz. Shannon-Wiener’s diversity index (H), Simpson’s dominance index (D), Simpson’s index of diversity (1-D) and Margalef’s index (d) were applied to demonstrate species diversity, richness and evenness of fish species in sampling areas, and the overall values of the indices were 2.70-3.51, 0.10-0.12, 0.88-0.90 and 7.84-8.19, respectively. The main threats to fish biodiversity were reviewed and the measures for fish biodiversity conservation of the river recommended. Indiscriminate fishing using biodiversity destructive gears, as well as losing hydrological and ecological connectivity with the surrounding habitats, were identified as major threats to biodiversity in the Andharmanik River. Effective sanctuary-based co-management, immediate actions for habitat enhancement to conserve and improve fish biodiversity in the river were recommended. Necessary steps to improve hydrological and ecological connectivity for habitat protection and elimination of all destructive fishing gears in order to conserve biodiversity in the Andharmanik River were also suggested.