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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

The aim of this study was to evaluate the relationship between cigarette smoking and the condition of the teeth and periodontium and the oral health behavior of 18-year-olds. Cross-sectional studies on 1,611 18-year-olds from Poland were conducted in 2017. The questionnaire provided socio-economic data, information about health-related behavior (cigarette smoking and oral health behavior), and absence from school due to oral pain. The dentition status (DMFT and DMFS), periodontal status (gingival bleeding, depth of periodontal pockets, loss of attachment), and need for endodontic treatment or tooth extraction were clinically assessed. Cigarette smoking was reported by 25% of participants (15% reported every day smoking). Adolescents who smoked cigarettes regularly had a higher mean number of decayed teeth (2.40±3.21 vs. 1.95±2.66) and similar periodontal status. Cigarette smoking increased the risk of oral hygiene neglect (63% vs. 69%), dietary mistakes (25% vs. 13%), failure to make dental appointments (32% vs. 43%), occurrence of oral pain (28% vs. 27%), absence from school due to pain (13% vs. 6%), and the need for endodontic treatment or tooth extraction (11% vs. 5%). The socio-economic factors and sex of the subjects decreased the influence of smoking only on oral hygiene neglect. Cigarette smoking by adolescents seems to be an independent risk factor for serious dietary mistakes, failure to benefit from oral healthcare, and more dynamic damage of teeth, which lead to pain and even tooth loss. Therefore, these aspects should be included in the risk assessment of oral disease and incorporated into educational programs promoting a healthy lifestyle.

Abstract

The argan tree is a multi-purpose tree (fruit tree, medicinal, cosmetic, and pastoral plant) found in the semi-arid and arid regions of North Africa. It is under strong human pressure such as the impact of population growth, crop expansion, overgrazing, and wood and fruit exploitation that are also the main causes of desertification in the rest of the world. Over the years, interest in this beneficial tree and demand for its products have increased: especially with the increase in the price of argan oil, which is now one of the most expensive and much in demand oils in the world. This increase has led to many socio-political, economic and cultural changes at the national, regional and local levels, especially in farming behaviour and the habits of the local population. This bibliographic research was therefore conducted in order to analyse the various changes and their consequences on the planning, conservation, and management methods implemented in the argan tree area and their effects on the habits of the local population in order to ensure the sustainability of the Argan Tree Biosphere Reserve in Morocco. Indeed, the aims of this study were, firstly, to analyse the change dynamic of argan forest area in the ABR; and secondly, to investigate the impact of various socio-political, economic and cultural changes resulting from increased prices of argan oil on planning, conservation, and management methods of argan tree ecosystem and on the habits of the local population.

Abstract

Over the years, it has been the subject of discussions whether efficiency-oriented interventions contribute to an equity distribution of wealth across regions and whether equity orientation is a source of inefficiency. While efficiency refers to the maximization of growth in the national economy, convergence-oriented policy is focused on equalizing the level of development at interregional level. The case of Georgia was studied as a developing country facing various challenges in terms of economic growth and regional divergence. This article provides an overview of the economic development trends taking place in the regions of Georgia and reveals the high level of divergence within the country. A logarithmic model was created and used to run simulations to predict the possible results of convergence-oriented policy in Georgia. In order to make the forecast we estimated GDP per capita and average growth rates in all the Georgian regions. Use of the model allowed us to answer two main questions: (1) If the last 5 and 10 year average growth rates are maintained, how long will it take for the poorest region to converge to the wealthiest one? (2) What should be the minimum growth rate in the poorest region for the upcoming 5, 10 and 20 years in order to converge to the wealthiest capital? Results of the calculations showed that convergence between regions can only be achieved by slowing down economic growth in relatively wealthier regions and by focusing on the development of the poorest ones. The results of the study revealed that the convergence process will be faster for the regions with medium or big cities and growth centres. Therefore, creating competitive growth centres would be a reasonable regional policy objective to promote fast economic growth and future convergence without redirecting the growth process from more developed areas to lagging ones.

Abstract

Ageing is one of the most complex and difficult problems for humans to face and for science to solve. Although human senescence was viewed as a passive and uncontrollable process of deterioration over time with little or no genetic regulation, the concept that ageing is caused by both genetic and environmental factors is now generally accepted, even though it remains difficult to distinguish between ageing sensu stricto and the effects of age-related diseases. Empirical data show that mechanisms of ageing are highly conserved during evolution. Moreover, it has been established that there are specific molecular ‘instructions’ for ageing, which suggests that a better understanding of the molecular biology of ageing will open new possibilities regarding future interventions. The complexity of ageing diminishes the possibility that any general theory will completely explain this metaphenomenon. Likewise, it is highly unlikely that any medication can stop or reverse human senescence. Nevertheless, ageing as a dynamic and malleable metaphenomenon can be modulated by a variety of influences. The concept of the shrinkage of the homeo-dynamic space with age, i.e. homeostenosis, is especially interesting and intriguing as it shows that novel therapeutic approaches and rational strategies can help delay the onset of the ageing-associated pathologies by enhancing the homeodynamic capabilities of the body. The aim of this article is to present current data from evolutionary and molecular gerontology and discuss them within the ambit of this review which is devoted to the dynamic, emergent and plastic nature of human ageing and implications for future interventions.

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.