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Diversity and distribution of the spiders (arachnida: araneae) from Kailashahar: first record of nine species from Tripura, India
Get PDFSpiders are one of the most diverse and numerically abundant arthropods. They have a wide distribution and inhabit different types of habitats. Their occurrence and distribution function as a bio-indicator of that area and their presence is influenced greatly by the corresponding habitat and vegetation types. In this study the spider fauna was surveyed from November 2019 to October 2020 in three locations of Kailashahar, Tripura, India. A total of thirty-two species belonging to thirteen families and eighteen genera were identified. Among them nine species are reported for the first time in Tripura, India - Neogeo nocticolor, Tetragnatha mandibulata, Tetragnatha javana, Enoplognatha sp., Oxytate sp., Carrhotus viduus, Thalassius albocinctus, Scytodes fusca and Mimetus sp. The highest numerically abundant spider recorded is Oxyopes scalaris and the least abundant species is Opadometa fastigata in the study area. The present study thoroughly investigated the unexplored spider species distributed over the study area and highlights the richness of spider diversity while calling for greater conservation of forest areas. Further rigorous works are necessary to discover more new spider species from this unexplored state of northeast India.O
Environmental and Genetic Traffic in the Journey from Sperm to Offspring
Get PDFRecent advancements in the understanding of how sperm develop into offspring have shown complex interactions between environmental influences and genetic factors. The past decade, marked by a research surge, has not only highlighted the profound impact of paternal contributions on fertility and reproductive outcomes but also revolutionized our comprehension by unveiling how parental factors sculpt traits in successive generations through mechanisms that extend beyond traditional inheritance patterns. Studies have shown that offspring are more susceptible to environmental factors, especially during critical phases of growth. While these factors are broadly detrimental to health, their effects are especially acute during these periods. Moving beyond the immutable nature of the genome, the epigenetic profile of cells emerges as a dynamic architecture. This flexibility renders it susceptible to environmental disruptions. The primary objective of this review is to shed light on the diverse processes through which environmental agents affect male reproductive capacity. Additionally, it explores the consequences of paternal environmental interactions, demonstrating how interactions can reverberate in the offspring. It encompasses direct genetic changes as well as a broad spectrum of epigenetic adaptations. By consolidating current empirically supported research, it offers an exhaustive perspective on the interwoven trajectories of the environment, genetics, and epigenetics in the elaborate transition from sperm to offspring.O
The role of geometry precision in frequency-resonance method for non-destructive wood assessment - numerical case study on sugar maple
Get PDFThe application of frequency-resonance method (FRM) for precise log bending testing is limited by complex geometry; usually the cone with variable cross. This case study presents the relationship among non-destructively tested material parameters of sugar maples and the numerical analysis of effect of simplifications in FRM. Four standing stems were measured to find basic geometry parameters, 3D scanned for precise geometry description, tested by pulling test (PT) to obtain elastic parameters, and, finally, cut down to process the logs. Four logs were measured by stress wave propagation (SWP) using an acoustic tomography (AT) device to obtain longitudinal sound velocities and then evaluated by the FRM to obtain natural frequencies in bending and longitudinal vibrations. Comparison was made between the dynamic moduli of elasticity (MOE), calculated from SWP and the FRM, and the static MOE calculated from the PT. In-situ experimental evaluation was accompanied by modal analysis by finite element method (FEM) working at three levels of geometry simplification (beam model, simplified solid model, and scan-based solid model); the natural frequencies of bending and longitudinal mode shapes were analyzed. The influence of geometry precision on the resulting dynamic response of logs was found regarding comparison to the experimental values.OA-hybri
The importance of local faunal research of moths for plant protection: an example from an agricultural landscape in central Europe
Get PDFThe study was carried out in the agricultural landscape (mosaic of an urban environment, gardens, grassland, fields, small forests and semi-natural non-forest habitats) in central Europe (southeast Czechia) in 2021. A light trap was used for trapping (207 nights). A total of 485 moth species and 5 170 individuals were captured. Eurytopic species dominated the area, 72% of species and 89% of individuals. Fifty-nine species are considered pests (12%), representing 25% of individuals. The seasonal dynamics of selected harmful species were evaluated and discussed. Species of semi-natural dry and wet habitats were represented by 14%, i.e. a proportion comparable to pests, but with only 4% of individuals. The numbers of species and individuals recorded and the Shannon-Wiener diversity and evenness indices are lower than at natural sites. Yet, overall biodiversity is relatively high, including the presence of some rare, ecologically, or zoogeographically remarkable species.O
The Benefit of Mycorrhizal Fungi and Beneficial Soil Bacteria in Drought Exposed Lettuce (Lactuca sativa var. capitata) Is Genotype and Environment Dependent
Get PDFMorphological and biochemical responses were assessed in an iceberg (GIL) and butterhead (GBL) lettuce (Lactuca sativa var. capitata) treated with commercially available soluble preparation of mycorrhizal fungi and beneficial soil bacteria (MT) grown in three irrigation treatments considered in greenhouse (continental Croatia, 2022): I100-control treatment (100% volumetric water content-VWC); I80-80% VWC, moderate drought and I60-60% VWC, severe drought), in two growing cycles. MT was applied during lettuce drought-sensitive stages, i.e., transplanting and heading. Study results show that MT improved lettuce growth-related traits, yet the results are genotype and growing-cycle dependent. The beneficial effect of MT was also noted for root length, weight, and diameter which confirms the mycorrhizal role in improving the plant water uptake. Both lettuce genotypes responded to water deficit by overproduction of MDA and proline content, whereby the response of tested variables was growing cycle and genotype-specific. Both genotypes in severe drought treatment (MT-I60) responded with higher MDA in the first growing cycle and lower MDA content in the second growing cycle. MT-I60 treatment reduced proline accumulation in GBH in both growing cycles, while increased accumulation in GIL during the second growing cycle. The responses of lettuce to MT are genotype-specific and shaped by environmental conditions.O
What are the critical success factors for small farming businesses? Evidence from Zambia
Get PDFSmall farming businesses play a cardinal role in most countries, as they contribute to food security, employment creation, and rural development. However, small farming businesses face a number of challenges that have potential to hinder their performance. The purpose of the study is to identify critical success factors for small farming businesses in Zambia. The study employed an exploratory approach that involved multiple cases of six small farm owners. Additionally, four experts from the agriculture industry were also involved in the study. Semi-structured interviews were used to collect data, which was analyzed thematically using Atlas.ti software. Seven common dimensions emerged as critical success factors. These critical success factors include entrepreneurial characteristics, availability of financial resources, farm management practices, adoption of technology, knowledge, networking, and government support. The study provides implications that can help with development of the small farming businesses in Zambia.OA-hybri
Visitors' perspectives on sustainable tourism: a comparative study of national parks in Kosovo, Montenegro and Albania
No full textThis study investigated tourists' opinions on destination experiences within National Parks (NPs) in Kosovo, Montenegro and Albania, focusing on visitor satisfaction with the destination. Data was collected in the field through 366 surveys to assess visitor perspectives. The statistical analysis included descriptive, qualitative, and quantitative methods. The results highlight variations in visitor ratings across destinations, with Montenegro generally receiving higher (positive) ratings than Kosovo and Albania. The most valued issues by visitors are the diversity and wildness of the landscapes, food and hospitality. At the same time, the least valued (negative) are road infrastructure, orientation signs and waste management in the park. The study highlights the importance of visitor feedback in formulating sustainable tourism strategies, emphasising the need for balanced growth and environmental conservation in destination management.Published Versio
The Effect of Oil-based Polymer Coated CAN Fertilizer on the Yield and Quality of Triticum aestivum L. and Brassica napus L.
Get PDFThe fertilization with nitrogen plays a crucial role in today's agriculture characteristic with a high demand for production. The utilization of coated fertilizers represents a possible option to lower the number of applications, lower the dose and limit the risk of environmental losses. The effect of conventional calcium ammonium nitrate (CAN) applied in a single application in blend (1:1 or 1:2) with oil-based polymer coated CAN in thicknesses of 4 (cCAN4) or 6% (cCAN6) by weight of the fertilizer on the yield and quality of winter wheat and oilseed rape was evaluate. The average yields of winter wheat were not significantly influenced by the examined fertilization in either the growing season (GS) or the experimental site. On the contrary, the qualitative parameters on average resulted in lower values in comparison with the control (split N fertilization), possibly due to the single application of nitrogen in early spring. The examined treatments significantly influenced the seed yield of oilseed rape in both GS and both experimental sites. On average, the highest yield of seed (2.8 t/ha) was observed on treatment cCAN4 in a 1:2 ratio. This represents a significant increase by 24.8% compared to the control (2.2 t/ha). Similarly, to winter wheat, the qualitative parameter of oilseed rape (oil content) was lower after the examined blends with coated CAN. The fertilization of oilseed rape with blends of uncoated and coated CAN applied in the single application is a validate alternative to commonly used split nitrogen doses applied repeatedly during vegetation.OA-hybri
The generalized Kelvin chain-based model for an orthotropic viscoelastic material
Get PDFWe propose a constitutive material model to describe the rheological (viscoelastic) mechanical response of timber. The viscoelastic model is based on the generalized Kelvin chain applied to the orthotropic material and is compared to the simple approach given by standards. The contribution of this study consists of the algorithmization of the viscoelastic material model of the material applied to the orthotropic constitutive law and implementation into the FEM solver. In the next step, the fitting of the input parameters of the Kelvin chain is described, and at least a material model benchmark and comparison to the approach given by standards were done. The standardized approach is based on the reduction of the material rigidity at the end of the loading period using a creep coefficient, whereas the loading history state variables are not considered when establishing the result for a specific time step. The paper presents the benefits of the rheological model. It also demonstrates the fitting algorithm based on particle swarm optimization and the least squares method, which are essential for the use of the generalized Kelvin chain model. The material model based on the orthotropic generalized Kelvin chain was implemented into the FEM solver for the shell elements. This material model was validated on the presented benchmark tasks, and the influence of the time step size on the accuracy of model results was analyzed.OA-hybri
Elasto-plastic material model of green beech wood
Get PDFPhysically modelling the mechanical response of a tree by numerical simulation depends on having accurate data on the mechanical properties of green hardwood. Lacking such data, we developed and validated an orthotropic elasto-plastic (E-P) material model, based on the results of experiments performed on European beech (Fagus sylvatica L.) green wood, capable of including both the non-linearity and orthotropic properties of the material. We selected 655 clear samples with the special orthotropic structure of annual rings. All samples were prepared immediately after felling; their moisture content (MC) was 80% on average. The mechanical responses in normal directions and shear are represented by bi-linear stress-strain curves. The E-P model was validated by comparing the force-deflection response of three-point bending of green wood samples in a finite-element method (FEM) simulation (the average relative error was 4.6% for point-wise and 1.7% for integral-wise comparison). The output of this work was a consistent set of material constants for the E-P material model that is now available for the structural analysis of beech wood with MC above to fibre saturation point (FSP), especially green wood, subjected to relatively high loads (such that a plastic deformation appears) and that can very well predict a non-linear response above the proportional limits.O