Background and objectives: Melanocytic nevi are among the most common skin lesions, yet their relationship with the peripheral nervous system has remained understudied. Given the neural crest origin of melanocytes and Schwann cells, and the neurotrophic signaling capabilities of pigment cells, this study aimed to investigate the density of nerve fibers within nevi and assess how it varies with respect to histological subtype and anatomical location. Materials and Methods: A total of 90 nevi were analyzed, including junctional, compound, and intradermal types, distributed across the head, trunk, and limbs. Immunofluorescence staining for the pan-neuronal marker PGP 9.5 and for CGRP were performed and nerve fiber density was quantified. Statistical evaluation using two-way ANOVA revealed that both nevus type and anatomical site significantly influenced the degree of total innervation. Results: Junctional nevi demonstrated the highest total nerve fiber density, significantly exceeding that of compound and intradermal nevi. Likewise, nevi located on the head exhibited a significantly greater density of PGP 9.5-positive nerve fibers compared to those on the trunk and limbs. No significant correlation was observed between nevus type and location, suggesting that both factors contribute independently to the differences in innervation. CGRP-positive innervation was uniform regardless of the histological type of nevus and anatomical location. Conclusions: These findings likely reflect the facts that junctional nevi reside at the dermo-epidermal junction, where nerve fibers are most abundant, while the skin of the head and neck is well known to be more richly innervated than other regions. In contrast, analysis of CGRP-positive fibers suggests that the heterogeneity detected with PGP 9.5 is primarily driven by other neuronal populations. The results support the hypothesis of a dynamic relationship between nevi and the peripheral nervous system, potentially mediated by neurotrophic factors. Understanding this interaction may provide insight into nevus biology, sensory symptoms reported in some lesions, and the evolving role of nerves in the tumor microenvironment.
The genus Temnostoma comprises saproxylic hoverflies whose larvae develop by boring into wet, decaying wood, where they feed on microorganisms. Records of these species in the northwestern Balkans are sparse in the literature and nearly absent from openaccess databases. To enhance knowledge of their distribution in the region, we present new records of four Temnostoma species from Croatia, Bosnia and Herzegovina, and Serbia. Three species were recorded in all three countries, while T. apiforme was found exclusively in Croatia. This discovery marks not only the first record of this species in the country but also the first for the entire Balkan Peninsula. Furthermore, Temnostomameridionale was documented in Bosnia and Herzegovina for the first time. Given thatthese hoverflies are large and visually striking, we hope this study will inspire interestamong citizen scientists and encourage future contributions to the documentation ofthis genus in the region.
Alien species Trichopoda (Galactomyia) pictipennis Bigot, 1876 was found in southeasternBosnia and Herzegovina and Croatia in June and August 2024. This is the first recordof this species for Bosnia and Herzegovina and the southeastern part of Croatia.Additionally, this report includes the records from Montenegro and Bulgaria obtainedfrom the online data platform iNaturalist representing the first observations of T.pictipennis for Montenegro and the Black Sea coast in Bulgaria.
Although autism has historically been conceptualized as a condition that emerges in early childhood1,2, many autistic people are diagnosed later in life3, 4–5. It is unknown whether earlier- and later-diagnosed autism have different developmental trajectories and genetic profiles. Using longitudinal data from four independent birth cohorts, we demonstrate that two different socioemotional and behavioural trajectories are associated with age at diagnosis. In independent cohorts of autistic individuals, common genetic variants account for approximately 11% of the variance in age at autism diagnosis, similar to the contribution of individual sociodemographic and clinical factors, which typically explain less than 15% of this variance. We further demonstrate that the polygenic architecture of autism can be broken down into two modestly genetically correlated (rg = 0.38, s.e. = 0.07) autism polygenic factors. One of these factors is associated with earlier autism diagnosis and lower social and communication abilities in early childhood, but is only moderately genetically correlated with attention deficit–hyperactivity disorder (ADHD) and mental-health conditions. Conversely, the second factor is associated with later autism diagnosis and increased socioemotional and behavioural difficulties in adolescence, and has moderate to high positive genetic correlations with ADHD and mental-health conditions. These findings indicate that earlier- and later-diagnosed autism have different developmental trajectories and genetic profiles. Our findings have important implications for how we conceptualize autism and provide a model to explain some of the diversity found in autism. A study of several longitudinal birth cohorts and cross-sectional cohorts finds only moderate overlap in genetic variants between autism that is diagnosed earlier and that diagnosed later, so they may represent aetiologically different conditions.
The machinability of wood is an insufficiently researched problem that is mainly related to the machinability of metals. The machinability of a material is a technological property that expresses the ability to remove the maximum amount of crisps from the machined surface in the shortest possible time with satisfactory machining quality and the lowest possible cutting forces and tool wear. The quality and efficiency of the production process when milling solid wood is influenced by the following factors: type of wood, density and moisture content of the wood, temperatures and dimensions of the workpiece as well as the hardness and strength of the wood. The parameters of the milling mode, such as the main and auxiliary motion, the cutting force and power and the power of the drive unit, have a direct effect on the milling process and are related to the milling tool, i.e. the type and quality of the material from which it is made, the number of cutting edges, the geometry of the cutting edge and the sharpness of the tool. In this work, the influence of significant input parameters on the machinability of solid wood in flat peripheral milling is analysed as a function of the cutting force as an output parameter by planning an experiment. The experimental results are mathematically modelled with the aim of obtaining a mathematical model of the process of large-scale milling of solid wood, i.e. its parameters as a function of the cutting force. The results of the experimental part and the results of the models are analysed and compared in order to draw appropriate conclusions and
Considering that two-layer parquet is composed of two lamellas—most commonly 10 mm birch plywood and 4 mm solid oak—bonded together with adhesive, and that profiling is required to create a joint that serves a mechanical function, the process becomes complex and imposes significant demands on the cutting tool. This paper presents an experimental analysis of how the type of cutting tool affects the surface quality, profile stability, and edge wear of the tool after a certain machining length. Two different technological solutions were analyzed: a tool with replaceable tungsten carbide (TC) inserts and a tool with an integrated polycrystalline diamond (PCD) cutting edge. A particular focus of the analysis is the wear of the TC tool in the area of the oak and plywood joint profile, where selective wear of the TC edge occurs, potentially causing profile deformation and a weaker joint. The obtained results show that using PCD tools in two-layer parquet profiling achieves better surface finish, longer tool life, more consistent geometry of the cutting edge, and thus a more stable parquet profile.
Background: The European honey market is reported to be in a trou-bling state, far from being considered healthy. A comparison of honey with other food commodities has been conducted to identify specific characteristics of the conducing sector that may provide inspiration for measures to regulate hon y markets. Market indicators: Several general indicators used to describe markets for food production have been analysed to examine the current state of the honey market, offering insight into the primary market challenges or honey-anessential prerequisite developing strategies to address these identified challenges. Variations in market indicators between EU Member States are also presented. Policies related to market indicators: The overarching aim of the European Union, as defined by the Lisbon Treaty, is summarized, alongside a review of some relevant EU and national regulations related to apiculture. Policy me sures previously implemented to regulate certain aspects of other food commodity markets are evaluated for their feasibility in the hon y market. Results and conclusions: It is argued that regulatory me sures could potentially impro e the stability and security of income for beekeep-ers within the honey market. However, there is a risk, or possibly an opportunity, that such measures could drive production towards larger and more professional beekeepers, while smaller, amateur beekeepers may face economic and other difficulties in meeting the stricter regulatory requirements
In this paper, we will process the results of experimental and numerical analysis on the example of the boom of a machine tool - a rotary excavator. Rotary excavator SRs 1200/630 KW - 22/2, engine no. 1, field “D”, produced by “LAUHAMER” - German Democratic Republic, is intended for mining coal and tailings at the surface mine of the JP RB “KOLUBARA” Lazarevac mine. During the regular overhaul and after 35 years of operation of the rotary excavator, it was concluded that it would be necessary to assess the stress and deformation state of both the rotary excavator as a whole and its vital parts individually (primarily the excavator booms) through adequate tests. The goal is to determine the critical points on the arrow structure after the tests have been carried out and act preventively to avoid accidents and additional unnecessary costs. By comparing the experimental and numerical results, we obtained a representation of the stresses and strains on the shaft construction and defined the critical stresses and strains.
Mathematical modeling is a key tool in engineering as it enables the analysis and prediction of material behavior under specific conditions. This study focuses on material strength, which is one of the most critical aspects of engineering design and manufacturing. Understanding material strength is essential for ensuring the reliability and safety of structures and products. The structure of the paper includes a theoretical overview of the fundamentals of mathematical modeling and regression analysis, a detailed description of the experimental research, the development of a model based on collected data, and the evaluation of the obtained mathematical model. Testing was conducted using a tensile testing machine, with samples of standard dimensions in accordance with EN 10002.
The rise in the consumption of multimedia content has resulted in the demand to provide an exceptional user experience. However, modelling user-perceived Quality of Experience (QoE) presents a complex challenge. This fuels ongoing efforts to understand and measure QoE. To assess it, researchers rely on both subjective quality assessment (where users view and rate videos) and objective quality assessment (where quality metrics are designed to calculate perceived video quality). Although subjective evaluation is essential for mapping user experience to objective metrics, many studies omit the analysis of the impact of content preferences on user experience. This oversight limits our understanding of how video content influences QoE perception.To address this limitation, we created a multi-content video dataset with impairments based on realistic network conditions. Furthermore, we conducted a subjective study in a controlled environment evaluating the impact of user content category preferences and user video preference on QoE. One of our initial findings is that the actual video denoted as uninteresting by users had the most negative impact on the overall user QoE, but had no impact on user perception of other video degradations.
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