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Four new species of Collybiopsis (Omphalotaceae, Agaricales) from subtropical regions of China
No full textFour new species of Collybiopsis, namely C. subpolygramma, C. fucata, C. dentata, and C. latispora, were discovered in the subtropical regions of China. These species were identified based on morphological characteristics and molecular analysis. Morphologically, C. subpolygramma is characterized by its pileal surface, white in color with a light brown center; slender, cylindrical cheilocystidia; and absence of pleurocystidia. C. fucata is recognized by the reddish-brown, hygrophanous pileus; adnate to adnexed lamellae; and relatively broad basidiospores. C. dentata is identified by free lamellae, fusiform to utriform pleurocystidia, and relatively broad basidiospores. C. latispora is distinct by relatively broad basidiospores and a minute, snow-white ring or ruff at the stipe base. In the phylogenetic analysis based on combined ITS and LSU sequences, the four new species formed distinct and stable branches (BI-PP = 1; ML-BP = 100%), respectively. Collybiopsis subpolygramma formed a sister lineage with C. polygramma. The new species C. fucata, C. dentata, and C. latispora were found to be nested within the C. ramealis species complex clade. Detailed descriptions, color photos, and a key to related species are presented
The role of grooming in regulating biomass growth of ants and symbiotic fungi under entomopathogenic fungal infection: experiments and mathematical modelling
No full textThis study presents an extended mathematical model, originally developed to explore biomass dynamics in Acromyrmex ants and their symbiotic fungus, which has been adapted to investigate biomass growth in Atta sexdens and its fungal partner. The model incorporates ant grooming as a defence against entomopathogenic fungi, building on experimental data where self-grooming and allogrooming were quantified across three groups: Metarhizium anisopliae, Escovopsis phialicopiosa, and a control. A second chamber was introduced to simulate biomass transfer between compartments. Inflection points in growth curves were identified to detect shifts in population dynamics, and bifurcation diagrams explored key parameters affecting system stability, namely worker allocation to fungal cultivation, ant mortality, and fungal mortality. Metarhizium anisopliae significantly reduced both ant and fungal biomass, even under optimal grooming conditions, owing to its direct virulence to workers. In contrast, E. phialicopiosa, an opportunistic pathogen, had minimal impact unless fungal mortality exceeded a critical threshold. Self-grooming proved more effective than allogrooming in mitigating M. anisopliae effects, likely owing to prioritisation of individual defences under high pathogen pressure. Spatial dynamics enhanced resilience: one-way transfer between chambers redistributed biomass, delaying inflection points and bolstering structural stability. Bifurcation analysis revealed that extreme proportions of workers cultivating the symbiotic fungus reduced the biomass for both partners, whilst ant and fungal mortality rates led to non-linear declines in most simulations. These findings underscore the role of multi-chamber architecture in mitigating pathogen impacts in Atta colonies and suggest potential applications for biological control strategies by identifying behavioural and structural factors that may limit or enhance the effectiveness of pathogenic fungi in field settings. The model provides a useful framework for understanding epidemiological dynamics in natural nests, integrating behavioural defences and spatial strategies to safeguard this mutualism
IBASAM: a spatially explicit demo-genetic individual-based model for anadromous salmonids (meta)populations
No full textTo improve our understanding and management of species’ response to environmental and anthropogenic changes, there is a critical need for integrative modeling approaches that encompass demographic, ecological and evolutionary processes in a unified framework. This is especially crucial for anadromous salmonid fishes that hold significant socio-economic value. Mechanistic models, particularly Demo-Genetic Agent-Based Models (DG-ABMs), are promising tools to address this challenge. Building on previous work, we present IBASAM, an Individual Based Anadromous SAlmonids Model. It incorporates significant advancements, including new processes such as dispersal and in-river movement, enhanced flexibility for simulating diverse spatial configurations- from river dendritic networks to metapopulations and multiple marine areas- and the integration of variation in life history phenology and the genetic architecture of traits. Additionally, a user-friendly interface has been developed to facilitate broader application. This improved versatility enables IBASAM application to a number of populations and species of anadromous salmonids, making it well-suited for a wide range of ecological and evolutionary studies. The model is particularly suited for investigating (meta)population eco-evolutionary dynamics, persistence, and adaptation to environmental changes, as well as exploring management options including fisheries regulation and river connectivity restoration. We summarize the model’s structure and illustrate some of its novelties, parameterization, and emerging patterns with the case study of a naturally reproducing Atlantic salmon population simulated over 100 years, with constant fishing rates and no climatic trend. Our simulations successfully reproduced 30 variables observed over 30 years in the Scorff population. IBASAM opens up new opportunities for research on the response of salmonid meta-populations to environmental changes, the exploration of management practices, with further developments possible
Temporal and spatial herbarium density of Favratia zoysii (Wulfen) Feer (Campanulaceae): Insights into type material and historical distribution of an alpine endemic
No full textFavratia zoysii (Wulfen) Feer is a chasmophyte endemic to the south-eastern Alps and the sole representative of the genus Favratia Feer. Its primary occurrences are in Julian Alps and on Mt. Storžič (Kamnik-Savinja Alps) in Slovenia. This study aims at elucidating the original material utilised by Wulfen in the initial description of Campanula zoysii, later reclassified as F. zoysii by Feer, while also exploring the temporal and spatial density of the species’ herbarium collections. To this end, we examined preserved collections from six institutions, including botanical gardens and museums. A total of 127 herbarium vouchers were analysed to identify the specimens referenced by Wulfen. This comprehensive examination of historical collections, spanning over two centuries, allowed us to designate a lectotype, thereby providing a clear typification of F. zoysii. Additionally, we analysed the frequency and geographic distribution of herbarium specimens, a concept referred to as temporal and spatial herbarium density. This combined typification and spatial-temporal analysis not only strengthens the taxonomic clarity of the species, but also provides valuable insights into its botanical history, distribution patterns and conservation needs
Checklist of coastal fishes from Cabo Verde Archipelago
No full textTaxonomic and geographic misattributions in biodiversity inventories remain a pressing issue in biogeographical research, particularly in regions with overlapping or similar place names. The Republic of Cabo Verde (also known as Cabo Verde Islands) and the Cape Verde Peninsula (Senegal) exemplify this challenge, where historical and recent studies have struggled to provide accurate species distributions due to unverified, erroneous and ambiguous records. This underscores the necessity of comprehensive, reliable datasets to delineate species occurrences across these distinct geographic areas.This study provides a rigorously verified inventory of coastal fish species occurring within the Exclusive Economic Zone (EEZ) of the Republic of Cabo Verde, focusing on depths between 0 and 200 metres. By delineating the faunal composition specific to Cabo Verde, this work addresses the recurrent confusion with species lists referencing the Cape Verde Peninsula (Senegal).A total of 393 species, distributed among 125 families and 40 orders, is documented, offering an invaluable resource for refining biodiversity assessments and providing information forconservation strategies in this biogeographically unique region. Two species, Thalassoma newtoni (Osório, 1891) and Diodon eydouxii Brisout de Barneville, 1846, are reported for the first time from Cabo Verde in this paper
DNA barcoding and species delimitation of crickets, katydids, and grasshoppers (Orthoptera) from Central and Southern Europe, with focus on the Mediterranean Basin
No full textThe Mediterranean Basin, recognized as a global biodiversity hotspot, harbors a remarkable diversity of grasshoppers, katydids, and crickets, many of which are endemic and potentially contain cryptic lineages. In this study, we generated a comprehensive dataset comprising 1,441 barcodes from 270 identified species within the Ensifera and Caelifera suborders. These were combined with existing data to form a dataset of 2,606 barcodes representing 351 species. We employed Maximum Likelihood (ML) topology reconstruction and applied five species delimitation methods (BIN, ABGD, ASAP, GMYC, and PTP) to detect potential incongruences between Operational Taxonomic Units (OTUs) and existing taxonomic classifications. Our analysis revealed that OTUs delimited by these methods corresponded to 71.39% of the evaluated species, with a notably higher congruence in Ensifera (88.53%) compared to Caelifera (52.15%). Across the dataset, we identified 54 lineages comprising cryptic species, indicating significant unrecognized diversity within these groups. Additionally, 21 instances of species being merged into consensus OTUs were observed, suggesting either the need for taxonomic revision or highlighting the limitations of current genetic markers. Among the methods tested, ABGD, particularly with the Kimura two-parameter model, was the most consistent with traditional taxonomy, yielding the highest consensus rates. In contrast, the PTP method exhibited the lowest consensus, often leading to an oversplitting of lineages. These findings underscore the complexity of species delimitation in recently radiated taxa and emphasize the importance of using multiple methodologies to accurately capture biodiversity, especially in regions characterized by a high prevalence of cryptic species
CYP1A1 and GSTM1 genes associated with the risk of developing colorectal cancer: a case-control study in the Lima region of Peru
No full textThe presence of CYP1A1 allelic variants and deletion of the glutathione S-transferase GSTM1 gene, and their imbalance, have been suggested as risk factors for inducing colorectal cancer (CRCa). The objective was to identify CYP1A1 and GSTM1 and evaluate the association with the risk of developing colorectal cancer in a sample of cases and controls from Lima, Peru. This was a case-control study of CYP1A1 and GSTM1 genes in 50 samples from patients diagnosed with colorectal cancer and 50 samples from controls without cancer, using the PCR-based restriction fragment length polymorphism method. A significant risk of developing CRCa was found in the following groups: GSTM1*0 carriers with no history of smoking or family history of cancer (OR = 3.56, 95% CI 1.43–8.88, p = 0.0060); GSTM1*0 with family history of cancer without smoking (OR = 2.81, 95% CI 0.35–22.49, p = 0.3280); GSTM1*0 exacerbated by smoking (OR = 1.41, 95% CI 0.11–17.11, p = 0.7880); CYP1A1*2A/*2A carriers with family history and smoking (OR = 1.50, 95% CI 0.13–16.54, p = 0.7410). An association of wild genotypes exacerbated by non-genetic factors with risk of developing CRCa was also found: CYP1A1*1A/*1A with family history of cancer but no history of smoking (OR = 2.94, 95% CI 0.11–35.80, p = 0.6380); GSTM1 (+) with history of smoking but no family history of cancer (OR = 5.63, 95% CI 0.46–68.46, p = 0.1750); GSTM1 (+) associated with family history and smoking (OR = 9.86, 95% CI 1.77–54.89, p = 0.0090). According to univariate statistical analysis, carriers of CYP1A1*2A and GSTM1*0 without association with family history of cancer and smoking would not be related to the risk of CRCa. An association was established between GSTM1*0 and CYPA1*2A/*2A with colorectal cancer exacerbated by family history and smoking. The risk is higher with wild-type genotypes of CYP1A1*1A/*1A and GSTM1 (+) induced by family history and smoking, respectively
A long-term monitoring of micro-tectonic movements in caves at Cape Kaliakra, Northeast Bulgaria: Correlation with seismic events and precipitation
No full textThis article aims to present the results of an 11-year monitoring of micro-tectonic movements along dangerous cracks opening in caves at Cape Kaliakra, Northeast Bulgaria. Two 3D monitoring devices TM71, were installed in two caves, the purpose of which is to monitor the movements of the rock blocks along dangerous cracks. The obtained results of microdisplacement measurements from 2013 to 2023 show active movement along the observed cracks. This is expressed not only in linear trends but also in sudden shifts and short-term shifts followed by recovery (oscillations). The comparison with the local and regional seismicity shows a correlation between the abrupt movements and seismic events along the Batovo fault. Data from the automatic weather station in the town of Kavarna point to a possible link between some oscillation type movements and heavy rainfall in the research area. The results of the analyzes show the importance of long-term monitoring in clarifying the recent geodynamics in the research area. The results obtained provide valuable information about the dynamics of this region, and hence about the geomorphological evolution and the physical-geological hazardous phenomena. The registered movements show the connection between gravitational movements and tectonic ones. For the first time, data obtained through instrumental observations are published, proving the activity of fault structures in this part of Bulgaria. The results can also be used to predict dangerous slope destabilizations, as well as to reduce the risk of their occurrence
Boron-containing radiator coatings of ionization chambers of neutron flux detection sensors
No full textThe proposed solution for the production of new boron-containing radiator materials – composite coatings with neutron conversion material (10B isotope) – for ionization chambers electrodes is based on the technology of chemical and structural modification of the surface using heat-resistant oxide materials (silicon and boron oxides). The paper presents the results of the development of a neutron-sensitive radiator material based on an oxide micro-dimensional composite coating consisting of an intermediate adhesive layer of silicon dioxide (SiO2) and a neutron-sensitive functional layer of boric anhydride (B2O3). The technological basis consists of the sequential processes of thermal destruction of polyorganosiloxane of the PES-5 brand and pyrolytic decomposition of boric acid (H3BO3). Studies using infrared and fiber-optic interferometric spectroscopy have shown that during the formation of a silicon dioxide layer, an amorphous silicate of a linear chain structure with a developed surface is formed, which contributes to the subsequent formation of a functional boric anhydride layer. The specific neutron sensitivity of boron-containing radiator coatings was measured by alpha spectrometry. It was found that at a surface density of boric anhydride of 2.5 mg/cm2, the specific neutron sensitivity is of the order of 3∙10-18Coulomb/neutron. It is shown that the boron-containing radiator coating retains its integrity and nuclear physical properties during thermocyclic tests (4 cycles at 600 °C). The boron-containing radiator coating is characterized by high adhesion properties to the metallic surface of the electrodes (grade 321 steel) of the ionization chamber. The composite coating is resistant to vibration when exposed to high-frequency (200 Hz) and low-frequency (6–35 Hz) vibration loads
To study the burden of post tubercular obstructive airway diseases in patients visiting chest OPD at a tertiary level chest OPD in North India: a descriptive cross-sectional study
No full textAbstract COPD and tuberculosis are on the rise in developing countries. There is evidence of post-tuberculosis lung function deterioration and the occurrence of obstructive airway diseases in such patient groups.Objectives: To study the burden and severity of obstructive airway disease in subjects with a history of pulmonary tuberculosis and find the demographic trends, features, and clinical presentations in tuberculosis-associated obstructive pulmonary disease (TOPD) and non-tubercular obstructive airway disease (non-tubercular OAD).Methodology: We investigated 125 patients divided into two groups, i.e., post-tubercular airway disease (n = 50) and airway disease due to other aetiology (n = 75). Age, gender, and BMI were analysed. Dyspnea grade was analysed using the Modified Medical Research Council (m MRC) scale. Spirometry was performed to find the pattern of airway disease in both groups. The severity of obstruction and lung functions were analysed using GOLD guidelines and spirometry.Results: The males accounted for 71.2%, and females –28.8% of the patients. There were more females in the tubercular airway disease group. The mean age of the tubercular group (46.94 ± 14.67) was significantly lower than that of the non-tubercular airway disease (58.47 ± 6.14). No significant difference was found for BMI. Obstructive airway disease was more common in both groups (46% and 49.30%, respectively), and the severity of obstruction was higher in the TOPD group. The severity of cough and dyspnea was higher in that group. FVC and FEV1 were significantly reduced in TOPD compared to non-tubercular obstructive airway disease (non-tubercular OAD). The mean latency of COPD symptoms after completion of ATT was found to be 5.38 ± 6.77 years.Conclusion: Post-tuberculosis subjects presented with lung function decline without confounding factors like smoking; thus, early screening of COPD is required once diagnosed; appropriate treatment should be initiated as early detection and treatment of these patients can help in better disease management and optimum treatment outcomes