Search Results (343)

Accurately estimating the radiation dose received by an individual is essential for evaluating potential damage caused by exposure to ionizing radiation. Most retrospective dosimetry methods require the time since exposure to be known and rely on calibration curves specific to that time point. In this work, we introduce a novel method tailored to the γ-H2AX assay, which is a protein-based biomarker for radiation exposure, that enables the estimation of both the radiation dose and the time of exposure within a plausible post-exposure interval. Specifically, we extend calibration curves available at two distinct time points by incorporating the biological decay of foci, resulting in a model that captures the joint dependence of foci count on both dose and time. We demonstrate the applicability of this approach using both real-world and simulated data. Full article

The availability of detritus is a key factor influencing aquatic biota and can significantly affect decomposition processes. In this study, we investigated how varying quantities of surrounding detritus impact leaf litter decay rates. It was tested in flowing and still-water microcosms to highlight context-dependent effects of surrounding detritus on leaf litter decomposition. To isolate the effect of detritus amount, experiments were conducted in laboratory microcosms simulating lotic and lentic ecosystems, each containing leaf fragments for decomposition assessments. Four detritus quantities were tested, with invertebrates either allowed or restricted from moving among detritus patches. Leaf decomposition rates were influenced by the amount of surrounding detritus, with slower decay observed at higher detritus conditions, regardless of invertebrate mobility. Detritivore distribution responded to both detritus quantity and oxygen availability, showing a preference for high detritus conditions. Additionally, detritus quantity affected microbial activity with a quadratic response, as indicated by leaf respiration rates. Overall, our findings indicate that the amount of surrounding detritus modulates leaf litter decomposition independently of invertebrate density, by influencing oxygen dynamics and, consequently, the activity of biological decomposers. Full article

Sin Nombre virus (SNV) is the main causative agent of hantavirus cardiopulmonary syndrome (HCPS) in North America. SNV is transmitted via environmental biological aerosols (bioaerosols) produced by infected deer mice (Peromyscus maniculatus). It is similar to other viruses that have environmental transmission routes rather than a person-to-person transmission route, such as avian influenza (e.g., H5N1) and Lassa fever. Despite the lack of person-to-person transmission, these viruses cause a significant public health and economic burden. However, due to the lack of targeted pharmaceutical preventatives and therapeutics, the recommended approach to prevent SNV infections is to avoid locations that have a combination of low foot traffic, receive minimal natural sunlight, and where P. maniculatus may be found nesting. Consequently, gaining insight into the SNV bioaerosol decay profile is fundamental to the prevention of SNV infections. The Biological Aerosol Reaction Chamber (Bio-ARC) is a flow-through system designed to rapidly expose bioaerosols to environmental conditions (ozone, simulated solar radiation (SSR), humidity, and other gas phase species at stable temperatures) and determine the sensitivity of those particles to simulated ambient conditions. Using this system, we examined the bioaerosol stability of SNV. The virus was found to be susceptible to both simulated solar radiation and ozone under the tested conditions. Comparisons of decay between the virus aerosolized in residual media and in a mouse bedding matrix showed similar results. This study indicates that SNV aerosol particles are susceptible to inactivation by solar radiation and ozone, both of which could be implemented as effective control measures to prevent disease in locations where SNV is endemic. Full article

Spores of filamentous fungi are common biological particles in indoor air that can negatively impact human health, particularly among immunocompromised individuals and patients with chronic respiratory conditions. Airborne viruses represent an equally pervasive threat, with some carrying the potential for pandemic spread, affecting both healthy individuals and the immunosuppressed alike. This study investigated the abundance and diversity of airborne fungal spores in both hospital and residential environments, using custom designed air samplers with or without the presence of negative air ions (NAIs) inside the sampler. The main purpose of investigation was the assessment of biological effects of NAIs on fungal spore viability, deposition, mycelial growth, and sporulation, as well as airborne viral load. The precise assessment of mentioned biological effects is otherwise difficult to carry out due to low concentrations of studied specimens; therefore, specially devised and designed, ion-bioaerosol interaction air samplers were used for prolonged collection of specimens of interest. The total fungal spore concentrations were quantified, and fungal isolates were identified using cultural and microscopic methods, complemented by MALDI-TOF mass spectrometry. Results indicated no significant difference in overall spore concentration between environments or treatments; however, presence of NAIs induced a delay in the sporulation process of Cladosporium herbarum, Aspergillus flavus, and Aspergillus niger within 72 h. These effects of NAIs are for the first time demonstrated in this work; most likely, they are mediated by oxidative stress mechanisms. A parallel experiment demonstrated a substantially reduced concentration of aerosolized equine herpesvirus 1 (EHV-1) DNA within 10–30 min of exposure to NAIs, with more than 98% genomic load reduction beyond natural decay. These new results on the NAIs interaction with a virus, as well as new findings regarding the fungal sporulation, resulted in part from a novel interaction setup designed for experiments with the bioaerosols. Our findings highlight the potential of NAIs as a possible approach for controlling fungal sporulation and reducing airborne viral particle quantities in indoor environments. Full article

The marine habitats of the world’s oceans are being driven beyond their resilience. The ongoing biodiversity crisis is happening fast, within the lifespan of researchers trying to produce the information necessary for the conservation of habitats and marine ecosystems. Here, we report on the destruction of sciaphilic sessile communities and coralligenous concretions produced by the anchoring of a high-tonnage vessel inside a Marine Protected Area in Cyprus. The damage from the anchors and the chains consisted of the dislodgement of large boulders that were dragged or rolled over the seafloor, increasing the breakage and further dislodgement of more boulders; many were left upside-down. The biological communities that thrived in the dark environments below the boulders were directly exposed to high irradiance levels and went through a slow mortality and decaying process, most probably due to a combination of several deterioration agents, such as exposure to direct sunlight, predation, mucilage aggregates, and cyanobacterial blooms. The enforcement of regulatory measures for anchoring and transit in the MPA is necessary to prevent similar destruction. Given the extent of the irreversible damage to these sciaphilic communities, our study is, unfortunately, another environmental post-mortem contribution. Full article

The thermal modification of wood has emerged as a sustainable and effective method for enhancing the physical, chemical, and mechanical properties of wood without the use of harmful chemicals. This review summarizes the current state-of-the-art in thermal wood modification, focusing on the mechanisms of wood degradation during treatment and the resulting changes in the properties of the material. The benefits of thermal modification of wood include improved dimensional stability, increased resistance to biological decay, and improved durability, while potential risks such as reduced mechanical strength, color change, and higher costs of wood under certain conditions are also discussed. The review highlights recent advances in process optimization and evaluates the trade-offs between improved performance and possible structural drawbacks. Finally, future perspectives are outlined for sustainable applications of thermally modified wood in various industries. Emerging trends and future research directions in the field are identified, aiming to improve the performance and sustainability of thermally modified wood products in construction, furniture, and other industries. Full article

In this study, the dominant pathogenic fungus of gray spot disease in loquat, which was isolated from postharvest decaying loquat fruits in Zhenjiang, was identified as Pestalotiopsis vismiae (P. vismiae) by morphological characteristics and DNA sequencing. At the same time, a strain of yeast E1, which could effectively inhibit the pathogen, was isolated from the loquat leaves and soil and identified as Metschnikowia pulcherrima (M. pulcherrima) by morphological and molecular biological characteristics. It significantly reduced the natural decay of loquat fruits without affecting fruit quality. Metschnikowia pulcherrima E1 (M. pulcherrima E1) exhibited significant biocontrol efficacy against P. vismiae, the causal agent of gray spot in loquat, reducing disease incidence to 22.73% compared to 100% in the control group. Transcriptome analysis revealed 1444 differentially expressed genes (DEGs) (1111 upregulated, 333 downregulated), with key genes (CML19, XTH23, GSTU10) validated by RT-qPCR. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis highlighted enrichment in plant–pathogen interactions, glutathione metabolism, and phenylpropanoid biosynthesis. These findings provided molecular insights into yeast-induced resistance, bridging biocontrol applications with mechanistic studies. Full article

As one of the decay-resistant woods, Korean pine is widely used in the construction industry. However, even the most corrosion-resistant wood is still susceptible to decay under the right humidity and temperature conditions. In this study, Bacillus amyloliquefaciens (B. amyloliquefaciens) bacterial liquid and filter bacterial solution were prepared for the anti-corrosion treatment of Korean pine wood, aiming to improve its decay-resistant property. Through the plate confrontation test, it was discovered that B. amyloliquefaciens AW3 could significantly inhibit the growth of Fomitopsis pinicola (F. Pinicola). The results of mass loss rate, mechanical properties test, XRD, FTIR and SEM analysis showed that the preserved Korean pine wood had significant improvement in various properties compared with the decayed wood, which was manifested in the significant reduction of mass loss, improvement of mechanical properties, and increased wood cellulose diffraction peak intensity. There is no mycelium infection of F. pinicola in Korean pine wood, and the antiseptic liquid can penetrate into the wood evenly, which plays an effective antiseptic role. The B. amyloliquefaciens bacterial liquid exhibited superior preservative performance compared to the B. amyloliquefaciens filter bacterial solution. In conclusion, B. amyloliquefaciens, as an efficient and environmentally friendly biological preservative, holds broad application prospects in improving the anti-corrosion performance of Korean pine wood. Full article

Epidemics spread through shipping networks and have dual characteristics as both biological sources of infection and triggers of cascading failures. However, existing resilience models fail to capture this dual and coupled dynamics. To minimize the cascading impacts of epidemics on global shipping networks, this paper proposes an innovative resilience assessment framework that considers the interaction between epidemic transmission and the shipping network cascading failure. First, a weighted shipping network topology is constructed based on route flow characteristics to quantify route frequency, stopping time, and the number of infected people, and the epidemic transmission across ports is modeled with an improved SEIR model, which contains a heterogeneous infectivity function and a dynamic transmission matrix, revealing a dual transmission mechanism inside and outside the ports. Second, a two-stage cascading failure model is developed: a direct failure triggered by infected people exceeding the threshold and an indirect failure triggered by the dynamic redistribution of loads. The load redistribution strategy is optimized to reconcile the residual port capacity and the risk of infection. Finally, a multidimensional resilience assessment framework covering structural destruction resistance, network efficiency, path redundancy, and a cascading failure propagation rate is constructed. Example validation shows that the improved load redistribution strategy reduces the maximum connected subgraph decay rate by 68.2%, reduces the cascading failure rate by 88%, and improves the peak network efficiency by 128.2%. In case of multi-source epidemics, the state of the network collapse can be shortened by 12 days if the following recovery strategy is adopted: initially repair high connectivity hubs (e.g., Port of Shanghai), and then repair high centrality nodes (e.g., Antwerp Port) to achieve a balance between recovery efficiency and network functionality. The research results reduce the risk of systemic disruptions in maritime networks and provide decision-making tools for dynamic port scheduling during pandemics. Full article

Microalgae-based wastewater treatment systems are an environmentally friendly technology for reuse of polluted water produced in livestock farming. Since pollution removal depends on light availability, the performance should be evaluated under different seasonal conditions, even in reduced lab scale systems. This study evaluates the treatment of livestock digestate in an experimental High-Rate Algae Pond (HRAP) that recreates outdoor conditions. Chemical and biological pollution removal were analyzed, as well as the response of photosynthetic activity of the culture. Pollutant removal varied between seasons, while summer was characterized by higher nitrogen and phosphorus removal (81 and 69%, respectively), on the other hand, winter presented higher elimination of organic matter (91%) and pathogens. In this sense, P. aeruginosa removal was notably higher in winter (100%) than in summer (50%). Higher light penetration and increased photosynthetic efficiency in winter, along with greater fluctuations in pH and dissolved oxygen concentrations, contributed to higher levels of pathogen decay. Photosynthetic response tests indicated higher oxygen production per unit biomass in winter, suggesting physiological adaptations to lesser light conditions. This adaptation was correlated with the relative high pH and dissolved oxygen values registered. The findings highlight the adaptation and robustness of algae cultures as a solution for wastewater treatment and reuse in the primary sector. Full article

Rare earth elements (Ln: Sm, Eu, Tb, Dy) were complexed with caffeic acid (Caf), a natural phenolic compound, to synthesize novel luminescent complexes with enhanced biological activities. The complexes, formulated as Ln(Caf)₃·4H₂O, were characterized using infrared spectroscopy (IR), thermogravimetric analysis (TGA/DTA), mass spectrometry (MS), and fluorescence spectroscopy. Structural studies confirmed the coordination of caffeic acid via carboxylate and hydroxyl groups, forming stable hexacoordinate complexes. Luminescence analysis revealed intense emission bands in the visible spectrum (480–700 nm), attributed to f-f transitions of Ln³⁺ ions, with decay lifetimes ranging from 0.054 to 0.064 ms. Biological assays demonstrated significant antibacterial activity against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa, with inhibition zones up to 44 mm at 200 µg/mL. The complexes also exhibited potent anticancer activity against MCF7 breast cancer cells, with Sm(Caf)₃·4H₃O showing the lowest IC₅₀ value (15.5 µM). This study highlights the dual functionality of rare earth metal-caffeic acid complexes as promising candidates for biomedical imaging and therapeutic applications. Full article

Plastic pollution has become a critical environmental issue, with vast amounts of plastic waste accumulating in aquatic and terrestrial ecosystems. Plastic pollution poses significant risks to biodiversity by introducing toxic chemicals and disrupting biological functions. The drone fly, Eristalis tenax, is perhaps the most globally widespread hoverfly. This success is aided by its development as a rat-tailed maggot in a wide array of aquatic environments where it feeds on decaying organic matter. As an adult, E. tenax is a vital pollinator, visiting a wide range of crops and wild plants, and has been shown to vector pollen over hundreds of kilometres during seasonal migrations. Exposure to microplastics during larval stages has the potential to alter the provision of these ecosystem services and to provide a route for the long-distance vectoring of microplastics. To investigate this, we rear E. tenax in water contaminated with different concentrations of microplastic particles. We show that these plastics are retained in the gut from larval through to pupal to adult developmental stages. This contamination resulted in reductions of 33% and 60% in pupal and adult weight when exposed to the highest concentrations of microplastic particles but resulted in no detectable effects on mortality or developmental length. Our results demonstrate the potential for the vectoring of microplastics by this highly mobile species. However, the associated reductions in body size likely have profound consequences for movement capability in terms of foraging and migration and should be further investigated for their impact on ecosystem service provision. Full article

Background: Research in dental science reveals a need for enhanced oral healthcare among elite athletes due to the stress generated by excessive exercise. Consideration of the inherent biological distinctions between men and women is crucial in sports dentistry. Objectives: Thus, this study aims to analyse the differences in oral health status among elite athletes based on gender. A total of 186 elite athletes (150 men and 36 women) recognised in the region of Aragon (Spain) participated in this study (mean age 24.99 ± 9.34), all of whom practise individual sports. Methods: Oral health status analysis included: periodontal, malocclusion and tooth status measured using the restoration index (RI) and the decayed, missing and filled teeth (DMFT) index. Results: Women had fewer teeth, a lower restoration index (p < 0.05) and lower DMFT index values (p < 0.001); furthermore, this group showed a greater number of missing teeth (p < 0.001) and decayed teeth (p < 0.05). There were no statistical differences in malocclusion, plaque, gingival bleeding, dental erosion or bruxism values between the genders. Mouthguard usage was low (men = 9.4% vs. women = 14.3%; p = 0.57). Conclusions: This study highlights the need for a multidisciplinary approach to address the high prevalence of oral health issues among elite athletes, despite the differences in health status between men and women. Full article

Photoacoustic tomography (PAT), also known as optoacoustic tomography, has been emerging as a biomedical imaging modality that can provide cross-sectional or three-dimensional (3D) visualization of biological tissues such as blood vessels and lymphatic vessels in vivo at high resolution. The principle behind the visualization involves the light being absorbed by the tissues which results in the generation of ultrasound. Depending on the strength of ultrasound and its decay rate, it could be used to visualize the absorber location. In general, pulsed lasers such as the Q-switched Nd-YAG and OPO lasers that provide high-energy widths in the range of a few nanoseconds operating at low repetition rates are commonly used as a light source in photoacoustic imaging. However, such lasers are expensive and occupy ample space. Therefore, PAT systems that use LED as the source instead of lasers, which have the advantage of being obtainable at low cost and portable, are gaining attention. However, LED light sources have significantly low energy, and the photoacoustic signals generated have a low signal-to-noise ratio (SNR). Therefore, in LED-based systems, one way to strengthen the signal and improve the SNR is to significantly increase the repetition rate of LED pulses and use signal processing, which can be achieved using a high-power LED along M-sequence signal decoding. M-sequence signal decoding is effective, especially under high repetition rates, thus improving the SNR. However, power supplies for high-power LEDs have a circuit jitter, resulting in random temporal fluctuations in the emitted light. Such jitters, in turn, would affect the M-sequence-based signal decoding. Therefore, we propose a new decoding algorithm which compensates for LED jitter in the M-sequence signal processing. We show that the proposed new signal processing method can significantly improve the SNR of the photoacoustic signals. Full article

Genetic studies and phenotypic expansion of hearing loss (HL) for people living in Africa are greatly needed. We evaluated the clinical phenotypes of three affected siblings presenting non-syndromic (NS) HL and five unaffected members of a consanguineous Ghanaian family. Analysis of exome sequence data was performed for all affected and one unaffected family members. In-depth genetic and cellular characterization studies were performed to investigate biological significance of the implicated variant using bioinformatic tools and cell-based experimentation. Audiological examinations showed severe-to-profound, bilateral, symmetrical, and post-lingual onset. The whole-exome sequencing (WES) identified a homozygous frameshift variant: MARVEL domain containing 2 (MARVELD2):c.1058dup;p.(Val354Serfs*5) in all affected siblings. This frameshift variant leads to an early stop codon insertion and predicted to be targeted by nonsense medicated decay (mutant protein predicted to lack conserved C-terminal domain if translated). Cell immunofluorescence and immunocytochemistry studies exposed the functional impact of the mutant protein’s expression, stability, localization, protein–protein binding, barrier function, and actin cytoskeleton architecture. The identified variant segregates with NSHL in the index Ghanaian family. The data support this nonsense variant as pathogenic, likely to impact the homeostasis of ions, solutes, and other molecules, compromising membrane barrier and signaling in the inner ear spaces. Full article