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1.
Animals (Basel) ; 14(10)2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38791675

RESUMEN

Bovine respiratory disease complex, a complex respiratory ailment in cattle, results from a combination of viral and bacterial factors, compounded by environmental stressors such as overcrowding, transportation, and adverse weather conditions. Its impact extends beyond mere health concerns, posing significant economic threats to the cattle industry. This study presents an extensive investigation into viral pathogens associated with BRDC in Serbian cattle, utilizing serum samples and nasal swabs. A cross-sectional study was conducted in 2024 across 65 randomly selected dairy farms in Serbia, excluding farms with vaccinated cattle. The farms were categorized by their livestock count: small (≤50 animals), medium (51-200 animals), and large (>200 animals). Serum samples from adult cattle older than 24 months were tested for antibodies against BVDV, BHV-1, BRSV, and BPIV3. Nasal swab samples from the animals with respiratory signs were tested using PCR for viral genome detection. The results showed seropositivity for all four viruses across all of the farms, with BPIV3 exhibiting universal seropositivity. Medium-sized and large farms demonstrated higher levels of seropositivity for BRSV and BHV-1 compared to small farms (p < 0.05). Our true seroprevalence estimates at the animal level were 84.29% for BRSV, 54.08% for BVDV, 90.61% for BHV-1, and 84.59% for BPIV3. A PCR analysis of the nasal swabs revealed positive detections for BRSV (20%), BHV-1 (1.7%), BVDV (8%), and BPIV3 (10.9%). Influenza D virus was not found in any of the samples. This study provides critical insights into the prevalence and circulation of viral pathogens associated with BRDC in Serbian cattle, emphasizing the importance of surveillance and control measures to mitigate the impact of respiratory diseases in cattle populations.

2.
Environ Res ; 235: 116679, 2023 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-37454795

RESUMEN

Gully erosion leads to the formation of deep and wide channels that increase the risk of soil loss, flooding, and water pollution. In addition, this process reduces the productivity and viability of agricultural land and natural ecosystems. Preventing gully erosion is critical for maintaining ecological balance and preserving natural resources in certain areas. This paper presents a methodology integrating remote sensing and nuclear techniques to study gully erosion. The morphometric characterization of gullies using 360-degree camera photogrammetry was introduced as a new method in erosion research. This approach aims to investigate the suitability of unmanned aerial vehicle and terrestrial photogrammetry for modeling gullies, to study the variability of erosion processes in gullies at a small scale, and to compare the differences in erosion intensity between nearby gullies. The study's objectives include identifying the effective and economical method for gullies monitoring and providing a starting point for controlling and safeguarding gullies. Mainly erosion process was detected in the studied gullies, while deposition was identified at only 2 out of 39 sampling locations. The results showed an average soil redistribution rate of 16.2 t ha-1 yr-1 and coefficients of variation of 32%, 59%, and 91% for three investigated gullies. It was determined that aerial photogrammetry methods were not practical under the conditions prevailing in the study area. Highly detailed 3D models of the gullies were created using 360-degree photogrammetry. It was confirmed that the micro-relief obtained by photogrammetric modeling is an essential contribution to erosion research. The 360-degree camera photogrammetry serves as a reliable tool for analyzing the morphology of gullies and, in perspective, tracking changes in gully systems over time or monitoring the effectiveness of the applied protection measures.


Asunto(s)
Ecosistema , Tecnología de Sensores Remotos , Sistemas de Información Geográfica , Conservación de los Recursos Naturales/métodos , Ríos , Serbia , Suelo
3.
Adv Mater ; 35(18): e2211274, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36739507

RESUMEN

An approach to achieving dynamic and reversible decoration of DNA-based scaffolds is demonstrated here. To do this, rationally engineered DNA tiles containing enzyme-responsive strands covalently conjugated to different molecular labels are employed. These strands are designed to be recognized and degraded by specific enzymes (i.e., Ribonuclease H, RNase H, or Uracil DNA Glycosylase, UDG) inducing their spontaneous de-hybridization from the assembled tile and replacement by a new strand conjugated to a different label. Multiple enzyme-responsive strands that specifically respond to different enzymes allow for dynamic, orthogonal, and reversible decoration of the DNA structures. As a proof-of-principle of the strategy, the possibility to orthogonally control the distribution of different labels (i.e., fluorophores and small molecules) on the same scaffold without crosstalk is demonstrated. By doing so, DNA scaffolds that display different antibody recognition patterns are obtained. The approach offers the possibility to control the decoration of higher-order supramolecular assemblies (including origami) with several functional moieties to achieve functional biomaterials with improved adaptability, precision, and sensing capabilities.


Asunto(s)
ADN , Nanoestructuras , ADN/química , Conformación de Ácido Nucleico , ADN Glicosilasas/química
4.
Nat Nanotechnol ; 18(3): 290-298, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36646828

RESUMEN

Respiratory infections are the major cause of death from infectious disease worldwide. Multiplexed diagnostic approaches are essential as many respiratory viruses have indistinguishable symptoms. We created self-assembled DNA nanobait that can simultaneously identify multiple short RNA targets. The nanobait approach relies on specific target selection via toehold-mediated strand displacement and rapid readout via nanopore sensing. Here we show that this platform can concurrently identify several common respiratory viruses, detecting a panel of short targets of viral nucleic acids from multiple viruses. Our nanobait can be easily reprogrammed to discriminate viral variants with single-nucleotide resolution, as we demonstrated for several key SARS-CoV-2 variants. Last, we show that the nanobait discriminates between samples extracted from oropharyngeal swabs from negative- and positive-SARS-CoV-2 patients without preamplification. Our system allows for the multiplexed identification of native RNA molecules, providing a new scalable approach for the diagnostics of multiple respiratory viruses in a single assay.


Asunto(s)
COVID-19 , Virus , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , ARN Viral/genética , ADN/genética
5.
Chem Biodivers ; 19(12): e202200365, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36315629

RESUMEN

Four Artemisia species from Serbia were selected for the study: A. annua L., A. absinthium L., A. vulgaris L. and A. scoparia Waldst. et Kit. because of the proven excellent action in treating certain medical conditions and diseases. A. absinthium L., A. vulgaris L., A. annua L. and A. scoparia Waldst. et Kit. collected from different habitats across Serbia (48 samples in total) were studied from the statistical aspect considering the phenolic and flavonoid contents, compositions, and antioxidant activities of methanol extracts in correlation with the soil type. The components were identified using HPLC (High Performance Liquid Chromatography), while antioxidant activities were determined by seven assays (TP (Total phenolic content), TF (Total flavonoid content), DPPH (2,2-diphenyl-1-picrylhydrazyl) radical-based, ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) radical cation-based, FRAP (Ferric Reducing Antioxidant Power), TRP (Total Reducing Power), and CUPRAC (Cupric Reducing Antioxidant Capacity). The results were processed using five statistical methods (PCA (Principal Component Analysis), ANOVA (Analysis of Variance), MANOVA (Multivariate analysis of variance), DA (Discriminant analysis), and AHC (Agglomerative Hierarchical Clustering)). Principal component analysis enabled very well separation of the analyzed Artemisia species based on the content of total phenolics, total flavonoids, and the values obtained from antioxidant tests, but not on the individual compounds identified and quantified by HPLC. The MANOVA analyses showed that for A. scoparia and A. annua there was a significant effect of soil type on the total phenolics, total flavonoids, and antioxidant tests. In contrast, for A. vulgaris and A. absinthium, that effect was not significant. Additional MANOVA analyses showed a significant effect of soil type on phenolic and flavonoid compounds in the case of A. vulgaris, A. annua, and A. absinthium. The overall correct classification rate of all samples of four investigated Artemisia species by the discriminant analysis was 81.25 % using the training sample and 72.92 % the cross-validation results based on TP, TF, and antioxidant tests, but a much lower based on selected compounds identified and quantified by HPLC. MANOVA analyses based on particular Artemisia species show that soil is a significant factor affecting the measurable variables.


Asunto(s)
Antioxidantes , Artemisia , Antioxidantes/química , Quimiometría , Flavonoides/química , Fenoles/química , Extractos Vegetales/química
6.
Int J Biometeorol ; 65(1): 69-83, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31955264

RESUMEN

As an inert radioactive gas, 222Rn could be easily transported to the atmosphere via emanation, migration, or exhalation. Research measurements pointed out that 222Rn activity concentration changes during the winter and summer months, as well as during wet and dry season periods. Changes in radon concentration can affect the atmospheric electric field. At the boundary layer near the ground, short-lived daughters of 222Rn can be used as natural tracers in the atmosphere. In this work, factors controlling 222Rn pathways in the environment and its levels in soil gas and outdoor air are summarized. 222Rn has a short half-life of 3.82 days, but the dose rate due to radon and its radioactive progeny could be significant to the living beings. Epidemiological studies on humans pointed out that up to 14% of lung cancers are induced by exposure to low and moderate concentrations of radon. Animals that breed in ground holes have been exposed to the higher doses due to radiation present in soil air. During the years, different dose-effect models are developed for risk assessment on human and non-human biota. In this work are reviewed research results of 222Rn exposure of human and non-human biota.


Asunto(s)
Contaminantes Radiactivos del Aire , Monitoreo de Radiación , Radón , Contaminantes Radiactivos del Aire/análisis , Biota , Humanos , Radón/análisis , Hijas del Radón/análisis
7.
Sci Total Environ ; 733: 139271, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32446066

RESUMEN

Radioactive materials released during the two most serious nuclear accidents in history, at Chernobyl and Fukushima, caused exceptionally significant contamination and perturbations of the environment. Among them, this paper focuses on the effects related to the atmospheric electricity (AE). Measurements of the most significant disturbances in the values of various AE parameters recorded near ground level are reviewed and the corresponding results are jointly evaluated. The Chernobyl and Fukushima events caused changes in the AE parameters both after long-distance transport (Chernobyl) and short-distance transport including re-suspension (Fukushima). The data indicates that the electrical conductivity of the air is more sensitive to the presence of airborne radioactivity than the atmospheric electric potential gradient (PG). PG, on the other hand, can be monitored more easily and its variation also reflects the vertical redistribution of radionuclides in the air due to their transport, deposition, and re-suspension from the ground. A brief overview of studies on atmospheric transport and deposition of radioactive clouds is given to facilitate the importance of considering the AE measurements in these subjects, and to incorporate those studies in interpreting the results of AE measurements. The AE measurements are particularly important in studying microphysical effects of enhanced radioactivity in the air where no other distance monitoring method exists, both for fair weather conditions wet conditions.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Accidente Nuclear de Chernóbil , Accidente Nuclear de Fukushima , Monitoreo de Radiación , Radioisótopos de Cesio/análisis , Electricidad , Japón
8.
J Environ Radioact ; 158-159: 71-80, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27077326

RESUMEN

The need for reliable assessments of soil erosion rates in Serbia has directed attention to the potential for using (137)Cs measurements to derive estimates of soil redistribution rates. Since, to date, this approach has not been applied in southeastern Serbia, a reconnaissance study was undertaken to confirm its viability. The need to take account of the occurrence of substantial Chernobyl fallout was seen as a potential problem. Samples for (137)Cs measurement were collected from a zone of uncultivated soils in the watersheds of Pcinja and South Morava Rivers, an area with known high soil erosion rates. Two theoretical conversion models, the profile distribution (PD) model and diffusion and migration (D&M) model were used to derive estimates of soil erosion and deposition rates from the (137)Cs measurements. The estimates of soil redistribution rates derived by using the PD and D&M models were found to differ substantially and this difference was ascribed to the assumptions of the simpler PD model that cause it to overestimate rates of soil loss. The results provided by the D&M model were judged to more reliable.


Asunto(s)
Radioisótopos de Cesio/análisis , Modelos Teóricos , Contaminantes Radiactivos del Suelo/análisis , Suelo/química , Accidente Nuclear de Chernóbil , Monitoreo de Radiación , Ceniza Radiactiva , Ríos , Serbia
9.
Environ Sci Pollut Res Int ; 22(13): 10317-30, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25716901

RESUMEN

Primordial radionuclides, (238)U, (232)Th and (40)K were determined in soil samples collected at two depths (0-10 and 10-20 cm) in the vicinity of the largest coal-fired power plant in Serbia, and their spatial distribution was analysed using ordinary kriging. Mean values of activity concentrations for these depths were 50.7 Bq kg(-1) for (238)U, 48.7 Bq kg(-1) for (232)Th and 560 Bq kg(-1) for (40)K. Based on the measured activity concentrations, the radiological hazard due to naturally occurring radionuclides in soil was assessed. The value of the mean total absorbed dose rate was 76.3 nGy h(-1), which is higher than the world average. The annual effective dose due to these radionuclides ranged from 51.4 to 114.2 µSv. Applying cluster analysis, correlations between radionuclides and soil properties were determined. The distribution pattern of natural radionuclides in the environment surrounding the coal-fired power plant and their enrichment in soil at some sampling sites were in accordance with dispersion models of fly ash emissions. From the results obtained, it can be concluded that operation of the coal-fired power plant has no significant negative impact on the surrounding environment with regard to the content of natural radionuclides.


Asunto(s)
Monitoreo de Radiación , Radioisótopos/análisis , Contaminantes Radiactivos del Suelo/análisis , Carbón Mineral/análisis , Ceniza del Carbón , Ambiente , Centrales Eléctricas , Serbia , Suelo
10.
Environ Sci Process Impacts ; 15(6): 1279-89, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23681090

RESUMEN

In this study, the specific activity of (137)Cs was determined by gamma-ray spectrometry in 72 surface soil samples and 11 soil profiles collected from the territory of Belgrade 25 years after the Chernobyl accident. Based on the data obtained the external effective gamma dose rates due to (137)Cs were assessed and geographically mapped. The influence of pedogenic factors (pH, specific electrical conductivity, cation exchange capacity, organic matter content, soil particle size and carbonate content) on the spatial and vertical distribution of (137)Cs in soil was estimated through Pearson correlations. The specific activity of (137)Cs in surface soil samples ranged from 1.00 to 180 Bq kg(-1), with a mean value of 29.9 Bq kg(-1), while in soil profiles they ranged from 0.90 to 58.0 Bq kg(-1), with a mean value of 15.3 Bq kg(-1). The mean external effective gamma dose at 1 m above the ground due to (137)Cs in the soil was calculated to be 1.96 nSv h(-1). Geographic mapping of the external effective gamma dose rates originating from (137)Cs revealed much higher dose rates in southern parts of Belgrade city and around the confluence of the Sava and Danube. Negative Pearson correlation coefficients were found between pH, cation exchange capacity and (137)Cs specific activity in surface soil. There were positive correlations between organic matter and (137)Cs specific activity in surface soil; and between specific electrical conductivity, organic matter, silt content and (137)Cs specific activity in soil profiles.


Asunto(s)
Radioisótopos de Cesio/análisis , Contaminantes Radiactivos del Suelo/análisis , Suelo/química , Accidente Nuclear de Chernóbil , Monitoreo de Radiación , Serbia , Espectrometría gamma
11.
Environ Monit Assess ; 185(2): 1319-29, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22527467

RESUMEN

The activity concentrations of natural radionuclides in soils from the area affected by uranium mining at Stara Planina Mountain in Serbia were studied and compared with the results obtained from an area with no mining activities (background area). In the affected area, the activity concentrations ranged from 1.75 to 19.2 mg kg(-1) for uranium and from 1.57 to 26.9 mg kg(-1) for thorium which is several-fold higher than those in the background area. The Th/U, K/U, and K/Th activity ratios were also determined and compared with data from similar studies worldwide. External gamma dose rate in the air due to uranium, thorium, and potassium at 1 m above ground level in the area affected by uranium mining was found to be 91.3 nGy h(-1), i.e., about two-fold higher than that in background area. The results of this preliminary study indicate the importance of radiological evaluation of the area and implementation of remedial measures in order to prevent further dispersion of radionuclides in the environment.


Asunto(s)
Radiación de Fondo , Minería , Radioisótopos/análisis , Contaminantes Radiactivos del Suelo/análisis , Suelo/química , Uranio , Monitoreo de Radiación , Serbia
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