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1.
Cell Rep ; 43(10): 114846, 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39392751

RESUMO

Serum response factor (SRF) is a transcription factor essential for cell proliferation, differentiation, and migration and is required for primitive streak and mesoderm formation in the embryo. The canonical roles of SRF are mediated by a diverse set of context-dependent cofactors. Here, we show that SRF physically interacts with CTCF and cohesin subunits at topologically associating domain (TAD) boundaries and loop anchors. SRF promotes long-range chromatin loop formation and contributes to TAD insulation. In embryonic stem cells (ESCs), SRF associates with SOX2 and NANOG and contributes to the formation of three-dimensional (3D) pluripotency hubs. Our findings reveal additional roles of SRF in higher-order chromatin organization.


Assuntos
Cromatina , Proteína Homeobox Nanog , Fatores de Transcrição SOXB1 , Fator de Resposta Sérica , Fator de Resposta Sérica/metabolismo , Cromatina/metabolismo , Animais , Camundongos , Proteína Homeobox Nanog/metabolismo , Proteína Homeobox Nanog/genética , Fatores de Transcrição SOXB1/metabolismo , Fatores de Transcrição SOXB1/genética , Fator de Ligação a CCCTC/metabolismo , Humanos , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Pluripotentes/citologia , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Coesinas , Diferenciação Celular , Ligação Proteica , Células-Tronco Embrionárias/metabolismo , Células-Tronco Embrionárias/citologia
2.
Entropy (Basel) ; 26(10)2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39451892

RESUMO

We present a comparative analysis of the plethora of nonextensive and/or nonadditive entropies which go beyond the standard Boltzmann-Gibbs formulation. After defining the basic notions of additivity, extensivity, and composability, we discuss the properties of these entropies and their mutual relations, if they exist. The results are presented in two informative tables that are of strong interest to the gravity and cosmology community in the context of the recently intensively explored horizon entropies for black hole and cosmological models. Gravitational systems admit long-range interactions, which usually lead to a break of the standard additivity rule for thermodynamic systems composed of subsystems in Boltzmann-Gibbs thermodynamics. The features of additivity, extensivity, and composability are listed systematically. A brief discussion on the validity of the notion of equilibrium temperature for nonextensive systems is also presented.

3.
Environ Pollut ; : 125114, 2024 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-39401557

RESUMO

Northeast Asia suffers from high concentrations of particulate matter (PM), prompting nations to actively implement emission reduction policies. This study evaluated the recent inter-annual changes in the chemical transformation and transboundary transport of PM over Northeast Asia, based on both ground and aircraft measurements, as well as WRF-Chem simulations, during two comprehensive campaigns: the Korea-United States Air Quality (KORUS-AQ) campaign in 2016 and the Satellite Integrated Joint Monitoring of Air Quality (SIJAQ) campaign in 2022, both conducted around the Korean Peninsula. Ground measurements in 2022 revealed significant reductions in air pollutants compared to 2016 levels. In the Beijing-Tianjin-Hebei region, PM2.5 and SO2 concentrations decreased by 47.2% and 73.9%, respectively, attributable to successful SOx and NOx emission reduction strategies. Similar trends were observed in downwind areas, including Seoul, where PM2.5 and SO2 levels declined by 30.0% and 41.4%, respectively. WRF-Chem model results indicated substantial decreases in sulfates, nitrates, and their precursors in both surface and upper atmosphere in 2022 compared to 2016. Moreover, model-calculated gas-to-particle conversion ratios, which peaked in the Yellow Sea in 2016, decreased by 15% in 2022 and shifted slightly eastward to the western Korean Peninsula. This shift suggests a potential decline in secondary PM formation processed in the Yellow Sea, coinciding with reduced long-range transport of gaseous pollutants. A comparison of model sensitivity experiments, accounting for both bottom-up emission changes and meteorological variations, revealed that while weather and climate factors such as precipitation and pressure patterns between 2016 and 2022 contributed to the overall decrease in PM concentrations, the primary driver was the reduction in emissions during this period. This study highlighted that the main driver of the substantial improvement in air quality over East Asia was the implementation of emission reduction policies targeting PM and its precursors in the main source regions in China.

4.
Heliyon ; 10(19): e38211, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39386778

RESUMO

This paper applies fractional integration to investigate the behaviour of various pollutants in seven Chinese cities. The objective is to establish if the series exhibit long memory and if time trends are statistically significant over the sample period going from January 2014 to November 2022. The results suggest that the steps recently taken by the Chinese authorities to reduce emissions and improve air quality have already had some effect: in most cases the air pollutant series are in the stationary range, with mean reversion occurring and shocks only having temporary effects, and there are significant downward trends indicating a decline over time in the degree of pollution in China. It is also interesting that in the most recent period, the Zero-Covid policy of the Chinese authorities has led to a further fall. On the whole, it would appear that the action plan adopted by the Chinese government is bringing the expected environmental benefits and therefore it is to be hoped that such policies will continue to be implemented and extended to improve air quality even further.

5.
J Hazard Mater ; 480: 136126, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39423647

RESUMO

Microplastic (MP) transport in the atmosphere, one of the least studied environmental compartments because of the relatively small size of air-borne MPs and the challenges in identifying them, may be inferred from their occurrence in snowfall. In this study, 11 sites across western coastal North America were sampled and analyzed for MP presence in fresh snowfall, months-old summer surface snow, and stratified deposits in snow pits. MPs were detected and characterized using a method integrating linear array µ-Fourier Transform Spectroscopy (µFTIR) and batch spectral analysis with open-source platform Open Specy. Recovery rate analysis from sample filtration to data analysis was conducted, and analysis of field or laboratory blanks suggested negligible contamination (≤ 1 polyamide fragment per blank). Concentrations of MPs in the fresh snowfall of remote sites and those proximal to sources were 5.1-150.8 p/L and 104.5-325 p/L of snowmelt water, respectively. Summer surface snow that was several months old had MP concentrations ranging from 57.5-539 p/L of meltwater, and snow sampled at different depths within a snowpack had concentrations ranging from 35-914 p/L. Our results demonstrate a streamlined method that may be used for measuring MPs in remote or pristine environments, contributing to a better understanding of long-range MP transport.

6.
Environ Pollut ; 363(Pt 1): 125100, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39389244

RESUMO

This study investigates the presence, distribution, and potential impacts of perfluoroalkyl substances (PFASs) and hexabromocyclododecanes (HBCDs) on the Antarctic marine environment. The analysis results from the King Sejong Station, the Jang Bogo Station, and Cape Evans revealed the highest concentrations of both PFASs and HBCDs at King Sejong Station, indicating the significant influence of human activity. Short-chain perfluorocarboxylic acids (PFCAs) dominated the seawater samples, with PFPeA at the highest concentration (0.076 ng/L) at King Sejong Station, whereas perfluorosulfonic acids (PFSAs) were prevalent in the sediments, with PFHxS reaching 0.985 ng/g. Total PFASs in benthos ranged from N.D. to 2.40 ng/g ww across all stations. This indicated the effects of long-range transport and glacial meltwater. α-HBCD was the most common diastereomer in benthos samples, detected in 58.3% of samples, suggesting its selective persistency. Although risk quotient analysis revealed low immediate risks to lower-trophic organisms, potential risks remain owing to their persistence and bioaccumulation potential. Contaminant patterns changed after regulations: perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) levels decreased, unregulated PFASs increased, HBCD stereoisomer ratios shifted towards α-HBCD dominance, and overall HBCD concentrations declined. Widespread persistence of regulated substances was observed in Antarctic environments, highlighting the need for comprehensive and long-term monitoring strategies. This study provides essential baseline data on contaminant distributions across the Southern Ocean, contributing to our understanding of emerging pollutants in Antarctic regions and informing future environmental protection efforts.

7.
Cell Genom ; : 100674, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39406235

RESUMO

The Long-Read Personalized OncoGenomics (POG) dataset comprises a cohort of 189 patient tumors and 41 matched normal samples sequenced using the Oxford Nanopore Technologies PromethION platform. This dataset from the POG program and the Marathon of Hope Cancer Centres Network includes DNA and RNA short-read sequence data, analytics, and clinical information. We show the potential of long-read sequencing for resolving complex cancer-related structural variants, viral integrations, and extrachromosomal circular DNA. Long-range phasing facilitates the discovery of allelically differentially methylated regions (aDMRs) and allele-specific expression, including recurrent aDMRs in the cancer genes RET and CDKN2A. Germline promoter methylation in MLH1 can be directly observed in Lynch syndrome. Promoter methylation in BRCA1 and RAD51C is a likely driver behind homologous recombination deficiency where no coding driver mutation was found. This dataset demonstrates applications for long-read sequencing in precision medicine and is available as a resource for developing analytical approaches using this technology.

8.
Neurosci Lett ; 842: 138008, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39369840

RESUMO

Unperceivable electrical noise stimulation has been applied to improve postural control through the enhancement of somatosensory feedback. It has been observed that stimulation with a pink noise (1/f) structure is more effective than stimulation with other noise structures. In addition, the 1/f structure embedded in the postural control system may have a superior effect on postural control stabilization. However, the direct relationship between the long-range correlations of the pink-noise signal applied to somatosensory receptors and those of the postural control system has not been elucidated. Thus, we aimed to explore a common long-range correlation factor shared in the time series of the provided noise and foot center of pressure (CoP) during quiet standing. Sixteen young adults stood quietly on the force platform for 65 s. Four noise conditions (no stimulation and stimulation of knee joints with white-, pink-, and red-noise-like signals) were employed during the standing trials. The detrending moving-average cross-correlation analysis revealed that in each of the anteroposterior and mediolateral directions, the CoP velocity time series displayed significant long-range cross-correlations with the white and pink noise signals provided at that time, whereas such an effect was not observed in the red noise signal. This result indicates that pink and white noise signals would alter the temporal behavior of the CoP during quiet standing, although the mechanism remains to be elucidated.


Assuntos
Equilíbrio Postural , Posição Ortostática , Humanos , Masculino , Adulto Jovem , Feminino , Equilíbrio Postural/fisiologia , Adulto , Pressão , Estimulação Elétrica/métodos , Retroalimentação Sensorial/fisiologia
9.
J Phys Condens Matter ; 36(50)2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39319590

RESUMO

In this paper we investigate the interconnection between vacancy-ordered phases and vacancy self-diffusion. Here, we investigate three ordered phases on a square lattice with energetics defined by two separate Hamiltonians. In the first case we used a classical antiferromagnetic Ising model Hamiltonian in order to generate a 'checkerboard' type ordered structure. In the second case, we used a modified Ising model with competing influence of second and third nearest-neighbors, which resulted in both 'hatch' and 'labyrinthine' structures, depending on concentration. To understand how vacancy-ordering affects diffusion, we determined the tracer diffusivity using rejection-free kinetic Monte Carlo and compared disordered and ordered structures. Finally, we developed an analytical model describing diffusion in the ordered 'checkerboard' structure and found that it was able to predict apparent activation energies in the ordered and disordered structures. Our results suggest that it is short-range order rather than long-range order that most significantly affects tracer diffusion.

10.
Cureus ; 16(8): e66911, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39280511

RESUMO

In Hungary, possessing certain weapons (e.g. firearms, bows, air pistols, and air guns mainly over 7.5 Joule muzzle velocity) is strictly regulated. In case of firearm deaths, in our country, we usually have to consider the role of military personnel or a hunter. Getting a game license for five years is a complex procedure. Class participation in weapon training, hunter ethics, and rules, first aid, manners of hunting, wild animals' knowledge, wildlife management, game laws, etc. is compulsory besides a prosperous exam at the Hunt Authority. A psychological license is also mandatory. Through permission from the police for a firearm license, buying weapons for hunting is possible. The storage of firearms and cartridges is rigidly controlled and checked. Some special types of hunting (e.g. with a bow, bird of prey) require additional licenses. The fact and the duration of the hunt and all shoots should be registered. The authors report an extraordinary fatal hunting accident because of non-regulation rifle (Blaser R8 338) use (unintentional shot), in which the travel distance of the projectile was more than 2000 m and the victim suffered fatal injuries at his daughter's homeyard. This was a non-target, extreme long-range shot. The ethical range in hunting is within 150 m, a practiced hunter with proper precision tools can shoot accurately within 300-400 m and in extremely rare cases within 700-800 m. Military snipers can operate over a 1000 m distance. Even if this was a targeted shot (with a 2161 m range), not many professionals would have been able to aim at the target. A sequence of accidents was necessary for this fatal case. With the application of X-ray examination and a special layer-by-layer method of forensic autopsy, the bullet, the entry wound, the primary shot channel, and lethal injuries have been revealed. With the help of the found projectile and the rigorous hunting regulations, the alleged perpetrator was identified within a short time.

11.
Front Comput Neurosci ; 18: 1388224, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39281981

RESUMO

Introduction: Electrical stimulation of the brain has shown promising prospects in treating various brain diseases. Although biphasic pulse stimulation remains the predominant clinical approach, there has been increasing interest in exploring alternative stimulation waveforms, such as sinusoidal stimulation, to improve the effectiveness of brain stimulation and to expand its application to a wider range of brain disorders. Despite this growing attention, the effects of sinusoidal stimulation on neurons, especially on their nonlinear firing characteristics, remains unclear. Methods: To address the question, 50 Hz sinusoidal stimulation was applied on Schaffer collaterals of the rat hippocampal CA1 region in vivo. Single unit activity of both pyramidal cells and interneurons in the downstream CA1 region was recorded and analyzed. Two fractal indexes, namely the Fano factor and Hurst exponent, were used to evaluate changes in the long-range correlations, a manifestation of nonlinear dynamics, in spike sequences of neuronal firing. Results: The results demonstrate that sinusoidal electrical stimulation increased the firing rates of both pyramidal cells and interneurons, as well as altered their firing to stimulation-related patterns. Importantly, the sinusoidal stimulation increased, rather than decreased the scaling exponents of both Fano factor and Hurst exponent, indicating an increase in the long-range correlations of both pyramidal cells and interneurons. Discussion: The results firstly reported that periodic sinusoidal stimulation without long-range correlations can increase the long-range correlations of neurons in the downstream post-synaptic area. These results provide new nonlinear mechanisms of brain sinusoidal stimulation and facilitate the development of new stimulation modes.

12.
Mol Genet Metab Rep ; 41: 101139, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39282050

RESUMO

Mucopolysaccharidosis II (MPS II) is a lysosomal storage disease caused by a deficiency in iduronate-2-sulfatase (IDS), leading to the accumulation of dermatan sulfate and heparan sulfate in lysosomes. Traditionally, genotyping of the IDS gene has been conducted through exome sequencing, which fails to detect inversion variants. Consequently, when no pathogenic variants are detected in exons, additional PCR-based analysis is required. Herein, we introduce a rapid genotyping technique method using long-range PCR for MPS II patients. We successfully identified an inversion variant and confirmed the sequences of the inversion regions. We also confirmed that the pathogenic variant in the patient originated de novo. These findings suggest that long-range PCR genotyping can identify inversion variants more rapidly compared to the previous PCR-based methods, making it a valuable tool for newborn screening (NBS) and genetic diagnosis.

13.
Entropy (Basel) ; 26(9)2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39330110

RESUMO

Tsallis entropy has been widely used in image thresholding because of its non-extensive properties. The non-extensive parameter q contained in this entropy plays an important role in various adaptive algorithms and has been successfully applied in bi-level image thresholding. In this paper, the relationships between parameter q and pixels' long-range correlations have been further studied within multi-threshold image segmentation. It is found that the pixels' correlations are remarkable and stable for images generated by a known physical principle, such as infrared images, medical CT images, and color satellite remote sensing images. The corresponding non-extensive parameter q can be evaluated by using the self-adaptive Tsallis entropy algorithm. The results of this algorithm are compared with those of the Shannon entropy algorithm and the original Tsallis entropy algorithm in terms of quantitative image quality evaluation metrics PSNR (Peak Signal-to-Noise Ratio) and SSIM (Structural Similarity). Furthermore, we observed that for image series with the same background, the q values determined by the adaptive algorithm are consistently kept in a narrow range. Therefore, similar or identical scenes during imaging would produce similar strength of long-range correlations, which provides potential applications for unsupervised image processing.

14.
Neural Netw ; 180: 106697, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39305784

RESUMO

Local feature extraction plays a crucial role in numerous critical visual tasks. However, there remains room for improvement in both descriptors and keypoints, particularly regarding the discriminative power of descriptors and the localization precision of keypoints. To address these challenges, this study introduces a novel local feature extraction pipeline named OSDFeat (Object and Spatial Discrimination Feature). OSDFeat employs a decoupling strategy, training descriptor and detection networks independently. Inspired by semantic correspondence, we propose an Object and Spatial Discrimination ResUNet (OSD-ResUNet). OSD-ResUNet captures features from the feature map that differentiate object appearance and spatial context, thus enhancing descriptor performance. To further improve the discriminative capability of descriptors, we propose a Discrimination Information Retained Normalization module (DIRN). DIRN complementarily integrates spatial-wise normalization and channel-wise normalization, yielding descriptors that are more distinguishable and informative. In the detection network, we propose a Cross Saliency Pooling module (CSP). CSP employs a cross-shaped kernel to aggregate long-range context in both vertical and horizontal dimensions. By enhancing the saliency of keypoints, CSP enables the detection network to effectively utilize descriptor information and achieve more precise localization of keypoints. Compared to the previous best local feature extraction methods, OSDFeat achieves Mean Matching Accuracy of 79.4% in local feature matching task, improving by 1.9% and achieving state-of-the-art results. Additionally, OSDFeat achieves competitive results in Visual Localization and 3D Reconstruction. The results of this study indicate that object and spatial discrimination can improve the accuracy and robustness of local feature, even in challenging environments. The code is available at https://github.com/pandaandyy/OSDFeat.

15.
PNAS Nexus ; 3(9): pgae329, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39238605

RESUMO

City systems are characterized by the functional organization of cities on a regional or country scale. While there is a relatively good empirical and theoretical understanding of city size distributions, insights about their spatial organization remain on a conceptual level. Here, we analyze empirically the correlations between the sizes of cities (in terms of area) across long distances. Therefore, we (i) define city clusters, (ii) obtain the neighborhood network from Voronoi cells, and (iii) apply a fluctuation analysis along all shortest paths. We find that most European countries exhibit long-range correlations but in several cases these are anti-correlations. In an analogous way, we study a model inspired by Central Places Theory and find that it leads to positive long-range correlations, unless there is strong additional spatial disorder-contrary to intuition. We conclude that the interactions between cities extend over large distances reaching the country scale. Our findings have policy relevance as urban development or decline can affect cities at a considerable distance.

16.
Sci Rep ; 14(1): 21957, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39304663

RESUMO

Spiking neural networks (SNNs) take inspiration from the brain to enable energy-efficient computations. Since the advent of Transformers, SNNs have struggled to compete with artificial networks on modern sequential tasks, as they inherit limitations from recurrent neural networks (RNNs), with the added challenge of training with non-differentiable binary spiking activations. However, a recent renewed interest in efficient alternatives to Transformers has given rise to state-of-the-art recurrent architectures named state space models (SSMs). This work systematically investigates, for the first time, the intersection of state-of-the-art SSMs with SNNs for long-range sequence modelling. Results suggest that SSM-based SNNs can outperform the Transformer on all tasks of a well-established long-range sequence modelling benchmark. It is also shown that SSM-based SNNs can outperform current state-of-the-art SNNs with fewer parameters on sequential image classification. Finally, a novel feature mixing layer is introduced, improving SNN accuracy while challenging assumptions about the role of binary activations in SNNs. This work paves the way for deploying powerful SSM-based architectures, such as large language models, to neuromorphic hardware for energy-efficient long-range sequence modelling.

17.
Sci Total Environ ; 954: 176274, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39304148

RESUMO

This cross-cutting review focuses on the presence and impacts of per- and polyfluoroalkyl substances (PFAS) in the Arctic. Several PFAS undergo long-range transport via atmospheric (volatile polyfluorinated compounds) and oceanic pathways (perfluorinated alkyl acids, PFAAs), causing widespread contamination of the Arctic. Beyond targeting a few well-known PFAS, applying sum parameters, suspect and non-targeted screening are promising approaches to elucidate predominant sources, transport, and pathways of PFAS in the Arctic environment, wildlife, and humans, and establish their time-trends. Across wildlife species, concentrations were dominated by perfluorooctane sulfonic acid (PFOS), followed by perfluorononanoic acid (PFNA); highest concentrations were present in mammalian livers and bird eggs. Time trends were similar for East Greenland ringed seals (Pusa hispida) and polar bears (Ursus maritimus). In polar bears, PFOS concentrations increased from the 1980s to 2006, with a secondary peak in 2014-2021, while PFNA increased regularly in the Canadian and Greenlandic ringed seals and polar bear livers. Human time trends vary regionally (though lacking for the Russian Arctic), and to the extent local Arctic human populations rely on traditional wildlife diets, such as marine mammals. Arctic human cohort studies implied that several PFAAs are immunotoxic, carcinogenic or contribute to carcinogenicity, and affect the reproductive, endocrine and cardiometabolic systems. Physiological, endocrine, and reproductive effects linked to PFAS exposure were largely similar among humans, polar bears, and Arctic seabirds. For most polar bear subpopulations across the Arctic, modeled serum concentrations exceeded PFOS levels in human populations, several of which already exceeded the established immunotoxic thresholds for the most severe risk category. Data is typically limited to the western Arctic region and populations. Monitoring of legacy and novel PFAS across the entire Arctic region, combined with proactive community engagement and international restrictions on PFAS production remain critical to mitigate PFAS exposure and its health impacts in the Arctic.

18.
Angew Chem Int Ed Engl ; : e202411603, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39231800

RESUMO

Non-iridium acid-stabilized electrocatalysts for oxygen evolution reaction (OER) are crucial to reducing the cost of proton exchange membrane water electrolyzers (PEMWEs). Here, we report a strategy to modulate the stability of RuO2 by doping boron (B) atoms, leading to the preparation of a RuO2 catalyst with long-range disorder (LD-B/RuO2). The structure of long-range disorder endowed LD-B/RuO2 with a low overpotential of 175 mV and an ultra-long stability, which can maintain OER for about 1.6 months at 10 mA cm-2 current density in 0.5 M H2SO4 with almost invariable performance. More importantly, a PEM electrolyzer using LD-B/RuO2 as the anode demonstrated excellent performance, reaching 1000 mA cm-2 at 1.63 V with durability exceeding 300 h at 250 mA cm-2 current density. The introduction of B atoms induced the formation of a long-range disordered structure and symmetry-breaking B-Ru-O motifs, which enabled the catalyst structure to a certain toughness while simultaneously inducing the redistribution of electrons on the active center Ru, which jointly promoted and guaranteed the activity and long-term stability of LD-B/RuO2. This study provides a strategy to prepare long-range disordered RuO2 acidic OER catalysts with high stability using B-doping to perturb crystallinity, which opens potential possibilities for non-iridium-based PEMWE applications.

19.
Environ Sci Pollut Res Int ; 31(40): 53304-53314, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39186206

RESUMO

This study focuses on the chemical composition of cloud water (CW) and rainwater (RW) collected at Sinhagad, a high-altitude station (1450 m AMSL) located in the western region of India. The samples were collected during the monsoon over two years (2016-2017). The chemical analysis suggests that the concentration of total ionic constituents was three times higher in CW than in RW, except for NH4+ (1.0) and HCO3- (0.6). Compared to RW, high concentrations of SO42- and NO3- were observed in CW. The weighted average RW pH (6.5 ± 0.3) was slightly more alkaline than CW pH (6.1 ± 0.5). This can be attributed to the high concentrations of neutralizing ions such as nss-Ca2+, nss-Mg2+, K+, and NH4+, indicating the greater extent of wet scavenging during rainfall. These ions counteract the acidity generated by SO42- and NO3-. A high correlation between Ca2+, Na+, K+, NO3-, and SO42- makes it difficult to estimate the contribution of SO42- from different sources. Anthropogenic sulfur emissions and soil dust significantly influence the ionic composition of clouds and rain. Positive matrix factorization (PMF) was used to identify the contribution of different sources to the samples. In the CW, the extracted factors were cooking and vehicles, aging sea salt, agriculture, and dust. In RW, the factors were industries, cooking and vehicles, agriculture and dust, and aging sea salt. The findings of this study have significant implications for the monsoon build-up, ecosystems, agriculture, and climate change.


Assuntos
Altitude , Monitoramento Ambiental , Chuva , Índia
20.
J Hazard Mater ; 478: 135459, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39137552

RESUMO

Understanding the occurrence and fate of current-use pesticides (CUPs) in coastal and open marine waters is essential for conducting exposure and risk assessments to ensure the protection of marine ecosystems from chemical pollution. While CUPs have been frequently studied in freshwater systems, knowledge of their behavior in marine environments remains fragmentary. This study investigated 28 CUPs across 50 sites along a transect from the Baltic outflow to pristine Arctic waters using ships of opportunity with installed FerryBox system. Overall, 14 CUPs were detected at least at one site at concentrations ranging from sub-ng/L to ng/L. CUP concentrations were higher in the Baltic outflow and decreased along the transect. Atrazine, simazine, tebuconazole, and propiconazole were detected in > 40 % of samples, including remote open sea regions, suggesting their potential for long-range marine transport. This Baltic Sea was identified as a major source of CUPs to connected marine systems. Additional CUPs were detected in the Baltic outflow, encompassing diuron, isoproturon, metazachlor, metolachlor, pyrazon, terbuthylazine, and chlortoluron. Ecotoxicological assessment indicated a moderate risk posed by metolachlor to algae. The use of the described infrastructure holds great promise for advancing our understanding of the occurrence and fate of CUPs in marine environments.


Assuntos
Monitoramento Ambiental , Praguicidas , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Praguicidas/análise , Monitoramento Ambiental/métodos , Regiões Árticas , Água do Mar/química , Água do Mar/análise , Europa (Continente) , Triazóis/análise
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