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1.
Sci Total Environ ; 912: 169256, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38101629

RESUMEN

A pioneering study employed a holistic geostatistical approach to predict the spatial variability of a non sampled area in the Chenab River, Pakistan, using kriging interpolation for organochlorine pesticide (OCP)-polluted risk zones. The Present research intended to investigate the carcinogenic and non-carcinogenic human health risks, contamination levels, and spatial variation of OCPs in the Chenab River, Pakistan. The residual OCP content in sediment samples (n = 120) ranged from 0.056 to 32.14 ng/g. DDE and α-HCH were prevalent among all the samples analyzed, with mean concentrations of 15.84 ± 8.02 and 12.45 ± 6.72 ng/g, respectively. The order of magnitude of OCPs in sediment samples was DDTs > α-HCH > chlorothalonil > heptachlor > endosulfan > aldrin > dieldrin. The findings of the single (SPI) and Nemerow (Nel) pollution index of α-HCH, heptachlor, and aldrin depicted the Chenab River as a serious pollution risk zone. The outcomes of the Pearson correlation coefficient analysis represent the positive correlation among all OCPs, revealing the common origin. Distribution trends showed substantially higher (p < 0.05) contents of analyzed OCPs along the downstream zone. With regards to USEPA human health hazard assessment model, the estimated non-carcinogenic (ΣHI) and non-carcinogenic (ΣTCR) risk ranged from 1.1 × 10-5 to 1.0 × 10-1, 4.0 × 10-8 to 3.2 × 10-4 respectively. TCR >10-4 illustrated a substantial cancer health risk posed by α-HCH, heptachlor, aldrin, and dieldrin in the downstream zone. We recommend the urgent cessation of the ongoing discharge of OCPs into the Chenab River, which needs to be highlighted owing to the significant cancer risk to public health to ensure the good health and wellbeings.


Asunto(s)
Hexaclorociclohexano , Hidrocarburos Clorados , Neoplasias , Plaguicidas , Contaminantes Químicos del Agua , Humanos , Dieldrín/análisis , Aldrín/análisis , Monitoreo del Ambiente , Plaguicidas/análisis , Hidrocarburos Clorados/análisis , Heptacloro/análisis , Contaminantes Químicos del Agua/análisis , China
2.
PLoS One ; 18(9): e0289069, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37708189

RESUMEN

Heavy metal contamination of water has become a global environmental burden, which has stirred up agitation worldwide. Fabrication of adsorbents utilizing either low cost, environment friendly materials or waste products can be helpful in remediating environmental pollution. The current study evolved around the synthesis of nanocomposites derived from such raw precursors like spent tea waste biochar, hydroxyapatite, and clays. In this context, two nanocomposites, namely manganese ferrite doped hydroxyapatite/kaolinite/biochar (TK-NC) and manganese ferrite doped hydroxyapatite/vermiculite/biochar (TV-NC), were synthesized followed by their employment for decontamination of heavy metals from aqueous media. TK-NC and TV-NC exhibited the crystallite sizes in the range of 2.55-5.94 nm as obtained by Debye Scherrer Equation and Williamsons-Hall equation The fabricated nanocomposites were characterized using FT-IR, SEM-EDX, and powder XRD. Batch adsorption studies were performed, and influence of different adsorption parameters (contact time, reaction temperature, solution pH, adsorbent dose, and initial adsorbate concentration) on metal adsorption was examined. Thermodynamic studies revealed that the adsorption of Cr(VI), Ni(II) and Cu(II) on TK-NC and TV-NC was endothermic (+ΔH°) and indicates disorderness (+ΔS°) at the solid-liquid interface owing to the strong affinity of metal ions with adsorbent. The heavy metal uptake selectivity followed the following decreasing order; Cr(VI) > Cu(II) > Ni(II) by both nanocomposites, with adsorption capacities falling in the range of 204.68-343.05 mg g-1. Several adsorption kinetic and isotherm models were applied to experimentally calculated data, which suggest favorable adsorption of Cr(VI), Ni(II) and Cu(II) by TK-NC and TV-NC from the system while obeying general-order kinetics and R-P adsorption model, conferring the transition in adsorption kinetics order and involvement of multiple adsorption process.


Asunto(s)
Metales Pesados , Agua , Descontaminación , Espectroscopía Infrarroja por Transformada de Fourier , Durapatita
3.
Sci Total Environ ; 882: 163504, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37080307

RESUMEN

Carcinogenic hazards to human health were investigated through oral and dermal exposure to organochlorine pesticides (OCPs) from water samples (n = 120) of River Chenab, Pakistan. The Pioneering study aimed to employ an integrated geographic information system (GIS) based geostatistical method for the determination of pollution load by GC-ECD from water of River Chenab. The residual levels of OCPs detected from water samples ranged from 0.54 to 122 ng L-1 with significant prevalence of DDE and α-HCH. Results of the Nemerrow pollution index (NeI), single pollution index (SPI), and comprehensive pollution index (CPI) reflected the downstream zone a stern pollution risk zone. The spatial distribution pattern through geostatistical approaches also revealed significantly higher (p < 0.05) OCP levels in the downstream zone. Risk quotient (RQCCC) of surface water quality with respect to heptachlor epitomized a high level of risk (RQCCC > 1). Non-carcinogenic human health risk (Σ HQ) assessment ranged from 8.39 × 10-9 to 1.7 × 10-3, which represented a marginal risk through oral and dermal exposure. However, carcinogenic risks by oral exposure route were ranged from 3.57 × 10-11 to 4.46 × 10-6. Estimated cancer risk (ΣCR) exhibited a considerable carcinogenic risk posed by heptachlor, α-HCH and dieldrin. It is suggested to employ an immediate mitigation strategy for the constant discharge of OCPs in the studied area.


Asunto(s)
Hidrocarburos Clorados , Plaguicidas , Contaminantes Químicos del Agua , Humanos , Pakistán , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Plaguicidas/análisis , Hidrocarburos Clorados/análisis , Medición de Riesgo , Heptacloro , Calidad del Agua , China
4.
Sci Total Environ ; 871: 162084, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-36758692

RESUMEN

The present study was conducted to evaluate Carcinogenic (TR) and non-carcinogenic (THQ) human health risk of organochlorine pesticides (OCPs) in three edible fish species (Labeo boga, Channa marulius and Wallago attu) of River Chenab, Pakistan using USEPA human health risk assessment model. Holistic GIS (Geographic information system) based Geo-Statistical approach has been employed for the first time in River Chenab, Pakistan to categorize contaminated risk zones of OCPs based on single pollution index. The ∑OCPs concentrations in fish species were ranged from 5.09 to 414 ng/g with the prevalence of dieldrin. Results of single pollution index of DDE, aldrin, dieldrin and ∑endosulfan revealed River Chenab as polluted and risk zone area. Distribution pattern assessed significantly higher (p < 0.05) concentrations of OCPs in downstream area suggesting substantial pollution of surrounded industrial region. The human health risk assessment depicted no harmful non-carcinogenic (THQ) risk except for ΣOCPs concentration of C. marulius. Significant carcinogenic (TR) health risk exhibited by all examined OCPs from maximum of the studied sites. Therefore, the high carcinogenic human health risk had highlighted an immediate removal of continuous disposal of OCPs in the River Chenab.


Asunto(s)
Cyprinidae , Hidrocarburos Clorados , Plaguicidas , Contaminantes Químicos del Agua , Animales , Humanos , Sistemas de Información Geográfica , Dieldrín , Pakistán , Contaminantes Químicos del Agua/análisis , Plaguicidas/análisis , Hidrocarburos Clorados/análisis , Carcinógenos , Medición de Riesgo , Monitoreo del Ambiente/métodos
5.
Environ Sci Pollut Res Int ; 30(15): 44795-44818, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36697982

RESUMEN

The alarming impact of climate change and environmental pollutants has increased the focus of policymakers and think tanks' focus on formulating environmental regulations. Environmental regulations may reduce emissions directly and indirectly, as postulated by the famous Porter Hypothesis. It shows that environmental regulation may enhance pollution-reducing innovation by reducing agency costs while at the same time increasing firms' private benefit. The study is designed to investigate environmental regulations' direct and indirect impact on CO2 and GHG emissions using innovations as mediation factors. The study employs a structural equation method using data on G7 economies from 1990 to 2020 to test the relationship between regulations, innovations, and pollution. The study findings confirm that environmental regulations help reduce emissions directly. Our findings also confirm the Porter hypothesis whereby regulations encourage innovations and result in reduced emissions through this indirect channel. The study findings have significant implications for controlling pollution through placing environmental regulations and encouraging innovations.


Asunto(s)
Desarrollo Económico , Contaminación Ambiental , Contaminación Ambiental/análisis , China , Dióxido de Carbono/análisis
6.
Sensors (Basel) ; 22(23)2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36501853

RESUMEN

Major challenges affecting polarizers for communication systems include the inability to perform over a wide bandwidth with a simple design. Orthogonal outgoing polarization for polarization-diverse applications and stable performances for oblique incidence angles are also major requirements. This paper presents the design of a polarizer that can perform over a wide range of bandwidths in dual frequency bands. The unit cell is uniquely designed using a split circular ring resonator enclosed in a square ring with the addition of three-square patches. As a result, the incoming linearly polarized x(y) wave is converted into a transmitted LHCP (RHCP) wave in the Ku and Ka bands. The operational bandwidths are 11.05~16.75 GHz (41%) and 34.16~43.03 GHz (23%). The proposed polarizer is ultrathin, works in dual wide-bands, is polarization-diverse, and maintains performance over ±45° and ±30° oblique incidences, which makes it a strong candidate for many communication systems.

7.
Nanomaterials (Basel) ; 12(10)2022 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-35630935

RESUMEN

Metasurfaces, a special class of metamaterials, have recently become a rapidly growing field, particularly for thin polarization converters. They can be fabricated using a simple fabrication process due to their smaller planar profile, both in the microwave and optical regimes. In this paper, the recent progress in MSs for linear polarization (LP) to circular polarization (CP) conversion in transmission mode is reviewed. Starting from history, modeling and the theory of MSs, uncontrollable single and multiple bands and LP-to-CP conversions, are discussed and analyzed. Moreover, detailed reconfigurable MS-based LP-to-CP converters are presented. Further, key findings on the state-of-the-arts are discussed and tabulated to give readers a quick overview. Finally, a conclusion is drawn by providing opinions on future developments in this growing research field.

8.
Saudi Pharm J ; 30(12): 1700-1709, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36601499

RESUMEN

Skin, largest organ of human, is directly exposed to environment and hence is prone to high rates of injuries and microbial infections. Over the passage of time these microbes have developed resistance to antibiotics making them ineffective especially in lower doses and hence, higher dosages or new drugs are required. The current study deals with designing of nano-emulsion (NE) formulations composed of garlic and ginger oils (0.1 %) with neomycin sulphate used in different ratios (0.001, 0.01 and 0.1 %) and combinations. The resulting NEs were characterized for droplet size (145-304 nm), zetapotential (-3.0-0.9 mV), refractive index (1.331-1.344), viscosity (1.10-1.23cP), transmittance (96-99 %), FT-IR and HPLC and found stable over a period of three months. All NEs were also found effective against both gram positive and negative bacterial strains i.e., B. spizizenii, S. aureus, E. coli and S. enterica as compared to pure neomycin sulphate (NS) used as control with highest activity recorded for NE-2 and NE-4 against all strains showing zone of inhibition in range of 22-30 mm and 21-19 mm, respectively. NEs were also tested using rabbit skin excision wound model which potentiates that all the NEs resulted in early recovery with 86-100 % wound healing achieved in 9 days as compared to NS ointment (71 %). The studies confirmed that essential oils when used in combination with traditional drug can lead to much higher efficacies as compared to pure drugs.

9.
Sci Rep ; 11(1): 7802, 2021 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-33833285

RESUMEN

Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) enable human cardiac cells to be studied in vitro, although they use glucose as their primary metabolic substrate and do not recapitulate the properties of adult cardiomyocytes. Here, we have explored the interplay between maturation by stimulation of fatty acid oxidation and by culture in 3D. We have investigated substrate metabolism in hiPSC-CMs grown as a monolayer and in 3D, in porous collagen-derived scaffolds and in engineered heart tissue (EHT), by measuring rates of glycolysis and glucose and fatty acid oxidation (FAO), and changes in gene expression and mitochondrial oxygen consumption. FAO was stimulated by activation of peroxisome proliferator-activated receptor alpha (PPARα), using oleate and the agonist WY-14643, which induced an increase in FAO in monolayer hiPSC-CMs. hiPSC-CMs grown in 3D on collagen-derived scaffolds showed reduced glycolysis and increased FAO compared with monolayer cells. Activation of PPARα further increased FAO in cells on collagen/elastin scaffolds but not collagen or collagen/chondroitin-4-sulphate scaffolds. In EHT, FAO was significantly higher than in monolayer cells or those on static scaffolds and could be further increased by culture with oleate and WY-14643. In conclusion, a more mature metabolic phenotype can be induced by culture in 3D and FAO can be incremented by pharmacological stimulation.


Asunto(s)
Medios de Cultivo/metabolismo , Ácidos Grasos/metabolismo , Glucosa/metabolismo , Células Madre Pluripotentes Inducidas , Miocitos Cardíacos , Diferenciación Celular , Células Cultivadas , Humanos , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/metabolismo , Miocitos Cardíacos/citología , Miocitos Cardíacos/metabolismo
10.
J Funct Biomater ; 12(1)2021 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-33803209

RESUMEN

In addition to biocompatibility, an ideal scaffold for the regeneration of valvular tissue should also replicate the natural heart valve extracellular matrix (ECM) in terms of biomechanical properties and structural stability. In our previous paper, we demonstrated the development of collagen type I and hyaluronic acid (HA)-based scaffolds with interlaced microstructure. Such hybrid scaffolds were found to be compatible with cardiosphere-derived cells (CDCs) to potentially regenerate the diseased aortic heart valve. This paper focused on the quantification of the effect of crosslinking density on the mechanical properties under dry and wet conditions as well as degradation resistance. Elastic moduli increased with increasing crosslinking densities, in the dry and wet state, for parent networks, whereas those of interlaced scaffolds were higher than either network alone. Compressive and storage moduli ranged from 35 ± 5 to 95 ± 5 kPa and 16 ± 2 kPa to 113 ± 6 kPa, respectively, in the dry state. Storage moduli, in the dry state, matched and exceeded those of human aortic valve leaflets (HAVL). Similarly, degradation resistance increased with increasing the crosslinking densities for collagen-only and HA-only scaffolds. Interlaced scaffolds showed partial degradation in the presence of either collagenase or hyaluronidase as compared to when exposed to both enzymes together. These results agree with our previous findings that interlaced scaffolds were composed of independent collagen and HA networks without crosslinking between them. Thus, collagen/HA interlaced scaffolds have the potential to fill in the niche for designing an ideal tissue engineered heart valve (TEHV).

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