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2.
Sci Total Environ ; 882: 163664, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37088381

RESUMO

Contamination of soil and water systems by per- and polyfluoroalkyl substances (PFAS) due to uncontrolled use of aqueous film-forming foams (AFFFs) at firefighting training sites at civilian and military airports is a universal issue and can lead to significant human health and environmental impacts. Remediation of these sites is often complex but necessary to alleviate the PFAS burden and minimise the risks of exposure by eliminating the hotspot/source from which the PFAS spreads. This study presents a probabilistic cost-benefit analysis (CBA) for evaluating PFAS remediation alternatives, which includes monetisation of both direct costs and benefits as well as externalities. The method is applied for a case study to compare five remediation alternatives for managing PFAS contaminated soil at Stockholm Arlanda Airport in Sweden. The social profitability, or the net present value (NPV), of each remediation alternative was calculated in comparison to two reference alternatives - 'total excavation' of the site (Alt 0) or 'do nothing'. Sensitivity analyses and model scenarios were tested to account for uncertainties, including small or large PFAS spreading and simulating different values for the magnitude of annual avoided cost of inaction (i.e., aggregate benefit) from PFAS remediation. In comparison to total excavation, four of the five studied remediation alternatives resulted in a positive mean NPV. Excavation and stabilization/solidification of the hotspot on-site combined with stabilization using activated carbon for the rest of site (Alt 2) had the highest NPV for both spreading scenarios, i.e., Alt 2 was the most socially profitable alternative. Simulations of the annual avoided cost of inaction enabled estimation of the breakeven point at which a remediation alternative becomes socially profitable (NPV > 0) compared to 'do nothing'. Alt 2 had the lowest breakeven point: 7.5 and 5.75 millions of SEK/year for large and small spreading, respectively.


Assuntos
Fluorocarbonos , Poluentes Químicos da Água , Humanos , Solo , Análise Custo-Benefício , Aeroportos , Meio Ambiente , Poluentes Químicos da Água/análise , Água , Fluorocarbonos/análise
3.
Ecotoxicol Environ Saf ; 228: 113025, 2021 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-34847437

RESUMO

Methane (CH4) is the second most important greenhouse gas after carbon dioxide (CO2) and is inter alia produced in natural freshwater ecosystems. Given the rise in CH4 emissions from natural sources, researchers are investigating environmental factors and climate change feedbacks to explain this increment. Despite being omnipresent in freshwaters, knowledge on the influence of chemical stressors of anthropogenic origin (e.g., antibiotics) on methanogenesis is lacking. To address this knowledge gap, we incubated freshwater sediment under anaerobic conditions with a mixture of five antibiotics at four levels (from 0 to 5000 µg/L) for 42 days. Weekly measurements of CH4 and CO2 in the headspace, as well as their compound-specific δ13C, showed that the CH4 production rate was increased by up to 94% at 5000 µg/L and up to 29% at field-relevant concentrations (i.e., 50 µg/L). Metabarcoding of the archaeal and eubacterial 16S rRNA gene showed that effects of antibiotics on bacterial community level (i.e., species composition) may partially explain the observed differences in CH4 production rates. Despite the complications of transferring experimental CH4 production rates to realistic field conditions, the study indicated that chemical stressors contribute to the emissions of greenhouse gases by affecting the methanogenesis in freshwaters.

4.
J Environ Manage ; 272: 111087, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32669250

RESUMO

Efficient removal techniques are urgently needed to remove organic micropollutants (OMPs) from wastewater, in order to protect water resources. In this study, laccase activity of mushroom substrate colonized by Pleurotus ostreatus was evaluated as a novel wastewater treatment method for removal of OMPs, including diclofenac, bicalutamide, lamotrigine, and metformin at environmentally relevant concentrations. Laccase activity of the colonized mushroom substrate was found to be highest, 0.8 enzyme activity (U)/g mushroom substrate wet weight, immediately before initiation of fruiting body formation. The selected OMPs were treated for 5 min with suspensions of mushroom substrate with laccase activity of approximately 50 U/L. Removal of all OMPs was significant, with the highest removal for diclofenac of 90% compared with a control with uncolonized mushroom substrate. To our knowledge, direct use of colonized mushroom substrate in removing diclofenac from water has not been reported previously. Removal efficiency of bicalutamide, lamotrigine, and metformin was 43%, 73%, and 59%, respectively. This demonstrates potential for using mushroom substrate colonized by P. ostreatus for removal of OMPs from wastewater.


Assuntos
Agaricales , Pleurotus , Lignina , Água
5.
PLoS One ; 15(6): e0234476, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32584848

RESUMO

Soils contaminated with per- and polyfluoroalkyl substances (PFASs) are an important source for impacting drinking water delivery systems and surface water bodies world-wide, posing an urgent risk to human health and environmental quality. However, few treatment techniques have been tested for PFAS-contaminated soil hotspots. This study investigated the possibility of thermal desorption as a possible technique to remediate soils contaminated with multiple PFASs. Two fortified soils (∑9PFAS ≈ 4 mg kg-1) and one field-contaminated soil (∑9PFAS ≈ 0.025 mg kg-1) were subjected to a 75-min thermal treatment at temperatures ranging from 150 to 550°C. Soil concentrations of PFASs showed a significant decrease at 350°C, with the ∑9PFAS concentration decreasing by, on average, 43% and 79% in the fortified and field contaminated soils, respectively. At 450°C, >99% of PFASs were removed from the fortified soils, while at 550°C the fraction removed ranged between 71 and 99% for the field contaminated soil. In the field contaminated soil, PFAS classes with functional groups of sulfonates (PFSAs) and sulfonamides (FOSAs) showed higher removal than the perfluoroalkyl carboxylates (PFCAs). Thus thermal desorption has the potential to remove a wide variety of PFASs from soil, although more studies are needed to investigate the cost-effectiveness, creation of transformation products, and air-phase vacuum filtration techniques.


Assuntos
Alcanossulfonatos , Recuperação e Remediação Ambiental/métodos , Fluorocarbonos , Incineração/métodos , Poluentes do Solo
7.
Sci Total Environ ; 565: 279-286, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27177134

RESUMO

A novel and efficient organic waste management strategy currently gaining great attention is fly larvae composting. High resource recovery efficiency can be achieved in this closed-looped system, but pharmaceuticals and pesticides in waste could potentially accumulate in every loop of the treatment system and spread to the environment. This study evaluated the fate of three pharmaceuticals (carbamazepine, roxithromycin, trimethoprim) and two pesticides (azoxystrobin, propiconazole) in a fly larvae composting system and in a control treatment with no larvae. It was found that the half-life of all five substances was shorter in the fly larvae compost (<10% of control) and no bioaccumulation was detected in the larvae. Fly larvae composting could thus impede the spread of pharmaceuticals and pesticides into the environment.


Assuntos
Biodegradação Ambiental , Compostagem/métodos , Dípteros/metabolismo , Larva/metabolismo , Praguicidas/metabolismo , Preparações Farmacêuticas/metabolismo , Animais , Meia-Vida , Suécia
8.
Phys Rev Lett ; 99(15): 154801, 2007 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-17995173

RESUMO

Acceleration of polarized protons in the energy range of 5 to 25 GeV is challenging. In a medium energy accelerator, the depolarizing spin resonances are strong enough to cause significant polarization loss but full Siberian snakes cause intolerably large orbit excursions and are also not feasible since straight sections usually are too short. Recently, two helical partial Siberian snakes with double pitch design have been installed in the Brookhaven Alternating Gradient Synchrotron (AGS). With a careful setup of optics at injection and along the energy ramp, this combination can eliminate the intrinsic and imperfection depolarizing resonances otherwise encountered during acceleration to maintain a high intensity polarized beam in medium energy synchrotrons. The observation of partial snake resonances of higher than second order will also be described.

9.
Phys Rev Lett ; 96(17): 174801, 2006 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-16712305

RESUMO

The Brookhaven Relativistic Heavy Ion Collider (RHIC) has been providing collisions of polarized protons at a beam energy of 100 GeV since 2001. Equipped with two full Siberian snakes in each ring, polarization is preserved during acceleration from injection to 100 GeV. However, the intrinsic spin resonances beyond 100 GeV are about a factor of 2 stronger than those below 100 GeV making it important to examine the impact of these strong intrinsic spin resonances on polarization survival and the tolerance for vertical orbit distortions. Polarized protons were first accelerated to the record energy of 205 GeV in RHIC with a significant polarization measured at top energy in 2005. This Letter presents the results and discusses the sensitivity of the polarization survival to orbit distortions.

10.
Phys Rev Lett ; 84(6): 1184-7, 2000 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-11017474

RESUMO

A new type of spin depolarization resonance has been observed at the Brookhaven Alternating Gradient Synchrotron (AGS). This spin resonance is identified as a strong closed-orbit sideband around the dominant intrinsic spin resonance. The strength of the resonance was proportional to the 9th harmonic component of the horizontal closed orbit and proportional to the vertical betatron oscillation amplitude. This "hybrid" spin resonance cannot be overcome by the partial snake at the AGS, but it can be corrected by the harmonic orbit correctors.

11.
Health Educ Res ; 14(3): 399-410, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10539230

RESUMO

Motivational interviewing offers health care professionals a potentially effective strategy for increasing a patient's readiness to change health behaviors. Recently, elements of motivational interviewing and the stages of change model have been simplified and adapted for use with patients in brief clinical encounters. This paper describes in detail a brief motivational intervention model to improve and renew dietary adherence with adolescents in the Dietary Intervention Study in Children (DISC). DISC is a randomized, multi-center clinical trial assessing the efficacy and safety of lowering dietary fat to decrease low-density lipoprotein cholesterol in high-risk children. In the first 3 years of follow-up covering ages 8-13, intervention participants (n = 334) were exposed to a family-based group intervention approach to change dietary choices. To address adherence and retention obstacles as participants moved into adolescence (age 13-17), an individual-level motivational intervention was implemented. The DISC motivational intervention integrates several intervention models: stages of change, motivational interviewing, brief negotiation and behavioral self-management. A preliminary test of the intervention model suggests that it was acceptable to the participants, popular with interventionists and appeared to be an age-appropriate shift from a family-based intervention model.


Assuntos
Comportamento do Adolescente , Dieta com Restrição de Gorduras , Comportamentos Relacionados com a Saúde , Educação de Pacientes como Assunto , Adolescente , Feminino , Humanos , Entrevistas como Assunto , Masculino , Motivação , Cooperação do Paciente
13.
Exp Clin Endocrinol ; 81(1): 83-7, 1983 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6682786

RESUMO

One hundred bi- or homosexual men as well as 100 heterosexual men of similar age were asked about maternal stressful events that may have occurred during their prenatal life. A significantly increased incidence of prenatal stress was found in bisexual and, particularly, in homosexual men. This finding suggests that prenatal stress in males may represent a risk factor for the etiogenesis of sexual deviations in later life.


Assuntos
Homossexualidade , Acontecimentos que Mudam a Vida , Efeitos Tardios da Exposição Pré-Natal , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Gravidez não Desejada , Guerra
14.
Endokrinologie ; 75(3): 365-8, 1980 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7428712

RESUMO

Out of 865 homosexual males who were registered by venerologists in 6 districts of the GDR highly significantly more homosexuals were born during the stressful war and early postwar period of the Second World War, i.e. between 1941 and 1947 (with a maximum of relative frequency in 1944-1945), than in the years before or after this critical period. This finding suggests that stressful prenatal (or perinatal) events may represent an aetiogenetic factor for homosexuality in human males.


Assuntos
Homossexualidade , Estresse Psicológico/fisiopatologia , Feminino , Feto/fisiologia , Alemanha Oriental , Humanos , Masculino , Gravidez , Estatística como Assunto , Guerra
15.
Endokrinologie ; 68(1): 115-7, 1976 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1033829

RESUMO

Total and free plasma testosterone (T) were determined in male homosexuals. While total T showed no significant difference to a heterosexual control group, apparently free T in plasma was significantly lower (p less than 0.001) in 35 male homosexuals (mean +/- SD = 10.7 +/- 3.3 ng/100 ml) than in 38 male heterosexuals of similar age (13.3 +/- 4.5 ng/100 ml).


Assuntos
Homossexualidade/sangue , Testosterona/sangue , Adulto , Humanos , Masculino , Globulina de Ligação a Hormônio Sexual/análise
17.
Science ; 167(3914): 87-8, 1970 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-17759500
18.
Talanta ; 15(11): 1073-8, 1968 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18960410

RESUMO

A critical account of Smales's contributions to the accumulation of data important in geochemistry.

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