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1.
Environ Sci Technol ; 57(25): 9342-9352, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37294896

RESUMO

Persistent organic pollutants (POPs) are recognized as pollutants of global concern, but so far, information on the trends of legacy POPs in the waters of the world has been missing due to logistical, analytical, and financial reasons. Passive samplers have emerged as an attractive alternative to active water sampling methods as they accumulate POPs, represent time-weighted average concentrations, and can easily be shipped and deployed. As part of the AQUA-GAPS/MONET, passive samplers were deployed at 40 globally distributed sites between 2016 and 2020, for a total of 21 freshwater and 40 marine deployments. Results from silicone passive samplers showed α-hexachlorocyclohexane (HCH) and γ-HCH displaying the greatest concentrations in the northern latitudes/Arctic Ocean, in stark contrast to the more persistent penta (PeCB)- and hexachlorobenzene (HCB), which approached equilibrium across sampling sites. Geospatial patterns of polychlorinated biphenyl (PCB) aqueous concentrations closely matched original estimates of production and use, implying limited global transport. Positive correlations between log-transformed concentrations of Σ7PCB, ΣDDTs, Σendosulfan, and Σchlordane, but not ΣHCH, and the log of population density (p < 0.05) within 5 and 10 km of the sampling sites also supported limited transport from used sites. These results help to understand the extent of global distribution, and eventually time-trends, of organic pollutants in aquatic systems, such as across freshwaters and oceans. Future deployments will aim to establish time-trends at selected sites while adding to the geographical coverage.


Assuntos
Poluentes Atmosféricos , Poluentes Ambientais , Hidrocarbonetos Clorados , Praguicidas , Bifenilos Policlorados , Bifenilos Policlorados/análise , Monitoramento Ambiental/métodos , Hexaclorobenzeno/análise , Água Doce , Poluentes Atmosféricos/análise , Praguicidas/análise , Hidrocarbonetos Clorados/análise
2.
Glob Chang Biol ; 24(1): e352-e364, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28944532

RESUMO

Phytoplankton primary production is at the base of the marine food web; changes in primary production have direct or indirect effects on higher trophic levels, from zooplankton organisms to marine mammals and seabirds. Here, we present a new time-series on gross primary production in the North Sea, from 1988 to 2013, estimated using in situ measurements of chlorophyll and underwater light. This shows that recent decades have seen a significant decline in primary production in the North Sea. Moreover, primary production differs in magnitude between six hydrodynamic regions within the North Sea. Sea surface warming and reduced riverine nutrient inputs are found to be likely contributors to the declining levels of primary production. In turn, significant correlations are found between observed changes in primary production and the dynamics of higher trophic levels including (small) copepods and a standardized index of fish recruitment, averaged over seven stocks of high commercial significance in the North Sea. Given positive (bottom-up) associations between primary production, zooplankton abundance and fish stock recruitment, this study provides strong evidence that if the decline in primary production continues, knock-on effects upon the productivity of fisheries are to be expected unless these fisheries are managed effectively and cautiously.


Assuntos
Peixes/fisiologia , Cadeia Alimentar , Zooplâncton/fisiologia , Animais , Copépodes , Pesqueiros , Mar do Norte , Fitoplâncton , Dinâmica Populacional
3.
Br J Neurosurg ; 25(2): 231-4, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21344959

RESUMO

BACKGROUND: Spontaneous supratentorial intracerebral haemorrhage (ICH) is a devastating condition with a high morbidity and mortality, and uncertainty remains regarding the role of surgery in many cases. The Surgical Trial in IntraCerebral Haemorrhage II (STICH II) was initiated to look at subjects with superficial lobar ICH, as the initial STICH trial showed the greatest benefit from early surgery in this subgroup. Our aim was to estimate how many patients with ICH referred to the Greater Manchester Neurosciences Centre (GMNC) met the inclusion and exclusion criteria of the STICH II trial. METHODS: The number of patients eligible for STICH II was determined from the GMNC referral database and admissions to the stroke unit over 1 year (2008). Eligibility was determined by predefined criteria, and equipoise was agreed by two consultant neurosurgeons. RESULTS: One hundred and sixty-eight (38.7%) of 434 ICH referrals were lobar ICH; 53 (31.5% of lobar ICH) of these met the radiological and Glasgow Coma Scale (GCS) criteria for STICH II, but only 16 (9.5% of lobar ICH; 3.7% of all ICH) had equipoise agreed on by two neurosurgeons. Thirty-five ICH patients were admitted to the stroke unit, and 12 (34.3%) of these had lobar ICH; none were eligible for STICH II. CONCLUSIONS: The number of patients eligible for recruitment into STICH II is small, necessitating an aggressive recruitment approach. Recruitment should focus on neuroscience centres with neurosurgical units as opposed to stroke units.


Assuntos
Hemorragia Cerebral/cirurgia , Craniotomia/estatística & dados numéricos , Hematoma/cirurgia , Seleção de Pacientes , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Encaminhamento e Consulta/estatística & dados numéricos , Hemorragia Cerebral/epidemiologia , Bases de Dados Factuais , Inglaterra/epidemiologia , Feminino , Escala de Coma de Glasgow , Hematoma/epidemiologia , Humanos , Masculino
4.
Sci Rep ; 9(1): 20153, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31882779

RESUMO

Shelf seas play an important role in the global carbon cycle, absorbing atmospheric carbon dioxide (CO2) and exporting carbon (C) to the open ocean and sediments. The magnitude of these processes is poorly constrained, because observations are typically interpolated over multiple years. Here, we used 298500 observations of CO2 fugacity (fCO2) from a single year (2015), to estimate the net influx of atmospheric CO2 as 26.2 ± 4.7 Tg C yr-1 over the open NW European shelf. CO2 influx from the atmosphere was dominated by influx during winter as a consequence of high winds, despite a smaller, thermally-driven, air-sea fCO2 gradient compared to the larger, biologically-driven summer gradient. In order to understand this climate regulation service, we constructed a carbon-budget supplemented by data from the literature, where the NW European shelf is treated as a box with carbon entering and leaving the box. This budget showed that net C-burial was a small sink of 1.3 ± 3.1 Tg C yr-1, while CO2 efflux from estuaries to the atmosphere, removed the majority of river C-inputs. In contrast, the input from the Baltic Sea likely contributes to net export via the continental shelf pump and advection (34.4 ± 6.0 Tg C yr-1).

5.
Cancer Res ; 78(20): 5723-5728, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30120210

RESUMO

Advocates bring unique and important viewpoints to the cancer research process, ensuring that scientific and medical advances are patient-centered and relevant. In this article, we discuss the benefits of engaging advocates in cancer research and underscore ways in which both the scientific and patient communities can facilitate this mutually beneficial collaboration. We discuss how to establish and nurture successful scientist-advocate relationships throughout the research process. We review opportunities that are available to advocates who want to obtain training in the evaluation of cancer research. We also suggest practical solutions that can strengthen communication between scientists and advocates, such as introducing scientist-advocate interactions at the trainee level. Finally, we highlight the essential role social media can play in disseminating patient-supported cancer research findings to the patient community and in raising awareness of the importance of promoting cancer research. Our perspective offers a model that Georgetown Breast Cancer Advocates have found effective and which could be one option for those interested in developing productive, successful, and sustainable collaborations between advocates and scientists in cancer research. Cancer Res; 78(20); 5723-8. ©2018 AACR.


Assuntos
Neoplasias da Mama/terapia , Oncologia/organização & administração , Modelos Organizacionais , Defesa do Paciente , Relações Profissional-Paciente , Academias e Institutos , Comportamento Cooperativo , Feminino , Hospitais , Humanos , Comunicação Interdisciplinar , Organizações sem Fins Lucrativos , Projetos de Pesquisa/normas , Pesquisadores , Apoio à Pesquisa como Assunto , Estados Unidos
6.
Mar Environ Res ; 55(3): 181-92, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12683438

RESUMO

The standard toxicity test organism, Corophium volutator, exhibits a behavioural response to contaminated sediments that causes increased turbidity of overlying water. We quantify the effects of this response to an estuarine sediment spiked with copper and hydrocarbon contaminated sediments from an oil installation in the North Sea. Turbidity measured 24 h after the start of a toxicity test shows a strong relationship with contaminant concentrations and with mortality after 10 days. Turbidity measurements can therefore give a rapid indication of sediment toxicity, permitting a reduction in storage time of sediments to be used in dilution series and toxicity identification evaluation (TIE) tests, reducing the likelihood of contaminants degrading prior to testing.


Assuntos
Anfípodes , Sedimentos Geológicos/química , Movimento , Poluentes da Água/efeitos adversos , Animais , Bioensaio , Cobre/efeitos adversos , Hidrocarbonetos/efeitos adversos , Tamanho da Partícula , Reprodutibilidade dos Testes , Água/química , Movimentos da Água
7.
PLoS One ; 7(11): e49319, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23166639

RESUMO

Population fluctuations are often driven by an interplay between intrinsic population processes and extrinsic environmental forcing. To investigate this interplay, we analyzed fluctuations in coastal phytoplankton concentration in relation to the tidal cycle. Time series of chlorophyll fluorescence, suspended particulate matter (SPM), salinity and temperature were obtained from an automated measuring platform in the southern North Sea, covering 9 years of data at a resolution of 12 to 30 minutes. Wavelet analysis showed that chlorophyll fluctuations were dominated by periodicities of 6 hours 12 min, 12 hours 25 min, 24 hours and 15 days, which correspond to the typical periodicities of tidal current speeds, the semidiurnal tidal cycle, the day-night cycle, and the spring-neap tidal cycle, respectively. During most of the year, chlorophyll and SPM fluctuated in phase with tidal current speed, indicative of alternating periods of sinking and vertical mixing of algal cells and SPM driven by the tidal cycle. Spring blooms slowly built up over several spring-neap tidal cycles, and subsequently expanded in late spring when a strong decline of the SPM concentration during neap tide enabled a temporary "escape" of the chlorophyll concentration from the tidal mixing regime. Our results demonstrate that the tidal cycle is a major determinant of phytoplankton fluctuations at several different time scales. These findings imply that high-resolution monitoring programs are essential to capture the natural variability of phytoplankton in coastal waters.


Assuntos
Eutrofização/fisiologia , Material Particulado/análise , Fitoplâncton/crescimento & desenvolvimento , Ondas de Maré , Clorofila/metabolismo , Fluorescência , Mar do Norte , Dinâmica Populacional , Fatores de Tempo
8.
Man Ther ; 16(6): 623-8, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21831693

RESUMO

Benign joint hypermobility syndrome (BJHS) is associated with the early development of certain degenerative conditions, which may be associated with altered muscle activity. This pilot study compared muscle activation patterns during postural tasks between people with BJHS who do not have pain and people with normal flexibility (control group). Sixteen subjects aged 22-45 years (8 with BJHS) were selected from a population recruited to a larger study. Electromyographic activity of erector spinae (ES), gluteus medius (GM), and lower limb (rectus femoris (RF), semitendinosus (ST), tibialis anterior (TA) and gastrocnemius lateralis) muscles was assessed, and chosen based on the muscles being tested in the larger study. Subjects carried out 30 s of quiet standing (QS) and one-leg standing (OLS), both with eyes open (EO) and eyes closed (EC). Both groups had significantly more TA activity, and control subjects had significantly more GM activity, during OLS EC compared with QS. GM activity was not significantly different between groups. Compared with the BJHS group, control subjects had significantly less ST activation overall, significantly more ES activity during OLS EC and significantly less RF-ST co-contraction during QS. This study has noted differences in muscle activation patterns between pain-free hypermobile people and control subjects, specifically involving muscles surrounding the pelvis and hip. This pilot data suggests that strategies for stabilising the body during balancing tasks may be relevant to injury risk in people with BJHS. While results need to be verified with a larger subject sample, this study is important in developing new treatments for hypermobile people.


Assuntos
Instabilidade Articular/fisiopatologia , Músculo Esquelético/fisiologia , Equilíbrio Postural/fisiologia , Adolescente , Adulto , Análise de Variância , Estudos de Casos e Controles , Eletromiografia/métodos , Feminino , Humanos , Extremidade Inferior , Masculino , Pessoa de Meia-Idade , Contração Muscular/fisiologia , Pelve , Projetos Piloto , Valores de Referência , Adulto Jovem
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