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1.
Ambio ; 51(9): 1978-1993, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35503201

RESUMO

Blue Carbon Ecosystems (BCEs) help mitigate and adapt to climate change but their integration into policy, such as Nationally Determined Contributions (NDCs), remains underdeveloped. Most BCE conservation requires community engagement, hence community-scale projects must be nested within the implementation of NDCs without compromising livelihoods or social justice. Thirty-three experts, drawn from academia, project development and policy, each developed ten key questions for consideration on how to achieve this. These questions were distilled into ten themes, ranked in order of importance, giving three broad categories of people, policy & finance, and science & technology. Critical considerations for success include the need for genuine participation by communities, inclusive project governance, integration of local work into national policies and practices, sustaining livelihoods and income (for example through the voluntary carbon market and/or national Payment for Ecosystem Services and other types of financial compensation schemes) and simplification of carbon accounting and verification methodologies to lower barriers to entry.


Assuntos
Carbono , Ecossistema , Sequestro de Carbono , Mudança Climática , Conservação dos Recursos Naturais/métodos , Humanos
2.
J Appl Crystallogr ; 54(Pt 5): 1455-1479, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34667451

RESUMO

The precipitation of hydrated phases from a chondrite-like Na-Mg-Ca-SO4-Cl solution is studied using in situ synchrotron X-ray powder diffraction, under rapid- (360 K h-1, T = 250-80 K, t = 3 h) and ultra-slow-freezing (0.3 K day-1, T = 273-245 K, t = 242 days) conditions. The precipitation sequence under slow cooling initially follows the predictions of equilibrium thermodynamics models. However, after ∼50 days at 245 K, the formation of the highly hydrated sulfate phase Na2Mg(SO4)2·16H2O, a relatively recent discovery in the Na2Mg(SO4)2-H2O system, was observed. Rapid freezing, on the other hand, produced an assemblage of multiple phases which formed within a very short timescale (≤4 min, ΔT = 2 K) and, although remaining present throughout, varied in their relative proportions with decreasing temperature. Mirabilite and meridianiite were the major phases, with pentahydrite, epsomite, hydrohalite, gypsum, blödite, konyaite and loweite also observed. Na2Mg(SO4)2·16H2O was again found to be present and increased in proportion relative to other phases as the temperature decreased. The results are discussed in relation to possible implications for life on Europa and application to other icy ocean worlds.

3.
Nat Commun ; 11(1): 4599, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32934227

RESUMO

Accounting guidelines exist for the recording of carbon flows in terrestrial and coastal ecosystems. Shelf sea sediments, while considered an important carbon store, have yet to receive comparable scrutiny. Here, we explore whether effective management of carbon stocks accumulating in shelf seas could contribute towards a nation's greenhouse gas emissions reduction targets. We review the complexities of carbon transport and fate in shelf seas, and the geopolitical challenges of carbon accounting in climate governance because of the transboundary nature of carbon flows in the marine environment. New international accounting guidance and governance frameworks are needed to prompt climate action.

5.
Nat Commun ; 10(1): 3998, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31488846

RESUMO

The term Blue Carbon (BC) was first coined a decade ago to describe the disproportionately large contribution of coastal vegetated ecosystems to global carbon sequestration. The role of BC in climate change mitigation and adaptation has now reached international prominence. To help prioritise future research, we assembled leading experts in the field to agree upon the top-ten pending questions in BC science. Understanding how climate change affects carbon accumulation in mature BC ecosystems and during their restoration was a high priority. Controversial questions included the role of carbonate and macroalgae in BC cycling, and the degree to which greenhouse gases are released following disturbance of BC ecosystems. Scientists seek improved precision of the extent of BC ecosystems; techniques to determine BC provenance; understanding of the factors that influence sequestration in BC ecosystems, with the corresponding value of BC; and the management actions that are effective in enhancing this value. Overall this overview provides a comprehensive road map for the coming decades on future research in BC science.

6.
J Appl Crystallogr ; 51(Pt 4): 1197-1210, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30147638

RESUMO

Liquid oceans and ice caps, along with ice crusts, have long been considered defining features of the Earth, but space missions and observations have shown that they are in fact common features among many of the solar system's outer planets and their satellites. Interactions with rock-forming materials have produced saline oceans not dissimilar in many respects to those on Earth, where mineral precipitation within frozen seawater plays a significant role in both determining global properties and regulating the environment in which a complex ecosystem of extremophiles exists. Since water is considered an essential ingredient for life, the presence of oceans and ice on other solar system bodies is of great astrobiological interest. However, the details surrounding mineral precipitation in freezing environments are still poorly constrained, owing to the difficulties of sampling and ex situ preservation for laboratory analysis, meaning that predictive models have limited empirical underpinnings. To address this, the design and performance characterization of a transmission-geometry sample cell for use in long-duration synchrotron X-ray powder diffraction studies of in situ mineral precipitation from aqueous ice-brine systems are presented. The cell is capable of very slow cooling rates (e.g. 0.3°C per day or less), and its performance is demonstrated with the results from a year-long study of the precipitation of the hydrated magnesium sulfate phase meridianiite (MgSO4·11H2O) from the MgSO4-H2O system. Evidence from the Mars Rover mission suggests that this hydrated phase is widespread on the present-day surface of Mars. However, as well as the predicted hexagonal ice and meridianiite phases, an additional hydrated sulfate phase and a disordered phase are observed.

7.
Sci Rep ; 7(1): 11917, 2017 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-28928433

RESUMO

Seagrass meadows provide numerous ecosystem services and their rapid global loss may reduce human welfare as well as ecological integrity. In common with the other 'blue carbon' habitats (mangroves and tidal marshes) seagrasses are thought to provide coastal defence and encourage sediment stabilisation and surface elevation. A sophisticated understanding of sediment elevation dynamics in mangroves and tidal marshes has been gained by monitoring a wide range of different sites, located in varying hydrogeomorphological conditions over long periods. In contrast, similar evidence for seagrasses is sparse; the present study is a contribution towards filling this gap. Surface elevation change pins were deployed in four locations, Scotland, Kenya, Tanzania and Saudi Arabia, in both seagrass and unvegetated control plots in the low intertidal and shallow subtidal zone. The presence of seagrass had a highly significant, positive impact on surface elevation at all sites. Combined data from the current work and the literature show an average difference of 31 mm per year in elevation rates between vegetated and unvegetated areas, which emphasizes the important contribution of seagrass in facilitating sediment surface elevation and reducing erosion. This paper presents the first multi-site study for sediment surface elevation in seagrasses in different settings and species.


Assuntos
Alismatales/crescimento & desenvolvimento , Organismos Aquáticos/crescimento & desenvolvimento , Sedimentos Geológicos , Quênia , Arábia Saudita , Escócia , Tanzânia
8.
Sci Rep ; 7(1): 2481, 2017 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-28559544

RESUMO

Accurate pH measurements in polar waters and sea ice brines require pH indicator dyes characterized at near-zero and below-zero temperatures and high salinities. We present experimentally determined physical and chemical characteristics of purified meta-Cresol Purple (mCP) pH indicator dye suitable for pH measurements in seawater and conservative seawater-derived brines at salinities (S) between 35 and 100 and temperatures (T) between their freezing point and 298.15 K (25 °C). Within this temperature and salinity range, using purified mCP and a novel thermostated spectrophotometric device, the pH on the total scale (pHT) can be calculated from direct measurements of the absorbance ratio R of the dye in natural samples as[Formula: see text] Based on the mCP characterization in these extended conditions, the temperature and salinity dependence of the molar absorptivity ratios and - [Formula: see text] of purified mCP is described by the following functions: e 1 = -0.004363 + 3.598 × 10-5 T, e 3/e 2 = -0.016224 + 2.42851 × 10-4 T + 5.05663 × 10-5(S - 35), and - [Formula: see text] = -319.8369 + 0.688159 S -0.00018374 S 2 + (10508.724 - 32.9599 S + 0.059082S 2) T-1 + (55.54253 - 0.101639 S) ln T -0.08112151T. This work takes the characterisation of mCP beyond the currently available ranges of 278.15 K ≤ T ≤ 308.15 K and 20 ≤ S ≤ 40 in natural seawater, thereby allowing high quality pHT measurements in polar systems.

9.
Clin Child Psychol Psychiatry ; 22(3): 500-517, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28447471

RESUMO

This article describes the contribution of video interaction guidance (VIG) to the development of infant and parental and VIG practitioners' mental health and well-being. The theoretical core of VIG was depicted in terms of concepts such as intersubjectivity, attunement and mediated learning. The way the VIG principles alongside the underpinning values and beliefs promote a process of attunement between parent and infant, the VIG practitioner and parent, and the VIG practitioner and supervisor is described. This article also describes some of the evidence about the effectiveness of video feedback techniques more generally and the way in which the underpinning theory of change enables VIG to target key ports of entry in terms of areas that have been highlighted by numerous epidemiological studies as being important in terms of supporting or derailing infant attachment security. A case study is used to demonstrate the way in which VIG can be integrated within broader therapeutic approaches such as parent-infant psychotherapy to support the interaction of parents who have been deeply traumatised in childhood. It also demonstrates how the parallel process of practitioner 'attunement' to mother is key to the mother's recovery and her new ability to form attuned relationships herself with her children and other adults.


Assuntos
Saúde Mental , Relações Pais-Filho , Pais/psicologia , Satisfação Pessoal , Adulto , Humanos , Lactente , Apego ao Objeto
10.
Issue Brief (Commonw Fund) ; 1: 1-22, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22351970

RESUMO

The Beacon Community Cooperative Agreement Program is funding 17 communities to build and strengthen their health information technology (IT) capabilities to enhance care coordination, improve patient and population health, and reduce or restrain costs. Based on the experiences and evidence generated by these communities, the program hopes to illustrate the possibilities of leveraging health IT to achieve desired goals. Doing so requires rigorous evaluation work, which is the subject of this issue brief. Based on semistructured interviews with representatives from each Beacon Community, the brief outlines various study designs, evaluation approaches, outcome measures, and data sources in use. It also identifies some common challenges, including establishing governance models, determining baseline measures, and assessing impact in a relatively constrained timeframe. Technical assistance in disseminating and publishing findings and assessing return on investments will be offered in the coming year.


Assuntos
Serviços de Saúde Comunitária/organização & administração , Estudos de Avaliação como Assunto , Programas Governamentais/organização & administração , Informática Médica/organização & administração , Projetos de Pesquisa , Organizações de Assistência Responsáveis , American Recovery and Reinvestment Act , Doença Crônica , Controle de Custos , Análise Custo-Benefício , Disparidades em Assistência à Saúde , Humanos , Avaliação de Processos e Resultados em Cuidados de Saúde , Qualidade da Assistência à Saúde , Estados Unidos
11.
Rapid Commun Mass Spectrom ; 19(8): 1063-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15776498

RESUMO

We investigated the effects of sample acidification on the stable carbon and nitrogen isotopic composition (delta13C and delta15N), as well as the organic carbon (OC) and total nitrogen (TN) composition, of an algal culture and a marine sediment. Replicate measurements of untreated and acid-treated samples were made using 1 M, 2 M and 6 M HCl, 6% H2SO3 and 1 M H3PO4. For all treatments the precision of the analysis for the acid-treated sample was equal to or less than that in the non-acidified sample. For the algae, analysis of variance (ANOVA) indicated no significant differences in the mean OC and TN concentration, or delta13C and delta15N composition, between any acid treatment and non-acidified samples. For the sediment sample a comparison could only be made between the different acid treatments because the untreated contained significant amounts ( approximately 30%) of carbonate carbon. ANOVA indicated that the mean OC determined in sediment samples after the 1 M HCl treatment and the mean delta13C values after the 6% H2SO3 and 1 M H3PO4 treatments were significantly different (p < 0.013 and < .05, respectively) from all other treatments. Mass balance calculations indicate that in some instances delta13C values were biased due to a contribution from unreacted carbonate carbon. There were no significant differences in the mean TN between any acid-treated and non-acidified samples. The mean delta15N values after 6 M HCl, 6% H2SO3 and 1 M H3PO4 treatments were significantly different from the untreated sediment sample (p < 0.044). Based on the significant bias observed for the delta15N and delta13C values, a weak (1-2 M) HCl solution is confirmed as the most appropriate acid for the removal of inorganic carbon from natural materials requiring elemental and isotopic analysis.


Assuntos
Isótopos de Carbono/análise , Carbono/análise , Eucariotos/química , Sedimentos Geológicos/química , Isótopos de Nitrogênio/análise , Nitrogênio/análise , Concentração de Íons de Hidrogênio , Reprodutibilidade dos Testes
12.
Rapid Commun Mass Spectrom ; 17(11): 1099-106, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12772264

RESUMO

The conversion of ammonium (NH(4) (+)) to 1-sulfonato-iso-indole has been examined as a method for natural abundance measurement of delta(15)N of NH(4) (+). The reaction is complete within 2 h and is based on the derivatisation of NH(4) (+) by o-phthaldialdehyde and sodium sulfite at a high pH, 11.2. The product is readily concentrated from dilute solutions by reverse-phase solid-phase extraction (SPE). The method is compound-specific despite partial derivatisation of potentially interfering amino acids, as their derivatives are not extracted by SPE. delta(15)N values of NH(4) (+) in KCL soil extracts can be measured within 48 h by automated continuous-flow IRMS with a precision of 0.23 per thousand (1 SD). Parallel measurements of NH(4) (+) standards of known delta(15)N are made to allow correction for the isotopic dilution by non-sample NH(4) (+). The practicality of this method is demonstrated by measuring the changes in NH(4) (+) concentration and delta(15)N following the addition of urea as a nitrogen source to inorganic N-depleted soil.


Assuntos
Indóis/análise , Indóis/química , Compostos de Amônio Quaternário/análise , Compostos de Amônio Quaternário/química , Aminoácidos/análise , Isótopos de Nitrogênio , Concentração Osmolar , Compostos de Amônio Quaternário/isolamento & purificação , Sensibilidade e Especificidade , Ureia/química
13.
Infect Immun ; 70(11): 6114-20, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12379688

RESUMO

WC1(+) gammadelta T cells of Mycobacterium bovis-infected cattle are highly responsive to M. bovis sonic extract (MBSE). In mycobacterial infections of other species, gammadelta T cells have been shown to respond to protein and nonprotein antigens, but the bovine WC1(+) gammadelta T-cell antigenic targets within MBSE require further definition in terms of the dominance of protein versus nonprotein components. The present study sought to characterize the WC1(+) gammadelta T-cell antigenic targets, together with the role of interleukin-2 (IL-2), in the context of M. bovis infection. This was achieved by testing crude and defined antigens to assess protein versus nonprotein recognition by WC1(+) gammadelta T cells in comparison with CD4(+) alphabeta T cells. Both cell types proliferated strongly in response to MBSE, with CD4(+) T cells being the major producers of gamma interferon (IFN-gamma). However, enzymatic digestion of the protein in MBSE removed its ability to stimulate CD4(+) T-cell responses, whereas some WC1(+) gammadelta T-cell proliferation remained. The most antigenic protein inducing proliferation and IFN-gamma secretion in WC1(+) gammadelta T-cell cultures was found to be ESAT-6, which is a potential novel diagnostic reagent and vaccine candidate. In addition, WC1(+) gammadelta T-cell proliferation was observed in response to stimulation with prenyl pyrophosphate antigens (isopentenyl pyrophosphate and monomethyl phosphate). High levels of cellular activation (CD25 expression) resulted from MBSE stimulation of WC1(+) gammadelta T cells from infected animals. A similar degree of activation was induced by IL-2 alone, but for WC1(+) gammadelta T-cell division IL-2 was found to act only as a costimulatory signal, enhancing antigen-driven responses. Overall, the data indicate that protein antigens are important stimulators of WC1(+) gammadelta T-cell proliferation and IFN-gamma secretion in M. bovis infection, with nonprotein antigens inducing significant proliferation. These findings have important implications for diagnostic and vaccine development.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Glicoproteínas de Membrana/análise , Mycobacterium bovis/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/análise , Subpopulações de Linfócitos T/imunologia , Animais , Bovinos , Interferon gama/biossíntese , Interleucina-2/farmacologia , Ativação Linfocitária , Masculino , Receptores de Interleucina-2/análise
14.
Infect Immun ; 70(3): 1488-500, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11854237

RESUMO

It is accepted that cell-mediated immune responses predominate in mycobacterial infections. Many studies have shown that CD4(+) T cells produce Th1 cytokines, such as gamma interferon (IFN-gamma), in response to mycobacterial antigens and that the cytolytic activity of CD8(+) cells toward infected macrophages is important. However, the extent and manner in which gamma delta T cells participate in this response remain unclear. In ruminants, gamma delta T cells comprise a major proportion of the peripheral blood mononuclear cell population. We have previously shown that WC1(+) gamma delta T cells are involved early in Mycobacterium bovis infection of cattle, but their specific functions are not well understood. Here we describe an in vivo model of bovine tuberculosis in which the WC1(+) gamma delta T cells were depleted from the peripheral circulation and respiratory tract, by infusion of WC1(+)-specific monoclonal antibody, prior to infection. While no effects on disease pathology were observed in this experiment, results indicate that WC1(+) gamma delta T cells, which become significantly activated (CD25(+)) in the circulation of control calves from 21 days postinfection, may play a role in modulating the developing immune response to M. bovis. WC1(+)-depleted animals exhibited decreased antigen-specific lymphocyte proliferative response, an increased antigen-specific production of interleukin-4, and a lack of specific immunoglobulin G2 antibody. This suggests that WC1(+) gamma delta TCR(+) cells contribute, either directly or indirectly, toward the Th1 bias of the immune response in bovine tuberculosis--a hypothesis supported by the decreased innate production of IFN-gamma, which was observed in WC1(+)-depleted calves.


Assuntos
Glicoproteínas de Membrana/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Linfócitos T/imunologia , Tuberculose Bovina/imunologia , Animais , Anticorpos Antibacterianos/sangue , Bovinos , Imunoglobulina G/sangue , Interferon gama/metabolismo , Interleucina-2/metabolismo , Interleucina-4/metabolismo , Depleção Linfocítica , Masculino , Subpopulações de Linfócitos T , Células Th1/imunologia
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