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1.
Sci Total Environ ; 915: 169881, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38190895

RESUMO

The hydrological restoration of coastal wetlands is an emerging approach for mitigating and adapting to climate change and enhancing ecosystem services such as improved water quality and biodiversity. This paper synthesises current knowledge on selecting appropriate modelling approaches for hydrological restoration projects. The selection of a modelling approach is based on project-specific factors, such as costs, risks, and uncertainties, and aligns with the overall project objectives. We provide guidance on model selection, emphasising the use of simpler and less expensive modelling approaches when appropriate, and identifying situations when models may not be required for project managers to make informed decisions. This paper recognises and supports the widespread use of hydrological restoration in coastal wetlands by bridging the gap between hydrological science and restoration practices. It underscores the significance of project objectives, budget, and available data and offers decision-making frameworks, such as decision trees, to aid in matching modelling methods with specific project outcomes.

2.
Sci Data ; 9(1): 744, 2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36460674

RESUMO

The Chesapeake Bay is a region along the eastern coast of the United States where sea-level rise is confounded with poorly resolved rates of land subsidence, thus new constraints on vertical land motions (VLM) in the region are warranted. In this paper, we provide a description of two campaign-style Global Positioning System (GPS) datasets, explain the methods used in data collection and validation, and present the experiment designed to quantify a new baseline of VLM in the Chesapeake Bay region of eastern North America. Data from GPS campaigns in 2019 and 2020 are presented as ASCII RINEX2.11 files and logsheets for each observation from the campaigns. Data were quality checked using the open-source program TEQC, resulting in average multipath 1 and 2 values of 0.68 and 0.57, respectively. All data are archived and publicly available for open access at the geodesy facility UNAVCO to abide by Findable, Accessible, Interoperable, Reusable (FAIR) data principles.

3.
Sci Rep ; 12(1): 17636, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36271232

RESUMO

"Blue carbon" wetland vegetation has a limited freshwater requirement. One type, mangroves, utilizes less freshwater during transpiration than adjacent terrestrial ecoregions, equating to only 43% (average) to 57% (potential) of evapotranspiration ([Formula: see text]). Here, we demonstrate that comparative consumptive water use by mangrove vegetation is as much as 2905 kL H2O ha-1 year-1 less than adjacent ecoregions with [Formula: see text]-to-[Formula: see text] ratios of 47-70%. Lower porewater salinity would, however, increase mangrove [Formula: see text]-to-[Formula: see text] ratios by affecting leaf-, tree-, and stand-level eco-physiological controls on transpiration. Restricted water use is also additive to other ecosystem services provided by mangroves, such as high carbon sequestration, coastal protection and support of biodiversity within estuarine and marine environments. Low freshwater demand enables mangroves to sustain ecological values of connected estuarine ecosystems with future reductions in freshwater while not competing with the freshwater needs of humans. Conservative water use may also be a characteristic of other emergent blue carbon wetlands.


Assuntos
Carbono , Ecossistema , Humanos , Sequestro de Carbono , Áreas Alagadas , Água Doce , Água
4.
Bioscience ; 69(3): 180-190, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30899122

RESUMO

As humanity continues to grow in size, questions related to human rights and the existing unequal distribution of food resources have taken on greater urgency. Is inequality in food access unjust or a regrettable consequence of the geographic distribution of biophysical resources? To what extent are there obligations to redress inequalities in access to food? We draw from a human rights perspective to identify obligations associated with access to food and develop a quantitative framework to evaluate the fulfillment of the human right to food. We discuss the capacity of socioeconomic development to reduce inequalities in per capita food availability with respect to the distribution of biophysical resources among countries. Although, at the country level, international trade shows the capacity to reduce human rights deficits by increasing food availability in countries with limited food production, whether it actually improves the fulfillment of the right to food will depend on within-country inequality.

5.
Environ Res Lett ; 12(2)2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32818038

RESUMO

Ensuring food security requires food production and distribution systems function throughout disruptions. Understanding the factors that contribute to the global food system's ability to respond and adapt to such disruptions (i.e. resilience) is critical for understanding the long-term sustainability of human populations. Variable impacts of production shocks on food supply between countries indicate a need for national-scale resilience indicators that can provide global comparisons. However, methods for tracking changes in resilience have had limited application to food systems. We developed an indicator-based analysis of food systems resilience for the years 1992-2011. Our approach is based on three dimensions of resilience: socio-economic access to food in terms of income of the poorest quintile relative to food prices, biophysical capacity to intensify or extensify food production, and the magnitude and diversity of current domestic food production. The socio-economic indicator has large variability, but with low values concentrated in Africa and Asia. The biophysical capacity indicator is highest in Africa and Eastern Europe, in part because of high potential for extensification of cropland and for yield gap closure in cultivated areas. However, the biophysical capacity indicator has declined globally in recent years. The production diversity indicator has increased slightly, with a relatively even geographic distribution. Few countries had exclusively high or low values for all indicators. Collectively, these results are the basis for global comparisons of resilience between nations, and provide necessary context for developing generalizations about the resilience in the global food system.

6.
PLoS One ; 11(11): e0165941, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27832118

RESUMO

The easy access to large data sets has allowed for leveraging methodology in network physics and complexity science to disentangle patterns and processes directly from the data, leading to key insights in the behavior of systems. Here we use country specific food production data to study binary and weighted topological properties of the bipartite country-food production matrix. This country-food production matrix can be: 1) transformed into overlap matrices which embed information regarding shared production of products among countries, and or shared countries for individual products, 2) identify subsets of countries which produce similar commodities or subsets of commodities shared by a given country allowing for visualization of correlations in large networks, and 3) used to rank country fitness (the ability to produce a diverse array of products weighted on the type of food commodities) and food specialization (quantified on the number of countries producing a specific food product weighted on their fitness). Our results show that, on average, countries with high fitness produce both low and high specializion food commodities, whereas nations with low fitness tend to produce a small basket of diverse food products, typically comprised of low specializion food commodities.


Assuntos
Mineração de Dados/métodos , Tecnologia de Alimentos , Comércio , Alimentos , Tecnologia de Alimentos/economia , Tecnologia de Alimentos/métodos , Tecnologia de Alimentos/estatística & dados numéricos , Humanos , Internacionalidade
7.
Proc Natl Acad Sci U S A ; 112(22): 6902-7, 2015 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-25964361

RESUMO

The escalating food demand by a growing and increasingly affluent global population is placing unprecedented pressure on the limited land and water resources of the planet, underpinning concerns over global food security and its sensitivity to shocks arising from environmental fluctuations, trade policies, and market volatility. Here, we use country-specific demographic records along with food production and trade data for the past 25 y to evaluate the stability and reactivity of the relationship between population dynamics and food availability. We develop a framework for the assessment of the resilience and the reactivity of the coupled population-food system and suggest that over the past two decades both its sensitivity to external perturbations and susceptibility to instability have increased.


Assuntos
Comércio/métodos , Abastecimento de Alimentos/métodos , Modelos Econômicos , Dinâmica Populacional , Comércio/tendências , Demografia , Humanos
8.
ACS Appl Mater Interfaces ; 6(6): 3987-94, 2014 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-24593226

RESUMO

Poly(vinylidene fluoride-co-tetrafluoroethylene) (PVDF-TFE) is confined between alternating layers of poly(ethylene terephthalate) (PET) utilizing a unique multilayer processing technology, in which PVDF-TFE and PET are melt-processed in a continuous fashion. Postprocessing techniques including biaxial orientation and melt recrystallization were used to tune the crystal orientation of the PVDF-TFE layers, as well as achieve crystallinity in the PET layers through strain-induced crystallization and thermal annealing during the melt recrystallization step. A volume additive model was used to extract the effect of crystal orientation within the PVDF-TFE layers and revealed a significant enhancement in the modulus from 730 MPa in the as-extruded state (isotropic) to 840 MPa in the biaxially oriented state (on-edge) to 2230 MPa in the melt-recrystallized state (in-plane). Subsequently, in situ wide-angle X-ray scattering was used to observe the crystal structure evolution during uniaxial deformation in both the as-extruded and melt-recrystallized states. It is observed that the low-temperature ferroelectric PVDF-TFE crystal phase in the as-extruded state exhibits equatorial sharpening of the 110 and 200 crystal peaks during deformation, quantified using the Hermans orientation function, while in the melt-recrystallized state, an overall increase in the crystallinity occurs during deformation. Thus, we correlated the mechanical response (strain hardening) of the films to these respective evolved crystal structures and highlighted the ability to tailor mechanical response. With a better understanding of the structural evolution during deformation, it is possible to more fully characterize the structural response to handling during use of the high-barrier PVDF-TFE/PET multilayer films as commercial dielectrics and packaging materials.

9.
PLoS One ; 8(2): e55825, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23457481

RESUMO

The global trade of goods is associated with a virtual transfer of the water required for their production. The way changes in trade affect the virtual redistribution of freshwater resources has been recently documented through the analysis of the virtual water network. It is, however, unclear how these changes are contributed by different types of products and regions of the world. Here we show how the global patterns of virtual water transport are contributed by the trade of different commodity types, including plant, animal, luxury (e.g., coffee, tea, and alcohol), and other products. Major contributors to the virtual water network exhibit different trade patterns with regard to these commodity types. The net importers rely on the supply of virtual water from a small percentage of the global population. However, discrepancies exist among the different commodity networks. While the total virtual water flux through the network has increased between 1986 and 2010, the proportions associated with the four commodity groups have remained relatively stable. However, some of the major players have shown significant changes in the virtual water imports and exports associated with those commodity groups. For instance, China has switched from being a net exporter of virtual water associated with other products (non-edible plant and animal products typically used for manufacturing) to being the largest importer, accounting for 31% of the total water virtually transported with these products. Conversely, in the case of The United states of America, the commodity proportions have remained overall unchanged throughout the study period: the virtual water exports from The United States of America are dominated by plant products, whereas the imports are comprised mainly of animal and luxury products.


Assuntos
Comércio/métodos , Internacionalidade , Abastecimento de Água/economia , China , Comércio/economia , Comércio/história , História do Século XX , História do Século XXI , Internacionalidade/história , Internet , Modelos Econômicos , Estados Unidos , Abastecimento de Água/análise , Abastecimento de Água/história
10.
J Am Osteopath Assoc ; 106(11): 647-52, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17192451

RESUMO

Untreated trichophagia secondary to trichotillomania is a potentially life-threatening condition. Taking a thorough family and social history, most notably with the aid of a genogram or family tree, can aid in including this disorder in the differential diagnosis. This case presentation describes a unique occurrence of untreated trichotillomania in a female adolescent that led to formation of a trichobezoar requiring emergent surgical intervention and follow-up psychiatric treatment. This case highlights osteopathic medicine's fundamental concept of treating the whole person rather than just symptoms by considering factors such as genetic influences in understanding disease.


Assuntos
Bezoares/etiologia , Tricotilomania/complicações , Adolescente , Bezoares/cirurgia , Feminino , Humanos , Medicina Osteopática , Tricotilomania/psicologia
11.
Psychosomatics ; 46(4): 362-6, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16000680

RESUMO

Trichophagia secondary to trichotillomania can be a potentially life-threatening condition if left untreated. This report documents the unique case of a 16-year-old girl whose untreated trichotillomania led to a trichobezoar requiring surgical intervention and follow-up psychiatric treatment. Challenges in the identification and treatment of the disorder and its complications are discussed as well as the importance of early and accurate diagnosis.


Assuntos
Bezoares/complicações , Bezoares/cirurgia , Serviços Médicos de Emergência , Tricotilomania/complicações , Adolescente , Feminino , Humanos
12.
Suicide Life Threat Behav ; 34(3): 233-41, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15385178

RESUMO

The military has a well-defined population with suicide prevention programs that have been recognized as possible models for civilian suicide prevention efforts. Monitoring prevention programs requires accurate reporting. In civilian settings, several studies have confirmed problems in the reporting and classification of suicides. This analysis evaluated whether suicides were underreported or misclassified under accident or undetermined manner of death in the military system. We reviewed all 1998 and 1999 military deaths using official death reports and compared these data with additional sources, most importantly the DoD Medical Mortality Registry. We assessed for evidence of expressed suicidal intent and past psychiatric history among deaths classified as undetermined and accidents due to gunshot, overdose, drowning, falls, or asphyxia. Using sources other than official records, we found 17% more suicides than were reported, and an additional 4% of deaths that were suspicious for suicide. This study suggests that reporting and classification errors may account for 21% additional suicides in the military. These findings are comparable to rates seen in civilian studies and add to the literature regarding the problems inherent in using administrative death classification data for medical surveillance purposes.


Assuntos
Computação Matemática , Militares/estatística & dados numéricos , Prevenção do Suicídio , Suicídio/estatística & dados numéricos , Adulto , Feminino , Humanos , Masculino , Estudos Retrospectivos , Estados Unidos/epidemiologia
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