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1.
iScience ; 24(8): 102840, 2021 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-34368656

RESUMEN

Maintaining connectivity between high-elevation public lands is important for wolverines and other species of conservation concern. This work represents the first effort to prioritize wolverine connectivity under future climate conditions using a systematic conservation planning framework. We optimized 10, 15, 20, and 50% of habitat features for wolverines using integer linear programming. We identified 369 privately owned areas in the 10% solution, 572 in the 15% solution, 822 in the 20% solution, and 3,996 in the 50% solution where voluntary landowner easements would improve the long-term landscape functionality for wolverine connectivity. The median estimated easements ranged from $8,762 to $12,220 across the four solutions (total costs $14,874,371 to $196,346,714). Overall, this effort demonstrates the utility of optimization problems for conserving connectivity, provides a proactive tool to engage potential collaborators, identifies easements that will likely protect various subalpine species, and offers a framework for the conservation of additional species.

2.
Ecol Appl ; 31(6): e02387, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34137106

RESUMEN

Connecting protected areas remains an important global conservation strategy in the face of ongoing and future threats to biodiversity. Amid our growing understanding of how species' distributions will respond to climate change, conservation scientists need to plan for connectivity conservation across entire continents. We modeled multiscale connectivity priorities based on the least human-modified lands between large protected areas of North America using least-cost and circuit theory approaches. We first identified priority corridors between large protected areas, then characterized the network's structure to unveil priority linkages most important for maintaining network- and regional-level connectivity. Agreement between least-cost corridors and current flow varied throughout North America, reflecting permeable landscape conditions and "pinch points" where potential ecological flows may concentrate between protected areas. Priority network-level linkages derived from each approach were similar throughout the continental network (e.g., Rocky Mountains and Canadian boreal), but critical linkages that bridged regional protected-area networks varied. We emphasize the importance of planning for connectivity at continental scales and demonstrate the utility of multiple methods when mapping connectivity priorities across large spatial extents with wide gradients in landscape conditions.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Biodiversidad , Canadá , Humanos , América del Norte
3.
Nat Ecol Evol ; 4(10): 1377-1384, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32778752

RESUMEN

Tropical forests vary in composition, structure and function such that not all forests have similar ecological value. This variability is caused by natural and anthropogenic disturbance regimes, which influence the ability of forests to support biodiversity, store carbon, mediate water yield and facilitate human well-being. While international environmental agreements mandate protecting and restoring forests, only forest extent is typically considered, while forest quality is ignored. Consequently, the locations and loss rates of forests of high ecological value are unknown and coordinated strategies for conserving these forests remain undeveloped. Here, we map locations high in forest structural integrity as a measure of ecological quality on the basis of recently developed fine-resolution maps of three-dimensional forest structure, integrated with human pressure across the global moist tropics. Our analyses reveal that tall forests with closed canopies and low human pressure typical of natural conditions comprise half of the global humid or moist tropical forest estate, largely limited to the Amazon and Congo basins. Most of these forests have no formal protection and, given recent rates of loss, are at substantial risk. With the rapid disappearance of these 'best of the last' forests at stake, we provide a policy-driven framework for their conservation and restoration, and recommend locations to maintain protections, add new protections, mitigate deleterious human impacts and restore forest structure.


Asunto(s)
Conservación de los Recursos Naturales , Bosques , Biodiversidad , Humanos , Políticas
4.
Front Public Health ; 8: 289, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32850568

RESUMEN

In the 50 years since the expansion of the legal definition of charity for tax-exempt hospitals, there have been periodic regulatory actions at the municipal, state, and federal level to quantify charitable contributions and justify the deferral of tax revenues. The movement toward risk-based reimbursement in the last decade creates an incentive for a shift in hospital leadership understanding and approach to community benefit programs and services. The historical interpretation of community benefit as an issue of compliance with legal obligations is being questioned by forward-thinking hospital leaders, in recognition that more strategic resource allocation offers the potential to reduce financial risk associated with preventable emergency department and inpatient utilization. Recent actions in the policy arena to strengthen community benefit practices, as well as policies in related areas such as homelessness and behavioral health, challenge hospitals to strengthen their focus on prevention. At the same time, increased availability of data on health care costs, mapping of health care utilization patterns, and parallel overlays of hospital location, jurisdictional boundaries, and the social determinants of health offer significant potential for informed public dialogue at the regional level that builds an ethic of shared ownership for health across sectors. Local public health agencies can play an important role by establishing baselines, goals, and objectives in communities where health inequities are concentrated within county and municipal jurisdictional boundaries to align and focus the assets of health, community development, and business sector stakeholders.


Asunto(s)
Organizaciones de Beneficencia , Exención de Impuesto , Servicios de Salud Comunitaria , Humanos , Políticas , Salud Pública
5.
Sci Data ; 6(1): 232, 2019 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-31653863

RESUMEN

Remotely sensed maps of global forest extent are widely used for conservation assessment and planning. Yet, there is increasing recognition that these efforts must now include elements of forest quality for biodiversity and ecosystem services. Such data are not yet available globally. Here we introduce two data products, the Forest Structural Condition Index (SCI) and the Forest Structural Integrity Index (FSII), to meet this need for the humid tropics. The SCI integrates canopy height, tree cover, and time since disturbance to distinguish short, open-canopy, or recently deforested stands from tall, closed-canopy, older stands typical of primary forest. The SCI was validated against estimates of foliage height diversity derived from airborne lidar. The FSII overlays a global index of human pressure on SCI to identify structurally complex forests with low human pressure, likely the most valuable for maintaining biodiversity and ecosystem services. These products represent an important step in maturation from conservation focus on forest extent to forest stands that should be considered "best of the last" in international policy settings.


Asunto(s)
Biodiversidad , Bosques , Clima Tropical , Conservación de los Recursos Naturales , Tecnología de Sensores Remotos
6.
Prev Chronic Dis ; 15: E108, 2018 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-30171678

RESUMEN

INTRODUCTION: The prevalence of food insecurity and chronic health conditions among older adults is a public health concern. However, little is known about associated health care costs. We estimated the incremental health care costs of food insecurity and selected chronic health conditions among older adults, defined as adults aged 50 or older. METHODS: We analyzed 4 years of data (2011-2014) from the National Health Interview Survey and 3 years of data (2013-2015) from the Medical Expenditure Panel Survey; we used 2-part models to estimate the incremental health care costs associated with food insecurity and 9 chronic conditions (hypertension, coronary heart disease, stroke, emphysema, asthma, cancer, chronic bronchitis, arthritis, and diabetes) among older adults. RESULTS: Approximately 14% of older adult respondents (n = 2,150) reported being food insecure. The 3 most common chronic conditions were the same for both food-insecure and food-secure older adults: hypertension, arthritis, and diabetes. The adjusted annual incremental health care costs resulting from food insecurity among older adults were higher in the presence of hypertension, stroke, and arthritis (P ≤ .05) and in the presence of diabetes (P ≤ .10). These findings were also true for the incremental health care costs resulting from food insecurity in the absence of these specific chronic conditions. CONCLUSION: Our findings show that food insecurity interacts with chronic conditions. We observed higher health care costs in the presence of this interaction for those who were food insecure and had poor health than for those who were food secure.


Asunto(s)
Enfermedad Crónica/economía , Abastecimiento de Alimentos , Costos de la Atención en Salud/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Enfermedad Crónica/epidemiología , Estudios Transversales , Femenino , Estado de Salud , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad
7.
Prev Chronic Dis ; 14: E113, 2017 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-29144894

RESUMEN

INTRODUCTION: More than 42 million people in the United States are food insecure. Although some health care entities are addressing food insecurity among patients because of associations with disease risk and management, little is known about the components of these initiatives. METHODS: The Systematic Screening and Assessment Method was used to conduct a landscape assessment of US health care entity-based programs that screen patients for food insecurity and connect them with food resources. A network of food insecurity researchers, experts, and practitioners identified 57 programs, 22 of which met the inclusion criteria of being health care entities that 1) screen patients for food insecurity, 2) link patients to food resources, and 3) target patients including adults aged 50 years or older (a focus of this assessment). Data on key features of each program were abstracted from documentation and telephone interviews. RESULTS: Most programs (n = 13) focus on patients with chronic disease, and most (n = 12) partner with food banks. Common interventions include referrals to or a list of food resources (n = 19), case managers who navigate patients to resources (n = 15), assistance with federal benefit applications (n = 14), patient education and skill building (n = 13), and distribution of fruit and vegetable vouchers redeemable at farmers markets (n = 8). Most programs (n = 14) routinely screen all patients. CONCLUSION: The programs reviewed use various strategies to screen patients, including older adults, for food insecurity and to connect them to food resources. Research is needed on program effectiveness in improving patient outcomes. Such evidence can be used to inform the investments of potential stakeholders, including health care entities, community organizations, and insurers.


Asunto(s)
Asistencia Alimentaria/organización & administración , Abastecimiento de Alimentos , Recolección de Datos , Asistencia Alimentaria/economía , Humanos , Evaluación de Necesidades , Pobreza , Factores de Riesgo , Estados Unidos
8.
Faraday Discuss ; 202: 247-267, 2017 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-28678237

RESUMEN

Catalytic strategies for the synthesis of 1,5-pentanediol (PDO) with 69% yield from hemicellulose and the synthesis of 1,6-hexanediol (HDO) with 28% yield from cellulose are presented. Fractionation of lignocellulosic biomass (white birch wood chips) in gamma-valerolactone (GVL)/H2O generates a pure cellulose solid and a liquid stream containing hemicellulose and lignin, which is further dehydrated to furfural with 85% yield. Furfural is converted to PDO with sequential dehydration, hydration, ring-opening tautomerization, and hydrogenation reactions. Acid-catalyzed cellulose dehydration in tetrahydrofuran (THF)/H2O produces a mixture of levoglucosenone (LGO) and 5-hydroxymethylfurfural (HMF), which are converted with hydrogen to tetrahydrofuran-dimethanol (THFDM). HDO is then obtained from hydrogenolysis of THFDM. Techno-economic analysis demonstrates that this approach can produce HDO and PDO at a minimum selling price of $4090 per ton.


Asunto(s)
Glicoles/síntesis química , Lignina/química , Pentanos/síntesis química , Biomasa , Catálisis , Deshidratación , Glicoles/química , Concentración de Iones de Hidrógeno , Pentanos/química
9.
ChemSusChem ; 10(7): 1351-1355, 2017 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-28277620

RESUMEN

A process for the synthesis of 1,5-pentanediol (1,5-PD) with 84 % yield from furfural is developed, utilizing dehydration/hydration, ring-opening tautomerization, and hydrogenation reactions. Although this process has more reaction steps than the traditional direct hydrogenolysis of tetrahydrofurfuryl alcohol (THFA), techno-economic analyses demonstrate that this process is the economically preferred route for the synthesis of biorenewable 1,5-PD. 2-Hydroxytetrahydropyran (2-HY-THP) is the key reaction pathway intermediate that allows for a decrease in the minimum selling price of 1,5-PD. The reactivity of 2-HY-THP is 80 times greater than that of THFA over a bimetallic hydrogenolysis catalyst. This enhanced reactivity is a result of the ring-opening tautomerization to 5-hydoxyvaleraldehyde and subsequent hydrogenation to 1,5-PD.


Asunto(s)
Biomasa , Furaldehído/química , Glicoles/química , Pentanos/química , Hidrogenación , Isomerismo
10.
Adv Mater ; 26(5): 746-51, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24293271

RESUMEN

Exceptionally high hydrogen permselectivity, exceeding that of any polymeric or porous inorganic systems, is achieved using an ionically crosslinked multilayer polymer thin film.

11.
J Surg Res ; 106(2): 292-8, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12175981

RESUMEN

BACKGROUND: Vitamin E succinate (VES) is a promising anti-cancer micronutrient. In this study, we tested the hypothesis that VES will promote colon cancer tumor dormancy and inhibit liver metastases in colon cancer. METHODS: CT-26 colon cancer cells were treated with VES in vitro and in an in vivo model of liver metastases. The impact of VES on cellular proliferation and apoptosis was measured in vitro by MTS assay and sandwich ELISA and in vivo by PCNA staining and TUNEL assay, respectively. Correlation coefficients and independent t tests were used for statistical analysis. RESULTS: VES significantly and specifically inhibited cell proliferation (P = 0.011) and promoted apoptosis (P < 0.0074) of cancer cells in vitro. VES produced a 40% reduction of liver metastases (P = 0.037). Five of the eight mice had an excellent response to VES. Subsequent analysis of these five mice revealed a 75% reduction in the number of liver metastases (P < 0.05). VES significantly promoted tumor cell apoptosis (P < 0.0003) and inhibited cell proliferation (P = 0.0069) in vivo. CONCLUSIONS: VES inhibits the growth of colon cancer cells in vitro and in vivo. This is the first report of VES inhibition of colon cancer tumor metastases. The mechanism of VES anti-tumor and anti-metastatic activity in vivo appears to involve promotion of tumor apoptosis and inhibition of cell proliferation. These findings support further investigation of VES as a micronutrient to promote colon cancer tumor dormancy and prevent metastases.


Asunto(s)
Neoplasias del Colon/patología , Neoplasias Hepáticas/prevención & control , Neoplasias Hepáticas/secundario , Vitamina E/análogos & derivados , Vitamina E/farmacología , Animales , Apoptosis/efectos de los fármacos , Carcinoma/prevención & control , División Celular/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/patología , Ratones , Tocoferoles , Células Tumorales Cultivadas
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