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1.
Glob Chang Biol ; 28(2): 509-523, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34713535

RESUMEN

Quantifying the responses of forest disturbances to climate warming is critical to our understanding of carbon cycles and energy balances of the Earth system. The impact of warming on bark beetle outbreaks is complex as multiple drivers of these events may respond differently to warming. Using a novel model of bark beetle biology and host tree interactions, we assessed how contemporary warming affected western pine beetle (Dendroctonus brevicomis) populations and mortality of its host, ponderosa pine (Pinus ponderosa), during an extreme drought in the Sierra Nevada, California, United States. When compared with the field data, our model captured the western pine beetle flight timing and rates of ponderosa pine mortality observed during the drought. In assessing the influence of temperature on western pine beetles, we found that contemporary warming increased the development rate of the western pine beetle and decreased the overwinter mortality rate of western pine beetle larvae leading to increased population growth during periods of lowered tree defense. We attribute a 29.9% (95% CI: 29.4%-30.2%) increase in ponderosa pine mortality during drought directly to increases in western pine beetle voltinism (i.e., associated with increased development rates of western pine beetle) and, to a much lesser extent, reductions in overwintering mortality. These findings, along with other studies, suggest each degree (°C) increase in temperature may have increased the number of ponderosa pine killed by upwards of 35%-40% °C-1 if the effects of compromised tree defenses (15%-20%) and increased western pine beetle populations (20%) are additive. Due to the warming ability to considerably increase mortality through the mechanism of bark beetle populations, models need to consider climate's influence on both host tree stress and the bark beetle population dynamics when determining future levels of tree mortality.


Asunto(s)
Escarabajos , Pinus , Animales , Sequías , Pinus ponderosa , Corteza de la Planta , Árboles
2.
Clin Nutr ; 39(6): 1753-1763, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31409509

RESUMEN

BACKGROUND & AIMS: Short bouts of severe energy restriction may have additional, beneficial cardiometabolic effects beyond that of weight loss. We aimed to assess the short-term effects of intermittent fasting on insulin sensitivity and related cardiometabolic mechanisms. METHODS: This parallel arm, randomized controlled trial compared the short-term effects of intermittent and continuous energy restriction (IER and CER) diets on markers of cardiometabolic health in individuals with central obesity, aiming for equivalent weight loss on both diets. Outcomes were assessed in non-smoking men and women (35-75 y), following 4-wk IER (48 h 600 kcal/d followed by 5-day healthy eating advice) or CER diets (-500 kcal/d healthy eating advice). The primary outcome was the revised quantitative insulin sensitivity check index (R-QUICKI), an indirect estimate of insulin sensitivity. Secondary outcomes included ambulatory blood pressure (ABP), indicators of sympathetic activity (heart rate variability (HRV) and normetanephrine), and markers of glucose homeostasis/insulin resistance, adiposity, lipids and inflammation. RESULTS: Forty-three participants completed the study. Reductions in body weight were equivalent in both groups: mean loss (%) -2.6; 95% CI -3.3, -1.9 and -2.9; -3.6, -2.1 for CER and IER, respectively, P = 0.464). R-QUICKI increased following IER and CER, with no between-diet differences (overall mean increase (%) 6.6; 3.6, 9.6). Fasting plasma glucose concentrations decreased after CER but not after IER (mean difference CER-IER - 4.8% (0.7, 8.9), P < 0.05) and fasting plasma non-esterified fatty acid concentrations were lower after IER compared to CER (mean difference CER-IER 0.15 mmol/L (0.06, 0.24), P < 0.005). There were no differences in lipids, adipokine/inflammatory markers, ABP or HRV between diets. CONCLUSIONS: Short-term CER or IER diets are comparable in their effects on most markers of cardiometabolic risk, although adaptive changes in glucose and fatty acid metabolism occur. This study is registered at clinicaltrials.gov as NCT02679989.


Asunto(s)
Restricción Calórica , Metabolismo Energético , Ayuno , Obesidad Abdominal/dietoterapia , Adulto , Anciano , Biomarcadores/sangre , Glucemia/metabolismo , Presión Sanguínea , Restricción Calórica/efectos adversos , Ayuno/efectos adversos , Ácidos Grasos no Esterificados/sangre , Femenino , Humanos , Insulina/sangre , Resistencia a la Insulina , Londres , Masculino , Persona de Mediana Edad , Obesidad Abdominal/sangre , Obesidad Abdominal/diagnóstico , Obesidad Abdominal/fisiopatología , Factores de Tiempo , Resultado del Tratamiento , Pérdida de Peso
3.
Ecol Appl ; 30(2): e02039, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31802566

RESUMEN

Forest carbon sequestration via forest preservation can be a viable climate change mitigation strategy. Here, we identify forests in the western conterminous United States with high potential carbon sequestration and low vulnerability to future drought and fire, as simulated using the Community Land Model and two high carbon emission scenario (RCP 8.5) climate models. High-productivity, low-vulnerability forests have the potential to sequester up to 5,450 Tg CO2 equivalent (1,485 Tg C) by 2099, which is up to 20% of the global mitigation potential previously identified for all temperate and boreal forests, or up to ~6 yr of current regional fossil fuel emissions. Additionally, these forests currently have high above- and belowground carbon density, high tree species richness, and a high proportion of critical habitat for endangered vertebrate species, indicating a strong potential to support biodiversity into the future and promote ecosystem resilience to climate change. We stress that some forest lands have low carbon sequestration potential but high biodiversity, underscoring the need to consider multiple criteria when designing a land preservation portfolio. Our work demonstrates how process models and ecological criteria can be used to prioritize landscape preservation for mitigating greenhouse gas emissions and preserving biodiversity in a rapidly changing climate.


Asunto(s)
Secuestro de Carbono , Ecosistema , Biodiversidad , Carbono , Cambio Climático , Bosques , Árboles , Estados Unidos
4.
Animals (Basel) ; 9(5)2019 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-31109080

RESUMEN

Farriery is a critical component of healthcare services for working equids. However, in India, an informal workforce, lack of structured training facilities and non-implementation of farriery regulations pose challenges for quality farriery. Brooke India, an equine welfare organisation, has undertaken many initiatives aiming to improve farriery services, including technical training and engagement with equid-owning communities. However, this has met with varying success. The study aimed to identify factors that prevent farriers providing quality farriery services. Focus-group discussions were conducted with farriers from two districts of Uttar Pradesh with varying programme outcomes. Within each area, farriers were grouped according to previous level of engagement with Brooke programmes. Demand for services, farrier status, the external environment and technical training and knowledge were identified as key elements that affected farriery work. These factors were very context specific: in areas where brick kilns provided the majority of customers, recent closures had resulted in an increase in those farriers' feeling of insecurity. A systems approach to improving farriery services, taking these factors into account, is advised. Mentoring-based capacity building, which is closely aligned to farrier needs and expectations, is expected to have positive results in terms of technical skill and farrier engagement.

5.
Animals (Basel) ; 9(4)2019 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-31013717

RESUMEN

Equine ownership is a common income-generating strategy in Pakistan. In Karachi, donkey carts are used to transport building materials, commercial produce and garbage. This study aimed to articulate the role and welfare of donkeys used in waste management. We conducted interviews with donkey owners (n = 200), households which use donkey carts for waste collection (n = 50) and key informants (n = 14). To assess the welfare of donkeys, the Standardised Equine-Based Welfare Assessment Tool (SEBWAT) was used (n = 204). Collection of waste was the primary source of income for 89% of owners interviewed. Of those directly involved in waste collection, 62% were found to be under 18 years of age. During interviews with donkey cart customers the majority reported that there would be a huge garbage build-up if donkey carts were not available. Welfare assessments demonstrated that 52.9% of donkeys had a body condition score of two. Muzzle mutilation was extremely high (78.4%) and 66.7% of donkeys had superficial knee lesions. This is the first study that has explored the role of donkey carts in waste management in Pakistan. The data demonstrate the sizable role that donkey-owning communities play in waste management and the important livelihood option this offers, as well as considerable animal welfare concerns.

6.
Glob Chang Biol ; 25(1): 290-303, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30444042

RESUMEN

Recent prolonged droughts and catastrophic wildfires in the western United States have raised concerns about the potential for forest mortality to impact forest structure, forest ecosystem services, and the economic vitality of communities in the coming decades. We used the Community Land Model (CLM) to determine forest vulnerability to mortality from drought and fire by the year 2049. We modified CLM to represent 13 major forest types in the western United States and ran simulations at a 4-km grid resolution, driven with climate projections from two general circulation models under one emissions scenario (RCP 8.5). We developed metrics of vulnerability to short-term extreme and prolonged drought based on annual allocation to stem growth and net primary productivity. We calculated fire vulnerability based on changes in simulated future area burned relative to historical area burned. Simulated historical drought vulnerability was medium to high in areas with observations of recent drought-related mortality. Comparisons of observed and simulated historical area burned indicate simulated future fire vulnerability could be underestimated by 3% in the Sierra Nevada and overestimated by 3% in the Rocky Mountains. Projections show that water-limited forests in the Rocky Mountains, Southwest, and Great Basin regions will be the most vulnerable to future drought-related mortality, and vulnerability to future fire will be highest in the Sierra Nevada and portions of the Rocky Mountains. High carbon-density forests in the Pacific coast and western Cascades regions are projected to be the least vulnerable to either drought or fire. Importantly, differences in climate projections lead to only 1% of the domain with conflicting low and high vulnerability to fire and no area with conflicting drought vulnerability. Our drought vulnerability metrics could be incorporated as probabilistic mortality rates in earth system models, enabling more robust estimates of the feedbacks between the land and atmosphere over the 21st century.


Asunto(s)
Cambio Climático , Sequías , Incendios , Bosques , Predicción , Modelos Biológicos , Noroeste de Estados Unidos , Sudoeste de Estados Unidos
7.
Proc Natl Acad Sci U S A ; 115(14): 3663-3668, 2018 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-29555758

RESUMEN

Strategies to mitigate carbon dioxide emissions through forestry activities have been proposed, but ecosystem process-based integration of climate change, enhanced CO2, disturbance from fire, and management actions at regional scales are extremely limited. Here, we examine the relative merits of afforestation, reforestation, management changes, and harvest residue bioenergy use in the Pacific Northwest. This region represents some of the highest carbon density forests in the world, which can store carbon in trees for 800 y or more. Oregon's net ecosystem carbon balance (NECB) was equivalent to 72% of total emissions in 2011-2015. By 2100, simulations show increased net carbon uptake with little change in wildfires. Reforestation, afforestation, lengthened harvest cycles on private lands, and restricting harvest on public lands increase NECB 56% by 2100, with the latter two actions contributing the most. Resultant cobenefits included water availability and biodiversity, primarily from increased forest area, age, and species diversity. Converting 127,000 ha of irrigated grass crops to native forests could decrease irrigation demand by 233 billion m3⋅y-1 Utilizing harvest residues for bioenergy production instead of leaving them in forests to decompose increased emissions in the short-term (50 y), reducing mitigation effectiveness. Increasing forest carbon on public lands reduced emissions compared with storage in wood products because the residence time is more than twice that of wood products. Hence, temperate forests with high carbon densities and lower vulnerability to mortality have substantial potential for reducing forest sector emissions. Our analysis framework provides a template for assessments in other temperate regions.


Asunto(s)
Agricultura , Carbono/metabolismo , Cambio Climático , Conservación de los Recursos Naturales , Ecosistema , Agricultura Forestal , Bosques , Incendios
8.
Ecol Appl ; 26(8): 2505-2522, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27907251

RESUMEN

Extensive mortality of whitebark pine, beginning in the early to mid-2000s, occurred in the Greater Yellowstone Ecosystem (GYE) of the western USA, primarily from mountain pine beetle but also from other threats such as white pine blister rust. The climatic drivers of this recent mortality and the potential for future whitebark pine mortality from mountain pine beetle are not well understood, yet are important considerations in whether to list whitebark pine as a threatened or endangered species. We sought to increase the understanding of climate influences on mountain pine beetle outbreaks in whitebark pine forests, which are less well understood than in lodgepole pine, by quantifying climate-beetle relationships, analyzing climate influences during the recent outbreak, and estimating the suitability of future climate for beetle outbreaks. We developed a statistical model of the probability of whitebark pine mortality in the GYE that included temperature effects on beetle development and survival, precipitation effects on host tree condition, beetle population size, and stand characteristics. Estimated probability of whitebark pine mortality increased with higher winter minimum temperature, indicating greater beetle winter survival; higher fall temperature, indicating synchronous beetle emergence; lower two-year summer precipitation, indicating increased potential for host tree stress; increasing beetle populations; stand age; and increasing percent composition of whitebark pine within a stand. The recent outbreak occurred during a period of higher-than-normal regional winter temperatures, suitable fall temperatures, and low summer precipitation. In contrast to lodgepole pine systems, area with mortality was linked to precipitation variability even at high beetle populations. Projections from climate models indicate future climate conditions will likely provide favorable conditions for beetle outbreaks within nearly all current whitebark pine habitat in the GYE by the middle of this century. Therefore, when surviving and regenerating trees reach ages suitable for beetle attack, there is strong potential for continued whitebark pine mortality due to mountain pine beetle.


Asunto(s)
Escarabajos , Ecosistema , Animales , Bosques , Pinus , Dinámica Poblacional , Estaciones del Año
9.
J Environ Manage ; 169: 313-8, 2016 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-26796918

RESUMEN

Natural resource vulnerability to climate change can depend on the climatology and ecological conditions at a particular site. Here we present a conceptual framework for incorporating spatial variability in natural resource vulnerability to climate change in a regional-scale assessment. The framework was implemented in the first regional-scale vulnerability assessment conducted by the US Forest Service. During this assessment, five subregional workshops were held to capture variability in vulnerability and to develop adaptation tactics. At each workshop, participants answered a questionnaire to: 1) identify species, resources, or other information missing from the regional assessment, and 2) describe subregional vulnerability to climate change. Workshop participants divided into six resource groups; here we focus on wildlife resources. Participants identified information missing from the regional assessment and multiple instances of subregional variability in climate change vulnerability. We provide recommendations for improving the process of capturing subregional variability in a regional vulnerability assessment. We propose a revised conceptual framework structured around pathways of climate influence, each with separate rankings for exposure, sensitivity, and adaptive capacity. These revisions allow for a quantitative ranking of species, pathways, exposure, sensitivity, and adaptive capacity across subregions. Rankings can be used to direct the development and implementation of future regional research and monitoring programs. The revised conceptual framework is equally applicable as a stand-alone model for assessing climate change vulnerability and as a nested model within a regional assessment for capturing subregional variability in vulnerability.


Asunto(s)
Cambio Climático , Conservación de los Recursos Naturales , Modelos Teóricos , Bosques , Geografía , Humanos , Recursos Naturales
10.
Vet Surg ; 45(1): 115-20, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26731600

RESUMEN

OBJECTIVE: To describe a technique of canaliculosinostomy into the caudal maxillary sinus to alleviate epiphora secondary to nasolacrimal duct obstruction and to report the long-term outcome in 5 horses. STUDY DESIGN: Case series. ANIMALS: Five client-owned horses. METHODS: Case records of all horses presented for chronic epiphora to a single equine hospital that underwent surgical treatment were reviewed. All included horses had a Jones test or dacryocystography to confirm nasolacrimal duct obstruction. All horses were anesthetized and canaliculosinostomy was created from the medial canthus of the eye into the caudal maxillary sinus using a Steinmann pin and Jacob's chuck. A Foley catheter was placed normograde through the stoma. The inflated bulb held the Foley in place in the sinus, while the proximal end was pulled through the upper eyelid and sutured to the skin on the head. The Foley catheter was maintained in place for 3 weeks and then removed under sedation. RESULTS: Five horses were included. There were no intraoperative difficulties or complications. One horse dislodged the Foley catheter 3 days postoperatively. No other postoperative complications occurred. Followup was available for all horses. One horse was euthanatized for unrelated reasons 10 weeks postoperative at which time epiphora was resolved. The remaining 4 horses had resolution of epiphora at followup (24-46 months postoperative). CONCLUSION: This report describes a simple technique for canaliculosinostomy into the caudal maxillary sinus and long-term outcome in 4 of 5 horses, all of which had resolution of epiphora. This technique can be used to resolve epiphora of various etiologies.


Asunto(s)
Enfermedades de los Caballos/cirugía , Enfermedades del Aparato Lagrimal/veterinaria , Seno Maxilar/cirugía , Animales , Caballos , Enfermedades del Aparato Lagrimal/cirugía , Complicaciones Posoperatorias/cirugía , Complicaciones Posoperatorias/veterinaria , Estudios Retrospectivos
11.
New Phytol ; 206(1): 91-97, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25494578

RESUMEN

Recently, widespread piñon pine die-off occurred in the southwestern United States. Here we synthesize observational studies of this event and compare findings to expected relationships with biotic and abiotic factors. Agreement exists on the occurrence of drought, presence of bark beetles and increased mortality of larger trees. However, studies disagree about the influences of stem density, elevation and other factors, perhaps related to study design, location and impact of extreme drought. Detailed information about bark beetles is seldom reported and their role is poorly understood. Our analysis reveals substantial limits to our knowledge regarding the processes that produce mortality patterns across space and time, indicating a poor ability to forecast mortality in response to expected increases in future droughts.


Asunto(s)
Escarabajos/fisiología , Pinus/fisiología , Estrés Fisiológico , Animales , Clima , Sequías , Geografía , Tallos de la Planta , Suelo , Sudoeste de Estados Unidos , Temperatura , Árboles
12.
Phys Rev Lett ; 110(16): 161801, 2013 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-23679593

RESUMEN

The MiniBooNE experiment at Fermilab reports results from an analysis of ν[over ¯](e) appearance data from 11.27×10(20) protons on target in the antineutrino mode, an increase of approximately a factor of 2 over the previously reported results. An event excess of 78.4±28.5 events (2.8σ) is observed in the energy range 200

13.
Behav Sleep Med ; 8(1): 28-39, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20043247

RESUMEN

People with chronic pain commonly complain of sleep disturbance. This study reports the characteristics of the pain and sleep of a large sample of patients with chronic pain (n = 160). This study compared subgroups of good sleepers with pain (n = 48) and poor sleepers with pain (n = 108). Poor sleepers with pain were younger and reported more pain, pain-related disability, depression, pain-related anxiety, and dysfunctional beliefs about sleep. Using simultaneous regression analysis, this study examined the roles of pain, dysfunctional beliefs about sleep, pain-related disability, depression, and pain-related anxiety in predicting concurrent sleep quality. The findings are relevant to the development of models of sleep disturbance comorbid with chronic pain.


Asunto(s)
Dolor/psicología , Sueño/fisiología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Actitud Frente a la Salud , Enfermedad Crónica , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dolor/complicaciones , Dimensión del Dolor , Escalas de Valoración Psiquiátrica , Análisis de Regresión , Trastornos del Sueño-Vigilia/etiología , Trastornos del Sueño-Vigilia/psicología , Encuestas y Cuestionarios , Adulto Joven
14.
Phys Rev Lett ; 105(18): 181801, 2010 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-21231096

RESUMEN

The MiniBooNE experiment at Fermilab reports results from a search for ¯ν_{µ}→¯ν_{e} oscillations, using a data sample corresponding to 5.66×10²° protons on target. An excess of 20.9±14.0 events is observed in the energy range 475

15.
Phys Rev Lett ; 103(11): 111801, 2009 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-19792365

RESUMEN

The MiniBooNE Collaboration reports initial results from a search for nu(mu)-->nu(e) oscillations. A signal-blind analysis was performed using a data sample corresponding to 3.39x10(20) protons on target. The data are consistent with background prediction across the full range of neutrino energy reconstructed assuming quasielastic scattering, 200

17.
Phys Rev Lett ; 100(3): 032301, 2008 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-18232974

RESUMEN

The observation of neutrino oscillations is clear evidence for physics beyond the standard model. To make precise measurements of this phenomenon, neutrino oscillation experiments, including MiniBooNE, require an accurate description of neutrino charged current quasielastic (CCQE) cross sections to predict signal samples. Using a high-statistics sample of nu_(mu) CCQE events, MiniBooNE finds that a simple Fermi gas model, with appropriate adjustments, accurately characterizes the CCQE events observed in a carbon-based detector. The extracted parameters include an effective axial mass, M_(A)(eff)=1.23+/-0.20 GeV, that describes the four-momentum dependence of the axial-vector form factor of the nucleon, and a Pauli-suppression parameter, kappa=1.019+/-0.011. Such a modified Fermi gas model may also be used by future accelerator-based experiments measuring neutrino oscillations on nuclear targets.

18.
Phys Rev Lett ; 98(23): 231801, 2007 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-17677898

RESUMEN

The MiniBooNE Collaboration reports first results of a search for nu e appearance in a nu mu beam. With two largely independent analyses, we observe no significant excess of events above the background for reconstructed neutrino energies above 475 MeV. The data are consistent with no oscillations within a two-neutrino appearance-only oscillation model.

19.
Phys Rev Lett ; 99(3): 032001, 2007 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-17678280

RESUMEN

The mean life of the positive muon has been measured to a precision of 11 ppm using a low-energy, pulsed muon beam stopped in a ferromagnetic target, which was surrounded by a scintillator detector array. The result, tau(micro)=2.197 013(24) micros, is in excellent agreement with the previous world average. The new world average tau(micro)=2.197 019(21) micros determines the Fermi constant G(F)=1.166 371(6)x10(-5) GeV-2 (5 ppm). Additionally, the precision measurement of the positive-muon lifetime is needed to determine the nucleon pseudoscalar coupling g(P).

20.
Phys Rev Lett ; 92(16): 161802, 2004 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-15169217

RESUMEN

The anomalous magnetic moment of the negative muon has been measured to a precision of 0.7 ppm (ppm) at the Brookhaven Alternating Gradient Synchrotron. This result is based on data collected in 2001, and is over an order of magnitude more precise than the previous measurement for the negative muon. The result a(mu(-))=11 659 214(8)(3) x 10(-10) (0.7 ppm), where the first uncertainty is statistical and the second is systematic, is consistent with previous measurements of the anomaly for the positive and the negative muon. The average of the measurements of the muon anomaly is a(mu)(exp)=11 659 208(6) x 10(-10) (0.5 ppm).

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