346 research outputs found
Remote sensing of the Martian surface
Researchers investigated the physical properties of the Martian surface as inferred from a combination of orbiting and earth-based remote sensing observations and in-situ observations. This approach provides the most detailed and self-consistent view of the global and regional nature of the surface. Results focus on the areas of modeling the diurnal variation of the surface temperature of Mars, incorporating the effects of atmospheric radiation, with implications for the interpretation of surface thermal inertia; modeling the thermal emission from particulate surfaces, with application to observations of the surfaces of the Earth, Moon, and Mars; modeling the reflectance spectrum of Mars in an effort to understand the role of particle size in the difference between the bright and dark regions; and determining the slope properties of different terrestrial surfaces and comparing them with planetary slopes derived from radar observations
Access to Eye Care Before and After Vision Loss: A Qualitative Study Investigating Eye Care Among Persons Who Have Become Blind
Navigating access to eye care requires that patients recognize the need for screening and care, employ limited financial and social resources, manage complex health insurance policies, and access specialty clinical care. We investigated the experience of patients through the progression of vision loss to blindness, utilizing qualitative methods. We conducted structured telephone interviews with 28 persons with blindness throughout Oregon. Utilizing closed and open-ended questions, we explored patient experience on the events preceding avoidable blindness. Coding for emergent themes was conducted independently by two researchers using a constant comparative method. Participants described important barriers to accessing eye care: at the systems level, lack of access to providers and treatment; at the community level, available social support and services; and at the individual level, readiness to act and trust in providers. These findings suggest that important barriers to accessing preventive eye care, early diagnosis and treatment, vocational rehabilitation, and social services often occur at multiple levels. Access to eye care should be prioritized in efforts to reduce preventable visual impairment
The application of remote sensing to the inventory of white pine (Pinus strobus L.) in eastern Ohio
Rural Development Through Forestry FundThe University Archives has determined that this item is of continuing value to OSU's history.Remote sensing and Geographic Information Systems technology were successfully used to inventory white pine resources in a 21-county area in eastern Ohio. The inventory required less labor and time than traditional forest inventory techniques and produced acreage and volume estimates with standard errors substantially below those of existing inventories. Conifer stands within the 21-county study area were identified on 1994 Landstat 5 Thematic Mapper images using a maximum likelihood classification algorithm in ERDAS IMAGINE. The validity of the conifer classification; the proportion of white pine; and the area, volume, and other stand characteristics were evaluated by surveys. Within the 21-county study area, 36,454 acres of conifers were identified, 24,147 acres of which were white pine containing 570.5 million board-feet volume. White pine stands in the study area averaged 9.8 acres in size; 37 years in age; 11.7 inches average diameter at breast height; 162 square feet basal area; 23,625 board feet of volume; and had a 35-year white pine site index of 76 feet. These results indicate that Ohio's white pine resource is considerably larger and may have substantially greater economic development potential than previous inventories suggested.School of Natural ResourcesUnited States Department of Agriculture Forest Servic
Patterns of Cost for Patients Dying in the Intensive Care Unit and Implications for Cost Savings of Palliative Care Interventions.
BACKGROUND: Terminal intensive care unit (ICU) stays represent an important target to increase value of care.
OBJECTIVE: To characterize patterns of daily costs of ICU care at the end of life and, based on these patterns, examine the role for palliative care interventions in enhancing value.
DESIGN: Secondary analysis of an intervention study to improve quality of care for critically ill patients.
SETTING/PATIENTS: 572 patients who died in the ICU between 2003 and 2005 at a Level-1 trauma center.
METHODS: Data were linked with hospital financial records. Costs were categorized into direct fixed, direct variable, and indirect costs. Patterns of daily costs were explored using generalized estimating equations stratified by length of stay, cause of death, ICU type, and insurance status. Estimates from the literature of effects of palliative care interventions on ICU utilization were used to simulate potential cost savings under different time horizons and reimbursement models.
MAIN RESULTS: Mean cost for a terminal ICU stay was 39.3K ± 45.1K. Direct fixed costs represented 45% of total hospital costs, direct variable costs 20%, and indirect costs 34%. Day of admission was most expensive (mean 9.6K ± 7.6K); average cost for subsequent days was 4.8K ± 3.4K and stable over time and patient characteristics.
CONCLUSIONS: Terminal ICU stays display consistent cost patterns across patient characteristics. Savings can be realized with interventions that align care with patient preferences, helping to prevent unwanted ICU utilization at end of life. Cost modeling suggests that implications vary depending on time horizon and reimbursement models
Warped Electroweak Breaking Without Custodial Symmetry
We propose an alternative to the introduction of an extra gauge (custodial)
symmetry to suppress the contribution of KK modes to the T parameter in warped
theories of electroweak breaking. The mechanism is based on a general class of
warped 5D metrics and a Higgs propagating in the bulk. The metrics are nearly
AdS in the UV region but depart from AdS in the IR region, towards where KK
fluctuations are mainly localized, and have a singularity outside the slice
between the UV and IR branes. This gravitational background is generated by a
bulk stabilizing scalar field which triggers a natural solution to the
hierarchy problem. Depending on the model parameters, gauge-boson KK modes can
be consistent with present bounds on EWPT for m > 1 TeV at 95% CL. The model
contains a light Higgs mode which unitarizes the four-dimensional theory. The
reduction in the precision observables can be traced back to a large wave
function renormalization for this mode.Comment: 15 pages, 3 figure
X-rays Studies of the Solar System
X-ray observatories contribute fundamental advances in Solar System studies
by probing Sun-object interactions, developing planet and satellite surface
composition maps, probing global magnetospheric dynamics, and tracking
astrochemical reactions. Despite these crucial results, the technological
limitations of current X-ray instruments hinder the overall scope and impact
for broader scientific application of X-ray observations both now and in the
coming decade. Implementation of modern advances in X-ray optics will provide
improvements in effective area, spatial resolution, and spectral resolution for
future instruments. These improvements will usher in a truly transformative era
of Solar System science through the study of X-ray emission.Comment: White paper submitted to Astro2020, the Astronomy and Astrophysics
Decadal Surve
Flavor Phenomenology in General 5D Warped Spaces
We have considered a general 5D warped model with SM fields propagating in
the bulk and computed explicit expressions for oblique and non-oblique
electroweak observables as well as for flavor and CP violating effective
four-fermion operators. We have compared the resulting lower bounds on the
Kaluza-Klein (KK) scale in the RS model and a recently proposed model with a
metric modified towards the IR brane, which is consistent with oblique
parameters without the need for a custodial symmetry. We have randomly
generated 40,000 sets of O(1) 5D Yukawa couplings and made a fit of the quark
masses and CKM matrix elements in both models. This method allows to identify
the percentage of points consistent with a given KK mass, which in turn
provides us with a measure for the required fine-tuning. Comparison with
current experimental data on Rb, FCNC and CP violating operators exhibits an
improved behavior of our model with respect to the RS model. In particular,
allowing 10% fine-tuning the combined results point towards upper bounds on the
KK gauge boson masses around 3.3 TeV in our model as compared with 13 TeV in
the RS model. One reason for this improvement is that fermions in our model are
shifted, with respect to fermions in the RS model, towards the UV brane thus
decreasing the strength of the modifications of electroweak observables.Comment: 28 pages, 7 figures, 4 table
Perspectives on Astrophysics Based on Atomic, Molecular, and Optical (AMO) Techniques
About two generations ago, a large part of AMO science was dominated by
experimental high energy collision studies and perturbative theoretical
methods. Since then, AMO science has undergone a transition and is now
dominated by quantum, ultracold, and ultrafast studies. But in the process, the
field has passed over the complexity that lies between these two extremes. Most
of the Universe resides in this intermediate region. We put forward that the
next frontier for AMO science is to explore the AMO complexity that describes
most of the Cosmos.Comment: White paper submission to the Decadal Assessment and Outlook Report
on Atomic, Molecular, and Optical (AMO) Science (AMO 2020
Suppressing Electroweak Precision Observables in 5D Warped Models
We elaborate on a recently proposed mechanism to suppress large contributions
to the electroweak precision observables in five dimensional (5D) warped
models, without the need for an extended 5D gauge sector. The main ingredient
is a modification of the AdS metric in the vicinity of the infrared (IR) brane
corresponding to a strong deviation from conformality in the IR of the 4D
holographic dual. We compute the general low energy effective theory of the 5D
warped Standard Model, emphasizing additional IR contributions to the wave
function renormalization of the light Higgs mode. We also derive expressions
for the S and T parameters as a function of a generic 5D metric and zero-mode
wave functions. We give an approximate formula for the mass of the radion that
works even for strong deviation from the AdS background. We proceed to work out
the details of an explicit model and derive bounds for the first KK masses of
the various bulk fields. The radion is the lightest new particle although its
mass is already at about 1/3 of the mass of the lightest resonances, the KK
states of the gauge bosons. We examine carefully various issues that can arise
for extreme choices of parameters such as the possible reintroduction of the
hierarchy problem, the onset of nonperturbative physics due to strong IR
curvature or the creation of new hierarchies near the Planck scale. We conclude
that a KK scale of 1 TeV is compatible with all these constraints.Comment: 44 pages, 11 figures, references adde
Genetic connectivity of an endangered shark across nursery areas from the Eastern Tropical Pacific
Defining demographically independent units and understanding gene flow between
them is essential for managing and conserving exploited populations. The scalloped
hammerhead shark, Sphyrna lewini , is a coastal semi-oceanic species found
worldwide in tropical and subtropical waters. Pregnant females give birth in shallow
coastal estuarine habitats that serve as nursery grounds for neonates and small
juveniles, and adults move offshore and become highly migratory. We evaluated the
population structure and connectivity of S. lewini in coastal areas across the Eastern
Tropical Pacific (ETP) using both sequences of the mitochondrial DNA control region
(mtCR) and nuclear-encoded microsatellite loci. The mtCR defined two genetically
discrete geographic groups: the Mexican Pacific and the central-southern Eastern
Tropical Pacific (Guatemala, Costa Rica, Panamá, and Colombia). Overall, the mtCR
data showed low levels of haplotype diversity ranged from 0.000 to 0.608, while
nucleotide diversity ranged from 0.000 to 0.0015. A more fine-grade population
structure analysis was detected using microsatellite loci where Guatemala, Costa Rica,
and Panamá differed significantly. Genetic diversity analysis with nuclear markers
revealed an observed heterozygosity ranging from 0.68 to 0.71 and an allelic richness
from 5.89 to 7.00. Relatedness analysis revealed that individuals within nursery areas
were more closely related than expected by chance, suggesting that S. lewini may
exhibit reproductive philopatric behaviour within the ETP. Findings of at least two
different management units, and evidence of philopatric behaviour call for intensive
conservation actions for this critically endangered species in the ETP.Universidad de Costa Rica/[801-B6-214]/UCR/Costa RicaNational Secretary of Science and Technology/[FID-156]/SENACYT/EcuadorThe Phoenix Zoo/[no.33297]//Estados UnidosPADI Foundation/[no.32809]//Estados UnidosRufford Foundation/[no.22366-1]//Reino UnidosWaitt Foundation/[no.33297]//Estados UnidosFundación Reserva Ojochal/[]//Costa RicaThe Whitley Fund for Nature/[]/WFN/Reino UnidoSandler Family Foundation/[]//Estados UnidosOsa Conservation/[]//Costa RicaUCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de BiologíaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Biología Celular y Molecular (CIBCM)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Ciencias del Mar y Limnología (CIMAR
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