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Health of American Indian and Alaska Native Elders in California
Analyzes the health risks, health status, and utilization of and access to health services among American Indians/Alaska Natives age 55 and older in California, as well as trends in demographics and underlying factors including economic security
Siglec receptors impact mammalian lifespan by modulating oxidative stress.
Aging is a multifactorial process that includes the lifelong accumulation of molecular damage, leading to age-related frailty, disability and disease, and eventually death. In this study, we report evidence of a significant correlation between the number of genes encoding the immunomodulatory CD33-related sialic acid-binding immunoglobulin-like receptors (CD33rSiglecs) and maximum lifespan in mammals. In keeping with this, we show that mice lacking Siglec-E, the main member of the CD33rSiglec family, exhibit reduced survival. Removal of Siglec-E causes the development of exaggerated signs of aging at the molecular, structural, and cognitive level. We found that accelerated aging was related both to an unbalanced ROS metabolism, and to a secondary impairment in detoxification of reactive molecules, ultimately leading to increased damage to cellular DNA, proteins, and lipids. Taken together, our data suggest that CD33rSiglecs co-evolved in mammals to achieve a better management of oxidative stress during inflammation, which in turn reduces molecular damage and extends lifespan
Impedance measurements and simulations on the TCT and TDI LHC collimators
The LHC collimation system is a critical element for
the safe operation of the LHC machine and it is subject
to continuous performance monitoring, hardware upgrade
and optimization. In this work we will address the impact
on impedance of the upgrades performed on the injection
protection target dump (TDI), where the absorber material
has been changed to mitigate the device heating observed
in machine operation, and on selected secondary (TCS) and
tertiary (TCT) collimators, where beam position monitors
(BPM) have been embedded for faster jaw alignment. Con-
cerning the TDI, we will present the RF measurements per-
formed before and after the upgrade, comparing the result
to heating and tune shift beam measurements. For the TCTs,
we will study how the higher order modes (HOM) intro-
duced by the BPM addition have been cured by means of
ferrite placement in the device. The impedance mitigation
campaign has been supported by RF measurements whose
results are in good agreement with GdfidL and CST simula-
tions. The presence of undamped low frequency modes is
proved not to be detrimental to the safe LHC operation
Anomalous relaxations and chemical trends at III-V nitride non-polar surfaces
Relaxations at nonpolar surfaces of III-V compounds result from a competition
between dehybridization and charge transfer. First principles calculations for
the (110) and (100) faces of zincblende and wurtzite AlN, GaN and InN
reveal an anomalous behavior as compared with ordinary III-V semiconductors.
Additional calculations for GaAs and ZnO suggest close analogies with the
latter. We interpret our results in terms of the larger ionicity (charge
asymmetry) and bonding strength (cohesive energy) in the nitrides with respect
to other III-V compounds, both essentially due to the strong valence potential
and absence of core states in the lighter anion. The same interpretation
applies to Zn II-VI compounds.Comment: RevTeX 7 pages, 8 figures included; also available at
http://kalix.dsf.unica.it/preprints/; improved after revie
Caracterización fitoquímica de factores antinutricionales en las hojas de uvito (cordia dentata poir)
Objetivo. Establecer factores antinutricionales en la biomasa de uvito (Cordia dentata Poir), y su valor nutricional e impacto en el bienestar animal, mediante experimentos de producción de gas. Materiales y Métodos. La recolección de hojas de C. dentata se llevó a cabo en dos épocas del año, correspondientes al periodo de verano (marzo) y lluvioso (septiembre), en el municipio de Codazzi (Cesar). Adicionalmente se realizó un muestreo de pasto Colosuana (Bothriochloa pertusa) que fue utilizado como forraje control. En las diferentes muestras se determinó la concentración de taninos, saponinas, alcaloides, nitratos y nitritos. Posteriormente, en ensayos de producción de gas in vitro, se cuantificó el impacto nutricional de diferentes concentraciones de los componentes antinutricionales mayoritarios identificados en la primera fase. Resultados. Los análisis realizados en este estudio indicaron que el uvito es un forraje degradable y una buena fuente de proteína aprovechable (16.8%) y que los contenidos de saponinas, alcaloides y taninos no deben ser considerados factores antinutricionales en esta especie. Sin embargo, la concentración de nitratos fue catalogada como potencialmente tóxica, condición que debe ser un factor a tener en cuenta al momento de incluir esta especie en la dieta de rumiantes. La cantidad de gas producido en los experimentos se vio afectada negativamente por la presencia de los nitratos contenidos en las hojas de C. dentata. Conclusiones. El uvito () puede ser incluido en la dieta de bovinos, teniendo muy en cuenta el control de los nitratos en el total de la dieta
Feedback Control Methods on Short-Period Orbits Of the Earth-Moon Equilateral Libration Points
Recent research by the authors suggests a unique approach to perform Lunar occultations for a diverse set of scientific applications. Under the circular restricted three-body problem assumptions, short-period orbits (SPOs) near the Earth-Moon equilateral Libration points have been suggested for optimal eclipse time and minimal fuel consumption requirements to stay in orbit. Nevertheless, under the presence of orbital perturbations, SPOs are no longer stable as gravitational effects from neighboring celestial bodies continuously perturb these orbits. In this sense, the current study compares a wide range of control methods, including Lyapunov-based adaptive control schemes and fuel-optimal control policies, to address the fuel consumption and tracking issues of the perturbed system. This inquiry attests that perturbations are effectively cancelled out to achieve the proposed scientific objectives with minimal station-keeping requirements
Effect of ω-3 and ω-9 fatty acid rich oils on lipoxygenases and cyclooxygenases enzymes and on the growth of a mammary adenocarcinoma model
Background Nutritional factors play a major role in cancer initiation and development. Dietary polyunsaturated fatty acids (PUFAs) have the ability to induce modifications in the activity of lipoxygenase (LOX) and cyclooxygenase (COX) enzymes that affect tumour growth. We studied the effect of two diets enriched in 6% Walnut and Peanut oils that are rich in ω-3 and ω9 PUFAs respectively on a murine mammary gland adenocarcinoma as compared with the control (C) that received commercial diet. Results Peanut oil enriched diet induced an increase in membrane arachidonic acid (AA) content and the cyclooxygenase enzyme derived 12-HHT (p < 0.05) and simultaneously showed decrease in 12-LOX, 15-LOX-2, 15-LOX-1 and PGE activities (p < 0.05) that corresponded to higher apoptosis and lower mitosis seen in this group (p < 0.05). Furthermore, Peanut oil group showed lower T-cell infiltration (p < 0.05), number of metastasis (p < 0.05) and tumour volume (p < 0.05) and longer survival rate compared to other groups. Conclusions The results of the present study showed that Peanut oil-enriched diet protects against mammary cancer development by modulating tumour membrane fatty acids composition and LOX and COX enzyme activities.Fil: Comba, Andrea. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Biología Celular; Argentina. Universidad Nacional de Córdoba. Facultad de Medicina. Cátedra de Histología,embriología y Genética I; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Maestri, Damian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Berra, María Alejandra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Biología Celular; Argentina. Universidad Nacional de Córdoba. Facultad de Medicina. Cátedra de Histología,embriología y Genética I; ArgentinaFil: Garcia, Carolina Paola. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Biología Celular; Argentina. Universidad Nacional de Córdoba. Facultad de Medicina. Cátedra de Histología,embriología y Genética I; ArgentinaFil: Das, Undurti N.. Jawaharlal Nehru Technological University; India. Undurti Narasimha Das; Estados Unidos. Krishna Institute of Medical Sciences; IndiaFil: Eynard, Aldo Renato. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Biología Celular; Argentina. Universidad Nacional de Córdoba. Facultad de Medicina. Cátedra de Histología,embriología y Genética I; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Pasqualini, María Eugenia. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Biología Celular; Argentina. Universidad Nacional de Córdoba. Facultad de Medicina. Cátedra de Histología,embriología y Genética I; Argentin
Phase Referencing in Optical Interferometry
One of the aims of next generation optical interferometric instrumentation is
to be able to make use of information contained in the visibility phase to
construct high dynamic range images. Radio and optical interferometry are at
the two extremes of phase corruption by the atmosphere. While in radio it is
possible to obtain calibrated phases for the science objects, in the optical
this is currently not possible. Instead, optical interferometry has relied on
closure phase techniques to produce images. Such techniques allow only to
achieve modest dynamic ranges. However, with high contrast objects, for faint
targets or when structure detail is needed, phase referencing techniques as
used in radio interferometry, should theoretically achieve higher dynamic
ranges for the same number of telescopes. Our approach is not to provide
evidence either for or against the hypothesis that phase referenced imaging
gives better dynamic range than closure phase imaging. Instead we wish to
explore the potential of this technique for future optical interferometry and
also because image reconstruction in the optical using phase referencing
techniques has only been performed with limited success. We have generated
simulated, noisy, complex visibility data, analogous to the signal produced in
radio interferometers, using the VLTI as a template. We proceeded with image
reconstruction using the radio image reconstruction algorithms contained in
AIPS IMAGR (CLEAN algorithm). Our results show that image reconstruction is
successful in most of our science cases, yielding images with a 4
milliarcsecond resolution in K band. (abridged)Comment: 11 pages, 36 figure
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