555 research outputs found
Barriers, challenges and fears from immigrants in access to healthcare: A proposal for undocumented immigrants to being insured
Access to healthcare is a global issue that needs to be addressed. Worldwide organizations have put efforts in place to overcome this problem and offer solutions and recommendations to various countries. However, these efforts have not been entirely successful. Receiving the highest attainable standard of health or only receiving care is extremely difficult or impossible for individuals who are considered vulnerable such as immigrants, especially those who are undocumented immigrants. Through the recognition of barriers, challenges and fears from immigrants accessing healthcare and a shape of social determinants of health, institutions of government, nonprofit sector and community members organized could grant an opportunity to undocumented immigrants to become a healthier population
A holistic approach to assessment of value of information (VOI) with fuzzy data and decision criteria.
The research presented in this thesis integrates theories and techniques from statistical analysis and artificial intelligence, to develop a more coherent, robust and complete methodology for assessing the value of acquiring new information in the context of the oil and gas industry. The classical methodology for value of information assessment has been used in the oil and gas industry since the 1960s, even though it is only recently that more applications have been published. It is commonly acknowledged that, due to the large number of data acquisition actions and the capital investment associated with it, the oil and gas industry is an ideal domain for developing and applying value of information assessments. In this research, three main gaps in the classical methodology for value of information are identified and addressed by integrating three existing techniques from other domains. Firstly, the research identifies that the technique design of experiments can be used in value of information for providing a holistic assessment of the complete set of uncertain parameters, selecting the ones that have the most impact on the value of the project and supporting the selection of the data acquisition actions for evaluation. Secondly, the fuzziness of the data is captured through membership functions and the expected utility value of each financial parameter is estimated using the probability of the states conditioned to the membership functions - in the classical methodology, this is conditioned to crisp values of the data. Thirdly, a fuzzy inference system is developed for making the value of information assessment, capturing the decision-making human logic into the assessment process and integrating several financial parameters into one. The proposed methodology is applied to a case study describing a value of information assessment in an oil field, where two alternatives for data acquisition are discussed. The case study shows how the three techniques can be integrated within the previous methodology, resulting in a more complete theory. It is observed that the technique or design of experiments provides a full identification of the input parameters affecting the value of the project, and allows a proper selection of the data acquisition actions. In the case study, it is concluded that, when the fuzziness of the data is included in the assessment, the value of the data decreases in comparison with the case where data are assumed to be crisp. This result means that the decision concerning the value of acquiring new data depends on whether the fuzzy nature of the data is included in the assessment, and on the difference between the project value with and without data acquisition. The fuzzy inference system developed for this case study successfully follows the logic of the decision maker and results in a straightforward system to aggregate decision criteria. Sensitivity analysis of the parameters of two different membership functions is made, reaching consistent results in both cases
Modeling corn yields and optimum N rates under variable soil and climatic conditions in the western part of the El Bajio area, Mexico
The objectives of this research were: (1) to test different approaches to characterize the relationship between weather and corn yields and (2) to develop yield models to simulate corn yields and optimal nitrogen rates for two soil groups using historic weather data;Yield data used in this study came from 77 simple fertilizer trials which were carried out with unirrigated corn in farmers\u27 fields in the El Bajio area of central Mexico during the period of 1962-1965;Weather characterization of the light-textured and clay-textured soil areas, into which the region of study was divided, was made according to (1) a soil moisture simulation model by which moisture stress and excess moisture were computed, (2) the amount of rainfall during critical phenological periods for both deficit and excess moisture, and (3) a plant wilting index. Several modifications were made to the soil-moisture-simulation model to adapt it to the area of study in central Mexico;The best approach to characterize weather in the light-textured soils was a plant wilting index, which is a visual method to estimate the degree of wilting in corn plants, followed by the use of rainfall and then the moisture stress index. In the clay-soils area, the weather approaches to characterize excess moisture were very similar. In both approaches, the critical period of excess moisture was found to be early during the vegetative stage of corn;Corn-yield-predicting models developed in this study were evaluated using independent yield data. Corn-yield predicting errors were 374 kg/ha and 539 kg/ha for the best models developed for the light-textured and clay-soils areas, respectively;A weighting procedure which made use of rainfall probabilities was used to determine optimum N fertilizer rates for several locations in the area of study;Corn-yield simulations for varying rooting depths and several locations using historic weather records are discussed
A Holling-Tanner predator-prey model with strong Allee effect
We analyse a modified Holling-Tanner predator-prey model where the predation
functional response is of Holling type II and we incorporate a strong Allee
effect associated with the prey species production. The analysis complements
results of previous articles by Saez and Gonzalez-Olivares (SIAM J. Appl. Math.
59 1867-1878, 1999) and Arancibia-Ibarra and Gonzalez-Olivares (Proc. CMMSE
2015 130-141, 2015)discussing Holling-Tanner models which incorporate a weak
Allee effect. The extended model exhibits rich dynamics and we prove the
existence of separatrices in the phase plane separating basins of attraction
related to co-existence and extinction of the species. We also show the
existence of a homoclinic curve that degenerates to form a limit cycle and
discuss numerous potential bifurcations such as saddle-node, Hopf, and
Bogadonov-Takens bifurcations
Compton degradation of gamma-ray line emission from radioactive isotopes in the classical nova V2491 Cygni
To account for the non-thermal emission from the classical nova V2491 Cygni,
we perform a series of numerical calculations of radiative transfer of
\gamma-ray photons from the radioactive isotope Na in the matter ejected
from a white dwarf. Using a simple wind model for the dynamical evolution of
the ejecta and a monte-carlo code, we calculate radiative transfer of the
\gamma-ray photons in the ejecta. Repeated scattering of the \gamma-ray photons
by electrons in the ejecta, i.e., Compton degradation, results in an extremely
flat spectrum in the hard X-ray range, which successfully reproduces the
observed spectrum of the X-ray emission from V2491 Cygni. The amount of the
isotope Na synthesized in the ejecta is required to be 3\times 10^{-5}
M_\odot to account for the flux of the hard X-ray emission. Our model indicates
that the ejecta become transparent to the \gamma-ray photons within several
tens days. Using the results, we briefly discuss the detectability of the
\gamma-ray line emission by the {\it INTEGRAL} gamma-ray observatory and the
{\it Fermi} Gamma-ray Space Telescope.Comment: 5 pages, 4 figures, to appear in ApJ
New Modulation Technique to Mitigate Common Mode Voltage Effects in Star-Connected Five-Phase AC Drives
Star-connected multiphase AC drives are being considered for electromovility applications such as electromechanical actuators (EMA), where high power density and fault tolerance is demanded. As for three-phase systems, common-mode voltage (CMV) is an issue for multiphase drives. CMV leads to shaft voltages between rotor and stator windings, generating bearing currents which accelerate bearing degradation and produce high electromagnetic interferences (EMI). CMV effects can be mitigated by using appropriate modulation techniques. Thus, this work proposes a new Hybrid PWM algorithm that effectively reduces CMV in five-phase AC electric drives, improving their reliability. All the mathematical background required to understand the proposal, i.e., vector transformations, vector sequences and calculation of analytical expressions for duty cycle determination are detailed. Additionally, practical details that simplify the implementation of the proposal in an FPGA are also included. This technique, HAZSL5M5-PWM, extends the linear range of the AZSL5M5-PWM modulation, providing a full linear range. Simulation results obtained in an accurate multiphase EMA model are provided, showing the validity of the proposed modulation approach.This work has been supported in part by the Government of the Basque Country within the fund for research groups of the Basque University system IT978-16 and in part by the Government of the Basque Country within the research program ELKARTEK as the project ENSOL (KK-2018/00040)
New remains and considerations on Nothrotheriidae from the late Pleistocene of La Ribera, Santa Fe, Argentina
The remains of Nothrotheriidae are very scarce in the fossil record of the Pleistocene of Argentina but the locality La Ribera (late Pleistocene) has an unexpected concentration of members of this family. In this work, an astragalus and a femur assignable to Nothrotheriidae from La Ribera are described as Nothropus cf. carcaranensis Bordas, 1942. Other material of this family of sloths from this locality, among which is the holotype of Nothropus carcaranensis, are reviewed with discussion about the intraspecific variation of the femora. The elements studied herein provide a better understanding of the diversity of the Nothrotheriidae in Argentina.Los restos de Nothrotheriidae son muy escasos en el registro fósil del Pleistoceno de Argentina aunque la localidad La Ribera (Pleistoceno tardío) muestra una inesperada concentración. En este trabajo se describen un nuevo astrágalo y un fémur de Nothrotheriidae de La Ribera como Nothropus cf. carcaranensis Bordas, 1942. Además se revisan los ejemplares de esta familia de perezosos hallados en esta localidad, entre los que se encuentra el holotipo de Nothropus carcaranensis y se discute sobre la variación intraespecífica de los fémures de Nothrotheriidae. El conjunto de elementos aquí reunidos permite avanzar hacia una mejor comprensión sobre la diversidad de Nothrotheriidae en Argentina.Fil: Brambilla, Luciano. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario; ArgentinaFil: Haro, Jose Augusto. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Museo de Paleontología; Argentina. Universidad Nacional de Córdoba. Facultad de Cs.exactas Físicas y Naturales. Departamento de Geología Basica y Aplicada. Cátedra de Paleontología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Ibarra, Damián. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas.; Argentin
Towards an interdisciplinary, intercultural and intergenerational ethno–ornithology for biocultural conservation
La etno–ornitología estudia el complejo de relaciones entre las aves y los seres humanos. Estas interacciones se expresan en distintas dimensiones socio–culturales como el lenguaje, el mito, la ontología y el sentido de lugar de comunidades humanas rurales y urbanas, generando relaciones cotidianas, recíprocas y duraderas entre las aves y la gente. Las aves también se asocian a prácticas sociales como la medicina, la ciencia, la alimentación, las costumbres, el arte y los rituales propios de aquellas zonas donde ellas co–habitan con los humanos. De esta forma, la etno–ornitología entrelaza el mundo natural con la cultura para apreciar dos diversidades del mundo que son normalmente estudiadas y valoradas por separado: la diversidad biológica y la diversidad cultural. En los trabajos etno–ornitológicos, ambas diversidades son apreciadas como una, llamada diversidad biocultural (Maffi 2005). A través del concepto de diversidad biocultural, se ha redescubierto empíricamente, para la ciencia, la estrecha relación entre seres humanos y aves tanto en sus patrones de riqueza como en sus amenazas de conservación (Sutherland 2003). Por ejemplo, a nivel planetario, las zonas con más especies de aves se encuentran espacialmente correlacionadas con las zonas con mayor número de lenguajes humanos (Lirrazalde 2001, Maffi 2005).Fil: Ibarra Eliessetch, José Tomás. Pontificia Universidad Católica de Chile; ChileFil: Pizarro Pinochet, Jose Cristobal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentin
GLANDULA TIROIDES, ¿OTRA VICTIMA DEL COVID-19? A PROPOSITO DE UN CASO
Coronavirus disease compromises all biological organs and systems, either by direct commitment to specific tissues or by indirect effects. The endocrine system is no exception, and parenchyma and thyroid function have been reported to be impaired. In 2003 a histopathological study on the effects of SARS-CoV infection on the thyroid showed extensive damage to parafollicular cells and destruction and exfoliation of epithelial cells in the thyroid follicle, an interesting finding was the absence of an inflammatory infiltrate. which supported the hypothesis of extensive apoptosis responsible for the findings. In China, minimally invasive autopsies of different organs of patients who died of SARS-CoV-2 did not report abnormalities in thyroid follicular morphology, but noted lymphocytic infiltration in the interstitium; none of the tissue immunohistochemistry and PCR analyzes detected SARS-CoV-2 in the thyroid. The first case of thyroid alteration compatible with subacute thyroiditis in a patient with COVID-19 in Peru is presented.La enfermedad por coronavirus compromete todos los órganos y sistemas biológicos, ya sea por compromiso directo a tejidos específicos o por efectos indirectos. El sistema endocrino no es una excepción y la función y parénquima tiroideos se han reportado alterados. En el 2003 un estudio histopatológico sobre los efectos de la infección por SARS-CoV en la tiroides mostró una lesión extensa de las células para-foliculares y la destrucción y exfoliación de las células epiteliales en el folículo tiroideo, un hallazgo interesante fue la ausencia de infiltrado inflamatorio lo que respaldó la hipótesis de una apoptosis extensa responsable de los hallazgos. En China, autopsias mínimamente invasivas de diferentes órganos de pacientes fallecidos por SARS-CoV-2 no informaron anormalidades en la morfología folicular tiroidea, pero notaron infiltración linfocítica en el intersticio; ninguno de los análisis de inmuno-histoquímica tisular y PCR detectó SARS-CoV-2 en la tiroides. Se presenta el primer caso de alteración tiroidea compatible con tiroiditis subaguda en una paciente con COVID-19 en Perú
Overview and Current News in Acute Lymphoblastic Leukemia
The management of acute lymphoblastic leukemia is a challenge in patients of any age range. In the elderly patient, this challenge is further complicated by having to take into account the physical, social, psychological, and emotional factors of this age group, which, together with the complex nature of the disease’s biology, give rise to many questions. Although the diagnostic approach of the disease does not differ from that performed in pediatric or young patients, it does in the determination of risk factors and treatment, since many of the determinants of risk have a different value to that assigned in other patients, and, therefore, we cannot apply all available resources in younger patients to facilitate our work. The genetic alterations of ALL are found more frequently in elderly patients, since age is a factor that increases the risk of presenting these alterations. As an example, the prognostic value of the presence of Philadelphia chromosome (t (9:22)) cannot be weighted at the same scale as in pediatric patients. Comorbidities play another important role when it comes to making therapeutic decisions, and there is currently controversy regarding the use of scores designed to determine the physical and physiological status of elderly subjects. Several analyzes have been carried out to define the value and usefulness of these tools in the older patients with ALL; however, work must still be done in this area. The treatment schemes should be adjusted to the needs and specific characteristics of each individual in advanced age. The use of intensive chemotherapy should be discussed within a multidisciplinary team, always considering the benefit of our patients. In the present chapter, the diverse differences in ALL biology will be addressed when compared with those of children and young adults, and with the impact on the different prognostic determinants and their weight at the time of deciding treatment. The need to apply geriatric tools for decision-making and the therapeutic schemes used around the world for elderly people will also be discussed
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