207 research outputs found
Materials Supply System Analysis Under Simulation Scenarios in a Lean Manufacturing Environment
AbstractIdentifying the most efficient supply system for a company working under Lean Manufacturing practices was possible with the support of this work. Promodel software was used to develop simulation model depicting a constant velocity joints (CVJ) production system, where two different supply methods were assessed. According to results herein obtained, better performance is achieved under random supply method in comparison with a clustering supply method. The company’s goal is to keep 1% losses due to lack of material. In the actual process, this essential parameter was reduced from 2.73% to 1.177%, if random supply method is properly implemented
In situ Raman characterization of minerals and degradation processes in a variety of cultural and geological heritage sites
Wetest the capabilities of in situ Raman spectroscopy for non-destructive analysis of degradation processes in invaluable
masterpieces, as well as for the characterization of minerals and prehistoric rock-art in caves. To this
end, we have studied the mechanism of decay suffered by the 15th-century limestone sculptures that decorate
the retro-choir of Burgos Cathedral (N Spain). In situ Raman probe detected hydrated sulfate and nitrateminerals
on the sculptures, which are responsible for the decay of the original limestone. In addition, in situ Raman analyses
were performed on unique speleothems in El Soplao Cave (Cantabria, N Spain) and in the Gruta de las
Maravillas (Aracena, SWSpain). Unusual cavemineralswere detected in El Soplao Cave, such as hydromagnesite
(Mg5(CO3)4(OH)2·4H2O), as well as ferromanganese oxides in the black biogenic speleothems recently discovered
in this cavern. In the Gruta de las Maravillas, gypsum (CaSO4·2H2O) was identified for the first time, as
part of the oldest cave materials, so providing additional evidence of hypogenic mechanisms that occurred in
this cave during earlier stages of its formation. Finally, we present preliminary analyses of several cave paintings
in the renowned “Polychrome Hall” of Altamira Cave (Cantabria, N. Spain). Hematite (Fe2O3) is the most abundant
mineral phase, which provides the characteristic ochre-reddish color to the Altamira bison and deer paintings.
Thus, portable Raman spectroscopy is demonstrated to be an analytical technique compatible with
preserving our cultural and natural heritage, since the analysis does not require physical contact between the
Raman head and the analyzed items
Breast cancer PAM50 signature: Correlation and concordance between RNA-Seq and digital multiplexed gene expression technologies in a triple negative breast cancer series
Background: Full RNA-Seq is a fundamental research tool for whole transcriptome analysis. However, it is too costly and time consuming to be used in routine clinical practice. We evaluated the transcript quantification agreement between RNA-Seq and a digital multiplexed gene expression platform, and the subtype call after running the PAM50 assay in a series of breast cancer patients classified as triple negative by IHC/FISH. The goal of this study is to analyze the concordance between both expression platforms overall, and for calling PAM50 triple negative breast cancer intrinsic subtypes in particular. Results: The analyses were performed in paraffin-embedded tissues from 96 patients recruited in a multicenter, prospective, non-randomized neoadjuvant triple negative breast cancer trial (NCT01560663). Pre-treatment core biopsies were obtained following clinical practice guidelines and conserved as FFPE for further RNA extraction. PAM50 was performed on both digital multiplexed gene expression and RNA-Seq platforms. Subtype assignment was based on the nearest centroid classification following this procedure for both platforms and it was concordant on 96% of the cases (N = 96). In four cases, digital multiplexed gene expression analysis and RNA-Seq were discordant. The Spearman correlation to each of the centroids and the risk of recurrence were above 0.89 in both platforms while the agreement on Proliferation Score reached up to 0.97. In addition, 82% of the individual PAM50 genes showed a correlation coefficient > 0.80. Conclusions: In our analysis, the subtype calling in most of the samples was concordant in both platforms and the potential discordances had reduced clinical implications in terms of prognosis. If speed and cost are the main driving forces then the preferred technique is the digital multiplexed platform, while if whole genome patterns and subtype are the driving forces, then RNA-Seq is the preferred method
The lithium stellarator experiment. TJ-II as a benchmark
In the last years, lithium wall conditioning has been carried out in several fusion devices (Tokamaks, Compact Toruses) by different techniques, providing in many instances record values of plasma parameters and enhanced plasma reproducibility. Behind these findings are the low recycling, low contamination and non-coronal enhanced radiative power dissipation properties of Li. Stellarators are best suited for reactor concepts as far as they basically free from extreme thermal load events. However, the potential problem of impurity accumulation must be taken into account. Therefore, the use of low Z elements as PFC would be highly desirable. In the present work, the plasma performance of the TJ-II Heliac under Li-coated wall conditions with lithium is described. Compared to previous coatings, lithium has produced the best plasma performance to date, leading to the achievement of record values in plasma density and energy confinement. In the present work, the impact of the Li coating operation on reactor relevant issues, such as particle exhaust and retention, high-density operation, confinement characteristics and plasma wall interaction issues is stressed.На протязі останніх років обробку стінок літієм було проведено в кількох термоядерних установках (токамаки, компактні тори) з використанням різних методів, що забезпечило у багатьох випадках одержання плазми з рекордними параметрами та покращеним відтворенням результатів. Ці результати пов’язані з низьким рециклінгом, що властивий літію, слабким забрудненням плазми і підвищеним не корональним поглинанням випромінювання. Стеларатори краще за все підходять для концепції реактора, бо в них у принципі не може бути підвищених теплових навантажень. Але треба враховувати можливість накопичення домішок. Тому конче бажано в поверхнях, які повернені до плазми, використовувати елементи з низьким Z. В даній роботі описано експерименти по одержанню плазми в геліаку TJ-II в умовах покриття стінок літієм. Порівняно з покриттями, що використовувалися раніше, літій забезпечив одержання плазми з найкращими на даний час параметрами, дозволивши досягти рекордних значень гущини плазми та утримання енергії. Підкреслена важливість літієвого покриття для таких аспектів реактора, як втрати і затримування частинок, робота при високій гущині, характеристики утримання та взаємодія плазма-стінка.В течение последних лет обработка стенок литием была проведена в нескольких термоядерных установках (токамаки, компактные торы) с использованием различных методов, что обеспечило во многих случаях получение плазмы с рекордными параметрами и улучшенной воспроизводимостью результатов. Эти результаты связаны со свойственными литию низким рециклингом, слабым загрязнением плазмы и повышенным не корональным поглощением излучения. Стеллараторы лучше всего подходят для концепции реактора, ибо у них в принципе не может быть повышенных тепловых нагрузок. Однако, необходимо учитывать возможность накопления примесей. Поэтому весьма желательно в поверхностях, обращённых к плазме, использовать элементы с низким Z. В настоящей работе описаны эксперименты по получению плазмы в гелиаке TJ-II в условиях покрытия стенок литием. По сравнению с покрытиями, которые использовались раньше, литий обеспечил получение плазмы с наилучшими в настоящее время параметрами, позволив достичь рекордных значений плотности плазмы и удержания энергии. Подчёркивается важность литиевого покрытия для таких аспектов реактора, как расход и удерживание частиц, работа при большой плотности, характеристики удержания и взаимодействие плазма-стенка
Consenso colombiano de atención, diagnóstico y manejo de la infección por SARS-COV-2/COVID-19 en establecimientos de atención de la salud Recomendaciones basadas en consenso de expertos e informadas en la evidencia
The “Asociación Colombiana de Infectología” (ACIN) and the “Instituto de Evaluación de Nuevas Tecnologías de la Salud” (IETS) created a task force to develop recommendations for Covid 19 health care diagnosis, management and treatment informed, and based, on evidence. Theses reccomendations are addressed to the health personnel on the Colombian context of health services. © 2020 Asociacion Colombiana de Infectologia. All rights reserved
Peabody Picture Vocabulary Test-III: Normative data for Spanish-speaking pediatric population
OBJECTIVE: To generate normative data for the Peabody Picture Vocabulary Test-III (PPVT-III) in Spanish-speaking
pediatric populations.
METHOD: The sample consisted of 4,373 healthy children from nine countries in Latin America (Chile, Cuba, Ecuador,
Honduras, Guatemala, Mexico, Paraguay, Peru, and Puerto Rico) and Spain. Each participant was administered the PPVT-III
as part of a larger neuropsychological battery. PPVT-III scores were normed using multiple linear regressions and standard
deviations of residual values. Age, age2, sex, and mean level of parental education (MLPE) were included as predictors in
the analyses.
RESULTS: The final multiple linear regression models showed main effects for age in all countries, such that scores increased
linearly as a function of age. In addition, age2 had a significant effect in all countries, except Guatemala and Paraguay. Models
showed that children whose parent(s) had a MLPE >12 years obtained higher scores compared to children whose parent(s)
had a MLPE ≤12 years in all countries, except for Cuba, Peru, and Puerto Rico. Sex affected scores for Chile, Ecuador,
Guatemala, Mexico, and Spain.
CONCLUSIONS: This is the largest Spanish-speaking pediatric normative study in the world, and it will allow neuropsychologists from these countries to have a more accurate interpretation of the PPVT-III when used in pediatric populations
Anisotropy studies around the galactic centre at EeV energies with the Auger Observatory
Data from the Pierre Auger Observatory are analyzed to search for
anisotropies near the direction of the Galactic Centre at EeV energies. The
exposure of the surface array in this part of the sky is already significantly
larger than that of the fore-runner experiments. Our results do not support
previous findings of localized excesses in the AGASA and SUGAR data. We set an
upper bound on a point-like flux of cosmic rays arriving from the Galactic
Centre which excludes several scenarios predicting sources of EeV neutrons from
Sagittarius . Also the events detected simultaneously by the surface and
fluorescence detectors (the `hybrid' data set), which have better pointing
accuracy but are less numerous than those of the surface array alone, do not
show any significant localized excess from this direction.Comment: Matches published versio
Evidence for a mixed mass composition at the `ankle' in the cosmic-ray spectrum
We report a first measurement for ultra-high energy cosmic rays of the
correlation between the depth of shower maximum and the signal in the water
Cherenkov stations of air-showers registered simultaneously by the fluorescence
and the surface detectors of the Pierre Auger Observatory. Such a correlation
measurement is a unique feature of a hybrid air-shower observatory with
sensitivity to both the electromagnetic and muonic components. It allows an
accurate determination of the spread of primary masses in the cosmic-ray flux.
Up till now, constraints on the spread of primary masses have been dominated by
systematic uncertainties. The present correlation measurement is not affected
by systematics in the measurement of the depth of shower maximum or the signal
in the water Cherenkov stations. The analysis relies on general characteristics
of air showers and is thus robust also with respect to uncertainties in
hadronic event generators. The observed correlation in the energy range around
the `ankle' at differs significantly from
expectations for pure primary cosmic-ray compositions. A light composition made
up of proton and helium only is equally inconsistent with observations. The
data are explained well by a mixed composition including nuclei with mass . Scenarios such as the proton dip model, with almost pure compositions, are
thus disfavoured as the sole explanation of the ultrahigh-energy cosmic-ray
flux at Earth.Comment: Published version. Added journal reference and DOI. Added Report
Numbe
Atmospheric effects on extensive air showers observed with the Surface Detector of the Pierre Auger Observatory
Atmospheric parameters, such as pressure (P), temperature (T) and density,
affect the development of extensive air showers initiated by energetic cosmic
rays. We have studied the impact of atmospheric variations on extensive air
showers by means of the surface detector of the Pierre Auger Observatory. The
rate of events shows a ~10% seasonal modulation and ~2% diurnal one. We find
that the observed behaviour is explained by a model including the effects
associated with the variations of pressure and density. The former affects the
longitudinal development of air showers while the latter influences the Moliere
radius and hence the lateral distribution of the shower particles. The model is
validated with full simulations of extensive air showers using atmospheric
profiles measured at the site of the Pierre Auger Observatory.Comment: 24 pages, 9 figures, accepted for publication in Astroparticle
Physic
The exposure of the hybrid detector of the Pierre Auger Observatory
The Pierre Auger Observatory is a detector for ultra-high energy cosmic rays.
It consists of a surface array to measure secondary particles at ground level
and a fluorescence detector to measure the development of air showers in the
atmosphere above the array. The "hybrid" detection mode combines the
information from the two subsystems. We describe the determination of the
hybrid exposure for events observed by the fluorescence telescopes in
coincidence with at least one water-Cherenkov detector of the surface array. A
detailed knowledge of the time dependence of the detection operations is
crucial for an accurate evaluation of the exposure. We discuss the relevance of
monitoring data collected during operations, such as the status of the
fluorescence detector, background light and atmospheric conditions, that are
used in both simulation and reconstruction.Comment: Paper accepted by Astroparticle Physic
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