1,306 research outputs found

    Order processing improvement in military logistics by Value Stream Analysis lean methodology

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    Military logistics is a complex process where response times, demand uncertainty, high variety of material references and cost effectiveness turn decisive for combat capability. Considered as the bridge between the deployed forces and the industrial base that provides materials and services that the forces needed to accomplish their mission, capacity and efficiency of delivery are required for its processes. The required flexibility could only be achieved by improving the Supply Chain Management (SCM) in order to optimize delivery lead times. To cope with these requirements, lean thinking can be extended to military organizations. This research justifies and proposes the use of Lean Six Sigma (LSS) methodologies from manufacturing to optimize logistics processes in the defense sector. In particular, the article presents the benefits and results obtained using Value Stream Analysis and DMAIC (Define, Measure, Analyze, Improve, Control) problem-solving methodology to improve the order processing lead-time as key performance indicator of a military unit delivery fulfilment

    Value stream analysis in military logistics: The improvement in order processing procedure

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    Military logistics is a complex process where response times, demand uncertainty, wide variety of material references, and cost-effectiveness are decisive for combat capability. The demanding flexibility can only be achieved by improving supply chain management (SCM) to minimize lead times. To cope with these requirements, lean thinking can be extended to military organizations. This research justifies and proposes the use of lean methodologies to improve logistics processes with the case study of a military unit. In particular, the article presents the results obtained using value stream mapping (VSM) and value stream design (VSD) tools to improve the order processing lead time of spare items. The procedure starts with an order generation from a military unit that requests the material and ends before transportation to the final destination. The whole project was structured, considering the define-measure-analyze-improve-control (DMAIC) problem-solving methodology. The results show that the future state map might increase added-value activities from 44% to 70%. After implementation, it was demonstrated that the methodology applied reduced the lead-time average and deviation up to 69.6% and 61.9%, respectively

    The RNA-binding protein RBP33 dampens non-productive transcription in trypanosomes

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    In-depth analysis of the transcriptomes of several model organisms has revealed that genomes are pervasively transcribed, giving rise to an abundance of non-canonical and mainly antisense RNA polymerase II-derived transcripts that are produced from almost any genomic context. Pervasive RNAs are degraded by surveillance mechanisms, but the repertoire of proteins that control the fate of these non-productive transcripts is still incomplete. Trypanosomes are single-celled eukaryotes that show constitutive RNA polymerase II transcription and in which initiation and termination of transcription occur at a limited number of sites per chromosome. It is not known whether pervasive transcription exists in organisms with unregulated RNA polymerase II activity, and which factors could be involved in the process. We show here that depletion of RBP33 results in overexpression of similar to 40% of all annotated genes in the genome, with a marked accumulation of sense and antisense transcripts derived from silenced regions. RBP33 loss does not result in a significant increase in chromatin accessibility. Finally, we have found that transcripts that increase in abundance upon RBP33 knockdown are significantly more stable in RBP33-depleted trypanosomes, and that the exosome complex is responsible for their degradation. Our results provide strong evidence that RBP33 dampens non-productive transcription in trypanosomes

    Microwave-assisted solution synthesis, microwave sintering and magnetic properties of cobalt ferrite

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    [EN] A simple, soft, and fast microwave-assisted hydrothermal method was used for the preparation of nanocrystalline cobalt ferrite powders from commercially-available Fe(NO3)(3)center dot 9H(2)O, Co(NO3)(2)center dot 6H(2)O, ammonium hydroxide, and tetrapropylammonium hydroxide (TPAH). The synthesis was conducted in a sealed-vessel microwave reactor specifically designed for synthetic applications, and the resulting products were characterized by XRD, FE-SEM, TEM, and HR-TEM. After a systematic study of the influence of the microwave variables (temperature, reaction time and nature of the bases), highly crystalline CoFe2O4 nanoparticles with a high uniformity in morphology and size, were directly obtained by heating at 130 degrees C for 20 min using the base TPAH. Dense ceramics of cobalt ferrite were prepared by non-conventional, microwave sintering of synthesized nanopowders at temperatures of 850-900 degrees C. The magnetic properties of both the nanopowders and the sintered specimens were determined in order to establish their feasibility as a permanent magnet.This work has been carried out with financial support from the Spanish Ministry of Economy, Industry and Competitiveness (MINECO) and CSIC through the Projects MAT2015-67586-C3-R and NANOMIND, respectively. A. Borrell acknowledges MINECO for a Juan de la Cierva contract (IJCI-2014-19839).Fariñas, JC.; Moreno, R.; Pérez, A.; García, MA.; García-Hernández, M.; Salvador Moya, MD.; Borrell Tomás, MA. (2018). Microwave-assisted solution synthesis, microwave sintering and magnetic properties of cobalt ferrite. Journal of the European Ceramic Society. 38(5):2360-2368. https://doi.org/10.1016/j.jeurceramsoc.2017.12.052S2360236838

    Analysis of polarized 16 O ( → e , e ′ → p ) observables within the relativistic distorted wave impulse approximation

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    Recoil nucleon transferred polarization observables in coincidence quasielastic electron scattering are studied within the relativistic distorted wave impulse approximation. Results for response functions and polarization asymmetries are discussed for proton knockout from p 1 ∕ 2 , p 3 ∕ 2 , and s 1 ∕ 2 shells in 16 O . The impact of spinor distortion is examined by comparing the fully relativistic calculation with results obtained by projecting out the negative-energy components. In particular, a careful analysis of effects linked to the description of the bound and scattered relativistic nucleon wave functions is presented. The high sensitivity of some polarization observables to the dynamical enhancement of the lower components, already shown within the relativistic plane wave impulse approximation, is proven to be maintained in the relativistic distorted wave approach. Semi-relativistic approaches based on the effective momentum approximation are also studied. Finally, comparison with experimental data and a brief analysis of effects linked to medium modified form factors is presented.Dirección Genera de Investigación de España (DGI) y Fondos FEDER. BFM2002-03315, BFM2002-03562, FPA2002-04181-C04- 04, y BFM2000-0600Junta de Andalucía, España y Department of Energy de los EE.UU. DE-FC02-94ER4081

    The pulsating hot subdwarf Balloon 090100001: results of the 2005 multisite campaign

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    We present the results of a multisite photometric campaign on the pulsating sdB star Balloon 090100001. The star is one of the two known hybrid hot subdwarfs with both long- and short-period oscillations. The campaign involved eight telescopes with three obtaining UBVR data, four B-band data, and one Stromgren uvby photometry. The campaign covered 48 nights, providing a temporal resolution of 0.36microHz with a detection threshold of about 0.2mmag in B-filter data. Balloon 090100001 has the richest pulsation spectrum of any known pulsating subdwarf B star and our analysis detected 114 frequencies including 97 independent and 17 combination ones. The strongest mode (f_1) in the 2.8mHz region is most likely radial while the remaining ones in this region form two nearly symmetric multiplets: a triplet and quintuplet, attributed to rotationally split \ell=1 and 2 modes, respectively. We find clear increases of splitting in both multiplets between the 2004 and 2005 observing campaigns, amounting to 15% on average. The observed splittings imply that the rotational rate in Bal09 depends on stellar latitude and is the fastest on the equator. We use a small grid of models to constrain the main mode (f_1), which most likely represents the radial fundamental pulsation. The groups of p-mode frequencies appear to lie in the vicinity of consecutive radial overtones, up to the third one. Despite the large number of g-mode frequencies observed, we failed to identify them, most likely because of the disruption of asymptotic behaviour by mode trapping. The observed frequencies were not, however, fully exploited in terms of seismic analysis which should be done in the future with a larger grid of reliable evolutionary models of hot subdwarfs.Comment: accepted for publication in MNRA

    Hydrological response of a dryland ephemeral river to southern African climatic variability during the last millennium

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    12 páginas, 6 figuras, 2 tablas.-- El PDF del artículo esta en su versión post print.A long-term flood record from the Buffels River, the largest ephemeral river of NW South Africa (9250 km2), was reconstructed based on interpretation of palaeoflood, documentary and instrumental rainfall data. Palaeoflood data were obtained at three study reaches, with preserved sedimentary evidence indicating at least 25 large floods during the last 700 yr. Geochronological control for the palaeoflood record was provided by radiocarbon and optically stimulated luminescence (OSL) dating. Annual resolution was obtained since the 19th century using the overlapping documentary and instrumental records. Large floods coincided in the past within three main hydroclimatic settings: (1) periods of regular large flood occurrence (1 large flood/~30 yr) under wetter and cooler prevailing climatic conditions (AD 1600–1800), (2) decreasing occurrence of large floods (1 large flood/~100 yr) during warmer conditions (e.g., AD 1425–1600 and after 1925), and (3) periods of high frequency of large floods (~ 4–5 large floods in 20–30 yr) coinciding with wetter conditions of decadal duration, namely at AD 1390–1425, 1800–1825 and 1915–1925. These decadal-scale periods of the highest flood frequency seem to correspond in time with changes in atmospheric circulation patterns, as inferred when comparing their onset and distribution with temperature proxies in southern Africa.The study was funded by the 6th Framework Programme of the European Commission through the project “FloodWater recharge of alluvial Aquifers in Dryland Environments”, WADE Project (contract no. GOCE-CT-2003-506680).Peer reviewe

    Donor-derived Strongyloides stercoralis hyperinfection syndrome after simultaneous kidney/pancreas transplantation

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    Most cases of strongyloidiasis associated with solid organ transplantation have been due to the reactivation of a latent infection in the recipient as a result of the immunosuppressive therapy; however, donor-derived infections are becoming increasingly frequent. The case of a patient who nearly died of a Strongyloides stercoralis hyperinfection after receiving simultaneous kidney/pancreas transplants is described herein. No specific parasitological tests were performed pre-transplantation, despite the fact that both the recipient and the donor originated from endemic areas. Serological analysis of the donor's serum performed retrospectively revealed the origin of the infection, which if it had been done beforehand would have prevented the serious complications. Current practice guidelines need to be updated to incorporate immunological and molecular techniques for the rapid screening of Strongyloides prior to transplantation, and empirical treatment with ivermectin should be applied systematically when there is the slightest risk of infection in the donor or recipient

    Chilean sport sciences scientific production indexed in the Web of Science (1981-2016)

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    9 p.Objetivo: realizar un análisis bibliométrico de la producción científica chilena de Ciencias del deporte indexada en la Web of Science hasta 2016. Métodos: se analizaron los artículos y revisiones de Ciencias del deporte de Chile incluidos en los índices de la Colección principal de Web of Science hasta 2016. Los datos se recopilaron y filtraron en el programa Endnote X6 y luego se exportaron a Excel 2013, Bibexcel e Histcite para su análisis. La bibliometría se centró en la productividad, los sujetos y los patrones de colaboración. Resultados: Se encontraron un total de 152 documentos publicados desde 1981 hasta 2016. Las ciencias de la vida fueron el área de investigación principal (104), mientras que la fisiología (36) y la teoría del entrenamiento deportivo (30) fueron los sujetos más representados. La media de autores por artículo fue de 5,26 y el porcentaje de colaboración estuvo principalmente entre el 94% y el 100%. Ramírez-Campillo fue el autor más prolífico (24) y Caniuqueo logró el mayor índice de colaboración (10.83). Se descubrieron dos redes, con 20 y 10 académicos respectivamente y que representan 19 instituciones diferentes. Un grupo de 53 revistas diferentes ha difundido publicaciones de Ciencias del Deporte de Chile, pero 12 de ellas recolectaron el 60.53% de la producción total. Conclusión: la producción científica chilena de Ciencias del Deporte indexada en la Web of Science muestra el desarrollo progresivo y el fortalecimiento de este campo del conocimiento, claramente orientado a las Ciencias de la Vida, el trabajo en equipo y la colaboración internacional. También se debe destacar el establecimiento de una red que incluye académicos de Australia, Brasil, Canadá, Chile y España, que está impulsando la investigación de Ciencias del Deporte en este paísS
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