2,431 research outputs found
The effect of foreknowledge of demand in case of a restricted capacity: the single-stage, singleproduct case with lost sales
Foreknowledge of demand is useful in the control of a production-inventory system. Knowingthe customer orders in advance makes it possible to anticipate properly. It is an importantcondition to produce and deliver the right quantity of the right product Âjust-in-timeÂ. Itreduces the need of safety stock and spare capacity. But the question of the effectiveness offoreknowledge is not an easy one. Having foreknowledge of the customer orders does notremove the demand uncertainty completely. The effect of foreknowledge has to be consideredin a stochastic dynamic setting. The subject of this paper is the effect of foreknowledge incombination with a restricted production capacity. The lost-sales case is considered. The mainresult is that for high utilization rates and small forecast horizon, the inventory reduction dueto foreknowledge is equal to (1- pi).h, with h the forecast horizon
Decomposed versus integrated control of a one-stage production system
This paper considers the case of a one-stage production system with several products and operating under tight production capacity constraints. The production schedule is cyclical, and there are long and sequence dependent setup times. The production system is regarded to consist of two components, namely a production unit and an inventory unit. The performance, with respect to inventory costs, timing and production quantity determination, of two types of control of the production system are compared, namely so-called decomposed and integrated control. For the generation of production orders, decomposed control uses only information from the inventory unit, while integrated control combines the information from both units. The main conclusion, based on simulation experiments, is that the inventory costs are just slightly lower in case of integrated control. Integration outperforms decomposition with respect to timing and quantity determination. However, since the differences between both approaches are small, the less sophisticated approach of decomposition is preferable when choices between both types of control have to be made.
Clinical evidence of parenteral glutamine supplementation in critical illness
Treballs Finals de Grau de FarmĂ cia, Facultat de FarmĂ cia, Universitat de Barcelona, 2017. Tutor/a: Maria Badia Tahull.[eng] Glutamine is a non-essential amino acid mostly synthetized and released to the blood
stream by the skeletal muscle and the lungs. The enterocytes and the immune system
cells are great glutamine consumers and glutamine is crucial for their correct function.
Due to metabolic changes occurred during critical illness, the plasma level of glutamine
becomes low and skeletal muscle becomes depleted. Treatment with glutamine tries to
normalize plasma levels and improve the immune cell response. Glutamineâs chemical
properties are unfavorable for their storage and so new ways of glutamine delivery are
enveloped. The most current used alternative source are glutamine dipeptides.
Administration of glutamine can be supplying the artificial nutrition support or being
administrated independently; by parenteral or by enteral route. Traditional trials of
glutamine supplementation demonstrate favorable results in patients with critical
illness. However, newer trials which included more study population, among which the
REDOX trial, where not able to confirm these results. A trend towards favorable
outcomes were found in surgical and oncological patients with intravenous glutamine
supplementation on physiological doses without renal and/or liver dysfunction. In
contrast, there was also found high glutamine baseline levels in a subgroup of critically
ill patients. With all the available clinical research information, it is still not clear if
glutamine should be included in the routine clinical use.[cast] La glutamina es un aminoĂĄcido no esencial sintetizado y liberado a la circulaciĂłn
sanguĂnea mayoritariamente por la musculatura esquelĂ©tica y los pulmones. Los
enterocitos y las células del sistema inmunitario son grandes metabolizadores de la
glutamina y Ă©sta es crucial para su funcionamiento Ăłptimo. Debido a cambios
metabĂłlicos sufridos en el paciente crĂtico, los niveles sanguĂneos de glutamina
disminuyen significativamente y se observa una depleciĂłn de glutamina en la
musculatura esquelética. El tratamiento con glutamina tiene como objetivo normalizar
los niveles plasmĂĄticos y mejorar la respuesta del sistema inmunitario. Las propiedades
quĂmicas de la glutamina son desfavorables para su almacenaje y por eso se han
desarrollado nuevas estructuras quĂmicas de glutamina para ser administradas. La
fuente alternativa mås utilizada actualmente son los dipéptidos de glutamina. La
administraciĂłn de glutamina se puede realizar suplementando a la nutriciĂłn artificial o
administrĂĄndose de forma independiente; por vĂa parenteral o bien por vĂa enteral. Los
estudios tradicionales sobre la suplementaciĂłn con glutamina demuestran resultados
favorables en el paciente crĂtico. En cambio, estudios posteriores que incluyen un mayor
nĂșmero de pacientes, entre los cuales destaca el estudio REDOX, no han sido capaces
de confirmar dichos resultados. Los estudios demuestran una tendencia favorable en
pacientes quirĂșrgicos y oncolĂłgicos con suplementaciĂłn de glutamina por vĂa parenteral
en dosis fisiolĂłgicas que no presentaban insuficiencia renal y/o hepĂĄtica. En cambio,
también se han detectado en un subgrupo de pacientes niveles elevados de glutamina.
Aun asĂ, con toda la informaciĂłn clĂnica disponible actualmente, sigue siendo poco
concluyente la inclusiĂłn de la glutamina en la prĂĄctica clĂnica habitual
Convé introduir el PrEP a Espanya?
Premis Pharmanews-Fedefarma 2016La terĂ pia PrEP ha estat aprovada per la European Medicines Agency (EMA) el mes de Juliol del 2016, per ser usada en conjunt amb altres mesures preventives (com el preservatiu) en la reducciĂł del risc dâinfecciĂł del VIH.
SĂłn les autoritats competents de cada paĂs i els seus sistemes sanitaris que han de decidir si volen (o no) incorporar el seu Ășs a la sanitat pĂșblica. França Ă©s lâĂșnic paĂs de la UniĂł Europea on actualment es troba finançat. Al 2012, als Estats Units ja va ser aprovat per la Food and Drug Administration (FDA) i sâha posat en prĂ ctica la seva utilitzaciĂł
Minimizing weighted total earliness, total tardiness and setup costs
The paper considers a (static) portfolio system that satisfies adding-up contraints and the gross substitution theorem. The paper shows the relationship of the two conditions to the weak dominant diagonal property of the matrix of interest rate elasticities. This enables to investigate the impact of simultaneous changes in interest rates on the asset demands.
The effect of foreknowledge of demand in case of a restricted capacity:the single-stage, singleproduct case with lost sales
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