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Better Utilization (good + utilization)
Selected AbstractsResearch, policy and practice: why developing countries are differentJOURNAL OF INTERNATIONAL DEVELOPMENT, Issue 6 2005John Young Better utilization of research and evidence in development policy and practice can help save lives, reduce poverty and improve the quality of life. However, there is limited systematic understanding of the links between research and policy in international development. The paper reviews existing literature and proposes an analytical framework with four key arenas: external influences, political context, evidence and links. Based on the findings of stakeholder workshops in developing countries around the world, the paper identifies four key issues that characterize many developing countries. These are: (i) troubled political contexts; (ii) problems of research supply; (iii) external interference; and (iv) the emergence of civil society as a key player. Despite these challenges, two institutional models seem to be particularly effective: (i) think tanks and (ii) regional networks. Copyright © 2005 John Wiley & Sons, Ltd. [source] Priority-based adaptive routing in NGEO satellite networksINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 3 2007Ömer Korçak Abstract In a non-geostationary satellite constellation with inter satellite links (ISLs), there could be many shortest paths between two satellites in terms of hop count. An efficient routing algorithm should effectively use these paths in order to distribute traffic to ISLs in a balanced way and to improve the performance of the system. This paper presents and evaluates a novel priority-based adaptive shortest path routing (PAR) scheme in order to achieve this goal. PAR sets the path towards the destination in a distributed manner, using a priority mechanism depending on the past utilization and buffering information of the ISLs. Moreover, to avoid unnecessary splitting of a flow and to achieve better utilization of ISLs, enhanced PAR (ePAR) scheme is proposed. This paper evaluates performance of the proposed techniques by employing an extensive set of simulations. Furthermore, since there are a number of ePAR parameters that should be adjusted depending on the network and traffic characteristics, a detailed analysis of ePAR scheme is provided to form a framework for setting the parameters. This paper also includes a method for adaptation of the proposed algorithms to minimum-delay path routing. Copyright © 2006 John Wiley & Sons, Ltd. [source] Improving node behaviour in a QoS control environment by means of load-dependent resource redistributions in LANs,INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 4 2005Bernd E. Wolfinger Abstract An important means to guarantee an acceptable quality of service in networks with real-time communication requirements is the reservation of resources at connection setup time. However, such reserved resources, e.g. transmission bandwidth, may be unused as a consequence of the variations in the actual resource demands. Therefore, a more efficient resource utilization is possible if communicating stations or end-users dynamically hand over some of the free resources temporarily to the other communication partners, e.g. of a ,broadcast network'. This paper concentrates on two fundamental problems of such a demand-based sharing of resources: on the one hand, estimation of the current resource requirement on the basis of load measurements is investigated and, on the other hand, we elaborate efficient algorithms for resource sharing respecting real-time requirements. The algorithms proposed for load estimation and for resource sharing are evaluated analytically with respect to their efficiency for worst-case, average-case and realistic load scenarios. Our approach suggested for resource and traffic management allows one to achieve significantly better utilization of network resources. Copyright © 2005 John Wiley & Sons, Ltd. [source] Queuing analysis of shared-buffer ATM switches with grouped output channelsINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 3 2001Abdullah A. Abonamah Abstract Shared buffering and channel grouping are powerful techniques with great benefits in terms of both performance and implementation. Shared-buffer switches are known to have better performance and better utilization than input or output queued switches. With channel grouping, a cell is routed to a group of channels instead of a specific output channel. In this way, congestion due to output contention can be minimized and the switch performance can therefore be greatly improved. Although each technique is well known by itself in the traditional study of queuing systems, their combined use in ATM networks has not been much explored previously. In this paper, we develop an analytical model for a shared-buffer ATM switch with grouped output channels. The model is then used to study the switch performance in terms of cell loss probability, cell delay and throughput. In particular, we study the impact of the channel grouping factor on the buffer requirements. Our results show that grouping the output channels in a shared-buffer ATM switch leads to considerable savings in buffer space. Copyright © 2001 John Wiley & Sons, Ltd. [source] Influence of dietary polar lipids' quantity and quality on ingestion and assimilation of labelled fatty acids by larval gilthead seabreamAQUACULTURE NUTRITION, Issue 3 2001Izquierdo Dietary supplementation of phospholipids seems to be extremely important to promote growth and survival in fish larvae. Several studies also suggest the importance of n-3 highly unsaturated fatty acids (HUFA) rich phospholipids to further enhance larval performance. In the present study, four different diets were formulated in order to compare the effect of total dietary polar lipid contents, of soya bean lecithin supplementation and of feeding n-3 HUFA in the form of neutral or polar lipids on ingestion and incorporation of labelled fatty acids in gilthead seabream larvae. These diets were prepared including radiolabelled fatty acids from palmitoyl phosphatidylcholine, glycerol trioleate, free oleic acid (FOA) and free eicosapentaenoic acid (FEPA) and were fed to 25 day-old larvae. The results of these experiments showed that the elevation of the dietary polar lipid levels significantly improved microdiet ingestion, regardless of the origins of the polar lipids. This effect caused an improved incorporation of phosphatidylcholine fatty acids to the larval polar and total lipids (TL) as the dietary polar lipids increased. Nevertheless, a better incorporation of fatty acids from dietary polar lipids in comparison with that of fatty acids from dietary triglycerides into larval lipids was found in gilthead seabream, whereas a better utilization of dietary triglycerides fatty acids than dietary free fatty acids could also be observed. Besides, the presence of n-3 HUFA rich neutral lipids (NL) significanlty increased the absorption efficiency of labelled oleic acid from dietary triglycerides, but the presence of n-3 HUFA rich polar lipids, particularly improved the incorporation of FEPA. This fatty acid was preferentially incorporated into larval polar lipids in comparison with FOA. [source] Prognostic Factors for Adult Patients Receiving Extracorporeal Membrane Oxygenation as Mechanical Circulatory Support,A 14-Year Experience at a Medical CenterARTIFICIAL ORGANS, Issue 2 2010Chinchun Lan Abstract Extracorporeal membrane oxygenation (ECMO) is a resource-consuming and highly invasive treatment. There were 1100 ECMO cases at the National Taiwan University Hospital between August 1994 and November 2008. Of these, 607 were adults (>18 years old) who received ECMO as mechanical circulatory support. In this study, patient characteristics and complications during the ECMO course were evaluated for their correlation with prognosis. The following factors were significantly different between survivors and nonsurvivors: age, coronary artery disease, diabetes mellitus, brain death, stroke during ECMO, the need for dialysis during ECMO, pre-ECMO infection, hypoglycemia, acidosis, alkalosis, the need for a distal perfusion catheter, and the amount of red blood cells transfused. Six independent predictors of mortality were identified: age, stroke, the need for dialysis during ECMO, pre-ECMO infection, hypoglycemia, and alkalosis. Our institution has comparatively extensive experience with adult patients, which may be quite different from other medical centers with respect to distribution of patient age. The findings should lead to better utilization of ECMO for adult patients in the future. [source] Näherungsweise Spannungsberechnung vorgespannter BetonbauteileBETON- UND STAHLBETONBAU, Issue 2 2007Olaf Mertzsch PD Dr.-Ing. Mit Einführung der DIN 1045-1 (07.2001) erfolgt die Bemessung von Stahlbeton- und Spannbetontragwerken nach einer einheitlichen Berechnungsvorschrift. Hiermit besteht die Möglichkeit einer besseren Auslastung der Konstruktion. Dies hat zur Folge, dass den Nachweisen der Gebrauchstauglichkeit eine größere Bedeutung zukommt. Ziel der nachfolgenden Betrachtungen ist es, wirklichkeitsnahe Berechnungsansätze zur Vorhersage der Beton- und Stahlspannungen abzuleiten. Diese Berechnungsansätze ermöglichen eine einfache Abschätzung der Spannungen und sind auch für Handrechnungen geeignet. Approximate Stress Calculation of prestressed Concrete Elements With the introduction of the DIN 10451 (07.2001) the dimensioning of reinforced concrete- and prestressed concrete constructions are carried out after an uniform calculation regulation. With this arises the possibiltiy of a much better utilization of the construction. But it has also the consequence that the proof of the usability gets much more importance. Aim of the following paper is it, to derive a realistic calculation-modell for the prognoses of the concrete and steel stresses. A simple estimation of stresses shall be made possible by this and it shall be also suitable for a hand-made calculation. [source] Detailed understanding of enhanced specific antibody productivity in NS0 myeloma cellsBIOTECHNOLOGY & BIOENGINEERING, Issue 1 2009Soo Hean Gary Khoo Abstract The understanding of how cellular productivity is modulated in cell lines is of significant importance in the biopharmaceutical industry. Often, single molecular mechanisms fail to fully explain how specific antibody productivity is enhanced during proliferation arrest. Previously, we reported that certain physiological changes occur when proliferation is arrested by p21CIP1 over expression. In this work, we correlate physiological and molecular factors to enhance antibody productivity. Using biomass, cell volume and total cellular protein content as a basis for determining specific productivity, it was found that total cellular protein correlated best with cellular productivity. This meant that there was no preferential increase in antibody production relative to cellular proteins in arrested cultures. However, molecular analysis of mRNA transcription and stability indicated that both processes were altered in arrested cultures resulting in up to threefold increased heavy chain mRNA levels. While flow cytometric analysis revealed that arrested cells had elevated translational capacity for both heavy and light chains, the heavy to light chain polypeptide ratio was 10,50% higher than in the control. This resulted in a lower extracellular accumulation of light chains and a better utilization of cellular resources for the formation of complete antibodies. Active transcriptional regulation of heavy and light chain mRNA and the modulation of translational activities play a vital role in the modulation of overall antibody productivity of these cells. The combined effect of heavy chain mRNA enhancement and the increased cellular assembly capacity was determined to effectively increase specific productivity. Biotechnol. Bioeng. 2009;102: 188,199. © 2008 Wiley Periodicals, Inc. [source] Need for hospice and palliative care services in patients with end-stage heart failure treated with intermittent infusion of inotropesCLINICAL CARDIOLOGY, Issue 1 2004Angel López-Candales M.D. FACC Abstract Background: Hospice and palliative care programs to relieve suffering and optimize management of terminally ill patients have grown rapidly in the United States. However, there are no data on the need for these services among patients with end-stage heart failure receiving intermittent infusion of intravenous inotropes. Hypothesis: The need for hospice and palliative care programs among patients in end-stage heart failure who receive intermittent infusion of inotropes is investigated. Methods: The study included all stable patients with refractory heart failure symptoms treated with inotropes in our outpatient unit. A total of 73 patients (65 ± 12years; left ventricular ejection fraction 22 ± 9%; New York Heart Association class 3.6 ± 0.4) were seen during a 49-month period. Of these, 3 5 patients (48%) met hospice or palliative care evaluation criteria upon referral but were offered, and accepted, the alternative of parenteral inotropes. In all, 1,737 individual outpatient treatment sessions were given, with a mean of 24 ± 19 sessions per patient (range 5 to 118 sessions), representing a minimum of 9,948 h of inotrope therapy. Results: A total of 18 (25%) patients died, 6 (8%) patients were withdrawn from the program (3 by their primary physicians and 3 because of significant travel limitations); 4 (5%) patients required continuous intravenous home therapy; and 44 (61%) patients were discharged with significant improvement in their heart failure symptoms. Only 7 of the 18 patients who died had received hospice or palliative care intervention, mainly for the sake of comfort and to ease the transition among family members. The rest of the patients were comfortable and had accepted the natural evolution of their disease; they were not interested in or did not require hospice or palliative care intervention. Of the patients discharged from the outpatient cardiac infusion unit, the interval free of heart failure symptoms after the final infusion treatment ranged from 201 to 489 days, with no need for hospitalization or emergency room visits. Conclusion: Our results demonstrate that intermittent infusion of intravenous inotropes can be safely administered and can improve symptoms in a significant number of patients, probably by slowing the natural progression of heart failure. Although the full clinical impact of inotrope therapy in an outpatient setting has not been fully defined, other nonhemodynamic-related benefits should be sought and investigated. Our results suggest that intermittent infusion of intravenous inotropes is one of the prominent variables that requires particular attention. In our experience, the institution of intermittent infusions of intravenous inotropes can, in fact, modify end-stage heart failure symptoms that, in most patients, are currently perceived to lead to a terminal event. Thus, appropriate use of intermittent infusion of intravenous inotropes may not only improve functional class and symptoms in a significant number of patients identified as terminal by their poor response to conventional therapy, but it may also facilitate better utilization of hospice and palliative care resources among patients with end-stage heart failure. Furthermore, the need for hospice and palliative care in patients with heart failure should be revisited in view of adjuvant treatment options such as intermittent infusion of intravenous inotropes. [source] | |||||||||||||