Mediation incomplete information bargaining with filtered communication

We analyze a continuous-time bilateral double auction in the presence of two-sided incomplete information and a smallest money unit. A distinguishing feature of our model is that intermediate concessions are not observable by the adversary: they are only communicated to a passive auctioneer. An alternative interpretation is that of mediated bargaining. We show that an equilibrium using only the extreme agreements always exists and display the necessary and sufficient condition for the existence of (perfect Bayesian) equilibra which yield intermediate agreements. For the symmetric case with uniform type distribution we numerically calculate the equilibria. We find that the equilibrium which does not use compromise agreements is the least efficient, however, the rest of the equilibria yield the lower social welfare the higher number of compromise agreements are used.

Hiperglicemia na intoxicação escorpiônica experimental em cão

The production of hyperglycemia during the acute phase of scorpion poisoning produced by T. bahiensis in dogs is confirmed now. The highest degree on average, was reached 10 minutes after the injection of venom. In our hands, the previous bilateral adrenalectomy did not avoid the hyperglycemia. The average of the blood sugar level has been similar to that observed in dogs with adrenal glands, the highest blood sugar level was also registered after 10 minutes. The hyperglycemia obtained in adrenolectomized dogs is, probably, due to the liberation of Sympatin (Nor-adrenalin and adrenalin) as a consequence of the central excitation by the poison on the hepatic nerves and other ganglionar terminations of the Sympathetic Nervous System. Our present researches suggest that the venom has adrenergic action besides the central action.

Repeated games played in a network

Delayed perfect monitoring in an infinitely repeated discounted game is modelled by letting the players form a connected and undirected network. Players observe their immediate neighbors' behavior only, but communicate over time the repeated game's history truthfully throughout the network. The Folk Theorem extends to this setup, although for a range of discount factors strictly below 1, the set of sequential equilibria and the corresponding payoff set may be reduced. A general class of games is analyzed without imposing restrictions on the dimensionality of the payoff space. This and the bilateral communication structure allow for limited results under strategic communication only. As a by-product this model produces a network result; namely, the level of cooperation in this setup depends on the network's diameter, and not on its clustering coefficient as in other models.

QoS support in satellite and wireless networks: study under the network simulator (NS-2)

Aquest projecte es basa en l'estudi de l'oferiment de qualitat de servei en xarxes wireless i satel·litals. Per això l'estudi de les tècniques de cross-layer i del IEEE 802.11e ha sigut el punt clau per al desenvolupament teòric d’aquest estudi. Usant el simulador de xarxes network simulator, a la part de simulacions es plantegen tres situacions: l'estudi de la xarxa satel·lital, l'estudi del mètode d'accés HCCA i la interconnexió de la xarxa satel·lital amb la wireless. Encara que aquest últim punt, incomplet en aquest projecte, ha de ser la continuació per a futures investigacions.

Patterns of oxygen consumption during establishment of cephalocaudal polarity in the early chick embryo.

Oxygen uptake was studied during the establishment of cephalocaudal polarity in the very early chick embryo, i.e., 10 hr before (stage VI) and at laying (stage X). Oxygen fluxes in minute regions of the intact blastoderms were measured in vitro by scanning microspectrophotometry in the presence or absence of glucose. The oxygen consumption of the whole blastoderm remained constant (6 nmol O2 X hr-1) throughout the period studied, although the number of cells increased more than twofold. The regional oxygen fluxes varied from 0.41 to 1.13 nmol O2 X hr-1 X mm-2 at stage VI and from 0.42 to 0.70 nmol O2 X hr-1 X mm-2 at stage X. At stage VI, the oxygen flux in the center of the blastoderm was significantly higher than that in its periphery. This pattern remained evident when the values were corrected for cell number or for cytoplasmic volume. At stage X, there was a tendency for the oxygen fluxes to decrease from the posterior to the anterior regions of the area pellucida. Thus the pattern of oxidative metabolism in the late uterine embryos seems to change from radial to bilateral. This change of symmetry probably reflects the process of formation of the embryonic axis. In addition, the fact that the oxygen uptake was similar in the presence or absence of glucose suggests that early chick embryos metabolize essentially intracellular stores.

Políticas de encaminamiento tolerantes a fallos

El uso intensivo y prolongado de computadores de altas prestaciones para ejecutar aplicaciones computacionalmente intensivas, sumado al elevado número de elementos que los componen, incrementan drásticamente la probabilidad de ocurrencia de fallos durante su funcionamiento. El objetivo del trabajo es resolver el problema de tolerancia a fallos para redes de interconexión de altas prestaciones, partiendo del diseño de polí­ticas de encaminamiento tolerantes a fallos. Buscamos resolver una determinada cantidad de fallos de enlaces y nodos, considerando sus factores de impacto y probabilidad de aparición. Para ello aprovechamos la redundancia de caminos de comunicación existentes, partiendo desde enfoques de encaminamiento adaptativos capaces de cumplir con las cuatro fases de la tolerancia a fallos: detección del error, contención del daño, recuperación del error, y tratamiento del fallo y continuidad del servicio. La experimentación muestra una degradación de prestaciones menor al 5%. En el futuro, se tratará la pérdida de información en tránsito.

Balanceo distribuido del encaminamiento para topologías fat-tree sobre redes Infiniband

Las redes de interconexión juegan un papel importante en el rendimiento de los sistemas de altas prestaciones. Actualmente la gestión del encaminamiento de los mensajes es un factor determinante para mantener las prestaciones de la red. Nuestra propuesta es trabajar sobre un algoritmo de encaminamiento adaptativo, que distribuye el encaminamiento de los mensajes para evitar los problemas de congestión en las redes de interconexión, que aparecen por el gran volumen de comunicaciones de aplicaciones científicas ó comerciales. El objetivo es ajustar el algoritmo a una topología muy utilizada en los sistemas actuales como lo es el fat‐tree, e implementarlo en una tecnología Infiniband. En la experimentación realizada comparamos el método de control de congestión de la arquitectura Infiniband, con nuestro algoritmo. Los resultados obtenidos muestran que mejoramos los niveles de latencia por encima de un 50% y de throughput entre un 38% y un 81%.

Augment de la resolució en la reconstrucció de les temperatures de l'aigua i de l'aire del llac Baikal (Sibèria) dels últims 60.000 anys

Aquest estudi consisteix en l’augment de la resolució en la reconstrucció de la temperatura de l’aigua i l’aire del llac Baikal durant els últims 60.000 anys mitjançant l’ús de les proxies de reconstrucció de la temperatura TEX86 i MAAT, i la d’aportació de matèria orgànica d’origen terrestre, el BIT. L’objectiu general d’aquesta investigació és incrementar la resolució temporal en el mostreig del testimoni CON-01-603-02 per tal de millorar el registre de dades obtingudes i d’aquesta manera poder contrastar la hipòtesi de la interconnexió climàtica global, així com identificar esdeveniments climàtics sobtats, tals com els Heinrich events i els esdeveniments D-O. Un cop obtinguts els resultats s’ha realitzat l’anàlisi de la qualitat i fiabilitat de les dades a les resolucions de 5, 10 i 20 Kanys, i es conclou que existeixen diferències globals estadísticament significatives amb els resultats realitzats per Escala et al., (r.n.p [resultats no publicats]), la resolució dels quals es volia augmentar. S’han tractat d’anular aquestes diferències restant o bé sumant la diferència mitjana obtinguda entre les dues mostres en cada un dels intervals de 5 Kanys en què s’han donat aquestes. Els resultats integrats d’Escala et al.,(r.n.p) i els d’aquest estudi, aporten dades que recolzen l’hipòtesi de la interconnexió climàtica global, ja que al comparar-los amb els registres climàtics de Grenlàndia (GRIP2) i l’Antàrtica (Vostok) mostren respostes similars tant per les forces de Milankovitch com per les de subMilankovitch.

Pseudohypoaldosteronisms, report on a 10-patient series.

BACKGROUND: Type 1 pseudohypoaldosteronism (PHA1) is a salt-wasting syndrome caused by mineralocorticoid resistance. Autosomal recessive and dominant hereditary forms are caused by Epithelial Na Channel and Mineralocorticoid Receptor mutation respectively, while secondary PHA1 is usually associated with urological problems. METHODS: Ten patients were studied in four French pediatric units in order to characterize PHA1 spectrum in infants. Patients were selected by chart review. Genetic, clinical and biochemistry data were collected and analyzed. RESULTS: Autosomal recessive PHA1 (n = 3) was diagnosed at 6 and 7 days of life in three patients presenting with severe hyperkalaemia and weight loss. After 8 months, 3 and 5 years on follow-up, neurological development and longitudinal growth was normal with high sodium supplementation. Autosomal dominant PHA1 (n = 4) was revealed at 15, 19, 22 and 30 days of life because of failure to thrive. At 8 months, 3 and 21 years of age, longitudinal growth was normal in three patients who were given salt supplementation; no significant catch-up growth was obtained in the last patient at 20 months of age. Secondary PHA1 (n = 3) was diagnosed at 11, 26 days and 5 months of life concomitantly with acute pyelonephritis in three children with either renal hypoplasia, urinary duplication or bilateral megaureter. The outcome was favourable and salt supplementation was discontinued after 3, 11 and 13 months. CONCLUSIONS: PHA1 should be suspected in case of severe hyperkalemia and weight loss in infants and need careful management. Pathogenesis of secondary PHA1 is still challenging and further studies are mandatory to highlight the link between infection, developing urinary tract and pseudohypoaldosteronism.

Autofluorescence Findings Of A Novel Maculopathy In Patient With Spinocerebellar Ataxia Type 1 And Of A Cone - Rod Type Retinal Dysfunction In Three Generation Family With Spinocerebellar Ataxia Type 7

Purpose: To report a novel maculopathy in a patient with SCA1. To describe autofluorescence findings in family with SCA7 and associated cone-rod retinal dysfunction.Methods: 4 affected patients from two families were assessed to investigate a progressive loss of visual acuity (VA). Examinations included fundus photography, autofluorescence (AF) fundus fluorescein angiogragraphy (FFA) and optical coherence tomography. Electroretinogram (full-field) was performed in 2 affected patients. All patients had color vision testing using Ishihara pseudoisochromatic plates. Molecular analysis was performed in family 2.Results: The patient with known diagnosis of SCA1 had a visual acuity of 20/200 bilaterally and dyschromatopsia. He had saccadic pursuit. Fundus examination showed mild retinal pigment epithelium (RPE) changes at the macula. OCT showed bilateral macular serous detachment, which was not obvious at the FFA and explained his VA. AF imaging showed a central hyperfluorescence. The 45 year old proband from family 2 had a visual acuity of 200/20 and dyschromatopsia. ERG testing showed cone type dysfunction of photoreceptors. Her daughter affected at a younger age had the same ERGs findings. Fundus examination showed mild RPE changes in proband, normal findings in her daughter. AF imaging of both patients showed a ring of high density AF around the fovea. The ring was also obvious on near infrared AF. Later onset of gait imbalance led to the diagnosis of SCA7Conclusions: Within the group of spinocerebellar ataxias, only the type 7 is associated with retinal dysfunction. We present the first report of maculopathy associated with SCA1 causing severe vision loss. The ring of high density AF in SCA7 confirmed an early retinal photoreceptor dysfunction in patient with normal fundus.

Scheduling of straddle carriers in a container terminal

Report for the scientific sojourn at the University of California at Berkeley between September 2007 to February 2008. The globalization combined with the success of containerization has brought about tremendous increases in the transportation of containers across the world. This leads to an increasing size of container ships which causes higher demands on seaport container terminals and their equipment. In this situation, the success of container terminals resides in a fast transhipment process with reduced costs. For these reasons it is necessary to optimize the terminal’s processes. There are three main logistic processes in a seaport container terminal: loading and unloading of containerships, storage, and reception/deliver of containers from/to the hinterland. Moreover there is an additional process that ensures the interconnection between previous logistic activities: the internal transport subsystem. The aim of this paper is to optimize the internal transport cycle in a marine container terminal managed by straddle carriers, one of the most used container transfer technologies. Three sub-systems are analyzed in detail: the landside transportation, the storage of containers in the yard, and the quayside transportation. The conflicts and decisions that arise from these three subsystems are analytically investigated, and optimization algorithms are proposed. Moreover, simulation has been applied to TCB (Barcelona Container Terminal) to test these algorithms and compare different straddle carrier’s operation strategies, such as single cycle versus double cycle, and different sizes of the handling equipment fleet. The simulation model is explained in detail and the main decision-making algorithms from the model are presented and formulated.

Accuracy of Brain Multimodal Monitoring to Detect Cerebral Hypoperfusion After Traumatic Brain Injury.

OBJECTIVE:: To examine the accuracy of brain multimodal monitoring-consisting of intracranial pressure, brain tissue PO2, and cerebral microdialysis-in detecting cerebral hypoperfusion in patients with severe traumatic brain injury. DESIGN:: Prospective single-center study. PATIENTS:: Patients with severe traumatic brain injury. SETTING:: Medico-surgical ICU, university hospital. INTERVENTION:: Intracranial pressure, brain tissue PO2, and cerebral microdialysis monitoring (right frontal lobe, apparently normal tissue) combined with cerebral blood flow measurements using perfusion CT. MEASUREMENTS AND MAIN RESULTS:: Cerebral blood flow was measured using perfusion CT in tissue area around intracranial monitoring (regional cerebral blood flow) and in bilateral supra-ventricular brain areas (global cerebral blood flow) and was matched to cerebral physiologic variables. The accuracy of intracranial monitoring to predict cerebral hypoperfusion (defined as an oligemic regional cerebral blood flow < 35 mL/100 g/min) was examined using area under the receiver-operating characteristic curves. Thirty perfusion CT scans (median, 27 hr [interquartile range, 20-45] after traumatic brain injury) were performed on 27 patients (age, 39 yr [24-54 yr]; Glasgow Coma Scale, 7 [6-8]; 24/27 [89%] with diffuse injury). Regional cerebral blood flow correlated significantly with global cerebral blood flow (Pearson r = 0.70, p < 0.01). Compared with normal regional cerebral blood flow (n = 16), low regional cerebral blood flow (n = 14) measurements had a higher proportion of samples with intracranial pressure more than 20 mm Hg (13% vs 30%), brain tissue PO2 less than 20 mm Hg (9% vs 20%), cerebral microdialysis glucose less than 1 mmol/L (22% vs 57%), and lactate/pyruvate ratio more than 40 (4% vs 14%; all p < 0.05). Compared with intracranial pressure monitoring alone (area under the receiver-operating characteristic curve, 0.74 [95% CI, 0.61-0.87]), monitoring intracranial pressure + brain tissue PO2 (area under the receiver-operating characteristic curve, 0.84 [0.74-0.93]) or intracranial pressure + brain tissue PO2+ cerebral microdialysis (area under the receiver-operating characteristic curve, 0.88 [0.79-0.96]) was significantly more accurate in predicting low regional cerebral blood flow (both p < 0.05). CONCLUSION:: Brain multimodal monitoring-including intracranial pressure, brain tissue PO2, and cerebral microdialysis-is more accurate than intracranial pressure monitoring alone in detecting cerebral hypoperfusion at the bedside in patients with severe traumatic brain injury and predominantly diffuse injury.

Official Central Bank Interventions in the Foreign Exchange Markets: A DCC Approach with Exogenous Variables

This paper assesses the impact of official central bank interventions (CBIs) on exchange rate returns, their volatility and bilateral correlations. By exploiting the recent publication of intervention data by the Bank of England, this study is able to investigate fficial interventions by a total number of four central banks, while the previous studies have been limited to three (the Federal Reserve, Bundesbank and Bank of Japan). The results of the existing literature are reappraised and refined. In particular, unilateral CBI is found to be more successful than coordinated CBI. The likely implications of these findings are then discussed.

A Bootstrap Neural Network Based Heterogeneous Panel Unit Root Test: Application to Exchange Rates

This paper proposes a bootstrap artificial neural network based panel unit root test in a dynamic heterogeneous panel context. An application to a panel of bilateral real exchange rate series with the US Dollar from the 20 major OECD countries is provided to investigate the Purchase Power Parity (PPP). The combination of neural network and bootstrapping significantly changes the findings of the economic study in favour of PPP.

The effects of entry in thin markets

We consider entry of additional firms into the market for a single commodity in which both sellers and buyers are permitted to interact strategically. We show that the market is quasi-competitive, in that the inclusion of an additional seller lowers the price and increases the volume of trade, as expected. However, whilst buyers benefit from this change under reasonable conditions on preferences, we cannot conclude that sellers are always made worse off in the face of more intense competition, contrary to the conventional wisdom. We characterize the conditions under which entry by new sellers may raise the equilibrium profit of existing sellers, which will depend in an intuitive way on the elasticity of a strategic analog of demand and the market share of existing sellers, and encompass completely standard economic environments.