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Utility computing and Grid are establishing themselves business models where resource providers invest in technology and software platforms. One of the most studied problems is that of efficient resource allocation. Computational efficiency is translated into economical efficiency creating incentives to resource providers to develop nearly optimal resource allocation frameworks. Auctions have proven their ability to do so. Besides, due to the heterogeneity of these environments, some new approaches adopt multiple different auctions to best fit each situation. Our work tries to homogenise scenarios where multiple market mechanisms are present, thus providing to bidders a well-defined bidding specification language that makes their bids independent of the auction mechanism used.

We have characterized the phase behavior of mixtures of the cationic surfactant cetyltrimethylammonium bromide (CTAB) and the organic salt 3-sodium-2-hydroxy naphthoate (SHN) over a wide range of surfactant concentrations using polarizing optical microscopy and X-ray diffraction. A variety of liquid crystalline phases, such as hexagonal, lamellar with and without curvature defects, and nematic, are observed in these mixtures. At high temperatures the curvature defects in the lamellar phase are annealed gradually on decreasing the water content. However, at lower temperatures these two lamellar structures are separated by an intermediate phase, where the bilayer defects appear to order into a lattice. The ternary phase diagram shows a high degree of symmetry about the line corresponding to equimolar CTAB/SHN composition, as in the case of mixtures of cationic and anionic surfactants.

Background: Demonstration of recanalized coronary artery is mostly done by angiographic techniques. Early bedside demonstration of reperfusion after thrombolysis by transthoracic echocardiography (TTE) has important implications in the subsequent risk stratification and timing of coronary interventions. Methods: In this study, 12 patients with acute anterior myocardial infarction who received thrombolytic therapy were studied. Echocardiographic Doppler evaluation of left main coronary artery, proximal left anterior descending coronary artery (LAD), and proximal left circumflex coronary artery were studied before, during, and after thrombolytic therapy. Coronary flow in these arterial segments was assessed both by color flow and velocity measurements. These results were compared with coronary angiographic studies performed within 30 minutes to 48 hours of thrombolysis. Results: Blood flow in left main coronary artery, LAD, and left circumflex coronary artery could be assessed in 9 patients. There was no demonstrable flow in LAD in 6 patients before thrombolysis. In 7 patients flow could be demonstrated in LAD after thrombolysis within 15 minutes to 6 hours. The peak flow velocity in LAD at a localized area of turbulence postthrombolysis varied from 1.8 to 4.5 m/s. One patient showed mosaic color flow in left main coronary artery with a peak velocity of 1.9 m/s before thrombolysis that improved to a laminar flow with a peak velocity of 1.0 m/s after thrombolysis. Two patients showed normal flow in proximal LAD, but no flow in mid-LAD. Two patients did not show any flow in LAD even after 12 hours of thrombolysis. There was good correlation of site of critical narrowing in LAD by TTE with coronary angiography in 6 patients. In 3 patients absent flow in mid-LAD by TTE correlated with total occlusion of either proximal (one patient) or mid-LAD (two patients). Conclusions: Demonstration of recanalized infarct-related left coronary artery soon after thrombolytic therapy is feasible. Locating the actual site of critical narrowing at bedside by TTE has important implications in the subsequent treatment of patients with acute anterior wall myocardial infarction.

We report on the influence of semicrystalline morphology on the physical aging characteristics of poly(phenylene sulfide) or PPS. Specifically, the semicrystalline morphology of PPS was described in terms of a three-phase system comprising a crystalline phase, a mobile-amorphous phase, and a rigid-amorphous phase. The physical aging kinetics were observed to depend on the relative amounts of the mobile-amorphous and rigid-amorphous phases, with accelerated aging rates measured in specimens with higher rigid-amorphous phase fraction. We suggest that the rigid-amorphous phase, which includes chain segments that are more tightly packed relative to the mobile-amorphous phase, is able to accelerate physical aging due to its relative proximity to a state of lower configurational entropy. It is also possible for localized cooperative relaxations within the rigid-amorphous phase to facilitate molecular rearrangements that accelerate the aging process. We also suggest that the configurational entropic state of the mobile- and the rigid-amorphous phases are perhaps more relevant to physical aging in semicrystalline polymers than the proximity of the aging temperature to the glass transition temperatures of the respective phases.

The preparation and characterization (salient ones) of KAl (SO4)2. 12H2O, KCr (SO4)2·12H2O, mixed crystals of both with 10 to 90% of each component, mixed crystals of CsCl with CuCl2, doped crystals of KBr with K3FeCN6, mixed crystals (NH4)2SO4with CuSO4or NiSO4, NaCl with growth improver Pb+2, Mn+2, metallic crystals of Zn, Bi, ionic crystals of alkali halides with Pb+2, or Cd+2, etc. are presented. Instrumentation aspects of a rotary crystallizer, a homogeniser, an ingot release mechanism and a zone refiner are shown.

Perinatal infections with bacteria belonging to the genus campylobacter are being increasingly recognized. We present a case of early onset neonatal sepsis withCampylobacter jejuni(previouslyC. Fetus ss. jejuniorVibrio jejuni). The infant was born prematurely at 31 weeks of gestation and presented with respiratory distress and frequent apnoea from birth. The chest X-ray film demonstrated reticulogranular pattern consistent with hyaline membrane disease. The infant was successfully treated with ampicillin and gentamicin.C. jejuniinfection should be considered in the differential diagnosis of early onset sepsis in the neonate and can mimic the radiological picture of hyaline membrane disease.

To identify the type of feeding that will raise plasma glucose (G) most effectively in the first hours after birth, plasma G was measured before and after first feeding at 4hrs of age. 43 term neonates(NB) were randomized into three groups: 20cc of 5% D/W, 10% D/W or formula (20 cal/oz). Mean±S.D. birth weight was 3158±306gms, length 49.4±1.4cm, head circumference 33.7±1.2cm, gest. age 39.7±1.5wks. Apgar scores ranged from 7 to 9. Six NB were born by C-section and the remaining 37 by vaginal delivery. All infants were healthy and appropriate for gest. age. Plasma glucose was measured prior to and 1, 2, and 4 hrs after feeding and are listed in table:Baseline values prior to feeding were similar in all three groups. A significant rise in glucose values was noted one hour after feeding in all three groups (p<0.05); however, among the three groups, the rise in G values was significantly higher with 10% D/W than with formula or 5% D/W feeds (p<0.05). No difference in G values were noted at 2 & 4hrs after feeding. In conclusion, 10% D/W is the best choice as the first feed for raising G; however, the rise is transient and within 2 hrs, G values are back to baseline regardless of type of feeding.