Cerebral emboli and serum S100beta during cardiac operations

BACKGROUND: The glial protein S100beta has been used to estimate cerebral damage in a number of clinical settings. The purpose of this investigation was to determine the correlation between cerebral microemboli and S100beta levels during cardiac operations. METHODS: Transcranial Doppler ultrasonography was used to measure emboli in the right middle cerebral artery. Emboli counts (n = 111) were divided into five time periods: (1) incision to aortic cannulation; (2) aortic cannulation to cross-clamp onset; (3) cross-clamp onset to cross-clamp release; (4) cross-clamp release to decannulation; and (5) decannulation to chest closure. The level of S100beta (n = 156) was measured at baseline, at the end of cardiopulmonary bypass, then 150 and 270 minutes after cross-clamp release. RESULTS: The level of S100beta correlated with age, cardiopulmonary bypass time, cross-clamp time, and number of emboli at time period 2. Although cardiopulmonary bypass time was univariately associated with S100beta level, it became nonsignificant in a multivariable model that included age and cross-clamp time. CONCLUSIONS: The correlation of S100beta level with emboli measured during cannulation (time period 2) supports the hypothesis that cannulation is a high-risk time period for cerebral injury.     

Radiosity for dynamic scenes in flatland with the visibility complex

The radiosity method is particularly suitable for global illumination calculations in static environments. Nonetheless, recent applications of image synthesis such as architectural simulation or lighting design require the ability to modify environments. Previous methods have attempted to deal with dynamic environments (environments where the geometry, the material properties, etc., can change)but still suffer some limitations in the case of moving objects. One of the main problems remaining is the efficient and accurate detection of which form factors must really be recomputed, since their calculation is the most time-consuming part of the radiosity method. To correctly understand and solve this problem, we start with a method in 2D for polygonal scenes using the visibility complex. It is a powerful data structure representing the visibility relationships between objects in the plane. We have developed and implemented an algorithm which uses this structure to efficiently compute the discontinuity mesh and the form factors for static scenes. We also propose an extension to our algorithm to efficiently update only the modified form factors when an object is moving. This approach enhances our understanding and will hopefully lead to efficient solutions in 3D.     

Un modèle statistique pour les échos réverbérés par une surface fluctuante aléatoire

The authors have treated a statistical model which describes time intervals distribution between successive echos scattered by a fluctuating surface. A sonar signal scattered by sea surface is taken as a practical example. It is shown that scattered echos are achieved by random deleting of transmitted signals.     

Isolation of a lactone,structurally related to the esterifying acids of pyrrolizidine alkaloids,from the costal fringes of male Ithomiinae

Adult male Ithomiinae feed at plants containing pyrrolizidine alkaloids. Certain species secrete on hairs of the costal fringe, a specialized organ on their hindwings, a novel -lactone structurally related to the unusual branched-chain acids that are unique to these alkaloids.     

Poly(β-malic acid) : a new polymeric drug-carrier

Summary Poly(-malic acid) is a new synthetic functional polyester of the poly(-hydroxy-acid)-type whose properties are investigated in regard to possible uses as bioresorbable polyvalent drug-carrier. Degradation of polymer chains in 0.15 N phosphate buffer at pH=7.5 is monitored by aqueous GPC on SEPHADEX gels and by enzymatic titration of ultimate degradation products. It is shown that the rate of degradation obeys first order kinetics at the begining and that poly(-malic acid) degrades to malic acid at last.Presented at the 26th IUPAC Microsymposium on Macromolecules: Polymers in Medicine and Biology, Prague, July 9–12, 1984     

Positron emission tomography for the evaluation of pancreatic disease

Efficient techniques for native-labeling of amino acids have been combined successfully with emission tomography to yield significant improvements in pancreatic imaging. Carbon-11-labeled tryptophan appears to be the best agent available currently for imaging the pancreas. Optimum scanning times begin 30 min after tracer administration. Positron emission tomography with 11C-tryptophan is capable of defining both morphological and functional alterations in the pancreas. Tumors as small as 2 cm in diameter can be detected, but reliable differentiation of pancreatic cancer from pancreatis may not be possible even with this improved imaging technique. Longitudinal multiplane emission tomography in single-photon mode with the Pho/Con provides an efficient and satisfactory approach to pancreatic imaging with the positron-emitting radiopharmaceuticals.     

Engineered polymeric nanoparticles for soil remediation

Hydrophobic organic groundwater contaminants, such as polynuclear aromatic hydrocarbons (PAHs), sorb strongly to soils and are difficult to remove. We report here on the synthesis of amphiphilic polyurethane (APU) nanoparticles for use in remediation of soil contaminated with PAHs. The particles are made of polyurethane acrylate anionomer (UAA) or poly(ethylene glycol)-modified urethane acrylate (PMUA) precursor chains that can be emulsified and cross-linked in water. The resulting particles are of colloidal size (17-97 nm as measured by dynamic light scattering). APU particles have the ability to enhance PAH desorption and transport in a manner comparable to that of surfactant micelles, but unlike the surface-active components of micelles, the individual cross-linked precursor chains in APU particles are not free to sorb to the soil surface. Thus, the APU particles are stable independent of their concentration in the aqueous phase. In this paper we show that APU particles can be engineered to achieve desired properties. Our experimental results show that the APU particles can be designed to have hydrophobic interior regions that confer a high affinity for phenanthrene (PHEN) and hydrophilic surfaces that promote particle mobility in soil. The affinity of APU particles for contaminants such as PHEN can be controlled by changing the size of the hydrophobic segment used in the chain synthesis. The mobility of colloidal APU suspensions in soil is controlled by the charge density or the size of the pendent water-soluble chains that reside on the particle surface. Exemplary results are provided illustrating the influence of alternative APU particle formulations with respect to their efficacy for contaminant removal. The ability to control particle properties offers the potential to produce different nanoparticles optimized for varying contaminant types and soil conditions.     

Relations among scores on Edwards Personal Preference Schedule, California Psychological Inventory, and Strong Vocational Interest Blank for an industrial sample.

The significant intercorrelations among scores on the EPPS, the CPI, and the SVIB are reported for a group of 102 salaried employees of the 3M Company. Comparison of the CPI and EPPS scales generally shows correlations in the expected directions, and correlations between occupational interests and personality variables make "good clinical sense." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Die Verteilung von Zink zwischen Ferrit und Austenit und die Thermodynamik des Zweistoffsystems Eisen—Zink

Verfahren zur Herstellung sehr reiner Eisen-Zink-Legierungen. Ermittlung der Sättigungsgehalte an Zink im Ferrit und Austenit mit Hilfe der Mikrosonde. Berechnungen zur Beschreibung der thermodynamischen Eigenschaften des zinklegierten paramagnetischen Ferrits und des zinklegierten Austenits unter Zuhilfenahme von thermodynamischen Werten aus dem Schrifttum. Berechnung des Gleichgewichts Austenit/Ferrit, Festlegung der γ-Schleife des Zustandsschaubildes und Vergleich mit den ermittelten Werten. Berechnung der Löslichkeit der Γ-Phase im α-Eisen mit Hilfe der bereits bekannten Thermodynamik der α-Phase. Berechnung einer metastabilen Mischungslücke und deren Spinodale im Ferrit.