CAPPING FOR COMPRESSION SPECIMENS1

Compressive strength tests have been made on tile capped with unretarded gypsum with neat Portland cement, with a mixture of three parts by volume of Portland cement to one part of unretarded gypsum and on tile whose bearings were ground. The tile whose bearings were ground gave the highest strengths. The interpretation of the results was based on the workability and yielding of the cap and on the influence of the bearing block. As it is impossible to grind the bearings of all types of tile, a cap of three parts of Portland cement to one part of unretarded gypsum is advocated as giving the highest and most consistent results.     

Modeling and Managing State in Distributed Systems: The Role of OGSI and WSRF

We often encounter in distributed systems the need to model, access, and manage state. This state may be, for example, data in a purchase order, service level agreements representing resource availability, or the current load on a computer. We introduce two closely related approaches to modeling and manipulating state within a Web services (WS) framework: the Open Grid Services Infrastructure (OGSI) and WS-Resource Framework (WSRF). Both approaches define conventions on the use of the Web service definition language schema that enable the modeling and management of state. OGSI introduces the idea of a stateful Web service and defines approaches for creating, naming, and managing the lifetime of instances of services; for declaring and inspecting service state data; for asynchronous notification of service state change; for representing and managing collections of service instances; and for common handling of service invocation faults. WSRF refactors and evolves OGSI to exploit new Web services standards, specifically WS-addressing, and to respond to early implementation and application experiences. WSRF retains essentially all of the functional capabilities present in OGSI, while changing some syntax (e.g., to exploit WS-addressing) and also adopting a different terminology in its presentation. In addition, WSRF partitions OGSI functionality into five distinct composable specifications. We explain the relationship between OGSI and WSRF and the related WS-notification specifications, explain the common requirements that both address, and compare and contrast the approaches taken to the realization of those requirements.     

SALT GLAZES FOR STRUCTURAL BUILDING UNITS*

The conditions necessary for the formation of a clear, transparent salt glaze on structural building units are described. Laboratory trials, which were made under these conditions or slight modifications of them, were studied by means of enlarged photographs of the surfaces and thin sections of the glazes. These pictures illustrate the process of formation of the glaze and show that glazes more than 0.001 in. thick are susceptible to crazing. Salt glazes usually are formed from 0.003 to 0.004 in. thick in order to obtain a smooth brilliant glaze, but such glazes craze badly. Much better glazes may be obtained with only a sufficient number of saltings to give a glaze thickness of approximately 0.001 in., followed by a maturing or smoothing treatment in which the salting temperature is held for some time, or borax is used during the latter part of the salting and (or) the early part of the cooling period.     

The effects of encoding task on age-related differences in the functional neuroanatomy of face memory.

Age-related differences in brain activity mediating face recognition were examined using positron emission tomography. Participants encoded faces using a pleasant-unpleasant judgement, a right-left orientation task, and intentional learning. Scans also were obtained during recognition. Both young and old groups showed significant effects of encoding task on recognition accuracy, but older adults showed reduced accuracy overall. Increased brain activity in older adults was similar to that seen in young adults during conditions associated with deeper processing, but was reduced during the shallow encoding and recognition conditions. Differential correlations of brain activity and behavior were found that suggest older adults use unique neural systems to facilitate face memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of Processing on Release from an Inert, Heterogeneous Matrix

Matrixes containing 40% ephedrine hydrochloride and hydrogenated castor oil are prepared by two processes: (a) compression of a physical mixture and (b) compression of a congealed melt. The release from the melt matrix is slower than from the matrix prepared by compression of a physical mixture. applied pressure on the release profile is studied. For matrixes prepared by both processes as the applied pressure is increased, the release rate is slower; however, this effect is more pronounced for the physical mixture matrix. The effect of comminution of the medicinal compound on release profile is considered. mixture the fastest release occurs from the finer particles suggesting a boundary layer diffusion. In matrixes produced by the melt process as the particle size is decreased, the release is slowed presumably because of an increased tortuosity and more intimate contact between the ephedrine hydrochloride and the hydrogenated castor oil, which produces mass transfer by matrix diffusion.     

Type of bacterial starter culture,aging and fermentation effects on some characteristics of inoculated beef sausages

Beef sausage mixes were inoculated with either Pediococcus acidilactici with Staphylococcus xylosus or P. acidilactici with S. carnosus, subdivided and then held for 0, 24, 48 or 72 h at 8–10 °C prior to fermentation. After aging (pre-fermentation holding), the mixes were fermented for 16 h ending at 41 °C. Moisture, protein and fat contents of all sausage mixes did not differ due to holding effects over all starter cultures. The pH of mixes followed the same pattern for all mixes, declining (p < 0.05) from approximately 5.8 to pH 5.2–5.3 at 72 h aging and to 4.4–4.5 after fermentation. Total acidity of the mixes followed an inverse pattern to pH, increasing (p < 0.05) after fermentation although there was no effect due to type of starter culture. Aging had no effect on nonprotein nitrogen (NPN) content as ΔNPN among all cultures. After fermentation, however, sausages held 72 h and inoculated with S. carnosus had higher NPN contents compared to P. acidilactici alone (p < 0.05) and with S. xylosus (p < 0.10). The same effects of starter cultures on changes in total amino acid concentration were observed. Concentrations of individual amino acids showed increases depending on pre-fermentation aging period (0 h versus 72 h) followed by fermentation.     

Surface changes in polyhydroxyalkanoate films during biodegradation and biofouling

BACKGROUND: Despite the recognition that microbial biofilms play a role in environmental degradation of bioplastics, few studies investigate the relationship between bioplastic biodegradation and microbial colonisation. We have developed protocols based on a combination of confocal laser scanning microscopy and contact angle goniometry to qualitatively and quantitatively map surface changes due to biofilm formation and biopolymer degradation of solvent cast poly(3‐hydroxyalkanoate) films in an accelerated in vitro biodegradation system. RESULTS: A significant regression relationship between biofilm formation and polymer biodegradation (R² = 0.96) was primarily conducted by cells loosely attached to the film surfaces (R² = 0.95), rather than the strongly attached biofilm (R² = 0.78). During biodegradation the surface rugosity of poly(3‐hydroxybutyrate) and poly[(3‐hydroxybutyrate)‐co‐(3‐hydroxyvalerate)] increased by factors of 1.5 and 1.76, respectively. In contrast, poly(3‐hydroxyoctanoate) films showed little microbial attachment, negligible weight loss and insignificant changes in surface rugosity. CONCLUSION: A statistically significant link is established between polymer weight loss and biofilm formation. Our results suggest that this degradation is primarily conducted by cells loosely attached to the polymer rather than those strongly attached. Biofilm formation and its type are dependent upon numerous factors; the flat undifferentiated biofilms observed in this study produce a gradual increase in surface rugosity, observed as an increase in waviness. Copyright © 2008 Society of Chemical Industry     

Effects of sociometric testing on children's behavior and loneliness in school.

Examined the effects of a positive and negative peer nomination sociometric measure on children's (a) interactions with peers in general, (b) interactions with preferred and nonpreferred playmates, and (c) ratings of mood and of loneliness in school. Twenty-three 5th graders completed either a peer nomination sociometric or a control task (nominating preferred and nonpreferred school subjects). Before and after the nomination task, observers assessed the affective quality (positive, neutral, or negative) of subjects' peer interactions, and children completed mood and loneliness questionnaires. The procedures were subsequently replicated by administering the sociometric task to the control subjects. Analyses revealed no differences between the peer and control nomination task groups on any of the dependent variables measured. Analyses of pre–post differences provided no evidence of negative effects, suggesting that the risk to elementary-school-age children of completing such a sociometric measure, provided certain procedural guidelines are followed, may be minimal. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dynamical noise in single-mode distributed feedback fiber lasers

The dynamics of erbium distributed feedback fiber lasers close to steady state is analyzed taking into account spatial hole burning and the nonuniform modefield distribution. A set of linearized equations is derived and used to obtain theoretical amplitude and frequency noise spectra for spontaneous emission noise and generic pump power noise. Analytic formula for important laser characteristics including pump slope efficiency and relaxation oscillation frequency are also obtained. It is found that the spatial distribution of the laser mode plays and important role in determining the output characteristics of the laser.