Bovine milk gangliosides: Changes in ceramide moiety with stage of lactation

The stage of lactation is one of the most important factors that influence milk composition. Changes in fatty acids from triacylglycerols and phospholipids have already been reported. In this study, we looked for a lactational change in the ganglioside lipid moeity since ganglioside contents and patterns vary strongly with stage of lactation. Individual gangliosides from four stages were isolated, methanolyzed to cleave the bonds between individual constituents, and derivatized for gas-liquid chromatography and gas chromatography/mass spectrometry analyses. Ceramide components, both fatty acids (as methyl esters derivatives) and long-chain bases, were identified and quantified. The results pointed to a marked change in ceramide from colostrum to milk that was characterized by a dramatic decrease in saturated and the longest-chain fatty acids as well as an increase in 18∶1 and 18∶2. The major long-chain base along lactation was a recently described structure, 3-ethoxy-15∶0 sphinganine. Other new long-chain base structures appeared in these gangliosides. All these changes suggest differences in the fluidity of the fat globule membrane, reflecting physiological variations in cows with respect to milk production.     

Reliability models based on bivariate exponential distributions

Motivated by reliability applications, we derive the exact distributions of R=X+Y and W=X/(X+Y) and the corresponding moment properties when X and Y follow five flexible bivariate exponential distributions. The expressions turn out to involve several special functions.     

A coprecipitation technique to prepare NaNbO3 and NaTaO3

A simple coprecipitation technique has been used successfully for the preparation of pure, ultrafine, single phases of NaNbO₃ (NN) and NaTaO₃ (NT). An alcoholic solution of ammonium carbonate and ammonium hydroxide was used to precipitate Na⁺ and Nb⁵⁺ (or Ta⁵⁺) cations under basic conditions as carbonate and hydroxide, respectively. On heating at 700°C, these precursors produce respective products. For comparison, both NN and NT powders were also prepared by the traditional solid state method. The phase purity and lattice parameters were studied by powder X-ray diffraction (XRD). The particle size and morphology were studied by scanning electron microscopy (SEM).     

Mixed motives and racial bias: The impact of legitimate and illegitimate criteria on decision making.

Recent high-profile court rulings addressing the influence of illegitimate information--such as race--on decision making have highlighted the difficulty of establishing whether and when discrimination has occurred. One factor complicating such efforts is that decision makers are often simultaneously influenced by racial and nonracial information. The authors examined the psychological processes underlying such mixed-motive decision making, demonstrating how legitimate information can be manipulated to justify preferences based on illegitimate factors such as race. Study 1 showed that Black candidates were favored over White candidates in hypothetical college admissions decisions, although participants justified their decisions using nonracial information, and further showed that participants' levels of prejudice predicted both which candidate was chosen and how those choices were justified. Study 2 demonstrated that these justifications were not simply strategic and post hoc but also occurred as a natural part of the process of evaluating candidates. Discussion focuses on policy and legal implications for employment discrimination, affirmative action, and courtroom proceedings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On racial diversity and group decision making: Identifying multiple effects of racial composition on jury deliberations.

This research examines the multiple effects of racial diversity on group decision making. Participants deliberated on the trial of a Black defendant as members of racially homogeneous or heterogeneous mock juries. Half of the groups were exposed to pretrial jury selection questions about racism and half were not. Deliberation analyses supported the prediction that diverse groups would exchange a wider range of information than all-White groups. This finding was not wholly attributable to the performance of Black participants, as Whites cited more case facts, made fewer errors, and were more amenable to discussion of racism when in diverse versus all-White groups. Even before discussion, Whites in diverse groups were more lenient toward the Black defendant, demonstrating that the effects of diversity do not occur solely through information exchange. The influence of jury selection questions extended previous findings that blatant racial issues at trial increase leniency toward a Black defendant. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Developing a Resource Supply Chain Planning System for Construction Projects

The high variability of construction environments results in high construction-cost variation, especially in material costs. Inadequate planning may cause material shortages that delay the project schedule or, alternatively, a substantial increase in inventory costs by producing or supplying materials earlier than they are needed at the construction site. In order to solve these problems, this paper studies steel rebar production and supply operations and establishes an optimal model that minimizes the integrated inventory cost of the supply chain. Based on the optimal model, this paper develops a decision-support system to generate a production and supply plan for a supplier and buyers of steel rebar. After utilizing the decision-support system to create the supply and production plan, this paper analyzes the results to study the influence of transaction constraints on inventory cost. This paper also discusses cases of global optimization of the inventory cost for the entire supply chain and compares them with cases of local optimization for individual members.     

Photoinduced emission and thermoluminescence in topaz

Topaz has been demonstrated to be useful for dosimetric application. This mineral exhibits a satisfactory thermoluminescent (TL) response to radiation. In previous studies we analyzed the natural topaz samples from Minas Gerais, Brazil, by TL, infrared and X-ray diffraction techniques, with the aim of obtaining an explanatory model for the process of light emission of this mineral. Thermal treatments and irradiations do not produce significant changes in the TL emission. TL spectra exhibit a broad band with a maximum TL intensity at 420 nm in all the samples. In order to better understand the physical processes involved in the light emission of the topaz, we analyzed the photoinduced fluorescence of natural (as received) and thermally treated samples in powder form. The photoinduced emission of topaz was found to be similar to that of other silicates. In the UV–visible range there are intense emission bands between 350 and 550 nm, with a maximum intensity at 435 nm. The intensities are different for each sample.     

Link-State-Based Algorithms for Dynamic Routing in All-Optical Networks with Ring Topologies

The increased usage of large bandwidth in optical networks raises the problems of efficient routing to allow these networks to deliver fast data transmission with low blocking probabilities. Due to limited optical buffering in optical switches and constraints of high switching speeds, data transmitted over optical networks must be routed without waiting queues along a path from source to destination. Moreover, in optical networks deprived of wavelength converters, it is necessary for each established path to transfer data from source to destination by using only one wavelength. To solve this NP-hard problem, many algorithms have been proposed for dynamic optical routing like Fixed-Paths Least Congested (FPLC) routing or Least Loaded Path Routing (LLR). This paper proposes two heuristic algorithms based on former algorithms to improve network throughput and reduce blocking probabilities of data transmitted in all-optical networks with regard to connection costs. We also introduce new criteria to estimate network congestion and choose better routing paths. Experimental results in ring networks show that both new algorithms achieve promising performance.     

Attentional consequences of object appearance and disappearance.

This study compared the attentional effects of object appearances (onsets) and disappearances (offsets) in moderately complex displays. Four experiments showed that onsets produce the inhibition of return (IOR) effect that has been found with simpler displays. In contrast, although offsets did produce inhibitory effects, these effects did not follow the spatial or temporal pattern of IOR. Two further experiments used a very salient object disappearance to determine whether the typical pattern for IOR could be instantiated; it was not. The results indicate that object appearances are more potent perceptual events than object disappearances. In addition, object disappearances have different attentional consequences than object appearances: Disappearances provoke earlier and spatially narrower inhibition. The results are consistent with the view that inhibition serves a functional role in increasing the efficiency of visual search processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Analysis of the level of comprehension of chemical hazard labels: a case for Zambia

We have surveyed the impact of chemical hazard label elements on four target sectors, i.e. the agricultural, industrial, transport and the consumer (the general public) sectors, in order to assess the type of reactions the respondents perceive to a given chemical label element such as symbol, hazard phrase, color, and hazard signal word. The survey revealed that the level of education, gender and/or age did not influence the respondents' perception of the extent of hazard but rather familiarity or frequency of use of the chemicals and acquaintance with chemical label elements was significant in the assessment of the extent of perceived hazard posed by a given chemical. Symbols such as the St Andrews Cross--though common--is virtually not understood by more than 80% of the respondents in all the sectors. We noted that respondents appreciate symbols they can relate to, which are flame-like, ghost-like and exert immediate impacts to respondents. Color codes have found use in the agriculture sector because of their ease to be recalled especially by the majority of illiterate farm workers. The survey revealed that red in agricultural circles is well associated with high toxicity while other colors such as yellow and blue can not clearly be associated with hazard. The word "toxic" is not used in the industry and transport sectors where the most hazard signal word is "danger". The Globally Harmonized System (GHS) classification adopted "danger" and "warning" for use as signal words. The survey revealed that effective chemical hazard symbols must not be too abstract to the client but should contain features that are known or easily comprehended.