Characteristics of Milk Powders Produced by Spray Freeze Drying

Skim and whole milk powders were manufactured at lab scale by spray freeze drying (SFD), using liquid nitrogen as the cryogen. The polydispersity of droplet/particle sizes was limited using an encapsulator nozzle to atomize the feed. Particle morphology was examined using a scanning electron microscope. Samples were compared with equivalent spray-dried powders in tests of wettability and dissolution in water. The spray freeze-dried powders were found to be highly porous, with a uniform structure of pores throughout the entire particles. When tested in water, SFD skim milk powders wetted roughly three times as fast as industrially spray-dried agglomerated skim milk powders and were observed to dissolve rapidly by breaking down into smaller particles.     

Developing competency-based methods for near-real-time air combat problem solving assessment

Air combat scenarios present unique problems where the solution is not obvious. An advanced networked simulation environment can be used to train high-level cognitive air combat skills such as problem solving. A problem in the development of principled and construct oriented assessment is related to determining the level of specificity of the assessment. We present a detailed discussion of the definition of critical competencies associated with combat mission problem solving performance, and we describe our approach to develop and implement an embedded performance assessment system that maps outcomes to these competencies. Finally, we discuss the implications for our approach for comprehensive assessment and discuss our goals for an evaluation of the competency-based approach to assessment.     

"Learning myopia: An adaptive recency effect in category learning": Correction to Jones and Sieck (2003).

Reports an error in "Learning myopia: An adaptive recency effect in category learning" by Matt Jones and Winston R. Sieck (Journal of Experimental Psychology: Learning, Memory, and Cognition, 2003[Jul], Vol 29[4], 626-640). On page 633, Table 2, the values in columns (T, P) and (P, T) in the dual condition row incorrectly read .10 and .90, respectively. The correct values are .90 and .10, respectively. (The following abstract of the original article appeared in record 2003-06626-013.) Recency effects (REs) have been well established in memory and probability learning paradigms but have received little attention in category learning research. Extant categorization models predict REs to be unaffected by learning, whereas a functional interpretation of REs, suggested by results in other domains, predicts that people are able to learn sequential dependencies and incorporate this information into their responses. These contrasting predictions were tested in 2 experiments involving a classification task in which outcome sequences were autocorrelated. Experiment 1 showed that reliance on recent outcomes adapts to the structure of the task, in contrast to models' predictions. Experiment 2 provided constraints on how sequential information is learned and suggested possible extensions to current models to account for this learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Analysis of Indentation Crack as a Wedge-Loaded Half-Penny Crack

Surface cracks produced by indentation with a Vickers indenter were modeled as half-penny cracks extended by symmetric disk-shaped wedges. The wedge diameter was assumed to be equal to the hemispherical plastic zone size, and the wedge thickness was calculated by equating the wedge volume to the hardness-impression volume. The resulting equilibrium relation between the indentation load and the radius of the half-penny crack is in good quantitative agreement with similar relations obtained from fracture toughness calibration.     

A simplified method for analyzing mold filling dynamics. Part II: Extensions and comparisons with experiment

A dimensional analysis based on four parameters has been developed previously to predict injection pressure; clamp force, and bulk temperature for the injection molding of amorphous materials in center-gated disk-shaped cavities. In this paper geometric and semicrystalline-materials approximations are introduced and tested for extending the previous analysis to include multigated thin cavities and semicrystalline materials. The combination of these approximations and the previous analysis, known hereafter as the Radial Flow Method (RFM), greatly simplifies the analysis of mold filling. The geometric approximation, which is based on a simple model for the axial stress distribution in the cavity, is shown to give reasonable predictions when compared with experimental data and a numerical two-directional flow simulation for the filling of an off-center-gated rectangular cavity with acrylonitrilebutadiene-styrene copolymer (ABS). The semicrystallinematerials approximation, in which heat capacity and viscosity changes during crystallization are neglected, is shown to give good agreement with experimental data for the filling of a center-gated disk-shaped cavity with polypropylene. As an illustration, the Radial Flow Method is used to analyze the molding of a large, thin-wall automobile interior trim panel. The inlet melt temperature, mold-wall temperature, part thickness, injection rate, viscosity and gate locations are varied in a series of calculations to determine the relative effectiveness of these variables in lowering the injection pressure and Clamp force. The results obtained with the Radial Flow Method are in good agreement with those obtained by a finiteelement simulation of two-directional flow.     

Developmental variations in plasma leptin,leptin soluble receptor and their molar ratio in healthy infants

Background  

Leptin and its soluble receptor (sOB-R) are important to regulation of body composition but there are no data on the developmental variations in these plasma variables and their relationship with body composition measurements,     

Mandibular gland components of european and africanized honey bee queens (Apis mellifera L.)

The composition of the five-component honey bee queen mandibular gland pheromone (QMP) of mated European honey bee queens was compared to those of virgin and drone-laying (i.e., laying only haploid unfertilized eggs that develop into males), European queens and Africanized mated queens. QMP of mated European queens showed significantly greater quantities of individual components than all queen types compared, except for a significantly greater quantity of 9-hydroxy-(E)-2-decenoic acid (9-HDA) found in Africanized queens. Glands of European drone-laying queens contained quantities intermediate between virgin and mated queens, reflecting their intermediate reproductive state and age. QMP ontogeny shifts from a high proportion of 9-keto-(E)-2-decenoic acid (ODA) in young unmated queens to roughly equal proportions of ODA and 9-HDA in mated queens. A biosynthetic shift occurs after mating that results in a greater proportion of 9-HDA, methylp-hydroxybenzoate (HOB), and 4-hydroxy-3-methoxyphenylethanol (HVA) production, accompanied by a decreased proportion of ODA. Africanized QMP proportions of ODA and 9-HDA were significantly different from European queens. A quantitative definition of a queen equivalent of QMP is proposed for the various queen types, and a standard queen equivalent for mated European honeybee queen mandibular gland pheromone is adopted as 200µg ODA, 80µg 9-HDA, 20µg HOB, and 2 µg HVA.     

The business value of information technology as measured by technical efficiency: Evidence from country-level data

The value of information technology (IT) in a business production process has long been a debatable issue. Explanation of the so-called “productivity paradox” has been one of the central topics in this arena. Much work has focused on firm-level analyses. This paper investigates IT contribution at a country level, using production theory in microeconomics. It negates the relationship between IT value and productivity based on grouping of countries, when the individual analytical method is applied and technical efficiency is used as the performance criterion. Findings obtained by applying stochastic production frontiers to a comprehensive country-level panel data set suggest that the IT contributions, as determined by the increase or decrease in the technical efficiency, to individual countries differ in magnitude from a production frontier to another, but are robust. It also shows that IT spending does not necessarily improve technical efficiencies of individual countries, regardless of whether they are developed or developing countries, and that given technological changes, the so-called productivity paradox may exist in a country, no matter whether it is a developed or developing nation. Finally, the significant implications of the findings are presented.     

Dual wakeup design for wireless sensor networks

Energy is often identified as the single most important resource in wireless battery-powered sensor networks. While current wakeup schemes in the literature promise to conserve energy in such networks, they apply several assumptions that may not be always true. First, all applications are assumed to require sensing coverage and network connectivity continuously; Second, a random dense deployment of sensors is always assumed possible; And third, the sensing ranges can be easily modeled by some sensing circles. In this paper, we show that these assumptions are not always valid, and propose sensor node wakeup schemes based on combinatorics block design to address energy-related issues when common assumptions fail. Another distinguishing feature of our work is also the proposal of a dual wakeup design for sensing and communications as these are two very different tasks. Finally, we verified our proposed schemes with simulations and experiments.