Establishment of a flavor preference in rats: Importance of nursing and weaning experience.

In a study with 36 Sprague-Dawley pups it was found that Ss that experienced garlic flavor during 21 days of nursing (in mother's milk) and for a 5-day period after weaning drank considerably more garlic solution over 12 days of testing than did Ss nursed by water-imbibing mothers and weaned on water. Still other Ss that had garlic either during nursing or after weaning manifested intermediate garlic preferences over these same tests, though the initial intake of garlic was greater in the former condition. The durability of such preferences was demonstrated in a 2nd series of 6 daily tests given 1 mo later when the same ordering of groups recurred. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The relationship between molecular parameters and polymer distribution and the ability of a polymer to improve the resilience of cotton fabrics

Elastic properties are found to be critical parameters for polymers which improve the wrinkle resistance of cotton fabric. Those molecular factors which results in optimum recovery of a polymer film from distortion (i.e., stretching) are shown to be directly related to the ability to improve fabric wrinkle recovery. Further, those molecular factors which inhibit the tendency of a polymer to form ordered structures allow the inherent flexibility of the polymer to be utilized in storing energy of distortion. This energy is then available, if the polymer is properly distributed on the fabric, to help overcome the fabric's frictional resistance to recovery. The most advantageous distribution of polymer is one in which interfiber and interyarn elastic bridges are formed.     

Magnetic ripple diffusion and stable INTOR equilibria

Under conditions representative of ignited tokamak operation, ion energy losses are likely to be dominated by transport due to deviation from toroidal field axisymmetry. This asymmetry, termed ripple, induces several distinct physical processes, all of which lead to enhanced ion thermal conduction above the neoclassical value. The net impact of these processes on ignition dynamics is analyzed for an INTOR-like plasma by means of a 1 1/2-D transport code. The radial shift of the plasma to regions of higher ripple during plasma heating results in a substantial broadening of the window of values of ripple consistent with favorable ignition and burn characteristics and also provides some measure of automatic burn control. Because-limiting processes are also prime candidates for burn control, the profiles obtained from the transport analyses are examined for stability with respect to ideal MHD modes. The MHD-limited value increases as the plasma is heated and in fact in the burn phase approaches the value characteristic of a shape-optimized MHD equilibrium. The sensitivity of the transport and MHD results to the choice of plasma density is examined, and it is found that hot-ion mode operation is precluded for devices such as INTOR unless present estimates of both ripple losses and-limits are highly pessimistic.     

Evaluation of surface concentration of erucamide in LLDPE films

Additives are often blended into polymers to improve specific performance features of the finished film. Erucamide is a common slip agent used to reduce a film's coefficient of friction (COF), which is a good attribute for high speed packaging operations. Because such additives must migrate to the surface to be effective, this study focuses on erucamide blooming to the surface of linear low-density polyethylene (LLDPE) films. Both the surface and bulk concentrations of erucamide were measured over time to determine the equilibrium additive partitioning. The surface concentration was determined by surface washing for different time intervals and extrapolated back to a “zero” time to offset the solvent extraction of additive from the bulk film. The bulk concentration was determined by a deep microwave extraction. Initial experiments with forced aging at 60°C showed significant evaporative losses of erucamide. The final work focused on room temperature, at whcih additive evaporation was negligible. The room temperature blooming results showed that the erucamide surface and bulk concentrations reached equilibrium within 24 hours. The data also showed that erucamide surface concentration increased with initial additive loading for a fixed film thickness and with increased film thickness for a fixed additive concentration.     

A comparative study of conventional instruction and individual programed instruction in the college classroom.

The traditional college classroom teaching method of lecture and assigned readings was compared with an individual programed instructional method utilizing a programed text. 21 pairs of Ss, matched according to sex, age, intelligence test score, and hours of formal training in the biological sciences, were 1st tested upon completion of the physiological portion of an introductory psychology course. They were then retested 6 wk. later. No significant differences were found in performance on Test 1. However, the level of performance on Test 2 was significantly higher for the program-instructed group. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Pre-positioning planning for emergency response with service quality constraints

Pre-positioning of emergency supplies is a means for increasing preparedness for natural disasters. Key decisions in pre-positioning are the locations and capacities of emergency distribution centers, as well as allocations of inventories of multiple relief commodities to those distribution locations. The location and allocation decisions are complicated by uncertainty about if, or where, a natural disaster will occur. An earlier paper (Rawls and Turnquist 44:521–534, 2010) describes a stochastic mixed integer programming formulation to minimize expected costs (including penalties for unmet demand) in such a situation. This paper extends that model with additional service quality constraints. The added constraints ensure that the probability of meeting all demand is at least α, and that the demand is met with supplies whose average shipment distance is no greater than a specific limit. A case study using hurricane threats is used to illustrate the model and how the additional constraints modify the pre-positioning strategy.     

Compliant phase reduces polymerization shrinkage in dental composite resin

Commercially available dental composite resins undergo polymerization shrinkage during curing, setting up internal stress that can result in debonding at the tooth‐composite interface, tooth fracture and composite failure. Debonding can also lead to marginal leakage and recurrent decay. The presence of a compliant phase, in this case polybutadiene in aggregate form with fumed silica, is shown to reduce polymerization shrinkage in the bis‐GMA/TEGDMA resin system. The addition of a small amount of the plasticizer triphenylethylene promoted additional reduction in cure shrinkage by reducing the glass transition temperature, T_g. A trend toward reduced cure shrinkage was noted as the polybutadiene : silica ratio decreased within each molecular weight of polybutadiene tested. The optimal formulation tested was determined to be 0.25 wt. % triphenylethylene in bis‐GMA with aggregates formed from polybutadiene of molecular weight 2–3 million, in a polybutadiene : silica ratio of 0.005. Shrinkage reduction in this system was ～ 42% without loss of Knoop hardness. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2306–2310, 2005     

Improving fracture toughness of dental nanocomposites by interface engineering and micromechanics

The fracture toughness of dental nanocomposites fabricated by various methods of mixing, silanization, and loadings of nanoparticles had been characterized using fatigue-precracked compact-tension specimens. The fracture mechanisms near the crack tip were characterized using atomic force microscopy (AFM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The near-tip fracture processes in the nanocomposties were identified to involve several sequences of fracture events, including: (1) particle bridging, (2) debonding at the poles of particle/matrix interface, and (3) crack deflection around the particles. Analytical and finite-element methods were utilized to model the observed sequences of fracture events to identify the source of fracture toughness in the dental nanocomposites. Theoretical results indicated that silanization and nanoparticle loadings improved the fracture toughness of dental nanocomposites by a factor of 2-3 through a combination of enhanced interface toughness by silanization, crack deflection, as well as crack bridging. A further increase in the fracture toughness of the nanocomposites can be achieved by increasing the fracture toughness of the matrix, nanofilled particles, or the interface.     

BBN TransTalk: Robust multilingual two-way speech-to-speech translation for mobile platforms

In this paper we present a speech-to-speech (S2S) translation system called the BBN TransTalk that enables two-way communication between speakers of English and speakers who do not understand or speak English. The BBN TransTalk has been configured for several languages including Iraqi Arabic, Pashto, Dari, Farsi, Malay, Indonesian, and Levantine Arabic. We describe the key components of our system: automatic speech recognition (ASR), machine translation (MT), text-to-speech (TTS), dialog manager, and the user interface (UI). In addition, we present novel techniques for overcoming specific challenges in developing high-performing S2S systems. For ASR, we present techniques for dealing with lack of pronunciation and linguistic resources and effective modeling of ambiguity in pronunciations of words in these languages. For MT, we describe techniques for dealing with data sparsity as well as modeling context. We also present and compare different user confirmation techniques for detecting errors that can cause the dialog to drift or stall.