Regulation of fecal bile acid excretion in male golden Syrian hamsters fed a cereal-based diet with and without added cholesterol

The objective of these studies was to investigate the comparative physiology and regulation of bile acid metabolism in the male Golden Syrian hamster by measuring the rate of fecal bile acid excretion and bile acid pool size in animals fed a cereal-based diet either alone, or with added cholesterol or cholestyramine. In group-housed hamsters fed only the plain diet fecal bile acid excretion in animals at 6, 10, and 15 weeks of age averaged 11.0, 8.0, and 6.9 mumol/d per 100 g body weight (bw), respectively. Pool size, measured by subtracting from the total amount of bile acid washed out over 12 hours of biliary diversion the amount of bile acid excreted in the stools over the same period, equalled 17.8 mumol/100 g bw in 15-week-old hamsters fed the plain diet. Hence, under basal conditions, these animals turned over about 38% of their bile acid pool daily. In hamsters fed a diet with 3% cholestyramine for 18 days, fecal bile acid excretion averaged 20.6 mumol/d per 100 g bw, and the pool size contracted to 5.8 mumol/100 g bw. In matching animals fed a diet containing 0.12% cholesterol for 30 days, hepatic cholesterol levels increased from 1.9 +/- 0.1 to 12.6 +/- 0.7 mg/g, fecal bile acid excretion increased marginally from 5.8 to 8.0 mumol/day per 100 g bw, while pool size was unchanged (16.6 mumol/100 g bw). When the cholesterol content of the diet was raised to 1.0%, hepatic cholesterol levels reached 66.5 +/- 2.6 mg/g, but bile acid excretion remained at 8 mumol/d per 100 g bw. These data define some of the basal features of bile acid metabolism in the hamster, and substantiate the view that the marked cholesterolemic response of this species may relate partly to a limited ability to convert dietary cholesterol to bile acid.     

Three-wavelength electronic speckle pattern interferometry with the Fourier-transform method for simultaneous measurement of microstructure-scale deformations in three dimensions

We present the simultaneous measurement of three-dimensional deformations by electronic speckle pattern interferometry using five object beams and three colors. Each color, corresponding to an orthogonal direction of displacement, is separated through dichroic filtering before being recorded by a separate CCD camera. Carrier fringes are introduced by tilting the beam path in one arm of each of the three interferometers. The measured deformation modulates these carrier fringes and is extracted using the Fourier-transform method to achieve high displacement sensitivity. The field of view is on the order of a millimeter, making the system suitable for study of microstructural deformations. We compare experimental results with calculated values to validate out-of-plane and in-plane deformation measurements and demonstrate sensitivity on the order of 10 nm.     

Evaluating renewable portfolio standards and carbon cap scenarios in the U.S. electric sector

This report examines the impact of renewable portfolio standards (RPS) and cap-and-trade policy options on the U.S. electricity sector. The analysis uses the National Renewable Energy Laboratory's Regional Energy Deployment System (ReEDS) model that simulates the least-cost expansion of electricity generation capacity and transmission in the U.S. to examine the impact of a variety of emissions caps—and RPS scenarios both individually and combined. The generation mix, carbon emissions, and electricity price are examined for various policy combinations simulated in the modeling.     

Infants' differential social responses to attractive and unattractive faces.

Two studies were conducted to examine infants' social responses to attractive and unattractive faces. In Study 1, 60 12-month-olds interacted with a stranger who wore a professionally constructed attractive or unattractive mask. The infants showed more positive affective tone, less withdrawal, and more play involvement with the stranger in the attractive condition. In Study 2, 43 12-month-olds played with an attractive and an unattractive doll. The infants played significantly longer with the attractive doll. These results extend and amplify earlier findings showing that young infants exhibit visual preferences for attractive over unattractive faces. Both visual and behavioral preferences for attractiveness are evidently exhibited much earlier in life than was previously supposed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Modeling viscoelastic secondary flows in three‐dimensional noncircular ducts

As process capabilities become more advanced, the need to predict flow phenomena at a smaller scale increases significantly. Viscoelastic secondary flows in square ducts were simulated using a finite volume approach. Single mode and multimode Giesekus and Phan‐Thien Tanner (PTT) models were implemented and were able to reproduce full three‐dimensional (3D) flow through a square duct. Results for low density polyethylene (LDPE), polystyrene, and polycarbonate are all in agreement with experiments [Dooley, Viscoelastic flow effects in multilayer polymer coextrusion, PhD Thesis, Technische Universiteit Eindhoven (2002)] as well as numerical results using a finite element method (FEM) and a meshless radial function method (RFM), [Lopez et al., SPE ANTEC Tech. Pap. (2010)]. The mathematical model presented here has shown the potential to model full 3D flow in more complex geometries. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers     

Predictors of work adjustment in bipolar I patients: A naturalistic longitudinal follow-up.

This study explored the clinical and psychosocial predictors of work adjustment in 52 Bipolar I patients over a 2-year longitudinal period and examined associations between work functioning and social relationships, personality features, stressful life events, and clinical variables. Analyses indicated that psychosocial variables (personality disorder symptoms and social functioning) added significantly to prediction of work functioning after clinical variables were entered. Stressful life events were not associated with work adjustment. Overall, presence of a good quality supportive relationship was the strongest unique predictor of work. The results highlight the need to study functional outcomes in patients, especially because they appear only modestly associated with clinical status. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Brain activation while thinking about the self from another person’s perspective after traumatic brain injury in adolescents.

Deficits in self awareness and taking the perspective of others are often observed following traumatic brain injury (TBI). Nine adolescents (ages 12–19 years) who had sustained moderate to severe TBI after an average interval of 2.6 years and nine typically developing (TD) adolescents underwent functional MRI (fMRI) while performing a perspective taking task (D’Argembeau et al., 2007). Participants made trait attributions either from their own perspective or from that of the significant other. The groups did not differ in reaction time or on a consistency criterion. When thinking of the self from a third-person perspective, adolescents with TBI demonstrated greater activation in posterior brain regions implicated in social cognition, the left lingual gyrus (BA 18) and posterior cingulate (BA 31), extending into neighboring regions not generally associated with social cognition, that is, cuneus (BA 31) and parahippocampal gyrus, relative to TD adolescents. We postulate that adolescents with moderate to severe TBI recruited alternative neural pathways during perspective-taking because traumatic axonal injury disrupted their fronto-parietal networks mediating social cognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)