Material-specific lateralization of prefrontal activation during episodic encoding and retrieval

Although numerous neuroimaging studies have examined the functional neuroanatomy supporting episodic memory for verbal material, there have been few investigations of non-verbal episodic encoding and retrieval. We used fMRI to directly compare prefrontal activation elicited by verbal and non-verbal material during encoding and during retrieval. Regardless of the mnemonic operation (encoding/retrieval), inferior prefrontal activation lateralized based on material type. Verbal encoding and retrieval resulted in greater left inferior prefrontal activation, whereas non-verbal encoding and retrieval resulted in greater right inferior prefrontal activation. The similarity between inferior prefrontal activity during encoding and during retrieval indicates that these mnemonic operations depend on shared processes mediated by inferior prefrontal regions.     

The effect of temperature on the

The tensile stress-strain behavior and failure mechanisms of Ti-24Al-11Nb and a SiC/ Ti-24Al-11Nb composite with continuous SCS-6 fibers oriented parallel to the loading direction have been examined over a range of temperatures from 23 °C to 815°C in air. Failure in Ti- 24Al-11Nb occurred at strains of approximately 4 pct soon after crack initiation at low tem- peratures. Ductility increased with temperature up to a maximum of 20 pct elongation at 600 °C, as surface-initiated cracks did not propagate readily at intermediate temperatures. At higher temperatures, the onset of grain boundary and interfacial void nucleation limited ductility. Com- posite failure appeared to be controlled by fiber fracture at all temperatures; for practical en- gineering purposes, composite failure occurred at 0.8 pct strain at all temperatures. At temperatures of 425 °C and less, fiber fractures occurred at intervals along the lengths of the fibers and appeared to be cumulative, while at temperatures of 650 °C and greater, fiber fractures were only observed locally to the fracture surfaces. The decreased radial residual stresses, interfacial strengths, and matrix properties at 650 °C and 815 °C allowed the composite to unload at 0.8 pct strain, due to fiber fractures, followed by a reloading in which fibers pulled out and the matrix failed, resulting in composite failure. The decreasing residual stresses with increasing temper- ature determined from an elastic-plastic concentric cylinder model were shown to affect the stress-strain response of the composite and were consistent with the measured decreasing inter- facial shear stresses, the increased fiber pullout with temperature, and the circumferential de- bonding observed around the fibers at higher temperatures.     

The Satchel system architecture: Mobile access to documents and services

Mobile professionals require access to documents and documentrelated services, such as printing, wherever they may be. They may also wish to give documents to colleagues electronically, as easily as with paper, facetoface, and with similar security characteristics. The Satchel system provides such capabilities in the form of a mobile browser, implemented on a device that professional people would be likely to carry anyway, such as a pager or mobile phone. Printing may be performed on any Satchelenabled printer, or any fax machine. Scanning, too, may be accomplished at any Satchelenabled scanner. Access rights to individual documents may be safely distributed, without regard to document formats. Access to document services is greatly simplified by the use of context sensitivity. The system has been extensively tested and evaluated. This paper describes the architecture of the Satchel system.     

Oxidation of FeCrAlY Fibers at Low Oxygen Potentials

The oxidation of Fe-15Cr-5Al-0.3Y (wt.%) coupons and 22-μm-diameter fibers has been studied in a helium atmosphere containing ～150 ppm oxygen at temperatures of 750–950 °C. Thermogravimetric analysis was used to follow kinetics, and oxide scales were analyzed with scanning-electron microscopy, electron-microprobe analysis, and photostimulated luminescence. The observed kinetics behavior of the coupons and fibers is attributed to effects of both transitional aluminas and aluminum depletion in the alloy. Distinct differences are observed with the fibers as compared to the coupons at 900 and 950 °C, but similar behavior is observed at 850 °C. Pre-oxidation treatments of the fibers at 1,100 °C in air formed a thin layer of α-Al₂O₃ and slowed oxidation dramatically at 850 °C. The fibers showed aluminum depletion and formed mixed alumina-chromia scales, which appeared adherent and protective.     

Observed communication in couples two years after integrative and traditional behavioral couple therapy: Outcome and link with five-year follow-up.

Objective: To examine changes in observed communication after therapy termination in distressed couples from a randomized clinical trial. Method: A total of 134 distressed couples were randomly assigned to either traditional behavioral couple therapy (TBCT; Jacobson & Margolin, 1979) or integrative behavioral couple therapy (IBCT; Jacobson & Christensen, 1998). Videotaped samples of each couple's interactions were coded from pre-therapy, post-therapy, and 2-year follow-up assessments. At these 3 time points, each partner chose 1 current relationship problem to discuss. Relationship satisfaction was assessed at 2-year follow-up, and clinically significant treatment response and marital status were assessed 5 years after treatment. Results: Observed negativity and withdrawal decreased from therapy termination through the 2-year follow-up as expected, but problem solving did not change, and observed positivity decreased. IBCT produced superior changes from post-therapy to the 2-year follow-up assessment compared with TBCT. Post-therapy levels and changes in communication over follow-up were associated with wife satisfaction at 2-year follow-up; only post-therapy to 2-year follow-up changes in communication were associated with husband satisfaction at 2-year follow-up. Post-therapy levels of problem solving and changes in wives' positivity from pre-therapy to post-therapy were associated with 5-year relationship outcomes. We found some counterintuitive results with positivity, but they were no longer significant after controlling for withdrawal. Conclusions: We found support for improvements in observed communication following treatment termination, with IBCT demonstrating greater maintenance of communication improvement over follow-up. We found limited evidence of associations between communication and relationship outcomes at 5-year follow-up. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Chemical comparison of a mexican soybean variety with a us variety

The proximate analysis, protein, amino acid, and fatty acid composition and flavor evaluation of mature seeds of a commercial variety soybeans grown in Mexico and of one grown in the United States were compared. The study indicated very little difference between the two varieties.     

Alteration in cell kinetics in control B6C3F1 mice infected with Helicobacter hepaticus

The discovery of Helicobacter hepaticus infection, H. hepaticus hepatitis, and increased incidence of liver tumors in control males from several recent National Toxicology Program B6C3F1 mouse carcinogenicity bioassays raised questions regarding the suitability of these bioassays for hazard identification. The purpose of this study was to determine if changes in cell proliferation and death at terminal sacrifice might be linked to the increased liver tumor incidences among control males. In control males, enhanced rates of hepatocyte proliferation, as assessed by immunostaining for proliferating cell nuclear antigen (PCNA), and apoptosis, as assessed from hematoxylin and eosin- and TUNEL-stained preparations, were seen in 3 bioassays with H. hepaticus hepatitis. One bioassay with H. hepaticus infection without attendant hepatitis and one bioassay without H. hepaticus or hepatitis did not have elevated rates of hepatocyte proliferation or apoptosis. There was no significant effect on PCNA cell proliferation indices or apoptosis in females. The present findings are indicative of a clear association between the presence of H. hepaticus infection with attendant hepatitis, increased cell proliferation and apoptosis, and increased incidences of hepatocellular neoplasia in males but not in females. Thus, the interpretation of liver tumor responses in H. hepaticus-infected studies is considered to be confounded in male mice. The lack of enhanced cell proliferation or hepatocellular neoplasia in control females suggests that bioassay results from females are valid for hazard identification. Furthermore, the absence of enhanced cell proliferation in lungs and kidneys of male and females suggests that neoplastic effects at these sites are not exacerbated by H. hepaticus infection.     

Effects of the carcinogen, acrylonitrile, on forestomach cell proliferation and apoptosis in the rat: comparison with methacrylonitrile

Acrylonitrile (AN) and methacrylonitrile (MAN) are two major industrial nitriles used in the production of plastics and acrylic fibers. Whereas AN is a potent acute toxin and carcinogenic in rats, little is known regarding MAN. Current work is part of an overall effort designed to assess the potential toxicity/carcinogenicity of MAN. The present study compares the ability of the two chemicals to induce epithelial proliferation and apoptosis in the forestomach (FS; a target of AN carcinogenicity), liver and glandular stomach (non-targets of AN carcinogenicity) of male F344 rats. AN was administered to rats daily, by gavage, for 6 weeks, at 0.43 and 0.22 mmol/kg. MAN was administered at 0.87 and 0.43 mmol/kg. Both AN and MAN induced a dose-dependent increase in epithelial cell proliferation in the FS of male F344 rats as determined by bromodeoxyuridine (BrdU) incorporation into DNA. In contrast, AN, but not MAN caused a dose-dependent increase in the thickness of the forestomach squamous mucosa. This increased thickness (hyperplasia) was reflected by an increase in the number of total epithelial cells per unit length of mucosa. At doses of AN and MAN which induced a 2.3-fold increase in BrdU incorporation, apoptosis was 5- and 18-fold greater than controls, respectively. Although both MAN and AN caused a similar increase in cell proliferation, the relatively more prominent increase in the apoptotic index of the squamous epithelium of rats exposed to MAN may explain the lack of a detectable increase in the thickness of the mucosa compared to that seen with AN. The disruption of the balance between FS mucosal cell proliferation and apoptosis in favor of a net increase in the number of FS epithelial cells per unit length may contribute to the carcinogenicity of AN. In conclusion, present work demonstrated that AN selectively induced a net enhancement in FS cell proliferation, a site of its carcinogenicity. On the other hand, MAN-induced FS cell proliferation was associated with a parallel increase in apoptosis. The relatively greater increase in apoptosis by MAN may have compensated for the increase in FS mucosal cell proliferation and the lack of observable change in the FS thickness.