Genetic control of immunity to Heligmosomoides polygyrus: presentation of promiscuous antigens to parasite-specific T cell hybridomas

The role of MHC class II in the presentation of Heligmosomoides polygyrus antigens has been investigated, using a number of T cell hybridomas produced in A and E positive and negative mice. By using fixed and irradiated antigen presenting cells (APC), further evidence has emerged, to support earlier data, that there can be differential processing requirements during the presentation of H. polygyrus antigens by A and E molecules. In concordance with these earlier observations, this work provides further evidence than individual T cells can respond to antigen when presented by more than one MHC molecule. Previously, this evidence has been restricted to individual MHC molecules of the same haplotype, but these data show that H. polygyrus produces antigens which can be presented by both syngeneic and allogeneic MHC molecules. These antigens do not appear to be synonymous with the previously described H. polygyrus superantigen, as presentation is restricted to specific MHC haplotypes. It is proposed that H. polygyrus may produce these antigenic molecules as part of its strategy to manipulate the host immune system.     

What's the use of being happy? Mood states, useful objects, and repetition priming effects.

Two experiments involving 99 undergraduate participants sought to examine the influence of mood states on encoding speed within lexical decision and pronunciation tasks. Mood states were measured naturalistically in Experiment 1 and manipulated in Experiment 2. Stimuli consisted of nouns representing useful (e.g., food) and nonuseful (e.g., lint) objects. Mood states had no implications for initial encoding speed. However, when the same words were presented a 2nd time (i.e., repeated), happy individuals displayed a tendency to encode useful words faster than nonuseful ones. Thus, mood states influenced repetition priming on the basis of stimulus valence. The authors propose that happiness sensitizes individuals to useful or rewarding objects, which in turn creates a stronger memory trace for such stimuli in the future. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Numerical Modeling of Silicon Photodiodes for High-Accuracy Applications Part I. Simulation Programs

The suitability of the semiconductor-device modeling program PC-1D for high-accuracy simulation of silicon photodiodes is discussed. A set of user interface programs optimized to support high-accuracy batch-mode operation of PC-1D for modeling the internal quantum efficiency of photodiodes is also described. The optimization includes correction for the dark current under reverse- and forward-bias conditions before calculating the quantum efficiency, and easy access to the highest numerical accuracy available from PC-1D, neither of which is conveniently available with PC-1D’s standard user interface.     

Malignant salivary gland tumors

Records of 60 patients with primary salivary gland tumors were retrospectively analyzed. Most were European Jews, 60% were males, and the average age was 57 years. The parotid gland was the most frequent site of origin (76%). The main presenting symptom was painless swelling. Pain or facial palsy were rare and associated with poor prognoses. The most common types were mucoepidermoid, adenocystic, adenocarcinoma and malignant, mixed carcinomas (in descending order of frequency). Squamous cell carcinoma was the most prevalent histologic type. Most patients presented at an advanced stage. Treatment was mainly surgical and postoperative radiotherapy was given to those with advanced disease. Most recurrences occurred within 3 years of initial treatment. Actuarial 10-year survival for all patients was 40%. Superior survival rates were achieved in women, probably due to less aggressive malignancies. Low grade mucoepidermoid carcinoma had a favorable prognosis, whereas anaplastic carcinoma had the worst. Other significant prognostic factors included stage and grade of disease.     

Continuity and change: past experience as adaptive repertoire in occupational adaptation

Narratives are gaining recognition as important ways occupational therapists and other clinicians can think about the life stories of clients. The purpose of this article is to examine a conceptualization of how changes from one chapter to another occur in life stories, using the metaphor of an adaptive repertoire, and to consider how this notion can be useful in helping clients maintain continuity and a coherent life story in times of change. Three premises based on the concept of adaptation address (a) configurations of occupational forms embedded in particular local worlds, (b) cumulative development of an adaptive repertoire that allows one to perform both competently and appropriately, and (c) adaptive transitions and application of one's repertoire to new circumstances. Implications for research and clinical practice in occupational therapy also are examined.     

Computational study of packing a collagen-like molecule: quasi-hexagonal vs "Smith" collagen microfibril model

The lateral packing of a collagen-like molecule, CH3CO-(Gly-L-Pro-L-Pro)4-NHCH3, has been examined by energy minimization with the ECEPP/3 force field. Two current packing models, the Smith collagen microfibril twisted equilateral pentagonal model and the quasi-hexagonal packing model, have been extensively investigated. In treating the Smith microfibril model, energy minimization was carried out on various conformations including those with the symmetry of equivalent packing, i.e., in which the triple helices were arranged equivalently with respect to each other. Both models are based on the experimental observation of the characteristic axial periodicity, D = 67 nm, of light and dark bands, indicating that, if any superstructure exists, it should consist of five triple helices. The quasi-hexagonal packing structure is found to be energetically more favorable than the Smith microfibril model by as much as 31.2 kcal/mol of five triple helices. This is because the quasi-hexagonal packing geometry provides more nonbonded interaction possibilities between triple helices than does the Smith microfibril geometry. Our results are consistent with recent x-ray studies with synthetic collagen-like molecules and rat tail tendon, in which the data were interpreted as being consistent with either a quasi-hexagonal or a square-triangular structure.     

A suggested method of estimation for spatial interdependent models with autocorrelated errors,and an application to a county expenditure model

The purpose of this paper is two-fold. First, we describe an estimation procedure that should be useful for spatial models which contain interactions between the dependent variables and autocorrelated error terms. Second, we apply that procedure to a spatial model relating to county police expenditures. Our estimation procedure does not require the specification of the error distribution, and its computational burden is modest. Large sample results are given.