Longitudinal studies of immune function in cattle experimentally infected with bovine immunodeficiency-like virus and/or bovine leukemia virus

The effects of single or dual infection with bovine immunodeficiency-like virus (BIV) and/or, bovine leukemia virus (BLV) on bovine immune function were examined over a 4 year period. Holstein calves were infected with BIV (four calves), BLV (five calves), BIV and BLV (five calves), or sham inoculated (three calves). Lymphocyte blastogenesis to mitogens, seven tests of neutrophil function, and mononuclear cell subset analysis by flow cytometry (BoCD4, BoCD8, BoCD2, BoWC1, sIgM+, and monocytes) were performed at regular intervals to 49 months post-infection. These data were analyzed for main effects of each virus and interaction as a 2 x 2 factorial. BIV infected cattle had lower neutrophil antibody-dependent cell-mediated cytotoxicity and iodination responses during 2 of the 4 years post-infection (P < 0.05). BIV infection was not associated with any long-term significant changes in lymphocyte blastogenesis to mitogens or changes in mononuclear cell subset numbers in blood. There was a tendency for animals infected with BIV alone to have decreased lymphocyte blastogenic responses to mitogens, but this was not statistically significant. BLV infection caused an increase in total mononuclear cells with no dramatic shift in the relative proportions of the various subsets. Co-infection with BIV and BLV did not consistently cause a different response than either virus did individually. One BIV infected animal died of non-BLV lymphosarcoma 7 months after infection. All other animals had no unusual clinical signs. In summary, infection with BIV caused a significant, temporary decrease in neutrophil function with no consistent statistically significant alteration in lymphocyte blastogenesis or mononuclear cell numbers during the first 4 years after infection. BLV infection caused an increase in lymphocyte numbers, and there appeared to be no synergism between the viruses.     

Effect of orthographic preactivation on letter migration.

Students participated in 6 experiments on visual word or pseudoword perception. Two items (both words or both pseudowords) were presented for brief periods of time (together or separately). A prime preceded the items in 3 experiments. Without priming, more word than pseudoword letter migrations were found. With the distracter as a prime, more migrations were found overall, as many for words as for pseudowords. With the migration response as a prime, migrations could not be demonstrated. Letter "migration" also occurred when the items were not presented simultaneously, although the number of migrations decreased. The results are explained in terms of an activation model of word perception. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Origins of children's helpless and mastery achievement patterns in the family.

An exploratory study examined the origins of children's motivational patterns in the family by observing 3rd-grade children (10 helpless and 11 mastery-oriented) and their mothers performing a series of solvable and insolvable problem-solving tasks. Mothers of mastery children appeared to show sensitivity and responsiveness to their children's ability perceptions and requests for help. They also appeared to support mastery behaviors in their children by increasing task-focused teaching behaviors and maintaining high-positive affect during the insolvable puzzles. Furthermore, in the face of failures, they retrained their children's low-ability attributions and performance-goal statements, while promoting mastery or task-focused behaviors. These findings are consistent with the hypothesis that mothers of mastery children may socialize their children's achievement motivation. However, because of the small sample size and other limitations, the results should be interpreted with caution. Several directions are outlined for future research on the familial origins of helpless and mastery patterns in children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Performance of 1-10-GHz traveling wave amplifiers in 0.18-/spl mu/m CMOS

The authors present two four-stage traveling-wave amplifiers (TWA) fabricated in a 0.18-/spl mu/m CMOS process. A TWA with an internal drain bias network achieved a gain of 5 dB out to 10 GHz, and another TWA without an on-chip bias network achieved a gain of 8 dB out to 10 GHz. These are the highest frequency CMOS TWAs known to the authors.     

New formulation and plots for error probability in the pulse position modulation (PPM) photon counting satellite-to-earth channel

In digital satellite-to-earth transmission the entry of substantial undesired solar radiation into the receiver antenna is sometimes unavoidable. When the signal transmission takes the form of incoherent optical pulse position modulation (PPM) the parameters of signal and consequent intense noise can fall outside the range of routinely available classical numerical results on symbol error probability. This paper presents an alternative system for parametrization of signal and noise in the classical PPM channel, i.e. that characterized by Poisson photon arrival statistics for signal itself, the noise itself, and the signal plus noise. The resulting formulation for error probability, the scheme for probability calculation, and the simple, compact plots of error probability versus newly conceived parameters cover the entire range of signal and noise intensities, from weakest to strongest. Of course, when properly interpreted the new results agree entirely with classically available numerical results within the parametric range of the former.     

The miniwid-coater: I. design and evaluation of a temperature-controlled miniature fluid-bed pan coater

A novel miniature laboratory-scale pan coater has been developed. Small batches of 50 to 100 g of pellets, granules, large crystalls and small tablets allow the formulation development with minimal quantities of valuable drugs and new active ingredients. Although originally it is a pan coater, the core bed will be slightly fluidized by the inlet air flow due to the small dimensions of the coating pan. This allows a rapid drying and the loss of coating materials will be negligible.

A computer was used to control the core bed temperature during the coating process by varying the spraying rate of an analytical dosing pump. Additionally, the drying air temperature can be adopted. It was possible to change the parameters during the process to optimize the operation conditions within one run. The computer program described in this article provides a constant bed temperature with a precision of ± 0.3 °C.

In the MiniWiD-Coater, neutral pellets have been loaded with bisacodyl and then enteric-coated with aqueous dispersions of Eudragit L 30 D. Batch homogeneity and reproducibility were excellent. Friability of the cores and abrasion of the coat remained low. The loss of coating material during operation was always below 5 %.     

A phase I study of high-dose tamoxifen for the treatment of refractory malignant gliomas of childhood

Recent studies have indicated that the proliferation of malignant gliomas is in part dependent on excessive activation of protein kinase C (PKC)-mediated pathways. Conversely, inhibiting PKC may provide a novel approach for blocking glioma growth. The antiestrogen tamoxifen, a moderately potent PKC inhibitor, has been shown in vitro to block the proliferation of malignant glioma cell lines at concentrations several-fold higher than those typically attained during the treatment of breast cancer; such serum concentrations may be achieved with doses > 40 mg/m2 b.i.d. The safety and efficacy of these high doses for producing disease control in patients with malignant gliomas has recently been noted anecdotally, although a rigorous study of this agent has been lacking. To address this issue, we examined the safety and efficacy of high-dose tamoxifen in a series of children with malignant gliomas that had progressed after conventional therapy. An initial group was treated with 60 mg/m2 p.o. b.i.d. and a second group with 100 mg/m2 b.i.d. Steady-state serum tamoxifen and metabolite levels were measured in most patients. Toxicity with the regimen was minimal; two patients treated at the higher dose required reduction to the lower dose because of asymptomatic prolongation of the QT interval on an electrocardiogram. Although none of the patients exhibited clear-cut tumor regression, 4 of 14 patients had stabilization of previously progressive disease for at least 3 months; the longest survivor lived for 17 months after beginning tamoxifen. The moderate efficacy of this agent in otherwise end-stage disease coupled with its low toxicity and the relative ease of oral administration provides a rationale for proceeding with larger studies of this agent in patients with malignant gliomas, possibly as a means for potentiating the effects of conventional chemotherapeutic agents, which to date have shown limited efficacy in the treatment of these tumors.     

Mathematics self-efficacy and mathematics performances: The need for specificity of assessment.

In this study, 391 students were asked to provide 3 types of mathematics self-efficacy judgments: confidence to solve mathematics problems, confidence to succeed in math-related courses, and confidence to perform math-related tasks. Criterial tasks were solution of math problems and choice of math-related majors. As hypothesized, students' reported confidence to solve the problems they were later asked to solve was a more powerful predictor of that performance than was either their confidence to perform math-related tasks or to succeed in math-related courses. Similarly, confidence to succeed in math-related courses was a stronger predictor of choice of math-related majors than was either confidence to solve problems or to perform math-related tasks. Results support A. Bandura's (1986) contention that, because judgments of self-efficacy are task specific, measures of self-efficacy should be tailored to the criterial task being assessed and the domain of functioning being analyzed to increase prediction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Book reviews

Book reviewed in this article:
The Information Economy and American Cities. Matthew P. Drennan.
Transportation Networks and the Optimal Location of Human Activities: A Numerical Geography Approach. (Transport Economics, Management and Policy Series.)
Travel Behaviour: Spatial Patterns, Congestion and Modelling. E. Stern, I. Salomon, P.H.I. Bovy (eds).
Input-Output Analysis: Frontiers and Extensions. Michael L. Lahr and Erik Dietzenbacher (eds).