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The authors tested the predictions of a game theory model of plagiarism, using a test population of student papers submitted to an online plagiarism detection program, over five semesters in a non-majors biology course with multiple sections and high enrollment. Consistent with the model, as the probability of detection and the penalty if caught increased, plagiarism rates dropped, although the latter had a smaller effect. The percentage of plagiarized papers decreased from almost 30% to less than 6% between semesters, as more students became aware that the entire course utilizes a plagiarism detection program and penalizes students who are caught plagiarizing. (Contains 1 table and 5 figures.)

Humans are notoriously resistant to changing their longstanding beliefs and often act defensively when they encounter individuals holding divergent beliefs. We introduce a meaning-based approach to humility (e.g., reduced defensiveness) [...]

Author(s): Evelynn Vergauwen[sup.1] , Anne-Marie Vanbinst[sup.2] , Carola Brussaard[sup.2] , Peter Janssens[sup.3] , Dieter De Clerck[sup.3] , Michel Van Lint[sup.4] , Anne C. Houtman[sup.4] , Olaf Michel[sup.5] , Kathelijn Keymolen[sup.6] [...], Background Patients with hereditary tumor syndromes undergo periodical magnetic resonance imaging (MRI) screening with Gadolinium contrast. Gadolinium accumulation has recently been described in the central nervous system after repeated administrations. The prevalence and rate of accumulation in different subgroups of patients are unknown. Neither are the mechanism nor clinical impact. This may cause uncertainty about the screening. To explore the prevalence and rate of Gadolinium accumulation in different subgroups, we retrospectively analyzed MRIs of patients with von Hippel-Lindau disease (VHL) and Tuberous Sclerosis Complex (TSC). Methods We determined the prevalence and rate of accumulation in the dentate nucleus and globus pallidus on unenhanced T1-weighted MRI from VHL and TSC patients. We compared the signal intensities of these regions to the signal intensity of the pons. We evaluated the impact of number of MRIs, kidney function and liver function on Gadolinium accumulation. Results Twenty eight VHL patients and 24 TSC patients were included. The prevalence of accumulation in the dentate nucleus and globus pallidus increased linearly according to number of Gadolinium enhanced MRIs and was higher in the VHL group (100%). A significant linear correlation between number of MRIs and increased signal intensity was observed in the VHL group. Conclusions Gadolinium accumulation occurs in almost all patients undergoing contrast MRI screening after >5 MRIs. We advocate a screening protocol for patients with hereditary tumor syndromes that minimizes the Gadolinium dose. This can be accomplished by using a single administration to simultaneously screen for brain, spine and/or abdominal lesions, using an MRI protocol focused on either VHL- or TSC-specific lesions. Higher prevalence and rate of accumulation in VHL patients may be explained by the typical vascular leakage accompanying central nervous system hemangioblastomas. Keywords: Von Hippel-Lindau disease, Tuberous Sclerosis Complex, Gadolinium accumulation, MRI screening, Familial tumor syndromes

An investigation is conducted into the testosterone levels in male dark-eyed juncos, which have been observed to peak at an early stage in the breeding season and then decline. The study extends the early peak level throughout the season and evaluates the related expenditure of energy.

Mate preference and intra-sexual competition among females for access to preferred tan-striped males are responsible for the high rate of negative assortative mating in white-throated sparrow Zonotrichia albicollis. White-striped females outdo tan-striped females in their fight for tan-striped males, forcing tan-striped females to pair with white-striped males. Tan-striped monomorphic pairs face problems in retaining territories due to restricted territorial behavior and white-striped pairs have problems in fledgling chicks due to their limited chick feeding levels.

Purpose: Besides chiasmal hemidecussation, interhemispheric connections are likely important in human binocularity. The corpus callosum (CC) is the major fiber bundle in the mammalian brain which mostly connects homologous cortical areas in the two hemispheres. Visual interhemispheric connections were found abnormal in strabismic cats. No studies have investigated these pathways in humans with infantile strabismus. Methods: Diffusion tensor imaging was used in four subjects with infantile esotropia (IE) and nine control subjects with normal binocularity, in order to study interhemispheric fibers in the CC connecting the right and left primary visual cortical areas. Results: The number of callosal fibers linking both visual cortical areas between the hemispheres was found to be higher in subjects with IE. Also in IE, the amount of visual callosal fibers found after analysis from the primary visual cortical areas on one side appeared significantly different from the amount starting from the contralateral primary visual areas. The distribution area on one side is wider. Conclusion: We show callosal visual fibers to be abnormal in human IE. Subjects with IE showed abnormal numbers of transcallosal fibers connecting the visual cortical areas on both sides which likely results from an abnormal elimination process during development. Pruning of these fibers in IE favors the side of the visual cortex ipsilateral to the dominant eye. This study underlines the likely role of the CC in the development of human binocularity. [ABSTRACT FROM AUTHOR]