Timing and time perception : a selective review and commentary on recent reviews

Keywords : Time perception, Attention, Animals, Humans, Commentar

Shear-induced fractures and three-dimensional motions in an organogel

The flow behavior of a viscoelastic organogel is investigated using ultrasonic velocimetry combined with rheometry. Our gel presents a decreasing flow curve, i.e., the measured stress decreases as a function of the applied shear rate. Strikingly, we note that the local flow curve calculated from the velocity profiles also exhibits a decreasing part. We attribute this regime to the presence of a fracturing process and three-dimensional motions in the bulk of the sample.Comment: 13 pages, 19 figure

Assessment of the relationship between genotypic status of a DT-diaphorase point mutation and enzymatic activity

DT-diaphorase, a cytosolic reductase, has been implicated as an activator of chemotherapeutic prodrugs and a detoxifier of certain potentially carcinogenic xenobiotics. A common C to T nucleotide 609 substitution in DT-diaphorase cDNA has been associated with protein instability and reduced catalytic activity. The degree to which the allelic status of the substitution correlates with enzymatic activity was assessed in 45 normal human skin fibroblast strains using a PCR-RFLP assay. Included in this study was the 3437T strain, which is unique in that it is heterozygous for the polymorphism yet contains undetectable enzymatic activity. An allele-specific RT-PCR-RFLP technique attributed this phenomenon to exclusive DT-diaphorase mRNA expression from the variant allele. Overlap in activities was observed between individual strains homozygous for the wild-type allele and heterozygotes, but the former group displayed enzymatic activity that was on average 2-fold higher. Western blot analysis of the two strains in this panel that are homozygous for the variant allele revealed that they express relatively low amounts of DT-diaphorase protein, consistent with the role of the substitution in protein instability. This work confirms that genotypic status is a reliable initial estimate of DT-diaphorase activity. © 2000 Cancer Research Campaig

'Lad culture' in higher education: agency in the sexualisation debates

This paper reports on research funded by the National Union of Students, which explored women students’ experiences of ‘lad culture’ through focus groups and interviews. We found that although laddism is only one of various potential masculinities, for our participants it dominated social and sexual spheres of university life in problematic ways. However, their objections to laddish behaviours did not support contemporary models of ‘sexual panic’, even while oppugning the more simplistic celebrations of young women’s empowerment which have been observed in debates about sexualisation. We argue that in their ability to reject ‘lad culture’, our respondents expressed a form of agency which is often invisibilised in sexualisation discussions and which could be harnessed to tackle some of the issues we uncovered

The zebrafish reveals dependence of the mast cell lineage on Notch signaling in vivo

We used the opportunities afforded by the zebrafish to determine upstream pathways regulating mast cell development in vivo and identify their cellular origin. Colocalization studies demonstrated zebrafish notch receptor expression in cells expressing carboxypeptidase A5 (cpa5), a zebrafish mast cell-specific marker. Inhibition of the Notch pathway resulted in decreased cpa5 expression in mindbomb mutants and wild-type embryos treated with the γ-secretase inhibitor, Compound E.Aseries of morpholino knockdown studies specifically identified notch1b and gata2 as the critical factors regulating mast cell fate. Moreover, hsp70::GAL4;UAS::nicd1a transgenic embryos overexpressing an activated form of notch1, nicd1a, displayed increased cpa5, gata2, and pu.1 expression. This increase in cpa5 expression could be reversed and reduced below baseline levels in a dose-dependent manner usingCompound E. Finally, evidence that cpa5 expression colocalizes with lmo2 in the absence of hematopoietic stem cells revealed that definitive mast cells initially delineate from erythromyeloid progenitors. These studies identify a master role for Notch signaling in vertebrate mast cell development and establish developmental origins of this lineage. Moreover, these findings postulate targeting the Notch pathway as a therapeutic strategy in mast cell diseases. © 2012 by The American Society of Hematology

Improving Digital Library Experiences and Support with Online Research Guides

With a goal of improving the development and delivery of effective online information literacy resources, the purpose of this study was to look at how program level and the timing of the introduction of a Literature Review library guide influenced online business student perceived value of the resource.  A population of undergraduate business students (N=355) and online MBA students (N=319) were introduced to a Literature Review library guide during specific points in their programs.  Students were asked to complete an online survey that included 17 closed-ended items designed to measure perceived usefulness, satisfaction and likeliness to use the guide again.  The survey also included two open-ended questions asking students to discuss those elements of the guide they found most valuable and whether any features had not been included in the guide, but which they would have liked to see. The data collection strategy required faculty post information about the Literature Review library guide and the survey in their courses at two specified times in the course. A low response rate (3.5%) resulted from inconsistencies in faculty including information about the guide and study in their courses.  Although the small sample size (n=24) limited the planned analysis and resulted in no statistical significance between groups, descriptive findings were reported, and trends were used to revise the resource and inform future development of library research guides. Overall, students reported being satisfied with the resource and found it usable.  Graduate students were more likely to report elements of the guide that supported effective search and evaluation strategies were valuable; whereas, undergraduate students tended to value the links to writing resources.  Student feedback also suggested that the earlier the guide was introduced in the program, the more likely students would use the resource.  Adopting a model that embeds resource guides early, and aligning guide content with the curriculum should lead to increased use of the resource