A minichromosome of LGVI from crossing two quasi-terminal reciprocal translocations

Non-reciprocal translocations, in which one chromosome is a pure donor and another is a pure recipient, have found abundant uses in genetics, molecular biology, and cytology (Perkins 1997Advances in Genetics 36:239-398). Our original aim was to prepare a strain carrying a chromosome truncated in both arms, with the idea that such a small chromosome would be easily purified by pulsed field electrophoresis and would be a good preliminary substrate for genomic sequencing

Full Aging in Spin Glasses

The discovery of memory effects in the magnetization decays of spin glasses in 1983 began a large effort to determine the exact nature of the decay. While qualitative arguments have suggested that the decay functions should scale as $t_{w}$, the only time scale in the system, this type of scaling has not yet been observed. In this letter we report strong evidence for the scaling of the TRM magnetization decays as a function of $t_{w}$. By varying the rate and the profile that the sample is cooled through its transition temperature to the measuring temperature, we find that the cooling plays a major role in determining scaling. As the effective cooling time decreases, $\frac {t}{t_{w}}$scaling improves and for $t_{c}^{eff}<20s$ we find almost perfect $\frac{t}{t_{w}}$ scaling. We also find that subtraction of a stationary term from the magnetization decay has a small effect on the scaling but changes the form of the magnetization decay and improves overlap between curves produced with different $t_{w}$.Comment: 4 pages, 3 figure

‘Blindness to the obvious’?: Treatment experiences and feminist approaches to eating disorders

Eating disorders (EDs) are now often approached as biopsychosocial problems, but the social or cultural aspects of the equation are often marginalised in treatment - relegated to mere contributory or facilitating factors. In contrast, feminist and socio-cultural approaches are primarily concerned with the relationship between EDs and the social/ cultural construction of gender. Yet although such approaches emerged directly from the work of feminist therapists, the feminist scholarship has increasingly observed, critiqued and challenged the biomedical model from a scholarly distance. As such, this article draws upon data from 15 semi-structured interviews with women in the UK context who have experience of anorexia and/or bulimia in order to explore a series of interlocking themes concerning the relationship between gender identity and treatment. In engaging the women in debate about the feminist approaches (something which has been absent from previous feminist work), the article explores how gender featured in their own understandings of their problem, and the ways in which it was - or rather wasn’t - addressed in treatment. The article also explores the women’s evaluations of the feminist discourse, and their discussions of how it might be implemented within therapeutic and clinical contexts

Intense tumour-cell destruction by syngeneic mice: role of macrophages, complement activation and tumour-cell factors.

When injected i.p. and in large numbers (10(7)) into syngeneic mice, 125IUdR-labelled L1210 cells are rapidly destroyed in a small proportion of animals, while in the other animals the lysis is low. This bimodal distribution is clearly visible 24 h after cell injection. The intense lysis occurs in fewer animals when macrophage-derived lysosomal enzymes are inhibited by trypan blue and if the complement is depleted by high doses of cobra venom factor (CVF). The intense destruction occurs in more animals after adjuvant treatment, if the mice are latently contaminated, after a moderate production of C3b by low doses of CVF, or after the injection of a tumour-cell dialysate. The destruction seems to be the result of positive feedback reaction which involves at least macrophages and complement activation

A miniprep procedure for isolating genomic DNA from Magnoporthe grisea

We have developed a simple miniprep procedure for the isolation of genomic DNA from the ascomycete Magnaporthe grisea. This pathogen of many grasses, including rice, has a moderate growth rate and produces intermediate to low numbers of conidia when grown in culture. Thus, in our previous DNA preparation procedure we inoculated swirling liquid cultures with mycelium that had been fragmented in a blender rather than with conidia. The mycelium obtained from these cultures was ground in liquid nitrogen for DNA extraction. Though the quantity and quality of DNA obtained by this method is satisfactory, the technique is too laborious for analysis of many strains. We developed the procedure described below to eliminate the need to fragment mycelium in a blender to inoculate cultures and to eliminate the need to grind mycelium in liquid nitrogen for DNA extraction. The new procedure, which relies on the enzymatic removal of cell walls and the lysis of protoplasts, should be readily adaptable to other filamentous fungi with growth characteristics similar to those of M. grisea

Magnetocaloric Study of Spin Relaxation in `Frozen' Dipolar Spin Ice Dy2Ti2O7

The magnetocaloric effect of polycrystalline samples of pure and Y-doped dipolar spin ice Dy2Ti2O7 was investigated at temperatures from nominally 0.3 K to 6 K and in magnetic fields of up to 2 T. As well as being of intrinsic interest, it is proposed that the magnetocaloric effect may be used as an appropriate tool for the qualitative study of slow relaxation processes in the spin ice regime. In the high temperature regime the temperature change on adiabatic demagnetization was found to be consistent with previously published entropy versus temperature curves. At low temperatures (T < 0.4 K) cooling by adiabatic demagnetization was followed by an irreversible rise in temperature that persisted after the removal of the applied field. The relaxation time derived from this temperature rise was found to increase rapidly down to 0.3 K. The data near to 0.3 K indicated a transition into a metastable state with much slower relaxation, supporting recent neutron scattering results. In addition, magnetic dilution of 50 % concentration was found to significantly prolong the dynamical response in the milikelvin temperature range, in contrast with results reported for higher temperatures at which the spin correlations are suppressed. These observations are discussed in terms of defects and loop correlations in the spin ice state.Comment: 9 figures, submitted to Phys. Rev.

Anharmonic Decay of Vibrational States in Amorphous Silicon

Anharmonic decay rates are calculated for a realistic atomic model of amorphous silicon. The results show that the vibrational states decay on picosecond timescales and follow the two-mode density of states, similar to crystalline silicon, but somewhat faster. Surprisingly little change occurs for localized states. These results disagree with a recent experiment.Comment: 10 pages, 4 Postscript figure

Limitations for change detection in multiple Gabor targets

We investigate the limitations on the ability to detect when a target has changed, using Gabor targets as simple quantifiable stimuli. Using a partial report technique to equalise response variables, we show that the log of the Weber fraction for detecting a spatial frequency change is proportional to the log of the number of targets, with a set-size effect that is greater than that reported for visual search. This is not a simple perceptual limitation, because pre-cueing a single target out of four restores performance to the level found when only one target is present. It is argued that the primary limitation on performance is the division of attention across multiple targets, rather than decay within visual memory. However in a simplified change detection experiment without cueing, where only one target of the set changed, not only was the set size effect still larger, but it was greater at 2000 msec ISI than at 250 msec ISI, indicating a possible memory component. The steepness of the set size effects obtained suggests that even moderate complexity of a stimulus in terms of number of component objects can overload attentional processes, suggesting a possible low-level mechanism for change blindness