Formation and dissolution of hen egg white lysozyme amyloid fibrils in protic ionic liquids

The formation of amyloid fibrils from non-disease-related proteins demonstrates that any protein can adopt this “rogue” form; we show that it is possible to use protic ionic liquids to fibrilize hen egg white lysozyme, and then subsequently to dissolve the fibrils with up to 72% restoration of enzymatic activity.

Structure–energy relations in hen egg white lysozyme observed during refolding from a quenched unfolded state

We use infrared spectroscopy to study the evolution of protein folding intermediate structures on arbitrarily slow time scales by rapidly quenching thermally unfolded hen egg white lysozyme in a glassy matrix, followed by reheating of the protein to refold; upon comparison with differential scanning calorimetric experiments, low-temperature structural changes that precede the formation of energetic native contacts are revealed.

High-speed pollen release in the white mulberry tree, Morus alba L

Anemophilous plants described as catapulting pollen explosively into the air have rarely attracted detailed examination. We investigated floral anthesis in a male mulberry tree with high-speed video and a force probe. The stamen was inflexed within the floral bud. Exposure to dry air initially resulted in a gradual movement of the stamen. This caused fine threads to tear at the stomium, ensuring dehiscence of the anther, and subsequently enabled the anther to slip off a restraining pistillode. The sudden release of stored elastic energy in the spring-like filament drove the stamen to straighten in less than 25 μs, and reflex the petals to velocities in excess of half the speed of sound. This is the fastest motion yet observed in biology, and approaches the theoretical physical limits for movements in plants.

Extending the surface force apparatus capabilities by using white light interferometry in reflection

The application of surface force apparatus (SFA) capabilities in measuring interactions between surfaces over nanometer separations was described. The technique is used when both the materials are transparent. It was observed that the poorly reflecting surface produce fringes that have low contrast and low finesse. The results show that the technique is successful when the visibility of the interference fringes is maximized.

White nation

Review of : White Nation : Fantasies of White Supremacy in a Multicultural Society, by Ghassan Hace, Pluto Press, 1998

The multiple relationships between the discipline of social work and the contributions of Michael White

Michael White, the Australian narrative practitioner, died in April this year. Given White trained in social work and has had a large impact on many social workers, it is timely to investigate the opaque relationships linking White and his work with his discipline-of-origin. The present examination proceeds in three steps. First, a schematic outline of White’s intellectual influences and achievements is set out; second, the alignments, as well as tensions, between White’s work and his discipline-of-origin are considered; and, third, it is argued that White was informed by, and went on to produce a body of work that further informed, the contesting spirit that is the wellspring of the discipline of social work. This conclusion is reached mindful of the fact that White remained antagonistic to the role played by the professions in general and that he did not identify with the title ‘social worker’ in particular.

Body image and self-esteem among Asian, Pacific Islander, and white college students in Hawaii and Australia

Body image and its relationship to self-esteem was examined among Asian, Pacific Islander, and White women and men from Hawaii and Australia (n = 172). Although Pacific Islander and White participants had higher body mass indices than Asians, Pacific Islanders were more satisfied than Asians with their health and more satisfied than Asians and Whites with their appearance. Thus, higher body weight and greater body satisfaction may co-occur among Pacific Islanders, whereas lower weight and lower body satisfaction may co-occur among Asians. The findings suggest different levels of risk for body image dissatisfaction, and its associated psychological consequences, across ethnic groups.

Effects of task lighting on visual function in age-related macular degeneration

The purpose was to investigate the effects of the spectral power distribution (SPD) and illuminance of task lighting on visual function in age-related macular degeneration (ARMD) compared to normal healthy eyes. Twenty-eight subjects with ARMD and 18 age-matched normal subjects were studied. The effects on visual function were determined for four common task light sources: standard pearl coat incandescent (SP), daylight blue incandescent (DL), warm white fluorescent (WW) and cool white fluorescent (CW). Apart from a small, statistically significant improvement in contrast sensitivity with DL compared to SP lighting (0.5 dB, p = 0.01), there were no significant effects of SPD on other visual functions and no differences in the effects for subjects with ARMD and those with normal vision. Thus, for task lighting typically used in low vision rehabilitation, the SPD would seem to be of minimal clinical importance to visual function. However, increasing the task illuminance had a greater effect on visual function, in particular for subjects with ARMD (p < 0.01). For an increase in illuminance from 300 to 3000 lux, the mean increase in contrast sensitivity and near visual acuity was 1.5 dB and 0.13 log MAR, respectively. Although this effect is not large, we suggest that it is clinically relevant and supports the provision of additional task illuminance as an important part of low vision rehabilitation for patients with ARMD.