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Preventing spontaneous crystallization of supersaturated solutions by additives is of critical interest to successful process design and implementation, with numerous applications in chemical, pharmaceutical, medical, pigment, and food industries, but challenges remain in laboratory and industry settings and fundamental understanding is lacking. When copresented with antifreeze proteins (AFPs), otherwise spontaneously crystallizing osmolytes are maintained at high supersaturations for months in over-wintering organisms. Thus, we here explore the inhibition phenomenon by AFPs, using persistent crystallization of a common sugar alcohol, D-mannitol, as a case study. We report experimentally that DAFP1, an insect AFP, completely inhibits D-mannitol nucleation. Computer simulations reveal a new mechanism for crystallization inhibition where the population of the crystal-forming conformers are selectively bound and randomized in solution by hydrogen bonding to the protein surface. These results highlight the advantages of using natural polymers to address crystallization inhibition challenges and suggest new strategies in controlling the nucleation processes.

Access to research infrastructure for heritage science is the best way of narrowing the collections knowledge gap between resource-rich and resource-poor cultural institutions. Here we demonstrate a novel workflow that streamlines the use of a mobile laboratory for data collection (MOLAB) followed by a digital platform for data processing, analysis and interpretation (DIGILAB). The data collection and processing are taken care of by heritage science specialists, while the data analysis and interpretation can be performed collaboratively with conservators and curators. MOLAB with specialist personnel and mobile scientific instruments can sometimes be aided by in-house fixed laboratory (FIXLAB) equipment and personnel from resource-rich institutions to assist the resource-poor institutions if their collection can be hosted by the resource-rich institutions for analysis. The aim is to widen participation in the adoption of heritage science and material analysis in the understanding and conservation of collections, while ensuring high-quality, efficient and reliable data acquisition, processing, analysis and interpretation. The approach taken in this project combines access to various research infrastructure platforms to achieve extra benefit through adding further expert-assisted data analysis and interpretation capabilities, enabled by a new digital platform for data processing and visualisation. [ABSTRACT FROM AUTHOR]

When an animal detects a stressor, it initiates a stress response. The physiological aspects of this stress response are mediated through two endocrine systems. The catecholamine hormones epinephrine and norepinephrine are released from the adrenal medulla very rapidly and have numerous effects on behavior, metabolism, and the cardiovascular system. This is commonly termed the Fight-or-Flight response. On a longer time scale, the glucocorticoid hormones are released from the adrenal cortex. They interact with intracellular receptors and initiate gene transcription. This production of new proteins means that glucocorticoids have a delayed, but more sustained, effect than the catecholamines. The glucocorticoids orchestrate a wide array of responses to the stressor. They have direct effects on behavior, metabolism and energy trafficking, reproduction, growth, and the immune system. The sum total of these responses is designed to help the animal survive a short-term stressful stimulus. However, under conditions of long-term stress, the glucocorticoid-mediated effects become maladaptive and can lead to disease.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2008.11.013 Byline: Ken Yasukawa (a), Luke K. Butler (b), David A. Enstrom (c) Abstract: We conducted experiments on the intersexual and intrasexual consequences of epaulet colour in male red-winged blackbirds, Agelaius phoeniceus. In the female choice experiment, we gave captive females a choice between males with normal or dulled epaulets, and between males with normal or reddened epaulets. Females tended to associate more with normal males than with dulled males, but were equally likely to perform precopulatory displays to the two types of males. Females associated significantly more with redder-than-normal males and were more likely to perform precopulatory displays to reddened males. In the male-male competition experiment, we presented free-living territorial males with a male model to which we could attach wings with dulled, normal or reddened epaulets. Presence of the model with reddened epaulets resulted in significant increases in display rates by territory owners, but the increase in display rates was probably in response to males other than the territory owner flying through and trespassing rather than to the reddened epaulet model per se. Normal epaulets produced a significant decrease in song rates and approach distances of owners. Responses of territorial and other males did not differ significantly during normal and dulled epaulet presentations. These results support the hypothesis that epaulets of male red-winged blackbirds are salient inter- and intrasexual signals: unusually red epaulets were attractive to females and attracted more attention and aggression from male conspecifics than normal epaulets. Epaulet colour may thus be an example of intrasexual selection opposing intersexual selection. Author Affiliation: (a) Department of Biology, Beloit College, U.S.A. (b) Department of Biology, Tufts University, U.S.A. (c) Illinois Natural History Survey, University of Illinois, U.S.A. Article History: Received 15 May 2008; Revised 3 October 2008; Accepted 4 November 2008 Article Note: (miscellaneous) MS. number: A08-00320

We describe the timing and location of the prebasic molt in the Ash-throated Flycatcher (Myiarchus cinerascens), a hawking insectivore with resident populations in Mexico and migrant populations that breed in the western United States. The timing of fall molt with respect to migration is of particular interest for Ash-throated Flycatchers from the United States because they breed in arid lowland habitats that are probably unproductive in late summer, and because time constraints on molt might force northern populations to leave their breeding grounds before molting. Adults and juveniles depart their breeding grounds to arrive and molt in the region of the Mexican monsoon shortly after the monsoon rains begin. Diminishing food on the breeding grounds and increasing food in the monsoon region seem more important than time constraints for explaining molt-related movements by northern populations, because more southerly breeding birds east and west of the monsoon region also move to the monsoon region to molt. We found age class differences in the timing and duration of molt. In adults the primary molt starts approximately 14 July and requires 76 days to complete, whereas in juveniles, primary molt starts approximately 1 August (18 days after adults) but requires only 50 days to complete. We found no evidence that juveniles molt more primaries simultaneously than adults, so we conclude that the daily growth rate of individual feathers must be higher in juveniles than adults. Key words: Mexican monsoon, migration, molt, Myiarchus cinerascens. Describimos el momento y el lugar en que sucede la muda prebasica en Myiarchus cinerascens, un ave insectivora que tiene poblaciones residentes en Mexico y poblaciones migratorias que crian en el oeste de los Estados Unidos. El momento en que sucede la muda del otono con respecto a la migracion reviste un interes particular para las poblaciones de los Estados Unidos porque estas se reproducen en ambientes aridos de tierras bajas que probablemente son improductivos hacia el final del verano, y porque las limitaciones de tiempo sobre la muda podrian forzar a los individuos de las poblaciones del norte a abandonar sus sitios de cria antes de mudar. Los adultos y juveniles abandonan las areas reproductivas para llegar a la region monzonica mexicana, donde mudan poco despues del inicio de las lluvias monzonicas. La disminucion en la disponibilidad de alimento en las zonas de cria y su aumento en la region monzonica parecen ser mas importantes que las limitaciones de tiempo para explicar los movimentos de las poblaciones nortenas relacionados con la muda, pues las aves que se reproducen mas al sur en areas ubicadas al este y al oeste de la region monzonica tambien se desplazan hacia esta region para mudar. Encontramos diferencias entre clases de edad en cuanto al momento en que tiene lugar la muda yen cuanto a su duracion. En los adultos, la muda de las primarias se incia aproximadamente el 14 de julio y requiere 76 dias para completarse, mientras queen los juveniles se inicia aproximadamente el 18 de agosto (18 dias despues que en los adultos), pero requiere solo 50 dias para completarse. No encontramos evidencia de que los juveniles muden mas primarias de forma simultanea que los adultos, por lo que concluimos que la tasa de crecimiento diario de las plumas debe ser mayor en los juveniles.