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One of the most fascinating and puzzling features of collective action is the fact that people undertake potentially high-risk protests with little likelihood of reward. Take the widespread protests of early October 1989 in East Germany which had high chances of being repressed and low chances of achieving success. Why are people time and again prepared to participate in protests?

POLCON ERC AdG Grant Agreement no 338875

Ticks are among the most significant human-biting ectoparasites and they play a major role in transmission of many pathogenic agents to humans. In the present study, three species of Hyalomma ticks, Hyalomma aegyptium, H. marginatum and H. excavatum, were examined for the presence of zoonotic bacteria, both male and female ticks alike. Examination of microbial diversity with tag-encoded pyrosequencing indicates that H. marginatum and H. excavatum were more diversity rich than H. aegyptium. Although numerous pathogenic and non-pathogenic bacterial genera were detected, including Acidovorax, Bacillus, Bacteroides, Bdellovibrio, Clostridium, Curvibacter, Escherichia, Flavobacterium, Limnohabitans, Paenibacillus, Ralstonia, Sarcina, Sediminibacterium, Segetibacter Stenotrophomonas and Variovorax, the predominant zoonotic bacteria represented in these ticks were genera Borrelia, Francisella, and Rickettsia. To the authors' knowledge, this work represents the first detection of Yersinia enterocolitica in the tick H. excavatum, raising questions regarding the vector competency of this tick, as well as associations of different disease representations perhaps through previously unforeseen routes of pathogen introduction. Likewise, similar questions are related to the presence of Legionella pneumophila in one H. excavatum sample.

Thermal expansion, electrical resistivity, magnetization, and specific heat measurements were performed on URu2-xFexSi2 single crystals for various values of Fe concentration x in both the hidden-order (HO) and large-moment antiferromagnetic (LMAFM) regions of the phase diagram. Our results show that the paramagnetic (PM) to HO and LMAFM phase transitions are manifested differently in the thermal expansion coefficient. The uniaxial pressure derivatives of the HO/LMAFM transition temperature T0 change dramatically when crossing from the HO to the LMAFM phase. The energy gap also changes consistently when crossing the phase boundary. In addition, for Fe concentrations at xc ≈ 0.1, we observe two features in the thermal expansion upon cooling, one that appears to be associated with the transition from the PM to the HO phase and another one at lower temperature that may be due to the transition from the HO to the LMAFM phase.

This article reexamines spontaneity as an important, albeit neglected, mechanism in collective action dynamics, and elaborates on its operation and effects in protest events and social movements. We do not presume that spontaneity is routinely at play in all collective actions. Rather, based on our grounded analysis of historical and ethnographic data, we contend that spontaneity is triggered by certain conditions: nonhierarchical organization; uncertain/ambiguous moments and events; behavioral/emotional priming; and certain ecological/spatial factors. We conclude by elaborating why the activation of spontaneous actions matters in shaping the course and character of protest events and movements, and we suggest that spontaneity be resuscitated in the study of collective action and everyday life more generally.

Comportamiento alimentario de picaflores en la Serra do Mar, sudeste de Brasil. El comportamiento alimentario de picaflores fue estudiado en noviembre y diciembre de 1983 en Boracéia, una selva muy húmeda en la Serra do Mar a 800-900 m. Seis especies de picaflores estuvieron presentes en el área y fueron registrados tomando néctar de 25 especies de plantas nativas, de las cuales 15 o 16 fueron consideradas estar adaptadas a picaflores. Tanto el número de especies de picaflores como de individuos fue menor comparado con los números ocurridos en otras áreas de selvas húmedas neo tropicales. El porcentaje de visitas a plantas nativas para alimentarse fue bajo y la cantidad de consumo de insectos fue relativamente alta. Se argumenta que la baja diversidad y abundancia de picaflores está en relación a una escasa provision de néctar. Sobre la base de los limitados datos disponibles, parece que dos familias de plantas que son importantes para picaflores en los Andes y otras áreas montañosas neotropicales, como son las Rubiaceae y Ericaceae, proveen poco néctar para picaflores de selvas en la Serra do Mar, y que esto puede parcialmente explicar la ausencia de diversidad en la longitud del pico de los picaflores. La forma en la cual la comunidad de picaflores que viven en un área explotan las flores es de interés tanto desde el punto de vista ornitológico como botanico. Es también de gran interés evolutivo, por·que puede explicar la coevolución de picaflores y plantas. The feeding behaviour of hummingbirds was studied in November and December 1983 at Boracéia, an area of very humid forest in the Serra do Mar, SE Brazil at 800-900 m. Six species of hummingbirds were present in the area, and were recorded taking nectar from 25 native plant species, of which 15 or 16 were considered to be hummingbird-adapted. Both the number of hummingbird species and the number of individuals were small compared with the numbers occurring in humid forest e1sewhere in the neotropics. The rate of feeding·visits to native plants was low, anther amount of insect-foraging was relatively high. It is argued that low hummingbird diversity and abundance were related to a sparse nectar supply. On the. basis of the limited data available, it seems that two plant families that are important for hummingbirds in the Andes and in other montane areas in the neotropics, the Rubiaceae and Ericaceae, provide littie nectar for forest hummingbirds in the Sena do Mar, and that this may partly account for the lack of diversity in hummingbird bill lengths. The way in wich the·community of hummingbirds living in an area exploits the flowers of that area is of both omithological and botanical interest. It is also of wider evolutionary interest, as it may throw light on the coevolution of hummingbhds and plants.