The shadow response of the cockroach periplaneta americana

We show that the “escape response” (running) of the cockroach Periplaneta americana is interrupted when the insect runs through a shadow. Shadows were cast by holding an opaque plastic sheet so that the cockroach ran beneath it. In control experiments, a similarly positioned clear plastic sheet was ineffective. Removal of the shadow stimulus allowed running to continue. The likelihood that cockroaches would resume running after removal of the shadow stimulus decreased with the time they were allowed to remain in shadow.     

The shadow of life: Psychosocial explanations for placenta rituals

Culturally determined patterns of behavior associated with placenta disposal are characteristic of many modern and ancient societies. This paper defines this type of placenta disposal as a ritual event that delimits a portion of reality; explanations are provided leading to the conclusion that placenta rituals operate as anxiety releasing mechanisms that provide a means of control over the future health and welfare of mother, child, and community. The question of why the placenta figures so prominently in folk beliefs and practices has previously been attributed to its morphological and physiological properties; this paper argues that attributes associated with it from a psychosocial model are equally important. The data for this study were drawn from a compilation of ethnographic reports of post-partum practices in African, Asian, European, and Latin American societies. Additional information on placenta disposal was derived from interviews with 1,859 Peruvian informants. Analysis of the data obtained from the Peruvian studies show a significant difference between rural and semi-urban patterns of placenta disposal.I am using the term ritual to refer to the culturally determined behavioral sequences that relate to the placenta. The basis of the explanatory system that I have proposed in this article to account for its cross-cultural importance is that these behavioral sequences are examples of secular rituals as defined by Moore and Meyerhoff 1977: 3–24.     

The shadow of death on the MET tyrosine kinase receptor

The MET tyrosine kinase receptor is a high-affinity receptor for hepatocyte growth factor/scatter factor (HGF/SF). HGF/SF-MET system is necessary for embryonic development, and aberrant MET signalling favours tumorigenesis and metastasis. MET is a prototype of tyrosine kinase receptor, which is able to counteract apoptosis through the initiation of a survival signal involving notably the PI3K-Akt pathway. Paradoxically, the MET receptor is also able to promote apoptosis when activated by HGF/SF or independently of ligand stimulation. The molecular mechanisms underlying this uncommon response have been recently investigated and revealed dual antiapoptotic or proapoptotic property of MET according to the cell type or stress conditions. Although the involvement of MET in the regulation of integrated biological responses mostly took into account its efficient antiapoptotic function, its proapoptotic responses could also be important for regulation of the survival/apoptosis balance and play a role during the development or tumour progression.     

A risk shadow in Spain

This paper describes a period of intense risk construction in Spain. By autumn 2000 there was a coincidence of different alarming events affecting Spanish society and widely covered by media. A feeling of risk extended all around and the Spanish political agenda was, for a time, dominated by risk issues. This paper tries to establish how useful the concept of 'risk shadow' can be in order to analyse the construction of risk in a global context. The narratives of risk seem to give this phenomenon its cultural consistency, because more than a scientific fact, risk construction is a cultural matter.     

The HP1 chromo shadow domain binds a consensus peptide pentamer

Heterochromatin-associated protein 1 (HP1) is thought to affect chromatin structure through interactions with other proteins in heterochromatin. Chromo domains located near the amino (amino chromo) and carboxy (chromo shadow) termini of HP1 may mediate such interactions, as suggested by domain swapping, in vitro binding and 3D structural studies . Several HP1-associated proteins have been reported, providing candidates that might specifically complex with the chromo domains of HP1. However, such association studies provide little mechanistic insight and explore only a limited set of potential interactions in a largely non-competitive setting. To determine how chromo domains can selectively interact with other proteins, we probed random peptide phage display libraries using chromo domains from HP1. Our results demonstrate that a consensus pentapeptide is suffident for specific interaction with the HP1 chromo shadow domain. The pentapeptide is found in the amino acid sequence of reported HP1-associated proteins, including the shadow domain itself. Peptides that bind the shadow domain also disrupt shadow domain dimers. Our results suggest that HP1 dimerization, which is thought to mediate heterochromatin compaction and cohesion, occurs via pentapeptide binding. In general, chromo domains may function by avidly binding short peptides at the surface of chromatin-associated proteins.     

The long shadow of the Kargil War: The effect of early-life stress on education

The paper examines the long-term impact of the India-Pakistan war of 1999 on the educational attainment of children born to families of soldiers who survived the war. Based on the assumption that military families faced higher levels of psychological stress than civilian families during the war period, the paper uses a difference-in-difference methodology with household fixed effects to show that the education of military children exposed to the war during their formative years suffered significantly. An examination of the consumption expenditure pattern of military and civilian households suggests that the effect was unlikely to be via resource-related channels. The improbability of other direct pathways through which the war could affect these families suggests that the negative effect might have resulted from the psychological stress that the war generated for the affected families.     

The shadow of forgotten ancestors differently constrains the fate of Alligatoroidea and Crocodyloidea

Aim We tested the hypothesis that the evolutionary fates of two sister groups (Alligatoroidea and Crocodyloidea) are differently constrained by phylogenetic and ecological (functional) factors in the face of climatic change. Location Global. Methods We quantified disparity in skull rostrum shape by means of geometric morphometrics. Mechanical performance of the rostrum was analyzed by applying beam theory calculations to morphological data and experimentally measured bite force. The phylogeny was expressed in the form of principal coordinates, the first ones of which were used as a set of explanatory variables. Extents of species occurrence were computed using species distribution maps. Finally, species maximum skull size were measured and considered as a proxy of maximum body size. We performed variation partitioning analyses in order to compare differential contributions of phylogenetic and ecological factors in Alligatoroidea and Crocodyloidea. Results Alligatoroidea show higher ‘pure’ historical components than Crocodyloidea in explaining both rostrum shape and extent of occurrence (after controlling for body size). On the contrary, geometric variation of skull rostra of Crocodyloidea unequivocally shows a higher ‘pure’ functional component (linked to performance on prey capture) and a higher phylogenetically structured environmental variation than those found in Alligatoroidea. Results obtained for body size variation are consistent with these patterns. In Alligatoroidea, body size variation contains a higher phylogenetic signal than in Crocodyloidea. Main Conclusions Our results suggest that Crocodyloidea and Alligatoroidea may react differently when faced with significant environmental changes. We predict that global climatic changes will have a more important effect on Crocodyloidea than in Alligatoroidea by (1) promoting trait shift, adaptation to the new diet and speciation and (2) modifying the geographical range distribution of species (which may track favourable ecological conditions).     

The bicarbonate effect,oxygen evolution,and the shadow of Otto Warburg

A short list of the twentieth century's dominant figures in photosynthesis would unquestionably include Otto Warburg. One of his many discoveries, the `bicarbonate effect' remains a lasting puzzle to his heirs in the field. Recent developments in this area of research have renewed interest and call for a re-examination of the ideas surrounding this controversial topic. Focus here will be on hypotheses developed by a small number of researchers who proposed that bicarbonate may be involved in oxygen evolution. The effect of bicarbonate on the acceptor side of Photosystem II (PS II) is discussed by Jack van Rensen (in this issue). This revised version was published online in June 2006 with corrections to the Cover Date.     

Neuroeconomics: the shadow of the future

Humans and other animals tend to disregard future benefits and costs when choosing between immediate and delayed gratification. This tendency can lead to the choice of options that are not in one's own long-term interest. A new study looks at the neurophysiological basis of this self-defeating behavior.