At metaphase, DNA in a human chromosome is estimated to be compacted at least 10,000 fold in length.1,2 However, the higher order mechanisms by which the chromosomes are organized in interphase and subsequently further condensed in mitosis have largely remained elusive. One generally overlooked participant in chromosome condensation is DNA replication. Many early studies of eukaryotic chromosome organization and cell fusions have suggested that DNA replication plays a role in chromosome compaction. Recent phenotypic analysis of Drosophila DNA replication mutants has (...) revitalized this old idea. In this review, the role of DNA replication in chromosome condensation will be examined. BioEssays 24:411–418, 2002. © 2002 Wiley Periodicals, Inc. (shrink)

Este texto propõe discutir a controvérsia sobre o uso dos transgênicos na agricultura e pergunta também pela possibilidade de uma alternativa melhor a eles. Quando falamos em controvérsia, referimo-nos a uma discussão sobre ideias que refletem posturas opostas. Serão, portanto, apresentadas duas perspectivas distintas a respeito do tema: a perspectiva dos proponentes da transgenia e a dos críticos. A partir da perspectiva crítica, a agroecologia será elencada como possível alternativa para produção de alimentos considerando sua dimensão ética.

As competition over peer status becomes intense during adolescence, some adolescents develop insecure feelings regarding their social standing among their peers. These adolescents sometimes use aggression to defend or promote their status. The aim of this study was to examine the relationships among social status insecurity, callous-unemotional traits, and popularity-motivated aggression and prosocial behaviors among adolescents, while controlling for gender. Another purpose was to examine the potential moderating role of CU traits in these relationships. Participants were 1,047 in the 7th (...) or 8th grades from a large Midwestern city. They completed questionnaires on social status insecurity, CU traits, and popularity-motivated relational aggression, physical aggression, cyberaggression, and prosocial behaviors. A structural regression model was conducted, with gender as a covariate. The model had adequate fit. Social status insecurity was associated positively with callousness, unemotional, and popularity-motivated aggression and related negatively to popularity-motivated prosocial behaviors. High social status insecurity was related to greater popularity-motivated aggression when adolescents had high callousness traits. The findings have implications for understanding the individual characteristics associated with social status insecurity. (shrink)

To provide the three-way comparisons needed to test existing theories, we compared (1) most-stressful memories to other memories and (2) involuntary to voluntary memories (3) in 75 community dwelling adults with and 42 without a current diagnosis of posttraumatic stress disorder (PTSD). Each rated their three most-stressful, three most-positive, seven most-important and 15 word-cued autobiographical memories, and completed tests of personality and mood. Involuntary memories were then recorded and rated as they occurred for 2 weeks. Standard mechanisms of cognition and (...) affect applied to extreme events accounted for the properties of stressful memories. Involuntary memories had greater emotional intensity than voluntary memories, but were not more frequently related to traumatic events. The emotional intensity, rehearsal, and centrality to the life story of both voluntary and involuntary memories, rather than incoherence of voluntary traumatic memories and enhanced availability of involuntary traumatic memories, were the properties of autobiographical memories associated with PTSD. (shrink)

Previous research on youths’ online risky experiences has mostly utilized quantitative designs. However, some of this research does not account for youths’ views and perceptions. This qualitative study fills this gap by describing online problematic situations from the perspectives of European youths, focuses on classifying online problematic situations based on youths’ perspectives and interrelates these with their developmental contexts. As a theoretical framework, the co-construction model was adopted, which proposes that youths’ online and offline worlds are interconnected. Interviews and focus (...) groups were conducted with youths between the ages of 9 and 16 from Belgium, the Czech Republic, Greece, Malta, Italy, Portugal, Romania, Spain, and the United Kingdom. Youths’ responses reflected the complexity of the various problematic situations online they encountered or indirectly experienced, and how such experiences were interconnected with the developmental contexts of peer relationships, parent-child relationships, romantic relationships, school, sexuality, identity, health, and morality. We recommend the development of complex educational programs focused on youths about problematic situations online, which discuss the possible situations they may encounter and how to deal with them. (shrink)

O presente relato nasce de um projeto pedagógico desenvolvido na Aldeia Tupinikim de Comboios, município de Aracruz- ES, durante a disciplina Projetos de Pesquisa e Prática Pedagógica – PPPP III, no curso de Licenciatura Intercultural Indígena Tupinikim e Guarani, do Programa de Licenciaturas Indígenas – PROLIND, oferecido pela Universidade Federal do Espírito Santo – UFES. O projeto teve como objetivos: Pesquisar com os mais velhos os tipos de trançados, colaborando na reafirmação cultural do nosso povo Tupiniquim; Reconhecer os tipos de (...) trançados Tupiniquim; Confeccionar alguns tipos de trançados; Produzir textos coletivos a partir dos trançados e analisar o processo de letramento a partir de atividades contextualizadas. O projeto se apoiou metodologicamente na pesquisa-ação com intuito de identificar as técnicas e manuseios dos trançados Tupinikim, construindo momentos de partilhas com os anciãos e intercâmbios entre outras aldeias Tupinikim. (shrink)

Academic dishonesty has serious consequences for human lives, social values, and economy. The main aim of the study was to explore a model of relations between personal and cultural variables and academic dishonesty. The participants in the study were N = 2,586 individuals from nine countries (Pakistan, Israel, Italy, India, the USA, Peru, Romania, Ghana, and Poland). The authors administered the Academic Dishonesty Scale to measure academic dishonesty, the Kessler Psychological Distress Scale to measure distress, the Almost Perfect Scale – (...) Revised to measure perfectionism, the Brief Self-Control Scale to measure self-control, and the Singelis Scale to measure independent self-construal. The results showed that the theoretical model was well fitted to the dataset in six countries: Pakistan, the United States, Romania, Ghana, Israel, and Poland. However, it was not well fitted in Italy, India, and Peru. Our results also showed that perfectionism significantly predicted academic dishonesty, but not in all countries. Self-control significantly predicted cheating, falsification, and plagiarism in the USA. Moreover, we found that distress was related to cheating o0nly in Ghana. Finally, independent self-construal predicted academic dishonesty. Our findings provide a cross-cultural contribution to the debate on academic dishonesty by highlighting its significant predictors and may inform interventions aimed at eliminating it. Our results can be used in preventing and curbing academic dishonesty. Knowledge on cross-cultural differences can be useful in international education for example, as an indicator accepting or relaxing attitude toward academic dishonesty in students from different countries. (shrink)

After satisfying their quantitative and qualitative needs as regards nutrition, consumers in developed countries are becoming more involved in the ethical aspects of food production, especially when it relates to animal products. Social demands for respecting animal welfare in housing systems are increasing rapidly, as is social awareness of human responsibility towards farm animals. Many studies have been conducted on animal welfare measurement in different production systems, but the available information for small ruminants remains insufficient. In this study, a 75 (...) criteria-evaluation tool has been set up on the basis of the five freedoms concept. Animal welfare considerations have been analyzed in 25 documents, including labeling schemes, regulations, and recommendations from different European countries. The results show many differences between regular and organic small ruminant farming standards. Emergency measures are generally lacking. A weak representation of psychological aspects of animal welfare, especially by the current European legislation, is highlighted. (shrink)

The emergence of environmental governance practices raises a fundamental question as to whether they are substantive or symbolic. Toward that end, we analyze the relationship between a firm’s environmental governance and its environmental management as reflected in its ultimate outcome, environmental performance. We posit that substantive practices would bring changes in organizations, most notably in terms of improved environmental performance, whereas symbolic practices would portray organizations as environmentally committed without making meaningful changes to their operations. Focusing on a sample of (...) environmentally sensitive firms, results are consistent with environmental governance mechanisms being predominantly part of a symbolic approach to manage stakeholder perceptions on environmental management, having little substantial impact on organizations. Statistical analyses show mostly that there is no relation between environmental governance mechanisms and environmental performance, measured in terms of regulatory compliance, pollution prevention, and environmental capital expenditures. However, there is some indication that environmental incentives are associated with pollution prevention. Interviews with corporate directors shed further light on these results by underlining that environmental governance mechanisms are employed at the board level to protect the organization from reputational and/or regulatory harm, but are not necessarily intended to proactively improve environmental performance. (shrink)

The purpose of the present paper is to reply to a misleading paper by M. Sachs entitled “Einstein's later view of the Twin Paradox” (TP) (Found. Phys. 15, 977 (1985)). There, by selecting some passages from Einstein's papers, he tried to convince the reader that Einstein changed his mind regarding the asymmetric aging of the twins on different motions. Also Sachs insinuates that he presented several years ago “convincing mathematical arguments” proving that the theory of relativity does not predict asymmetrical (...) aging in the TP. Here we give a definitive treatment to the clocks problem showing that Sachs' “convincing mathematical arguments” are non sequitur. Also, by properly quoting Einstein, we show that his later view of the TP coincides with the one derived from the rigorous theory of time developed in this paper. (shrink)

The scientific study of consciousness emerged as an organized field of research only a few decades ago. As empirical results have begun to enhance our understanding of consciousness, it is important to find out whether other factors, such as funding for consciousness research and status of consciousness scientists, provide a suitable environment for the field to grow and develop sustainably. We conducted an online survey on people’s views regarding various aspects of the scientific study of consciousness as a field of (...) research. 249 participants completed the survey, among which 80% were in academia, and around 40% were experts in consciousness research. Topics covered include the progress made by the field, funding for consciousness research, job opportunities for consciousness researchers, and the scientific rigor of the work done by researchers in the field. The majority of respondents (78%) indicated that scientific research on consciousness has been making progress. However, most participants perceived obtaining funding and getting a job in the field of consciousness research as more difficult than in other subfields of neuroscience. Overall, work done in consciousness research was perceived to be less rigorous than other neuroscience subfields, but this perceived lack of rigor was not related to the perceived difficulty in finding jobs and obtaining funding. Lastly, we found that, overall, the global workspace theory was perceived to be the most promising (around 28%), while most non-expert researchers (around 22% of non-experts) found the integrated information theory (IIT) most promising. We believe the survey results provide an interesting picture of current opinions from scientists and researchers about the progresses made and the challenges faced by consciousness research as an independent field. They will inspire collective reflection on the future directions regarding funding and job opportunities for the field. (shrink)

Lee emphasizes the need to better understand the moral relationship between researchers and participants connoted by precision medicine, with the framework of “the gift” offering bioethics a...

In this article, Peter and Rowland explore the role of implicit statistical learning in syntactic development. It is often accepted that the processes observed in classic implicit learning or statistical learning experiments play an important role in the acquisition of natural language syntax. As Peter and Rowland point out, however, the results from neither research strand can be used to fully explain how children's syntax becomes adult‐like. They propose to address this shortcoming by using the structural priming paradigm.

Activity in the prefrontal cortex may distinguish the meta-awareness experienced during lucid dreams from its absence in normal dreams. To examine a possible relationship between dream lucidity and prefrontal task performance, we carried out a prospective study in 28 high school students. Participants performed the Wisconsin Card Sort and Iowa Gambling tasks, then for 1 week kept dream journals and reported sleep quality and lucidity-related dream characteristics. Participants who exhibited a greater degree of lucidity performed significantly better on the task (...) that engages the ventromedial prefrontal cortex, but degree of lucidity achieved did not distinguish performance on the task that engages the dorsolateral prefrontal cortex, nor did it distinguish self-reported sleep quality or baseline characteristics. The association between performance on the Iowa Gambling Task and lucidity suggests a connection between lucid dreaming and ventromedial prefrontal function. (shrink)

Mucoidy and cytotoxicity arise from two independent modifications of the phenotype of the bacterium Pseudomonas aeruginosa that contribute to the mortality and morbidity of cystic fibrosis. We show that, even though the transcriptional regulatory networks controlling both processes are quite different from a molecular or mechanistic point of view, they may be identical from a dynamic point of view: epigenesis may in both cases be the cause of the acquisition of these new phenotypes. This was highlighted by the identity of (...) formal graphs modelling these networks. A mathematical framework based on formal methods from computer science was defined and implemented with a software environment. It allows an easy and rigorous validation and certification of these models and of the experimental methods that can be proposed to falsify or validate the underlying hypothesis. (shrink)

The conviction, due to previous failures, that bacteriology and darwinism were incompatible, has postponed the application of molecular phylogenesis to bacteria. But once introduced, this new field has led to a profound revolution of this science. A stable classification of the bacteria is at last possible; a new domain, the Archae, as distant from the Bacteria as from the Eukarya, has been discovered; noncultivable new species can be identified from the environment. It may even be possible to unravel the pathway (...) of early evolution after the common ancestor. However, controversies on this subject are already disregarded by the new paradigm. (shrink)

Intellectual property in biotechnology invention provides important incentives for research and development leading to advances in genetic tests and treatments. However, there have been numerous concerns raised regarding the negative effect patents on gene sequences and their practical applications may have on clinical research and the availability of new medical tests and procedures. One concern is that licensing policies attempting to capture for the benefit of the licensor valuable rights to downstream research results and products may increase the financial risks (...) and cliniinish potential payoffs of — and therefore motivation for — performing downstream research and development. In addition, very broad patent claims allowed by the U.S. Patent and Trademark Office, the sheer growth in patents claiming genetic sequences, and threats of overlapping patents create a veritable minefield for researchers in both academia and industry. The concern is that research may be stifled because of the high cost and hassle of negotiating access. (shrink)

The future of work is forcing the world to adjust to a new paradigm of working. New skills will be required to create and adopt new technology and working methods. Additionally, cognitive skills, particularly creative problem-solving, will be highly sought after. The future of work paradigm has threatened many occupations but bolstered others such as engineering. Engineers must keep up to date with the technological and cognitive demands brought on by the future of work. Using an exploratory mixed-methods approach, our (...) study sought to make sense of how engineers understand and use creative problem solving. We found significant associations between engineers’ implicit knowledge of creativity, exemplified creative problem solving, and the perceived value of creativity. We considered that the work environment is a potential facilitator of creative problem-solving. We used an innovative exceptional cases analysis and found that the highest functioning engineers in terms of knowledge, skills, and perceived value of creativity, also reported working in places that facilitate psychosocially safe environments to support creativity. We propose a new theoretical framework for a creative environment by integrating the Four Ps and psychosocial safety climate theory that management could apply to facilitate creative problem solving. Through the acquisition of knowledge to engage in creative problem solving as individuals or a team, a perception of value must be present to enforce the benefit of creativity to the engineering role. The future of work paradigm requires that organisations provide an environment, a psychosocially safe climate, for engineers to grow and hone their sought-after skills that artificial technologies cannot currently replace. (shrink)

Peroxisomal matrix proteins are synthesized on cytosolic ribosomes and rapidly transported into the organelle by a complex machinery. The data gathered in recent years suggest that this machinery operates through a syringe-like mechanism, in which the shuttling receptor PEX5 − the “plunger” − pushes a newly synthesized protein all the way through a peroxisomal transmembrane protein complex − the “barrel” − into the matrix of the organelle. Notably, insertion of cargo-loaded receptor into the “barrel” is an ATP-independent process, whereas extraction (...) of the receptor back into the cytosol requires its monoubiquitination and the action of ATP-dependent mechanoenzymes. Here, we review the main data behind this model. The peroxin PEX5 is the peroxisomal matrix protein receptor. It shuttles between the cytosol and the organelle membrane, where it gets inserted into the docking/translocation module, thus pushing the cargo-protein into the peroxisome lumen. Resetting the system involves PEX5 monoubiquitination and its extraction from the membrane by the AAA-ATPases, PEX1/PEX6. (shrink)