A wider Europe? The view from Russia, Belarus and Ukraine

On the evidence of national surveys conducted between 2000 and 2006, there is a declining sense of European self-identity in the three Slavic post-Soviet republics of Russia, Belarus and Ukraine. Attitudes towards the European Union and the possibility of membership are broadly supportive, but with a substantial proportion who find it difficult to express a view, and substantial proportions are poorly informed in comparison with the general public in EU member or prospective member countries. Those who are better informed are more likely to favour EU membership and vice versa. Generally, socioeconomic characteristics (except for age and region) are relatively poor predictors of support for EU membership as compared with attitudinal variables. But ‘Europeanness’ should not be seen as a given, and much will depend on whether EU member countries emphasize what is common to east and west or establish ‘new dividing lines’ in place of those of the cold war

Dark Energy and Gravity

I review the problem of dark energy focusing on the cosmological constant as the candidate and discuss its implications for the nature of gravity. Part 1 briefly overviews the currently popular `concordance cosmology' and summarises the evidence for dark energy. It also provides the observational and theoretical arguments in favour of the cosmological constant as the candidate and emphasises why no other approach really solves the conceptual problems usually attributed to the cosmological constant. Part 2 describes some of the approaches to understand the nature of the cosmological constant and attempts to extract the key ingredients which must be present in any viable solution. I argue that (i)the cosmological constant problem cannot be satisfactorily solved until gravitational action is made invariant under the shift of the matter lagrangian by a constant and (ii) this cannot happen if the metric is the dynamical variable. Hence the cosmological constant problem essentially has to do with our (mis)understanding of the nature of gravity. Part 3 discusses an alternative perspective on gravity in which the action is explicitly invariant under the above transformation. Extremizing this action leads to an equation determining the background geometry which gives Einstein's theory at the lowest order with Lanczos-Lovelock type corrections. (Condensed abstract).Comment: Invited Review for a special Gen.Rel.Grav. issue on Dark Energy, edited by G.F.R.Ellis, R.Maartens and H.Nicolai; revtex; 22 pages; 2 figure

Ecological Invasion, Roughened Fronts, and a Competitor's Extreme Advance: Integrating Stochastic Spatial-Growth Models

Both community ecology and conservation biology seek further understanding of factors governing the advance of an invasive species. We model biological invasion as an individual-based, stochastic process on a two-dimensional landscape. An ecologically superior invader and a resident species compete for space preemptively. Our general model includes the basic contact process and a variant of the Eden model as special cases. We employ the concept of a "roughened" front to quantify effects of discreteness and stochasticity on invasion; we emphasize the probability distribution of the front-runner's relative position. That is, we analyze the location of the most advanced invader as the extreme deviation about the front's mean position. We find that a class of models with different assumptions about neighborhood interactions exhibit universal characteristics. That is, key features of the invasion dynamics span a class of models, independently of locally detailed demographic rules. Our results integrate theories of invasive spatial growth and generate novel hypotheses linking habitat or landscape size (length of the invading front) to invasion velocity, and to the relative position of the most advanced invader.Comment: The original publication is available at www.springerlink.com/content/8528v8563r7u2742

The Number of Genomic Copies at the 16p11.2 Locus Modulates Language, Verbal Memory, and Inhibition.

Deletions and duplications of the 16p11.2 BP4-BP5 locus are prevalent copy number variations (CNVs), highly associated with autism spectrum disorder and schizophrenia. Beyond language and global cognition, neuropsychological assessments of these two CNVs have not yet been reported. This study investigates the relationship between the number of genomic copies at the 16p11.2 locus and cognitive domains assessed in 62 deletion carriers, 44 duplication carriers, and 71 intrafamilial control subjects. IQ is decreased in deletion and duplication carriers, but we demonstrate contrasting cognitive profiles in these reciprocal CNVs. Deletion carriers present with severe impairments of phonology and of inhibition skills beyond what is expected for their IQ level. In contrast, for verbal memory and phonology, the data may suggest that duplication carriers outperform intrafamilial control subjects with the same IQ level. This finding is reminiscent of special isolated skills as well as contrasting language performance observed in autism spectrum disorder. Some domains, such as visuospatial and working memory, are unaffected by the 16p11.2 locus beyond the effect of decreased IQ. Neuroimaging analyses reveal that measures of inhibition covary with neuroanatomic structures previously identified as sensitive to 16p11.2 CNVs. The simultaneous study of reciprocal CNVs suggests that the 16p11.2 genomic locus modulates specific cognitive skills according to the number of genomic copies. Further research is warranted to replicate these findings and elucidate the molecular mechanisms modulating these cognitive performances

Efeito da Gliricidia sepium sobre nutrientes do solo, microclima e produtividade do milho em sistema agroflorestal no Agreste Paraibano.

Gliricidia sepium é uma leguminosa arbórea que tem sido utilizada em sistemas em aléias no semi-árido nordestino por apresentar bom desenvolvimento em condições de estresse hídrico. Entretanto, há pouca informação disponível sobre o efeito da introdução dessa espécie nos agroecossistemas da região. No presente estudo, objetivou-se avaliar a influência da distância de plantas de Gliricidia sepium sobre características da cultura do milho e do solo e microclima no Agreste Paraibano. O estudo foi realizado no município de Esperança (PB), em área de 0,5 ha, onde, em 1996, foram plantadas fileiras de G. sepium espaçadas 6 m entre si e com 1 m entre as árvores. Nesta área, em 2002, foram delimitadas quatro parcelas de 6 x 8 m e, em cada parcela, foi estabelecido um transeto perpendicular às fileiras de árvores com três posições de amostragem: (1) nas fileiras de árvores (0 m); (2) a 1 m das fileiras de árvores, e (3) a 3 m de distância das fileiras de árvores. O delineamento experimental utilizado foi em blocos casualizados com quatro repetições. A massa seca de folhedo caído embaixo da fileira de árvores foi de 1.390 kg ha-1 e diminuiu, gradativamente, para 270 kg ha-1 a 3 m de distância das árvores. As concentrações de P, K e matéria orgânica leve (MOL) embaixo das árvores foram maiores do que a 1 e 3 m de distância das fileiras. As médias mensais das temperaturas mínimas do ar e do solo embaixo e a 3 m das árvores foram similares. Entretanto, as médias mensais das temperaturas máximas do solo e do ar foram de 6 e 2 °C mais altas a 3 m das árvores, respectivamente, ao longo do período de estudo. A umidade do solo foi significativamente menor embaixo das árvores do que a 1 e 3 m de distância. O milho produziu mais grãos e palha e acumulou mais nutrientes nas posições mais próximas das fileiras de G. sepium

Measurement of the Charged Multiplicities in b, c and Light Quark Events from Z0 Decays

Average charged multiplicities have been measured separately in $b$, $c$ and light quark ($u,d,s$) events from $Z^0$ decays measured in the SLD experiment. Impact parameters of charged tracks were used to select enriched samples of $b$ and light quark events, and reconstructed charmed mesons were used to select $c$ quark events. We measured the charged multiplicities: $\bar{n}_{uds} = 20.21 \pm 0.10 (\rm{stat.})\pm 0.22(\rm{syst.})$, $\bar{n}_{c} = 21.28 \pm 0.46(\rm{stat.}) ^{+0.41}_{-0.36}(\rm{syst.})$ $\bar{n}_{b} = 23.14 \pm 0.10(\rm{stat.}) ^{+0.38}_{-0.37}(\rm{syst.})$, from which we derived the differences between the total average charged multiplicities of $c$ or $b$ quark events and light quark events: $\Delta \bar{n}_c = 1.07 \pm 0.47(\rm{stat.})^{+0.36}_{-0.30}(\rm{syst.})$ and $\Delta \bar{n}_b = 2.93 \pm 0.14(\rm{stat.})^{+0.30}_{-0.29}(\rm{syst.})$. We compared these measurements with those at lower center-of-mass energies and with perturbative QCD predictions. These combined results are in agreement with the QCD expectations and disfavor the hypothesis of flavor-independent fragmentation.Comment: 19 pages LaTex, 4 EPS figures, to appear in Physics Letters

Sex Segregation and Salary Structure in Academia

This article reports a study of aggregate unit salary levels, within a major research university. We analyze these salary levels, as they are influenced by unit sex composition, and modified by unit attainment levels—where unit refers to the departments, colleges and schools, and other academic divisions of the university. We investigate three central issues of sex and salary, previously overlooked in salary studies of academic employees: Do high proportions of women depress men's unit salary levels ("competition" hypothesis)? Are women's salary levels higher in male-dominated, and lower in female-dominated, units ("concentration" hypothesis)? Are men salary-compensated for working with women ("compensation" hypothesis)? The findings support none of these hypotheses. Rather, the relationship between unit sex composition and salary rests upon the connection between units' composition and attainment levels.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/69126/2/10.1177_073088848100800103.pd

Evidence of Color Coherence Effects in W+jets Events from ppbar Collisions at sqrt(s) = 1.8 TeV

We report the results of a study of color coherence effects in ppbar collisions based on data collected by the D0 detector during the 1994-1995 run of the Fermilab Tevatron Collider, at a center of mass energy sqrt(s) = 1.8 TeV. Initial-to-final state color interference effects are studied by examining particle distribution patterns in events with a W boson and at least one jet. The data are compared to Monte Carlo simulations with different color coherence implementations and to an analytic modified-leading-logarithm perturbative calculation based on the local parton-hadron duality hypothesis.Comment: 13 pages, 6 figures. Submitted to Physics Letters