117 research outputs found
Pork Versus Public Goods: An Experimental Study of Public Good Provision Within a Legislative Bargaining Framework
We experimentally investigate a legislative bargaining model with both public and particularistic goods. Consistent with the qualitative implications of the model: there is near exclusive public good provision in the pure public good region, in the pure private good region minimum winning coalitions sharing private goods predominate, and in the "mixed" region proposers generally take some particularistic goods for themselves, allocating the remainder to public goods. As in past experiments, proposer power is not nearly as strong as predicted, resulting in public good provision decreasing in the mixed region as its relative value increases, which is inconsistent with the theory
Le till pollinifÚre de la péninsule du Nunavik, Québec septentrionnal
Des concentrations polliniques Ă©tonnamment Ă©levĂ©es ont Ă©tĂ© notĂ©es dans le till en pĂ©riphĂ©rie du cratĂšre du Nouveau-QuĂ©bec (Richard et al., 1991; Frechette, 1994). Nous avons posĂ© l'hypothĂšse selon laquelle le till situĂ© prĂšs de la ligne de partage glaciaire est plus riche en pollen que les tills qui en sont Ă©loignĂ©s. L'hypothĂšse est ici vĂ©rifiĂ©e. En effet, le till du centre du Nunavik, prĂšs de la ligne de partage glaciaire, recĂšle des concentrations polliniques de l'ordre de ~31 000 grains/g, alors que ceux plus Ă l'est et plus Ă l'ouest ont des valeurs moyennes respectives de ~8500 grains/g et de ~6800 grains/g. Les sĂ©diments du centre du Nunavik ont pu ĂȘtre prĂ©servĂ©s d'une Ă©rosion glaciaire intense, de sorte que le pollen accumulĂ© au cours des interstadiaires et interglaciaires antĂ©rieurs a pu ĂȘtre conservĂ© puis recyclĂ©. Ă premiĂšre vue, les spectres polliniques du till de la pĂ©ninsule du Nunavik reproduisent Ă peu prĂšs la biogĂ©ographie contemporaine. Les assemblages polliniques du till plus au nord semblent ĂȘtre le reflet d'une toundra herbacĂ©e, alors que ceux du till plus au sud s'approcheraient plutĂŽt d'une reprĂ©sentation de toundra arbustive. L'analyse des composantes principales a permis de comparer les assemblages polliniques du till Ă ceux des sĂ©diments de surface des lacs environnants. Les rĂ©sultats soulignent l'absence d'analogues contemporains de mĂȘme qu'ils laissent voir des diffĂ©rences dans la rĂ©partition ou l'Ă©tendue des zones bioclimatiques prĂ©-wisconsiniennes.Exceptionally high pollen concentrations have been noted in till in the vicinity of the Nouveau-QuĂ©bec crater (Richard et al., 1991; Frechette, 1994). We have proposed as an explanation the hypothesis that till near the ice divide is polliniferous. This present hypothesis is tested in parts of the Nunavik crossed by the Payne ice divide. Close to the ice divide, till shows pollen concentrations in the order of ~31 000 grains/g whereas tills at a distance eastward and westward have mean values of 8500 grains/g and 6800 grains/g respectively. Deposits near the ice divide zone of Nunavik may have escaped significant glacial erosion and thus pollen that had accumulated during previous interstadials and interglacials may have been preserved and recycled in till. Pollen spectra of till throughout Nunavik reflects only approximately the modern biogeography, ranging from herb-tundra in the north to shrub-tundra in the south. Main components analysis has allowed comparison between till samples and neighbouring lacustrine surface sediments; based on that comparison the pollen assemblages of the till samples have no modern analogs which suggests some shifting in the distribution of the pre-Wisconsinan bioclimatic zones.Erstaunlich hohe Pollen-Konzentrationen wurdem im Till in der NĂąhe des Kraters von Nouveau-QuĂ©bec festgestellt (Richard et al., 1991; Frechette 1994). Wir haben die HypothĂšse aufgestellt, daB das nahe bei der glazialen Eisscheide gelegene Till reicher an Pollen ist, als die von ihr entfemten Tills. Die HypothĂšse wird in diesem Beitrag Ă»berprĂčft. In der Tat enthĂąlt das Till aus dem Zentrum von Nunavik nahe bei der glazialen Eisscheide Pollen-Konzentrationen der GrĂŽBenordung -31 000 Korner/g, wogegen die mehr Ăstlich und westlich gelegenen mittlere Werte von -8500 KĂŽrner/ g bzw. -6800 Korner/g haben. Die Sedimente aus dem Zentrum von Nunavik konnten vor einer intensiven glazialen Erosion bewahrt werden, so daB der wĂąhrend der vorher-gehenden lnterstadiale und Interglaziale angesammelte Pollen erhalten und wieder-verwendet werden konnte. Auf den ersten Blick entsprechen die Pollen-Spektren vom Till der Halbinsel Nunavik ungefĂ hr der heutigen Biogeographie. Die Pollen-Einheiten vom mehr nĂŽrdlichen Till scheinen eine Pflanzen-Tundra zu spiegeln, wogegen diejenigen vom sudlicheren Till eher einer Busch-Tundra gleichen. Die Analyse der Hauptbestandteile erlaubte die Polleneinheiten des Tills mit denen der OberflĂ chensedimente der umliegenden Seen zu vergleichen. Die Ergebnisse heben das Fehlen gegenwĂ rtiger Entsprechungen hervor und lassen auch Unterschiede in der Verteilung oder Ausbreitung der bioklimatischen Zonen im Vor-Wisconsinium erkennen
Pretreatment serum albumin as a predictor of cancer survival: A systematic review of the epidemiological literature
<p>Abstract</p> <p>Background</p> <p>There are several methods of assessing nutritional status in cancer of which serum albumin is one of the most commonly used. In recent years, the role of malnutrition as a predictor of survival in cancer has received considerable attention. As a result, it is reasonable to investigate whether serum albumin has utility as a prognostic indicator of cancer survival in cancer. This review summarizes all available epidemiological literature on the association between pretreatment serum albumin levels and survival in different types of cancer.</p> <p>Methods</p> <p>A systematic search of the literature using the MEDLINE database (January 1995 through June 2010) to identify epidemiologic studies on the relationship between serum albumin and cancer survival. To be included in the review, a study must have: been published in English, reported on data collected in humans with any type of cancer, had serum albumin as <it>one of the </it>or <it>only </it>predicting factor, had survival as one of the outcome measures (primary or secondary) and had any of the following study designs (case-control, cohort, cross-sectional, case-series prospective, retrospective, nested case-control, ecologic, clinical trial, meta-analysis).</p> <p>Results</p> <p>Of the 29 studies reviewed on cancers of the gastrointestinal tract, all except three found higher serum albumin levels to be associated with better survival in multivariate analysis. Of the 10 studies reviewed on lung cancer, all excepting one found higher serum albumin levels to be associated with better survival. In 6 studies reviewed on female cancers and multiple cancers each, lower levels of serum albumin were associated with poor survival. Finally, in all 8 studies reviewed on patients with other cancer sites, lower levels of serum albumin were associated with poor survival.</p> <p>Conclusions</p> <p>Pretreatment serum albumin levels provide useful prognostic significance in cancer. Accordingly, serum albumin level could be used in clinical trials to better define the baseline risk in cancer patients. A critical gap for demonstrating causality, however, is the absence of clinical trials demonstrating that raising albumin levels by means of intravenous infusion or by hyperalimentation decreases the excess risk of mortality in cancer.</p
Longitudinal study of childhood sleep trajectories and adolescent mental health problems
Abstract
Study objective
To investigate whether childhood sleep trajectories are associated with mental health symptoms such as social phobia, generalized anxiety, depression, attention deficit hyperactivity disorder (ADHD), conduct problems, and opposition at age 15.
Methods
A total of 2120 children took part in the Quebec Longitudinal Study of Child Development. Childhood sleep trajectories were computed from maternal reports at 2.5, 3.5, 4, 6, 8, 10, and/or 12 years. At age 15, 1446 adolescents filled out mental health and sleep questions. A path analysis model was assessed in the full sample.
Results
Four childhood nocturnal sleep duration trajectories were identified: (1) a short pattern (7.5%), (2) a short-increasing pattern (5.8%), (3) a 10 hours pattern (50.7%), and (4) an 11 hours pattern (36.0%). Three childhood sleep latency trajectories were found: (1) a short pattern (31.7%), (2) an intermediate pattern (59.9%), and (3) a long pattern (8.4%). Finally, two childhood wakefulness after sleep-onset trajectories were found: (1) a normative pattern (73.0%) and (2) a long pattern (27.0%). The path analysis model indicated that children following a long childhood sleep latency trajectory were more likely to experience symptoms of depression (ÎČâ
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0.06, 95% CI: 0.01 to 0.12), ADHD (ÎČâ
=â
0.07, 95% CI: 0.02 to 0.13), conduct problems (ÎČâ
=â
0.05, 95% CI: 0.00 to 0.10) and opposition (ÎČâ
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0.08, 95% CI: 0.02 to 0.13) at age 15.
Conclusions
This longitudinal study revealed that children presenting a long sleep latency throughout childhood are at greater risk of symptoms of depression, ADHD, conduct problems, and opposition in adolescence
Behavior in behavioral strategy : capturing, measuring, analyzing
Measuring behavior requires research methods that can capture observed outcomes and expose underlying processes and mechanisms. In this chapter, we present a toolbox of instruments and techniques we designed experimental tasks to simulate decision environments and capture behavior. We deployed protocol analysis and text analysis to examine the underlying cognitive processes. In combination, these can simultaneously grasp antecedents, outcomes, processes, and mechanisms. We applied them to collect rich behavioral data on two key topics in strategic management: the explorationâexploitation trade-off and strategic risk-taking. This mix of methods is particularly useful in describing actual behavior as it is, not as it should be, replacing assumptions with data and offering a finer-grained perspective of strategic decision-making
Temporal and spatial variability in stable isotope ratios of SPM link to local hydrography and longer term SPM averages suggest heavy dependence of mussels on nearshore production
Temporal changes in hydrography affect suspended particulate matter (SPM) composition and distribution in coastal systems, potentially influencing the diets of suspension feeders. Temporal variation in SPM and in the diet of the mussel Perna perna, were investigated using stable isotope analysis. The ÎŽ13C and ÎŽ15 N ratios of SPM, mussels and macroalgae were determined monthly, with SPM samples collected along a 10 km onshoreâoffshore transect, over 14 months at Kenton-on-Sea, on the south coast of South Africa. Clear nearshore (0 km) to offshore (10 km) carbon depletion gradients were seen in SPM during all months and extended for 50 km offshore on one occasion. Carbon enrichment of coastal SPM in winter (JuneâAugust 2004 and May 2005) indicated temporal changes in the nearshore detrital pool, presumably reflecting changes in macroalgal detritus, linked to local changes in coastal hydrography and algal seasonality. Nitrogen patterns were less clear, with SPM enrichment seen between July and October 2004 from 0 to 10 km. Nearshore SPM demonstrated cyclical patterns in carbon over 24-h periods that correlated closely with tidal cycles and mussel carbon signatures, sampled monthly, demonstrated fluctuations that could not be correlated to seasonal or monthly changes in SPM. Macroalgae showed extreme variability in isotopic signatures, with no discernable patterns. IsoSource mixing models indicated over 50% reliance of mussel tissue on nearshore carbon, highlighting the importance of nearshore SPM in mussel diet. Overall, carbon variation in SPM at both large and small temporal scales can be related to hydrographic processes, but is masked in mussels by long-term isotope integration
The relationships between harsh physical punishment and child maltreatment in childhood and intimate partner violence in adulthood
Short-term variability in the phytoplankton and physico-chemical variables in a high-tidal regime, BahĂa Blanca Estuary, Argentina
Synthesis and Characterization of a Poly(1,3-dithienylisothianaphthene) Derivative for Bulk Heterojunction Photovoltaic Cells
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