29 research outputs found
Estimation of Peaked Densities Over the Interval [0,1] Using Two-Sided Power Distribution: Application to Lottery Experiments
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Assessing heat-related health risk in Europe via the Universal Thermal Climate Index (UTCI)
In this work the potential of the Universal Thermal Climate Index (UTCI) as a heat-related health risk indicator in Europe is demonstrated. The UTCI is a bioclimate index that uses a multi-node human heat balance model to represent the heat stress induced by meteorological conditions to the human body. Using 38 years of meteorological reanalysis data, UTCI maps were computed to assess the thermal bioclimate of Europe for the summer season. Patterns of heat stress conditions and non-thermal stress regions are identified across Europe. An increase in heat stress up to 1°C is observed during recent decades. Correlation with mortality data from 17 European countries revealed that the relationship between the UTCI and death counts depends on the bioclimate of the country, and death counts increase in conditions of moderate and strong stress, i.e. when UTCI is above 26°C and 32°C. The UTCI’s ability to represent mortality patterns is demonstrated for the 2003 European heatwave. These findings confirm the importance of UTCI as a bioclimatic index that is able to both capture the thermal bioclimatic variability of Europe, and relate such variability with the effects it has on human health
Many Labs 5:Testing pre-data collection peer review as an intervention to increase replicability
Replication studies in psychological science sometimes fail to reproduce prior findings. If these studies use methods that are unfaithful to the original study or ineffective in eliciting the phenomenon of interest, then a failure to replicate may be a failure of the protocol rather than a challenge to the original finding. Formal pre-data-collection peer review by experts may address shortcomings and increase replicability rates. We selected 10 replication studies from the Reproducibility Project: Psychology (RP:P; Open Science Collaboration, 2015) for which the original authors had expressed concerns about the replication designs before data collection; only one of these studies had yielded a statistically significant effect (p < .05). Commenters suggested that lack of adherence to expert review and low-powered tests were the reasons that most of these RP:P studies failed to replicate the original effects. We revised the replication protocols and received formal peer review prior to conducting new replication studies. We administered the RP:P and revised protocols in multiple laboratories (median number of laboratories per original study = 6.5, range = 3?9; median total sample = 1,279.5, range = 276?3,512) for high-powered tests of each original finding with both protocols. Overall, following the preregistered analysis plan, we found that the revised protocols produced effect sizes similar to those of the RP:P protocols (?r = .002 or .014, depending on analytic approach). The median effect size for the revised protocols (r = .05) was similar to that of the RP:P protocols (r = .04) and the original RP:P replications (r = .11), and smaller than that of the original studies (r = .37). Analysis of the cumulative evidence across the original studies and the corresponding three replication attempts provided very precise estimates of the 10 tested effects and indicated that their effect sizes (median r = .07, range = .00?.15) were 78% smaller, on average, than the original effect sizes (median r = .37, range = .19?.50)
Examining the generalizability of research findings from archival data
This initiative examined systematically the extent to which a large set of archival research findings generalizes across contexts. We repeated the key analyses for 29 original strategic management effects in the same context (direct reproduction) as well as in 52 novel time periods and geographies; 45% of the reproductions returned results matching the original reports together with 55% of tests in different spans of years and 40% of tests in novel geographies. Some original findings were associated with multiple new tests. Reproducibility was the best predictor of generalizability—for the findings that proved directly reproducible, 84% emerged in other available time periods and 57% emerged in other geographies. Overall, only limited empirical evidence emerged for context sensitivity. In a forecasting survey, independent scientists were able to anticipate which effects would find support in tests in new samples
Ultrastructural changes in chloroplasts of mesophyll cells of chlorotic and prematurely yellowed leaves of Betula pendula Rothr.
The ultrastructure of chloroplasts was studied in mesophyll cells of the leaves of silver birch (Betula pendula) showing interveinal chlorosis or premature yellowing, in comparison with leaves without symptoms or exhibiting symptoms of natural senescence. The leaves were collected between May 26 to June 7 and additionally in the September 10-12 from the upper part of the crown, from increments of the past four years. No major difference in ultrastructure of chloroplasts was found between spongy and palisade mesophyll cells. The following senescencerelated changes were observed in chloroplasts of prematurely yellowed leaves and showing inteveinal chlorosis: reduced chloroplast size, degeneration of the membrane systems of thylakoids and increased electron density of plastoglobuli. The most electron dark globules (lipid droplets) were found together with starch grains in cells of spongy mesophyll of leaves showing interveinal chlorosis. Abnormal, spherical and rounded chloroplasts with electron-dark inside of thylakoids or the electron-dark stroma between thylakoids were found only in yellowed and chlorotic leaves in spring
Morphological differentiation of Primula veris L. pollen from natural and cultivated populations
Micromorphological characterisation and the comparative statistical analysis of the size of Primula veris L. pollen grains collected in three natural and three cultivated populations were done. Observations were carried out with SEM. The obtained measurements were analysed with the use of one-way ANOVA, Kruskal-Wallis Test and the Student-t Test. Pollen grains from long-styled ('pin') flower-morphs were mainly 6 colpate and from shortstyled ('thrum') flower-morphs 8 colpate. Colpi of some grains from 'thrum' flowers were 'sinuous' and 'circular', and they incised into the apocolpium zone. Ornamentation of 'pin' pollen grains was microreticulate, with lumina up to 0.8 μm wide, and for pollen grains from 'thrum' flowers was reticulate and eureticulate with lumina 1.1-1.7 μm wide. In lumina of mesocolpium area some free columellae were observed. Pollen grains from 'thrum' flower-morphs were more variable in size, both in natural and in cultivated populations, than grains from 'pin' flower-morphs. The differences in mean length (P) and breadth (E) of pollen grains from 'thrum' flowers collected in cultivated populations were statistically important (FP = 3.154 for the critical F005 = 3.098; K-We = 7.469 for the critical Test value α=005 = 5.991). Pollen grains from 'thrum' flowers were bigger when coming from plants growing in natural populations (tE = 2.784 for the critical Test value α=005 = 2.001)
Forecast changes for heat and cold stress in Warsaw in the 21st century, and their possible influence on mortality risk
This paper presents the results of research dealing with forecast changes
in the frequency of occurrence of heat and cold stress in Warsaw (Poland) in the years
2001–2100, and the possible influence these may exert on mortality risk. Heat and cold stress
were assessed by reference to the Universal Thermal Climate Index (UTC I), for which values
were calculated using meteorological data derived from the MPI-M-RE MO regional climate
model, at a with spatial resolution of 25 × 25 km. The simulations used boundary conditions
from the EC HAMP5 Global Climate Model, for SRES scenario A1B. Predictions of mortality
rate were in turn based on experimental epidemiological data from the period 1993–2002.
Medical data consist of daily numbers of deaths within the age category above 64 years
(TM64+). It proved possible to observe a statistically significant relationship between UTC I
and mortality rates, this serving as a basis for predicting possible changes in mortality in the
21st century due to changing conditions as regards heat and cold stress