5,931 research outputs found
Experimental precision in corn trials using the Papadakis method Precisão experimental dos ensaios de milho pelo método de Papadakis
The objective of this work was to verify whether the use of the Papadakis method in competing corn hybrid trials would lead to modifications in the validity of assumptions for the mathematical model of variance analysis and for experimental precision indicators. To achieve this, corn-grain-yield data from 25 competing corn hybrid trials, performed in a design of complete randomized blocks, were examined. Each trial entailed verification of assumptions, variance analysis, hypothesis tests, statistics to identify experimental precision, and analysis using the Papadakis method. This method improves experimental precision indicators. The assumptions were valid for both analysis types (without Papadakis and with Papadakis). Mean figures for the Fasoulas differentiation index increased from 8.5 to 20.7 and selective precision rose from 0.82 to 0.92. Trials with three repetitions analyzed using the Papadakis method enabled the identification of superior corn hybrids in relation to grain yield, with 86.5% precision. To maintain the same precision in conventional analysis, four times the number of repetitions would be necessary.Objetivou-se, no trabalho, verificar se há modificações em relação ao atendimento dos pressupostos do modelo matemático da análise de variância e indicadores de precisão experimental, com a aplicação do método de Papadakis, em ensaios de competição de híbridos de milho. Para isso, foram usados os dados de produtividade de grãos de milho de 25 ensaios de competição de híbridos, conduzidos no delineamento blocos completos ao acaso. Em cada ensaio, foram realizadas: a verificação dos pressupostos, a análise de variância, os testes de hipóteses, estatísticas para identificação da precisão experimental e a análise pelo método de Papadakis. O método de Papadakis melhora os indicadores de precisão experimental. Os pressupostos não foram violados para os dois métodos de análise (sem Papadakis e com Papadakis). A média do índice de diferenciação de Fasoulas aumentou de 8,5 para 20,7 e a acurácia seletiva de 0,82 para 0,92. Ensaios com três repetições analisados com o método de Papadakis possibilitam a identificação de híbridos superiores de milho em relação à produtividade de grãos, com 86,5% de precisão. Para manter a mesma precisão na análise usual seria necessário o quádruplo do número de repetições
Papadakis, Spiros, [No Service Number]
This record was harvested from a previous catalogue system and will be withdrawn in 2025. Information in this record may be superseded or incomplete. Visit this record in UMA's new catalogue at: https://archives.library.unimelb.edu.au/nodes/view/409365Surname: PAPADAKIS. Given Name(s) or Initials: SPIROS. Military Service Number or Last Known Location: [No Registration Number]. Missing, Wounded and Prisoner of War Enquiry Card Index Number: 1302.224809
Item: [2016.0049.41636] "Papadakis, Spiros, [No Service Number]
Underwater Noise Generated By Offshore Pile Driving: A Pile-Soil-Water Vibroacoustic Model Based On A Mode Matching Method
In this paper, a pile-water-soil model is developed for the prediction of sound generated due to impact piling. The complete model consists of two modules: i) a near-source module aiming at the accurate description of the pile-water-soil interaction together with the sound generation and propagation in the vicinity of the pile; and ii) a far-from-source module aiming at the propagation of the wave field at larger distances. The input to the far-from-source module is provided by the near-source module through a boundary integral formulation.Offshore EngineeringDynamics of StructuresEngineering Structure
PAPADAKIS NEAREST NEIGHBOR ANALYSIS OF YIELD IN AGRICULTURAL EXPERIMENTS
Papadakis analysis, originally proposed by Papadakis in 1937 belongs to a larger class of methodologies called the nearest neighbor analysis which is primarily based on the fact that plots in close proximity ( neighbors ) are exposed to similar environmental conditions and therefore, for a given plot, information from its neighboring plots could be used for adjustment of its response for spatial variability. The basic theory behind the application of Papadakis methodology to field trials is relatively simple. It is based on an analysis of covariance where the covariate is an index of fertility environment), and the response is some observable trait (e.g., grain yield), which is adjusted up or down to reflect the effect due to spatial variability. There have been several references in the literature to application of Papadakis methodology to field trials where the analysis is routinely carried out on data coming from a replicated design within a testing location. The application that is presented here is an exception to the rule in that the analysis is conducted on multi-location data with single replication per location. In plant breeding industry, a recent trend has been to move towards one-replicate testing system to maximize the coverage of the testing environments. Note that for a one-replicate test, no design such as a Lattice, can be used for adjustment of the observations for spatial variability. We start with describing the theory and methodology behind the proposed Papadakis analysis for multilocation data. Several practical problems such as impact of missing values on Papadakis covariate, choice of homogeneous vs. heterogeneous slope coefficient, and effect of influential observations, etc. are discussed and solutions are proposed. Finally, results from several validation studies on com yield data, including comparison to lattice adjusted plot values and ANOV A on adjusted vs. unadjusted data are presented to demonstrate the benefit from the proposed procedure
Clear cell endometrial cancer: A CTF multicentre Italian study
European Journal of Gynaecological Oncology
Volume 36, Issue 4, 2015, Pages 428-431
Clear cell endometrial cancer: A CTF multicentre Italian study (Article)
Maggino, T.a , Zola, P.b, Sartori, E.c, Fuso, L.d, Papadakis, C.a, Gadducci, A.e, Landoni, F.f
a Department of Obstetrics and Gynecology, Dell'Angelo Hospital, Via Paccagnella, 11, Zelarino-Venice, Italy
b Department of Gynecologic Oncology, University of Turin, Turin, Italy
c Obstetrics and Gynecology Institute, University of Brescia, Brescia, Italy
View additional affiliations
View references (23)
Abstract
Endometrial clear cell carcinoma (CCC) is a rare entity and only accounts for 1-6% of all endometrial cancers. CCC is considered an aggressive subtype of endometrial cancer with worse prognosis compared with type I cancer and more frequent relapses at distant and extrapelvic sites. These characteristics require specific treatment modalities, but rarity of the disease does not allow to identify evidence based indications for therapies. Objective of the present study is to analyse a series of cases treated in a multicentre Italian setting. Materials and Methods: Sixty-five endometrial CCC were treated in the period 1990-2010 in the participating institutions. Slides of the pathological specimens were reviewed by a single pathologist of each institution and debatable cases were collegially reviewed. Clinical records were collected by a common database. Demographic, surgical pathological, and follow-up data were registered. Results: All patients received primary surgery. Stage of disease according FIGO 2009 was as follow: la: 16.9%, lb: 35.4%, 2: 9.2%, 3a: 9.2%, 3b: 3.1%, 3c: 16.9%, 4a: 3.1%, and 4b: 6.1%. Adjuvant post-operative treatment was adopted in 53.8% of cases. A relapse was detected in 29.2% of cases with a majority of extrapelvic sites (68.4%). Five-year survival rate was significantly related to stage of disease with an excellent prognosis for Stage Ia e Ib disease with a complete staging. In these cases adjuvant treatment does not show significant improvement of survival. Relapsed cases show a response rate to treatment in 26% of cases (predominantly chemotherapy). Conclusion: CCC requires extensive surgical staging. Stage I disease completely staged does not require adjuvant therapy. More advanced stages require adjuvant chemotherapy
Pollen: the Hidden Sexuality of Flowers
Fully revised 4th edition with new images and in a new format. It is the result of the shared fascination of an artist and a scientist with the perfect design of pollen grains, organisms so small that they cannot be seen without a microscope. All of this is interwoven with a dazzling array of original images by the authors, created especially for the book. In this new edition many more original illustrations have been added and the text has been fully updated. Pollen is a unique interpretation of a magical world that no other book on the subject has ever been able to achieve
Precisão experimental de ensaios de feijão analisada pelo método de Papadakis
The objective of this work was to verify whether the use of the Papadakis method in the analysis of the results of common bean cultivar trials modifies the assumptions of the mathematical model and the experimental precision indicators. Common bean yield data obtained from 26 cultivar trials carried out in randomized complete block design were used. For each trial, with or without the use of the Papadakis method, the assumptions were verified, the analysis of variance and the hypothesis tests were carried out, and statistics were calculated in order to identify experimental precision. The assumptions were not violated by either method (with or without the Papadakis method). The Fasoulas index increased from 5.9 to 13.9, and the selective accuracy from 0.82 to 0.89 with the Papadakis method. This method allowed the identification, with 80% precision, of superior common bean cultivars regarding grain yield using only four replicates, while seven replicates were necessary to maintain 80% precision in the analysis without the Papadakis method. The Papadakis method improves the indices of experimental precision and reduces the number of replicates necessary to predict the performance of common bean cultivars regarding grain yield.O objetivo deste trabalho foi verificar se o uso do método de Papadakis na análise dos resultados dos ensaios de competição de cultivares de feijão modifica os pressupostos do modelo matemático e as medidas de precisão experimental. Foram utilizados dados de produtividade de grãos de feijão de 26 ensaios de competição de cultivares, conduzidos em delineamento de blocos ao acaso. Para cada ensaio, sem e com uso do método de Papadakis, foram realizados verificação dos pressupostos, análise de variância e testes de hipóteses, e calculadas as estatísticas para identificação da precisão experimental. Os pressupostos não foram violados por nenhum dos métodos de análise (sem e com Papadakis). O índice de diferenciação de Fasoulas aumentou de 5,9 para 13,9, e a acurácia seletiva de 0,82 para 0,89, com uso do método de Papadakis. Esse método permitiu que se obtivesse 80% de precisão na identificação de cultivares de feijão superiores quanto à produtividade de grãos com uso de apenas quatro repetições; enquanto que, na análise sem uso de Papadakis, foram necessárias sete repetições para manter a precisão de 80%. O método de Papadakis melhora os índices das medidas de precisão experimental e reduz o número de repetições necessário para a predição do desempenho de cultivares de feijão, em termos de produtividade de grãos
Generating artificial light curves: revisited and updated
The production of artificial light curves with known statistical and variability properties is of great importance in astrophysics. Consolidating the confidence levels during cross-correlation studies, understanding the artefacts induced by sampling irregularities, establishing detection limits for future observatories are just some of the applications of simulated data sets. Currently, the widely used methodology of amplitude and phase randomization is able to produce artificial light curves which have a given underlying power spectral density (PSD) but which are strictly Gaussian distributed. This restriction is a significant limitation, since the majority of the light curves, e.g. active galactic nuclei, X-ray binaries, gamma-ray bursts, show strong deviations from Gaussianity exhibiting ‘burst-like’ events in their light curves yielding long-tailed probability density functions (PDFs). In this study, we propose a simple method which is able to precisely reproduce light curves which match both the PSD and the PDF of either an observed light curve or a theoretical model. The PDF can be representative of either the parent distribution or the actual distribution of the observed data, depending on the study to be conducted for a given source. The final artificial light curves contain all of the statistical and variability properties of the observed source or theoretical model, i.e. the same PDF and PSD, respectively. Within the framework of Reproducible Research, the code and the illustrative example used in this paper are both made publicly available in the form of an interactive mathematica notebook
Utilização do método de Papadakis na melhoria da qualidade experimental de ensaios com soja Use of the Papadakis method to improve soybean trial quality
O trabalho teve como objetivo verificar as modificações na análise estatística, em relação ao atendimento aos pressupostos do modelo matemático e aos diferentes indicadores de precisão, que podem ser atribuídas à aplicação do método de Papadakis, na análise dos ensaios de competição de genótipos de soja. Foram usados os resultados da produção de grãos de soja de 226 ensaios de competição de genótipos, executados no delineamento de blocos completos ao acaso. Em cada ensaio, foram realizados: a verificação dos pressupostos, a análise da variância, os testes de hipóteses e outras estatísticas para identificação da precisão. Para verificar os ganhos em precisão, os mesmos dados foram analisados pelo método de Papadakis. Os pressupostos não foram violados em nenhum dos dois métodos de análise. A média do índice de diferenciação de Fasoulas aumentou de 5 para 12,43, em blocos homogêneos, e para 13,85, em blocos heterogêneos. O coeficiente de determinação, adequado para a classificação de precisão de experimentos, foi aproximadamente 10% superior com o uso do método de Papadakis, independentemente da eficiência do uso de blocos. A eficiência do método de Papadakis independe da eficiência do uso dos blocos e permite melhorias nos indicadores de precisão experimental.The objective of this work was to verify the modifications in statistical analysis regarding the assumption fulfillment and the different precision indicators which can be attributed to the application of the Papadakis method, in the analysis of soybean grain yield experiments. The results of soybean yield of 226 trials of genotype competition, performed in a design of complete randomized blocks, were used. For each experiment, the assumptions were checked for: the variance analyses, hypothesis tests and other analysis to identify its precision. In order to verify the profit in precision, the same data were analyzed using the Papadakis method. The assumptions were adequate for both analysis types. The mean of Fasoulas differentiation index increased from 5 to 12.43, for homogeneous blocks, and to 13.85, for heterogeneous blocks. The determination coefficient, adequate to classify the precision of the experiments, was approximately 10% higher, when the Papadakis method was used, regardless the efficiency of block use. The efficiency of the Papadakis method does not depend on the efficiency of the blocks, and allows an improvement of the indicators of experimental precision
Rob Kesseler: up close
Up close is an extensive survey of Rob Kesseler's work from the past twenty five years. His practice moves easily between disciplines to engage fully with the art and science of the world around us. From ceramics to furniture and drawing to photography, Up Close presents thought-provoking and beautiful works in a creative collage, arranged thematically, mixing images and texts that have inspired him, especially the exotic forms and luscious colours of the plant world
- …
