oalib

OALib Journal期刊

ISSN: 2333-9721

费用:99美元

投稿

匹配条件: “Palma” ,找到相关结果约1677条。
列表显示的所有文章,均可免费获取
第1页/共1677条
每页显示
Correspondence Analysis on a Space-Time Data Set for Multiple Environmental Variables  [PDF]
Palma Monica
International Journal of Geosciences (IJG) , 2015, DOI: 10.4236/ijg.2015.610090
Abstract: Applications of the multivariate technique called correspondence analysis for environmental studies are relatively new and are limited to spatial multivariate data set. In this paper, a procedure of applying correspondence analysis to a large space-time data set for multiple environmental variables is shown. In particular, nitrogen dioxide and carbon monoxide hourly concentrations measured during January 1999 at several monitored stations in a district of Northern Italy are analyzed. The procedure consists in transforming the continuous variables into categorical ones by the means of appropriate indicator variables, generating special contingency tables and applying correspondence analysis. The use of this classical multivariate technique allows the identification of important relationships among pollution levels and monitoring stations and/or relationships among pollution levels and observation times.
A versatile vector system for generating recombinant EGFP-tagged proteins in yeast  [PDF]
Francesco Palma, Laura Chiarantini
Advances in Bioscience and Biotechnology (ABB) , 2011, DOI: 10.4236/abb.2011.21003
Abstract: This paper reports a versatile egfp-tagged pFL61-based expression vector system which allows the production on yeast of homo- and heterologous proteins fused with the Enhanced Green Fluorescent Protein (EGFP) at the C-terminus. This expression system, which involves a fluorescent protein, readily allows both to verify the expression and to localize the protein in the yeast cell. The vector carries a Not I site upstream the first codon of the egfp gene. The yeast cells harbouring this plasmid emit a feeble emission compared to the fluorescence expected. Was then investigated the effect of the Not I site, located very close to the start codon, on the expression of the reporter egfp gene using northern and western blotting, fluorescence microscopy and flow cytometry. Data indicated that this palindromic site could hide the start codon so as to negatively affect translation. This aspect confers to the proposed expression system an advantage in distinguishing clones after transformation.
Floquet Eigenvectors Theory of Pulsed Bias Phase and Quadrature Harmonic Oscillators  [PDF]
Fabrizio Palma, Stefano Perticaroli
Circuits and Systems (CS) , 2012, DOI: 10.4236/cs.2012.31010
Abstract: The paper presents an analytical derivation of Floquet eigenvalues and eigenvectors for a class of harmonic phase and quadrature oscillators. The derivation refers in particular to systems modeled by two parallel RLC resonators with pulsed energy restoring. Pulsed energy restoring is obtained through parallel current generators with an impulsive characteristic triggered by the resonators voltages. In performing calculation the initial hypothesis of the existence of stable oscillation is only made, then it is verified when both oscillation amplitude and eigenvalues/eigenvectors are deduced from symmetry conditions on oscillator space state. A detailed determination of the first eigenvector is obtained. Remaining eigenvectors are hence calculated with realistic approximations. Since Floquet eigenvectors are acknowledged to give the correct decomposition of noise perturbations superimposed to the oscillator space state along its limit cycle, an analytical and compact model of their behavior highlights the unique phase noise properties of this class of oscillators.
A Generalization of Berry’s Probability Function  [PDF]
André de Palma, Soumyanetra Munshi
Theoretical Economics Letters (TEL) , 2013, DOI: 10.4236/tel.2013.35A2003
Abstract: In a multi-prize contest, we consider the space of all outcomes and define a probability on it by hypothesizing the probability of an outcome to depend on resources expended by all the players. In this probability space, we then derive the probability of an individual player winning. It turns out that this probability is a generalized Berry (1993) probability function. Specifically, when 0 weight is attached to the resources spent by the “unsuccessful players” (losers), the probability of winning of an individual player is proposed exactly by Berry (1993). Such a formulation also helps to alleviate charges against the probability function of Berrylevied by Clark and Riis (1996) in the context of sequential distribution of prizes since prizes by our very hypothesis, are awarded simultaneously.

 

?Nicho, teoría neutral, o una alternativa emergente?
Palma,Alejandro;
Ecolog?-a austral , 2010,
Abstract: one of the major interests of ecology is to understand and predict species diversity in a community. two models have historically been proposed: the niche assembly theory, based mainly on the differences of the species use of resources; and the neutral theory of biodiversity, where similarities between species, not their differences, explain the high diversity of many natural systems. there was later on a momentary agreement between scientists when it was considered that both models could generate similar patterns and intermediate models were proposed unifying both approaches. a recent proposal indicate that unification might be justified by simply considering the process of the introduction of new species by dispersion and/or speciation. nevertheless, shortly afterwards, a close to the biodiversity neutral model was proposed, where species co-occur in a community not because, but in spite of, ecological differences, and which seems to be the best predicting approach considering existing empirical data. despite these efforts, controversies on the basic concepts of current models and their relationship with empirical evidence make necessary their re-evaluation, to include other important components like species turnover. this revision suggests that extension of the current models or new proposals (if necessary), including and assessing the impact of new components in current models, will allow us to understand and predict more accurately diversity and community composition, its maintenance and changes over time and spatial scale.
Arc-to-arc mini-sling 1999: a critical analysis of concept and technology
Palma, Paulo;
International braz j urol , 2011, DOI: 10.1590/S1677-55382011000200012
Abstract: purpose: the aim of this study was to critically review the arc-to-arc mini-sling (palma's technique) a less invasive mid-urethral sling using bovine pericardium as the sling material. materials and methods: the arc-to-arc mini-sling, using bovine pericardium, was the first published report of a mini-sling, in 1999. the technique was identical to the "tension-free tape" operation, midline incision and dissection of the urethra. the atfp (white line) was identified by blunt dissection, and the mini-sling was sutured to the tendinous arc on both sides with 2 polypropylene 00 sutures. results: the initial results were encouraging, with 9/10 patients cured at the 6 weeks post-operative visit. however, infection and extrusion of the mini-sling resulted in sling extrusion and removal, with 5 patients remaining cured at 12 months. conclusion: the arc-to-arc mini-sling was a good concept, but failed because of the poor technology available at that time. further research using new materials and better technology has led to new and safer alternatives for the management of stress urinary incontinence.
Trayectorias sexuales, preventivas y sociales en el embarazo no previsto de los segmentos juveniles en Chile
Palma,Irma;
Ultima década , 2010, DOI: 10.4067/S0718-22362010000200006
Abstract: the article investigates unexpected pregnancies in juvenile segments within the chilean society. it is oriented to understand its magnitude and social configuration, to include/understand its relation with the head-end process in the active sexuality and structuring of the sexual and preventive trajectories; and to explore the way in which this is used to express specific configurations of the social relations of generic and social stratification. use of the fifth national survey of youth, made possible by the national institute of youth in 2006.
MéXICO: ENTRE LA VIOLENCIA Y LA CONSOLIDACIóN DEL SISTEMA DE PARTIDOS
PALMA,ESPERANZA;
Revista de ciencia política (Santiago) , 2010, DOI: 10.4067/S0718-090X2010000200011
Abstract: the year 2009 was particularly relevant for méxico. the most outstanding events were increasing of the so-called narco-violence, caused by inter-drug cartels war for controlling territory, and between the government and the cartels, economic crisis, and local and mid-term elections that elected 500 deputies of the legislature. while violence has escalated in some states, the party system has become a consolidated one; three parties size 90% of the national vote and of the seats in congress and electoral processes took place in a normal and institutional manner, a very different situation from the 2006 turbulent presidential election. one of the most important outcomes of these elections was the electoral recovery of the partido revolucionario institucional and the electoral erosion of the ruling party, partido acción nacional, and the partido de la revolución democrática.
Las nuevas generaciones de mujeres, el embarazo no previsto, las edades y la segmentación social en la sociedad chilena
Palma,Irma;
Revista médica de Chile , 2012, DOI: 10.4067/S0034-98872012000300006
Abstract: background: unpredictedpregnancy is an evolution of the concepts undesired and unplanned pregnancy. it is more common among vulnerable strata of our society and related to lack of education. aim: to explore the prevalence and social concomitants of unpredicted pregnancy among young women. material and methods: analysis of the databases of the sixth national youth survey carried out by the instituto nacional de la juventud in chile during 2009. the universe corresponds to 7570 participants aged between 15 and 29 years, of both genders. results: unpredicted pregnancy occurred in 43% of sexually active surveyed women. it was more common among women with a lower educational level and those aged 15 to 24 years, especially during the onset of active sexual life. there was also an inverse relationship between the degree of education, the use of contraception and the age when sexual activity starts. conclusions: unpredicted pregnancy is frequent among teenagers and more common among less educated individuals. the frequency of use of contraception is associated in greater measure to the degree of education rather than the age of onset of sexual activity.
Neurocirugía y medicina nuclear Neurosurgery and Nuclear Medicine
álvaro Palma
Revista Chilena de Neuro-Psiquiatría , 2001,
Abstract:
第1页/共1677条
每页显示


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.