Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2020 ( 6 )

2019 ( 662 )

2018 ( 818 )

2017 ( 752 )

Custom range...

Search Results: 1 - 10 of 461911 matches for " A Lourens "
All listed articles are free for downloading (OA Articles)
Page 1 /461911
Display every page Item
Resensie: "Poppekas"
A Lourens
Tydskrif vir letterkunde , 2013,
Abstract: Poppekas. Deborah Steinmair. Pretoria: LAPA Uitgewers, 2012. 249 pp. ISBN: 978-0-7993-5520-8.
VATS intraoperative tattooing to facilitate solitary pulmonary nodule resection
Lourens Willekes, Cherif Boutros, Michael A Goldfarb
Journal of Cardiothoracic Surgery , 2008, DOI: 10.1186/1749-8090-3-13
Abstract: Several techniques have been described to localize peripheral pulmonary nodules, including pre-operative CT-guided tattooing with methylene blue, CT scan guided spiral/hook wire placement, and transthoracic ultrasound.As pulmonary surgeons well know, the lung and visceral pleura may appear featureless on top of a pulmonary nodule.This paper presents a rapid, direct and inexpensive approach to peripheral lung lesion resection by marking the lung parenchyma on top of the nodule using direct methylene blue injection.In two patients with peripherally located lung nodules (n = 3) scheduled for VATS, we used direct methylene blue injection for intraoperative localization of the pulmonary nodule. Our technique was the following: After finger palpation of the lung, a spinal 25 gauge needle was inserted through an existing port and 0.1 ml of methylene blue was used to tattoo the pleura perpendicular to the localized nodule.The methylene blue tattoo immediately marks the lung surface over the nodule. The surgeon avoids repeated finger palpation, while lining up stapler, graspers and camera, because of the visible tattoo. Our technique eliminates regrasping and repalpating the lung once again to identify a non marked lesion.Three lung nodules were resected in two patients. Once each lesion was palpated it was marked, and the area was resected with security of accurate localization. All lung nodules were resected in totality with normal lung parenchymal margins. Our technique added about one minute to the operative time. The two patients were discharged home on the second postoperative day, with no morbidity.VATS with intraoperative tattooing is a safe, easy, and accurate technique to streamline and efficiently resect solitary pulmonary nodules.Video-assisted thoracic surgery (VATS) has been applied over the last decade to virtually every disease process encountered in thoracic medicine [1]. Its use as a diagnostic tool in pleural and pulmonary disease is well established espec
Robust and Unbiased Variance of GLM Coefficients for Misspecified Autocorrelation and Hemodynamic Response Models in fMRI
Lourens Waldorp
International Journal of Biomedical Imaging , 2009, DOI: 10.1155/2009/723912
Abstract: As a consequence of misspecification of the hemodynamic response and noise variance models, tests on general linear model coefficients are not valid. Robust estimation of the variance of the general linear model (GLM) coefficients in fMRI time series is therefore essential. In this paper an alternative method to estimate the variance of the GLM coefficients accurately is suggested and compared to other methods. The alternative, referred to as the sandwich, is based primarily on the fact that the time series are obtained from multiple exchangeable stimulus presentations. The analytic results show that the sandwich is unbiased. Using this result, it is possible to obtain an exact statistic which keeps the 5% false positive rate. Extensive Monte Carlo simulations show that the sandwich is robust against misspeci cation of the autocorrelations and of the hemodynamic response model. The sandwich is seen to be in many circumstances robust, computationally efficient, and flexible with respect to correlation structures across the brain. In contrast, the smoothing approach can be robust to a certain extent but only with specific knowledge of the circumstances for the smoothing parameter.
Preven??o de doen?as sexualmente transmissíveis em mulheres: associa??o com variáveis sócio-econ?micas e demográficas
Jiménez, Ana Luisa;Gotlieb, Sabina Léa Davidson;Hardy, Ellen;Zaneveld, Lourens J. D.;
Cadernos de Saúde Pública , 2001, DOI: 10.1590/S0102-311X2001000100005
Abstract: sexually transmitted diseases (stds) have been a subject of discussion both among scientists and in the mass media, especially because of their association with the human immunodeficiency virus (hiv). we studied the adoption of specific protective behaviors for the prevention of stds among women, as well as the associations between these behaviors and socioeconomic and demographic variables. this was a descriptive study based on secondary data from a previous study carried out in campinas, s?o paulo state, brazil. a total of 635 women were selected using the social network ("snowball") technique. subjects were classified into four groups: adolescents and adults of upper middle and lower socioeconomic status, respectively. condoms were the std prevention method most frequently mentioned by interviewees. a negative association was observed between having a steady partner and condom use in all the groups. the main reason mentioned for not using condoms was "having a single partner and trusting him". among adolescents, a positive association was observed between schooling above the 8th grade and condom use, and a negative association was observed between age and condom use. among adults, only condom use in general was also positively associated with socioeconomic status.
Evaluation of pelt traits in Karakul sheep applying linear and threshold models
A Lourens, GJ Erasmus, SJ Schoeman, JB van Wyk, FWC Neser, MG Steyn
South African Journal of Animal Science , 1999,
Preven o de doen as sexualmente transmissíveis em mulheres: associa o com variáveis sócio-econ micas e demográficas
Jiménez Ana Luisa,Gotlieb Sabina Léa Davidson,Hardy Ellen,Zaneveld Lourens J. D.
Cadernos de Saúde Pública , 2001,
Abstract: As doen as sexualmente transmissíveis (DST) têm sido debatidas no ambiente científico e nos meios de comunica o de massa, em especial, por sua associa o a maior risco de infec o pelo Vírus da Imunodeficiência Humana (HIV). Estudou-se a ado o de comportamentos por mulheres para prote o das DST, tal como a associa o destes a variáveis sócio-econ micas e demográficas. Trata-se de estudo descritivo, com dados secundários de pesquisa feita em Campinas, S o Paulo, na qual foram entrevistadas 635 mulheres selecionadas mediante a técnica de amostragem "bola de neve". Foram classificadas em: adolescentes e adultas de status sócio-econ mico médio-alto ou baixo. Grande propor o delas n o se prevenia das DST, em particular, as de status baixo. Em todos os grupos, o condom masculino foi o método de preven o mais referido. Houve associa o negativa entre parceiro fixo e uso de condom, e a principal raz o para n o usá-lo foi "só ter um parceiro e confiar nele". Em meio às adolescentes, ocorreu associa o positiva entre escolaridade acima da oitava série e uso de condom, bem como negativa entre idade e uso desse método. Entre adultas o uso exclusivo de condom esteve, em geral, positivamente associado a status sócio-econ mico.
Dynamics of ~100-kyr glacial cycles during the early Miocene
D. Liebrand,L. J. Lourens,D. A. Hodell,B. de Boer
Climate of the Past Discussions , 2010, DOI: 10.5194/cpd-6-2741-2010
Abstract: Here, we present high-resolution stable isotope records from ODP Site 1264 in the South-Eastern Atlantic Ocean, which resolve the latest Oligocene to early Miocene (23.7–18.9 Ma) climate changes. Using an inverse modelling technique, we decomposed the oxygen isotope record into temperature and ice volume and found that the Antarctic ice sheet expanded during distinct episodes (e.g., Mi zones) of low short-term (~100-kyr) eccentricity forcing, which occur two to four long-term (400-kyr) eccentricity cycles apart. We argue that a~non-linear mechanism, such as the merging of (several) large East Antarctic ice sheets, caused the build-up of a larger ice sheet. During the termination phases of these larger ice sheets, on the contrary, we find a more linear response of ice-sheet variability to orbital forcing and climate became highly sensitive to the ~100-kyr eccentricity cycle. At the Oligocene-Miocene transition the model output indicates a decrease in Northern Hemisphere temperatures such that a small ice cap could develop on Greenland. This Supports the hypothesis of a threshold response for the development of Northern Hemisphere land ice to decreasing pCO2.
Die verdienstes en tekortkominge van ’n alsydige regsakademikus. ’n Kritiese waardering van Johan van der Vyver se bydrae tot die regswetenskap in Suid-Afrika
Lourens du Plessis
Koers : Bulletin for Christian Scholarship , 1999, DOI: 10.4102/koers.v64i2&3.498
Abstract: The merits and demerits of an all-rounder legal ac ademic. A critical appraisal of Johan van der Vyver’s contribution to legal scholarship in South Africa This article assesses the contribution of Johan van der Vyver to legal scholarship in South Africa. It does so with reference to his qualities and contributions as: all-rounder, mentor; Neo-Calvinist legal philosopher, herald of human rights, scholar and theoretician of Private Law and scholar and theoretician of Public Law. His achievement as legal academic is not merely described but also appraised. It is argued that he must primarily be seen as a Neo-Calvinist legal philosopher in the Kuyperian tradition. His work as one of three foremost academic exponents of the idea and practice of human rights in South Africa is all the more remarkable because his initial ideas were developed in an environment not particularly conducive to an endeavour of this kind. As scholar of Private Law his main contribution has been the development of the theory of subjective rights in Private Law (and in a purist vein). He is, however, criticised for a paucity of reflection on the development of a similar theory in Public Law.
Die sakelys vir wetsteksvertolking en die epog van konstitusionalisme in Suid-Afrika
Lourens du Plessis
Koers : Bulletin for Christian Scholarship , 1999, DOI: 10.4102/koers.v64i2&3.503
Abstract: The agenda for legislative-text interpretation and the epoch of constitutionalism in South Africa This article deals with the new demands that the advent of an era (or epoch) of constitutionalism places on the agenda o f statutory and constitutional interpretation(i.e. legislative or enacted law-text interpretation) in South Africa. Three central motifs guide the discussion: A self-dependent legislative text with an inherent, fixed meaning does not exist. The characteristic operational intent of the text genre limits the multifarious possible meanings of an enacted law-text. This confronts its interpreter with an inescapable responsibility to choose a particular meaning. The epoch of constitutionalism inevitably places a transformational subversion of certainties regarding statutory interpretation on the agenda of innovative legislative-text interpretation. The jurisprudential applicability of mainly three interpretative narratives is considered, namely reflective rhetoric, deconstruction and philosophical hermeneutics. First, the necessity for a new terminology is considered. Legislative-text interpretation is advanced as the appropriate term designating statutory as well as constitutional interpretation. Despite their dissimilarities, statutory texts and the constitutional text have enough in common to be grouped together as "legislative texts ”, a sub-genre of law-texts in general. Second, some of the crucial assumptions of the common-law (literalist-cumintentionalist) approach to statutory interpretation are subjected to critical scrutiny. The concept "intention of the legislature” is looked at in both an optimally positive and an optimally negative way. Third, the significance for legislative-text interpretation o f insights gleaned from contemporary philosophies o f interpretation, is considered These insights are the following: Insight 1: A standard interpretation of law texts that assumes that they are independent bearers of authority and that they derive from accepted meanings of legal concepts masks the perpetuated hegemony of dominant classes/groups/ categories in society, with an unfounded appeal to an illusory neutrality and impartiality o f the law. Insight 2: Language, as a complex system, is the source and guide of and operational space for all meaning. Insight 3: Meaning can only be meaning-in-context. Insight 4: Our pre-understanding not only shepherds our understanding but makes it possible. The deeper an assumption is hidden, the more intense and far-reaching is its effect on our understanding. Insight 5: The (possible) applica
Staatsveiligheid in teoreties-prinsi-pi le perspektief*
Lourens M. Du Plessis
Koers : Bulletin for Christian Scholarship , 1981, DOI: 10.4102/koers.v46i3.1110
Abstract: This article endeavours to delineate the need for a theoretically sound definition of state security (and law and order) and proposes such a definition taking cognisance of jurisprudential and politico theoretical givens. Relevant statutes, precedents and legal writings are considered in an attempt to trace current definitions of the concept, and it is concluded that an ample definition is still lacking within the South African context. The author proceeds to explain his own jurisprudential and politico theoretical premisses, whereafter a definition of state security is proposed and explained. In final conclusion this definition and its implications are applied to aspects of the situation in South Africa.
Page 1 /461911
Display every page Item

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