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Meaningful Data (meaningful + data)

Distribution by Scientific Domains

Medical Sciences	50%

Selected Abstracts

Is Semantic Information Meaningful Data?

PHILOSOPHY AND PHENOMENOLOGICAL RESEARCH, Issue 2 2005
LUCIANO FLORIDI
There is no consensus yet on the definition of semantic information. This paper contributes to the current debate by criticising and revising the Standard Definition of semantic Information (SDI) as meaningful data, in favour of the Dretske-Grice approach: meaningful and well-formed data constitute semantic information only if they also qualify as contingently truthful. After a brief introduction, SDI is criticised for providing necessary but insufficient conditions for the definition of semantic information. SDI is incorrect because truth-values do not supervene on semantic information, and misinformation (that is, false semantic information) is not a type of semantic information, but pseudo-information, that is not semantic information at all. This is shown by arguing that none of the reasons for interpreting misinformation as a type of semantic information is convincing, whilst there are compelling reasons to treat it as pseudo-information. As a consequence, SDI is revised to include a necessary truth-condition. The last section summarises the main results of the paper and indicates some interesting areas of application of the revised definition. [source]

Population Variability and Extinction Risk

CONSERVATION BIOLOGY, Issue 6 2000
John A. Vucetich
We resolve this conflict by attributing negative measured relationships to a statistical artifact that arises because PV tends to be underestimated for populations with short persistence. Such populations do not go extinct quickly as a consequence of low intrinsic variability; instead, the measured variability is low because they go extinct so quickly. Consequently, any underlying positive relationship between PV and ER tends to be obscured. We conducted a series of analyses to evaluate this claim. Simulations showed that negative measured relationships are to be expected, despite an underlying positive relationship. Simulations also identified properties of data, minimizing this bias and thereby permitting meaningful analysis. Experimental data on laboratory populations of a bruchid beetle (Callosobruchus maculatus) supported the simulation results. Likewise, with an appropriate statistical approach (Cox regression on untransformed data), reanalysis of a controversial data set on British island bird populations revealed a significant positive association between PV and ER (p = 0.03). Finally, a similar analysis of time series for naturally regulated animal populations revealed a positive association between PV and quasiextinction risk (p < 0.01). Without exception, our simulation results, experimental findings, reanalysis of published data, and analysis of quasiextinction risk all contradict previous reports of negative or equivocal relationships. Valid analysis of meaningful data provides strong evidence that increased population variability leads to increased extinction risk. Resumen: Los modelos poblacionales generalmente predicen un mayor riesgo de extinción (ER) al aumentar la variabilidad poblacional ( PV ,), a pesar de ello, algunas pruebas empíricas han proporcionado resultados contradictorios. Nosotros hemos resuelto este conflicto mediante la atribución de mediciones de relaciones negativas a un producto estadístico que surge debido a que la PV tiende a ser subestimada para poblaciones de persistencia corta. Estas poblaciones no se extinguen rápidamente como resultado de una variabilidad intrínseca baja; por lo contrario, la variabilidad medida es baja debido a que las poblaciones se extinguen tan rápidamente. Consecuentemente, cualquier relación positiva subyacente entre la PV y el ER tienden a ser opacadas. Llevamos a cabo una serie de análisis para evaluar este argumento. Las simulaciones mostraron que las relaciones negativas medidas son de esperarse, a pesar de una relación positiva subyacente. Las simulaciones también identificaron propiedades de los datos que minimizan este sesgo y por lo tanto permiten un análisis significativo. Los datos experimentales en poblaciones de laboratorio de un coleóptero bruchidae (Callosobruchus maculatus) respaldan los resultados de las simulaciones. De la misma manera, el uso de una técnica estadística adecuada (por ejemplo, la regresión Cox en datos sin transformar), usada en la repetición del análisis de un juego de datos controvertidos de poblaciones de aves de la Isla Británica reveló una asociación positiva significativa entre la PV y el ER (p = 0.03). Finalmente, un análisis similar de series de tiempo para poblaciones de animales reguladas de manera natural revelaron una asociación positiva entre la PV y el riesgo de cuasi-extinción (p < 0.01). Sin excepciones, nuestros resultados de simulaciones, los resultados experimentales, la repetición del análisis de datos publicados, y el análisis de riesgo de cuasi-extinción contradicen informes previos de relaciones negativas o equívocas. Los análisis válidos de datos significativos proveen una evidencia sólida de que los incrementos en la variabilidad poblacional conducen a un incremento en el riego de extinción. [source]

Biofilms in the Edentulous Oral Cavity

JOURNAL OF PROSTHODONTICS, Issue 5 2008
Amit Sachdeo BDS, DMSc
Abstract Purpose: The oral cavity presents numerous surfaces for microbial colonization. These surfaces produce biofilms of differing complexities unique to each individual. Several studies have looked at biofilms in dentate patients. There has been limited research regarding biofilms on dentures or soft tissues of edentulous patients. The purpose of the present investigation was to provide meaningful data describing microbial ecological relationships in the oral cavity of edentulous patients and to evaluate the microbiota on hard and soft tissue surfaces and saliva in edentulous patients wearing complete dentures. Materials and Methods: Sixty-one edentulous subjects with complete maxillary and mandibular dentures were recruited. "Supragingival" biofilm samples were taken from 28 denture teeth for each subject. Biofilm samples were also taken from the dorsal, lateral, and ventral surfaces of the tongue, floor of mouth, buccal mucosa, hard palate, vestibule/lip, "attached gingiva," and saliva. Samples were individually analyzed for their content of 41 bacterial species using checkerboard DNA,DNA hybridization. Levels and proportions of each species were determined for every sample location. Results: Periodontal pathogens such as Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis were clearly present in the samples from the edentulous subjects. Microbial profiles in samples from the soft tissue surfaces differed among site locations. Samples from the dorsum of the tongue exhibited the highest bacterial counts followed by the "attached gingiva" and the lateral surfaces of the tongue, while the lowest mean counts were found in samples from the buccal mucosa and labial vestibules. Using cluster analysis of the proportions of the test species, three clusters were formed. The first cluster comprised saliva, supragingival plaque, and the lateral and dorsal surfaces of the tongue. The second cluster comprised the other six soft tissue surfaces. Species on the denture palate formed a third cluster. Conclusions: One of the major findings in this study was the detection of periodontal pathogens, A. actinomycetemcomitans and P. gingivalis, in the edentulous subjects, as these species were thought to disappear after removal of all natural teeth. This finding has implications regarding future dental treatment and the general health of individuals. Distinct patterns of microbial colonization were seen on the different soft tissue surfaces. Thus, this investigation provided the first step in defining the organisms that are associated with edentulous patients on both soft (mucosa) and hard surfaces (denture). The study also provided meaningful data that described microbial ecological relationships in the oral cavity of edentulous subjects. The authors believe that this study is the first comprehensive assessment of the microbiota in the complete denture-wearing subject. [source]

Imaging and analysis of 3-D structure using a dual beam FIB

MICROSCOPY RESEARCH AND TECHNIQUE, Issue 3 2007
D. McGrouther
Abstract The application of focused ion beam instrumentation in the generation of three-dimensional microstructural data is described. The methodologies used to acquire and manipulate this data are explained, and the technique is illustrated by a number of examples from the material sciences. The limitations of this method, and practical pointers to the generation of meaningful data, are also discussed. Microsc. Res. Tech., 2007. © 2007 Wiley-Liss, Inc. [source]

Is Semantic Information Meaningful Data?

Characteristics of patients with coronary artery disease and hypertension: A report from INVEST

CLINICAL CARDIOLOGY, Issue S5 2001
Serap Erdine M.D.
Abstract In all, 22,599 patients with coexisting hypertension and coronary artery disease (CAD) from around the world are enrolled in the INternational VErapamil SR/trandolapril STudy (INVEST). As a result, much will be learned regarding the use of treatment strategies using verapamil SR and atenolol with and without trandolapril and/or hydrochlororthiazide in patients with hypertension and CAD, all of whom are at high risk for adverse cardiovascular outcomes. This trial will provide meaningful data on optimal treatment strategies for hypertension, especially among patients who are elderly, have diabetes, have left ventricular hypertrophy, or who are dyslipidemic. This trial will be the first to use Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure (JNC VI) guidelines as blood pressure goals to determine the relative benefits of a calcium antagonist versus a beta-blocker strategy in reducing morbidity and mortality. In addition, women and Hispanic patients participating in INVEST will provide the largest controlled experience in the management of hypertensive patients with CAD, facilitating the development of future guidelines. [source]