An overview of study designs

The numbers of clinical trials have increased exponentially over the last decade, amplifying the pressure to select an appropriate study design to obtain reliable and valid evidence. The ability to find, critically appraise and use evidence to develop new interventions is fundamental to evidence-based medicine. Different study designs have their own advantages and disadvantages, and provide different evidentiary value. This article provides an overview of clinical trials, illustrating that, ultimately, the study design chosen needs to meet experimental and funding limitations, while minimising error

The structure of Maltese: A study in mixed grammar and vocabulary.

Maltese is a separate language resulting from the interaction and fusion of North-African Arabic Siculo-Italian, covering two different cultural strata. The Arabic element in Maltese very often corresponds to the Anglo-Saxon in English, while the Romance loans correspond to the Norman-French element. Also as in English, the primitive linguistic stratum is confined mainly to the description of the obvious facts of Nature and the Individual's reactions to them while the abstract and progressive vocabulary of the intelligentsia belongs to later times. The result of this fusion is a mixed grammar and vocabulary as we shall show when studying the structure of spoken Maltese. In order to be able to distinguish the two elements, we have established a series of descriptive criteria that together make possible a detailed phonological analysis of the language. The thesis begins with a description of Maltese sounds, followed by Phonology, where these criteria are based on a study of the Vowels, their quantity, position and sequences; the semi vowel, the diphthongs, their position, stress, the consonants, their sequences including initial groups in phonological junction (zero vowel). In Morphology the words are studied as patterns, with particular attention to the formal arrangement of the consonants and the correlative vowels which are described in their various semantic changes with lists of examples from spoken and archaic Maltese. In both parts the two elements have been treated separately but under Semitic Maltese are treated those words which have been assimilated partially or completely to a Semitic pattern. Words which have not been so assimilated are of course treated under the head of Romance Maltese

Comparison of machine learning approaches with a general linear model to predict personal exposure to benzene

Machine learning techniques (MLTs) offer great power in analyzing complex data sets and have not previously been applied to non-occupational pollutant exposure. MLT models that can predict personal exposure to benzene have been developed and compared with a standard model using a linear regression approach (GLM). The models were tested against independent data sets obtained from three personal exposure measurement campaigns. A correlation-based feature subset (CFS) selection algorithm identified a reduced attribute set, with common attributes grouped under the use of paints in homes, upholstery materials, space heating, and environmental tobacco smoke as the attributes suitable to predict the personal exposure to benzene. Personal exposure was categorized as low, medium, and high, and for big data sets, both the GLM and MLTs show high variability in performance to correctly classify greater than 90 percentile concentrations, but the MLT models have a higher score when accounting for divergence of incorrectly classified cases. Overall, the MLTs perform at least as well as the GLM and avoid the need to input microenvironment concentrations