The accurate estimation of age is considered important from an ethical, legal and archaeological perspective. Among the numerous methods based on macroscopic skeletal studies for age estimation, the Suchey-Brooks (1990) method for aging from the pubic symphysis and the Buckberry and Chamberlain (2002) method for aging from the auricular surface are considered more reliable. However, both these methods have been derived from American populations. In saying this, the following study aimed to evaluate whether it is possible to accurately estimate the age-at-death from morphological age-related changes seen on the pubic symphysis and the auricular surface in a black South African population. A total of 197 individuals of both sexes utilising both left and right os coxae were investigated. Age was estimated using descriptions stipulated by Brooks and Suchey (1990) and Buckberry and Chamberlain (2002). Both methods indicated moderate to high inter-and intra-observer errors. Descriptive statistics indicated a sample distribution of predominantly middle aged individuals. Correlation coefficients, inaccuracies and bias as well as Principal Components Analysis (PCA) were calculated for both skeletal elements for both sexes and sides. Statistical analyses indicated no significant differences between sexes and sides for both the pubic symphysis and the auricular surface. When comparing accuracies of each method, inaccuracies and bias were lower in the pubic symphysis than in the auricular surface thus making the pubic symphysis a more reliable age estimator. Similarly, males indicated lower inaccuracies and bias than did females. Principal Component Analysis indicated variance between certain features found on the pubic symphysis and the auricular surface. Overall, the pubic symphysis outperformed the auricular surface, even though the method described by Buckberry and Chamberlain (2002) is considered more reliable. Further investigation of these two methods on a white South African

No description available.

Precision of determining age in ringed seals (Phoca hispida) was examined by repeated readings of undecalcified cross sections and decalcified stained longitudinal sections of mandibular canines. There appeared to be geographical differences in repeatability although this could not be tested statistically. There was no difference in repeatability between cross and stained sections. / The effect of precision on population parameters was examined. Smoothing procedures necessary to construct life tables and to do Leslie matrix calculations obscured any differences in ages between readings. Variance between readings was found to give inconsistent notions of sexual maturity. Imprecision caused little overall difference in growth curves. / Without known age animals, accuracy cannot be evaluated directly. High correlation between ages from canines from different sides of the same animal, between dentine and cementum of teeth from the same animal, and between readers examining the same sets of teeth gave an indirect suggestion of accuracy.

No description available.

No description available.

No description available.

The periodicity of formation of growth increments in the otoliths of South African sparids was validated by the oxytetracycline labelling technique. Intramuscular injections of oxytetracycline at a dosage of 250mg/kg marked the otoliths of laboratory held juvenile sparids, while a dosage range of 50 - 100mg/kg oxytetracycline, injected intramuscularly, marked adult sparids in the field. Laboratory held, larval sparid otoliths were marked by immersion for 24hrs a solution of 100-150mg/l alizarin complexone. Both daily (microstructural) and annual (macrostructural) growth increments were identified in the otoliths. The micro incremental pattern of deposition in the sparid otoliths conformed to the general pattern of otolith structure. Sparid otoliths consisted of a central opaque nucleus composed of multiple primordia. surrounding this nucleus were daily increments which decreased in width as the distance from the nucleus increased. Both check rings and subdaily increments were visible throughout the otolith. Minor environmental changes did not affect micro incremental deposition. Narrow opaque and wide hyaline annual growth zones were identified in sectioned sparid otoliths. Scanning electron microscope analysis of the annual growth zones revealed that microincrements within the opaque zone were narrowly spaced with prominent discontinuous phases. This resulted in the greater optical density and higher protein content of the zone. The hyaline zone was composed of widely spaced daily increments with prominent incremental phases accounting for the translucent nature of this zone. Opaque zone formation in the otoliths of many South African sparids was found to occur primarily during periods of reproductive activity and was shown to be indicative of slow otolith growth. The hyaline zone was formed after the spawning season, representative of fast otolith growth. The results of this study have resolved much of the controversy surrounding the rate of growth and time of formation of the opaque and hyaline growth zones in South African sparid otoliths.

No description available.

Please read the abstract/summary in the section, 00front/07back, of this document. / Dissertation (MSc (Botany))--University of Pretoria, 2006. / Plant Science / unrestricted

nÃo hà / A estimativa da idade cronolÃgica pode ser conceituada como o processo que consiste em avaliar o estÃgio de evoluÃÃo ou involuÃÃo de um organismo. O exame para estimativa da idade cronolÃgica do indivÃduo pela avaliaÃÃo dentÃria constitui uma perÃcia que pela lei do exercÃcio profissional da Odontologia pode ser realizada pelo CirurgiÃo-Dentista. Este exame corresponde a um percentual significativo dos exames realizados nos Institutos MÃdicos Legais (IML). No IML de Fortaleza â CearÃ, este percentual representa 32,4% dos exames realizados. Este estudo teve como objetivo analisar os procedimentos de estimativa da idade cronolÃgica do indivÃduo pela avaliaÃÃo dentÃria realizado no IML de Fortaleza, com embasamento nos procedimentos e mÃtodos de estimativa da idade cronolÃgica descritos na literatura. Foi realizado um levantamento bibliogrÃfico sobre o tema onde se constatou que a estimativa da idade cronolÃgica tem diversas nuances, à estudada hà bastante tempo e existem mÃtodos com resultados com alto grau de confianÃa, sendo bastante solicitada em processos policiais e judiciais. Os dados de importÃncia para a estimativa da idade pelo exame dos dentes permanentes se distribuem nas etapas de sua evoluÃÃo: mineralizaÃÃo, erupÃÃo e modificaÃÃes dentÃrias tardias. O termo DENTIÃÃO tem um sentido dinÃmico, uma vez que define uma sÃrie de fases desde o espessamento do epitÃlio da camada basal atà a perda do dente. Jà DENTADURA à estÃtico, pois define somente uma determinada fase da vida do indivÃduo: à o conjunto dos dentes naquele momento. Neste Ãltimo caso, na perÃcia para estimativa de idade examina-se a dentadura do indivÃduo naquele momento. O desenvolvimento da radiologia odontolÃgica introduziu novos mÃtodos à estimativa de idade, que aumentaram o grau de confianÃa da mesma. A inspeÃÃo direta dos dentes à o mÃtodo atualmente utilizado para realizar a estimativa da idade cronolÃgica dos indivÃduos no IML â Fortaleza. Este estudo concluiu que tais procedimentos necessitam ser complementados por exames radiolÃgicos para que os resultados sejam mais fidedignos, os quais irÃo propiciar a determinaÃÃo da idade cronolÃgica dos indivÃduos com maior acurÃcia. / The estimation of chronological age can be defined as the process that evaluates the stage of evolution or involution of a body. The age determination by a dental evaluation is a technical inspection that can be performed by a Surgeon-Dentist, in accordance with the law of dentistry practice. This examination is carried through in legal medicine institutes with high frequency. In the Institute of Legal Medicine (IML) of Fortaleza - CearÃ, this percentage is 32.4% of all examinations. This study aimed to analyze the procedures for estimation of chronological age by dental evaluation conducted in IML of Fortaleza, based on procedures and methods for estimating the chronological age as described in literature. A literature review was performed and it has demonstrated that the estimation of chronological age has different nuances, it has been studied for a long time, and there are methods with accurate results that are required in many policy and judicial court processes. The most important information for age determination by examination of permanent teeth is distributed in their evolution stages: mineralization, dental eruption and dental late alterations. The technical term DENTITION has a dynamic sense, since it defines several stages from the thickening of the epithelium of the basal layer to the dental loss. DENTURE is static, as it defines only a phase of life of the individual: it is all the teeth at that time. The development of dental radiology has introduced new methods for estimating age, which increased the age determination accuracy. The oral examination is the only method currently used to age determination in the IML - Fortaleza. This study concluded that the oral examination procedures need to be complemented by radiological examinations that show reliable results and accurate age determination.