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Morphometric Measurements (morphometric + measurement)
Selected AbstractsUltrasonographic Morphometric Measurements of Digital Flexor Tendons and Ligaments of the Palmar Metacarpal Region in Haflinger HorsesANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 4 2010S. Boehart With 2 figures and 3 tables Summary The aim of the study was to determine morphometric values of the superficial and deep digital flexor tendon, the inferior check ligament and the suspensory ligament in the palmar metacarpal region of sound Haflinger horses using ultrasonography and to assess the influence of different factors on them. The findings were compared with the literature. A total of 30 sound Haflinger mares aged 4,20 years were used. Transverse ultrasound images were obtained with an 8,10 linear MHz transducer and the cross-sectional area, the circumference and the dorsopalmar and lateromedial width were determined for each structure at six regions of interest (ROI) in both forelimbs. The coefficient of variation was <3%. The structures were compared between each other and the values of each structure at the ROIs. Age, height at the withers, body mass index, diameter of the Os metacarpale III and the circumference of the mid-metacarpal region showed significant influences on some of the parameters. Reference values for the tendons and ligaments in the palmar metacarpal region in sound Haflinger mares were obtained and the influence of different factors was tested. Description of the dimensional relationship between the structures and comparison of the data with the literature provide knowledge required for adequate veterinary care. [source] Local host ant specificity of Phengaris (Maculinea) teleius butterfly, an obligatory social parasite of Myrmica antsECOLOGICAL ENTOMOLOGY, Issue 5 2010MAGDALENA WITEK 1. Phengaris butterflies are obligatory social parasites of Myrmica ants. Early research suggested that there is a different Myrmica host species for each of the five European Phengaris social parasites, but more recent studies have shown that this was an oversimplification. 2. The pattern of host ant specificity within a Phengaris teleius metapopulation from southern Poland is reported. A combination of studying the frequency distribution of Phengaris occurrence and morphometrics on adult butterflies were used to test whether use of different host species is reflected in larval development. 3. Phengaris teleius larvae were found to survive in colonies of four Myrmica species: M. scabrinodis, M. rubra, M. ruginodis, and M. rugulosa. Myrmica scabrinodis was the most abundant species under the host plant but the percentage of infested nests was similar to other host ant species at two sites and lower in comparison to nests of M. rubra and M. ruginodis at the other two sites. Morphometric measurements of adult butterflies reared by wild colonies of M. scabrinodis and M. ruginodis showed that wing size and number of wing spots were slightly greater for adults eclosing from nests of M. ruginodis. 4. Our results suggest that P. teleius in the populations studied is less specialised than previously suggested. The results are consistent with the hypothesis that P. teleius is expected to be the least specific of the European Phengaris species, as it has the largest and best defended fourth-instar caterpillars and, as a predatory species, it spends less time in the central larval chambers of the host colonies. The fact that individuals reared by M. ruginodis had wider hind wings may suggest that P. teleius had better access to resources in M. ruginodis than in M. scabrinodis colonies. [source] Embryos of common thresher shark Alopias vulpinus in southern Brazil, South Atlantic OceanJOURNAL OF FISH BIOLOGY, Issue 1 2006P. L. Mancini Eight embryonic thresher sharks Alopias vulpinus (53·9,124 cm total length) were collected from two females caught by commercial longline off southern Brazil in September and November 2004. Morphometric measurements are provided. [source] Poster Sessions CP04: Axonal Growth and TransportJOURNAL OF NEUROCHEMISTRY, Issue 2002L. Zhou Neurotrophins support neuronal survival and axonal regeneration after injury. To test whether local expression of Neurotrophin-3 (NT-3) would elicit axonal regeneration we lesioned the corticospinal tract (CST) at the level of the hindbrain and measured the number of axons that would grow from the unlesioned CST to the contralateral side where NT-3 was over expressed at the lumbar level of the spinal cord. An adenoviral vector that carried the rat NT-3 gene and the NGF signal peptide driven by the EF1, promoter (Adv.EF-NT-3) was used. This model enabled us to test the effects of NT-3 on axonal regeneration without confounding injury processes. Biotinylated dextran amine (BDA) was injected into the rat cortex on unlesioned side to mark CST axons 10 days postlesion. Adenoviral vectors (1 × 109 pfu, Adv.EF-NT-3 or Adv.EF-LacZ) were delivered to lumbar spinal cord by retrograde transport from the sciatic nerve 4 days later. Histological examination 3 weeks later revealed that more BDA-labelled axons had grown from the unlesioned CST to the denervated side at the lumbar level. Morphometric measurements showed that a significantly larger number of BDA-labelled CST axons (p < 0.001) were present in the animals that were treated with Adv.EF-NT-3 than those treated with Adv.EF-LacZ. These data demonstrate that local expression of NT-3 will support axonal regeneration in the injured spinal cord without adverse effects and suggest that gene delivery of neurotrophins may be an effective strategy for nervous system repair after injury. Acknowledgements:, Funded by NIH Grant NS35280 and by Mission Connect of the TIRR Foundation. [source] The decline of Steller sea lions Eumetopias jubatus in Alaska: a review of the nutritional stress hypothesisMAMMAL REVIEW, Issue 1 2003A. W. TRITES ABSTRACT 1.,The decline of Steller sea lions Eumetopias jubatus in the Gulf of Alaska and Aleutian Islands between the late 1970s and 1990s may have been related to reduced availability of suitable prey. Many studies have shown that pinnipeds and other mammals suffering from nutritional stress typically exhibit reduced body size, reduced productivity, high mortality of pups and juveniles, altered blood chemistry and specific behavioural modifications. 2.,Morphometric measurements of Steller sea lions through the 1970s and 1980s in Alaska indicate reduced body size. Reduced numbers of pups born and an apparent increase in juvenile mortality rates also appear to be nutritionally based. Blood chemistry analyses have further shown that Steller sea lions in the Gulf of Alaska and Aleutian Islands area exhibited signs of an acute phase reaction, or immune reaction, in response to unidentified physical and/or environmental stress. Behavioural studies during the 1990s have not noted any changes that are indicative of an overall shortage in the quantity of prey available to lactating female sea lions. 3.,The data collected in Alaska are consistent with the hypothesis that Steller sea lions in the declining regions were nutritionally compromised because of the relative quality of prey available to them (chronic nutritional stress), rather than because of the overall quantity of fish per se (acute nutritional stress). This is further supported by captive studies that indicate the overall quality of prey that has been available to Steller sea lions in the declining population could compromise the health of Steller sea lions and hinder their recovery. [source] Effect of RGD peptide coating of titanium implants on periimplant bone formation in the alveolar crestCLINICAL ORAL IMPLANTS RESEARCH, Issue 3 2002An experimental pilot study in dogs Abstract: The aim of the present study was to analyse the effect of organic coating of titanium implants on periimplant bone formation and bone/implant contact. Three types of implants were used: (i) Ti6Al4V implants with polished surface (control 1) (ii) Ti6Al4V implants with collagen coating (control 2) (iii) Ti6Al4V implants with collagen coating and covalently bound RGD peptides. All implants had square cross-sections with an oblique diameter of 4.6 mm and were inserted press fit into trephine burr holes of 4.6 mm in the mandibles of 10 beagle dogs. The implants of five animals each were evaluated after a healing period of 1 month and 3 months, during which sequential fluorochrome labelling of bone formation was performed. Bone formation was evaluated by morphometric measurement of the newly formed bone around the implant and the percentage of implant bone contact. After 1 month there was only little bone/implant contact, varying between 2.6 and 6.7% in the cortical bone and 4.4 and 5.7% in the cancellous bone, with no significant differences between the three types of implants. After 3 months, implants with polished surfaces exhibited 26.5 and 31.2% contact in the cortical and cancellous bone, respectively, while collagen-coated implants had 19.5 and 28.4% bone contact in these areas. Implants with RGD coating showed the highest values with 42.1% and 49.7%, respectively. Differences between the surface types as such were not significant, but the increase in bone/implant contact from 1 to 3 months postoperatively was significant only in the group of RGD-coated implants (P = 0.008 and P = 0.000). The results of this pilot study thus provide only weak evidence that coating of titanium implants with RGD peptides in the present form and dosage may increase periimplant bone formation in the alveolar process. The results therefore require further verification in a modified experimental setting. Résumé Le but de l'étude présente a été d'évaluer l'effet d'un recouvrement organique des implants en titane sur la formation osseuse paro?mplantaire et le contact os/implant. Trois types d'implants ont été utilisés: 1) implants Ti6AI4V avec surface polie (contrôle 1), 2) implants Ti6AI4V avec recouvrement de collagène (contrôle 2), 3) implants Ti6aI4V avec recouvrement de collagène et des peptides RGD accrochés de manière covalente. Tous les implants avaient une section carrée avec un diamètre oblique de 4.6 mm et étaient insérés dans des trous percés à l'aide de trépans de 4.6 mm dans la mandibule de dix chiens beagle. Les implants de cinq animaux ont étéévalués après une période de guérison d'un mois et de trois mois durant laquelle un marquage fluochrome séquentiel de la néoformation osseuse a été effectué. La formation osseuse a étéévaluée par mesure morphométrique de l'os néoformé autour de l'implant et par pourcentage de contact os/implant. Après un mois, il n'y avait que peu de contact os/implant, variant entre 2.6 et 6.7% dans l'os cortical et 4.4 et 5.7% dans l'os spongieux, sans aucune différence significative entre les trois types d'implants. Après trois mois, les implants avec les surfaces polies montraient respectivement 26.5 et 31.2% d'os cortical et spongieux, tandis que les implants recouverts de collagène avaient 19.5 et 28.4% de contact osseux dans ces zones. Les implants avec le recouvrement RGD avaient les valeurs les plus importantes avec respectivement 42.1% et 49.7%. Les différences entre les types de surface n'étaient pas significatives mais l'augmentation du contact os/implant de 1 à 3 mois après l'opération n'était significative que dans le groupe RGD (P=0.008 et P=0.0000). Les résultats de cette ewtude pilote n'ont donc mis en évidence qu'une maigre preuve que les recouvrements des implants en titane par les petpides RGD sous la forme présente et le dosage présent, pouvaient augmenter la formation osseuse paro?mplantaire dans le processus alvéolaire. Ces résultats requièrent donc davantage de vérifications dans un système expérimental modifié. Zusammenfassung Es war das Ziel dieser Untersuchung, den Einfluss einer organischen Beschichtung von Titanimplantaten auf die periimplantäre Knochenformation und auf den KnochenImplantatkontakt zu analysieren. Drei Typen von Implantaten wurden verwendet: i) Ti6AI4V Implantate mit polierter Oberfläche (Kontrolle 1), ii) Ti6AI4V Implantate mit Kollagenbeschichtung (Kontrolle 2), iii) Ti6AI4V Implantate mit Kollagenbeschichtung und kovalent gebundenen RGD-Peptiden. Alle Implantate hatten einen quadratischen Querschnitt mit einem Querdurchmesser von 4.6 mm. Sie wurden in die Unterkiefer von zehn Beaglehunden in zylindrische Bohrungen mit einem Durchmesser von 4.6 mm mit Pressitz eingesetzt. Die Implantate von je funf Tieren wurden nach einer Helungszeit von einem bzw. drei Monaten ausgewertet. Während der gesamten Zeit wurden sequentielle Fluorochrommarkierungen der Knochenbildung durchgeführt. Die Knochenbildung wurde durch morphometrische Messungen des neugebildeten Knochens um die Implantate und durch Messungen der prozentualen Anteile des Knochen-/Implantatkontakts ausgewertet. Nach 1 Monat war nur wenig Knochen-/Implantatkontakt vorhanden. Er variierte zwischen 2.6 und 6.7% im kortikalen Knochen und zwischen 4.4 und 5.7% im spongiösen Knochen. Zwischen den drei Implantattypen bestanden keine signifikanten Unterschiede. Nach drei Monaten zeigten die Implantate mit polierten Oberflächen 26.5% Knochenkontakt im kortikalen bzw. 31.2% im spongiösen Knochen, während die kollagenbeschichteten Implantate 19.5% und 28.4% Knochenkontakt in diesen Regionen zeigten. Implantate mit RGD-Beschichtung zeigten mit 42.1% bzw. 49.7% die höchsten Werte. Zwischen den Oberflächentypen bestanden keine signifikanten Unterschiede. Nur in der Gruppe mit RGD-beschichteten Implantaten nahm der Knochen-/Implantatkontakt zwischen 1 bis 3 Monaten nach Chirurgie signifikant zu (P=0.008 und P=0.000). Die Resultate dieser zeigen nur mit schwacher Evidenz, dass die Beschichtung von Titanimplantaten mit RGD-Peptiden in der vorliegenden Form und Dosierung die periimplantäre Knochenformation im Alveolarkamm erhöht. Die Resultate müssen daher in einem modifizerten experimentellen Aufbau verifiziert werden. Resumen La intención del presente estudio fue analizar el efecto de la cobertura orgánica de implantes de titanio en la formación de hueso y contacto hueso/implante. Se usaron tres tipos de implantes: i) implantes de Ti6AI4V con superficie pulida (control 1), ii) implantes Ti6AI4V con cubierta de colágeno (control 2), iii) implantes de Ti6AI4V con cubierta de colágeno y péptidos RGD con unión convalente. Todos los implantes tenían secciones cuadradas con un diámetro oblicuo de 4.6 mm y se insertaron a presión en orificios trepanados de 4.6 mm en las mandíbulas de 10 perros beagle. Se evaluaron los implantes de 5 animales tras un periodo de cicatrización de un mes y tres meses los otros cinco, durante este tiempo se llevó a cabo marcado secuencial con fluorocromo de la formación de hueso. La formación de hueso se evaluó mediante mediciones morfométricas del hueso neoformado alrededor del implante y el porcentaje de contacto hueso implante. Tras 1 mes existió muy poco contacto hueso/implante variando entre 2.6 y 6.7% en el hueso cortical y 4.4 y 5.7% en el hueso esponjoso sin diferencias significativas entre los tres tipos de implantes. Tras tres meses, los implantes con superficies pulidas exhibieron un 26.5 y 31.2% en el hueso cortical y esponjoso, respectivamente, mientras que los implantes con cubiertas de colágeno tuvieron un 19.5 y un 28.4% de contacto óseo en estas áreas. Los implantes con cubiertas de RGD mostraron los valores más altos con un 42.1 y un 49.7% respectivamente. Las diferencias ente tipos de superficie como tales no fueron significativas pero el incremento de contacto hueso/implante de 1 a 3 meses tras la operación fue significativo solo en el grupo de implantes con cubierta RGD (P=0.008 y P=0.000). Los resultados de este estudio piloto aunque han mostrado solo una débil evidencia, que la cobertura de implantes de titanio con péptidos RGD en la forma y dosis presente pueden incrementar la formación de hueso periimplantario en el proceso alveolar. Los resultados, por lo tanto, requieren una posterior verificación en una situación experimental modificada. [source] Increase of learning abilities and maturation of the vertical lobe complex during postembryonic development in the cuttlefish, SepiaDEVELOPMENTAL PSYCHOBIOLOGY, Issue 2 2001Ludovic Dickel Abstract When shown prawns in a glass tube, cuttlefish quickly learn to inhibit their predatory behavior. By using a visual learning paradigm, we studied training and retention performances of cuttlefish aged from 8 to 90 days. We found an improvement in the acquisition of learning abilities during the first 2 months of life as well as an increase of 24-hr retention performance between 30 and 90 days of age. Using morphometric measurements of different lobes of the central nervous system, we correlated the emergence of these learning abilities with the postembryonic development of related nervous structures. Our results show that only the growth of the superior frontal and vertical lobes appears to be significantly correlated with the improvement of learning and long-term retention performances. Thus, as found in earlier data collected in Octopus, the vertical lobe complex of the cuttlefish seems to be involved in these learning processes. © 2001 John Wiley & Sons, Inc. Dev Psychobiol 40: 92,98, 2001 [source] Bursaphelenchus species in conifers in Europe: distribution and morphological relationshipsEPPO BULLETIN, Issue 2 2001H. Braasch The morphological relationship between European Bursaphelenchus species living in conifers was studied in order to provide key characters for their taxonomic identification. Several species have been newly described or recorded in Europe during the past few years and were morphologically investigated. Among the 28 conifer-inhabiting European species, four groups can be distinguished from each other by the number of lateral incisures, number and position of anal papillae of males and presence and size of a vulval flap of females. Two groups, each containing just one species show two and six lateral lines, respectively, whereas most Bursaphelenchus species belong to two groups, possessing either three or four incisures. Each of the last two groups can be divided into three subgroups, which can be differentiated by spicule shape, number and position of caudal papillae, presence and size of a vulval flap and some other features. A fifth group includes species with unclear group affiliation due to insufficient knowledge of their morphology. The B. xylophilus group (B. xylophilus, B. mucronatus, B. fraudulentus) with four lateral lines, unique spicule shape and characteristic position of the caudal papillae can clearly be differentiated from all other groups by morphology, also using only light microscopy. Within this group, B. xylophilus can clearly be differentiated morphologically from the other species, provided that adult specimens of both sexes are found and also provided that the round-tailed form of the species remains the only form present, as in Europe. Figures showing the important identification features of spicule shape and female tail shape are given for 28 species. A table shows the complete range of the most important morphometric measurements of these species. Data on the occurrence, host range and, as far as known, the vectors of these species were collected throughout Europe and references are given for each record. [source] Using interpubic distance for sexing manakins in the fieldJOURNAL OF FIELD ORNITHOLOGY, Issue 1 2010Chase D. Mendenhall ABSTRACT Field methods for determining the sex of birds are often limited due to morphometric overlap between sexes, intermediate plumages, seasonality, and reliance on subjective age classification. Interpubic distance, characterized in birds as the distance between the distal ends of the pubic bones, has not been formally tested as a method for determining the sex of birds, despite references among parrot breeders and the frequent use of analogous measurements in mammals. We developed a harmless and easily performed field method for measuring interpubic distance in studies involving bird capture, and compared the interpubic distances of known sex White-ruffed Manakins (Corapipo altera), Orange-collared Manakins (Manacus aurantiacus), and Blue-crowned Manakins (Lepidothrix coronata) to evaluate the possible use of this measurement to determine sex. Using interpubic distance ranges based on 85% confidence intervals where overlap existed between sexes, the sex of 92.8,100% of all manakins in our study was accurately determined with no misclassification. Interpubic distance performed better than plumage-based methods that sexed 74.0% of all individuals and misclassified 1.5%. Using linear discriminant analysis, we developed classification equations that allowed us to accurately determine the sex of all individuals with 100% accuracy using mass and interpubic distance. Additionally, we compared the interpubic distances of female White-ruffed Manakins to evaluate the potential to determine age and reproductive status. Despite an apparent relationship between interpubic distance, age and reproductive status, we concluded that interpubic distance has limited use for determining age and reproductive status due to extensive overlap (31.6,100%), but shows potential in other applications. Based on these results, we endorse the use of interpubic distance to determine the sex of manakins. We encourage further study to develop additional classification equations using different morphometric measurements and to test the efficacy of interpubic distance to determine sex in other bird species. RESUMEN Los métodos del campo para distinguir el sexo de aves son limitados a causa de traslapes de medidas mórfometricas extremas entre sexos, plumajes intermedios, diferencias temporales y/o dependencia en clasificación sujeto de la edad. Distancia interpúbica, caracterizada en aves como la distancia entre los puntos distales de los huesos púbicos, no ha sido formalmente probada como un método para distinguir el sexo de las aves, a pesar de referencias por criadores de loros y uso de métodos similares en mamíferos. Diseñamos un método del campo rápido y sencillo que no tiene riesgo del daño para sacar la distancia interpúbica en estudios que capturan aves. Comparamos la distancia interpúbica de individuos de sexo conocido de Corapipo altera, Manacus aurantiacus, y Lepidothrix coronata para probar el método. Clasificamos correctamente el sexo de 92.8,100% de todos los individuos en este estudio por rangos determinados a través de intérvalos de confianza de 85%. La distancia interpúbica funcionó mejor que un método basado en plumaje, el cual que distinguió el sexo correcto de 74.0% pero falló en clasificar el sexo de 1.5% de los individuos estudiados. Usamos el análisis de discriminación linear para determinar el poder predictivo de la distancia interpúbica, longitud del ala y masa e hicimos ecuaciones de clasificación que distinguieron sexo con un 100% de éxito usando solo masa y distancia interpúbica. Además, comparamos distancia interpúbica de las hembras de C. altera para evaluar el potencial de distinguir edad y estadio reproductivo. A pesar de existir una conexión entre distancia interpúbica, edad y estadio reproductivo, concluimos que la distancia interpúbica es limitada en el contexto de distinguir edad y estadio reproductivo por traslape extensivo (31.6,100%), pero muestra potencial en otras aplicaciones. Basados en estos resultados recomendamos el uso de distancia interpúbica como un método para distinguir sexo de pipridos. Recomendamos más investigación para crear otras ecuaciones de clasificación usando medidas mórfometricas diferentes y probar la eficacia de la distancia interpúbica para distinguir el sexo de otras especies de aves. [source] Effects of preservation on pigmentation and length measurements in larval lampreysJOURNAL OF FISH BIOLOGY, Issue 4 2006F. B. Neave The effects of two methods of preservation (fixation and storage in 10% formalin, and fixation in 10% formalin followed by storage in 95% alcohol) on pigmentation and morphometric features used for identification of larval Ichthyomyzon lampreys were analysed. Both short-term (3 weeks) and long-term (6 months) studies were conducted using digital analysis of images of fresh and preserved lampreys. Six standard morphometric lengths and 10 areas of pigmentation were analysed. All measurements were significantly affected by preservation. Preservative type affected pigmentation and morphometric characteristics differently, and characters were affected to different degrees. Multiple measurements over time showed that almost all changes occurred within 3 weeks of preservation. Regression equations allowed for accurate correction of preservation effects on morphometric measurements, but the effects on pigmentation levels were less predictable. Effects of preservation on larval lampreys need to be considered when comparing fresh and preserved specimens because they influence critical identification features. [source] Morphometric Investigation of Death by AsphyxiaJOURNAL OF FORENSIC SCIENCES, Issue 3 2009Raffaele Giorgetti M.D. Abstract:, The aim of this study was to investigate the possibility of distinguishing deaths by asphyxia from those due to natural causes by comparing morphometric measurements in lungs. The study population comprised 27 subjects: 14 cases of death by asphyxia (hanging or drowning) and 13 cases of sudden natural death. Eighty parenchyma sections were used for each subject. Data were collected by computerized image analysis. Measurements aimed at quantifying, as percentages, pulmonary parenchyma (mean values of positive-fraction areas [PFA] and their standard deviations). Subjects who died of natural causes and of drowning showed a relative internal homogeneity compared to those who hanged. Results show significant discrimination between drowned subjects and those dying of natural causes (mean of PFA p = 0.01) and between hanged and drowned subjects (SD of PFA p = 0.04). Attention must be paid to the possible role played by senile emphysema. The method is proposed as a complementary tool in forensic cases. [source] Comparison between 2D and 3D high-resolution black-blood techniques for carotid artery wall imaging in clinically significant atherosclerosisJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 4 2008Niranjan Balu PhD Abstract Purpose To compare two- (2D) and three-dimensional (3D) black-blood imaging methods for morphological measurements of the carotid artery wall and atherosclerotic plaque. Materials and Methods A total of 18 subjects with 50% to 79% carotid stenosis were scanned with 2D (2-mm slice thickness) and 3D (1-mm/0.5-mm actual/interpolated slice thickness) T1-weighted fast spin-echo (FSE) black-blood imaging sequences with double inversion-recovery (DIR) blood suppression. Morphological measurements (lumen area, wall area, vessel area, mean wall thickness, and maximal wall thickness), signal-to-noise ratio (SNR) in the wall and lumen, and wall-lumen contrast-to-noise ratio (CNR) were compared between 2D and 3D images. The effect of improved slice resolution in 3D imaging was evaluated for visualization of small plaque components. Results Lumen SNR (P = 0.16), wall SNR (P = 0.65), and CNR (P = 0.94) were comparable between 2D/3D. There was no difference in average lumen area (P = 0.16), average wall area (P = 0.99), average vessel area (P = 0.0.58), mean wall thickness (P = 0.09), and maximum wall thickness (P = 0.06) between 2D/3D. Distributions of small plaque components such as calcification were better characterized by the 3D acquisition. There was a higher sensitivity to motion artifacts with 3D imaging, resulting in three examinations with low image quality. Conclusion 2D and 3D protocols provided comparable morphometric measurements of the carotid artery. The major advantage of 3D imaging is improved small plaque component visualization, while the 2D technique provides higher reliability for image quality. J. Magn. Reson. Imaging 2008;27:918,924. © 2008 Wiley-Liss, Inc. [source] Using form analysis techniques to improve photogrammetric mass-estimation methodsMARINE MAMMAL SCIENCE, Issue 1 2008Kelly M. Proffitt Abstract Numerical characterization of animal body forms using elliptical Fourier decomposition may be a useful analytic technique in a variety of marine mammal investigations. Using data collected from the Weddell seal (Leptonychotes weddellii), we describe the method of body form characterization using elliptical Fourier analysis and demonstrated usefulness of the technique in photogrammetric mass-estimation modeling. We compared photogrammetric mass-estimation models developed from (1) standard morphometric measurement covariates, (2) elliptical Fourier coefficient covariates, and (3) a combination of morphometric and Fourier coefficient covariates and found that mass-estimation models employing a combination of morphometric measurements and Fourier coefficients outperformed models containing only one covariate type. Inclusion of Fourier coefficients in photogrammetric mass-estimation models employing standard morphometric measurements reduced the width of the prediction interval by 24.4%. Increased precision of photogrammetric mass-estimation models employing Fourier coefficients as model covariates may expand the range of ecological questions that can be addressed with estimated mass measurements. [source] Assessment of morphometric measurements of prostate carcinoma volumeCANCER, Issue 8 2002Andrew Renshaw M.D. No abstract is available for this article. [source] A FIELD-BASED METHOD FOR ESTIMATING AGE IN FREE-RANGING STELLER SEA LIONS (EUMETOPIAS JUBATUS) LESS THAN TWENTY-FOUR MONTHS OF AGEMARINE MAMMAL SCIENCE, Issue 2 2007James C. King Abstract Studies of health, survival, and development of juvenile Alaskan Steller sea lions (Eumetopias jubatus, SSL) require accurate estimates of age for wild-captured animals. However, the value and accuracy of several potential predictors of age have not been assessed with data from known-age free-ranging animals. During 2001,2005, forty-six individual SSL originally branded or tagged at ,6 mo of age were recaptured by the Alaska Department of Fish and Game (ADF&G). Using a series of general linear models, we evaluated the ability of morphometrics measurements: permanent canine tooth length (CTL), diastema (DIAS), whisker length (WHIS), and dorsal standard length (DSL) to predict the age of forty-six known-age juveniles (n= 46 ,23 mo of age). Permanent CTL was the strongest individual predictor (r2= 0.80); followed by DSL, DIAS, and WHIS (r2= 0.70, 0.56, and 0.45, respectively). The inclusion of a single sample from a 44-mo-old sea lion suggested quadratic relationships between age and all predictors for older animals. Only models including CTL predicted age to within 6 mo of known age. The equation Age = (,3.0112 +[0.6726 * CTL]+[0.4965 * DIAS]) allows for accurate age estimates of SSL ,23 mo for both sexes. [source] | |||||||||||||