Search results for " morphometric analysis"
showing 7 items of 7 documents
Computer assisted morphometric analysis of ram sperm heads: Evaluation of different fixative techniques
1998
The recent development of automated systems for morphometric sperm head analysis has provided a series of objective parameters which have facilitated the standardization of morphological semen evaluation. This current work attempts to establish the optimum fixing conditions for the morphometric characterization of ram spermatozoa. Ejaculates were obtained from 5 Merino rams used for periodic collection of semen and were diluted at 1:50 with TEST medium. Air-dried smears were fixed either in ethanol-ether (1:1), 50% methanol, 2% glutaraldehyde or SUZA fixative, in which case the smear was pretreated with chloramine. The samples were then stained with commercial kit Hemacolor. Once the prepar…
Differentiation of Trichuris species eggs from non-human primates by geometric morphometric analysis
2020
Human trichuriasis is a neglected tropical disease which affects millions of people worldwide, mostly living in low socio-economic conditions. Numerous studies have been conducted over the past 10 years to compare the different techniques for T. trichiura eggs detection. Our study provides the first geometric morphometric analysis for the specific detection of eggs of Trichuris sp. isolated from stools of macaque (M. sylvanus), colobus (C. g. kikuyensis), grivets (C. aethiops) and the Brazza's monkey (C. neglectus) from zoos in Spain. Principal Component Analysis (PCA) arises as an efficient method to determine Trichuris spp. eggs. The selected measurements to be included in the PCA were pr…
GIS-MORPHOMETRIC ANALYSIS OF BADLANDS IN SICILY (ITALY)
2012
Sicily is affected by severe erosion processes, locally causing large volumes of soil loss and high denudation rates. The effects of intense water erosion phenomena are testified by the occurrence of badlands that constitute a common landscape particularly in the central and southern areas of the Island, where slopes are frequently underlain by clay-rich deposits. This paper presents the first results of an investigation carried out in a badlands site located in the head sector of the Imera Meridionale river basin, where geometry of several erosion channels has been characterized. Since length of linear erosion landforms such as rills, ephemeral gullies and permanent gullies, has been prove…
Molecular and biometric data on Carabus (Macrothorax) morbillosus Fabricius, 1792 (Coleoptera, Carabidae) from Mid Mediterranean areas
2022
The present study was carried out using molecular and biometric data of Carabus (Macrothorax) morbillosus from mid-Mediterranean areas to determine additional information on basal relationships among its representative subspecies. To this aim, two different kinds of approach were employed, including a morphometric analysis of four morphological parameters (i.e., elytra length, elytra width, pronotum length, pronotum width) of 128 specimens, and a Bayesian genetic analysis of 44 cytochrome oxidase subunit I (COI) partial sequences (i.e., 38 examined for the first time and six retrieved from GenBank database). Representative populations of C. (M.) morbillosus were sampled in four countries, n…
Long-term earthquake potential of active faults by using coastal and off-shore geological and morphological indicators
2017
Seismogenic fault models and active deformation ones coupled with models of both earthquake rate and earthquake probability were recently used in a time-independent modelling. The integration of models allows to estimates the magnitude, location, and likelihood of potentially damaging earthquake ruptures in regions with high natural seismic hazard. Improvements of these models imply the recognition of the spatial geometry of the larger, active faults, deemed to be the source of the most damaging future earthquakes. However, identifying active faults and calculating their geologic slip rates for deriving earthquake rates are not easy tasks in regions inaccessible to direct field studies like…
Morphometric and hydraulic geometry assessment of a gully in SW Spain
2016
Abstract Gully erosion represents one of the most significant types of land degradation in the Mediterranean areas, giving place to important on- and off-site effects. In this paper, a second-order gully located in SW Spain is analyzed. Along the gully, 28 cross-sections were established and measured with a Leica TCRM1102 laser total station, approximately every 6 months from 2001 to 2007. The sections were located at variable distance, placing them in areas where active erosion was evident. In total, 13 field measurements were carried out, and the geometric characteristics of 28 cross-sections were obtained. Morphometric analyses were carried out in both the main gully and a tributary reac…
Assessing, measuring and modelling erosion in calanchi areas: A review
2016
Calanchi are erosion landforms characterised by a heavily dissected terrain with steep, unvegetated slopes and channels with a dendritic pattern, which rapidly incise and extend headwards. Recent literature focusing on badland systems highlights their similarity with other larger fluvial landforms, stating that these behave as a full size laboratory, due to their rapid development in space and time and to the diversity of geomorphic processes involved. In this paper, a brief review of the most important results on badland research is firstly presented. Then, the morphometric similarity between calanchi and other erosion landforms is discussed. Finally, models quantitatively relating the vol…