Sexing sooty terns on Ascension Island from morphometric measurements

Sooty terns Onychoprion fuscata are one of the most abundant seabirds but breeding populations in many colonies have diminished. Rapid sexing of sooty terns in the field could be crucial in advancing our understanding of their reproductive biology, and in promoting conservation. However, sooty tern males and females are identical in their plumage and, thus, difficult to sex in the field. Morphometric measurements were taken from 63 adult sooty terns breeding on Ascension Island in 2005. A small blood sample was taken from the brachial vein to determine the bird's sex using standard PCR-based molecular techniques. Males were consistently larger in all morphometric measurements than females but considerable overlap between the sexes resulted in no single measurement being a useful discriminator of sex. A principal components analysis on a correlation matrix of seven morphometric measurements indicated that the first principal component (PC1) was a good 'body size' axis explaining 40.5% of the variance in the original matrix. The suite of head measurements all had high character loadings on PC1 and were, therefore, good indicators of the body size of sooty terns. Tarsus length and wing length were less reliable predictors of sex. Discriminant analyses revealed that a disciminant function incorporating head measurements and wing length allowed 77.8% of sooty terns to be sexed correctly based upon morphometric measurements alone. Further morphometric approaches to sexing should be explored with sooty terns captured in subsequent years.     

Predicting biomass of Atlantic salmon from morphometric lateral measurements

Previously biomass predictions have been derived from simple weight—length relationships. This study measured a variety of truss and conventional dimensions covering the lateral body profile of Atlantic salmon Salmo salar and, using regression analysis, developed a series of multifactor weight—lateral dimension relationships. Single-factor regression equations proved inadequate for predicting weight with percentage errors between real and estimated values ranging from −1.2±6.8% to 72.5 ± 225.6%. Fifty-two multifactor regression equations were generated that predicted accurately the weight of individual fish to within ±2% using combinations of conventional and truss measurements. Regression coefficients were found to be significantly different ( P <0.05) between Scottish and Norwegian strains, indicating morphological differences between the genetic groups. Norwegian fish were generally heavier for a given length compared to Scottish strains. This suggests that morphologically different strains of S. salar would require individual weight: lateral dimension relationships to be developed in order to predict biomass accurately to within commercially acceptable levels.     

Statistical methods for the practical clinical application of morphometric measurements

Four statistical methods are presented to determine the practical clinical value of measurements made from malignant tumors and to translate these measurements into a prediction of survival for each patient: the Cox statistical model, which must be derived from a data base of cases with known outcome; the null-rank test, a modified rank-sum test that provides an overall measure of the effectiveness of the Cox model; the predicted survival curve, an estimate of survival derived for each new patient from measurements of the primary tumor; and the standard error of measurement, an empirical method for estimating the variability introduced into predicted survival by errors in measurement. The value of these statistical methods was demonstrated by application to 200 cases of human intraocular melanoma, with the two predictive morphometric measurements used being the standard deviation of nucleolar area (SDNA) and the largest tumor dimension (LTD) derived from a single histologic slide of each tumor. Sufficient references and mathematical details are provided to allow anyone with moderate skills as a computer programmer to construct or obtain all of the relevant algorithms.     

Reproducibility of morphometric measurements of amyloid after various staining methods

Four histologic staining methods used for detecting amyloid (Congo red, viewed in both normal and polarized light, Sirius red, Crystal violet and Thioflavine T) were applied to heart muscle autopsy samples from 19 patients who suffered from amyloidosis. The amount of amyloid present was evaluated with morphometry (point counting) by five pathologists, and the interobserver reproducibility and variation of point counting in these staining methods were analyzed. The Sirius red method showed the least variation and was the most suitable stain for demonstrating amyloid with respect to reproducibility. Thioflavine T showed the greatest variation and was the least suitable stain with respect to reproducibility. The range of variation was considerable in all staining methods. The results show that stains differ in their specificity and sensitivity in staining amyloid, observers differ in their interpretation of staining results and certain stains result in more uniform interpretations than do others.     

Correlative morphometric and electrochemical measurements of serotonin content in earthworm muscles

Distribution of serotonin (5-HT) content of nervous fibers in both the somatic and the visceral muscle of Eisenia fetida have been investigated using immunocytochemical staining and voltammetric measurements. The somatic muscles in the body wall are richer innervated with serotoninergic fibers than the visceral ones in the pharynx and gizzard. The relative density of immunopositive fibers in the circular muscle layer of the body wall was found to be 2.73% while in the prostomium it was 1.02%. In the case of the muscle in pharynx 1.12% and in gizzard 1.28% density values were found. Differential Pulse Voltammetric (DPV) measurements with carbon fiber electrodes in the above mentioned muscle layers gave 272.5 nA, 135.0 nA, 122.5 nA, 137.5 nA peak heights, respectively. In the statistical analysis T-test was used at a confidence level of 95% (p<0.05). DPV current peak (i(p)) values reflect clearly the 5-HT concentration differences. Significant correlation was found between the innervation density and the i(p) values recorded in different areas. The i(p) values recorded at different times in different locations are determined by instantaneous serotonin concentration of the living tissue. As far as we know this is the first report using in vivo voltammetry investigating serotonin content in earthworm, E. fetida.     

Percutaneous transtracheal ventilation and morphometric measurements of cervical structures in swine

Fifteen swine cadavers were examined to determine a quick, reliable means of locating the level of the cricothyroid ligament from consistently palpable structures in the head and neck area. From calculations of measurements made on these cadavers, it was discovered that when a 21-43 kg pig was placed in a standard position, the measured length (L) from the angle of the mandible to the manubrium sterni multiplied by a factor of 0.48 equals the parameter Z [L (0.48) = Z]. Z was measured, beginning at the manubrium sterni, along the ventral midline. The endpoint of Z was at the level of the cricothyroid ligament. A catheter inserted at this point through the ligament into the airway provides a means of transtracheal ventilation. This method of ventilation can be used in emergencies to avoid a tracheostomy or as an alternative to endotracheal ventilation. This method was applied successfully to four anesthetized pigs as determined by a series of arterial blood gas samples.     

Nuclear morphometric measurements in rectal adenocarcinoma cells of patients of different races

The reasons for the different long-term prognoses of black and white patients following curative resection of a rectal adenocarcinoma are unknown. In order to investigate whether rectal adenocarcinomas in blacks have clinical or pathologic characteristics that are different from rectal adenocarcinomas in whites, 149 patients with potentially curable rectal cancers resected at the University of Chicago Medical Center between 1965 and 1981 were retrospectively analyzed. Clinical records, pathology reports and pertinent slides were reviewed in each case. In 142 cases, enough histologic material was available to perform nuclear photometric measurements and determinations of DNA content by the slide-cytophotometric method. There was no difference between black and white patients in the stage, differentiation degree, morphology and ploidy of the tumors, or in the presence of microinvasion, metastases and mucin production. However, adenocarcinoma cells of black patients had smaller nuclei than did the corresponding nuclei of white patients (54.7 +/- 2.34 sq microns versus 58.9 +/- 1.84 sq microns; P less than .05), and the neoplastic nuclei of black patients were significantly rounder and more regular than the nuclei of white patients (mean roundness factors of 1.1 +/- 0.003 vs. 1.11 +/- 0.005; P less than .05). Although these findings will require confirmation from other large clinical series, they suggest that the different prognoses of black and white patients after curative resection of a rectal adenocarcinoma may be explained by a different tumor behavior intrinsically related to different karyotypic characteristics of the neoplastic cells.     

Objective and automated protocols for the evaluation of biomedical search engines using No Title Evaluation protocols

Background  

The evaluation of information retrieval techniques has traditionally relied on human judges to determine which documents are relevant to a query and which are not. This protocol is used in the Text Retrieval Evaluation Conference (TREC), organized annually for the past 15 years, to support the unbiased evaluation of novel information retrieval approaches. The TREC Genomics Track has recently been introduced to measure the performance of information retrieval for biomedical applications.     

Phylogeography of the Calonectris shearwaters using molecular and morphometric data

We investigated phylogenetic relationships and the biogeographic history of the Calonectris species complex, using both molecular and biometric data from one population of the Cape Verde shearwater Calonectris edwardsii (Cape Verde Islands), one from the streaked shearwater C. leucomelas (western Pacific Ocean) and 26 from Cory's shearwater populations distributed across the Atlantic (C. d. borealis) and the Mediterranean (C. d. diomedea). The streaked shearwater appeared as the most basal and distant clades, whereas the genetic divergences among the three main clades within the Palearctic were similar. Clock calibrations match the first speciation event within Calonectris to the Panama Isthmus formation, suggesting a vicariant scenario for the divergence of the Pacific and the Palearctic clades. The separation between the Atlantic and Mediterranean clades would have occurred in allopatry by range contraction followed by local adaptation during the major biogeographic events of the Pleistocene. The endemic form from Cape Verde probably evolved as a result of ecological divergence from the Mediterranean subspecies. Finally, one Mediterranean population (Almeria) was unexpectedly grouped into the Atlantic subspecies clade, both by genetic and by morphometric analyses, pointing out the Almeria-Oran oceanographic front (AOOF) as the actual divide between the two Cory's shearwater subspecies. Our results highlight the importance of oceanographic boundaries as potentially effective barriers shaping population and species phylogeographical structure in pelagic seabirds.     

Behavioural and morphometric measurements of parental investment in southern elephant seals at the Falkland Islands

Parental investment is a key variable in the study of breeding strategies and life-histories evolution. In Pinnipedia, parental investment is usually calculated from direct measurements of pup weight gain or energy transfer between the mother and the pup. These direct methods always involve handling and restraining procedures that pose practical, logistical and ethical problems. To evaluate if weighing can be substituted by indirect observational estimates of parental investment, we analysed the relationship among various behavioural measures of suckling and post-natal growth in the southern elephant seal population of Sea Lion Island (Falkland Islands). Behavioural measures were in all cases a poor predictor of true investment as estimated by weighing. We concluded that there are currently no effective alternatives to direct handling, and that the best way to reduce the potential adverse impact of investment studies is the improvement of the handling protocol, which should include an estimation of the long-term effects on the health of handled animals. Further research is needed to test the validity of non-behavioural indirect methods (e.g. 3D photogrammetry).     

A Technic for Demonstrating Plasmodesma

Sections of potato tuber and epidermis from veins on the dorsal side of the sunflower leaf have proved most satisfactory in demonstrating plasmodesma. Kill fresh sections 5 minutes in a solution of 0.75 g. KI, 0.50 g. iodine in 100 cc. H₂O. Swell 5 minutes in 10% H₂SO₄. Mordant 5 minutes in a solution of 1.25 g. KI, 1.00 g. iodine in 100 cc. of 5% H₂SO₄. Wash in 5% H₂SO₄ until iodine starts to fade. Stain in a mixture of 0.5% gentian violet solution in 5% H₂SO₄ made up to a deep green color. Wash in a solution of 30 cc. glycerin, 2 g. ZnCl₂, 0.2 g. iodine, and a bit of KI in 60 cc. of water. Brush with a camel's hair brush, wash and mount in the same solution.     

Biological trace-element measurements using synchrotron radiation

The feasibility of performing X-ray fluorescence trace-element determinations at concentrations substantially below the ppm level for biological materials is demonstrated. Conditions for achieving optimum sensitivity were ascertained. Results achieved for five standard reference materials were, in most cases, in excellent agreement with listed values. Minimum detectable limits of 20 ppb were measured for most elements.     

Detection protocols for biotinylated probes: optimization using multistep techniques.

Recent studies using biotinylated in situ hybridization (ISH) have utilized a wide range of detection protocols for the biotinylated hybrids, leading to conflicting reports in the literature regarding sensitivity. In this study we compared 11 different detection protocols for biotinylated ISH using a measles virus-specific RNA probe on formalin-fixed, paraffin-embedded central nervous system tissue infected with measles virus. Maximum sensitivity was achieved with five-step detection protocols incorporating the use of a monoclonal antibody to biotin. Single-step detection protocols were found to be insensitive, as shown by their failure to detect viral nucleic acid in infected white-matter cells. Only by increasing the number of steps in the detection protocols were these infected cells demonstrable. Unless pre-hybridization, hybridization, and detection protocols are optimized, the results obtained in pathogenicity studies using ISH could be misinterpreted, leading to false conclusions about nucleic acid distribution. This also applies to the ever-increasing use of ISH for diagnostic purposes.     

Classification of genetic diversity in Abelmoschus tuberculatus germplasm collection using morphometric data

Abelmoschus tuberculatus Pal & Singh is endemic to India and is the close relative of cultivated okra, A. esculentus. Data on 49 selected accessions of A. tuberculatus were used to study genetic diversity for a range of morphological characters through the use of multi-variate statistics. Epicalyx segments, shape, size and persistence; petal colour and petal blotch; stem and fruit pubescence; pigmentation of various plant parts; days to flowering; plant height; and the fruit yield/plant were the important components of variation and contributed significantly to the total variation in germplasm accessions under study. The accessions could be grouped into four distinct clusters. The grouping pattern, however, did not reflect relationship between geographic origin and genetic diversity. The potential use of the variability in okra improvement programmes is discussed.     

A computer program using a nested analysis of variance in morphometric sampling

The quality of the sample set is absolutely essential in a morphometric analysis. In this paper a computer program is described which uses a nested analysis of variance in defining the sample. The program denotes those levels of the sampling protocol at which additional sampling should be performed to reduce the variance within the sample set. Furthermore, the program is written for use on a microcomputer which allows it to be used routinely in monitoring a sample set.     

Body condition score,morphometric measurements and estimation of body weight in mature Icelandic horses in Denmark

Background

Obesity is related to the development of several diseases like insulin resistance and laminitis in horses. The prevalence of obesity among mature Icelandic horses in Denmark has not been investigated previously. This study aimed to find the prevalence of obesity, to compare body condition score (BCS) based on owner perception with that of an experienced person and to correlate the BCS to body weight (BW) and morphometric measures in a group of mature Icelandic horses in Denmark. A total of 254 Icelandic horses (≥4 years; 140 geldings, 105 mares, 9 stallions) from 46 different farms were included. All horses were assigned a BCS on a scale from 1 to 9 (1 is poor, 5 is moderate and 9 is extremely fat) by their owner and by an experienced person. Two weight tapes were used to assess BW. Girth circumference (GC), neck circumference (NC) and height at withers (HW) were measured, and the GC:HW and NC:HW ratios were calculated.

Results

Categorising the horses into four groups, 5.9 % were underweight (BCS 3–4), 70.1 % were optimal (BCS 5–6), 13.8 % were overweight (BCS 7) and 10.2 % were obese (BCS 8–9). The GC:HW and NC:HW ratios increased with increasing BCS, as did the BW estimated with the weight tapes. A GC:HW ratio >1.21 might indicate overweight or obesity in Icelandic horses. Horse owners underestimated the BCS of their horses compared to an experienced person.

Conclusions

The results from this study show that 24.0 % of mature Icelandic horses in Denmark are overweight or obese, and that owners tend to underestimate the BCS of their Icelandic horses. The GC:HW ratio might indicate overweight or obesity, however, the ratio for Icelandic horses is different than reported for horses and ponies of other breeds.

     

Aggregation of Escherichia coli B/r A during agar filtration: effect on morphometric measurements.

We have investigated the phenomenon of particle aggregation in a sample of 71,038 Escherichia coli B/r A cells in balanced exponential growth, during preparation for electron microscopy by agar filtration. The bacteria were photographed in a transmission electron microscope and the dimensions and spatial relationships among all the members of each aggregate were recorded using an interactive image processing system. The proportion of aggregated cells, 22%, is much greater than that found by direct count in a light microscope (7%), implying that most aggregation takes place during the preparation stages. The aggregated cells are about 1% narrower than the free cells, because of mutual compression, and 1.5% longer, because of a selection bias in favor of longer cells. From a statistical analysis of the data, we conclude that the clustering of cells into aggregates in the course of sample preparation is the result of random encounters during the settling on the collodion membrane and of the changing surface tension during the drying process. A method is proposed to correct morphometric measurements for the distortion caused by cellular aggregation of this kind.