A study on the inheritance of the transverse cephalic curvature index

The transverse cephalic curvature index defined by Dash Sharma (Proc. Indian Sci. Cong. 54:496, 1967) was studied in 38 families of both the Adivasi population of Orissa and the Andhras of Visakhapatnam (Andhra Pradesh). Correlation coefficients estimated for the different familial combinations gave a negative result, suggesting the non-hereditary nature of the index.     

Inheritance of the cephalic index

Using data from 462 paternity examinations, it was found that, (1) The cephalic index of an infant does not correlate at all closely to those of his or her parents as a pair, nor with that of the like sexed parent, but (2) The cephalic index of an infant, in a majority of cases, falls within a single percentage point of one of the two parents. Because of this it is hypothesized that this aspect of skullshape in inherited in a unitary fashion.     

Family studies on transverse fronto-parietal index

In the present paper an attempt has been made to study the Transverse Fronto-parietal Index on 200 biological families with 577 children, taking the age and the sex of the individuals into consideration. The present study on 200 Punjabi families hints at the dominating nature of the mesometopic type (70.4–74.9) as evidenced from the index value.     

Model analogues in the study of cephalic circulation

Simple laboratory models are useful to demonstrate cardiovascular principles involving the effects of gravity on the distribution of blood flow to the heads of animals, especially tall ones like the giraffe. They show that negative pressures cannot occur in collapsible vessels of the head, unless they are protected from collapse by external structures such as the cranium and cervical vertebrae. Negative pressures in the cerebral-spinal fluid (CSF) can prevent cerebral circulation from collapsing, and the spinal veins of the venous plexus can return blood to the heart in essentially rigid vessels. However, cephalic vessels outside the cranium are collapsible, so require positive blood pressures to establish flow; CSF pressure and venous plexus flow are irrelevant in this regard. Pressures in collapsible vessels reflect pressures exerted by surrounding tissues, which may explain the observed pressure gradient in the giraffe jugular vein. Tissue pressure is distinct from interstitial fluid pressure which has little influence on pressure gradients across the walls of major vessels.     

Effects of unsaturation and curvature on the transverse distribution of intramolecular dynamics of dipyrenyl lipids.

The roles of acyl chain unsaturation and curvature in the excimer formation efficiency (EFE) of site-specific conjugated pyrene molecules in lipid membranes have been investigated by steady-state and time-resolved fluorescence spectroscopy. Six 1-2-(pyrenyl-n-acyl)-phosphatidylcholine (dipy(n)PC) probes, with pyrenyl chains of varying methylene units n from 4 to 14 carbons, were incorporated separately into dioleoylphosphatidylcholine (DOPC) or dioleoylphosphatidylethanolamine (DOPE) lipid membranes at 0.1 mol%. Both the excimer-to-monomer fluorescence intensity ratio and association-to-dissociation rate constant ratio of conjugated pyrenes were used to quantify EFE. At all temperatures (T = 0-30 degrees C) and for n = 4 and 6, the EFE for DOPE was always smaller than EFE for DOPC. At T < 10 degrees C (where DOPE and DOPC are in the liquid crystalline L alpha phase) and for n > 8, the EFE for curvature frustrated DOPE was significantly greater than EFE for nonfrustrated DOPC (control), and the difference increased gradually with n. At T> 18 degrees C (where DOPE is in the inverted hexagonal H(II) phase and DOPC is in the L alpha phase) and for n > 8, EFE for the curvature-relaxed DOPE was again smaller than the EFE for DOPC control. The contributions of splay conformation and internal dynamics of pyrenyl chains to EFE were examined separately using a lattice model. Our results suggest that i) the cis double bonds of the host lipid matrix strongly perturb both the conformation and dynamics of conjugated pyrenes at the specific location around n = 8, and ii) the lateral stress at the upper part (n < 8) of the curvature frustrated bilayer membranes (DOPE) may be significantly relaxed once the membrane surface adopts a favorable negative interfacial curvature.     

Secular change in body height and cephalic index of Croatian medical students (University of Rijeka)

An investigation of body height and cephalic measurements was performed among five groups of first-year medical students of the University of Rijeka School of Medicine (Rijeka, Croatia). Body height and different cephalic measurements showed normal distribution, both in male and female students. Differences between measured variables were statistically analyzed by ANOVA. No significant difference with regard to year of birth was found in either males or females. The cephalic index showed no statistically significant difference between sexes or with regard to body height, while head breadth and length correlated significantly with birth year and body height, both in males and females. Head breadth decreased within the study period, while head length increased. Results were compared with those of similar studies from the mid-20th century. Student's t-test showed a significant change of cephalic indices and other head measurements, but not of body height, in males. The frequency difference between various head shapes was tested using the chi-square test. A significant increase of dolichocephalic and mesocephalic and a significant decrease of brachycephalic head shape were found in both sexes. These results suggest a continuity of the debrachycephalization process observed in our population at the past midcentury.     

Performance of MAX test and degree of dominance index in predicting the mode of inheritance

We evaluate power performance to detect the correct mode of inheritance in gene-disease associations of two different approaches: the MAX test and the degree of dominance index or h-index. The MAX test is a special case of the conditional independence tests that simultaneously test for association and select the most likely genetic model based on a three-dimensional normal distribution. The h-index is based on the philosophy of using orthogonal contrasts to infer the mode of inheritance quantitatively. A population genetic model is developed where the real mode of inheritance is known a priori and power performance can be accurately determined. The simulations showed that none of the two approaches generally outperforms the other, nor each of them provides a panacea to estimate efficiently the mode of inheritance in all parameter space. However, the simultaneous application of both approaches can provide insights in determining the underlying mode of inheritance.     

A novel image-analysis technique for kinematic study of growth and curvature

Kinematic analysis has provided important insights into the biology of growth by revealing the distribution of expansion within growing organs. Modern methods of kinematic analysis have made use of new image-tracking algorithms and computer-assisted evaluation, but these methods have yet to be adapted for examination of growth in a variety of plant species or for analysis of graviresponse. Therefore, a new image-analysis program, KineRoot, was developed to study spatio-temporal patterns of growth and curvature of roots. Graphite particles sprinkled on the roots create random patterns that can be followed by image analysis. KineRoot tracks the displacement of patterns created by the graphite particles over space and time using three search algorithms. Following pattern tracking, the edges of the roots are identified automatically by an edge detection algorithm that provides root diameter and root midline. Local growth rate of the root is measured by projecting the tracked points on the midline. From the shape of the root midline, root curvature is calculated. By combining curvature measurement with root diameter, the differential growth ratio between the greater and lesser curvature edges of a bending root is calculated. KineRoot is capable of analyzing a large number of images to generate local root growth and root curvature data over several hours, permitting kinematic analysis of growth and gravitropic responses for a variety of root types.     

Classification of bronchial epithelial atypias by the atypia status index

The atypia status index (ASI) is a categorization method of classifying digitized images of atypical bronchial epithelial cells in sputum. The ASI is defined as a linear composite of features linearly related to atypia stage. Over 200 features were examined for more than 3,000 cells that had been classified by atypia stage (squamous metaplasia, mild, moderate or severe atypia and malignant) and staining characteristic (orangeophilia and nonorangeophilia). We reduced the number of features by using a selection process to minimize redundancy. The feature weights were optimized via a least-squares procedure. The 14 features selected accounted for over 60% of the variation of atypia stage and produced ASI values that were within one atypia stage of the criterion classification for over 90% of the cells. The results are consistent with the hypothesis of a progressive pattern in bronchial epithelial atypia and indicate the feasibility of using image analysis for mass screening of premalignant atypias in sputum from subjects considered to be at high risk for lung cancer.