scholarly journals CT examination of the head of the Baikal seal (Phoca sibirica)

1999 ◽  
Vol 194 (1) ◽  
pp. 119-126
Author(s):  
HIDEKI ENDO ◽  
HIROYUKI SASAKI ◽  
YOSHIHIRO HAYASHI ◽  
EVAGENY A. PETROV ◽  
MASAO AMANO ◽  
...  

We carried out a computerised tomographic (CT) examination to elucidate the modifications in the head related to orbital enlargement in the Baikal seal. Transverse CT images showed that (1) the external frontal contours and the frontal sinuses are compressed medially and ventrally by the orbital enlargement; (2) the caudal part of the nasal cavity and nasopharynx are compacted ventrally; and (3) the cranial cavity is displaced caudally. The neurocranium is obviously separated from the facial part in the transverse plane at the caudal region of the orbit. The disposition of the mandible, zygomatic arch, temporal bone, and the masseter, temporal, digastric and pterygoid muscles is changed by the enlarged orbit in the 3-dimensional reorganisation of the head in this species. It is suggested that adaptation for the Lake Baikal environment primarily resulted in orbital enlargement, and that the altered orbital design may subsequently have influenced the form and function of the masticatory and respiratory system.

2015 ◽  
Vol 9 (1) ◽  
pp. 263-266 ◽  
Author(s):  
Pegah Bronoosh ◽  
Leila Khojastepour

Background : As the basic biological relationship of form and function, changes in the normal pattern of nasopharyngeal space can profoundly affect the development of the craniofacial growth. The lateral cephalogram, part of the patient’s normal records for orthodontic treatment, may show some of these changes either at the initial examination or later during treatment. The validity of the information the lateral cephalogram may present, have been questioned previously. The aim of this study was to assess correlation between the area and the volume measurements of pharyngeal airway size in a lateral cephalogram and a 3-dimensional (3D) cone-beam computed tomography (CBCT) scan in adolescent subjects. Materials and Methods : CBCT scan and a lateral cephalogram of 35 subjects which were taken within 1 week were included in this study. Airway area of the region of interest from the lateral cephalogram and airway volume over the same of region of interest from the CBCT scan were assessed for all patients. The correlation between the area and the volume measurements were evaluated statistically by Pearson’s correlation coefficient test. Mann Whitney U Test was used for comparing the area and the volume measurements in different sex. Results : Strong correlation was found between lateral cephalogram and CBCT measurements of pharyngeal airway. (r=0.831). Conclusion : Pharyngeal airway area on a lateral cephalogram is correlated strongly with volumetric data on CBCT images. Henceforth the use of CBCT images for volume measurements in orthodontic patients can aid in the better evaluation of airways and acted as a diagnostic instrument in this area.


Author(s):  
Patricia G. Arscott ◽  
Gil Lee ◽  
Victor A. Bloomfield ◽  
D. Fennell Evans

STM is one of the most promising techniques available for visualizing the fine details of biomolecular structure. It has been used to map the surface topography of inorganic materials in atomic dimensions, and thus has the resolving power not only to determine the conformation of small molecules but to distinguish site-specific features within a molecule. That level of detail is of critical importance in understanding the relationship between form and function in biological systems. The size, shape, and accessibility of molecular structures can be determined much more accurately by STM than by electron microscopy since no staining, shadowing or labeling with heavy metals is required, and there is no exposure to damaging radiation by electrons. Crystallography and most other physical techniques do not give information about individual molecules.We have obtained striking images of DNA and RNA, using calf thymus DNA and two synthetic polynucleotides, poly(dG-me5dC)·poly(dG-me5dC) and poly(rA)·poly(rU).


2011 ◽  
Author(s):  
Scott Fluke ◽  
Russell J. Webster ◽  
Donald A. Saucier

2013 ◽  
Author(s):  
Joshua Wilt ◽  
William Revelle

Author(s):  
Barbara Schönig

Going along with the end of the “golden age” of the welfare state, the fordist paradigm of social housing has been considerably transformed. From the 1980s onwards, a new paradigm of social housing has been shaped in Germany in terms of provision, institutional organization and design. This transformation can be interpreted as a result of the interplay between the transformation of national welfare state and housing policies, the implementation of entrepreneurial urban policies and a shift in architectural and urban development models. Using an integrated approach to understand form and function of social housing, the paper characterizes the new paradigm established and nevertheless interprets it within the continuity of the specific German welfare resp. housing regime, the “German social housing market economy”.


1988 ◽  
Vol 6 (1) ◽  
pp. 27-59 ◽  
Author(s):  
Joseph P. Swain

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