Infant's recognition of three‐dimensional form: Mirror image and structurally distinct objects

2021 ◽  
Author(s):  
Laura Hawkins ◽  
Tristin M. Nyman ◽  
Teresa Wilcox
Keyword(s):  
Three Dimensional ◽  
Mirror Image

Brief Organic Review

2016 ◽  
Author(s):  
Gary W. Morrow
Keyword(s):  
Functional Groups ◽  
Lewis Acids ◽  
Three Dimensional ◽  
Polarized Light ◽  
Mirror Image ◽  
Bond Line ◽  
Organic Chemical ◽  
Chemical Structures ◽  
Or Groups ◽  
Standard Formalism

In addition to simple hydrocarbon structures (alkanes, alkenes, alkynes, and aromatic systems) and alkyl groups (methyl, ethyl, propyl, isopropyl, etc.), this text assumes a familiarity with the most common functional groups associated with organic chemical structures and their basic reactivity patterns. Table 1.1 summarizes the names and structures of some of the more important functional groups we will be dealing with throughout the remainder of the book. It is important to remember that functional groups containing O or N with nonbonding electrons have an affinity for both protic and Lewis acids and are important participators in H-bonding. Groups containing a carbonyl (C=O) function are especially important, as these bonds are strongly polarized (δ+C=Oδ–), the C atom being electron deficient and the O atom electron excessive; this strong polarization is mainly responsible for the familiar reactivity patterns associated with carbonyl compounds. Figure 1.1 depicts the standard classification of isomers in organic chemical structures. Recall that constitutional isomers are compounds with the same molecular formula but different atom connectivity, such as 1-butanol versus 2-butanol. Stereoisomers, on the other hand, are compounds with the same formula and the same atom connectivity, differing from one another only in the three-dimensional orientation of their atoms in space. These are divided into two groups: enantiomers and diastereomers. Enantiomers are nonsuperimposable mirror image molecules whose asymmetry is usually the result of a tetrahedral carbon atom with four different atoms or groups attached to it, as in the 2-butanol enantiomers. Such chiral molecules rotate the plane of polarized light either (+) or (−) and so are said to be optically active. Achiral molecules, such as 1-butanol, do not rotate the plane of polarized light and so are optically inactive. A standard formalism for representation of a chiral center is to use bond line drawings with two of the four atoms or groups lying in the plane of the paper, a third projecting outward (wedge bond), and the fourth projecting inward (dashed bond).

scholarly journals An 1 H NMR determination of the three-dimensional structures of mirror-image forms of a Leu-5 variant of the trypsin inhibitor from Ecballium elaterium (EETI-II)

1994 ◽  
Vol 3 (2) ◽  
pp. 291-302 ◽  
Author(s):  
Katherine J. Nielsen ◽  
Dianne Alewood ◽  
John Andrews ◽  
Stephen B.H. Kent ◽  
David J. Craik
Keyword(s):  
Trypsin Inhibitor ◽  
Three Dimensional ◽  
Mirror Image ◽  
H Nmr

scholarly journals A novel 3D template for mandible and maxilla reconstruction: Rapid prototyping using stereolithography

2015 ◽  
Vol 48 (03) ◽  
pp. 263-273 ◽  
Author(s):  
Samir Kumta ◽  
Monica Kumta ◽  
Leena Jain ◽  
Shrirang Purohit ◽  
Rani Ummul
Keyword(s):  
Rapid Prototyping ◽  
Computer Aided Design ◽  
Treatment Plan ◽  
3D Structure ◽  
Three Dimensional ◽  
Bone Grafts ◽  
3D Models ◽  
Mirror Image ◽  
Anatomical Model ◽  
Patient Counselling

ABSTRACT Introduction: Replication of the exact three-dimensional (3D) structure of the maxilla and mandible is now a priority whilst attempting reconstruction of these bones to attain a complete functional and aesthetic rehabilitation. We hereby present the process of rapid prototyping using stereolithography to produce templates for modelling bone grafts and implants for maxilla/mandible reconstructions, its applications in tumour/trauma, and outcomes for primary and secondary reconstruction. Materials and Methods: Stereolithographic template-assisted reconstruction was used on 11 patients for the reconstruction of the mandible/maxilla primarily following tumour excision and secondarily for the realignment of post-traumatic malunited fractures or deformity corrections. Data obtained from the computed tomography (CT) scans with 1-mm resolution were converted into a computer-aided design (CAD) using the CT Digital Imaging and Communications in Medicine (DICOM) data. Once a CAD model was constructed, it was converted into a stereolithographic format and then processed by the rapid prototyping technology to produce the physical anatomical model using a resin. This resin model replicates the native mandible, which can be thus used off table as a guide for modelling the bone grafts. Discussion: This conversion of two-dimensional (2D) data from CT scan into 3D models is a very precise guide to shaping the bone grafts. Further, this CAD can reconstruct the defective half of the mandible using the mirror image principle, and the normal anatomical model can be created to aid secondary reconstructions. Conclusion: This novel approach allows a precise translation of the treatment plan directly to the surgical field. It is also an important teaching tool for implant moulding and fixation, and helps in patient counselling.

Autologous Fat Grafting With Combined Three-Dimensional and Mirror-Image Analyses for Progressive Hemifacial Atrophy

2016 ◽  
Vol 77 (3) ◽  
pp. 308-313 ◽  
Author(s):  
Xiaonan Yang ◽  
Rongwei Wu ◽  
Hui Bi ◽  
Haibin Lu ◽  
Zhenhua Jia ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Mirror Image ◽  
Fat Grafting ◽  
Autologous Fat Grafting ◽  
Hemifacial Atrophy ◽  
Autologous Fat ◽  
Progressive Hemifacial Atrophy ◽  
Image Analyses

Prefabricated Implants or Grafts with Reverse Models of Three-Dimensional Mirror-Image Templates for Reconstruction of Craniofacial Abnormalities

1999 ◽  
Vol 104 (5) ◽  
pp. 1413-1418 ◽  
Author(s):  
Sophia C. N. Chang ◽  
Yu-Fang Liao ◽  
Li-Man Hung ◽  
Ching-Shiow Tseng ◽  
Jung-Hsiang Hsu ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Mirror Image ◽  
Craniofacial Abnormalities ◽  
Image Templates

scholarly journals Space Deficits in Parkinson’s Disease Patients: Quantitative or Qualitative Differences from Normal Controls?

1993 ◽  
Vol 6 (4) ◽  
pp. 193-206 ◽  
Author(s):  
D. Natsopoulos ◽  
M.-S. Bostantzopoulou ◽  
Z. Katsarou ◽  
G. Grouios ◽  
G. Mentenopoulos
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Structural Model ◽  
Three Dimensional ◽  
Mirror Image ◽  
Homogeneous Population ◽  
Confirmatory Factor ◽  
Qualitative Nature ◽  
Almost All ◽  
Normal Controls

Twenty-seven patients with idiopathic Parkinson's disease (PD) and the same number of normal controls (NCs) were studied on a test battery including five conceptual categories of spatial ability. The two groups of subjects were matched for age, sex, years of education, socioeconomic status and non-verbal (Raven Standard Progressive Matrices) intelligence. A multivariate analysis of variance (MANOVA) showed that the PD patients performed less efficiently on almost all the tasks. A logistic regression analysis (LRA) classified 81.48% of the subjects into the PD group and 92.59% into NC group, indicating that left-right and back-front Euclidean orientation, three dimensional mental rotation and visuospatial immediate recognition memory of mirror image patterns discriminate well between the two groups. Application of a structural model (confirmatory factor analysis) demonstrated that both PD patients and the NC group stemmed from a homogeneous population, suggesting that the differences found between the two groups are of a quantitative rather than of a qualitative nature.

Origin of the homochirality of biomolecules

1995 ◽  
Vol 28 (4) ◽  
pp. 473-507 ◽  
Author(s):  
L. Keszthelyi
Keyword(s):  
Amino Acids ◽  
Three Dimensional ◽  
Polarized Light ◽  
Mirror Image ◽  
Reference Points ◽  
Dimensional Structure ◽  
Theoretical Treatment ◽  
Chiral Molecules ◽  
Amino Groups ◽  
The Right

Molecules built up from a given set of atoms may differ in their three-dimensional structure. They may have one or more asymmetric centres that serve as reference points for the steric distribution of the atoms. Carbon atoms, common to all biomolecules, are often such centres. For example, the Cα atom between the carboxyl and amino groups in amino acids is an asymmetric centre: looking ON ward (i.e. from the carbOxyl to the amiNo group, with the Cα oriented so that it is above the carboxyl and amino groups) the radical characterizing the amino acid may be to the right (D-molecules) or to the left (L-molecules). Nineteen of the 20 amino acids occurring in proteins have such a structure (the exception is glycine, where the radical is a hydrogen atom). These pairs of molecules cannot be brought into coincidence with their own mirror image, as is the situation with our hands. The phenomenon has therefore been named handedness, or chirality, from the Greek word cheir, meaning hand. The two forms of the chiral molecules are called enantiomers or antipodes. They differ in rotating the plane of the polarized light either to the right or to the left. The sense of rotation depends on the wavelength of the measuring light, but at a given wavelength it is always opposite for a pair of enantiomers. Chirality may also occur when achiral molecules form chiral substances during crystallization (for example, quartz forms D-quartz or Lquartz). A detailed theoretical treatment of molecular chirality is given by Barron (1991).

Three-dimensional imaging in craniofacial surgery: a review of the role of mirror image production

1990 ◽  
Vol 13 (5) ◽  
pp. 209-217 ◽  
Author(s):  
K. Fukuta ◽  
I. T. Jackson ◽  
C. N. McEwan ◽  
N. B. Meland
Keyword(s):  
Three Dimensional ◽  
Mirror Image ◽  
Craniofacial Surgery ◽  
Three Dimensional Imaging ◽  
Image Production

scholarly journals Mental Rotation in Human Infants

2008 ◽  
Vol 19 (11) ◽  
pp. 1063-1066 ◽  
Author(s):  
David S. Moore ◽  
Scott P. Johnson
Keyword(s):  
Mental Rotation ◽  
Sex Difference ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Familiar Object ◽  
Mirror Image ◽  
Human Infants ◽  
New Perspective ◽  
Three Dimensional Space

A sex difference on mental-rotation tasks has been demonstrated repeatedly, but not in children less than 4 years of age. To demonstrate mental rotation in human infants, we habituated 5-month-old infants to an object revolving through a 240° angle. In successive test trials, infants saw the habituation object or its mirror image revolving through a previously unseen 120° angle. Only the male infants appeared to recognize the familiar object from the new perspective, a feat requiring mental rotation. These data provide evidence for a sex difference in mental rotation of an object through three-dimensional space, consistently seen in adult populations.

scholarly journals The crystal structure of cholesteryl iodide

1945 ◽  
Vol 184 (996) ◽  
pp. 64-83 ◽  
Keyword(s):  
Crystal Structure ◽  
Electron Density ◽  
Heavy Atom ◽  
Three Dimensional ◽  
Mirror Image ◽  
Unit Cell ◽  
General View ◽  
General Arrangement ◽  
Carbon Carbon Bond ◽  
The Individual

The X-ray analysis of cholesteryl iodide is an example of the use that can be made of the presence of a heavy atom, here iodine, in working out the structure of an organic molecule containing a number of asymmetric centres. The method of analysis employed has been to calculate the electron density within the unit cell, using the observed F values and, at first, phase angles derived from the contributions of the iodine atoms alone. The electron density pattern so deduced necessarily has a centre of symmetry, since the positions of the two iodine atoms in the unit cell are related to one another by a centre of symmetry. It therefore shows, somewhat approximately, the positions of all the atoms in the molecule superimposed on those of a spurious mirror image molecule. Selection of the atomic positions belonging to one molecule was made through a consideration of normal carbon-carbon bond lengths and valency angles. The analysis was greatly assisted by the comparatively simple crystallographic character of the compound. Cholesteryl iodide crystallizes in two forms, A and B , of closely related crystal structure, both monoclinic, P 2 1 , with n = 2. Fourier projections on (010) were derived for both forms and show clearly the outlines of the sterol molecules and their general arrangement. The resolution of the atomic positions is best in the case of B and three-dimensional analysis was therefore attempted on this form only. The crystal structure derived confirms the general view of sterol crystallography put forward by Bernal and also the present accepted chemical structure of the sterol skeleton. The accuracy with which the positions of the individual atoms are fixed is not great, but it appears sufficient to establish their mode of linking and to provide new evidence on their stereochemical relations.

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