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Central defined

Kanner s seminal publication describing 11 autistic children used the word autistic to describe a remarkable lack of interest in other people and felt that this was a central defining feature of the syndrome (Kanner, 1943 Fein et al 1986 Volkmar et al., 1996). All autistic children fail to show the usual relatedness infants show to their parents and caretakers. They frequently lack the social smile as infants. Many do not recognize or discriminate most important people close to them, like parents and siblings. [Pg.34]

Usage of a federal approach in the IT Architecture process under strict consideration of central defined rules for integration and compatibility. Establishment of a company organization structure that is oriented at the V-Model for both the engineering departments and the IT-department. Only by doing so, continuous solutions can arise and can be operated. [Pg.570]

In order to determine the matrix thresholds, we present an expression of the coefficients dispersion that is related to the flattening of the cloud of the points around the central axis of inertia. The aim is to measure the distance to the G barycentre in block 3. So, we define this measure Square of Mean Distance to the center of Gravity as follow ... [Pg.235]

To operate the MPI or LPI equipment at stable and reprodncable inspection conditions modern units are equipped with a monitoring and control system called "Quality Assurance Package" (termed QAP). The QAP System is ba.sed on an industrial PC with a bus system and field sensors. It ensures that process parameters important for the reproducability of the MPI or LPI are controlled an held between defined limits by a central computer system. It can be adapted to any old system, as well as integrated into new systems. [Pg.628]

In the most connnonly employed mean-field models [25] of electronic structure theory, the configuration specified for study plays a central role in defining the mean-field potential. For example, the mean-field... [Pg.2163]

The concept of oxidation states is best applied only to germanium, tin and lead, for the chemistry of carbon and silicon is almost wholly defined in terms of covalency with the carbon and silicon atoms sharing all their four outer quantum level electrons. These are often tetrahedrally arranged around the central atom. There are compounds of carbon in which the valency appears to be less than... [Pg.162]

Complexes have already received some discussion it will be recalled that they are defined (and named) in terms of (a) the central... [Pg.362]

Fig. 2. Distance classes j = 0,1, 2,... (left) are defined for an atom (central dot) by a set of radii Rj+i the right cnrves sketch the temporal evolntion of the tot il force acting on the selected atom originating from cill atoms in distance class j shown are the exact forces (solid line), their exact valnes to be computed within the multiple time step scheme (filled squares), linear force extrapolations (dotted lines), and resulting force estimates (open sqnares). Fig. 2. Distance classes j = 0,1, 2,... (left) are defined for an atom (central dot) by a set of radii Rj+i the right cnrves sketch the temporal evolntion of the tot il force acting on the selected atom originating from cill atoms in distance class j shown are the exact forces (solid line), their exact valnes to be computed within the multiple time step scheme (filled squares), linear force extrapolations (dotted lines), and resulting force estimates (open sqnares).
The top part of Fig. 1 shows the time evolution of the central dihedral angle of butane, r (defined by the four carbon atoms), for trajectories... [Pg.228]

Fig. 1. The time evolution (top) and average cumulative difference (bottom) associated with the central dihedral angle of butane r (defined by the four carbon atoms), for trajectories differing initially in 10 , 10 , and 10 Angstoms of the Cartesian coordinates from a reference trajectory. The leap-frog/Verlet scheme at the timestep At = 1 fs is used in all cases, with an all-atom model comprised of bond-stretch, bond-angle, dihedral-angle, van der Waals, and electrostatic components, a.s specified by the AMBER force field within the INSIGHT/Discover program. Fig. 1. The time evolution (top) and average cumulative difference (bottom) associated with the central dihedral angle of butane r (defined by the four carbon atoms), for trajectories differing initially in 10 , 10 , and 10 Angstoms of the Cartesian coordinates from a reference trajectory. The leap-frog/Verlet scheme at the timestep At = 1 fs is used in all cases, with an all-atom model comprised of bond-stretch, bond-angle, dihedral-angle, van der Waals, and electrostatic components, a.s specified by the AMBER force field within the INSIGHT/Discover program.
To ensure that the arrangement of four atoms in a trigonal planar environment (e.g., a sp -hybridized carbon atom) remains essentially planar, a quadratic term like V(0) = (fe/2) is used to achieve the desired geometry. By calculating the angle 9 between a bond from the central atom and the plane defined by the central... [Pg.343]

However, one of the most successfiil approaches to systematically encoding substructures for NMR spectrum prediction was introduced quite some time ago by Bremser [9]. He used the so-called HOSE (Hierarchical Organization of Spherical Environments) code to describe structures. As mentioned above, the chemical shift value of a carbon atom is basically influenced by the chemical environment of the atom. The HOSE code describes the environment of an atom in several virtual spheres - see Figure 10.2-1. It uses spherical layers (or levels) around the atom to define the chemical environment. The first layer is defined by all the atoms that are one bond away from the central atom, the second layer includes the atoms within the two-bond distance, and so on. This idea can be described as an atom center fragment (ACF) concept, which has been addressed by several other authors in different approaches [19-21]. [Pg.519]

Various other ways to incorporate the out-of-plane bending contribution are possible. For e3plane bend involves a cakulation of the angle between a bond from the central atom and the plane defined by I he central atom and the other two atoms (Figure 4.10). A value of 0° corresponds to all four atoms being coplanar. A third approach is to calculate the height of the central atom above a plane defined by the other three atoms (Figure 4.10). With these two definitions the deviation of the out-of-plane coordinate (be it an angle or a distance) can be modelled Lt ing a harmonic potential of the form... [Pg.195]

One of the limitations of HF calculations is that they do not include electron correlation. This means that HF takes into account the average affect of electron repulsion, but not the explicit electron-electron interaction. Within HF theory the probability of finding an electron at some location around an atom is determined by the distance from the nucleus but not the distance to the other electrons as shown in Figure 3.1. This is not physically true, but it is the consequence of the central field approximation, which defines the HF method. [Pg.21]

Like MM2, MM-t includes coupling between bond stretching and angle bending. If the angle is defined to include atoms i, j, and k, where k is the central atom, then MM-t couples stretching of the ik and jk bonds with the angle ... [Pg.186]

HyperChem uses the improper dihedral angle formed by central atom - neighbor 1 - neighbor 2 - neighbor 3, where the order of neighbors is how they appear in a HIN file. Not all planar atoms customarily have associated improper torsions. The order of atoms is arbitrary but has been consistently chosen by the original authors of the CHARMM force field. The templates contain equivalent CHARMM definitions of improper torsions for amino acids. Improper dihedral angles cannot be defined that do not have a central atom, as is sometimes done in CHARMM calculations. [Pg.195]

If the mean or median provides an estimate of a penny s true mass, then the spread of the individual measurements must provide an estimate of the variability in the masses of individual pennies. Although spread is often defined relative to a specific measure of central tendency, its magnitude is independent of the central value. Changing all... [Pg.55]

A binomial distribution has well-defined measures of central tendency and spread. The true mean value, for example, is given as... [Pg.72]

The first step in the procedure is to define the purpose, objectives, and scope of the study. The more precisely this is done, the more focused and relevant the committee discussions can be. The next step is to collect all relevant information on the process under consideration. This includes flow diagrams, process equipment specifications, nominal flows, etc. The procedure is highly dependent on the reflabiUty of this information. Efforts expended here are worthwhile. Many committees use the flow sheet as the central stmcture to organize thek discussions. [Pg.471]

In addition to the weU-defined opioid systems in the central nervous system, the three opioid peptides and their precursor mRNA have also been identified in peripheral tissues. ( -Endorphin is most abundant in the pituitary, where it exists in corticotroph cells with ACTH in the anterior lobe and in melanotroph cells with MSH in the intermediate lobe (59). Enkephalin and pre-pro-enkephalin mRNA have been identified in the adrenal medulla (60) and this has been the source of material for many studies of pro-enkephalin synthesis and regulation. Pre-pro-enkephalin mRNA has also been identified in the anterior and posterior lobes of the pituitary (61). mRNA for all three opioid precursors has been identified in the reproductive system (62—64). POMC... [Pg.446]

Complex carbides are very numerous. Many newer compounds of this class have been discovered and their stmctures elucidated (20). The octahedron M C is typical where the metals arrange around a central carbon atom. The octahedra may be coimected via corners, edges, or faces. Trigonal prismatic polyhedra also occur. Defining T as transition metal and M as metal or main group nonmetal, the complex carbides can be classified as (/)... [Pg.455]

Equation (10-2) is true only for pipelines of relatively short lengths since otherwise the longitudinal resistance will be noticeable at longer distances. Thus in Eq. (10-2) / E will approach Z, not zero, for a long length. Here Z denotes the characteristic resistance defined in Eq. (24-66). Z is therefore the minimum grounding resistance for the case where current is fed at one end of the pipeline. This quantity is reduced by half for current fed in at a central point on the pipe. It follows from Eq. (24-66)... [Pg.266]

This potential ( )(r) is infinite if the central cell is not neutral, i.e., the sum of qi is not zero, and otherwise is an example of a conditionally convergent infinite series, as discussed above, so a careful treatment is necessary. The potential depends on the order of summation, that is, the order in which partial sums over n are computed. For example, for positive integers K, define ( )s (r) as... [Pg.106]


See other pages where Central defined is mentioned: [Pg.270]    [Pg.105]    [Pg.32]    [Pg.270]    [Pg.105]    [Pg.32]    [Pg.291]    [Pg.568]    [Pg.575]    [Pg.676]    [Pg.1211]    [Pg.1321]    [Pg.1596]    [Pg.2623]    [Pg.576]    [Pg.195]    [Pg.550]    [Pg.314]    [Pg.176]    [Pg.187]    [Pg.185]    [Pg.87]    [Pg.337]    [Pg.12]    [Pg.90]    [Pg.407]    [Pg.215]    [Pg.219]    [Pg.130]    [Pg.459]    [Pg.230]   
See also in sourсe #XX -- [ Pg.20 , Pg.31 ]




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