Reentrant function

The Molecular Surface (MS) first introduced by Richards (19) was chosen as the 3D space where the MLP will be calculated. MS specifically refers to a molecular envelope accessible by a solvent molecule. Unlike the solvent accessible surface (20), which is defined by the center of a spherical probe as it is rolled over a molecule, the MS (19), or Connolly surface (21) is traced by the inwardfacing surface of the spherical probe (Fig. 2). The MS consists of three types of faces, namely contact, saddle, and concave reentrant, where the spherical probe touches molecule atoms at one, two, or three points, simultaneously. Calculation of molecular properties on the MS and integration of a function over the MS require a numerical representation of the MS as a manifold S(Mk, nk, dsk), where Mk, nk, dsk are, respectively, the coordinates, the normal vector, and the area of a small element of the MS. Among the published computational methods for a triangulated MS (22,23), the method proposed by Connolly (21,24) was used because it provides a numerical presentation of the MS as a collection of dot coordinates and outward normal vectors. In order to build the 3D-logP descriptor independent from the calculation parameters of the MS, the precision of the MS area computation was first estimated as a function of the point density and the probe radius parameters. When varying... 

Sidhu, J. S., Rajawat, Y. S., Rami, T. G., Gollob, M. H., Wang, Z., Yuan, R., Marian, A. J., DeMayo, F. J., Weilbacher, D., Taffet, G. E., Davies, J. K., Carling, D., Khoury, D. S., and Roberts, R. 2005. Transgenic mouse model of ventricular preexcitation and atrioventricular reentrant tachycardia induced by an AMP-activated protein kinase loss-of-function mutation responsible for Wolff-Parkinson-White syndrome. Circulation 111 21-29. 

Montgomery E. B. Dynamically Coupled, High-Frequency Reentrant, Non-linear Oscillators Embedded in Scale-Free Basal Ganglia-Thalamic-Cortical Networks Mediating Function and Deep Brain Stimulation Effects. Nonlinear Stud, 2004, 22, 385-421. 

Oscillations in the transition temperature of SF sandwiches as a function of F-layer thickness, <7f, including reentrant superconductivity [10, 11]. 

In a functional reentrant focus, the length of the circuit may vary depending on the conduction velocity and recovery characteristics of the impulse. The area in the middle of the loop is continually kept refractory by the inwardly moving impulse. The length of the circuit is not fixed but is the smallest circle possible such that the leading edge of the wavefront is continuously exciting tissue just as it recovers i.e., the head of the impulse nearly catches its tail. It differs from... 

Na Channel-Blocker Toxicity Conduction slowing in potential reentrant circuits can account for toxicity of drugs that block the Na+ channel (Table 34—1). For example, Na+ channel block decreases conduction velocity and hence slows atrial flutter rate. Normal AV nodal function permits... 

Figure 48. Semilogarithmic plot of the isothermal compressibility of N2 on boron nitride at 60.8 K as a function of the coverage in units of the complete /3 monolayer. The peak sequence starting at low coverages is attributed to the fluid to commensurate solid F-C and commensurate solid to reentrant fluid C-RF transitions and finally to second-layer growth RF-B (instead of a transition from the reentrant fluid to an incommensurate solid phase). (Adapted from Fig. 5 of Ref. 1.)...

The primary visual cortex contains six layers, numbered 1 through 6. Distinct functional and anatomic types of cells are found in each layer. Layer 4 contains neurons that receive information Ifom the LGN. Beyond the initial synapses, cells demonstrate progressively more complex responses. The outputs of VI project to an area known as visual area 2 (V2), which surrounds VI, and to higher visual areas in the occipital, temporal, and parietal lobes as well as to the superior colliculus. VI also sends reentrant projections back to the LGN. Reentrant projections are present at almost every level of the visual system [Edelman, 1978 FeUeman and Essen, 1991],... 

Edelman G.M. 1978. Group selection and phasic reentrant signalling a theory of higher brain function. In G.M. Edelman and V.B. Mountcastle (Eds.), The Mindful Brain, pp. 51-100, Cambridge, MIT... 

The elongation. A, was measured as a function of temperature for fixed load for various nematic phases as well as for a reentrant nematic phase in sidechain LCEs [6]. In the reentrant nematic phase the observed elongation A increased monotonical-ly (by up to 50%) as the temperature was decreased from the smectic A-reentrant nematic phase transition [6]. 

The heat flux at this condition is referred to as the critical heat flux, or CHF. It depends on the flow conditions, channel geometry, local quality, fluid properties, channel material, and flow history. Bergles and Kandlikar [8] discuss the CHF in microchannels from a systems perspective. It is important to establish CHF condition as a function of the mass flux and quality for a given system to ensure its safe operation. Qu and Mudawar [9] presented CHF data with water in 21 parallel minichannels of 215 x 821 pm cross-section over a range of G = 86—268 kg/(m s) and q" = 264-542 kW/m r = 0.0-0.56, and Fi = 121.3—139.8 kPa. Kosar et al. [5] present low-pressure water data in microchannels enhanced with reentrant cavities. Also, the correlation by Katto [10] developed for large channels may be applied for approximate CHF estimation in the absence of an established CHF correlation for microchannels. 

---