Tooth functions

Fig. 14.4 Left different examples of asymmetric periodic potential U(x) with the period P = 1. Only three periods are shown. From top to bottom U (x) is a saw-tooth function with smoothed angles (for details see [25] U(x) = —(0.25sin(2jrx/P) +...

Chapter 5 concerns the mechanical properties of tooth mineral, with particular emphasis on the use of nanoscale hardness measurements to elucidate the variations across the tooth surface and how they may be associated with tooth function. The influence of environmental factors, such as those described in Chapter 4, are also discussed. In addition, the authors present very recent studies, employing a variety of state-of-the-art techniques, on pellicle-coated enamel and on the early carious lesion, which complements the work described in Chapters 2 and 4, respectively. 

The acoustic excitation in the SEM/SFM hybrid system is performed with a 15 kV electron beam locally modulated by a saw tooth function with a frequency of 76.8 kHz. This leads to a behavior comparable to an acoustic line source with a directed emission [7]. The line source has a length of 43 pm and is located in parallel to the SFM cantilever, emitting acoustic waves vertically to the cantilever axis. 

Sharon, N. Lis, H. Lectins-proteins with a sweet tooth functions in cell recognition. Essays Biochem. 1995, 30 59-75 59-75. 

In all tests the macroscopic response a (i) to the applied signal (i) is rather simple. The monotonous branches of the saw-tooth function (f) are immediately responded by monotonous branches of <7(f). Thus little phase-shift is observed in these low-frequency load-cycling experiments. 

Amalgam restorations are prepared by mixing a powdered alloy with mercury to form a plastic moldable mass that is packed or condensed iato the prepared cavity. The cavity is designed to provide mechanical retention, maximum marginal mass, support to absorb the functional stresses transmitted through the restoration, and maximum protection to the remaining tooth stmcture. The restoration reestabUshes the normal tooth anatomical form and function. 

Figure 14-8 shows the effect of speed and load intensity on the flash temperature index. These curves are general in nature, since scoring is a function of pressure angle, lubrication, and tooth size. 

Peripheral neuropathy is degeneration of peripheral nerves. Because motor and sensory axons tun in the same nerves, usually both motor and sensory functions are affected in this disease. Neuropathies may be either acute (e.g., Charcot-Marie-Tooth disease) or chronic (e.g., Guillain-Barre syndrome) and are categorized as demyelinating or axonal. 

Purpose Generate data sets using mixed deterministic/stochastic models with N = 1. .. 1000. These data sets can be used to test programs or to do Monte Carlo studies. Five different models are predefined sine wave, saw tooth, base line, GC-peaks, and step functions. Data file SIMl.dat was... 

Various strains of oral streptococci produce D-glucosyltransferases which utilize sucrose as a o-glucosyl donor in the production of soluble and insoluble D-glucans. Consequently, it may be expected that some deoxyfluoro derivatives of sucrose function as competitive inhibitors for the dextransu-crases of tooth bacteria, thus preventing decay, or at least may be used as active-site probes for the enzymes. Another aim of these researches is to find non-metabolizable sweeteners. 

Mossbauer spectra are usually recorded in transmission geometry, whereby the sample, representing the absorber, contains the stable Mossbauer isotope, i.e., it is not radioactive. A scheme of a typical spectrometer setup is depicted in Fig. 3.1. The radioactive Mossbauer source is attached to the electro-mechanical velocity transducer, or Mossbauer drive, which is moved in a controlled manner for the modulation of the emitted y-radiation by the Doppler effect. The Mossbauer drive is powered by the electronic drive control unit according to a reference voltage (Fr), provided by the digital function generator. Most Mossbauer spectrometers are operated in constant-acceleration mode, in which the drive velocity is linearly swept up and down, either in a saw-tooth or in a triangular mode. In either case. 

Other investigators have also found that parameters of neurobehavioral function are associated with tooth lead levels. A cross-sectional cohort of school children in first grade was ascertained in the city of Aarhus, Denmark (Hansen et al. 1989), where the population is very homogeneous with regard to ethnicity and language. A total of 2,412 children were contacted and asked to contribute a shed deciduous tooth. A total of 1,291 children responded (response rate = 54%). Lead was determined in the... 

Other diseases with disruptions in neurofilament organization include diabetic neuropathy and Charcot-Marie-Tooth disease. For these diseases, the disruption of neuro filaments may be a secondary effect as in the case of trembler axons or a direct effect. For example, some forms of Charcot-Marie-Tooth peripheral neuropathy result from mutations in a neurofilament subunit [22, 43]. In most cases, neuronal degeneration is an eventual consequence, but neuronal function may be impaired prior to substantial loss of neurons. Generally, disruptions of neurofilaments have the most severe consequences in large motor neurons, which is consistent with the fact that the largest neurons have the highest levels of neurofilament expression. 

The vitamin A needs of the body are by no means centered in any one organ or tissue. It is necessary for vision, for tooth and bone development, for maintenance of healthy epithelial tissue in the skin and in many organs, for reproduction, etc. It is to be expected that deficiency would be exhibited in many ways and that in different individuals the symptoms would not be the same. The benefits of vitamin A administration may thus appear very different in different individuals, and this helps to explain why many kinds of benefits (part of which are probably real) have been ascribed (by physicians as well as others) to vitamin A administration. A substance with such diverse functions is bound to show different effects in different individuals, and, of course, for some individuals who have low requirements and get plenty in their food, its administration will appear to be wholly without effect. Otto Bessey, in discussing the problem of nutrition, has used vitamin A as an illustration of how widely different levels are needed to maintain different functions in experi-... 

Cuy [3], for example, observed that certain physical properties, such as melting points, boiling points, molecular volumes, densities and viscosities, are an alternating function of the number of carbon atoms in any homologous series, in such a manner that if melting points, for instance, are plotted against the number of carbon atoms the curve has a saw-tooth appearance (see Fig. 2.1). 

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