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The disturbance due to a time-harmonic normal point load and thermal source in a homogeneous isotropic thermoelastic, half-space is investigated by applying the Hankel transform technique in the context of generalized theories of thermoelasticity. The inverse transform integrals are evaluated using Romberg integration with adaptive stepwise after using the results from successive refinements of the extended trapezoidal rule followed by extrapolation of the results to the limit when the step-size tends to zero. The displacement, temperature, and stresses so obtained in the physical domain are computed numerically and presented graphically in Figures 1-12 in different situations for Aluminium-epoxy composite material. A comparison of the results for different theories of generalized thermoelasticity is also presented.

The propagation of thermoelastic waves in homogeneous isotropic plate subjected to stress-free and rigid insulated and isothermal conditions is investigated in the context of conventional coupled thermoelasticity (CT), Lord-Shulman (LS), Green-Lindsay (GL), and Green-Nagdhi (GN) theories of thermoelasticity. Secular equations for the plate in closed form and isolated mathematical conditions for symmetric and skew-symmetric wave mode propagation in completely separate terms are derived. It is shown that the motion for SH modes gets decoupled from the rest of the motion and remains unaffected due to thermo-mechanical coupling and thermal relaxation effects. The phase velocities for SH modes have also been obtained. The results for coupled and uncoupled theories of thermoelasticity have been obtained as particular cases from the derived secular equations. At short wavelength limits the secular equations for symmetric and skew-symmetric waves in a stress-free insulated and isothermal plate reduce to Rayleigh surface waves frequency equations. Finally, the numerical solution is carried out for aluminum-epoxy composite material and the dispersion curves for symmetric and skew-symmetric wave modes are presented to illustrate and compare the theoretical results.

Keeping in view the increased usage of orthorhombic materials in the development of advanced engineering materials such as fibers and composites and other multilayered media, the aim of the present paper is to give a detailed account of the plane harmonic generalized thermoelastic waves in orthorhombic materials. According to the frequency equation, the four waves, a quasi-longitudinal, two quasi-transverse, and a quasi-thermal wave, can propagate in an orthorhombic crystal. When plane waves propagate along the axis of an orthorhombic solid, then only the longitudinal and thermal waves are coupled, whereas the transverse waves get decoupled from the rest of the motion. For plane waves propagating in one plane of the solid, only the SH wave in that plane remains purely transverse and gets decoupled from the rest of the motion and vice versa. The other three waves are coupled and get modified due to thermal variations and relaxation time. The particle paths and stability of the waves have been discussed and the results verified numerically. These have been represented graphically for single crystals of solid helium and cobalt material.

The paper concentrates on the study of reflection and transmission characteristics of waves at the interface of a thermoelastic-diffusive solid half-space underlying an inviscid liquid. The analytic expressions for amplitude ratios, reflection and transmission coefficients, in terms of incident angles and material parameters have been obtained for quasi-longitudinal (qP) and quasi-transverse (qSV) wave incidence. The normal and grazing incidence cases have also been derived and discussed. The total reflection phenomenon has also been discussed. The energy law has been shown to be obeyed by the incidence, reflected and transmitted waves by deriving energy equation and its simulation. The numerical computations of reflection and transmission coefficients have been carried out for copper material half-space in contact with water at the interface by using MATLAB software. The computer simulated results have been presented graphically in order to bring out clear comparison of various situations.

This article is aimed at investigating the plane strain problems in generalized theory of thermoelasticity in a homogeneous, transversely isotropic medium by employing an eigenvalue approach after applying the technique of Laplace and Fourier transforms. An example of a half-space having a step input of temperature has been presented in order to illustrate the application of the approach. The results for coupled thermoelasticity and in the case of homogeneous isotropic medium have also been deduced as particular cases. The results obtained can be used for a broad class of problems in generalized thermoelasticity. The integral transforms have been inverted numerically to obtain the displacement, temperature, and stress fields in the physical domain. The results for these quantities are given and illustrated graphically.

The state space approach to generalized thermoelasticity is reformulated, and it is established that the solutions to the generalized thermoelastic fields can be formed by an entirely different approach as was illustrated by Sosa and Bahar for coupled thermoelastic problems. The article is concemed with a one-dimensional description of a semi-infinite body subjected to two types of boundary conditions; namely: (i) a step input of temperature and zero stress and (ii) a step input of stress and zero temperature. The various results obtained are found to be discontinuous for certain values of time in both the Lord and Shulman and the Green and Lindsay theories of thermoelasticity, and most of the jumps are shown to decay exponentially with time. The results for conventional coupled theory of thermoelasticity are obtained as a particular case of the generalized theory.

In this article a two-dimensional axisymmetric problem in a homogeneous transversely isotropic medium has been studied by employing the eigenvalue approach after applying the technique of Laplace and Hankel transforms. An example of infinite space with concentrated force at the origin has been presented to illustrate the application of the approach. The results for coupled thermoelasticity and in the case of a homogeneous isotropic medium have also been deduced. The results obtained can be used for a broad class of problems in generalized thermoelasticity. The integral transforms have been inverted by using a, numerical technique to obtain the displacements, temperature, and stresses in the physical domain. The results for these quantities are given and illustrated graphically.

Additive layered rapid manufacturing offers the ability to create physical parts with little or no restriction from shape complexity. Modelling and validation of this new technology requires embedded sensors which challenges conventional sensor technology. In this work, fibre Bragg gratings [FBG] have been embedded inside components made from a polymer during the manufacturing process of layer-by-layer additive manufacturing technology by laser sintering of powder layers using a commercial EOS P730 system. The technique is based on the insertion of a fibre carrier component, replacing a removable ‘place holder’ during an interruption of the build process. Tensile test specimens have been subjected to extended cyclic tensile loading trials at low strain levels of up to 400 µ-strain. The test specimen show stable and reproducible response over a period in excess of 330 days and 142000 load cycles. Polyimide and acrylic jacketed fibres have been trialled and the effect of minor deformations of the component through internal stresses depending on the fibre jacket type is discussed.

The present investigation is concerned with the study of extensional and transversal wave motions in an infinite homogenous transversely isotropic, thermoelastic plate by using asymptotic method in the context of coupled thermoelasticity, Lord and Shulman (1967, “The Generalized Dynamical Theory of Thermoelasticity,” J. Mech. Phys. Solids, 15, pp. 299–309), and Green and Lindsay (1972, “Thermoelasticity,” J. Elast., 2, pp. 1–7) theories of generalized thermoelasticity. The governing equations for extensional, transversal, and flexural motions have been derived from the system of three-dimensional dynamical equations of linear thermoelasticity. The asymptotic operator plate model for extensional motion in a homogeneous transversely isotropic thermoelastic plate leads to sixth degree polynomial secular equation that governs frequency and phase velocity of various possible modes of wave propagation at all wavelengths. It is shown that the purely transverse motion (SH mode), which is not affected by thermal variations, gets decoupled from rest of the motion. The Rayleigh–Lamb frequency equation for the plate is expanded in power series in order to obtain polynomial frequency equation and velocity dispersion relations. Their validation has been established with that of asymptotic method. The special cases of short and long wavelength waves are also discussed. The expressions for group velocity of extensional and transversal modes have been derived. Finally, the numerical solution is carried out for homogeneous transversely isotropic plate of single crystal of zinc material. The dispersion curves of phase velocity and attenuation coefficient are presented graphically.

The exact free vibration analysis of stress free or rigidly fixed, thermally insulated/isothermal, transradially (spherically) isotropic thermoelastic solid sphere has been presented in context of nonclassical thermoelasticity. The transradially isotropic is also frequently referred as spherically isotropic in the literature. The basic governing equations of linear generalized thermoelastic, transradially isotropic, sphere have been uncoupled and simplified with the help of Helmholtz decomposition theorem. The formal solution of the coupled system of partial differential equations has been obtained by employing matrix Fröbenius method of extended series. The secular equations for the existence of possible modes of vibrations in the sphere have been derived by employing boundary conditions. The special cases of spheroidal (S-mode) and toroidal (T-mode) vibrations have also been deduced and discussed. It is found that the toroidal motion gets decoupled from the spheroidal one and remains independent of thermal variations and thermal relaxation time. In order to illustrate the analytical development, the numerical solution of secular equations for spheroidal motion (S-mode) is carried out with respect of magnesium and solid helium spheres. The lowest frequency and damping factor of vibrational modes have been computed with the help of MATLAB programming and the results are presented graphically. The study may find applications in aerospace, navigation, geophysics tribology, and other industries where spherical structures are in frequent use.

The out-of-plane vibrations of a generalized thermoelastic circular plate are studied under different environmental temperature, plate dimensions and boundary conditions. The analytical expressions for thermoelastic damping of vibration and phase velocity of circumferential surface wave modes are obtained. It is noticed that the damping of vibrations and phase velocities of circumferential surface wave modes significantly depend on thermal relaxation time in addition to thermoelastic coupling in circular plates under resonance conditions. The surface conditions also impose significant effects on the vibrations of such resonators. The expressions for displacement and temperature fields in the plate resonator are also derived and obtained. Some numerical results have also been presented for illustration purpose in case of silicon material plate.

In this paper the general axisymmetric and plane strain problems in generalized theories of thermoelasticity have been investigated by employing the eigenvalue approach after applying the Laplace and the Hankel transforms technique. Examples of an infinite space and a half space have been presented in order to illustrate the application of the approach. The results for the coupled thermoelasticity can be obtained as particular cases of the obtained results by setting thermal relaxation times equal to zero. The obtained results can be used for a broad class of problems in generalized thermoelasticity.

In the present paper, an exact three-dimensional vibration analysis of a transradially isotropic, thermoelastic solid sphere subjected to stress-free, thermally insulated, or isothermal boundary conditions has been carried out. Nondimensional basic governing equations of motion and heat conduction for the considered thermoelastic sphere are uncoupled and simplified by using Helmholtz decomposition theorem. By using a spherical wave solution, a system of governing partial differential equations is further reduced to a coupled system of three ordinary differential equations in radial coordinate in addition to uncoupled equation for toroidal motion. Matrix Fröbenious method of extended power series is used to investigate motion along radial coordinate from the coupled system of equations. Secular equations for the existence of various types of possible modes of vibrations in the sphere are derived in the compact form by employing boundary conditions. Special cases of spheroidal and toroidal modes of vibrations of a solid sphere have also been deduced and discussed. It is observed that the toroidal motion remains independent of thermal variations as expected and spheroidal modes are in general affected by thermal variations. Finally, the numerical solution of the secular equation for spheroidal motion (S-modes) is carried out to compute lowest frequency and dissipation factor of different modes with MATLAB programming for zinc and cobalt materials. Computer simulated results have been presented graphically. The analyses may find applications in aerospace, navigation, and other industries where spherical structures are in frequent use.

The distribution of deformation, temperature, and stress in a homogeneous isotropic, thermally conducting, infinitely extended, stretched elastic plate due to a flat nose cylindrical projectile has been studied in the context of the Green–Lindsay theory of thermoelasticity. As the ‘‘second sound’’ effects are short lived, the discussion is confined to small‐time approximations. The short‐time solutions have been obtained by using the Laplace transforms technique. The deformation is found to be continuous but the temperature and stress are found to be discontinuous. The jumps obtained have been computed numerically and are represented graphically for carbon‐steel material.

The distribution of displacement, temperature, and stress in a homogeneous, isotropic, thermally conducting, infinitely extended, stretched elastic plate resulting from a flat-nosed, cylindrical projectile have been investigated in the context of the Lord-Shulman theory of thermoelasticity. The Laplace transform technique is used to obtain the solutions. Because the second-sound effects are of short duration, the discussion is confined to small time approximations. The displacement is found to be continuous, but temperature and stress are found to be discontinuous. The long time solutions are also discussed. The jumps have been computed numerically and are represented graphically for carbon-steel material.

The present paper deals with the investigations of the distribution of deformation, temperature, stresses and magnetic field in a homogeneous isotropic, thermally and electrically conducting, uniformly rotating elastic half-space, in contact with vacuum, due to (i) normal load and (ii) impulsive load, at the plane boundary, in the context of generalised theory of thermoelasticity. The Laplace transform on time has been used to obtain the solutions. Because ‘second sound’ effects are short-lived, so small time approximations have been considered. The standard results of the previous investigations have also been deduced as particular cases.

We studied the effect of indomethacin, a cyclooxygenase inhibitor, on bradykinin-induced responses in the intact and denuded epithelium of the isolated tracheal smooth muscle in guinea pigs. Epithelium removal alone did not alter the responsiveness to bradykinin. Indomethacin (2.8 microM) enhanced the sensitivity to bradykinin of both intact and denuded preparations. This finding suggests that the tracheal epithelial may have no protective effect on the contractile responses induced by bradykinin. This may be due to the presence of high amounts of bradykinin-inactivating enzymes in the tracheal smooth muscle. Indomethacin-medicated potentiation caused by bradykinin in epithelium intact and denuded preparations may be an indication of removal of the bronchodilator prostaglandin biosynthesis. The significance of these findings is discussed.

The paper concentrates on the study of reflection characteristics of acoustodiffusive waves from the surface of a semiconductor halfspace which is subjected to stress free, isoconcentrated and stress free, impermeable conditions. The effect of life and relaxation times of charge carriers (electron or holes) fields on the wave characteristics is also investigated. The amplitude ratios (reflection coefficients) of reflected waves to that of incident wave are obtained for incident quasilongitudinal (qP), quasitransverse (qSV), and electron-(N) and hole (P) wave cases. The special cases of normal and grazing incidence are also derived and discussed. Finally, the numerical computations of reflection coefficients are carried out with the help of Gauss elimination method by using MATLAB programming software. The computer simulated results in respect of stress free conditions have been plotted graphically for silicon (Si) and presented in tabular form in case of germanium (Ge) semiconductors. The study may be use...

Kinins are potent mediators of rheumatoid inflammation. The components of the kinin-forming system are hyperactive in RA. Excessive release of kinins in the synovial fluid can produce oedema, pain and loss of functions due to activation of B1 and B2 receptors. These receptors could be stimulated via injury, trauma, coagulation pathways (Hageman factor and thrombin) and immune complexes. The activated B1 and B2 receptors might cause release of other powerful non-cytokines and cytokines mediators of inflammation, for example, PGE2, PGI2, LTs, histamine, PAF, IL-1 and TNF derived mainly from polymorphonuclear leukocytes, macrophages, endothelial cells and synovial tissue. These mediators are capable of inducing bone and cartilage damage, hypertrophic synovitis, vessels proliferation, inflammatory cells migration, and possibly angiogenesis in pannus formation. These pathological changes, however, are not yet defined in human model of chronic inflammation (RA). Hence, the role of kinin and its interacting inflammatory mediators would soon start to clarify the detailed questions they revealed in clinical and experimental models of chronic inflammatory joint diseases. Several B1 and B2 receptor antagonists are being synthesized in an attempt to study the molecular functions of kinins in inflammatory processes (RA, periodontitis and osteomyelitis), and they represent and important area for continued research in rheumatology. Future development of specific, potent and stable B1 and B2 receptor antagonists or combined B1 and B2 antagonists with y-IFN might serve as pharmacological basis of more effective rationally-based therapies for RA. This may lead to significant advances in our knowledge of the mechanisms and therapeutics of rheumatic diseases.

We have evaluated the effects of a B2 receptor antagonist (B5630) of kinins on BK and captopril-induced acute hypotensive responses in anaesthetized SHR. Intravenous treatment of BK (1.0 microgram) and captopril (0.3 mg/kg) caused significant (p0.05) fall in the SBP and DBP. Whereas BK caused greater fall in the SBP (p0.05), DBP (p0.01) and duration of hypotension (p0.05) when administered after captopril (Fig 1 and 2). All the hypotensive effects of BK and captopril were significantly antagonised (p0.05) in the presence of B5630 (2.0 mg/kg). Further, the duration of hypotensive responses of BK and captopril were blocked (p0.05) by B5630. The agonists and BK-antagonist did not cause significant (p0.05) alterations in HR during the entire investigation. These findings provide evidence to support the suggestion that B2 receptor might be involved in the regulation of the hypotensive actions of BK and captopril. Kinins should also have valuable functions in the antihypertensive property of captopril-like drugs.

Components of the kallikrein-kininogen-kinin are activated in response to noxious stimuli (chemical, physical or bacterial), which may lead to excessive release of kinins in the synovial joints that may produce inflammatory joint disease. The inflammatory changes observed in synovial tissue may be due to activation of B2 receptors. Kinins also stimulate the synthesis of other pro-inflammatory agents (PGs, LTs, histamine, EDRF, PGI2 and PAF) in the inflamed joint. B2 receptor antagonists may provide valuable agents as new analgesic drugs. Further, it is suggested that substances directed to reduce the activation of KKS may provide a pharmacological basis for the synthesis of novel anti-rheumatic or anti-inflammatory drugs.

Thirty-five patients with uncomplicated hypertension were observed for blood pressure behaviour after prolonged antihypertensive medication withdrawal. Twenty-three patients (Group 1) remained normotensive (systolic less than 140 mmHg, diastolic less than 95 mmHg) for over 60 weeks compared to 12 patients (Group 2) who became hypertensive again during a 4-week placebo period. Discriminant analysis was performed on 31 clinical and laboratory variables measured before therapy to separate any discriminating factors for the two groups. Four variables maximized the separation of Group 1 from Group 2 patients. In descending order, these were serum sodium (p less than 0.001), mean corpuscular volume (p less than 0.01), serum albumin (p less than 0.01), and body weight (p less than 0.05). Using these four variables 73.9% of patients in Group 1 and 75% of patients in Group 2 were classified correctly into their respective groups. It is suggested that this observation may be useful in the development of new therapeutic regimens for patients with uncomplicated essential hypertension, for example by predicting those patients who may respond favourably to intermittent therapy or even to its withdrawal.

The distribution of deformation, temperature, and magnetic field in a homogeneous isotropic, thermally and electrically conducting, elastic half-space, in contact with the vacuum, has been investigated by taking (i) a step in stress and (ii) a thermal shock, at the plane boundary, in context of generalised theory of thermoelasticity. The Laplace transform on time has been used to obtain the solutions. Because the “second sound” effects are short-lived, so the small time approximations have been considered. The deformation is found to be continuous at the wavefronts whereas the perturbed magnetic field and the temperature are found to be discontinuous in the case of normal load. In case of thermal shock the displacement is continuous but temperature and magnetic field are discontinuous at the wave fronts.

Systolic blood pressure responses to enalapril maleate (MK 421, a new angiotensin converting enzyme inhibitor (CEI)) and hydrochlorothiazide (HTZ) were studied in conscious Dahl salt-sensitive (DS) and salt-resistant (DR) rats maintained on a high salt (8.0% NaCl) and a normal salt (0.4% NaCl) diet. The DS rats were severely hypertensive after 3 weeks on the high salt diet whereas the systolic blood pressure (SBP) of the DR rats were normotensive. Oral treatment with enalapril (15–100 mg∙kg−1∙day−1) and HTZ (60–400 mg∙kg−1∙day−1) caused a significant reduction of SBP in the DS rats with the high salt diet (P < 0.001); however, this was not observed until after 4 weeks of treatment when the dosage was 30 and 150 mg∙kg−1∙day−1, respectively. Furthermore, enalapril therapy alone significantly reduced the SBP of all groups of rats regardless of diet or Dahl strain (P < 0.001), but this was not observed until the end of the 7th week of therapy in DR rats on 8.0% NaCl and the end of the 3rd week of therapy for DR and DS rats on 0.4%) NaCl. These results suggest that enalapril may lower SBP by mechanisms other than those related to an action as a CEI.

SummaryAtrial tamponade was used as a method to reduce atrial transmural pressure in dogs whose afferent pathways from cardiac receptors were interrupted by sympathectomy and vagotomy. Under these conditions, atrial tamponade caused decreases in renal sodium excretion and urine flow which were comparable to those previously observed in intact dogs. These observations lead us to conclude that the changes in renal function which occur during atrial tamponade are not caused by a reflex initiated by atrial receptors. Rather, the alterations in renal function appear to be attributable to unidentified changes in systemic hemodynamics that are elicited by atrial tamponade.

This paper deals with the solution of the wave parameter identification problem for ocean test structure data. A continuous formulation is assumed. An ocean test structure is considered, and wave elevation and velocities are assumed to be measured with a number of sensors. Within the frame of linear wave theory, a Fourier series model is chosen for the wave elevation and velocities. Then, the following problem is posed: Find the amplitudes of the various wave components of specified frequency and direction, so that the assumed model of wave elevation and velocities provides the best fit to the measured data. Here, the term best fit is employed in the least-square sense over a given time interval. At each time instant, the wave representation involves three indexes (frequency, direction, instrument); hence, three-dimensional arrays are required. This formal difficulty can be avoided by switching to an alternative representation involving only two indexes (frequency-direction, instrument); hence, standard vector-matrix notation can be used. Within this frame, optimality conditions are derived for the amplitudes of the assumed wave model. Numerical results are presented. The effect of various system parameters (number of frequencies, number of directions, sampling time, number of sensors, and location of sensors) is investigated in connection with global or strong accuracy, local or weak accuracy, integral accuracy, and condition number of the system matrix. From the numerical experiments, it appears that the identification problem has a unique solution if the number of directions is smaller than or equal to the number of sensors; it has an infinite number of solutions otherwise. In the case where a unique solution exists, the condition number of the system matrix increases as the size of the system increases, and this has a detrimental effect on the accuracy. However, the accuracy can be improved by proper selection of the sampling time and by proper choice of the number and location of the sensors.

This paper deals with the solution of the wave parameter identification problem for ocean test structure data. A discrete formulation is assumed. An ocean test structure is considered, and wave elevation and velocities are assumed to be measured with a number of sensors. Within the frame of linear wave theory, a Fourier series model is chosen for the wave elevation and velocities. Then, the following problem is posed: Find the amplitudes of the various wave components of specified frequency and direction, so that the assumed model of wave elevation and velocities provides the best fit to the measured data. Here, the term best fit is employed in the least-square sense over a given time interval.

Plasma kininogen levels in the peripheral venous blood of untreated patients with active rheumatoid disease was found to be more than twice the levels measured in healthy normal individuals or in convalescing uncomplicated fracture patients. Treatment with oral indomethacin or aspirin lowered the kininogen levels nearly to normal. Sequential studies showed that the fall in kininogen was very rapid, occurring within 1-2 hours of ingestion of drug, and was parallelled by reduction in the clinical indices of inflammation. Control studies showed that the kininogen changes were not due to changes in plasma volume or non-specific changes in plasma protein concentration. Indomethacin treatment had no effect on plasma kininogen levels in healthy volunteers. The significance of this finding will be discussed.

The Dahl salt resistant (DR) rat maintained on a low, 0.4%, or a high 8.0% salt-diet remained normotensive. The bradykinin (BK) induced falls in the systolic (SBP) and diastolic (DBP) were unaffected (P greater than 0.05) by the presence of indomethacin (5 mg/kg). Indomethacin, however, caused a substantial (P less than 0.001) reduction in the duration of the hypotensive action of bradykinin. It is speculated that the indomethacin effects result from an inhibition of the cyclooxygenase system in DR rats.

Enalapril maleate (MK 421), and hydrochlorothiazide were used to evaluate the control of hypertension and reversal of myocardial hypertrophy in Dahl sensitive (DS) and Dahl resistant (DR) rats given either a high (8% NaCl) or a low salt (0.4% NaCl) diet. Groups of six-week-old male DS and DR rats were treated with enalapril (15-100 mg/kg/day) in drinking water for eight weeks. Additional comparable groups of DS and DR were also treated with hydrochlorothiazide (60-400 mg/kg/day). Systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR) and heart weight/body weight (Hwt/Bwt) ratio were determined. We observed significant reduction in Hwt/Bwt ratio (P less than 0.001) along with control of SBP and DBP in the DS given a high salt diet treated with either enalapril or hydrochlorothiazide. However, in the DR given a high salt diet, cardiac regression (Hwt/Bwt ratio, P less than 0.05), SBP and DBP (P less than 0.01) reduction were seen only with enalapril. Similarly, cardiac regression (Hwt/Bwt ratio, P less than 0.05) was observed along with reduction of SBP and DBP (P less than 0.001) in the DS given a low salt diet and DR given enalapril. These data indicate that enalapril reduced SBP and DBP in association with cardiac regression in hypertensive and normotensive rats. In contrast, hydrochlorothiazide only reduced SBP, DBP and caused cardiac reversal (Hwt/Bwt ratio) in DS placed on a high salt diet.

For pt.II see Phys. Status Solidi a, vol.57, p.30 (1980). An electrocodeposition method is described for obtaining films of a cationically substituted AgI-based superionic solid (NH4Ag4I5) on a silver substrate. The electrical conductivity of various thickness films and films prepared under different conditions are reported at different temperatures. The best films are obtained when electrolysis is carried out at 40 degrees C. These results are compared with the results of best RbAg4Ag4I5 and KAg4I5 superionic solid films obtained by the authors earlier using a similar method.

Introduction Since the observation of its hypotensive effect by FREY in 1926 [1], the kinin-forming system has provided a consistent interest to pharmacologists who have attempted to define a possible role of this agent in several physiopathological conditions, especially in hypertension. A relationship between kinin-generating system and hypertension was first described in 1934 by ELLIOTT and NUZUM [2]. These investigators observed sub-normal urinary kallikrein concentrations in essential hypertensive patients. This finding received greater attention after 37 years, when MAR~OLItlS et al. [3] reported altered urinary kallikrein excretion in human hypertension. The most prominent hypotensive actions of kinins are vasodilator in most areas of circulation and decrease in total peripheral resistance [4-6], and regulation of sodium excretion from the kidney [7-10]. Infusion of low concentrations of bradykinin (0.005-0.2 ag/kg per min) into renal artery of anaesthetized dog produces a natriuresis and diuresis by increasing renal blood flow [4, 11]. These effects might be due either to prostaglandins (PG's) release within the kidney [12, 13] or to a direct action on renal handling of sodium and water [14]. Recently, the renal kallikrein-kinin system has been proposed as a mediator involved in control of local blood flow, water and electrolyte excretion and blood pressure [15]. Furthermore, the amount of kallikrein present in urine has been taken as an indicator of renal activity of the system because it origates from the kidney [16, 17]. This brief review, therefore, is intended to summarize the modern concept of the kallikrein-kininogen-kinin system (KKKS) in hypertensive crises.

The distribution of quinidine in the heart is relatively higher in the ventricles than in the auricles. The intracellular localization of the drug in the left ventricular tissue reveals that the nuclear fraction binds the maximum, the supernatant fraction being the next while the sarcosomal fraction shows insignificant affinity. Liver tissue, in contrast, shows that the supernatant fraction retains the highest concentration, whereas the nuclear and mitochondrial fractions share about equal amounts. The separation of the microsomal fraction has not been accomplished. Physico-chemical studies demonstrate that the binding of quinidine to the nuclear fraction is rather a “physical” process. Quinidine in the supernatant fractions of both heart and liver has been shown to be associated with the cytoplasmic proteins.

The genusZinnia L. is comprised of 17 species of annuals, perennials and shrubs, distributed primarily in North and Central America, but with one species in South America. The genus is organized into two subgenera,Diplothrix, comprised of six perennial, cespitose species (none of which are in cultivation), andZinnia, comprised of two sections,Zinnia, comprised of three annual species, andMendezia, comprised of 8 species of annuals and perennials. Members of sectionZinnia are the most important horticulturally. The genus is the source of the very popular garden annual zinnias, the multitudinous forms of which are based primarily upon Z.elegans Jacq., which was first brought under cultivation in Europe in the late 18th Century. Most of the forms currently cultivated have been derived from the very limited amount of germ plasm represented by this initial and a few subsequent introductions without repeated recourse to new germ plasm from natural populations. It is remarkable that such a diversity of cultigens should have been derived from such a limited amount of starting material, but this appears to be characteristic of a number of Western Hemisphere genera first brought under domestication in Europe. Z.haageana Regel (sectionZinnia) and Z.angustifolia (sectionMendezia) have been the sources of a much more limited array of cultigens than has Z.elegans. The other 14 species ofZinnia have contributed little or nothing to horticulture, but are regarded as potentially valuable sources of new germ plasm for further diversification of flower form, color, and plant habit, as well as resistance to diseases, insects and viroses. Cytologically, the genus is polybasic, with x = 10, 11, 12. Recent detailed studies of the subgenusDiplothrix by Torres and co-workers have shown that the three diploid species (Z.juniperifolia, Z. acerosa, Z. oligantha) possess homologous genomes and that their karyotypes are indistinguishable. Several chromosomal races of the diploids have been detected, the tetraploid ones having arisen through either auto- and allopolyploidy. The tetraploid species (Z.citrea,Z. grandiflora) are believed to be segmental allotetraploids derived from the diploids, while the single octoploid species (Z.anomala) is believed to be derived from Z.grandiflora. The subgenusZinnia has not been studied as intensively, but might well prove to be equally diverse. Depending upon circumstances, these cytological variations could either complicate or facilitate the use of additional species material in floricultural breeding programs. In any case, there exists ample material for genetic studies. The cultivated zinnias, especially those based upon Z.elegans, are readily organized into a horticultural classification based upon plant height, plant habit, flower size and type, flowering period, and horticultural use. With but slight modification, the same or a similar classification could be used for cultigens derived from other species. Most of the cultivated forms are based on germ plasm introduced into Europe during the latter half of the 18th and forepart of the 19th centuries, and most of the early selection and breeding work was done in Europe. Twentieth Century breeding developments have been achieved mostly in the United States, but some breeding programs are in progress also in India and East Africa. Recent developments have been mostly at the hands of breeders for private seed companies. Innovations in early breeding programs were dependent primarily upon the development of ± pure lines from chance mutants, although difficulty in stabilizing interesting flower forms was, and continues to be frequent. With the advance of breeding technology, the use of induced autotetraploids, male sterility, and marker genes has proven advantageous, and one or more of these mechanisms are almost assuredly involved in the development of recently released first generation hybrid strains. It is the view of the present authors that these, and other techniques, coupled with interspecific hybridization should be capable of making very significant contributions to the further utilization of the large reservoir of germ plasm available in the genusZinnia, with consequent embellishment of gardens coupled with material contributions to the art and science of plant breeding. The same concepts could be applied to other genera of ornamental plants, the germ plasm resources of which may be regarded as equally underutilized.

The present paper is aimed at studying the effects of rotation on the thermoelastic interaction in an infinite Kelvin–Voigt-type viscoelastic, thermally conducting plate rotating about the normal to its faces with uniform angular velocity. This facilitates the decoupling of anti-plane/in-plane motion which is not possible, in general. The upper and lower surfaces of the plate are subjected to stress-free, thermally insulated or isothermal conditions. The formulation is applied according to three theories of the generalized thermoelasticity: Lord-Shulman with one relaxation time, Green–Lindsay with two relaxation times, as well as the coupled theory. Secular equations are derived for the plate in closed form isolated mathematical conditions for symmetric and skew-symmetric wave mode propagation in completely separate terms. In the absence of mechanical relaxations (Rotation and viscous effects), the results for generalized and couple theories of thermoelasticity were obtained as particular cases from the derived secular equations. In the absence of thermomechanical coupling, the analysis for a viscoelastic plate can be deduced from the present one. Finally the numerical solution is carried out for copper material. The function iteration numerical scheme is used to solve the complex secular equations, in order to obtain phase velocity and attenuation coefficients of propagating wave mode. The dispersion curves and attenuation coefficients profiles so obtained for symmetric and skew-symmetric wave modes are presented graphically to illustrate and compare the theoretical results in the presence and absence of rotation. The study may be useful in the construction and design of gyroscopes and rotation sensors as well as in the application in diverse fields.

In this paper, based on three-dimensional linear generalized thermoelasticity, an exact analysis of free vibration of a simply supported homogeneous isotropic, thermally conducting, cylindrical panel with voids initially at uniform temperature and undeformed state has been presented. Three displacement potential functions are introduced for solving the equations of motion, heat conduction and volume fraction field. The purely transverse wave gets decoupled from rest of motion and is not affected by thermal and volume fraction (voids) fields. After expanding the displacement potentials, volume fraction and temperature functions with orthogonal series, the equations of the considered vibration problem are reduced to five-second order coupled ordinary differential equations whose formal solution can be expressed by using Bessel functions with complex arguments. The corresponding results for thermoelastic panel without voids, elastic panel with and without voids have been deduced as special cases from the present analysis. In order to illustrate the analytical results, the numerical solutions of various relations and equations have been obtained to compute the lowest frequency as function of different cylindrical panel parameters. The computer simulated results have been presented graphically.

Summary The plasma theophylline concentrations produced by 4 different slow release formulations, Theograd, Theodur, Theolair-SR and Rona-slophylline were measured over a 24-hr period in 8 healthy subjects. All 4 preparations maintained plasma levels over 12 hr and had similar AUC values when the difference in theophylline content was taken into account. Paired saliva and plasma theophylline concentrations gave a ratio of 1: 0·38, saliva: plasma, but with a large inter and intra individual variation.