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This paper focuses on the design, construction, preliminary testing, and potential applications of three forms of miniaturized analytical instrumentation. The first is an optical fiber instrument for monitoring pH and other cations in aqueous solutions. The instrument couples chemically selective indicators that were immobilized at porous polymeric films with a hardware package that provides the excitation light source, required optical components, and detection and data processing hardware. The second is a new form of a piezoelectric mass sensor. The sensor was fabricated by the deposition of a thin (5.5 micron) film of piezoelectric aluminum nitride (AIN). The completed deposition process yields a thin film resonator (TFR) that is shaped as a 400 micron square and supports a standing bulk acoustic wave in a longitudinal mode at frequencies of approx. 1 GHz. Various deposition and vapor sorption studies indicate that the mass sensitivity of the TFR's rival those of the most sensitive mass sensors currently available, though offering such performance in a markedly smaller device. The third couples a novel form of liquid chromatography with microlithographic miniaturization techniques. The status of the miniaturization effort, the goal of which is to achieve chip-scale separations, is briefly discussed.

It is well known that the paraxial propagation of spherical waves through Luneburg’s first-order optical systems is governed by a bilinear relationship—the so-called ABCD law—which relates the curvature of the incoming wave with the curvature of the outgoing wave. It is also well known that this ABCD law applies to completely coherent Gaussian light if we describe such light by its complex curvature. Moreover, it has been shown that the same relationship applies to partially coherent Gaussian light, at least in the one-dimensional case. In this paper we study the behavior of partially coherent Gaussian light in the two-dimensional (or, generally, n-dimensional) case, and we find the conditions under which an ABCD law can again be formulated. It is shown that in such n-dimensional cases an ABCD law holds only for partially coherent Gaussian light for which the matrix of second-order moments of the Wigner distribution function is proportional to a symplectic matrix. Furthermore, it is shown that this is the case if we are dealing with a special kind of Gaussian Schell-model light, for which the real parts of the quadratic forms that arise in the exponents of the Gaussians are described by the same real, positive definite symmetric matrix.

Starting from the well-known description of a first-order optical system by means of its symplectic ABCD ray transformation matrix, a propagation law for the second-order moments of the Wigner distribution function is derived. A matrix is constructed from the second-order moments, which undergoes a similarity transformation when it propagates through a first-order system. This property leads to invariant expressions in terms of the second-order moments, based on the eigenvalues of the matrix mentioned before. Properties of these eigenvalues are derived. It is shown that, at least in the 1-D case, a relation similar to the well known bilinear relationship, which expresses the propagation of the curvature of a spherical wave through a first-order system, can be formulated in terms of the second-order moments. Finally, it is shown that in the higher-dimensional case such a relationship only holds when the second-order moments form a matrix that is symplectic, which is the case for a Gaussian signal, for example.

We have investigated the absorption spectra of seventeen explosives and related compounds (ERCs) by using terahertz time-domain spectroscopy in the 0.1-2.8 THz region. Most of these substances show characteristic absorption features in this frequency range. The measured absorption coefficients of these ERCs form a database, which is of great importance for biochemical, defense and security related applications.

The reflection spectrum of the explosive RDX was acquired from a diffuse reflection measurement using a THz time-domain spectroscopy system in combination with a diffuse reflectance accessory. By applying the Kramers-Kronig transform to the reflection spectrum, the absorption spectrum (0.2-1.8 THz) was obtained. It agrees with the result from a transmission measurement and distinguishes RDX from other materials. The effect of the reference spectrum was examined by using both a Teflon pellet and a copper plate as references. The strong absorption of RDX at 0.82 THz allowed it to be identified by the diffuse reflection measurement even when the RDX sample was covered with certain optically opaque materials. Our investigation demonstrates that THz technique is capable of detecting and identifying hidden RDX-related explosives in a diffuse reflection mode, which is crucial for the standoff detection in the real world applications.

The spatial dependence of spectral and matrix interference effects known to affect ICP emission spectrometry has been studied. The emissions of atoms, ions, and molecules were resolved on both a vertical and radial basis. Interference and sample volatility effects were found to be limited to specific spatial regions. Molecular background emission was dominated by the entrainment of air and was limited primarily to the outer radial regions of the plasma. In contrast, the radial displacement of analyte molecular emission from more slowly atomized samples varied with height. In the case of the easily ionized element interference on Ca atomic/ionic emission, evidence was found indicating at least two different mechanisms of interaction. The ability to attain radial resolution was instrumental in assigning causes to interference effects.

The consequences of using N2 as a nebulizer gas during operation of a direct current plasma were evaluated with respect to its utility as a practical analytical procedure. Performance of the N2 system vs. that of an all-Ar plasma was compared on the basis of background plasma emission, atomization efficiency, detection limits, sensitivity, plasma electron density, and immunity from the easily ionized matrix element interference effect. Observations with regard to the mechanism of the EIE effect were also made. It was concluded in many cases that the use of N2 as a nebulizer gas does not significantly degrade analytical performance. An exception to this conclusion was the finding that refractory samples did not atomize as efficiently in the N2 plasma system.

The observation of molecular fluorescence caused by high-power pulsed laser excitation has been found to be an accurate technique for the determination of relative OH radical concentrations on a spatially resolved basis in a circular air-acetylene flame. It was found that the high power of radiational excitation used allowed fluorescence saturation to be approached. Theory then predicts fluorescence intensities to be independent of temperature and collisional quenching effects. However accurate estimates of relative concentrations can not be obtained unless corrections are made for incomplete saturation and postfilter effects. Procedures for conveniently applying such corrections are reported.

La methode decrite, est basee sur la mesure des legeres modifications de masse, a la surface d'un cristal de quartz piezoelectrique, dues a l'adsorption d'un immunogene sur une surface specialement modifiee. Resultats d'une etude faite avec de l'IgG antihumaine de chaire, immobilisee a la surface de cristaux de quartz piezoelectriques, a l'aide de trimethoxyorganosilane. Les cristaux ont ete places dans le circuit d'un oscillateur electronique et testes pour la detection de l'antigene complementaire humain. Les modifications de masse se traduisent par des changements dans les frequences de resonnance des cristaux

Spatially resolved flame temperatures are spectroscopically measured using the slope method, over small (≃0.7 μl), relatively homogenous volumes of flame gases. The spatial resolution is uniquely obtained by introducing Co as a thermometric species into isolated volumes via the use of a droplet injection technique. By this method the emission of light is restricted to a limited volume, whose position in the flame can be accurately determined and controlled. Vertical resolution is determined by the width of the entrance slit of the monochromator employed (100 μm in this study), and horizontal resolution is limited by the width of the emission cloud formed by the injected droplets (1 to 3 mm). The possibility of self-absorption effects are greatly reduced because of the short radiation path length involved. The performance of the method is illustrated by its application to the spatial temperature mapping of the secondary reaction zone of a cylindrical air-acetylene flame. The effects of N2 as a sheathing gas and flame stoichiometry on the radial and vertical temperature distribution of the flame are also investigated. It is determined that a large, virtually isothermal, central zone exists in the flame.

The measurement of electron temperature and electron density from line and continuum radiation in Ar plasmas used for spectroscopic purposes is discussed. The correct equations for the calculation of these parameters from experimentally observable quantities are identified. Such expressions yield the theoretical spectral irradiance expected from line and continuum radiation. To aid calculations, grouped constants from these equations are calculated using SI units of measure. The sources of accurate values for the parameters and correction factors appearing in the irradiance equations are listed. In addition the approximations made in order to simplify electron temperature and electron density determinations are reviewed. Practical aspects of making accurate measurements of these parameters in Ar plasmas are considered. Theoretical plots of line to continuum emission ratio vs electron temperature and of continuum irradiance vs electron density are presented as an illustration using parameters appropriate for Ar emission at 430 nm and the spectrally adjacent continuum.

A direct reading emission spectrometer system is described which permits dynamic background correction measurements at each analytical wavelength. The system utilizes a refractor plate mounted on a tuning fork as a rapid means for square-wave shifting the spectral band pass from each analytical wavelength to the adjacent background wavelength position. A laboratory computer controls the system, receives the data, and performs the background subtraction. Evaluation of the system has shown that photon counting statistics are applicable and that reliable background corrections are obtained. Comparisons of this correction approach with others that have been used have further demonstrated its advantages for multielement analysis by emission spectrometry.

Description d'un dispositif permettant la speciation de composes mineraux solides. Exemples d'analyses qualitatives et quantitatives de melanges binaires et tertiaires de composes contenant V, Pb, Hg et Cd

Summary The authors present 35 cases of ulcerative colitis, 29 of whom were treated by psychotherapeutic measures. Psychoanalysis was not used in these patients. By a supportive type of treatment the authors tried to give the patient an opportunity to discharge his aggressive feelings and, by giving him constant sympathy and protection, to help him in reasserting himself. Improvement of social conditions, therapeutic influence on attitude of parents, marriage partners, or employers, also appeared to benefit the course of the disease. The realization on the part of the medical and nursing staff that ulcerative colitis patients are immature personalities, who should be treated as such and that the disease itself has contributed to their regression into more infantile feelings and behavior patterns, has been of great importance in bringing out the patience and care which are necessary to obtain satisfactory results. In general, the effect of psychotherapy was determined by the patient's condition on admission, the time and care the doctor was prepared to give to him and the cooperation obtained from the patient's personal environment. It was further found that this type of "superficial" psychotherapy could be carried out equally well by a physician as by a psychiatrist, provided they were interested enough in this sort of treatment. The results compare favorably with those obtained by other forms of treatment.

The present study was undertaken to determine whether there were any differences in the distribution of hepatitis B virus-(HBV) associated serologic markers among hepatitis B surface antigen-(HBsAg) positive first-time and repeat blood donors. The markers examined in samples from 412 newly identified HBsAg-positive donors (254 first-time and 158 repeat) included HBsAg titer and subtype, HBeAg/anti-HBe, and anti-HBc. Repeat donors were more frequently HBeAg-positive (25.9%) than were first-time donors (17.7%). Anti-HBc and anti-HBe were observed more often among first-time (99.6 and 76%) than repeat (91.8 and 60.8%) donors. No differences were found in the mean HBsAg titer nor in the subtype distribution in the two populations. The frequency of HBeAg positivity and the mean HBsAg titer in blood were significantly lower among first-time donors aged 30 or older as compared to those younger than 30. Such age-related tendencies did not occur among the repeat donors. The profiles of HBV makers suggest that the HBsAg-positive first-time donor group consists predominantly of long-term HBsAg carriers who may have acquired HBV at an early age, while the HBsAg-positive repeat donors have newly acquired infections.

The paper presents a review of some applications of the Wigner distribution function to optics. The Wigner distribution function F(x,u) of a signal describes the signal in space x and spatial frequency u, simultaneously, and can be considered as a local spatial frequency spectrum of the signal. Although derived in terms of Fourier optics, the description of a signal by means of its Wigner distribution function closely resembles the ray concept in geometrical optics. Some examples are given to show this resemblance. Properties of the Wigner distribution function are discussed, showing, for instance, its relation to Heisenberg’s uncertainty principle and to some well‐known radiometric quantities. The concept of the Wigner distribution function is not restricted to deterministic signals; it can easily be extended to stochastic signals. Some examples of stochastic signals are considered. The propagation of signals through linear systems can readily be expressed in terms of Wigner distribution functions. Again, the description of systems by Wigner distribution functions can be interpreted directly in terms of geometrical optics: for Luneburg’s first‐order system, for instance, such a description immediately yields the ray transformation matrix of the system, and the relation between the input and the output Wigner distributioin function reads Fo(x,u) = Fi(Ax+Bu,Cx+Du). Transport equations for the Wigner distribution function in a general linear medium are derived. In the Liouville approximation they take the form of a first‐order partial differential equation, which allows, once more, a geometric‐optical interpretation: along the path of a geometric‐optical light ray the Wigner distribution function has a constant value.

From January 1975 to December 1978, 19,140,169 units of blood were collected by the American Red Cross at 57 regional locations. Each unit was tested for hepatitis B surface antigen (HBsAg) by a single commercial radioimmunoassay test system. A total of 15,954 donations were reported reactive, representing a rate of HBsAg reactivity of 0.83/1,000 units tested. The rate during 1975 was 0.94/1,000 units tested, decreasing to 0.71/1,000 units tested in 1978 (p0.005). The prevalence of HBsAg among first-time donors was 2.08/1,000 during 1977 and 1978, 2.7 times higher than that calculated for repeat donors (0.77/1,000 donors). Substantial geographic variation in the prevalence and rate of detection of HBsAg was observed.

Traumatizing events and traumatizing conflicts may lead to defense mechanisms which in the course of time become part of character formation. In psychosomatic medicine much attention has been paid in the past to the so-called psychosomatic character profiles. Though discussions about psychosomatic specificity have remained controversial, it still seems advisable to take into account the power of induction of specific defense strategies. In this paper special attention is paid to the fact that asthmatics, patients suffering from hypertension or coronary heart disease, as well as patients suffering from other psychosomatic syndromes, and even patients suffering from carcinoma may induce their own defense strategies in interviewers and therapists, who usually are not sufficiently aware of the fact of such transference phenomena. A distortion of the normal psychotherapeutic process is more often a result of induction processes than has been thought of.

A new antigenic specificity for HBsAg is described, and its usefulness as an epidemiological marker is discussed. This specificity, l, was found in specimens from all geographic areas studied (United States, Latin America, South Africa, the Solomon Islands, and New Guinea). In these areas, l was strongly associated with HBsAg/ay; y-positive, l-negative samples were observed only among specimens from United States volunteer blood donors. This determinant allowed a distinction of HBsAg/ad classes. Thus, the l determinant was detected in 51.4% of HBsAg/adw4, 44.1% of HBsAg/adw(non-w4), and 50% of HBsAg/adr. The association of l and other HBsAg determinants with HBeAg or anti-HBe was also investigated. HBeAg was found to be associated with the presence of the l determinant and with the r determinant. Anti-HBe was associated with the presence of the d and w determinants and with the absence of the l specificity.

During the year 1978 this laboratory evaluated the specificity of all samples found reactive for hepatitis B surface antigen (HBsAg) by 44 of 57 regions of the American Red Cross Blood Services. Radioimmunoassay detected a total of 1.921 HBsAg-reactive sampled among more than three million donor units tested. A vast majority (96%) of the samples had high level of HBsAg (greater than or equal to 20 ng/ml). Only about 50% of the samples with low level of HBsAg (less than 20 ng/ml) were reactive in reversed passive hemagglutination. There were 13 samples that were repeatable for HBsAg but were considered nonspecific as they were nonneutralizable in radioimmunoassay, 2 donors who showed nonspecific reactivity were further tested and it was found that the reactivity in radioimmunoassay persisted for more than 9 months, and this reactivity was also detectable by a second commercial kit for HBsAg. Antibodies to core and surface antigen were not found in any of the nine samples that were tested. The explanation of this nonspecific reactivity is unclear, but the data suggest that the nonspecific factor(s) may be an inherent property of the sample rather than a deficiency of the test reagents.

The complex spectrogram of a signal φ(t) is defined by ∫φ(t)g*(t-to)exp[-iwot]dt ; it is, in fact, the Fourier transform of the product of the signal and the complex conjugated and shifted version of a so-called window function g(t). From the complex spectrogram the signal can be reconstructed uniquely. It is shown that the complex spectrogram is completely determined by its values on the points (to=mT, wo=nΩ), where ΩT= 2tt and m and n take all integer values. The lattice of points (mT,nΩ) is exactly the lattice suggested by Gabor as early as 1946; it arose in connection with Gabor's suggestion to expand a signal into a discrete set of Gaussian elementary signals. Such an expansion is a special case of the general expansion ∑∑mn amng(t-mT)exp[inΩt] of a signal into a discrete set of shifted and modulated window functions. It is shown that this expansion exists. Furthermore, a set of functions is constructed, which is bi-orthonormal to the set of shifted and modulated window functions. With the help of this bi-orthonormal set of functions, the expansion coefficients amn can be determined easily.© (1980) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The American Red Cross collects blood from a number of defined subsets of the donor population and teh proportion of blood collected from each subset varies widely from center to center. A large part of the variation in prevalence of HBsAg may be related to variations in the proportion of blood collected from plants and factories, military units and schools or colleges. We have derived a regression equation, significant at the p less than 0.001 level, which links HBsAg prevalence with these collection parameters. Using this equation, we were able to predict the prevelance of HBsAg among first-time donors in 6 of the 9 geographic divisions of the United States with an accuracy exceeding 10%. The predictions for the remaining division were within 35% of the actual value. Correlation studies were supported by measurements of true donor prevalence in three blood centers.

Microanalysis of the first interview is a technique developed by the author for the subtle translation of the verbal aspects of the doctor-patient contact. Every bit of information, derived from the patient, is translated in the traditional historical dimension, e.g., when did the complaint start, and in the here and now dimension, e.g., in how far does the information imply a cry for help and understanding. Psychosomatic patients, who are usually well adapted, suppress or repress their problems and emotions so much that they are hardly able to express these quite openly. Psychosomatic symptoms reflect the effort of the patient not to behave in a hysterical way. This means that the overt cry for help and attention, which is so characteristic for hysterical patients, is warded off. Especially the microanalytic translation of this hidden cry may be used by the interviewer to detect what the basic problems of the patient are and how the optimal climate for an efficient therapeutic contact can be established. In the Leyden Department of Psychiatry the technique is used to facilitate the training in interview technique. In the paper models will be given for the understanding of the interrelationship of psychiatric and psychosomatic symptoms.