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The chemical composition of the solar corona is not the same as that of the underlying photosphere. In the corona, elements with a first ionization potential (FIP) of /=10 electron volts (for example, oxygen, neon, and sulfur) by factors of 3 to 10 with respect to the photosphere. The origin of this FIP effect is unknown. The launch of the Extreme Ultraviolet Explorer Satellite (EUVE) opened up the spectroscopic capability required to determine elemental abundances in the coronae of other stars. Spectroscopic observations of the corona of the nearby F5 IV star Procyon obtained with EUVE have yielded estimates of the relative abundances of high- and low-FIP species. The results provide evidence that Procyon, unlike the sun, does not exhibit the FIP effect. Whether the sun or Procyon is more typical of the general late-type stellar population is of fundamental interest to the physics of stellar outer atmospheres and has a bearing on the origin of cosmic rays.

A pancreatoblastoma from a 4-year old male was examined by flow cytometric ploidy analysis and cytogenetics. To detect differences within the tumor, the specimen was divided into four portions and sampled separately. Flow analysis revealed that each sample contained a diploid and a tetraploid population of tumor cells. These findings correlated well with the cytogenetic analysis, which also revealed differences in structural rearrangements between samples. A t(13;22)(q10;q10) was the only rearrangement found in near-diploid cells as well as one near-tetraploid line. Other common structural changes in near-tetraploid cells included t(13;13)(q10;q10), i(6p)(p10), and del(1). Chromosomes 1, 6, 13, and 22 were consistently missing from all near-tetraploid cells lines. To our knowledge, this is the first flow cytometric and cytogenetic study of a pancreatoblastoma.

Five pediatric patients who presented with hip contractures are described. There were 3 boys and 2 girls ranging in age from 7 to 14. None had morning stiffness and one complained of no pain at all. Each had undergone several diagnostic procedures and had seen an average of 2.5 doctors before receiving the diagnosis of arthritis. All were antinuclear antibody negative and HLA-B27 positive, and they had excellent responses to treatment with nonsteroidals and physical therapy. HLA-B27 positive arthritis should be considered in the differential diagnosis of otherwise unexplained hip contractures in children.

108 +/- 11 photons of the martian He 584-angstroms airglow detected by the Extreme Ultraviolet Explorer satellite during a 2-day exposure (January 22-23, 1993) correspond to the effective disk average intensity of 43 +/- 10 Rayleigh. Radiative transfer calculations, using a model atmosphere appropriate to the conditions of the observation and having an exospheric temperature of 210 +/- 20 K, result in a He mixing ratio of 1.1 +/- 0.4 ppm in the lower atmosphere. Nonthermal escape of helium is due to electron impact ionization and pickup of He+ by the solar wind, to collisions with hot oxygen atoms, and to charge exchange with molecular species with corresponding column loss rates of 1.4 x 10(5), 3 x 10(4), and 7 x 10(3) cm-2 sec-1, respectively. The lifetime of helium on Mars is 5 x 10(4) years. The He outgassing rate, coupled with the 40Ar atmospheric abundance and with the K:U:Th ratio measured in the surface rocks, is used as input to a single two-reservoir degassing model which is applied to Mars and then to Venus. A similar model with known abundances of K, U, and Th is applied to Earth. The models for Earth and Mars presume loss of all argon accumulated in the atmospheres during the first billion years by large-scale meteorite and planetesimal impacts. The models show that the degassing coefficients for all three planets may be approximated by function delta = delta (0)(t(0)/t)1/2 with delta (0) = 0/1, 0.04, and 0.0125 Byr-1 for Earth, Venus, and Mars, respectively. After a R2 correction this means that outgassing processes on Venus and Mars are weaker than on Earth by factors of 3 and 30, respectively. Mass ratios of U and Th are almost the same for all three planets, while potassium is depleted by a factor of 2 in Venus and Mars. Mass ratios of helium and argon are close to 5 x 10(-9) and 2 x 10(-8) g/g in the interiors of all three planets. The implications of these results are discussed.

We present the extreme ultraviolet (75-110 angstroms) spectrum of the BL Lac object PKS 2155-304, the first spectrum of an extragalactic source obtained with the Extreme Ultraviolet Explorer. The spectrum shows a generally smooth continuum, which can be modeled by a single power law plus interstellar absorption, and possibly an absorption feature at approximately 80 angstroms. The best fit to the data suggests that the EUV spectrum can be interpreted as a simple extrapolation of the X-ray continuum, with an energy index alpha approximately 1.6; however, shallower or steeper power laws with indices between -0.4 and 2.7 cannot be ruled out by the existing EUV data alone. The data provide strong constraints on the interstellar neutral H and He along the line of sight. Using a column density of 1.36 x 10(20) cm-2 for the Galactic neutral hydrogen along the PKS 2155-304 line of sight, the neutral helium column density is constrained to be 9%-10% of the hydrogen amount.

The first comprehensive sky survey of the extreme ultraviolet (EUV) spectral range performed by the Extreme Ultraviolet Explorer (EUVE) has uncovered a handful of very bright sources at wavelengths longer than the He I 504 angstroms photoionization edge. Among these objects are four white dwarfs with exceptionally low interstellar medium (ISM) column densities along the line of sight. Analysis of EUV photometry of the He-rich DO white dwarf MCT 0501-2858 and the H-rich DA white dwarf MCT 0455-2812 along one line of sight and of the DA white dwarfs HZ 43 and GD 153 near the north Galactic pole indicates that the overall minimum column density of the neutral material centered on the Sun is N(H I)= 0.5-1.0 x 10(18) cm-2. In the case of MCT 0501-2858, EUV photometric measurements provide a clear constraint to the effective temperature (60,000-70,000 K). Given these neutral hydrogen columns, the actual contribution to the density of neutral species from the immediate solar environment (the "local fluff") would only cover a distance of approximately 2-3 pc (assuming an average density n(H I) = 0.1 cm-3) leaving these lines of sight almost entirely within the hot phase of the ISM. A preliminary examination of the complete EUVE long-wavelength survey indicates that these lines of sight are exceptional and set a minimum column density in the solar environment.

The RS CVn binary V711 Tauri was observed by the Extreme Ultraviolet Explorer satellite (EUVE) twice during the latter half of 1992, for periods lasting several days. Light curves for the waveband 60-180 angstroms derived from the all-sky survey scanning in August and from a pointed calibration observation made in October both exhibit a modulation of about 40%. The modulation in both data sets is very similar, with minimum flux occurring near orbital phase phi=0.5. Analysis using a two-temperature optically thin plasma emission model reveals that most of the detected extreme ultraviolet (EUV) flux emanates from hot (approximately 10(7) K) coronal plasma. The modulation is probably mostly due to either flare-like activity or to rotational occultation of a long-lived, compact, and especially bright coronal structure on the more active star of the system. The phased data support the latter hypothesis. This coronal structure is then likely to be associated with the persistent spot patterns seen on V711 Tau when using Doppler and photometric surface imaging techniques. Comparison with contemporaneous Stromgren b-band photometry indicates that the optical minimum light leads the EUV maximum light by 90 degrees in phase.

The extreme ultraviolet wave band (100 to 912 angstroms) was thought until recently to be useless to astronomy, primarily because the opacity of the interstellar medium would prevent observations at these wavelengths. However, the interstellar medium has been found to be markedly inhomogeneous in both density and ionization state and the sun is fortunately located in a region of low extreme ultraviolet opacity. The Extreme Ultraviolet Explorer, launched in June 1992, has surveyed the sky in this wave band and has detected a wide variety of astronomical sources at considerable distances, including some extragalactic objects. Studies in the extreme ultraviolet band have already begun to increase our understanding of the contents of the universe.

We have developed a continuous emission source for use in the soft-x-ray and extreme-UV spectral regions. The source and its characteristics are described.

A small clinical survey was undertaken at East Carolina University School of Medicine to examine the factors which influenced the decisions of five families to continue pregnancies after a chromosomal abnormality was detected. Little has been published concerning the psychosocial effects after continuing pregnancies in which the fetus was diagnosed with a chromosome abnormality by amniocentesis. In order to identify the factors that influenced their decisions, an interview with each couple was undertaken using a 25-part questionnaire. This paper addresses the method of interviewing, case material, and background concerning each couple and the summary of the results.

The approach to rehabilitation management of childhood rheumatic disease differs in many ways from that of adult disease. Among the special considerations are the effects of chronic musculoskeletal inflammation in a growing and developing individual and the tendency of children to tighten their joints into positions of comfort, with fewer problems resulting from ligamentous laxity and instability. A comprehensive management approach includes much more than simply using medications--the tendency for the disease to exert deforming forces on the limbs must be constantly fought by a vigorous program of rehabilitation; education and psychologic support must be provided to the patient and family; potential problems must be discussed with the school; financial and vocational issues must be addressed.

We use a spectrum of the lowest intensity diffuse far-ultraviolet background obtained from a series of observations in a number of celestial view directions to constrain the properties of the extragalactic FUV background. The mean continuum level, IEG = 280 +/- 35 photons cm-2 s-1 angstrom-1 sr-1, was obtained in a direction with very low H I column density, and this represents a firm upper limit to any extragalactic background in the 1400-1900 angstroms band. Previous work has demonstrated that the far-ultraviolet background includes (depending on a view direction) contributions from dust-scattered Galactic light, high-ionization emission lines, two-photon emission from H II, H2 fluorescence, and the integrated light of spiral galaxies. We find no evidence in the spectrum of line or continuum features that would signify additional extragalactic components. Motivated by the observation of steep BJ and U number count distributions, we have made a detailed comparison of galaxy evolution models to optical and UV data. We find that the observations are difficult to reconcile with a dominant contribution from unclustered, starburst galaxies at low redshifts. Our measurement rules out large ionizing fluxes at z = 0, but cannot strongly constrain the QSO background light, which is expected to be 0.5%-4% of IEG. We present improved limits on radiative lifetimes of massive neutrinos. We demonstrated with a simple model that IGM radiation is unlikely to make a significant contribution to IEG. Since dust scattering could produce a significant part of the continuum in this lowest intensity spectrum, we carried out a series of tests to evaluate this possibility. We find that the spectrum of a nearby target with higher NH I, when corrected for H2 fluorescence, is very similar to the spectrum obtained in the low H I view direction. This is evidence that the majority of the continuum observed at low NH I is also dust reflection, indicating either the existence of a hitherto unidentified dust component, or of a large enhancement in dust scattering efficiency in low-density gas. We also review the effects of an additional dust component on the far-infrared background and on extragalactic FUV observations. We conclude that dust reflection, combined with modest contributions from H II two-photon emission and from the integrated light of late-type galaxies, may account for virtually all of the FUV background in low H I column density directions.

Optical spectra have been obtained for a selection of objects included in a catalog of far ultraviolet bright, high galactic latitude objects detected with a balloon-borne survey telescope. The observed objects provide a sample of subdwarf O and B stars, white dwarfs, and binary systems including a hot subluminous member. Model atmospheres analysis of the subdwarf sample is used to determine the temperature, gravity, and helium to hydrogen ratio of the individual objects. A smooth distribution of objects is found on the gravity versus temperature diagram near the theoretical location of the extended horizontal branch. A break between the helium rich and helium poor objects occurs at 40,000 K. Suspected binary objects were found and analyzed to determine the temperature and gravity of the hot subluminous member in each system. The number of subdwarf stars contained in binaries is determined to be from 65% to 100%. The number versus ultraviolet magnitude distribution of the subdwarf B sample is modeled to obtain a midplane density of 3.3 10(-6) pc-3 and a population scale height of 240 pc. The proportion of white dwarfs that experience the subdwarf phase of evolution is found to be 0.94%.

We have determined the scattering parameters of dust in the interstellar medium at far-ultraviolet (FUV) wavelengths (1415-1835 angstroms). Our results are based on spectra of the diffuse background taken with the Berkeley UVX spectrometer. The unique design of this instrument makes possible for the first time accurate determination of the background both at high Galactic latitude, where the signal is intrinsically faint, and at low Galactic latitude, where direct starlight has heretofore compromised measurements of the diffuse emission. Because the data are spectroscopic, the continuum can be distinguished from the atomic and molecular transition features which also contribute to the background. We find the continuum intensity to be well correlated with the Galactic neutral hydrogen column density until saturation at about 1200 photons cm-2 s-1 sr-1 angstrom-1 is reached where tau FUV approximately 1. Our measurement of the intensity where tau FUV > or = 1 is crucial to the determination of the scattering properties of the grains. We interpret the data with a detailed radiative transfer model and conclude that the FUV albedo of the grains is low (<25%) and that the grains scatter fairly isotropically. We evaluate models of dust composition and grain-size distribution and compare their predictions with these new results. We present evidence that, as the Galactic neutral hydrogen column density approaches zero, the FUV continuum background arises primarily from scattering by dust, which implies that dust may be present in virtually all view directions. A non-dust-scattering continuum component has also been identified, with an intensity (external to the foreground Galactic dust) of about 115 photons cm-2 s-1 angstrom-1. With about half this intensity accounted for by two-photon emission from Galactic ionized gas, we identify roughly 50 photons cm-2 s-1 sr-1 angstrom-1 as a true extragalactic component.

A grazing incidence spectrometer was designed to measure the diffuse extreme ultraviolet background. It was flown on a sounding rocket, and data were obtained on the diffuse background between 80 and 650 angstroms. These are the first spectral measurements of this background below 520 angstroms. Several emission features were detected, including interplanetary He I 584 angstroms emission and geocoronal He II 304 angstroms emission. Other features observed may originate in a hot ionized interstellar gas, but if this interpretation is correct, gas at several different temperatures is present. The strongest of these features is consistent with O V emission at 630 angstroms. This emission, when combined with upper limits for other lines, restricts the temperature of this component to 5.5 < log T < 5.7, in agreement with temperatures derived from O VI absorption studies. A power-law distribution of temperatures is consistent with this feature only if the power-law coefficient is negative, as is predicted for saturated evaporation of clouds in a hot medium. In this case, the O VI absorption data confine the filling factor of the emission of f < or = 4% and the pressure to more than 3.7 x 10(4) cm-3 K, substantially above ambient interstellar pressure. Such a pressure enhancement has been predicted for clouds undergoing saturated evaporation. Alternatively, if the O V emission covers a considerable fraction of the sky, it would be a major source of ionization. A feature centered at about 99 angstroms is well fitted by a cluster of Fe XVIII and Fe XIX lines from gas at log T = 6.6-6.8. These results are consistent with previous soft X-ray observations with low-resolution detectors. A feature found near 178 angstroms is consistent with Fe X and Fe XI emission from gas at log T = 6; this result is consistent with results from experiments employing broad-band soft X-ray detectors.

We present measurements of the efficiency and large-angle scattering of a very high line density, mechanically ruled,planar, uniform line-space diffraction grating at extreme ultraviolet wavelengths.

We have investigated the efficacy of a relatively prolonged course of recombinant leukocyte interferon treatment in 14 chronic HBsAg-, HBeAg-, hepatitis B virus DNA- and DNA polymerase-positive carriers. alpha-Interferon was administered for 9 weeks. Six of 14 treated carriers have a sustained loss of HBeAg, hepatitis B virus DNA and DNA polymerase. Four subsequently lost HBsAg (28.5%). Elevated pretreatment SGPT concentrations, histologic chronic active hepatitis, an exacerbation of chronic hepatitis with an increase in SGPT concentrations in the last weeks of treatment and possibly recent onset of the carrier state was associated with complete inhibition of viral replication. None of 11 matched, untreated HBsAg-, HBeAg-, hepatitis B virus DNA- and DNA polymerase-positive carriers monitored during the same period lost HBsAg. The effect of recombinant leukocyte interferon may require an appropriate host-immune response. The efficacy of recombinant leukocyte interferon therapy is restricted, but it may be of benefit in a proportion of carriers, if these carriers can be precisely identified.

Hepatitis B virus (HBV) markers were measured in 83 immunosuppressed renal transplant patients who were followed for periods of 2 to 15 years. Sixty-nine patients were negative for HBsAg before transplantation, of whom 14 were positive for anti-HBs. The remaining 14 patients were HBsAg positive prior to transplantation. Eighteen patients were identified as being HBsAg positive during the follow-up period. Four patients acquired primary type B hepatitis; one died of submassive hepatic necrosis and the remaining three became chronic HBV carriers with positive HBeAg, DNA polymerase, and HBV DNA. Several patterns of HBV expression were observed in HBsAg-positive patients. Four patients were HBsAg, HBeAg, DNA polymerase, and HBV DNA positive prior to transplantation, and these markers persisted. Reactivation of HBV replication occurred in eight patients, seven of whom were HBsAg positive and HBeAg and anti-HBe negative originally; one patient was anti-HBc positive. A single patient was HBsAg and anti-HBe positive and remained so for 22 months. The remaining previously HBsAg-positive patient is currently HBsAg negative. These serological data suggest that reactivation of HBV replication or continued hepatitis B virion replication occurs as commonly or more commonly than de novo infection in renal transplant recipients. The presence of HBeAg in serum predisposes to long-term Dane particle expression in immunosuppressed patients, whereas anti-HBe-positive carriers may not always be susceptible to reactivation of HBV replication despite immunosuppression.

The radiographs of 40 patients with childhood dermatomyositis, an uncommon inflammatory disease, were reviewed. Four distinct patterns of calcification were identified: deep calcareal masses, superficial calcareal masses, deep linear deposits, and a lacy, reticular, subcutaneous deposition of calcium encasing the torso (not emphasized in recent literature). This linear reticular pattern of calcification was associated with a severe unremitting clinical course. Soft-tissue calcification was identified in 40% of cases, a lower incidence than previously reported. No patient in this series had acroosteolysis or pulmonary parenchymal disease, radiographic findings more commonly associated with childhood scleroderma.

Designing optics for photometry in the long-wavelength portion of the EUV spectrum (400-900 A) poses different problems from those arising for optics, operating shortward of 400 A. The available filter materials which transmit radiation longward of 400 A are also highly transparent at wavelengths shortward of 100 A. Conventional EUV optics, with grazing angles of less, similar10 degrees , have very high throughput in the EUV, which persists to wavelengths shortward of 100 A. Use of such optics with the longer-wavelength EUV filters thus results in an unacceptably large soft x-ray leak. We have overcome this problem by developing a mirror design with larger graze angles >/=20 degrees , which has high throughput at wavelengths longer than 400 A but at the same time very little throughput shortward of 100 A.

Sera from 106 southern African blacks with hepatocellular carcinoma and hepatitis B surface antigenemia (HBsAg) were tested for hepatitis B viral DNA (HBV-DNA) activity, HBV-DNA polymerase concentrations, and HBV e antigen (HBeAg) and antibody (anti-HBe) to investigate the state of viral replication in these patients. HBeAg and anti-HBe were detected by radioimmunoassay, HBV-DNA by molecular hybridization using a 32p-labeled HBV-DNA probe, and HBV-DNA polymerase was measured by incorporation of 3H-labeled thymidine triphosphate into double-stranded HBV-DNA. HBeAg was present in 30.2% (32/106) of the patients, almost always in low titer; 63.8% of the patients were anti-HBe positive. Circulating HBV-DNA was detected in 18.8% (20/106) of patients, including 14 of 32 (43.7%) who were HBeAg positive and 6 of 74 (8.1%) who were anti-HBe positive. In most patients, only trace amounts of HBV-DNA were evident. Raised HBV-DNA polymerase activity was found in 5.6% (6/106) of the patients, all of whom were HBeAg positive and 4 of whom had detectable amounts of circulating HBV-DNA. The HBV-DNA polymerase activity was relatively low in these patients. HBV replication thus appears to be present in only a minority of southern African Blacks with HBV-related hepatocellular carcinoma, and when present is of low grade activity.

A four-channel photometer sensitive to two solar EUV lines which are resonantly scattered by helium gas was developed for flight on the Apollo-Soyuz Test Project. Two channels observed the 58.4-nm line of He I and used helium gas resonant absorption cells to determine the intensities of the center and wings of that line. The other two channels observed the 30.4-nm line of He II. The instrument surveyed much of the celestial sphere during a series of slow rolling maneuvers by the Apollo spacecraft. The experiment operated properly, and usable data were obtained. Study of the distributions of flux seen, and of the ratio of 58.4-nm fluxes seen with gas cells full and empty, will refine current understanding of several poorly known properties of the local interstellar medium. Study of the 30.4-nm flux distribution will refine present knowledge of the structure of the earth's plasmasphere.

Skin biopsies from patients with scleroderma and juvenile dermatomyositis (DM) share many histologic features. Characteristics common to both diseases are particularly evident in the dermal microvasculature and include endothelial swelling and concentric thickening of the vascular basement membrane. Biopsies performed on 3 patients with the severe vasculitic form of juvenile DM showed these changes as well as dropout of vessels and linear deposition of collagen. The latter findings, seen late in the course of the disease, are indistinguishable from those of advanced scleroderma. A hypothesis is presented which attempts to relate these histological findings to a common underlying pathophysiologic mechanism.

Two patients in whom asymptomatic and small hepatocellular carcinomas (HCC) were detected by alpha-fetoprotein (AFP) screening are reported. Both patients were hepatitis B surface antigen-positive. In the first patient, the tumour grew slowly and was resected more than 2 years after a significant elevation in serum AFP levels had been first detected and 13 months after hepatic angiography confirmed the presence of a vascular tumour. In the second patient, a small encapsulated HCC was diagnosed by AFP screening and hepatic imaging. The clinical course in these 2 patients illustrates that small, asymptomatic and encapsulated HCCs do occur in southern African black hepatitis B carriers. Regular screening of patients at risk may be justified.

Thin metallic foils of antimony and titanium have been investigated in an attempt to develop an EUV filter with a bandpass from 350 to 550 A. A composite filter has been developed composed of antimony sandwiched between two titanium foils. The transmissions of sample composite foils and of pure titanium foils from 130 to 1216 A are presented. The absorption coefficients of antimony and titanium and the effect of titanium oxide on the transmission are derived. The composite filter has been found to be quite stable and mechanically rugged. Among other uses, the filter shows substantial promise for EUV astronomy.

The highly variable BL Lacertae object Mrk 421 has been observed simultaneously in the radio, optical ultraviolet, and X-ray bands over a period of 4 days in early 1984 December and once again in early 1985 January. Using the EXOSAT observatory, we found that dramatic changes occurred in the X-ray flux on a time scale of less than a mouth. During this time the 2-10 keV flux dropped by a factor of 8, whereas the 0.1-1 keV flux decreased by a factor of only 2. These changes were not reproduced at longer wavelengths during the period of simultaneous observations. However, a drop in the ultraviolet flux occurred some months later, which is consistent with the longer characteristic loss times for the lower energy electrons. Since the ultraviolet through radio flux is stable when the X-ray flux is changing, it is extremely unlikely that a simple synchrotron model can account for the full spectrum; in this model the whole spectrum is expected to rise uniformly and in phase as a result of the injection of energetic particles. A simple synchroton self-Compton model that is self-absorbed in the radio also requires an X-ray flux which is many orders of magnitude greater than is observed. However, this discrepancy may be explained by relativistic beaming of electrons with delta > approximately 40 or by a model in which the self-absorption turnover occurs in the optical, and the synchrotron break occurs in the X-rays. Shorter time scale (approximately 10,000 s) variability was also apparent in the 2-10 keV X-ray light curves, and we suggest that it may be a direct measure of the injection time scale. Although reasonable fits resulted when the X-ray data were compared with a simple power-law model with some absorption, a substantial improvement in chi 2 was obtained by adding a high-energy exponential cutoff. Use of this model produced a spectral index close to that typically found in the optical for BL Lacertae objects, in contrast to the high values usually inferred from X-ray spectra.

We have developed a modified Penning discharge lamp for use in the soft x-ray and extreme uv spectral regions. The source produces a number of intense lines in the 50-300-A range and can be operated for substantial periods of time at high output levels before refurbishment is required. Refurbishment of this source, when required, is very easily effected.

A normal incidence spectrometer for use in the wavelength region from 200 A to 1270 A has been developed. The design and calibration of the instrument are described in detail. The spectrometer can be employed to detect extreme uv radiation at a minimum flux level of 1 rayleigh with a spectral resolution of 40 A and a spatial resolution of 6 degrees . Data on the extreme uv night sky spectrum between 780 A and 1270 A obtained with this instrument on a recent rocket flight are presented.

A satellite-borne extreme-ultraviolet airglow spectrometer is described covering the 275-1420-A range with 8-A resolution. The spectrometer is of near normal incidence Rowland circle design and employs a holographically ruled concave grating. The detector is a microchannel plate with resistive anode providing a continuous readout of any 650-A ground-commandable subset of the total bandpass. This simultaneous wide spectral coverage results in a factor of 80 increase in sensitivity over a fixed exit slit design of equivalent resolution.

Grazing incidence optics are a key element of x-ray and extreme ultraviolet astronomy and are becoming increasingly important in aspects of far-ultraviolet astronomy. Metal optics have figured prominently in this work, and machined metal optics offer distinct advantages in some applications. New methods of metrology have combined with innovations in fabrication to produce metal optics of second of arc quality. In this paper we review the fabrication, evaluation, and performance of machined grazing incidence metal optics produced, or in production, for astronomical telescopes.

Two white females, age 2 1/2 and 33 years, respectively, were investigated because of severe mental retardation associated with neurologic abnormalities, coarse face, and soft tissue syndactyly involving upper and lower limbs. Each had cytogenetic findings of a mosaic variant of Ullrich-Turner syndrome with X ring chromosome in peripheral lymphocyte and skin fibroblasts. Early X replication occurred in one-third of the X ring chromosomes; there was no evidence for X-autosome translocation involving either X and an autosomal duplication; results of studies for fragility of the X chromosomes were unremarkable. In situ hybridization with an X centromere probe was positive for the ring. To our knowledge, the unusual constellation of cytogenetic, physical, and mental findings seen in these 2 individuals has not been reported previously.

Three replica gratings were made from a single master; two were epoxy overcoated with different thicknesses of gold, and one was replicated directly in gold. Their performance in EUV light at grazing incidence angles was measured and compared.

As the presenting complaint in 7 per cent of pediatrician visits, pain in the limbs is a common problem in childhood. It is important that the diagnosis be made expeditiously. The authors review the possible organic cause of limb pain, as well as limb pain from conversion reactions and from growing pains, giving special attention to the differential diagnosis so that appropriate treatment for the pain can be initiated.

Factor VIII related antigen (FVIIIRAg) levels were measured in the plasma of 63 children with rheumatic diseases and 20 controls. High levels were found in patients with systemic juvenile arthritis, systemic lupus erythematosus, dermatomyositis and systemic forms of vasculitis. The amount of circulating FVIIIRAg seemed to be independent of values for erythrocyte sedimentation rate, C-reactive protein and fibrinogen, implying that it was not just another acute phase reactant. Rather, a high level of circulating FVIIIRAg most likely reflects the presence of vascular endothelial injury, and this test may be useful in monitoring disease activity in children with rheumatic diseases in which vasculitis is present.

In view of the rapid evolution of the field of grazing incidence optics, the SPIE organized a conference on the subject in August 1987. Some of the papers given there are published in the 15 April issue of Applied Optics.