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We present the first results from the upgraded version of the scanning photoemission spectromicroscope MAXIMUM, bared on synchrotron undulator fight and on a multilayer-coated Schwarzschild objective. The upgrade involved nearly all parts of the instrument, notably the beamline and the electron analysis system. Micro-images of Fresnel zone plates and of metal test patterns on semiconductor substrates reached a new record in lateral resolution, well beyond 0.1 micron. The first spectromicroscopy tests were also successfully performed on the new instrument, with analysis of f and d core levels in different systems.

Neuron networks have been imaged with the scanning photoelectron microscope MAXIMUM, showing details in the submicron range such as axons, dendrites and their synapses. These results, obtained with the scanning photoemission microscope MAXIMUM, demonstrate that photoemission can reach the lateral resolution required for the life sciences, and prepare the way to the future use in the life sciences of techniques such as ESCA.

We present the first results of high‐spatial resolution x‐ray imaging studies with an upgraded version of the scanning photoemission multiple application x‐ray imaging undulator microscope. The microscope is a multilayer coated Schwarzschild objective that focuses undulator radiation onto the sample. The recent upgrade improved the spatial resolution by a factor six reaching a full width at half maximum value of 0.5 μm. Highly polished mirrors reduced the diffuse background by almost two orders of magnitude and drastically improved the contrast. The improved microscope was used to perform a series of tests on microgrids and reverse Fresnel zone plates. The microscope capability to detect chemical and topological contrast was verified by using patterned metal overlayers on Si and GaAs substrates. Further improvements to increase the flux and the spatial resolution are underway; this includes the installation of a new undulator beamline.

We describe here a unique lithography beamline that delivers x-rays using a flexible arrangement of two toroidal mirrors (one concave-concave and the other concave-convex), providing high spectral and spatial uniformity at the wafer plane. The image produced is a thin horizontal line, suitable for exposing a 25 by 50 mm field compatible with 0.25 μm VLSI. We also present the current status of the beamline being constructed at CXrl utilizing these optics.

We describe the development of the scanning photoemission spectromicroscope MAXIMUM at the Wisoncsin Synchrotron Radiation Center, which uses radiation from a 30-period undulator. The article includes a discussion of the first tests after the initial commissioning.

Publisher Summary This chapter focuses on the obese strain (OS) of chickens with spontaneous autoimmune thyroiditis as a model for Hashimoto disease. The animal models that develop autoimmune diseases spontaneously parallel the human situation more closely. This is especially true for the OS chickens, which are afflicted with a spontaneously occurring hereditary autoimmune thyroiditis that resembles Hashimoto thyroiditis in most clinical, immunological, and endocrinological aspects. Immunoregulation in the OS is altered at two levels: on one hand there is an intrinsic hyperreactivity of the immune system and on the other, a disturbed interaction between the immune and the neuroendocrine system. The abnormalities intrinsic to the immune system are, for example, reflected in the increased mitogen responsiveness of T cells, the intrinsic hyperproduction of IL-2 and increased expression of IL-2R, the general humoral and cellular hyperreactivity against exogenous antigens, and the occurrence of autoantibodies against nonthyroid antigens, albeit in rather low frequency. T-cell hyperfunction in vitro is complemented by similar observations in vivo, such as increased antiviral responses, accelerated allotransplant rejection, and graft-versus-host reaction.

The Multiple Application X-Ray Imaging Undulator Microscope (or MAXIMUM) is a project being carried out jointly by the University of Wisconsin and the Lawrence Berkeley Laboratory. The principal mode of operation of the system is as a photoemission microscope. In this mode, the radiation from the 30-period undulator on the Aladdin 0.8 GeV storage ring is first passed through a monochromator and then focussed on a pinhole aperture. A 20X demagnified image of this pinhole is formed at the sample plane by a 2-clement microscope objective of the Schwarzschild design, whose surfaces are coated with multilayers to reflect soft x-rays (>77eV). While the diffraction limit of the microscope is around 300 A at a wavelength of 120 A, imperfections in the optics and intensity considerations limit the spatial resolution that can be obtained to about 1000 A. The sample to be studied is positioned at the focus of the microscope and the energy spectra of the emitted photoelectrons are analysed by a cylindrical mirror analyser. In this way it is possible to obtain detailed chemical maps of the specimen, with information on both its chemical components and their chemical status. In this paper we describe the design and operation of the the MAXIMUM beamline, and present some preliminary results obtained with solid state and biological samples.

We recently commissioned the SRC/Vanderbilt University 6‐m toroidal grating monochromator beamline. The problems with mirror heating, signal normalization, monochromator control, and scattered light reduction have led to several innovations on this line, making for a better user interface and adding to the stability and reliability of the final image. We discuss these innovations, and how they affect the user. They include a built‐in laser alignment system, a sapphire windowed gate valve, entrance mirror temperature stabilization, computer automation and control, a beam‐chopper, and the capability of real‐time monitoring of the photon flux during the experiment. We have used noble gas resonance lines to carefully characterize the wavelength resolution of the beamline as a function of energy over a range of beamline parameters. The results demonstrate that by limiting the horizontal width of the image at the slits, and by masking outer portions of the gratings, the flux/bandwidth ratio can be improved at t...

The phenomena of spaceglow and material erosion, which are observed on spacecraft that orbit the earth at low altitudes, are described. Also described are the physical environment of the low earth orbit and the methods by which laboratory research on these phenomena is conducted.

The incidence of ventricular fibrillation during and after temporary experimental occlusion of the left anterior descending coronary artery or its branches was studied in 351 dogs. A standardized procedure of thirty-minute temporary occlusion of this artery was employed in 330. There is usually a critical period after twelve and up to fifteen minutes of ischemia which is characterized by a tendency to arrhythmia: extrasystoles, singly or in runs, ventricular tachycardia, or both extrasystoles and tachycardia if not a fatal ventricular fibrillation. Several instances of transient ventricular fibrillation were observed. Of 239 animals surviving thirty minutes of occlusion, 71 per cent developed ventricular fibrillation immediately after release of the artery, while only 28 per cent of 330 animals developed fibrillation during the occlusion. The re-establishment of blood flow to an area of the myocardium made ischemic for thirty minutes by occlusion of the anterior descending coronary artery is more likely to precipitate ventricular fibrillation than is the period of ischemia itself. Various drugs were evaluated in 324 dogs. Quinidine was the most effective drug in affording protection from ventricular arrhythmia during (7 per cent) and following (47 per cent) occlusion. Procaine, procaine amide and Apresoline offered good protection during the ischemic period. Apresoline and Regitine also reduced the incidence (44 and 37 per cent) of ventricular fibrillation upon reopening the ligature. Of the other drugs tested, only one, pendiomide, showed significant protection (52 per cent incidence). Systemic arterial pressures did not predict the onset of ventricular arrhythmia. Electrical countershock accomplished cardiac resuscitation in 75 per cent of the fibrillating dogs. From these experiments, quinidine appears to be the drug of choice in the prophylaxis of fatal ventricular arrhythmias.

THE remarkable prophylactic and therapeutic value of sulfonamide drugs against certain types of bacterial and protozoan diseases has been amply demonstrated in the domestic fowl. It is not surprising, therefore, that these drugs have been used against pullorum disease by several investigators. Severens, Roberts, and Card (1945) found that certain of the drugs, namely sulfadiazine and sulfamerazine, were quite effective in controlling mortality following the oral inoculation of day-old chicks with broth cultures of S. pullorum, even though feeding of the drugs was delayed for 3 days after inoculation. Similar results have been obtained by Bottorff and Kiser (1947) who fed the drugs for varying periods of time, starting with the day of inoculation. That sulfonamides can be of practical value under field conditions in which the disease has progressed far enough to cause losses and at least the presumptive diagnosis of pullorum disease obtained has been shown by Anderson . . .

SummaryStudies were conducted to assess renal transport functions in chickens which had undergone genetic selection for a high (HUA line) or low (LUA line) incidence of hyperuricemia and articular gout. It was found previously that uric acid secretion was markedly reduced in chickens of the HUA line. In the present studies the rates of glomerular filtration, tubular reabsorption of arginine and glucose, and tubular secretion of tetraethylammonium and creatinine were not significantly different between chickens of the two lines. The rate of secretion of PAH in chickens of the HUA line, however, was approximately 40% of the rate for chickens of the LUA line. These results suggest that renal impairment in hyperuricemic chickens is specific for organic acid transport.

Electron drainage currents from dilute streaming plasmas to positively biased silicon and cadmium sulfide solar cell arrays

Photoemission techniques like electron spectroscopy for chemical analysis are the leading electronic probes in materials science-but their impact in the life sciences has been minimal. A critical problem is that the lateral resolution in ordinary photoemission does not exceed a few tenths of a millimeter. This space-averaged probe is nearly useless for most of the fundamental problems in biophysics and biochemistry, which deal with microstructures in the submicron range or smaller. This limit is being overcome with photoemission microscopes, such as our scanning instrument MAXIMUM. The first scanning photoelectron micrographs of a cellular system with submicron resolution are presented. Minute details of neuron networks are imaged on MAXIMUM, thereby opening the way to novel applications of photoemission in the life sciences. The details include individual neurons, axons, dendrites, and synapses, and composite large-area scanning micrographs were routinely produced with a lateral resolution of 0.5-mu-m.

We present the results of the first test of scanning photoelectron microscopy of biological cells. The results were obtained with the recently commissioned X-ray photoemission microscope MAXIMUM at the Wisconsin synchrotron radiation center, based on an undulator source of photons and on normal-incidence focussing of the photon beam. Several photoelectron micrographs were taken of rate neurons, prepared without metal coating and without labelling agents. The results were compared with visible micrographs produced by the same instrument, and successfully tested for reproducibility over long periods of time.

Photoemission spectroscopy now reaches a lateral resolution in the submicrometer range. It is possible, therefore, to perform chemical analysis in the microscopic domain required for life-science experiments. We present a successful test of this approach, including photoemission spectra taken on microscopic areas of a fixed neuron culture, and photoelectron two-dimensional microdistribution maps of specific elements. The test demonstrates that scanning photoemision spectromicroscopy can be successfully applied to biological specimens, although one cannot automatically connect results on fixed cultures and the in vivo properties.