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At least 433 records · Page 24

Microspheres

Vital information on a person's physical condition can be obtained by identifying and counting the population of T-cells and B-cells, lymphocytes of the same shape and size that help the immune system protect the body from the invasion of disease. The late Dr. Alan Rembaum developed a method for identifying the cells. The method involved tagging the T-cells and B-cells with microspheres of different fluorescent color. Microspheres, which have fluorescent dye embedded in them, are chemically treated so that they can link with antibodies. With the help of a complex antibody/antigen reaction, the microspheres bind themselves to specific 'targets,' in this case the T-cells or B-cells. Each group of cells can then be analyzed by a photoelectronic instrument at different wavelengths emitted by the fluorescent dyes. Same concept was applied to the separation of cancer cells from normal cells. Microspheres were also used to conduct many other research projects. Under a patent license Magsphere, Inc. is producing a wide spectrum of microspheres on a large scale and selling them worldwide for various applications.

Source record↗

Challenges Beyond the Standard Model: An Examination and Evaluation of Alternatives with Respect to Unsolved Problems in Energetics and Signaling

The standard model of particle physics is regarded as one of the greatest achievements of modern physics. It has successfully predicted the existence of numerous hadrons; e.g. the Higgs Boson, the W and Z Bosons, B mesons, etc. Moreover it accurately models many phenomena such as Beta and Radioactive decay, pair production, hadron mass splitting, and others. In spite of this, the standard model has many shortfalls. For example it fails to account for or explain the presence of dark matter and dark energy. Many alternative models of the substructure of matter etc. have been proposed. Some of these are examined. In addition the strongly related standard model of cosmology, that is the big bang theory, accounts for all observed celestial phenomena. What it cannot do is satisfactorily justify all astrophysical events. As noted, dark matter and dark energy are not well understood yet they are core elements of the big bang model. Many elements of this standard model of cosmology are challenged regularly, yet somehow the community always fits the problems with the model into another mysterious element. This model and others are examined for consistency and reconciliation. Evidence of particles that move faster than the speed of light has long been sought, but remains elusive. Some of the known space-like observations of physics are examined. Potential consequences of such particles are likewise investigated. Some conclusions are drawn with respect to the framework of tachyons in a rational but non-rigorous sense. Finally, some of my ideas are presented, concerning all of the above material. The framework of theories of everything is examined, considering what such a theory requires for validity. Sociological notes on the structure of research in physics are given.

Coxe, Alexander M.↗

Compact non-thermal radio emission from B-peculiar stars

Some stars hotter than 10,000 K show propensity for unusual surface abundances and excessive magnetic fields. These peculiar stars, Ap and Bp in the spectral nomenclature, show unusually prominent absorption lines of heavier elements. Rapid rotation and strong magnetic fields are revealed by line shapes and Zeeman splitting. VLBI is here used to directly probe the source size and brightness temperature of weak radio emission recently discovered from two isolated Bp stars, sigma Orionis E and HD37017. The emitting zone for each star is no more than 6 stellar diameters in extent, reflecting brightness temperatures of more than one billion K. Such high surface brightness resembles gyrosynchrotron radiation from mildly relativistic electrons trapped in the strong magnetic fields surrounding these stars. Compact radio radiation from these two stars presents new opportunities for probing the physical environments of early-type stars and for precise radio astrometry.

Phillips, R. B.↗

Development of chip passivated monolithic complementary MISFET circuits with beam leads

The results are presented of a program to demonstrate the processes for fabricating complementary MISFET beam-leaded circuits, which, potentially, are comparable in quality to available bipolar beam-lead chips that use silicon nitride passivation in conjunction with a platinum-titanium-gold metal system. Materials and techniques, different from the bipolar case, were used in order to be more compatible with the special requirements of fully passivated complementary MISFET devices. Two types of circuits were designed and fabricated, a D-flip-flop and a three-input NOR/NAND gate. Fifty beam-leaded chips of each type were constructed. A quality and reliability assurance program was performed to identify failure mechanisms. Sample tests and inspections (including destructive) were developed to measure the physical characteristics of the circuits.

Ragonese, L. J.↗

The Atmosphere Explorer mission.

Summary of the general scientific objectives of the Atmosphere Explorer (AE) mission. The overall purpose of the AE mission is shown to be the performance of simultaneous measurements needed for cause and effect studies that are to provide a detailed understanding of the physical processes governing the lower thermosphere and ionosphere.

Dalgarno, A.↗

Pioneer 11 observations of energetic particles in the Jovian magnetosphere

A preliminary report is presented of energetic electrons and protons observed with the University of Iowa instrument on Pioneer 11. A graph shows absolute, spin-averaged unidirectional intensities of electrons and protons as a function of time during traversal of the central magnetosphere. Another graph shows the effects of the Jovian satellites Io and Amalthea on particle intensities. It is pointed out that a full analysis of satellite effects is the most promising technique for understanding the physical dynamics of the magnetosphere of Jupiter.

Van Allen, J. A.↗

Effects of solid-propellant temperature gradients on the internal ballistics of the Space Shuttle

The internal ballistic effects of combined radial and circumferential grain temperature gradients are evaluated theoretically for the Space Shuttle solid rocket motors (SRMs). A simplified approach is devised for representing with closed-form mathematical expressions the temperature distribution resulting from the anticipated thermal history prior to launch. The internal ballistic effects of the gradients are established by use of a mathematical model which permits the propellant burning rate to vary circumferentially. Comparative results are presented for uniform and axisymmetric temperature distributions and the anticipated gradients based on an earlier two-dimensional analysis of the center SRM segment. The thrust imbalance potential of the booster stage is also assessed based on the difference in the thermal loading of the individual SRMs of the motor pair which may be encountered in both summer and winter environments at the launch site. Results indicate that grain temperature gradients could cause the thrust imbalance to be approximately 10% higher in the Space Shuttle than the imbalance caused by SRM manufacturing and propellant physical property variability alone.

Sforzini, R. H.↗

XPS Study of SiO2 and the Si/SiO2 Interface

X-ray photoelectron spectroscopy (XPS) is analytical technique for understanding electronic structure of atoms close to surface in solids, in preference to bulk structure of material. Study found evidence for core-level chemical shifts arising from changes in local structural environment in amorphous SiO2 and at Si/SiO2 interface. Observed XPS spectra may be understood as sequential convolution of several functions, each with well-defined physical interpretation.

Grunthaner, F. J.↗

Characteristics of the tail of Comet Giacobini-Zinner

The physical structure and characteristics of the Comet Giacobini-Zinner tail are described. Variations in the vector B-field configuration, the electron distribution function, the energetic ion population, and the electromagnetic and electrostatic plasma wave spectra are analyzed. The ICE detected a two-lobe magnetic field configuration and a narrow central plasma sheet. Additional analyses proposed for the Giacobini-Zinner tail data are discussed.

Scarf, F. L.↗

A morphological study of vertical ionospheric flows in the high-latitude F region

The vertical bulk-ion-drift data between 200 and 1000 km, obtained by DE 2 satellite were used to examine ion flows in the high-latitude F region. The data indicated that field-aligned ion flows between 100 m/s and 3 km/s are a common occurrence in the F region. The ion flows were predominantly upward near the cusp region and throughout the auroral zone, with occasionally observed downward flows of smaller magnitude over the polar cap. The results on bulk-ion flows in F region are compared with the published characteristics of the magnetospheric ion outflow, and the possibility that the two flows are physically linked is discussed.

Loranc, M.↗