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1.
Rev Sci Instrum ; 80(12): 124501, 2009 Dec.
Article in English | MEDLINE | ID: mdl-20059157

ABSTRACT

Coupling of the solar wind to the Earth magnetosphere/ionosphere is primarily through the high latitude regions, and there are distinct advantages in making remote sensing observations of these regions with a network of ground-based observatories over other techniques. The Antarctic continent is ideally situated for such a network, especially for optical studies, because the larger offset between geographic and geomagnetic poles in the south enables optical observations at a larger range of magnetic latitudes during the winter darkness. The greatest challenge for such ground-based observations is the generation of power and heat for a sizable ground station that can accommodate an optical imaging instrument. Under the sponsorship of the National Science Foundation, we have developed suitable automatic observing platforms, the Automatic Geophysical Observatories (AGOs) for a network of six autonomous stations on the Antarctic plateau. Each station housed a suite of science instruments including a dual wavelength intensified all-sky camera that records the auroral activity, an imaging riometer, fluxgate and search-coil magnetometers, and ELF/VLF and LM/MF/HF receivers. Originally these stations were powered by propane fuelled thermoelectric generators with the fuel delivered to the site each Antarctic summer. A by-product of this power generation was a large amount of useful heat, which was applied to maintain the operating temperature of the electronics in the stations. Although a reasonable degree of reliability was achieved with these stations, the high cost of the fuel air lift and some remaining technical issues necessitated the development of a different type of power unit. In the second phase of the project we have developed a power generation system using renewable energy that can operate automatically in the Antarctic winter. The most reliable power system consists of a type of wind turbine using a simple permanent magnet rotor and a new type of power control system with variable resistor shunts to regulate the power and dissipate the excess energy and at the same time provide heat for a temperature controlled environment for the instrument electronics and data system. We deployed such systems and demonstrated a high degree of reliability in several years of operation in spite of the relative unpredictability of the Antarctic environment. Sample data are shown to demonstrate that the AGOs provide key measurements, which would be impossible without the special technology developed for this type of observing platform.

2.
Insight ; 19(2): 18-22, 1994 Jun.
Article in English | MEDLINE | ID: mdl-8006488

ABSTRACT

This was an investigational process of endophthalmitis in an operating room following cataract surgery. Studies have shown that patients' own skin flora is a prime consideration as a source of endophthalmitis.


Subject(s)
Cataract Extraction/adverse effects , Cross Infection/etiology , Endophthalmitis/etiology , Infection Control/methods , Aged , Aged, 80 and over , Cross Infection/prevention & control , Endophthalmitis/prevention & control , Female , Humans , Male , Middle Aged , Patient Education as Topic
3.
Am J Psychiatry ; 139(4): 431-7, 1982 Apr.
Article in English | MEDLINE | ID: mdl-7065288

ABSTRACT

The authors compared the hypnotic responsivity of 115 chronically ill psychiatric patients with that of 83 nonpatient volunteers. The Hypnotic Induction Profile was administered to all subjects, and diagnoses were established for the patients according to Research Diagnostic Criteria. All of the diagnosed patients (those with thought disorder, affective disorder, generalized anxiety, and miscellaneous disorders) were significantly less hypnotizable than the nonpatient comparison group. This effect was unrelated to age or medication differences. The authors discuss the implication of these findings in relation to a new model of hypnotic responsivity that takes into account the moderating effects of severe psychopathology.


Subject(s)
Hypnosis , Mental Disorders/psychology , Adult , Anxiety Disorders/psychology , Humans , Mental Disorders/drug therapy , Mood Disorders/psychology , Paranoid Disorders/psychology , Psychotic Disorders/psychology , Psychotropic Drugs/therapeutic use , Schizophrenic Psychology
4.
Blood ; 58(2): 309-16, 1981 Aug.
Article in English | MEDLINE | ID: mdl-7248524

ABSTRACT

An in vitro clonal assay for a class of human hemopoietic progenitors (CFU-GEMM) with several characteristics of pluripotential stem cells has been previously described. In the presence of medium conditioned by leukocytes stimulated with phytohemagglutinin (PHA-LCM) and erythropoietin (Ep), CFU-GEMM give rise to mixed hemopoietic colonies containing granulocytic, erythroid, monocyte-macrophage, and megakaryocytic elements. In initial studies we found that CFU-GEMM were present in equal but low frequencies in blood (B) and bone marrow (M) mononuclear cell populations. However, when the culture system was modified by the substitution of Iscove's modified Dulbecco's medium for alpha-MEM and the addition of mercaptoethanol, a significant enhancement of mixed colony formation occurred, and an approximately 3-4-fold difference in the frequency of CFU-GEMM between B and M emerged. Replating studies showed the formation of secondary differentiated hemopoietic colonies and at least a limited capacity for self-renewal of CFU-GEMM. The in vitro growth of normal CFU-GEMM was highly dependent on hemopoietin(s) present in PHA-LCM. In vitro detection of CFU-GEMM, however, requires only relatively low permissive concentrations of Ep, in contrast to the high Ep requirement for optimal BFU-E growth in vitro. These and other data described demonstrate CFU-GEMM to be a distinct multipotential stem cell class whose assay may prove useful in the study of human blood dyscrasias.


Subject(s)
Colony-Forming Units Assay , Hematopoietic Stem Cells/cytology , Cell Differentiation , Culture Media , Erythroblasts/cytology , Erythropoietin/pharmacology , Humans , Macrophages/cytology , Megakaryocytes/cytology , Monocytes/cytology , Phytohemagglutinins/pharmacology
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