An Overview of Progress in the Design And Implementation of Landsat-D Systems

Landsat-D will be launched in late 1981 or early 1982 into a Sun-synchronous orbit near 700 km. Landsat-D systems and the principal observing instrument, the Thematic Mapper, are being designed and implemented to provide a significantly improved Earth-resources monitoring capability. The Thematic Mapper will have seven spectral bands (0.45-0.52, 0.52-0.60, 0.63-0.69, 0.76-0.90, 1.55-1.75, 2.08-2.35, and 10.5-12.5 ?m), with an instantaneous field of view at nadir of 30 m except for the thermal band (120 m). The data from the Thematic Mapper and other Landsat-D flight segment systems will be relayed to the Landsat-D ground data processing system using a direct readout capability or the Tracking and Data Relay Satellite System and communications satellites. The ground systems will process the data as it arrives at rates up to 100 Mbit/s and a total volume of 2.6 × 1011 bit/day into standard digital and photographic products within 48 hours of data acquisition. This includes 200 Multispectral Scanner Subsystem and 100 Thematic Mapper scenes per day. The Thematic Mapper increased spatial, spectral, and radiometric resolution should be of primary benefit in agricultural and vegetation surveys, but substantial improvements in resource and land cover observations for geology, land use, and water resources applications are also to be anticipated.     

Surface markers of human eosinophils

Peripheral blood eosinophils from patients with eosinophilia and from healthy subjects were studied for surface immunoglobulins, receptors for the Fc region of IgG, complement receptors, and spontaneous rosette formation with sheep and mouse erythrocytes. Eosinophils were found to have receptors for complement and for aggregated IgG, and to have the same two types of complement receptors as do lymphocytes and monocytes. Immune adherence type receptors were specific for C4 or C3b, while C3d receptors were specific for C3d but unreactive with C4. Eosinophils differed from fully mature neutrophils in that the former had C3d receptors and relatively weak immune adherence (C4 or C3b) receptors, while the later did not have the C3d receptors and had strong immune adherence receptors. Eosinophil phagocytosis of complement-receptor bound erythrocytes was dependent on the presence of IgG in the antibody coating the red blood cells; this requirement for IgG resembled that found in neutrophil phagocytosis. No surface Ig or spontaneous erythrocyte rosette formation was observed with eosinophils.     

Pancytopenia and aplastic anemia: a retrospective study

During January 1971--June 1975 we examined 195 patients with pancytopenia. The cause was bone marrow failure in 67.7% of cases (classic aplastic anaemia in 11.3%) hypersplenism in 7.7%, massive blood transfusions in 1.5%, severe infections in 9.7% (Gram-negative in 3%), and various other conditions in 7.8%. Records were insufficient for diagnosis in 5.6% of cases. Analysis of the 22 patients with aplastic anaemia showed no apparent aetiology in 16 (72.7%), previous phenylbutazone ingestion in 2, and Fanconi-type anaemia in 4 of 7 children. One-year survival was 73.7%, 2-year survival 71.4%, 3-year survival 63.6% and 4-year survival 57.1%. Marrow-investigation of the 21 available samples showed that 6 were acellular, 11 hypocellular and 4 normocellular. All patients received at least temporary therapy with anabolic steroids but its effectivity could not be satisfactorily assessed. Five patients died within 7 months and 5 patients went into remission, needing no further therapy. The initial haematological features of the 5 patients who died were not significantly different from those of the rest of the patients.     

A time-space tradeoff for sorting on non-oblivious machines

A model of computation is introduced which permits the analysis of both the time and space requirements of non-oblivious programs. Using this model, it is demonstrated that any algorithm for sorting n inputs which is based on comparisons of individual inputs requires time-space product proportional to n².     

Estimated potassium content in Hanford workers

Potassium content in male and female workers at the US Department of Energy Hanford Site was estimated based on measurements made in 2002 of 40K activity in the body. The 40K activity in females ranged from 2.1 to 4.1 kBq with an average of 3.1 +/- 0.02 kBq. The total body potassium (TBK) content in females averaged 98 +/- 0.6 g. The 40K activity in males ranged from 2.8 to 6.6 kBq with an average of 4.2 +/- 0.01 kBq and the average TBK was 136 +/- 0.3 g. The average TBK value for males aged 20-49 y was 140 g. The average TBK values for both genders decreased with age. The average potassium concentrations calculated for the different age ranges for males were 15-25% less than the value (1.9 gK per kg) obtained using the reported ICRP reference potassium and reference weight values. Potassium concentrations were inversely correlated with body-build index, body-mass index and body weight. These correlations could possibly be utilised to help assess the risk for disease. Future work is planned to evaluate whether monitoring of potassium concentrations could be used as a tool for the detection of diabetes and hypertension.     

A Comparative Study of the In Vitro and In Vivo Release of Dexamethasone from a Spray-On Bandage and Timed Release Aerosol

The formulation of several dexamethasone topical delayed release aerosol preparations was studied. Ethylcellulose and tributyl citrate were the film-forming agent and plasticizer, respectively, for the spray-on bandage formulation. The aerosol timed release preparation contained dexamethasone microcapsules suspended in a fluorocarbon aerosol propellant by isopropyl myristate and fumed silica. Both preparations were evaluated using an in vitro method which measured the release of dexamethasone hourly for eight hours. In vitro studies showed that each of the formulations delayed the release of dexamethasone. In the in vivo tests aerosols were sprayed on the unabraded back area of rabbits and the increased 17 - hydroxycorticosteriod urine levels at 24, 48, and 72 hours indicated dexamethasone absorption. In vivo studies indicated that absorption did not occur with the timed release preparation containing dexamethasone microcapsules. However, dexamethasone from the spray-on bandage preparation was absorbed over 72 hours. A commercially marketed topical dexamethasone cream was used for comparison in evaluating the two experimental formulations; however, in vivo studies showed that no absorption occurred with this preparation.

In recent years, a great deal of work has been directed towards the application of medicated polymeric films or tissue adhesives onto the skin to treat minor dermatological problems or serious skin wounds. Among the factors to be considered are: incorporation of a specific active ingredient, the mode of application and the dosage form. Lange and Fang (1,2) developed spray-on bandages using water soluble resins and water as the solvent. Fischl (3) evaluated the effectiveness of a cyanoacrylate monomer in closing skin incisions without affecting wound healing. Bhaskar and Cutright (4) showed that butyl cyanoacrylate could be successfully used as a surface dressing while reducing the degree of inflammation. Sciarra and Gidwani (5,6) reported on the release of gentian violet from selected polymer and plasticizer combinations and established various polymer-plasticizer combinations which could be applied as an aerosol spray. Other studies (7,8) have shown that ethylcellulose and a thermoplastic polyamide resin have potential use in spray-on bandage formulations.

The results indicated that the anti-infectives were released from the films and the spray-on bandages reduced the degree of infection about the wound.

The process of microencapsulation has been applied to various industrial and medical uses. Microcapsules can be prepared so that the encapsulated material will be released slowly. There are various methods of microencapsulation including coacervation, phase separation, interfacial polymerization, an electrostatic method, and vacuum metalization and they have been successfully used with selected drugs (9-13).

The purpose of this study was to develop and evaluate different aerosol formulations containing a therapeutic agent which can be slowly released. In vitro and in Vivo systems were used to evaluate the release and absorption of the drug in the test animals.     

Imprudent linking weaves a tangled Web

Hypertext linking is often embraced uncritically by Web authors eager to explore the power of hypertext without first considering its effects on their readers' comprehension. Hypertext linking is not a substitute for thought-we think with ideas, not with dissociated snippets of raw information. Even the most germane bits of information cannot become ideas, regardless of how cleverly they are stacked, listed or linked. Ideas define relevance, provide context and establish patterns. With patterns, most concepts become intelligible, and we need continuity and stability of theme and context to recognize patterns. So, like most powerful technologies, hypertext links are a mixed blessing. Used improperly, they can be detrimental to Web sites. “Loose links” can drive away an audience, dilute the site's message, confuse the reader with irrelevant digressions and become a continuing maintenance headache for site authors and Webmasters     

POTLIB 2001: A potential energy surface library for chemical systems

POTLIB 2001 is a computer program library of global chemical potential energy surface (PES) functions (91 functions in version 1.0) along with test data, a suite of utility programs, and a convenient user interface. The PES programs are written in ANSI standard FORTRAN77 and can be used to determine the Born-Oppenheimer potential energy of chemical systems as a function of the internal coordinates. The accompanying test data allow users to verify local implementations of this library. Finally, the utility programs permit use of this library in conjunction with a variety of chemical dynamics and chemical kinetics computer codes. Interface routines are provided for the POLYRATE and ABCRATE program packages of Truhlar and co-workers, the VENUS96 program package of Hase and co-workers, and the VARIFLEX program package of Klippenstein and co-workers; the routines in this library can also be used in conjunction with the DYNASOL program package of Zhang and co-workers. This article describes the library and the utility programs and outlines the systematic conventions used for interfaces in the computer programs contained in the library. Adherence to these conventions will allow future PESs to be compatible with this library.