Measuring the metastatic potential of cancer cells

Cancer cells must secrete proteolytic enzymes to invade adjacent tissues and migrate to a new metastatic site. Urokinase (uPA) is a key enzyme related to metastasis in cancers of the lung, colon, gastric, uterine, breast, brain, and malignant melanoma. A NASA technology utilization project has combined fluorescence microscopy, image analysis, and flow cytometry, using fluorescent dyes, and urokinase-specific antibodies to measure uPA and abnormal DNA levels (related to cancer cell proliferation) inside the cancer cells. The project is focused on developing quantitative measurements to determine if a patient's tumor cells are actively metastasizing. If a significant number of tumor cells contain large amounts of uPA (esp. membrane-bound) then the post-surgical chemotherapy or radiotherapy can be targeted for metastatic cells that have already left the primary tumor. These analytical methods have been applied to a retrospective study of biopsy tissues from 150 node negative, stage 1 breast cancer patients. Cytopathology and image analysis has shown that uPA is present in high levels in many breast cancer cells, but not found in normal breast. Significant amounts of uPA also have been measured in glioma cell lines cultured from brain tumors. Commercial applications include new diagnostic tests for metastatic cells, in different cancers, which are being developed with a company that provides a medical testing service using flow cytometry for DNA analysis and hormone receptors on tumor cells from patient biopsies. This research also may provide the basis for developing a new 'magic bullet' treatment against metastasis using chemotherapeutic drugs or radioisotopes attached to urokinase-specific monoclonal antibodies that will only bind to metastatic cells

Supersonic laminar-flow control

Detailed, up to date systems studies of the application of laminar flow control (LFC) to various supersonic missions and/or vehicles, both civilian and military, are not yet available. However, various first order looks at the benefits are summarized. The bottom line is that laminar flow control may allow development of a viable second generation SST. This follows from a combination of reduced fuel, structure, and insulation weight permitting operation at higher altitudes, thereby lowering sonic boom along with improving performance. The long stage lengths associated with the emerging economic importance of the Pacific Basin are creating a serious and renewed requirement for such a vehicle. Supersonic LFC techniques are discussed

Spectral and spatial properties of solar microflares

Solar microflares are studied using both hard ( 28 keV) and soft (3.5 to 8.0 keV) X-ray observations. The soft X-ray events have durations 3 m at 0.1x maximum intensity, and typically have similar rise and decay times. The fastest decay observed was 15 s (1/e). Soft and hard X-ray intensities are uncorrelated. The events are very compact, consistent with a projected area approximately 8 x 8 inches. They are normally not associated with H alpha or type 3 emissions and their time profiles suggest a thermal origin at the top of the chromosphere. If the primary energy release site is in the corona, an energy transfer agent consistent with the observations is a non-thermal proton beam

LDR: A Package for Likelihood-Based Sufficient Dimension Reduction

We introduce a new mlab software package that implements several recently proposed likelihood-based methods for sufficient dimension reduction. Current capabilities include estimation of reduced subspaces with a fixed dimension d, as well as estimation of d by use of likelihood-ratio testing, permutation testing and information criteria. The methods are suitable for preprocessing data for both regression and classification. Implementations of related estimators are also available. Although the software is more oriented to command-line operation, a graphical user interface is also provided for prototype computations.

EFFECTIVENESS OF ALTERNATIVE EXPORT PROMOTION STRATEGIES FOR BRANDED FOOD PRODUCTS

This study examines the impact on export sales of various promotional strategies for branded food products in foreign markets. It is an empirical analysis using data obtained from organizations that administer the High Value Export Incentive Program (HVEIP) for branded food products, part of USDA's Targeted Export Assistance (TEA) program and its successor, the Marketing Assistance Program (MAP). To respect the proprietary nature of the data, the identity of individual firms and brand names has been deleted and products have been combined into two groups: (1) consumer ready and (2) intermediate. Economic analysis reveals positive and statistically significant impacts of expenditures on television advertising and advertising in consumer-orientated print media on export sales of consumer ready products, the effect of the latter being somewhat larger. No other promotional strategy reveals a consistent and statistically significant relationship to exports. Channel-orientated strategies seldom showed positive results on export levels for consumer ready products, and consumer-orientated strategies bear no detectable relationship to export levels of intermediate products.International Relations/Trade,

F-14 VSTFE and results of the cleanup flight test program

Flight transition data applicable to swept wings at high subsonic speeds are needed to make valid assessments of the potential for natural laminar flow or laminar flow control for transports of various sizes at various cruise speeds. NASA initiated the variable sweep transition flight experiment (VSTFE) to help establish a boundary layer transition data base for use in laminar flow wing design. The carrier vehicle for this experiment is an F-14, which has variable sweep capability. The variable sweep outer panels of the F-14 were modified with natural laminar flow gloves to provide not only smooth surfaces but also airfoils that can produce a wide range of pressure distributions for which transition location can be determined. The VSTFE program is briefly described and some preliminary glove I flight results are presented

A CROSS-SECTION ANALYSIS OF INTRA-INDUSTRY TRADE IN THE U.S. PROCESSED FOOD AND BEVERAGE SECTORS

This paper analyzes the determinants of variation across industries in levels of intra-industry trade (IIT) for a sample of 36 U.S. processed food and beverage industries in 1987, previous studies of intra-industry trade having focused on industry characteristics in the manufacturing sectors. The determinants predicted by IIT theory are measures of product differentiation, economies of scale, and imperfect competition; the results of this analysis indicate that IIT variation across the food and beverage industries is positively related to product differentiation, U.S. total trade, similarity of tariff barriers among trade partners, and economies of scope, but negatively related to industry concentration.International Relations/Trade,