Comparisons of scatterometer models for the AMI on ERS-1: thepossibility of systematic azimuth angle biases of wind speed anddirection

There have been many different attempts to develop a model to relate the normalized radar backscatter values for the C-band radars of the active microwave instrument (AMI) on ERS-1 as a function of 10-m wind speed, azimuth angle, which is wind direction relative to radar-beam direction and incidence angle. The first two models, namely CMOD-1, Long (1985) and CMOD-2, are analyzed, and modifications of them are used to show by means of Monte Carlo methods that it is important to be able to define the backscatter model for all azimuth angles in addition to obtaining good agreement at upwind, downwind, and crosswind relative to the radar-beam direction. Methods are described to compare one model to another and to show how to systematic discrepancies, which are the result of model differences, can be found. These discrepancies are also expected when various models are employed to recover winds from real backscatter data. Discrepancies between a model and an unknown “true” model can introduce systematic biases in the recovered wind vectors as opposed to random errors, which result from sampling variability. The validation of the vector winds from scatterometer data requires a comparison of these winds with accurate conventionally measured winds. The data buoys deployed by various nations can serve as the appropriate data because ship reports are not accurate enough     

An analog front-end signal processor for a 64 Mbits/s PRMLhard-disk drive channel

This BiCMOS IC contains all the analog front-end components necessary for the design of a 21-64 Mb/s HDD channel. Major functional blocks include an automatic gain control circuit having both analog and digital modes of operation, a programmable filter with 6-33 MHz bandwidth range, two phase-locked loops with 24-72 MHz center frequency ranges, a differential 6 bit flash A/D converter with 24-72 MHz sampling rates, and a write precompensator having 600 ps step size     

2-(1-Naphthyloxy)ethylamines with enhanced affinity for human 5-HT1D beta (h5-HT1B) serotonin receptors

Although the beta-adrenergic antagonist propranolol (1) binds at rodent 5-HT1B serotonin receptors, it displays low affinity (Ki > 10,000 nM) for its species homologue 5-HT1D beta (i.e., h5-HT1B) receptors. The structure of propranolol was systematically modified in an attempt to enhance its affinity for the latter population of receptors. Removal of the alkyl hydroxyl group, shortening of the O-alkyl chain from three to two methylene groups, and variation of the terminal amine substituent resulted in compounds, such as N-monomethyl-2-(1-naphthyloxy)-ethylamine (11; Ki = 26 nM), that display significantly higher h5-HT1B affinity than propranolol. Compound 11 was shown to bind equally well at human 5-HT1D alpha (h5-HT1D) receptors (Ki = 34 nM) and was further demonstrated to possess h5-HT1B agonist character in an adenylate cyclase assay. It would appear that such (aryloxy)alkylamines may represent a novel class of 5-HT1D receptor agonists.     

Cytogenetic abnormalities in B-immunoblastic lymphoma

We have considered the cytogenetic abnormalities present in 27 unpublished cases of B-immunoblastic lymphoma. Among these 27 patients, the chromosome changes were heterogeneous and complex. The chromosomes most commonly gained were 3 (44% of cases), 18 (44%), 6 (30%) and 11 (30%). The most common structural abnormalities involved band 14q32 (26%), band 18q21 (15%) and bands 6q16-21 (19%). Study of these 27 immunoblastic lymphomas did not allow us to tentatively identify a common primary cytogenetic abnormality unique to B-immunoblastic lymphoma, however, a translocation at 14q32 may be the primary cytogenetic lesion in some of the cases. Rather, we have added to the number of abnormalities reported in immunoblastic lymphoma and in non-Hodgkin's lymphoma in general.     

Primary total hip reconstruction with a titanium fiber-coated prosthesis inserted without cement

A prospective study was done of the intermediate-term clinical and radiographic results of 121 total hip arthroplasties in which a Harris-Galante porous titanium-fiber-coated prosthesis was inserted without cement in 110 patients. The average age at the time of the operation was forty-nine years (range, twenty to seventy years). The average duration of follow-up was sixty-seven months (range, fifty-five to seventy-nine months). The average preoperative Harris hip score was 55 points, and the average postoperative score was 93 points. One acetabular component was revised due to recurrent dislocation. Eleven femoral implants were unstable, and of these, four were revised. Cortical erosion was present around the distal part of the femoral stem in nine patients (8 per cent) who had stable implants, and one of these femoral implants was revised because the erosion was extensive. Survivorship analysis at five years revealed a 97 per cent chance of survival (95 per cent confidence limit, 0.937 to 1.0) of the Harris-Galante femoral-stem implant inserted without cement.     

Systematic organization of body-composition methodology: an overview with emphasis on component-based methods

The field of body-composition research currently lacks a systematic organization of methods used to quantitate components at the atomic, molecular, cellular, tissue-system, and whole-body levels of body composition. In this report we propose a classification system for body-composition methodology that proceeds in steps, beginning with division of methods into in vitro and in vivo categories, advances to organization by measurable quantity (property, component, or combined), and ends with grouping of methods by mathematical function (types I and II). Important characteristics of component-based methods are then developed, including a classification of component relationship types, the role of ratios and proportions in type II component-based methods, and the basis of simultaneous equations in multicomponent methods. This classification system, the first founded on a conceptual basis, explains similarities and differences between the many diverse methods, provides a framework for teaching body-composition methodology theories to students, and suggests future research opportunities.     

High gain AllnAs/GaAsSb/AllnAs NpN HBTs on InP

We report the first growth and characterization of high gain double heterojunction NpN HBTs on InP with a lattice-matched GaAs₅Sb₅ base layer. This AllnAs/GaAsSb heterojunction has almost no discontinuity in the conduction band edge, eliminating the need to grade the emitter-to-base heterojunction to achieve optimal carrier injection. The layers were grown in a solid source MBE system, using tetramer As₄ and Sb₄ sources. Be is an efficient acceptor in the GaAsSb, but the mobility is about half that measured inp type GaAs on GaAs substrates. The HBTs fabricated were large area mesa isolated transistors, with a beta of 80 at a current density of 2 kA/cm², and the gain remained high at lower current densities. The turnon voltage,V _be, is only 0.45 V at a current density of 2 A/cm².     

Bioactivity of mango flesh and peel extracts on peroxisome proliferator-activated receptor γ [PPARγ] activation and MCF-7 cell proliferation: fraction and fruit variability

Mangos are a source of bioactive compounds with potential health promoting activity. Biological activities associated with mango fractions were assessed in cell-based assays to develop effective extraction and fractionation methodologies and to define sources of variability. Two techniques were developed for extraction and fractionation of mango fruit peel and flesh. Liquid chromatography-mass spectrometry (LC-MS) was used to assess compositional differences between mango fractions in flesh extracts. Many of the extracts were effective in inhibiting the proliferation of human breast cancer cells in vitro. All fractions showed bioactivity in PPAR activation assays, but quantitative responses showed marked fruit-to-fruit variability, highlighting the need to bulk fruit prior to extraction for activity-guided fractionation of bioactive components. This study also suggests that combinations of diverse molecular components may be responsible for cell-level bioactivities from mango fractions, and that purification and activity profiling of individual components may be difficult to relate to whole fruit effects. Practical Application: Although the health benefits of fruits are strongly indicated from studies of diet and disease, it is not known what role individual fruit types can play, particularly for tropical fruits. This study shows that there is a diversity of potentially beneficial bioactivities within the flesh and peel of mango fruit, although fruit-to-fruit variation can be large. The results add to the evidence that the food approach of eating all components of fruits is likely to be more beneficial to health than consuming refined extracts, as the purification process would inevitably remove components with beneficial bioactivities.     

Nitrite, nitrite alternatives, and the control of Clostridium botulinum in cured meats

Historically, nitrite has been a component of meat-curing additives for several centuries. In recent years the safety of nitrite as an additive in cured meats has been questioned mainly because of the possible formation of carcinogenic nitrosamines. Nitrite has many important functions in meat curing including its role in color development, flavor, antioxidant properties, and antimicrobial activity. The inhibition of Clostridium botulinum growth and toxin production is an especially important antimicrobial property of nitrite. This review discusses the effects of processing, curing ingredients (especially nitrite), and storage of cured meats in relation to the control of C. botulinum. If nitrite is eliminated from cured meats or the level of usage decreased, then alternatives for the antibotulinal function of nitrite need to be considered. Several potential alternatives including sorbates, parabens, and biological acidulants are discussed.     

Light-scattering features of turbidity-causing particles in interconnected reservoir basins and a connecting stream

Light-scattering features of minerogenic particles in interconnected reservoir basins and a connecting stream in the watershed of New York City's water supply system, where these particles dominate scattering, were characterized by scanning electron microscopy interfaced with automated X-ray microanalysis and image analysis (SAX). SAX provided information on composition (in terms of elemental X-rays), shapes, number concentration, size distribution, and projected area concentration (PAV_m) of particle populations. Mie theory calculations based on SAX results were used to estimate the scattering coefficient and the mean scattering efficiency at a wavelength of 660 nm [b_m(660) and <Q_b,m(660)>]. Throughout the study system, nonspherical clay mineral particles in the 1-10 μm size range dominated PAV_m, light scattering and its surrogate, nephelometric turbidity (T_n). Patterns of particle size contributions to b_m(660) (and T_n) remained relatively invariant over a wide range of T_n (more than 200-fold difference). The median size for these contributions was most often ∼2.5 μm. The credibility of the SAX characterizations of the light-scattering features of the minerogenic particles and the calculations based on Mie theory for the study system was supported by (1) the strength of the T_n-PAV_m relationship, (2) the reasonable closure between T_n measurements and calculated values of b_m(660), and (3) the closeness of <Q_b,m(660)> to the limiting value of 2 for polydispersed particle populations. Upstream sources of turbidity-causing particles within the study system were demonstrated to have highly similar light-scattering features. This indicates similar potencies for the particle populations from these sources for turbidity impacts in downstream waters and supports the direct incorporation of T_n measurements into loading calculations to evaluate relative contributions of these inputs with respect to such impacts.