New Evidence on Outlet Substitution Effects in Consumer Price Index Data

In this paper we provide new and detailed evidence on the impact on the U.S. CPI of the appearance and growth of new types of product outlets. Using actual CPI microdata for 2002-2007, we find that the changing mix of outlets had a statistically significantly negative impact on average prices in most of the 14 item food categories we study. In contrast to previous studies of this issue, our approach allows us to examine the effects of changes in outlet mix both across outlet types (such as among large groceries, discount department stores, and warehouse club stores) and within those outlet categories. We also adjust for numerous differences in item characteristics such as brand name, organic certification, and, importantly, package size. In our sample we find that the upward impact on price from increased item quality has offset most of the downward impact of lower-priced outlets. We also provide evidence showing that a simulated “matched-model” approach similar to that used in the CPI yields indexes that differ to a surprising extent from our baseline hedonic indexes, which also hold outlet and item mix constant.Outlet Bias, Consumer Price Index

Genome-wide analysis of the PreA/PreB (QseB/QseC) regulon of Salmonella enterica serovar Typhimurium

<p>Abstract</p> <p>Background</p> <p>The <it>Salmonella </it>PreA/PreB two-component system (TCS) is an ortholog of the QseBC TCS of <it>Escherichia coli</it>. In both <it>Salmonella </it>and <it>E. coli</it>, this system has been shown to affect motility and virulence in response to quorum-sensing and hormonal signals, and to affect the transcription of the <it>Salmonella enterica </it>serovar Typhimurium (<it>S</it>. Typhimurium) <it>pmrAB </it>operon, which encodes an important virulence-associated TCS.</p> <p>Results</p> <p>To determine the PreA/PreB regulon in <it>S</it>. Typhimurium, we performed DNA microarrays comparing the wild type strain and various <it>preA </it>and/or <it>preB </it>mutants in the presence of ectopically expressed <it>preA </it>(<it>qseB</it>). These data confirmed our previous findings of the negative effect of PreB on PreA gene regulation and identified candidate PreA-regulated genes. A proportion of the activated loci were previously identified as PmrA-activated genes (<it>yibD</it>, <it>pmrAB</it>, <it>cptA</it>, etc.) or were genes located in the local region around <it>preA</it>, including the <it>preAB </it>operon. The transcriptional units were defined in this local region by RT-PCR, suggesting three PreA activated operons composed of <it>preA-preB</it>, <it>mdaB-ygiN</it>, and <it>ygiW</it>-STM3175. Several putative virulence-related phenotypes were examined for <it>preAB </it>mutants, resulting in the observation of a host cell invasion and slight virulence defect of a <it>preAB </it>mutant. Contrary to previous reports on this TCS, we were unable to show a PreA/PreB-dependent effect of the quorum-sensing signal AI-2 or of epinephrine on <it>S</it>. Typhimurium with regard to bacterial motility.</p> <p>Conclusion</p> <p>This work further characterizes this unorthadox OmpR/EnvZ class TCS and provides novel candidate regulated genes for further study. This first in-depth study of the PreA/PreB regulatory system phenotypes and regulation suggests significant comparative differences to the reported function of the orthologous QseB/QseC in <it>E. coli</it>.</p

Scope for improved eco-efficiency varies among diverse cropping systems

Global food security requires eco-efficient agriculture to produce the required food and fiber products concomitant with ecologically efficient use of resources. This eco-efficiency concept is used to diagnose the state of agricultural production in China (irrigated wheat–maize double-cropping systems), Zimbabwe (rainfed maize systems), and Australia (rainfed wheat systems). More than 3,000 surveyed crop yields in these three countries were compared against simulated grain yields at farmer-specified levels of nitrogen (N) input. Many Australian commercial wheat farmers are both close to existing production frontiers and gain little prospective return from increasing their N input. Significant losses of N from their systems, either as nitrous oxide emissions or as nitrate leached from the soil profile, are infrequent and at low intensities relative to their level of grain production. These Australian farmers operate close to eco-efficient frontiers in regard to N, and so innovations in technologies and practices are essential to increasing their production without added economic or environmental risks. In contrast, many Chinese farmers can reduce N input without sacrificing production through more efficient use of their fertilizer input. In fact, there are real prospects for the double-cropping systems on the North China Plain to achieve both production increases and reduced environmental risks. Zimbabwean farmers have the opportunity for significant production increases by both improving their technical efficiency and increasing their level of input; however, doing so will require improved management expertise and greater access to institutional support for addressing the higher risks. This paper shows that pathways for achieving improved eco-efficiency will differ among diverse cropping systems

Clinical relevance of "withdrawal therapy" as a form of hormonal manipulation for breast cancer

<p>Abstract</p> <p>Background</p> <p>It has been shown in in-vitro experiments that "withdrawal" of tamoxifen inhibits growth of tumor cells. However, evidence is scarce when this is extrapolated into clinical context. We report our experience to verify the clinical relevance of "withdrawal therapy".</p> <p>Methods</p> <p>Breast cancer patients since 1998 who fulfilled the following criteria were selected from the departmental database and the case-notes were retrospectively reviewed: (1) estrogen receptor positive, operable primary breast cancer in elderly (age > 70 years), locally advanced or metastatic breast cancer; (2) disease deemed suitable for treatment by hormonal manipulation; (3) disease assessable by UICC criteria; (4) received "withdrawal" from a prior endocrine agent as a form of therapy; (5) on "withdrawal therapy" for ≥ 6 months unless they progressed prior.</p> <p>Results</p> <p>Seventeen patients with median age of 84.3 (53.7-92.5) had "withdrawal therapy" as second to tenth line of treatment following prior endocrine therapy using tamoxifen (n = 10), an aromatase inhibitor (n = 5), megestrol acetate (n = 1) or fulvestrant (n = 1). Ten patients (58.8%) had clinical benefit (CB) (complete response/partial response/stable disease ≥ 6 months) with a median duration of Clinical Benefit (DoCB) of 10+ (7-27) months. Two patients remain on "withdrawal therapy" at the time of analysis.</p> <p>Conclusion</p> <p>"Withdrawal therapy" appears to produce sustained CB in a significant proportion of patients. This applies not only to "withdrawal" from tamoxifen, but also from other categories of endocrine agents. "Withdrawal" from endocrine therapy is, therefore, a viable intercalating option between endocrine agents to minimise resistance and provide additional line of therapy. It should be considered as part of the sequencing of endocrine therapy.</p

Astronomical X-Ray Optics Using Mono-Crystalline Silicon: High Resolution, Light Weight, and Low Cost

X-ray astronomy critically depends on X-ray optics. The capability of an X-ray telescope is largelydetermined by the point-spread function (PSF) and the photon-collection area of its mirrors, the same astelescopes in other wavelength bands. Since an X-ray telescope must be operated above the atmosphere inspace and that X-rays reflect only at grazing incidence, X-ray mirrors must be both lightweight and thin, bothof which add significant technical and engineering challenge to making an X-ray telescope. In this paper wereport our effort at NASA Goddard Space Flight Center (GSFC) of developing an approach to making an Xraymirror assembly that can be significantly better than the mirror assembly currently flying on the ChandraX-ray Observatory in each of the three aspects: PSF, effective area per unit mass, and production cost per uniteffective area. Our approach is based on the precision polishing of mono-crystalline silicon to fabricate thinand lightweight X-ray mirrors of the highest figure quality and micro-roughness, therefore, having thepotential of achieving diffraction-limited X-ray optics. When successfully developed, this approach will makeimplementable in the 2020s and 2030s many X-ray astronomical missions that are currently on the drawingboard, including sounding rocket flights such as OGRE, Explorer class missions such as STAR-X andFORCE, Probe class missions such as AXIS, TAP, and HEX-P, as well as large missions such as Lynx

Kinematic Alignment and Bonding of Silicon Mirrors for High-Resolution Astronomical X-Ray Optics

Optics for the next generation's high-resolution, high throughput x-ray telescope requires fabrication of well-formed lightweight mirror segments and their integration at arc-second precision. Recent advances in the fabrication of silicon mirrors developed at NASA/Goddard prompted us to develop a new method of mirror alignment and integration. In this method, stiff silicon mirrors are aligned quasi-kinematically and are bonded in an interlocking fashion to produce a "meta-shell" with large collective area. We address issues of aligning and bonding mirrors with this method and show a recent result of 4 seconds-of-arc for a single pair of mirrors tested at soft x-rays

Research Progress Reports: Fruit and Vegetable Processing and Technology Division, Department of Horticulture [1967]

Evaluation of snap bean varieties for processing / Wilbur A. Gould and William Hildebolt -- Evaluation of various grape cultivars for processing. I. Table wines ; Recommended fruit varieties for canning and freezing / J. F. Gallander -- Evaluation of tomato varieties for processing / W. A. Gould, J. R. Geisman, C. S. Parrott, J. H. McClelland and W. N. Brown -- The effect of different levels of sugar and acid on the quality of apple fruit juice blends / James Gallander and Harold Stammer -- Epidermal sloughing of snap beans as influenced by processing variables / William Hildebolt and W. A. Gould -- Effect of stannous chloride on the color of glass packed kraut / J. R. Geisman -- Proteins and enzymes in the apple fruit in relation to variety and maturation ; Proteins and enzymes in tomato fruits / Robert L. Clements -- Effect of food additives on quality of canned tomatoes / Wilbur A. Gould -- Effects of selective herbicides on the composition and quality of tomatoes / W. A. Gould, J. R. Geisman, E. K. Alban and John Deppen -- Trace levels of pesticide residues in agricultural commodities in marketing channels / W. A. Gould, J. R. Geisman, E. K. Alban, John Deppen, and P. van Pottlesberghe -- Removal of DDT residues by unit operations in preparing and processing spinach / J. R. Geisman, John Deppen and Benita Yao -- The use of chlorine dioxide in handling and holding mechanically harvested tomatoes / J. R. Geisman, Winston D. Bash, Edwin Schmidt, Jr., Linda Hamrick and W. A. Gould -- Effect of mechanical harvesting and handling of tomatoes on quality of canned tomatoes / Wilbur A. Gould, J. R. Geisman, Edwin Schmidt, Jr., John McClelland and W. N. Brow