Laser radiation pressure slowing of a molecular beam

There is substantial interest in producing samples of ultracold molecules for possible applications in quantum computation, quantum simulation of condensed matter systems, precision measurements, controlled chemistry, and high precision spectroscopy. A crucial step to obtaining large samples of ultracold, trapped molecules is developing a means to bridge the gap between typical molecular source velocities (~150-600 m/s) and velocities for which trap loading or confinement is possible (~5-20 m/s). Here we show deceleration of a beam of neutral strontium monofluoride (SrF) molecules using radiative force. Under certain conditions, the deceleration results in a substantial flux of molecules with velocities <50 m/s. The observed slowing, from ~140 m/s, corresponds to scattering ~10000 photons. We also observe longitudinal velocity compression under different conditions. Combined with molecular laser cooling techniques, this lays the groundwork to create slow and cold molecular beams suitable for trap loading.Comment: 7 pages, 7 figures. Supplementary material updated

Lake Erie Grape Farm Cost Survey, 2001-2005

E.B. 2006-19This report is a summary of five years of grape costs and returns data collected from Lake Erie Region grape growers for the 2001-2005 seasons. “Concord” and “Niagara” grapes utilized for juice and generic wine accounted for over 90 percent of the survey acreage. About two-thirds of the acreage surveyed was in New York and one-third from Pennsylvania. In recent years, 42 to 49 growers participated, with total vineyard acreage ranging from about 4,400 to 5,200 acres. Average costs per acre over the entire five year period were $1,663, including an imputed value for the operator’s labor. Major cost categories were paid labor ($380 per acre), depreciation ($213), interest ($114), operator labor ($116) and chemicals ($117). Average yield per farm was 6.4 tons per acre with a range of 2.8 to 8.6 tons per acre. Growers suffered through some difficult circumstances (poor weather, declining prices) over the past five years. Juice grape cash market prices tended to drift down over the course of the five years. National Grape members’ returns moved upward through 2004 and then suffered a severe drop in 2005. Some growers had custom harvesting or other farm income not tied to grape prices. Some growers collected income from crop insurance, disaster payments, and/or Trade Adjustment Assistance (TAA) that helped to buoy income in the face of disappointing yields and unharvested grapes in 2003. However, almost half of the farms who were in the survey for all five years had yields of 7 tons or better. These growers are able to compete with other growing regions such as Washington State. Lake Erie Grape Belt farm managers are responding to lower prices in a variety of ways, including becoming more labor efficient, dropping some poor vineyards (especially leased ones), increasing wine grape production, and increasing farm size

Sum Rules for Magnetic Moments and Polarizabilities in QED and Chiral Effective-Field Theory

We elaborate on a recently proposed extension of the Gerasimov-Drell-Hearn (GDH) sum rule which is achieved by taking derivatives with respect to the anomalous magnetic moment. The new sum rule features a {\it linear} relation between the anomalous magnetic moment and the dispersion integral over a cross-section quantity. We find some analogy of the linearized form of the GDH sum rule with the `sideways dispersion relations'. As an example, we apply the linear sum rule to reproduce the famous Schwinger's correction to the magnetic moment in QED from a tree-level cross-section calculation and outline the procedure for computing the two-loop correction from a one-loop cross-section calculation. The polarizabilities of the electron in QED are considered as well by using the other forward-Compton-scattering sum rules. We also employ the sum rules to study the magnetic moment and polarizabilities of the nucleon in a relativistic chiral EFT framework. In particular we investigate the chiral extrapolation of these quantities.Comment: 24 pages, 7 figures; several additions, published versio

Gastric emptying is slow in chronic fatigue syndrome

BACKGROUND: Gastrointestinal symptoms are common in patients with Chronic Fatigue Syndrome (CFS). The objective of this study was to determine the frequency of these symptoms and explore their relationship with objective (radionuclide) studies of upper GI function. METHODS: Thirty-two (32) patients with CFS and 45 control subjects completed a questionnaire on upper GI symptoms, and the 32 patients underwent oesophageal clearance, and simultaneous liquid and solid gastric emptying studies using radionuclide techniques compared with historical controls. RESULTS: The questionnaires showed a significant difference in gastric (p > 0.01) symptoms and swallowing difficulty. Nocturnal diarrhoea was a significant symptom not previously reported. 5/32 CFS subjects showed slightly delayed oesophageal clearance, but overall there was no significant difference from the control subjects, nor correlation of oesophageal clearance with symptoms. 23/32 patients showed a delay in liquid gastric emptying, and 12/32 a delay in solid gastric emptying with the delay significantly correlated with the mean symptom score (for each p ≪ 0.001). CONCLUSIONS: GI symptoms in patients with chronic fatigue syndrome are associated with objective changes of upper GI motility

Writing in your own voice: An intervention that reduces plagiarism and common writing problems in students' scientific writing.

In many of our courses, particularly laboratory courses, students are expected to engage in scientific writing. Despite various efforts by other courses and library resources, as instructors we are often faced with the frustration of student plagiarism and related writing problems. Here, we describe a simple Writing in Your Own Voice intervention designed to help students become more aware of different types of plagiarism and writing problems, avoid those problems, and practice writing in their own voice. In this article, we will introduce the types of plagiarism and writing problems commonly encountered in our molecular biology laboratory course, the intervention, and the results of our study. From the evaluation of 365 student reports, we found the intervention resulted in nearly 50% fewer instances of plagiarism and common writing problems. We also observed significantly fewer instances of severe plagiarism (e.g. several sentences copied from an external source). In addition, we find that the effects last for several weeks after the students complete the intervention assignment. This assignment is particularly easy to implement and can be a very useful tool for teaching students how to write in their own voices. © 2019 International Union of Biochemistry and Molecular Biology, 47(5):589-598, 2019

The Cepheid Period-Luminosity Relation at Mid-Infrared Wavelengths: I. First-Epoch LMC Data

We present the first mid-infrared Period-Luminosity (PL) relations for Large Magellanic Cloud (LMC) Cepheids. Single-epoch observations of 70 Cepheids were extracted from Spitzer IRAC observations at 3.6, 4.5, 5.8 and 8.0 microns, serendipitously obtained during the SAGE (Surveying the Agents of a Galaxy's Evolution) imaging survey of the LMC. All four mid-infrared PL relations have nearly identical slopes over the period range 6 - 88 days, with a small scatter of only +/-0.16 mag independent of period for all four of these wavelengths. We emphasize that differential reddening is not contributing significantly to the observed scatter, given the nearly two orders of magnitude reduced sensitivity of the mid-IR to extinction compared to the optical. Future observations, filling in the light curves for these Cepheids, should noticeably reduce the residual scatter. These attributes alone suggest that mid-infrared PL relations will provide a practical means of significantly improving the accuracy of Cepheid distances to nearby galaxies.Comment: 19 pages, 4 figures, 1 table, Accepted for publication in the Astrophysical Journa

Suited for Success? : Suits, Status, and Hybrid Masculinity

This document is the Accepted Manuscript version. The final, definitive version of this paper has been published in Men and Masculinities, March 2017, doi: https://doi.org/10.1177/1097184X17696193, published by SAGE Publishing, All rights reserved.This article analyzes the sartorial biographies of four Canadian men to explore how the suit is understood and embodied in everyday life. Each of these men varied in their subject positions—body shape, ethnicity, age, and gender identity—which allowed us to look at the influence of men’s intersectional identities on their relationship with their suits. The men in our research all understood the suit according to its most common representation in popular culture: a symbol of hegemonic masculinity. While they wore the suit to embody hegemonic masculine configurations of practice—power, status, and rationality—most of these men were simultaneously marginalized by the gender hierarchy. We explain this disjuncture by using the concept of hybrid masculinity and illustrate that changes in the style of hegemonic masculinity leave its substance intact. Our findings expand thinking about hybrid masculinity by revealing the ways subordinated masculinities appropriate and reinforce hegemonic masculinity.Peer reviewe

Quasi-local contribution to the scalar self-force: Geodesic Motion

We consider a scalar charge travelling in a curved background spacetime. We calculate the quasi-local contribution to the scalar self-force experienced by such a particle following a geodesic in a general spacetime. We also show that if we assume a massless field and a vacuum background spacetime, the expression for the self-force simplifies significantly. We consider some specific cases whose gravitational analog are of immediate physical interest for the calculation of radiation reaction corrected orbits of binary black hole systems. These systems are expected to be detectable by the LISA space based gravitational wave observatory. We also investigate how alternate techniques may be employed in some specific cases and use these as a check on our own results.Comment: Final Phys. Rev. D version. 24 pages, revtex4. Minor typos correcte