89 results on '"Geoffrey Greene"'
Search Results
2. Development and validation of the ASKFV-SE tool to measure children's self-efficacy for requesting fruits and vegetables
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Sarah Amin, Sabrina Hafner, Jade McNamara, Joanna Raymond, Kate Balestracci, Amanda Missimer, Jacquelyn Potvin, and Geoffrey Greene
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Children ,Fruits ,Self-efficacy ,Vegetables ,Nutrition. Foods and food supply ,TX341-641 ,Medicine - Abstract
The aim of the present study was to develop the ASKFV-SE tool to measure self-efficacy (SE) towards requesting fruits and vegetables (FV) in the home and school environment with school-age children (grades 4–5) from urban, ethnically diverse, low-income households. Cognitive interviews reduced the tool from eleven items to seven. The 7-item questionnaire was tested with 444 children. The items loaded on two factors: home SE (four items) and school SE (two items) with one item was excluded (
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- 2023
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3. Prevalence and correlates of food insecurity among U.S. college students: a multi-institutional study
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Aseel El Zein, Karla P. Shelnutt, Sarah Colby, Melissa J. Vilaro, Wenjun Zhou, Geoffrey Greene, Melissa D. Olfert, Kristin Riggsbee, Jesse Stabile Morrell, and Anne E. Mathews
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Food insecurity ,Food pantry ,College students ,BMI ,Stress ,Sleep ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background College students may be vulnerable to food insecurity due to limited financial resources, decreased buying power of federal aid, and rising costs of tuition, housing, and food. This study assessed the prevalence of food insecurity and its sociodemographic, health, academic, and food pantry correlates among first-year college students in the United States. Methods A cross-sectional study was conducted among first-year students (n = 855) across eight U.S. universities. Food security status was assessed using the U.S. Department of Agriculture Adult Food Security Survey Module. Cohen’s Perceived Stress Scale, Pittsburgh Sleep Quality Index, and Eating Attitudes Test-26 were used to assess perceived stress, sleep quality, and disordered eating behaviors, respectively. Participants self-reported their grade point average (GPA) and completed questions related to meal plan enrollment and utilization of on-campus food pantries. Results Of participating students, 19% were food-insecure, and an additional 25.3% were at risk of food insecurity. Students who identified as a racial minority, lived off-campus, received a Pell grant, reported a parental education of high school or less, and did not participate in a meal plan were more likely to be food-insecure. Multivariate logistic regression models adjusted for sociodemographic characteristics and meal plan enrollment indicated that food-insecure students had significantly higher odds of poor sleep quality (OR = 2.32, 95% CI: 1.43–3.76), high stress (OR = 4.65, 95% CI: 2.66–8.11), disordered eating behaviors (OR = 2.49, 95% CI: 1.20–4.90), and a GPA
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- 2019
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4. Development and Validation of the Short Healthy Eating Index Survey with a College Population to Assess Dietary Quality and Intake
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Sarah Colby, Wenjun Zhou, Chelsea Allison, Anne E. Mathews, Melissa D. Olfert, Jesse Stabile Morrell, Carol Byrd-Bredbenner, Geoffrey Greene, Onikia Brown, Kendra Kattelmann, and Karla Shelnutt
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the HEI ,survey ,diet quality ,Nutrition. Foods and food supply ,TX341-641 - Abstract
Because diet quality (DQ) is associated with risk of chronic disease and is a common construct assessed in health-related research, validated tools to assess DQ are needed that have low respondent and researcher burden. Thus, content experts develop the Short Healthy Eating Index (sHEI) tool and an associated scoring system. The sHEI scoring system was then refined using a classification and regression tree (CRT) algorithm methodology with an iterative feedback process with expert review and input. The sHEI scoring system was then validated using a concurrent criterion validation process that included the sHEI DQ scores (calculated from responses from 50 participants) being compared to the participants’ Healthy Eating Index scores derived from 24 h recalls. The total HEI score from the CRT algorithm highly correlated with the 24 h recall HEI score (0.79). For individual food group items, the correlation between the CRT algorithm scoring and the 24 h recall data scoring ranged from 0.44 for refined grains to 0.64 for whole fruits. The sHEI appears to be a valid tool for estimating overall dietary quality and individual items (with correlations > 0.49) for fruits, vegetables, dairy, added sugar, sugar from sugar-sweetened beverages, and calcium.
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- 2020
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5. Multilevel Structural Equation Modeling of Students’ Dietary Intentions/Behaviors, BMI, and the Healthfulness of Convenience Stores
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Tanya Horacek, Elif Dede Yildirim, Kendra Kattelmann, Carol Byrd-Bredbenner, Onikia Brown, Sarah Colby, Geoffrey Greene, Sharon Hoerr, Tandalayo Kidd, Mallory Koenings, Jesse Morrell, Melissa D. Olfert, Beatrice Phillips, Karla Shelnutt, and Adrienne White
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young adults ,consumer nutrition food environment ,weight ,fruit/vegetable intake ,college environment ,percentage k-calories from fat ,Nutrition. Foods and food supply ,TX341-641 - Abstract
Background: When dietary behaviors are habitual, intentions are low, and environmental cues, such as the consumer food environment, might guide behavior. How might intentions to eat healthily and ultimately actual dietary behaviors, be influenced by the consumer food environment (including the availability and affordability of healthy foods) in convenience stores? This study will determine pathways between the healthfulness of convenience stores and college students’ dietary intentions/behaviors, and body mass index (BMI). Methods: Through multilevel structural equation modeling, a comparison was made of students’ healthful meal intentions (HMI); intake (fruits/vegetables, %kcal/fat, sugar-sweetened beverages (SSBs) and whole-grains); and measured BMI; as well as the healthfulness of convenience stores (fruits/vegetables availability/quality, healthy food availability/affordability). Data was collected on 1401 students and 41 convenience stores across 13 US college campuses. Results: Controlling for gender, HMI was negatively associated with SSBs (β = −0.859) and %kcal/fat (β = −1.057) and positively with whole-grains (β = 0.186) and fruits/vegetables intake (β = 0.267); %Kcal/fat was positively (β = 0.098) and fruits/vegetables intake (β = −0.055) negatively associated with BMI. Campus level, fruits/vegetables availability were positively associated to HMI (β = 0.214, β = 0.129) and directly/negatively to BMI (β = −2.657, β = −1.124). Conclusions: HMI modifies dietary behaviors, with energy from fat and fruit/vegetable intake the most predictive of weight. Availability of fruit/vegetables in convenience stores make it easier for young adults to eat well.
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- 2018
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6. Supplementary Figures 1 - 8, Tables 1 - 3 from Activating ESR1 Mutations Differentially Affect the Efficacy of ER Antagonists
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Sarat Chandarlapaty, José Baselga, Geoffrey Greene, John A. Katzenellenbogen, Sean Fanning, Zhiqiang Li, Sharmeen Uddin, Teresa S. Martin, Kathryn E. Carlson, Elisa De Stanchina, Wai Lin Wong, Christopher Morrow, Joanne Wilson, Aaron Smith, Anne Marie Mazzola, Anne U. Goeppert, Mandy Lawson, Pedram Razavi, Hazel Weir, and Weiyi Toy
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Supplementary Figures 1 - 8, Tables 1 - 3
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- 2023
7. Supplementary Methods from Activating ESR1 Mutations Differentially Affect the Efficacy of ER Antagonists
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Sarat Chandarlapaty, José Baselga, Geoffrey Greene, John A. Katzenellenbogen, Sean Fanning, Zhiqiang Li, Sharmeen Uddin, Teresa S. Martin, Kathryn E. Carlson, Elisa De Stanchina, Wai Lin Wong, Christopher Morrow, Joanne Wilson, Aaron Smith, Anne Marie Mazzola, Anne U. Goeppert, Mandy Lawson, Pedram Razavi, Hazel Weir, and Weiyi Toy
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Supplementary Methods
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- 2023
8. Unconventional Isoquinoline-Based SERMs Elicit Fulvestrant-Like Transcriptional Programs in ER+ Breast Cancer Cells
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Sean Fanning, Govinda Hancock, Kristen Young, David Hosfield, Carstyn Joiner, Emily Sullivan, Yoldas Yildiz, Muriel Laine, and Geoffrey Greene
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Estrogen receptor alpha (ERα) is a ligand-dependent master transcriptional regulator and key driver of breast cancer pathology. Small molecule hormones and competitive antagonists favor unique ERα conformational ensembles that elicit ligand-specific transcriptional programs in breast cancer and other hormone-responsive tissues. By affecting disparate ligand binding domain structural features, unconventional ligand scaffolds can redirect ERα genomic binding patterns to engage novel therapeutic transcriptional programs. To improve our understanding of these ERα structure-transcriptional relationships, we have developed a series of chemically unconventional antagonists based on the antiestrogens RAD1901 and lasofoxifene. High-resolution x-ray co-crystal structures show that these molecules affect both classical and unique structural motifs within the ERα ligand binding pocket. They show moderately reduced antagonistic potencies on ERα genomic activities but are effective anti-proliferative agents in luminal breast cancer cells. Interestingly, they show SERM-like ERα accumulation in breast cancer cells but lack uterotrophic activities in an endometrial cell line. RNA sequencing shows that the lead molecules mediate transcriptional pathways similar to fulvestrant and other SERDs in these cells. This advance shows that fulvestrant-like genomic activities can be achieved without affecting ERα accumulation in breast cancer cells.
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- 2022
9. Abstract 3439: Evaluating nuclear receptor heterodimerization using live cell proximity assays: Implications for novel therapeutic approaches for hormone driven cancers
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Amira Ishag-Osman, David Hosfield, Rosemary Huggins, and Geoffrey Greene
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Cancer Research ,Oncology - Abstract
Breast and prostate cancer are the leading cancer diagnoses for women and men, respectively, second only to cutaneous cancers. Breast and prostate cancer arise from aberrant estrogen/estrogen receptor (ER) and testosterone/androgen receptor signaling (AR), respectively. These sex hormone receptors are members of the steroid hormone receptor family, which also includes the glucocorticoid receptor (GR), mineralocorticoid receptor (MR), and progesterone receptor (PR). Although these receptors canonically function through homodimerization, recent evidence has suggested that receptor crosstalk can amplify or dampen the actions of heterologous receptors. However, these interactions have not been extensively studied in all possible combinations of steroid hormone receptor crosstalk. In this project, we hypothesize that heterodimerization may amplify or repress the transcriptional response(s) elicited by the various receptor complexes depending upon conditions such as concentration of ligands, type of ligand, physiological states, and the types/functions of promoter regions. To test this hypothesis, we investigated the significance of ligand-induced interactions between different homo- and heterodimer combinations of AR, ARV7, GR, MR, PR, and ERα in HEK293 cells using IncuCyte live-cell imaging and NanoBRET technology. Ultimately, the combination of transfection experiments, live-cell imaging, and NanoBRET assays provided insight into which combination of steroid receptors successfully interact to amplify (or dampen) the HaloTag expression, luminescence intensity at 450nM (i.e., NanoLuc expression), and NanoBRET ratio (i.e., acceptor emission luminescence at 610nM divided by donor emission luminescence at 450nM) in HEK293 cells. Our studies revealed that heterodimerization of ERα-PR, ERα-MR, AR-GR, AR-PR, ARV7-MR, ARV7-PR, and GR-MR produced significant ligand-induced changes in signaling intensity compared to no ligand conditions for each fusion protein construct. Additionally, to demonstrate the value of the NanoBRET method for modelling clinically relevant disease conditions, we assessed the physical interaction of ERα and PR in the context of the ERα Y537S mutation - a mutation associated with endocrine therapy resistance in breast cancer that results in a constitutively active ERα. The results showed that ERα-Y537S mutation increases ERα/PR physical interaction upon PR-B stimulation in a NanoBRET proximity-based assay. Future directions include testing these interactions in breast and prostate cancer cell lines and identifying the receptors’ localization within the cell, the results of which may be of clinical importance. Citation Format: Amira Ishag-Osman, David Hosfield, Rosemary Huggins, Geoffrey Greene. Evaluating nuclear receptor heterodimerization using live cell proximity assays: Implications for novel therapeutic approaches for hormone driven cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3439.
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- 2023
10. INSPECT : a dynamic visual query system for geospatial information exploration.
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Sang-Joon Lee, James K. Hahn, Alfred M. Powell Jr., and Geoffrey Greene
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- 2003
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11. O04 The Impact of COVID-19 on Perceived Barriers and Facilitators to the Healthfulness of Communities With Low-Income
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Elder Varela, Jamie Zeldman, Alison Kuch, Yanli Wang, Mohammad Shushari, Elizabeth L. Hall, Jade McNamara, Jesse Stabile Morrell, Terezie Tolar-Peterson, Onikia Brown, Melissa D. Olfert, Lisa Franzen-Castle, Tandalayo Kidd, Sarah Colby, Kendra Kattelmann, Geoffrey Greene, and Karla P. Shelnutt
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Nutrition and Dietetics ,Medicine (miscellaneous) - Published
- 2022
12. LISTEN: A Tool to Investigate the Use of Sound for the Analysis of Program Behavior.
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David B. Boardman, Geoffrey Greene, Vivek Khandelwal, and Aditya P. Mathur
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- 1995
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13. The Effect of a Family-Based Dietary Intervention on Dietary Fiber Density in Children Aged 6 to 11 Years
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Jennifer Nobles, Jade McNamara, Alison Tovar, Stephanie Marchand, Furong Xu, and Geoffrey Greene
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Gerontology ,Nutrition and Dietetics ,business.industry ,Saturated fat ,Psychological intervention ,Physiology ,Overweight ,medicine.disease ,Micronutrient ,Childhood obesity ,Intervention (counseling) ,Weight management ,medicine ,Dietary fiber ,medicine.symptom ,business - Abstract
Background: Fiber intake has been shown to be higher in normal weight children compared to overweight and obese children. However, the effect of family-based interventions have been inconclusive. Objective: To determine if a family-based weight management intervention, which has been successful at lowering BMI Z-score, has an effect on energy adjusted dietary fiber intake and other markers of dietary quality. Methods: Sixty-six children ages 6-11 and their guardians participated in a 16 week nutrition and physical activity intervention. Guardians and children completed a food frequency questionnaire (FFQ) during the first and last sessions. The FFQ provided information about fiber, macronutrients and micronutrients. Results: Children increased fiber from 8.65±2.00g/1000kcal to 9.48±2.26g/1000kcal (p
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- 2019
14. AB069. SOH22ABS209. The epitranscriptomic landscape in estrogen receptor (ER)-positive breast cancer disease progression
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Stephen Keelan, Mihaela Ola, Sara Charmsaz, Sinead Cocchiglia, Karen Crowley, Siobhan Purcell, Fiona Bane, Aisling Hegarty, Ben Doherty, Katherine Sheehan, Lance Hudson, Nicola Cosgrove, Benjamin Roux, Muriel Laine, Geoffrey Greene, Damir Vareslija, Arnold Hill, and Leonie Young
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General Medicine - Published
- 2022
15. New high-sensitivity searches for neutrons converting into antineutrons and/or sterile neutrons at the HIBEAM/NNBAR experiment at the European Spallation Source
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J. I. Marquez, E. Golubeva, Zurab Berezhiani, B. Z. Kopeliovich, K. Dunne, M. Lindroos, L. Townsend, Takeyasu M. Ito, Agneta Oskarsson, A. Kozela, David Milstead, Samuel Silverstein, D. D. DiJulio, S. Yiu, A. D. Dolgov, Lawrence Heilbronn, P. Fierlinger, A. Tureanu, Christian Bohm, G. Ichikawa, B. Rybolt, E. B. Klinkby, Igor Tkachev, Arkady Vainshtein, Y. N. Pokotilovski, Archil Kobakhidze, Kevin W. Anderson, R. W. Pattie, Y. J. Jwa, Leah Broussard, R. Biondi, B. Kerbikov, David V. Baxter, J. Cedercäll, David Olle Rickard Silvermyr, A. Holley, A. Addazi, A. P. Serebrov, Hans P. Mumm, S. Girmohanta, V. Santoro, Arthur E. Ruggles, P. Geltenbort, Yuri Kamyshkov, H. M. Shimizu, Geoffrey Greene, N. Rizzi, Joshua Barrow, A. Takibayev, Christopher Crawford, T. Greenshaw, N. Rossi, E. Paryev, Thomas Nilsson, A. A. Nepomuceno, Robert Shrock, L. W. Koerner, R. Woracek, T. Johansson, S. Gardiner, L. Varriano, G. Muhrer, Susan Gardner, A. Kupsc, J. M. Richard, Bernhard Meirose, R. Hall-Wilton, Vladimir Gudkov, T. Morishima, J. Makkinje, E. Rinaldi, J. Herrero-Garcia, Michael R. Fitzsimmons, P. S. B. Dev, Y. T. Lee, Erik B. Iverson, K. S. Babu, Y. Yamagata, C. Redding, H. Perrey, Rabindra N. Mohapatra, Albert Young, V. V. Nesvizhevsky, Masaaki Kitaguchi, S. Penttil, G. Brooijmans, Fabrizio Nesti, J. de Vries, Riccardo Bevilacqua, O. Zimmer, Kalliopi Kanaki, Robert Wagner, K. Ramic, E. Kearns, Z. Zhang, K. Nagamoto, L. Zanini, S. Ansell, P. M. Bentley, T. Kittelmann, A. Fomin, T. M. Miller, U. Sarkar, Goran Senjanovic, A. Galindo-Uribarri, W. M. Snow, Pavel Golubev, V. A. Kudryavtsev, M. J. Frost, Z. Kokai, A. Saunders, L. Jönsson, D. Ries, I. Potashnikovav, Institut Laue-Langevin (ILL), ILL, Institut de Physique des 2 Infinis de Lyon (IP2I Lyon), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), and Department of Physics
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baryon number violation ,feebly interacting particles ,European Spallation Source ,baryogenesis ,Physics beyond the Standard Model ,Nuclear Theory ,EXPERIMENTAL LIMIT ,Antineutron ,01 natural sciences ,Subatomär fysik ,ANTIPROTON ANNIHILATION ,n: oscillation ,Subatomic Physics ,[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex] ,Nuclear Experiment ,sterile ,Physics ,MIRROR MATTER ,new physics ,anti-n ,ddc ,Antimatter ,baryon: asymmetry ,proposed experiment ,DAMA ANNUAL MODULATION ,Nuclear and High Energy Physics ,Particle physics ,Accelerator Physics and Instrumentation ,114 Physical sciences ,Baryon asymmetry ,nuclear physics ,0103 physical sciences ,DARK-MATTER ,mixing ,Neutron ,Sensitivity (control systems) ,[PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det] ,TRANSITION OPERATORS ,010306 general physics ,baryon number: violation ,activity report ,010308 nuclear & particles physics ,High Energy Physics::Phenomenology ,Acceleratorfysik och instrumentering ,MAJORANA NEUTRINOS ,sensitivity ,Baryogenesis ,regeneration ,UNIFIED PICTURE ,B-L SYMMETRY ,Baryon number ,BARYON-NUMBER NONCONSERVATION - Abstract
The violation of baryon number, B , is an essential ingredient for the preferential creation of matter over antimatter needed to account for the observed baryon asymmetry in the Universe. However, such a process has yet to be experimentally observed. The HIBEAM/NNBAR program is a proposed two-stage experiment at the European Spallation Source to search for baryon number violation. The program will include high-sensitivity searches for processes that violate baryon number by one or two units: free neutron–antineutron oscillation ( n → n ̄ ) via mixing, neutron–antineutron oscillation via regeneration from a sterile neutron state ( n → [ n ′ , n ̄ ′ ] → n ̄ ), and neutron disappearance (n → n′); the effective Δ B = 0 process of neutron regeneration ( n → [ n ′ , n ̄ ′ ] → n ) is also possible. The program can be used to discover and characterize mixing in the neutron, antineutron and sterile neutron sectors. The experiment addresses topical open questions such as the origins of baryogenesis and the nature of dark matter, and is sensitive to scales of new physics substantially in excess of those available at colliders. A goal of the program is to open a discovery window to neutron conversion probabilities (sensitivities) by up to three orders of magnitude compared with previous searches. The opportunity to make such a leap in sensitivity tests should not be squandered. The experiment pulls together a diverse international team of physicists from the particle (collider and low energy) and nuclear physics communities, while also including specialists in neutronics and magnetics.
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- 2021
16. Imaging Fluorescence of He2* Excimers Created by Neutron Capture in Liquid Helium II
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Lowell Crow, Ryan S. Glasby, Anthony Mezzacappa, Michael R. Fitzsimmons, S. R. Bao, L. McDonald, Geoffrey Greene, Wei Guo, J. Pierce, X. Wen, and Xin Tong
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Materials science ,Liquid helium ,Turbulence ,General Physics and Astronomy ,01 natural sciences ,Fluorescence ,Ionizing radiation ,law.invention ,Vortex ,Viscosity ,Neutron capture ,law ,0103 physical sciences ,Atomic physics ,010306 general physics ,Laser beams - Abstract
We show unequivocal evidence for formation of He_{2}^{*} excimers in liquid He II created by ionizing radiation produced through neutron capture. Laser beams induce fluorescence of the excimers. The fluorescence is recorded at a rate of 55.6 Hz by a camera. The location of the fluorescence is determined with an uncertainty of 5 μm. The technique provides an opportunity to record the flow of He_{2}^{*} excimers in a medium with very small viscosity and enables measurement of turbulence around macroscopic liter size objects or vortex matter in three dimensions.
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- 2020
17. Monte Carlo calculation and verification of the geometrical factors for the NPDGamma experiment
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D. Blyth, Matthew Musgrave, Kyle B. Grammer, Nadia Fomin, Zhaowen Tang, Geoffrey Greene, Elise Tang, and J. D. Bowman
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Physics ,Nuclear and High Energy Physics ,Physics - Instrumentation and Detectors ,010308 nuclear & particles physics ,media_common.quotation_subject ,Astrophysics::High Energy Astrophysical Phenomena ,Monte Carlo method ,Detector ,FOS: Physical sciences ,Parity (physics) ,Instrumentation and Detectors (physics.ins-det) ,Spin isomers of hydrogen ,01 natural sciences ,Asymmetry ,Computational physics ,Neutron capture ,Sine wave ,0103 physical sciences ,Neutron ,High Energy Physics::Experiment ,010306 general physics ,Nuclear Experiment ,Instrumentation ,media_common - Abstract
The NPDGamma experiment measures the parity-violating asymmetry in $\gamma$-ray emission in the capture of polarized neutrons on liquid parahydrogen. The sensitivity to the asymmetry for each detector in the array is used as a parameter in the extraction of the physics asymmetry from the measured data. The detector array is approximately cylindrically symmetric around the target and a step-wise sinusoidal function has been used for the sensitivity in the previous iteration of the NPDGamma experiment, but deviations from cylindrical symmetry necessitate the use of a Monte Carlo model to determine corrections to the geometrical factors. For the calculations, source code modifications to MCNPX were done in order to calculate the sensitivity of each cesium iodide detector to the physics asymmetry. We describe the MCNPX model and results from calculations and how the results are validated through measurement of the parity violating asymmetry of $\gamma$-rays from neutron capture on chlorine., Comment: 10 pages, 10 figures
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- 2019
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18. Precision neutron flux measurement using the Alpha-Gamma device
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Geoffrey Greene, Hans P. Mumm, Nadia Fomin, W. M. Snow, Evan R. Adamek, Jeffrey S. Nico, Shannon Fogwell Hoogerheide, David M. Gilliam, and Maynard S. Dewey
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Physics ,010308 nuclear & particles physics ,Astrophysics::High Energy Astrophysical Phenomena ,QC1-999 ,chemistry.chemical_element ,Germanium ,Neutron radiation ,01 natural sciences ,Nuclear physics ,Cross section (physics) ,Neutron capture ,chemistry ,Neutron flux ,0103 physical sciences ,NIST ,Neutron ,010306 general physics ,Boron ,Nuclear Experiment - Abstract
The Alpha-Gamma device at the National Institute of Standards and Technology (NIST) utilizes neutron capture on a totally absorbing 10B deposit to measure the absolute neutron flux of a monochromatic cold neutron beam. Gammas produced by the boron capture are counted using high purity germanium detectors, which are calibrated using a well-measured 239Pu alpha source and the alpha-to-gamma ratio from neutron capture on a thin 10B target. This device has been successfully operated and used to calibrate the neutron flux monitor for the BL2 neutron lifetime experiment at NIST. It is also being used for a measurement of the 6Li(n,t)4He cross section. We shall present its principle of operation along with the current and planned projects involving the Alpha-Gamma device, including the recalibration of the U.S. national neutron standard NBS-1 and (n,f) cross section measurements of 235U.
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- 2019
19. First Observation of P -odd γ Asymmetry in Polarized Neutron Capture on Hydrogen
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J. R. Calarco, C. Hayes, Dinko Pocanic, J. Hall, Charles Fieseler, V. Cianciolo, Xin Tong, S. Baeßler, S. Schröder, A. Ramírez-Morales, S. Santra, R. Whitehead, K. Craycraft, Kyle B. Grammer, E. Askanazi, P. N. Seo, S. Balascuta, Erik B. Iverson, A. Sprow, R. Mahurin, Ivan Novikov, J. Stewart, M. Musgrave, E. Frlež, N. Birge, Nadia Fomin, L. Alonzi, A. Salas-Bacci, I. Garishvili, W. M. Snow, Bernhard Lauss, S. Kucuker, W. S. Wilburn, M. Root, Timothy Chupp, D. Evans, Geoffrey Greene, Yasuhiro Masuda, Ricardo Alarcon, F. Simmons, H. Nann, M. Maldonado-Velázquez, M. L. Kabir, E. M. Scott, Robert Milburn, R. C. Gillis, J. D. Bowman, C. E. Coppola, M. McCrea, E. Tang, E. I. Sharapov, Michael Gericke, J. Fry, Christopher Crawford, S. I. Penttilä, D. Blyth, J. Hamblen, P. E. Mueller, Alexander Barzilov, L. Barrón-Palos, Z. Tang, J. Mei, D. Parsons, and D. J. Turkoglu
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Coupling constant ,Physics ,Meson ,010308 nuclear & particles physics ,media_common.quotation_subject ,General Physics and Astronomy ,Spin isomers of hydrogen ,Coupling (probability) ,01 natural sciences ,Asymmetry ,Pion ,0103 physical sciences ,Effective field theory ,Neutron ,Atomic physics ,010306 general physics ,media_common - Abstract
We report the first observation of the parity-violating gamma-ray asymmetry A_{γ}^{np} in neutron-proton capture using polarized cold neutrons incident on a liquid parahydrogen target at the Spallation Neutron Source at Oak Ridge National Laboratory. A_{γ}^{np} isolates the ΔI=1, ^{3}S_{1}→^{3}P_{1} component of the weak nucleon-nucleon interaction, which is dominated by pion exchange and can be directly related to a single coupling constant in either the DDH meson exchange model or pionless effective field theory. We measured A_{γ}^{np}=[-3.0±1.4(stat)±0.2(syst)]×10^{-8}, which implies a DDH weak πNN coupling of h_{π}^{1}=[2.6±1.2(stat)±0.2(syst)]×10^{-7} and a pionless EFT constant of C^{^{3}S_{1}→^{3}P_{1}}/C_{0}=[-7.4±3.5(stat)±0.5(syst)]×10^{-11} MeV^{-1}. We describe the experiment, data analysis, systematic uncertainties, and implications of the result.
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- 2018
20. Neutron-antineutron oscillations: Theoretical status and experimental prospects
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Yuri Kamyshkov, Ayman I. Hawari, Amit Roy, Lawrence W. Townsend, T. Gabriel, Chris Quigg, Robert W. Pattie, Hans P. Mumm, A. Serebrov, P. L. McGaughey, L. Okun, Masaaki Kitaguchi, G. Brooijmans, Lawrence Heilbronn, S. Striganov, B. Z. Kopeliovich, R. Van Kooten, Zurab Berezhiani, Mingshui Chen, Franz X. Gallmeier, K. S. Ganezer, Calvin A. Johnson, Luis A. Castellanos, M. Bergevin, N.V. Mokhov, Ramanath Cowsik, B. Hartfiel, Saptaparna Bhattacharya, E. B. Dees, Arkady Vainshtein, Rabindra N. Mohapatra, Albert Young, Avraham Gal, R. Tschirhart, Michael Mocko, Utpal Sarkar, M. Frost, Geoffrey Greene, V. B. Kopeliovich, Alexander Saunders, E. J. Ramberg, Zhehui Wang, G. Muhrer, S. K. L. Sjue, Arthur E. Ruggles, Prasanta Kumar Das, D. G. Phillips, A. Ray, A. K. Sikdar, K. S. Babu, H. M. Shimizu, V. A. Kuzmin, William Snow, J. A. Crabtree, B. Kerbikov, E. Golubeva, A. D. Dolgov, Chen-Yu Liu, David V. Baxter, C. E. Coppola, Robert Shrock, Phillip D. Ferguson, and Sw. Banerjee
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Cold neutron source ,Quasi-free condition ,Physics - Instrumentation and Detectors ,Nuclear Theory ,Proton decay ,media_common.quotation_subject ,General Physics and Astronomy ,FOS: Physical sciences ,Physics and Astronomy(all) ,Antineutron ,01 natural sciences ,High Energy Physics - Experiment ,Nuclear physics ,Nuclear Theory (nucl-th) ,High Energy Physics - Experiment (hep-ex) ,Baryon asymmetry ,High Energy Physics - Phenomenology (hep-ph) ,0103 physical sciences ,Baryon number violation ,Spallation ,Neutron ,Nuclear Experiment (nucl-ex) ,Nuclear Experiment ,010306 general physics ,media_common ,Physics ,Annihilation ,010308 nuclear & particles physics ,Instrumentation and Detectors (physics.ins-det) ,Neutron radiation ,Universe ,High Energy Physics - Phenomenology ,Neutrino - Abstract
This paper summarizes the relevant theoretical developments, outlines some ideas to improve experimental searches for free neutron-antineutron oscillations, and suggests avenues for future improvement in the experimental sensitivity., Comment: Submitted to Physics Reports
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- 2016
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21. A new cryogenic apparatus to search for the neutron electric dipole moment
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R. J. Holt, Seppo Penttila, S. Baessler, David G. Haase, C. R. Gould, M. E. Hayden, Dipangkar Dutta, S. W. T. MacDonald, L. Barrón-Palos, E. Korobkina, R. P. Redwine, Jen-Chieh Peng, Marcus H. Mendenhall, J. Long, Z. Tang, Haiyan Gao, Steven Clayton, Ross Milner, Evgeni Tsentalovich, J. Kelsey, Robert Golub, E. Ihloff, C. Vidal, S. E. Williamson, Matthew Busch, A. T. Holley, George M. Seidel, A. Saftah, M. Behzadipour, B. W. Filippone, M. Makela, Ayman I. Hawari, I. Berkutov, C. Osthelder, C. Daurer, Ricardo Alarcon, W. Yao, A. Reid, M. Broering, C. Swank, P. R. Huffman, S. Slutsky, Musa Ahmed, J. Leggett, Liang Yang, John Ramsey, Yu. Efremenko, H. O. Meyer, M. Blatnik, R. Carr, James Maxwell, T. D. S. Stanislaus, Scott Currie, E. S. Smith, W. M. Snow, A. Lipman, Takeyasu M. Ito, N. S. Phan, A. Aleksandrova, Leah Broussard, C.-Y. Liu, X. Sun, Steve K. Lamoreaux, K. A. Dow, Nima Nouri, D. P. Kendellen, A. Matlashov, R. Dipert, L. M. Bartoszek, K. K. H. Leung, C. O'Shaughnessy, M. Karcz, C. B. Erickson, Yongsun Kim, Wanchun Wei, A. R. Young, S. K. Imam, J. Bessuille, Geoffrey Greene, R. Tavakoli Dinani, T. M. Rao, S. Sosothikul, Douglas H Beck, D. Hasell, Wolfgang Korsch, P. E. Mueller, I.F. Silvera, C. R. White, M. D. Cooper, Christopher Crawford, Nadia Fomin, W. E. Sondheim, Brad Plaster, and V. Cianciolo
- Subjects
Physics ,Physics - Instrumentation and Detectors ,Neutron electric dipole moment ,010308 nuclear & particles physics ,FOS: Physical sciences ,Instrumentation and Detectors (physics.ins-det) ,Oak Ridge National Laboratory ,01 natural sciences ,030218 nuclear medicine & medical imaging ,Superfluidity ,Nuclear physics ,03 medical and health sciences ,0302 clinical medicine ,Electric field ,0103 physical sciences ,Limit (music) ,Neutron ,Sensitivity (control systems) ,Nuclear Experiment (nucl-ex) ,Nuclear Experiment ,Instrumentation ,Mathematical Physics ,Spallation Neutron Source - Abstract
© 2019 IOP Publishing Ltd and Sissa Medialab. A cryogenic apparatus is described that enables a new experiment, nEDM@SNS, with a major improvement in sensitivity compared to the existing limit in the search for a neutron Electric Dipole Moment (EDM). This apparatus uses superfluid 4He to produce a high density of Ultra-Cold Neutrons (UCN) which are contained in a suitably coated pair of measurement cells. The experiment, to be operated at the Spallation Neutron Source at Oak Ridge National Laboratory, uses polarized 3He from an Atomic Beam Source injected into the superfluid 4He and transported to the measurement cells where it serves as a co-magnetometer. The superfluid 4He is also used as an insulating medium allowing significantly higher electric fields, compared to previous experiments, to be maintained across the measurement cells. These features provide an ultimate statistical uncertainty for the EDM of 2-3× 10-28 e-cm, with anticipated systematic uncertainties below this level.
- Published
- 2019
22. Measurement of the absolute neutron beam polarization from a supermirror polarizer and the absolute efficiency of a neutron spin rotator for the NPDGamma experiment using a polarized $^{3}$He neutron spin-filter
- Author
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S. Balascuta, P. R. Huffman, P. E. Mueller, M.M. Musgrave, D. Blyth, W. M. Snow, V. Cianciolo, Nadia Fomin, Geoffrey Greene, J. D. Bowman, Christopher Crawford, C. Hayes, M. McCrea, E. Tang, J. Hamblen, L. Barrón-Palos, K. Craycraft, Zhaowen Tang, Kyle B. Grammer, S. Kucuker, W. S. Wilburn, Chenyang Jiang, Xin Tong, S. Baeßler, R. C. Gillis, Seppo Penttila, Timothy Chupp, Michael Gericke, and J. Fry
- Subjects
Nuclear and High Energy Physics ,Physics - Instrumentation and Detectors ,Astrophysics::High Energy Astrophysical Phenomena ,Nuclear Theory ,FOS: Physical sciences ,01 natural sciences ,law.invention ,Nuclear physics ,law ,0103 physical sciences ,Neutron ,Nuclear Experiment (nucl-ex) ,010306 general physics ,Nuclear Experiment ,Instrumentation ,Physics ,010308 nuclear & particles physics ,Instrumentation and Detectors (physics.ins-det) ,Polarizer ,Neutron radiation ,3. Good health ,Neutron capture ,Beamline ,Neutron source ,Physics::Accelerator Physics ,Spallation Neutron Source ,Beam (structure) - Abstract
Accurately measuring the neutron beam polarization of a high flux, large area neutron beam is necessary for many neutron physics experiments. The Fundamental Neutron Physics Beamline (FnPB) at the Spallation Neutron Source (SNS) is a pulsed neutron beam that was polarized with a supermirror polarizer for the NPDGamma experiment. The polarized neutron beam had a flux of $\sim10^9$ neutrons per second per cm$^2$ and a cross sectional area of 10$\times$12~cm$^2$. The polarization of this neutron beam and the efficiency of a RF neutron spin rotator installed downstream on this beam were measured by neutron transmission through a polarized $^{3}$He neutron spin-filter. The pulsed nature of the SNS enabled us to employ an absolute measurement technique for both quantities which does not depend on accurate knowledge of the phase space of the neutron beam or the $^{3}$He polarization in the spin filter and is therefore of interest for any experiments on slow neutron beams from pulsed neutron sources which require knowledge of the absolute value of the neutron polarization. The polarization and spin-reversal efficiency measured in this work were done for the NPDGamma experiment, which measures the parity violating $\gamma$-ray angular distribution asymmetry with respect to the neutron spin direction in the capture of polarized neutrons on protons. The experimental technique, results, systematic effects, and applications to neutron capture targets are discussed., Comment: 13 pages, 14 figures, 2 tables
- Published
- 2018
23. What Do We Know About Resilience in Older Adults? An Exploration of Some Facts, Factors, and Facets
- Author
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Phillip G. Clark, Patricia M. Burbank, Geoffrey Greene, and Deborah Riebe
- Subjects
0301 basic medicine ,03 medical and health sciences ,030109 nutrition & dietetics ,0302 clinical medicine ,030212 general & internal medicine - Published
- 2018
24. Fundamental neutron physics beamline at the spallation neutron source at ORNL
- Author
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P. R. Huffman, Erik B. Iverson, T.M. Tito, R.R. Allen, V. Cianciolo, Christopher Crawford, W. M. Snow, R. Mahurin, Nadia Fomin, and Geoffrey Greene
- Subjects
Accelerator Physics (physics.acc-ph) ,Physics ,Nuclear and High Energy Physics ,Physics - Instrumentation and Detectors ,Astrophysics::High Energy Astrophysical Phenomena ,Nuclear Theory ,FOS: Physical sciences ,Instrumentation and Detectors (physics.ins-det) ,Oak Ridge National Laboratory ,Neutron scattering ,Cosmology ,3. Good health ,Nuclear physics ,Beamline ,Physics::Accelerator Physics ,Neutron detection ,Physics - Accelerator Physics ,Spallation ,Nuclear Experiment (nucl-ex) ,Nuclear Experiment ,Instrumentation ,Spallation Neutron Source ,Beam (structure) - Abstract
We describe the Fundamental Neutron Physics Beamline (FnPB) facility located at the Spallation Neutron Source at Oak Ridge National Laboratory. The FnPB was designed for the conduct of experiments that investigate scientific issues in nuclear physics, particle physics, astrophysics and cosmology using a pulsed slow neutron beam. We present a detailed description of the design philosophy, beamline components, and measured fluxes of the polychromatic and monochromatic beams.
- Published
- 2015
25. Considerations for an Intense Source of Ultracold Neutrons at the European Long Pulse Spallation Source
- Author
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Geoffrey Greene and J. M. Pendlebury
- Subjects
Nuclear physics ,Superfluidity ,Physics ,Ultra-cold neutron sources ,Long pulse ,UCN sources at long pulse spallation sources ,Ultracold neutrons ,Spallation ,Neutron ,UCN sources at reactors ,Physics and Astronomy(all) - Abstract
While intense reactor based sources of ultra-cold neutrons have been in operation for approximately three decades, it is only in the last few years that practical sources of UCN have been realized at spallation sources. Existing and proposed spallation based UCN sources employ two distinct strategies. In the first, the UCN converter (superfluid 4He, or solid D2) is placed in the immediate vicinity of the spallation target. In the second, a converter (usually superfluid He) is placed at the output end of a cold neutron guide fed by the spallation target cold source. Both of these approaches are considered in relation to the European Long Pulse Spallation Source.
- Published
- 2014
26. Status of the NPDGamma experiment
- Author
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C. Garcia, E. Frlež, E. Askanazi, S. Balascuta, Dinko Pocanic, D. Evans, P. N. Seo, H. Nann, Kyle B. Grammer, M. Musgrave, Gregory S. Mitchell, Bernhard Lauss, R. Mahurin, D. Blyth, F. Simmons, Geoffrey Greene, V.W. Yuan, E. Tang, L. Kabir, S. A. Page, J. R. Calarco, Ricardo Alarcon, C. Hayes, Timothy Chupp, Yi-De Zhang, T. Tong, Erik B. Iverson, C. E. Coppola, L. Barrón-Palos, Alexander Barzilov, W. Fox, Charles Fieseler, I. Garishvili, K. Craycraft, J. Stuart, F. W. Hersman, Y. Li, Z. Tang, M. Sharma, R. Allen, Christopher Crawford, J. Vanderwerp, Gordon L. Jones, P. E. Mueller, J. Hamblen, Yasuhiro Masuda, S. I. Penttilä, Robert Milburn, S. Baeßler, A. Salas-Bacci, C. Fu, D. Parsons, Ivan Novikov, E. I. Sharapov, Takashi Ino, Nadia Fomin, S. Kucucker, Stuart J. Freedman, J. Thomison, W. D. Ramsay, Michael Gericke, C. Blessinger, M. Maldonado-Velázquez, J. Fry, M. Dabaghyan, R. C. Gillis, M. McCrea, S. Waldecker, J. Mei, T. B. Smith, J. D. Bowman, S. Santra, Suguru Muto, W. M. Snow, W. Xu, W. S. Wilburn, and J. Favela
- Subjects
Nuclear and High Energy Physics ,Particle physics ,Meson ,media_common.quotation_subject ,Nuclear Theory ,Hadron ,Weak interaction ,01 natural sciences ,7. Clean energy ,Asymmetry ,Nuclear physics ,0103 physical sciences ,Neutron ,Physical and Theoretical Chemistry ,Nuclear Experiment ,010306 general physics ,media_common ,Physics ,010308 nuclear & particles physics ,Condensed Matter Physics ,Atomic and Molecular Physics, and Optics ,Neutron capture ,Physics::Accelerator Physics ,High Energy Physics::Experiment ,Nucleon ,Spallation Neutron Source - Abstract
The NPDGamma experiment measures the parity-violating (PV) gamma asymmetry from polarized cold neutrons captured on protons at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL). The (PV) neutron spin asymmetry A γ of photons from polarized cold neutron capture on protons is proportional to the ΔI=1 long range weak meson coupling $h_{\pi }^{1}$ between nucleons in the hadronic weak interaction (HWI). Liquid para-hydrogen production data taking concluded in April 2014 and once the background aluminum asymmetry measurements are complete, the PV asymmetry A γ can be extracted. Preliminary results of the analysis of A γ are presented.
- Published
- 2016
27. Development of an Instrument Measuring Perceived Environmental Healthfulness: Behavior Environment Perception Survey (BEPS)
- Author
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Jade McNamara, Melissa D. Olfert, Morgan Sowers, Sarah Colby, Adrienne White, Carol Byrd-Bredbenner, Kendra Kattelmann, Lisa Franzen-Castle, Onikia Brown, Tandalayo Kidd, Karla Shelnutt, and Geoffrey Greene
- Subjects
Nutrition and Dietetics ,Medicine (miscellaneous) - Published
- 2018
28. The neutron electric dipole moment experiment at the Spallation Neutron Source
- Author
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Scott Currie, John Ramsey, Haiyan Gao, Dipangkar Dutta, Jen-Chieh Peng, Y.J. Kim, A. Lipman, A. Matlashov, E. Ihloff, M. Blatnik, E. Korobkina, M. McCrea, P. R. Huffman, C. R. Gould, C. M. O'Shaughnessy, Brad Plaster, D. Hasell, T. Rao, Mark Makela, T. D. S. Stanislaus, Wanchun Wei, C. B. Erickson, S. Baeßler, Nima Nouri, M. E. Hayden, Liang Yang, M. Broering, Ayman I. Hawari, S. Sosothikul, Yu. Efremenko, S. E. Williamson, P. E. Mueller, L. M. Bartoszek, K. K. H. Leung, A. R. Young, L. Barrón-Palos, Seppo Penttila, J. Bessuille, Geoffrey Greene, Steve K. Lamoreaux, K. A. Dow, S. W. T. MacDonald, Leah Broussard, Douglas H Beck, M. Behzadipour, Ricardo Alarcon, W. Yao, S. Slutsky, Christopher Crawford, A. Aleksandrova, R. Tavakoli Dinani, David G. Haase, Evgeni Tsentalovich, R. J. Holt, Z. Tang, R. P. Redwine, J. Kelsey, Matthew Busch, E. Leggett, A. Saftah, Steven Clayton, Ross Milner, M. W. Ahmed, Nadia Fomin, C. Vidal, Wolfgang Korsch, V. Cianciolo, E. Smith, I.F. Silvera, C. R. White, Marcus H. Mendenhall, J. Long, R. Dipert, Robert Golub, A. T. Holley, C. Osthelder, R. Carr, W. M. Snow, George M. Seidel, B. W. Filippone, W. E. Sondheim, Takeyasu M. Ito, N. S. Phan, C. Daurer, M. D. Cooper, A. Reid, C. Swank, James Maxwell, X. Sun, Pinghan Chu, H. O. Meyer, and C.-Y. Liu
- Subjects
Physics ,Physics - Instrumentation and Detectors ,Neutron electric dipole moment ,010308 nuclear & particles physics ,QC1-999 ,FOS: Physical sciences ,Field strength ,Instrumentation and Detectors (physics.ins-det) ,7. Clean energy ,01 natural sciences ,Nuclear physics ,Electric field ,0103 physical sciences ,Electromagnetic shielding ,Precession ,Ultracold neutrons ,Nuclear Experiment (nucl-ex) ,010306 general physics ,Spin (physics) ,Nuclear Experiment ,Spallation Neutron Source - Abstract
Novel experimental techniques are required to make the next big leap in neutron electric dipole moment experimental sensitivity, both in terms of statistics and systematic error control. The nEDM experiment at the Spallation Neutron Source (nEDM@SNS) will implement the scheme of Golub & Lamoreaux [Phys. Rep., 237, 1 (1994)]. The unique properties of combining polarized ultracold neutrons, polarized $^3$He, and superfluid $^4$He will be exploited to provide a sensitivity to $\sim 10^{-28}\,e{\rm \,\cdot\, cm}$. Our cryogenic apparatus will deploy two small ($3\,{\rm L}$) measurement cells with a high density of ultracold neutrons produced and spin analyzed in situ. The electric field strength, precession time, magnetic shielding, and detected UCN number will all be enhanced compared to previous room temperature Ramsey measurements. Our $^3$He co-magnetometer offers unique control of systematic effects, in particular the Bloch-Siegert induced false EDM. Furthermore, there will be two distinct measurement modes: free precession and dressed spin. This will provide an important self-check of our results. Following five years of "critical component demonstration," our collaboration transitioned to a "large scale integration" phase in 2018. An overview of our measurement techniques, experimental design, and brief updates are described in these proceedings., Submitted to proceedings of PPNS 2018 - International Workshop on Particle physics at Neutron Sources (https://www.webofconferences.org/epj-web-of-conferences-forthcoming-conferences/1148-ppns-2018)
- Published
- 2019
29. Progress on the BL2 beam measurement of the neutron lifetime
- Author
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C. DeAngelis, Bret E. Crawford, W. M. Snow, Sai Meghasena Chavali, Maynard S. Dewey, Nadia Fomin, David M. Gilliam, Fangchen Li, Daniel Valete, Kyle B. Grammer, Ripan Biswas, Evan R. Adamek, Jonathan Mulholland, Jimmy Caylor, Geoffrey Greene, Juliet A. Ivanov, Shannon Fogwell Hoogerheide, Fred E. Wietfeldt, H. Pieter Mumm, Eamon S. Anderson, A. Yue, Jeffrey S. Nico, and Robert Haun
- Subjects
Physics ,Proton ,Astrophysics::High Energy Astrophysical Phenomena ,QC1-999 ,Computer Science::Information Retrieval ,Nuclear Theory ,Neutron radiation ,Standard Model ,Nuclear physics ,Big Bang nucleosynthesis ,Neutron ,Matrix element ,Nuclear Experiment ,Beam (structure) - Abstract
A precise value of the neutron lifetime is important in several areas of physics, including determinations of the quark-mixing matrix element |Vud|, related tests of the Standard Model, and predictions of light element abundances in Big Bang Nucleosynthesis models. We report the progress on a new measurement of the neutron lifetime utilizing the cold neutron beam technique. Several experimental improvements in both neutron and proton counting that have been developed over the last decade are presented. This new effort should yield a final uncertainty on the lifetime of 1 s with an improved understanding of the systematic effects.
- Published
- 2019
30. The Nab experiment: A precision measurement of unpolarized neutron beta decay
- Author
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Timothy Chupp, S. Samiei, C. Hendrus, E. Frlež, D. van Petten, P. E. Mueller, K. P. Rykaczewski, J. Wexler, N. Macsai, B. A. Zeck, W. Farrar, A. T. Bryant, Leah Broussard, T. Bailey, Robert Grzywacz, R. Mammei, S. Balascuta, M. Doyle, T. Shelton, R. Picker, Christopher Crawford, Wenjiang Fan, Seppo Penttila, C. Hayes, E. Smith, M. McCrea, W. S. Wilburn, K. Bass, D. Borissenko, J. Pierce, G. Randall, Juliette Mammei, Ricardo Alarcon, R. Whitehead, A. Smith, K. Chang, Sky Sjue, Michael Gericke, C. D. McLaughlin, G. Riley, P. L. McGaughey, J. D. Bowman, J. Caylor, Mark Makela, Vladimir Gudkov, Nadia Fomin, E. M. Scott, A. Salas-Bacci, M. Martinez, J. Byrne, T. V. Cianciolo, J. Fry, J.R. Calarco, L. Barrón Palos, Dinko Pocanic, F. Glück, D. E. Perryman, Geoffrey Greene, A. P. Jezghani, M. Gervais, A. Blose, D.G. Matthews, Y. Qian, Hui Li, N. Birge, Eric Stevens, X. Ding, Takeyasu M. Ito, J. Ramsey, J. Hamblen, Albert Young, and S. Baeßler
- Subjects
Physics ,Proton ,Spectrometer ,010308 nuclear & particles physics ,QC1-999 ,Nuclear Theory ,FOS: Physical sciences ,Electron ,Weak interaction ,01 natural sciences ,Beta decay ,Nuclear physics ,Time of flight ,0103 physical sciences ,Neutron ,Nuclear Experiment (nucl-ex) ,Nuclear Experiment ,010306 general physics ,Spallation Neutron Source - Abstract
Neutron beta decay is one of the most fundamental processes in nuclear physics and provides sensitive means to uncover the details of the weak interaction. Neutron beta decay can evaluate the ratio of axial-vector to vector coupling constants in the standard model, $\lambda = g_A / g_V$, through multiple decay correlations. The Nab experiment will carry out measurements of the electron-neutrino correlation parameter $a$ with a precision of $\delta a / a = 10^{-3}$ and the Fierz interference term $b$ to $\delta b = 3\times10^{-3}$ in unpolarized free neutron beta decay. These results, along with a more precise measurement of the neutron lifetime, aim to deliver an independent determination of the ratio $\lambda$ with a precision of $\delta \lambda / \lambda = 0.03\%$ that will allow an evaluation of $V_{ud}$ and sensitively test CKM unitarity, independent of nuclear models. Nab utilizes a novel, long asymmetric spectrometer that guides the decay electron and proton to two large area silicon detectors in order to precisely determine the electron energy and an estimation of the proton momentum from the proton time of flight. The Nab spectrometer is being commissioned at the Fundamental Neutron Physics Beamline at the Spallation Neutron Source at Oak Ridge National Lab. We present an overview of the Nab experiment and recent updates on the spectrometer, analysis, and systematic effects., Comment: Presented at PPNS2018
- Published
- 2019
31. The implementation of a super mirror polarizer at the SNS fundamental neutron physics beamline
- Author
-
Robert Milburn, S. Balascuta, S. Baeβler, S. I. Penttilä, Christopher Crawford, J. Prince, Ricardo Alarcon, Geoffrey Greene, J. Schädler, and Alexander Mietke
- Subjects
Physics ,Nuclear and High Energy Physics ,business.industry ,Polarizer ,Neutron radiation ,Polarization (waves) ,Magnetic field ,law.invention ,Neutron capture ,Optics ,Beamline ,law ,Magnet ,business ,Instrumentation ,Spallation Neutron Source - Abstract
A new bender supermirror polarizer is used to polarize the cold neutron beam at the Fundamental Neutron Physics Beamline at the Spallation Neutron Source. We present the design of a compensation magnet that was built around the polarizer to minimize the polarizer fringe fields that could compromise the magnetic field requirements of the NPDGamma experiment for the field uniformity in the spin rotator and the field direction in the liquid hydrogen target located downstream from the polarizer. The entire magnetic field environment of the experiment has been analyzed using a finite-element model. Measurements of the magnetic field gradients and field direction have been carried out and the results are less than the upper limits required in the experiment. According to the results the compensated fields meet the stringent magnetic field requirements of the experiment defined by the systematic errors that have to be well below the statistical uncertainty of 10 −8 in our main observable, the gamma asymmetry in neutron capture on hydrogen. We describe the design of the magnetic field, the construction of the compensation magnet, and we compare results of the field measurements with the results from the model.
- Published
- 2012
32. Activating
- Author
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Weiyi, Toy, Hazel, Weir, Pedram, Razavi, Mandy, Lawson, Anne U, Goeppert, Anne Marie, Mazzola, Aaron, Smith, Joanne, Wilson, Christopher, Morrow, Wai Lin, Wong, Elisa, De Stanchina, Kathryn E, Carlson, Teresa S, Martin, Sharmeen, Uddin, Zhiqiang, Li, Sean, Fanning, John A, Katzenellenbogen, Geoffrey, Greene, José, Baselga, and Sarat, Chandarlapaty
- Subjects
Mice, Inbred BALB C ,Indoles ,Antineoplastic Agents, Hormonal ,Estradiol ,Estrogen Receptor alpha ,Mice, Nude ,Breast Neoplasms ,Xenograft Model Antitumor Assays ,Article ,Protein Domains ,Cinnamates ,Mutation ,MCF-7 Cells ,Animals ,Humans ,Female ,Estrogen Receptor Antagonists ,Fulvestrant - Abstract
Recent studies have identified somatic ESR1 mutations in patients with metastatic breast cancer (MBC) and found some of them to promote estrogen-independent activation of the receptor. The degree to which all recurrent mutants can drive estrogen-independent activities and reduced sensitivity to ER antagonists like fulvestrant is not established. In this report, we characterize the spectrum of ESR1 mutations from over 900 patients. ESR1 mutations were detected in 10%, with D538G being the most frequent (36%), followed by Y537S (14%). Several novel, activating mutations were also detected (e.g. L469V, V422del, Y537D). While many mutations lead to constitutive activity and reduced sensitivity to ER antagonists, only select mutants such as Y537S caused a magnitude of change associated with fulvestrant resistance in vivo. Correspondingly, tumors driven by Y537S, but not D5358G, E380Q or S463P were less effectively inhibited by fulvestrant than more potent and bioavailable antagonists including AZD9496. These data point to a need for antagonists with optimal pharmacokinetic properties to realize clinical efficacy against certain ESR1 mutants.
- Published
- 2015
33. Colloquium: The neutron lifetime
- Author
-
Geoffrey Greene and Fred E. Wietfeldt
- Subjects
Semileptonic decay ,Physics ,Particle physics ,Proton ,media_common.quotation_subject ,Nuclear Theory ,General Physics and Astronomy ,Electron ,Universe ,Nuclear physics ,Neutrino detector ,Nucleosynthesis ,Double beta decay ,Neutron ,Nuclear Experiment ,media_common - Abstract
The decay of the free neutron into a proton, electron, and antineutrino is the prototype semileptonic weak decay and is the simplest example of nuclear beta decay. It played a key role in the early Universe as it determined the ratio of neutrons to protons during the era of primordial light element nucleosynthesis. Neutron decay is physically related to important processes in solar physics and neutrino detection. The mean neutron lifetime has been the subject of more than 20 major experiments done, using a variety of methods, between 1950 and the present. The most precise recent measurements have stated accuracies approaching 0.1%, but are not in good agreement as they differ by as much as $5\ensuremath{\sigma}$ using quoted uncertainties. The history of neutron lifetime measurements is reviewed and the different methods used are described, giving important examples of each. The discrepancies and some systematic issues in the experiments that may be responsible are discussed, and it is shown by means of global averages that the neutron lifetime is likely to lie in the range of 880--884 s. Plans and prospects for future experiments are considered that will address these systematic issues and improve our knowledge of the neutron lifetime.
- Published
- 2011
34. Abstract 1900: Disruption of EGFR and integrin b1 signaling in triple-negative breast cancer through targeting SHC1
- Author
-
Geoffrey Greene, Ya-Fang Chang, Elizabeth Cordell, and Yuhao Wang
- Subjects
Cancer Research ,Oncology ,biology ,business.industry ,Integrin ,biology.protein ,Cancer research ,Medicine ,SHC1 ,business ,Triple-negative breast cancer - Abstract
Triple-negative breast cancer (TNBC) accounts for 15-20% of breast cancer cases and is more prevalent among young women and African American women. SHC1 (Src Homology 2 Domain Containing Transforming Protein 1) is an adaptor protein that can transmit cell surface receptor signaling and activate the Ras-ERK pathway. SHC1 is found to be overexpressed in breast cancers and is important in the regulation of tumor progression and drug resistance in ER+ breast cancer. Elevated SHC1 correlates with poor prognosis in breast cancer patients. However, the biological significance of SHC1 in TNBC is not known. In this study, we performed siRNA-mediated knockdown to determine the importance of SHC1 in cell proliferation and drug response in TNBC. We found that although siSHC1 slightly inhibited the tumor growth of TNBC cells, siSHC1 + paclitaxel significantly decreased cell proliferation and increased caspase-3/7 activity in vitro. In invasion assays, siSHC1 significantly decreased the invasion of TNBC cells. To better understand the systemic regulation by SHC1, proteomic analysis was performed after siSHC1 or Scr transfection. Pathway analysis revealed the involvement of PI3K/AKT, FAK, and actin cytoskeleton pathways, by disruption of EGFR and integrin β1 signaling, in the control of TNBC progression and drug sensitivity. In tumor explant studies, siSHC1 significantly enhanced paclitaxel-induced tumor shrinkage and reduced lung metastasis. Our data suggest that SHC1 is a potential therapeutic target in TNBC. Citation Format: Ya-Fang Chang, Elizabeth Cordell, Yuhao Wang, Geoffrey Greene. Disruption of EGFR and integrin b1 signaling in triple-negative breast cancer through targeting SHC1 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1900.
- Published
- 2018
35. Neutron interferometric search for short-range gravity
- Author
-
Vladimir Gudkov, Hirohiko M. Shimizu, and Geoffrey Greene
- Subjects
Physics ,Nuclear and High Energy Physics ,Range (particle radiation) ,Gravity (chemistry) ,Astrophysics::High Energy Astrophysical Phenomena ,Nuclear Theory ,Neutron scattering ,Nuclear physics ,Interferometry ,Search engine ,Macroscopic scale ,Neutron ,Nuclear Experiment ,Instrumentation - Abstract
We discuss the coherent nature of neutron interactions and properties of low-energy neutrons with the view of the possibility to search for “anomalous” forces with ranges from nuclear sizes up to the macroscopic scale.
- Published
- 2009
36. Parity violation in neutron–proton capture—The NPDGamma experiment
- Author
-
Michael Gericke, W. C. Chen, Gregory S. Mitchell, A. Salas-Bacci, R. Carlini, Ricardo Alarcon, Timothy Chupp, Stuart J. Freedman, H. Nann, S. Balascuta, J. Mei, E. I. Sharapov, R. C. Gillis, R. Mahurin, M. B. Leuschner, S. I. Penttilä, Yasuhiro Masuda, Thomas R. Gentile, V.W. Yuan, Bernhard Lauss, D. Ramsay, B. Losowki, Gordon L. Jones, S. Covrig, Geoffrey Greene, L. Barron, Takashi Ino, S. Santra, Suguru Muto, C. Crawford, W. M. Snow, F. W. Hersman, S. A. Page, T. B. Smith, J. D. Bowman, M. Sharma, P. N. Seo, W. S. Wilburn, and M. Dabaghyan
- Subjects
Nuclear reaction ,Physics ,Nuclear and High Energy Physics ,Particle physics ,media_common.quotation_subject ,Asymmetry ,Nuclear physics ,Neutron capture ,Neutron source ,Spallation ,Neutron ,Nuclear Experiment ,Nucleon ,Instrumentation ,Spallation Neutron Source ,media_common - Abstract
The NPDGamma collaboration has recently completed the first phase of a measurement to determine the size of the weak nucleon–nucleon interaction from cold neutron capture on a liquid hydrogen target. In the framework of the nearly 30 year old DDH model [B. Desplanques, J.F. Donoghue, B.R. Holstein, Annals of Physics 124 (1980) 449], the measured process is explained in terms of the weak pion–nucleon coupling, while the framework of modern effective field theory parameterizes the measured process in terms of the S 1 3 - P 1 3 , long range transition (essentially the Danilov parameter ρ t ) [S.L. Zhu et al., Nuclear Physics A 748 (2005) 435; C.-P. Liu, Phys. Rev. C 75 (2007) 065501]. The couplings in terms of either model are directly proportional to the parity violating up-down asymmetry in the angular distribution of gamma rays with respect to the neutron spin direction in the reaction n ⇒ + p → d + γ . The asymmetry has a predicted size of 5 × 10 - 8 and the aim of the NPDGamma collaboration is to measure it to 20%. The first phase of the measurement was completed at the Los Alamos National Laboratory Neutron Science Center Spallation Source with a preliminary result of ( - 1.1 ± 2.1 stat . ± 0.2 sys . ) × 10 - 7 . Here, we report on the measurements and the results obtained so far. The experiment is currently being installed at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory, for the remainder of its run time.
- Published
- 2009
37. Optimization of the ballistic guide design for the SNS FNPB 8.9Å neutron line
- Author
-
Takeyasu M. Ito, Geoffrey Greene, and Christopher B. Crawford
- Subjects
Physics ,Nuclear and High Energy Physics ,Physics - Instrumentation and Detectors ,business.industry ,Monte Carlo method ,FOS: Physical sciences ,Instrumentation and Detectors (physics.ins-det) ,Neutron physics ,Optics ,Beamline ,Neutron flux ,Section (archaeology) ,Line (geometry) ,Physics::Accelerator Physics ,Neutron ,Nuclear Experiment (nucl-ex) ,business ,Nuclear Experiment ,Instrumentation - Abstract
The optimization of the ballistic guide design for the SNS Fundamental Neutron Physics Beamline 8.9 A line is described. With a careful tuning of the shape of the curve for the tapered section and the width of the straight section, this optimization resulted in more than 75% increase in the neutron flux exiting the 33 m long guide over a straight m=3.5 guide with the same length., Comment: 21 pages, 13 figures; added a paragraph on existing ballistic guides to respond to referee comments; accepted for publication in Nuclear Inst. and Methods in Physics Research, A
- Published
- 2006
38. Polarized neutrons for pulsed neutron sources
- Author
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Geoffrey Greene, Tom Gentile, Jeremy Cook, A. A. Parizzi, Gain Felcher, Frank Klose, Eddy Lelievre-Berna, Jinkui Zhao, Ian S. Anderson, Roger Pynn, and Tom Koetzle
- Subjects
Physics ,Nuclear and High Energy Physics ,Astrophysics::High Energy Astrophysical Phenomena ,Nuclear engineering ,Nuclear Theory ,Neutron scattering ,Neutron radiation ,Neutron spin echo ,Nuclear physics ,Nuclear Energy and Engineering ,Neutron source ,Neutron detection ,Neutron ,Spallation ,Nuclear Experiment ,Spin-½ - Abstract
Polarized neutrons provide a powerful tool for research at today's continuous neutron sources, permitting unique information to be obtained from neutron-scattering experiments and in the area of fundamental neutron physics. The information obtained is indispensable to important areas of current research such as magnetism, spin fluctuations in correlated-electron materials, nanoscience, astrophysics, and cosmology. Unfortunately, the polarized neutron capabilities that already exist at reactor neutron sources, mainly in Europe, cannot be transferred directly to pulsed spallation sources because many of the devices used at reactors to manipulate neutron spins operate only at a single neutron wavelength or with a neutron beam of limited divergence. Both of these restrictions must be overcome for devices to be useful at pulsed spallation sources. This report identifies the significant R&D efforts that will be required to achieve these goals. These efforts must be undertaken now, if they are to be useful early...
- Published
- 2005
39. The Fundamental Neutron Physics Beamline at the Spallation Neutron Source
- Author
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John M. Doyle, C. R. Gould, P. R. Huffman, M. D. Cooper, P. E. Koehler, R.R. Allen, V. Cianciolo, W. M. Snow, David Bowman, and Geoffrey Greene
- Subjects
Physics ,Astrophysics::High Energy Astrophysical Phenomena ,Nuclear Theory ,General Engineering ,Neutron scattering ,fundamental neutron physics ,Neutron time-of-flight scattering ,Article ,spallation neutron source ,Nuclear physics ,neutron source ,Beamline ,Ultracold neutrons ,Neutron source ,Neutron detection ,Physics::Accelerator Physics ,Neutron ,Nuclear Experiment ,Spallation Neutron Source - Abstract
The Spallation Neutron Source (SNS), currently under construction at Oak Ridge National Laboratory with an anticipated start-up in early 2006, will provide the most intense pulsed beams of cold neutrons in the world. At a projected power of 1.4 MW, the time averaged fluxes and fluences of the SNS will approach those of high flux reactors. One of the flight paths on the cold, coupled moderator will be devoted to fundamental neutron physics. The fundamental neutron physics beamline is anticipated to include two beam-lines; a broad band cold beam, and a monochromatic beam of 0.89 nm neutrons for ultracold neutron (UCN) experiments. The fundamental neutron physics beamline will be operated as a user facility with experiment selection based on a peer reviewed proposal process. An initial program of five experiments in neutron decay, hadronic weak interaction and time reversal symmetry violation have been proposed.
- Published
- 2005
40. A measurement of the Flight Path 12 cold H2 moderator brightness at LANSCE
- Author
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P.-N. Seo, S. I. Penttilä, W. S. Wilburn, Gregory S. Mitchell, Michael Gericke, J. D. Bowman, Janet C. Long, and Geoffrey Greene
- Subjects
Physics ,Nuclear and High Energy Physics ,Brightness ,business.industry ,Collimator ,Scintillator ,Neutron temperature ,Particle detector ,law.invention ,Time of flight ,Optics ,law ,Scintillation counter ,Neutron ,Nuclear Experiment ,business ,Instrumentation - Abstract
We have measured the brightness of the Flight Path 12 upstream/back-scattering partially coupled cold hydrogen moderator at LANSCE. This measurement was performed in the neutron energy range of 0.8–76.9 meV by using a time-of-flight technique in conjunction with a two-pinhole collimator system. Cold neutrons were observed with a redundant 6Li-loaded glass scintillation detector having an efficiency of close to unity. The detector viewed an area of 0.93 cm2 on the center of the 12×12 cm2 moderator surface. A maximum brightness of 1.25×108 neutrons s−1 sr−1 cm−2 meV−1 μA−1 was measured at 3.3-meV neutron energy. Statistical and systematic errors of the measurement are 3% and 7%, respectively. The measured brightness is compared to the result of a model calculation and there is a significant disagreement, by a factor of 1.5 at the peak. The performance of the m=3 supermirror neutron guide system on Flight Path 12 was also studied with the two pinhole-detector system.
- Published
- 2004
41. A cryogenic radiometer for absolute neutron rate measurement
- Author
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W. M. Snow, Alan K. Thompson, Z. Chowdhuri, Fred E. Wietfeldt, W. M. Lozowski, G. Hansen, David M. Gilliam, C. D. Keith, Jeffrey S. Nico, Maynard S. Dewey, V. Jane, and Geoffrey Greene
- Subjects
Materials science ,Radiometer ,business.industry ,Astrophysics::Instrumentation and Methods for Astrophysics ,Cryogenics ,Neutron radiation ,Fluence ,Neutron temperature ,Physics::Geophysics ,Neutron capture ,Optics ,Neutron detection ,Neutron ,business ,Instrumentation ,Physics::Atmospheric and Oceanic Physics - Abstract
We detail the design and operation of an electrical substitution radiometer, which measures the absolute fluence of thermal neutron beams based on neutron absorption in a 6Li-rich metallic alloy. We demonstrate that the device possesses a linear response to electrical power in the 50–500 nW range with better than 0.1% absolute accuracy and negligible zero offset. We show the response of the radiometer to a 3 meV neutron beam. We compare the noise of the radiometer to the noise observed upstream in a thin rate monitor and show that the radiometer noise is understood quantitatively. We establish that the radiometer measures neutron rates above 105 s−1 to an absolute accuracy of 0.1%.
- Published
- 2003
42. Using Focus Groups for Instrument Development
- Author
-
RD Geoffrey Greene PhD, RN Susan Rossi PhD, Faith Lees Ms, RN Cynthia A. Padula PhD, RD Nancy Fey-Yensan PhD, Claudio R. Nigg, and Phillip Clark ScD
- Subjects
Consumption (economics) ,Nutrition and Dietetics ,Food frequency ,business.industry ,Applied psychology ,Behavior change ,Transtheoretical model ,Medicine (miscellaneous) ,Medicine ,Geriatrics and Gerontology ,business ,Social psychology ,Focus group - Abstract
The purpose of this focus group research was to identify themes related to fruit and vegetable consumption in older adults that could be used as the basis for instrument development. The Transtheoretical Model of Behavior Change (TTM) was used as a framework to guide this research. Adults over the age of 60 completed a food frequency screener, and were designated into “low” and “high” fruit and vegetable intake groups. Participants responded to some general as well as stage-specific questions, dependent upon group. Data were analyzed by two independent researchers, and level of agreement was consistently high. Data reduction was accomplished by identification of inductively derived themes. The derived themes made conceptual and operational sense, and were used as a basis for development of quantitative measures related to fruit and vegetable consumption of older adults. Instrument development represents an exciting application of focus group research that deserves increased attention.
- Published
- 2003
43. Neutron decay correlations in the Nab experiment
- Author
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C. Hendrus, W. Farrar, J. Wexler, P. E. Mueller, R. Mammei, G. W. Dodson, A. Smith, J. R. Calarco, E. Frlež, Ricardo Alarcon, Christopher Crawford, Vladimir Gudkov, K. P. Rykaczewski, John Ramsey, S. A. Page, A. Salas-Bacci, M. Martinez, J. Fry, Geoffrey Greene, B. Plaster, J. Dubois, Susanne Mertens, J. D. Bowman, Takeyasu M. Ito, F. W. Hersman, L. Barrón Palos, Mark Makela, J. Mirabal-Martinez, Seppo Penttila, Juliette Mammei, Eric Stevens, Ferenc Glück, W. S. Wilburn, Nadia Fomin, Sky Sjue, Wenjiang Fan, J. Caylor, N. Birge, J. W. Martin, R. Picker, D. C. Radford, Aaron Sprow, Albert Young, S. Baeßler, Dinko Pocanic, T. Bode, T. Brunst, Michael Gericke, R. Whitehead, P. L. McGaughey, N. Macsai, B. A. Zeck, Timothy Chupp, Hui Li, E. M. Scott, Robert Grzywacz, V. Cianciolo, E. Smith, and Leah Broussard
- Subjects
Physics ,History ,010308 nuclear & particles physics ,Nuclear Theory ,01 natural sciences ,Measure (mathematics) ,Computer Science Applications ,Education ,Term (time) ,Nuclear physics ,0103 physical sciences ,Beta particle ,High Energy Physics::Experiment ,Neutron ,Nuclear Experiment ,010306 general physics ,Beta (finance) - Abstract
The Nab experiment will measure the correlation a between the momenta of the beta particle and antineutrino in neutron decay as well as the Fierz term b which distorts the beta spectrum.
- Published
- 2017
44. A Technique For Determining Neutron Beam Fluence to 0.01% Uncertainty
- Author
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Jeffrey S. Nico, Nadia Fomin, David M. Gilliam, A. Yue, Maynard S. Dewey, Fred E. Wietfeldt, Geoffrey Greene, and W. M. Snow
- Subjects
Physics ,Bonner sphere ,business.industry ,Astrophysics::High Energy Astrophysical Phenomena ,Nuclear Theory ,Neutron stimulated emission computed tomography ,Neutron scattering ,Neutron temperature ,Nuclear physics ,Neutron capture ,Optics ,Neutron cross section ,Neutron detection ,Neutron ,Nuclear Experiment ,business - Abstract
The achievable uncertainty in neutron lifetime measurements using the beam technique has been limited by the uncertainty in the determination of the neutron density in the decay volume. In the Sussex-ILL-NIST series of beam lifetime experiments, the density was determined with a neutron fluence mon itor that detected the charged particle products from neutron absorption in a thin layer of 6Li or lOB. In each of the experiments, the absolute detection efficiency of the neutron monitor was determined from the measured density of the neutron absorber, the thermal neutron cross section for the absorbing ma terial, and the solid angle of the charged particle detectors. The efficiency of the neutron monitor used in the most recent beam lifetime experiment has since been measured directly by operating it on a monochromatic neutron beam in which the total neutron rate is determined with a totally absorbing neutron detector. The absolute nature of this technique does not rely on any knowl edge of neutron absorption cross sections or a measurement of the density of the neutron absorbing deposit. This technique has been used to measure the neutron monitor efficiency to 0.06% uncertainty. VVe show that a new monitor and absolute neutron detector employingmore » the same technique would be capable of achieving determining neutron fluence to an uncertainty of 0.01%.« less
- Published
- 2014
45. Studies of a solid-deuterium source for ultra-cold neutrons
- Author
-
P. Geltenbort, R. R. Tal’daev, V Shustov, M. Sazhin, A. A. Zakharov, V. E. Varlamov, M. S. Lasakov, A. P. Serebrov, S. J. Seestrom, Atanas Vasilev, V Kuz'minov, A. V. Aldushchenkov, Geoffrey Greene, V. A. Mityukhlyaev, T. J. Bowles, R. Hill, and A. G. Kharitonov
- Subjects
Physics ,Nuclear and High Energy Physics ,Hydrogen ,Isotope ,Analytical chemistry ,chemistry.chemical_element ,Nuclear physics ,chemistry ,Deuterium ,Yield (chemistry) ,Ultracold neutrons ,Neutron source ,Neutron ,Nucleon ,Instrumentation - Abstract
The results of experiments and calculations for a solid-deuterium UCN source are presented. It was experimentally shown that the UCN yield is increased by a factor 3 at the solidification of liquid deuterium and a factor 10 at a temperature 10 K, with respect to the liquid phase. The gain factor for UCN yield with respect to hydrogen gas or deuterium gas at room temperature is equal to 1230.
- Published
- 2000
46. A Man with Inflamed Ears
- Author
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Harold M. Adelman, Bryan Bognar, Edward P. Cutolo, Joanne Valeriano-Marcet, Charlotte A. Truitt, Rajani P. Shah, Vipul R. Shah, Daniel Reichmuth, and Geoffrey Greene
- Subjects
Adult ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,Arthritis ,law.invention ,Prednisone ,law ,Biopsy ,Humans ,Medicine ,Polychondritis, Relapsing ,Ear, External ,Hepatitis ,medicine.diagnostic_test ,business.industry ,Arthrocentesis ,General Medicine ,Respiration Disorders ,medicine.disease ,Rash ,Surgery ,Gram staining ,medicine.anatomical_structure ,Bone marrow ,medicine.symptom ,business ,medicine.drug - Abstract
A 23-year-old man presented with fever, dyspnea, nonproductive cough, left eye redness, reduced vision, and bilateral ear pain and tenderness. The symptoms had begun two days earlier, eight days after he was discharged from the hospital with a presumptive diagnosis of Still's disease. He was first seen a month before the current admission for complaints of fever (as high as 39.4 degrees C), nonproductive cough, and asymmetric arthritis. The workup at that time included arthrocentesis of the right knee. Analysis of the joint fluid showed 7,500 white blood cells/mm3 and no crystals. A gram stain and culture of the fluid were negative. HIV and hepatitis tests, bone marrow biopsy and culture, transesophageal echocardiography, abdominal computed tomography, radionuclide bone scanning, and rheumatologic tests failed to identify the problem. The development of an evanescent macular pink rash on day 15 suggested the possibility of Still's disease. Treatment with prednisone (40 mg po qd) was initiated, and the patient was discharged on day 19.
- Published
- 1999
47. Improved Determination of the Neutron Lifetime
- Author
-
W. M. Snow, Jeffrey S. Nico, A. Yue, David M. Gilliam, A. Laptev, Maynard S. Dewey, Fred E. Wietfeldt, and Geoffrey Greene
- Subjects
Physics ,Neutron monitor ,010308 nuclear & particles physics ,Solid angle ,General Physics and Astronomy ,FOS: Physical sciences ,Neutron radiation ,01 natural sciences ,Charged particle ,Neutron temperature ,Nuclear physics ,0103 physical sciences ,Neutron detection ,Neutron ,High Energy Physics::Experiment ,Absorption (logic) ,Nuclear Experiment (nucl-ex) ,010306 general physics ,Nuclear Experiment - Abstract
The most precise determination of the neutron lifetime using the beam method was completed in 2005 and reported a result of $\tau_n = (886.3 \pm 1.2 [\textrm{stat}] \pm 3.2 [\textrm{syst}])$ s. The dominant uncertainties were attributed to the absolute determination of the fluence of the neutron beam (2.7 s). The fluence was measured with a neutron monitor that counted the neutron-induced charged particles from absorption in a thin, well-characterized 6Li deposit. The detection efficiency of the monitor was calculated from the areal density of the deposit, the detector solid angle, and the evaluated nuclear data file, ENDF/B-VI 6Li(n,t)4He thermal neutron cross section. In the current work, we have measured the detection efficiency of the same monitor used in the neutron lifetime measurement with a second, totally-absorbing neutron detector. This direct approach does not rely on the 6Li(n,t)4He cross section or any other nuclear data. The detection efficiency is consistent with the value used in 2005 but was measured with a precision of 0.057 %, which represents a five-fold improvement in the uncertainty. We have verified the temporal stability of the neutron monitor through ancillary measurements, allowing us to apply the measured neutron monitor efficiency to the lifetime result from the 2005 experiment. The updated lifetime is $\tau_n = (887.7 \pm 1.2 [\textrm{stat}] \pm 1.9 [\textrm{syst}])$ s., Comment: v2 - Updated article with revisions made during editorial process, journal citation and DOI added. v1 - Draft article as submitted to Phys. Rev. Lett. (plus a few changes from institution review)
- Published
- 2013
48. The 'Green Eating' project: a pilot intervention to promote sustainable and healthy eating in college students
- Author
-
Jessica Nash, Kelleigh Eastman, Norbert Mundorf, and Geoffrey Greene
- Subjects
Gerontology ,business.industry ,Intervention (counseling) ,Environmental resource management ,Sustainability ,Genetics ,Stage of change ,Healthy eating ,business ,Psychology ,Molecular Biology ,Biochemistry ,Biotechnology - Published
- 2013
49. Neutron Beta Decay Studies with Nab
- Author
-
L. P. Alonzi, T. V. Vianciolo, Robert Grzywacz, K. P. Rykaczewski, Vladimir Gudkov, A. Salas-Bacci, S. Balascuta, S. McGovern, D. Harrison, L. Barrón-Palos, Christopher Crawford, M. Bychkov, A. R. Young, F. Glück, Seppo Penttila, W. S. Wilburn, F. W. Hersman, P. L. McGaughey, S. A. Page, Daniel Wagner, J. W. Martin, Takeyasu M. Ito, S. Baeßler, Ricardo Alarcon, Geoffrey Greene, J. R. Calarco, E. Frlež, Mark Makela, Michael Gericke, J. D. Bowman, J. Byrne, Dinko Pocanic, Timothy Chupp, and Z. Tompkins
- Subjects
Coupling constant ,Physics ,Nuclear physics ,Spectrometer ,FOS: Physical sciences ,Neutron ,Nuclear Experiment (nucl-ex) ,Nuclear Experiment ,Beta decay ,Standard Model - Abstract
Precision measurements in neutron beta decay serve to determine the coupling constants of beta decay and allow for several stringent tests of the standard model. This paper discusses the design and the expected performance of the Nab spectrometer., Submitted to Proceedings of the Conference CIPANP12, St.Petersburg, Florida, May 2012
- Published
- 2012
50. Multidomain Assembly of Nuclear Estrogen Receptors: Structural Insights into ER-Positive Breast Cancer Therapeutics
- Author
-
Geoffrey Greene
- Subjects
DNA binding site ,Transcriptional activity ,Multi domain ,Estrogen receptor ,Computational biology ,Biology ,Bioinformatics ,Solution structure - Abstract
The major goal of this project is to determine and compare the overall dynamic architectures of both ERs bound to different known DNA response elements (EREs). This study combines small-angle X-ray solution scattering (SAXS) data and computational modeling to address the multimeric assembly of ER DBD-hinge-LBD complexes. To date, we have successfully modeled ER CDE bound to its cognate DNA binding site and generated homogenous ER DBD-hinge-LDB protein samples (ER CDEF) needed for SAXS studies. We have also collected SAXS data on ER CDEF, but not ER CDE. We will continue to generate and compare the ER CDE and CDEF fragments for small angle x-ray scattering (SAXS) analyses of ER multidomain fragments EREs and various peptides to obtain solution structure information. Having worked out the conditions for the expression and purification of ER CDEF, we do not expect difficulties in the expression and purification of ER CDE domain. By integrating SAXS analyses and computational biology, we expect to better understand ER multi-domain assembly mechanisms. It is anticipated that this information will help explain how domain interfaces in ER/ERE complexes modulate ligand-dependent transcriptional activity in response to various SERMs, providing novel structural insights that will facilitate improved targeting of ER-positive breast cancers, especially those that are refractory to current adjuvant therapies.
- Published
- 2012
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