53 results
Sex-dependent differences in vulnerability to early risk factors for posttraumatic stress disorder: results from the AURORA study
- Stephanie Haering, Antonia V. Seligowski, Sarah D. Linnstaedt, Vasiliki Michopoulos, Stacey L. House, Francesca L. Beaudoin, Xinming An, Thomas C. Neylan, Gari D. Clifford, Laura T. Germine, Scott L. Rauch, John P. Haran, Alan B. Storrow, Christopher Lewandowski, Paul I. Musey, Jr., Phyllis L. Hendry, Sophia Sheikh, Christopher W. Jones, Brittany E. Punches, Robert A. Swor, Nina T. Gentile, Lauren A. Hudak, Jose L. Pascual, Mark J. Seamon, Claire Pearson, David A. Peak, Roland C. Merchant, Robert M. Domeier, Niels K. Rathlev, Brian J. O'Neil, Leon D. Sanchez, Steven E. Bruce, Steven E. Harte, Samuel A. McLean, Ronald C. Kessler, Karestan C. Koenen, Jennifer S. Stevens, Abigail Powers
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- Journal:
- Psychological Medicine , First View
- Published online by Cambridge University Press:
- 22 May 2024, pp. 1-11
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Background
Knowledge of sex differences in risk factors for posttraumatic stress disorder (PTSD) can contribute to the development of refined preventive interventions. Therefore, the aim of this study was to examine if women and men differ in their vulnerability to risk factors for PTSD.
MethodsAs part of the longitudinal AURORA study, 2924 patients seeking emergency department (ED) treatment in the acute aftermath of trauma provided self-report assessments of pre- peri- and post-traumatic risk factors, as well as 3-month PTSD severity. We systematically examined sex-dependent effects of 16 risk factors that have previously been hypothesized to show different associations with PTSD severity in women and men.
ResultsWomen reported higher PTSD severity at 3-months post-trauma. Z-score comparisons indicated that for five of the 16 examined risk factors the association with 3-month PTSD severity was stronger in men than in women. In multivariable models, interaction effects with sex were observed for pre-traumatic anxiety symptoms, and acute dissociative symptoms; both showed stronger associations with PTSD in men than in women. Subgroup analyses suggested trauma type-conditional effects.
ConclusionsOur findings indicate mechanisms to which men might be particularly vulnerable, demonstrating that known PTSD risk factors might behave differently in women and men. Analyses did not identify any risk factors to which women were more vulnerable than men, pointing toward further mechanisms to explain women's higher PTSD risk. Our study illustrates the need for a more systematic examination of sex differences in contributors to PTSD severity after trauma, which may inform refined preventive interventions.
South American Maize and Political Economy of the Middle and Late Formative Soconusco Region of Guatemala
- Thomas C. Hart, Neil A. Duncan, Deborah M. Pearsall, Michael W. Love
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- Journal:
- Latin American Antiquity , First View
- Published online by Cambridge University Press:
- 15 June 2023, pp. 1-14
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We present macrobotanical, starch, and phytolith data from artifacts and sediments from Middle Formative La Blanca (1000–600 cal BC) and Late Formative El Ujuxte (600 cal BC–cal AD 115 ) in the Soconusco region in Guatemala. Potential economic plants identified included palm (cf. Arecaceae), two varieties of maize (Zea mays), guava (Psidium guajava), bean (Phaseolus), chili peppers (Capsicum), squash (Cucurbitaceae), custard apple (Annonaceae), coco plum (Chrysobalanaceae), lerén (Calathea), arrowroot (Maranta), and bird-of-paradise (Heliconia). The results suggest that control of food production and consumption was critical for the transition from complex chiefdoms during the Middle Formative to the archaic state in the Late Formative. The arrival of a more productive South American variety of maize at El Ujuxte (about 2549 BP) allowed elites to exploit an already existing broad-based economic system and to use the maize-based religious system to increase control over maize agricultural practices and maintain power through ideology and disciplinary power. These data suggest that the arrival of fully domesticated South American maize likely influenced the overall development of Mesoamerican state-level societies.
Associations of alcohol and cannabis use with change in posttraumatic stress disorder and depression symptoms over time in recently trauma-exposed individuals
- Cecilia A. Hinojosa, Amanda Liew, Xinming An, Jennifer S. Stevens, Archana Basu, Sanne J. H. van Rooij, Stacey L. House, Francesca L. Beaudoin, Donglin Zeng, Thomas C. Neylan, Gari D. Clifford, Tanja Jovanovic, Sarah D. Linnstaedt, Laura T. Germine, Scott L. Rauch, John P. Haran, Alan B. Storrow, Christopher Lewandowski, Paul I. Musey, Phyllis L. Hendry, Sophia Sheikh, Christopher W. Jones, Brittany E. Punches, Michael C. Kurz, Robert A. Swor, Lauren A. Hudak, Jose L. Pascual, Mark J. Seamon, Elizabeth M. Datner, Anna M. Chang, Claire Pearson, David A. Peak, Roland C. Merchant, Robert M. Domeier, Niels K. Rathlev, Paulina Sergot, Leon D. Sanchez, Steven E. Bruce, Mark W. Miller, Robert H. Pietrzak, Jutta Joormann, Diego A. Pizzagalli, John F. Sheridan, Steven E. Harte, James M. Elliott, Ronald C. Kessler, Karestan C. Koenen, Samuel A. McLean, Kerry J. Ressler, Negar Fani
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- Journal:
- Psychological Medicine / Volume 54 / Issue 2 / January 2024
- Published online by Cambridge University Press:
- 13 June 2023, pp. 338-349
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Background
Several hypotheses may explain the association between substance use, posttraumatic stress disorder (PTSD), and depression. However, few studies have utilized a large multisite dataset to understand this complex relationship. Our study assessed the relationship between alcohol and cannabis use trajectories and PTSD and depression symptoms across 3 months in recently trauma-exposed civilians.
MethodsIn total, 1618 (1037 female) participants provided self-report data on past 30-day alcohol and cannabis use and PTSD and depression symptoms during their emergency department (baseline) visit. We reassessed participant's substance use and clinical symptoms 2, 8, and 12 weeks posttrauma. Latent class mixture modeling determined alcohol and cannabis use trajectories in the sample. Changes in PTSD and depression symptoms were assessed across alcohol and cannabis use trajectories via a mixed-model repeated-measures analysis of variance.
ResultsThree trajectory classes (low, high, increasing use) provided the best model fit for alcohol and cannabis use. The low alcohol use class exhibited lower PTSD symptoms at baseline than the high use class; the low cannabis use class exhibited lower PTSD and depression symptoms at baseline than the high and increasing use classes; these symptoms greatly increased at week 8 and declined at week 12. Participants who already use alcohol and cannabis exhibited greater PTSD and depression symptoms at baseline that increased at week 8 with a decrease in symptoms at week 12.
ConclusionsOur findings suggest that alcohol and cannabis use trajectories are associated with the intensity of posttrauma psychopathology. These findings could potentially inform the timing of therapeutic strategies.
Iodine fortification of plant-based dairy and fish alternatives: the effect of substitution on iodine intake based on a market survey in the UK
- Katie Nicol, Eva-Leanne Thomas, Anne P. Nugent, Jayne V. Woodside, Kathryn H. Hart, Sarah C. Bath
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- Journal:
- British Journal of Nutrition / Volume 129 / Issue 5 / 14 March 2023
- Published online by Cambridge University Press:
- 04 April 2022, pp. 832-842
- Print publication:
- 14 March 2023
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Milk, dairy products, and fish are the main sources of iodine in the UK. Plant-based products are increasingly popular, especially with young women, which may affect iodine intake as they are naturally low in iodine; this is concerning as iodine is required for fetal brain development. We, aimed to (i) assess the iodine fortification of products sold as alternatives to milk, yoghurt, cheese and fish through a cross-sectional survey of UK retail outlets in 2020, and (ii) model the impact of substitution with such products on iodine intake, using portion-based scenarios. We identified 300 products, including plant-based alternatives to: (i) milk (n 146); (ii) yoghurt (n 76); (iii) cheese (n 67) and (iv) fish (n 11). After excluding organic products (n 48), which cannot be fortified, only 28 % (n 29) of milk alternatives and 6 % (n 4) of yoghurt alternatives were fortified with iodine, compared with 88 % (n 92) and 73 % (n 51), respectively, with Ca. No cheese alternative was fortified with iodine, but 55 % were fortified with Ca. None of the fish alternatives were iodine fortified. Substitution of three portions of dairy product (milk/yoghurt/cheese) per day with unfortified alternatives would reduce the iodine provided by 97·9 % (124 v. 2·6 µg) and substantially reduce the contribution to the adult intake recommendation (150 µg/d; 83 v. 1·8 %). Our study highlights that the majority of plant-based alternatives are not iodine fortified and that the use of unfortified alternatives put consumers at risk of iodine deficiency.
Socio-demographic and trauma-related predictors of depression within eight weeks of motor vehicle collision in the AURORA study
- Jutta Joormann, Samuel A. McLean, Francesca L. Beaudoin, Xinming An, Jennifer S. Stevens, Donglin Zeng, Thomas C. Neylan, Gari Clifford, Sarah D. Linnstaedt, Laura T. Germine, Scott L. Rauch, Paul I. Musey, Phyllis L. Hendry, Sophia Sheikh, Christopher W. Jones, Brittany E. Punches, Gregory Fermann, Lauren A. Hudak, Kamran Mohiuddin, Vishnu Murty, Meghan E. McGrath, John P. Haran, Jose Pascual, Mark Seamon, David A. Peak, Claire Pearson, Robert M. Domeier, Paulina Sergot, Roland Merchant, Leon D. Sanchez, Niels K. Rathlev, William F. Peacock, Steven E. Bruce, Deanna Barch, Diego A. Pizzagalli, Beatriz Luna, Steven E. Harte, Irving Hwang, Sue Lee, Nancy Sampson, Karestan C. Koenen, Kerry J. Ressler, Ronald C. Kessler
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- Journal:
- Psychological Medicine / Volume 52 / Issue 10 / July 2022
- Published online by Cambridge University Press:
- 29 October 2020, pp. 1934-1947
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Background
This is the first report on the association between trauma exposure and depression from the Advancing Understanding of RecOvery afteR traumA(AURORA) multisite longitudinal study of adverse post-traumatic neuropsychiatric sequelae (APNS) among participants seeking emergency department (ED) treatment in the aftermath of a traumatic life experience.
MethodsWe focus on participants presenting at EDs after a motor vehicle collision (MVC), which characterizes most AURORA participants, and examine associations of participant socio-demographics and MVC characteristics with 8-week depression as mediated through peritraumatic symptoms and 2-week depression.
ResultsEight-week depression prevalence was relatively high (27.8%) and associated with several MVC characteristics (being passenger v. driver; injuries to other people). Peritraumatic distress was associated with 2-week but not 8-week depression. Most of these associations held when controlling for peritraumatic symptoms and, to a lesser degree, depressive symptoms at 2-weeks post-trauma.
ConclusionsThese observations, coupled with substantial variation in the relative strength of the mediating pathways across predictors, raises the possibility of diverse and potentially complex underlying biological and psychological processes that remain to be elucidated in more in-depth analyses of the rich and evolving AURORA database to find new targets for intervention and new tools for risk-based stratification following trauma exposure.
17 - Can We Universally Accommodate Mental Health and Should We? A Systematic Review of the Evidence and Ethical Analysis
- from Part VI - Quantifying Disability
- Edited by I. Glenn Cohen, Harvard Law School, Massachusetts, Carmel Shachar, Harvard Law School, Massachusetts, Anita Silvers, San Francisco State University, Michael Ashley Stein, Harvard Law School, Massachusetts
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- Disability, Health, Law, and Bioethics
- Published online:
- 08 April 2020
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- 23 April 2020, pp 227-241
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Summary
The social model of disability was implemented in the United States partially through the Americans with Disabilities Act (ADA), and most notably through certain universal accommodations for physical disabilities. The social model has also been applied to mental health, but the ADA did not provide for universal accommodations in mental health. In this Chapter, the authors conduct a systematic review of PubMed and PsycARTICLES to identify evidence for potential universal accommodations in mental health and discuss the policy and ethical considerations of implementing universal accommodations in mental health.
Neuropsychological Characteristics of the Confusional State Following Traumatic Brain Injury
- Rachel E. Keelan, Elaine J. Mahoney, Mark Sherer, Tessa Hart, Joseph Giacino, Yelena G. Bodien, Risa Nakase-Richardson, Kristen Dams-O’Connor, Thomas A. Novack, Rodney D. Vanderploeg
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- Journal of the International Neuropsychological Society / Volume 25 / Issue 3 / March 2019
- Published online by Cambridge University Press:
- 25 January 2019, pp. 302-313
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Objectives: Individuals with moderate–severe traumatic brain injury (TBI) experience a transitory state of impaired consciousness and confusion often called posttraumatic confusional state (PTCS). This study examined the neuropsychological profile of PTCS. Methods: Neuropsychometric profiles of 349 individuals in the TBI Model Systems National Database were examined 4 weeks post-TBI (±2 weeks). The PTCS group was subdivided into Low (n=46) and High Performing PTCS (n=45) via median split on an orientation/amnesia measure, and compared to participants who had emerged from PTCS (n=258). Neuropsychological patterns were examined using multivariate analyses of variance and mixed model analyses of covariance. Results: All groups were globally impaired, but severity differed across groups (F(40,506)=3.44; p<.001; ŋp2 =.206). Rate of forgetting (memory consolidation) was impaired in all groups, but failed to differentiate them (F(4,684)=0.46; p=.762). In contrast, executive memory control was significantly more impaired in PTCS groups than the emerged group: Intrusion errors: F(2,343)=8.78; p<.001; ŋp2=.049; False positive recognition errors: F(2,343)=3.70; p<.05; ŋp2=.021. However, non-memory executive control and other executive memory processes did not differentiate those in versus emerged from PTCS. Conclusions: Executive memory control deficits in the context of globally impaired cognition characterize PTCS. This pattern differentiates individuals in and emerged from PTCS during the acute recovery period following TBI. (JINS, 2019, 25, 302–313)
2367: Defining critical features of the immune microenvironment in melanoma using multiplex immunohistochemistry and spatial analysis
- Robyn Gartrell, Douglas Marks, Thomas Hart, Yan Lu, Ed Stack, Camden Esancy, Basil Horst, Yvonne Saenger, Camille Gerard, Dan Tong Jia, Paul Armenta, Daisuke Izaki, Kristen Beck
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- Journal:
- Journal of Clinical and Translational Science / Volume 1 / Issue S1 / September 2017
- Published online by Cambridge University Press:
- 10 May 2018, pp. 62-63
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OBJECTIVES/SPECIFIC AIMS: Precise biomarkers are urgently needed to characterize the tumor immune microenvironment in primary melanoma tumors both for prognostication and to predict the benefit of immuno-therapeutic intervention. The goal of this work is to define spatial relationships between CD8+ T cells, CD68+ macrophages and Sox10+ melanoma cells in order to define features correlating with prolonged survival METHODS/STUDY POPULATION: Five micrometer slides from either the primary biopsy or subsequent wide local excision procedure were stained using Opal multiplex IHC for DAPI, CD3 (LN10, Leica), CD8 (4B11, Leica), CD68 (KP1, Biogenex), SOX10 (BC34, Biocare), HLA-DR (LN-3, Abcam), and Ki67 (MIB1, Abcam). Cell phenotypes within representative fields preselected by a trained dermato-pathologist and were visualized using the Mantra quantitative pathology workstation (PerkinElmer), and analysis of spatial distribution of CD3+ CD8+ cells analyzed using inForm® image analysis software (PerkinElmer), and Spotfire software (TIBCO). In order to test whether mIHC can better characterize the tumor immune microenvironment, we screened databases at the Herbert Irving Cancer Center (HICC) at Columbia University for stage II/III melanoma patients diagnosed between 2000 and 2012, with available FFPE of primary melanoma tissue and documented clinical follow-up. We identified a preliminary population of 57 patients to begin our analysis. Clinical follow-up was available on 35 patients of whom 21 patients were alive with no evidence of recurrence or died with no evidence of recurrence and 14 had died of melanoma. Twenty-four patients had more than 24 months of survival information available but no detailed clinical information to determine cause of death. RESULTS/ANTICIPATED RESULTS: First, we evaluated whether density of immune cells in tumor and stroma predicted prognosis in 35 patients with disease specific survival information. We find that high number of CD3+CD8+ cells in tumor correlates with Disease Specific Survival (DSS) (p=0.0323*) and CD3+CD8+ cells in stroma may also correlate with DSS (p=0.0671). This is consistent with what is known in the literature regarding tumor infiltrating lymphocytes (TILs). We also found that CD68+ cells in stroma predict poor prognosis (0.0259*). This is consist with the proposed deleterious role for macrophages in tumor progression. Next, using nearest neighbor analysis we examined the effect of HLA-DR and Ki67 expression on spatial distribution of CD3+CD8+ T cells. We find that CD8+ T cells are closer to myeloid (CD68+) cells expressing HLA-DR. This is consistent with the potential of HLA-DR expressing cells to present antigens to T cells, and suggests that T cells may preferentially interact with HLA-DR expressing myeloid cells. Conversely, we find that Ki67 expression on tumor (SOX10+) cells correlates with increased distance from CD3+CD8+ T cells relative to SOX10+Ki67-tumor cells. This finding is consistent with the observation that more advanced tumors with higher mitotic rates have decreased T cell infiltrates, and suggests that dividing melanoma cells are less likely to interact with T cells. In addition, we performed analysis to determine whether spatial relationships defined above impact prognosis. Clinical oncology follow-up was available on 35 of the 57 patients evaluated above. We compared proximity of CD3+CD8+ cells to both myeloid (CD68+) and tumor (SOX10+) cells in patients who recurred and those with no evidence of recurrence. We found that CD3+CD8+ cells in patients who had recurrence were closer to CD68+ HLA-DR− cells than in patients who had no recurrence (t-test, p=0.0377), this correlated with DSS (p=0.003). Conversely, distance from CD3+CD8+ to CD68+ HLA-DR+ in relationship to recurrence was not significant with a trend towards CD3+CD8+ T cells being closer in nonrecurrent patients (t-test, p=0.1362). DISCUSSION/SIGNIFICANCE OF IMPACT: Consistent with the literature, we find that densities of CD8+ T cells correlates with favorable outcomes in early stage melanoma. We also find that density of CD68+ macrophages in stroma correlates with poor outcome. If proximity is a surrogate for interaction, these data indicate that dividing, Ki67+, melanoma cells interact less with CD8+ T cells than do Ki67+ melanoma cells. Further, HLA-DR expression on CD68+ infiltrating cells likely enhances their interaction with T cells. Interestingly, on further analysis, CD3+CD8+ cells were significantly closer to CD68+ HLA-DR− cells in patients who recurred, implying that interactions between these cell types may not be favorable. This analysis demonstrates that spatial analysis may be useful in predicting prognosis in early stage melanoma, and this is the first report of this type of analysis predicting outcomes in primary tumor specimens to our knowledge. Further staining and analysis of the complete patient cohort (n=120) is ongoing.
Hybrid Kentucky Bluegrass Tolerance to Preemergence and Postemergence Herbicides
- Travis C. Teuton, Christopher L. Main, John C. Sorochan, J. Scott McElroy, William E. Hart, Carl E. Sams, Thomas C. Mueller
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- Journal:
- Weed Technology / Volume 22 / Issue 2 / June 2008
- Published online by Cambridge University Press:
- 20 January 2017, pp. 240-244
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Field studies were conducted near Knoxville, TN, from 2003 to 2005 to evaluate the response of ‘Thermal Blue’, a new interspecific hybrid Kentucky bluegrass to commonly applied PRE and POST herbicides for weed management. Dithiopyr, oryzalin, oxadiazon, pendimethalin, prodiamine, quinclorac, and trifluralin applied at seeding injured hybrid bluegrass greater than 81% and reduced hybrid bluegrass cover greater than 57%. In a second study, established hybrid bluegrass was treated POST with acetolactate synthase–inhibiting herbicides including bispyribac-sodium, chlorosulfuron, foramsulfuron, halosulfuron, imazapic, imazaquin, metsulfuron, rimsulfuron, sulfosulfuron, and trifloxysulfuron at low and high rates (one and two times the suggested use rates in Kentucky bluegrass or other turfgrasses). By 5 wk after treatment (WAT), foramsulfuron at 88 g ai/ha and trifloxysulfuron at 35 g ai/ha injured hybrid bluegrass greater than 26% and reduced visually estimated quality and chlorophyll meter indices. However, hybrid bluegrass injury was no longer evident at 10 WAT. In a third study, established hybrid bluegrass was treated with clethodim, diclofop-methyl, fluazifop-p-butyl, and sethoxydim applied at low, medium, and high rates (0.5, 1, and 2 times the registered Kentucky bluegrass or other turfgrass use rates). Clethodim applied at 280 and 560 g ai/ha, fluazifop at 420 g ai/ha, and sethoxydim at 630 g ai/ha injured hybrid bluegrass 5 WAT. These treatments also reduced quality (to less than 5 on a scale of 1 to 9) and chlorophyll meter indices (24 to 37%) when compared to the untreated control. By 10 WAT, only clethodim at 560 g ai/ha caused injury (14%). By 10 WAT, hybrid bluegrass had recovered and injury was only observed in plots treated with clethodim at 560 g ai/ha. No differences in chlorophyll indices or quality were observed at 10 WAT for any POST graminicides.
Site-Specific Weed Management in Corn (Zea mays)
- Joyce Tredaway-Ducar, Gaylon D. Morgan, John B. Wilkerson, William E. Hart, Robert M. Hayes, Thomas C. Mueller
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- Journal:
- Weed Technology / Volume 17 / Issue 4 / December 2003
- Published online by Cambridge University Press:
- 20 January 2017, pp. 711-717
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Site-specific weed management can increase crop production efficiency by minimizing herbicide input costs without compromising crop yields. A reduction in herbicide inputs resulting from site-specific weed management may also decrease the probability level of nonpoint pollution compared with conventional herbicide applications. A 4.5-ha field was selected to compare site-specific and conventional weed management techniques in 1997 and 1998 at Knoxville, TN. Variable rate applications (VRAs) of atrazine preemergence (PRE) followed by dicamba postemergence (POST) were investigated for the reduction of herbicide inputs and their resulting impact on weed control and corn yield. VRAs of atrazine were on the basis of weed density data collected in 1996. VRAs of dicamba were according to common cocklebur density evaluations within the field. Compared with conventional applications, atrazine usage was decreased by 43 and 32% in the site-specific application treatments in 1997 and 1998, respectively. VRAs of dicamba reduced herbicide inputs by greater than 45% for 1997 and 1998. Corn yields were similar for the conventional and site-specific treatments in both years. On the basis of these data, site-specific herbicide applications have the greatest potential and least risk for managing weeds when POST or PRE + POST variable rate herbicide applications are used.
Effect of Venturi-Type Nozzles and Application Volume on Postemergence Herbicide Efficacy
- Robert E. Etheridge, William E. Hart, Robert M. Hayes, Thomas C. Mueller
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- Journal:
- Weed Technology / Volume 15 / Issue 1 / March 2001
- Published online by Cambridge University Press:
- 20 January 2017, pp. 75-80
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Field studies were conducted to compare venturi-type nozzles to a fan nozzle with respect to the efficacy of postemergence herbicides applied to common cocklebur and broadleaf signalgrass. Spray solutions of glufosinate, glyphosate, and paraquat were applied through all combinations of three nozzles and two application volumes. Venturi nozzles were a Delavan Raindrop Ultra (RU) and a Spraying Systems AI Teejet (AI). A Spraying Systems XR Teejet (XR) fan nozzle was included as a standard. Previous work indicated droplet size spectra differed among these nozzles. There was a difference in common cocklebur control among nozzles (AI = XR > RU), although control was at least 90% for all nozzles. Herbicide choice had a greater effect on broadleaf signalgrass control than nozzle type. Broadleaf signalgrass control differed among herbicides (glufosinate = paraquat > glyphosate) and among nozzles (AI = XR > RU). Herbicide performance varied between nozzles (AI > RU), but the AI nozzle was as effective as the XR fan nozzle.
Nitrogen Influences Bispyribac-Sodium Efficacy and Metabolism in Annual Bluegrass (Poa annua) and Creeping Bentgrass (Agrostis stolonifera)
- Patrick E. McCullough, Stephen E. Hart, Thomas Gianfagna, Fabio Chaves
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- Journal:
- Weed Technology / Volume 25 / Issue 3 / September 2011
- Published online by Cambridge University Press:
- 20 January 2017, pp. 385-390
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Field and laboratory experiments were conducted in New Jersey to investigate the influence of nitrogen on annual bluegrass and creeping bentgrass metabolism and responses to bispyribac-sodium. In field experiments, withholding nitrogen during the test period increased sensitivity of both grasses to bispyribac-sodium, and grasses fertilized biweekly had darker color on most rating dates. Nitrogen generally increased annual bluegrass tolerance to bispyribac-sodium at 74 g ha−1 but not at 148 g ha−1. Creeping bentgrass was influenced by nitrogen at both herbicide rates. In laboratory experiments, weekly nitrogen treatments increased 14C-bispyribac-sodium metabolism in both grasses compared to unfertilized plants. Annual bluegrass metabolized approximately 50% less herbicide regardless of nitrogen regime compared to creeping bentgrass. Overall, routine nitrogen fertilization appears to improve annual bluegrass and creeping bentgrass tolerance to bispyribac-sodium, which may be attributed to higher metabolism.
Bispyribac-sodium Metabolism in Annual Bluegrass, Creeping Bentgrass, and Perennial Ryegrass
- Patrick E. McCullough, Stephen E. Hart, Thomas J. Gianfagna, Fabio C. Chaves
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- Journal:
- Weed Science / Volume 57 / Issue 5 / October 2009
- Published online by Cambridge University Press:
- 20 January 2017, pp. 470-473
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Bispyribac-sodium selectively controls annual bluegrass in creeping bentgrass and perennial ryegrass, which might be attributed to differential metabolism among species. To test this hypothesis, we investigated metabolism of 14C-bispyribac-sodium in annual bluegrass, creeping bentgrass, and perennial ryegrass. Creeping bentgrass and perennial ryegrass metabolized approximately 50% of the 14C-bispyribac-sodium after 1 d, while annual bluegrass metabolized less than 20%. Parent herbicide recovered 7 d after treatment in annual bluegrass, creeping bentgrass, and perennial ryegrass was 73, 32, and 39% of total radioactivity per species, respectively. Polar metabolites recovered after 7 d in annual bluegrass, creeping bentgrass, and perennial ryegrass were 24, 59, and 55% of total radioactivity per species, respectively. Half-life of 14C-bispyribac-sodium in annual bluegrass, creeping bentgrass, and perennial ryegrass was estimated at greater than 7 d, 1 d, and 2 d, respectively. Results support the hypothesis that differential tolerances of these grasses are attributed to herbicide metabolism.
Common lambsquarters (Chenopodium album) interference with corn across the northcentral United States
- David W. Fischer, R. Gordon Harvey, Thomas T. Bauman, Sam Phillips, Stephen E. Hart, Gregg A. Johnson, James J. Kells, Philip Westra, John Lindquist
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- Journal:
- Weed Science / Volume 52 / Issue 6 / December 2004
- Published online by Cambridge University Press:
- 20 January 2017, pp. 1034-1038
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Variation in crop–weed interference relationships has been shown for a number of crop–weed mixtures and may have an important influence on weed management decision-making. Field experiments were conducted at seven locations over 2 yr to evaluate variation in common lambsquarters interference in field corn and whether a single set of model parameters could be used to estimate corn grain yield loss throughout the northcentral United States. Two coefficients (I and A) of a rectangular hyperbola were estimated for each data set using nonlinear regression analysis. The I coefficient represents corn yield loss as weed density approaches zero, and A represents maximum percent yield loss. Estimates of both coefficients varied between years at Wisconsin, and I varied between years at Michigan. When locations with similar sample variances were combined, estimates of both I and A varied. Common lambsquarters interference caused the greatest corn yield reduction in Michigan (100%) and had the least effect in Minnesota, Nebraska, and Indiana (0% yield loss). Variation in I and A parameters resulted in variation in estimates of a single-year economic threshold (0.32 to 4.17 plants m−1 of row). Results of this study fail to support the use of a common yield loss–weed density function for all locations.
Mapping Vergil's Quantitative Sublime
- Thomas E. Hart
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- Journal:
- PMLA / Publications of the Modern Language Association of America / Volume 130 / Issue 3 / May 2015
- Published online by Cambridge University Press:
- 23 October 2020, pp. 841-843
- Print publication:
- May 2015
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- By Mitchell Aboulafia, Frederick Adams, Marilyn McCord Adams, Robert M. Adams, Laird Addis, James W. Allard, David Allison, William P. Alston, Karl Ameriks, C. Anthony Anderson, David Leech Anderson, Lanier Anderson, Roger Ariew, David Armstrong, Denis G. Arnold, E. J. Ashworth, Margaret Atherton, Robin Attfield, Bruce Aune, Edward Wilson Averill, Jody Azzouni, Kent Bach, Andrew Bailey, Lynne Rudder Baker, Thomas R. Baldwin, Jon Barwise, George Bealer, William Bechtel, Lawrence C. Becker, Mark A. Bedau, Ernst Behler, José A. Benardete, Ermanno Bencivenga, Jan Berg, Michael Bergmann, Robert L. Bernasconi, Sven Bernecker, Bernard Berofsky, Rod Bertolet, Charles J. Beyer, Christian Beyer, Joseph Bien, Joseph Bien, Peg Birmingham, Ivan Boh, James Bohman, Daniel Bonevac, Laurence BonJour, William J. Bouwsma, Raymond D. Bradley, Myles Brand, Richard B. Brandt, Michael E. Bratman, Stephen E. Braude, Daniel Breazeale, Angela Breitenbach, Jason Bridges, David O. Brink, Gordon G. Brittan, Justin Broackes, Dan W. Brock, Aaron Bronfman, Jeffrey E. Brower, Bartosz Brozek, Anthony Brueckner, Jeffrey Bub, Lara Buchak, Otavio Bueno, Ann E. Bumpus, Robert W. Burch, John Burgess, Arthur W. Burks, Panayot Butchvarov, Robert E. Butts, Marina Bykova, Patrick Byrne, David Carr, Noël Carroll, Edward S. Casey, Victor Caston, Victor Caston, Albert Casullo, Robert L. Causey, Alan K. L. Chan, Ruth Chang, Deen K. Chatterjee, Andrew Chignell, Roderick M. Chisholm, Kelly J. Clark, E. J. Coffman, Robin Collins, Brian P. Copenhaver, John Corcoran, John Cottingham, Roger Crisp, Frederick J. Crosson, Antonio S. Cua, Phillip D. Cummins, Martin Curd, Adam Cureton, Andrew Cutrofello, Stephen Darwall, Paul Sheldon Davies, Wayne A. Davis, Timothy Joseph Day, Claudio de Almeida, Mario De Caro, Mario De Caro, John Deigh, C. F. Delaney, Daniel C. Dennett, Michael R. DePaul, Michael Detlefsen, Daniel Trent Devereux, Philip E. Devine, John M. Dillon, Martin C. Dillon, Robert DiSalle, Mary Domski, Alan Donagan, Paul Draper, Fred Dretske, Mircea Dumitru, Wilhelm Dupré, Gerald Dworkin, John Earman, Ellery Eells, Catherine Z. Elgin, Berent Enç, Ronald P. Endicott, Edward Erwin, John Etchemendy, C. Stephen Evans, Susan L. Feagin, Solomon Feferman, Richard Feldman, Arthur Fine, Maurice A. Finocchiaro, William FitzPatrick, Richard E. Flathman, Gvozden Flego, Richard Foley, Graeme Forbes, Rainer Forst, Malcolm R. Forster, Daniel Fouke, Patrick Francken, Samuel Freeman, Elizabeth Fricker, Miranda Fricker, Michael Friedman, Michael Fuerstein, Richard A. Fumerton, Alan Gabbey, Pieranna Garavaso, Daniel Garber, Jorge L. A. Garcia, Robert K. Garcia, Don Garrett, Philip Gasper, Gerald Gaus, Berys Gaut, Bernard Gert, Roger F. Gibson, Cody Gilmore, Carl Ginet, Alan H. Goldman, Alvin I. Goldman, Alfonso Gömez-Lobo, Lenn E. Goodman, Robert M. Gordon, Stefan Gosepath, Jorge J. E. Gracia, Daniel W. Graham, George A. Graham, Peter J. Graham, Richard E. Grandy, I. Grattan-Guinness, John Greco, Philip T. Grier, Nicholas Griffin, Nicholas Griffin, David A. Griffiths, Paul J. Griffiths, Stephen R. Grimm, Charles L. Griswold, Charles B. Guignon, Pete A. Y. Gunter, Dimitri Gutas, Gary Gutting, Paul Guyer, Kwame Gyekye, Oscar A. Haac, Raul Hakli, Raul Hakli, Michael Hallett, Edward C. Halper, Jean Hampton, R. James Hankinson, K. R. Hanley, Russell Hardin, Robert M. Harnish, William Harper, David Harrah, Kevin Hart, Ali Hasan, William Hasker, John Haugeland, Roger Hausheer, William Heald, Peter Heath, Richard Heck, John F. Heil, Vincent F. Hendricks, Stephen Hetherington, Francis Heylighen, Kathleen Marie Higgins, Risto Hilpinen, Harold T. Hodes, Joshua Hoffman, Alan Holland, Robert L. Holmes, Richard Holton, Brad W. Hooker, Terence E. Horgan, Tamara Horowitz, Paul Horwich, Vittorio Hösle, Paul Hoβfeld, Daniel Howard-Snyder, Frances Howard-Snyder, Anne Hudson, Deal W. Hudson, Carl A. Huffman, David L. Hull, Patricia Huntington, Thomas Hurka, Paul Hurley, Rosalind Hursthouse, Guillermo Hurtado, Ronald E. Hustwit, Sarah Hutton, Jonathan Jenkins Ichikawa, Harry A. Ide, David Ingram, Philip J. Ivanhoe, Alfred L. Ivry, Frank Jackson, Dale Jacquette, Joseph Jedwab, Richard Jeffrey, David Alan Johnson, Edward Johnson, Mark D. Jordan, Richard Joyce, Hwa Yol Jung, Robert Hillary Kane, Tomis Kapitan, Jacquelyn Ann K. Kegley, James A. Keller, Ralph Kennedy, Sergei Khoruzhii, Jaegwon Kim, Yersu Kim, Nathan L. King, Patricia Kitcher, Peter D. Klein, E. D. Klemke, Virginia Klenk, George L. Kline, Christian Klotz, Simo Knuuttila, Joseph J. Kockelmans, Konstantin Kolenda, Sebastian Tomasz Kołodziejczyk, Isaac Kramnick, Richard Kraut, Fred Kroon, Manfred Kuehn, Steven T. Kuhn, Henry E. Kyburg, John Lachs, Jennifer Lackey, Stephen E. Lahey, Andrea Lavazza, Thomas H. Leahey, Joo Heung Lee, Keith Lehrer, Dorothy Leland, Noah M. 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Thomasson, Katherine Thomson-Jones, Joshua C. Thurow, Vzalerie Tiberius, Terrence N. Tice, Paul Tidman, Mark C. Timmons, William Tolhurst, James E. Tomberlin, Rosemarie Tong, Lawrence Torcello, Kelly Trogdon, J. D. Trout, Robert E. Tully, Raimo Tuomela, John Turri, Martin M. Tweedale, Thomas Uebel, Jennifer Uleman, James Van Cleve, Harry van der Linden, Peter van Inwagen, Bryan W. Van Norden, René van Woudenberg, Donald Phillip Verene, Samantha Vice, Thomas Vinci, Donald Wayne Viney, Barbara Von Eckardt, Peter B. M. Vranas, Steven J. Wagner, William J. Wainwright, Paul E. Walker, Robert E. Wall, Craig Walton, Douglas Walton, Eric Watkins, Richard A. Watson, Michael V. Wedin, Rudolph H. Weingartner, Paul Weirich, Paul J. Weithman, Carl Wellman, Howard Wettstein, Samuel C. Wheeler, Stephen A. White, Jennifer Whiting, Edward R. Wierenga, Michael Williams, Fred Wilson, W. Kent Wilson, Kenneth P. Winkler, John F. Wippel, Jan Woleński, Allan B. Wolter, Nicholas P. Wolterstorff, Rega Wood, W. Jay Wood, Paul Woodruff, Alison Wylie, Gideon Yaffe, Takashi Yagisawa, Yutaka Yamamoto, Keith E. Yandell, Xiaomei Yang, Dean Zimmerman, Günter Zoller, Catherine Zuckert, Michael Zuckert, Jack A. Zupko (J.A.Z.)
- Edited by Robert Audi, University of Notre Dame, Indiana
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- Book:
- The Cambridge Dictionary of Philosophy
- Published online:
- 05 August 2015
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- 27 April 2015, pp ix-xxx
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The Theory of Tracial Von Neumann Algebras Does Not Have A Model Companion
- Isaac Goldbring, Bradd Hart, Thomas Sinclair
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- The Journal of Symbolic Logic / Volume 78 / Issue 3 / September 2013
- Published online by Cambridge University Press:
- 12 March 2014, pp. 1000-1004
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- September 2013
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In this note, we show that the theory of tracial von Neumann algebras does not have a model companion. This will follow from the fact that the theory of any locally universal, McDuff II1 factor does not have quantifier elimination. We also show how a positive solution to the Connes Embedding Problem implies that there can be no model-complete theory of II1 factors.
List of contributors
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- By Nazia M. Alam, Enrico Alleva, Hiroyuki Arakawa, Robert H. Benno, Fred G. Biddle, D. Caroline Blanchard, Robert J. Blanchard, Richard J. Bodnar, John D. Boughter, Igor Branchi, Richard E. Brown, Abel Bult-Ito, Jonathan M. Cachat, Peter R. Canavello, Francesca Cirulli, Giovanni Colacicco, John C. Crabbe, Jacqueline N. Crawley, Wim E. Crusio, Sietse F. de Boer, Ekrem Dere, Brenda A. Eales, Robert T. Gerlai, Howard K. Gershenfeld, Thomas J. Gould, Martin E. Hahn, Peter C. Hart, Andrew Holmes, Joseph P. Huston, Allan V. Kalueff, Benjamin Kest, Robert Lalonde, Sarah R. Lewis-Levy, Hans-Peter Lipp, Sheree F. Logue, Stephen C. Maxson, Jeffrey S. Mogil, Douglas A. Monks, Dennis L. Murphy, Lee Niel, Timothy P. O’Leary, Susanna Pietropaolo, Peter K.D. Pilz, Claudia F. Plappert, Bernard Possidente, Glen T. Prusky, Laura Ricceri, Heather Schellinck, Herbert Schwegler, Burton Slotnick, Frans Sluyter, Shad B. Smith, Catherine Strazielle, Douglas Wahlsten, Hans Welzl, James F. Willott, David P. Wolfer, Armin Zlomuzica
- Edited by Wim E. Crusio, Université de Bordeaux, Frans Sluyter, Robert T. Gerlai, University of Toronto, Susanna Pietropaolo, Université de Bordeaux
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- Behavioral Genetics of the Mouse
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- 05 May 2013
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- 25 April 2013, pp ix-xii
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Contributors
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- By C. Alan Anderson, Celso Arango, David B. Arciniegas, Igor Bombin, Robert W. Buchanan, C. Robert Cloninger, Joshua Cosman, C. Munro Cullum, Felipe DeBrigard, Steven L. Dubovsky, Robert Feinstein, Lynne Fenton, Christopher M. Filley, Laura A. Flashman, Morris Freedman, Oliver Freudenreich, Kimberly L. Frey, Lauren C. Frey, Kelly S. Giovanello, Deborah A. Hall, John Hart, Kenneth M. Heilman, Katherine L. Howard, Robin A. Hurley, Daniel I. Kaufer, Sita Kedia, James P. Kelly, B. K. Kleinschmidt-DeMasters, Benzi M. Kluger, David G. Lichter, Deborah M. Little, Deborah M. Lucas, Thomas W. McAllister, Mario F. Mendez, Doron Merims, Steven G. Ojemann, Fred Ovsiew, Brian D. Power, Bruce H. Price, Gila Z. Reckess, Martin L. Reite, Matthew Rizzo, Donald C. Rojas, Michael Henry Rosenbloom, Elliott D. Ross, Jeremy D. Schmahmann, Stuart A. Schneck, Jonathan M. Silver, Mark C. Spitz, Sergio E. Starkstein, Katherine H. Taber, Robert L. Trestman, Hal S. Wortzel
- Edited by David B. Arciniegas, C. Alan Anderson, Christopher M. Filley
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- Behavioral Neurology & Neuropsychiatry
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- 05 February 2013
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- 24 January 2013, pp vii-x
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Chapter Nineteen - Functional and heritable consequences of plant genotype on community composition and ecosystem processes
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- By Jennifer A. Schweitzer, Department of Ecology and Evolutionary Biology, University of Tennessee, Joseph K. Bailey, Department of Ecology and Evolutionary Biology, University of Tennessee, Dylan G. Fischer, Environmental Studies Program, The Evergreen State College, Carri J. LeRoy, Environmental Studies Program, The Evergreen State College, Thomas G. Whitham, Department of Biological Sciences, Northern Arizona University, Stephen C. Hart, School of Natural Sciences and Sierra Nevada Research Institute, University of California – Merced
- Edited by Takayuki Ohgushi, Kyoto University, Japan, Oswald Schmitz, Yale University, Connecticut, Robert D. Holt, University of Florida
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- Trait-Mediated Indirect Interactions
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- 05 February 2013
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- 06 December 2012, pp 371-390
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Summary
Introduction
Foundation species represent excellent model systems for understanding the broad consequences of variation on community and ecosystem processes as they provide a focal resource upon which associated interacting species depend. As foundation species (Dayton 1972; Ellison et al. 2005), trees and other dominant plants often create stable conditions via plant traits that allow dependent communities to assemble regularly and influence ecosystem processes such as net primary productivity (NPP) and soil fertility (i.e., nutrient cycling, via accumulations of leaf or root organic matter or root exudates; Zinke 1962; Zak et al. 1986; Binkley and Giardina 1998; Bartelt-Ryser et al. 2005; Wardle 2006). Recent studies in both terrestrial and aquatic habitats have shown that intraspecific genetic variation (defined at multiple genetic scales, including introgression [movement of genes from one species to another], genotypic diversity [studies manipulating the number of genotypes in a population] and genotypic variation [variation among genotypes]) in foundation plants can have community-wide consequences. Intraspecific variation affects associated vertebrate, arthropod and microbial community composition or activity and ecosystem level processes (recently reviewed in Johnson and Stinchcombe 2007; Hughes et al. 2008; Whitham et al. 2008; Bailey et al. 2009). For example, genetic variation resulting from the introgression of genes from one species to another through the process of hybridization has been shown to have important consequences for associated species, communities and ecosystem processes in multiple hybridizing plant species, including Salix spp., Eucalyptus spp., Quercus spp. and Populus spp. (Fritz et al. 1994; Dungey et al. 2000; Hochwender and Fritz 2004; Ito and Ozaki 2005; Wimp et al. 2005; Tovar-Sanchez and Oyama 2006; Bangert et al. 2008). In the Populus system specifically, recent field and common garden studies have shown that genetic variation across a hybridizing system (P. fremontii, P. angustifolia and their natural F1 and backcross hybrids) results in shifts in plant traits, including secondary chemistry, plant water use and above- and belowground productivity (Fischer et al. 2004; Rehill et al. 2006; Schweitzer et al. 2008a; Lojewski et al. 2009). Whether due directly or indirectly to these plant traits, rates of leaf litter decomposition, total belowground carbon (C) allocation and pools of soil nitrogen (N) and rates of net N mineralization also shift along this genetic gradient (Schweitzer et al. 2004, 2008, b; LeRoy et al. 2006; Whitham et al. 2006; Lojewski et al. 2009; Fischer et al. 2007, 2010).