476 research outputs found
Survival of imported fire ant species subjected to freezing and near freezing temperatures
Originally from the floodplain of the Paraguay River in South America, imported fire ants are well known pests throughout the southern United States. The black imported fire ant, Solenopsis richteri Forel, and the red imported fire ant, Solenopsis invicta Buren, are believed to have arrived in the United States through Mobile, Alabama, in ships\u27 ballast or dunnage in 1918 and the 1930s, respectively. Current federal quarantine area for fire ants covers portions of 13 states and Puerto Rico including twenty-nine counties in Tennessee.
The top northern portion of the fire ant range (northern Mississippi and Alabama, and southern Tennessee from Shelby Co. to Giles Co.) is inhabited primarily by S. richteri. The remaining range is occupied by S. invicta with the exception of a sizable band of territory between the parent species that stretches west of the Smoky Mountains to the Mississippi River, which is dominated by their hybrid. A similar pattern of species distribution occurs in their native lands in Argentina, Paraguay, Brazil, and Uruguay.
Two experimental parameters, supercooling point and survival under extended low temperature exposure, were used to examine effects of species and individual size in S. richteri, S. richteri x invicta hybrid, and S. invicta, and the effect of Thelohania solenopsae (Knell, Allen, and Hazard) infection in S. invicta on low temperature survival. Supercooling point is the lowest temperature the insect can be brought to before freezing. Based on supercooling point results for fall-collected ants, S. richteri was more cold hardy than the hybrid as shown through a significantly lower supercooling point in large- and small-sized workers. The spring-collected groups did not show this trend, and instead, the hybrid supercooled lower in the large-sized ants and there was no significant difference in the small-sized ants. Winter-collected large and small S. invicta infected with T. solenopsae supercooled to lower temperatures than those not infected. However, spring-collected colonies gave the opposite result. Large spring-collected S. richteri workers had supercooling points not significantly different from the S. invicta, but the hybrid had a significantly lower supercooling point than the parent species. Small hybrid ants were not significantly different from S. richteri, but the S. invicta supercooled to a significantly lower temperature.
In the extended exposure tests, the chilling injury of imported fire ants was measured through monitoring ant mortality during 15 days of exposure to one of three temperature regimes: +4°C, +0.5°C, and -4°C. Under the +4°C regime, both the hybrid and S. invicta infected with T. solenopsae had significantly lower mortality rates than either the S. richteri or the uninfected S. invicta by day seven. The +0.5°C regime caused increased ant mortality when compared to the +4°C regime, and the hybrids had significantly lower mortality than uninfected S. invicta from day five through the last day of exposure. The S. richteri and infected S. invicta were not significantly different. One hundred percent mortality was reached within all groups by day seven in the negative temperature regime. The uninfected S. invicta was consistently less cold tolerant than the other groups. At all three regimes, the uninfected S. invicta had the highest mortality and the hybrid had the lowest of all groups.
The supercooling point does not seem to be an appropriate measure of cold hardiness in imported fire ants. It is too easily affected by outside phenomena, such as time in the lab and thermocouple size. The differences among the supercooling points of different ant groups were not consistent and these significant differences slight, in light of natural cold weather phenomena. Furthermore, results from the extended exposure tests displayed fire ant mortality at temperatures well above their supercooling points. These results support the hypothesis that extended cold injury causes winterkill of fire ants, and may partially explain the species distribution of fire ants
Overcoming Barriers to Health and Wellbeing : Community Assets in North East Essex
The Overcoming Barriers to Health and Wellbeing report presents research carried out by Public Health and Social Science researchers at Anglia Ruskin University. Colchester Borough Council commissioned this independent study with funding from the North East Essex Health and Wellbeing Alliance.
The aim of the research is to provide Local Authorities and health and wellbeing commissioners with insight into the public health benefits of community assets from the perspective of citizens who access them in their local communities.
This report provides an evidence-based rationale for the support of community assets to improve the health and wellbeing outcomes of citizens in North East Essex. There is a focus on populations considered to be at increased risk of poor health and wellbeing outcomes, and on addressing populations in places where there are areas of comparative social deprivation in the context of growing health inequalities in the region
Impacts of transitioning from firm fixed price to fixed price incentive firm target contracts in PEO Missiles and Space
The objective of this project is to analyze the impacts to major weapon systems programs in Program Executive Office (PEO) Missiles and Space as a result of transitioning from firm fixed price (FFP) contracts to fixed price incentive firm target (FPIF) contracts. This project presents an in-depth examination of FFP and FPIF contract types, including definitions, profit mechanisms, and advantages and disadvantages associated with each type. This project reviews three iterations of Better Buying Power, with a specific focus on profitability and the use of FPIF contracts. The project presents and analyzes data collected through interviews with PEO Missiles and Space program management and contracting personnel who support programs that have transitioned from FFP to FPIF. The project also examines defense industry profitability and considers the perspective of defense contractors regarding Department of Defense profit policy. The analysis results indicate that the PEO is appropriately applying guidance for choosing FPIF contracts in follow-on production, and that there are both benefits and challenges associated with FPIF contracts. Recommendations include continuing to assess FPIF use for production programs, obtaining actual cost data, and improving incentive contracting workforce training. Further research on the longer-term effects of transitioning to FPIF is recommended.http://archive.org/details/impactsoftransit1094550587Civilian, Department of ArmyCivilian, Department of ArmyCivilian, Department of ArmyApproved for public release; distribution is unlimited
Destabilization of The Ornithine Decarboxylase mRNA Transcript by the RNA-Binding Protein Tristetraprolin
Ornithine decarboxylase (ODC) is the first and usually rate-limiting enzyme in the polyamine biosynthetic pathway. In a normal physiological state, ODC is tightly regulated. However, during neoplastic transformation, ODC expression becomes upregulated. The studies described here show that the ODC mRNA transcript is destabilized by the RNA-binding protein tristetraprolin (TTP). We show that TTP is able to bind to the ODC mRNA transcript in both non-transformed RIE-1 cells and transformed Ras12V cells. Moreover, using mouse embryonic fibroblast cell lines that are devoid of a functional TTP protein, we demonstrate that in the absence of TTP both ODC mRNA stability and ODC enzyme activity increase when compared to wild-type cells. Finally, we show that the ODC 3′ untranslated region contains cis acting destabilizing elements that are affected by, but not solely dependent on, TTP expression. Together, these data support the hypothesis that TTP plays a role in the post-transcriptional regulation of the ODC mRNA transcript
A Review and Forecast of the Onondaga County Economy
The purpose of this paper is to review the economy of Onondaga County and to offer a forecast of its future until the year 2035. This information will be used in forming a plan to improve the quality of Onondaga Lake. Understanding the past and the forecastable future is crucial to the formation of this plan and to anyone with a stake in the county’s future economic growth. To create this review and forecast, we used the REMI model, a multi-equation model of a local or regional economy and is a tool that is widely used in studies of this kind
La tempête de verglas : une occasion d’étudier les effets du stress prénatal chez l’enfant et la mère
Depuis plusieurs années, des études ont démontré que les événements stressants pendant la grossesse affectent le niveau de développement neurologique, de même que le fonctionnement cognitif et psychologique ultérieurs de l'enfant. Par exemple, Mednick (1997) a examiné l'impact d'un important séisme survenu en Chine sur le développement intellectuel et psychologique d'enfants à naître. Vingt-trois ans plus tard, des différences significatives dans le fonctionnement intellectuel, la dépression et la taille de certaines régions du cerveau ont été constatées chez ce groupe en comparaison aux enfants du groupe témoin. Des événements de moindre envergure, tels un divorce ou la perte d'emploi durant la grossesse, peuvent également augmenter l'incidence des complications obstétricales et avoir un impact sur le fonctionnement neurologique du bébé, son poids à la naissance et la circonférence de sa tête. Le décès du père ou l'exposition à un désastre naturel durant la grossesse ont été associés à la dépression, à la schizophrénie et à la criminalité à l'âge adulte. Divers effets adverses reliés aux événements stressants ont aussi été notés chez les primates. L'ensemble de ces études suggèrent que le second trimestre de la grossesse constitue une période critique pendant laquelle les événements stressants peuvent affecter le développement du foetus. Des contraintes méthodologiques nuisent actuellement à la recherche sur le stress prénatal maternel. Les études sur des animaux offrent d'excellents contrôles des environnements prénatal et postnatal. Cependant, les résultats de ces études sont difficilement applicables à l'humain à cause de la présence chez ce dernier, de nombreux facteurs de risque ou de protection absents chez les animaux. De plus, on ne peut assigner les stresseurs de façon aléatoire, dans les études sur les effets des événements de vie pendant la grossesse humaine. En effet, les traits de personnalité de la mère peuvent être transmis certes génétiquement mais également au niveau du développement. Par ailleurs, les enfants d'une mère avec de telles difficultés de personnalité sont exposés à plus d'événements de vie prénatale. D'autre part, la majorité des études sur l'humain ont une variance restreinte car il faut un très vaste échantillon de femmes enceintes pour garantir un nombre suffisant de sujets ayant vécu des événements de vie majeurs. Finalement, les études rétrospectives démontrant un lien entre un risque élevé de schizophrénie ou de dépression et des événements prénataux n'incluent pas de mesures prises sur le champ de la gravité objective ou de la manifestation biologique du stress. Nous présentons ici une revue de littérature portant sur le stress prénatal suivie d'une discussion sur comment la tempête de verglas de 1998 pourrait être utilisée pour faire la lumière sur des questions telles que les mécanismes par lesquels le stress prénatal exerce une influence sur la santé mentale du foetus.Over the last several years, studies have shown that stressful experiences during the pregnancy can predict levels of neurological development, as well as cognitive and psychological functioning, during childhood and adulthood. For example, Mednick (1997) has been studying the effects of a major earthquake in China on the psychological and intellectual development of the unborn child. Twenty-three years after the quake, significant differences have been found between the earthquake group and a control group born one year later in terms of intellectual functioning, depression, and the size of certain brain regions. Less severe events, such as a divorce or job loss during the pregnancy, may also increase the risk of obstetric complications and may have an effect on the baby's neurological well being, weight and head circumference at birth. Death of the baby's father during the pregnancy and natural disasters have both been associated with increased rates of depression, schizophrenia and criminality in adulthood. Several of these same effects have been found in studies of prenatal stress in non-human primates. Many of these studies suggest that the second trimester of pregnancy is a particularly critical period during which stressful events may compromise development of the fetus. Methodological constraints limit research on prenatal maternal stress. Animal studies are able to control for pre- and postnatal environments. However, animal studies have limited generalizability to humans for whom numerous risk and protective factors are in operation. Studies of human pregnancies cannot randomly assign subjects to stress conditions. Maternal personality and temperament may be associated with characteristics of a woman's child not only through genetic transmission of personality, but possibly also through differential exposure to difficult life conditions which may, in part, be self-imposed. In addition, studies of prenatal life events in humans have severely restricted variance; very large samples of women must be screened to identify even small numbers of women who have experienced major life events during the pregnancy. Finally, follow-back studies which show an association between prenatal events and later rates of mental illness, do not include timely evaluations of actual rates of exposure to the event, nor the pregnant woman's subjective or biological reactions to the event. In this paper, we present a review of the literature on prenatal maternal stress followed by a discussion of how the January 1998 Québec ice storm could be used to study the mechanisms by which prenatal stress may influence mental health outcomes in the unborn child.Desde hace varios años, estudios han demostrado que los hechos estresantes durante el embarazo afectan el grado de desarrollo neurológico, como posteriormente el funcionamiento cognoscitivo y psicológico del niño. Por ejemplo, Mednick (1997) examinó el impacto de un terremoto importante occurrido en China en el desarrollo intelectual y psicológico del futuro niño. Veintitres años después, diferencias significativas fueron constatadas en en funcionamiento intelectual, la depresión y la dimensión de ciertas regiones del cerebro en este grupo, comparativamente a un grupo testigo. Hechos de menor envergadura como el divorcio o la pérdida del empleo durante el embarazo pueden igualmente aumentar la incidencia de las complicaciones obstétricas y tener un impacto en el funcionamiento neurológico del bebé, su peso en el nacimiento y la circunferencia de la cabeza. La muerte del padre o la exposición a un desastre natural durante el embarazo han sido asociados a la depresión, la esquizofrenia y la criminalidad en la edad adulta. Diversos efectos adversos ligados a hechos estresantes también han sido notados en los primates. El conjunto de estos estudios sugieren que el segundo trimestre del embarazo constituye un período crítico durante el cual los eventos estresantes pueden afectar el desarrollo del feto. Impedimentos metodológicos afectan actualmente la investigación sobre el estrés perinatal materno. Los estudios con animales ofrecen excelentes controles del medio perinatal y postnatal. Sin embargo los resultados de estos estudios dificilmente son aplicables al ser humano a causa de la presencia de numerosos factores de riesgo o de protección, ausentes en los animales. Además, en los estudios sobre los efectos de los eventos de vida durante el embarazo no se puede asignar estresores de forma aleatoria. En efecto, los rasgos de personalidad de la madre pueden ser transmitidos genéticamante, pero también en el curso del desarrollo. Entre otras, los niños de una madre con determinadas dificultades de personalidad están expuestos a más hechos perinatales de vida. Por otra parte, la mayoría de los estudios sobre el humano varían poco puesto que se necesita un amplio muestreo de mujeres embarazadas que garantice un número suficiente de sujetos que hayan vivido eventos de vida mayores. Para terminar, los estudios retrospectivos demuestran una relación entre el alto riesgo de esquizofrenia o de depresión y los hechos perinatales no incluyen la toma rápida de medidas sobre la gravedad objetiva o sobre la manifestación biológica del estres. Nosotros presentamos aquí una revista de la literatura que aborda el estres perinatal, seguida de una discusión sobre cómo la tempestad de hielo de 1998 podría se utilizada para aclarar sobre interrogantes tales los mecanismos por los cuales el estres perinatal ejerce una influencia en la salud mental de feto
Prospective Teachers\u27 Use of Representations in Solving Statistical Tasks with Dynamic Statistical Software
This study examined a random stratified sample (n=62) of prospective teachers\u27 work across eight institutions on three tasks that utilized dynamic statistical software. Our work was guided by considering how teachers may utilize their statistical knowledge and technological statistical knowledge to engage in cycles of investigation. Although teachers did not tend to take full advantage of dynamic linking capabilities, they utilized a large variety of graphical representations and often added statistical measures or other augmentations to graphs as part of their analysis
“It Hurts a Latina When They Tell Us Anything About Our Children”: Implications of Mexican-Origin Mothers' Maternal Identities, Aspirations, and Attitudes About Cultural Transmission for Childhood Obesity Prevention
Background: This qualitative study explored values, attitudes, and beliefs held by Mexican-origin mothers of preschool-aged children to enhance understanding of cultural influences on behaviors associated with childhood obesity risk. Methods: During face-to-face interviews, 39 Mexican-origin mothers of preschool-aged children discussed their hopes for their children, their image of the perfect mother, Mexican and American foods, why they taught their children about these foods, and their opinions about television (TV) viewing language. Results: Participants wanted their children to become successful, ?good? people, which necessitated doing well in school. Mothers also wanted their children to know them, which required understanding the mothers' Mexican backgrounds. Mothers wanted their children to maintain Mexican values and identities. Some mothers viewed American culture as harmful. Many participants prepared their child for going to Mexico by exposing them to Mexican culture and foods. Some mothers fed their children American foods to prepare them for school. Perceptions of American foods generally reflected stereotypical unhealthy foods. TV helped teach children Spanish and English. Being a good mother was core to participants' identities; thus, hearing about child overweight made some mothers feel like failures. Conclusions: Health promotion programs may be more salient to mothers if they: underscore how a healthy weight can help children in school; teach mothers to prepare healthy American foods that their children will encounter in kindergarten; assist mothers in teaching their children about Mexico; and present information about childhood obesity in ways that reinforce what mothers are doing well, enhance mothers' self-efficacy, and allay feelings of failure.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140339/1/chi.2015.0011.pd
Toward a sustainable culture of peer partnership
This project is a two phase design working in partnership with five universities to develop, implement and systematically embed a distributive leadership model that aims to embed peer partnership (review, development) within the culture of teaching and learning excellence. This presentation will posit a ‘prototype’ peer review leadership model based on ongoing research that brings together both the fundamentals of peer review with the broader importance of context and persons. It will be argued that essential to teaching development is a need to address not only the implementation of peer partnership programs but also strategies to influence and change both the contexts of teaching and the advantages for colleagues. Peer review as a strategy to develop excellence in teaching needs to be considered from a holistic perspective encompassing all elements of the teaching environment. The emphasis is on working to foster the type of conditions needed for leadership and change to begin and be sustained. The work has implications for policy, research, leadership development and student outcomes and has potential application world-wide. Phase 1 has collected focus interview and questionnaire data to inform the research and is being analysed using a thematic qualitative approach and statistical analysis. Evidence is emerging currently as the project is ongoing
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