3,479 research outputs found
Agricultural Land Use, Watershed Characteristics, and Hydrological Forces Contributing to the Impairment of a Shallow Lake in the Western Corn Belt Ecoregion
The Lake Titlow watershed (approximately 35,000 acres) in south-central Minnesota is part of the Minnesota River Basin. The lake is listed in the draft 2010 Clean Water Act Section 303d for nutrient pollution, eutrophication, and biological indicators for impairment of aquatic life and recreational use. Over 90 percent of pre-settlement wetlands are currently drained for agricultural land use. The Lake Titlow watershed is over 80 percent row crops and land use is implicated as a primary cause of impairment in the lake.
Water samples were collected from the Lake Titlow tributaries McLeod-Sibley Judicial Ditch Number 18 (JD18), Sibley County Ditch Number 18 (CD18), and Ditch 250 (D250) during 2009 and 2010 and were analyzed for total suspended solids (TSS), total phosphorus (TP), and nitrate-nitrite nitrogen (NOx). Investigative methods included continuous recording stream stage and through the use of rating curves, discharge. Runoff, sediment loads, and nutrient loads were then determined from the field data. Four rain gauges collected precipitation each year and were used to assess the impact of precipitation on runoff and loading. Four characteristic precipitation events were selected for each of the calendar years 2009 and 2010 to estimate the loads of sediment and nutrients to the lake and more fully understand the specific roles that land use, hydrologic soil group, slope, and precipitation play with regard to causing sediment and nutrient loading in the lake.
Results indicate runoff and loads are significant and highly variable by position within the watershed, areas referred to herein as subsheds. The row crop land use, soils characteristics, and precipitation do contribute to overall runoff and loads; however, they do not control subshed variability. Although the low-sloping land surfaces of the watershed should not contribute to overall runoff and loads, results indicate that subtle slope changes in the JD18Lo and CD18Lo subsheds could contribute to the variability of loads seen in these portions of the watershed.
The location and type of best management practices to implement is debatable because the results of this study indicate that large runoffs and loads could originate within any given subshed during any given rainstorm event. This study was unable to precisely identify the root cause of the variability in subshed runoff and loading. Therefore, it is suggested to look at other factors (e.g., antecedent soil moisture, rainfall intensity, mass wasting, etc.) to explain the subshed variability in the sediment and nutrient loading in future studies of this lakeshed
Perceived partner similarity of desired intimacy in heterosexual relationships
2011 Summer.Includes bibliographical references.Past literature has discussed gender differences in romantic partners' desires for intimacy and has suggested that these gender differences have negative effects on heterosexual relationships. The current study sought to explore the validity of these claims. Participants completed surveys assessing their own desires for intimacy, their perceptions of their partners' desires for intimacy, and relationship outcome variables (satisfaction/commitment). Results indicated that perceived similarity of overall desired intimacy to one's partner is associated with relationship satisfaction and commitment. The effects of perceived similarity varied across types of intimacy and gender, such that perceived similarity in desires for social and emotional intimacy were most associated with relationship outcome variables for women and perceived similarity in desires for sexual intimacy was most associated with relationship outcome variables for men
Discussion Boards in the Online Classroom: Are They Actually Influencing Instructor Mediated Immediacy, Student Motivation, Student Affective Learning, Student Connectedness, and Online Learning Climate?
Discussion boards are one of the most popular forms of asynchronous discussion in online classes. Utilized by instructors in asynchronous and synchronous courses to facilitate class discussions, they offer a means for the class to communicate among each other and with the instructor. Few researchers have examined how the use of discussion boards in the online classroom affects instructor mediated immediacy, student motivation, affective learning, connectedness, and the online learning climate. This study sought to examine the influence of discussion boards on these variables. After review of research on discussion boards and related variables, participants completed a questionnaire composed of closed- and open-ended questions. Students currently enrolled in an asynchronous or synchronous, online class which utilized asynchronous discussion boards completed the survey to determine their perceptions of how discussion boards affected their learning and connection in the course. A multivariate ANOVA test found differences occurring between the discussion boards optional condition (M = 70.75, SD = 20.72) and both the no discussion boards condition (M = 87.38, SD = 20.12) and the required, graded discussion boards condition (M = 84.72, SD = 18.96) for motivation. A thematic analysis revealed consistent themes for all other dependent variables. Participants utilized discussion boards most commonly only if it were for a grade and felt discussion boards did not bring them closer to their instructor. Discussion boards were seen as a place for student-to-student conversation, but they did not bring students closer on a personal level or contribute to the online learning climate positively
Comprendre la participation des superviseurs en médecine familiale communautaire au scholarship de l’éducation : perceptions, facteurs d'influence et pistes d'action prometteuses
Background: Residency training is increasingly occurring in community settings. The opportunity for community-based scholarship is untapped and substantial. We explored Community Family Medicine Preceptors’ understanding of Educational Scholarship (ES), looked at barriers and enablers to ES, and identified opportunities to promote the growth of ES in this setting.
Methods: We conducted semi-structured interviews with fifteen purposively chosen community-based Family Medicine preceptors in a distributed Canadian family medicine program.
Results: Community Family Medicine Preceptors strongly self-identify as clinical teachers. They are not well acquainted with the definition of ES, but recognize themselves as scholars. Community Family Medicine Preceptors recognize ES has significant value to themselves, their patients, communities, and learners. Most Community Family Medicine Preceptors were interested and willing to invest in ES, but lack of time and scarcity of primary care research experience were seen as barriers. Research process support and a connection to the academic center were considered enablers. Opportunities to promote the growth of ES include recognition that there are fundamental differences between community and academic sites, the development of a mentorship program, and a process to encourage engagement.
Conclusions: Community Family Medicine Preceptors identify foremost as clinician teachers. They are engaged in and recognize the value of ES to their professional community at large and to their patients and learners. There is a growing commitment to the development of ES in the communityContexte : Les stages de résidence se font de plus en plus en milieu communautaire, un milieu qui offre des possibilités de scholarship intéressantes demeurant inexploitées. Nous avons étudié la compréhension qu’ont les superviseurs en médecine familiale communautaire au sujet du scholarship de l’éducation (SÉ), examiné les obstacles et les facteurs favorables au SÉ et identifié les possibilités de le promouvoir dans le cadre communautaire.
Méthodes : Nous avons mené des entretiens semi-structurés avec quinze cliniciens enseignants en médecine familiale communautaire choisis à dessein dans un programme de médecine familiale décentralisée au Canada.
Résultats : Les superviseurs en médecine familiale communautaire se définissent fermement comme cliniciens enseigants. Peu familiers avec la définition du SÉ, ils se considèrent néanmoins comme érudits. Ils reconnaissent l’importance considérable du scholarship de l’éducation autant pour eux que pour leurs patients, les communautés et les apprenants. La plupart des superviseurs en médecine familiale communautaire se disent intéressés et disposés à s’investir en SÉ, mais se sentent limités par le manque de temps et le peu d'expérience en recherche en soins primaires. Le soutien au processus de recherche et un lien avec le centre universitaire sont considérés comme éléments favorables. La possibilité de développer le SÉ passe par la reconnaissance des différences fondamentales entre les sites communautaires et universitaires, la création d'un programme de mentorat et la mise en place d’un processus visant à encourager l'engagement.
Conclusions : Les superviseurs en médecine familiale communautaire se définissent avant tout comme des cliniciens enseignants. Ils s’investissent dans le SÉ et ils reconnaissent son importance pour leur communauté professionnelle, leurs patients et leurs apprenants. Il y a un engagement croissant envers le développement du SÉ dans la communauté
Longitudinal Effects of School Climate on Middle-School Students\u27 Academic, Social-Emotional and Behavioral Outcomes
Millions of youth are at risk for low academic achievement, school dropout, risky behavior, bullying, and mental health concerns, especially those living in rural areas. Protective factors can reduce the likelihood of children and adolescents experiencing these negative outcomes. Research shows that positive school climate is a powerful protective factor for youth. The present study investigated the longitudinal relations between middle school students\u27 school climate perceptions and their academic, social-emotional, and behavioral development over two years. Specifically, 510 students in grades 5-9 from six rural schools rated their support and influence at school as well as their internalizing problems, personal adjustment, and risky behavior. Students\u27 academic performance was progress monitored using reading and math curriculum-based measures. Data were examined using Hierarchical Linear Modeling (HLM). Results revealed significant relations between students\u27 perceived school climate and their social-emotional, behavioral, and mathematics outcomes over time. Further, school climate was a predictor of students\u27 future involvement in risky behavior. There was a slight negative trend in students\u27 perceived school climate as well as increases in their social-emotional problems and risky behavior, which suggests the need to implement evidence-based school climate improvement strategies aligned to students\u27 developmental levels. Findings indicate the importance of incorporating school climate assessment and improvement strategies in school practices and policies to enhance student outcomes and school contexts. Limitations and future directions for research are discussed based on results from the present study and the school climate literature. Overall, school climate significantly influences outcomes for yout
Remembering Dr. Benita Cohen: A tribute to a life well-lived
To honor the legacy of Dr. Benita Cohen, this special volume of Witness: The Canadian Journal of Critical Nursing Discourses is dedicated in remembrance of her. This Invited Commentary reflects on Benita’s career, passions, personality and key contributions to public health and nursing. Dr. Cohen was an exceptional nurse, researcher, educator, mentor, and health policy consultant. Her vision has shaped the fields of public health and community health nursing, and her impact will be felt for many generations to come.
Type 2 polysaccharide storage myopathy in Quarter Horses is a novel glycogen storage disease causing exertional rhabdomyolysis
Background: Both type 1 (PSSM1) and type 2 polysaccharide storage myopathy (PSSM2) are characterised by aggregates of abnormal polysaccharide in skeletal muscle. Whereas the genetic basis for PSSM1 is known (R309H GYS1), the cause of PSSM2 in Quarter Horses (PSSM2-QH) is unknown and glycogen concentrations not defined.
Objectives: To characterise the histopathological and biochemical features of PSSM2-QH and determine if an associated monogenic variant exists in genes known to cause glycogenosis.
Study design: Retrospective case control.
Methods: Sixty-four PSSM2-QH, 30 PSSM1-QH and 185 control-QH were identified from a biopsy repository and clinical data, histopathology scores (0–3), glycogen concentrations and selected glycolytic enzyme activities compared. Coding sequences of 12 genes associated with muscle glycogenoses were identified from whole genome sequences and compared between seven PSSM2-QH and five control-QH.
Results: Exertional rhabdomyolysis in PSSM2-QH occurred predominantly in barrel racing and working cow/roping performance types and improved with regular exercise and a low starch/fat-supplemented diet. Histopathological scores, including the amount of amylase-resistant polysaccharide (PSSM2-QH 1.4 ± 0.6, PSSM1-QH 2.1 ± 0.3, control-QH 0 ± 0, p \u3c 0.001), and glycogen concentrations (PSSM2-QH 129 ± 62, PSSM1-QH 175 ± 9, control-QH 80 ± 27 mmol/kg, p \u3c 0.0001) were intermediate in PSSM2-QH with significant differences among groups. In PSSM2-QH, abnormal polysaccharide had a less filamentous ultrastructure than PSSM1-QH and phosphorylase and phosphofructokinase activities were normal. Seventeen of 30 PSSM2-QH with available pedigrees descended from one of three stallions within four generations. Of the 29 predicted high or moderate impact genetic variants identified in candidate genes, none were present in only PSSM2-QH and absent in control-QH
High-Intensity and High-Brightness Source of Moderated Positrons Using a Brilliant gamma Beam
Presently large efforts are conducted towards the development of highly
brilliant gamma beams via Compton back scattering of photons from a
high-brilliance electron beam, either on the basis of a normal-conducting
electron linac or a (superconducting) Energy Recovery Linac (ERL). Particularly
ERL's provide an extremely brilliant electron beam, thus enabling to generate
highest-quality gamma beams. A 2.5 MeV gamma beam with an envisaged intensity
of 10^15 s^-1, as ultimately envisaged for an ERL-based gamma-beam facility,
narrow band width (10^-3), and extremely low emittance (10^-4 mm^2 mrad^2)
offers the possibility to produce a high-intensity bright polarized positron
beam. Pair production in a face-on irradiated W converter foil (200 micron
thick, 10 mm long) would lead to the emission of 2 x 10^13 (fast) positrons per
second, which is four orders of magnitude higher compared to strong radioactive
^22Na sources conventionally used in the laboratory.Using a stack of converter
foils and subsequent positron moderation, a high-intensity low-energy beam of
moderated positrons can be produced. Two different source setups are presented:
a high-brightness positron beam with a diameter as low as 0.2 mm, and a
high-intensity beam of 3 x 10^11 moderated positrons per second. Hence,
profiting from an improved moderation efficiency, the envisaged positron
intensity would exceed that of present high-intensity positron sources by a
factor of 100.Comment: 9 pages, 3 figure
Nontarget Effects of the Mosquito Adulticide Pyrethrin Applied Aerially During a West Nile Virus Outbreak in an Urban California Environment
In August 2006, a pyrethrin insecticide synergized with piperonyl butoxide (EverGreen Crop Protection EC 60-6, McLaughlin Gormley King Company, Golden Valley, MN) was sprayed in ultralow volumes over the city of Davis, CA, by the Sacramento-Yolo Mosquito and Vector Control District to control mosquitoes transmitting West Nile virus. Concurrently, we evaluated the impact of the insecticide on nontarget arthropods by 1) comparing mortality of treatment and control groups of sentinel arthropods, and 2) measuring the diversity and abundance of dead arthropods found on treatment and control tarps placed on the ground. We found no effect of spraying on nontarget sentinel species including dragonflies (Sympetrum corruptum), spiders (Argiope aurantia), butterflies (Colias eurytheme), and honeybees (Apis mellifera). In contrast, significantly higher diversity and numbers of nontarget arthropods were found on ground tarps placed in sprayed versus unsprayed areas. All of the dead nontarget species were small-bodied arthropods as opposed to the large-bodied sentinels that were not affected. The mortality of sentinel mosquitoes placed at the same sites as the nontarget sentinels and ground tarps ranged from 0% to 100%. Dead mosquitoes were not found on the ground tarps. We conclude that aerial spraying with pyrethrins had no impact on the large-bodied arthropods placed in the spray zone, but did have a measurable impact on a wide range of small-bodied organisms
Positron Annihilation Spectroscopy Study of Interfacial Defects Formed by Dissolution of Aluminum in Aqueous Sodium Hydroxide
- …