A REGIONAL BAN OF ALACHLOR AND ATRAZINE IN SOUTHEASTERN MINNESOTA: THE ECONOMIC AND ENVIRONMENTAL EFFECTS

Crop Production/Industries, Environmental Economics and Policy,

Significance of mentoring students in public schools: A literature review and naturalistic observation of academic & socio-emotional implications

Public schools today are becoming populated with increasingly diverse student bodies. These unique backgrounds include differences in race, ethnicity, culture, and socioeconomic status. While this diversity can lead to positive social outcomes, it creates an issue of achievement gaps. Challenges students may face at home can cause academic difficulties, placing some learners behind others in a classroom. With increasing class size, teachers have less ability to give one-on-one time or even slow down lessons. As a result, only a small number of students finish senior year of high school at a level that makes them prepared to enter college (Bettinger, Boatman & Long, 2013). Of course, this lack of preparedness results in multiple challenges for students. To help fill in the gaps, a growing number of entering freshman are placed into remedial or developmental courses. These classes include tutoring and mentoring, but do not provide the student with college credit. Therefore, it is very costly and timely for both the institution and the student. Earlier intervention is the solution to this major problem that schools are facing today. Mentoring programs in high schools, or even in primary education, can provide students with the one-on-one attention that they are unable to receive in the classroom. Teaching high school students organization and study skills, and providing the social support provides students with academic, social, and emotional support (Grubbs & Boes, 2009). Thus allowing high schoolers to be achieve postsecondary education success. In September 2014, Dr. Diane Kern, an Associate Professor in the University of Rhode Island’s School of Education, and a team of undergraduate students worked to create a mentoring program at South Kingstown High School- the Academic Success Academy (ASA). Because 10-17 percent of SKHS kids are living in poverty, Assistant Principal Robert Young and our team saw a need for the academic and social-emotional support that a mentoring program can provide. Over the past few months, ASA has grown in number of mentors and mentees. As an original leader of the mentoring program, it has been extremely gratifying to watch these high school students evolve and demonstrate improvements. Their personal growth, academic advancements, increased self-esteem, and development of peer relationships exhibit the success of ASA and mentoring programs overall. It has also been difficult to see the continued obstacles student face. By observing these students at ASA and reviewing literature on the strengths of mentoring, the successes of programs like ASA are unquestionable. Mentoring has the ability to help students both academically and socially. With more implementation of these programs, more students will leave high school prepared and confident in their abilities

Use of a Static Magnetic Field in Measuring the Thermal Conductivity of a Levitated Molten Droplet

Numerical models are used to analyze the complex behaviour of magnetically levitated droplets in the context of determining their thermophysical properties. We focus on a novel method reported in Tsukada et al. [4] which uses periodic laser heating to determine the thermal conductivity of an electromagnetically levitated droplet in the presence of a static DC field to suppress convection. The results obtained from the spectral-collocation based free surface code SPHINX and the commercial package COMSOL independently confirm and extend previous findings in [4]. By including the effects of turbulence and movement of the free surface SPHINX can predict the behaviour of the droplet in dynamic regimes with and without the DC magnetic field. COMSOL is used to investigate arbitrary amplitude axial translational oscillations when the spherical droplet is displaced off its equilibrium. The results demonstrate that relatively small amplitude oscillations could cause significant variation in Joule heating and redistribution of the temperature. The effect of translational oscillations on the lumped circuit inductance is analysed. When a fixed voltage drive is applied across the terminals of the levitation coil, this effect will cause the coil current to change and a correction is needed to the electromagnetic force acting on the droplet

Resonant Scattering of Surface Plasmon Polaritons by Dressed Quantum Dots

The resonant scattering of surface plasmon-polariton waves by embedded semiconductor quantum dots above the dielectric/metal interface is explored in the strong-coupling regime. In contrast to non-resonant scattering by a localized dielectric surface defect, a strong resonant peak in the scattering field spectrum is predicted and accompanied by two side valleys. The peak height depends nonlinearly on the amplitude of surface plasmon-polariton waves, reflecting the feedback dynamics from a photon-dressed electron-hole plasma inside the quantum dots. This unique behavior in the scattering field peak strength is correlated with the occurrence of a resonant dip in the absorption spectrum of surface plasmon-polariton waves due to interband photon-dressing effect. Our result on the scattering of surface plasmon-polariton waves may be experimentally observable and applied to spatially selective illumination and imaging of individual molecules.Comment: 15 pages, 3 figure

The relationship between learners' motivational schemas, learners' affect, and changes to learners' achievement goals : a test of the cognitive change of motivational beliefs model

Title from PDF of title page (University of Missouri--Columbia, viewed on March 7, 2011).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Dissertation advisor: Dr. David Jonassen.Vita.Ph. D. University of Missouri--Columbia 2010.This dissertation study was conducted to examine an original model of motivational change in hopes of addressing a paucity of research regarding changes in academic motivation (Murphy & Alexander, 2000; Pintrich, 2003; J. C. Turner & Patrick, 2008). Borrowing from conceptual change theory (Chi, 1992; Smith et. al, 1993; Dole & Sinatra, 1998), the Conceptual Change of Motivational Beliefs Model (CCMBM) posits that changes in learners' motivation can be understood by examining factors of the environment, such social agents, and factors of the individual, such as articulation of motivational schemas. For the current study, changes to learners' achievement goals for tasks and courses were examined. Three aspects of the CCMBM were assessed as they relate to these achievement goals: 1.) the relationship that motivational schema articulation has with changes in learners' achievement goals; 2.) the relationship that learners' ontological categories of the motivational schema have to changes in learners' achievement goals; and 3.) how learners' affect interacts with both the motivational schema articulation and its ontological categories in their relations to changes in learners' achievement goals. Analyses conducted using Repeated measure MANOVA and growth models via Hierarchical Linear Modeling exhibited little support for the hypothesized relationships between the CCMBM and changes to learners' achievement goals.Includes bibliographical reference

Controlling quantum-dot light absorption and emission by a surface-plasmon field

The possibility for controlling the probe-field optical gain and absorption switching and photon conversion by a surface-plasmon-polariton near field is explored for a quantum dot above the surface of a metal. In contrast to the linear response in the weak-coupling regime, the calculated spectra show an induced optical gain and a triply-split spontaneous emission peak resulting from the interference between the surface-plasmon field and the probe or self-emitted light field in such a strongly-coupled nonlinear system. Our result on the control of the mediated photon-photon interaction, very similar to the `gate' control in an optical transistor, may be experimentally observable and applied to ultra-fast intrachip/interchip optical interconnects, improvement in the performance of fiber-optic communication networks and developments of optical digital computers and quantum communications.Comment: 7 pages, 15 figure

The impact of childbirth-related post-traumatic stress on a couple's relationship: a systematic review and meta-synthesis

Objective: This review aimed to identify the impact of childbirth-related post-traumatic stress disorder (PTSD) or symptoms (PTSS) on a couple’s relationship. Background: Childbirth can be psychologically traumatic, and can lead to PTSD. There is emerging evidence that experiencing a traumatic birth can affect the quality of the couple’s relationship. This is an important issue as poor quality relationships can impact on the well-being of partners, their parenting, and the welfare of the infant. Methods: A systematic search was conducted of Amed, CENTRAL, Cinahl, Embase, Maternity and Infant Care, Medline, MITCognet, POPLINE, PsycARTICLES, PsycBITE, PsycINFO, Pubmed, and Science Direct. Additionally, grey literature, citation, and reference searches were conducted. Papers were eligible for inclusion if they reported qualitative data about parents who had experienced childbirth and measures of PTSD or PTSS and the relationship were taken. Analysis was conducted using meta-ethnography. Results: Seven studies were included in the meta-synthesis. Results showed that childbirth-related PTSD or PTSS can have a perceived impact on the couple’s relationship and five themes were identified: negative emotions; lack of understanding and support; loss of intimacy; strain on the relationship; and strengthened relationships. A model of proposed interaction between these themes is presented. Conclusions: The impact of childbirth-related PTSD or PTSS on the couple’s relationships is complex. As the quality of the couple relationship is important to family wellbeing, it is important that health care professionals are aware of the impact of experiencing psychologically traumatic childbirth as impetus for prevention and support

Obstetric near misses among women with serious mental illness: data linkage cohort study.

BACKGROUND: Investigating obstetric near misses (life-threatening obstetric complications) provides crucial information to prevent maternal mortality and morbidity. AIMS: To investigate the rate and type of obstetric near misses among women with serious mental illness (SMI). METHOD: We conducted a historical cohort study, using de-identified electronic mental health records linked with maternity data from Hospital Episode Statistics. The English Maternal Morbidity Outcome Indicator was used to identify obstetric near misses at the time of delivery in two cohorts: (1) exposed cohort - all women with a live or still birth in 2007-2016, and a history of secondary mental healthcare before delivery in south-east London (n = 13 570); (2) unexposed cohort - all women with a live or still birth in 2007-2016, resident within south-east London, with no history of mental healthcare before delivery (n = 223 274). RESULTS: The rate of obstetric near misses was 884.3/100 000 (95% CI 733.2-1057.4) maternities in the exposed group compared with 575.1/100 000 (95% CI 544.0-607.4) maternities in the unexposed group (adjusted odds ratio 1.6, 95% CI 1.3-2.0, P < 0.001). Highest risks were for acute renal failure (adjusted odds ratio 2.1, 95% CI 1.1-3.8, P = 0.022); cardiac arrest, failure or infarction (adjusted odds ratio 2.3, 95% CI 1.1-4.8, P = 0.028); and obstetric embolism (adjusted odds ratio 3.1, 95% CI 1.6-5.8, P < 0.001). CONCLUSIONS: Findings emphasise the importance of integrated physical and mental healthcare before and during pregnancy for women with SMI

Understanding corrosion features and alloy microstructural effects on fatigue initiation of corroded AA7050-T7451 using data science

Aluminum alloy 7050-T451 is generally used in aerospace structure due to its high strength-to-weight ratio and high toughness. Local galvanic coupling set up by wicking of electrolyte in between the stainless steel fastener used in the aircrafts and the aluminum substructure promote corrosion of AA7050-T7451. Fatigue crack initiation tend to occur on discontinuities in the aluminum alloy such as the corrosion damage created by the galvanic coupling. Previous study indicate that the individual metrics analyzed for the macro-scale (\u3e250 μm) corrosion features such as pit depth, pit density, pit volume, area of the pit mouth, do not fully correlate to the location of the fatigue crack initiation [1]. The objective of this study is to verify if there is an interaction effect on the metrics analyzed using the macro-scale corrosion damage features using data science techniques. Another objective of this study is to determine if the micro-scale (\u3c250 μm) corrosion features and the alloy microstructure play an important role in the fatigue initiation mechanism of AA7050-T7451. In order to understand the mechanism governing the fatigue crack formation, corrosion damage mimicking the galvanic coupling effect of AA7050-T7451 and SS316 are artificially created on the surface of AA7050-T7451. A small area on the LS surface of the fatigue specimens are exposed to different environmental conditions to create four different corrosion morphologies, namely, shallow and deep discrete pits, fissures and general corrosion with surface recession. These corrosion morphologies are characterized using the optical microscope, white light interferometer, scanning electron microscope and X-ray computed tomography. The specimens are subjected to fatigue loading using a special loading protocol that creates marker bands on the fracture surface. The specimens are cyclically loaded along the L-direction with σmax of 200 MPa, R ratio of 0.5 at a frequency of 20 Hz. The fatigue testing is done at 23°C and a controlled moist environment with \u3e90% relative humidity during the entire test. After fatigue testing, the fractographs of the specimens are obtained using the SEM. The marker bands from these fractographs are analyzed to calculate the crack growth rate and the fatigue initiation life to create a 10 μm crack from the initiation point are estimated. Data science approaches are employed to analyze the interaction effect of the individual metrics reported in the macro-scale corrosion feature analysis. Random forest and logistic regression modeling show that there is minimal significance between the macro-scale corrosion feature predictor variables and the fatigue crack initiation points. Even though data science indicate that these factors have less significance, these factors should not be neglected. The micro-scale corrosion features and the distribution of secondary phase particles as well as the grain character are individually analyzed and correlated to the location of the fatigue crack initiation for all the corrosion damage morphologies. Results show that these individual metrics does not fully dictate the location of the fatigue crack initiation. Future work of this study involves the use of data science techniques to understand the relationship between the micro-scale corrosion features, their possible interaction with the alloy microstructure, and the fatigue crack formation. This study will provide understanding on what governs the fatigue crack initiation and inform current micro-mechanical models to incorporate effects of pertinent parameters in predicting remaining life of corroded specimens. Reference: [1] Co NEC, Burns JT. Effects of macro-scale corrosion damage feature on fatigue crack initiation and fatigue behavior. Int J Fatigue 2017;103:234–47. doi:10.1016/j.ijfatigue.2017.05.028