Members of the alphavirus genus pose a serious or potential threat to public health in many areas of the world. Nearly all alphaviruses are maintained in nature by transmission cycles that involve alternating replication in a susceptible vertebrate and invertebrate host. The maintenance of this transmission cycle depends on the establishment of a life-long persistent infection in the invertebrate vector host. Although alphavirus replication has been extensively studied in vertebrate models, the strand-specific replication kinetics of alphaviruses during persistent infections of the invertebrate host have not been reported. We investigated the strand-specific replication of different alphavirus genotypes in invertebrate cells. By comparing different detection strategies and chemistries, we identified an optimal ssqPCR assay design for strand-specific quantification of viral RNAs in infected cells and tissues. We found that primer sets incorporating the use of a non-target tag sequence were able to avoid real-time PCR detection of amplicons that were falsely-primed during reverse-transcription. We also determined that DNA hydrolysis probes increased the sensitivity of ssqPCR assays when compared to a double-stranded DNA-specific dye, SYBR Green. Using this information, we determined the replication kinetics of two different genotypes of o'nyong nyong virus (ONNV) and chikungunya virus (CHIKV) in infected mosquito cells. We found that (-) strand viral RNAs persisted in invertebrate cells for up to 21 days after infection. We also found that significantly less (-) strand RNA was present in cells infected with opal variants of both ONNV and CHIKV than sense variants at several time points post infection, suggesting that the opal codon has a functional role in (-) strand RNA regulation. We also report the development of an ONNV replicon expression system. In total, the tools we developed for this report will facilitate future replication studies in the mosquito that may shed light on questions regarding the regulatory role of the opal codon and the persistence of (-) strand RNAs during long-term infections. The strand-specific replication kinetics of ONNV and CHIKV genotypes reported here will serve as a foundation for such investigations. / Master of Science in Life Sciences

The report details the development, pre-production, production, and post-production stages of Plus/Minus. Plus/Minus is a short, narrative film about about a young couple examining their relationship as they await the result of a pregnancy test. / text

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Writing assessments have taken two primary forms in the past two decades: direct and indirect. Irrespective of type, either form needs to be anchored to making decisions in the classroom and predicting performance on high-stakes tests, particularly in a high-stakes environment with serious consequences. In this study, 11th-grade students were given a classroom assessment in which they had 1 minute to think and 3 minutes to write. Student work was scored for correct word sequence (CWS), total words written (TWW), and correct minus incorrect word sequence (CIWS). Students were also given a high-stakes state test to determine eligibility for graduation. This study focuses on the relation between performance on the classroom assessment and the state tests, with comparisons made between the performance of students receiving special education services (SPED) and students in general education. In an age of accountability, test validity has become an increasingly complicated topic. The social consequences of assessments impact students and their educational experience.

Plant populations near the northern limits of their geographic distribution may experience different biotic pressures than southern populations. For instance, if herbivores are scarce in northern populations, performance of their host plants may benefit. In this study, I looked at populations of burdock (Arctium minus) along an 815 km latitudinal gradient from the northern range limit to more southern populations. I found that plant height, stem diameter, and number of seeds all increased on approaching the northern limit. In addition, I also found significant decreases in herbivory by generalist and specialist leaf and seed predators, even though northern plants invested less in physical and possibly chemical defenses. In an experiment in which seeds were planted in different soils, marginal soil initially produced smaller plants, but subsequently larger plants than soil from southern populations. These results indicate northern populations experience relaxed pressure from natural enemies and may benefit as a result.

Plant populations near the northern limits of their geographic distribution may experience different biotic pressures than southern populations. For instance, if herbivores are scarce in northern populations, performance of their host plants may benefit. In this study, I looked at populations of burdock (Arctium minus) along an 815 km latitudinal gradient from the northern range limit to more southern populations. I found that plant height, stem diameter, and number of seeds all increased on approaching the northern limit. In addition, I also found significant decreases in herbivory by generalist and specialist leaf and seed predators, even though northern plants invested less in physical and possibly chemical defenses. In an experiment in which seeds were planted in different soils, marginal soil initially produced smaller plants, but subsequently larger plants than soil from southern populations. These results indicate northern populations experience relaxed pressure from natural enemies and may benefit as a result.

We examined the claim that equivalence classes contain all positive elements in a reinforcement contingency by asking whether negative stimuli in a reinforcement contingency will also form an equivalence class, based on their shared function as S-minus stimuli. In Experiment 1, 5 subjects were tested for equivalence for positive and negative stimuli. Testing of positive stimuli preceded testing of negative stimuli. Two of five subjects demonstrated equivalence for positive stimuli, and three subjects demonstrated equivalence for negative stimuli. In Experiment 2, order of testing was reversed. Four of six subjects demonstrated equivalence for positive stimuli, and none demonstrated equivalence for negative stimuli. In Experiment 3, positive and negative stimuli were tested together. Only one of five subject demonstrated equivalence for positive and negative stimuli. These data suggest that negative stimuli may enter an equivalence class, and so Sidman paradigm should be expanded. Order of testing was found as a meaningful variable.

Predator cues can influence how aquatic organisms respond to anthropogenic contaminants. This study examined the effects of predator cues on behavior, metabolic rate, and sulfate (as Na2SO4) toxicity in amphipods (Gammarus minus). Predator cues included alarm cue (macerated conspecifics) and kairomone from mosquitofish (Gambusia affinis). Amphipods decreased activity and increased time in refuge when exposed to alarm cue, and increased time in refuge when exposed to kairomone. While median lethal concentrations (96-h LC50) were not influenced by predator cues, analysis of dose response curves indicated that kairomone exposure increased amphipod sensitivity to mid-range concentrations of sulfate (500-1,000 mg/L). Amphipods increased oxygen consumption in response to kairomone but not alarm cue. The influence of predator cues on contaminant lethality can be dependent on the type of cue, and physiological endpoints such as metabolic rate may help explain the basis of observed interactions.

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The ability to predict stock returns is an ability many wish to possess, and in an accurate way as possible. For many years there has been an interest in the field of factor models explaining the returns, with the aim to increase the explanatory power. This is however a complex business since the factors and their improvement of explanatory power need to be significant. Now and then, researchers come up with new significant factors that have a positive impact on models. AQR Capital Management is no exception to this, since they in 2013 presented the factor Quality Minus Junk, earning significant risk-adjusted returns. This bachelor thesis work within mathematical statistics and industrial engineering and management, aims to investigate whether or not the commercial multi-factor model used at the public pension fund Fjärde AP-fonden will be improved by adding the factor Quality Minus Junk, in the sense of explanatory power. The method used is mainly based on multiple linear regression and three three-year time periods are studied ranging from 2010 to 2018. The results from this thesis work show that the QMJ factor provides significant increases in explanatory power for one of three time periods, the most recent period 2016$-$2018. However, since the results are inconclusive further studies are needed in order to better understand how to interpret the results and whether or not to include the QMJ factor in the model. / Förmågan att förutsäga aktiers avkastning önskar många besitta, och på ett så precist sätt som möjligt. Under många år har forskning pågått inom området för faktormodeller som förklarar avkastningar, med målet att öka modellernas förklaringsgrad. Detta är dock en komplex verksamhet eftersom faktorerna och deras förbättring av förklaringsgraden måste vara signifikanta för modellen. Då och då kommer forskare fram med nya sådana faktorer som har positiv påverkan på modeller. AQR Capital Management är inget undantag eftersom de 2013 presenterade sin faktor Quality Minus Junk som visar signifikanta riskjusterade avkastningar. Detta kandidatexamensarbete inom matematisk statistik och industriell ekonomi, ämnar att utreda huruvida den kommersiella faktormodellen som används på Fjärde AP-fonden förbättras genom tillägget av faktorn Quality Minus Junk, i förklaringsgradsmening. Metoden som används är till största delen baserad på multipel linjär regression och tre treårsperioder studeras i tidsintervallet 2010 till 2018. Resultaten från detta projekt visar på att faktorn Quality Minus Junk bidrar med signifikanta ökningar av förklaringsgraden för en av tre perioder, den senaste perioden 2016-2018. Eftersom resultaten är inkonklusiva krävs vidare studier för att bättre förstå och konkludera vad dessa resultat faktiskt innebär samt för att inkludera QMJ-faktorn i modellen eller ej.