Active learning generally increases student achievement, but not all instructors experience the same magnitude of gains. This variation in student achievement is likely due to differences in how active learning is implemented in the classroom as well as differences in total classroom time devoted to active learning. Although multiple tools exist for characterizing active learning in the classroom, none have been used to explain variation in student achievement. We are developing a new type of Classroom Observation Tool (COT) that characterizes how closely an instructor’s use of active learning matches the best practices suggested in education literature and can be correlated with observed variation in student exam achievement. Currently, we are using the COT to analyze 3 randomly selected classroom sessions from 27 different introductory biology instructors using archived footage. We will create a linear model that combines instructor’s COT scores with controls for variability in student ability and exam challenge between instructors to predict student exam performance. This model will allow us to identify which elements measured by the COT are most strongly correlated with variation in student performance. With this baseline data, we will be able to recommend the use of the COT to help Faculty assess the effectiveness of their instruction, thereby enhancing teaching and student learning not only within Biology education at UW, but also across all postsecondary education.

This research analyzes interviews and census data to explore the varying ethical perceptions of water use in Oman. For many populations living in the hyper-arid Arabian Peninsula, cultural and religious values have always required that people strictly limit their water use. Today after one generation of intense urbanization, Omanis still maintain these values of conservation, however they have also come to glorify water-intensive, urban lifestyles. Given this apparent contradiction, why has “development” been able to frame urban water use so positively, while contradictory perceptions of ethical water use remain intact? I argue that people do not change their water usage based on actual scarcity or ability to consume, but rather based on the symbolism that their surrounding community attaches to their resource use. In urban and rural Oman competing symbols have been introduced that support two very different water ethics. To reduce cognitive dissonance, Omanis compartmentalize each ethic in relation to different community settings and go through a process of switching their ethical codes when traveling between the countryside and urban centers. For much of the Middle East and other regions around the world, water scarcity is increasing dramatically, while urbanization and population expansion has produced increasing demand. Understanding how peoples’ perceptions of water are formed will be essential for policymakers as many regions of the world are beginning to face extreme water shortages and related socio-economic crises.

Emma B. Andrews' diaries give insight into the lives of archeologists working in Egypt’s Valley of the Kings at the turn of the last century. Due to her association with the archeologist Theodore Davis, Andrews had a unique opportunity to see the excavations in the Valley of the Kings firsthand during her travels between 1889 and 1913. Though these diaries provide valuable cultural, social and archeological perspectives on this period of Egyptian history, they have gone largely unnoticed by the academic community, and this project intends to make these works available as invaluable for academia. In order to bridge a gap in the publishing world, the NEH-funded Newbook Digital Texts project provides a unique environment for the multi-media publication of texts, transcriptions, translations, and annotation of works that are not compatible with traditional publishing or available large-project digital platforms. Newbook Digital Texts’ collaborative nature enables individual projects to inexpensively adapt to the project, providing opportunities for individuals to publish academic works with less expense and hassle. It also enables people to access important texts and resources more easily. As undergraduate researchers, we have the opportunity to work with these primary texts, learning useful digital humanities skills. At the beginning of the process, we learned how to create a structured transcription, allowing us to auto-tag the text. During this process, we have been able to complete a structural analysis of the text. We all worked with XML formatting, creating name lists, and doing content tagging within the text. Additionally, we completed independent research for inclusion in the project’s Wikipedia. Upon reading through the diaries and editing them, our project recognized important links to other excavators and research done in the Valley of the Kings, and we believe the diaries will fill gaps within academia in this field.

The successful growth of a plant is dependent on many variables, such as location, extent of available resources, competition by other plants, and reproductive success; what if there was a way a plant could almost guarantee survival and success? Many invasive species have found ways to be very successful; Alliaria petiolata (garlic mustard) has developed allelopathy, which can decrease surrounding plants germination rates and ability to grow. In my experiment I will attempt to determine if different populations of garlic mustard have variations in allelopathic strength. At least ten samples of garlic mustard from three different locations throughout Seattle will be grown, along with ten control lettuce plants. The three sites for this experiment are Seola Park, Woodland Park, and the University of Washington. Throughout the experiment I will try to figure out if the lettuce seeds germination rate and growth abilities are affected as a result of the garlic mustard. I will plant lettuce seeds in with garlic mustard and analyze the germination rates compared to the control samples, and at the end of my experiment I will harvest the lettuce and garlic mustard samples, and they will be biomassed. The data collected will be analyzed for significant results. My hypothesis for this experiment is that the sites in which the garlic mustard has been present the longest will have the greatest negative effect on the lettuce plants; but, because I don't know how long each population has been established I believe the Seola Park location, because it had the largest garlic mustard population, will have the largest effect on the lettuce.

Speciation is the process by which one species becomes two species that can no longer interbreed. A common hypothesis is that infertility between closely related species is due to the rapid evolution of DNA double-strand-break (DSB) hotspots that are active in meiosis. DNA DSBs play an important role in meiosis by initiating recombination after chromosome replication and can be repaired as crossovers. During DNA DSB repair, the broken strand of a homologue invades and repairs its break with the strand of the aligned homologue by matching complementary nucleotides. The repair can result in a heteroduplex which refers to a mismatch, such as adenine paired with cytosine. Heteroduplex rejection occurs when the cell’s recombination machinery rejects recombination at sites where heteroduplex forms, and it is known to require the msh2 gene. We hypothesize that heteroduplex rejection inhibits DSB repair in interspecies hybrids and can result in infertility and thereby the isolation of species. Schizosaccharomyces kambucha and Schizosaccharomyces pombe are two very closely related fission yeast species that are 99.5% identical at the DNA sequence level. Despite their similar genetic makeup, we found that their hybrids show decreased fertility and decreased recombination frequencies. We are testing whether inhibiting heteroduplex rejection will increase the fertility and recombination rates of the fission yeast hybrids. For this experiment, we have created msh2Δ Schizosaccharomyces pombe and Schizosaccharomyces kambucha mutants that cannot do heteroduplex rejection so the cells should go through DNA DSB repair even if there are mismatches. We expect to see an increase in fertility and recombination in the msh2Δ hybrids. This research may be extended further to explain speciation in other organisms or unexplained infertility between human couples.

One of the most vital roles of mitochondria is to provide the cell with energy through oxidative phosphorylation (OXPHOS). Mutations within the mitochondrial DNA (mtDNA) can affect gene products that function in OXPHOS. While maternally inherited mtDNA mutations often affect the nervous system and musculature, and somatic mtDNA mutations are associated with aging and age related diseases, the cellular mechanisms that influence the frequency of mtDNA mutations are poorly understood. We are using the fruit fly Drosophila to address this matter because our recent work indicates that the mtDNA mutational patterns in flies share many features with vertebrates, including a similar somatic mtDNA mutation frequency, a prevalence of transition mutations, and an accumulation of mutations with age. A high prevalence of mtDNA mutations can lead to dysfunctional mitochondria, and previous work in Drosophila has shown that a mitochondrial quality control mechanism exists to degrade dysfunctional mitochondria. Although it is clear that this mitochondrial quality control mechanism can detect and degrade damaged mitochondria, whether it can influence the mtDNA mutation frequency by detecting and degrading mitochondria with a mtDNA mutation is unknown. To address this matter we will use a high-fidelity Duplex Sequencing approach to detect rare mtDNA variants. Genetic manipulations in mitochondrial quality control factors will be used to probe their effect on mtDNA mutation frequency. We predict that loss of these quality control factors will cause an increase in mtDNA mutations and that overexpression of these factors will cause a decrease in mtDNA mutations. The results from these studies will lead to improved understanding about factors that influence mtDNA mutation frequency and also diseases caused by mtDNA mutations.

Autism Spectrum Disorder (ASD) is characterized by deficits in communication, social skills, and repetitive behaviors. Understanding the risk factors in early childhood that lead to the diagnosis of autism is an important area of research. Specifically, researchers are trying to understand how communication development differs in children who go on to develop autism in comparison to those that do not. Previous research has shown that 18.7% of infants, who have at least one older sibling with ASD, develop autism. In this current study, two groups of infants between the ages of six and twenty-four months were tracked longitudinally: high-risk infants who have an older sibling with ASD and low risk infants who have no family history of ASD. The Communication and Symbolic Behavior Scales (CSBS) protocol was used to identify various communication modes used by each infant at 12 and 18 months of age. The videotaped interactions between the infant, clinician, and parent were coded offline by a group of trained undergraduates. The following communicative acts were defined and coded: (1) behavior regulation: the infant’s attempt to control some behavior of an individual around him/her; (2): social interaction: the infant’s ability to bring attention to him/herself; and (3) joint attention: the infant’s ability to bring attention to an object. Our aim is to explore differences between rates of communicative acts in high risk and low risk infants at 12 months of age. Previous research suggests that children with ASD are less likely to draw the attention of others to objects or events. We hypothesize that high risk infants will display significantly lower rates of communication acts in all three domains when compared to their low risk peers. This study will contribute to a better understanding of possible deficits in early communication in this high-risk population, leading to earlier intervention opportunities.

Autism Spectrum Disorders (ASD) are characterized by atypical social development, decreased verbal and non-verbal communication, and repetitive behaviors. Retrospective studies of children with autism suggest an association between pregnant mothers’ use of certain medications and the occurrence of ASD diagnoses in their children. Other findings have also determined a relationship between an infant’s cognitive development and maternal mental health. In addition to maternal variables influencing development, infants may be at genetic risk based on sibling status: specifically, infants with siblings who have been diagnosed with ASD are at high-risk for also developing ASD. Using data from the Early Connections study – a longitudinal study of high-risk infant siblings compared to low-risk infants, we examined whether maternal variables resulted in added risk for poor child outcomes in the high-risk group. Information about family history of medical and psychiatric diagnoses, mother’s medication use during pregnancy, pregnancy complications, and other details pertaining to the mother’s delivery history were compiled for three groups: infants who develop autism (high risk, n=13, low risk, n=1); high risk infants who do not develop autism (n=32); and low risk infants who do not develop autism (n=42). Data analysis is ongoing. This study will examine the role of prenatal and postnatal effects in infant development in a high-risk sample. It is expected that mothers of high-risk infants will exhibit more medical and psychiatric conditions.The results of this study could aid in medical care for families who have a child with autism and are considering care options during a later pregnancy.

We  present an extension of the Astronomy Department’s curriculum for visually impaired junior high  school students. Our lesson plans are a complementary addition to  Noreen Grice's Braille and large print  readings. These lessons satisfy the Washington State Essential Academic Learning Requirements (EALR's) for junior high school students, the level at which students are introduced to astronomy. We  present here a sample of new material that covers the composition, formation and evolution of the Sun.   Our lessons include activities, audio tracks, 3D models, and online links to advanced topics. We outline additional curricula that we are actively  developing, such as biographies of visually impaired astronomers and topics including the formation and evolution of the Solar System's terrestrial planets.  We will test our curricula during this coming school year, as we did in  2007, at the Washington State  School for the Blind,  with the  expectation  of deeply  strengthening the  students' understanding of the  evolution of the Sun beyond what is available in their textbooks.  Ultimately, this curricula will be distributed and utilized throughout the United States as part of the on-going national and international efforts  to promote astronomy for those who are visually impaired.  We conclude with a description of our  role in building and testing additional educational tools.

Event related potentials (ERP) are electrophysiological responses of the brain measured during an electroencephalogram (EEG). The Mismatch Negativity (MMN) is an ERP component that occurs as a result of the brain detecting a deviant sound among a sequence of standards. It is represented by a negative peak in the fronto-central region of the scalp with latency 100-250 ms after onset of the abnormal stimulus. Previous studies have shown that the MMN is reduced in children with autism spectrum disorders (ASD) relative to typically developing children. It has been suggested that this indicates atypical automatic auditory processing in ASD. Other research has found abnormal MMN activity in schizophrenia patients as well. These studies have found an association between MMN activity and test measures of social function in individuals with schizophrenia. It has been theorized that impairment in auditory detection present in schizophrenia (as evidenced by a reduced MMN) may have downstream effects on certain facets of social cognition. No known work has yet been done to assess the same association in ASD. This study investigated the relationship of the MMN with social skills in individuals with ASD. In this study, EEG was recorded from children and adolescents with and without autism while they listened to auditory stimuli consisting of a standard sound ("ba") and deviant sounds ("da," "bi") to elicit an MMN. Parents reported on children’s social adaptive behavior in the Vineland assessment. The aims of this study are to (1) replicate previous findings that individuals with ASD have a reduced MMN relative to typically developing individuals, and (2) explore the relationship between the MMN and social behavior in children with ASD and typical development, as measured in the Vineland. A strong association may shed light on the sensory involvement in typical social functioning.

Autism is a developmental disability characterized by social deficits, communication deficits, and repetitive behaviors. Previous research has shown that having an older sibling with autism is a significant risk marker for a younger infant sibling developing ASD. The Early Connections study investigated the developmental trajectory of infants, looking for early markers that may predict whether or not ASD will be developed later on in toddlerhood. The two subject groups were identified as follows: high-risk (infants with an older sibling with ASD) and low-risk (infants that do not have any family history with ASD). Both groups were tracked longitudinally from 6 to 24 months at 6-month intervals. The Communication and Symbolic Behavior Scales Developmental Profile (CSBS DP), an assessment tool for early communication in infants and toddlers, was administered to both groups at 12 and 18 months. Each infant was videotaped during the CSBS DP administration and those videos were coded offline by trained undergraduate coders. Coding is still in progress. Using the CSBS DP, previous studies have shown that delayed word, sound, and language development are consistent markers for ASD. Therefore, we expect infants from the high-risk group to have lower CSBS DP scores in word and sound acquisition domains when compared to the low risk-group. A better understanding of early deficits in the core elements of language development will provide researchers with clearer insight on early identifiable signs of ASD. Targeted intervention in language acquisition may help children at high risk for ASD overcome potential communication deficits earlier on in development, thereby improving future prognosis.

Autism is a disorder characterized by deficits in social and communication skills and repetitive behaviors. Fifty-two percent of the children with autism are treated with medication for some of the common co-morbid behaviors – e.g., anxiety, aggression, and hyperactivity. However, only 49-69% of these children respond positively to the medication, and about 18-26% of these children experience side effects such as insomnia, sedation, and increased appetite. An extensive series of trial-and-error might be needed for a patient, which could be time-consuming and stressful for both the patient and parents. A reliable method is needed to predict the effectiveness of the pharmacological treatment. This study used electroencephalography (EEG) to detect early changes in the brain that we cannot yet observe in behavior. Children who are diagnosed with autism and starting a medication (e.g. stimulant, antidepressant, or atypical antipsychotics) participated in this study. EEG was recorded while the subjects participated in a social processing task, a resting task, and the Go-NoGo inhibition task. The participant’s caregiver completed three questionnaires: Child and Adolescent Symptom Inventory, Aberrant Behavior Checklist, and Social Communication Questionnaire. This project analyzed the subject’s change in EEG and behavioral data over three different time points (T1= before, T2= one week after, T3= one month after the start of medication). Multiple aspects of each individual’s EEG signal were examined by comparing the difference from T1-T2 and T1-T3 against the null hypotheses of no change (or comparing change to 0). The goal of this project is to search changes in the EEG signal that is related to positive (or negative) behavioral changes in this population. This study will provide an important first step for understanding changes in the brain in response to medications, which may provide useful information to professionals during the process of choosing the most effective medication for children with autism.

Triadic eye gaze, a form of coordinated attention, is defined as an infants’ eye gaze shifts between another person, and an outside object or person. The current study examined whether 9-month-olds’ triadic eye gaze influences language learning; we specifically asked whether infants who engage in more episodes of triadic eye gaze show increased phoneme learning in a foreign language. The current project was conducted as part of a larger research endeavor, the Interactive Exposure study, which examined infant language learning in the context of peer social interactions. In the Interactive Exposure study, infants were exposed to a foreign language, Mandarin Chinese, through individual and peer language exposure sessions. In 12 sessions over four weeks the infants watched video clips of Mandarin Chinese. Infants activated the 20-second video clips by touching the screen. Infants in individual exposure sessions were in the room with only the touchscreen and their caregiver whereas peer exposure sessions consisted of two infants and two caregivers. Following exposure, infants’ discrimination of the Mandarin Chinese phonemes was tested via Conditioned Head Turn procedure and an ERP task. Fifteen 9-month-old participants from the peer language exposure sessions were selected for the current analysis of triadic eye gaze patterns. Using ELAN coding software, infants’ eye gaze was coded for looks to their own caregiver, other caregiver, other infant, and screen. Next, episodes of triadic eye gaze were identified for eye gaze patterns that consisted of looks between the other infant, caregiver, other caregiver and screen (e,g,, other infant – TV – other infant). Although coding and analysis are currently underway, we predict that infants who engage in more episodes of triadic eye gaze will show increased phoneme learning. If our prediction is accurate, this finding will indicate that language learning requires complex social interactions, such as triadic patterns of attention.  

Individuals with autism spectrum disorder (ASD) demonstrate impairment in communicating with others and responding to social cues appropriately. These impairments may extend to family members. The Broader Autism Phenotype (BAP) refers to relatives of individuals with ASD who exhibit impairments similar to those with ASD. BAP suggests that some traits of ASD may be inherited separately and exist in individuals without ASD. Social language impairment is consistently observed in individuals with ASD. Twins are useful in studying the genetic components of a disorder, because they share 50% (dizygotic) or 100% (monozygotic) of their genes. This study examined the presence of BAP traits in disconcordant twin pairs (where only one twin has an ASD diagnosis) compared to twin pairs with typical development. twins aged 7 to 30 years completed a 15-20 minute conversation with an experimenter, which was later coded for pragmatic (social) language abilities using the Pragmatic Language Scale (PRS). In the PRS, coders blind to diagnosis, rated individuals on skills such as eye contact, intonation, facial expression and reciprocity of conversation. First, analyses compared pragmatic language in three groups: (1) the twin with ASD, (2) the unaffected twin of the child with ASD, and (3) an age and gender matched typical twin with no family history of ASD. We expected that pragmatic language was most impaired in the ASD group compared to the typical group, with the unaffected twin showing intermediacy performance, suggesting that pragmatics are part of the broader phenotype. Next, we compared the relationship of symptom severity in the twin with ASD and the level of pragmatic language in their unaffected sibling. This study will provide insight as to whether pragmatic language skills are a part of the broader autism phenotype and the degree to which they are related to familial autism symptoms.

The purpose of this paper is to investigate transnational influence in the poetry of Sarah Piatt, a recently recovered nineteenth century American poet. Piatt’s verse, considered by some to be the best poetry of her time second only to the work of Emily Dickinson, is remarkable for its quantity and breadth, but more importantly, for its subversive use of genteel style. Though her poems are generally divided into four overlapping categories, the two thematic classes of her poetry that will be explored in the most detail here are her Civil War poems and her “Irish poems,” which were inspired by an eleven year experience living in Ireland. These poems are examined through close reading and transnational analysis, as a conceptual link exists between Piatt’s perspective of the South during the American Civil War and her depiction of social injustice in her poems about Ireland and the Irish peasantry. These different contexts illustrate how Piatt brings her experience of civil strife and injustice in the United States to Ireland with her, influencing her understanding of political events in Ireland and her sympathies toward the destitute Irish people. As these conceptual ligaments are rarely one-sided, this paper seeks to illuminate the multi-directional nature of the transnational influence that impacts the way that Sarah Piatt’s poetry negotiates understanding at both local and global levels. By examining the complex dynamics of Piatt’s poetry, we can aid not only in the recovery of a deserving poet’s verse, but also clarify our understanding of nineteenth century women’s poetry as a rich body of work which merits greater consideration.

With the rise of atmospheric carbon dioxide, understanding the various facets of the carbon cycle is critical. In temperate coastal systems, the phytoplankton group of diatoms play a key role in the carbon cycle by sequestering carbon from the atmosphere into deep ocean sediments. Many scientists turn to laboratory culturing experiments to make predictions about the response of phytoplankton to changes in climate. But do these laboratory studies serve as realistic proxies for environmental responses? This study will compare growth rates of phytoplankton communities from Barkley Sound, British Columbia using field and laboratory experiments. Field experiments will comprise an in situ community growth rate measured using diffusion chambers in addition to on-ship incubations measuring the community growth rate in response to added nutrients. Field samples will be used to isolate the three dominant diatom species into a mixed-species culture for laboratory experiments. An analogous culture using laboratory isolates of the same species will be created, and the two cultures will be kept in a semi-continuous batch culture experiment tracking the growth rates in response to added nutrients. Comparisons of the growth rates in situ, shipboard, and in the laboratory will indicate how growth rates differ between natural phytoplankton assemblages and laboratory settings. Growth rates will be calculated using changes in chlorophyll a levels, a proxy for cell densities. If growth rates are much higher in the laboratory cultures than in the wild cultures, the implication is that there are limitations to growth in the natural environment that should be factored in when correlating laboratory experiments to the responses of natural phytoplankton assemblages. However, if there is no significant difference in growth rates between the experiments, then the laboratory conditions can provide similar conditions as in the field and laboratory culture experiments and can be easily used to predict environmental responses.

My research details how the austerity measures enacted at the federal, state and county levels have impacted women's reproductive healthcare in Washington State since 2008. This project examines how public-private partnerships have emerged in response to widening disparities and cutbacks in women's reproductive healthcare access and provisioning. Through a case study of an NGO dedicated to enhancing women's access to reproductive health care, I demonstrate that new models of public health provisioning are emerging to fill the void left by the neoliberal rollback of state sponsored public health programs. In order to examine the ways in which austerity measures have impacted women's access to reproductive healthcare services in Washington State, I engaged in archival analysis of State budget documents detailing cutbacks/shifts in public health funding for the past five years. Additionally, I interviewed employees of the Washington Department of Health (DOH) and King County Public Health (KCPH) about the impact of funding decreases on their service provision programs. After establishing this broad landscape of state disinvestment, I moved into an examination of my case study organization and the ways in which shifts in funding structures for public health have facilitated the creation of new models of health governance.

Extrasolar planets are being discovered at an incredible rate today. We have yet to discover another planet that can support life as we know it, but that will very likely change soon. Currently, most exoplanets are discovered indirectly by the influence they have on their host stars. Therefore, we only know the temperature and size of an exoplanet as well as we know the temperature and size of the star it orbits. For low-mass stars in the spectral range between K5 and M2, models do not provide the desired accuracy for these parameters. I improve this accuracy for a sample of planet candidates discovered by the Kepler Space Telescope by using a technique that assigns the parameters of nearby and well studied "stellar twins" to the planet hosting stars. I find these stellar twins by comparing the spectra of planet hosting stars to the spectra of similar nearby stars. By assigning the parameters of the nearby stellar twins to the planet hosting stars, I reduce the uncertainties in size and temperature for the planet hosting stars. This will also reduce the uncertainties in the size and temperature of the exoplanets, and thus allow for a better determination of their habitability.

MicroRNAs are a class of post-transcriptional regulators that silence messenger RNAs. MicroRNAs are interesting molecules to study because they are stable at room temperature and are long lived unlike messenger RNA. These characteristics make them useful molecular biomarkers to monitor disease and exposure status. For example, urine microRNAs have been used clinically as potential diagnostic markers of bladder cancer. However, their utility in non-clinical settings has yet to be elucidated. The goal of this study is to compare total RNA isolated from fresh and archived urine field samples to investigate their quality and quantity over time. RNA will be isolated from both whole urine and urine sediments and will be analyzed using multiple techniques. To date we have optimized the methodology required to isolate total RNA from the whole urine sample and the sediment. In a preliminary study, we isolated total RNA from samples under various conditions (fresh vs. field; whole urine vs. sediment) and compared them using the Nanodrop and Bioanalyzer. Our results demonstrate that RNA can be isolated from both fractions under both conditions. The molecular profiling of the RNA suggests that the urine samples contain only small RNAs because they lack ribosomal RNA peaks. Interestingly, the profiles look similar for all urine samples examined. In light of this, we performed an additional microarray experiment to characterize and identify the small RNAs present in the whole urine and sediment samples. These results are currently in progress. Using the information obtained from the preliminary microarray study, we will select the 3 most abundant microRNAs present in the urine for further analysis using RT PCR techniques to determine whether archival duration has an effect on their stability. The results of this experiment will provide valuable insight on the utility of archived field samples for the future development of urine biomarkers.

In most eukaryotic organisms, sexual reproduction is a critical component of the life cycle. Through meiosis, diploid cells containing two copies of each chromosome divide to produce genetically diverse haploid gametes (e.g. sperm) that contain one copy of each chromosome. This process is fundamental in sexual reproduction. Generally, meiosis results in a 50:50 transmission of heterozygous alleles into gametes. For example, human males make approximately 50% sperm with an X chromosome and 50% with a Y chromosome. Because only one copy of each chromosome can contribute to a given offspring, there is an evolutionary pressure on alleles to compete for preferential inclusion in gametes. Sometimes alleles can “cheat” to gain a greater than 50% transmission through meiosis. This is known as meiotic drive. Meiotic drive could have significant implications: altering fertility, speciation, and the evolution of chromosomes in eukaryotic organisms. For example, competition between alleles may be driving the rapid evolution of chromosome segregation factors acting during meiosis and mitosis, potentially driving chromosome segregation away from a theoretical ideal. Though meiotic drive has not been well understood due to limited model systems, we have developed a novel system utilizing genetically tractable fission yeast S. pombe and S. kambucha, to investigate meiotic conflicts between competing alleles. In S. pombe, heterozygous alleles are widely thought to segregate fairly in meiosis, suggesting that active meiotic drive loci are not present in this organism. We have found that silenced meiotic drivers can be de-repressed in aged germ cells, leading to greater than 90% transmission of certain alleles through meiosis. This provides experimental evidence in support of the evolution of cheating in meiotic processes that could ultimately result in decreased fertility amongst eukaryotic organisms, including humans. 

Lily blooming has recently been suggested to result from differential growth of the petals. The tissue expands along the edges, making them longer than the midrib. To accommodate for this excess length, the petal reverses its curvature, causing the bud to open. This is the growth driven mechanism for lily blooming. We inquired into the shape of the ripples resulting from edge growth and if we could observe direct evidence of the growth. We first investigated rippling, another consequence of edge growth. When the growth rate is high enough, lily petals ripple and their edges adopt their characteristic wavy shape. Using time-lapse imaging, we observed lily petals' edges rippling. We monitored the formation of several generations of ripples, with a fractal-like pattern of smaller waves superimposed onto larger ones. We also measured the temporal evolution of the ripples' wavelength, amplitude and arc length. We found that these quantities could be related using a geometric argument. Agreement between our prediction and observations is excellent. This indicates that in addition to biology, physics plays a significant role in determining the shape of lily petals. Second, we sought to quantify edge growth. We took quantitative measurements of the different growth rates, by tracking the positions of marks along the edge and along the midrib. We found that the growth rate is 35% larger along the edge than along the midrib, supporting the edge growth driven blooming model. We now want to measure the growth rates of different lily species, and investigate whether smaller growth rates can correlate to the absence of ripples. The purpose was to understand the 3D shape resulting from growth in a 2D sheet to supply knowledge leading to understanding plant development. It will also lead to applications in the packaging industry where flat shapes are made into 3D objects.

 Among individuals diagnosed with autism spectrum disorder (ASD), a delay or diminishment of the development of language and communication is found to be a core feature of the disorder. Children with ASD are also found to have more difficulty with verbal working memory tasks when compared to typically developing individuals, although findings have been mixed. In other clinical populations in which communication is impaired, one aspect of language that has been found to be related to verbal working memory is narrative ability, though this has not been thoroughly tested among children with ASD. Previous work has shown that verbal working memory relates to communication skills in children with ASD, albeit this study did not investigate narrative ability specifically. The current study had the goal of investigating the relation between verbal working memory and narrative ability in children with ASD. Data was collected from 21 participants. Participants were children from 6 to 11 years of age with autism spectrum disorder and average or above average IQ. Working memory was measured with the Children’s Memory Scale Numbers subtest, and narrative ability was coded from a speech sample obtained during the Autism Diagnostic Observation Schedule. The planned analysis was a partial correlation between verbal working memory and narrative ability controlling for IQ. Our prediction was that better verbal working memory would be a predictor for stronger narrative ability above and beyond IQ.

During the postembryonic transformation from larva to adult, zebrafish undergo a dramatic metamorphosis in pigment pattern. New pigment cells differentiate, interact, and migrate to form stripes of black cells (melanophores) and the interstripe regions of yellow cells (xanthophores); this pigment pattern characterizes adult zebrafish. My project investigates the roles of thyroid hormone (TH) in this dramatic transformation. We have produced a stable transgenic line expressing a transgene for nitroreductase exclusively in the thyroid gland. When I expose these transgenic fish to the drug metronidazole, toxic byproducts are produced in the thyroid gland, causing cell death and ablating the gland and preventing the fish from producing any TH. Using these thyroid ablated fish, I have characterized pigment cell differentiation and pattern formation in the absence of TH. I find that these thyroid ablated individuals do not develop xanthophores and show resulting disruptions in stripe boundary formation. Our lab has also found a zebrafish pigment mutant (opallus), which produces an excess of xanthophores. Mapping data from this mutant leads us to hypothesize that the phenotype is caused by a gain-of-function mutation in the receptor that stimulates TH production in the thyroid gland. I test the prediction that the excess xanthophore phenotype is caused by overproduction of TH by blocking TH synthesis using the drug methimazole, and show that these treatments rescue the opallus pigment phenotype, returning them to a wild-type pigment pattern. Moreover, I test the prediction that exposing wild-type zebrafish to exogenous TH produces an opallus-like pigment pattern. Thus, by quantifying the number of melanophores and xanthophores and their distribution across the flank in these hypothyroid and hyperthyroid backgrounds, I show that TH is both necessary and sufficient for xanthophore differentiation, and that both too much and too little thyroid hormone during the adult transformation grossly disrupts the formation of adult stripes.