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The genetic consequences of dam removal on the Elwha River for recolonizing Steelhead

The genetic consequences of dam removal on the Elwha River for recolonizing Steelhead

Primary Author: Alexandra Fraik

Faculty Sponsor: Joanna Kelley

 

Primary College/Unit: Arts and Sciences

Category: Physical and Social Sciences

Campus: Pullman

 

Abstract:

 

Dam construction and riverscape habitat fragmentation disrupt important life-histories and movement of aquatic species. Functionally, dams disrupt the movement of water, sediments, nutrients, and species between upstream and downstream. The Elwha and Glines Canyon dams in Washington state, constructed in the early 1900s, fragmented the Elwha River, restricting migratory species such as Oncorhynchus mykiss from ocean. Oncorhynchus mykiss exhibits multiple life-history phenotypes including a migratory form (anadromous Steelhead) and a freshwater non-migratory form (resident Rainbow Trout). The negative effects of dams on O. mykiss have been extensively documented (including population declines, loss of genetic diversity, extirpation), however few have studied their population genetics following dam removal. In 2012 and 2015, the Elwha River dams were removed and anadromous Steelhead recolonized formerly dammed regions. In this study, we characterized the genetic ancestry of recolonizing Steelhead into the previously dammed portions of the Elwha River watershed. Single nucleotide polymorphism genetic data were produced from 1,003 samples collected prior to, during and post dam removal from both life-history forms. Population structure analyses supported three genetic clusters primarily explained by dam location. Following dam removal genetic structure decreased. Using genetic stock identification, we determined recolonizing Steelhead were of mixed genetic ancestry with individuals derived from formerly dammed populations as well as below dam populations. Alleles putatively involved in the anadromous phenotype were detected in formerly dammed populations both prior to and post dam removal. These results have significant evolutionary implications for the conservation of migratory adaptive potential in O. mykiss populations facing changing riverscapes.

 

Development and Validation of Analytical Chart for 915 MHz Single-mode Microwave Assisted Thermal Processing Conditions

Development and Validation of Analytical Chart for 915 MHz Single-mode Microwave Assisted Thermal Processing Conditions

Primary Author: Yonas Gezahegn

Faculty Sponsor: JumingTang

 

Primary College/Unit: Agricultural, Human and Natural Resource Sciences

Category: Engineering and Environmental Science

Campus: Pullman

 

Abstract:

 

Microwave thermal processing has wide applications in the food industries such as drying, pasteurization and sterilization. In microwave heating understanding the relation between dielectric properties and processing conditions is key in accurately predicting the heating rate that ensures food safety. Hence, this research aims to develop an analytical chart that will relate the dielectric properties and processing conditions to accurately predicted the cold spot temperature in the center layer of food. By measuring some physical properties of food samples (mashed potato, rice and pea) and applying analytical equations the chart was developed using MATLAB2019a software. In predicting dielectric constant, the chart was accurate with 0 – 1.2%, 0.1 – 2.3% and 0 – 4.6% error, for the products respectively. The optimum salt content of 0.1%, 1% and 0.5% were discovered for higher heating rates, respectively. The best preheating temperatures were also determined, where higher salt content foods have a less preheating temperature for maximum heating rate. It was also possible to related dissipation power and heating rate to predict the cold spot temperature at a given microwave heating time. Using mashed potato sample 0% salt and 22 mm, 0.6% salt and 22 mm, 0.6% salt and 40 mm, 0.1% salt and 40 mm, 0% salt and 35 mm the temperature prediction error was only 0 – 2%,  0 – 3%, 0 – 6%, 0 – 9%, and 0 – 6%, respectively. In conclusion, the analytical chart accurately predicts dielectric properties and processing conditions that can save time and resources

Examining Preservice Mathematics Teacher Learning About Equity

Examining Preservice Mathematics Teacher Learning About Equity

Primary Author: Melissa Graham

Faculty Sponsor: Roth McDuffie

 

Primary College/Unit: College of Education

Category: Arts and Education Sciences

Campus: Pullman

 

Abstract:

 

Principal Topic:

Prior to student teaching and field experiences, many preservice teachers (PSTs) lack opportunities to experience the challenges they will face in their future classrooms (Putnam & Borko, 2000). Most PSTs are White and female, which may not be representative of many in the population they will go on to teach, and many do not leave their teacher education programs prepared to teach diverse populations (Aguirre et al., 2012). My theoretical framework for this study lies at the intersection of situated learning theory and sociocultural theory, and I view teaching and learning as cultural practices. I researched how situating PST learning in the act of teaching through lesson study influences that learning.

 

Method:

In this study, I examined PST learning related to equity while in an experimental, practice-based mathematics methods course. In this course, the instructor used specific research-based activities (Roth McDuffie et al., 2014; Murata, 2011) to support PSTs in developing teaching practices that support diverse learners. I used qualitative methods to study how PSTs conceptions of equity in teaching and learning changed throughout the course. Data sources included interviews, student assignments, PST lesson plans, field notes, and videos of the lessons taught by PSTs.

 

Results/Implications:

My findings suggest that PSTs conceptions of equity changed substantially, and that specific course activities contributed to this change. This study has implications for mathematics teacher educators, a trajectory for PST learning, and the design of teacher education programs.

 

“Enrichment” Curriculum Plan: Creative Thought in Education Policy

“Enrichment” Curriculum Plan: Creative Thought in Education Policy

Primary Author: Kiersten Guetlein

Faculty Sponsor: AG Rud

 

Primary College/Unit: College of Education

Category: Arts and Education Sciences

Campus: Pullman

 

Abstract:

 

Principle Topic:

This project is a cursory curriculum plan for a hypothetical “enrichment” class designated for students at the 6-12 grade levels. The purpose of this project is to think creatively about ways to address multiple education policy concerns through new curriculum development in a practical, applicable manner. Projects such as this are necessary to push scholarly work into policy reform by presenting practical methods that can produce long-term change and be adopted into the current school systems.

 

Method:

This project begins with a brief overview of current concerns in education policy. In order to address these concerns, a curriculum plan for an “enrichment” course is proposed. The course aims to address policy concerns in a manner that pushes boundaries while still operating within the current school structure. This is accomplished through a changing semester curriculum designed by local school officials according to the following five units: economy, environment, history in perspective, current events, and community.

 

Results/Implications:

This project addresses several concerns in education policy, including ability tracking, standardized testing, limited control in curriculum for local districts and teachers, and lack of diversity within curriculum. The required guidelines foster diversity in thought, critical thinking, and holistic education, helping to bridge gaps in the current curriculum. This project offers creative solutions to the field of education policy and has considerable potential; it not only addresses several concerns simultaneously but can also be implemented into existing schools’ structures.

 

Forest management and climate change effects on wildfire regimes of Cedar River Watershed

Forest management and climate change effects on wildfire regimes of Cedar River Watershed

Primary Author: Rebecca Gustine

Faculty Sponsor: Jennifer Adam

 

Primary College/Unit: Voiland College of Engineering and Architecture

Category: Engineering and Environmental Science

Campus: Pullman

 

Abstract:

 

Fire exclusion, fire suppression, and climate change have altered wildfire regimes in the Western Cascades during past decades. Fire season is becoming longer and burned area in the Western Cascades are projected to increase 200-400% above contemporary levels by the end of the century. Such fire-regime changes can have cascading consequences for human and natural systems, including degradation of downstream water quality. Understanding the potential consequences of an altered fire regime will be necessary for managing forested watersheds to protect highly valued resources, especially high-quality drinking water. In this study, we apply the ecohydrologic model RHESSys, coupled with the fire spread model WMFire, to investigate how climate change and forest management techniques, such as stand thinning, can affect wildfire regimes in the Cedar River Watershed in western Washington, which provides drinking water for 1.4 million people in greater Seattle area. We run multiple simulations considering different climate change and forest management scenarios to assess the vulnerability of wildfire activity in this watershed and the efficacy of management practices to reduce fire impacts. Results show that both forest management and climate change alter the fire regime in the Cedar River watershed with fire suppression increasing the mean fire size while climate change increased the frequency of fires. By using processes-based model with factor-controlled simulation experiments, we can better inform the water management authorities, such as Seattle Public Utilities, on how to best mitigate the risk of wildfire-induced harm to drinking water.

 

Technology-assisted vocabulary learning for EFL learners: A meta-analysis

Technology-assisted vocabulary learning for EFL learners: A meta-analysis

Primary Author: Tao Hao

Faculty Sponsor: Yuliya Ardasheva

 

Primary College/Unit: College of Education

Category: Arts and Education Sciences

Campus: Pullman

 

Abstract:

PRINCIPAL TOPIC

As an important constituting component of L2 acquisition, vocabulary learning has been significantly impacted by the emergence of new technologies. The current meta-analysis extended on previous work by synthesizing the EFL technology-assisted vocabulary learning research conducted between 2012 and 2018 to reconcile inconsistencies and to examine the effectiveness of more current technological tools on both vocabulary learning and retention.

 

METHOD

Two primary research questions guided this meta-analysis: 1) What are the effects of technologies on vocabulary learning in comparison with traditional pedagogies? 2) What are the moderator variables that have significant influences on the technology-assisted L2 vocabulary learning? A thorough and systematic literature search was conducted and a total of 33 research reports yielding 45 studies met the inclusion criterion. Studies were coded by two independent raters using a pre-established coding protocol for quality review.

 

RESULTS/IMPLICATIONS

The overall effect of technology-assisted L2 vocabulary learning was large (d = 0.845), suggesting that technology-assisted L2 vocabulary learning was more beneficial than non-technology-assisted instruction. Importantly, within-study comparison results indicated that technology could enhance learners’ long-term vocabulary retention.  Moderator analysis results also highlighted several variables—namely, device type, game condition, setting, test format, and reported reliability—affecting the effectiveness of vocabulary learning. These variables should be considered when planning instruction in technology-assisted L2 vocabulary learning. Specifically, advantages were found for mobile devices and on-the-move learning, suggesting that L2 vocabulary learning may be most efficient when students use mobile phones and are not restricted by classroom settings

Comparing Mother and Child Functioning among Preschoolers Attending Head Start and Private Preschools: The Importance of Father Involvement

Comparing Mother and Child Functioning among Preschoolers Attending Head Start and Private Preschools: The Importance of Father Involvement

Primary Author: Robyn Herbert

Faculty Sponsor: Tammy Barry

 

Primary College/Unit: Arts and Sciences

Category: Physical and Social Sciences

Campus: Pullman

 

Abstract:

 

Principal Topic

Fathers are more involved with their children compared to previous generations, making habits as parents important to family involvement research (e.g., Opondo et al., 2016). Research has demonstrated that increased levels of father involvement have been related to beneficial outcomes for children including academic achievement (e.g., Jeynes, 2015). Father involvement may be particularly important for families with a socioeconomic disadvantage (Atzaba-Poria et al., 2004). The current study examined mother and family variables as they relate to child behaviors, whether these variables differ due to Head Start status or family structure, and how these variables relate to spousal stress in two caregiver homes.

 

Method

Participants included 130 children and their mothers. Participants were recruited from Head Start centers and private preschools. Mothers completed the study questionnaires; children were tested at Head Start or their preschool.

 

Results/Implications

Results indicated children with a father in the home had higher cognitive functioning and their mothers used fewer negative parenting practices. Results also indicated that children who attend Head Start were more likely to have an absent father; however, if a father was present, mothers of children in Head Start experienced significantly lower levels of spouse/partner stress. The current study adds to previous research demonstrating that increased father involvement can benefit children and mothers. These results highlight points of intervention for children in Head Start, who may otherwise experience health and academic inequity. Results may inform family-based interventions in which mothers’ mental health is targeted in an effort to reduce negative parenting practices.

 

Comparison of Microwave-Assisted Thermal Pasteurization and High Pressure Processing as Pasteurization Methods for Green Beans

Comparison of Microwave-Assisted Thermal Pasteurization and High Pressure Processing as Pasteurization Methods for Green Beans

Primary Author: SUMEYYE INANOGLU

Faculty Sponsor: JumingTang

 

Primary College/Unit: Agricultural, Human and Natural Resource Sciences

Category: Agricultural and Natural Resource Sciences

Campus: Pullman

 

Abstract:

 

There has been an increasing consumer desire for high quality minimally processed food. The food industry is seeking new processing technologies to meet such consumer desire by producing ready-to-eat meals (RTE) with adequate shelf-life. Novel methods such as high pressure processing (HPP) and microwave-assisted pasteurization system (MAPS) can be the good candidates for food industry. The aim is to provide scientific support to food industry about both pasteurization methods.

Based on literature review, the mild pasteurization conditions were selected as 70°C-2 min for MAPS and 600 MPa-10 min at 25°C for HHP, respectively.  For the severe pasteurization, 90°C-10 min was selected for MAPS and 600 MPa-20 min at initial temperature of 45°C were selected for HPP. The quality attributes such as color, chlorophyll content, texture, and pH of green beans were determined at 2°C over 36 days and 10°C over 20 days and at 2°C over 14 weeks and 7°C over 7 weeks for mild and severe pasteurization, respectively.

Similar color change after both pasteurization methods shows that the processing temperature of MAPS did not negatively affect the color of green beans. Severe pasteurization conditions of MAPS and HPP resulted in more loss in green color. The severe MAPS conditions resulted in less retention of firmness in comparison with the severe HPP pasteurization. This can be attributed to the higher processing temperature (90°C), which results in β-eliminative depolymerization of pectin (softening). Microbial growth, mainly acid-producing microorganisms, might be attributed to the decrease in pH and undesirable appearance and smell.

 

Coordinated Voltage Control for Conservation Voltage Reduction in Power Distribution Systems

Coordinated Voltage Control for Conservation Voltage Reduction in Power Distribution Systems

Primary Author: Rahul Jha

Faculty Sponsor: Anamika Dubey

 

Primary College/Unit: Voiland College of Engineering and Architecture

Category: Engineering and Environmental Science

Campus: Pullman

 

Abstract:

 

Principle Topic

An efficient operation of the distribution grid can be achieved using network-level optimization modeled as a distribution optimal power flow (D-OPF) problem. However, the variable power generation profiles of distributed energy resources (DERs) may render the optimal control decisions that are obtained in advance using D-OPF methods to sub-optimal.

 

Method

For conservation voltage reduction (CVR), a coordinated centralized and local control approach is developed that simultaneously achieves the network-level objective, while mitigating the impacts of DERs variability on optimal control set-points. The centralized controller solves a D-OPF problem for substation power reduction using a bi-level approach to control the system’s legacy voltage control devices (voltage regulator and capacitor banks) and smart inverters. A penalty successive linear programming (PSLP) approach is used to obtain a computationally tractable D-OPF model. Next, an adaptive volt-var droop control for the local control of smart inverters is proposed to minimize the voltage deviations (due to DERs variability) with respect to the centralized control set-points.

 

Results/Implications

The proposed coordinated control approach is validated using the modified IEEE 123-node test system which has four voltage regulators, four capacitor banks and twenty-six DERs.  The results show that the proposed control simultaneously reduces the power consumption from the substation to achieve CVR objective and voltage violations due to DERs variability.

 

Stigma As a Moderator for the Relation between Race and Autism Spectrum Disorder Diagnoses

Stigma As a Moderator for the Relation between Race and Autism Spectrum Disorder Diagnoses

Primary Author: Shelby Johnson

Faculty Sponsor: Tammy Barry

 

Primary College/Unit: Arts and Sciences

Category: Physical and Social Sciences

Campus: Pullman

 

Abstract:

 

Principal topic: Past research has indicated that minority racial and ethnic groups in the United States face more barriers to accurate and timely autism spectrum disorder (ASD) diagnoses than their white counterparts. This project is designed to determine if stigma moderates the relation between race and the time lapse between symptom onset and ASD diagnosis.

 

Method: Data were collected from 152 parents of children with an ASD diagnosis. Parents reported at what age their child began showing signs of ASD, what age the child was officially diagnosed with ASD, and child’s race; they also completed a stigma scale measuring affective, behavioral, and cognitive stigma.

 

Results/implications: A t-test indicated that the time lapse between symptom onset and diagnosis did not significantly differ between white and non-white participants. Furthermore, the time lapse between symptom onset and diagnosis did not significantly relate to stigma. However, a regression analysis indicated that stigma moderated the relation between race and the time lapse in diagnosis when comparing white participants (n = 123, M = 21.63, SD = 17.36) to non-white participants (n = 29, M = 17.66, SD = 18.86) p = .02. These data suggest race and stigma play a significant role in how long it takes a child to receive an ASD diagnosis. Although neither race nor stigma individually related to the time lapse between onset and diagnosis, their interaction was significant. Parents of minority children who reported experiencing higher levels of stigma also reported the shortest time lapse between symptom onset and diagnosis.