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Hierarchically Porous M-N-C (M = Co and Fe) Single-Atom Electrocatalysts for Fuel Cells

Hierarchically Porous M-N-C (M = Co and Fe) Single-Atom Electrocatalysts for Fuel Cells

Primary author: Zhaoyuan Lyu
Faculty sponsor: Yuehe Lin

Primary college/unit: Voiland College of Engineering and Architecture
Campus: Pullman

Abstract:

The integration of hydrogen into power generation applications is critical for an environmentally friendly and sustainable energy pattern. Fuel cells are considered as one of the cleanest energy conversion technologies. The efficiency and cost of fuel cells, however, are still hurdled by the development of cost-effective catalysts that reduces oxygen at the cathode side. Currently, there is an intensive research effort for highly efficient electrocatalysts based on low-cost and earth-abundant elements. Improving non-precious metal catalysts require rational control over their size, shape, composition, and structure. In particular, single-atom catalysts (SACs) show great promise owing to their high catalytic activity, stability, selectivity, and 100?% atom utilization. Through innovative synthesis methods, we have developed a universal strategy to design and construct hierarchically porous SACs with highly active sites, MN2 (M = Fe or Co), which outperform the commercial precious-metal catalysts and show great potential for practical proton-exchange membrane fuel cells. Combining advanced characterization techniques and theoretical simulation, we further unravel the origin of the high catalytic activity of SACs at the atomic level. The findings shed light on the catalytic reaction mechanism of SACs and may help future development of low-cost and highly efficient fuel cell catalysts.

Breastfeeding patterns in four cultures: A cross cultural analysis

Breastfeeding patterns in four cultures: A cross cultural analysis

Primary author: Courtney Love
Co-authors: Katherine Flores, Beatrice Caffe, Avery Lane, Courtney Helfrecht, Courtney L. Meehan
Faculty sponsor: Courtney Meehan

Primary college/unit: Arts and Sciences
Campus: Pullman

Abstract:

Breastfeeding, widely acknowledged to have significant benefits to infant growth and development, maternal-infant bonding, and infant immunity, is also one of the most intensive and energetically expensive forms of maternal investment. Despite these noteworthy benefits, we lack foundational data regarding the underlying daily structure (e.g., frequency and number of bouts, temporal and developmental variation) of breastfeeding, particularly in cross-cultural perspective. Here we present data on breastfeeding structure in four cultures and test the broad hypothesis that maternal and infant life history characteristics and allomaternal investment are related to infant nursing patterns. Data were analyzed on 226 infants and children via naturalistic focal follow behavioral observations, which recorded infant behavior every 30 seconds across daylight hours, among hunter-gatherers and horticulturalists in the Central African Republic, agro-pastoralists in Ethiopia, and Washington/Idaho women living in a semi-rural community in the US. Our results support the hypotheses that several life history characteristics (e.g., infant age, sex, and allomaternal network size) are associated with nursing frequency. Understanding the daily structure of breastfeeding across subsistence patterns can help us understand cross-cultural variation, in addition to illustrating how life history traits influence maternal investment strategies on a critical investment pattern with clear fitness consequences.

Sales-Service Ambidexterity on Salesperson Performance: Do Role Characteristics Play a Role?

Sales-Service Ambidexterity on Salesperson Performance: Do Role Characteristics Play a Role?

Primary author: Muzi Liu
Co-author(s): Muzi Liu; Pavan Munaganti
Faculty sponsor: Dr. Babu John Mariadoss

Primary college/unit: Carson College of Business
Campus: Pullman

Abstract:

Firms are increasingly requiring their frontline employees to play an ambidextrous role, that is, engage in “both sales and service activities regardless of formal title or position” (Rapp et al. 2017, 59). While ambidexterity refers to the simultaneous pursuit of dual, and often conflicting strategic goals (Simsek 2009), service researchers have focused on service-sales ambidexterity by examining service personnel who perform sales activities (e.g., Gwinner et al. 2005; Jasmand, Blazevic, & de Ruyter 2012), and sales researchers have focused on sales-service ambidexterity by examining service performance within the salesforce (e.g., Ahearne, Jelinek, & Jones 2007). Recent research (e.g., Rapp et al. 2017) suggests that the capacity of employees to function ambidextrously depends on whether their dual sales and service roles are perceived as a stressor, and whether firms can create conditions facilitating role integration and reconciling competing individual-level role demands, leading to successful alignment between customer service and sales. Extant literature (e.g., Singh 1998; Johnson, Anderson, & Fornell 1995) suggests that the blurring of roles between sales and service personnel can have implications on employee role characteristics such as role conflict, role ambiguity and role overload, and ultimately affect performance. The purpose of this research is to examine the effect of ambidexterity on performance, through the mediating effect of salesperson role characteristics. In two studies, we find that sales-service ambidexterity leads to increased perceived role conflict, ambiguity, and overload amongst frontline employees, and ultimately in diminished frontline employee performance.

REMOTE: VOICES OF THE WILDERNESS

REMOTE: VOICES OF THE WILDERNESS

Primary author: DJ Lee

Primary college/unit: Arts and Sciences
Campus: Pullman

Abstract:

The Selway-Bitterroot Wilderness, one of the most remote landscapes in the U.S., stretches across Idaho and Montana in the Northern Rockies, where it borders the Frank Church River of No Return and the Gospel Hump Wildernesses to form the largest roadless wildland in the lower 48 states at over 5 million acres. I, my co-PI at the University of Idaho, WSU graduate students, and digital librarians, received the prestigious NEH Collaborative Research Grant for the Selway-Bitterroot Wilderness History Project in 2010. We collected 16 linear feet of photographs, maps, and documents and conducted 50 oral history interviews—the first ever digital and analog archive of a single Wilderness area. In 2014, our project was honored during the 50th anniversary of the Wilderness Act, solidifying its importance to Wilderness studies in the U.S. and worldwide. Since then, the value of Wilderness has increased globally as it becomes clear how vital large, roadless wildlands are for carbon sequestration, wild animal habitat, and biodiversity, not to mention spiritual renewal. Two creative products designed to reach larger audiences have grown from the project: 1) a podcast of curated stories from oral history interviewees with photo slideshows; 2) my creative nonfiction book, REMOTE: FINDING HOME IN THE BITTERROOTS from Oregon State University Press, forthcoming March 3, 2020. REMOTE was featured as one the most anticipated books by the Pacific Northwest Bookseller’s Association in October 2019. My Showcase Poster will focus on the creative products and processes of the Selway-Bitterroot Wilderness Project.

Acute Effects of High-Potency Cannabis on Everyday Life Cognition

Acute Effects of High-Potency Cannabis on Everyday Life Cognition

Primary author: Emily LaFrance
Faculty sponsor: Carrie Cuttler, PhD

Primary college/unit: Arts and Sciences
Campus: Pullman

Abstract:

Previous research indicates that tetrahydrocannabinol (THC), the primary constituent in cannabis, impairs memory and may affect risky decision-making. A small body of research further suggests that cannabidiol (CBD), which is also found in cannabis, may offset memory impairments. However, research demonstrating these effects has primarily utilized low THC ( 20% THC) cannabis and cannabis concentrates (> 60% THC) on cognition, and ii) to assess the role of CBD in the acute effects of cannabis on cognition. To achieve these aims, a between-subjects field experiment using Zoom videoconferencing software was employed. Participants in this study purchased a specific type of cannabis and then engaged in videoconferencing testing session from their home via Zoom. During this session, participants were observed while inhaling cannabis or remaining sober, and then completed tests of their memory (prospective, source, temporal order, and false memory) and decision making (risky choice framing, consistency in risk perception, resistance to sunk cost, and over/under confidence). Most of these tests measure aspects of cognition that have never been investigated under conditions of acute cannabis intoxication. Preliminary results indicate that cannabis intoxication impairs source memory and false memory but does not significantly impact decision making. CBD does not appear to offset these impairments. Results of this study have implications for cannabis users, and health practitioners working with cannabis-using populations.

Herbicide Detection with Nanoparticle-Amplified Immunoassays

Herbicide Detection with Nanoparticle-Amplified Immunoassays

Primary author: Eunice Kwon
Faculty sponsor: Bernard Van Wie

Primary college/unit: Voiland College of Engineering and Architecture
Campus: Pullman

Abstract:

New detection methods are being developed to monitor potentially harmful pesticides and herbicides, which are suspected of contributing to ailments ranging from diarrhea to death. In this study, we present the detection of the herbicide atrazine—approximately 65 million pounds of which are used in the United States per year—with two types of immunoassay while using a novel mesoporous palladium@platinum (Pd@Pt) core-shell nanoparticle (NP) detection label. Pd@Pt NPs have peroxidase-like catalytic activity, reducing hydrogen peroxide while oxidizing the substrate, resulting in higher pH- and thermo-stability than enzymes and greater catalytic activity than monometallic Pt black. We replaced the enzyme in the indirect ELISA method with Pd@Pt NPs, forming a nanoparticle-linked immunosorbent assay (NLISA) that eliminated a step in the detection process. We used this competitive NLISA on atrazine, yielding a limit of detection of 0.5 ppb (10% inhibition) with 0.1 – 500 ppb linear range, then on water samples spiked with atrazine at three concentrations, yielding 98 – 115 % recoveries. We then used LFIA with a Pd@Pt NP detection label on atrazine; in this case, test line intensity increased with decreasing atrazine concentration, because competitive immunoassays yield inverse results. Finally, we evaluated our methods by comparing our results with those obtained with the instrumental assay HPLC, which yielded an atrazine limit of detection of 10 ppb. We found that our novel Pd@Pt NP detection label has a higher sensitivity than HPLC and that NLISA saves time and reagents by eliminating the secondary antibody step.

Tropomyosin binding is essential for tropomodulin to regulate spine reorganization

Tropomyosin binding is essential for tropomodulin to regulate spine reorganization

Primary author: Balaganesh Kuruba
Faculty sponsor: Alla Kostyukova

Primary college/unit: Voiland College of Engineering and Architecture
Campus: Pullman

Abstract:

Formation of connections between neurons (synapses) is essential for proper brain function. Synapses are formed by axon terminals and dendrites (spines and shafts). Spine formation and reorganization depend on actin polymerization and depolymerization. Disruption in this process affects spine formation and thereby impairs many brain cognitive functions. Tropomodulin is a protein which controls polymerization of actin by binding to actin via tropomyosin, another actin binding protein. In our study, we showed that disruption of tropomyosin-binding ability of tropomodulin 2 resulted in changes in spine morphology, overall reduction of spine density and average spine length in primary hippocampal neurons. Tropomodulin interacts with two tropomyosin molecules during regulation of actin polymerization. No atomic structural information is available for the binding interface between tropomodulin and tropomyosin. Establishing the structure is critical to understand the actin dynamics regulation mechanism by tropomodulin. Using circular dichroism and nuclear magnetic resonance spectroscopic studies, we showed that tropomyosin peptide containing first 44 N-terminal residues is the optimal fragment to form respective stable complexes with the two tropomyosin-binding sites in tropomodulin.

Moving to Better Health Care? Evidence from the Impact of Medicaid Expansion on Homeless Individuals in the U.S.

Moving to Better Health Care? Evidence from the Impact of Medicaid Expansion on Homeless Individuals in the U.S.

Primary author: Ashutosh Kumar
Faculty sponsor: Ben Cowan

Primary college/unit: Agricultural, Human and Natural Resource Sciences
Campus: Pullman

Abstract:

Homeless individuals grapple with varied health problems but have limited access to health care. This study extends the literature on health care and homelessness and provides the first causal evidence of the impact of the Medicaid expansion on migration of homeless individuals from non-expansion to expansion states. The Medicaid expansion, adopted by 26 states and Washington DC and rejected by 24 states in January 2014, expanded coverage to previously uninsured homeless individuals. Besides health care, the expansion equipped homeless service providers with extra flexibility to tackle homelessness through several supportive services and housing-related activities, absent in non-expansion states. Using the state level data, released by the Department of Housing and Urban Development (HUD), on the homeless population from 2009-2018, estimates from a difference-in-differences model suggest migration of homeless individuals, where expansion states saw statistically significant 4.4 percent increase, while non-expansion states simultaneously experienced a 22.6 percent decline. Furthermore, utilizing the difference in coverage status of homeless individuals vis-a-vis homeless people in families (who had pre-expansion coverage), estimates from a triple difference (DDD) model also confirm a significant migration. Previous studies documenting the positive impact of Medicaid expansion on a number of outcomes – improved coverage and health care utilization, reduced financial hardships and medical bills sent to collection, and increased household savings – compliment the results of this study. This paper provides additional evidences that Medicaid expansion had no significant impact on the number of homeless veterans or on indicators like bankruptcy, unemployment rate and poverty rate.

The Use of Ecological Momentary Assessment Protocols in Neuropsychology: A Meta-Analysis

The Use of Ecological Momentary Assessment Protocols in Neuropsychology: A Meta-Analysis

Primary author: Olasunkanmi Kehinde
Co-author(s): Maureen Schmitter-Edgecombe
Faculty sponsor: Prof. Maureen Schmitter-Edgecombe

Primary college/unit: College of Education
Campus: Pullman

Abstract:

The aim of this meta-analysis is to examine the use of Ecological Momentary Assessment (EMA) protocols in different kinds of neuropsychological disorders to uncover the different factors that could moderate the effectiveness of EMA protocols in neuropsychology. Studies with the use of EMA to collect neuropsychological and psychological disorder data in the last 10 years were considered. A meta-analysis of 16 studies was performed to investigate the design characteristics of EMA protocols and possible factors that could moderate the effective use of EMA protocols in measuring any form of disorder in neuropsychology. Overall, the use of EMA protocols in measuring the neuropsychological and psychological disorder across studies were found to be effective (g =0.32). The distribution was heterogeneous Q (15) = 492.48, p < .05, I^2 = 96.95. A total of 97% of the variance that is due to true heterogeneity was between-studies variance while 3% of the variance was within-study variance based on sampling error. The studies with incentives, daily random prompts, duration of EMA, and the length of EMA might positively promote the quality of data collected from participants who are diagnosed with a neurological or psychological disorder. This meta-analysis has implications for the ways psychological disorders are measured momentarily.

Keywords: Protocol; Neuropsychology; Ecological Momentary Assessment

Pricing Strategies in the Presence of Interventions

Pricing Strategies in the Presence of Interventions

Primary author: Sadegh Kazemi
Faculty sponsor: Stergios B. Fotopoulos

Primary college/unit: Carson College of Business
Campus: Pullman

Abstract:

Motivated by real-life pricing practices, we consider a pricing problem under uncertain conditions where the customer’s willingness-to-pay (WtP) changes at an unknown point over the selling horizon. An important feature of our model is that the seller only observes the sales outcomes and has limited knowledge of the underlying WtP distribution before and after the intervention. Given the uncertainty associated with the seller’s estimate of the time of change, we obtain the probability distribution of the seller’s maximum likelihood estimate (MLE) of the intervention time. Furthermore, we characterize the seller’s expected revenue loss due to the under- or overestimation of the intervention time and propose an easily implementable procedure to approximate the seller’s revenue under-performance. Our study reveals two important findings. First, the seller tends to underestimate the intervention time in the face of negative events that lower the customer’s reservation price. Conversely, the seller is prone to overestimation when the intervention inflates the customer’s reservation price. Second, we show that the seller’s revenue under-performance is minimal both when the shift in WtP distribution parameter(s) is either very small or considerably large. While our analytical results significantly contribute to the revenue management literature on their own, we also provide an accurate numerical method to easily obtain and interpret the results in a meaningful way for managerial use.