Digital Commons Network^™

Flight System Development For A Bio-Inspired Rotating Empennage Experimental Unmanned Aerial Vehicle, Ashton Gilbert

All Graduate Theses and Dissertations, Fall 2023 to Present

Unmanned aerial systems, commonly known as drones, are increasingly used for research, environmental monitoring, and testing new aircraft concepts. Many commercially available drone flight controllers work well for standard aircraft designs, but they can be difficult to adapt for experimental vehicles that use unconventional control methods or require detailed monitoring during testing. This creates challenges for researchers who need flexible and reliable tools to safely evaluate new flight technologies. This work presents the development of a custom drone flight control system designed specifically for experimental research. The system integrates custom electronics and software that allow researchers to easily modify control …

Training General Educators To Collect Antecedent-Behavior-Consequence Data Using Behavioral Skills Training, Mckenna Larsen

All Graduate Theses and Dissertations, Fall 2023 to Present

Many schools use a three-tiered system to meet the needs of individual students. General education teachers are often not given the training to provide the supports they are expected to provide. Evidence shows that when interventions meet the need the student is trying to communicate, these interventions are more effective. This research looked at the effects of training that involved modeling, practice, and feedback, also known as Behavior Skills Training (BST), on general education teachers’ ability to collect data on students’ behavior. It also looked at how teaching educators to collect data influenced their belief in their ability to handle …

From Solitons To Chaos: Nonlinear Dynamics Of The Time-Fractional Modified Regularized Long-Wave Equation, Samsun Nahar Ananna, Chunhui Lu, Abdulla Al Mamun, Md Al Amin Meia, Nur Hasan Mahmud Shahen

School of Mathematical & Statistical Sciences Faculty Publications

This study investigates the nonlinear wave structures and complex dynamical behavior of the time-fractional modified regularized long-wave (mRLW) equation through an integrated analytical, numerical, and dynamical framework, with particular emphasis on connecting localized wave formation with perturbation-induced nonlinear dynamics. Within the adopted fractional framework, a Hirota-type bilinear approach is employed to construct one-wave, two-wave, three-wave, lump, one-lump–one-soliton, and one-lump–one-stripe structures, whose numerical consistency is subsequently examined using the Modified Variational Iteration (MVI) method through graphical comparisons and L 2 and L ∞ error norms. The periodically perturbed mRLW system is further investigated using phase portraits, Lyapunov exponents, bifurcation diagrams, Poincaré …

Just Energy Transition To A Low-Carbon Economy In The Arctic: The Case Of Alaska, Jus Tavcar

Arctic and Northern Studies

Increasingly, government jurisdictions are finding ways to reduce carbon use within their boundaries, but different locations use varied tactics to create low-carbon economies. Furthermore, not all cities, states, or nations focus on the issue of inequity and the need for justice in the transition, so that the transition costs are not far higher for already marginalized groups. Using Alaska, an Arctic petrostate, as a case study, my research question is: What form of a just energy transition best fits the needs of Alaska’s communities struggling with the impacts of climate change? To answer this question, my research is grounded in …

Exploring Competitive Dynamics Between Pseudomonas Baetica And Salmonella In A Polymicrobial System, Braxton E.M. Stout

Electronic Theses and Dissertations

The global rise in antimicrobial resistance has catalyzed a greater focus on polymicrobial research aimed at characterizing microbial interactions and uncovering new therapeutic strategies. Though it has long been of interest, environmental soil-derived bacteria remain largely under-represented in research and thus uncharacterized in this field. This project aimed to identify soil microbes that display inhibitory mechanisms to potential nosocomial pathogens. Soil sample S1S3-2 displayed inhibitory phenotypes toward numerous bacteria and was identified as Pseudomonas baetica. In both planktonic and biofilm growth, P. baetica was able to inhibit Salmonella arizonae through a contact-dependent and temperature-dependent manner. Screening of a transposon insertion …

Microbial Treatment Of Refinery Wastewater Enables Fluted Pumpkin Growth And Food Safety, Eziafakaego M. Ibo, Odera R. Umeh, Oju R. Ibor, Chukwunonso P. Okoli, Azubuike V. Chukwuka, Emmanuel D. Omogbemi, Michael U. Orji, Aina O. Adeogun

Montclair State University Scholarship & Creative Works

Global water scarcity necessitates the reuse of agricultural wastewater, but safety concerns persist about contaminant transfer to plants. This study examined how treated and untreated petroleum refinery wastewater affected the growth and development of fluted pumpkins over a six-week cultivation period. The novelty lies in our comprehensive assessment of both growth performance and contaminant bioaccumulation in fluted pumpkins. The experimental design planted fluted pumpkin seeds in soils irrigated with 100% treated wastewater, untreated wastewater, or tap water (control). Weekly growth indicators (leaf count and height) and post-harvest parameters (root length, chlorophyll concentration, fresh and dry weight) were measured, and heavy …

Machine Learning-Based Regression For Magnetic Field Prediction From Odmr Spectral Data, Jesse B. Hernandez

Electronic Theses, Projects, and Dissertations

Optically Detected Magnetic Resonance (ODMR) using nitrogen-vacancy (NV) centers in diamond enables sensitive, room-temperature magnetic field sensing, but real ODMR spectra are often noisy and difficult to analyze with traditional peak-fitting methods. This thesis investigates whether machine learning can reliably predict magnetic field strength directly from ODMR spectra, and compares four model families under a single regression task: a random forest, an artificial neural network (ANN), a one-dimensional convolutional neural network (1D-CNN), and a Transformer.

Training data were generated from an NV-ensemble simulation calibrated to real measurements provided by the Ulsan National Institute of Science and Technology (UNIST), spanning 0 …

Serotonin 1b/1a Receptor Modulation On Probabilistic Reversal Learning In The Btbr Mouse Model Of Autism Spectrum Disorder, Magdalena R. Gonzales

Electronic Theses, Projects, and Dissertations

Autism spectrum disorder (ASD) is known for developmental disability that typically emerges around infancy and early childhood due to a possible combination of genetics, environment or a combination of both. A diagnosis of ASD is determined by behavioral measures due to the lack of reliable biomarkers. Such symptoms include social impairment, and restricted and repetitive behaviors. Restricted and repetitive behaviors often present as rigid behavior or behavioral inflexibility. Behavioral flexibility is often described as the ability to adapt to changing environments. Previous research has shown that serotonin (5-HT) 1B and 1A receptor upregulation may attenuate restricted, repetitive behaviors found in …

Long-Term Analysis Of Pm2.5 Elemental Composition And Source Contributions In Coastal Urban Environments Of Corpus Christi And Houston In Texas, Sai Deepak Pinakana, Jeremy A. Sarnat, Amit U. Raysoni

School of Earth, Environmental, & Marine Sciences Faculty Publications

Long-term assessments of fine particulate matter play a key role in identifying persistent and emerging emission contributors. Coastal urban areas are highly susceptible to transboundary dust and wildfire events in addition to local pollution sources. Multi-decadal assessments in these regions using chemical speciation data could offer insights into major pollutant sources and their trends. This study utilizes nearly two decades of PM2.5 elemental composition data at two major coastal cities in Texas: Houston and Corpus Christi. Fourteen trace elements were analyzed to characterize the seasonal variability and long-term source evolution using a combination of Spearman’s correlation analysis, principal component analysis, …

Impact Of School Nurse Education On Factors Influencing Hpv Vaccine Communication With Parents, Jihye Choi, Efrat K Gabay, Jeanette Deason, Elizabeth Baumler, Diane Santa Maria, Daisy Mullassery, Lara S Savas, Erika Thompson, Sanghamitra M Misra, Paula M Cuccaro

Faculty, Staff and Student Publications

Human papillomavirus (HPV) can cause six cancer types but can be prevented with timely vaccination in early adolescence. However, despite the wide availability of the HPV vaccine, uptake remains suboptimal among US adolescents. School nurses are invaluable resources to students and their families regarding adolescent immunization needs. As part of the All for Them vaccination program, we assessed the impact of the continued nurse education (CNE) intervention on school nurses’ HPV vaccine communication with parents. Seventy-two school nurses and nurse administrators in Texas participated in the study. Using a single-arm study design, we measured participants’ potential barriers to and self-efficacy …

Ring Ring Goes The Telephone, Answer That Email: The Immediacy Of Information Communication Technologies And Their Effects On Employee Well-Being, Concepcion Rodriguez

Electronic Theses, Projects, and Dissertations

Rapid technological advances have resulted in information communication technologies (ICTs) with revolutionary capabilities, allowing employees easy access to the workplace without the impediments of time or space. Initial inception of ICTs in the workplace were expected to increase autonomy (Heller, 1989), but the ability to be reachable at any time proved disadvantageous to employee well-being by creating a culture in which immediate responses were expected and precipitating the psychological phenomenon of workplace telepressure, an overwhelming preoccupation and urge experienced by workers to respond to work-related messages (Barber & Santuzzi, 2015; Mazmanian et al., 2013). The current study centered on exploring …

Integrating Student-Mined Data In Youth Computer Science Learning: An Investigation Of Learning Outcomes And Educational Strategies, Alex Acquah

Open Access Theses & Dissertations

As data increasingly shapes participation in society, there is growing emphasis on preparing youth to engage with data through computer science education. Existing K-12 computing and data science curricula have expanded opportunities for learners to analyze and interpret data; however, many learning experiences continue to rely on datasets and inquiry structures designed by others, limiting authentic engagement, personal relevance, and learner agency. This dissertation investigates the integration of student-mined data in youth computer science learning and examines its influence on computational thinking, epistemic agency, and learning experiences among high school students. Using a qualitative approach, data collected from youths of …

Enhancing Teachers’ Intercultural Literacy: Examining The Impact Of A Fulbright-Hays Group Projects Abroad Program To Indonesia, Paul R. Wallace

Journal of Global Education and Research

The Fulbright-Hays Group Projects Abroad (GPA) Program offers institutional grants to support overseas experiences and curriculum development for educators. The study reported here focused on changes in the intercultural literacy of participants involved in a 4-week Fulbright-Hays GPA Program to Indonesia. Participants in this study included K-12 teachers from public schools and teacher education majors. Before and after traveling to Indonesia, eight participants completed a self-assessment of intercultural literacy, which measured competencies, understandings, attitudes, language proficiencies, participation, and identities deemed necessary for successful living and working in a cross-cultural environment. This article presents the results of the assessment survey, along …

Changing Expectations In Higher Education Post-Pandemic, Gregory R. Mackinnon, Tyler Maclean, Mohamad El Maouch, William Yuan, Zhao Kaibin, Bi Dandan, Marwa Saab

Journal of Global Education and Research

A sample of higher education students in Canada and China was surveyed and interviewed to ascertain any changes in their educational expectations given their experiences with emergency remote teaching during the pandemic. In addition, the instructors of these students were interviewed to corroborate student feedback. The research suggested that students in Canada and China expressed expectations of increased flexibility and improved pedagogy. Whereas Canadian students were overtly demanding of the instructor and the educational system, Chinese students were comparatively subtle in their expectation that the post-pandemic level of support be maintained. The primary concern of the Chinese cohort was a …

Advancing Blended Education: Caribbean Lecturers’ Reflective Narratives Of Caution, Creativity, And Change, Mia A. Jules, Donna-Maria B. Maynard, Grace A. Fayombo, Jason E. Marshall, Tanya Newton, Kamilah Hutson, Amanda Kellman, Cherise Bynoe, Mikaila Collymore, Jo-Ann Prosper-Chase, Laura Lee Foster, Adicia Clarke

Journal of Global Education and Research

Blended teaching requires lecturers to constantly self-reflect on their pedagogical practice to enhance student learning. However, there is yet to be a significant corpus of literature that highlights the cognitive resources that lecturers in higher education should possess to effectively use blended learning strategies. It is important to understand the intellectual resources required for blended pedagogy so that such capabilities can be fostered during faculty-training programs; ultimately resulting in innovative strategies to ensure quality learning outcomes and the advancement of university-level blended teaching mandates. This qualitative case study explored how twelve Caribbean lecturers experienced and navigated the teaching process in …

Bayesian Linear, Heteroskedastic, Multilevel, And Dynamic Models For Assessing The Effects Of Policy Uncertainty, Green Finance, Innovation, And Environmental Stringency On Sustainable Economic Growth In Oecd Economies, Md Qamruzzaman, Abdulrahman Alomair, Abdulaziz S. Al Naim, Sylvia Kor

Student Publications [Scholarly]

This study analyzes how policy uncertainty, green finance, green innovation, and the stringency of environmental policy affect sustainable economic growth in OECD member countries from 1996 to 2023. Given the growing evidence that advanced economies are facing structural lock-ins, a lack of coherent policy credibility, and insufficient financial and innovative capabilities, the current study integrates these factors into a coherent empirical framework that continues to prevent disintegration in the current literature. Using environmentally adjusted multifactor productivity as a proxy for green economic growth, the analysis employs a panel of Bayesian econometric models that include linear, heteroskedastic, multilevel, random-effects, and panel …

Assessing Future Drought Scenarios In Rangpur, Bangladesh Using Cmip6 Climate Projections And Drought Indices, Mijanur Rahman, Hossain Al Mahbub, Mst Sanjida Alam, Janifer Alam, Nusrut Sharmin, Md Naim Molla

Student Publications [Scholarly]

Climate-induced drought has become a growing concern across South Asia as rising temperatures and monsoon variability intensify hydroclimatic stress. This study evaluates historical (1979–2014) and future (2015–2100) hydroclimatic conditions in Rangpur using observed data and CanESM5 projections for three CMIP6 scenarios (SSP1-1.9, SSP2-2.6, SSP5-8.5). Multi-scale Standardized Precipitation Index (SPI) and Standardized Precipitation Evapotranspiration Index (SPEI) were applied to detect droughts, while Tmax and Tmin Z-scores quantified heat anomalies and compound drought–temperature events. Historical records show strong rainfall variability with no significant long-term trend, but significant warming particularly in Tmin indicating increasing evaporative demand. Future projections reveal moderate precipitation increases (+ …

Mtorc2-Nav1.2 Signaling Drives Early Hyperexcitability In Alzheimer’S Disease Mouse Model, Nolan M Dvorak, Jeffrey L Noebels

Faculty, Staff and Students Publications

Hyperexcitability is a biomarker of early-stage Alzheimer’s Disease (AD) and hastens cognitive decline later in its course. Mechanistic target of rapamycin (mTOR) signaling contributes to the slope of this trajectory, as evidenced by early increased brain expression and the rescue of hyperexcitability by genetic deletion of mTOR complex 2 (mTORC2); however, a molecular mechanism directly linking mTOR signaling to membrane hyperexcitability in early-stage AD remains elusive. Here, we show that hyperactive mTOR signaling stimulates the voltage-gated Na+ channel 1.2 (Nav1.2), a previously identified downstream phosphorylation target of mTORC2 and a key regulator of membrane electrogenesis. Augmented Nav1.2 channel function induced …

Evaluation Of A No-Code Ai Model For Detecting Periapical Radiolucencies: Impact Of Anatomical Region On Diagnostic Performance, Manal Hamdan, Kevin W. Yu, Marguerite Miller, Stephanie J. Sidow, Zaid Badr, Sergio E. Uribe

School of Dentistry Faculty Research and Publications

Background

To develop a no-code artificial intelligence (AI) model for the detection of apical radiolucent lesions and to assess how lesion location influences the model’s diagnostic performance.

Methods

312 periapical radiographs were retrospectively collected, each accompanied by a corresponding cone-beam computed tomography (CBCT) scan obtained within six months and a radiology report authored by board-certified oral and maxillofacial radiologists. These reports served as the reference standard, and all findings were cross-verified by the primary investigator through CBCT review. The dataset included 181 images with at least one apical radiolucent lesion and 131 lesion-free controls. Using the no-code AI platform LandingLens …

In-Hospital Mortality Patterns And Readmissions In Patients With Chronic Obstructive Pulmonary Disease: An Analysis Of The Role Of Pulmonary Hypertension, Saad Afzal Khan, Trishna Parikh, Adishwar Rao, Akriti Agrawal, Aarohi Parikh, Farah Kazzaz, Sarah Shin, Harry Karmouty-Quintana, Maulin Patel, Kha Dinh, Bela Patel, Bindu Akkanti

Faculty, Staff and Student Publications

Chronic obstructive pulmonary disease (COPD) may be complicated by pulmonary hypertension (PH). We aimed to understand the impact of PH on in-hospital mortality and quantify the 30-day readmission rate among patients with COPD. For this cross-sectional study, we used the Nationwide Readmissions Database from 2017-2020 to identify adults ≥18 years with COPD. Patients were stratified according to PH diagnosis. Baseline characteristics between groups were compared using the Pearson chi-square test and two-sample t-test. Predictors of in-hospital mortality were determined using multivariate logistic regression analysis adjusted for demographics and confounders. The 30-day readmission rate and prevalence of PH subgroups by baseline …

Exploring Burnout Among Ncaa Collegiate Athletes: The Impact Of Gender, Sport, Seasonal Demands, And Other Contributing Factors, Anneliese Wong

Undergraduate Honors Theses

The purpose of this study was to examine burnout among NCAA Division I student-athletes at one mid-sized University in the Rocky Mountains region of the United States and determine whether differences existed based on gender, sport type, competitive season stage, and burnout dimension. A quantitative, cross-sectional survey design was used and data was collected from 76 student-athletes across 11 varsity sports. Burnout was assessed using items adapted from the Athlete Burnout Questionnaire (ABQ; Raedeke & Smith, 2001), along with additional items assessing fatigue and seasonal experiences.

Descriptive results showed the student-athletes reported the highest mean level of physical burnout, followed …

Development Of A Standardized Evidence-Based Onboarding Process For Primary Care Providers In A Rural Health Setting, Corrie Goodier

Doctoral Scholarly Projects & Capstones

Primary care in the United States continues to face a critical provider shortage. This shortage is especially elevated in the rural regions of the country and is exacerbated by longstanding issues with subpar onboarding and high turnover rates. Failure to retain advanced practice providers in rural primary care settings further diminishes patient access to services, negatively impacts continuity of care, and complicates efforts to maintain patient trust in the nation’s delicate healthcare system.

Improved provider orientation and support processes within rural healthcare systems have the potential to increase satisfaction rates and productivity. The purpose of this DNP scholarly project was …

Study Of Fast Switching Metastable-State Photoacids And Controlled Drug Release From Polycaprolactone (Pcl) Vascular Scaffold, Rana Salman Abbood Abbood

Theses and Dissertations

Metastable-state photoacid (mPAH) has become a common tool for controlling and driving chemical processes with light. mPAHs with fast reverse reactions are desirable for precise temporal control or generating quick pulses of proton concentration. In this work, different approaches towards fast reversing mPAHs are studied. Experimental and computational results showed that stabilizing the charge–transfer intermediate is an effective way to increase the rate. A novel mPAH with a reverse reaction ≈500 times faster than the most widely used mPAH in methanol has been developed. Another water-soluble mPAH exhibited a reverse reaction with a rate constant of 7.8 s−1, the fastest …

Gender Gap In Returns To Publications, Piotr Śpiewanowski, Ivan Stetsyuk, Oleksandr Talavera

All Works

Gender equity in science depends not only on who participates in research, but also on how their work is rewarded. We examine gender gaps in monetary returns to research productivity, pay, and credit attribution using a novel dataset linking salary and publication records for professors at U.S. public universities. While our main contribution shows that there is no robust evidence of a significant gender gap in monetary returns to publications, we uncover substantial heterogeneity across disciplines and authorship structures. Women in medical and health sciences experience a negative gap in returns of 10.7% relative to men for equivalent research output. …

How Leaders Build Employee Trust In Artificial Intelligence: Voice Opportunities, Humility, And Trust Transfer, Jack Mcguire, David De Cremer, Devesh Narayanan

Research Collection Lee Kong Chian School Of Business

Artificial intelligence is increasingly central to organizational work, yet employee trust in AI remains fragile. Although prior research has primarily explained trust in AI through technological characteristics such as transparency, reliability, and accuracy, we argue that trust in AI is also shaped by the social context in which employees encounter these systems. Drawing on affect-as-information theory and social information processing theory, we develop and test a model in which leader-provided voice opportunities reduce employees’ negative affect about AI-related work experiences, thereby enhancing perceptions of leader trustworthiness and, in turn, trust in AI. We further propose that this indirect effect depends …

Improving Nurse Confidence And Perceived Readiness For Early Code Blue Response: A Quality Improvement Project, Elexia Butler, Annette Sotelo Rodriguez, Paulene Rones, Evangelyne Vue

ELMSN E-Portfolio. A collection of Scholarly and Creative Works

Improving Nurse Confidence and Perceived Readiness for Early Code Blue Response

Purpose

In many acute care units that are predominately dealing with chronic conditions, cardiac arrest is a low frequency, high stakes event. The purpose of this project is to improve early cardiac arrest response by increasing nurse confidence and perceived readiness to initiate high-quality CPR prior to Rapid Response Team (RRT) arrival.

Background

Over the past three years, there has been a significant increase in Code Blue events on the Surgical Acute Telemetry Unit. Initial management observations noted that staff response lacked clear role delineation, immediate pulse identification, and …

Ambulatory Blood Pressure Variability In Prediction Of Target Organ Injury: The Ship Ahoy Study, Coral D Hanevold, Jang Dong Seo, Stephen R Daniels, Bonita E Falkner, Michael A Ferguson, Joseph T Flynn, Julie R Ingelfinger, Philip R Khoury, Marc B Lande, Kevin E Meyers, Mark Mitsnefes, Joshua Samuels, Elaine M Urbina

Faculty, Staff and Student Publications

Background: Ambulatory hypertension is associated with elevated left ventricular mass index (LVMI), cardiac dysfunction, and increased arterial stiffness in adolescents. Whether the addition of measures of BP variability improves the prediction of subclinical cardiovascular target organ damage (TOD) over mean BP measures is not known.

Methods: We assessed clinic and ambulatory BP (ABP), anthropometrics, and TOD in 397 adolescents. ABP means standard deviation (SD), BP, and heart rate (HR) dipping were calculated; coefficients of variability (CV) were calculated (SD/mean) to assess ABP variabilities. Measures of TOD included LVMI, left ventricular hypertrophy (LVH), LV systolic shortening, LV diastolic function (e'/a'), and …

The Downstream Effect Of Gender Bias On Academic Performance And Career Aspirations Amongst Female Students In Stem Via Gender-Professional Identity Integration (G-Pii), Chi-Ying Cheng, Shuna Shiann Khoo, Shih-Fen Cheng, Yeow Leong Lee, Vandana Ramachandra Rao

Research Collection School of Social Sciences

Background Gender imbalance in STEM, characterized by a significant underrepresentation of women, remains a significant challenge. Although gender bias is a well-known contributor to women’s attrition from STEM, the psychological mechanisms linking gender bias to departure are less well understood. Our research investigates early antecedents of attrition and the psychological processes that precede leaving the STEM pathway in tertiary education. Drawing upon identity integration research, we propose that perceived gender bias exerts undermines female STEM students’ academic performance and career aspirations by reducing their Gender-Professional Identity Integration (G-PII), a construct that captures individual differences in the perceived compatibility between a …

A Trait-Based Thermal Risk-Index Framework Integrating Stage-Structured Insect Demography, Host Resources And The Next-Generation Matrix, Komi Mensah Agboka, Luca Rossini, Bonoukpoè Mawuko Sokame, Quinto Juma Meltus, Juliet Onditi, Abdelmutalab G.A. Azrag, Elfatih M. Abdel-Rahman

All Peer-Reviewed Publications

The biology and population dynamics of terrestrial arthropods are strongly influenced by environmental conditions, particularly temperature, but thermal responses alone do not determine whether a population can establish when development depends on host resources. Here, we extend an existing physiologically based risk-index framework by explicitly coupling stage-structured insect demography with host-resource dynamics and deriving the resulting population-level invasion threshold through the Next-Generation Matrix (NGM) approach. The formulation integrates temperature-dependent development, fecundity and mortality across egg, larval, pupal and adult stages with host-resource production and depletion, yielding the basic reproduction number (R0[jls-end-space/]) as a mechanistically interpretable risk index, where (Formula presented) …

Producer Organizations, Productivity And Sustainable Intensification Practices In Oil Palm Production, Martin Paul Tabe-Ojong, Abebayehu Girma Geffersa, Kibrom T. Sibhatu

All Peer-Reviewed Publications

Oil palm production is expanding in traditional farming and forested areas, especially in West and Central Africa around the Congo Forest Basin and mostly characterized by declining yields and yield gaps. Due to typically non-binding land access, independent producers tend to prioritize extensification over intensification, which has negative environmental consequences. Sustainable intensification (SI) of smallholder production is a guiding paradigm that aims to increase yields while minimizing negative environmental impacts. In this study, we examine the relationship between producer organizations (POs), sustainable intensification practices (SIPs), namely mulching and intercropping, and oil palm yields in Cameroon. We estimate actual and counterfactual …