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EFFECTS OF MATCHING IMAGES OF NATURAL AND BUILT ENVIRONMENTS AND HUMAN MUTILATION ON IMPULSIVE BEHAVIOR: A SYSTEMATIC REPLICATION OF HURTADO-PARRADO ET AL. (2023)
Get PDFFlora et al. (1992, 2003) found that intense noise or pain caused by cold pressor procedure increased the number of impulsive responses (choice of a smaller-sooner reinforcer over a larger-later reinforcer) when presented concurrently with a choice task. Hurtado-Parrado et al. (2023) and Orozco-Barrios (2023) recently conducted systematic replications using aversive visual stimuli via a matching-to-sample task, but the results were inconsistent in reproducing the disruptive effect on self-control behavior reported by Flora et al. In a separate line of research, Berry et al. (2014, 2015) demonstrated changes in impulsive behavior with simple and brief exposure to images of Natural and Built environments. It thus appears that the difficulties to reproduce the effect of aversive stimulation on impulsive choice is related to the specific stimuli implemented. The present study aimed to systematically replicate Hurtado-Parrado et al.’s (2023) protocol to evaluate the effects of matching the same images implemented by Berry et al. on impulsive responses of college students. The same aversive images used by Hurtado-Parrado et al. (images of mutilation from the International Affective Picture System, IAPS) were included for comparison purposes. A single-case changing conditions design was implemented, which replicated Orozco-Barrios’ but added stability criteria. Four conditions were configured. One with no matching of images (No-Images), and three depending on the type of image matched, i.e., No-Images, Natural Environments, Built Environments, and IAPS Unpleasant. Results indicated that (a) only three participants showed preference for the self-control option and one indifference in the No-Images condition. The rest preferred the impulsive option, (b) all participants, except one, did not change their choice pattern when they transitioned from the No-Images condition to the first treatment condition (either matching Unpleasant, Built or Natural images); (c) five out of six participants who showed impulsive preference during the No-Images condition maintained the same choice pattern during all treatment conditions, and two out of three participants who showed self-control preference also maintained their preference; (d) participants who showed self-control preference during the No-Images condition showed a somewhat staggered pattern of increasing percentage of correct matching across conditions; and (e) most participants maintained correct matching responses above 50% across all conditions. Overall, these findings indicate the disruptive effect of self-control choice reported by Flora et al. was not reproduced using visual stimulation. The possible role of unplanned motivating operations, insensitivity to changes in the task due to rule-governed behavior, and not sufficient exposure to the overall rates of reinforcement associated with the self-control option are discussed
THE IMPACT OF COMMUNITY FORESTRY ON THE GENERAL AND SPECIFIED RESILIENCE OF COMMUNITIES AND HOUSEHOLDS IN NEPAL
No full textCommunity forestry as an approach to forest management has gained popularity in recent decades as a response to the failures of top-down, centralized forest policies. The shift from state-controlled forests to community forestry was aimed at achieving desired environmental and socio-economic outcomes in the forest management process. Community forestry is frequently posited as a promising forest management model for achieving ecological sustainability and community well-being. Although extensive literature exists that covers various aspects of community forestry, studies on the performance of community forestry programs in the face of unpredictable events such as climate change impacts and earthquakes are limited. In Nepal, for instance, community forestry programs have been implemented since the late 1970s and flourished after the adoption of the Forest Act of 1993. However, the impacts of these programs on the resilience of communities to various drivers of change have received little attention. To address these gaps, this dissertation employed a mixed methods approach in analyzing the impact of Nepal’s community forestry program on the general resilience of forest-dependent communities, as well as their specified resilience to the 2015 earthquake. Data for the qualitative component of the study were generated through the review of documents, as well as interviews with 27 purposively sampled key informants from two rural communities in the Gorkha district of Nepal, whereas quantitative data were generated through the administration of a survey questionnaire to 237 households who were selected using the systematic random sampling technique. Data were collected from November 2019 to March 2020.The results from the community level analysis revealed that the shift towards the community forestry program in both communities was triggered by the perception of ecological crises and facilitated by the existence of enabling policy conditions as well as the role of external forest organizations. The analysis of the impacts of the community forestry program on community resilience outcomes revealed variations across different forms of capital assets, with similarities and differences between the two communities. While natural capital, social capital, human capital were reported to have increased in both communities, the effect of community forestry on physical capital was found to be moderately positive. Regarding economic capital, the implementation of the community forestry program resulted in positive and negative outcomes on both communities, but the overall effect seemed to be moderately positive. Regarding specialized resilience outcomes, the community forestry program had a positive impact on community resilience to the 2015 earthquake. The community forestry program played various roles in community earthquake resilience, including enhanced access to timber for housing construction, and enhanced linking social capital for the mobilization of external resources. The results from the household level analysis showed that ethnicity and household’s prior involvement in forest organizations were significant predictors of household participation in the community forestry program but past household assets did not predict participation. Ethnicity and participation in the community forestry program were also the most important predictors of outcomes of the program, as measured by current levels of assets. Each of the past household assets and socio-demographic variables was a significant predictor of at least one of the current assets, but prior involvement in forest organizations did not predict any of the current assets or changes in assets. Regarding household resilience to the 2015 earthquake, household participation in the community forestry program also had a significant positive effect on two of the three dimensions of earthquake resilience, whereas past bridging capital and past physical capital each had a significant positive effect on the three earthquake resilience dimensions. Consistent with the community resilience framework, the results lend some support to the hypothesis that capital assets and institutions, coupled with the role of various community attributes, are important predictors of the process and outcomes of community resilience to drivers of change. Participation in community forestry programs provides an important mechanism for building general and specified resilience in forest-dependent communities. As global climate change policy has shifted towards community-based adaptation in recent decades, this study shows the potential for community forestry to serve as an entry point for global climate change policy through its contributions to community capacity for adaptation to various drivers of change
DESIGN, ANALYSIS, AND OPTIMIZATION OF RECONFIGURABLE INTELLIGENT SURFACES FOR WIRELESS COMMUNICATIONS
No full textNext-generation wireless technologies are being actively researched to meet the growing demands for higher data rates, massive connectivity, enhanced reliability, and extended coverage. Recently, reconfigurable intelligent surfaces (RISs) and extremely large antenna arrays (ELAAs) have garnered significant attention as new physical-layer transmission technologies capable of achieving unprecedented spectral and energy efficiency gains. Consequently, RIS and ELAA are considered as promising key enabling technologies for the sixth-generation (6G) and future wireless standards.This dissertation investigates RIS and simultaneously transmitting and reflecting (STAR)-RIS assisted wireless communications, emphasizing design, optimization, and analysis across various practical settings. It presents wireless channel modelling techniques, system design aspects, fundamental performance limits/metrics, including outage probability, average achievable rate, average symbol error rate (SER), diversity order, computational complexity, and algorithmic foundations. This doctoral research also develops algorithms for optimizing RIS/STAR-RIS phase shifts and transmit power allocation in multi-user massive multiple-input multiple-output (MIMO) systems. Moreover, this dissertation characterizes unique propagation characteristics of ELAAs, and thereby impacts of visibility regions (VRs) and spatial non-stationarity in extra-large (XL) RIS communication set-ups with XL-massive MIMO base stations (BS) are analyzed.The dissertation begins with a fundamental performance analysis of RIS-assisted systems operating over Nakagami-m fading channels. It quantifies optimal phase-shifts to maximize received signal-to-noise ration (SNR) and derives the probability distribution of the SNR. The findings include closed-form expressions for outage probability, average SER, and achievable rate, demonstrating that these metrics improve as the number of RIS reflective elements increases. The study also reveals that the achievable diversity order scales linearly with the number of passive RIS elements, resulting in significant diversity gains without additional radio-frequency (RF) chains. Further investigation into STAR-RIS systems with discrete phase-shifts highlights the performance under different protocols, such as energy splitting (ES), mode switching (MS), and time splitting (TS), considering both unicast and multicast transmissions. The analysis demonstrates that employing four-bit phase-shift quantization significantly narrows the performance gap between discrete and continuous phase-shifts. Additionally, it is found that the average achievable rate and SER reach saturation levels at high transmit SNRs, influenced by power allocation coefficients at the transmitter. The dissertation also presents an achievable rate analysis and RIS phase-shift optimization for multi-cell RIS-aided massive MIMO, with for imperfect channel state information (CSI), co-channel interference, and spatially correlated fading. A statistical CSI-based transmit power allocation algorithm is proposed, reducing channel estimation overhead and ensuring user fairness. In exploring STAR-RIS aided multi-user massive MIMO systems, statistical CSI-based STAR-RIS phase-shift and transmit power optimization techniques are used to maximize composite channel gains and ensure fair user rates. The study quantifies the impacts of CSI imperfections, residual interference, and spatially correlated fading. Lastly, the effects of visibility regions in XL RIS setups are examined, deriving achievable user rates and employing phase-shift optimization to maximize user channel covariance. A max-min power allocation algorithm is utilized to address near-far user effects, ensuring system-wide user fairness. Overall, this dissertation provides comprehensive insights and advanced optimization techniques for enhancing RIS and STAR-RIS technologies in wireless communication systems
THE POWER OF LABELS: HOW CERTIFICATION LABELS AFFECT CONSUMERS’ PURCHASE INTENTIONS AND WILLINGNESS TO PAY HIGHER PRICES FOR PLANT-BASED NON-FOOD PRODUCTS
No full textAs more and more consumers are growing environmentally conscious, businesses are leveraging ways to showcase their sustainability efforts in their products by obtaining certifications and putting these labels in product packages. As certifications are rigorous and hard to obtain, obtaining certifications is a means to spearhead the sustainability momentum. However, academic research in certification, especially with non-food products made from plants, is limited. Hence, this dissertation study focuses on the influence of certification labels in consumers’ purchasing behaviors by specifically looking at consumers’ purchase intentions and willingness to pay higher prices for plant-based non-food products with certification labels. In addition, this dissertation study also explores the mediating role of perceived efficacy and perceived eco-friendliness on consumers’ purchase intentions and willingness to pay higher prices. Moreover, subsequent study will also examine the impact of informative certification labels.Across three experimental scenarios using household products such as multipurpose cleaners and laundry detergents, it was found that consumers show higher purchase intentions and greater willingness to pay higher prices for products with certification labels compared to products without certification labels. Similarly, it was found that consumers are willing to pay higher prices for plant-based products compared to non-plant-based products. The mediating relationship of perceived efficacy is observed with its effect being the greatest for plant-based and certified products compared to not-certified products whether it is plant-based or not. With regards to perceived eco friendliness, the research showed that consumers perceive plant-based and certified products as more eco-friendly than non-plant-based products despite their certification status leading to greater purchase intentions and willingness to pay higher prices. In study 3, the role of informative certification labels was investigated. Specifically, it was found that plant-based and certified products with informative certification labels (compared to plant-based and certified products without informative certification labels) demonstrated higher perceived efficacy leading to purchase intentions and willingness to pay higher prices. The findings from this dissertation benefit both academic marketing researchers and marketing managers. Manufacturers of plant-based household products can leverage the advantages of certification labels as a competitive edge and be able to remove doubts and confusions that consumers have towards plant-based non-food products by obtaining certifications
COMPARISON OF PARENT CONDUCTED TRIAL-BASED FUNCTIONAL ANALYSES IN NATURAL AND CONTRIVED SETTINGS
No full textThe trial-based functional analysis (TBFA) has recently emerged for practitioners as a method to determine the function(s) of challenging behavior in natural contexts such as the classroom or residential settings. Comparisons between TBFA and other functional analyses (FA) results have shown high correspondence when identifying the function(s) of challenging behavior. Currently, the TBFA has mainly been conducted in classroom settings with teachers or paraprofessionals. Although important in educational contexts, it is unknown if the TBFA would identify the same function(s) of challenging behavior across different settings, thus possibly limiting its utility. The purpose of the current study was to compare the results of a parent-conducted TBFA in the child’s home and at a university-based autism clinic. TBFA results found minimal differences regardless of the setting, suggesting that the TBFA procedures can be conducted in clinics or at home while producing similar findings. Social validity results for two of the three families were identical across settings, suggesting they had no preference for where to conduct the TBFA or any of the conditions. However, one caregiver preferred the escape and tangible conditions over the attention condition. The same caregiver also preferred the home TBFA over the clinic TBFA. High procedural integrity was reported on the author’s ability to facilitate the TBFA procedures with the families. Taken together, these data will help to guide and inform future treatment recommendations for families
PROCESS DEVELOPMENT, CHARACTERIZATION AND STORAGE STUDY OF MUNG PROTEIN BASED NON-DAIRY YOGURT
No full textThis thesis investigates the viability of mung bean-based yogurt enriched with protein isolates as a dairy yogurt alternative. Through extensive analysis, Treatment 1 (1.5% cassava flour with oil-based mung bean yogurt) emerged as a promising option, exhibiting similar lightness in color to dairy yogurt. Moreover, Treatment 4 (1.5% cassava flour without oil-based mung bean yogurt) demonstrated the longest shelf life of 91 days based on microbial analysis, indicating the potential of oil-free formulations to delay spoilage and enhance shelf life. Texture characteristics, particularly hardness, and adhesiveness, were comparable to dairy yogurt in Treatment 1 and Treatment 2 (2% cassava flour with oil-based mung bean yogurt), with Treatment 3 (2.5% cassava flour with oil-based mung bean yogurt) showing similar adhesiveness to control yogurt. However, observations revealed a cracking defect in yogurt samples prepared without oil, escalating with storage time, supported by SEM images highlighting irregular textures in Treatment 6 (1.5% cassava flour without oil-based mung bean yogurt).Furthermore, the study developed artificial neural network (ANN) models for predicting shelf life, with physicochemical parameters (acidity, pH, and color values) proving to be the most effective inputs, yielding an r2 value of 0.9984. In comparison, microbial and sensory-based ANN models exhibited lower r2 values of 0.9015 and 0.9064, respectively. This underscores the importance of incorporating comprehensive data in developing accurate prediction models, advocating for further research to delve into additional yogurt properties for enhanced model realism. In conclusion, this thesis contributes to the understanding of mung bean-based yogurt formulation and storage, highlighting the potential of oil-free formulations for prolonged shelf life and identifying key physicochemical parameters for precise shelf-life prediction. Future endeavors should focus on collecting real-world data to refine prediction models, aiding yogurt manufacturers in ensuring food safety and facilitating informed consumer decisions regarding product shelf life
PHOSPHORUS-ALTERED PARASITE-HOST INTERACTIONS EXAMINED AT MULTIPLE SCALES
No full textShifts in the availability of nutrients in freshwater ecosystems can have wide-ranging impacts on parasite-host interactions. However, the mechanisms that drive these impacts are poorly understood, in part due to the challenges involved in directly observing parasites. Daphnia-microparasite systems have emerged as a common model system to examine the ecology and evolution of parasites, with a great diversity of parasitic strategies seen across parasite taxa. Daphnia are important herbivores in freshwater systems, which makes them ideal organisms to study to understand the impact of changes in freshwater primary production. Since freshwater systems are often phosphorus limited and P is linked to algal quantity and quality, my work here focuses on the effect of P availability on Daphnia-microparasite systems. Here, I chose to study the microsporidian Hamiltosporidium tvaerminnensis and the bacterium Pasteuria ramosa due to their differing infection strategies, examining H. tvaerminnensis at the host population scale, and P. ramosa at the level of the individual host. Hamiltosporidium tvaerminnensis infects its host via both vertical transmission (to hosts’ offspring) and horizontal transmission (through the ingestion of spores released by dead hosts). Previous work on individually housed Daphnia suggests that high P Daphnia diets increase H. tvaerminnensis spore loads while reducing the competitive advantage (fecundity) of uninfected Daphnia relative to infected ones. However, it is unclear how these individual level effects scale up to the population level, where effects of P availability on host density may mediate the relationship between P and this parasite’s abundance. For my first study, I chose to explore how these effects scale up to affect transmission. I manipulated phosphorus availability in mesocosms seeded with 4 vertically infected and 4 uninfected Daphnia. After sixty days, I found significant positive relationships between algal P concentration and the prevalence, spore load, and total population size of this parasite. These results are consistent with previous work suggesting that competition from uninfected individuals can be an important driver of prevalence for this parasite, and that nutrients can shift the outcome of that competition in ways that alter parasite populations. I also found a significant negative relationship between algal density and spore load. This result demonstrates one way that resource-consumer dynamics can influence how parasites move through systems. For my second study, I chose a mechanistic modeling approach at the level of the single host. The Dynamic Energy Budget framework explicitly and mechanistically models the flow of energy through an organism and has been applied to several parasite-host systems. Here, I focused on Pasteuria ramosa, which exclusively transmits horizontally. Previous work suggests that P. ramosa shows a great deal of trait plasticity, and I was interested in creating a model that could demonstrate that trait plasticity and its effect on parasite growth. My goal was to model the results of a previous study run on Daphnia in our lab, which showed acclimation to hosts fed at different P levels. I identified two potential parameters of a bacterial growth model, uptake rate and metabolic maintenance rate, that could covary and create separate strategies for the parasite—a high uptake, low efficiency strategy and a conservative, low uptake strategy. Each strategy, I predicted, would be more successful under different host diets. I then ran 30 day simulations with combinations of each parasite strategy and host diet. These simulations showed that, by varying uptake and maintenance rates, the observed trends in parasite acclimation could be modeled. These studies together demonstrate how P availability can affect host-parasite interactions at multiple scales, in parasites with multiple infection strategies. Given how widespread parasites and nutrient inputs are in natural systems, continued work is needed to detangle these complex relationships
UNDERSTANDING GEOGRAPHIC PROFILING: A SCOPING REVIEW
No full textThis scoping review delves into the breadth and depth of geographic profiling research, a technique rooted in criminology and forensic psychology for assisting law enforcement in identifying likely locations of criminal offenders. Stemming from principles of environmental criminology and spatial analysis, geographic profiling has garnered scholarly attention due to its potential in enhancing investigative strategies and aiding in criminal apprehension. The following review addresses whether geographic profiling research has experienced increased growth since its formalization in the late 1990’s to now by evaluating the characteristics of articles related to publishing (i.e., publishing rate over time, types of journals, and concentration of publishing between authors) while also evaluating the commonalities and broader narratives within the content published. This evaluation revealed geographic profiling as a relatively small scientific field attempting to gain traction in the realm of application and implementation amongst policing agencies. Furthermore, trends of methodological refinement, application hurdles, and future research recommendations are discussed within. Overall, this review underscores the need for interdisciplinary collaboration, innovation, and methodological rigor to address challenges and propel geographic profiling research forward