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ANALYZING THE DIRECTIONAL ASYMMETRIC IMPACT OF NET MIGRATION ON ECONOMIC GROWTH: A STUDY OF 72 INCOME CLASSIFIED COUNTRIES
No full textUsing neo-classical growth model, the paper analyzes the impact of net migration on economic growth for 36 developed and 36 developing countries, from 1980 to 2022. For analysis, FOD-GMM is employed. Using directional asymmetry, findings of the analysis reveal that the net migration have non-linear impact on economic growth. Alos, it is evident that effects of net migration is not the same for all countries. For developed countries net immigration raises income per capita, and for developing countries net emigration raises income per capita
USING THE TRANSTHEORETICAL MODEL TO UNDERSTAND MOUD PARTICIPANTS GOALS IN RURAL ILLINOIS.
No full textBackground: The opioid epidemic in the United States (U.S.) continues to be problematic. While the number of overdoses deaths have declined in recent, this is still a problem in the U.S. One of the recommended interventions to treat opioid-use disorder (OUD) is using Medications for Opioid-use Disorder (MOUD) to treat this. The Transtheoretical Model (TTM) is a public health model that can access an individuals readiness to change health behaviors. It is important to understand how individuals with OUD can move through the stages of TTM to access MOUD treatment in rural areas, and what barriers they face when trying to access MOUD treatment in rural areas.Methods: A case study was conducted in a rural Illinois region to understand current and/or past experiences individuals with OUD have had with MOUD in rural areas. Qualitative semi-structured interviews were conducted with individuals who have had experiences with MOUD in the selected rural areas to understand how they moved through the stages of change of MOUD, and what facilitators and barriers effected their movements through TTM. Results: A total of ten interviews were conducted. Eight were men, while two were women. All participants identified being white/Caucasian. Participants resided in the case study region. All participants disclosed being on Medicaid for insurance, while two discussed having Medicare as well. Themes from the interviews were stages of change at time of interview, movements through the stages of change, relapse, and experiences with MOUD treatment. Conclusions: The main facilitators and barriers that caused movements through TTM included opioid overdose experiences, legal issues, life changing events, lacking adequate supports and resources, and positive/negative experiences with MOUD treatment. While findings of the study were consistent with literature findings, there needs to be emphasis on looking at flexibility in delivery of interventions by MOUD treatment centers. Having different interventions to accommodate individuals could help with retention rates, while addressing barriers that prevent them from accessing treatment. Having a stronger understanding of treatment center practices could help with interventions. Future research should examine the possibility of utilizing peer-recovery coaches to coincide with treatment to see if it can offset barriers/concerns in rural areas
Seasonal Habitat Use, Capture Efficiency, Population Dynamics, and Physiology of Mudpuppies (Necturus maculosus) in an Urban Lake
No full textFreshwater habitats are among the most vulnerable environments on earth, with extinction rates higher than both terrestrial and marine habitats. Common mudpuppies (Necturus maculosus) are fully aquatic North American salamanders that have experienced population declines. Despite their large size and wide geographic distribution, much of their basic natural history and ecology is understudied. Utilizing modified minnow traps, I set 3988 traps baited with fathead minnows over 58 total trapping nights in Wolf Lake, Chicago, Illinois. I captured 129 individuals using traps and observed a significant decline in capture success above 14oC (0.003 mudpuppies/trap/night above 14oC and 0.05 mudpuppies/trap/night below 14oC) with a maximum temperature of capture of 20.5oC. In addition, during ice-free periods, I collected 72 mudpuppies by rock flipping during 31 rock flipping events and 140 person hours. Comparable to our trapping data, I found a significant decline in captures above 14oC (0.34 mudpuppies/person/hour above 14oC and 1.28 mudpuppies/person/hour below 14oC) with a maximum temperature of capture of 28.9oC. There was a significant difference in total length of mudpuppies caught in traps (mean TL= 24.1±0.8cm) and rock flipping (mean TL= 15.6±0.5cm). This finding indicates the need for multiple capture methods to describe population dynamics and presence of recruitment. I found that larger individuals were found rock flipping at a greater water depth (R=0.39, p=0.0016) but not necessarily a greater distance from shore (R=0.28, p=0.025), which is indicative of the anthropogenically disturbed habitat at Wolf Lake. I used non-lethal gastric lavage method to acquire and compare stomach contents across size classes. I used Non-metric multidimensional scaling (NMDS) to visually compare diet differences and Analysis of Similarities (ANOSIM) to determine diet similarities for abundance and volume of prey items. Size classes were divided by total length into: small (0-10cm), medium (10.5-20cm), and large (\u3e20.5cm). For abundance, 51% of the similarity was driven by amphipods and insects between small and medium mudpuppies, 59% was driven by amphipods and fish between small and large mudpuppies, and 59% was driven by fish and insect between medium and large mudpuppies. For volume, 57% of the similarity was driven by fish and crayfish between small and medium mudpuppies, 86% was driven by fish between small and large mudpuppies, and 56% was driven by fish between medium and large mudpuppies. Abundance and volume were driven by total length (p=0.001) with prey items all significantly different for abundance, and all prey items except isopods significantly different for volume. I also found amphibians in stomach contents with frogs (n=4) and a cannibalistic event were a 25.5cm individual consumed a 14cm individual. My findings suggest that mudpuppies are gape-limited, opportunistic feeders that consume a variety of prey items regardless of size. We implanted radio transmitters in twenty sub-adult to adult mudpuppies in March, 2017 and in seven sub-adult to adult mudpuppies in December, 2017 to analyze seasonal movement. Individuals were located every 16.3±0.3 days and median distance moved between tracking events was 3.7m. Further, 97% of all movements were less than 10m and all movements \u3e10m occurred between October-May (with the exception of two events). There was no significant difference between male and female movements (p=0.26) and sedentary behavior was observed following large movements. My findings were similar to movements observed in terrestrial salamanders where individuals remain in familiar territory or within home ranges (Stebbins and Cohen 1995). The largest movements were seasonal and near-shore habitats were utilized (greatest depth 4.3m). I used hormone analysis and acute metabolic response due to temperature to analyze what is driving seasonal movements. Female hormone concentration (estradiol) did not vary across seasons (spring, summer, and winter) and males were only caught in the spring. This may be due to nest guarding behavior in females and males vacating the breeding grounds after breeding. Mass-specific oxygen consumption (mgO2/kg/hour) was highly variable with a 10.3% increase from 12.7oC to 24.3oC, a 31.9% increase from 12.7oC to 15oC, and a 16.4% decrease from 15oC to 24.3oC. I calculated a Q10 temperature coefficient of 1.4 across my study temperatures. This pattern shows limited response to acute temperature changes and can be explained by the wide latitudinal distribution of mudpuppies and the large seasonal difference in water temperature at Wolf Lake (~3oC-30oC). My study conveys the importance of extensive sampling periods for mudpuppies to accurately predict their population status due to seasonal activity patterns, difficulty of capture, and overall cryptic appearance and behavior. My findings show the need for near-shore habitat protection in conservation efforts for mudpuppy prey habitat and breeding locations
GRATITUDE AND WELL-BEING OF UNIVERSITY STUDENTS IN THE UNITED STATES AND SOUTH KOREA
No full textGratitude has become one of the most central concepts in positive psychology and counseling. Most of all, gratitude positively influences the well-being of human beings. Despite growing interest in dispositional gratitude and well-being in cultural frameworks, these relationships have not been systemically compared across cultures. Thus, in order to investigate the cross-cultural similarities and differences in dispositional gratitude and well-being, this study systemically examined the associations between dispositional gratitude and well-being indicators, including subjective well-being such as life satisfaction, positive and negative affect, and psychological well-being such as purpose in life, autonomy, personal growth, environmental mastery, positive relationships with others, and self-acceptance, of university students in the United States and South Korea, representing each individualistic and collectivistic culture. Moreover, increased knowledge of the moderators provides a deeper understanding of the relationship between gratitude and well-being in cultural contexts. Thus, this study also investigated the moderating effects of indebtedness on the relationship between dispositional gratitude and subjective well-being in two countries. This study utilized a web-based survey and included a valid sample of 307 American and 306 Korean college students. The independent samples t-test analyses indicated that American and Korean university students differed significantly in the mean levels of all study variables. Specifically, compared to the American participants, Korean participants reported higher mean levels of dispositional gratitude, life satisfaction, positive affect, negative affect, total score of psychological well-being, environmental mastery, positive relations with others, purpose in life, and self-acceptance. On the other hand, American participants reported higher mean levels of autonomy and personal growth than Korean participants. Second, the results from Pearson coefficients revealed that dispositional gratitude was significantly associated with all indicators of subjective and psychological well-being in both the United States and Korea. Third, the results from Fisher Z analyses showed that the differences in the associations of dispositional gratitude with negative affect, total psychological well-being score, environmental mastery, and personal growth between American and Korean participants were statistically significant. These associations of American university students were significantly more robust than those of Korean university students. Lastly, the results from multiple hierarchical analyses indicated that indebtedness did not moderate the relationship between dispositional gratitude and three subjective well-being indicators for American and Korean college students. This study is also meaningful in that it provides insight into how counselors or educators should intervene with their clients with gratitude interventions within cultural contexts. Moreover, these results could also stimulate future empirical work to replicate and extend more representative and larger samples from different cultures and other moderators. Lastly, limitations and future research directions are discussed
USING A HYPOTHETICAL PURCHASE TASK TO INFORM THE SELECTION OF TERMINAL REINFORCERS IN A TOKEN ECONOMY
No full textAN ABSTRACT OF THE DISSERTATION OFMarty D. Price, for the Doctor of Philosophy degree in Psychology, presented on November 13, 2024, at Southern Illinois University Carbondale. TITLE: USING A HYPOTHETICAL PURCHASE TASK TO INFORM THE SELECTION OF TERMINAL REINFORCERS IN A TOKEN ECONOMY MAJOR PROFESSOR: Dr. Eric Jacobs Token economies are among the most used techniques in applied behavior analysis across a variety of locations and diagnoses. However, most of the research in token economies is targeted at the economy and how it functions, and little attention is paid to the methods for backup reinforcer selection. Often simple interviews or standard preference assessments are used to determine which items are selected, with the values assigned to those items arbitrarily selected by the clinician. Methods within behavioral economics can be used to address this oversight, specifically hypothetical purchasing tasks and demand curve analysis. For this study, four participants with intellectual and/or developmental disabilities will be asked to complete two experiments using hypothetical purchasing tasks, the first with fixed incomes and variable prices and the second with variable incomes and fixed prices. A third experiment will introduce a simulated token economy by introducing a work component necessary to earn tokens to spend on backup reinforcers. Therefore, the purpose of the proposed research is to assess the efficacy of using hypothetical purchasing to inform the creation of a token economy for the treatment of behavioral problems in individuals with intellectual or developmental disabilities.Keywords: hypothetical purchasing, token economy, developmental disabilities, assessmen
USING HUMAN CELL LINE MODELS TO UNDERSTAND THE MECHANISMS OF POLG MITOCHONDRIAL DISEASE AND MEHP-INDUCED MITOCHONDRIAL TOXICITY
No full textMitochondrial DNA (mtDNA) is an essential component of mitochondria and consists of 13 protein coding genes which encode 13 subunits of the oxidative phosphorylation (OXPHOS) machinery. According to widely accepted theory, the mitochondrion was derived from an alpha-proteobacteria which was engulfed by an early eukaryotic cell and eventually evolved into the organelle through a process called endosymbiosis. Most of the proteins located in mitochondria are encoded by nuclear genes. Through the endosymbiotic process most of the bacterial genes were transferred to the nucleus leaving a small genome inside mitochondria (mtDNA). Looking at the DNA replication machinery of mtDNA, the components share structural similarity with viral replication machinery making it vulnerable to drugs targeted for antiviral therapy. Additionally, mitochondrion is one of the primary sources of cellular reactive oxygen species (ROS) production. Different chemical compounds and environmental toxicants can disrupt mitochondrial function resulting in increased ROS production leading to mitochondrial damage. Damaged mitochondria are detrimental to cellular health as the ROS produced by mitochondria can damage other cellular components. To protect the cell from damaged mitochondria, a specialized autophagy process is required called mitophagy which is responsible for clearing damaged mitochondria through the autophagic pathway. Moreover, damaged mitochondria can activate apoptotic signaling leading to cell death. To investigate the role of replication machinery on mitochondrial function, we utilized a cell line harboring a mutation in the POLG gene leading to a change in the amino acid position 955 from Tyr to Cys (Y955C) situated at the active site of the mitochondrial DNA polymerase, Polγ (chapter 2). We observed reduced growth rate, reduced mtDNA copy number, and increased sensitivity to the mtDNA toxicant dideoxycytidine (ddC) in the variant cell line relative to control. Additionally, there were reduced mtDNA nucleoids which support decreased mtDNA copy number. One and two-dimensional agarose gel electrophoresis analysis showed an increased abundance of Y955C mtDNA replication intermediates and linear molecules which likely result from double strand breaks due to replication stress. Moreover, the mtDNA encoded complex I subunit, NADH dehydrogenase subunit 3 and nuclear DNA encoded complex I subunit, NADH:ubiquinone oxidoreductase subunit B8 protein levels decreased in the variant cell line compared to control which indicates OXPHOS complex I activity and assembly is affected by the Y955C mutation. This indicates that dysfunction in mtDNA replication can affect mitochondrial function and cellular growth. Phthalates are a class of chemical compounds which are used as plasticizers. During the use of plastics, phthalates can leach out from the plastic and go inside the body. The detrimental effect of phthalate toxicity on mitochondrial function is reported in chapter 3 & 4. We explored the clearance of damaged mitochondria through PINK1-PARKIN pathway during MEHP exposure. MEHP exposure also affects mtDNA copy number in undifferentiated HepaRG cells. Also, one of the essential components of mtDNA replisome, MGME1 could be affected by MEHP exposure. This indicates that MEHP toxicity affects mitochondrial function and mtDNA copy number leading to mitochondrial damage which is likely cleared by the autophagy pathway. As mitochondria play an important role in apoptosis, the effect of MEHP exposure on the induction of cell death was assessed. During MEHP exposure, apoptotic cell death was observed, and apoptotic factors were induced. This indicate that acute MEHP toxicity disrupt mitochondrial function leading to autophagic clearance of mitochondria and induction of apoptotic cell death. Our observations explored the role of mitochondrial replication machinery in maintaining mitochondrial health and how disruption of mtDNA replication can affect mtDNA maintenance and cellular growth. Also, the toxic effect of MEHP exposure on mitochondrial function was observed which is evident by induction of mitophagy and apoptosis during exposure of MEHP. Insights from these studies help us to understand the mechanism of mitochondrial disease related to mutations in the mtDNA replication machinery and the consequence of environmental toxicant exposure on mitochondrial and cellular fate
COMMUNITY RESPONSE TO FLOODS IN THE CACHE RIVER WATERSHED OF SOUTHERN ILLINOIS: APPLICATION OF A PROPOSED FRAMEWORK FOR ASSESSING GENERAL AND SPECIFIED COMMUNITY RESILIENCE
Get PDFRecent years have seen increased awareness about the potential adverse impacts of climate change on hydrologic systems and human communities. The concept of community resilience – the capacity of communities to respond to drivers of change in a manner that maintains or improves upon community well-being – is widely recognized as a suitable framework for informing climate change adaptation policies. Emerging insights from the community resilience literature highlight the importance of the distinction between general resilience, which refers to the resilience of social-ecological systems to all kinds of drivers of change, and specified resilience, which is concerned with the resilience of social-ecological systems to particular drivers of change. While capital assets and institutions are generally considered to be the contextual factors shaping general resilience, the roles of these contextual factors in shaping specified resilience have not been adequately explored. To fill this knowledge gap, we developed a synthesized conceptual model that describes how community contextual factors influence the process and outcomes of community responses to specific drivers of change. This qualitative study was designed to test the proposed conceptual model by analyzing the responses of two rural communities (Belknap and Tamms) to floods in particular, and climate change impacts in general in the Cache River watershed of Southern Illinois. Both communities selected for the study have historical experience with flooding and consist of different population sizes. Hence, they are likely to have different levels of endowment of the assets and institutions that shape community resilience. Data for the study were collected through document review, as well as semi-structured interviews with 23 purposively sampled key informants representing various sectors of the local society (e.g. commerce, education, religion, local government). The data were analyzed using deductive coding in NVivo software based on analytical constructs derived from the proposed conceptual model. The results showed that communities in the Cache River watershed draw from a network of formal and informal institutions at multiple levels (local, state, national) in their responses to floods, although responses to other climate change impacts are less noticeable. Community capacity to respond to these impacts are also enabled by the availability of high levels of some capital assets (such as social capital), but also constrained by low levels of other community capital assets (such as economic capital and physical capital). Community assets and institutions also seemed to shape community perceptions and responses to future climate change scenarios where community relocation may be a viable response option. In all, our results provide rich insights on how community capital assets and institutions interact to either constrain or enhance the awareness, motivation, capacity, and opportunities that influence community responses to current and future drivers of change. Future research should seek to further refine and test this and related frameworks, as well as develop relevant indicators for further understanding the general and specified resilience of communities. With regard to policy, the results highlight the need for policies on climate change impacts and other disasters to move towards more targeted approaches to prepare communities to deal with specific threats in addition to those policies that focus on the general well-being and capacity of communities to deal with all kinds of drivers of change. Building the specified resilience of communities will require the utilization of existing scientific and non-scientific knowledge on the types of institutions and assets that are critical to community responses to the drivers of change under consideration in particular contexts
MAGNETOTRANSPORT PROPERTIES OF POLYCRYSTALLINE Mn_(3-x)Fe_xSn (x = 1, 2) THIN FILMS
Get PDFThe incredible progress of the microelectronics industry in the last several decades hasbeen primarily due to the progressive miniaturization and optimization of the MOSFET. However, the rate of this progress is becoming unsustainable by these means. Of several proposed replacements, one of the most popular ideas is to utilize electronic spin in logical processing. The discovery of Giant Magntoresistance (GMR) in layered thin film heterostructures and the subsequent development of Tunneling Magnetoresistance (TMR) devices revolutionized magnetic field sensing, which allowed magnetic domains in hard drives to get much smaller. This enabled hard drives to get denser, but because current charge-based devices are still much faster and smaller and require less energy to switch than magnetic domains, charge-based devices are still preferred for primary storage (RAM). The discoveries of Spin Orbit Torque (SOT) and Spin Transfer Torque (STT) have demonstrated that spin can be utilized for writing as well due to interactions between spin and the magnetization of a ferromagnet. Although magnetoresistive RAM (MRAM) has already been successfully implemented as a commercially available product, it remains small and expensive and is only used in specific applications. This is partially due to limitations of the individual constituent materials as spin filters or conductors, and partially due to incompatibility of adjacent crystal layers in a heterostructure. Many different types of mai terials have recently been identified as promising candidates for an optimized spin-based device. Manganese-based Heusler compounds constitute a large subset of these theoretically predicted materials due to their high perpendicular magnetic anisotropy (PMA), high curie temperatures, and low saturation fields, as well as their spin conduction, all with very similar crystal structures. In this work, I study magnetotransport and magneto-optical properties of Mn2FeSn and Fe2MnSn thin films and review properties of their parent compound Mn3Sn, which has been reported on extensively in the literature. My experimental methods involved a combination of homemade setups and sophisticated commercial tools. I may have observed a large topological Hall effect in a D019 Mn2FeSn thin film, and did observe a major substrate dependence on the properties of D019 Fe2MnSn thin films and a curious current dependence on the magnetoresistance behaviour in an Fe2MnSn thin film. This work emphasizes the sensitivity of Heusler alloy stoichiometry
SIMPLE SMALE FLOWS ON S3 USING EMBEDDED TEMPLATES WITH TWISTED BANDS
Get PDFWe study the linking structure of the attractor-repeller pairs in simple Smale flows on the 3-sphere in which the chaotic saddle set is modeled by four-band templates with twisted bands. This is a small step in an attempt to classify simple Smale flows on S³. We obtain three new theorems which illustrate that the dynamics of simple Smale flows are sensitive to half-twists in the bands of the embedded template. Haynes and Sullivan showed that the attractor-repeller pair a∪r in a simple Smale flow with chaotic saddle set modeled by embedded template U⁺ is either a Hopf link or a trefoil and meridian [19]. By placing a single half-twist in a selected band of U⁺, we obtain four new templates that model chaotic saddle sets. For simple Smale flows on S³ with chaotic saddle sets modeled by those templates, we find that such simple Smale flows are realizable and that a∪r must be a Hopf link, a figure-8 knot and meridian, a trefoil and meridian, or a cinquefoil and meridian
Microglial Piezo1 Mechanosensitive Channel as a Therapeutic Target in Alzheimer\u27s Disease
Get PDFMicroglia are the resident macrophages of the central nervous system (CNS) that control brain development, maintain neural environments, respond to injuries, and regulate neuroinflammation. Despite their significant impact on various physiological and pathological processes across mammalian biology, there remains a notable gap in our understanding of how microglia perceive and transmit mechanical signals in both normal and diseased states. Recent studies have revealed that microglia possess the ability to detect changes in the mechanical properties of their environment, such as alterations in stiffness or pressure. These changes may occur during development, aging, or in pathological conditions such as trauma or neurodegenerative diseases. This review will discuss microglial Piezo1 mechanosensitive channels as potential therapeutic targets for Alzheimer\u27s disease (AD). The structure, function, and modulation of Piezo1 will be discussed, as well as its role in facilitating microglial clearance of misfolded amyloid-β (Aβ) proteins implicated in the pathology of AD