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THE ROLE OF CORE-BINDING FACTOR SUBUNIT BETA (CBFβ) AND THE RUNT-RELATED TRANSCRIPTION FACTOR (RUNX) FAMILY IN MALE GERMLINE DEVELOPMENT
Full text linkThe precise regulation of spermatogenesis, involving a tightly controlled balance between spermatogonial proliferation and differentiation, is essential to support continuous sperm production and male fertility. Disruptions to this balance can impair germ cell maturation and compromise fertility. Using conditional knockout mouse models, our study revealed the previously unexplored critical role of the Core-Binding Factor Subunit Beta (CBFβ) as a transcriptional cofactor in maintaining male fertility through the regulation of germ cell proliferation and differentiation during prepubertal development. Our study also unravels the functional role of CBFβ in maintaining a delicate balance between proliferation and differentiation that is established early in development and necessary to complete terminal differentiation from the undifferentiated spermatogonia population. Furthermore, using spatial transcriptomic, we identified critical cell cycle regulatory genes as targets of CBFβ in the germline, suggesting its involvement in the overall cell cycle control during spermatogonial proliferation and meiotic progression. To further investigate the intricate balance that CBFβ has to maintain between proliferation and differentiation, we examined the functional partners of CBFβ. CBFβ is an established cofactor for the Runt-related Transcription Factor (RUNX) family in many developmental processes. Investigations into the interaction of CBFβ with the RUNX proteins identified RUNX1 and RUNX3 as binding partners of CBFβ in the male germline. Protein expression profiling also revealed distinct expression patterns of RUNX1 and RUNX3, particularly regarding their temporal dynamics during specific cell cycle phases in the undifferentiated spermatogonia. Notably, RUNX1 expression is elevated in proliferative germ cells, reaching its peak during the late stages of the cell cycle (G2/M phases). Using CUT&RUN, we identified shared targets among CBFβ, RUNX1, and RUNX3 through Runt motif binding domain. In addition, we detected enrichments of other motifs belonging to transcription factors involved in proliferation and differentiation in targets shared among CBFβ, RUNX1, and RUNX3. Moreover, we uncovered distinct yet complementary targets involved in proliferation and differentiation processes by CBFβ-RUNX1and CBFβ-RUNX3, respectively. Interestingly, we also identified RUNX-independent targets of CBFβ, indicating a broader cell cycle regulatory role of CBFβ involving other unidentified partners. Here, our study suggests that CBFβ, RUNX1, and RUNX3 create an interconnected network of transcriptional regulation in the undifferentiated spermatogonia to balance proliferation and differentiation. Together, this study advances our understanding of the molecular mechanisms underlying postnatal male germline regulation by emphasizing the functional role of CBFβ and its interactions with RUNX and other co-regulatory proteins. Collectively, this study further illuminates the complex regulatory networks in the prepubertal germline development essential to support lifelong spermatogenesis and male fertility
ELUCIDATING THE ROLE OF TRIACYLGLYCEROL LIPASE SUGAR-DEPENDENT PROTEIN 1 (SDP1) ON REDUCED SEED OIL ACCUMULATION AND MEDIUM CHAIN FATTY ACIDS LEVELS IN TRANSGENIC CAMELINA SATIVA
Full text linkThe global demand for sustainable aviation fuels (SAFs) is rising, but current feedstocks are limited. Medium-chain fatty acids (MCFAs; C8–C14) are attractive for SAF production because of their favorable combustion properties, yet natural sources such as coconut, palm kernel, and Cuphea species suffer from poor agronomic traits or restricted cultivation regions. Temperate oilseeds like Camelina sativa have therefore emerged as promising bioengineering platforms for MCFA production. However, previous efforts to express heterologous thioesterases and acyltransferases in Camelina introduced MCFAs at the expense of total oil yield, suggesting bottlenecks involving substrate specificity, precursor supply, and triacylglycerol (TAG) turnover by lipases such as SUGAR-DEPENDENT1 (SDP1).This study tested whether TAG turnover by SDP1 constrains MCFA accumulation. Two engineered Camelina lines were analyzed: the C10 line expressing CvFatB1, CnLPAAT, and CpuDGAT1, and the C12 line expressing UcFatB and CnLPAAT. Seed-specific suppression of CsSDP1 by RNAi increased oil yield across wild-type and engineered lines without impairing germination. In the C10 background, SDP1 suppression stabilized 10:0 retention and partially restored oil yield, indicating that SDP1 hydrolyzes 10:0-rich TAGs. In contrast, suppression in the C12 background reduced 12:0 levels while increasing polyunsaturated fatty acids, revealing a role for SDP1 in TAG remodeling needed for efficient laurate incorporation at sn-1/3 positions. Positional analysis confirmed that SDP1 acts selectively on unusual FA- and PUFA-containing TAGs.
Overall, SDP1 suppression improved seed size and oil yield but had divergent effects on MCFA composition. These results highlight the dual degradative and remodeling roles of TAG lipases and the need for coordinated engineering of lipases and acyltransferases to optimize MCFA accumulation in Camelina for SAF production
THICK-FILAMENT REGULATORY INTERACTIONS IN THE CARDIAC SARCOMERE
Full text linkCardiovascular disease remains the leading cause of mortality in the United States, contributing to 1 in 5 of all deaths. Hypertrophic cardiomyopathy (HCM) is a common heritable heart disease that can lead to decreased cardiac output, arrhythmias, and sudden death. Despite its frequency, patients with HCM have limited therapeutic options. While the causes of cardiovascular disease are multi-factorial, contractile deficits at the molecular level play a major role in cardiac dysfunction and may lead to pathological remodeling of the heart. The heart is comprised of several contractile proteins that work together to facilitate contraction, powering blood flow throughout the body. One of the defining properties of cardiac muscle is the Frank-Starling mechanism, which ensures that the volume of blood ejected from the heart during systole matches the volume that enters during diastole, thereby maintaining contractility on a beat-to-beat basis. At the cellular level, length-dependent activation (LDA) underlies the Frank-Starling mechanism. LDA is described by increased force and Ca2+-sensitivity as sarcomere length increases. While the molecular underpinnings of LDA are not fully understood, LDA and therefore the Frank-Starling mechanism are notably diminished during cardiac disease. Thus, understanding how contractile proteins contribute to LDA, and therefore overall cardiac function, is an essential step in developing effective therapeutics to benefit patient care.Cardiac myosin binding protein-C (cMyBP-C) is a commonly mutated protein in HCM clinical cases. Regulatory light chain (RLC) is a regulatory protein located in the myosin neck region. Both cMyBP-C and RLC undergo post-translational phosphorylation to alter protein function. Thick-filament proteins, such as cMyBP-C and RLC, and their interactions remain understudied and poorly understood. This dissertation assesses both: i) individual contributions from the thick-filament proteins cMyBP-C and RLC, and ii) interactions between the thick-filament proteins cMyBP-C and RLC on cardiac remodeling and cardiac muscle contraction. cMyBP-C knockout mouse models demonstrate that the loss of cMyBP-C promotes cellular signaling which initiates morphological remodeling of the myocardium as disease consistent with HCM progresses. Phosphorylation of RLC alters myosin head conformation and nucleotide handling rates, thereby increasing force and calcium sensitivity in a length-dependent manner. When assessing the combined contributions of the proteins, RLC phosphorylation amplified the effect of Ca2+-sensitivity in the cMyBP-C knockout mouse model. These findings suggest that cMyBP-C and RLC interact in a length- and phosphorylation-dependent manner and that this interaction may be essential for contractility in the healthy heart. Together, these studies provide an innovative look at thick-filament regulatory contributions to the cardiac sarcomere, advancing the knowledge in the field and providing groundwork for future therapeutic development
Examining the Relation of Socioeconomic Status with Child Behaviors and Parent Characteristics: The Role of Family Structure as a Protective Factor
Full text linkUnderstanding how socioeconomic status (SES) relates to child behaviors and parenting characteristics is critical for informing prevention and intervention efforts. Although SES has been widely studied in relation to child outcomes, less is known about whether family structure functions as a protective factor within low-income families The current study used an archival dataset of 130 preschoolers (ages 3 to 6 years of age) and their female caregivers (60 Head Start; 70 non-Head Start) to examine associations between multiple indicators of SES (Hollingshead Four Factor Index, annual family income, and Head Start status), children’s externalizing and internalizing behaviors, and parent characteristics (negative parenting, positive parenting, maternal parenting stress, maternal distress, and chaos in the home). Family structure (father figure present vs. absent in the household) was examined as a predictor and potential moderator. Consistent with expectations, lower SES was associated with less optimal parenting patterns. Specifically, lower Hollingshead Four Factor Index scores and lower income were significantly related to greater negative parenting and higher maternal parenting stress, and the Hollingshead Four Factor Index was positively associated with positive parenting. Eligibility for Head Start was also associated with higher negative and lower positive parenting. SES indicators were not significantly associated with child externalizing or internalizing behaviors, maternal distress, or chaos in the home. Family structure showed a modest association with parenting: female caregivers in father figure-present households reported lower negative parenting, and a trend emerged suggesting lower maternal distress in father figure-present homes. However, family structure did not moderate relations between SES and any child or parent outcomes. Overall, findings suggest that socioeconomic disadvantage was primarily linked to parenting processes rather than direct child behavior outcomes in this preschool sample and that father figure presence offered limited direct benefits and did not buffer SES effects. This study highlights the importance of examining multiple SES indicators and family context when assessing early risk and resilience processes in preschool-aged children
HONEY-BASED ARTIFICIAL SYNAPTIC DEVICES FOR RENEWABLE NEUROMORPHIC COMPUTING APPLICATIONS
Full text linkThe search for sustainable yet energy-efficient electronic devices has been a driving force in the development of artificial synaptic devices for neuromorphic computing. Neuromorphic computing offers an overlap of memory and processing driven by synaptic plasticity mechanisms found in the brain, potentially reducing overall power consumption for computing processes. In addition, sustainable components and natural organic components can be incorporated into artificial synaptic devices, allowing for an even more environmentally conscientious approach to the fabrication of such hardware. This thesis examines Honey and Honey-CNT of different processing conditions as natural organic materials in memristors for both their ReRAM and synaptic plasticity memory capabilities. The resistive switching capabilities, including switching characteristics and retention, were examined on Honey and Honey-CNT memristors. Synaptic plasticity was also examined for both honey and honey-CNT memristors, including short term and long term memory, spike-time-dependent plasticity, paired pulse facilitation, and potentiation and depression. These results show honey and honey-CNT's advancement as artificial synaptic device dielectrics and their capability to mimic the natural behaviors of biological synapses
Analysis of Thermally Modified Wood Strands and Thin Strand Veneers for Low-Value Balsam Fir
Full text linkBalsam fir is a species of wood located in the north-eastern regions of the US and around the Great lakesthat are typically small-diameter (less than 9-in), due to competition in the Great Lakes forests.
Therefore, it acts as fuel for forest fires and is systematically logged to improve forest health by the
United States Forest Service (USFS). Due to this, the USFS would like to determine whether there is a
market for balsam-fir along the value chain for structural applications in strand-based composites.
Thermal modification (TM) of balsam fir strands could improve its moisture and rot resistance which are
key concerns when producing mass timber composites. The feedstock for mass timber products and for
thin strand veneers are examined to determine the suitability of balsam fir strands.
In the first part of the study, balsam fir wood strands were thermally treated in a closed inert
environment with nitrogen gas at temperatures of 135°C, 150°C, and 165°C, with constant pressure of
1.4 MPa, and constant dwell time of 180 minutes. It was found that a higher intensity of thermal
modification on the wood strands improved on the extraction of hemicellulose within the wood fibers,
resulting in a 51.7% reduction in equilibrium moisture content (EMC).
In the second part of the study, balsam fir strands were used to manufacture thin wood strand
composites, which were then evaluated for their mechanical and physical characteristics. It was found
that a higher intensity of thermal modification on the wood strands improved on the dimensional
stability of the composites, resulting in a 71.8% reduction in thickness swell from the control strand
composites. Prediction equations for cross-laminated strand veneer lumber (CLSVL) from laminated
beam theory were used to predict the apparent stiffness of the mass timber composites that could be
developed from the already manufactured feedstock.
In the last part of the study, vacuum assisted thermal modification of balsam fir strands were examined
along various temperature, pressure and dwell time parameters to determine the mechanical and
physical properties of the wood strands under such conditions. Response surfaces were developed to
reproduce the results given any change in parameter. Much like in the first part of the study, it was found
that a higher intensity of thermal modification resulted in a 52.2% reduction in equilibrium moisture
content (EMC)
THE IMPACTS OF IT IDENTITY THREAT ON HOSPITALITY EMPLOYEES’ TURNOVER INTENTIONS AND ORGANIZATIONAL COMMITMENT
Full text linkThis dissertation includes two manuscripts. The first manuscript discusses information technology (IT) identity threat’s impacts on hotel employees’ turnover intention in the U.S. and China. Taking a cross-cultural perspective, this study examines the attitudes of U.S. and Chinese hotel employees toward IT identity threat and its impact on their turnover intentions amid the increasing use of robotics in the global hospitality industry. U.S. and Chinese hotel workers (N=194 and N=204, respectively) participated in the study. They were recruited through online research platforms: Credamo for the China sample and Prolific for the U.S. sample. Various analyses were conducted, including PLS-SEM, PLS-multigroup analysis, and t-tests. The results show that both Chinese and U.S. workers experience IT identity threat, which contributes to job insecurity and stress, thereby increasing turnover intention. Moreover, U.S. employees are more likely to resign from their current positions due to IT identity threats and stress than their Chinese counterparts. This study provides global insights into the intersection of information technology and human resource management in the hospitality industry. The findings highlight a shared concern among hospitality employees regarding the changes introduced by robots. Therefore, hospitality organizations should adopt effective strategies to minimize the negative impacts of robotics, foster a supportive organizational culture, and promote positive interactions between employees and robots. To the best of the authors’ knowledge, this study is the first to compare reactions of hospitality workers in two culturally distinct countries to IT identity threat. The study contributes to the theoretical understanding of IT identity threats and offers practical implications for hospitality managers.The second manuscript focuses on the IT identity threat impacts on employees’ organizational commitment in the hospitality industry. This research investigates hotel employees’ perceptions of IT identity threat and explores how such perceptions influence their affective organizational commitment in the context of growing robotic adoption within the hospitality industry. Data were collected from 450 hotel employees in China using the Credamo online survey platform. The analysis employed partial least squares structural equation modeling (PLS-SEM), PLS path modeling, and conditional process modeling to test the proposed relationships and moderating effects. The results indicate that hotel employees experience IT identity threat, which negatively affects their perceived organizational support and workplace well-being, ultimately reducing their affective organizational commitment. Furthermore, the moderating analysis reveals that employees working in low power distance environments exhibit more substantial declines in their sense of belonging when confronted with IT identity threats than those in high power distance settings. This study deepens understanding of the intersection between technological advancement and human resource management in the hospitality sector. The findings suggest that hotel organizations should implement targeted strategies to mitigate employees’ perceptions of identity threat, cultivate a supportive organizational climate, and encourage constructive collaboration between human workers and robotic systems. To the best of the authors’ knowledge, this study represents the first empirical comparison of hospitality employees’ responses to IT identity threat from a cultural perspective. It advances theoretical understanding of IT identity threat and provides actionable guidance for hospitality managers navigating the challenges of service automation
Carl Phillip Emmanuel Bach: A Unique Man in the Middle
Full text linkHow does one judge the significance of a composer? How does one determine how much of an impact a singular composer has? How influential were they on the music of the time and beyond? Why study thus? In the case of Carl Phillip Emmanuel Bach, his music exhibits characteristics of both periods as one evolved into another. His publication of a keyboard instruction manual offered timely musical insight for that time and beyond. But just how significant a role did he play in the transition? This paper will examine C.P.E. Bach’s music and his influence in deciding how important a role he played and how other composers viewed him. Qualitative musical analysis of some of his keyboard literature will be undertaken. There will be an investigation into the baroque and classical periods, their respective musical traits, and cultural insights. Thus, an analysis will be made between C.P.E. keyboard analysis and the musical characteristics of the periods. A conclusion can be determined that C.P.E. Bach was a significant, singular composer worth studying. C.P.E. Bach was ‘a unique man in the middle’ through his musical innovation, ingenuity, and inventio
The potential scale-up of sustainable aviation fuels production capacity to meet global and EU policy targets
No full textSustainable aviation fuels (SAF) can reduce aviation greenhouse gas emissions, yet their production scale-up to meet policy goals remains unexplored. Here, we describe the Global SAF Capacity Database to quantify global and European Union (EU) SAF capacity, comparing it to production capacity announcements. Despite announcements of 9.1 Mt year(2.2 Mt yearin the EU) by 2024 and 38.9 Mt year(9.3 Mt yearin the EU) by 2030, only 24% (26% in the EU) of the announced capacity was realized on time by 2024. Over 40% of the announced capacity for 2030 risks delays or cancellations. Using a diffusion model parametrized by announced capacity, realization rates, expected demand, and historical growth analogs, we calculate SAF potential scale-up to meet net-zero carbon emissions by 2050. Even if SAF follows the rapid scale-up of solar and wind energy, the global and EU capacity will fall short of respective targets by 42% and 18% in 2030, and 7% and 5% in 2050
Application of artificial intelligence in educational measurement: opportunities and ethical challenges
Full text link人工智能（Artificial Intelligence, AI）与教育测量的结合促进了测评方法的转变，通过机器学习和自然语言处理，实现了自动评分、快速内容分析和个性化反馈。这些发展为学生的表现提供了宝贵的见解，同时也提升了整体测评体验。然而，AI在教育领域的应用也引发了有关效度、信度、透明性、公平性和公正性的重大伦理问题。算法偏差和AI决策过程不透明等问题有可能加剧不平等，影响测评结果。为此，包括教育工作者、政策制定者和测试机构在内的各利益相关方制定了指导方针，以确保AI在教育领域中的应用符合伦理规范。美国国家教育测量委员会测量与教育中的人工智能特别兴趣小组（AI in Measurement and Education, AIME）致力于制定该领域的伦理规范并推动研究的进一步发展。在本文中，不同背景的AIME成员共同探讨了AI工具在教育测量中的伦理影响，分析了自动化偏差和环境影响等重大挑战，并提出了确保AI在教育领域负责任且高效应用的解决方案