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The Impact of Economic Sanctions and War-Related Uncertainty on Oil Market Volatility: Evidence from the Russia-Ukraine War
No full textEconomic sanctions engender the disturbance of financial transactions between the sanctioner and the targeted nations. The Russia-Ukraine war also restricted Russia\u27s entry into financial and commodity markets, with reverberating effects on the global market. Hence, the study aims to elucidate the relationship between armed conflicts and economic sanctions enforced by the G7 nations, the crude oil market, and its corresponding volatility index, OVX. It seems that heightened levels of ambiguity, conflict, nervousness, and hostility have contributed to an increase in the fluctuation of the energy market, leading to an extreme response to economic sanctions. Our findings reveal that financial restrictions imposed by Australia, Japan, the UK, and the USA have led to higher uncertainty and increased volatility in the oil market. The news variable War exhibits higher volatility compared to Crude oil and Recession in the media press. The war-induced uncertainty has shown a significant impact on the oil volatility
The Impact of Audit Quality on Earnings Management in Publicly Listed U.S. Companies
No full textThis study examined the effect of Audit quality on Earnings management of publicly listed US companies. The dependent variable; Earnings management, was measured using discretionary accruals, while the Independent Variable; Audit quality, was proxied by factors Auditor size (Big Four), audit fees, and auditor tenure. The study adopted a quantitative research design to investigate the relationship between audit quality and earnings management. A sample of publicly listed U.S. companies was selected from the SandP 500 index, spanning a period of five years (e.g., 2018-2022). Financial data were sourced from publicly available databases such as SEC filings, annual reports, and audit reports. The study adopted themodel used by Tyokoso and Tsegba (2015). The findings of the study revealed that Audit Tenure had a positive but statistically insignificant effect on earnings management, Audit Firm Size had a negative and statistically significant effect on earnings management, Leverage exhibited a positive but statistically insignificant effect on earnings management, Cash Flow showed a negative and statistically significant effect on earnings management, and Firm Size had a negative and statistically significant effect on earnings management, meaning that larger firms engage in less earnings manipulation compared to smaller firms. Based on the findings, it was recommended that companies should engage larger, reputable audit firms (Big 4 auditors) to ensure higher financial reporting quality and reduced earnings manipulation
Strategy as What a Business Should Do Over Time to Succeed: A Case Study of Tesla, Inc
Get PDFWhy businesses succeed or fail is a central question in strategy. Extant literature is well developed in explaining the relative success of firms at a point in time. There is not as much known, however, about what a business should do over time to succeed. We begin to address this gap with a study of Tesla, Inc. Following recommendations to ensure reliability and validity (Gibbert et al., 2008), we study how Tesla succeeded as a startup in the capital and scale intensive industry, when the relevant technology and supporting infrastructure were nonexistent. We contrast Tesla with its competitors to draw conclusions. We then articulate strategy insights from the study including for a preliminary theory of strategy as what a business should do over time to succeed
Real-Time Dual-Arm Teleoperation Via Similarity-Transform Mapping
No full textRobotic teleoperation often relies on mode switching, scripted waypoints, or offline learning pipelines that constrain responsiveness and raise the barrier to deployment. This dissertation presents a markerless, similarity-transform gesture-mapping framework that enables a single operator to drive two UR3e collaborative arms in real time using natural bimanual hand motions captured by a Leap Motion sensor. A one-shot Umeyama calibration computes a uniform-scale rigid transform between the 60 Hz Leap frame and each robot base, after which millimeter-scale palm displacements are permuted, sign-corrected, and scaled (k≈1.5×10−3 m/mm) into meter-scale tool-center-point waypoints. The mapping, plus a five-sample moving-average filter, adds only 20 ms of processing latency; combined with a 10 Hz Real-Time Data Exchange stream and UR servo interpolation, the sensor-to-actuator delay averages 178 ms, well inside the 200 ms transparency threshold for human agency. Bench-top trials on a Windows 11 workstation demonstrate a mean positional error of 8 mm across a 0.3 m workspace, 21 ms internal pipeline latency, sub-30 ms inter-arm skew, and 0.41 s grasp-gesture latency with ±0.3 mm gripper repeatability. A layered safety architecture couples gesture-based halts, occlusion freezes, and workspace clamps with the cobot’s native force limits, yielding immediate, intuitive braking without external sensors. Compared with state-of-the-art single-arm or mode-switching systems, the proposed method offers faster setup, lower cognitive load, and dual-arm synchronicity using only commodity hardware. The work establishes a reproducible software stack for rapid evaluation of gesture-controlled manipulators and outlines future extensions in six-DOF orientation, multi-sensor frustum stitching, and vibrotactile feedback
Exploring Flourishing and Holistic Well-Being in Individuals With Lower-Limb Amputation
No full textThis thesis seeks to advance understanding of flourishing among individuals with lower limb amputations. Flourishing is defined as a state of sustainable well-being that can be assessed across six key domains of an individual’s life. These domains include happiness and life satisfaction, mental and physical health, meaning and purpose, character and virtue, close social relationships, and financial and material stability. Individuals living with amputation were recruited from a local clinic and completed a demographic survey along with the VanderWeele flourishing scale. After expressing interest through the screening survey, participants (n = 12) were invited to participate in one of three focus groups. The average scale score was 95 out of a possible 120, which demonstrates strong flourishing among participants. Emerging themes reflect the physical, psychological, and social factors that either hindered or supported flourishing after experiencing lower limb amputation. Resulting themes emphasize the importance of peer-support groups, spirituality, mindset, and engaging in a range of activities (such as sports, support groups, or volunteering) for flourishing. Findings can inform actionable insights for interventions, policies, and support systems that promote holistic well-being and equitable care
Structural Vibration Analysis of The Multi Mission Radioisotope Thermoelectric Generator (MMRTG) on the Martian Surface
No full textA Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) is a radioisotope power system designed for use within both planetary atmospheres and the vacuum of space. A radioisotope power system uses a radioisotope fuel source which generates heat that is then converted into electricity by the system’s thermocouples. These generators are used as a power source on space missions with very long service durations. MMRTGs have a required usage lifespan of roughly fourteen years, therefore the system must withstand stressors without suffering significant structural damage that would affect their functionality.
It is important to take into consideration that MMRTGs house radioactive materials; therefore, their resilience is crucial not only to the success of the space mission but also to the safety of the public. In order to minimize the dangers posed by these nuclear materials it is necessary to optimize the structural integrity of the MMRTG. Thus, ensuring that in the event of a mission failure wherein the MMRTG is sent into Earth’s atmosphere, the nuclear material housed within the generator remains contained. For these reasons, it is necessary to ensure the structural integrity and resilience of the MMRTG and to provide recommendations for material optimizations that can be applied to its construction. In service of this goal, this paper presents a finite element analysis (FEA) of an MMRTG model subjected to various impact scenarios. An analysis of the MMRTG’s structural integrity under gravitational loads will be performed along with a direct drop impact test and a vibrational analysis with the purpose of simulating those shocks that the MMRTG would experience while traversing Martian terrain via Mars rover. Using COMSOL Multiphysics, a comprehensive 3D model was developed, incorporating boundary conditions and material properties appropriate for simulating impact environments. Data on PSD estimation for terrain simulation, construction dimensions, and material properties was gathered via publicly available documents from various sources including the United States Department of Defense (DoD) and The National Aeronautics and Space Administration (NASA). By utilizing this information this study aims to understand the structural integrity and resilience of MMRTGs under relevant conditions, with a focus on time-dependent shock load application and structural response
Optimizing Growth Conditions of Chlorella Algae for Enhanced Biomass and Oxygen Production
No full textIncreasing Earth\u27s carbon dioxide (CO₂) levels contribute immensely to global warming. At the same time, future Mars colonization requires innovative systems for oxygen production. This study explores how Chlorella algae can help control environmental challenges on Earth, support life on Mars, and produce biomass as an alternative to renewable energy. Chlorella is known for its high photosynthetic efficiency in capturing CO2 for growth, producing O2 and biomass used for biofuel production. It was studied under varying CO₂ concentrations and pressure conditions. Each experiment was performed using a photobioreactor setup and optimized algae growth conditions. These were assessed to understand its ability to grow and produce O2 and biomass used for biofuel production and sustainable energy to address environmental problems. The bioreactor system and the CO2 meter oxygen sensor were key in maximizing Chlorella growth for scalable uses on Earth. The results highlight how vital Chlorella is for lowering CO2 emissions, producing clean energy, and sustaining life on Mars via O2 produced. The experimental results showed that higher CO₂ concentration enhanced Chlorella growth and O2 production, while low- pressure conditions, mimicking Martian environments, supported stable photosynthesis. Under gas mixture atmospheric (428.15 ppm) CO₂ at 1atm pressure conditions in experiment 1, Chlorella showed stable growth with a modest O₂ increase of 0.68%. O2 production greatly improved under high (334000 ppm) CO₂ concentration experiment 2, reaching an increase change of light on and off 4.52%. Further growth under low vacuum pressures of experiments 3 and 4 confirmed that Chlorella can sustain photosynthesis in Martian-like environments. However, the most surprising growth and O2 production occurred in experiment 6, where a mix of 0.13 atm absolute vacuum pressure and high (334000 ppm) CO₂ concentration led to a peak O₂ concentration of 72.01% and selected as the best optimized conditions growth. The combined six experiments dry Chlorella was extracted using Soxhlet extraction to assess its biofuel potential, and 0.14 g of oil was successfully extracted, validating its application as a good prospect for carbon capture, renewable biofuel production, and extraterrestrial life support systems that address environmental sustainability on Earth and enable self-sufficient habitats beyond our planet
The Relationship Between Women\u27s Use of Birth Control Pills and Their Perceptions of the Mental Health Effects (Depression and Anxiety) of the Pill
Get PDFThe National Library of Medicine published an article mentioning how hormonal contraception might cause and sustain depression in some patients (Mu & Kulkarni, 2022). Currently, approximately 25% of women ages 15-44 who are currently using a form of contraception rely on the pill as the primary method (Cooper, 2024). However, there is still no definite yes or no answer in terms of whether the use of birth control pills can lead to mental health effects. The objective of this paper is to see what the current perceptions on whether birth control pills have an effect on mental health based on women\u27s past use of it. A survey with prompts stating that the use of birth control leads to mental health effects was used to look at the level of perception. For the prompts with negative connotations regarding the use of the pill, the level of disagreement between the no previous and would not consider pill use and the previous and current pill users, as well as the previous, but no longer pill users, were of statistical significance. On the contrary, for all of these statements, the no previous and would consider pill use responses showed no statistical difference when compared to the no previous and would not consider pill use participants. A clear pattern was seen between the past usage of the pill and experiences with it and the level of disagreement on whether it has negative or positive effects on mental health. This goes to show the impact of perception when it comes to health behaviors
Effect of Antibiotics in Preventing Borrelia burgdorferi Biofilm Formation
No full textLyme disease, caused by the bacterium Borrelia burgdorferi, is the most prevalent tick-borne illness in the United States, with approximately 500,000 annual diagnoses. Despite antibiotic treatment, B. burgdorferi can persist in the host, often leading to relapses. Its treatment is further complicated by this pathogen’s ability to form biofilms, a morphological form that enhances antibiotic resistance and serves as a defense mechanism. Previous studies have shown that established biofilms are highly resistant to eradication, even at high antibiotic concentrations. While recent therapeutic strategies advocate administering antibiotics after a tick bite to prevent B. burgdorferi biofilm formation, supporting research data remain lacking.
This study aimed to evaluate the efficacy of various antibiotics (doxycycline, dapsone, azithromycin, and hygromycin A) in inhibiting biofilm formation in vitro using crystal violet biofilm assays, LIVE/DEAD staining, and subculture assays.
The results showed that doxycycline, the most commonly prescribed antibiotic for Lyme disease, and azithromycin, widely used in Europe, demonstrated limited efficacy both against established biofilms and in preventing biofilm formation. Hygromycin A, a B. burgdorferi-specific antibiotic, showed moderate efficacy as a monotherapy but achieved significant results in dual therapy, particularly when combined with dapsone. The combination of hygromycin A and dapsone reduced biofilm mass by nearly 50% and prevented biofilm recovery in subculture assays.
These findings suggest that antibiotics used for Lyme disease treatment may be inadequate for addressing B. burgdorferi biofilm formation. This research underscores the importance of early, targeted interventions and highlights the potential of non-standard antibiotics and combination therapies as innovative strategies to combat B. burgdorferi biofilm formation. This study adds to the expanding body of research on Lyme disease treatment, highlighting the urgent need for innovative strategies to address the challenges presented by the bacteria’s adaptive defense mechanisms
Finding Courage in Psychologically Unsafe Environments: The Impact of Trait Social Courage and Voice on Leadership Emergence
No full textThis paper explores the role trait social courage has in psychologically unsafe team environments, specifically examining its impact on voice and leadership emergence. Using a sample of undergraduate students engaged in a semester long team business simulation, surveyed at multiple time points and with multiple raters, we found support that trait social courage is activated under conditions of low psychological safety, resulting in voice behaviors. Further, voice was related to perceptions of leadership emergence. Implications and directions for future research are discussed