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Effect of a Social Determinants of Health Video Case Study on Attitudes Toward Poverty and Empathy in Nursing Students: A Quasi-experimental Study
No full textThere is a need to integrate social determinants of health (SDOH) education throughout the undergraduate nursing curriculum. However, it is most often emphasized in community and public health courses of junior and senior-level nursing students. As a SDOH, poverty is a significant barrier to achieving optimal health and wellness. Nurse educators must be equipped with accessible and effective SDOH teaching strategies that can be implemented earlier in the nursing curriculum. These strategies can be used to help undergraduate nursing students begin to recognize their attitudes and empathy toward individuals living in poverty.
The main purpose of this study was to examine the effect of a SDOH classroom activity on attitudes toward poverty in prelicensure nursing students. The second purpose was to examine the effects of a SDOH classroom activity on empathy in prelicensure nursing students. The differences in empathy and attitudes toward poverty before and after participating in the activity were also explored. The final purpose was to examine the difference in the effect of a SDOH classroom activity on empathy and gender identity in prelicensure nursing students.
A quasi-experimental, multi-site, two-group, pretest-posttest design was conducted with a nonequivalent comparison group. A convenience sample of 98 prelicensure nursing students from three undergraduate nursing programs located in the Midwest and Northeastern parts of the U.S. participated in a SDOH classroom activity and completed pretest and posttest surveys. The study intervention consisted of a SDOH video versus paper case study followed by faculty-led, structured debriefing. The intervention group watched the video case study, while the comparison group read a paper case study. The Attitude Toward Poverty-Short Form (ATP-SF) and Jefferson Scale of Empathy for Health Professions Students (JSE-HPS) were administered to participants before and after the SDOH classroom activity.
A statistically significant difference was found between total pretest and posttest ATP-SF scores. No statistically significant effect on posttest ATP-SF scores based on the type of case study was found. A statistically significant effect on JSE-HPS scores based on case study type was identified; however, the size of this effect was small. No statistically significant differences were found in the effect of the type of case study on empathy and attitudes toward poverty. Unequal sample sizes between gender identities of participants prevented a valid analysis of the data.
The findings from this study provide support that a SDOH classroom activity may be an effective teaching strategy to improve attitudes toward poverty in prelicensure nursing students. Although the type of case study was not effective, both groups received identical faculty-led debriefing and attitudes toward poverty were improved for both groups. Future research is needed to explore the effect of debriefing on attitudes toward poverty. Additionally, experiential SDOH teaching strategies should be employed in researching empathy as an acquired skill in prelicensure nursing students
LO-Path Modulated Receivers for Cognitive Radio and Phased Array Systems
No full textIncreasing demand for wireless connectivity at faster speeds and more devices is stressing thecurrent infrastructure as technologies such as autonomous driving, unmanned aerial vehicles, and satellite communications become more commercially available. There is a massive need for efficient use of already existing spectrum. Two methods to improve efficiency are implementing cognitive radio (CR) networks that autonomously take advantage of all available bands and resources, and phased array systems that allow for spatial diversity and the reuse of spectrum.
One design strategy in both methods is to use modulated local oscillator (LO) waveforms to drive the mixers in the receiver to provide either sensing capabilities, or beamforming of the phased array. Cognitive radio networks are an agile and robust solution to increasing RF congestion, as they are capable of being aware of the electromagnetic (EM) environment around them, adjust their operating parameters to maintain the maximum link performance, and learn their surrounding en- vironment across various conditions. A key performance metric in CR networks is in the accuracy and speed of gathering information about the available spectrum around them. In this dissertation, we introduce a full end-to-end CR node that uses an EM environmentally aware (EMEA) sensor, based on CS-based spectrum sensing hardware, to provide rapid wide-band frequency information to a machine learning based decision engine back-end. This Intelligent Transceiver Radio Node (ITRN) is capable spectrum sensing 2,000x faster than conventional methods which aides in a cre- ating a rapid response to fast moving frequency jammers. In addition, this dissertation introduces the Directional Spectrum Sensor (DSS) architecture that combines the benefits of beamforming with rapid CS-based spectrum sensing hardware. This results in the detection sensitivity improv- ing as large blockers are spatially filtered out.
This dissertation will also introduce a theoretical procedure using a dual mode sensing hardware that is capable of rapidly scanning the spectral and spatial domain. This provides future CR applications and integrations with the full picture of their surrounding environment in both the spatial and spectral domains. To further leverage the modulated-LO approach, the time-modulated LO (TM-LO) vector modulator (VM) architecture is introduced for beamforming receiver applications. Beamforming receivers use the spatial domain to increase sensitivity, reject spatial interferers, and increase communication to multiple users simultaneously with multiple beams. Typically the phase shifts and amplitude control are achieved by using conventional vector modulators (VM) consisting of multiple gain slices. The number of slices grows as a product of the number of beams, antenna elements, and bits of resolution. Thus resulting in significant area and power consumption, placing limitations on implementation for large arrays and potentially for CR applications.
Instead, we use time-modulation techniques to break the area and VM-resolution tradeoff. The TM-LO uses rail-to-rail LO waveforms generated from digitally synthesized blocks and pass-gate switches to perform the down-conversion and amplitude/phase control of the received signal. A single element receiver achieves 0.2 dB RMS gain error and 1.4◦RMS phase error with 5 bits of amplitude/phase resolution across a 360◦range is implemented in a 65 nm CMOS process as a proof-of-concept prototype. Without time-modulation, the hardware is capable of 3-bits of resolution. The inherent digital nature of TM-LO architecture provides opportunity very compact front-ends suitable for large arrays and lower voltage technologies. Four TM-LO chips were used to create a beamform- ing receiver that is capable of harmonic beamforming. The phased array implementation based on the TM-LO is presented and discussed.
In summary, several architectures are presented in this dissertion that use modulated LO waveforms to perform rapid state-of-the-art sensing capability to be integrated into an end-to-end CR platform and a new block level approach using the time-domain to create compact VMs for phased array systems. The system-level integration highlights the massive advantage of hardware insights that can be added to existing systems with low power, area, and integration costs. These systems can interface with new paradigms of signal processing and machine learning for massive performance improvement. The block level insights derived from the system-level work present new opportunties for circuit approaches that are tailored to the specific system requirements
Community Insights on Weather-Induced Energy Insecurity: A Case Study of Extreme Heat and Power Outages in North Lawndale, Chicago
No full textExtreme heat and power outages are two growing climate-driven threats that endanger the health and safety of vulnerable households and communities. Heat waves are among the deadliest natural hazards in the United States, and they are becoming more frequent, longer lasting, and more intense. Power outages, also on the rise, compound the risks posed by heat waves. These threats not only intersect, they also disproportionately impact communities with high economic, health, and social vulnerability—many of which have been shaped by a legacy of structural discrimination. The US Environmental Protection Agency estimates that Black residents are 40% more likely to live in areas with higher mortality rates from rising temperatures than non-Black residents.
This report, part of the Energy Opportunity Lab at the Center on Global Energy Policy at Columbia University’s School of International and Public Affairs, explores how residents of North Lawndale, a predominantly Black and historically under-resourced neighborhood on Chicago’s West Side, experience the compounded effects of heat waves and power outages. With rates of chronic health issues, poverty, unemployment, and energy burden (the percentage of income used to pay energy bills) well above state averages, North Lawndale contends with more frequent and longer outages as well as greater barriers to coping with extreme heat compared to wealthier neighborhoods in Chicago
Africa’s Energy PPPs Succeed When Planning, Policy, and Public Interest Are Prioritized
No full textPublic-Private Partnerships (PPPs), which leverage private sector expertise and investment to reduce the fiscal burden on governments, have emerged as a key strategy to address financing bottlenecks for infrastructure projects. The performance of PPP projects across Africa has been mixed, with successes tempered by shortcomings in project preparation, procurement, risk management, and transparency. Without identifying and addressing these challenges, PPPs can incur high costs while producing limited benefits.
Drawing on a comparative analysis of three diverse projects—the Bujagali Hydroelectric Project in Uganda, the Tema LNG Import Terminal in Ghana, and the Kathu Solar Park in South Africa—this commentary explores how differences in project preparation, governance structures, and stakeholder alignment have influenced PPP project outcomes. Going beyond well-known shortcomings, it focuses on the enabling factors—such as institutional capacity, policy coordination, transparent procurement, and community engagement—for PPPs to deliver affordable and sustainable energy services while minimizing fiscal risks. By examining what distinguishes more successful projects from those that fall short, this commentary offers practical insights into how PPPs can be structured and supported to better serve the public interest, especially in fiscally constrained environments
The Exportation of American Gun Culture: A Survey of Korean University Students
No full textThe United States has a unique gun culture represented in and promulgated by its entertainment media. Fictional entertainment media can impact public opinion by shaping perceptions of reality or giving cues about normative behavior, and such media could be used to transmit tenets of American gun culture to overseas audiences. This study examines whether such exportation occurs by surveying South Korean university students and evaluating whether their media consumption habits impact their perceptions of guns. South Korea’s state of sociopolitical discontent could render its youth receptive to the specific portrayals of guns in American culture, which depicts them as tools for power, respect, and extralegal justice. Students’ selection of major and year in college both impact their level of agreement with gun culture, such that respondents are more pro-gun if they chose to major in English language and literature and if they’ve spent a longer time in college. However, these relationships are not necessarily causal and my main results are primarily inconclusive, as the agreement with American gun culture in both departments begins to converge across class years
Metallaphotoredox Catalysis from Red to Blue: New Methods in C–N and C–C Cross-Coupling
No full textDual transition metal and photoredox catalysis is a powerful tool that harnesses visible light to enable novel chemical transformations. The conferral of open-shell processes facilitated by photoredox catalysis to the modular bond-forming capabilities of transition metal cross-coupling has led to the development of many new synthetic methods that couple unactivated, bench-stable feedstock chemicals to form value-added products. The Rovis group has previously reported the use of deep red and near infrared light in photoredox catalysis.
Herein, we report the use of an osmium-based photosensitizer in combination with deep red light to realize a dual nickel-catalyzed C–N cross-coupling method with batch-scalability, greater functional group tolerance, and decreased deleterious side-reactivity. Additionally, we report the synthesis and characterization of a library of osmium-based photocatalysts to facilitate the adoption of low energy photoredox catalysis. Finally, we leverage the unique properties of copper and iridium-based photoredox catalysis with blue light to enable the cross-coupling of tertiary benzylic radicals to furnish all-carbon diaryl quaternary centers
Paddock Tree Arrangement and Pasture Photosynthetic Heat Tolerance in a Temperate Tree‐Pasture Grazing System Under Climate Change Scenarios
No full textClimate change and associated extreme heat events threaten productivity in agricultural systems. Integrating trees into grazing/pasture systems has the potential to enhance resilience to warming. However, the extent to which tree cover can buffer the impacts of climate change on pasture species is unclear. We examined how tree density and spatial configuration influence leaf nitrogen content, specific leaf area, and photosynthetic heat tolerance (Tcrit) of dominant pasture species in a temperate Australian landscape. Traits were assessed across fine-scale spatial gradients from individual trees under different structural configurations. Future thermal safety margins (TSMs) were projected under two climate emission scenarios—the best-case scenario (SSP1-2.6) and the worst-case scenario (SSP5-8.5) using 28 earth system models. While leaf nitrogen varied with tree spatial configuration, Tcrit and TSMs remained largely conserved. Projected warming substantially reduced TSMs without exceeding thermal thresholds, suggesting limited physiological capacity for heat tolerance adjustment. These results highlight the constrained role of tree cover in buffering climate impacts on pasture species and the need for broader adaptation strategies in agricultural systems.
Keywords: earth system models; leaf functional traits; leaf nitrogen; photosystem II critical temperature; thermal safety margi
Adaptation and Decarbonization in Osaka
No full textOsaka is one of the most vulnerable cities to climate change in Japan due to its flat topography and location in the hot south of the country. As a result, Osaka needs to drive a mixed climate action plan of mitigating climate change through promoting renewable energy and smoothing consumption, and adapting to the effects through building flood defenses and introducing extreme heat warning systems.
Keywords: Adaptation, low carbon transition, extreme heat, sea level ris
Development and optimization of a clinical harmonic motion imaging system for focused ultrasound ablation monitoring and assessment
No full textBreast cancer is the most commonly diagnosed invasive cancer in women both globally, in which breast cancer accounts for 25% of new cancer cases, and within the United States, with an estimated 31% of new cancer diagnoses [1, 2, 3]. Benign (non-cancerous) breast disease has a much larger prevalence; it is estimated that 80% of breast biopsies are benign [4, 5, 6].
Of all breast cancer cases, more than 90% are non-metastatic at the time of diagnosis [7]. In non-metastatic patients, the therapeutic goal is tumor eradication and recurrence prevention. The standard of care consists of systemic therapy, determined by molecular subtype, and local therapy, which consists of either total mastectomy or excision plus radiation [7]. Metastatic breast cancer is also treated systemically according to subtype, with goals of prolonging life and palliating symptoms. Local therapy is typically only used for palliative purposes in patients with metastatic disease [7]. In benign cases, surgical exicision may be performed primarily for symptom palliation [8, 9, 10, 4].
Minimally invasive and non-invasive techniques for tumor extirpation are being investigated as an alternative to surgical excision, for both benign and malignant neoplasms. Minimally invasive and non-invasive procedures are advantageous in economic benefits, reduced recovery time, absence of general anesthesia, and improved cosmetic result. Additionally, in conventional tumor surgical excisions, there is a lack of intraoperative imaging that would aid in achieving clear margins, resulting in high rates of reoperation to excise residual tumor [11, 12]. Incorporating intraoperative imaging techniques could enable higher rates of clear margins with breast conserving procedures. Such monitoring methods may be easier to achieve with minimally invasive and non-invasive techniques than with surgery.
Ultrasound elastography guides FUS ablation by monitoring changing mechanical properties of tissue that occur during thermal ablation. Harmonic Motion Imaging (HMI) is an elastography method, in which an oscillatory radiation force is used to generate tissue displacement at a specified frequency. As displacement is measured on the axis of the applied radiation force, HMI is advantageous for FUS monitoring at the site of the FUS transducer focus. Due to excitation of displacement at a specified frequency, HMI is advantageous in distinguishing displacement information from extraneous noise. HMI has previously been shown to distinguish stiffness related changes during FUS ablation [13, 14, 15, 16, 17, 18].In this dissertation, we aim to further improve our HMI guided FUS (HMIgFUS) system, and test its efficacy in pre-clinical studies and, for the first time, in in vivo clinical studies.
First, we explored two methods of optimizing the HMIgFUS system. In conventional HMIgFUS, imaging is performed concurrently with FUS application without interruption, such that FUS interference must be removed from radiofrequency (RF) data prior to displacement estimation. However, under high FUS pressure and long FUS treatment durations, previously used methods for FUS interference filtering, namely notch filtering, were ineffective. Thus, my first sub-aim was to investigate methods of FUS interference filtering, for the purpose of optimizing FUS ablation efficiency (high FUS power output) while minimizing FUS interference (for accurate displace- ment estimation). To achieve this goal, I performed HMIgFUS in an ex vivo canine liver, with a combination of FUS durations and peak positive pressures. I evaluated the performance of three methods of FUS interference filtering on these datasets: notch filtering, FUS-net, and interleaved HMIgFUS. We found that the interleaved method for HMIgFUS was found to be significantly robust in avoiding FUS interference in all tested cases for FUS ablation monitoring, especially cases with high FUS pressures and long durations, as opposed to traditional notch filtering and FUS-net filtering. FUS-net and notch filtering are advantageous in that they can be used with continuous FUS output, and thus may be more advantageous for low-intensity FUS purposes. FUS-net has also exhibited greater potential in FUS interference filtering while preserving frequency information, as compared with notch filtering.
In the second sub-aim, we investigated the use of multiple amplitude modulated (AM) frequency HMIgFUS for improved lesion size estimation. In previous studies, amplitude modulation was performed during HMIgFUS with a sinusoidal signal at a single frequency [19]. However, previous studies have shown benefits of multiple AM-frequency HMI imaging for improved contrast and CNR [20, 21, 22]. Multi-AM-frequency HMI was first performed in a tissue-mimicking phantom with embedded inclusions at three different sizes and stiffnesses, to evaluate the relationship of AM-frequency on inclusion size estimation. Multi-AM-frequency HMIgFUS ablation was then performed and evaluated in two ex vivo chicken muscle specimens. We found that low AM-frequency HMIgFUS may be ideal for lesion size estimation. In chicken muscle HMIgFUS, the lowest AM frequency was found to correlate the best with the final lesion size, as determined with gross pathology. However, contrast over time was highest and varied more over time with high AM frequencies, suggesting that high AM frequencies may be better suited for lesion progression monitoring.
In our second aim, preclinical studies of HMIgFUS in a breast cancer mouse model were performed in order to test our methods prior to clinical application, as well as to measure longitudinal responses to FUS ablation monotherapy. The breast cancer mouse model model was studied first longitudinally without treatment, acquiring HMI displacement images at the primary mammary tumor and at the liver. This study was performed to familiarize us with the mouse model and to assess HMI as a longitudinal monitoring imaging method in untreated mice. We found that HMI can distinguish differences in stiffness between the primary tumor and neighboring tissue, and the liver and its neighboring tissue. There also appears to be stiffening in both the primary tumor and liver with disease progression, which in the case of the liver, may be correlated to metastasis progression. Two preclinical HMIgFUS studies were then performed; one study in which mice developed two tumor sites, so that each mouse served as its own control; and one in which mice developed one tumor site each, so that longitudinal development of the single tumor following FUS ablation could be assessed. In both studies, acute and longitudinal effects of FUS ablation were assessed, and the monitoring and predictive ability of HMI during FUS was also assessed. We found a significant correlation between multi-AM HMIgFUS displacement percent change and 3D HMI displacement imaging percent change, suggesting that multi-AM HMIgFUS can reliably estimate the ablation lesion size during ablation. Our ablation results were further validated with bioluminescence imaging, which showed decreased luciferin expression in treated mice immediately following ablation. Finally, treated mice experienced a slower rate of tumor growth compared to untreated mice, suggesting the clinical utility of FUS ablation.
Finally, HMIgFUS was demonstrated for the first time in clinic, and the efficacy of HMIgFUS ablation and monitoring was assessed. In this first HMIgFUS clinical study, patients with non-metastatic early stage breast cancer or benign breast tumors that were scheduled by their clinical care team to receive surgical resection of the breast tumor were enrolled. We performed HMIgFUS under anesthesia in the operating room immediately prior to tumor resection. Among the ten patients out of 12 in which HMIgFUS monitoring was found to acquire and estimate reliable displacement data, we found a mean HMI displacement change of -53.3%±16.9, comparing the maximum displacement acquired during HMIgFUS with the displacement estimated at the final HMIgFUS timepoint. These initial results suggest that HMI displacement can measure FUS induced mechanical changes in tumor tissue, and that the measured displacement may differ among patients
Advancing the Understanding of Reproductive Coercion among Women in the United States
No full textIn the United States, over 8% of women have experienced reproductive coercion by a partner during their lifetime. Reproductive coercion involves deliberate behaviors that undermine reproductive decision-making and increase the risk of unintended pregnancy and sexually transmitted infections. These behaviors include pressuring a partner to become pregnant (pregnancy coercion), sabotaging birth control, such as removing or damaging a condom (condom manipulation), or forcing a partner to continue or end a pregnancy (controlling the outcome of a pregnancy). Despite its clinical relevance, addressing reproductive coercion has been hindered by conceptual ambiguity, lack of validated instruments, and limited research on the influence of community- and societal-level factors.
The purpose of this dissertation was to strengthen the evidence base on reproductive coercion to inform research, clinical practice, and policy. The aims of this dissertation were to: (1) synthesize and critically assess existing evidence on the prevalence and associated factors of reproductive coercion; (2) evaluate the validity and reliability of the Reproductive Coercion Scale; and (3) identify multilevel factors associated with reproductive coercion.
This dissertation comprised three studies: (1) a systematic review conducted in accordance with PRISMA guidelines to assess U.S.-based quantitative studies published through April 2024 on reproductive coercion prevalence and associated factors, with risk of bias evaluated using the Joanna Briggs Institute Critical Appraisal Tools; (2) a psychometric evaluation of the Reproductive Coercion Scale, including exploratory factor analysis, internal consistency assessment, and examination of convergent and discriminant validity; and (3) a cross-sectional analysis of baseline data from the American Women: Assessing Risk Epidemiologically cohort, geocoded and merged with publicly available datasets, to examine multilevel factors associated with reproductive coercion using bivariate and multivariable regression.
The systematic review synthesized findings from 23 studies that primarily examined demographic and behavioral factors associated with reproductive coercion. All studies were rated as having a moderate to high risk of bias due to their reliance on unvalidated measures of reproductive coercion, raising concerns about the trustworthiness of the evidence base. In the psychometric evaluation, exploratory factor analysis supported a two-factor solution of pregnancy coercion and condom manipulation, resulting in an 8-item Refined Reproductive Coercion Scale that demonstrated acceptable internal consistency, strong structural validity, and evidence of convergent and discriminant validity.
In the cross-sectional analysis, higher sexual self-efficacy, decision-making power, and communication ability were associated with reduced likelihood of reproductive coercion, whereas having a partner with a history of sexually transmitted infections was associated with increased likelihood. Greater perceived social support was associated with lower odds of reproductive coercion, while women affected by reproductive coercion were more likely to have engaged with women’s health specialists. No significant associations were observed for community- or societal-level factors.
This dissertation advances the study of reproductive coercion through validation of the 8-item Refined Reproductive Coercion Scale and the application of a multilevel approach to examine reproductive coercion across individual, interpersonal, community, and societal levels. Findings underscore the critical role of nurses in addressing reproductive coercion through clinical practice and advocacy. Future research should continue to examine how community resources and policy reforms influence reproductive coercion prevention and its impact on sexual and reproductive health. Sustained collaboration among nurses, researchers, clinicians, and community partners will be essential to translating this knowledge into evidence-based strategies