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In situ Additive Manufacturing (AM) Monitoring Using Complementary Metal Oxide Semiconductor (CMOS) Technology
No full textResearch into vision and image sensing techniques has resulted in innovative in situ monitoring techniques such as imaging using thermal cameras and pyrometry. However, these techniques are not currently being used to detect defects or monitor processes in commercial desktop-type FDM printers as they are considered too expensive for these printers. Affordable, innovative, and reliable in situ monitoring processes must be developed to improve the build quality in Additive Manufacturing. This project utilized Complementary Metal Oxide Semiconductor (CMOS) sensors and integrated computing, incorporated into a desktop-type FDM AM printer. The methodology involved creating a closed control loop around an FDM printer with a programmable Integrated Circuit (IC) as the controller and a CMOS sensor as the sensing input device. The CMOS sensor (camera) was used to capture an image of the build platform with the printed part after specific layers, and the image is sent to the microcontroller. The controller processes this image as well as the image from the printer’s input file and converts both images to histograms. The conversion to histograms occurs by creating bins on the horizontal axis of a graph to represent different image pixel intensities. Histograms are compared and assigned a correlation factor. If this assigned correlation factor falls within the user’s pre-defined threshold, the printer is instructed to build the next layer, otherwise, the printer is instructed to pause or stop printing
A Phenomenological Investigation of African American Women\u27s Views on the United States of America\u27s Healthcare System
No full textAfrican American Women experience racial discrimination throughout their life course, and its effects result in complex trauma, cultural mistrust of the healthcare system, and preventable chronic illness. The evolving stereotypes and targeting of Black women are evidence of the pervasiveness of racism. Present in the healthcare infrastructure is the Angry Black woman and Strong Black woman stereotypes, which has created a shortage of social justice efforts towards eliminating healthcare disparities and exposing inadequate provision of medical care. Highlighting the challenges that Black women encounter in their medical care contributed to the existing research. This study hoped to inspire momentum towards creating strategic and realistic plans to resolve healthcare disparities, acknowledge systemic flaws, and for clinicians to check repressed biases. Black women in this study shared their experiences with systemic racism in their medical treatment. Specifically, the results showed that implicit bias, discrimination, and stereotyping, all of which resulted in a negative impact on psychological and physical wellbeing over an extended period. The majority of participants reported episodes of anxiety, anger, depression, and gaslighting. All participants discussed their experiences battling the high-pain threshold, Strong Black Woman, and Angry-Black Woman stereotypes when dealing with the healthcare system. A consistent and supportive stereotype was the Strong Black woman, which was endorsed as a means of protection from provider discrimination and anticipated harm. The Strong Black Woman image enhanced participants’ odds of survival. All participants identified as Strong Black Women and shared that the adoption of strength is a cultural responsibility. Future research should continue to investigate Black women’s experiences in the healthcare system. Black women shared their needs and desire for advocacy in their medical care. If White providers worked on repressed biases and leaned in towards allyship, this could be a foundational step towards closing the healthcare disparity gap
Evaluation of Wave Contributions in Hurricane Irma Storm Surge Hindcast
Get PDFThis paper evaluates the contribution of waves to the total predicted storm surges in a Hurricane Irma hindcast, using ADCIRC+SWAN and ADCIRC models. The contribution of waves is quantified by subtracting the water levels hindcasted by ADCIRC from those hindcasted by ADCIRC+SWAN, using OWI meteorological forcing in both models. Databases of water level time series, wave characteristic time series, and high-water marks are used to validate the model performance. Based on the application of our methodology to the coastline around Florida, a peninsula with unique geomorphic characteristics, we find that wave runup has the largest contribution to the total water levels on the south and northeast coasts. Waves increase the surge on the south and northeast coasts, due to large fetch and wave runups. On the west coast, the wave effect is not significant, due to limited fetch. However, significant wave heights become greater as the waves propagate into the deep inner gulf. The continental shelf on Florida’s west coast plays a critical role in decreasing the significant wave height and sheltering the coastal areas from large wave effects. Both models underpredict the high-water marks, but ADCIRC+SWAN reduces the underprediction and improves the parity with the observed data, although the scatter is slightly higher than that of ADCIRC
A Critical Race Exploration of Black Women’s Romantic Relationship Experiences
No full textCritical race theory was applied in this qualitative phenomenological study to explore the romantic relationship experiences of African American women. In addition to factors central to critical race theory such as race, racism, oppression, and power (Delgado & Stefnacic, 2001; Rollock & Dixson, 2016), this study also considered implications of familial processes and cultural experiences unique to Black women regarding their romantic relationship expectations and outcomes. In congruence with critical race theory and qualitative phenomenological research methods, findings of this study were based on the lived experiences of Black women, providing them the authority to share their own narratives (Creswell & Poth, 2016; Parker, 1998; Parker & Lynn, 2002; Sundler et al., 2019; Wertz, 2005). Participant interviews examined participants’ familial processes and experiences with racism and oppression, as they pertain to the formation and maintenance of family structure and romantic partnerships. Primary data was collected through semi-structured participant interviews with nine Black women. All interviews were recorded and transcribed for analysis, using thematic analysis methodologies to code data and identify emergent themes (Braun & Clark, 2006; Norwell et al., 2017). Five themes emerged from the data: (Theme 1) family dynamics limited romantic relationships; (Theme 2) family messages about womanhood and colorism; (Theme 3) stereotypes, (Theme 4) media portrayals, and (Theme 5) faith messages
The EXPRES Stellar Signals Project II. State of the Field in Disentangling Photospheric Velocities
Get PDFMeasured spectral shifts due to intrinsic stellar variability (e.g., pulsations, granulation) and activity (e.g., spots, plages) are the largest source of error for extreme-precision radial-velocity (EPRV) exoplanet detection. Several methods are designed to disentangle stellar signals from true center-of-mass shifts due to planets. The Extreme-precision Spectrograph (EXPRES) Stellar Signals Project (ESSP) presents a self-consistent comparison of 22 different methods tested on the same extreme-precision spectroscopic data from EXPRES. Methods derived new activity indicators, constructed models for mapping an indicator to the needed radial-velocity (RV) correction, or separated out shape- and shift-driven RV components. Since no ground truth is known when using real data, relative method performance is assessed using the total and nightly scatter of returned RVs and agreement between the results of different methods. Nearly all submitted methods return a lower RV rms than classic linear decorrelation, but no method is yet consistently reducing the RV rms to sub-meter-per-second levels. There is a concerning lack of agreement between the RVs returned by different methods. These results suggest that continued progress in this field necessitates increased interpretability of methods, high-cadence data to capture stellar signals at all timescales, and continued tests like the ESSP using consistent data sets with more advanced metrics for method performance. Future comparisons should make use of various well-characterized data sets—such as solar data or data with known injected planetary and/or stellar signals—to better understand method performance and whether planetary signals are preserved
Complex Role of Microbiome in Pancreatic Tumorigenesis: Potential Therapeutic Implications
Get PDFPancreatic cancer (PC) is the fourth leading cause of cancer-related mortality with limited diagnostic and therapeutic options. Although immunotherapy has shown promise in the treatment of several cancers, its role in pancreatic cancer is rather limited. Several studies have focused on determining the role of the tumor microenvironment with cancer-cell-intrinsic events and tumor-infiltrating immune cellular properties. However, in the past decade, there has been emerging research aimed at delineating the role of the host microbiome, including the metabolites from microbes and host responses, on pancreatic tumorigenesis. Importantly, there is emerging evidence suggesting the beneficial role of a gut microbiome transplant to improve immunotherapeutic outcomes in cancer patients. In this review, we summarize the recent understanding of the role of the microbiome in pancreatic cancer progression, along with its clinical diagnostic and therapeutic implications
