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MEMS 411: Mini Syringe Pump
Get PDFIn many research and medical settings, small amounts of liquids are dispensed using syringes. Very often, syringe pumps like those shown in the left image, are used to control the amount (i.e., flow rate) of dispensed/collected fluid. There are single- or multi-style syringe pumps; the one shown is single-style; multi-style have 2-8 parallel syringes that are all pushed/pulled at the same flow rate. However, these syringepumps are bulky and heavy, making them impractical for many experimental setups. Commercial alternatives include very expensive syringe pumps with remote dispensers. Furthermore, it is often necessary to have two syringe pumps operate in parallel and with different flow rates. Dr. Weisensee would like the student team to design and build an alternative to commercial syringe pumps that fulfills the following specifications: • It is light-weight (vertically above an experimental setup (using a clamp ona ½’’ post or ¼-20 screws spaced at 1’’ on a platform)• It can accommodate various sizes of standard plasticsyringes or glass syringes (1ml-50ml)• It can dispense liquid between 1μL/min and 10mL/min(can be achieved by varying the motor speed and/or thesyringe size – final design should have multiple pre-setsin flow rates for multiple syringe sizes)• It accommodates two syringes that operate in parallel,but with different flow rates• The two liquids are dispensed simultaneously using twoconcentric needles (see Fig. 2 for a sketch). The innerneedle should be Luer-connected and G30 or smaller.The outer “needle” could be another needle (G22 orlarger) with Luer connection, or a hollow tube (metal orstiff plastic). The goal is to engulf the inner liquid withthe outer one when forming droplets at the needle tip.• The liquids in the syringes can be heated up to 80°
A Novel, Sponge-Tipped Electrode for Motion-Artifact-Tolerant Recording of High-Quality Electroencephalogram Signals
Get PDFSoft electronic devices and sensors have seen great interest devoted to them for the purpose of recording and analyzing various electrophysiological signals including for the use of electrocardiography (ECG), electromyography (EMG), and electroencephalography (EEG). These newly designed and fabricated soft electrodes offer multiple advantages including the reduction of motion artifacts, lighter weight compared to traditional electrodes, improved comfort, and improved quality and length of use for long-term monitoring. While electrodes for ECG and EMG are planar electrodes to maximize the surface contact, this is not possible for electrodes for EEG due to their inability to penetrate the hair and make contact with the scalp. Therefore, EEG electrodes must have a different construction to circumvent this with the common method being a pillar- or spike- structured electrode. Hereafter, we report an elastomeric, conductive electrode consisting of a sponge-tipped pillar structure for contact of the scalp with a hollowed, column backing to clip into a traditional EEG headset for seamless integration of existing EEG monitoring systems. Our electrode exhibits reduced electrode-skin contact impedance, motion-artifact-tolerant recordings, and is a better option for long-term monitoring of EEG signals compared to commercially used electrodes. Our novel electrode consists of two functional parts bonded together with different material characteristics to utilize the best qualities of each material. One part of the electrode is the sponge-tipped pillar structures connected to a common base arranged in a 3x3 arrangement with the central pillar missing leaving a hole. It is comprised of a polydimethylsiloxane (PDMS) substrate coated with a poly(3,4-ethylenedioxythiophene) polystyrenesulfonate (PEDOT:PSS) conductive polymer using a simple dip-coating process. The pillars were made porous using a sacrificial sugar template that was then leached of the sugar using a hot water bath. The backing of the electrode is comprised of a polymer made of carbon black (CB) and PDMS where a central hollow column is connected to its own base that has been bonded to the base of the PEDOT:PSS coated PDMS functional part. Our novel, sponge-tipped electrode is a promising alternative to commercial electrodes due to its low-cost fabrication, comfortability, and capacity for high-quality, long term electroencephalogram recording
Teaching Evolutionary Principles with AI Image Generators
Get PDFThe purpose of this assignment is for students to practice constructing phylogenies using the principle of parsimony. In this activity, students will use an AI Image Generator to create a grid of images of the same organism and identify a series of traits that vary to build a possible phylogenetic tree
Anticipated Belonging in College: An Intervention to Increase College Access
No full textA secure sense of belonging is a fundamental aspect of student well-being, academic outcomes, and long-term success. Although there is a robust body of research on belonging in students’ current academic environment, little has been done to address the effect of students’ anticipated belonging, or the expectation of how a student (or people like that student) will potentially belong in a future context. This study details the development and testing of an intervention designed to promote anticipated college belonging among high school juniors from low socioeconomic backgrounds. The intervention yielded no significant effect on anticipated college belonging, but the intervention effect size for anticipated college belonging was similar to other belonging intervention studies, suggesting that the small sample size of this initial study may have limited our ability to detect the effect. The participants in the intervention condition did, however, report a significantly higher appreciation of different backgrounds and experiences for college. Additionally, we coded participants’ responses to their open-ended responses and found that participants were able to connect the intervention materials to their own lives in several key ways. Although this iteration of the intervention did not fully produce the intended benefits, understanding the participants’ responses to the intervention material will help in further development of anticipated belonging interventions. Overall, this type of intervention shows promise and future research should continue to work to improve students’ perceptions of their backgrounds and experiences as valuable for college, as one way to improve anticipated college belonging
Wealth-Building for All Children: Convergence and Evidence to Support a Nationwide Policy
Get PDFAmid growing concern about wealth inequality in the United States, many policymakers and researchers have come to see early-life wealth-building policies as potential remedies. This brief discusses convergence in the policy community around a shared vision and principles for such policy, and it connects that vision to research. Child Development Account research, much of it conducted through CSD’s SEED for Oklahoma Kids experiment, suggests the parameters for an inclusive, efficient, and effective policy that would express the community’s shared vision
Goin\u27 Down Swinging: Queer Fury
Get PDFHow can kickboxing uplift a community? How can Queer rage be utilized in community building and artmaking?
As a Queer artist, my work is inspired by my own experiences. Through drawing, printmaking, photography, video, performance, sculpture, and social practice, I dissect my violent upbringing and its lingering threads in my adult life. In this essay, I discuss the two most prominent features of my art practice: Fight and Community. I navigate these ideas through past works, such as a performance piece of me destroying a news article, a short film about institutional homophobia through aliens and immaculate conception, and most prominently, my ongoing social practice project, Queer Fight Club. Through this social practice piece, I investigate the questions posed above by teaching Queer participants how to kickbox
Book Review: Rethinking Participation in Global Governance: Voice and Influence After Stakeholder Reforms in Global Finance and Health
Get PDFWho is entitled to contribute to rulemaking at the international or transnational levels? Rethinking Participation in Global Governance takes an empirical tack, confronting the important and understudied—but methodologically confounding—question of how effectively to improve the representativeness of global governance. The volume’s carefully constructed qualitative studies offer a wealth of insights but few systematic or easily generalizable answers. Nevertheless, the book has much to offer, describing models and techniques to expand participation, offering examples of how various actors in the Global South were able to make use of them, then embedding this description in the push and pull of a scholarly conversation over the efficacy and normative desirability of these reforms
Single-Molecule Orientation Imaging Reveals the Nano-Architecture of Amyloid Fibrils Undergoing Growth and Decay
Get PDFAmyloid-beta (Aβ42) aggregates are characteristic Alzheimer’s disease signatures, but probing how their nanoscale architectures influence their growth and decay remains challenging using current technologies. Here, we apply time-lapse single-molecule orientation-localization microscopy (SMOLM) to measure the orientations and rotational “wobble” of Nile blue (NB) molecules transiently binding to Aβ42 fibrils. We correlate fibril architectures measured by SMOLM with their growth and decay over the course of 5 to 20 min visualized by single-molecule localization microscopy (SMLM). We discover that stable Aβ42 fibrils tend to be well-ordered and signified by well-aligned NB orientations and small wobble. SMOLM also shows that increasing order and disorder are signatures of growing and decaying fibrils, respectively. We also observe SMLM-invisible fibril remodeling, including steady growth and decay patterns that conserve β-sheet organization. SMOLM reveals that increased fibril architectural heterogeneity is correlated with dynamic remodeling and that large-scale fibril remodeling tends to originate from strongly heterogeneous local regions
Navigating Gendered Racism through Coping and Radical Healing: An Interpretative Phenomenological Analysis of Black Women’s Mental Health in Doctoral Programs
Get PDFGendered racism emerges as a pervasive mental health concern among Black women doctoral students. However, there is a scarcity of existing literature on the strategies being used to maintain mental well-being while navigating gendered racism among Black women doctoral students. To address the current gaps in scientific knowledge, this dissertation completed individual semi-structured interviews. Interpretative Phenomenological Analysis (IPA), and the lens of Black Feminist Thought and Intersectionality were used as guiding theoretical frameworks to examine narratives of fifteen Black women doctoral students at universities in the United States. The study findings provided insight into coping strategies and the role of radical healing as a way of resisting oppression while in a doctoral program. Data analysis resulted in three themes describing coping strategies: (1) navigating identity and social dynamics, (2) incorporating coping strategies and wellness, and (3) healing and activism in the pursuit of equity. Healing and activism encompassed strategies of radical healing. Implications for research and practice are offered
Reimagining Parent and Family Engagement for African American Children and their Families
No full textAchievement gaps and mental health disparities for Black children have been written about extensively and still persist. Closure of these gaps have moved at a glacial pace. These disparities have significant implications for one\u27s sense of agency. Black family voice has remained underutilized. Because of this untapped potential, it may be, that the pathway for more equitable outcomes have not been fully understood. Parent and family engagement is associated with positive outcomes, yet, gaps remain in realizing its full impact. Social work is also uniquely positioned to spearhead efforts to address educational concerns and scholars have begun to call upon the field to break its silence around issues of education justice. Additionally, parent engagement plays a significant role in funding and legislation as the Every Student Succeeds Act of 2015 made provisions for parent and family engagement. Thus, this 3-paper dissertation explores engagement and its relationship to academic achievement and social-emotional learning through a mixed methods study along with a new proposed model for school-family partnerships with Black families. Implications for research, practice and policy are discussed