Effects of 1,25-Dihydroxyvitamin D₃ on adipocyte differentiation

Several recent reports from this laboratory demonstrate a regulatory role for intracellular Ca2+ ([Ca2+]1) in modulating lipid metabolism in both human and murine adipocytes, with increased [Ca2+]1 coordinately stimulating lipogenesis and inhibiting lipolysis, thereby expanding lipid mass. Further, we have recently demonstrated that 1,25-dihydroxyvitamin-D3 [1,25-(OH)2-D3] stimulates adipocyte membrane vitamin D receptor (mVDR)-mediated rapid Ca2+ influx into adipocytes, resulting in the stimulation of lipogenesis and inhibition of lipolysis. However, increasing [Ca2+]1 in the early stages of differentiation inhibits human adipocyte differentiation, whereas increasing [Ca2+]1 in the late stage promotes human adipocyte differentiation Accordingly, we have investigated the role of 1,25-(OH)2-D3 in the differentiation of 3T3-L1 preadipocytes, using triglyceride (TG) accumulation and glycerol-3-phosphate dehydrogenase (GPDH) as markers. 3T3-L1 preadipocytes were placed in differentiation media upon confluence, and exposed to varying amounts (0, 1nM, and 10nM) of 1,25-(OH)2-D3 for either one-hour pulses or for sustained (24 hrs or 48 hrs) amounts of time throughout the differentiation process Exposure to one-hour pulses of 1nM 1,25-(OH)2-D3 throughout differentiation caused modest decreases (31%-38%) in TG accumulation (p\u3c0.0001), with one-hour pulse exposure to 10nM 1,25-(OH)2-D3 having little to no effect on TG accumulation. One-hour pulse exposure to both 1nM and 10nM 1,25-(OH)2-D3 suppressed GPDH activity early, but not late in differentiation. Sustained (24-hour) exposure to 1,25-(OH)2-D3 (1nM and 10nM) inhibited differentiation at 0-24 hrs, with decreases in both TG and GPDH of 41-81% (p\u3c0.0001). Similarly, sustained exposure of 1,25-(OH)2-D3 resulted in marked inhibition of GPDH activity and TG accumulation early in differentiation. In contrast, sustained exposure late in differentiation exerted no significant effects on either marker of differentiation PPAR-γ and pref-1 expression were also used as markers of differentiation. One-hour pulses of 10nM 1,25-(OH)2-D3 did not cause any changes in PPAR-γ expression compared to control. Sustained exposure to 1,25-(OH)2-D3 throughout differentiation decreased PPAR-γ expression, with a 92% decrease from 0-48h (p\u3c0.0001). One-hour pulses of 1,25-(OH)2-D3 had no effect on Pref-1 expression, with the exception of an increase in expression at 47-48 hr (p\u3c0.0001). Sustained exposure to 10nM 1,25-(OH)2-D3 at 0-48 hrs, 24-48 hrs and 47- 48 hrs all caused significant increases (125%-146%) in the expression of Pref-1 (p\u3c0.001). Thus, although 1,25-(OH)2-D3 stimulates lipogenesis, inhibits lipolysis and increases TG accumulation in mature human and murine adipocytes, it also modestly inhibits the differentiation of preadipocytes into mature adipocytes

GPS Micro Navigation and Communication System for Clusters of Micro and Nanosatellites

Formation flying will quickly revolutionize the way science, remote sensing and surveillance missions are performed in space, enabling a whole new range of applications for small satellites. Currently, there are numerous missions in the planning stages involving formation flying of a constellation of micro or nanosatellites. However, to truly achieve the goals of these formation-flying missions, an accurate means of relative ranging, determining time and position measurements, inter-satellite communications, and controlling the formation states is becoming critical. Today, while there are very expensive products available for positioning and attitude determination, none of them are capable of meeting the precise positioning accuracy and attitude determination requirements of formation flying, let alone the mass and power restrictions of these tiny space vehicles. This paper will address the needs of future formation flying missions by discussing a technology with integrated capabilities for communicating, relative ranging, and exchanging precise timing among spacecraft within the constellation. This system is being developed by integrating a Carrier Phase Differential GPS (CDGPS) navigation and attitude sensor with a low power, inexpensive, compact ranging and communications system. The result of this integration is a low-cost, robust, secure GPS micro navigation and communication system for micro and nanosatellite constellations

Periodic Variation of Stress in Sputter Deposited Si/WSi2 Multilayers

A tension increment after sputter deposition of 1 nm of WSi2 onto sputtered Si was observed at low Ar gas pressures. Wafer curvature data on multilayers were found to have a periodic variation corresponding to the multilayer period, and this permitted statistical analyses to improve the sensitivity to small stresses. The observation of tension instead of compression in the initial stage of growth is new and a model invoking surface rearrangement is invoked. The data also bear on an unusual surface smoothing phenomena for sputtered Si surfaces caused by the sputter deposition of WSi2 . We furthermore report that for low Ar pressures the Si layers are the predominant source of built-up stress

The Relationship Between College Student Characteristics and Reporting Sexual Assault Experiences on Two Different Scales

Though high rates of sexual assault are found on college campuses, prevalence rates between studies can vary considerable by gender, sexual orientation, and other student characteristics. Thus, it is unknown whether these are “true” differences for such characteristics or if there are methodological differences to consider. As such the current study examined whether student characteristics including gender, race, sexual orientation, sexual attraction, Greek affiliation, and relationship status are uniquely associated with reporting on two different sexual assault scales. Data were gathered from 783 college students in 2019–2020 at a large Midwestern university. Results revealed that the two different scales consistently provided different prevalence rates of sexual assault. Moreover, for each type of sexual assault (e.g., coercion, incapacitation, and physical force), there were also significant differences with students consistently reporting higher prevalence rates on one scale over the other. Finally, significant differences were found in prevalence rates across gender, sexual attraction, and Greek affiliated status

Lost in Transmission: Romantic Relationships Mediated by Wireless Technologies

Some estimate that short-messaging-service (SMS) text messaging will reach 9.4 trillion messages per year by 2016, not including billions of messages sent by other forms of texting, such as MMS and iPhone\u27s iMessage service. Research shows that habitually using methods of instant communication in romantic relationships has changed the way we communicate with our partners. Direct or inferred meanings sent electronically are often misconstrued by the “receiver” of the messages. Societal norms such as Texting and Instant Messaging (on social networking sites such as Facebook) have introduced new stressors to communication. This project will present research to analyze how the way society transmits messages in romantic relationships can lead to a change in their meanings and the quality of romantic relationships

Values-based leadership: Culture vs. Strategy

Using Google’s Project Aristotle re:Work framework (2012), psychological safety principles (Edmondson, 1999; Edmondson & Lei, 2014), and Sinek’s (2009) purposeful leadership tenets, this workshop will engage participants in refining a leadership philosophy; in outlining steps to create a values-based culture; and in creating high performing research teams and committees

Managing Uncertainty through Values-Centric Leadership

Crises force leaders to think in the short-term to address immediate needs. In navigating emergencies like COVID-19, it is vital that leaders remain values-focused, especially when considering short-term solutions that inevitably have long-term impact. This presentation examines values-centric leadership in the context of crisis communication, budget reductions, and strategic planning

Social Media and Mental Health in Adolescents and Young Adults: A Systematic Review

The goal of our project is to increase understanding of the link between social media use and mental illness in teens and young adults. Our objective is to write a systematic review of the literature to answer the PICOT questions: (1) In teens and adults, younger than 25 years, what is the relationship between social media use and mental illness? (2) In teens and adults, younger than 25 years, what is the effect of interventions, such as social media as a resource, on mental health promotion and well-being? The motivation for our project comes from the increased use of social media and increased rates of mental health issues in the teen and young adult population. We are developing a systematic review to describe the relationships between social media use and mental health, as well as the use of social media as an intervention. The introduction, methods, and review of literature will be completed by May 2020. The remainder of the project will develop over the 2020-2021 school year and will be completed by May 2021. We will also complete a poster presentation through the University of Akron to present our findings

Risk Factors for Forced, Incapacitated, and Coercive Sexual Victimization Among Sexual Minority and Heterosexual Male and Female College Students

Although college students are at high risk for sexual victimization, the majority of research has focused on heterosexual students and often does not differentiate by victimization type. Thus, little is known about prevalence rates and risk factors for sexual victimization among sexual minority college students and whether the interaction between gender and sexual orientation differs by victimization type. To address these gaps, we examine whether risk factors for three types of sexual victimization (i.e., forced, incapacitated, and coerced) differ by gender (n = 681 males; n = 732 females) and sexual orientation (n = 1,294 heterosexual; n = 119 sexual minority) and whether the intersection of gender and sexual orientation is correlated with these three types of sexual victimization among 1,413 college students. Prevalence rate results revealed significant differences between gender and sexual orientation: Sexual minority females had the highest rates of coerced sexual victimization (58%), and their mean was significantly different from the other three groups (i.e., heterosexual females, heterosexual males, and sexual minority males). For both forced and incapacitated sexual victimization, heterosexual males had significantly lower means than the other three groups. Logistic regression results revealed that child sexual abuse increased the odds of experiencing both forced and coerced sexual victimization for both heterosexual and sexual minority students, whereas increased rates of risky sexual behavior were associated with forced and incapacitated sexual victimization but only for heterosexuals. Finally, heavy drinking increased the odds of experiencing incapacitated sexual victimization for both heterosexuals and sexual minorities

Understanding Daily Depression, Drinking, and Marijuana Use among Homeless Youth using Short Message Service Surveying

We used short message service surveying (SMS) with 150 homeless youth to examine the time ordering of feeling depressed with drinking alcohol, using marijuana, and using substances with friends. Multilevel binary logistic regression results revealed that youth who were depressed earlier in the day were more likely to drink alcohol later that day. Among depressed youth, heterosexual youth were less likely to drink alcohol than lesbian, gay, and bisexual (LGB) youth. Depressed youth had increased odds of using marijuana by a factor of 1.6, while heterosexual youth, compared to LGB youth, were 80% less likely to use marijuana. Females were 82% less likely and heterosexual youth 75% less likely to use substances with friends compared to males and LGB youth, respectively. These findings improve upon prior retrospective studies by using SMS to understand time ordering between feeling depressed and substance use in the same day