Polysaccharides of St. John’s Wort Herb Stimulate NHDF Proliferation and NEHK Differentiation via Influence on Extracellular Structures and Signal Pathways

St. John's Wort herb extracts often contain undesirable or volitional polysaccharides. As polysaccharides exhibit structure-dependent biological functions in the present study water-soluble polysaccharides were extracted from herb material, fractionated by anion exchange chromatography into four main polysaccharide fractions (denominated as Hp1, Hp2, Hp3 and Hp4) and characterized by HPAEC-PAD, CE, IR and GC-MS. Biological activity on human skin keratinocytes and fibroblasts was assessed by investigation of their effect on proliferation, metabolism, cytotoxicity, apoptosis and differentiation. The underlying mechanisms were investigated in gene expression studies. Polysaccharide fraction Hp1 was mainly composed of β-D-glucose. Hp2, Hp3 and Hp4 contained pectic structures and arabinogalactan proteins varying in composition and quantity. Polysaccharides of Hp1 induced the keratinocyte differentiation by inhibiting the gene expression of the epidermal growth factor and insulin receptor. While the collagen secretion of fibroblasts was stimulated by each polysaccharide fraction only Hp1 stimulated the synthesis. The fibroblast proliferation was reduced by Hp1 and increased by Hp4. This effect was related to the influence on genes that referred to oxidative stress, metabolism, transcription processes and extracellular proteins. In conclusion polysaccharides have been shown as biologically active ingredients of aqueous St. John's Wort extracts with a relation between their structural characteristics and function

Building Undergraduate Research in a Fully Online Engineering Program

This paper describes the creation and implementation of the support network of the Research Scholars Program at the Worldwide campus of Embry-Riddle Aeronautical University. Funded by an NSF IUSE grant, the purpose of this new program is to increase the opportunity for online engineering and engineering technology students to participate in undergraduate research. Studies have shown that participation in research can have an important impact on students, though online students are likely underrepresented in undergraduate research. The Research Scholars Program uses existing support systems of the campus while also building new components. These new components developed for this project are a research mentoring program, a workshop series, and a guided independent study course. The Research Scholars Program formalizes the process for online students at the Worldwide campus to participate in undergraduate research with a goal of having students publish and present their work

The Fine Guidance Sensor, An Electronic Scanning Star Tracker

The advent of space exploration has placed hitherto unheard of requirements on accuracy and precision sensing devices for guidance and attitude control. The necessity for high reliability, due to non-repairability, required new approaches to this design problem. Rather than try to improve upon existing systems, components, and approaches, a totally new concept evolved which eliminates the mechanical rotors and reticles of yesterday. Instead, a totally new breed of electronic scanning star sensor resulted. This paper describes one such device, a Boresighted Star and Planet Tracker developed for precise attitude sensing and control of an experimental sounding rocket. Discussed are the major elements of the basic sensing system, optics, detector, and electronics. The heart of the new sensor is the electronic scanning multiplier phototube, a small, rugged, highly accurate and highly reliable device. Electronic circuit design to enhance accuracy and precision is outlined

What does it mean to be “prepared for work”? Perceptions of new engineers

Background: Engineering education seeks to prepare students for engineering practice, but the concept of preparedness is often ill-defined. Moreover, findings from studies of different populations or in different contexts vary regarding how well new graduates are prepared. These variations, coupled with the lack of clarity, suggest the need to better understand what it means to be prepared for engineering work. Purpose: This study contributes to research on workplace preparation by exploring how new graduates describe being prepared for engineering work. Method: Applying secondary analysis to data from the multi-institution Capstone To Work (C2W) project, we used thematic analysis to explore new engineers\u27 descriptions of preparedness. We analyzed written responses to structured questions about the school-to-work transition collected weekly during participants\u27 first 12 weeks of work; 105 graduates drawn from four universities provided 956 responses, with a mean of 9 (out of 12 possible) responses per participant. Results: Participants\u27 descriptions of preparedness included applying concrete skills, recognizing familiar situations, and having strategies for approaching challenging tasks even when they lacked relevant knowledge or skill. Conclusion: Our findings suggest that although many discussions about workplace preparation implicitly focus narrowly on mastery of skills and knowledge, that focus may not fully capture new graduates\u27 experiences, and may limit discussions about the ways in which school can (and cannot) prepare students for work. A more expansive understanding may better support both student learning and workplace onboarding, though more research is needed across stakeholders to establish shared understanding

Board 256: Development and Evolution of Workshops to Support Online Undergraduate Research

Under a National Science Foundation (NSF) Improving Undergraduate STEM Education (IUSE) grant, the Research Scholars Program was developed at Embry-Riddle Aeronautical University — Worldwide. The objective of the Research Scholars Program is to promote undergraduate research for the online students at the Worldwide campus and to formalize the process in which the students can participate in research. A significant aspect of the project was to create a support network for the students that incorporated existing services provided by the university and established new services to aid students throughout their mentored research experience. One of the new services was the development and delivery of starting in the second year of the grant and continuing through the third year. The purpose of the workshops is to introduce students to different aspects of research. The first series of workshops (offered in the 2021-2022 academic year) were mostly informational and provided initial support for undergraduate researchers. From the experience of developing and hosting the first series, the style of the second series (offered in the 2022-2023 academic year) was modified to try to promote more audience participation

Aerodynamic and Aeroacoustic Performance of Small UAV Propellers in Static Conditions

The proliferation of small multi-rotor UAVs in commercial, recreational, and surveillance spheres has garnered significant interest in the noise produced by these vehicles. The current research aims to study the relationship between the aerodynamic performance and acoustic characteristics of small-scale UAV propellers. Three commercially available propellers for the DJI Phantom 2/3 UAV were selected for preliminary development and validation of an aeroacoustic experimental test setup and associated data reduction methods. Propeller thrust, torque, and power measurements were recorded at static conditions. Upon successful validation of the test bench, acoustic measurements were taken at the propeller disk’s upstream and in-plane locations. The power spectral density of these acoustic signals was estimated using the modified periodogram (Welch’s) method to identify frequency content and calculate sound pressure levels (SPLs) at each of the observation locations. Additionally, time-frequency analysis verified the periodogram results and identified possible sources of transient noise at static thrust. These methods found the nonrotor noise to be a major contributor to the SPL at higher frequencies and the propeller noise dominating the SPL spectra at the lower frequencies. Experimental thrust, torque, power, and sound pressure level (SPL) data were then compared for each propeller to identify relationships between aerodynamic performance and acoustic characteristics with variations in propeller geometry and blade loading