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Progress Towards New Antimicrobial Agents
No full textBacterial and fungal infections are among the greatest causes of death worldwide. With the continued growth of drug-resistant antimicrobials comes a greater challenge fighting these “superbugs”. Because of this, the need for new and alternative pathways for fighting these diseases is both necessary and prevalent. Previous work from our lab has explored extracts of the Argemone mexicana plant to identify key molecules that give the plant its antimicrobial properties. Our current work centers around berberine, one of the key molecules, and designing and synthesizing structural variants. Several of our prior variants showed marked improvement over the plant-derived compound against gram-positive bacteria. The goal is to continue generating new and more potent antimicrobial drugs. Much of the recent work is focused on expanded hydrophobic units in the variant structures. The compounds discovered in this work may lead to the development of more selective antimicrobial drugs
The Origin of Unidentified Infrared Emission Lines in Planetary Nebulae Environments
Get PDFPlanetary nebulae emit unidentified infrared emission (UIE) lines that come from an unknown source. A proposed source for these UIE lines is polycyclic aromatic hydrocarbons (PAHs) which are composed of fused carbon rings. We have calculated the absorption spectra from various PAHs and compare them to observed UIE lines to try to determine where the UIEs come from. Our goal is to observe how ionization and nitrogen or oxygen heteroatom substitutions affect the infrared (IR) spectrum. We used the Gaussian 09 program to calculate the structures and IR absorption spectra for about ninety different PAHs. These include linear and non-linear fused ring structures and nitrogen and oxygen substitutions, both in neutral and ionized states. We determined the vibrational modes associated with each of the peaks observed in the IR spectra. These modes involve C-H stretching, C-C stretching and both in-plane and out-of-plane C-H bending modes. Oxygen and nitrogen substitutions tend to increase the intensity of of the C-C stretching and C-H in-plane bending modes. We also determined that PAH molecules must have hydrogen atoms with specific numbers of neighboring hydrogen atoms in order to match the observed UIE bands. While none of the molecules we have studied match the UIE bands exactly, our results limit possible candidates for PAHs that can reproduced the major UIE peaks in planetary nebulae spectra
Algorithm for Predicting Bitcoin Fees
Get PDFBitcoin was designed to be a decentralized peer-to-peer cash system, which creates scarcity in two ways: the total supply of Bitcoin available, and the block size of each block. The blocks, which form what is called the Bitcoin Blockchain, can contain at most 4 MB of data. Since the size of blocks is limited, and each transaction takes up some size, the number of transactions included in a block is necessarily limited. To combat this, users incentivize their transaction to be included in a block through a transaction fee, or the price the transactor pays a miner to include their transaction in a mined block. The miner, by validating the transaction and including it in a block can claim the fee as compensation. This price is typically quoted in satoshis per virtual byte or sat/vB. This will be the primary target unit for our fee estimation algorithm. What we propose is combining several data sources of current blockchain activity to predict the optimal fee. This approach is purely empirical, not relying on a theoretical model or explicitly estimating the time that the next block will be found. Additionally, we will also display the results of said algorithm to a monitor, utilizing MLFlow, so as to best visualize our results. This will enable us to better predict the costs of Bitcoin mining
NSE Bus Emulator for Valparaiso University ThinSat Project
Get PDFThe Valparaiso University Satellite Project is developing a 0.5U ThinSat payload in partnership with Near Space Launch (NSL). This abstract highlights the NSE Bus Emulator, a critical testing platform that replicates the NSL ThinSat bus interface.
Our emulator consists of a custom-designed PCB, fabricated through JLCPCB with SMD components pre-assembled, integrated with an Arduino Mega. The hardware provides identical mounting and connector configurations to the actual ThinSat bus, supplying regulated power rails (3.3V, 5V, and BUSS6-9V) with current measurement capabilities and software-controlled power switches.
The software builds upon NSL\u27s proprietary Arduino code, enhanced by our faculty advisor to improve power switching control and transmission command handling. These modifications enable accurate simulation of the ThinSat bus behavior.
This emulator is essential for testing our satellite\u27s communications system, which uses both NSL\u27s Iridium-based S4 radio and a custom antenna for downlinking data to SatNOGS ground stations. Through the emulator, we can simulate uplink commands, test payload responses, and verify power consumption before integration with flight hardware.
Beyond its technical function, the emulator provides students with practical experience in PCB design, embedded systems programming, and hardware-software integration. As we progress toward launching our first satellite, the NSE Bus Emulator remains critical for final validation testing, ensuring mission success while building capacity for future space science research at Valparaiso University
Perspective - Leadership and Management
Get PDFWhy do we care?
Leadership is a word on everyone’s tongue. A hackneyed word. A much bantered about word. A word that engenders “good feeling”. A word that denotes reaching the pinnacle. A word akin to soaring heights. An Icarus word. A word that implies others will follow. A Pied Piper word.
But what is our view of leadership from below? What inspires us to be led? What makes us strive for this pinnacle? And why do we care? And why do we ignore that the leader might not be one of us?
In this article, we explore the origin of the words leadership and management; discuss their attributes and differences; propose a comparative personal schema for leadership; and highlight the five essential traits of leadership
Factor Analysis of the Cultivated Leadership Questionnaire (CLQ) and Measurement Against the Short Dark Triad (SD3)
Get PDFThis study aimed to evaluate the Cultivated Leadership Questionnaire (CLQ), a self-report tool designed to assess leadership based on key constructs such as self-regulatory behaviors, emotional intelligence, prosocial actions, positive motivational strategies, and personal influence. An exploratory factor analysis identified two main components that together accounted for 65.44% of the variance, suggesting a general leadership factor and a secondary factor capturing more specific leadership attributes. The study also examined the relationship between Dark Triad traits—psychopathy, narcissism, and Machiavellianism—and the leadership behaviors measured by the CLQ. The results revealed negative correlations between both Machiavellianism and psychopathy with leadership behaviors, while narcissism did not demonstrate any significant correlations
Susceptibility of English Oak (Quercus robur) to the Twolined Chestnut Borer, Agrilus bilineatus (Coleoptera: Buprestidae): Observations from Michigan
Get PDFThe twolined chestnut borer, Agrilus bilineatus (Weber), is a native North American buprestid beetle that normally infests oak (Quercus) trees stressed by drought or defoliation. However, during the 1980s and early 1990s, A. bilineatus preferentially infested English oak (Quercus robur L.) trees that initially appeared healthy at two experimental plantings in southern Michigan as well as on the Michigan State University (MSU) campus in East Lansing, Michigan. At both experimental plantings the English oaks were intermixed with native white oaks (Quercus alba L.) and had a border of native northern red oaks (Quercus rubra L.). At both locations, only the English oaks showed evidence of A. bilineatus infestation. Significantly more A. bilineatus adults were captured on sticky band traps on English oaks with low or depleted root starch levels compared to trees with medium to high starch levels. For one of the experimental plantings that was monitored for five consecutive years, 29 English oak trees eventually died that appeared healthy during the first year of observation: 3 (10%) died in one year, 20 (69%) in two years, 4 (14%) in three years, and 2 (7%) in four years. Of 403 English oak trees at MSU that were rated for crown dieback typical of A. bilineatus infestation, 37% showed some level of dieback in 1990, and 60% in 1991. As of 2024, as many as 157 of the original 403 English oak trees are still alive on the MSU campus, with most living trees having been treated with systemic insecticides. These results are discussed in terms of the “naïve host” theory in which plants may have lower resistance to herbivores that they did not coevolve with
