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Supplemental Materials: Effects of Medium Components on the Bulk Rheology and on the Formation of Ferning Patterns for Biofilm of Pseudomonas aeruginosa
No full textPseudomonas aeruginosa is a ubiquitous bacterium that has an incredible ability to survive in various extreme environments and to persist despite bombardment by all types of antimicrobial agents. Its virulence and success within a broad range of hosts are largely thanks to the strength of its biofilms. The rheology of biofilm of P. aeruginosa was measured to investigate the bacterial response to nutritional conditions (medium that was modified with glycerol, glucose, sucrose, sodium chloride, and silver nitrate). The elastic modulus and the yield stress of the biofilm of P. aeruginosa increased in response to increases in glycerol, glucose, and sodium chloride. Alternatively, silver nitrate and glycerol inhibited biofilm formation at concentrations that were greater than 0.1 mM and 10 v/v%, respectively. While the addition of sucrose did not affect the biofilm rheology, it did alter the ferning pattern of the biofilm. Ferning patterns form as a result of diffusion-limited desiccation of the salt-macromolecule solution. Ferning coverage of about 50% and a ferning complexity score of 5 were found for most of the biofilm samples. The complexity increased with modifications that caused strengthening of the biofilm, while the coverage and complexity dropped to zero when no biofilm growth was observed due either to inhibition or to incomplete drying. The birefringent bundles of liquid crystals in the biofilm gained a new level of complexity and order within the ferning pattern that correlates with the biofilm robustness as characterized by its rheology, and these properties are heavily influenced by the nutritional environment of P. aeruginosa
AID: An automated detector for gender-inclusivity bugs in OSS project pages
Get PDFThe tools and infrastructure used in tech, including Open Source Software (OSS), can embed “inclusivity bugs”—features that disproportionately disadvantage particular groups of contributors. To see whether OSS developers have existing practices to ward off such bugs, we surveyed 266 OSS developers. Our results show that a majority (77%) of developers do not use any inclusivity practices, and 92% of respondents cited a lack of concrete resources to enable them to do so. To help fill this gap, this paper introduces AID, a tool that automates the GenderMag method to systematically find gender-inclusivity bugs in software. We then present the results of the tool’s evaluation on 20 GitHub projects. The tool achieved precision of 0.69, recall of 0.92, an F-measure of 0.79 and even captured some inclusivity bugs that human GenderMag teams missed.Index Terms—Gender inclusivity, automation, open source, information processin
Supporting Statistical Models for Fluorescence Spectrometry to Quantify Percent Wood Failure in Adhesive Bonds
No full textIncludes Partial Least Squares Regression and Univariate Linear model RStudio code and results in PDF form for each of the three specimen populations scanned by two different light sources. Also included is a generalized PDF document and RMarkdown document for predicting percent wood failure
The Economic Path Dependency of Foreign Extraction Duration: Why Colonialism Still Matters
Get PDFForeign occupation and extraction have arguably existed since the very emergence of interstate conflict millennia ago. Yet despite humanity’s vast experience on the topic, we know surprisingly little about its long-term economic consequences. It is generally accepted by most that the extraction of resources by a foreign power tends to hurt the economic prospects of those being occupied, however there has been remarkably limited direct analysis of the nature of this apparent relationship. While there is little doubt that such extraction does indeed cause subsequent economic hardship well into the future, the application of contemporary economic analysis to this relationship may be useful in understanding how to potentially mitigate its causes and effects in the future. This paper seeks to identify the relative proportionality of this relationship using modern measures of economic performances against historic legacies of foreign extractive institutions
Συσχέτιση Σεισμικών Παραμέτρων και Ολικών Δεικτών Βλάβης σε Κατασκευές Οπλισμένου Σκυροδέματος
Get PDFIn the present work, a correlation is made between seismic intensity parameters and total damage indicators of reinforced concrete structures. For this purpose, natural ground motions recordings were used, from which intensity measures were calculated and alternatives were proposed. Then, through dynamic inelastic time history analyzes, damage indices were evaluated for 1st and 2nd order theory (P-Delta effects). The correlation between each seismic parameter and the corresponding damage index was made through polynomial regressions. Seismic parameters that do not take into account the characteristics of the building, showed a minimal or moderate correlation, while spectral parameters of velocities and energies explain the change of damage indices in percentages above 80 or even 90 per cent.Στην παρούσα εργασία πραγματοποιείται συσχέτιση μεταξύ σεισμικών παραμέτρων έντα-σης και ολικών δεικτών βλάβης σε κατασκευές οπλισμένου σκυροδέματος. Για αυτόν τον σκοπό, χρησιμοποιήθηκαν καταγραφές πραγματικών σεισμών, από τις οποίες υπολογίστηκαν παράμετροι, που χαρακτηρίζουν ένα επιταχυνσιογράφημα και προτάθηκαν εναλλακτικές τους. Στη συνέχεια μέσω δυναμικών ανελαστικών αναλύσεων χρονοϊστορίας αποτιμήθηκαν δείκτες βλάβης για θεωρία 1ης και 2ης τάξης. Η συσχέτιση μεταξύ του εκάστοτε ζεύγους σεισμικής παραμέτρου και δείκτη βλάβης έγινε μέσω πολυωνυμικών παλινδρομήσεων. Σεισμικές παρά-μετροι που δεν λαμβάνουν υπόψη τους τα χαρακτηριστικά του ταλαντωτή, παρουσίασαν ελάχιστη ή μέτρια συσχέτιση, ενώ φασματικές παράμετροι ταχυτήτων και ενεργειών ερμη-νεύουν τη μεταβολή των δεικτών βλάβης σε ποσοστά άνω του 80 ή και 90 τοις εκατό
Physical fitness for the few or physical activity and health for all: Coexisting ideologies or Pushmi-Pullyu tensions in the quest for building an active, health nation?
Get PDFIs it better to have a select few people serve as representatives of a nation’s health and vitality, or to have the whole of a nation be active and healthy? The answer speaks volumes about a society’s values and long-term interests in its citizens and their prosperity. If the emphasis is on a select few, then an illusion of a healthy and active society can be created. The mass public can bask in the reflective glory of the achievements of the representative few, but they themselves may never know or experience true health, happiness, or prosperity. This presentation will consider the value propositions associated with this question from the perspective of: (a) the academic discipline of physical education; (b) 21st century diseases, 19th century wisdom; (c) understanding physical activity behavior: psychosocial and sociocultural perspectives; (d) isotemporal substitution model; (e) sociocultural relevancy model and community-based participatory research; and (f) syndemic nature of hypokinetic diseases and sedentary death syndrome. To positively affect change among the masses, those involved in delivering physical activity interventions and programming must not only address each lifestyle behavior and social affliction that contributes to hypokinetic diseases, but also to the social and environmental forces that link those causes together (e.g., stigma, unequal access to resources).
The aim of this presentation is to critically reflect on where the discipline of physical
education has been and to offer suggestions about where it is going, with a keen interest in
advancing inclusive physical activity practices that benefit the whole of society. The
complexities of physical inactivity-related diseases will be discussed, leading to
recommendations for assuring the sociocultural relevancy of the work that is being done, work
that can be enhanced by employing community-based participatory research methods
Neutron Capture Cross Sections of Cadmium Isotopes
Get PDFThe neutron capture cross sections of ¹⁰⁶Cd, ¹⁰⁸Cd, ¹¹⁰Cd, ¹¹²Cd, ¹¹⁴Cd and ¹¹⁶Cd were determined in the present project. Four different OSU TRIGA reactor facilities were used to produce redundancy in the results and to measure the thermal cross section and resonance integral separately. When the present values were compared with previously measured values, the differences were mostly due to the kind of detector used or whether or not the samples were natural cadmium. Some of the isotopes did not have any previously measured values, and in that case, new information about the cross sections of those cadmium isotopes has been provided
Development of a Brownian motion experiment for an undergraduate laboratory course
Get PDFA new class at Oregon State, PH 317: Experimental Physics, is designed to simulate a traditional laboratory research experience for undergraduate students. Several weeks of the class is devoted to Brownian motion experiments. Although this is a common topic for undergraduate lab classes, the experiment still needed some basic exploration to fill in the gaps of existing laboratory literature before the class could be taught. Five different suspensions of uniformly manufactured polystyrene spheres, ranging in diameter from 0.51- µm to 3-µm, were diluted and examined at 40x magnification on separate microscope slides. The motion on these slides were recorded at three different depths, and these recordings were measured using an analysis software. From these measurements, the diffusion coefficient could be calculated and compared to the theory. These measurements were repeated over five days. The results indicate a clear drop in diffusion coefficient at the edges of the slide versus the center, as expected. While the spheres above 1-µm in diameter stopped moving after a few days, the smaller particles remained surprisingly consistent in their measurements, even after five full days. This result means that students do not need to create a new slide if they want to take data over multiple class sessions, as had previously been assumed. All the values obtained through this project provide a strong reference range for what students should expect while doing this experiment
The Weinstein Effect: The Role of MeToo Movement in Altering the Communication Strategies of Members of Congress
Get PDFIn this paper, we explore the effect of critical events in shaping the responsiveness of elected officials to gender issues. In particular, we explore whether U.S. House Representatives discuss women’s issues more after the outing of Harvey Weinstein as a sexual harasser and the growth of the MeToo movement. To explore the impact of the Weinstein accusations and the movement that followed, we assess members of Congress’ discussions about gender issues on twitter before and after October 2017. Through our analysis of over 150,000 tweets from 409 U.S. House Representatives from the 115th Congress, we show that on average U.S. House Representatives were more likely to discuss women’s issues after the Harvey Weinstein incident. This change in focus on gender issues is driven primarily by female Democratic elected officials. Contrary to our expectations, the race/ethnicity of the female legislator did not predict changes in discussions of women’s issues above and beyond partisanship. Overall, we find evidence that critical events can have immediate and long-lasting effects on the communication strategies of members of Congress
Deriving relationships between number of observed short gamma ray bursts and viewing angle
Get PDFGamma ray bursts are some of the brightest events in the entire observable universe. Since the late 1960’s, thousands of gamma ray bursts have been observed and they have been researched extensively. However, there are still many mysteries which remain unsolved. One such mystery is whether or not the viewing angle, more specifically the off-axis viewing angle, of short gamma ray bursts affects the distribution of bursts. It has been suspected that at least some of the features of the gamma ray burst distribution are due to off-axis viewing (meaning the burst was observed at large angles relative to its propagation direction). In this study, Monte-Carlo simulations were used to determine the relationships between the number of observable short gamma ray bursts and the flux of those bursts based on randomly generated viewing angles. Here we show that the viewing angle is a primary contributor of the shape of the distribution of short gamma ray bursts. Other effects include the geometry of the universe, its expansion rate, and its star formation rate. Understanding this relationship will allow for better contextualization of the experimental data that has been gathered for the past 50+ years. Further studies should be done to exclude some of the other parameters that affect the distribution, such as distance, in order to further refine the relationship between viewing angle, flux, and number