1,644 research outputs found
Hypobranching Induced by Both Environmental Antioxidants and ROS Metabolism Gene Knockouts in Neurospora Crassa
Previous work suggested a role of reactive oxygen species (ROS) metabolism on branch density, the statistical distribution of physical distances between branch points along a growing hypha in Neurospora. Here we report the results of experiments designed to ask more generally about the relationship between ROS and branch density by examining the branching effects of selected ROS metabolism gene knockout mutants as well as the impact on branching of exogenously added antioxidants. In all ROS metabolism mutants tested, growth was shown to branch less densely (hypobranching) when grown at lower temperatures, a shift not observed in the wild-type. Interestingly, this holds true for knockouts of genes expected to reduce ROS as well as those expected to produce them. In addition, in tests on wild type Neurospora, added ascorbic acid produced unusual branching patterns. Hypha exposed to exogenous antioxidants display dose dependent hypobranching with hypha becoming more hypobranched as doses increase. At higher doses, however, the branch distribution becomes bimodal with one maximum continuing to shift toward hypobranching and the second maximum representing a spike of very closely spaced branch points
Adequacy of the passive inflated falling sphere technique
Inflated falling sphere for high altitude sounding at radar sit
Effect of Media and Estrogen on Morphological Change in Candida albicans
Introduction:
Candida albicans (C. albicans), an opportunistic pathogen, lives symbiotically within the intestine of its human host. Temperature and chemical factors have been shown to induce a morphological change in C. albicans from yeast to filamentous form turning C. albicans pathogenic. In this study, we investigated the intestinal cues that might be responsible for the change. We found that different solid media impact the morphological phenotype so we focused on characterizing these before further testing. We tested Estradiol (E2) because of its known linkage to sepsis and higher levels during infections. Experiments were conducted to compare solid agar plates of YEPD, Minimal Media (MM), and Spider Media (SP) for C. albicans growth to choose the best one for further testing with E2 and other factors that could be prone to causing morphological changes.
Methods:
C. albicans was inoculated through streak method on different solid media (YEPD, MM, SP) and incubated at 30â. The effect of 0.1nM E2 on C. albicans morphology was also tested. Morphological changes were assayed through bright-field microscopy.
Results:
Using the three different medias, we found three distinctive phenotypes: A, B, and C. Out of 6 experiments of 14 MM plates, the expressed phenotype was 86% A and 14% inconclusive of the time. 8 experiments of 17 SP plates showed 100% of phenotype B. 6 experiments of 14 YEPD plates presented phenotype C 92% of the time and 8% inconclusive. For E2 trials, 2 experiments, 6 MM plates showed 50% phenotype A and 50% inconclusive. 4 experiments, 10 SP plates had phenotype B 100%. YEPD 2 experiments, 2 plates had phenotype C at 100%.
Conclusion:
We have established experimental conditions of media controls for further testing whether E2 and other cues, such as inflammatory cytokines, have inhibitory or positive effects on the growth of C. albicans
Atmospheric measurements over kwajalein using falling spheres
Atmosphere measurements using falling spheres tracked by rada
Contemporary Rhetoric, Ethics, and Human Rights Advocacy (abstract)
This paper will discuss how rhetorical analysis might interpret current ethics conversation related to governance and re-position some of its touchstone rationales. Specifically, efforts in this paper will apply the ideas of preeminent rhetorician Gerald Hauser (the current editor of Philosophy and Rhetoric) about human rights discourses and of a reticulate (variegated) public sphere to intersection of governance and human rights advocacy.
Specifically, our paper will examine the rhetoric of various âexemplarsâ who advocate for causes and actions pertaining to human rights in particular contexts. In particular, we will incorporate case studies reviewing the public actions of the Russian rock group âPussy Riotâ and the Dutch ultra-right parliamentarian Geert Wilders as rhetors whose discourses serve as grist for comparative analysis. Our comparison of these rhetors is premised on the assertion that concern for how particular individuals advocate for human rights causes âas well as how antagonists obstruct such initiatives âadds significant value to understanding the successes and failures of human rights efforts in particular cultural and national contexts. On one hand, we can grasp how specific international organizations and actors function to develop norms (for example, the rights of the child) and how rights are subsequently articulated in universal declarations and formal codes. But on the other, it becomes apparent that the actual meaning of those rights mutate when âacceptedâ within particular cultures.
A final section of our paper will discuss how contemporary rhetorical analysis might inform the ethics of human rights discourse and advocacy in praxis. In this regard, Gerald Hauser elaborates upon thick and thin moral vernaculars in the context of human rights advocacy; specifically, he takes exponents of thin regime principles (e.g. those codified in the Universal Declaration of Human Rights) to task, emphasizing the importance of discourse that is constructed in the context of rights and âmoral empowerment.
The Effects of Low and High Gravity on Neurospora Crassa
We studied the effects of different gravity levels on Neurospora crassa and its morphology. This research was conducted by simulating low and high gravity effects in different operating procedures. For the low gravity simulation, the experiment was conducted by using a clinostat to constantly disorient the samples at a very slow rate. For the high gravity simulation, N. crassa was subjected to different amounts of g forces by placing the samples in a centrifuge and subjected the samples to increasing amounts of revolutions per minute. The results of these experiments conclude that in low-gravity situations, the N. crassa showed sparse growth and some cytoplasmic failure. In the high gravity situations, the samples showed that at around 1,000 to 2,000 RPMs, there were no changes in the morphology, but at higher RPMs like 3,000 or 4,000, there were some signs of cytoplasmic failure but no noticeable changes to morphology
Fluctuation Analysis of Human Electroencephalogram
The scaling behaviors of the human electroencephalogram (EEG) time series are
studied using detrended fluctuation analysis. Two scaling regions are found in
nearly every channel for all subjects examined. The scatter plot of the scaling
exponents for all channels (up to 129) reveals the complicated structure of a
subject's brain activity. Moment analyses are performed to extract the gross
features of all the scaling exponents, and another universal scaling behavior
is identified. A one-parameter description is found to characterize the
fluctuation properties of the nonlinear behaviors of the brain dynamics.Comment: 4 pages in RevTeX + 6 figures in ep
Students perceptions of cheating in online business courses
Accounting majors enrolled in business courses at two different universities were asked to complete a survey questionnaire pertaining to cheating in online business courses. Specifically, students majoring in Accounting were asked about their awareness online business courses as well as their opinions regarding the credibility of online courses and the effectiveness of different techniques that may be used to prevent cheating. Forty-six percent of students indicated that they had knowledge of students receiving help with an online exam/quiz. Overall, 75 percent of respondents indicated that the most effective technique to prevent cheating on online exams/quizzes is the use of random question generation so every exam is uniquely different. Forty-two percent of respondents disagreed with the statement âOnline courses are less credible than traditional courses.â While the potential for cheating in online courses seems to be well perceived, the perception of actual cheating in online courses seems to vary considerable among the students covered in this study
Strain-Dependent Relationship Between Growth Rate and Hyphal Branching in Neurospora Crassa
In a previous study of branch frequency in Neurospora crassa focused on the wild-type, no relationship between growth rate and the frequency of hyphal branching was observed. In subsequent experiments, it became clear that while this independence is valid for the wild type and most mutant strains, it fails to hold for a subset of morphological mutants. This study distinguishes a subset of Neurospora morphological mutants for their morphological response to altered growth rate. Growth rates are altered using two different methods: reduced temperature and nutrient-deficient media. This should assure that the observed effect is not due to simple conditional mutations in the mutant strains examined. The observed effect provides an additional method for characterizing morphological mutants. It also provides support for models of branching in which control of branching is tightly linked to mechanisms of tip growth
Testing the Potential of Using Fungi to Convert Human Waste into Protein
We report on the results of a pilot experiment designed to test the potential of filamentous fungi (mold) to reduce solid waste (feces) while converting it into a consumable, high protein food product. Feces represent an untapped resource. Filamentous fungi are natural decomposers with the ability to use this resource. Many filamentous fungi are safe to eat. We examined growth in order to determine the conditions which maximized the rate of conversion of solid waste into fungal biomass. For this pilot, we compared the effect of different lengths of incubation, different methods of aeration, and different available surface area. The initial study resulted in rates of conversion as high as 75% (3.75g of mold produced from 5g of solid waste). Fungal growth also appeared to reduce odor. Although initially proposed as a mechanism to deal with waste and food storage issues on long-term space missions, this project holds the potential to benefit waste processing in diverse situations including large livestock confinement operations and sewage treatment facilities. This work was supported by a grant from the Indiana Space Grant Consortium (INSGC)
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