4,277 research outputs found

    Type-O\u27s

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    As technology becomes more heavily integrated in all aspects of modern day society, the ability to accurately and effectively interact with computers becomes increasingly important. This research will investigate a method to increase the memorization of key positions by treating the keyboard as a musical instrument, and not as a word processor. In typing games, such as JumpStart Typing, the user processes simple words generated from a prepared list. This method of memorization solidifies word patterns, but not the positions of the keys. These words consist of prefixes, roots, and suffixes that are used to generate other words; this is not how a musician learns his/her instrument. A musician does not memorize musical phrases that are more likely to appear in future songs he/she may encounter. A musician learns to play his/her instrument, and read sheet music simultaneously, by learning the positions of individual notes. Type-O’s is constructed in Unity3D using the C# programming language. Unity3D is a virtual game developing environment with libraries of game object elements which fulfill basic game developing mechanics, such as physics components and a Cartesian coordinate system. This expedites the production of a three-dimensional computer game, which can then be exported to a number of professional platforms. Because of its privacy and explicit variable declaration requirements, which add to the readability of the scripts, C# is the preferred language by 80% in the Unity3D community. Type-O’s uses a randomized layout to prevent a memorization of the game objects’ positions. As a ball traverses the field bumpers need to be activated by pressing their appropriate key to keep the ball in play. This fast paced environment and random events demand constant attention to the monitor, and not the keyboard and the game mechanics teach typing as a musical instrument

    Rapid variability at very high energies in Mrk 501

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    A major flaring state of the BL Lac object Mrk 501 was observed by the High Energy Stereoscopic System (H.E.S.S.) in June, 2014. Flux levels higher than one Crab unit were recorded and rapid variability at very high energies (\sim2-20 TeV) was revealed. The high statistics afforded by the flares allowed us to probe the presence of minutes timescale variability and study its statistical characteristics exclusively at TeV energies owing to the high energy threshold of approximately 2 TeV. Doubling times of a few minutes are estimated for fluxes greater than 2 TeV. Statistical tests on the light curves show interesting temporal structure in the variations including deviations from a normal flux distribution similar to those found in the PKS 2155-304 flare of July 2006, at nearly an order of magnitude higher threshold energy. Rapid variations at such high energies put strong constraints on the physical mechanisms in the blazar jet.Comment: In Proceedings of the 34th International Cosmic Ray Conference (ICRC2015), The Hague, The Netherland

    A Sustainable Prototype for Renewable Energy: Optimized Prime-power Generator Solar Array Replacement

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    Remote locations such as disaster relief camps, isolated arctic communities, and military forward operating bases are disconnected from traditional power grids forcing them to rely on diesel generators with a total installed capacity of 10,000 MW worldwide. The generators require a constant resupply of fuel, resulting in increased operating costs, negative environmental impacts, and challenging fuel logistics. To enhance remote site sustainability, planners can develop stand-alone photovoltaic-battery systems to replace existing prime power generators. This paper presents the development of a novel cost-performance model capable of optimizing solar array and Li-ion battery storage size by generating tradeoffs between minimizing initial system cost and maximizing power reliability. A case study for the replacement of an 800 kW generator, the US Air Force’s standard for prime power at deployed locations, was analyzed to demonstrate the model and its capabilities. A MATLAB model, simulating one year of solar data, was used to generate an optimized solution to minimize initial cost while providing over 99% reliability. Replacing a single diesel generator would result in a savings of 1.9 million liters of fuel, eliminating 100 fuel tanker truck deliveries annually. The distinctive capabilities of this model enable designers to enhance environmental, economic, and operational sustainability of remote locations by creating energy self-sufficient sites, which can operate indefinitely without the need for resupply

    Development of a Linear-Source, Atmospheric-Pressure RF Glow Discharge Plasma

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    A linear-source, atmospheric-pressure RF glow discharge plasma has been designed, fabricated, and analyzed. The RIT atmospheric-pressure plasma (RITAPP) consists of two parallel-plate electrodes separated by a 1.2 mm gap. Helium is flown through the gap, exiting the slit and impinging a substrate. 13.56 MHz RF power is applied to one electrode, resulting in a non-thermal plasma with a gas temperature (Tg) between 50 and 150 °C. Optical emission spectroscopy was used to determine spectral radiation in the UV-Vis region of helium and helium/oxygen plasmas. Singlet and triplet helium emissions as well as numerous 0, H, and OH peaks are observed. Surface treatment of bare 2” (100) p-type silicon wafers was performed by short exposure to a He/O2 plasma exposure increased surface energy, creating a hydrophilic surface. 20-minute exposures of bare and RCA-cleaned silicon substrates to a He/O2 plasma were analyzed using ellipsometry and mercury probe C-V measurements. Optical thickness was determined to be 3.4 nm while C-V measurements revealed that both the plasma-grown oxide and the chemical oxides exhibited enhanced dielectric properties following treatment. Work is ongoing to expand upon oxidation experiments as well as I-V diagnostics of the plasma. In addition, investigation of low-temperature carbon nanotube growth is underway

    Binary-state speciation and extinction method is conditionally robust to realistic violations of its assumptions

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    Phylogenetic comparative methods allow us to test evolutionary hypotheses without the benefit of an extensive fossil record. These methods, however, make simplifying assumptions, among them that clades are always increasing or stable in diversity, an assumption we know to be false. This study simulates hypothetical clades to test whether the Binary State Speciation and Extinction (BiSSE) method can be used to correctly detect relative differences in diversification rate between ancestral and derived character states even as net diversification rates are declining overall. We simulate clades with declining but positive diversification rates, as well those in which speciation rates decline below extinction rates so that they are losing richness for part of their history. We run these analyses both with simulated symmetric and asymmetric speciation rates to test whether BiSSE can be used to detect them correctly. For simulations with a neutral character, the fit for a BiSSE model with a neutral character is better than alternative models so long as net diversification rates remain positive. Once net diversification rates become negative, the BiSSE model with the greatest likelihood often has a non-neutral character, even though there is no such character in the simulation. BiSSE’s usefulness in detecting real asymmetry in speciation rates improves with clade age, even well after net diversification rates have become negative. BiSSE is most useful in analyzing clades of intermediate age, before they have reached peak diversity and gone into decline. After this point, users of BiSSE risk incorrectly inferring differential evolutionary rates when none exist. Fortunately, most studies using BiSSE and similar models focus on rapid, recent diversifications, and are less likely to encounter the biases BiSSE models are subject to for older clades. For extant groups that were once more diverse than now, however, caution should be taken in inferring past diversification patterns without fossil data

    Epitope mapping of sialyl Lewisx bound to E-selectin using saturation transfer difference NMR experiments

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    A complex between sialyl Lewisx (α-D-Neu5Ac-[2→3]- β-D-Gal-[1→4]-[α-L-Fuc-(1→3)]-β-D-GlcNAc-O-[CH2]8 COOMe) and E-selectin was studied using saturation transfer difference (STD) nuclear magnetic resonance (NMR) experiments. These experiments allow the identification of the binding epitope of a ligand at atomic resolution. A semiquantitative analysis of STD total correlation spectroscopy spectra provides clear evidence that the galactose residue receives the largest saturation transfer. The protons H4 and H6 of the galactose residue are in especially close contact to the amino acids of the E-selectin binding pocket. The fucose residue also receives a significant saturation transfer. The GlcNAc and Neu5Ac residues, with the exception of H3 and H3′ of Neu5Ac, were found to interact weakly with the protein surface. These findings are in excellent agreement with a recently published X-ray structure and with the earlier findings from syntheses and activity assays. To further characterize the binding pocket of E-selectin, an inhibitory peptide, Ac-TWDQLWDLMK-CONH2, was synthesized and the binding to E-selectin studied utilizing transfer nuclear Overhauser effect spectroscopy (trNOESY) experiments. Finally, competitive trNOESY experiments were performed, showing that the synthetic peptide is a competitive inhibitor of sialyl Lewis

    Impacts of Co-Solvent Flushing on Microbial Populations Capable of Degrading Trichloroethylene

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    With increased application of co-solvent flushing technologies for removal of nonaqueous phase liquids from groundwater aquifers, concern over the effects of the solvent on native microorganisms and their ability to degrade residual contaminant has also arisen. This study assessed the impact of ethanol flushing on the numbers and activity potentials of trichloroethylene (TCE)-degrading microbial populations present in aquifer soils taken immediately after and 2 years after ethanol flushing of a former dry cleaners site. Polymerase chain reaction analysis revealed soluble methane monooxygenase genes in methanotrophic enrichments, and 16S rRNA analysis identified Methylocystis parvus with 98% similarity, further indicating the presence of a type II methanotroph. Dissimilatory sulfite reductase genes in sulfate-reducing enrichments prepared were also observed. Ethanol flushing was simulated in columns packed with uncontaminated soils from the dry cleaners site that were dosed with TCE at concentrations observed in the field; after flushing, the columns were subjected to a continuous flow of 500 pore volumes of groundwater per week. Total acridine orange direct cell counts of the flushed and nonflushed soils decreased over the 15-week testing period, but after 5 weeks, the flushed soils maintained higher cell counts than the nonflushed soils. Inhibition of methanogenesis by sulfate reduction was observed in all column soils, as was increasing removal of total methane by soils incubated under methanotrophic conditions. These results showed that impacts of ethanol were not as severe as anticipated and imply that ethanol may mitigate the toxicity of TCE to the microorganisms

    Lrg1 Regulates β (1, 3)-Glucan Masking in Candida albicans through the Cek1 MAP Kinase Pathway

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    Candida albicans is among the most prevalent opportunistic human fungal pathogens. The ability to mask the immunogenic polysaccharide β (1,3)-glucan from immune detection via a layer of mannosylated proteins is a key virulence factor of C. albicans. We previously reported that hyperactivation of the Cek1 mitogen-activated protein (MAP) kinase pathway promotes β (1,3)-glucan exposure. In this communication, we report a novel upstream regulator of Cek1 activation and characterize the impact of Cek1 activity on fungal virulence. Lrg1 encodes a GTPase-activating protein (GAP) that has been suggested to inhibit the GTPase Rho1. We found that disruption of LRG1 causes Cek1 hyperactivation and β (1,3)-glucan unmasking. However, when GTPase activation was measured for a panel of GTPases, the lrg1ΔΔ mutant exhibited increased activation of Cdc42 and Ras1 but not Rho1 or Rac1. Unmasking and Cek1 activation in the lrg1ΔΔ mutant can be blocked by inhibition of the Ste11 MAP kinase kinase kinase (MAPKKK), indicating that the lrg1ΔΔ mutant acts through the canonical Cek1 MAP kinase cascade. In order to determine how Cek1 hyperactivation specifically impacts virulence, a doxycycline-repressible hyperactive STE11ΔN467 allele was expressed in C. albicans. In the absence of doxycycline, this allele overexpressed STE11ΔN467, which induced production of proinflammatory tumor necrosis factor alpha (TNF-α) from murine macrophages. This in vitrophenotype correlates with decreased colonization and virulence in a mouse model of systemic infection. The mechanism by which Ste11ΔN467 causes unmasking was explored with RNA sequencing (RNA-Seq) analysis. Overexpression of Ste11ΔN467 caused upregulation of the Cph1 transcription factor and of a group of cell wall-modifying proteins which are predicted to impact cell wall architecture

    Use of Two Self-referral Reminders and a Theory-Based Leaflet to Increase the Uptake of Flexible Sigmoidoscopy in the English Bowel Scope Screening Program: Results From a Randomized Controlled Trial in London

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    Background We previously initiated a randomized controlled trial to test the effectiveness of two self-referral reminders and a theory-based leaflet (sent 12 and 24 months after the initial invitation) to increase participation within the English Bowel Scope Screening program. Purpose This study reports the results following the second reminder. Methods Men and women included in the initial sample (n = 1,383) were re-assessed for eligibility 24 months after their invitation (12 months after the first reminder) and excluded if they had attended screening, moved away, or died. Eligible adults received the same treatment they were allocated 12 months previous, that is, no reminder (“control”), or a self-referral reminder with either the standard information booklet (“Reminder and Standard Information Booklet”) or theory-based leaflet designed using the Behavior Change Wheel (“Reminder and Theory-Based Leaflet”). The primary outcome was the proportion screened within each group 12 weeks after the second reminder. Results In total, 1,218 (88.1%) individuals were eligible. Additional uptake following the second reminder was 0.4% (2/460), 4.8% (19/399), and 7.9% (29/366) in the control, Reminder and Standard Information Booklet, and Reminder and Theory-Based Leaflet groups, respectively. When combined with the first reminder, the overall uptake for each group was 0.7% (3/461), 14.5% (67/461), and 21.5% (99/461). Overall uptake was significantly higher in the Reminder and Standard Information Booklet and Reminder and Theory-Based Leaflet groups than in the control (odds ratio [OR] = 26.1, 95% confidence interval [CI] = 8.1–84.0, p < .001 and OR = 46.9, 95% CI = 14.7–149.9, p < .001, respectively), and significantly higher in the Reminder and Theory-Based Leaflet group than in the Reminder and Standard Information Booklet group (OR = 1.8, 95% CI = 1.3–2.6, p < .001). Conclusion A second reminder increased uptake among former nonparticipants. The added value of the theory-based leaflet highlights a potential benefit to reviewing the current information booklet. Trials Registry Number ISRCTN44293755
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