Increasing Reliability of a Small 2-Stroke Internal Combustion Engine for Dynamically Changing Attitudes

Remotely Piloted Aircraft (RPA) typically utilize commercial internal combustion engines (ICE) as their power sources. These engines are designed to run at sea level, but these aircraft are often pressed into service at higher altitudes where the performance characteristics deteriorate. A Brison 95cc two-stroke engine\u27s performance characteristics at altitude are investigated using a test facility that can measure these characteristics over a range of pressures and temperatures. With its stock carburetor at sea level static (SLS) conditions, the engine makes 5.5 peak horsepower (hp) and brake specific fuel consumption (BSFC) ranged from 1.2-4.0 lb/(hp-hr). At 10,000 feet conditions, the peak hp drops 40% while off peak hp conditions can see a drop of over 90%. In addition, the carburetor makes operating at high altitudes unreliable. To increase reliability, a throttle body fuel injection (TBI) system was installed on the engine in place of the carburetor. The fuel injection system matched carburetor peak power at SLS conditions while increasing power by as much as 90% at low RPM and high altitude operating conditions. BSFC is decreased to a consistent 1.0 to 1.2 lb/(hp-hr) across all operating conditions. Lastly, both reliability at high altitude and startup reliability are increased with the TBI system while eliminating the need for tuning by the end user

Sarcospan Regulates Cardiac Isoproterenol Response and Prevents Duchenne Muscular Dystrophy-Associated Cardiomyopathy.

BackgroundDuchenne muscular dystrophy is a fatal cardiac and skeletal muscle disease resulting from mutations in the dystrophin gene. We have previously demonstrated that a dystrophin-associated protein, sarcospan (SSPN), ameliorated Duchenne muscular dystrophy skeletal muscle degeneration by activating compensatory pathways that regulate muscle cell adhesion (laminin-binding) to the extracellular matrix. Conversely, loss of SSPN destabilized skeletal muscle adhesion, hampered muscle regeneration, and reduced force properties. Given the importance of SSPN to skeletal muscle, we investigated the consequences of SSPN ablation in cardiac muscle and determined whether overexpression of SSPN into mdx mice ameliorates cardiac disease symptoms associated with Duchenne muscular dystrophy cardiomyopathy.Methods and resultsSSPN-null mice exhibited cardiac enlargement, exacerbated cardiomyocyte hypertrophy, and increased fibrosis in response to β-adrenergic challenge (isoproterenol; 0.8 mg/day per 2 weeks). Biochemical analysis of SSPN-null cardiac muscle revealed reduced sarcolemma localization of many proteins with a known role in cardiomyopathy pathogenesis: dystrophin, the sarcoglycans (α-, δ-, and γ-subunits), and β1D integrin. Transgenic overexpression of SSPN in Duchenne muscular dystrophy mice (mdx(TG)) improved cardiomyofiber cell adhesion, sarcolemma integrity, cardiac functional parameters, as well as increased expression of compensatory transmembrane proteins that mediate attachment to the extracellular matrix.ConclusionsSSPN regulates sarcolemmal expression of laminin-binding complexes that are critical to cardiac muscle function and protects against transient and chronic injury, including inherited cardiomyopathy

Comparing methods of barometric efficiency characterisation for specific storage estimation

Groundwater responses to barometric pressure fluctuations are characterized using the concept of barometric efficiency (BE). For semiconfined and confined aquifers, BE values can be used to provide efficient, low-cost estimates of specific storage. This study compares, for the first time, eight existing methods of BE estimation. Comparisons were undertaken using data from the Peel region of Western Australia. Fourier analysis and regression deconvolution methods were used to estimate aquifer confinement status. The former approach was found to be robust and provided a quantitative basis for spatial comparisons of the degree of confinement. The latter approach was confounded by the presence of diurnal and/or semidiurnal signals. For wells at which semiconfined or confined responses were identified, frequency and time domain methods were used to estimate BE values. Most BE estimation methods were similarly confounded by diurnal and/or semidiurnal signals, with the exception of the Acworth et al. (2016) method. Specific storage values calculated from BE values were order-of-magnitude consistent with the results of four historical pumping tests. The methods implemented in this research provide efficient, low-cost alternatives to hydraulic testing for estimating aquifer confinement, as well as the BE and specific storage of semiconfined and confined aquifers. The frequency and duration of observations required by these methods are minimal; for example, typically requiring a minimum of four observations per day over a four month period. In some locations they may allow additional insights to be derived from existing groundwater hydrograph data

Conceptions of Learning and Teaching and Their Relation to Educational Variables During Teaching Second Language

Background:  People who choose to study a second language like English face an emotional charge that affects directly to the learning process. Regarding the writing production, learners create short compositions about specific topics with instructions based on grammatical structures. Once it is done, learners receive feedback on their work. However, some learners do not want to write any text because the teacher puts more attention to their mistakes rather than their successes. Without taking into account their needs, topics of interest or motivation for carrying out the exercise Contribution:  Therefore, it is set to identify the emotions that are generated by the corrections made to our learners’ written work. Method:  The research was carried on with university students aged between 18 and 25 years old who are attending classes at the center of university language classroom. This research during the April- August 2016 term. Results: It has been found that the emotions (positive and negative) play an important role or have a great impact that causes aversion towards language learning. Therefore, it is necessary that teachers provide adequate feedback for language learning. Conclusion:  Corrections generate aversion towards the learning process. Regarding the feedback students receive from their teachers, it generates emotional charge (positive and negative) which should be followe

Transmission electron microscopy structure and platinum-like temperature coefficient of resistance in a ruthenate-based thick film resistor with copper oxide

As an alternative to thin-film platinum temperature sensor elements, thick film resistor ones are of interest for circuits which can withstand a near-engine environment. From a pyrochlore paste (DuPont 5091D), a close match is obtained (after firing) to the positive temperature coefficient of resistance (TCR) of Pt. Within the glassy matrix during 850 °C850 °C firing, needle-like RuO2RuO2 grains grow by a mechanism consistent with periodic bond chain theory. The acicular growth habit is attributed to a Cu2OCu2O additive, which is assumed to oxidize upon firing. The needles provide direct paths for metallic conduction and a characteristic positive TCR to the thick film in spite of having a low RuO2RuO2 volume fraction. © 2000 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70506/2/JAPIAU-88-2-1124-1.pd

An Experimental Test of a Reward-Cost Formulation of Status Inconsistency

The authors develop a theory in which consistency of ranks on position and ability affect individual satisfaction and system stability. The mechanism is rewards associated with different patterns. For instance, when position is rewarded more than ability, a low ability individual with a high position will be satisfied; when position and ability are rewarded equally, then rank consistency will be most satisfactory

Observational evidence for the convective transport of dust over the central United States

Bulk aerosol composition and aerosol size distributions measured aboard the DC-8 aircraft during the Deep Convective Clouds and Chemistry Experiment mission in May/June 2012 were used to investigate the transport of mineral dust through nine storms encountered over Colorado and Oklahoma. Measurements made at low altitudes (\u3c5 km mean sea level (MSL)) in the storm inflow region were compared to those made in cirrus anvils (altitude \u3e 9 km MSL). Storm mean outflow Ca2+ mass concentrations and total coarse (1 µm \u3c diameter \u3c 5 µm) aerosol volume (Vc) were comparable to mean inflow values as demonstrated by average outflow/inflow ratios greater than 0.5. A positive relationship between Ca2+, Vc, ice water content, and large (diameter \u3e 50 µm) ice particle number concentrations was not evident; thus, the influence of ice shatter on these measurements was assumed small. Mean inflow aerosol number concentrations calculated over a diameter range (0.5 µm \u3c diameter \u3c 5.0 µm) relevant for proxy ice nuclei (NPIN) were ~15–300 times higher than ice particle concentrations for all storms. Ratios of predicted interstitial NPIN (calculated as the difference between inflow NPIN and ice particle concentrations) and inflow NPIN were consistent with those calculated for Ca2+ and Vc and indicated that on average less than 10% of the ingested NPIN were activated as ice nuclei during anvil formation. Deep convection may therefore represent an efficient transport mechanism for dust to the upper troposphere where these particles can function as ice nuclei cirrus forming in situ

A 1- to 5-MW, RCS-based, short-pulse spallation neutron source

Two accelerator configurations, the linac/compressor ring scheme and the linac/RCS scheme, are commonly used to provide the proton beam power for a short-pulse spallation neutron source. In one configuration, a full-power linac provides the beam power and a compressor ring shortens the pulse length from 1-ms down to 1 {micro}s. In the other, rapid cycling synchrotrons (RCSs) provide the beam power and also shorten the pulse length. A feasibility study of a staged approach to a 5-MW proton source utilizing RCS technology, allowing intermediate operation at 1 MW, was performed at ANL and is presented in this paper. This study is complementary to a study in progress at ORNL based on a linac and an accumulator ring. The 1-MW facility consists of a 400-MeV injector linac that delivers 0.5-mA time-averaged current, a synchrotron that accelerates the beam to 2 GeV at a 30-Hz rate, and two neutron-generating target stations. In the second phase, the 2-GeV beam is accelerated to 10 GeV by a larger RCS, increasing the facility beam power to 5 MW

Differential stress reaction of human colon cells to oleic-acid-stabilized and unstabilized ultrasmall iron oxide nanoparticles.

Therapeutic engineered nanoparticles (NPs), including ultrasmall superparamagnetic iron oxide (USPIO) NPs, may accumulate in the lower digestive tract following ingestion or injection. In order to evaluate the reaction of human colon cells to USPIO NPs, the effects of non-stabilized USPIO NPs (NS-USPIO NPs), oleic-acid-stabilized USPIO NPs (OA-USPIO NPs), and free oleic acid (OA) were compared in human HT29 and CaCo2 colon epithelial cancer cells. First the biophysical characteristics of NS-USPIO NPs and OA-USPIO NPs in water, in cell culture medium supplemented with fetal calf serum, and in cell culture medium preconditioned by HT29 and CaCo₂ cells were determined. Then, stress responses of the cells were evaluated following exposure to NS-USPIO NPs, OA-USPIO NPs, and free OA. No modification of the cytoskeletal actin network was observed. Cell response to stress, including markers of apoptosis and DNA repair, oxidative stress and degradative/autophagic stress, induction of heat shock protein, or lipid metabolism was determined in cells exposed to the two NPs. Induction of an autophagic response was observed in the two cell lines for both NPs but not free OA, while the other stress responses were cell- and NP-specific. The formation of lipid vacuoles/droplets was demonstrated in HT29 and CaCo₂ cells exposed to OA-USPIO NPs but not to NS-USPIO NPs, and to a much lower level in cells exposed to equimolar concentrations of free OA. Therefore, the induction of lipid vacuoles in colon cells exposed to OA utilized as a stabilizer for USPIO NPs is higly amplified compared to free OA, and is not observed in the absence of this lipid in NS-USPIO NPs