4,698 research outputs found
A Transition Plan for High School Special Education Students
The purpose of this project was to develop a transition plan that would facilitate the movement into the post-school setting for high school students with disabilities. Research on the factors that contribute to successful transition plans was examined. A four year transition plan for students with special needs was created that would detail specific requirements for each of the grades 9-12. These requirements would encompass vocational education/training and instruction, community experiences, life skills, functional vocational evaluation and assessment, interagency collaboration, parent involvement, and post-school education. The attainment of these requirements would be demonstrated by a cumulative portfolio
Antiherpes simplex virus type 2 activity of the antimicrobial peptide subtilosin
In the present study we evaluated the antiviral activity of subtilosin, a cyclical peptide isolated from Bacillus amyloliquefaciens, against herpes simplex virus type 2 (HSV-2) in cell cultures and we investigated subtilosin mode of action. We determined, using a virus yield inhibition assay, that non cytotoxic concentrations of subtilosin inhibit HSV-2 replication in Vero cell cultures. Subtilosin strongly inhibited extracellular and total virus production even when it was added at 8 h post-infection indicating that not only virus release but also viral particle formation is impeded by the antiviral peptide. Although viral glycoprotein gD level of expression is not affected by the bacteriocin, an altered pattern of gD intracellular localization was detected by immunofluorescence assay in subtilosin treated culture. On the other hand, at high concentrations subtilosin displays virucidal action.Fil: Quintana, Verónica Mara. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica. Laboratorio de Virología; ArgentinaFil: Torres, Nicolás. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica. Laboratorio de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Wachsman, Mónica B.. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica. Laboratorio de Virología; ArgentinaFil: Sinko, Patrick J.. State University of New Jersey; Estados UnidosFil: Castilla, Viviana. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica. Laboratorio de Virología; ArgentinaFil: Chikindas, Michael. State University of New Jersey; Estados Unido
Mitochondrial energetics of benthic and pelagic Antarctic teleosts.
Antarctic fauna are highly adapted to the frigid waters of the Southern Ocean. This study describes the in vitro temperature sensitivity of oxygen consumption rates measured in liver mitochondria from the pelagic notothenioid Pleuragramma antarcticum between 5 and 35 C. Oxygen fluxes were measured after the addition of millimolar levels of pyruvate, malate, succinate and glutamate (state II, LEAK) and saturating levels of ADP [state III, oxidative phosphorylation (OXPHOS)]. State III respiration significantly decreased above 18.7 C. A comparison of the oxidative capacities among P. antarcticum and other notothenioids showed significant differences in state III respiration, where benthic species exhibited about 50 % lower rates than P. antarcticum . In addition, state III respiration rates normalized per milligram of mitochondrial protein of P. antarcticum were up to eight times higher than state III rates reported in the literature for other notothenioids. The comparatively high respiration rates measured in this study may be explained by our approach, which engaged both complexes I and II under conditions of oxidative phosphorylation. State III rates of independently activated complexes I and II were found to range from 42 to 100 % of rates obtained when both complexes were activated simultaneously in the same species. The remarkable tolerance of P. antarcticum OXPHOS toward warmer temperatures was unexpected for an Antarctic stenotherm and may indicate that thermal sensitivity of their mitochondria is not the driving force behind their stenothermy
A Second Order Sliding Mode Controller with Predefined-Time Convergence
This paper presents the basis to design a well-suited control law which guarantees predefined-time convergence for a class of second-order systems. In contrast to the case of finite-time and fixed-time controllers, a predefined-time controller allows to set the bound of the convergence time, explicitly during the control design. Furthermore, in the case of no disturbance, the least upper bound of the convergence time can be predefined directly from the control definition. A Lyapunov-like characterization for predefined-time stability is performed. Numerical results are discussed to show the reliability of the proposed method.Consejo Nacional de Ciencia y Tecnologí
Utilizing Calibrated GPS Reflected Signals to Estimate Soil Reflectivity and Dielectric Constant: Results from SMEX02
Extensive reflected GPS data was collected using a GPS reflectometer installed on an HC130 aircraft during the Soil Moisture Experiment 2002 (SMEX02) near Ames, Iowa. At the same time, widespread surface truth data was acquired in the form of point soil moisture profiles, areal sampling of near-surface soil moisture, total green biomass and precipitation history, among others. Previously, there have been no reported efforts to calibrate reflected GPS data sets acquired over land. This paper reports the results of two approaches to calibration of the data that yield consistent results. It is shown that estimating the strength of the reflected signals by either (1) assuming an approximately specular surface reflection or (2) inferring the surface slope probability density and associated normalization constants give essentially the same results for the conditions encountered in SMEX02. The corrected data is converted to surface reflectivity and then to dielectric constant as a test of the calibration approaches. Utilizing the extensive in-situ soil moisture related data this paper also presents the results of comparing the GPS-inferred relative dielectric constant with the Wang-Schmugge model frequently used to relate volume moisture content to dielectric constant. It is shown that the calibrated GPS reflectivity estimates follow the expected dependence of permittivity with volume moisture, but with the following qualification: The soil moisture value governing the reflectivity appears to come from only the top 1-2 centimeters of soil, a result consistent with results found for other microwave techniques operating at L-band. Nevertheless, the experimentally derived dielectric constant is generally lower than predicted. Possible explanations are presented to explain this result
Mid-Infrared Spectroscopy of Uranus from the Spitzer Infrared Spectrometer: 2. Determination of the Mean Composition of the Upper Troposphere and Stratosphere
Mid-infrared spectral observations Uranus acquired with the Infrared
Spectrometer (IRS) on the Spitzer Space Telescope are used to determine the
abundances of C2H2, C2H6, CH3C2H, C4H2, CO2, and tentatively CH3 on Uranus at
the time of the 2007 equinox. For vertically uniform eddy diffusion
coefficients in the range 2200-2600 cm2 s-1, photochemical models that
reproduce the observed methane emission also predict C2H6 profiles that compare
well with emission in the 11.6-12.5 micron wavelength region, where the nu9
band of C2H6 is prominent. Our nominal model with a uniform eddy diffusion
coefficient Kzz = 2430 cm2 sec-1 and a CH4 tropopause mole fraction of 1.6x10-5
provides a good fit to other hydrocarbon emission features, such as those of
C2H2 and C4H2, but the model profile for CH3C2H must be scaled by a factor of
0.43, suggesting that improvements are needed in the chemical reaction
mechanism for C3Hx species. The nominal model is consistent with a CH3D/CH4
ratio of 3.0+-0.2x10-4. From the best-fit scaling of these photochemical-model
profiles, we derive column abundances above the 10-mbar level of 4.5+01.1/-0.8
x 10+19 molecule-cm-2 for CH4, 6.2 +- 1.0 x 10+16 molecule-cm-2 for C2H2 (with
a value 24% higher from a different longitudinal sampling), 3.1 +- 0.3 x 10+16
molecule-cm-2 for C2H6, 8.6 +- 2.6 x 10+13 molecule-cm-2 for CH3C2H, 1.8 +- 0.3
x 10+13 molecule-cm-2 for C4H2, and 1.7 +- 0.4 x 10+13 molecule-cm-2 for CO2 on
Uranus. Our results have implications with respect to the influx rate of
exogenic oxygen species and the production rate of stratospheric hazes on
Uranus, as well as the C4H2 vapor pressure over C4H2 ice at low temperatures
The Architecture of the GW Ori Young Triple Star System and Its Disk: Dynamical Masses, Mutual Inclinations, and Recurrent Eclipses
We present spatially and spectrally resolved Atacama Large
Millimeter/submillimeter Array (ALMA) observations of gas and dust orbiting the
pre-main sequence hierarchical triple star system GW Ori. A forward-modeling of
the CO and CO =2-1 transitions permits a measurement of
the total stellar mass in this system, , and the
circum-triple disk inclination, . Optical spectra spanning
a 35 year period were used to derive new radial velocities and, coupled with a
spectroscopic disentangling technique, revealed that the A and B components of
GW Ori form a double-lined spectroscopic binary with a day
period; a tertiary companion orbits that inner pair with a day
period. Combining the results from the ALMA data and the optical spectra with
three epochs of astrometry in the literature, we constrain the individual
stellar masses in the system (,
, ) and
find strong evidence that at least one (and likely both) stellar orbital planes
are misaligned with the disk plane by as much as . A -band light
curve spanning 30 years reveals several new 30 day eclipse events
0.1-0.7~mag in depth and a 0.2 mag sinusoidal oscillation that is clearly
phased with the AB-C orbital period. Taken together, these features suggest
that the A-B pair may be partially obscured by material in the inner disk as
the pair approaches apoastron in the hierarchical orbit. Lastly, we conclude
that stellar evolutionary models are consistent with our measurements of the
masses and basic photospheric properties if the GW Ori system is 1 Myr
old.Comment: 26 pages, 15 figures, accepted to Ap
Development of a Multiplex PCR Assay for Detection of Shiga Toxin-Producing Escherichia coli, Enterohemorrhagic E. coli, and Enteropathogenic E. coli Strains
Escherichia coli O157:H7 and other pathogenic E.coli strains are enteric pathogens associated with food safety threats and which remaina significant cause of morbidity and mortality worldwide. In the current study, we investigated whether enterohemorrhagic E. coli (EHEC), Shiga toxin-producing E. coli (STEC), and enteropathogenic E. coli (EPEC) strains can be rapidly and specifically differentiated with multiplex PCR (mPCR) utilizing selected biomarkers associated with each strains respective virulence genotype. Primers were designed to amplify multiple intimin (eae) and long polar fimbriae (lpfA) variants, the bundle forming pilus gene bfpA, and the Shiga toxin encoding genes stx1 and stx2. We demonstrated consistent amplification of genes specific to the prototype EHEC O157:H7 EDL933 (lpfA1-3, lpfA2-2, stx1, stx2, and eae-gama) and EPEC O127:H6 E2348/69 (eae-alfa, lpfA1-1, and bfpA) strains using the optimized mPCR protocol with purified genomic DNA (gDNA). A screen of gDNA from isolates in a diarrheagenic E. coli collection revealed that the mPCR assay was successful in predicting the correct pathotype of EPEC and EHEC clones grouped in the distinctive phyogenetic disease clusters EPEC1 and EHEC1, and was able to differentiate EHEC1 from EHEC2 clusters. The assay detection threshold was 2×104 CFU per PCR reaction for EHEC and EPEC. mPCR was also used to screen Argentinean clinical samples from hemolytic uremic syndrome and diarrheal patients, resultingin 91 % sensitivity and 84% specificity when compared to established molecular diagnostic procedures. In conclusion, our mPCR methodology permitted differentiation of EPEC, STEC and EHEC strains from other pathogenic E.coli; therefore, the assay becomes an additional tool for rapid diagnosis of these organisms.Instituto de Genética Veterinari
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