John R Johnson | North Carolina State University (original) (raw)
Papers by John R Johnson
We have derived a new broadband photometric metallicity calibration for stars on the lower main s... more We have derived a new broadband photometric metallicity calibration for stars on the lower main sequence. We find that M Dwarfs with that harbor giant planets are metal-rich compared to a volume-limited sample of low-mass stars in the Solar neighborhood, which is consistent with the planet-metallicity correlation observed around Sun-like stars. We are taking advantage of this correlation by conducting
AIP Conference Proceedings, 2009
We report the detection of a new large-mass planet orbiting around a K0 IV(V = 8.26) star which h... more We report the detection of a new large-mass planet orbiting around a K0 IV(V = 8.26) star which has a minimum mass Mpsin i = 10.70+/-0.50 MJup in a 696.0+/-2.6-day orbit. It was detected in precise radial velocity (RV) measurements from Subaru and Keck. The derived orbital parameters, based on a kappa2 which minimized by Downhill Simplex algorithm, suggests that
This program is for the research and development of advanced, solid-brush current collection syst... more This program is for the research and development of advanced, solid-brush current collection systems for application to innovative electrical machinery. The objectives of the program are to increase the useful lifetime, reduce the sliding contact losses and increase the operating current density of solid brushes operating to transfer current between moving portions of electrical machines. The advances in current collector
Nature, 2015
Most stars become white dwarfs after they have exhausted their nuclear fuel (the Sun will be one ... more Most stars become white dwarfs after they have exhausted their nuclear fuel (the Sun will be one such). Between one-quarter and one-half of white dwarfs have elements heavier than helium in their atmospheres, even though these elements ought to sink rapidly into the stellar interiors (unless they are occasionally replenished). The abundance ratios of heavy elements in the atmospheres of white dwarfs are similar to the ratios in rocky bodies in the Solar System. This fact, together with the existence of warm, dusty debris disks surrounding about four per cent of white dwarfs, suggests that rocky debris from the planetary systems of white-dwarf progenitors occasionally pollutes the atmospheres of the stars. The total accreted mass of this debris is sometimes comparable to the mass of large asteroids in the Solar System. However, rocky, disintegrating bodies around a white dwarf have not yet been observed. Here we report observations of a white dwarf--WD 1145+017--being transited by at least one, and probably several, disintegrating planetesimals, with periods ranging from 4.5 hours to 4.9 hours. The strongest transit signals occur every 4.5 hours and exhibit varying depths (blocking up to 40 per cent of the star's brightness) and asymmetric profiles, indicative of a small object with a cometary tail of dusty effluent material. The star has a dusty debris disk, and the star's spectrum shows prominent lines from heavy elements such as magnesium, aluminium, silicon, calcium, iron, and nickel. This system provides further evidence that the pollution of white dwarfs by heavy elements might originate from disrupted rocky bodies such as asteroids and minor planets.
Journal of natural products, Jan 16, 2015
Two new dibenz[b,f]oxepins, empetroxepins A and B (1 and 2), and seven known compounds (3-9) were... more Two new dibenz[b,f]oxepins, empetroxepins A and B (1 and 2), and seven known compounds (3-9) were isolated from an extract of the Canadian medicinal plant Empetrum nigrum that significantly inhibited the growth of Mycobacterium tuberculosis H37Ra. The structures of 1 and 2 were established through analysis of NMR and MS data. The antimycobacterial activity of the plant extract was attributed primarily to the presence of two chalcone derivatives (6 and 7) that exhibited selective antimycobacterial activity (IC50 values of 23.8 and 32.8 μM, respectively) in comparison to mammalian (HEK 293) cells (IC50 values of 109 and 249 μM, respectively).
Journal of the Optical Society of America, 1955
The Mie theory is used in the computation of several transmission cross sections for absorbing sp... more The Mie theory is used in the computation of several transmission cross sections for absorbing spheres. For each sphere a complex index of refraction is selected such that the cross section corresponds to that of a water sphere illuminated by infrared radiation of mean wavelength less than 14 microns. The real part of the index is a value between 1.14 < in < 1.42 and the imaginary part, the absorption index, lies between 0 < mk <0.40.
Proceedings. International Test Conference, 2002
The Astrophysical Journal, 2009
We show that the exoplanet HAT-P-7b has an extremely tilted orbit, with a true angle of at least ... more We show that the exoplanet HAT-P-7b has an extremely tilted orbit, with a true angle of at least 86 • with respect to its parent star's equatorial plane, and a strong possibility of retrograde motion. We also report evidence for an additional planet or companion star. The evidence for the unparalleled orbit and the third body is based on precise observations of the star's apparent radial velocity. The anomalous radial velocity due to rotation (the Rossiter-McLaughlin effect) was found to be a blueshift during the first half of the transit and a redshift during the second half, an inversion of the usual pattern, implying that the angle between the skyprojected orbital and stellar angular momentum vectors is 182. • 5 ± 9. • 4. The third body is implicated by excess radial-velocity variation of the host star over 2 yr. Some possible explanations for the tilted orbit are a close encounter with another planet, the Kozai effect, and resonant capture by an inward-migrating outer planet.
We report precise Doppler measurements of two stars, obtained at Lick Observatory as part of our ... more We report precise Doppler measurements of two stars, obtained at Lick Observatory as part of our search for planets orbiting intermediate-mass sub- giants. Periodic variations in the radial velocities of both stars reveal the presence of substellar orbital companions. These two stars are notably mas- sive with stellar masses of 1.80 M⊙ and 1.64 M⊙, respectively, indicating that they are
Journal of ethnopharmacology, Jan 25, 2015
Alnus incana, commonly known as the gray or speckled alder, is a medicinal plant used by some Can... more Alnus incana, commonly known as the gray or speckled alder, is a medicinal plant used by some Canadian First Nations to treat symptoms associated with tuberculosis. The aim of the study was to assess the anti-mycobacterial activity of an Alnus incana bark extract and to identify the active constituents of the extract. Methanolic extracts of the bark of A. incana were subjected to bioassay guided fractionation using Mycobacterium tuberculosis (H37Ra). The active constituents were identified by NMR and MS. Four pentacyclic lupane triterpenes were isolated and were identified as betulin, betulinic acid, betulone and lupenone. Betulin displayed a MIC of 12.5μg/mL and an IC50 of 2.4μg/mL against M. tuberculosis (H37Ra). Betulinic acid and betulone showed lower anti-mycobacterial activities with IC50 values of 84 and 57μg/mL respectively. Lupenone was inactive against M. tuberculosis (H37Ra). Betulin, betulinic acid and betulone were identified as the major anti-mycobacterial constituents...
SAE Technical Paper Series, 2008
A Cummins ISB 5.9 liter medium-duty engine with cooled EGR has been used to study an early extrus... more A Cummins ISB 5.9 liter medium-duty engine with cooled EGR has been used to study an early extrusion of an advanced ceramic uncatalyzed diesel particulate filter (DPF). Data for the advanced ceramic material (ACM) and an uncatalyzed cordierite filter of similar dimensions are ...
The Spine Journal, 2008
The Spine Journal, Volume 8, Issue 5, Pages 80S-81S, September 2008, Authors:Steven Glassman, MD;... more The Spine Journal, Volume 8, Issue 5, Pages 80S-81S, September 2008, Authors:Steven Glassman, MD; Leah Carreon, MD, MSc; Mladen Djurasovic, MD; Mitchell Campbell, MD; Rolando Puno, MD; John Johnson, MD; John Dimar, MD. Journal Home, ...
Emission Control Science and Technology, 2014
The investigation of the distribution of particulate matter (PM) inside a catalyzed particulate f... more The investigation of the distribution of particulate matter (PM) inside a catalyzed particulate filter (CPF) is studied in this work. The goal was to identify how loading, passive oxidation, active regeneration, and post loading conditions affect the PM distribution. The PM distribution was measured using an Advantest TAS7000 3D Imaging Analysis System, which nondestructively measures the PM distribution. A total of nine experiments were conducted, resulting in three loading scans, four passive oxidation scans, four active regeneration scans, and two post loading scans. The loading experiments were run with two different target PM loadings of 3 and 5 g/L. The passive oxidation experiments were run under two different engine conditions, and four different amounts of PM were oxidized. The active regeneration experiments were run at two target temperatures of 525 and 600°C, and four levels of PM were oxidized. One post loading experiment was completed after a passive oxidation, and one was completed after an active regeneration. The results show that the PM distribution after loading is similar to the model-predicted PM distribution, which is calculated using the wall flow velocity distribution. The amount of PM in the substrate affects the axial distribution uniformity. The amount of PM passively oxidized or actively regenerated affects the axial distribution uniformity as well. The effect of post loading is dependent on whether the PM was passively oxidized or actively regenerated. Passive oxidation Active regeneration O 2 -assisted PM oxidation Post loading PM loading that occurs after a passive oxidation or active regeneration EOC Engine operating condition
2002 IEEE International Conference on Communications. Conference Proceedings. ICC 2002 (Cat. No.02CH37333), 2002
Abstract The introduction of adaptive multi-rate (AMR) speech coders in wireless standards, such ... more Abstract The introduction of adaptive multi-rate (AMR) speech coders in wireless standards, such as GSM, imposes new challenges for forward error correction (FEC) design. Traditional FEC techniques of providing unequal error protection (UEP) may not maximize ...
The Astrophysical Journal, 2006
The unusual flux variations of the pre-main-sequence binary star KH 15D have been attributed to o... more The unusual flux variations of the pre-main-sequence binary star KH 15D have been attributed to occultations by a circumbinary disk. We test whether or not this theory is compatible with newly available data, including recent radial velocity measurements, CCD photometry over the past decade, and photographic photometry over the past 50 years. We find the model to be successful, after two refinements: a more realistic motion of the occulting feature, and a halo around each star that probably represents scattering by the disk. The occulting feature is exceptionally sharp-edged, raising the possibility that the dust in the disk has settled into a thin layer, and providing a tool for fine-scale mapping of the immediate environment of a T Tauri star. However, the window of opportunity is closing, as the currently visible star may be hidden at all orbital phases by as early as 2008. Subject headings: stars: pre-main-sequence-stars: individual (KH 15D)-circumstellar matter-open clusters and associations: individual (NGC 2264)
Journal of genetic counseling, 2002
The objective of this document is to provide health care professionals with recommendations for g... more The objective of this document is to provide health care professionals with recommendations for genetic counseling and testing of individuals with a suspected or confirmed diagnosis of Fabry disease, with a family history of Fabry disease, and those identified as female carriers of Fabry disease. These recommendations are the opinions of a multicenter working group of genetic counselors, medical geneticists, and other health professionals with expertise in Fabry disease counseling, as well as an individual with Fabry disease who is a founder of a Fabry disease patient advocacy group in the United States. The recommendations are U.S. Preventive Task Force Class III, and they are based on clinical experience, a review of pertinent English-language articles, and reports of expert committees. This document reviews the genetics of Fabry disease, the indications for genetic testing and interpretation of results, psychosocial considerations, and references for professional and patient reso...
The Spine Journal, 2003
been successfully extrapolated to the cervical spine. However, cervical fusion cages have receive... more been successfully extrapolated to the cervical spine. However, cervical fusion cages have received FDA approval only recently thus there is limited information on long-term outcomes. The current study prospectively examines long-term pain and function outcomes following cervical interbody fusion with cages. METHODS: This study cohort consists of 93 patients who underwent anterior discectomy and fusion with cervical interbody fusion cages (BAK/ C Interbody Fusion System) and were followed a minimum of 4 years postoperatively. Patients were diagnosed with discogenic radiculopathy at no more than 2 contiguous levels from C3 to C7. The cervical cage(s) was implanted according to the manufacturer's guide. Patients were instructed to wear a cervical collar for 6 weeks post-surgery. Demographics and surgical stressors were collected. Fusion was independently assessed and defined asϽ2 degrees of motion on flex/ext radiographs and no radiolucencies. For 2-level cases both levels had to meet these criteria to be considered fused. Neck and arm pain were assessed using 10 cm VAS scales. The SF-36 was administered at all time points. Patients' perception of surgery was rated on a 4-point scale. Patient work status was also determined. Outcome measures were collected preoperatively and 3, 6, 12 months post-operatively and then yearly following. The last follow up was a minimum of 4 years post surgery (mean: 4.4 yrs; max 6.25 yrs.).
The Astrophysical Journal, 2009
We present photometric and spectroscopic observations of the 2009 Feb. 2 transit of the exoplanet... more We present photometric and spectroscopic observations of the 2009 Feb. 2 transit of the exoplanet XO-3b. The new data show that the planetary orbital axis and stellar rotation axis are misaligned, as reported earlier by Hébrard and coworkers. We find the angle between the sky projections of the two axes to be 37.3 ± 3.7 deg, as compared to the previously reported value of 70 ± 15 deg. The significance of this discrepancy is unclear because there are indications of systematic effects. XO-3b is the first exoplanet known to have a highly inclined orbit relative to the equatorial plane of its parent star, and as such it may fulfill the predictions of some scenarios for the migration of massive planets into close-in orbits. We revisit the statistical analysis of spin-orbit alignment in hot-Jupiter systems. Assuming the stellar obliquities to be drawn from a single Rayleigh distribution, we find the mode of the distribution to be 13 +5 −2 deg. However, it remains the case that a model representing two different migration channels-in which some planets are drawn from a perfectly-aligned distribution and the rest are drawn from an isotropic distribution-is favored over a single Rayleigh distribution.
We have derived a new broadband photometric metallicity calibration for stars on the lower main s... more We have derived a new broadband photometric metallicity calibration for stars on the lower main sequence. We find that M Dwarfs with that harbor giant planets are metal-rich compared to a volume-limited sample of low-mass stars in the Solar neighborhood, which is consistent with the planet-metallicity correlation observed around Sun-like stars. We are taking advantage of this correlation by conducting
AIP Conference Proceedings, 2009
We report the detection of a new large-mass planet orbiting around a K0 IV(V = 8.26) star which h... more We report the detection of a new large-mass planet orbiting around a K0 IV(V = 8.26) star which has a minimum mass Mpsin i = 10.70+/-0.50 MJup in a 696.0+/-2.6-day orbit. It was detected in precise radial velocity (RV) measurements from Subaru and Keck. The derived orbital parameters, based on a kappa2 which minimized by Downhill Simplex algorithm, suggests that
This program is for the research and development of advanced, solid-brush current collection syst... more This program is for the research and development of advanced, solid-brush current collection systems for application to innovative electrical machinery. The objectives of the program are to increase the useful lifetime, reduce the sliding contact losses and increase the operating current density of solid brushes operating to transfer current between moving portions of electrical machines. The advances in current collector
Nature, 2015
Most stars become white dwarfs after they have exhausted their nuclear fuel (the Sun will be one ... more Most stars become white dwarfs after they have exhausted their nuclear fuel (the Sun will be one such). Between one-quarter and one-half of white dwarfs have elements heavier than helium in their atmospheres, even though these elements ought to sink rapidly into the stellar interiors (unless they are occasionally replenished). The abundance ratios of heavy elements in the atmospheres of white dwarfs are similar to the ratios in rocky bodies in the Solar System. This fact, together with the existence of warm, dusty debris disks surrounding about four per cent of white dwarfs, suggests that rocky debris from the planetary systems of white-dwarf progenitors occasionally pollutes the atmospheres of the stars. The total accreted mass of this debris is sometimes comparable to the mass of large asteroids in the Solar System. However, rocky, disintegrating bodies around a white dwarf have not yet been observed. Here we report observations of a white dwarf--WD 1145+017--being transited by at least one, and probably several, disintegrating planetesimals, with periods ranging from 4.5 hours to 4.9 hours. The strongest transit signals occur every 4.5 hours and exhibit varying depths (blocking up to 40 per cent of the star&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s brightness) and asymmetric profiles, indicative of a small object with a cometary tail of dusty effluent material. The star has a dusty debris disk, and the star&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s spectrum shows prominent lines from heavy elements such as magnesium, aluminium, silicon, calcium, iron, and nickel. This system provides further evidence that the pollution of white dwarfs by heavy elements might originate from disrupted rocky bodies such as asteroids and minor planets.
Journal of natural products, Jan 16, 2015
Two new dibenz[b,f]oxepins, empetroxepins A and B (1 and 2), and seven known compounds (3-9) were... more Two new dibenz[b,f]oxepins, empetroxepins A and B (1 and 2), and seven known compounds (3-9) were isolated from an extract of the Canadian medicinal plant Empetrum nigrum that significantly inhibited the growth of Mycobacterium tuberculosis H37Ra. The structures of 1 and 2 were established through analysis of NMR and MS data. The antimycobacterial activity of the plant extract was attributed primarily to the presence of two chalcone derivatives (6 and 7) that exhibited selective antimycobacterial activity (IC50 values of 23.8 and 32.8 μM, respectively) in comparison to mammalian (HEK 293) cells (IC50 values of 109 and 249 μM, respectively).
Journal of the Optical Society of America, 1955
The Mie theory is used in the computation of several transmission cross sections for absorbing sp... more The Mie theory is used in the computation of several transmission cross sections for absorbing spheres. For each sphere a complex index of refraction is selected such that the cross section corresponds to that of a water sphere illuminated by infrared radiation of mean wavelength less than 14 microns. The real part of the index is a value between 1.14 < in < 1.42 and the imaginary part, the absorption index, lies between 0 < mk <0.40.
Proceedings. International Test Conference, 2002
The Astrophysical Journal, 2009
We show that the exoplanet HAT-P-7b has an extremely tilted orbit, with a true angle of at least ... more We show that the exoplanet HAT-P-7b has an extremely tilted orbit, with a true angle of at least 86 • with respect to its parent star's equatorial plane, and a strong possibility of retrograde motion. We also report evidence for an additional planet or companion star. The evidence for the unparalleled orbit and the third body is based on precise observations of the star's apparent radial velocity. The anomalous radial velocity due to rotation (the Rossiter-McLaughlin effect) was found to be a blueshift during the first half of the transit and a redshift during the second half, an inversion of the usual pattern, implying that the angle between the skyprojected orbital and stellar angular momentum vectors is 182. • 5 ± 9. • 4. The third body is implicated by excess radial-velocity variation of the host star over 2 yr. Some possible explanations for the tilted orbit are a close encounter with another planet, the Kozai effect, and resonant capture by an inward-migrating outer planet.
We report precise Doppler measurements of two stars, obtained at Lick Observatory as part of our ... more We report precise Doppler measurements of two stars, obtained at Lick Observatory as part of our search for planets orbiting intermediate-mass sub- giants. Periodic variations in the radial velocities of both stars reveal the presence of substellar orbital companions. These two stars are notably mas- sive with stellar masses of 1.80 M⊙ and 1.64 M⊙, respectively, indicating that they are
Journal of ethnopharmacology, Jan 25, 2015
Alnus incana, commonly known as the gray or speckled alder, is a medicinal plant used by some Can... more Alnus incana, commonly known as the gray or speckled alder, is a medicinal plant used by some Canadian First Nations to treat symptoms associated with tuberculosis. The aim of the study was to assess the anti-mycobacterial activity of an Alnus incana bark extract and to identify the active constituents of the extract. Methanolic extracts of the bark of A. incana were subjected to bioassay guided fractionation using Mycobacterium tuberculosis (H37Ra). The active constituents were identified by NMR and MS. Four pentacyclic lupane triterpenes were isolated and were identified as betulin, betulinic acid, betulone and lupenone. Betulin displayed a MIC of 12.5μg/mL and an IC50 of 2.4μg/mL against M. tuberculosis (H37Ra). Betulinic acid and betulone showed lower anti-mycobacterial activities with IC50 values of 84 and 57μg/mL respectively. Lupenone was inactive against M. tuberculosis (H37Ra). Betulin, betulinic acid and betulone were identified as the major anti-mycobacterial constituents...
SAE Technical Paper Series, 2008
A Cummins ISB 5.9 liter medium-duty engine with cooled EGR has been used to study an early extrus... more A Cummins ISB 5.9 liter medium-duty engine with cooled EGR has been used to study an early extrusion of an advanced ceramic uncatalyzed diesel particulate filter (DPF). Data for the advanced ceramic material (ACM) and an uncatalyzed cordierite filter of similar dimensions are ...
The Spine Journal, 2008
The Spine Journal, Volume 8, Issue 5, Pages 80S-81S, September 2008, Authors:Steven Glassman, MD;... more The Spine Journal, Volume 8, Issue 5, Pages 80S-81S, September 2008, Authors:Steven Glassman, MD; Leah Carreon, MD, MSc; Mladen Djurasovic, MD; Mitchell Campbell, MD; Rolando Puno, MD; John Johnson, MD; John Dimar, MD. Journal Home, ...
Emission Control Science and Technology, 2014
The investigation of the distribution of particulate matter (PM) inside a catalyzed particulate f... more The investigation of the distribution of particulate matter (PM) inside a catalyzed particulate filter (CPF) is studied in this work. The goal was to identify how loading, passive oxidation, active regeneration, and post loading conditions affect the PM distribution. The PM distribution was measured using an Advantest TAS7000 3D Imaging Analysis System, which nondestructively measures the PM distribution. A total of nine experiments were conducted, resulting in three loading scans, four passive oxidation scans, four active regeneration scans, and two post loading scans. The loading experiments were run with two different target PM loadings of 3 and 5 g/L. The passive oxidation experiments were run under two different engine conditions, and four different amounts of PM were oxidized. The active regeneration experiments were run at two target temperatures of 525 and 600°C, and four levels of PM were oxidized. One post loading experiment was completed after a passive oxidation, and one was completed after an active regeneration. The results show that the PM distribution after loading is similar to the model-predicted PM distribution, which is calculated using the wall flow velocity distribution. The amount of PM in the substrate affects the axial distribution uniformity. The amount of PM passively oxidized or actively regenerated affects the axial distribution uniformity as well. The effect of post loading is dependent on whether the PM was passively oxidized or actively regenerated. Passive oxidation Active regeneration O 2 -assisted PM oxidation Post loading PM loading that occurs after a passive oxidation or active regeneration EOC Engine operating condition
2002 IEEE International Conference on Communications. Conference Proceedings. ICC 2002 (Cat. No.02CH37333), 2002
Abstract The introduction of adaptive multi-rate (AMR) speech coders in wireless standards, such ... more Abstract The introduction of adaptive multi-rate (AMR) speech coders in wireless standards, such as GSM, imposes new challenges for forward error correction (FEC) design. Traditional FEC techniques of providing unequal error protection (UEP) may not maximize ...
The Astrophysical Journal, 2006
The unusual flux variations of the pre-main-sequence binary star KH 15D have been attributed to o... more The unusual flux variations of the pre-main-sequence binary star KH 15D have been attributed to occultations by a circumbinary disk. We test whether or not this theory is compatible with newly available data, including recent radial velocity measurements, CCD photometry over the past decade, and photographic photometry over the past 50 years. We find the model to be successful, after two refinements: a more realistic motion of the occulting feature, and a halo around each star that probably represents scattering by the disk. The occulting feature is exceptionally sharp-edged, raising the possibility that the dust in the disk has settled into a thin layer, and providing a tool for fine-scale mapping of the immediate environment of a T Tauri star. However, the window of opportunity is closing, as the currently visible star may be hidden at all orbital phases by as early as 2008. Subject headings: stars: pre-main-sequence-stars: individual (KH 15D)-circumstellar matter-open clusters and associations: individual (NGC 2264)
Journal of genetic counseling, 2002
The objective of this document is to provide health care professionals with recommendations for g... more The objective of this document is to provide health care professionals with recommendations for genetic counseling and testing of individuals with a suspected or confirmed diagnosis of Fabry disease, with a family history of Fabry disease, and those identified as female carriers of Fabry disease. These recommendations are the opinions of a multicenter working group of genetic counselors, medical geneticists, and other health professionals with expertise in Fabry disease counseling, as well as an individual with Fabry disease who is a founder of a Fabry disease patient advocacy group in the United States. The recommendations are U.S. Preventive Task Force Class III, and they are based on clinical experience, a review of pertinent English-language articles, and reports of expert committees. This document reviews the genetics of Fabry disease, the indications for genetic testing and interpretation of results, psychosocial considerations, and references for professional and patient reso...
The Spine Journal, 2003
been successfully extrapolated to the cervical spine. However, cervical fusion cages have receive... more been successfully extrapolated to the cervical spine. However, cervical fusion cages have received FDA approval only recently thus there is limited information on long-term outcomes. The current study prospectively examines long-term pain and function outcomes following cervical interbody fusion with cages. METHODS: This study cohort consists of 93 patients who underwent anterior discectomy and fusion with cervical interbody fusion cages (BAK/ C Interbody Fusion System) and were followed a minimum of 4 years postoperatively. Patients were diagnosed with discogenic radiculopathy at no more than 2 contiguous levels from C3 to C7. The cervical cage(s) was implanted according to the manufacturer's guide. Patients were instructed to wear a cervical collar for 6 weeks post-surgery. Demographics and surgical stressors were collected. Fusion was independently assessed and defined asϽ2 degrees of motion on flex/ext radiographs and no radiolucencies. For 2-level cases both levels had to meet these criteria to be considered fused. Neck and arm pain were assessed using 10 cm VAS scales. The SF-36 was administered at all time points. Patients' perception of surgery was rated on a 4-point scale. Patient work status was also determined. Outcome measures were collected preoperatively and 3, 6, 12 months post-operatively and then yearly following. The last follow up was a minimum of 4 years post surgery (mean: 4.4 yrs; max 6.25 yrs.).
The Astrophysical Journal, 2009
We present photometric and spectroscopic observations of the 2009 Feb. 2 transit of the exoplanet... more We present photometric and spectroscopic observations of the 2009 Feb. 2 transit of the exoplanet XO-3b. The new data show that the planetary orbital axis and stellar rotation axis are misaligned, as reported earlier by Hébrard and coworkers. We find the angle between the sky projections of the two axes to be 37.3 ± 3.7 deg, as compared to the previously reported value of 70 ± 15 deg. The significance of this discrepancy is unclear because there are indications of systematic effects. XO-3b is the first exoplanet known to have a highly inclined orbit relative to the equatorial plane of its parent star, and as such it may fulfill the predictions of some scenarios for the migration of massive planets into close-in orbits. We revisit the statistical analysis of spin-orbit alignment in hot-Jupiter systems. Assuming the stellar obliquities to be drawn from a single Rayleigh distribution, we find the mode of the distribution to be 13 +5 −2 deg. However, it remains the case that a model representing two different migration channels-in which some planets are drawn from a perfectly-aligned distribution and the rest are drawn from an isotropic distribution-is favored over a single Rayleigh distribution.