3,876 research outputs found
Archeological Survey and Survey-Level Testing for the Proposed Juan Seguin Park Plaza Project, Harris County, Texas
J. K. Wagner and Company, Inc. was retained by Harris County Precinct 2 to provide archeological investigations and historic research for the proposed Juan Seguin Park Plaza Project. The project area is owned by Harris County, and the project will be financed with county funds. The project will consist of new construction to update and modify the existing park.
The proposed Juan Seguin Park Plaza Project area is located on the west side of Texas Highway 134 at the south Lynchburg Ferry landing in east Harris County, Texas, and is approximately two acres in size. As the investigation revealed, the entire project area was apparently buried to a height above surrounding grades of about six to eight feet by the addition of fill.
On September 4, 2010, J. K. Wagner and Company, Inc. conducted an archeological survey with backhoe trenching under the auspices of Texas Antiquities Permit Number 5745. The entire site was subjected to pedestrian survey, and six backhoe trenches were excavated to six to eight feet below existing grade. All backhoe trenches revealed multiple layers of modern fill that included materials such as concrete rubble, asphalt chunks, metal and plastic water pipe segments, and other debris. No evidence of pre-1870s artifacts or features of the Historic period, or of prehistoric or aboriginal sites was encountered. Nothing was collected or curated.
Based on those findings, J. K. Wagner and Company, Inc. believes that the area investigated likely contains no cultural evidence or resources worthy of further investigation or eligible for land marking at the local, state, or national levels. Further, J. K. Wagner and Company, Inc. recommends that the proposed project should proceed without further cultural resource investigation. However, if areas outside of those subjected to backhoe trenching in the initial investigation will be impacted deeper than six feet below current grade, those areas should be examined prior to impact
Optical Continuum and Emission-Line Variability of Seyfert 1 Galaxies
We present the light curves obtained during an eight-year program of optical
spectroscopic monitoring of nine Seyfert 1 galaxies: 3C 120, Akn 120, Mrk 79,
Mrk 110, Mrk 335, Mrk 509, Mrk 590, Mrk 704, and Mrk 817. All objects show
significant variability in both the continuum and emission-line fluxes. We use
cross-correlation analysis to derive the sizes of the broad Hbeta-emitting
regions based on emission-line time delays, or lags. We successfully measure
time delays for eight of the nine sources, and find values ranging from about
two weeks to a little over two months. Combining the measured lags and widths
of the variable parts of the emission lines allows us to make virial mass
estimates for the active nucleus in each galaxy. The virial masses are in the
range 10^{7-8} solar masses.Comment: 24 pages, 16 figures. Accepted for publication in Ap
A Rare Presentation of Drug-induced Liver Injury with Fluticasone and Vilanterol Inhaler Use
Drug-induced liver injury (DILI) is a rare and potentially lethal condition associated with the use of many commonly-used medications, including inhaled fluticasone-vilanterol. Therefore, a careful review of medications should always be obtained in the setting of acute onset hepatic dysfunction. We present the first reported case of idiosyncratic drug-induced liver injury associated with the use of this medication
A Photometric and Spectroscopic Study of the Cataclysmic Variable SX Leonis Minoris in Quiescence and Superoutburst
We present CCD imaging, CCD photometry on long and short timescales, and time-resolved spectroscopy of SX LMi, a new SU Ursae Majoris type dwarf nova. The quiescent optical spectrum shows broad double-peaked Balmer, He I, and He II emission lines, similar to other quiescent dwarf novae. Absorption lines from a late-type secondary are not detected. Time-resolved spectra obtained in quiescence reveal radial velocity variations of the Balmer emission lines on a period of 0.06717 ± 0.00011 days, or 96.72 ± 0.16 minutes, with only a slight possibility of a daily cycle-count error. Optical photometry obtained between 1987 and 1991 shows flickering with a peak-to-peak amplitude of 0.18 mag. The binary orbital period can sometimes be seen in the photometric record. Long-term photometric monitoring by Indiana University\u27s robotic telescope RoboScope for a 3 year period between 1992 October and 1995 June shows seven well-defined outbursts and marginally detects a few others. The outburst interval varies between 34 and 64 days. During the 1994 December outburst, optical photometric observations show that SX LMi exhibited superhumps with a period of 0.06893 ± 0.00012 days, which is 2.6% ± 0.2% longer than the orbital period, as expected for a normal SU UMa star at this period. Spectra obtained during superoutburst show dramatic variations in the emission-line profiles on timescales of 10 minutes. Profile fits indicate that underlying absorption contributes to the shape of the Balmer emission-line profiles during superoutburst as in other dwarf novae in outburst or superoutburst. Direct images in good seeing show a ~19 mag companion star 195 from SX LMi
Neurochemical enhancement of conscious error awareness
How the brain monitors ongoing behavior for performance errors is a central question of cognitive neuroscience. Diminished awareness of performance errors limits the extent to which humans engage in corrective behavior and has been linked to loss of insight in a number of psychiatric syndromes (e.g., attention deficit hyperactivity disorder, drug addiction). These conditions share alterations in monoamine signaling that may influence the neural mechanisms underlying error processing, but our understanding of the neurochemical drivers of these processes is limited.Weconducted a randomized, double-blind, placebo-controlled, cross-over design of the influence of methylphenidate, atomoxetine, and citalopram on error awareness in 27 healthy participants. The error awareness task, a go/no-go response inhibition paradigm, was administered to assess the influence of monoaminergic agents on performance errors during fMRI data acquisition. A single dose of methylphenidate, but not atomoxetine or citalopram, significantly improved the ability of healthy volunteers to consciously detect performance errors. Furthermore, this behavioral effect was associated with a strengthening of activation differences in the dorsal anterior cingulate cortex and inferior parietal lobe during the methylphenidate condition for errors made with versus without awareness. Our results have implications for the understanding of the neurochemical underpinnings of performance monitoring and for the pharmacological treatment of a range of disparate clinical conditions that are marked by poor awareness of errors
Radio Variability of Radio Quiet and Radio Loud Quasars
The majority of quasars are weak in their radio emission, with flux densities
comparable to those in the optical, and energies far lower. A small fraction,
about 10%, are hundreds to thousands of times stronger in the radio.
Conventional wisdom holds that there are two classes of quasars, the radio
quiets and radio louds, with a deficit of sources having intermediate power.
Are there really two separate populations, and if so, is the physics of the
radio emission fundamentally different between them? This paper addresses the
second question, through a study of radio variability across the full range of
radio power, from quiet to loud. The basic findings are that the root mean
square amplitude of variability is independent of radio luminosity or
radio-to-optical flux density ratio, and that fractionally large variations can
occur on timescales of months or less in both radio quiet and radio loud
quasars. Combining this with similarities in other indicators, such as radio
spectral index and the presence of VLBI-scale components, leads to the
suggestion that the physics of radio emission in the inner regions of all
quasars is essentially the same, involving a compact, partially opaque core
together with a beamed jet.Comment: 32 pages, 9 figures. Astrophysical Journal, in pres
Impact of population growth and population ethics on climate change mitigation policy
Future population growth is uncertain and matters for climate policy: higher growth entails more emissions and means more people will be vulnerable to climate-related impacts. We show that how future population is valued importantly determines mitigation decisions. Using the Dynamic Integrated Climate-Economy model, we explore two approaches to valuing population: a discounted version of total utilitarianism (TU), which considers total wellbeing and is standard in social cost of carbon dioxide (SCC) models, and of average utilitarianism (AU), which ignores population size and sums only each time period’s discounted average wellbeing. Under both approaches, as population increases the SCC increases, but optimal peak temperature decreases. The effect is larger under TU, because it responds to the fact that a larger population means climate change hurts more people: for example, in 2025, assuming the United Nations (UN)-high rather than UN-low population scenario entails an increase in the SCC of 85% under TU vs. 5% under AU. The difference in the SCC between the two population scenarios under TU is comparable to commonly debated decisions regarding time discounting. Additionally, we estimate the avoided mitigation costs implied by plausible reductions in population growth, finding that large near-term savings ($billions annually) occur under TU; savings under AU emerge in the more distant future. These savings are larger than spending shortfalls for human development policies that may lower fertility. Finally, we show that whether lowering population growth entails overall improvements in wellbeing—rather than merely cost savings—again depends on the ethical approach to valuing population
Impact of Controlling the Site Distribution of Al Atoms on Catalytic Properties in Ferrierite-Type Zeolites
Zeolites with the ferrierite (FER) topology are synthesized using a combination of tetramethylammonium
(TMA) cations with differently sized cyclic amines (pyrrolidine (Pyr), hexamethyleneimine (HMI), and 1,4-
diazabicyclo[2.2.2]octane (DAB)). Using these organic structure-directing agents (SDAs), low Si/Al ratios
and concentrated synthesis mixtures favor the crystallization of FER materials. Increasing the size of the
cyclic amine or decreasing the aluminum content leads to the crystallization of other phases or the creation
of excessive amounts of connectivity defects. TMA cations play a decisive role in the synthesis of the FER
materials, and their presence allows the use of HMI to synthesize FER. Proton MAS NMR is used to quantify
the accessibility of pyridine to acid sites in these FER samples, where it is found that the FER + HMI + TMA
sample contains only 27% acid sites in the 8-MR channels, whereas FER + Pyr and FER + Pyr + TMA
contain 89% and 84%, respectively. The constraint index (CI) test and the carbonylation of dimethyl ether
(DME) with carbon monoxide are used as probe reactions to evaluate how changes in the aluminum distribution
in these FER samples affect their catalytic behavior. Results show that the use of Pyr as an SDA results in
the selective population of acid sites in the 8-MR channels, whereas the use of HMI generates FER zeolites
with an increased concentration of acid sites in the 10-MR channels
A photometric and spectroscopic study of the cataclysmic variable SX Leonis Minoris in quiescence and superoutburst
We present CCD imaging, CCD photometry on long and short timescales, and time-resolved spectroscopy of SX LMi, a new SU Ursae Majoris type dwarf nova. The quiescent optical spectrum shows broad double-peaked Balmer, He I, and He II emission lines, similar to other quiescent dwarf novae. Absorption lines from a late-type secondary are not detected. Time-resolved spectra obtained in quiescence reveal radial velocity variations of the Balmer emission lines on a period of 0.06717 +/- 0.00011 days, or 96.72 +/- 0.16 minutes, with only a slight possibility of a daily cycle-count error. Optical photometry obtained between 1987 and 1991 shows flickering with a peak-to-peak amplitude of 0.18 mag. The binary orbital period can sometimes be seen in the photometric record. Long-term photometric monitoring for a three-year period between 1992 October and 1995 June shows seven well-defined outbursts and marginally detects a few others. The outburst interval varies between 34 and 64 days. During the 1994 December outburst, optical photometric observations show that SX LMi exhibited superhumps with a period of 0.06893 +/- 0.00012 days, which is 2.6 percent +/- 0.2 percent longer than the orbital period, as expected for a normal SU UMa star at this period. Spectra obtained during superoutburst show dramatic variations in the emission-line profiles on timescales of 10 minutes. Profile fits indicate that underlying absorption contributes to the shape of the
Balmer emission-line profiles during superoutburst as in other dwarf novae in outburst or superoutburst.
Direct images in good seeing show a ~D19 mag companion star from SX LMi
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