Characterization of a Silicon Nitride Plasma Etch: Selectivities and Uniformity

A silicon nitride plasma etch process with good nitride-to-oxide selectivity has been developed at RIT. Two fluorine etchant gases, CF4 and SF6, were characterized for etch rate and selectivities, and the effects of oxygen and hydrogen loading determined. It was found that the $~b stoh provided a selectivity of 6:1 (with a nitride etch rate of about 700 A/minute) when no loading was applied. The 3:1 CF4:02 etch demonstrated a comparable nitride etch rate, but with a poorer selectivity (about 5:2). The uniformity of the Tegal 700 plasma etching system was determined to be the limiting factor during the etch

Some Kentucky clays, including kaolinic, plastic and fire clays: clays in several parts of Kentucky, with some account of sands, marls and limestones

The bulletin is preliminary in character and is offered now simply in order to meet the urgent calls for all information concerning our clays that is at present available. A more comprehensive report, in which not only the geology and distribution of our clays, but also their technological values, will be given, will follow in due course. Data for such a bulletin are being gathered as rapidly as circumstances will permit. Among the clays upon which more field work is required are some of those associated with the coals and Conglomerate Measures of the Eastern Coalfield; those in other Lower Carbon­iferous regions than are included in this bulletin; those on the western rim of the Ordovician (Lower Silurian), and in parts of the Western Coalfield; while those of the Jackson\u27s Purchase region are to be studied in greater detail. It is believed that another year of field work will yield results sufficient to develop the lines along which technological work may be most profit­ably carried

Antibodies to normal and Alzheimer human brain structures from non-immunised mice of various ages

AbstractSupernatants from mouse spleen hybridoma lines established without previous immunisation were screened immunohistochemically against cryostat sections of human temporal cortex and found to stain a variety of brain structures, including Alzheimer plaques and tangles. The age of the mice had no effect on antibody production

Unstable Layers in the Mesopause Region Observed with Na Lidar During the Turbulent Oxygen Mixing Experiment (TOMEX) Campaign

The Na wind/temperature lidar located at Starfire Optical Range near Albuquerque, New Mexico, provided real time measurements of wind, temperature, and Na density in the mesopause region during the TOMEX rocket campaign in October 2000. The state of the atmosphere in which the rocket was launched into was examined using the lidar measurements. Both convectively and dynamically unstable layers were observed at various times and altitudes during the night. The low convective stability region below 90 km was found to be associated with the diurnal tide. The unstable layers are the combined results of wave and tidal perturbations. Comparison with the thermosphere/ionosphere/mesopshere/electrodynamics general circulation model (TIMEGCM) simulation showed that the model can produce the general feature of the observed atmospheric structure (but with a much smaller diurnal amplitude in temperature), which likely leads to underestimate of instability and gravity wave effects

Unstable Layers in the Mesopause Region Observed with Na Lidar During the Turbulent Oxygen Mixing Experiment (TOMEX) Campaign

The Na wind/temperature lidar located at Starfire Optical Range near Albuquerque, New Mexico, provided real time measurements of wind, temperature, and Na density in the mesopause region during the TOMEX rocket campaign in October 2000. The state of the atmosphere in which the rocket was launched into was examined using the lidar measurements. Both convectively and dynamically unstable layers were observed at various times and altitudes during the night. The low convective stability region below 90 km was found to be associated with the diurnal tide. The unstable layers are the combined results of wave and tidal perturbations. Comparison with the thermosphere/ionosphere/mesopshere/electrodynamics general circulation model (TIMEGCM) simulation showed that the model can produce the general feature of the observed atmospheric structure (but with a much smaller diurnal amplitude in temperature), which likely leads to underestimate of instability and gravity wave effects

Tau PET and multimodal brain imaging in patients at risk for chronic traumatic encephalopathy.

ObjectiveTo characterize individual and group-level neuroimaging findings in patients at risk for Chronic Traumatic Encephalopathy (CTE).MethodsEleven male patients meeting criteria for Traumatic Encephalopathy Syndrome (TES, median age: 64) underwent neurologic evaluation, 3-Tesla MRI, and PET with [18F]-Flortaucipir (FTP, tau-PET) and [11C]-Pittsburgh compound B (PIB, amyloid-PET). Six patients underwent [18F]-Fluorodeoxyglucose-PET (FDG, glucose metabolism). We assessed imaging findings at the individual patient level, and in group-level comparisons with modality-specific groups of cognitively normal older adults (CN). Tau-PET findings in patients with TES were also compared to a matched group of patients with mild cognitive impairment or dementia due to Alzheimer's disease (AD).ResultsAll patients with TES sustained repetitive head injury participating in impact sports, ten in American football. Three patients met criteria for dementia and eight had mild cognitive impairment. Two patients were amyloid-PET positive and harbored the most severe MRI atrophy, FDG hypometabolism, and FTP-tau PET binding. Among the nine amyloid-negative patients, tau-PET showed either mildly elevated frontotemporal binding, a "dot-like" pattern, or no elevated binding. Medial temporal FTP was mildly elevated in a subset of amyloid-negative patients, but values were considerably lower than in AD. Voxelwise analyses revealed a convergence of imaging abnormalities (higher FTP binding, lower FDG, lower gray matter volumes) in frontotemporal areas in TES compared to controls.ConclusionsMildly elevated tau-PET binding was observed in a subset of amyloid-negative patients at risk for CTE, in a distribution consistent with CTE pathology stages III-IV. FTP-PET may be useful as a biomarker of tau pathology in CTE but is unlikely to be sensitive to early disease stages

Fall 1970

How Water Moves in the Soil by Walter H. Gardner (page 3) Editorial (9) Turf Bulletin\u27s Photo Quiz by Fred Cheney (9) Public Relations by Marlin Ball (10) Turf Bulletin\u27s Photo Quiz Answer (11) Climate in the \u2770\u27s by James E. Newman (12) Know Your Seed--Ideas about Seed Quality by A.S. Carter (15)Seed Prices and Handling by Dwight M. Brown (16) Factors influencing Effectiveness of Two Surfactants on Water Repellent Soils by M.A. Mustafa and J. Letey (21

Distribution and dynamics of nitrogen and microbial plankton in southern Lake Michigan during spring transition 1999–2000

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95655/1/jgrc9187.pd