Spectral Response of the Pulsationally-Induced Shocks in the Atmosphere of BW Vulpeculae

The star BW Vul excites an extremely strong radial pulsation that grows in its envelope and is responsible for visible shock features in the continuum flux and spectral line profiles emerging in the atmosphere At two phases separated by 0.8 cycles. Material propelled upwards in the atmosphere from the shock returns to the lower photosphere where it creates a second shock just before the start of the next cycle. We have obtained three nights of echelle data for this star over about 5 pulsation cycles (P = 0.201 days) in order to evaluate the effects of on a number of important lines in the spectrum, including the HeI 5875A and 6678A lines. These data were supplemented by archival high-dispersion IUE (UV) data from 1994. A comparison of profiles of the two HeI lines during the peak of the infall activity suggests that differences in the development of the blue wing at this time are due to heating and short-lived formations of an optically thin layer above the atmospheric region compressed by the infall. This discovery and the well-known decreases in equivalent widths of the CII 6578-83A doublet at the two shock phases, suggests that shock flattens the temperature gradient and produces heating in heating the upper atmosphere. Except for absorptions in the blue wings of the UV resonance lines, we find no evidence for sequential shock delays arriving at various regions of line formation of the photosphere (a "Van Hoof effect"). Phase lags cited by some former observers may be false indicators arising from varying degrees of desaturation of multiple lines, such as for the red HeI lines. In addition, an apparent lag in the equivalent width curve of lines arising from less excited atomic levels could instead be caused by post-shock cooling, followed by a rebound shock.Comment: 12 pages in Latex/MNRAS format, 9 eps-format figure

Contralateral inhibition of click- and chirp-evoked human compound action potentials

Cochlear outer hair cells (OHC) receive direct efferent feedback from the caudal auditory brainstem via the medial olivocochlear (MOC) bundle. This circuit provides the neural substrate for the MOC reflex, which inhibits cochlear amplifier gain and is believed to play a role in listening in noise and protection from acoustic overexposure. The human MOC reflex has been studied extensively using otoacoustic emissions (OAE) paradigms; however, these measurements are insensitive to subsequent “downstream” efferent effects on the neural ensembles that mediate hearing. In this experiment, click- and chirp-evoked auditory nerve compound action potential (CAP) amplitudes were measured electrocochleographically from the human eardrum without and with MOC reflex activation elicited by contralateral broadband noise. We hypothesized that the chirp would be a more optimal stimulus for measuring neural MOC effects because it synchronizes excitation along the entire length of the basilar membrane and thus evokes a more robust CAP than a click at low to moderate stimulus levels. Chirps produced larger CAPs than clicks at all stimulus intensities (50–80 dB ppeSPL). MOC reflex inhibition of CAPs was larger for chirps than clicks at low stimulus levels when quantified both in terms of amplitude reduction and effective attenuation. Effective attenuation was larger for chirp- and click-evoked CAPs than for click-evoked OAEs measured from the same subjects. Our results suggest that the chirp is an optimal stimulus for evoking CAPs at low stimulus intensities and for assessing MOC reflex effects on the auditory nerve. Further, our work supports previous findings that MOC reflex effects at the level of the auditory nerve are underestimated by measures of OAE inhibition

A Phenomenological Study of African-American Students\u27 Spiritual and Identity Development at Predominantly White Institutions

The purpose of this transcendental phenomenological study is to document the lived experiences of African American (AA) students attending predominantly White institutions (PWI’s). The importance of capturing these experiences is to better understand how PWIs are properly equipped to serve the needs of their AA students. This study describe how AA students are experiencing spiritual and identity development while they are enrolled at a PWI. The two guiding theories of this study are Fowler’s Faith Development Theory and Erikson’s Identity Development Theory. These guiding theories have been paired together to address students’ spiritual development during their emerging adulthood years. The primary research question that the study will address is: How do AA students describe their experiences of spiritual and identity development while attending PWIs? The sub-questions of the study are: How do AA students who attend PWIs describe their experiences with student support services? What experiences do AA students perceive as contributing factors to their identity while attending PWIs? This qualitative study will employ transcendental phenomenology as the primary methodology. The setting of the study will be PWIs located in the southeastern region of the United States. Three themes emerged: (1) Displacement, (2) Self-Reliance, and (3) Resiliency. This study helps provide possible solutions to the imbalance in the spiritual and identity development of AA students attending PWI

Intensive Cultural Resources Survey of the 6.6-acre Haden Road Tract, Cloverleaf, Harris County, Texas

Horizon Environmental Services, Inc. (Horizon) was selected by Berg-Oliver Associates, Inc. (Berg Oliver) on behalf of Harris County Water Control Improvement District (WCID) No. 36 to conduct a cultural resources inventory survey and assessment for the proposed development of a wastewater treatment facility on the approximately 2.6-hectare (6.6-acre) Haden Road tract in Cloverleaf, Harris County, Texas. The currently undeveloped tract is located southeast of the intersection of Interstate Highway (IH) 10 and Haden Road. An unnamed tributary of Greens Bayou bisects the tract east to west. Based on historic-age aerials and topographic maps, no known development has occurred on the 2.7-hectare (6.6-acre) tract. The proposed project is being sponsored by Harris County WCID No. 36. Funding is being provided through a community development block grant (CDBG) contributed by the Texas General Land Office (GLO). Because the proposed wastewater treatment facility is being sponsored by a public utility and subsidized by a political subdivision of the state of Texas, the project falls under the jurisdiction of the Antiquities Code of Texas (Natural Resources Code, Title 9, Chapter 191). At this time, no federal funding, licenses, or permits are required for the proposed undertaking. However, should any impacts occur to the unnamed tributary of Greens Bayou that flows through the proposed project area, permitting would be required by the US Army Corps of Engineers (USACE) under Section 404 of the Clean Water Act (CWA). In this case, any portions of the overall project area that fall under the federal permit would also fall under the jurisdiction of Section 106 of the National Historic Preservation Act (NHPA) of 1966, as amended. As the project represents a publicly sponsored undertaking with the potential to impact potentially significant cultural resources, the project sponsor was required to perform a cultural resources inventory and assessment of the project area. On July 26, 2017, Horizon staff archeologist Briana Nicole Smith, under the overall direction of Jeffrey D. Owens, Principal Investigator, performed an intensive cultural resources survey of the project area to locate any cultural resources that potentially would be impacted by the proposed undertaking. Horizon’s archeologist traversed the project area on foot and thoroughly inspected the modern ground surface for aboriginal and historic-age cultural resources. In addition to pedestrian walkover, the Texas State Minimum Archeological Survey Standards (TSMASS) require a minimum of 2 shovel tests per acre for tracts between 3.0 and 10.0 acres in size. As such, a minimum of 13 shovel tests would be required within the 2.7- hectare (6.6-acre) project area. Horizon excavated a total of 15 shovel tests, thereby exceeding the TSMASS for a project area of this size. The survey was conducted under Texas Antiquities Permit No. 8115. Shovel testing revealed heavily disturbed artificial deposits of mottled sandy clay and dense clay sediments overlying the native clayey fluviomarine soils at depths of 20.0 to 40.0 centimeters (7.8 to 15.7 inches) below surface. Shovel tests were placed along both banks of the unnamed tributary of Greens Bayou. Ground surface visibility was low to moderate due to dense, ankle- to knee-high wild grasses and weeds, which cover the majority of the project area. The southwestern portion of the tract had less vegetation, allowing for better visibility of the heavily disturbed ground surface. Modern trash was abundant throughout the project area, which appears to be actively used as a dump site, and several shovel tests contained modern trash within the upper 20.0 centimeters. (7.8 inches). The majority of modern trash appears to have been dumped within the tree line that follows the southern boundary of the project area. The northernmost portion of the project area is disturbed from the construction of multiple storm water manholes. Based on the results of the survey-level investigations documented in this report, no potentially significant cultural resources would be affected by the proposed undertaking. In accordance with 36 CFR 800.4, Horizon has made a reasonable and good-faith effort to identify historic properties within the project area. No cultural resources were identified that meet the criteria for designation as SALs according to 13 TAC 26. Horizon recommends a finding of “no historic properties affected,” and no further archeological work is recommended in connection with the proposed undertaking. However, human burials, both prehistoric and historic, are protected under the Texas Health and Safety Code. In the event that any human remains or burial objects are inadvertently discovered at any point during construction, use, or ongoing maintenance in the project area, even in previously surveyed areas, all work should cease immediately in the vicinity of the inadvertent discovery, and the Texas Historical Commission (THC) should be notified immediately

Intensive Cultural Resources Survey of the 55.4-acre Rosser Quarry Expansion, Scurry, Kaufman County, Texas

On August 23, 2017, Horizon Environmental Services, Inc. (Horizon) conducted a cultural resources inventory survey and assessment for the proposed 22.4-hectare (55.4-acre) Rosser Quarry expansion in Scurry, Kaufman County, Texas. The currently undeveloped tract is located west of Rosser, Texas, between the Trinity River, approximately 270.0 meters (885.8 feet) to the west, and the existing Rosser Quarry to the east. Three US Army Corps of Engineer (USACE) jurisdictional “Waters of the US” (WOUS) are present within the southeastern portion of the project area. These consisted of two ephemeral branches of an unnamed tributary of the Trinity River as well as one excavated pond feature. Although the proposed work area would be located on private property and would be privately funded, the proposed impacts to the three jurisdictional water features would require permitting by the USACE under Section 404 of the Clean Water Act (CWA). As this is a federal permit, the proposed construction activities within the USACE jurisdictional areas fall under the jurisdiction of Section 106 of the National Preservation Act (NHPA) of 1966, as amended. Lattimore Materials contracted with Horizon to conduct an intensive cultural resources survey of the proposed project area in compliance with the regulations of Section 106 of the NHPA. The purpose of the survey was to determine if any cultural resources were located within the project area, and, if so, to determine their eligibility for inclusion in the National Register of Historic Places (NRHP). Current USACE guidance calls for conducting cultural resources surveys on the banks and adjacent uplands of WOUSs, which are typically defined as a 100.0-meter (328.0-foot) buffer surrounding of the jurisdictional feature. Thus, for purposes of the current cultural resources survey, the Area of Potential Effect (APE) would be considered to extend 100.0 meters (328.0 feet) surrounding the edges of the three jurisdictional features in the southeastern corner of the overall project area. However, as the physiographic setting of the project area on the floodplain of the Trinity River suggested a high potential for previously undocumented cultural resources, Horizon conducted an intensive cultural resources survey of the entire 55.4-acre (22.4-hectare) project area, including the area immediately surrounding the three jurisdictional water features. Horizon staff archeologists Briana Nicole Smith and Stephanie Mueller, under the overall direction of Jeffrey D. Owens, Principal Investigator, performed an intensive cultural resources survey of the project area on August 23, 2017, to locate any cultural resources that potentially would be impacted by the proposed undertaking. Horizon’s archeologists traversed the project area on foot and thoroughly inspected the modern ground surface for aboriginal and historic-age cultural resources. In addition to pedestrian walkover, the Texas State Minimum Archeological Survey Standards (TSMASS) require a minimum of 1 shovel test per 2.0 acres (0.8 hectare) for tracts between 4.5 and 40.5 hectares (11.0 and 100.0 acres) in size. As such, a minimum of 28 shovel tests would be required within the 22.4-hectare (55.4-acre) project area. Horizon excavated a total of 28 shovel tests, thereby meeting the TSMASS for a project area of this size. In addition, four trenches were excavated using a trackhoe with a 1.8-meter- (6.0-foot-) wide bucket in the vicinity of the USACE jurisdictional tributaries and pond in the southeastern portion of the project area. The trenches were excavated in order to assess the potential for deeply buried cultural resources and the presence of buried paleosols, such as the West Fork paleosol known from farther to the north within the Trinity River basin. Shovel testing revealed dense clay soils that were impenetrable with shovels past an average depth of 30.0 centimeters (11.8 inches) below surface. The four trenches excavated within the southeastern portion of the project area revealed deep alluvial sediments consisting of dense clay overlying sandy clay and sandy clay loam to depths of 5.0 to 5.5 meters (16.4 to 18.0 feet) below surface. Ground surface visibility was low throughout the project area due to dense undergrowth vegetation that has developed subsequent to past vegetation-clearing events. Tall ragweed, greenbrier, and poison ivy covered the majority of the project area as well as occasional clusters of mesquite, oak, and cottonwood trees. No cultural resources, prehistoric or historic-age, were documented on the modern ground surface or within any of the shovel tests or trackhoe trenches excavated within the project area. Furthermore, no evidence of subsurface paleosols was observed in any of the four trackhoe trenches. While shovel testing was not capable of fully penetrating Holocene-age floodplain deposits within the broader project area, all of the deep, clayey alluvial deposits observed in the four trackhoe trenches were culturally sterile, and the stratigraphy observed in trench wall profiles did not suggest any clear boundaries between strata that suggest that stabilized land surfaces were present for any prolonged period of time during the accretion of the floodplain alluvial fills. Based on the results of the survey-level investigations documented in this report, no potentially significant cultural resources would be affected by the proposed undertaking. In accordance with 36 CFR 800.4, Horizon has made a reasonable and good faith effort to identify historic properties within the APE and broader project area. No cultural resources were identified that meet the criteria for listing on the National Register of Historic Places (NRHP) according to 36 CFR 60.4. Horizon recommends a finding of “no historic properties affected,” and no further archeological work is recommended in connection with the proposed undertaking. However, in the event that any human remains or burial objects are inadvertently discovered at any point during construction, use, or ongoing maintenance in the project area, even in previously surveyed areas, all work should cease immediately and the Texas Historical Commission (THC) and/or the USACE, as appropriate, should be notified of the discovery

Neural circuit mechanisms of post–traumatic epilepsy

Traumatic brain injury (TBI) greatly increases the risk for a number of mental health problems and is one of the most common causes of medically intractable epilepsy in humans. Several models of TBI have been developed to investigate the relationship between trauma, seizures, and epilepsy-related changes in neural circuit function. These studies have shown that the brain initiates immediate neuronal and glial responses following an injury, usually leading to significant cell loss in areas of the injured brain. Over time, long-term changes in the organization of neural circuits, particularly in neocortex and hippocampus, lead to an imbalance between excitatory and inhibitory neurotransmission and increased risk for spontaneous seizures. These include alterations to inhibitory interneurons and formation of new, excessive recurrent excitatory synaptic connectivity. Here, we review in vivo models of TBI as well as key cellular mechanisms of synaptic reorganization associated with post-traumatic epilepsy (PTE). The potential role of inflammation and increased blood–brain barrier permeability in the pathophysiology of PTE is also discussed. A better understanding of mechanisms that promote the generation of epileptic activity versus those that promote compensatory brain repair and functional recovery should aid development of successful new therapies for PTE

Brain Injury-Induced Synaptic Reorganization in Hilar Inhibitory Neurons Is Differentially Suppressed by Rapamycin

Following traumatic brain injury (TBI), treatment with rapamycin suppresses mammalian (mechanistic) target of rapamycin (mTOR) activity and specific components of hippocampal synaptic reorganization associated with altered cortical excitability and seizure susceptibility. Reemergence of seizures after cessation of rapamycin treatment suggests, however, an incomplete suppression of epileptogenesis. Hilar inhibitory interneurons regulate dentate granule cell (DGC) activity, and de novo synaptic input from both DGCs and CA3 pyramidal cells after TBI increases their excitability but effects of rapamycin treatment on the injury-induced plasticity of interneurons is only partially described. Using transgenic mice in which enhanced green fluorescent protein (eGFP) is expressed in the somatostatinergic subset of hilar inhibitory interneurons, we tested the effect of daily systemic rapamycin treatment (3 mg/kg) on the excitability of hilar inhibitory interneurons after controlled cortical impact (CCI)-induced focal brain injury. Rapamycin treatment reduced, but did not normalize, the injury-induced increase in excitability of surviving eGFP+ hilar interneurons. The injury-induced increase in response to selective glutamate photostimulation of DGCs was reduced to normal levels after mTOR inhibition, but the postinjury increase in synaptic excitation arising from CA3 pyramidal cell activity was unaffected by rapamycin treatment. The incomplete suppression of synaptic reorganization in inhibitory circuits after brain injury could contribute to hippocampal hyperexcitability and the eventual reemergence of the epileptogenic process upon cessation of mTOR inhibition. Further, the cell-selective effect of mTOR inhibition on synaptic reorganization after CCI suggests possible mechanisms by which rapamycin treatment modifies epileptogenesis in some models but not others