Archeological Testing at 41TR170, along the Clear Fork of the Trinity River, Tarrant County, Texas

Archeologists from Geo-Marine, Inc., were subcontracted through Prewitt and Associates, Inc., of Austin to conduct National Register of Historic Places evaluative testing at archeological site 41TR170, located in Tarrant County, Texas. This work (Geo-Marine project number 30353.06.02) was conducted for the Environmental Affairs Division of the Texas Department of Transportation under contract/work authorization 57524SA006. The archeological remains are located on and in the alluvial terrace of the Clear Fork of the Trinity River, within the proposed 130-meter-wide right-of-way of State Highway 121 in southwestern Fort Worth. The work was conducted to comply with Section 106 of the National Historic Preservation Act of 1969, as amended (Public Law 89-665); the Department of Transportation Act of 1966 (Public Law 89-670); and the Antiquities Code of Texas, as incorporated into Title 98, Chapter 191, of the Natural Resources Code of Texas of 1977, as amended. The work was conducted under Texas Antiquities Permit Number 3699 issued by the Texas Historical Commission. A three-stage field tactic was used during the testing of the site. Stage 1, conducted between March 15 and 29, 2005, consisted of archeological monitoring of the mechanical excavation of 28 backhoe trenches, followed by geomorphological field studies of the trench profiles. Trenches were placed both north and south of a relic channel of the Clear Fork of the Trinity River; the present channel was formed in the late 1960s by river-straightening channelization efforts. Efforts were made to ensure archeological sampling of all feature- and artifact-bearing areas previously identified in trenches dug during the 2000 archeological survey. The second stage, which occurred between March 21 and April 29, 2005, involved the manual excavation of 10 test units to depths of 2 meters below surface using standard 10-centimeter-thick levels. The purpose of this phase was to assess the reliability of the backhoe trench monitoring activities and to locate occupation zones worthy of further excavations. The third stage of field investigations was conducted between May 2 and June 3, 2005, and consisted of the mechanical stripping of the overburden above target occupation surfaces and the manual excavation of three block excavations, each 9 square meters, to a depth of 40 centimeters below surface. Upon completion of the fieldwork, a fourth stage comprised a limited analysis to document the nature of the recovered assemblage and to make National Register recommendations about the site, and a final stage was to design a plan for further study or analysis that would then be based on the results of an interim report. The geomorphic investigations, coupled with the processing of eight radiocarbon dates, ascertained that the upper 2 meters of the Clear Fork sediments date to the past 2,900 years. All trenches contained evidence of the regionally dominant West Fork paleosol that is buried under a thin layer of recent alluvium. Beneath the West Fork paleosol were grayish and yellowish clayey strata, and stringers of pea-sized gravels could be correlated to many of the trenches onsite. The substrate for a series of trenches dug into the south edge of the site encountered cemented gravels that likely date to the Pleistocene age. These gravels extend above the Holocene alluvial sediments onsite and provide some minor relief above the floodplain. Although some bioturbation has blurred boundaries between the West Fork paleosol and more recent sediments, the degree of sediment movement is not as pronounced as observed in many other parts of Texas. The excavations generally documented a series of low-density, highly stratified occupations that could not be correlated with any great assurance. The site context and integrity of deposits are generally excellent. Nevertheless, the paucity of remains in most areas is generally insufficient to provide data necessary to address many regional research questions. Site 41TR170 is not unique in this regard, because many sites within the Trinity River basin seem to be short-term specialized logistical extractive activity areas rather than campsites. Two areas of 41TR170, however, seem to be exceptions to low-density, brief occupations and contain a range of features unlike any previously encountered or recorded in the Clear Fork of the Trinity River. In an area located about 60 meters north of the relic river channel, Block 2 exposed part of a deeply buried (180–220 centimeters below surface) ashy zone with abundant charcoal flecks and burned clay daub that occasionally retained impressions of sticks and small posts. Three burned rock features (small pits, scattered rocks, and rock dump concentrations) were found within this ashy zone, but they were not associated with the genesis of the ash. Bone preservation in this zone was good (numbering 121 specimens), but only one stone tool and four pieces of manufacture/maintenance debris were found. Based on the stratigraphic position and the recovery of one unclassified dart point, this feature is possibly Transitional Archaic in affiliation. Indeed, four radiocarbon dates from two features and the top and bottom of the ashy zone reaffirm that the occupation dates between A.D. 540 and 710 (two sigma dates, tree-ring calibrated), and relates to the Transitional Archaic period. The genesis of the thick ashy zone is problematic and not well understood. The radiocarbon dates suggest that the 40-centimeter-thick ashy zone did not develop instantaneously but rather apparently accumulated over a span of about 180 years (ca. 1,270 and 1,450 years ago). Even though a few rock features and some relatively high density of bone are preserved in this ashy sediment, the low density of remains suggests that the deposit cannot be considered an occupation midden. The age range also suggests that this is not a burned architectural structure. The formation process resulting in a 40-centimeter-thick ashy zone remains unknown. In an area almost 150 meters south of the relic channel, an extensive area of burned rock covering at least 12-x-12 meters was encountered. Noncontiguous Blocks 1 and 3 were opened to explore the variability of burned rock features and ascertain the kinds of remains present. The recovery of two dart points (a Trinity and a Yarbrough) at comparable depths of 90 to 130 centimeters below surface suggests that this area along the edge of the Pleistocene gravel terrace was repeatedly occupied during the Late Archaic period. Among the burned rock features revealed in Block 3 was one large incipient burned rock oven with a pit measuring 2.54 meters in diameter surrounded by a discard ring of burned rocks that were only some 20 centimeters thick. Another cluster of burned rock more deeply buried in the sediments suggests multiple occupations. In adjacent Block 1 were two smaller (possible) pit ovens about 1 meter in diameter, an elongated pile of rock stored for reuse, a few rake-off piles or dumps, and one area of fitted burned rock that might have served as a large griddle-like feature. Tools and chipped stone debris were moderately abundant in Block 1, but rare in Block 3. Bone preservation in this area was very poor, although several hundred fragments of scattered freshwater mussel shell were present. Analysis of shell umbos or hinges indicates that about 59 shells were present in Block 1 and only 50 hinges in Block 3; none were concentrated into discrete discard features. The size, density, and morphological variability of the burned rock features are unlike anything previously seen in the Trinity River basin. Four radiocarbon dates from Blocks 1 and 3 suggest that the series of occupations date between A.D. 540 and 780 (2-sigma dates, tree-ring calibrated). Indeed the radiocarbon dates indicate that the activities resulting in the accumulation of dense burned rock features exposed in Blocks 1 and 3 are culturally contemporaneous with the activities occurring in the thick ashy zone located some 170 to 210 meters apart, even though they undoubtedly represent multiple reuse of the area. The two areas may not have been occupied simultaneously, for the low artifact density suggests that comparable groups of people from the Transitional Archaic period made the distinctly different occupational signatures in the two areas. The testing phase of work at 41TR170 has documented considerable variability in feature forms during the Transitional Archaic period for the Trinity River basin. Test probes also strongly suggest that many more burned rock features occur parallel to the Pleistocene gravel terrace. In this regard, the testing has not exhausted the information potential related to the spatial patterning in activities by these people. However, the associated stone, shell, and bone artifact assemblages are relatively meager. Similarly, extensive flotation has failed to find any macrobotanical remains other than a single nutshell and small amounts of wood charcoal. Efforts to retrieve lipids samples from the burned rock feature proved to be successful, but the results were not very helpful in providing insight into the diversity of feature activities. Although examination of more burned rock features may stumble on examples of cooking accidents that preserve ancient foodstuff, the current robust level of testing suggests that the information content from the site is relatively limited. For this reason, even though the site is of considerable interest from a regional perspective, the site seemingly does not have the potential to make further contributions to the knowledge of the region. Thus, site 41TR170 fails to meet the standards of Criterion D or any other significance standard required for assessing National Register eligibility. Site 41TR170 is recommended as not eligible for National Register inclusion, and no further archeological investigations are recommended

Selective coherence transfers in homonuclear dipolar coupled spin systems

Mapping the physical dipolar Hamiltonian of a solid-state network of nuclear spins onto a system of nearest-neighbor couplings would be extremely useful for a variety of quantum information processing applications, as well as NMR structural studies. We demonstrate such a mapping for a system consisting of an ensemble of spin pairs, where the coupling between spins in the same pair is significantly stronger than the coupling between spins on different pairs. An amplitude modulated RF field is applied on resonance with the Larmor frequency of the spins, with the frequency of the modulation matched to the frequency of the dipolar coupling of interest. The spin pairs appear isolated from each other in the regime where the RF power (omega_1) is such that omega_weak << omega_1 << omega_strong. Coherence lifetimes within the two-spin system are increased from 19 us to 11.1 ms, a factor of 572.Comment: 4 pages. Paper re-submitted with minor changes to clarify that the scheme demonstrated is not an exact mapping onto a nearest neighbor system. However, this is the first demonstration of a controlled evolution in a subspace of an extended spin system, on a timescale that is much larger than the dipolar dephasing tim

Targeting NKG2D ligands in glioblastoma with a bispecific T-cell engager is augmented with conventional therapy and enhances oncolytic virotherapy of glioma stem-like cells

Background: Glioblastoma (GBM) almost invariably becomes resistant towards conventional treatment of radiotherapy and temozolomide (TMZ) chemotherapy, partly due to subpopulations of intrinsically resistant glioma stem-like cells (GSC). The oncolytic herpes simplex virus-1 G207 is a promising approach for GBM virotherapy although its efficacy in patients with GBM is often limited. Natural killer group 2 member D ligands (NKG2DLs) are minimally expressed by healthy cells but are upregulated by the DNA damage response (DDR) and in malignant cells with chronic DDR signaling, resulting in innate immune activation. Methods: We have designed a bispecific T-cell engager (BiTE) capable of cross-linking CD3 on T cells with NKG2DL-expressing GBM cells. We then engineered the G207 virus to express the NKG2D BiTE and secrete it from infected cells. The efficacy of the free BiTE and BiTE delivered by G207 was evaluated in combination with conventional therapies in GBM cells and against patient-derived GSCs in the context of T-cell activation and target cell viability. Results: NKG2D BiTE-mediated cross-linking of GBM cells and T cells causes antigen-independent T-cell activation, pro-inflammatory cytokine release, and tumor cell death, thereby combining direct viral oncolysis with BiTE-mediated cytotoxicity. Surface NKG2DL expression was further elevated on GBM cells following pretreatment with sublethal doses of TMZ and radiation to induce the DDR, increasing sensitivity towards G207-NKG2D BiTE and achieving synergistic cytotoxicity. We also demonstrate a novel strategy for targeting GSCs that are non-permissive to G207 infection but remain sensitive to NKG2D BiTE. Conclusions: We propose a potential model for targeting GSCs in heterogeneous tumors, whereby differentiated GBM cells infected with G207-NKG2D BiTE produce NKG2D BiTE locally, directing T-cell cytotoxicity towards the GSC subpopulations in the tumor microenvironment

The Evolution of Dust Opacity in Galaxies

(Abridged) We investigate the evolution of the opacity of galaxies as a function of redshift, using simple assumptions about the metal and dust enrichment of the gas and the distribution of dust in galaxies. We use an iterative procedure to reconstruct the intrinsic Star Formation Rate (SFR) density of galaxies with redshift, by applying dust obscuration corrections to the observed UV emission. The iterative procedure converges to multiple solutions for the intrinsic SFR density, divided into two basic classes. The first class of solutions predicts relatively large UV attenuation at high redshift, with A(1500 A)=1.9 mag at z~3, and smaller attenuations at z<1, with A(2800 A)=1.25 mag. The SFR density of this set of solutions is constant for z>~1.2 and declines for z<1.2; it resembles in shape the ``monolithic collapse'' scenario for star formation. The second class of solutions predicts relatively low UV attenuations at high redshift, with A(1500 A)=0.75 mag at z~3, and larger attenuations at z<1, with A(2800 A)=1.50 mag. The SFR density in this case has a peak at z~1.2. The advantages and shortcomings of both classes are analyzed in the light of available observational constraints, including the opacity of galaxies at 0<z<1 and the intensity and spectral energy distribution of the cosmic infrared background from the COBE DIRBE and FIRAS data. We conclude that both classes of models are acceptable within the current uncertainties, but the ``monolithic collapse'' class matches the available observations better than the other one. We also investigate the dependence of our solutions on the different model assumptions.Comment: 54 pages, includes 1 embedded postscript Table and 22 embedded postscript Figures, Latex, uses AAS Latex macro. Accepted for publication in the Astrophysical Journa

Clinical, radiologic, pathologic, and molecular characteristics of long-term survivors of diffuse intrinsic pontine glioma (DIPG): a collaborative report from the International and European Society for Pediatric Oncology DIPG registries

Purpose Diffuse intrinsic pontine glioma (DIPG) is a brainstem malignancy with a median survival of &lt; 1 year. The International and European Society for Pediatric Oncology DIPG Registries collaborated to compare clinical, radiologic, and histomolecular characteristics between short-term survivors (STSs) and long-term survivors (LTSs). Materials and Methods Data abstracted from registry databases included patients from North America, Australia, Germany, Austria, Switzerland, the Netherlands, Italy, France, the United Kingdom, and Croatia. Results Among 1,130 pediatric and young adults with radiographically confirmed DIPG, 122 (11%) were excluded. Of the 1,008 remaining patients, 101 (10%) were LTSs (survival ≥ 2 years). Median survival time was 11 months (interquartile range, 7.5 to 16 months), and 1-, 2-, 3-, 4-, and 5-year survival rates were 42.3% (95% CI, 38.1% to 44.1%), 9.6% (95% CI, 7.8% to 11.3%), 4.3% (95% CI, 3.2% to 5.8%), 3.2% (95% CI, 2.4% to 4.6%), and 2.2% (95% CI, 1.4% to 3.4%), respectively. LTSs, compared with STSs, more commonly presented at age &lt; 3 or &gt; 10 years (11% v 3% and 33% v 23%, respectively; P &lt; .001) and with longer symptom duration ( P &lt; .001). STSs, compared with LTSs, more commonly presented with cranial nerve palsy (83% v 73%, respectively; P = .008), ring enhancement (38% v 23%, respectively; P = .007), necrosis (42% v 26%, respectively; P = .009), and extrapontine extension (92% v 86%, respectively; P = .04). LTSs more commonly received systemic therapy at diagnosis (88% v 75% for STSs; P = .005). Biopsies and autopsies were performed in 299 patients (30%) and 77 patients (10%), respectively; 181 tumors (48%) were molecularly characterized. LTSs were more likely to harbor a HIST1H3B mutation (odds ratio, 1.28; 95% CI, 1.1 to 1.5; P = .002). Conclusion We report clinical, radiologic, and molecular factors that correlate with survival in children and young adults with DIPG, which are important for risk stratification in future clinical trials

Weak Lensing Measurements of 42 SDSS/RASS Galaxy Clusters

We present a lensing study of 42 galaxy clusters imaged in Sloan Digital Sky Survey (SDSS) commissioning data. Cluster candidates are selected optically from SDSS imaging data and confirmed for this study by matching to X-ray sources found independently in the ROSAT all sky survey (RASS). Five color SDSS photometry is used to make accurate photometric redshift estimates that are used to rescale and combine the lensing measurements. The mean shear from these clusters is detected to 2 h-1 Mpc at the 7-sigma level, corresponding to a mass within that radius of 4.2 +/- 0.6 x 10^14 h-1 M_sun. The shear profile is well fit by a power law with index -0.9 +/- 0.3, consistent with that of an isothermal density profile. This paper demonstrates our ability to measure ensemble cluster masses from SDSS imaging data.Comment: 14 pages, 7 figures, Accepted for publication in Ap

The DEEP Groth Strip Galaxy Redshift Survey. VIII. The Evolution of Luminous Field Bulges at Redshift z ~ 1

We present a sample of over 50 luminous field bulges (including ellipticals) found in the Groth Strip Survey (GSS), with 0.73< z < 1.04 and with bulge magnitudes I <= 23. The exponential disk light is removed via decomposition of HST images using GIM2D. We find that 85% of these bulges are nearly as red as local E/S0's and have a shallow slope and a small color dispersion in the color-luminosity relation, suggesting roughly coeval formation. The surface brightnesses of these bulges are about 1 mag higher than local bulges. These results are explained adopting a "drizzling" scenario where a metal-rich early formation is later polluted by small amounts of additional star formation. Almost all disks have the same or bluer colors than their accompanying bulges, regardless of the bulge-disk ratio and bulge luminosity, as expected from semi-analytic hierarchical galaxy formation models. We present evidence that the few blue bulge candidates are not likely to be genuine blue ellipticals or bulges. Our deeper, more extensive, and less disk-contaminated observations challenge prior claims that 30% to 50% of field bulges or ellipticals are in a blue, star-forming phase at z < 1. We conclude that field bulges and ellipticals at z ~ 1, like luminous early- type cluster galaxies at the same redshift, are already dominated by metal-rich, old stellar populations that have been fading from a formation epoch earlier than z ~ 1.5. (abridged)Comment: ApJS accepted, 106 pages, 10 figures. Figure 14 in JPEG format. Full version available at http://deep.ucolick.org/publications.htm

Basal Immunoglobulin Signaling Actively Maintains Developmental Stage in Immature B Cells

In developing B lymphocytes, a successful V(D)J heavy chain (HC) immunoglobulin (Ig) rearrangement establishes HC allelic exclusion and signals pro-B cells to advance in development to the pre-B stage. A subsequent functional light chain (LC) rearrangement then results in the surface expression of IgM at the immature B cell stage. Here we show that interruption of basal IgM signaling in immature B cells, either by the inducible deletion of surface Ig via Cre-mediated excision or by incubating cells with the tyrosine kinase inhibitor herbimycin A or the phosphatidylinositol 3-kinase inhibitor wortmannin, led to a striking “back-differentiation” of cells to an earlier stage in B cell development, characterized by the expression of pro-B cell genes. Cells undergoing this reversal in development also showed evidence of new LC gene rearrangements, suggesting an important role for basal Ig signaling in the maintenance of LC allelic exclusion. These studies identify a previously unappreciated level of plasticity in the B cell developmental program, and have important implications for our understanding of central tolerance mechanisms

Quantifying the impact of mergers on the angular momentum of simulated galaxies.

We use EAGLE to quantify the effect galaxy mergers have on the stellar specific angular momentum of galaxies, jstars. We split mergers into dry (gas-poor)/wet (gas-rich), major/minor and different spin alignments and orbital parameters. Wet (dry) mergers have an average neutral gas-to-stellar mass ratio of 1.1 (0.02), while major (minor) mergers are those with stellar mass ratios ≥0.3 (0.1–0.3). We correlate the positions of galaxies in the jstars–stellar mass plane at z = 0 with their merger history, and find that galaxies of low spins suffered dry mergers, while galaxies of normal/high spins suffered predominantly wet mergers, if any. The radial jstars profiles of galaxies that went through dry mergers are deficient by ≈0.3 dex at r ≲ 10 r50 (with r50 being the half-stellar mass radius), compared to galaxies that went through wet mergers. Studying the merger remnants reveals that dry mergers reduce jstars by ≈30 per cent, while wet mergers increase it by ≈10 per cent, on average. The latter is connected to the build-up of the bulge by newly formed stars of high rotational speed. Moving from minor to major mergers accentuates these effects. When the spin vectors of the galaxies prior to the dry merger are misaligned, jstars decreases by a greater magnitude, while in wet mergers corotation and high orbital angular momentum efficiently spun-up galaxies. We predict what would be the observational signatures in the jstars profiles driven by dry mergers: (i) shallow radial profiles and (ii) profiles that rise beyond ≈10 r50, both of which are significantly different from spiral galaxies