The first record of Merycomyia whitneyi (Johnson), tribe Bouvieromyiini (Diptera: Tabanidae), from Texas and from west of the Mississippi River

The first collections of Merycomyia whitneyi (Johnson), (Diptera: Tabanidae: Chrysopsinae: Bouvieromyiini) from Texas and from west of the Mississippi River are reported, and the Nearctic species of the Tribe Bouvieromyiini are discussed

Bronze Age Subsistence Change at Regional and Microscopic Scales in Northeast China

This article investigates Late Bronze Age mobile pastoralism in Northeast China. Analysis of the use-wear patterns provides direct evidence speaking to the subsistence economies during the Bronze Age. The patterns of use-wear are compared to the settlement patterning and environmental contexts to test proposed theories about whether and how subsistence change takes place. The results indicate continuity in mixed animal and plant based economies in both the Early and Late Bronze Age despite changes in climate and population. The relative intensity of economic practice is guided by the environmental context, but this is detected only at the sub-regional level

Improving LLR Tests of Gravitational Theory

Accurate analysis of precision ranges to the Moon has provided several tests of gravitational theory including the Equivalence Principle, geodetic precession, parameterized post-Newtonian (PPN) parameters $\gamma$ and $\beta$, and the constancy of the gravitational constant {\it G}. Since the beginning of the experiment in 1969, the uncertainties of these tests have decreased considerably as data accuracies have improved and data time span has lengthened. We are exploring the modeling improvements necessary to proceed from cm to mm range accuracies enabled by the new Apache Point Observatory Lunar Laser-ranging Operation (APOLLO) currently under development in New Mexico. This facility will be able to make a significant contribution to the solar system tests of fundamental and gravitational physics. In particular, the Weak and Strong Equivalence Principle tests would have a sensitivity approaching 10$^{-14}$, yielding sensitivity for the SEP violation parameter $\eta$ of $\sim 3\times 10^{-5}$, $v^2/c^2$ general relativistic effects would be tested to better than 0.1%, and measurements of the relative change in the gravitational constant, $\dot{G}/G$, would be $\sim0.1$% the inverse age of the universe. Having this expected accuracy in mind, we discusses the current techniques, methods and existing physical models used to process the LLR data. We also identify the challenges for modeling and data analysis that the LLR community faces today in order to take full advantage of the new APOLLO ranging station.Comment: 15 pages, 3 figures, talk presented at 2003 NASA/JPL Workshop on Fundamental Physics in Space, April 14-16, 2003, Oxnard, C

Response of a gall-forming guild (Hymenoptera: Cynipidae) to stressed and vigorous prairie roses

Two general hypotheses that describe the relationship between plant quality and host-plant preference of insect herbivores are the plant-stress and plant-vigor hypotheses. We examined the response of a gall-forming guild of insect herbivores associated with prairie rose, Rosa arkansana Porter (Rosaceae), to experimental manipulations of plant stress (addition of NaCl) and vigor (addition of nitrogen; NH4NO3). The most common members of the gall-forming guild on roses are Diplolepis ignota Osten Sacken, D. nodulosa Beutenmüller, and D. rosaefolii Cockerell (Hymenoptera: Cynipidae). The repeated application of nitrogen throughout the growing season to prairie plots resulted in significantly higher plant nitrogen levels and plant growth rates. Both low and high NaCl additions caused leaves to turn yellow and wilt, but reductions in rose growth rates or xylem water potentials with NaCl additions were not statistically significant. All three members of the cynipid guild responded similarly to nitrogen and NaCl additions to rose plots. Incidence of occurrence and density within a plot decreased with increasing nitrogen or NaCl, but the decline associated with increasing NaCl was not significant for any of the cynipids. Neither the plant-vigor hypothesis (higher abundance on fast-growing, vigorous plants) nor the plant-stress hypothesis (higher abundance on physiologically stressed plants) was supported by this study. For cynipids, there is growing evidence that larvae perform best on plant tissues low in nitrogen (less vigorous plants). Agricultural runoff, of which nitrogen is an important constituent, may be significantly altering cynipid distributions and their interactions with other members of the tall-grass prairie ecosystem

Petrology and geochemistry of nakhlite MIL 03346: A new Martian meteorite from Antarctica

MIL 03346 is the first nakhlite in the US Antarctic collection. We have performed detailed mineralogical and bulk-geochemical investigations to compare petrogenesis of this Martian meteorite with other nakhlites

Bone-to-bone and implant-to-bone impingement : a novel graphical representation for hip replacement planning

Bone-to-bone impingement (BTBI) and implant-to-bone impingement (ITBI) risk assessment is generally performed intra-operatively by surgeons, which is entirely subjective and qualitative, and therefore, lead to sub-optimal results and recurrent dislocation in some cases. Therefore, a method was developed for identifying subject-specific BTBI and ITBI, and subsequently, visualising the impingement area on native bone anatomy to highlight where prominent bone should be resected. Activity definitions and subject-specific bone geometries, with planned implants were used as inputs for the method. The ITBI and BTBI boundary and area were automatically identified using ray intersection and region growing algorithm respectively to retain the same ‘conical clearance angle’ obtained to avoid prosthetic impingement (PI). The ITBI and BTBI area was then presented with different colours to highlight the risk of impingement, and importance of resection. A clinical study with five patients after 2 years of THA was performed to validate the method. The results supported the study hypothesis, in that the predicted highest risk area (red coloured zone) was completely/majorly resected during the surgery. Therefore, this method could potentially be used to examine the effect of different pre-operative plans and hip motions on BTBI, ITBI, and PI, and to guide bony resection during THA surgery

Multivariate side-band subtraction using probabilistic event weights

A common situation in experimental physics is to have a signal which can not be separated from a non-interfering background through the use of any cut. In this paper, we describe a procedure for determining, on an event-by-event basis, a quality factor ($Q$-factor) that a given event originated from the signal distribution. This procedure generalizes the "side-band" subtraction method to higher dimensions without requiring the data to be divided into bins. The $Q$-factors can then be used as event weights in subsequent analysis procedures, allowing one to more directly access the true spectrum of the signal.Comment: 17 pages, 9 figure

A Comparison of Traffic Sign Comprehension Using Static, Dynamic and Interactive Media

Traditionally, traffic sign comprehension has been tested using paper-and-pencil tests with line drawings of signs and uncontrolled viewing time of the test signs. This study compares these types of tests to dynamic tests using an interactive driving simulator. Multiple-choice tests concerning sign comprehension were administered to five groups of Texas drivers following exposure to traffic sign stimuli via line drawings, still computer drawings in a roadway context either with or without controlled exposure, a video of a “drive through” from the simulator, or driving in the simulator itself. Results show interesting differences among the groups that suggest that past studies may have overestimated sign comprehension

A Comparison of Traffic Sign Comprehension Using Static, Dynamic and Interactive Media

Traditionally, traffic sign comprehension has been tested using paper-and-pencil tests with line drawings of signs and uncontrolled viewing time of the test signs. This study compares these types of tests to dynamic tests using an interactive driving simulator. Multiple-choice tests concerning sign comprehension were administered to five groups of Texas drivers following exposure to traffic sign stimuli via line drawings, still computer drawings in a roadway context either with or without controlled exposure, a video of a “drive through” from the simulator, or driving in the simulator itself. Results show interesting differences among the groups that suggest that past studies may have overestimated sign comprehension

Progress in Lunar Laser Ranging Tests of Relativistic Gravity

Analyses of laser ranges to the Moon provide increasingly stringent limits on any violation of the Equivalence Principle (EP); they also enable several very accurate tests of relativistic gravity. We report the results of our recent analysis of Lunar Laser Ranging (LLR) data giving an EP test of \Delta (M_G/M_I)_{EP} =(-1.0 +/- 1.4) x 10^{-13}. This result yields a Strong Equivalence Principle (SEP) test of \Delta (M_G/M_I)_{SEP} =(-2.0 +/- 2.0) x 10^{-13}. Also, the corresponding SEP violation parameter \eta is (4.4 +/- 4.5) x 10^{-4}, where \eta=4\beta-\gamma-3 and both \beta and \gamma are parametrized post-Newtonian (PPN) parameters. Using the recent Cassini result for the parameter \gamma, PPN parameter \beta is determined to be \beta-1=(1.2 +/- 1.1) x 10^{-4}. The geodetic precession test, expressed as a relative deviation from general relativity, is K_{gp}=-0.0019 +/- 0.0064. The search for a time variation in the gravitational constant results in \dot G/G=(4 +/- 9) x 10^{-13} yr^{-1}, consequently there is no evidence for local (~1AU) scale expansion of the solar system.Comment: 4 pages, revtex4, minor changes made for publicatio