Surface-water groundwater interactions in the Middle Rio Grande, NM Implications for bank storage and native species

Riparian zones are important for ecological purposes and ecosystem processes, and are valued for aesthetic, recreational, cultural, and historical reasons. The declining integrity of cottonwood-dominated riparian systems in the Middle Rio Grande (MRG) of central New Mexico has been evident for several decades, of which the largest cause has been the severe alterations riparian hydrology. While cottonwood germination responses to changing flood regimes have been well studied, the response to changing groundwater dynamics - and the suitability of groundwater regimes in the MRG - is less well understood. This study used pressure transducer groundwater datasets installed in the Rio Grande riparian zone by the Bosque Ecosystem Monitoring Program (BEMP) to investigate groundwater behavior in the MRG and its impact on bank storage, cottonwood recruitment, and native riparian integrity. A relational database of BEMP’s groundwater data was constructed, and its utility was assessed. It was concluded that BEMP’s data are largely accurate, with some exceptions. Time series analysis of the data indicated that riparian groundwater responds rapidly to changes in streamflow, and that bank storage is transient and does not extend far from the river channel. This may be caused by agricultural drains, which induce an uncharacteristic permanent hydraulic gradient sloping away from the river. This gradient intercepts bank storage and causes rapid groundwater recessions after high discharge events. At all study sites but one, groundwater recession is controlled directly by the rate of discharge decline, and often exceeded the maximum rate tolerable by cottonwood seedlings. A single successful cottonwood recruitment event in 2009 at one of the sites was captured in the pressure transducer record. Groundwater observations from this event indicate that cottonwood seedlings can tolerate relatively rapid recession rates, as long as these rates are not prolonged, or are interspersed with slower or negligible rates. Ultimately, the primary difference between present day conditions and when large-scale recruitment events occurred is the flow regime of the Rio Grande and loss of high-discharge flood events

Constructing free actions of p-groups on products of spheres

We prove that, for p an odd prime, every finite p-group of rank 3 acts freely on a finite complex X homotopy equivalent to a product of three spheres

Short Course for Focused Assessment with Sonography for Human Immunodeficiency Virus/Tuberculosis: Preliminary Results in a Rural Setting in South Africa with High Prevalence of Human Immunodeficiency Virus and Tuberculosis

In Africa, human immunodeficiency virus (HIV)–associated extrapulmonary tuberculosis (TB) is common and poses diagnostic difficulties. Ultrasound is useful to find suggestive signs such as effusions or abdominal lymphadenopathy. Because trained radiologists are scarce in resource-poor settings, even this simple and relatively inexpensive diagnostic tool is frequently unavailable to patients in district hospitals in sub-Saharan Africa. We developed a focused protocol for assessment with sonography for HIV/TB and trained physicians in a rural district hospital in South Africa. In this pilot study, high levels of confidence in identifying specific signs were rapidly achieved and ultrasound was introduced into routine clinical practice

Covid-19: Better contact tracing could help save lives and the economy

The rates of daily infections are rising significantly. In order to save lives and to keep the UK economy open, improvements to the UK contact tracing system are urgently needed. Woolliscroft et al. outlined how the UK contact tracing system could be improved. Detailed evaluation of the Sheffield based community contact tracing pilot project offers additional insights. [1,2] An independent group of mainly retired NHS staff called Sheffield Community Contact Tracers (SCCT) conducted a pilot contact tracing project from April to May 2020 before the national system was introduced. The project was assessed to determine the feasibility and impact of a volunteer staffed community contact tracing approach. The assessment found that contact tracing was enhanced by: trust, local knowledge, interviewer skills and expertise, cooperation from employers, and contact in a timely manner

Finite Temperature Lattice QCD with Clover Fermions

We report on our simulation of finite temperature lattice QCD with two flavors of ${\cal O}(a)$ Symanzik-improved fermions and ${\cal O}(a^2)$ Symanzik-improved glue. Our thermodynamic simulations were performed on an $8^3 \times 4$ lattice, and we have performed complementary zero temperature simulations on an $8^3 \times 16$ lattice. We compare our results to those from simulations with two flavors of Wilson fermions and discuss the improvement resulting from use of the improved action.Comment: 3 pages, 4 figures, Talk presented at Lattice 9

Exotic hybrid mesons with light quarks

Hybrid mesons, made from a quark, an antiquark and gluons, can have quantum numbers inaccessible to conventional quark-antiquark states. Confirmation of such states would give information on the role of "dynamical" color in low energy QCD. We present preliminary results for hybrid meson masses using light Wilson valence quarks.Comment: 4 pages, 4 figures, Talk presented at LATTICE96(spectrum

Update on the hadron spectrum with two flavors of staggered quarks

We present an update on the MILC Collaboration's light hadron spectrum calculation with two flavors of dynamical, staggered quarks. We present extrapolations of the nucleon to rho mass ratio to the continuum limit for fixed values of the pi to rho mass ratio including the physical one.Comment: 3 pages, LaTex with espcrc2 and epsf, 5 postscript figures included, Lattice '97 Proceeding

Heavy-light decay constants---MILC results with the Wilson action

We present the current status of our ongoing calculations of pseudoscalar meson decay constants for mesons that contain one light and one heavy quark (f_B, f_{B_s}, f_D, f_{D_s}). We are currently generating new gauge configurations that include dynamical quarks and calculating the decay constants. In addition, we have several new results for the static approximation. Those results, as well as several refinements to the analysis, are new since Lattice '96. Our current (still preliminary) value for f_B is 156 +- 11 +- 30 +- 14 MeV, where the first error is from statistical and fitting errors, the second error is an estimate of other systematic errors within the quenched approximation and the third error is an estimate of the quenching error. For the ratio f_{B_s}/f_B, we get 1.11 +- 0.02 +- 0.03 +- 0.07.Comment: 8 pages, 9 figures, LaTeX, uses espcrs2, epsf, Invited talk presented by S. Gottlieb at Lattice QCD on Parallel Computers, University of Tsukuba, March, 1997, to appear in the proceeding