Estimating and Modeling Red Oak Acorn Yield and Abundance in the Mississippi Alluvial Valley

Red oaks (Quercus spp.; Section Erythrobalanus) produce acorns which are valuable forage for wildlife especially mallards (Anas platyrhynchos) and wood ducks (Aix sponsa). Scientists have limited information on amount, timing, and persistence of these acorns in the Mississippi Alluvial Valley (MAV). Conservation planners rely on precise estimates of acorns and other forage to estimate habitat needed by waterfowl in the MAV and other regions. My study provided premiere landscape-scale, multi-year estimates of red oak acorn yield and on-ground abundance in the MAV. Mean yield of acorns was 534 kg(dry)/ha (42.3 acorns/ m2) across all sites, years (falls-winters 2009-2012), and oak species. Yield varied more within years (CV = 11 - 29%) than when data were combined across years (CV = 11%). Yield was not synchronized in any year among MAV sites. However, yield usually was synchronized among species within sites suggesting local factors influenced acorn yield more than landscape-scale factors. Among sites and years, acorn abundance generally was greatest in January (sample mean = 371 kg/ha) and least in November (198 kg/ha). Acorns persisted to February only in years of above-average yield. Except for Nuttall oak (Quercus texana), acorn persistence generally was stable regardless of yield from parent trees. Nuttall oak acorn persistence increased with yield perhaps revealing an evolutionary pressure that encourages masting. Red oak acorn abundance was linearly related to percentage of red oaks in the overstory, but this relationship differed in years of above- and below-average yield. Currently, conservation planners use 166 kg/ha as a forage estimate of red oak acorns, moist-soil seeds, and aquatic macro-invertebrates in bottomland hardwood forests with 100% red oak canopy. I sampled at 5 sites throughout the MAV over 3 years; therefore, I recommend conservation planners consider adopting my predicted estimate of 247 kg of acorns/ha of forest land with 100% red oak canopy. Because acorns persist through most winters and generally reach peak abundance in January, often concomitant with peak abundance of mallards and other ducks in the MAV, biologists and conservation planners may have undervalued the potential of bottomland hardwood forests to support ducks in mid-late winter

Small viscosity behavior of a homogeneous, quasi-geostrophic, ocean circulation mode

Insensitivity to turbulent closure in the wind-driven nonlinear Stommel-Munk model is addressed theoretically and numerically. The QG energy equation is used to show that, with the assumption that the maximum velocities occur at inertial length scales or smaller, a Sverdrup interior is consistent with the small Rossby number assumption only when the frictional parameters exceed critical values. For frictional parameters smaller than these values, valid solutions must decrease the energy source. This is possible for non-Sverdrup solutions since the energy source is dependent on the solution. The steady-state behavior of the model was investigated via a pseudo-arclength continuation algorithm. Dependence on the boundary layer Reynolds number, Re, was investigated by varying the eddy viscosity for fixed wind forcing. A tendency to decrease the energy source was found for solutions that are nonsymmetric about the center latitude. Antisymmetric solutions displayed the opposite behavior and diverged more quickly with increasing Re. The robustness of the results to dynamic boundary condition, symmetry and strength of wind stress, time dependence and bottom friction were tested. Some aspects of the nonsymmetric solutions appeared insensitive to Re

Occupency, Detection, and Co-Occurence Rates of American Black and Mallard Ducks in the Saranac Lakes Wild Forest Area

American black duck populations have steadily decreased across the northeastern United States prompting researchers to examine causes of decline including habitat loss, hybridization with mallards, and competitive exclusion by mallards. We designed a survey of lakes and wetlands of the Saranac Lakes Wild Forest and estimated occupancy and detection rates for each species. Given the predominantly forested landscape and the low density of humans, we predicted American black ducks would have greater occupancy rates than Mallards. Our results show each species was approximately equally likely to occur and to be detected, and there was no evidence that mallards excluded American black ducks from habitats. Mallards did show greater affinity for habitats with more humans present compared to American black ducks. Less than half of the lakes and wetlands we surveyed were occupied by either species indicating there is an abundance of unoccupied habitats that could have population-level ramifications for both species

Effects of large-scale topography on abyssal circulation

Two models are employed to study the effect of topographically induced planetary islands (i.e. closed contours of potential vorticity) on the abyssal circulation of an ocean basin. The first is a steady state calculation using a 1½ layer model of the abyssal ocean forced by a uniform upwelling. Planetary geostrophic dynamics yield a characteristic equation in which the inverse potential vorticity serves as a streamfunction for the characteristic velocity field. Aside from warping the classic Stommel-Arons flow in the immediate vicinity of the planetary island, the topography introduces two new elements to the zonal flow west of the topography. The first of these is a system of two zonal jets, flowing in opposite directions and centered on the separatrix contour. The second is an acceleration (or retardation) of the zonal flow (with respect to the classic flat-bottom result) in a broader region of the basin. The strengths of both the double jets and the broader regions of enhanced/retarded zonal flow are found to be determined by forcing in relatively small areas of the basin. The former are excited in the vicinity of saddle points of potential vorticity whereas the latter are excited primarily where the curvature of potential vorticity contours is large. The second model, a time dependent 2½ layer planetary geostrophic model is then used to investigate the spin-up problem. The model is forced by a uniform upwelling through each of the two interfaces. The density jump at the upper interface (e.g. the thermocline) is chosen to be ten times that at the lower interface, a disparity which leads to a separation in time scale between the fast and the slow waves of the system. Topography, however, induces a strong coupling between these two modes and results in a quick baroclinization of the flow over the topography. This baroclinization occurs well before the arrival of the nondispersive wave front from the eastern boundary and thus differs from the traditional view of spin-up

Microgasification cookstoves and pellet fuels from waste biomass: A cost and performance comparison with charcoal and natural gas in Tanzania

Cooking with wood and wood charcoal is done by over 90% of Africa’s population; it has two major challenges: deforestation and indoor air pollution from cooking smoke, the latter being the top risk factor for disease in Tanzania. Microgasification stoves (top lit up draft [TLUD]) that burn pellets produced from agricultural waste have potential to address both of these issues. We examined the relative efficiency and cost of the major urban cooking fuels - charcoal and liquefied natural gas (LNG) – and compared them to cooking with waste biomass-based pellet fuels; we also compared the performance of three models of natural draft (ND) TLUD stove (Troika, Jiko Bomba, St. John’s) and one forced air (fan) stove (Philips). The Philips and averaged ND stoves used 83 and 133% more pellets by weight respectively to cook beans than charcoal, costing 47 and 93% more at 2013 charcoal and pellet prices. Cooking with LNG costs 387 to 647% more than cooking with charcoal, depending on gas flow rate. The high cost of LNG and LNG stoves will be barriers to the great majority of Tanzanians to move to this improved cookstove technologies (ICTs). Biochar production averaged 59 and 29% of total fuel in the ND and Philips, respectively. Interviews of 30 ND TLUD stove users showed that 60% abandoned use within one month, 80% stating that they produce too much smoke and 40% stating that controlling the air vent is too much trouble. Seventy five percent said that the TLUD cooks significantly faster than charcoal. Due to the continued 33-99% annual increase in charcoal prices in Tanzania, work on introducing TLUD stoves is justified. Key words: Microgasification stoves, TLUD, improved cooking technologies, deforestation, pellet fuels

Efficient Experimental and Data-Centered Workflow for Microstructure-Based Fatigue Data – Towards a Data Basis for Predictive AI Models

Background Early fatigue mechanisms for various materials are yet to be unveiled for the (very) high-cycle fatigue (VHCF) regime. This can be ascribed to a lack of available data capturing initial fatigue damage evolution, which continues to adversely affect data scientists and computational modeling experts attempting to derive microstructural dependencies from small sample size data and incomplete feature representations. Objective The aim of this work is to address this lack and to drive the digital transformation of materials such that future virtual component design can be rendered more reliable and more efficient. Achieving this relies on fatigue models that comprehensively capture all relevant dependencies. Methods To this end, this work proposes a combined experimental and data post-processing workflow to establish multimodal fatigue crack initiation and propagation data sets efficiently. It evolves around fatigue testing of mesoscale specimens to increase damage detection sensitivity, data fusion through multimodal registration to address data heterogeneity, and image-based data-driven damage localization. Results A workflow with a high degree of automation is established, that links large distortion-corrected microstructure data with damage localization and evolution kinetics. The workflow enables cycling up to the VHCF regime in comparatively short time spans, while maintaining unprecedented time resolution of damage evolution. Resulting data sets capture the interaction of damage with microstructural features and hold the potential to unravel a mechanistic understanding. Conclusions The proposed workflow lays the foundation for future data mining and data-driven modeling of microstructural fatigue by providing statistically meaningful data sets extendable to a wide range of materials

Possible Dibaryons with Strangeness s=-5

In the framework of $RGM$, the binding energy of the six quark system with strangeness s=-5 is systematically investigated under the SU(3) chiral constituent quark model. The single $\Xi^*\Omega$ channel calculation with spins S=0 and 3 and the coupled $\Xi\Omega$ and $\Xi^*\Omega$ channel calculation with spins S=1 and 2 are considered, respectively. The results show following observations: In the spin=0 case, $\Xi^* \Omega$ is a bound dibaryon with the binding energy being $80.0 \sim 92.4 MeV$. In the S=1 case, $\Xi\Omega$ is also a bound dibaryon. Its binding energy is ranged from $26.2 MeV$ to $32.9 MeV$. In the S=2 and S=3 cases, no evidence of bound dibaryons are found. The phase shifts and scattering lengths in the S=0 and S=1 cases are also given.Comment: 10 pages, late

A new two-strip TLC method for the quality control of technetium-99m mercaptoacetyl-triglycine (^99mTc-MAG3).

<sup>99m</sup> Tc-mercaptoacetyl-triglycine ( <sup>99m</sup> Tc-MAG3) has been used for dynamic renal imaging since about 30 years. Free pertechnetate ( <sup>99m</sup> TcO <sub>4</sub> ), colloidal <sup>99m</sup> Tc (( <sup>99m</sup> TcO <sub>2</sub> ) <sub>n</sub> ), <sup>99m</sup> Tc-tartrate (precursor), precomplexes ( <sup>99m</sup> Tc-(MAG3) <sub>x</sub> ) and lipophilic <sup>99m</sup> Tc-MAG2 are the main radiochemical impurities that may occur in the preparation. The total amount of these impurities has to be identified before release of the product for patient administration to guarantee patient safety and good image quality. The European Pharmacopoeia suggests a method based on high-pressure liquid chromatography analysis in combination with a paper chromatography. This analytical method is time consuming, expensive and requires specially trained technicians. As a consequence, it is not widely applied in nuclear medicine radiopharmacies. We developed a simple method for radiochemical purity testing of <sup>99m</sup> Tc-MAG3. The method is based on thin layer chromatography with two strips to be developed in parallel. Method validation was carried out in comparison to the official methods of the companies and to the European Pharmacopoeia method. It was tested on specificity, accuracy, robustness and precision. The proposed method is able to identify and quantify the sum of all impurities occurring in the preparation, respecting the acceptance criteria for the radiochemical purity defined by the official methods. Hydrophilic and lipophilic compounds are identified separately and results are obtained within less than 20 minutes. Our method is simple, cost effective, fast and is suitable for employing dose calibrators or radiometric scanners

Winter 1973

Field Evaluation of Insecticides for Controlling Mole Crickets in Turf (page 3) Calculations for Turfgrass Culture II: Pesticides (6) Progress in the Control of Turfgrass Weevil, a Species of Hyperodes (9) A Look at USDA\u27s Biological Control of Insect Pests: 1888 to Present (14) Turf Bulletin Index 1970-1973 (23