Formation of Cosmic Dust Bunnies

Planetary formation is an efficient process now thought to take place on a relatively short astronomical time scale. Recent observations have shown that the dust surrounding a protostar emits more efficiently at longer wavelengths as the protoplanetary disk evolves, suggesting that the dust particles are coagulating into fluffy aggregates, "much as dust bunnies form under a bed." One poorly understood problem in this coagulation process is the manner in which micron-sized, charged grains form the fractal aggregate structures now thought to be the precursors of protoplanetary disk evolution. This study examines the characteristics of such fractal aggregates formed by the collision of spherical monomers and aggregates where the charge is distributed over the aggregate structure. The aggregates are free to rotate due to collisions and dipole-dipole electrostatic interactions. Comparisons are made for different precursor size distributions and like-charged, oppositelycharged, and neutral grains

Bat Activity Patterns and Roost Selection in Managed Forests

The recent introduction and subsequent westward spread of white-nose syndrome (WNS) has decimated hibernating bat populations in eastern North America and created an urgent need for scientists to understand basic information about bat ecology, especially during the winter season. White-nose syndrome has killed between 5 and 7 million bats and continues to spread westward from the eastern U.S. and southern Canada, primarily affecting bats during hibernation. Acoustic monitoring has been suggested as a potential surveillance tool for detecting WNS; however, baseline information must first be collected to test this technique.  Recent interests in habitat for resident bats has focused on managed forests, particularly in western Montana, where caves used as communal winter hibernacula are not abundant.  We initiated a pilot project in June 2014 deploying 2 remote acoustic monitoring stations on Plum Creek property in Flathead County and adding an additional 2 stations in forests owned by Stoltze Land and Lumber and Stimson Lumber Company in May 2015 to collect baseline acoustic information. We also conducted radio telemetry to determine characteristics of roosts used by bats during the fall season in 2014 and 2015. Thus far we have acoustically detected 11 of Montana’s 15 bat species, observed extremely high activity levels during the summer, and detected bat activity during every month of the year. We radio-tagged 14 bats of 4 different species; California myotis (Myotis californicus), Western small-footed myotis (Myotis ciliolabrum), Silver-haired bat (Lasionycteris noctivagans), Little brown bat (Myotis lucifugus) and tracked them in late October and early November. Identifying the characteristics of roost sites used during the pre-hibernation period, and the annual activity patterns determined from acoustic monitoring, begin to form the foundation for understanding basic aspects of bat ecology during the season when Montana bats will be most susceptible to WNS

Bat Activity Patterns and Roost Selection in Managed Forests

The recent introduction and subsequent westward spread of white-nose syndrome (WNS) has decimated hibernating bat populations in eastern North America and created an urgent need for scientists to understand basic information about bat ecology, especially during the winter season. White-nose syndrome has killed between 5 and 7 million bats and continues to spread westward from the eastern U.S. and southern Canada, primarily affecting bats during hibernation. Acoustic monitoring has been suggested as a potential surveillance tool for detecting WNS; however, baseline information must first be collected to test this technique.  We initiated a pilot project in June 2014 by deploying 2 remote acoustic monitoring stations in western Montana’s managed forests collecting baseline acoustic information. We also conducted radio telemetry to determine characteristics of roosts used by bats during the fall season. Thus far we have recorded 11 of Montana’s 15 bat species, and observed extremely high activity levels during the summer. We radio-tagged 5 bats of 3 different species (California myotis, Western small-footed myotis, Silver-haired bat) and tracked them in late October and early November. Identifying the characteristics of roost sites used during the pre-hibernation period, and the annual activity patterns determined from acoustic monitoring, begin to form the foundation for understanding basic aspects of bat ecology during the season when Montana bats will be most susceptible to WNS

Specificity characteristics of 7 commercial creatinine measurement procedures by enzymatic and jaffe method principles

Journal ArticleStandardized calibration does not change a creatinine measurement procedure?s susceptibility to potentially interfering substances

Bulletin No. 385 - Comparitive Nutritive Value and Palatability of Some Introduced and Native Forage Plants for Spring and Summer Grazing

From 1952 to 1954 studies were conducted on foothill ranges of central Utah to determine the forage production, palatability, and nutritive value of some of the more important native and introduced species used for spring and summer grazing. Plants studied were four introduced wheatgrasses (crested, tall, pubescent, and intermediate) , four native grasses (western wheatgrass, beardless wheatgrass, squirreltail grass, and Indian ricegrass), and two introduced annual forbs (Russian-thistle, and smother weed). Field digestibility trials were conducted to determine the nutrient content by the lignin-ratio technique. In addition, both sheep and cattle preferences were studied on areas where both introduced and native species were planted

Control of drying shrinkage of magnesium silicate hydrate gel cements

Cracks were observed when the magnesium silicate hydrate gel cement (prepared by 40% MgO/60% silica fume) was dried. This drying cracking is believed to be caused when unbound water evaporates from the binder. The shrinkage upon forced drying to 200 °C of mortars made up from a reactive magnesium oxide, silica fume and sand was measured using dilatometry. The magnitude of the drying shrinkage was found to decrease when more sand or less water was added to the mortars and can be as low as 0.16% for a mortar containing 60 wt% sand and a water to cement ratio of 0.5, which is of a similar order of magnitude as observed in Portland cement based mortars and concretes. A simple geometrical interpretation based on packing of the particles in the mortar can explain the observed drying shrinkages and based on this analysis the drying shrinkage of the hydration products at zero added solid is estimated to be 7.3% after 7 days of curing

Making it stick: The secret to developing a data-driven culture

Big data and analytics has been recognized as fundamental to an organization’s success has consistently identified as one of top 10 Workforce Trends in recent years. One of the final steps in an analytics or applied research project is deployment where a solution is integrated into business practices. Without cultural acceptance, however, organizations risk missing out on the full impact that data and evidence-based practices can deliver. Even with data and analytics solutions deployed in business procedures, employees may still make decisions based on hunches and instinct. In order to harness the full potential of data analytics, organizations need to develop a culture that moves from “What do we think?” to “What do we know?”. Cultural change can be one of the most difficult things to effect in an organization, and transitioning to a data-driven culture has numerous challenges. Presenters will discuss strategies for gaining organizational commitment to data-driven decision-making, by increasing employee understanding of the value of evidence-based practices, and how data and analytics can be applied to decision-making

Origin of the spin reorientation transitions in (Fe1−x_{1-x}Cox_{x})2_{2}B alloys

Low-temperature measurements of the magnetocrystalline anisotropy energy $K$ in (Fe$_{1-x}$Co$_{x}$)$_{2}$B alloys are reported, and the origin of this anisotropy is elucidated using a first-principles electronic structure analysis. The calculated concentration dependence $K(x)$ with a maximum near $x=0.3$ and a minimum near $x=0.8$ is in excellent agreement with experiment. This dependence is traced down to spin-orbital selection rules and the filling of electronic bands with increasing electronic concentration. At the optimal Co concentration, $K$ depends strongly on the tetragonality and doubles under a modest 3% increase of the $c/a$ ratio, suggesting that the magnetocrystalline anisotropy can be further enhanced using epitaxial or chemical strain.Comment: 4 pages + supplementary material, 6 figures. Accepted in Applied Physics Letter

The interlayer cohesive energy of graphite from thermal desorption of polyaromatic hydrocarbons

We have studied the interaction of polyaromatic hydrocarbons (PAHs) with the basal plane of graphite using thermal desorption spectroscopy. Desorption kinetics of benzene, naphthalene, coronene and ovalene at sub-monolayer coverages yield activation energies of 0.50 eV, 0.85 eV, 1.40 eV and 2.1 eV, respectively. Benzene and naphthalene follow simple first order desorption kinetics while coronene and ovalene exhibit fractional order kinetics owing to the stability of 2-D adsorbate islands up to the desorption temperature. Pre-exponential frequency factors are found to be in the range $10^{14}$-$10^{21} s^{-1}$ as obtained from both Falconer--Madix (isothermal desorption) analysis and Antoine's fit to vapour pressure data. The resulting binding energy per carbon atom of the PAH is $52\pm$5 meV and can be identified with the interlayer cohesive energy of graphite. The resulting cleavage energy of graphite is $61\pm5$~meV/atom which is considerably larger than previously reported experimental values.Comment: 8 pages, 4 figures, 2 table