1,268 research outputs found
Crushed Stone Aggregate Resources of Indiana
Indiana Geological Survey Bulletin 42-HMineral aggregate is an aggregation of mineral material, such as
crushed rock, expanded shale, perlite, sand and gravel, shells, or slag.
It is sometimes bound with such material as cement or asphalt or is
sometimes not bound for use as filter stone, flux stone, railroad
ballast, riprap, or road metal. Crushed limestone and dolomite, sand
and gravel, slag, perlite, and expanded shale are the main natural and
fabricated aggregates currently used in Indiana. Some aggregate, such
as sand and gravel, requires little or no processing and can be used
almost as it is mined, but rock must be crushed and sorted into
various desired sizes before it can be used. Many types of rocks can
be used for crushed stone aggregate, but limestone and dolomite are
used exclusively in Indiana (pl. 1). In this report crushed stone is
synonymous with crushed limestone and dolomite.
Each type of aggregate has a distinct advantage with respect to
cost and availability or to a specific use for which one type is more
suited than another. The advantages of crushed limestone and
dolomite are that they can be crushed and sized to meet most specifications,
the materials are clean and angular and bind well with
cementing mixtures, a uniform lithologic composition can be maintained
with little or no selective quarrying in many areas, and they
are available at low cost in most counties in Indiana. Crushed stone
is one of Indiana’s most important mineral commodities, ranking
third in annual value behind coal and cement. During 1969 crushed
stone production in Indiana totaled 25, 516,000 tons and was valued
at $34,418,000.Indiana Department of Natural Resource
Verifying Quantum Phase Estimation (QPE) using Prove-It
The general-purpose interactive theorem-proving assistant called Prove-It was
used to verify the Quantum Phase Estimation (QPE) algorithm, specifically
claims about its outcome probabilities. Prove-It is unique in its ability to
express sophisticated mathematical statements, including statements about
quantum circuits, integrated firmly within its formal theorem-proving
framework. We demonstrate our ability to follow a textbook proof to produce a
formally certified proof, highlighting useful automation features to fill in
obvious steps and make formal proving nearly as straightforward as informal
theorem proving. Finally, we make comparisons with formal theorem-proving in
other systems where similar claims about QPE have been proven.Comment: 28 pages, 18 figures, 5 tables. Prove-It theorem-proving results
available at http://pyproveit.org/ and Prove-It code available at
https://github.com/PyProveIt/Prove-I
Effects of soil-moisture content on shallow seismic data
This is the publisher's version, also available electronically from "http://library.seg.org".Repeated shallow‐seismic experiments were conducted at a site on days with different near‐surface moisture conditions in unconsolidated material. Experimental field parameters remained constant to ensure comparability of results. Variations in the seismic data are attributed to the changes in soil‐moisture content of the unconsolidated material. Higher amplitudes of reflections and refractions were obtained under wetter near‐surface conditions. An increase in amplitude of 21 dB in the 100–300 Hz frequency range was observed when the moisture content increased from 18% to 36% in the upper 0.15 m (0.5 ft) of the subsurface. In the time‐domain records, highly saturated soil conditions caused large‐amplitude ringy wavelets that interfered with and degraded the appearance of some of the reflection information in the raw field data. This may indicate that an intermediate near‐surface moisture content is most conducive to the recording of high‐quality shallow‐seismic reflection data at this site. This study illustrates the drastic changes that can occur in shallow‐seismic data due to variations in near‐surface moisture conditions. These conditions may need to be considered to optimize the acquisition timing and parameters prior to collection of data
Conditional disruption of rictor demonstrates a direct requirement for mTORC2 in skin tumor development and continued growth of established tumors
These studies show for the first time that mTORC2 is essential for skin tumor development and maintenance of established tumors, but is dispensable for normal keratinocyte proliferation. They further suggest that mTORC2 controls pro-survival pathways in vitro and in tumor
Tick Haller\u27s Organ, a New Paradigm for Arthropod Olfaction: How Ticks Differ from Insects
Ticks are the vector of many human and animal diseases; and host detection is critical to this process. Ticks have a unique sensory structure located exclusively on the 1st pairs of legs; the fore-tarsal Haller\u27s organ, not found in any other animals, presumed to function like the insect antennae in chemosensation but morphologically very different. The mechanism of tick chemoreception is unknown. Utilizing next-generation sequencing and comparative transcriptomics between the 1st and 4th legs (the latter without the Haller\u27s organ), we characterized 1st leg specific and putative Haller\u27s organ specific transcripts from adult American dog ticks, Dermacentor variabilis. The analysis suggested that the Haller\u27s organ is involved in olfaction, not gustation. No known odorant binding proteins like those found in insects, chemosensory lipocalins or typical insect olfactory mechanisms were identified; with the transcriptomic data only supporting a possible olfactory G-protein coupled receptor (GPCR) signal cascade unique to the Haller\u27s organ. Each component of the olfactory GPCR signal cascade was identified and characterized. The expression of GPCR, Gαo and β-arrestin transcripts identified exclusively in the 1st leg transcriptome, and putatively Haller\u27s organ specific, were examined in unfed and blood-fed adult female and male D. variabilis. Blood feeding to repletion in adult females down-regulated the expression of all three chemosensory transcripts in females but not in males; consistent with differences in post-feeding tick behavior between sexes and an expected reduced chemosensory function in females as they leave the host. Data are presented for the first time of the potential hormonal regulation of tick chemosensation; behavioral assays confirmed the role of the Haller\u27s organ in N,N-diethyl-meta-toluamide (DEET) repellency but showed no role for the Haller\u27s organ in host attachment. Further research is needed to understand the potential role of the GPCR cascade in olfaction
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