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Environmental sampling to assess the bioburden of Mycobacterium avium subspecies paratuberculosis in drylot pens on California dairies.
Mycobacterium avium subspecies paratuberculosis (MAP) is a bacterium that can cause substantial economic losses in infected dairy herds due to reduced milk production and increased cow-replacement costs. In order to control MAP in dairies with drylot pens, a standardized environmental sampling protocol to quantify MAP in fecal slurry was developed based on an existing protocol for freestall pens. Specifically, following a 24 h hold of the flush, a grab sample of approximately 10 ml of fecal slurry was collected every 1 m along the flush lane of the drylot pens, avoiding individual cow fecal pats. To determine the reliability and repatability of the new environmental sampling protocol for estimation of MAP bioburden at the pen level, two collectors simultaneously collected fecal slurry samples every day for 3 days from six drylot cow pens on two Central California dairies. During the study period no cow movement between pens was allowed with the exception of sick cows. The study herds had MAP seroprevalence of 5.8% and 3.2%, respectively, based on whole pen serum ELISA results. Variance components models for quantitative real-time PCR (qPCR) results showed samples collected from different pens on different dairies accounted for greater variablitiy in MAP concentration (65%), while samples collected by different collectors had the least variability (0.1%). In contrast, variability in MAP concentration in environmental samples collected on different days had 25% variability. The intraclass correlation coefficient showed high reliability (93%) of environmental sampling simultaneously by different collectors. In contrast, the reliability of environmental sampling at different days was 65%, which was similar to the reliability for sampling by different collectors on different days. Investigators can expect high reliability when employing the new environmental sampling protocol along with qPCR testing of environmental samples from drylot pens
CHANGES IN UPPER EXTREMITY MUSCLE ACTIVATION IN THE PRESENCE OF STRESS
This study examined the muscle activity of the flexor digitorum (FD), biceps brachii (BB), triceps brachii (TB), and pectoralis major (PM) during the American football throw with and without conditions of stress. Male subjects (n=5) with either football or baseball experience threw footballs at targets with distances of 12.91 m, 18.29 m, and 28.91 m. Throwing arm muscle activity was assessed via electromyography. Results showed that the flexor digitorum muscle had lower muscle activation for the stress condition at the long distance along with the pectoral muscle at the middle distance
IR Kuiper Belt Constraints
We compute the temperature and IR signal of particles of radius and
albedo at heliocentric distance , taking into account the
emissivity effect, and give an interpolating formula for the result. We compare
with analyses of COBE DIRBE data by others (including recent detection of the
cosmic IR background) for various values of heliocentric distance, ,
particle radius, , and particle albedo, . We then apply these
results to a recently-developed picture of the Kuiper belt as a two-sector disk
with a nearby, low-density sector (40<R<50-90 AU) and a more distant sector
with a higher density. We consider the case in which passage through a
molecular cloud essentially cleans the Solar System of dust. We apply a simple
model of dust production by comet collisions and removal by the
Poynting-Robertson effect to find limits on total and dust masses in the near
and far sectors as a function of time since such a passage. Finally we compare
Kuiper belt IR spectra for various parameter values.Comment: 34 pages, LaTeX, uses aasms4.sty, 11 PostScript figures not embedded.
A number of substantive comments by a particularly thoughtful referee have
been addresse
Ideally embedded space-times
Due to the growing interest in embeddings of space-time in higher-dimensional
spaces we consider a specific type of embedding. After proving an inequality
between intrinsically defined curvature invariants and the squared mean
curvature, we extend the notion of ideal embeddings from Riemannian geometry to
the indefinite case. Ideal embeddings are such that the embedded manifold
receives the least amount of tension from the surrounding space. Then it is
shown that the de Sitter spaces, a Robertson-Walker space-time and some
anisotropic perfect fluid metrics can be ideally embedded in a five-dimensional
pseudo-Euclidean space.Comment: layout changed and typos corrected; uses revtex
Vertical Resolution of a Seismic Survey in Stratigraphic Sequences less than 100 m Deep in Southeastern Kansas
A 400-m long, 12-fold high-resolution common depth point (CDP) reflection seismic profile was acquired across shallow converging Pennsylvanian strata in the Independence area of southeastern Kansas. One of the principal objectives was to determine practical vertical resolution limits in an excellent shallow seismic-data area with borehole control. The dominant frequency of the CDP stacked data is in excess of 150 Hz based on peak-to-peak measurements. Interference phenomena observed on stacked seismic data incorporated with models derived from log and drill-hole information suggest a practical vertical resolution limit of about 7 m, or one-third of the dominant wavelength. The data suggest conventional rules of thumb describing resolution potential are not accurate when reflectors on shallow, narrow bandwidth data converge rapidly across horizontal distances less than the Fresnel Zone
Selective Photothermolysis of Cutaneous Pigmentation by Q-switched Nd: YAG Laser Pulses at 1064, 532. and 355nm
Exposure of skin to nanosecond-domain laser pulses affects the pigmentary system by a process called selective photothermolysis, in which melanosomes and pigmented cells are preferentially altered. Due to the broad absorption spectrum of melanin, this effect may occur with wavelengths that penetrate to vastly different depths within tissue, potentially producing different biologic responses. The effects of single near-ultraviolet (355nm), visible (532nm), and near infrared (1064nm) pulses of 10–12nsec duration were determined in guinea pig skin using gross, histologic, and electron microscopic observations. Threshold response in pigmented skin was a transient immediate ash-white discoloration, requiring 0.11, 0.20 and 1.0J/cm2, at 355, 532, and 1064 nm, respectively. At each wavelength, melanosomes were reputed within keratinocytes and melanocytes, with cytoplasmic and nuclear alterations. Delayed epidermal depigmentation occurred, followed by gradual repigmentation. Deep follicular cells were altered only at 532 and 1064 nm, which produced permanent leukotrichia. The action spectrum for threshold response was consistent with mechanisms implied by selective photothermolysis. These data may be useful for consideration of treatment for cutaneous pigmentation abnormalities or unwanted follicular pigmentation, or both
Comparison of the subunit and primary structures of the pyruvate kinases from rabbit and sturgeon muscles
Case Report Q Fever with Unusual Exposure History: A Classic Presentation of a Commonly Misdiagnosed Disease
We describe the case of a man presumptively diagnosed and treated for Rocky Mountain spotted fever following exposure to multiple ticks while riding horses. The laboratory testing of acute and convalescent serum specimens led to laboratory confirmation of acute Q fever as the etiology. This case represents a potential tickborne transmission of Coxiella burnetii and highlights the importance of considering Q fever as a possible diagnosis following tick exposures
Embeddings in Spacetimes Sourced by Scalar Fields
The extension of the Campbell-Magaard embedding theorem to general relativity
with minimally-coupled scalar fields is formulated and proven. The result is
applied to the case of a self-interacting scalar field for which new embeddings
are found, and to Brans-Dicke theory. The relationship between Campbell-Magaard
theorem and the general relativity, Cauchy and initial value problems is
outlined.Comment: RevTEX (11 pages)/ To appear in the Journal of Mathematical Physic
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