3,714 research outputs found
Electric Chick Brooding Studies
Perhaps one of the most valuable lessons to be learned from a study of chick brooding is that good results can often be obtained in more ways than one. In carrying on work with electric brooders at the Nebraska Agricultural Experiment Station, special attention has been given to such factors as insulation and to other details of design which effect economy of operation and ease of construction. Low cost rather than cheapness has been the ideal. The work has been cooperative between the Agricultural Engineering Department and the Poultry Husbandry Department of the University of Nebraska
Electric Chick Brooding Studies
Perhaps one of the most valuable lessons to be learned from a study of chick brooding is that good results can often be obtained in more ways than one. In carrying on work with electric brooders at the Nebraska Agricultural Experiment Station, special attention has been given to such factors as insulation and to other details of design which effect economy of operation and ease of construction. Low cost rather than cheapness has been the ideal. The work has been cooperative between the Agricultural Engineering Department and the Poultry Husbandry Department of the University of Nebraska
A cancer cell-line titration series for evaluating somatic classification.
BackgroundAccurate detection of somatic single nucleotide variants and small insertions and deletions from DNA sequencing experiments of tumour-normal pairs is a challenging task. Tumour samples are often contaminated with normal cells confounding the available evidence for the somatic variants. Furthermore, tumours are heterogeneous so sub-clonal variants are observed at reduced allele frequencies. We present here a cell-line titration series dataset that can be used to evaluate somatic variant calling pipelines with the goal of reliably calling true somatic mutations at low allele frequencies.ResultsCell-line DNA was mixed with matched normal DNA at 8 different ratios to generate samples with known tumour cellularities, and exome sequenced on Illumina HiSeq to depths of >300Ă—. The data was processed with several different variant calling pipelines and verification experiments were performed to assay >1500 somatic variant candidates using Ion Torrent PGM as an orthogonal technology. By examining the variants called at varying cellularities and depths of coverage, we show that the best performing pipelines are able to maintain a high level of precision at any cellularity. In addition, we estimate the number of true somatic variants undetected as cellularity and coverage decrease.ConclusionsOur cell-line titration series dataset, along with the associated verification results, was effective for this evaluation and will serve as a valuable dataset for future somatic calling algorithm development. The data is available for further analysis at the European Genome-phenome Archive under accession number EGAS00001001016. Data access requires registration through the International Cancer Genome Consortium's Data Access Compliance Office (ICGC DACO)
Dynamics of Adsorbed Poly(Methyl Acrylate) and Poly(Methyl Methacrylate) on Silica
Deuterium NMR and modulated differential scanning calorimetry (MDSC) were used to probe the behavior of ultrathin adsorbed poly(methyl acrylate) (PMA). The spectra for the bulk methyl-labeled PMA-d3 were consistent with the motions of the polymer segments being spatially homogeneous. For the polymers adsorbed on silica, multicomponent line shapes were observed. The segmental mobility of the surface polymers increased with increased adsorbed amounts. In contrast to the behavior of the polymers in bulk, the adsorbed lower-molecular-mass PMA-d3 was less mobile than the adsorbed high-molecular-mass polymer. The presence of a polymer overlayer was sufficient to suppress the enhanced mobility of the more-mobile segments of the adsorbed (inner) polymer. MDSC studies on adsorbed poly(methyl methacrylate) showed that the glass-transition temperature of the thin polymer films increased and broadened compared to the behavior of the polymer in bulk. The presence of a motional gradient with the less-mobile segments near the solid-polymer interface and the more-mobile segments near the polymer-air interface was consistent with the experimental observations
Graduated Segmental Mobility in Polymer Layers on Silica
The behavior of thin polymer layers on oxide substrates has gotten a great deal of attention as the size of materials, and hence polymer films, has gotten smaller. Indeed, the properties of adsorbed polymers are such that they can be different from those of bulk polymers, especially when the films are very thin. A wide variety of studies have been made on adsorbed polymers and sometimes the results seem contradictory. One of the properties often measured in thin films is the apparent glasstransition temperature, Tg. In principle, many techniques are sensitive to phenomenological changes occurring around Tg and, therefore, can be compared to each other. For polymer thin films there are two surfaces (often different) to consider. For example, a thin polymer film on a solid substrate, such as silica, has a polymer-silica interface and a polymer-air interface. In principle, these two interfaces would be expected to have different properties. In addition, it is not always clear if either of these would dominate the properties measured. In this paper, we provide support for the existence of graduated segmental mobility in thin polymer films. As examples we cite the behavior observed from both deuterium NMR of poly(methyl acrylate)-d3 (PMA-d3) and modulated differential scanning calorimetry (MDSC) of poly(methyl methacrylate) (PMMA), both on silica powder. In Figure 1, we depict a surface with which the polymer has a favorable interaction. We propose that the segments at the polymer-air interface have enhanced mobility while those at the polymer-silica interfect have reduced mobility
EXCESSIVE TIBIAL ROTATION IS RESTORED AFTER ANATOMICAL DOUBLE BUNDLE ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION
Recent studies suggested that tibial rotaion was not restored after single bundle anterior cruciate ligament (ACL) reconstruction. This study aimed to determine if excessive tibial rotation would be restored by anatomical double bundle ACL reconstruction. Ten male subjects with unilateral ACL injury were prospectively assessed with a high demanding task before and after ACL reconstruction. Knee kinematics during pivoting movement was measured by a motion analysis system. The tibial rotation was reduced in the reconstructed knee after ACL reconstruction than the deficient knee (
The structure of Io's thermal corona and implications for atmospheric escape
We investigate the escape of species from Io's atmosphere using a steady-state model of Io's exospheric
corona and its interaction with the Io plasma torus. The corona is assumed to be spherically symmetric with
the radial density and compositional structure determined by the gas kinetic temperature, critical level radius,
and mixing ratios of the component species. Thermal and nonthermal escape rates are calculated and the
results compared with previously estimated torus and neutral cloud supply rates for O, S, Na, and K. Both
oxygen- and sulfur-dominated exospheres are considered. Atmospheric sputtering is found to be the major
escape mechanism for models in which the plasma flow reaches the critical level. However, such models
produce total mass-loading rates an order of magnitude larger than inferred values suggesting that either (1)
the structure of the thermal corona is significantly modified by the nonthermal interaction, or (2) substantial
plasma flow modification and deflection occurs in the corona at or above the critical level. Assuming that the
thermal model is a correct description of the corona, a comparison of these results with the observed near-Io
distribution of neutral Na and estimated source rates for the neutral Na "jets" suggests an extended Na
coronal component. Assuming that this component is part of the thermal exosphere, we find that the observations
are consistent with an O-dominated corona, an exospheric temperature ~1000 K, a 0.001 critical level
mixing ratio of Na, and a critical level radius ~1.5 R_(Io)
The 'At-risk mental state' for psychosis in adolescents : clinical presentation, transition and remission.
Despite increased efforts over the last decade to prospectively identify individuals at ultra-high risk of developing a psychotic illness, limited attention has been specifically directed towards adolescent populations (<18 years). In order to evaluate how those under 18 fulfilling the operationalised criteria for an At-Risk Mental State (ARMS) present and fare over time, we conducted an observational study. Participants (N = 30) generally reported a high degree of functional disability and frequent and distressing perceptual disturbance, mainly in the form of auditory hallucinations. Seventy percent (21/30) were found to fulfil the criteria for a co-morbid ICD-10 listed mental health disorder, with mood (affective; 13/30) disorders being most prevalent. Overall transition rates to psychosis were low at 24 months follow-up (2/28; 7.1 %) whilst many participants demonstrated a significant reduction in psychotic-like symptoms. The generalisation of these findings may be limited due to the small sample size and require replication in a larger sample
Novel experimental and software methods for image reconstruction and localization in capsule endoscopy
Background and study aims: Capsule endoscopy (CE) is invaluable for minimally invasive endoscopy of the gastrointestinal tract; however, several technological limitations remain including lack of reliable lesion localization. We present an approach to 3D reconstruction and localization using visual information from 2D CE images.
Patients and methods: Colored thumbtacks were secured in rows to the internal wall of a LifeLike bowel model. A PillCam SB3 was calibrated and navigated linearly through the lumen by a high-precision robotic arm. The motion estimation algorithm used data (light falling on the object, fraction of reflected light and surface geometry) from 2D CE images in the video sequence to achieve 3D reconstruction of the bowel model at various frames. The ORB-SLAM technique was used for 3D reconstruction and CE localization within the reconstructed model. This algorithm compared pairs of points between images for reconstruction and localization.
Results: As the capsule moved through the model bowel 42 to 66 video frames were obtained per pass. Mean absolute error in the estimated distance travelled by the CE was 4.1 ± 3.9 cm. Our algorithm was able to reconstruct the cylindrical shape of the model bowel with details of the attached thumbtacks. ORB-SLAM successfully reconstructed the bowel wall from simultaneous frames of the CE video. The “track” in the reconstruction corresponded well with the linear forwards-backwards movement of the capsule through the model lumen.
Conclusion: The reconstruction methods, detailed above, were able to achieve good quality reconstruction of the bowel model and localization of the capsule trajectory using information from the CE video and images alone
Domain Walls and Flux Tubes in N=2 SQCD: D-Brane Prototypes
This paper could have been entitled "D branes and strings from flesh and
blood." We study field theoretic prototypes of D branes/strings. To this end we
consider (2+1)-dimensional domain walls in (3+1)-dimensional N=2 SQCD with
SU(2) gauge group and two quark flavors in the fundamental representation. This
theory is perturbed by a small mass term of the adjoint matter which, in the
leading order in the mass parameter, does not break N=2 supersymmetry, and
reduces to a (generalized) Fayet-Iliopoulos term in the effective low-energy
N=2 SQED. We find 1/2 BPS-saturated domain wall solution interpolating between
two quark vacua at weak coupling, and show that this domain wall localizes a
U(1) gauge field. To make contact with the brane/string picture we consider the
Abrikosov-Nielsen-Olesen magnetic flux tube in one of two quark vacua and
demonstrate that it can end on the domain wall. We find an explicit 1/4
BPS-saturated solution for the wall/flux tube junction. We verify that the end
point of the flux tube on the wall plays the role of an electric charge in the
dual (2+1)-dimensional SQED living on the wall. Flow to N=1 theory is
discussed. Our results lead us to a conjecture regarding the notorious "missing
wall" in the solution of Kaplunovsky et al.Comment: 41 pages, 5 figures, Sect. 9.3 expanded, typos correcte
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