2,091 research outputs found
What do cells actually want?
Genome-scale models require an objective function representing what an organism strives for. A method has been developed to infer this fundamental biological function from data.Please see related Research article: www.dx.doi.org/10.1186/s13059-016-0968-2
Factors Contributing to Successful Employment Outcomes for Hispanic Women Who Are Deaf: Utilization of Chi-Squared Automatic Interaction Detector and Logistic Regression Analysis
Hispanic women who are deaf constitute a heterogeneous group of individuals with varying vocational needs. To understand the unique needs of this population, it is important to analyze how consumer characteristics, presence of public supports, and type of services provided influence employment outcomes for Hispanic women who are deaf. The purpose of this study was to examine predictive factors of consumer characteristics, public supports, and patterns of service delivery related to employment among Hispanic women who are deaf utilizing the Rehabilitation Services Administration (RSA) case service report (RSA-911) for fiscal year 2009 (FY 2009). Exhaustive chi-squared automatic interaction detector (CHAID) analysis and binary logistic regression analysis were used to analyze the RSA-911 dataset. CHAID analysis allowed the extrapolation of four homogeneous subgroups (i.e., end groups) with similar characteristics influential in predicting successful versus unsuccessful employment outcomes. Results from the CHAID analysis revealed public support is the most salient factor in predicting employment outcomes for Hispanic women who are deaf. Resulting end groups from the CHAID analysis were used to inform the logistic regression analysis. The logistic regression analysis highlighted on-the-job supports, diagnosis and treatment of impairment, job placement services, rehabilitation technology, and assessment services rehabilitation services as the most influential services enhancing the probability of achieving a successful outcome
Tail amputation for treatment of osteomyelitis of the first and second coccygeal vertebrae in a cow
Diseases of the tail are common in cattle (3, 4). Infection or necrosis of the tail tip, injury of the coccygeal vertebrae resulting in tail paralysis (8, 12) as well as fracture or luxation of the coccygeal vertebrae(6) are some of the most common disorders. Congenital defects, diskospondylitis and tumours of the tail occur occasionally (5, 8). Tail fractures or luxations are usually the result of trauma, such as falls, excessive traction on the tail when moving a downer cow, excessive traction on a calf during assisted delivery, and mounting by other cows or heavy bulls (3, 13). Clinical signs depend on the severity of nerve damage and the location of the fracture. Fractures involving the second (S2), third and fourth sacral (S3 and S4) segments may affect the pudendal nerve, pelvic nerves and the tail nerve resulting in paralysis of the urinary bladder, anus and tail. Tail paralysis without other neurological deficits indicates damage to the coccygeal nerve (7). Diseases of the tail may be treated conservatively or by amputation cranial to the affected area. Tail amputation in cattle is a very controversial subject because in some countries, it is carried out prophylactically for management reasons without any medical indication (1, 9, 11). Prophylactic tail amputation is done 7–8 cm below the vulva in calves and 5–6 cm below the vulva in heifers and mature cows. The present case report describes complete amputation of the tail at the level of the sacrum in a cow with osteomye - litis of the first (C1) and second coccygeal (C2) vertebrae
Nanoplasmonic near-field synthesis
The temporal response of resonances in nanoplasmonic structures typically
converts an incoming few-cycle field into a much longer near-field at the spot
where non-linear physical phenomena including electron emission, recollision
and high-harmonic generation can take place. We show that for practically
useful structures pulse shaping of the incoming pulse can be used to synthesize
the plasmon-enhanced field and enable single-cycle driven nonlinear physical
phenomena. Our method is demonstrated for the generation of an isolated
attosecond pulse by plasmon-enhanced high harmonic generation. We furthermore
show that optimal control techniques can be used even if the response of the
plasmonic structure is not known a priori.Comment: 6 page
Hellbender (Cryptobranchus alleganiensis) gene flow within rivers of the Missouri Ozark highlands
Title from PDF of title page (University of Missouri--Columbia, viewed on September 9, 2013).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Thesis advisor: Dr. Lori S. EggertIncludes bibliographical references.M.A. University of Missouri-Columbia 2013.Dissertations, Academic -- University of Missouri--Columbia -- Biological sciences."May 2013"For species of conservation concern, effective management includes maintaining robust population sizes while monitoring and promoting genetic variability. For hellbenders (Cryptobranchus alleganiensis), an aquatic salamander species experiencing dramatic declines in population size, little is known about genetic variation at the within-river scale and whether habitat patches within rivers are genetically and/or demographically connected. Given that suitable habitat patches are isolated, and that hellbenders exhibit extreme site fidelity, gene flow may be restricted among these discrete habitat patches. Using several polymorphic microsatellite loci, I assessed the fine-scale genetic relationships between hellbenders occupying various habitat patches within a river. My results indicate that a substantial amount of gene flow is occurring between habitat patches, with no evidence to support genetic differentiation between patches. Since dispersal is the mechanism driving gene flow, it can be inferred from this data that hellbenders disperse, with dispersal hypothesized to occur during the larval and/or juvenile phase. Dispersal can occur in both males and females. However, the propensity for one sex to disperse more frequently than the other is driven by evolutionary forces and mating strategies. Using molecular techniques, I investigated differential dispersal between males and females in order to evaluate sex-biased dispersal in hellbenders. My results suggest that male and female hellbenders disperse, and that both sexes contribute to the observed levels of gene flow. Because hellbender populations are experiencing low juvenile recruitment in addition to the declines in population size, I compared heterozygosity levels in survived and dead offspring to evaluate how genetic diversity influences offspring survival. My results suggest that heterozygosity-fitness correlations would be an intriguing area of research to pursue in future studies, and may give further insight into causes for hellbender declines
Flow Measurement Options for Canal Turnouts
Volumetric record-keeping, billing, and allocations at irrigation district delivery points (turnouts) are the norm, rather than the exception for most California irrigation districts. However, many older districts are just beginning these efforts, and other districts are trying to improve existing hardware and procedures. Volumetric accounting with high accuracy and a reasonable price presents unique engineering challenges for irrigation districts because of the variety of existing structures and configurations at irrigation delivery points. Because it is likely that irrigation districts will attempt to utilize existing devices, or slightly modify them, there is a need for standardized installation and/or calibration. This paper discusses three efforts to adapt, improve, and/or calibrate existing technologies for flow rate and volumetric metering of canal turnouts
Nano-wires with surface disorder: Giant localization lengths and dynamical tunneling in the presence of directed chaos
We investigate electron quantum transport through nano-wires with one-sided
surface roughness in the presence of a perpendicular magnetic field.
Exponentially diverging localization lengths are found in the
quantum-to-classical crossover regime, controlled by tunneling between regular
and chaotic regions of the underlying mixed classical phase space. We show that
each regular mode possesses a well-defined mode-specific localization length.
We present analytic estimates of these mode localization lengths which agree
well with the numerical data. The coupling between regular and chaotic regions
can be determined by varying the length of the wire leading to intricate
structures in the transmission probabilities. We explain these structures
quantitatively by dynamical tunneling in the presence of directed chaos.Comment: 15 pages, 12 figure
Thermalization and Cooling of Plasmon-Exciton Polaritons: Towards Quantum Condensation
We present indications of thermalization and cooling of quasi-particles, a
precursor for quantum condensation, in a plasmonic nanoparticle array. We
investigate a periodic array of metallic nanorods covered by a polymer layer
doped with an organic dye at room temperature. Surface lattice resonances of
the array---hybridized plasmonic/photonic modes---couple strongly to excitons
in the dye, and bosonic quasi-particles which we call
plasmon-exciton-polaritons (PEPs) are formed. By increasing the PEP density
through optical pumping, we observe thermalization and cooling of the strongly
coupled PEP band in the light emission dispersion diagram. For increased
pumping, we observe saturation of the strong coupling and emission in a new
weakly coupled band, which again shows signatures of thermalization and
cooling.Comment: 8 pages, 5 figures including supplemental material. The newest
version includes new measurements and corrections to the interpretation of
the result
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