33,197 research outputs found
Initial stages of cavitation damage and erosion on copper and brass tested in a rotating disk device
In view of the differences in flow and experimental conditions, there has been a continuing debate as to whether or not the ultrasonic method of producing cavitation damage is similar to the damage occurring in cavitating flow systems, namely, venturi and rotating disk devices. In this paper, the progress of cavitation damage during incubation periods on polycrystalline copper and brass tested in a rotating disk device is presented. The results indicate several similarities and differences in the damage mechanism encountered in a rotating disk device (which simulates field rotary devices) and a magnetostriction apparatus. The macroscopic erosion appears similar to that in the vibratory device except for nonuniform erosion and apparent plastic flow during the initial damage phase
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Addressing the sugar, salt, and fat issue the science of food way.
Magnetic properties of strongly disordered electronic systems
We present a unified, global perspective on the magnetic properties of
strongly disordered electronic systems, with special emphasis on the case where
the ground state is metallic. We review the arguments for the instability of
the disordered Fermi liquid state towards the formation of local magnetic
moments, and argue that their singular low temperature thermodynamics are the
``quantum Griffiths'' precursors of the quantum phase transition to a metallic
spin glass; the local moment formation is therefore not directly related to the
metal-insulator transition. We also review the the mean-field theory of the
disordered Fermi liquid to metallic spin glass transition and describe the
separate regime of ``non-Fermi liquid'' behavior at higher temperatures near
the quantum critical point. The relationship to experimental results on doped
semiconductors and heavy-fermion compounds is noted.Comment: 25 pages; Contribution to the Royal Society Discussion Meeting on
"The Metal-Non Metal Transition in Macroscopic and Microscopic Systems",
March 5-6, 199
Electronic phase separation in the rare earth manganates, (La1-xLnx)0.7Ca0.3MnO3 (Ln = Nd, Gd and Y)
All the three series of manganates showsaturation magnetization
characteristic of ferromagnetism, with the ferromagnetic Tc decreasing with
increasing in x up to a critical value of x, xc (xc = 0.6, 0.3, 0.2
respectively for Nd, Gd, Y). For x > xc, the magnetic moments are considerably
smaller showing a small increase around TM, the value of TM decreasing slightly
with increase in x or decrease in . The ferromagnetic compositions (x xc)
show insulator-metal (IM) transitions, while the compositions with x > xc are
insulating. The magnetic and electrical resistivity behavior of these
manganates is consistent with the occurrence of phase separation in the
compositions around xc, corresponding to a critical average radius of the
A-site cation, , of 1.18 A. Both Tc and TIM increase linearly when < rA
> > or x xc as expected of a homogenous ferromagnetic phase. Both Tc
and TM decrease linearly with the A-site cation size disorder at the A-site as
measured by the variance s2. Thus, an increase in s2 favors the insulating AFM
state. Percolative conduction is observed in the compositions with > <
rAc >. Electron transport properties in the insulating regime for x > xc
conforms to the variable range hopping mechanism. More interestingly, when x >
xc, the real part of dielectric constant (e') reaches a high value (104-106) at
ordinary temperatures dropping to a very small (~500) value below a certain
temperature, the value of which decreases with decreasing frequency.Comment: 27 pages; 11 figures, Submitted to J.Phys:Condens Matte
The MIR Flickr Retrieval Evaluation Proposal Based on User Tags and Textual Passwords
In most well known image retrieval test sets, the imagery typically cannot be freely distributed or is not representative of a large community of users. In this paper we present a collection for the MIR community comprising 69,000 images from the Flickr website which are redistributable for research purposes and represent a real community of users both in the image content and image tags. We have extracted the tags and EXIF image meta data, and also make all of these publicly available. In addition we discuss several challenges for benchmarking retrieval and classification methods and applications
Dosing strategies for switching from oral risperidone to paliperidone palmitate: Effects on clinical outcomes.
IntroductionThere are currently no guidelines for switching patients from oral risperidone to paliperidone palmitate (Invega Sustenna®). Furthermore, the paliperidone long-acting injectable (LAI) package insert does not recommend bridging with oral antipsychotics, which may result in inadequate serum concentrations in patients on ≥4 mg/d risperidone.MethodsThis study evaluated the effects of suboptimal dosing and bridging in patients switched from oral risperidone to paliperidone LAI on hospitalization days, emergency department (ED)/mental health urgent care visits, and no-shows/cancellations to mental health appointments. Patients were categorized into optimal or suboptimal dosing based on their loading and maintenance paliperidone doses. Patients on risperidone ≥4 mg/d were categorized as bridged if they received risperidone for ≥7 days after the first paliperidone injection.ResultsThere were no significant differences in outcomes between optimally and suboptimally dosed patients. There were statistically significant reductions in hospitalization days in patients who were bridged compared with patients who were not bridged. There were statistically significant reductions in hospitalization days and ED/mental health urgent care visits after switching to paliperidone LAI.DiscussionThe results of this study indicate that bridging patients who are on ≥4 mg/d risperidone, when converting to paliperidone LAI, is associated with reductions in hospitalization days. However, more research is required to determine the optimal dose and duration of the bridge. The results also indicate that switching patients from oral risperidone to paliperidone LAI, even if the dose is suboptimal, is associated with reductions in hospitalization days and ED/mental health urgent care visits
Influence of Mo6+ on Dielectric properties of Copper Ferrites
Two series of copper ferrites are prepared using the chemical compositional formula Cu1.0-3y Fe2.0-2x Mox + yO4.0. They are calcinated at 750 C and sintered at 950C.When x =y = 0.0, the ε′ of the basic copper ferrite is probably due to electronic exchange interactions of copper and iron ions as Cu2+↔ Cu1+ and Fe3+↔ Fe2+. The observed value of dielectric constant (є′) decreases as a function of substituent concentration (x) up to x = 0.20 and for further values of ‘x’ it found to increase. In the case of ‘C’ (x = 0) series ferrites є′ decreases with substituent concentration (y) up to y = 0.04, later it found to increase. The dispersion of ac resistivity with frequency is observed indicating their strong dependence on frequency as in the case of dielectric behaviour. These results are explained with different possible mechanisms
Heterogeneity of monosomy 3 in fine needle aspiration biopsy of choroidal melanoma.
PurposeTo report on the heterogeneity of monosomy 3 in a fine needle aspiration biopsy obtained transsclerally from choroidal melanoma for prognosis.MethodsAll clinical records for patients who had been diagnosed with choroidal melanoma and underwent iodine-125 plaque brachytherapy with intraoperative transscleral fine needle aspiration biopsy from January 2005 to August 20, 2011, and who had a positive result for monosomy 3 according to fluorescence in situ hybridization as reported by clinical cytogenetics testing were collected. Patient age and sex, total number of cells evaluated and number of cells positive for monosomy 3, tumor size, and metastatic outcome were recorded for each patient.ResultsA positive result for monosomy 3 was reported in 93 patients who underwent transscleral fine needle aspiration biopsy. Two patients were lost to follow-up immediately post-operatively, and the remaining 91 patients were included in this study. The mean number of cells evaluated in the biopsy was 273 (range 28 to 520). The mean percentage of cells positive for monosomy 3 was 62.9% (range 4.7%-100%). The mean tumor height was 5.91 mm (range 1.99 to 10.85 mm). Larger tumors were associated with a higher percentage of cells positive for monosomy 3. During the average follow-up interval of 28.9 months (range 3-76 months), choroidal melanoma metastasis developed in 18 (20%) patients. Patients whose tumors had 1%-33% of cells positive for monosomy 3 had a significantly lower risk of metastasis-related death compared to patients whose tumors harbored a higher percentage of monosomy 3 (p = 0.04).ConclusionsCytogenetic heterogeneity of fluorescent in situ hybridization for monosomy 3 exists in a biopsy sample. Larger tumors were more likely to have a higher percentage of monosomy 3 positive cells in the sample. Furthermore, patients whose tumors had more than 33% of cells positive for monosomy 3 had a poorer prognosis than patients whose tumors had lower percentages of monosomy 3
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