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BACKGROUND: Physician online ratings are ubiquitous and influential, but they also have their detractors. Given the lack of scientific survey methodology used in online ratings, some health systems have begun to publish their own internal patient-submitted ratings of physicians. OBJECTIVE: The purpose of this study was to compare online physician ratings with internal ratings from a large healthcare system. DESIGN: Retrospective cohort study comparing online ratings with internal ratings from a large healthcare system. SETTING: Kaiser Permanente, a large integrated healthcare delivery system. PARTICIPANTS: Physicians in the Southern California region of Kaiser Permanente, including all specialties with ambulatory clinic visits. MAIN MEASURES: The primary outcome measure was correlation between online physician ratings and internal ratings from the integrated healthcare delivery system. RESULTS: Of 5438 physicians who met inclusion and exclusion criteria, 4191 (77.1%) were rated both online and internally. The online ratings were based on a mean of 3.5 patient reviews, while the internal ratings were based on a mean of 119 survey returns. The overall correlation between the online and internal ratings was weak (Spearman’s rho .23), but increased with the number of reviews used to formulate each online rating. CONCLUSIONS: Physician online ratings did not correlate well with internal ratings from a large integrated healthcare delivery system, although the correlation increased with the number of reviews used to formulate each online rating. Given that many consumers are not aware of the statistical issues associated with small sample sizes, we would recommend that online rating websites refrain from displaying a physician’s rating until the sample size is sufficiently large (for example, at least 15 patient reviews). However, hospitals and health systems may be able to provide better information for patients by publishing the internal ratings of their physicians.

In this paper, we present recent results from bunch-shaping experiments using α-BBO crystal at the High Brightness Electron Beam Source Laboratory (HBESL). α-BBO crystals were used to shape the ultra-short laser pulse ( < 100fs) at HBESL to generate twin pulses at the cathode. The twin electron pulses were transported down the linac ( < 5 MeV) to a transverse deflecting mode cavity and the temporal profile recorded on the screen. The longitudinal time profile of the twin pulses show the difference between the effect of crystals and the longitudinal space charge effect. The electron beam was recorded for various position of the crystal and bunch charge.

Measurement of the Degree of Dissociation in Inductively Coupled Nitrogen Discharges by Using Optical Emission Actinometry and Mass Spectrometry Y. M. Shin, E. Y. Kim and T. H. Chung Department of Physics, Dong-A University, Busan 604-714 (Received 11 January 2008, in nal form 28 March 2008) The degree of dissociation is evaluated by using optical emission actinometry and mass spectrometry for inductively coupled nitrogen plasmas with pressures of 1 { 10 mTorr. The degree of dissociation is found to be between 1 % and 3.5 % and gradually increases with pressure and decreases slightly with power. The pressure dependence of the degree of dissociation measured by using optical emission actinometry and mass spectrometry exhibits a similar behavior. A physical explanation of these observations is given with a discussion of the particle balance and plasma properties, such as the electron density, the electron temperature and the electron energy probability function measured by using a Langmuir probe. PACS numbers: 52.25.Rv, 52.70.Kz, 52.20.Hv

Background This study aimed to investigate whether radiofrequency ablation (RFA) is an alternative to surgical resection for hepatocellular carcinoma (HCC) within the context of current guidelines. Methods This retrospective study included patients with normal portal pressure and serum bilirubin level who initially underwent liver resection or RFA for a single HCC of maximum size 3 cm. Between-group differences in cumulative rates of survival and recurrence specific for HCC were analysed in the entire cohort and in a propensity score-matched cohort. Results A total of 604 patients were enrolled, 273 in the liver resection group and 331 in the RFA group. The 5- and 10-year HCC-specific survival rates for the resection and RFA groups were 87·6 versus 82·1 per cent and 59·0 versus 61·2 per cent respectively (P = 0·214), whereas overall 5- and 10-year recurrence-free survival rates for the corresponding groups were 60·6 versus 39·4 per cent and 37·5 versus 25·1 per cent respectively (P < 0·001). In the propensity score-matched cohort (152 pairs), there were no differences in HCC-specific survival (hazard ratio (HR) 1·03 for RFAversus resection; P = 0·899), whereas recurrence-free survival again differed between the treatment groups (HR 1·75; P < 0·001). RFA was independently associated with poorer outcomes in terms of treatment-site recurrence-free survival (adjusted HR 1·66; P = 0·026), but not non-treatment-site recurrence-free survival (adjusted HR 1·15; P = 0·354). Conclusion Although RFA carries a higher risk of treatment-site recurrence than hepatic resection, it provides comparable overall survival in patients with a single small HCC without portal hypertension or a raised bilirubin level.

The Langmuir probe technique has some drawback in applying to electronegative plasma since it is difficult to interpret the probe I - V data. The positive ion flux to the probe is modified due to the presence of negative ions. In this study, an inductively coupled oxygen RF plasma is employed to perform the Langmuir probe measurement of the electronegative discharge. Plasma parameters are obtained from Langmuir probe measurement using two different methods which are based on electron energy distribution function (EEDF) integrals, and the method based on the fluid model for the modified ion flux, respectively. The EEDF is measured by a double differentiation of the I - V characteristics according to the Druyvesteyn formula. The electron densities estimated based on the two methods are compared. The EEDF integral method gives little higher values than the modified ion flux method. It is observed that at low pressure the EEDF is close to a Maxwellian. Generally, as the pressure increases, the distributions switch to bi-Maxwellian and to Druyvesteyn, and suggest some depletion of electrons with larger energies.

A new result for the transverse mu^+ polarization, P_T, in the decay K^+ --> pi^0 mu^+ nu has been obtained in the KEK E246 experiment. Combined with our earlier result, P_T = (-1.12 +- 2.17(stat) +- 0.90(syst))x10^{-3} and Im(\xi) = (-0.28 +- 0.69(stat) +- 0.30(syst))x10^{-2}, which are consistent with no T-violation., Comment: 5 pages, 2 figures, to be published in the Proceedings of the PANIC02, Osaka, Sept 30 - Oct 4, 2002

In the electrospinning process, polymer fibers with submicron-scale diameters are formed by subjecting a fluid jet to a high electric field. We report an experimental investigation of the electrically forced jet and its instabilities. The results are interpreted within the framework of a recently developed theory for electrified fluid jets. We find that the process can be described by a small set of operating parameters and summarized through the use of operating diagrams of electric field versus flow rate. In addition, the jet current is related to the net charge density and found to depend on the fluid properties, the applied electric field and the equipment configuration. The net charge density appears to be relatively insensitive to the flow rate, at least for high flow rates. The experiments reveal that a key process in the formation of submicron-scale solid fibers is a convective instability, the rapidly whipping jet. The dependence of this instability on electric field and flow rate, and the exponential nature of its growth rate are in accord with the theory.

The ratio of the $K^{+}\to \pi^{0} \mu^{+} \nu$ ($K_{\mu3}^+$) and $K^{+}\to \pi^{0} e^{+} \nu$ ($K_{e3}^+$) decay widths, $\Gamma(K_{\mu 3})/\Gamma(K_{e3})$, has been measured with stopped positive kaons. $K_{\mu3}^+$ and $K_{e3}^+$ samples containing 2.4$\times 10^4$ and 4.0$\times 10^4$ events, respectively, were analyzed. The $\Gamma(K_{\mu3})/\Gamma(K_{e3})$ ratio was obtained to be 0.671$\pm$0.007(stat.)$\pm$0.008(syst.) calculating the detector acceptance by a Monte Carlo simulation with the assumption of $\mu$-$e$ universality in $K_{l3}^+$ decay. The coefficient of the $q^2$ dependent term of the $f_0$ form factor was also determined to be $\lambda_0$=0.022$\pm$0.005(stat.)$\pm$0.004(syst.).

We grew vertically aligned carbon nanotubes (CNTs) using microwave plasma-enhanced (MPE) and thermal chemical-vapor deposition (CVD) and characterized their field emission properties. We observe that the flickering and instability in the field emission are due to the metal particles present on the field-emission array (FEA) surface, particularly from the MPECVD-grown samples. The existence of metal particles is an obstacle to obtaining reliable emission properties. The emission properties of the CNT–FEA are studied as a function of gas-exposure time with hydrogen, nitrogen, and oxygen gases. Gas exposures affected turn-on voltage, hysteresis, and the slope of Fowler–Nordheim plots. We observe that the saturation of emission currents is attributed to gas adsorbates present on the surface of the FEA. Oxygen exposures induce more severe degradation on the field-emission properties than nitrogen, whereas emission properties are improved by hydrogen gas exposures that clean the surface of emitters. In addition...

Hyperon-proton scattering is being studied at KEK in order to obtain a better understanding standing of the baryon-baryon interaction. A scintilating fiber (SCIFI) block detector has been used as a production target of hyperons as well as a target for hyperon scattering on hydrogen. The pilot experiment (E251) for Σ + p scattering has been completed, and the next experiment (E289) for Σ + p, Σ − p and Λp channels has finished its data taking and is now uder analysis.

Enhanced production of ΛΛ pairs, above the prediction of a two-step process model, is observed near threshold (around the masses of 2.23 – 2.26 GeV/c2) in the12C(K−,K+) reaction at PK− = 1.66GeV/c using a scintillating fiber target. The differential cross section for the ΛΛ production averaged over 2.3° ≤ $$K + ≤ 14.7° in the momentum region 0.95 ≤ pK + ≤ 1.3GeV/c was found to be 7.6 ± 1.3 μb/sr, and that for the enhancement approximately 3 μb/sr.

To evaluate the clinical utility of computed tomography (CT) and magnetic resonance imaging (MRI) in the diagnosis of peripheral cholangiocarcinoma of the liver, 11 patients with pathologically proven peripheral cholangiocarcinoma were examined with both CT and MRI. On CT scans in 10 cases, the tumors appeared as irregular, low-attenuation masses with a wide variation in heterogeneity. Contrast enhancement of the tumors was mild in nine cases and moderate in one case, at the periphery. Tumor was not identified in one case. On T1-weighted MRIs, the tumors showed low intensity in eight cases and isointensity in three cases. On T2-weighted images, the tumors showed high intensity in all 11 cases. Focal dilatation of the intrahepatic bile ducts around the tumor was seen in one case on MRIs and in four cases on CT scans. Portal vein invasion of the tumors was seen in one case, and lymphadenopathy was seen in four cases on both MRIs and CT scans. MRI was slightly superior to CT in detecting the tumors, was inferior to CT in delineating focal ductal dilatation around the tumors, and was equal to CT in assessing extent of the tumors.

Magnetic resonance (MR) imaging was performed on five tumors of three patients who had hepatic hemangiomas. Four tumors were given an intraarterial infusion of 3-8 ml of iodized oil, while one tumor was not. MR images were obtained at 2.0 or 0.5 T. A single spin echo sequence with TE of 30 ms and TR of 500 ms and a double echo sequence with TEs of 60 and 150 ms and TR of 2000 ms, were used to produce relatively T1-, T2-weighted, and heavily T2-weighted images, respectively. Follow-up MR imaging was done 1-5 months after infusion of iodized oil. On relatively T1-weighted images, hemangiomas showed iso- or hypointensity. On T2-weighted images, all tumors showed hyperintensity. However, on heavily T2-weighted images, tumors with iodized oil showed heterogeneous, slight hyperintensity, while tumors without iodized oil showed characteristic appearance of marked hyperintensity in hemangiomas. In hepatic cavernous hemangiomas with intraarterial infusion of iodized oil, familiarity with this unusual MR intensity of tumors on heavily T2-weighted images is useful to avoid the incorrect diagnosis and to reduce the frequency of inappropriate hepatic resection.

To design high power oversized Relativistic Backward Wave Oscillator (RBWO) which can generate GW-level Power in THz frequency, numerical studies such as finite difference time domain (FDTD) and particle in cell (PIC) were performed. 0.1GW at 0.1THz was estimated. The Oversized BWO which means relatively wide cross-section space (oversized) to decrease power density comparing with fundamental BWO is made up of slow wave structure (SWS) of rectangular type wall radius designed to generate wave on surface with strong interaction between electron beam and wave under intense fields at 500 kV-1.5kA, 100ns pulse in the relativistic range. In the meantime, the type of THz EM waves radiated antenna is COaxial Beam Rotating Antenna (COBRA). The antenna lens is designed to be matched with the W-band frequency and the thickness of lens is decided by theoretically calculation and results of numerical methods. On the basis of the results from numerical studies, it is designed and fabricated to generate radiated 0.1GW-0.1THz for 30ns, electromagnetic wave on the range of millimeter wave through these studies.

Background Miliary tuberculosis (TB) is an unusual cause of acute respiratory distress syndrome (ARDS). Objective To evaluate the clinical characteristics and outcomes of patients with ARDS caused by miliary TB admitted to the intensive care unit (ICU). Design A total of 67 patients were enrolled during the period 1999-2008. Results The median age of the patients was 56 years (range 17-81), 19 (28.4%) were aged >71 years, and 38 (56.7%) were male. All-cause mortality in the ICU and hospital were respectively 58.2% and 61.2%. Of the total number of enrolled patients, 49 (73.1%) were prescribed anti-tuberculosis medication within 3 days of hospital admission. On the day of ARDS diagnosis (10.0 ± 3.7 vs. 7.4 ± 3.5, P = 0.005), non-survivors had a significantly higher Sequential Organ Failure Assessment (SOFA) score than survivors. Multivariate analysis showed that SOFA score on the day of ARDS diagnosis was a significant predictor of survival (OR 0.809, 95%CI 0.691-0.946, P = 0.008). It was difficult to determine the efficacy of systemic corticosteroids on patient survival. Conclusion ARDS caused by miliary TB was associated with a high in-hospital mortality rate, with SOFA score on the day of ARDS diagnosis being a valuable prognostic indicator.

Polymeric fibers with diameters in the range from 50 nm to 5 μm are produced by accelerating a fluid jet in an electric field, in a process known as “electrospinning.” Here we show that an essential element of the process is a fluid instability, the rapidly whipping jet. The phenomena responsible for the onset of whipping are revealed by a linear instability analysis that describes the jet behavior in terms of known fluid properties and operating conditions. The behavior of two competing instabilities, the Rayleigh mode and the axisymmetric conducting mode, is also described. The results are summarized using operating diagrams, delineating regimes of operation in electrospinning, which are in good agreement with experimental observations.

We report a thermionic Pierce electron gun, which has been designed, developed and experimentally tested for getting desired performance for W-band LIGA fabricated devices like folded waveguide backward-wave oscillator (FWBWO). This gun has used thermionic dispenser cathode of 1.6 mm button diameter with corresponding cathode emission loading around 2.5 A/cm2 . It is delivering 50 mA beam current at 12 kV beam voltage with 0.36 mm beam waist radius. The current density of beam is estimated at the beam waist position.

A search for T-violating transverse muon polarization (P(T)) in the K+-->pi(0)mu(+)nu decay was performed using kaon decays at rest. A new improved value P(T)=-0.0017+/-0.0023(stat)+/-0.0011(syst) was obtained giving an upper limit |P(T)

The detector built at KEK to search for T-violating transverse muon polarization in K+ --> pi0 mu+ nu (Kmu3) decay of stopped kaons is described. Sensitivity to the transverse polarization component is obtained from reconstruction of the decay plane by tracking the mu+ through a toroidal spectrometer and detecting the pi0 in a segmented CsI(Tl) photon calorimeter. The muon polarization was obtained from the decay positron asymmetry of muons stopped in a polarimeter. The detector included features which minimized systematic errors while maintaining high acceptance., Comment: 56 pages, 30 figures, submitted to NIM

Until recently, MRI has not been considered to be suitable for the evaluation of the small intestine due to artifacts associated with bowel peristalsis or respiration. However, recent advances of MR techniques enable the acquisition of clear images of the small intestine. Therefore, the purpose of this article is to review the details for the application of MRI in patients with small intestinal diseases. This article discusses bowel preparation and oral contrast agents as well as MR techniques and pulse sequences. Thereafter, the usefulness of MRI for the lesions in the peritoneal cavity or in the gastrointestinal tract are discussed. Small intestinal lesions are categorized into inflammatory, neoplastic, ischemic, and obstructive bowel diseases. In conclusion, MRI can be used as an alternate modality of choice for imaging various diseases of the small intestine.

The new low energy hyperon‐nucleon scattering data have been long waited since the low statistics data were obtained in 1960s from the bubble chamber experiments. At KEK, an experiment to measure ∑++p elastic scattering has been performed utilizing the novel scintillating fiber technology. In this report we present the status of the analysis on this experiment and the preliminary total cross section data of ∑++p scattering.

Gliomatosis cerebri is a diffuse infiltrative glial neoplasm frequently involving both cerebral hemispheres. Diagnosis and evaluation of its extent with CT are known to be difficult. The purpose of this study was to compare the MR and CT findings in gliomatosis cerebri.MR images of nine patients were reviewed retrospectively and compared with CT scans. Pathology was determined by open or stereotaxic biopsy. The MR images included sagittal T1-weighted, axial proton density-weighted, and T2-weighted images. Contrast material was administered in seven patients. Unenhanced and enhanced CT scans were obtained in eight patients.On proton density-weighted and T2-weighted MR images, the most common findings were poorly defined bilateral areas of diffuse high signal intensity in the cerebral hemisphere. On T1-weighted images, the lesions were isointense to hypointense compared with normal brain. Enhanced T1-weighted images showed focal parenchymal enhancement in three patients and meningeal enhancement in one. On CT scans, the lesions showed poorly defined areas of subtle low density or isodensity, and appeared much smaller than those on T2-weighted MR images. Enhancement was seen in only one case. The extent of disease was evaluated much better on T2-weighted MR images than on T1-weighted MR images and CT scans.In gliomatosis cerebri, MR imaging is more sensitive than CT for detecting lesions and shows the extent of disease better than CT does. Accordingly, MR imaging should be used as a primary imaging study in the evaluation of gliomatosis cerebri.

Energy spectra of charged particles produced by electron and bremsstrahlung bombardment of 6Li and 7Li were measured by means of a magnetic spectrometer and solid-state detectors. Assuming that all transitions leave the residual nucleus in the ground state, the photonuclear cross sections were obtained using both bremsstrahlung and E1 virtual photon spectra. Comparison of the present real and virtual photon results is made with those of previous experiments.

Previous work on obtaining beam centroid position information using a beam excited resonant cavity with two orthogonal TM110 modes was extended to a higher harmonic cavity. The cavity operated at a frequency of 3220 MHz, the fourth harmonic of the accelerator frequency, and was fine tuned by using the frequency shift caused by varying the size of the beam hole. As predicted by beam-cavity interaction theory, the cavity output signal was shown to be proportional both to the square of the beam centroid displacement and to the square of beam current, and to be well correlated with position information obtained by self-powered ?-ray detectors. A crystal and a singly balanced mixer were used to process this signal to give information of both magnitude and sign of the beam position. The cavity was used to observe the effects on beam position when slow (0.01 Hz) sinusoidal disturbances were applied to three accelerator parameters: forward power, frequency and phase. Corresponding changes in the beam position have been found. The preliminary results of an automatic beam centering control show that slow disturbances on beam position can be corrected by driving a steering magnet with the cavity signals.

The results of measurements on the 3He(e,e′d)1H reaction are presented. No evidence for structure in 3He has been observed over the energy region 16–27 MeV.

The electrodisintegration cross sections, 16O(e,α0)12C,e′ and 20Ne(e,α0)16O,e′, have been measured and, by using virtual photon analysis, a comparison with photodisintegration experiments has been made. Satisfactory agreement with earlier 12C(α,γ0)16O experiments was found and the 20Ne(γ,α0)16O reaction reveals several pronounced resonances.

Tritons resulting from the electrodisintegration of 7Li have been measured at 90° for an incident electron energy of 23.8 MeV over an energy range which ensured that only tritons emitted in the two-body channel were detected. The electrodisintegration cross sections were converted to equivalent photodisintegration data and compared to earlier results. Large discrepancies are observed. It is found that the (γ,3H) channel contributes appreciably to the electric dipole sum rule for 7Li.

Gamma rays and electrons have been used for the removal of SO2 which may be a major noxious component in combustion gases of fuel oils from industrial plants. It was found, as expected, that SO2 can be removed by irradiation, and electrons are much more efficient than gamma rays.

All languages appear to have one or more ‘generalised action verbs’ (Van Valin & LaPolla 1997), which, like English do in Who did this?, are used as ‘pro-verbs’ in contexts where the nature of an event is unknown or left unspecified. It has been claimed in the literature that the concept ‘DO’ is universal, and moreover, that it is universally linked to the notion of agency. This assumption is also at the heart of proposals to use DO in the semantic decomposition of verbs, pioneered by Dowty (1979: 110-125). Foley & Van Valin (1984: 47-53) and Van Valin & LaPolla (1997: 102-129) even use two kinds of ‘do’ operators, one to represent activities, and one to represent agency. This paper, through comparing the semantic range of generalised action verbs in a sample of eight unrelated languages, demonstrates that agentivity is not a necessary correlate of generalised action verbs, even though this may appear to be the case if only European languages are considered. In some languages, generalised action verbs verbs function as translation equivalents of quotative verbs (‘say’), verbalisers with ideophonic expressons (‘go pop’), eventive verbs (‘happen’), and even inchoative verbs (‘become’). It is argued that the concept of internal causation is as important in central for the range of uses of generalised action verbs as the concept of agentivity. The semantic range of these verbs thus includes a number of concepts for which primitives that are supposedly semantically distinct from DO have been introduced in the literature, e.g. CAUSE and BECOME in the Foley/Van Valin/LaPolla framework, and HAPPEN, SAY, and FEEL, which are claimed to be semantic primitives in Wierzbicka’s ‘Natural Semantic Metalanguage’ framework (cf. Wierzbicka 1994). The cross-linguistic data suggest, however, that a semantic map approach is more suitable for the description of the potential semantic range of generalised action verbs than a decompositional approach with discrete semantic components. A semantic map for generalised action verbs is proposed in the final section of the paper.

Measurements of the vector analyzing power iT11 in πd elastic scattering at 49 MeV have been performed using a dynamically polarized target and a magnetic spectrometer. Data at seven π+ laboratory scattering angles between 50° and 130° were taken together with a complementary measurement at 60° for π-d elastic scattering. In general, we find agreement with models that include the πN P11 amplitude and disagreement with models that exclude or suppress it.

Measurements of the vector analyzing power iT11 in π+d elastic scattering at 50 MeV have been made at pion laboratory scattering angles between 60° and 130° using a dynamically polarized target and a magnetic spectrometer. In contrast to measurements of spin observables at higher energies, we find agreement with models that include the πN P11 amplitude and disagreement with models that exclude or suppress it.