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1.
Curr Oncol ; 24(4): e285-e289, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28874899

RESUMEN

PURPOSE: We evaluated the efficacy and toxicity of accelerated hypofractionated radiotherapy (ahypof-rt) for central-type small lung tumours. METHODS: Between November 2006 and January 2015, 40 patients with central-type small lung tumours underwent ahypof-rt delivered using 10 MV X-rays and a coplanar 3-field technique. The number of fractions ranged from 24 to 28, with a fraction size of 2.5-3 Gy. A total dose of 69-75 Gy to the isocentre of the planning target volume was administered to each patient. Cumulative survival and local control rates were calculated using the Kaplan-Meier method. RESULTS: The 27 men and 13 women enrolled in the study had a median age of 79 years (range: 60-87 years). The tumour stage was T1a in 9 patients, T1b in 17 patients, and T2a in 14 patients, with a median size of 26.5 cm (range: 11-49 cm). The median follow-up period was 23 months. A complete response was achieved in 3 patients (7.5%), and a partial response, in 17 patients (42.5%). The overall 2-year and 3-year local control rates were 87.3% and 81.8% respectively; the 2-year and 3-year overall survival rates were 78.9% and 66.7% respectively. Grade 3 pneumonitis occurred in 3 patients; no other severe adverse events (≥grade 3) were observed in any patient. CONCLUSIONS: Accelerated hypofractionated radiotherapy using a fraction size of 2.5-3 Gy was highly safe and can be a more effective treatment option than conventional radiotherapy for patients with central-type small lung tumours.

2.
Environ Sci Pollut Res Int ; 21(5): 3873-9, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24288059

RESUMEN

Carbon monoxide (CO) is of great interest as a restriction factor for pollutants related to incomplete combustions. This study attempted to evaluate CO emission in East China using the analytical Bayesian inverse method and observations at Mount Hua in springtime. The mixing ratio of CO at the receptor was calculated using 5-day source-receptor relationship (SRR) simulated by a Lagrangian Particle Dispersion Model (FLEXPART) and CO emission flux. The stability of the inversion solution was evaluated on the basis of repeated random sampling simulations. The inversion results demonstrated that there were two city cluster regions (the Beijing-Tianjin-Hebei region and the low reaches of the Yangtze River Delta) where the difference between a priori (Intercontinental Chemical Transport Experiment-Phase B, INTEX-B) and a posteriori was statistically significant and the a priori might underestimate the CO emission flux by 37 %. A correction factor (a posteriori/a priori) of 1.26 was suggested for CO emission in China in spring. The spatial distribution and magnitude of the CO emission flux were comparable to the latest regional emission inventory in Asia (REAS2.0). Nevertheless, further evaluation is still necessary in view of the larger uncertainties for both the analytical inversion and the bottom-up statistical approaches.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monóxido de Carbono/análisis , Modelos Teóricos , Altitud , Teorema de Bayes , China , Monitoreo del Ambiente/métodos , Monitoreo del Ambiente/estadística & datos numéricos , Estaciones del Año
3.
Kyobu Geka ; 65(5): 347-52; discuaaion 352-6, 2012 May.
Artículo en Japonés | MEDLINE | ID: mdl-22569490

RESUMEN

BACKGROUND: Aortic root replacement (ARR) combined with aortic arch replacement (AAR) is an invasive procedure even in elective cases. Nevertheless, such combined operations are often mandatory in acute type A aortic dissection. We examined whether emergency operation might have further incremental risks compared with elective surgery in this type of operations. METHODS: Forty-six cases of ARR combined with AAR were divided into 2 groups, the emergency (EM) group and the elective (EL) group. The EM group consisted of 10 cases of acute type A aortic dissection, whereas the EL group of 36:23 of chronic aortic dissection and 13 of true aneurysm. RESULTS: There were no statistical differences between the 2 groups in the durations of aortic crossclamp, selective cerebral perfusion and cardiopulmonary bypass. The incidences in the EM and EL groups were as follows:in-hospital death; 0 vs 3( 8%), respiratory failure; 4 (40%) vs 14 (39%), renal failure; 0 vs 6 (17%), IABP requirement; 1 (10%) vs 3 (8%), and cerebral infarction; 0 vs 1 (3%), respectively. CONCLUSION: Early surgical results of emergency ARR combined with AAR were almost equal to those in elective surgery.


Asunto(s)
Aorta Torácica/cirugía , Aneurisma de la Aorta/cirugía , Disección Aórtica/cirugía , Procedimientos Quirúrgicos Electivos , Urgencias Médicas , Humanos
4.
Phys Rev Lett ; 104(13): 136801, 2010 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-20481900

RESUMEN

We investigated the electron transport property of the InGaAs/GaAs double quantum dots, the electron g factors of which are different from each other. We found that in a magnetic field, the resonant tunneling is suppressed even if one of the Zeeman sublevels is aligned. This is because the other misaligned Zeeman sublevels limit the total current. A finite broadening of the misaligned sublevel partially relieves this bottleneck effect, and the maximum current is reached when interdot detuning is half the Zeeman energy difference.

5.
Fortschr Neurol Psychiatr ; 76(4): 232-5, 2008 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-18393135

RESUMEN

The social situation of the mentally disabled in Japan was characterized by living in closed sanatoriums with only few possibilities to participate in normal social life until the 80 (ths) of the last century. However, important improvements regarding the social integration have been achieved over the last years. Revisions of existing laws, private initiatives like working places for the disabled and other community associated facilities have been of special importance and have led to a better integration of the disabled in the normal social life. In the report examples of successful initiatives are described. The paid labour in the working facilities seems to be of high importance as they permit an economic and social autonomy and a higher self-respect.


Asunto(s)
Trastornos Mentales/psicología , Humanos , Japón/epidemiología , Trastornos Mentales/epidemiología , Trastornos Mentales/rehabilitación , Conducta Social , Medio Social
6.
J Environ Monit ; 9(11): 1183-93, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17968444

RESUMEN

An international exercise to directly assess consistency of standards for ground-level ozone in East Asia was conducted as part of the East Asian Regional Experiment 2005 (EAREX 2005) in the framework of the Atmospheric Brown Clouds (ABC) project. Ten organizations collaboratively participated in the intercomparison. Four groups representing Japan, Korea, Hong Kong, and Taiwan made comparisons at the Gosan super observatory, Jeju Island, Korea, in March 2005, with ozone instruments calibrated to their national standards, and four Japanese groups made off-site comparisons with laboratory-level standards. All comparisons generally indicated good agreement with the standard reference photometer (SRP) 35, built by the National Institute of Standards and Technology (USA) and maintained by the National Institute for Environmental Studies (Japan). The assessment was expanded to measurement networks contributing to the World Meteorological Organization's Global Atmospheric Watch (WMO/GAW) program as part of off-site comparisons, and excellent agreement was achieved. These efforts contribute to propagating traceability of the national metrology standards among the atmospheric science community, to ensuring comparability of the existing ozone measurements, and to establishing an integrated network of air quality monitoring in Asia.


Asunto(s)
Ozono/análisis , Asia , Cooperación Internacional , Ozono/normas , Control de Calidad , Estándares de Referencia , Espectrofotometría Ultravioleta
7.
Phys Rev Lett ; 99(9): 095301, 2007 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-17931016

RESUMEN

The viscosity is measured for a Fermi liquid, a dilute 3He-4He mixture, under extremely high magnetic field/temperature conditions (Bor=1.5 mK). The spin-splitting energy microB is substantially greater than the Fermi energy kBTF; as a consequence the polarization tends to unity and s-wave quasiparticle scattering is suppressed for T<

8.
Phys Rev Lett ; 99(4): 046601, 2007 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-17678384

RESUMEN

We report the observation of strong electron dephasing in a series of disordered Cu93Ge4Au3 thin films. A very short electron dephasing time possessing very weak temperature dependence around 6 K, followed by an upturn with further decrease in temperature below 4 K, is found. The upturn is progressively more pronounced in more disordered samples. Moreover, a lnT-dependent, but high-magnetic-field-insensitive, resistance rise persisting from above 10 K down to 30 mK is observed in the films. These results suggest a nonmagnetic dephasing process which is stronger than any known mechanism and may originate from the coupling of conduction electrons to dynamic defects.

9.
Phys Rev Lett ; 99(25): 256403, 2007 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-18233536

RESUMEN

We have investigated the Mott transition in a quasi-two-dimensional Mott insulator EtMe{3}P[Pd(dmit){2}]{2} with a spin-frustrated triangular-lattice in hydrostatic pressure and magnetic-field [Et and Me denote C2H5 and CH3, respectively, and Pd(dmit){2} (dmit=1,3-dithiole-2-thione-4,5-dithiolate,dithiolate) is an electron-acceptor molecule]. In the pressure-temperature (P-T) phase diagram, a valence-bond solid phase is found to neighbor the superconductor and metal phases at low temperatures. The profile of the phase diagram is common to those of Mott insulators with antiferromagnetic order. In contrast to the antiferromagnetic Mott insulators, the resistivity in the metallic phase exhibits anomalous temperature dependence, rho=rho{0}+AT(2.5).

10.
Acta Neurochir Suppl ; 96: 168-70, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16671448

RESUMEN

We investigated the correlation between the changes in diffusion tensor magnetic resonance imaging, regional water content, and tissue ultrastructure after vasogenic brain edema induced by cortical cold lesioning. In this cat model, E3 in the white matter was dominantly increased while fractional anisotropy (FA) was significantly decreased 8 hours after cortical cold lesioning. This finding indicates that water diffusion in the cortical white matter mainly increased perpendicularly rather than parallel to the direction of the nerve fibers. Additionally, in the area where edema is mild or moderate (tissues with water content of 65% to 75%), FA in the chronic phase was significantly lower than that in the acute phase. Histological examination demonstrated disordered arrangement of nerve fibers, highly dissociated neuronal fibers due to extracellular accumulation of protein rich-fluid, and enlarged interfiber spaces in the acute phase.


Asunto(s)
Agua Corporal/metabolismo , Edema Encefálico/diagnóstico , Edema Encefálico/metabolismo , Encéfalo/metabolismo , Encéfalo/patología , Imagen de Difusión por Resonancia Magnética/métodos , Modelos Animales de Enfermedad , Animales , Edema Encefálico/patología , Gatos
11.
Interv Neuroradiol ; 12(Suppl 1): 97-100, 2006 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-20569610

RESUMEN

SUMMARY: Small ruptured cerebral aneurysms, such as those of 2x3 mm diameter, are considered to be difficult to embolize by detachable coils because of the risk of procedural perforation of the aneurysms. We have treated these small aneurysms and report the techniques and pitfalls of these embolizations. Twenty-four patients with ruptured cerebral aneurysms of 2x3 mm diameter were intended for treatment by coil embolization. Before coil embolization, three-dimensional digital subtraction angiography was performed, and the simulation of the volume embolization ratio (VER) was performed in all patients, except for the first basilar artery aneurysm patient. The tip of the microcatheter was steam-shaped several times and was placed on the neck of the aneurysm. A balloon neck remodeling technique was used for two aneurysms. GDC 10 softs and soft SRs were used for the first ten aneurysms, and Ultrasofts were used for the last eleven aneurysms. Out of twentyfour aneurysm embolizations, we aborted the procedure in three cases, because of a failure in catheterization; we performed clipping surgery for these cases. For the first case of a basilar tip aneurysm, the aneurysm was perforated, due to the use of too long a coil and the insertion of the tip of the microcatheter into the aneurysmal dome. Minor infarction occurred in one patient. The mean VER was 33.9%, and two aneurysms recanalized, and out of these one needed a second embolization. Six months postoperatively, 81% of patients had made in a good recovery or had a moderate disability.We recommend the following techniques to embolize aneurysms of 2x3 mm diameter: the tip of the microcatheter should be stabilized on the aneurysmal neck by steam shaping of the microcatheter, GDC 10 soft and Ultrasoft should be selected for use, and the simulation of the VER should be performed before embolization to select coils of a suitable length.

12.
Phys Rev Lett ; 94(9): 091801, 2005 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-15783953

RESUMEN

Exploiting the manipulation of the SLAC Linear Collider electron-beam polarization, we present precise direct measurements of the parity-violation parameters A(c) and A(b) in the Z-boson-c-quark and Z-boson-b-quark coupling. Quark-antiquark discrimination is accomplished via a unique algorithm that takes advantage of the precise SLAC Large Detector charge coupled device vertex detector, employing the net charge of displaced vertices as well as the charge of kaons that emanate from those vertices. From the 1996-1998 sample of 400 000 Z decays, produced with an average beam polarization of 73.4%, we find A(c)=0.673+/-0.029(stat)+/-0.023(syst) and A(b)=0.919+/-0.018(stat)+/-0.017(syst).

13.
Phys Rev Lett ; 93(14): 141601, 2004 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-15524780

RESUMEN

We report results from a study of events with a double-Pomeron exchange topology produced in p p collisions at sqrt[s]=1800 GeV. The events are characterized by a leading antiproton and a large rapidity gap on the outgoing proton side. We find that the differential production cross section agrees in shape with predictions based on Regge theory and factorization, and that the ratio of double-Pomeron exchange to single diffractive production rates is relatively unsuppressed as compared to the O(10) suppression factor previously measured in single diffractive production.

14.
Phys Rev Lett ; 92(12): 121802, 2004 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-15089665

RESUMEN

We report on a search for direct Kaluza-Klein graviton production in a data sample of 84 pb(-1) of ppmacr; collisions at sqrt[s]=1.8 TeV, recorded by the Collider Detector at Fermilab. We investigate the final state of large missing transverse energy and one or two high energy jets. We compare the data with the predictions from a (3+1+n)-dimensional Kaluza-Klein scenario in which gravity becomes strong at the TeV scale. At 95% confidence level (C.L.) for n=2, 4, and 6 we exclude an effective Planck scale below 1.0, 0.77, and 0.71 TeV, respectively.

15.
Phys Rev Lett ; 92(5): 051803, 2004 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-14995297

RESUMEN

We present the results of a search for pair production of scalar top quarks (t(1)) in an R-parity violating supersymmetry scenario in 106 pb(-1) of pp collisions at square root of s=1.8 TeV collected by the Collider Detector at Fermilab. In this mode each t(1) decays into a tau lepton and a b quark. We search for events with two tau's, one decaying leptonically (e or mu) and one decaying hadronically, and two jets. No candidate events pass our final selection criteria. We set a 95% confidence level lower limit on the t(1) mass at 122 GeV/c(2) for Br(t(1)-->tau b)=1.

16.
Phys Rev Lett ; 91(17): 171602, 2003 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-14611332

RESUMEN

We report on a search for a high mass, narrow width particle that decays directly to emu, etau, or microtau. We use approximately 110 pb(-1) of data collected with the Collider Detector at Fermilab from 1992 to 1995. No evidence of lepton flavor violating decays is found. Limits are set on the production and decay of sneutrinos with R-parity violating interactions.

17.
Phys Rev Lett ; 91(1): 011802, 2003 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-12906532

RESUMEN

We report a measurement of the fraction of events with a large pseudorapidity gap deltaeta within the pseudorapidity region available to the proton dissociation products X in p+p-->p+X. For a final state p of fractional momentum loss xi(p) and 4-momentum transfer squared t(p) within 0.063 is found to be 0.246+/-0.001 (stat)+/-0.042 (syst) [0.184+/-0.001 (stat)+/-0.043 (syst)]. Our results are compared with gap fractions measured in minimum bias pp collisions and with theoretical expectations.

18.
Phys Rev Lett ; 90(25 Pt 1): 251801, 2003 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-12857123

RESUMEN

We have searched for pair production of the supersymmetric partner of the top quark (stop) in 107 pb(-1) of pp collisions at square root of s=1.8 TeV collected by the Collider Detector at Fermilab (CDF). Each stop is assumed to decay into a lepton, bottom quark, and supersymmetric neutrino. Such a scenario would give rise to events with two leptons, two hadronic jets, and a substantial imbalance of transverse energy. No evidence of such a stop signal has been found. We exclude stop masses in the region (80

19.
Phys Rev Lett ; 90(22): 221803, 2003 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-12857307

RESUMEN

We present a search for associated production of the Upsilon(1S) and a vector boson in 83 pb(-1) of ppmacr; collisions at sqrt[s]=1.8 TeV collected by the CDF experiment in 1994-1995. We find no evidence of the searched signal in the data, and set upper limits to the production cross sections.

20.
Phys Rev Lett ; 90(14): 141804, 2003 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-12731908

RESUMEN

We present an improved direct measurement of the parity-violation parameter A(b) in the Z boson-b-quark coupling using a self-calibrating track-charge technique applied to a sample enriched in Z-->bb events via the topological reconstruction of the B hadron mass. Manipulation of the Stanford Linear Collider electron-beam polarization permits the measurement of A(b) to be made independently of other Z-pole coupling parameters. From the 1996-1998 sample of 400,000 hadronic Z decays, produced with an average beam polarization of 73.4%, we find A(b)=0.906+/-0.022(stat)+/-0.023(syst).

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