4,033 research outputs found
70. Ocena skuteczności przeciwbólowej radioterapii ostróg piętowych
Założenia i cel pracyOdokostnowy wzrost kości w miejscu przyczepu ścięgien do kości piętowej (ostrogi) często jest powodem uciążliwych bólów. Celem naszej pracy była ocena skuteczności radioterapii, jako metody leczenia tych zespołów bólowych.Materiał i metodykaRetrospektywny materiał obejmował 798 przypadków (181 M, 617 K) bolesnych ostróg kości piętowych napromienianych przy użyciu dawki frakcyjnej 1–3 Gy (średnia 1,5 Gy) do dawki całkowitej zawierającej się w przedziale od 1,5 do 22,5 Gy (średnia 8 Gy). Wiek chorych zawierał się w przedziale od 24 do 85 lat (średnia 56). Podobna liczba zmian była zlokalizowana po lewej i prawej stronie. Średnia wielkość ostrogi wynosiła 0,9 cm, a średnia wielkość napromienianego pola 57 cm2. Średni czas trwania objawów wynosił 32 miesiące. W 155 przypadkach było to powtórne napromienianie. W 768 przypadkach zastosowano promieniowanie X, w 18 wysokoenergetyczne fotony, w 9 elektrony, a w 3 promieniowanie gamma. Średni okres obserwacji wynosił 17,5 miesiąca. Oceniono stopień zmniejszenia bólu po zakończeniu leczenia oraz czas utrzymywania się efektu przeciwbólowego. Obliczono odsetek chorych nie zgłaszających bólu spoczynkowego oraz bólu w trakcie chodzenia podczas ostatniej kontroli.WynikiPo zakończeniu radioterapii całkowite ustąpienie bólu odnotowano w 44%. W pozostałej grupie zmniejszenie bólu o więcej niż 50% w stosunku do stanu z przed leczenia osiągnięto u 42%, o mniej niż 50% u 28%, a w 30% nie odnotowano efektu przeciwbólowego. Średni czas utrzymywania się efektu wyniósł 12 miesięcy. Podczas ostatniej kontroli 45% chorych nie zgłaszało bólów w spoczynku, a 29% podczas chodzenia.WniosekOtrzymane wyniki pozwa1ają na sformułowanie wniosku, że radioterapia jest skuteczną i bezpieczną metodą leczenia bolesnych ostróg kości piętowych oraz może być stosowane w przypadkach nie poddających się leczeniu konwencjonalnemu
Faddeev study of heavy baryon spectroscopy
We investigate the structure of heavy baryons containing a charm or a bottom
quark. We employ a constituent quark model successful in the description of the
baryon-baryon interaction which is consistent with the light baryon spectra. We
solve exactly the three-quark problem by means of the Faddeev method in
momentum space. Heavy baryon spectrum shows a manifest compromise between
perturbative and nonperturbative contributions. The flavor dependence of the
one-gluon exchange is analyzed. We assign quantum numbers to some already
observed resonances and we predict the first radial and orbital excitations of
all states with or 3/2. We combine our results with heavy quark
symmetry and lowest-order SU(3) symmetry breaking to predict the masses and
quantum numbers of six still non-measured ground-state beauty baryons.Comment: 22 pages, 4 figures, 8 tables. Accepted for publication in J. Phys.
New Particles from Belle
I report recent results on hidden charm spectroscopy from Belle. These
include: observation of a near-threshold enhancement in the omega-J/psi
invariant mass distribution for exclusive B-->K omega J/psi decays; evidence
for the decay X(3872)-->pi+pi-pi0 J/psi, where the pi+pi-pi0 invariant mass
distribution has a strong peak between 750 MeV and the kinematic limit of 775
MeV, suggesting that the process is dominated by the sub-threshold decay
X-->omega J/psi; and the observation of a peak near 3940 MeV in the J/psi
recoil mass spectrum for the inclusive continuum process e+e- --> J/psi X. The
results are based on a study of a 287 fb-1 sample of e+e- annihilation data
collected at center- of-mass energies around the Upsilon(4S) in the Belle
detector at the KEKB collider.Comment: 10 pages 12 figures. Invited talk at the 1st meeting of the APS
Topical Group on Hadronic Physics, Fermilab, October 24-26, 2004; revised to
correct some reference
Heavy Quark Spectroscopy -- Theory Overview
Some recent discoveries in the spectroscopy of hadrons containing heavy
quarks, and some of their theoretical interpretations, are reviewed.Comment: 13 pages, 6 figures. Presented at Second Meeting of APS Topical Group
on Hadron Physics, Nashville, TN, 22-24. Proceedings to be published by
Journal of Physics (UK), Conference Series. Uses jpconf.cls, jpconf11.clo.
Some corrections; references update
Measurement Of |V_ub| From Inclusive Charmless Semileptonic B Decays
We present the partial branching fraction for inclusive charmless
semileptonic B decays and the corresponding value of the CKM matrix element
|Vub|, using a multivariate analysis method to access ~90% of the B -> Xu l nu
phase space. This approach dramatically reduces the theoretical uncertainties
from the b-quark mass and non-perturbative QCD compared to all previous
inclusive measurements. The results are based on a sample of 657 million B
-Bbar pairs collected with the Belle detector. We find that Delta BR(B -> Xu l
nu; p^*B_l>1.0 GeV/c=1.963 x (1 +/- 0.088(stat.) +/- 0.081(sys.)) x 10^-3.
Corresponding values of |Vub| are extracted using several theoretical
calculations.Comment: 9 pages, 1 figure, 2 tables. Published in PR
Measurement of shower development and its Moli\`ere radius with a four-plane LumiCal test set-up
A prototype of a luminometer, designed for a future e+e- collider detector,
and consisting at present of a four-plane module, was tested in the CERN PS
accelerator T9 beam. The objective of this beam test was to demonstrate a
multi-plane tungsten/silicon operation, to study the development of the
electromagnetic shower and to compare it with MC simulations. The Moli\`ere
radius has been determined to be 24.0 +/- 0.6 (stat.) +/- 1.5 (syst.) mm using
a parametrization of the shower shape. Very good agreement was found between
data and a detailed Geant4 simulation.Comment: Paper published in Eur. Phys. J., includes 25 figures and 3 Table
Structure–activity relationships of dinucleotides: Potent and selective agonists of P2Y receptors
Dinucleoside polyphosphates act as agonists on purinergic P2Y receptors to mediate a variety of cellular processes. Symmetrical, naturally occurring purine dinucleotides are found in most living cells and their actions are generally known. Unsymmetrical purine dinucleotides and all pyrimidine containing dinucleotides, however, are not as common and therefore their actions are not well understood. To carry out a thorough examination of the activities and specificities of these dinucleotides, a robust method of synthesis was developed to allow manipulation of either nucleoside of the dinucleotide as well as the phosphate chain lengths. Adenosine containing dinucleotides exhibit some level of activity on P2Y1 while uridine containing dinucleotides have some level of agonist response on P2Y2 and P2Y6. The length of the linking phosphate chain determines a different specificity; diphosphates are most accurately mimicked by dinucleoside triphosphates and triphosphates most resemble dinucleoside tetraphosphates. The pharmacological activities and relative metabolic stabilities of these dinucleotides are reported with their potential therapeutic applications being discussed
Measurements of Charmless Hadronic b->s Penguin Decays in the pi+pi-K+pi- Final State and First Observation of B0 -> rho0K+pi-
We report measurements of charmless hadronic B^0 decays into the pi+pi-K+pi+
final state. The analysis uses a sample of 657x10^6 BBbar pairs collected with
the Belle detector at the KEKB asymmetric-energy e+e- collider at the Y(4S)
resonance. The decay B^0 -> rho0 Kpi is observed for the first time; the
significance is 5.0sigma and the corresponding partial branching fraction for
M_Kpi in (0.75,1.20) GeV/c^2 is [2.8 +- 0.5(stat) +-0.5(syst)] x 10^{-6}. We
also obtain the first evidence for B^0 -> f0Kpi with 3.5sigma significance and
for B^0 -> pi+pi-K*0 with 4.5sigma significance. For the two-body decays B^0 ->
rho0K*0 and B^0 -> f0K*0, the significances are 2.7sigma and 2.5sigma,
respectively, and the upper limits on the branching fractions are 3.4x10^{-6}
and 2.2x10^{-6} at 90% confidence level.Comment: 6 pages, 3 figures. accepted by PRD(RC
Performance of fully instrumented detector planes of the forward calorimeter of a Linear Collider detector
Detector-plane prototypes of the very forward calorimetry of a future
detector at an e+e- collider have been built and their performance was measured
in an electron beam. The detector plane comprises silicon or GaAs pad sensors,
dedicated front-end and ADC ASICs, and an FPGA for data concentration.
Measurements of the signal-to-noise ratio and the response as a function of the
position of the sensor are presented. A deconvolution method is successfully
applied, and a comparison of the measured shower shape as a function of the
absorber depth with a Monte-Carlo simulation is given.Comment: 25 pages, 32 figures, revised version following comments from
referee
Dalitz analysis of B --> K pi psi' decays and the Z(4430)+
From a Dalitz plot analysis of B --> K pi psi' decays, we find a signal for
Z(4430)+ --> pi+ psi' with a mass M= (4443(+15-12)(+19-13))MeV/c^2, width
Gamma= (107(+86-43)(+74-56))MeV, product branching fraction BR(B0 --> K-
Z(4430)+) x BR(Z(4430)+ --> pi+ psi')= (3.2(+1.8-0.9)(+5.3-1.6)) x 10^{-5}, and
significance of 6.4sigma that agrees with previous Belle measurements based on
the same data sample. In addition, we determine the branching fraction BR(B^0
--> K*(892)^0 psi')= (5.52(+0.35-0.32)(+0.53-0.58)) x 10^{-4} and the fraction
of K*(892)^0 mesons that are longitudinally polarized f_L=
44.8(+4.0-2.7)(+4.0-5.3)%. These results are obtained from a 605fb^{-1} data
sample that contains 657 million B-anti-B pairs collected near the Upsilon(4S)
resonance with the Belle detector at the KEKB asymmetric energy e+e- collider.Comment: Final version published in PRD(RC
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