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1.
Phys Rev E ; 107(5-2): 055202, 2023 May.
Article in English | MEDLINE | ID: mdl-37329017

ABSTRACT

Employing the quantum magnetohydrodynamic (QMHD) model, the basic properties of magnetosonic waves were investigated in a magnetorotating quantum plasma. The contemplated system considered a combined effects of quantum tunneling and degeneracy forces, dissipation influence, spin magnetization, in addition to the Coriolis force. Fast and slow magnetosonic modes were obtained and examined in the linear regime. Their frequencies are significantly modified due to the rotating parameters (frequency and angle) in addition to quantum correction effects. The nonlinear Korteweg-de Vries-Burger equation was derived using the reductive perturbation approach in a small amplitude limit. The aspects of magnetosonic shock profiles were explored analytically by applying the Bernoulli equation approach and numerically using the Runge-Kutta method. The regarded plasma parameters due to the investigated effects were found to play major roles in specifying the nature of monotonic and oscillatory shock waves' structures and their features. Our results may be applicable in magnetorotating quantum plasma in astrophysical environments such as neutron stars and white dwarfs.


Subject(s)
Plasma , Reproduction
2.
Brain Res ; 1208: 111-9, 2008 May 07.
Article in English | MEDLINE | ID: mdl-18395190

ABSTRACT

Peripheral nerve injury in animals can cause neuropathic pain often expressed in the form of hyperalgesia and allodynia. Spinal nerve ligation, in which the fifth and sixth lumbar (L5 and L6) or only the L5 spinal nerve is ligated and cut, is a model commonly used to produce neuropathic pain. The purpose of the present study was to test whether there is any anatomical evidence to support the suggestion that terminating unmyelinated (C) fibres of injured and adjacent uninjured nerves interact at the level of the spinal dorsal horn. Thus, in the first series of experiments, rats received injections of anterograde tracers, either wheat germ agglutinin (WGA) conjugated to horseradish peroxidase or Bandeiraea simplicifolia isolectin B4 (IB4), into the L4 or L5 spinal nerves. Results with both tracers showed that the central terminals of nerve L4 were concentrated in both L4 and L3 segments of the dorsal horn with clear although reduced levels of labelling in L2 and L5. Similarly, the central terminals of nerve L5 were found in both L5 and L4 again with less labelling in L3 and L6. These results suggest an intermingling of primary afferents of adjacent nerves at the level of the spinal dorsal horn. A second series of experiments was therefore conducted to test whether primary afferent terminals from adjacent nerves target the same neuronal elements in the regions of overlap. Consequently, additional rats were injected with WGA into the L5 spinal nerve and IB4 into the adjacent L4 spinal nerve. Double immunofluorescent staining and confocal microscopy revealed that IB4-labelled and WGA-labelled boutons, belonging to L4 and L5 spinal nerves, terminated in the same region within the L4 spinal segment. This suggests that neurons located in regions of overlap receive input from both L4 (intact) and L5 (injured) afferents. Consequently, spinal neurons located in regions of terminal overlap may show augmented responses to activation of the intact L4 nerve due to neuronal sensitisation resulting from injury to the adjacent L5 nerve. This may in part provide an anatomical basis for hyperalgesic reaction to injury.


Subject(s)
Nerve Fibers, Unmyelinated/physiology , Spinal Cord/physiology , Spinal Nerve Roots/physiology , Afferent Pathways/physiology , Animals , Cholera Toxin/metabolism , Female , Ganglia, Spinal/physiology , Ligation/methods , Male , Microscopy, Confocal , Rats , Rats, Wistar , Spinal Cord/anatomy & histology , Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate/metabolism
3.
Phys Rev Lett ; 94(1): 011802, 2005 Jan 14.
Article in English | MEDLINE | ID: mdl-15698066

ABSTRACT

We investigate the decays D(0)-->pi(-)l(+)nu and D(0)-->K(-)l(+)nu, where l is e or mu, using approximately 7 fb(-1) of data collected with the CLEO III detector. We find R(0) identical with B(D(0)-->pi(-)e(+)nu)/B(D(0)-->K(-)e(+)nu)=0.082+/-0.006+/-0.005. Fits to the kinematic distributions of the data provide parameters describing the form factor of each mode. Combining the form factor results and R(0) gives |f(pi)(+)(0)|(2)|V(cd)|(2)/|f(K)(+)(0)|(2)|V(cs)|(2)=0.038(+0.006+0.005)(-0.007-0.003).

4.
Phys Rev Lett ; 94(3): 032004, 2005 Jan 28.
Article in English | MEDLINE | ID: mdl-15698254

ABSTRACT

We report on a search for the recently reported X(3872) state using 15.1 fb(-1) of e(+)e(-) data taken in the sqrt[s] = 9.46-11.30 GeV region. Separate searches for the production of the X(3872) in untagged gammagamma fusion and e(+)e(-) annihilation following initial state radiation are made by taking advantage of the unique angular correlation between the leptons from the decay J/psi --> l(+)l(-) in X(3872) decay to pi(+)pi(-)J/psi. No signals are observed in either case, and 90% confidence upper limits are established as (2J+1)Gamma(gammagamma)(X(3872))B(X --> pi(+)pi(-)J/psi) < 12.9 eV and Gamma(ee)(X(3872))B(X- -> pi(+)pi(-)J/psi) < 8.3 eV.

5.
Phys Rev Lett ; 92(23): 232001, 2004 Jun 11.
Article in English | MEDLINE | ID: mdl-15245150

ABSTRACT

We present the first study of the vector (Wess-Zumino) current in tau(-)-->K-pi-K+nu(tau) decay using data collected with the CLEO III detector at the Cornell Electron Storage Ring. We determine the quantitative contributions to the decay width from the vector and axial vector currents. Within the framework of a model by Kühn and Mirkes, we identify the quantitative contributions to the total decay rate from the intermediate states omegapi, rho(')pi, and K*K.

6.
Phys Rev Lett ; 92(22): 222002, 2004 Jun 04.
Article in English | MEDLINE | ID: mdl-15245215

ABSTRACT

The CLEO Collaboration has made the first observations of hadronic transitions among bottomonium (bbmacr;) states other than the dipion transitions among Upsilon(nS) states. In our study of Upsilon(3S) decays, we find a significant signal for Upsilon(3S)-->gammaomegaUpsilon(1S) that is consistent with radiative decays Upsilon(3S)-->gammachi(b1,2)(2P), followed by chi(b1,2)(2P)-->omegaUpsilon(1S). The branching ratios we obtain are B[chi(b1)(2P)-->omegaUpsilon(1S)]=(1.63(+0.35+0.16)(-0.31-0.15))% and B[chi(b2)(2P)-->omegaUpsilon(1S)]=(1.10(+0.32+0.11)(-0.28-0.10))%, in which the first error is statistical and the second is systematic.

7.
Phys Rev Lett ; 92(14): 142001, 2004 Apr 09.
Article in English | MEDLINE | ID: mdl-15089529

ABSTRACT

We report on the observation of the eta(')(c)(2(1)S0), the radial excitation of the eta(c)(1(1)S0) ground state of charmonium, in the two-photon fusion reaction gammagamma-->eta(')(c)-->K(0)(S)K+/-pi(-/+) in 13.6 fb(-1) of CLEO II/II.V data and 13.1 fb(-1) of CLEO III data. We obtain M(eta(')(c))=3642.9+/-3.1(stat)+/-1.5(syst) MeV and M(eta(c))=2981.8+/-1.3(stat)+/-1.5(syst) MeV. The corresponding values of hyperfine splittings between 1S0 and 3S1 states are DeltaM(hf)(1S)=115.1+/-2.0 MeV and DeltaM(hf)(2S)=43.1+/-3.4 MeV. Assuming that the eta(c) and eta(')(c) have equal branching fractions to K(S)Kpi, we obtain Gamma(gammagamma)(eta(')(c))=1.3+/-0.6 keV.

8.
Phys Rev Lett ; 90(10): 101801, 2003 Mar 14.
Article in English | MEDLINE | ID: mdl-12688989

ABSTRACT

Using 13.8 fb(-1) of data collected at or just below the Upsilon(4S) with the CLEO detector, we report the result of a search for the flavor changing neutral current process D0-->gammagamma. We observe no significant signal for this decay mode and determine 90% confidence level upper limits on the branching fractions B(D0-->gammagamma)/B(D0-->pi(0)pi(0))<0.033 and B(D0-->gammagamma)<2.9 x 10(-5).

9.
Phys Rev Lett ; 89(25): 251801, 2002 Dec 16.
Article in English | MEDLINE | ID: mdl-12484873

ABSTRACT

We report on a search for charmless hadronic B decays to the three-body final states K(0)(S)h(+)pi(-), K(+)h(-)pi(0), K(0)(S)h(+)pi(0) (h(+/-) denotes a charged pion or kaon), and their charge conjugates, using 13.5 fb(-1) of integrated luminosity produced near sqrt[s]=10.6 GeV, and collected with the CLEO detector. We observe the decay B-->K0pi(+)pi(-) with a branching fraction (50(+10)(-9)(stat.)+/-7(syst.))x10(-6) and the decay B-->K(*+)(892)pi(-) with a branching fraction (16(+6)(-5)(stat.)+/-2(syst.))x10(-6).

10.
Phys Rev Lett ; 89(25): 251802, 2002 Dec 16.
Article in English | MEDLINE | ID: mdl-12484874

ABSTRACT

In e(+)e(-) collisions using the CLEO detector, we have studied the decay of the D0 to the final state K(0)(S)pi(+)pi(-) with the initial flavor of the D0 tagged by the decay D(*+)-->D0pi(+). We use the Dalitz technique to measure the resonant substructure in this final state and clearly observe ten different contributions by fitting for their amplitudes and relative phases. We observe a K(*)(892)(+)pi(-) component which arises from doubly Cabibbo suppressed decays or D0-D0; mixing.

11.
Phys Rev Lett ; 88(6): 062001, 2002 Feb 11.
Article in English | MEDLINE | ID: mdl-11863797

ABSTRACT

We have studied the color-suppressed hadronic decays of neutral B mesons into the final states D*0pi(0). Using 9.67 x 10(6) BB pairs collected with the CLEO detector, we observe the decays B( 0) --> D0pi(0) and B( 0) -->D(*0)pi(0) with the branching fractions BB( 0) -->D0pi(0)) = (2.74(+0.36)(-0.32) +/- 0.55)x10(-4) and BB( 0) -->D(*0)pi(0)) = (2.20(+0.59)(-0.52) +/- 0.79)x10(-4). The first error is statistical and the second systematic. The statistical significance of the D0pi(0) signal is 12.1sigma ( 5.9sigma for D(*0)pi(0)). Utilizing the B( 0) -->D*0)pi(0) branching fractions we determine the strong phases delta(I,D(*)) between isospin 1/2 and 3/2 amplitudes in the Dpi and D*pi final states to be cosdelta(I,D) = 0.89 +/-0.08 and cosdelta(I,D*) = 0.89 +/- 0.08, respectively.

13.
Phys Rev Lett ; 87(25): 251807, 2001 Dec 17.
Article in English | MEDLINE | ID: mdl-11736566

ABSTRACT

We have measured the branching fraction and photon energy spectrum for the radiative penguin process b-->s gamma. We find Beta(b-->s gamma) = (3.21+/-0.43+/-0.27(+0.18)(-0.10))x10(-4), where the errors are statistical, systematic, and from theory corrections. We obtain first and second moments of the photon energy spectrum above 2.0 GeV, = 2.346+/-0.032+/-0.011 GeV, and -(2) = 0.0226+/-0.0066+/-0.0020 GeV(2), where the errors are statistical and systematic. From the first moment, we obtain (in the modified minimal subtraction renormalization scheme, to order 1/M(3)(B) and beta(0)alpha(2)(s)) the heavy quark effective theory parameter Lambda = 0.35+/-0.08+/-0.10 GeV.

14.
Phys Rev Lett ; 87(25): 251808, 2001 Dec 17.
Article in English | MEDLINE | ID: mdl-11736567

ABSTRACT

We have measured the first and second moments of the hadronic mass-squared distribution in B-->X(c)l nu, for P(lepton)>1.5 GeV/c. We find = 0.251+/-0.066 GeV(2), <(M(2)(X)-)(2)> = 0.576+/-0.170 GeV(4), where M macro(D) is the spin-averaged D meson mass. From that first moment and the first moment of the photon energy spectrum in b-->s gamma, we find the heavy quark effective theory parameter lambda(1) (in the modified minimal subtraction renormalization scheme, to order 1/M(3)(B) and beta(0)alpha(2)(s)) to be -0.24+/-0.11 GeV(2). Using these first moments and the B semileptonic width, and assuming parton-hadron duality, we obtain absolute value of V(cb) = 0.0404+/-0.0013.

15.
Phys Rev Lett ; 87(14): 141801, 2001 Oct 01.
Article in English | MEDLINE | ID: mdl-11580641

ABSTRACT

We report on a search for the radiative decay Upsilon(1S)-->gammaeta(') in 61.3 pb(-1) of data taken with the CLEO II detector at the Cornell Electron Storage Ring. Three decay chains were investigated, all involving eta(')-->pi(+)pi(-)eta, followed by eta-->gammagamma, eta-->pi(0)pi(0)pi(0), or eta-->pi(+)pi(-)pi(0). We find no candidate events in any of the three cases and set a combined upper limit of 1.6x10(-5) at 90% C.L., significantly smaller than the previous limit. We compare our result to other radiative Upsilon decays, to radiative J/psi decays, and to theoretical predictions.

16.
Bull World Health Organ ; 79(7): 648-56, 2001.
Article in English | MEDLINE | ID: mdl-11477968

ABSTRACT

In countries where malaria is endemic, routine blood slide examinations remain the major source of data for the public health surveillance system. This approach has become inadequate, however, as the public health emphasis has changed from surveillance of laboratory-confirmed malaria infections to the early detection and treatment of the disease. As a result, it has been advocated that the information collected about malaria be changed radically and should include the monitoring of morbidity and mortality, clinical practice and quality of care. To improve the early diagnosis and prompt treatment (EDPT) of malaria patients, three malaria case definitions (MCDs) were developed, with treatment and reporting guidelines, and used in all static health facilities of Cox's Bazar district, Bangladesh (population 1.5 million). The three MCDs were: uncomplicated malaria (UM); treatment failure malaria (TFM); and severe malaria (SM). The number of malaria deaths was also reported. This paper reviews the rationale and need for MCDs in malaria control programmes and presents an analysis of the integrated surveillance information collected during the three-year period, 1995-97. The combined analysis of slide-based and clinical data and their related indicators shows that blood slide analysis is no longer used to document fever episodes but to support EDPT, with priority given to SM and TFM patients. Data indicate a decrease in the overall positive predictive value of the three MCDs as malaria prevalence decreases. Hence the data quantify the extent to which the mainly clinical diagnosis of UM leads to over-diagnosis and over-treatment in changing epidemiological conditions. Also the new surveillance data show: a halving in the case fatality rate among SM cases (from 6% to 3.1%) attributable to improved quality of care, and a stable proportion of TFM cases (around 7%) against a defined population denominator. Changes implemented in the EDPT of malaria patients and in the surveillance system were based on existing staff capacity and routine reporting structures.


Subject(s)
Malaria, Falciparum/diagnosis , Population Surveillance , Bangladesh/epidemiology , Communicable Disease Control , Endemic Diseases , Guidelines as Topic , Humans , Malaria, Falciparum/classification , Malaria, Falciparum/epidemiology , Malaria, Falciparum/therapy , Outcome Assessment, Health Care , Urban Population
17.
Phys Rev Lett ; 86(20): 4479-82, 2001 May 14.
Article in English | MEDLINE | ID: mdl-11384263

ABSTRACT

Using 13.7 fb(-1) of data recorded by the CLEO detector at the Cornell Electron Storage Ring, we investigate the spectrum of charmed baryons which decay into Lambda+(c)pi(-)pi(+) and are more massive than the Lambda+(c)(2625) baryon. We find evidence for two new states: one is broad and has an invariant mass roughly 480 MeV above that of the Lambda+(c) baryon; the other is narrow with an invariant mass of 596+/-1+/-2 MeV above the Lambda+(c) mass.

18.
Phys Rev Lett ; 86(25): 5661-5, 2001 Jun 18.
Article in English | MEDLINE | ID: mdl-11415327

ABSTRACT

We have measured the CP asymmetry A(CP) identical with[gamma(b-->sgamma)-gammab-->sgamma)]/[gamma(b-->sgamma)+gamma(b-->sgamma)] to be A(CP) = (-0.079+/-0.108+/-0.022) (1.0+/-0.030), implying that, at 90% confidence level, A(CP) lies between -0.27 and +0.10. These limits rule out some extreme non-standard-model predictions, but are consistent with most, as well as with the standard model.

19.
Phys Rev Lett ; 86(17): 3730-4, 2001 Apr 23.
Article in English | MEDLINE | ID: mdl-11329310

ABSTRACT

The CLEO experiment at the CESR collider has used 13.7 fb(-1) of data to search for the production of the Omega(0)(c) (css ground state) in e(+)e(-) collisions at square root of (s) approximately 10.6 GeV. The modes used to study the Omega(0)(c) are Omega(-)pi(+), Omega(-)pi(+)pi(0), Xi-K-pi(+)pi(+), Xi0K-pi(+), and Omega(-)pi(+)pi(+)pi(-). We observe a signal of 40.4+/-9.0(stat) events at a mass of 2694.6+/-2.6(stat)+/-1.9(syst) MeV/c(2), for all modes combined.

20.
Phys Rev Lett ; 86(11): 2232-6, 2001 Mar 12.
Article in English | MEDLINE | ID: mdl-11289897

ABSTRACT

The Lambda+c lifetime is measured using 9.0 fb(-1) of e+e- annihilation data collected on or just below the Upsilon(4S) resonance with the CLEO II.V detector at CESR. Using an unbinned maximum likelihood fit, the Lambda+c lifetime is measured to be 179.6+/-6.9(stat)+/-4.4(syst) fs. The precision of this colliding beam measurement is comparable to other measurements, which are based on fixed-target experiments, with different systematic uncertainties.

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