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M Saleem

Publications and source records attributed to M Saleem.

At least 37 records · Page 2Linked to original sources
PubMed2005

Search for lepton-flavor and lepton-number violation in the decay tau(-) -->l-(+)h+(-)h'(-).

A search for lepton-flavor and lepton-number violation in the decay of the tau lepton into one charged lepton and two charged hadrons is performed using 221.4 fb(-1) of data collected at an e+e- center-of-mass energy of 10.58 GeV with the BABAR detector at the SLAC PEP-II storage ring. In all 14 decay modes considered, the observed data are compatible with background expectations, and upper limits are set in the range B(tau-->lhh')<(0.7 - 4.8) x 10(-7) at 90% confidence level.

Journal Article↗
PubMed2005

Measurement of time-dependent CP asymmetries and the CP-odd fraction in the decay B0-->D*+D*-.

We present an updated measurement of time-dependent CP asymmetries and the CP-odd fraction in the decay B0-->D*+D*- using 232x10(6)BB pairs collected by the BABAR detector at the SLAC PEP-II B factory. We determine the CP-odd fraction to be 0.125+/-0.044(stat)+/-0.007(syst). The time-dependent CP asymmetry parameters C+ and S+ are determined to be 0.06+/-0.17(stat)+/-0.03(syst) and -0.75+/-0.25(stat)+/-0.03(syst), respectively. The standard model predicts these parameters to be 0 and -sin2beta, respectively, in the absence of penguin amplitude contributions.

Journal Article↗
PubMed2005

Observation of a broad structure in the pi+ pi- J/psi mass spectrum around 4.26 GeV/c2.

We study initial-state radiation events, e+ e- --> gammaISR pi+ pi- J/psi, with data collected with the BABAR detector. We observe an accumulation of events near 4.26 GeV/c2 in the invariant-mass spectrum of pi+ pi- J/psi. Fits to the mass spectrum indicate that a broad resonance with a mass of about 4.26 GeV/c2 is required to describe the observed structure. The presence of additional narrow resonances cannot be excluded. The fitted width of the broad resonance is 50 to 90 MeV/c2, depending on the fit hypothesis.

Journal Article↗
PubMed2005

Determination of |Vub| from measurements of the electron and neutrino momenta in inclusive semileptonic B decays.

We present a determination of the Cabibbo-Kobayashi-Maskawa matrix element |Vub| based on the analysis of semileptonic B decays from a sample of 88 x 10(6) Gamma(4S) decays collected with the BABAR detector at the SLAC PEP-II e+e- storage ring. Charmless semileptonic B decays are selected using measurements of the electron energy and the invariant mass squared of the electron-neutrino pair. We obtain |Vub| =(3.95 +/- 0.26(+0.58)(-0.42) +/- 0.25) x 10(-3), where the errors represent experimental uncertainties, heavy quark parameter uncertainties, and theoretical uncertainties, respectively.

Journal Article↗
PubMed2005

Circulating endothelial cells are elevated in patients with type 2 diabetes mellitus independently of HbA(1)c.

AIMS/HYPOTHESIS: Patients with diabetes mellitus are well known to be at high risk for vascular disease. Circulating endothelial cells (CECs) have been reported to be an ex vivo indicator of vascular injury. We investigated the presence of CECs in the peripheral blood of 25 patients with diabetes mellitus and in nine non-diabetic control donors. METHODS: Endothelial cells were isolated from peripheral blood with anti-CD-146-coated immunomagnetic Dynabeads, and were stained with acridine orange dye and counted by fluorescence microscopy. The cells were also stained for von Willebrand factor and Ulex europaeus lectin 1. RESULTS: Patients with diabetes mellitus had an elevated number of CECs (mean 69+/-30 cells/ml, range 35-126) compared with healthy controls (mean 10+/-5 cells/ml, range 3-18) (p<0.001). The increase in CECs did not correlate with the levels of HbA(1)c. Circulating endothelial cell numbers were elevated regardless of glucose levels, suggesting that, even with control of glucose levels, there is increased endothelial cell sloughing. CONCLUSIONS: Our study suggests that the higher number of CECs in patients with type 2 diabetes may reflect ongoing vascular injury that is not directly dependent on glucose control.

Adult↗
PubMed2005

Prostate abscess presenting as priapism.

Abscesses of the prostate are infrequently encountered now as a result of effective antibiotics. The clinical diagnosis remains difficult. Herein we report an unusual case of a prostate abscess presenting as priapism. The diagnosis and management of the case is discussed, and the literature is reviewed.

Abscess↗
PubMed2004

Comparison of computer-assisted instruction (CAI) versus traditional textbook methods for training in abdominal examination (Japanese experience).

PURPOSE: This study aimed to compare the effects of computer-assisted, text-based and computer-and-text learning conditions on the performances of 3 groups of medical students in the pre-clinical years of their programme, taking into account their academic achievement to date. A fourth group of students served as a control (no-study) group. METHOD: Participants were recruited from the pre-clinical years of the training programmes in 2 medical schools in Japan, Jichi Medical School near Tokyo and Kochi Medical School near Osaka. Participants were randomly assigned to 4 learning conditions and tested before and after the study on their knowledge of and skill in performing an abdominal examination, in a multiple-choice test and an objective structured clinical examination (OSCE), respectively. Information about performance in the programme was collected from school records and students were classified as average, good or excellent. Student and faculty evaluations of their experience in the study were explored by means of a short evaluation survey. RESULTS: Compared to the control group, all 3 study groups exhibited significant gains in performance on knowledge and performance measures. For the knowledge measure, the gains of the computer-assisted and computer-assisted plus text-based learning groups were significantly greater than the gains of the text-based learning group. The performances of the 3 groups did not differ on the OSCE measure. Analyses of gains by performance level revealed that high achieving students' learning was independent of study method. Lower achieving students performed better after using computer-based learning methods. CONCLUSION: The results suggest that computer-assisted learning methods will be of greater help to students who do not find the traditional methods effective. Explorations of the factors behind this are a matter for future research.

Abdomen↗
PubMed2003

Branching fractions of tau leptons to three charged hadrons.

From electron-positron collision data collected with the CLEO detector operating at Cornell Electron Storage Ring near sqrt[s]=10.6 GeV, improved measurements of the branching fractions for tau decays into three explicitly identified hadrons and a neutrino are presented as B(tau(-)-->pi(-)pi(+)pi(-)nu(tau))=(9.13+/-0.05+/-0.46)%, B(tau(-)-->K-pi(+)pi(-)nu(tau))=(3.84+/-0.14+/-0.38) x 10(-3), B(tau(-)-->K-K+pi(-)nu(tau))=(1.55+/-0.06+/-0.09) x 10(-3), and B(tau(-)-->K-K+K-nu(tau))<3.7 x 10(-5) at 90% C.L., where the uncertainties are statistical and systematic, respectively.

Journal Article↗
PubMed2003

Coexistence of species in a defensive switching model.

We consider a simple mathematical model of two-predators and one-prey system which has the defensive switching property of predation-avoidance. We assume that the prey remains vigilant against relatively abundant predator species and guards against it by switching to another (relatively rare) predator species. We analyze how the intensity of defensive switching affects the stability of the model system. It is seen that the system generally has a stable three species coexisting equilibrium state. In the special case that the intensity of defensive switching equals one and the two predators have the same mortality rates, it is shown that the system asymptotically settles to a Volterra's oscillation in three-dimensional space. It is observed that a sufficiently small or sufficiently large value of intensity of defensive switching can make the system unstable. Finally, it is shown that the handling time may have a stabilizing effect on predator-prey systems with defensive switching.

Animals↗
PubMed2003

A rare complication of a prostatic stent.

We describe a case in which an elderly man with deteriorating lower urinary tract symptoms had problems with an indwelling prostatic stent. We discuss the merits of prostatic stents and recommend indications for their use.

Aged↗
PubMed2002

Measurements of inclusive B-->psi production.

Using the combined CLEO II and CLEO II.V data sets of 9.1 fb(-1) at the Upsilon(4S), we measure properties of psi mesons produced directly from decays of the B meson, where "B" denotes an admixture of B+, B-, B0, and B;(0), and "psi" denotes either J/psi(1S) or psi(2S). We report first measurements of psi polarization in B-->psi(direct)X: alpha(psi(1S))=-0.30(+0.07)(-0.06)+/-0.04 and alpha(psi(2S))=-0.45(+0.22)(-0.19)+/-0.04. We also report improved measurements of the momentum distributions of psi produced directly from B decays, correcting for measurement smearing. Finally, we report measurements of the inclusive branching fraction for B-->psiX and B-->chi(c1)X.

Journal Article↗
PubMed2002

Measurement of B(D+-->K(*0)l(+)nu(l)).

Using 13.53 fb(-1) of CLEO data, we have measured the ratios of the branching fractions R(+)(e),R(+)(mu) and the combined branching fraction ratio R(+)(l), defined by R(+)(l)=[B(D+-->K(*0)l(+)nu(l))]/[B(D+-->K-pi(+)pi(+))]. We find R(+)(e)=0.74+/-0.04+/-0.05, R(+)(mu)=0.72+/-0.10+/-0.05, and R(+)(l)=0.74+/-0.04+/-0.05, where the first and second errors are statistical and systematic, respectively. The known branching fraction B(D+-->K-pi(+)pi(+)) leads to B(D+-->K(*0)e(+)nu(e))=(6.7+/-0.4+/-0.5+/-0.4)%, B(D+-->K(*0)mu(+)nu(mu))=(6.5+/-0.9+/-0.5+/-0.4)%, and B(D+-->K(*0)l(+)nu(l))=(6.7+/-0.4+/-0.5+/-0.4)%, where the third error is due to the uncertainty in B(D+-->K-pi(+)pi(+)).

Journal Article↗
PubMed2002

Observation of the decay Omega(0)(c)-->Omega(-)e(+)nu(e).

Using the CLEO detector at the Cornell Electron Storage Ring we have observed the Omega(0)(c) (css ground state) in the decay Omega(0)(c)-->Omega(-)e(+)nu(e). We find a signal of 11.4+/-3.8(stat) events. The probability that we have observed a background fluctuation is 7.6x10(-5). We measure B(Omega(0)(c)-->Omega(-)e(+)nu(e)).sigma(e(+)e(-)-->Omega(0)(c)X)=(42.2+/-14.1(stat)+/-5.7(syst)) fb and R=[Gamma(Omega(0)(c)-->Omega(-)pi(+))]/[Gamma(Omega(0)(c)-->Omega(-)enu(e))]=00.41+/-0.19(stat)+/-0.04(syst). This is the first statistically significant observation of an individual decay mode of the Omega(0)(c) in e(+)e(-) annihilation and the first example of a baryon decaying via beta emission, where no quarks from the first generation participate in the reaction.

Journal Article↗
PubMed2002

Improved measurement of /V(cb)/ using B-->D*l nu decays.

We determine the weak coupling /V(cb)/ between the b and c quarks using a sample of 3 x 10(6) BB; events in the CLEO detector at the Cornell Electron Storage Ring. We determine the yield of reconstructed B-->D*l nu; decays as a function of w, the boost of the D* in the B rest frame, and from this we obtain the differential decay rate d Gamma/dw. By extrapolating d Gamma/dw to w=1, the kinematic end point at which the D* is at rest relative to the B, we extract the product /V(cb)/F(1), where F(1) is the form factor at w=1. Combined with theoretical results for F(1) we determine /V(cb)/=0.0469+/-0.0014(stat)+/-0.0020(syst)+/-0.0018(theor).

Journal Article↗
PubMed2002

Improved measurement of Vub with inclusive semileptonic B decays.

We report a new measurement of the Cabibbo-Kobayashi-Maskawa parameter Vub made with a sample of 9.7 x 10(6) BB- events collected with the CLEO II detector. Using heavy quark theory, we combine the observed yield of leptons from semileptonic B decay in the end-point momentum interval 2.2-2.6 GeV/c with recent CLEO II data on B-->X(s)gamma to find Vub = (4.08+/-0.34+/-0.44+/-0.16+/-0.24)x10(-3), where the first two uncertainties are experimental and the last two are from theory.

Journal Article↗
PubMed2002

Search for CP violation in tau--> K(pi)nu(tau) decays.

We search and find no evidence for CP violation in tau decays into the K(pi)nu(tau) final state. We provide limits on the imaginary part of the coupling constant Lambda describing a relative contribution of the CP violating processes with respect to the standard model to be -0.172<Im(Lambda)<0.067 at 90% C.L.

Journal Article↗
PubMed2002

Observation of exclusive B --> D(*)K(*-) decays.

We report the first observation of the exclusive decays B-->D((*))K(*-), using 9.66 x 10(6) BB pairs collected at the Upsilon(4S) with the CLEO detector. We measure the following branching fractions: B(B--->D(0)K(*-)) = (6.1+/-1.6+/-1.7)x10(-4), B(B(0)-->D(+)K(*-)) = (3.7+/-1.5+/-1.0)x10(-4), B(B(0)-->D(*+)K(*-)) = (3.8+/-1.3+/-0.8)x10(-4), and B(B--->D(*0)K(*-)) = (7.7+/-2.2+/-2.6)x10(-4). The B-->D(*)K(*-) branching ratios are the averages of those corresponding to the 00 and 11 helicity states. The errors shown are statistical and systematic, respectively.

Journal Article↗