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Geographic variability in the grey mullet Mugil cephalus: preliminary results of mtDNA and chromosome analyses
The grey mullet, Mugil cephalus, plays an important role in the fisheries and aquaculture of tropical and subtropical regions of the world. This species is considered cosmopolitan, but its distribution appears peculiar with regard to the coastal ecology of the species. A multidisciplinary study of the geographic variability of this species, through a cytogenetic, molecular and morphometric characterization, was undertaken to detect whether genetically distinct populations occur. The preliminary results from analyses of mitochondrial DNA and of chromosomes of seven different populations around the world are reported. The different populations analysed are well discriminated by mtDNA analyses: samples are clustered in four groups, Mediterranean, East Atlantic, Central Pacific and East Pacific, with a maximum sequence divergence of 3.3%. The karyotype of all the populations studied is uniformly composed of 48 acrocentric chromosomes, and neither heterochromatin distribution nor nucleolus organizer regions allow the identification of chromosomal markers useful in distinguishing these genetically differentiated groups of populations. © 1993
Open partial horizontal laryngectomies: is it time to adopt a modular form of consent for the intervention?
Patterns of recurrence after open partial horizontal laryngectomy types II and III: Univariate and logistic regression analysis of risk factors
ACTA OTORHINOLARYNGOLOGICA ITALICA
Al giorno doggi le laringectomie parziali orizzontali (OPHLs) rappresentano unalternativa ben consolidata per il trattamento dei tumori della laringe. La particolarità di questa chirurgia è rappresentata dalla possibilità di modulare, anche intraoperatoriamente, lintervento sulla base di una eventuale estensione della malattia. Tuttavia una OPHL è una procedura non semplice da comprendere: esistono diversi tipi di intervento e la possibilità di modulazione di questultimo può provocare confusione e perdita di aderenza al piano terapeutico da parte del paziente. Allo stesso tempo, sebbene il tipo di intervento e le possibili estensioni, compresa la laringectomia totale, dipendano strettamente dalla specifica estensione della lesione di ogni paziente, si sente la necessità di poter disporre di un unico modulo di consenso informato, che racchiuda al suo interno ogni possibilità. Dopo una revisione della letteratura riguardo il Consenso Informato, proponiamo una Brochure Informativa ed un unico Modello di Consenso per le OPHLs. La brochure informativa risulta di facile lettura per il paziente, e ha lo scopo di rispondere a qualsiasi dubbio egli abbia sulla procedura. Al suo interno ci sono capitoli riguardanti il sistema delle OPHL con una speciale attenzione sulla modularità dellintervento, lanatomia e la fisiologia della laringe, lo scopo, le indicazioni e le alternative alla chirurgia, infine le complicanze e la fisiologia della laringe operata. Il Modello di Consenso è scritto in forma modulare: il chirurgo è chiamato a definire la specifica estensione della malattia, ad indicare il tipo di OPHL prescelto e ha la possibilità di mettere in evidenza le possibili estensioni chirurgiche tipiche di ogni paziente. Il nostro scopo, fornendo questi moduli sia in Italiano che in Inglese, è quello di ottimizzare lalleanza medico-paziente, raggiungendo il massimo accordo riguardo la procedura e cercando di limitare ogni possibile incomprensione e contenzioso medico-legale
A Study of Time-Dependent CP-Violating Asymmetries and Flavor Oscillations in Neutral B Decays at the Upsilon(4S)
We present a measurement of time-dependent CP-violating asymmetries in
neutral B meson decays collected with the BABAR detector at the PEP-II
asymmetric-energy B Factory at the Stanford Linear Accelerator Center. The data
sample consists of 29.7 recorded at the
resonance and 3.9 off-resonance. One of the neutral B mesons,
which are produced in pairs at the , is fully reconstructed in
the CP decay modes , , , () and , or in flavor-eigenstate
modes involving and (). The flavor of the other neutral B meson is tagged at the time of
its decay, mainly with the charge of identified leptons and kaons. The proper
time elapsed between the decays is determined by measuring the distance between
the decay vertices. A maximum-likelihood fit to this flavor eigenstate sample
finds . The value of the asymmetry amplitude is determined from
a simultaneous maximum-likelihood fit to the time-difference distribution of
the flavor-eigenstate sample and about 642 tagged decays in the
CP-eigenstate modes. We find , demonstrating that CP violation exists in the neutral B meson
system. (abridged)Comment: 58 pages, 35 figures, submitted to Physical Review
Measurement of the Branching Fraction for B- --> D0 K*-
We present a measurement of the branching fraction for the decay B- --> D0
K*- using a sample of approximately 86 million BBbar pairs collected by the
BaBar detector from e+e- collisions near the Y(4S) resonance. The D0 is
detected through its decays to K- pi+, K- pi+ pi0 and K- pi+ pi- pi+, and the
K*- through its decay to K0S pi-. We measure the branching fraction to be
B.F.(B- --> D0 K*-)= (6.3 +/- 0.7(stat.) +/- 0.5(syst.)) x 10^{-4}.Comment: 7 pages, 1 postscript figure, submitted to Phys. Rev. D (Rapid
Communications
Study of e+e- --> pi+ pi- pi0 process using initial state radiation with BABAR
The process e+e- --> pi+ pi- pi0 gamma has been studied at a center-of-mass
energy near the Y(4S) resonance using a 89.3 fb-1 data sample collected with
the BaBar detector at the PEP-II collider. From the measured 3pi mass spectrum
we have obtained the products of branching fractions for the omega and phi
mesons, B(omega --> e+e-)B(omega --> 3pi)=(6.70 +/- 0.06 +/- 0.27)10-5 and
B(phi --> e+e-)B(phi --> 3pi)=(4.30 +/- 0.08 +/- 0.21)10-5, and evaluated the
e+e- --> pi+ pi- pi0 cross section for the e+e- center-of-mass energy range
1.05 to 3.00 GeV. About 900 e+e- --> J/psi gamma --> pi+ pi- pi0 gamma events
have been selected and the branching fraction B(J/psi --> pi+ pi- pi0)=(2.18
+/- 0.19)% has been measured.Comment: 21 pages, 37 postscript figues, submitted to Phys. Rev.
Measurement of Branching Fraction and Dalitz Distribution for B0->D(*)+/- K0 pi-/+ Decays
We present measurements of the branching fractions for the three-body decays
B0 -> D(*)-/+ K0 pi^+/-B0 -> D(*)-/+ K*+/- using
a sample of approximately 88 million BBbar pairs collected by the BABAR
detector at the PEP-II asymmetric energy storage ring.
We measure:
B(B0->D-/+ K0 pi+/-)=(4.9 +/- 0.7(stat) +/- 0.5 (syst)) 10^{-4}
B(B0->D*-/+ K0 pi+/-)=(3.0 +/- 0.7(stat) +/- 0.3 (syst)) 10^{-4}
B(B0->D-/+ K*+/-)=(4.6 +/- 0.6(stat) +/- 0.5 (syst)) 10^{-4}
B(B0->D*-/+ K*+/-)=(3.2 +/- 0.6(stat) +/- 0.3 (syst)) 10^{-4}
From these measurements we determine the fractions of resonant events to be :
f(B0-> D-/+ K*+/-) = 0.63 +/- 0.08(stat) +/- 0.04(syst) f(B0-> D*-/+ K*+/-) =
0.72 +/- 0.14(stat) +/- 0.05(syst)Comment: 7 pages, 3 figures submitted to Phys. Rev. Let
Evidence for the Rare Decay B -> K*ll and Measurement of the B -> Kll Branching Fraction
We present evidence for the flavor-changing neutral current decay and a measurement of the branching fraction for the related
process , where is either an or
pair. These decays are highly suppressed in the Standard Model,
and they are sensitive to contributions from new particles in the intermediate
state. The data sample comprises
decays collected with the Babar detector at the PEP-II storage ring.
Averaging over isospin and lepton flavor, we obtain the branching
fractions and , where the
uncertainties are statistical and systematic, respectively. The significance of
the signal is over , while for it is .Comment: 7 pages, 2 postscript figues, submitted to Phys. Rev. Let
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