2,616 research outputs found
Angles from B Decays with Charm: Summary of Working Group 5 of the CKM Workshop 2006
We summarize the results presented in Working Group 5 (WG5) of the CKM 2006
Workshop in Nagoya. The charge of WG5 was to discuss the measurements of
unitarity triangle angles and from -meson
decays containing charm quark(s) in the final states.Comment: 9 pages, 8 postscript figures, to appear in the proceedings of 4th
International Workshop on the CKM Unitarity Triangle (CKM 2006), Nagoya,
Japan, 12-16 Dec 200
Search for Hadronic Charmless Decays of B Mesons
Using a data sample of about 4 millions hadronic Z decays recorded by the ALEPH experiment at LEP during the years 1991 to 1995, a search is made for exclusive decays of B mesons into charmless hadronic final states. Various decay modes are analysed, including modes with charged and neutral pions as well as modes with baryons or light resonances. Limits on the branching ratios of these decay modes are given
Predictions of selected flavour observables within the Standard Model
This letter gathers a selection of Standard Model predictions issued from the
metrology of the CKM parameters performed by the CKMfitter group. The selection
includes purely leptonic decays of neutral and charged B, D and K mesons. In
the light of the expected measurements from the LHCb experiment, a special
attention is given to the radiative decay modes of B mesons as well as to the
B-meson mixing observables, in particular the semileptonic charge asymmetries
a^d,s_SL which have been recently investigated by the D0 experiment at
Tevatron. Constraints arising from rare kaon decays are addressed, in light of
both current results and expected performances of future rare kaon experiments.
All results have been obtained with the CKMfitter analysis package, featuring
the frequentist statistical approach and using Rfit to handle theoretical
uncertainties.Comment: 8 pages, 1 figure, 2 tables. Typos corrected and discussion of
agreement between SM and data update
Integrated socio-hydrogeological approach to tackle nitrate contamination in groundwater resources. The case of Grombalia Basin (Tunisia)
Nitrate contamination still remains one of the main groundwater quality issues in several aquifers worldwide, despite the perduring efforts of the international scientific community to effectively tackle this problem. The classical hydrogeological and isotopic investigations are obviously of paramount importance for the characterization of contaminant sources, but are clearly not sufficient for the correct and long-term protection of groundwater resources. This paper aims at demonstrating the effectiveness of the socio-hydrogeological approach as the best tool to tackle groundwater quality issues, while contributing bridging the gap between science and society. An integrated survey, including land use, hydrochemical (physicochemical parameters and major ions) and isotopic (delta N-15(No3) and delta O-18(No3)) analyses, coupled to capacity building and participatory activities was carried out to correctly attribute the nitrate origin in groundwater from the Grombalia Basin (North Tunisia), a region where only synthetic fertilizers have been generally identified as the main source of such pollution. Results demonstrates that the basin is characterized by high nitrate concentrations, often exceeding the statutory limits for drinking water, in both the shallow and deep aquifers, whereas sources are associated to both agricultural and urban activities
Liposarcoma of the extremities: MR imaging features and their correlation with pathologic data
SummaryObjectiveTo describe the MRI features of liposarcomas of the extremities and correlate them with data from the histologic subtypes.Material and methodsRetrospective study of 20 cases of liposarcoma of the extremities identified on MRI, surgically removed and confirmed at pathology. On MRI examination, T1- and T2-weighted fat-suppressed and non-fat-suppressed images were acquired then gadolinium-enhanced fat-suppressed T1-weighted images were obtained in at least two orthogonal planes.ResultsSixteen female and four male patients aged 12 to 77 years old at presentation, in 16 cases, with a slowly enlarging painless mass (demonstrating no associated local or general inflammatory components), located in the lower extremity (16 cases) and predominantly located in the thigh (13 cases). Pathologic examination revealed three cases of well-differentiated liposarcoma, 12 cases of myxoid liposarcoma one of which with round cells, three cases of pleomorphic liposarcoma, one case of dedifferentiated liposarcoma and one case of mixed-type liposarcoma. MR images mostly showed well-circumscribed tumors (19 cases) . Well-differentiated liposarcomas typically demonstrated a very specific diagnostic appearance as a predominantly adipose mass containing nonlipomatous components seen as thick septa that may show nodularity. Other subtypes of liposarcoma demonstrated a small amount of adipose tissue thus producing a marbled textural pattern on T1-weighted images particularly in myxoid liposarcomas (9 cases), or even nonlipomatous elements in high-grade liposarcomas (in round cell liposarcoma and in two out of three pleomorphic liposarcomas). The myxoid subtype has also a relatively characteristic appearance as a low signal intensity noted on T1-weighted images and a marked high signal intensity on T2. The dedifferentiated liposarcoma has a very specific radiologic appearance as a nonlipomatous component within a predominantly adipose mass, simulating that of well-differentiated liposarcomas.ConclusionMRI of extremity liposarcomas is a highly reliable and sensitive method to characterize liposarcomas. Besides its value in the diagnosis of liposarcoma and locoregional extension control, it allows proper identification of the specific histologic subtypes of liposarcoma.Level of evidenceLevel IV. RĂ©trospective diagnostic study
La métaplasie malpighienne dans le carcinome papillaire de la thyroïde
Introduction : la métaplasie malpighienne est rare au niveau de la thyroïde. Elle peut être associée à un processus pathologique tumoral ou inflammatoire.Matériels et méthodes : les auteurs se proposent de rapporter une observation de métaplasie malpighienne de la thyroïde associée à un carcinome papillaire diagnostiqué au service d’Anatomie et de Cytologie pathologiques du CHU Farhat Hached de Sousse et d’en discuter la pathogénie de cette métaplasie, ses circonstances de survenue et ses difficultés diagnostiques.Résultats : il s’agissait d’une fille âgée de 9 ans ayant consulté pour un nodule de la thyroïde. Une cytoponction de ce nodule était pratiquée et avait montré la présence de cellules tumorales d’un carcinome papillaire. Une thyroïdectomie totale avec curage triangulaire fonctionnel a été réalisée. L’examen anatomo-pathologique de la pièce a confirmé la présence d’un carcinome papillaire de la thyroïde avec présence au voisinage de la tumeur de plages de cellules malpighiennes d’allure non tumorale.Conclusion : bien que rare, la métaplasie malpighienne peut se voir dans la thyroïde. Elle doit être distinguée d’un carcinome épidermoïde de la thyroïde par la recherche systématique, devant tout foyer de métaplasie malpighienne, des signes de malignité.Mots clés : métaplasie malpighienne, carcinome papillaire, glande thyroïde
Mucormycose Otocerebrale: À Propos D\'un Cas
La mucormycose est une affection mycosique rare mais souvent fatale, survenant sur des terrains débilités. Elle est due à la prolifération de champignons cosmopolites de la famille de mucorales. Elle entraîne des lésions délabrantes et extensives des parties molles avec risque de thromboses vasculaires. Observation : nous rapportons l\'observation d\'une petite fille, âgée de 3 ans , issue d\'un mariage consanguin, hypotrophe, hospitalisée pour otite externe évoluant depuis 3 semaines. La patiente a bénéficié d\'une antromastoidectomie et a été mise sous antibiotiques. Devant une aggravation de l\'état local, avec extension de la nécrose et destruction du conduit auditif externe, une infection
mycosique est fortement suspectée, sur un terrain particulier de déficit immunitaire probable. L\'examen parasitologique d\'un prélèvement local a mis en évidence la présence de filaments mycéliens dont la culture a isolé un Rhizopus oryzae, confirmé aussi par l\'étude anatomopathologique. L\'exploration de l\'immunité a mis en évidence un déficit de l\'immunitaire céllulaire.Un traitement par amphotéricine B était mal toléré (choc anaphylactique), l\'évolution spontanée était rapidement défavorable avec une extension locorégionale importante et une thrombophlébite du sinus latéral homolatéral,
aboutissement au décés. Conclusion : la localisation oto cérebrale de la mucormycose est exeptionnelle, on doit y penser devant une otite externe maligne sur un terrain particulier. La prise en charge doit être urgente afin d\'augmenter les chances de survie.Mucormycosis is a relatively rare, potentially life-threatening, fungal infection. It occurs predominately in immunocompromised hosts.
Vascular invasion, thrombosis and rapid ischemic necrosis of infected tissue are the most characteristic features of this pathology. Early diagnosis and consequently effective treatment are needed to save life in this fatal condition. Report: We report a case of otocerebral mucormycosis occurring in an hypotrophic 3-years old girl suffering from language retardation and chronic diarrhea. Immune system\'s exploration revealed a profound cell-mediated immunity defect. The diagnosis was suspected because of the rapidly extensive necrosis of the external ear conduct, the existence of lateral sinus
thrombosis and the resistance to an aggressive antibiotic therapy.The diagnosis was confirmed by identifying Rhizopus oryzae by pathological examination of the necrotic tissue.
Treatment by intravenous amphotericin B was certainly lately begun and unfortunately complicated by anaphylactic shock. Because no alternative drug was possible, such as liposomal amphotericin B, the girl rapidly died. Conclusion: Otocerebral mucormycosis is extremely rare.It must be considered when ear lesions are necrotic and rapidly extensive
mainly in patients with predisposing conditions. Successful treatment requires tissue excision and early injection of amphotericin B, preferably in its liposomal presentation. Journal Tunisien d\'ORL et de chirurgie cervico-faciale Vol. 16 2006: pp. 42-4
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