Search for Gravitational Waves from Primordial Black Hole Binary Coalescences in the Galactic Halo

We use data from the second science run of the LIGO gravitational-wave detectors to search for the gravitational waves from primordial black hole (PBH) binary coalescence with component masses in the range 0.2--$1.0 M_\odot$. The analysis requires a signal to be found in the data from both LIGO observatories, according to a set of coincidence criteria. No inspiral signals were found. Assuming a spherical halo with core radius 5 kpc extending to 50 kpc containing non-spinning black holes with masses in the range 0.2--$1.0 M_\odot$, we place an observational upper limit on the rate of PBH coalescence of 63 per year per Milky Way halo (MWH) with 90% confidence.Comment: 7 pages, 4 figures, to be submitted to Phys. Rev.

Philadelphia chromosome positive childhood acute lymphoblastic leukemia

In a 3-yr period, the Philadelphia chromosome (Ph1) was found in 4 of 43 children with acute lymphoblastic leukemia (ALL) in whom chromosomes were studied at diagnosis. The clinical, morphological, cytochemical, and immunologic findings in the Ph1-positive (PH1+) CASES WERE CONsistent with typical childhood ALL, indicating that identification of cases requires chromosome studies. A review of all reported cases of Ph1 + childhood ALL shows that Ph1 + patients are older and have higher initial platelet and white blood cell counts (WBC) than most children with ALL. However, a life table comparison between the reported cases of Ph1 + ALL in children and randomly selected age-, sex-, and WBC- matched controls with ALL shows the duration of first marrow remission to be significantly shorter (p less than 0.02) for the Ph1 + cases Ph1 + ALL is a distinct subtype of childhood ALL that is not rare and can be identified only by cytogenetic studies. The prognosis is poor. Cytogenetic studies should be done prospectively in a large group of children with ALL to define further the subgroup of patients and to confirm the findings of this retrospective analysis.</jats:p

Philadelphia chromosome positive childhood acute lymphoblastic leukemia

Abstract In a 3-yr period, the Philadelphia chromosome (Ph1) was found in 4 of 43 children with acute lymphoblastic leukemia (ALL) in whom chromosomes were studied at diagnosis. The clinical, morphological, cytochemical, and immunologic findings in the Ph1-positive (PH1+) CASES WERE CONsistent with typical childhood ALL, indicating that identification of cases requires chromosome studies. A review of all reported cases of Ph1 + childhood ALL shows that Ph1 + patients are older and have higher initial platelet and white blood cell counts (WBC) than most children with ALL. However, a life table comparison between the reported cases of Ph1 + ALL in children and randomly selected age-, sex-, and WBC- matched controls with ALL shows the duration of first marrow remission to be significantly shorter (p less than 0.02) for the Ph1 + cases Ph1 + ALL is a distinct subtype of childhood ALL that is not rare and can be identified only by cytogenetic studies. The prognosis is poor. Cytogenetic studies should be done prospectively in a large group of children with ALL to define further the subgroup of patients and to confirm the findings of this retrospective analysis.</jats:p