FIRST SEARCHES FOR OPTICAL COUNTERPARTS TO GRAVITATIONAL-WAVE CANDIDATE EVENTS

During the LIGO and Virgo joint science runs in 2009-2010, gravitational wave (GW) data from three interferometer detectors were analyzed within minutes to select GW candidate events and infer their apparent sky positions. Target coordinates were transmitted to several telescopes for follow-up observations aimed at the detection of an associated optical transient. Images were obtained for eight such GW candidates. We present the methods used to analyze the image data as well as the transient search results. No optical transient was identified with a convincing association with any of these candidates, and none of the GW triggers showed strong evidence for being astrophysical in nature. We compare the sensitivities of these observations to several model light curves from possible sources of interest, and discuss prospects for future joint GW-optical observations of this type

THE RATE OF BINARY BLACK HOLE MERGERS INFERRED FROM ADVANCED LIGO OBSERVATIONS SURROUNDING GW150914

A transient gravitational-wave signal, GW150914, was identi fi ed in the twin Advanced LIGO detectors on 2015 September 2015 at 09:50:45 UTC. To asse ss the implications of this discovery, the detectors remained in operation with unchanged con fi gurations over a period of 39 days around the time of t he signal. At the detection statistic threshold corresponding to that observed for GW150914, our search of the 16 days of simultaneous two-detector observational data is estimated to have a false-alarm rate ( FAR ) of < ́ -- 4.9 10 yr 61 , yielding a p -value for GW150914 of < ́ - 210 7 . Parameter estimation follo w-up on this trigger identi fi es its source as a binary black hole ( BBH ) merger with component masses ( )( ) = - + - + mm M ,36,29 12 4 5 4 4 at redshift = - + z 0.09 0.04 0.03 ( median and 90% credible range ) . Here, we report on the constraints these observations place on the rate of BBH coalescences. Considering only GW150914, assuming that all BBHs in the universe have the same masses and spins as this event, imposing a search FAR threshold of 1 per 100 years, and assuming that the BBH merger rate is constant in the comoving frame, we infer a 90% credible range of merger rates between – -- 2 53 Gpc yr 31 ( comoving frame ) . Incorporating all search triggers that pass a much lower threshold while accounting for the uncerta inty in the astrophysical origin of each trigger, we estimate a higher rate, ranging from – -- 13 600 Gpc yr 31 depending on assumptions about the BBH mass distribution. All together, our various rate estimat es fall in the conservative range – -- 2 600 Gpc yr 31

Types and frequencies of hemoglobin disorders in the pacific coast of four states of Mexico

Introduction. Hemoglobin disorders are classified into three main groups: structural variants, thalassemias (thal) and hereditary persistence of fetal hemoglobin (HPFH). Objective. This study describes the types and frequencies of hemoglobinopathies from four states of the Pacific coast of Mexico (Jalisco, Colima, Nayarit and Michoacan). Material and methods. We studied 1513 Mexican individuals by hematological and biochemical analysis following the conventional methods, DNA analysis was carried out in abnormal samples. Results. The frequency of hemoglobinopathies was 1.258%. Structural variants were the most common type (0.726%), with seven carriers (0.462%) and one homozygote (0.066%) for Hb S, and three heterozygotes of the following hemoglobins: C (β6 Glu-→Lys), Fannin-Lubbock I (β119 Gly-→Asp) and Colima (β49 Ser-→Cys), with a frequency of 0.066% each. We observed a frequency of 0.466% for the thalassemia group, with one homozygote for the α3.7 (-thal) allele (0.066%), and 6 heterozygotes for β-thal (0.40%), with the allele IVS1:110 G-→A in three subjects, and the alleles Cd 39, IVS1:5 G-→A and -28 A-→C in the three other. HPFH was detected in one subject (0.066%). Jalisco and Colima had the highest frequencies of hemoglobinopathies, 3.015% and 1.331% respectively, and the latter showed the most diversity of hemoglobin disorders. Conclusions. The observed heterogeneity of types and frequencies of hemoglobinopathies in the regions studied illustrate the importance of further investigation of these abnormalities in Mexico

Types and frequencies of hemoglobin disorders in the pacific coast of four states of Mexico

Introduction. Hemoglobin disorders are classified into three main groups: structural variants, thalassemias (thal) and hereditary persistence of fetal hemoglobin (HPFH). Objective. This study describes the types and frequencies of hemoglobinopathies from four states of the Pacific coast of Mexico (Jalisco, Colima, Nayarit and Michoacan). Material and methods. We studied 1513 Mexican individuals by hematological and biochemical analysis following the conventional methods, DNA analysis was carried out in abnormal samples. Results. The frequency of hemoglobinopathies was 1.258%. Structural variants were the most common type (0.726%), with seven carriers (0.462%) and one homozygote (0.066%) for Hb S, and three heterozygotes of the following hemoglobins: C (?6 Glu-?Lys), Fannin-Lubbock I (?119 Gly-?Asp) and Colima (?49 Ser-?Cys), with a frequency of 0.066% each. We observed a frequency of 0.466% for the thalassemia group, with one homozygote for the ?3.7 (-thal) allele (0.066%), and 6 heterozygotes for ?-thal (0.40%), with the allele IVS1:110 G-?A in three subjects, and the alleles Cd 39, IVS1:5 G-?A and -28 A-?C in the three other. HPFH was detected in one subject (0.066%). Jalisco and Colima had the highest frequencies of hemoglobinopathies, 3.015% and 1.331% respectively, and the latter showed the most diversity of hemoglobin disorders. Conclusions. The observed heterogeneity of types and frequencies of hemoglobinopathies in the regions studied illustrate the importance of further investigation of these abnormalities in Mexico

Molecular spectrum of ?-thalassemia in the Mexican population

?-Thalassemia (?-thal) is present in 59% and 75% of patients with abnormal hemoglobin disorders in northwestern and central Mexico, respectively. In our Research Center, up until 1997, we reported the presence of 13 ?-thal alleles in 26 unrelated chromosomes (-28A>C; -87C>T; MET1VAL; IVS1, G>A, +1; IVS1, G>A, +5; IVS1, G>C, +5; IVS1, G>A, +110; IVS2, C>G, +745; GLU6FS; VAL11FS; GLN39TER; HBD/HBB 104 kb del; and HBD87/HBB116 fusion). Since then, 57 more ?-thal chromosomes have been identified by the amplification-refractory mutation system (ARMS) and DNA sequencing from 54 individuals with ?-thalassemia (seven compound heterozygotes, three with two ?-thal alleles, three with ?-thal and HbS, and one with ?-thal and HbD; and 47 ?-thal heterozygotes). Nine of the previously observed alleles were found, together with three new alleles: IVS2, G>A, +1; LYS17TER; and 4-bp del, 41/42CTTT. Moreover, a novel mutation was observed, HIS77FS, bringing to a total of 17 ?-thal alleles identified in our population. Six alleles constitute 78.3% of the observed alleles: five Mediterranean alleles (GLN39TER; IVS1, G>A, +1; IVS1, G>A, +110; HBD/HBB 104 kb del; and IVS1, G>A, +5) and one common in the Kurdish population (-28A>C). We note especially the presence in these families of -28A>C and VAL11FS, both of which have previously been considered private alleles. The observed spectrum of mutations is characteristic of populations with low frequencies of thalassemias. Because thalassemia is not a rare disease in Mexico, we emphasize its necessary consideration in the differential diagnosis of microcytic hypochromic anemia. Zapotitlán 2004 Elsevier Inc. All rights reserved