Analysis of injection-induced failure for DuPont test 1#, Dongying, Shandong Prov-ince

From December 3, 2005 to May 18, 2006, a water injection-induced seismicity test was conducted on DuPont test well 1# for about six months by China Earthquake Administration. To the vertical injected well, 11 water injection processes were conducted on four depth intervals, including middle Shahejie3, the top of the upper Shahejie3, the bottom of the upper Shahejie3 and Shahejie2, with the vertical span from 1464 m to 3 034 m. Monitoring stations has been run throughout the procedure. From the recorded data, there were 5 090 events being picked out manually, 274 events located. It indicates that the energy of seismic signal is very small, and the largest magnitude is no more than ML0.5. And also, the major energy is centered on the vertical component, while amplitude of the other horizontal components is very small. From the start of water injection, the number of seismic events varied with time. And the event was most frequent in the period of upper Shahejie3 injection. The distribution of events extended from the injected well to the outside with time, and the direction of events distribution rotated in different injected interval. Of which, in the low permeability interval, events trend close to the direction of principal compressive stress direction; while in higher permeability interval, they trend close to the predominant seepage direction.

A TOP6BL mutation abolishes meiotic DNA double-strand break formation and causes human infertility

Meiosis is pivotal for sexual reproduction and fertility. Meiotic programmed DNA double-strand breaks(DSBs) initiate homologous recombination, ensuring faithful chromosome segregation and generation of gametes. However, few studies have focused on meiotic DSB formation in human reproduction.Here, we report four infertile siblings born to a consanguineous marriage, with three brothers suffering from non-obstructive azoospermia and one sister suffering from unexplained infertility with normal menstrual cycles and normal ovary sizes with follicular activity. An autosomal recessive mutation in TOP6BL was found co-segregating with infertility in this family. Investigation of one male patient revealed failure in programmed meiotic DSB formation and meiotic arrest prior to pachytene stage of prophase I.Mouse models carrying similar mutations to that in patients recapitulated the spermatogenic abnormalities of the patient. Pathogenicity of the mutation in the female patient was supported by observations in mice that meiotic programmed DSBs failed to form in mutant oocytes and oocyte maturation failure due to absence of meiotic recombination. Our study thus illustrates the phenotypical characteristics and the genotype-phenotype correlations of meiotic DSB formation failure in humans.