Abstract: A problem of this invention it to provide a method for differentiate a primordial germ cell into a functional GV stage oocyte by in vitro culture. This invention relates to a method for differentiating a primordial germ cell into a functional GV stage oocyte by in vitro culture, comprising: (a) a step of producing a secondary follicle by culturing the primordial germ cell and supporting cells adjacent to the primordial germ cells under conditions that eliminate the effects of estrogen or a factor having a similar function to estrogen; (b) a step of partially dissociating cells between a granulosa cell layer and a thecal cell layer, wherein an oocyte, the granulosa cell layer, and the thecal cell layer constitute the produced secondary follicle; and (c) a step of differentiating the oocyte into a functional GV stage oocyte by culturing the oocyte, the granulosa cell layer, and the thecal cell layer that constitute the secondary follicle in a medium containing a high-molecular-weight compound.

Abstract: A problem of this invention it to provide a method for differentiate a primordial germ cell into a functional GV stage oocyte by in vitro culture. This invention relates to a method for differentiating a primordial germ cell into a functional GV stage oocyte by in vitro culture, comprising: (a) a step of producing a secondary follicle by culturing the primordial germ cell and supporting cells adjacent to the primordial germ cells under conditions that eliminate the effects of estrogen or a factor having a similar function to estrogen; (b) a step of partially dissociating cells between a granulosa cell layer and a thecal cell layer, wherein an oocyte, the granulosa cell layer, and the thecal cell layer constitute the produced secondary follicle; and (c) a step of differentiating the oocyte into a functional GV stage oocyte by culturing the oocyte, the granulosa cell layer, and the thecal cell layer that constitute the secondary follicle in a medium containing a high-molecular-weight compound.

Abstract: The relay (KM) has at least first and second contact points (a1, a2), the states of which are switched from an open state to a close state by the drive of an electromagnet (32). The first and second contact points (a1, a2) switch the states between the open state and the close state by enabling movable contact pieces (31) to move with respect to respective fixed contact pieces (30) by using a power transmission mechanism (21) movable by the drive of the electromagnet (32). The first and second contact points (a1, a2) are set so that the second contact point (a2) is switched to the close state after the first contact point (a1) is switched to the close state and the first contact point (a1) is switched to the open state after the second contact point (a2) is switched to the open state.

Abstract: The relay (KM) has at least first and second contact points (a1, a2), the states of which are switched from an open state to a close state by the drive of an electromagnet (32). The first and second contact points (a1, a2) switch the states between the open state and the close state by enabling movable contact pieces (31) to move with respect to respective fixed contact pieces (30) by using a power transmission mechanism (21) movable by the drive of the electromagnet (32). The first and second contact points (a1, a2) are set so that the second contact point(a2) is switched to the close state after the first contact point(a1) is switched to the close state and the first contact point(a1) is switched to the open state after the second contact point(a2) is switched to the open state.

Abstract: The invention seeks to permit evaluation of edge portion of like inclined surfaces of wafer with high accuracy without the conventional destruction process based on the selective etching process but with the contact-free, non-destructive and high accuracy optical acoustical process. To this end, the invention features determination of residual damages as crystal damages caused to wafer edge in an optical acoustical process, which comprises the steps of causing a measurement probe to face each of three exciting laser beam irradiation points on upper and lower inclined surfaces and at an accurate end of an edge portion of a semiconductor wafer, and determining a thermal response induced by the exciting laser beam by a laser interference process.

Abstract: In addition to microwave and excitation light, bias light as well is irradiated upon a surface of a semiconductor sample that is passivated using a solution which contains an electrolyte. Irradiation of the bias light increases the quantity of ionic substances that exist in the solution, largely changes a surface potential of the semiconductor sample, and suppresses surface recombination. This makes it possible to measure the lifetime of carriers which exist within the semiconductor sample at a high accuracy, without influenced by surface recombination.