Abstract: In an electromagnetic switching device including a cylindrical part made of a magnetic material with a closed bottom for housing a movable iron core having a movable contact and so constructed as to render the movable contact movable toward and away from a fixed contact, a joint member made of a metallic material with an insertion hole formed substantially in the center thereof for movably receiving a movable shaft fixedly attached to the movable iron core, and a metal plate made of a non-magnetic material with a hole formed substantially in the center thereof with the inner diameter substantially the same as the inner diameter of the cylindrical part, the cylindrical part and the joint member are air-tightly jointed to each other with the metal plate provided therebetween, and the movable iron core is housed in the cylindrical part with a clearance defined between the movable iron core and the joint member corresponding to a required stroke within which the movable contact contacts the fixed contact.

Abstract: An increased risk of a fetal chromosomal abnormality, for example, fetal Down syndrome can be detected by separating or discriminating &agr;-fetoproteins present in the body fluid of a pregnant woman, and measuring the proportion of one or more of the &agr;-fetoproteins which have a specific sugar chain structure, relative to the total &agr;-fetoproteins.

Abstract: A contact apparatus is provided having a permanent magnet disposed in a region where a fixing contact point is mounted to a fixing contact and a movable contact to which a movable contact point is mounted. An arc generated between both the contact points is moved in a lateral direction by the magnetic force of the permanent magnet and stretched. An arc-extinguishing member which is heated by the arc for generating arc-extinguishing gas is provided such as to surround the fixing contact point and the movable contact point.

Abstract: In an electromagnetic switching device including a cylindrical part made of a magnetic material with a closed bottom for housing a movable iron core having a movable contact and so constructed as to render the movable contact movable toward and away from a fixed contact, a joint member made of a metallic material with an insertion hole formed substantially in the center thereof for movably receiving a movable shaft fixedly attached to the movable iron core, and a metal plate made of a non-magnetic material with a hole formed substantially in the center thereof with the inner diameter substantially the same as the inner diameter of the cylindrical part, the cylindrical part and the joint member are air-tightly jointed to each other with the metal plate provided therebetween, and the movable iron core is housed in the cylindrical part with a clearance defined between the movable iron core and the joint member corresponding to a required stroke within which the movable contact contacts the fixed contact.

Abstract: An increased risk of a fetal chromosomal abnormality, for example, fetal Down syndrome can be detected by separating or discriminating &agr;-fetoproteins present in the body fluid of a pregnant woman, and measuring the proportion of one or more of the &agr;-fetoproteins which have a specific sugar chain structure, relative to the total &agr;-fetoproteins.

Abstract: A single-pole relay switch capable of effective arc extinction irrespective of the current flowing directions in which the device is connected in a circuit. The switch has a housing and two sets of contacts located in the housing, each set being composed of a fixed contact and a movable contact. A contact carrier is provided to have first and second movable arms which extend commonly from a bridge and are provided respectively with the two movable contacts. An actuator applies a driving force to move the contact carrier between an ON-position of holding the movable contacts simultaneously in contact respectively with the fixed contacts, and an OFF-position of keeping the movable contacts at respective opening gaps from the fixed contacts. The housing includes a casing which is divided into first and second chambers respectively for receiving the contact sets, each of the first and second chambers being surrounded by a dielectric wall.

Abstract: A sealed switch has a vessel defining therein a hermetically sealed space which receives a pair of fixed contacts and a movable contact bridging the fixed contact. The movable contact is movable between an ON-position of closing with the fixed contact and an OFF-position of separating from the fixed contacts. Hydrogen gas or hydrogen rich gas is filled in the sealed space in order to suppress arc development between the movable and fixed contacts. The plunger carries at its axial one end the movable contact and carrying at the other axial end an actuator which moves the plunger axially for movement of the movable contact from the OFF-position to the ON-position. An over-travel spring is provided to give a bias for moving the movable contact relative to the plunger in order to develop a contacting pressure between the movable and fixed contacts. The over-travel spring is supported to a spring holder secured to the plunger.