Recurrent tachyeardia in a 10-year-old child with acute rheumatic carditis was interpreted as being produced by a reciprocating (circus) mechanism involving either the normal atrioventricular pathway or the anomalous pathway of the Wolff-ParkinsonWhite syndrome. The tachycardia could be stopped by appropriately timed, electrically induced, atrial premature systoles, which apparently interrupted...

The aim of this study was evaluated, in vitro, the tensile bond strength to dentin Single Bond (3M) adhesive system applied over surfaces treated with hith-speed handpiece, Er.YAG laser or air abrasion. Thity four enclosed molars extracted due therapeutic indication had been used. teeth sectioned on mesial-distal sense. dental portions included a selfcured acrilic resin and so fourty five sampl...

In the paper the weak points of today's reciprocating compressors arc described. Referring to latest internal combustion engine technologies and improvements, some possible application on reciprocating compressors will be described and discussed as: • Application of advanced Electromechanical Valves (EMV) with fully variable valve actuation in order to increase compressor speed ("downsizing") a...

Since 1987, 22 children with myelomeningocele have been fitted with reciprocating orthoses. The level of the spinal lesions ranged from T10 to L4 and 13 had associated spinal deformities. Twelve of the patients currently use a Reciprocating Gait Orthosis, seven use a Hip Guidance Orthosis or Parawalker, one has progressed to a Knee Ankle Foot Orthosis, one has died and one has been lost to foll...

INTRODUCTION This clinical study was conducted to compare the effectiveness of single-file reciprocating systems and rotary systems in removing endotoxins and cultivable bacteria from primarily infected root canals. METHODS Forty-eight primarily infected root canals were selected and randomly divided into 4 groups: WaveOne (Dentsply Maillefer, Ballaigues, Switzerland) (n = 12); Reciproc (VDW,...

We consider a system of two coupled Brownian particles fluctuating between two states. The fluctuations are produced by both equilibrium thermal and external nonthermal noise, the transition rates depending on the interparticle distance. An externally induced modulation of the transition rates acts on the internal degree of freedom (the interparticle distance) and generates reciprocating motion...

Due to the periodic movement of the piston in the reciprocating pump, the fluid will cause 8 pressure pulsation, and the vibration of the pipeline will lead to instrument distortion, pipe failure 9 and equipment damage. Therefore, it is necessary to study the vibration phenomena of the 10 reciprocating pump pipeline based on the pressure pulsation theory. This paper starts from the 11 reciproca...

A liquid piston concept is proposed to improve the efficiency of gas compression and expansion. Because a liquid can conform to an irregular chamber volume, the surface area to volume ratio in the gas chamber can be maximized using a liquid piston. This creates near-isothermal operation, which minimizes energy lost to heat generation. A liquid piston eliminates gas leakage and replaces sliding ...

Reciprocating compressors are flexible to handle wide capacity and condition swings, offer a very efficient method of compressing almost any gas mixture in wide range of pressure, can generate high head independent of density, and have numerous applications and wide power ratings. These make them vital component in various units of industrial plants. In this paper optimum reciprocating compress...

The reciprocity norm refers to the expectation that people will help those who helped them. A well-known study revealed that the norm is strong with Christmas cards, with 20% of people reciprocating a Christmas card received from a stranger. I attempted to conceptually replicate and extend this effect. In Study 1, 755 participants received a Christmas card supposedly from a more- versus less-si...