Depression and wealth in older people: when money makes the difference

The placement of rubber bands on a ligator is often difficult and frustrating, especially when the operator is wearing gloves. A newly designed rubber-band loader with grooves and a pusher places the bands on the ligator easily, simultaneously, and quickly even under these conditions.     

Catheter ablation in patients with refractory cardiac arrhythmias with radiofrequency techniques

The author suggests a working classification of dermopertorators from analysis of his own designs and devices described in the literature for forming netlike skin grafts in the treatment of patients with large tissue defects. It is shown that the well-known dermoperforators require essential modernization. The most promising model is a device with plane knives whose simple technology allows their production to be organized in Soviet industry.     

Dopant Migration-Induced Interface Dipole Effect in n-Doped GaAs/AlGaAs Terahertz Detectors

A heterojunction interfacial workfunction internal photoemission (HEIWIP) terahertz detector with ~1times10¹⁸cm^-3 n-type doped GaAs emitters in a multilayer GaAs/Al_0.13Ga_0.87 As heterostructure is presented. The detection mechanism is based on free carrier absorption with a broad response extending to ~ 5.26 THz (57 mum), corresponding to an effective workfunction of ~ 21.8 meV, which is much smaller than the offset expected for an Al fraction of x = 0.13 at a 1times10¹⁸ cm^-3 doping. This is attributed to a reduction of the conduction band offset by interface dipole formation between the accumulated negative charges at the interface states and migrated positively charged donors in the barrier. The device has a peak responsivity of 0.32 A/W at ~ 26 mum at 5 K. It is demonstrated that the dopant migration-induced interface dipole effect can be used to extend the zero response threshold frequency (f ₀) of n-type HEIWIP detectors.     

Experience in the health promotion of children in opisthorchiasis foci

The analysis covers 2555 appendectomies, performed on an emergency and scheduled surgery basis in the clinic of emergency surgery.--State University Hospital "Queen Giovanna", Sofia, over the period 1985-1997. Relaparotomy is necessitated in 28 cases (1.09 per cent) because of various postoperative complications. Data are presented on the number of relaparotomies, done under conditions of emergency and scheduled surgery, and with a special reference to the pathoanatomical character of appendicitis. The underlying causes of undertaking relaparotomy and postoperative lethality are analyzed. As shown by the obtained results post-relaparotomy mortality rate is the highest after primary operation for destructive form of appendicitis and advanced form of peritonitis.     

CO<Subscript>2</Subscript> gas sensitivity of sputtered zinc oxide thin films

For the first time, sputtered zinc oxide (ZnO) thin films have been used as a CO₂ gas sensor. Zinc oxide thin films have been synthesized using reactive d.c. sputtering method for gas sensor applications, in the deposition temperature range from 130–153°C at a chamber pressure of 8·5 mbar for 18 h. Argon and oxygen gases were used as sputtering and reactive gases, respectively. ZnO phase could be crystallized using a pure metal target of zinc. The structure of the films determined by means of X-ray diffraction method indicates that the zinc oxide single phase can be fabricated in this substrate temperature range. The sensitivity of the film synthesized at substrate temperature of 130°C is 2·17 in the presence of CO₂ gas at a measuring temperature of 100°C.