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Byline: Z. Janu, F. Soukup, R. Tichy Electronic transport studies are important tool to get information on the electronic system and quality of a material. Recent progress in experimental techniques leads to higher resolution data, providing insight in physical processes on much finer scale. Many intriguing, particularly quantum phenomena of electron transport in solids emerge when conduction electrons are 'cold', with field induced kinetic energy I[micro] < < I*BT. We focus on phase transitions accompanied by abrupt changes of electrical conductivity in a narrow temperature range. Examples are superconducting-normal, metal-insulator, martensitic or the Verwey-transition in Fe3O4. In many cases a shape and details in the transition are blurred with increasing current density. But the 'cold' conduction electrons may reveal details and offer high-resolution data for detailed analysis of elastic and inelastic electron scattering.

Due to its high tolerance to acid rain, the North American Colorado blue spruce ( Picea pungens) has been among the most frequent substitute tree species used in reforestation programmes in spruce mountain forests in the Ore and Sudeten Mountains in the Czech Republic after destruction by sulphur dioxide pollution in the second half of the last century. This species was planted on more than 8800 ha of destroyed mountain forest stands in the Ore Mountains alone. New plantations prospered until a massive outbreak of the gemmamyces bud blight, first identified in 2009. The causal agent, Gemmamyces piceae, induced massive bud blight in infected trees - bud loss progressively increased to 70-80% or more, and because the trees were not able to replace the natural loss of older needles, they quickly withered and died. Many plantations disrupted by the pathogen had to be cut down. Although several resistant genotypes have been identified, the cultivation of this species in forest stands has no future in this area. Because this disease was also identified in several ornamental plantations in the area, the bud blight epidemic haunts public green space administrators and nursery and Christmas tree plantation owners. Other pathogens and pests, such as Lophodermium piceae, Sirococcus conigenus and Elatobium abietinum, have also been identified as involved in the damage to P. pungens. [ABSTRACT FROM AUTHOR]

Methyl formate was used as the solvent of biodegradable oligoesters for the fabrication of microspheres with encapsulated bovine serum albumin (BSA). The procedure of dispersion of the double emulsion of the w/o/w type and its dilution and solvent extraction is very rapid, taking only several minutes. A higher yield and better encapsulation efficiency were obtained with copolymers of DL-lactic acid with mannitol than with pure linear poly DL-lactic acid. The procedure was accelerated, and yields and encapsulation efficacy were enhanced by the addition of 5% methyl formate to the external water phase. The microspheres were smaller than 100mum. No benefits were obtained from the addition of wetting agents or other additives to the intermediate (oligoesteric) phase. Further development should concentrate particularly on hydrodynamic conditions and optimization of the composition of the external phase. [ABSTRACT FROM AUTHOR]

We show a continuous reading superconducting quantum interference detector magnetometer used to measure the magnetic moment of small samples of materials as a function of an applied magnetic field, temperature, and time. A sample is held stationary while the magnetic field and sample temperature may be varied continuously in an arbitrary way, determined by the user. The applied field range is ±25 mT and the temperature range is 4.2-150 K. The advantage of a stationary sample technique is that the sample is not exposed to variations in the magnetic field or temperature, which may set in when the sample is moving. An evaluation of the measurements is not bound by the dipolar magnetic moment of the sample. High linearity of the detection system, low harmonic distortion of the applied time-varying magnetic field, and precise sample temperature control make this device suitable for studies of phase transitions, hysteretic phenomena, and nonlinear phenomena in magnetic materials and superconductors. The magnetometer's sensitivity (noise floor), i.e., magnetic moment noise spectral density, is 10 pA m 2 Hz -1/2 in the white noise region.

The authors submit a report on 225 patients operated by the percutaneous approach on the kidney during the period between March 1985 and February 1987. From 231 operations on account of lithiasis concrements were removed in 94.8%. No major complications were observed. The mean period which elapsed from operation to discharge was 8 days in one-stage operations and 19 days in multiple-stage operations. The authors discuss the indications and some technical conditions of the method.

The authors discuss the problem of the most suitable anaesthesia for percutaneous extraction of renal concrements. Based on 203 anaesthesias, they compare the combination of local anaesthesia with intravenous administration of ketamine with a tranquilizer, local anaesthesia with administration of phentanyl and a tranquillizer and local anesthesia with phentanyl and a analgetic-spasmolytic mixture. In the great majority of patients they prefer a combination of local anaesthesia and continuous administration of phentanyl and fractionated administration of an analgetic-spasmolytic mixture.

During transurethral electroresection in the posterolateral bladder neck, trigone and posterior urethra, unintentional contractions of the thigh-adductor muscles may occur due to irritation of the obturator nerve. The sudden displacement of the bladder wall against the cutting loop may cause a perforation of the bladder. The authors describe the topographic relation of the bladder wall to the passage of the obturator nerve in the minor pelvis. The technique of obturator nerve block by local anaesthesia is described and its efficacy is demonstrated in 21 patients.