Silviculture Methods in Polish Forests Affected by Industrial Pollutants

Data presented by the Headquarters of the State Forests in Poland indicate that about 645,000 ha were threatened by industrial emissions in the mid-1980s. The authors have carried out a complementary study and have come to the conclusion that about 2.8 million ha were threatened in 1988. Due to the future emissions the area under threat is estimated to increase to about 4.2 million ha in the year 2000. This rapid development of decline requires a changed silvicultural management. Guidelines for the changed management of the following order of stands threatened by air pollutants are discussed: (a) stands characterized as being "in the regeneration class"; (b) clear-cut stands; (c) second-order clear-cut stands; (d) seedlings and thickets; (e) stands of medium age classes; and (f) stands with a share of deciduous species exceeding 20%

CHARACTERISTICS OF KINEMATICS AND KINETICS OF STROKES IN KARATE -BIOMECHANICAl APPROACH

The purpose of the paper is to discuss the matter of results of stroke velocity measurements and kinetic parameters (maximum force of stroke and angle of impact) of hand strokes (gyaku tsuki) and leg strokes (mae geri, yoko geri) in karate shotokan. A group of competitors, consisting of 21 persons, took part in the laboratory experiment. Measurements of kinetic parameters were realised on Kistler three-component force plate with synchronous measurement of hand (foot) velocity which was executed on MRC selfconstructed equipment

THE ANALYSIS OF THE TAKE OFF DYNAMICS IN THE TRAINING EXERCISES OF HIGH JUMPERS

The purpose of this paper is to identify the time-force characteristics of the take-off dynamics in six standard training exercises of high jumpers, in order to define which conform best to the take-off characteristics of the high jump. The analysis of similarities of the characteristics was based on the flow of the ground reaction forces vertical component, which produced several parameters describing the dynamics of take-off. KISTLER force plate was used

LOADS ACTING ON THE LOCOMOTIVE SYSTEM OF PROFESSIONAL FEMALEVOLLEYBALL PLAYERS DURING THE LANDING PHASE OF SPIKES AND BLOCKS

The purpose of this study was to identify force and time characteristics of ground reaction forces produced during the landing phase of volleyball technical elements: blocks and spikes. Applying piezoelectric dynamometry and video recording, a series of tests were carried out with the participation of four female volleyball players of the first team of AZS AWF sports club competing in the Female Volleyball League. The recorded force vs time line graphs of ground reaction Rx(t), Ry(t) and Rz(t) were used to calculate the values of kinematic-dynamic parameters that describe the level of dynamic loads. Results show that the majority of loads in these movement tasks is significant and may be traumatogenic

DYNAMIC OVERLOADS IN SELECTED GYMNASTIC EXERCISES

The purpose of this study is to identify force and time characteristics of ground reaction forces produced in selected movement exercises of gymnastics that contain elements of take-off and landing. The study was conducted over four athletes, two of sports acrobatics (17 and 18 yo) and two of artistic gymnastics (10 and 11 yo). The vertical ground reaction forces recorded in time were used to calculate maximum force values and characteristic times, and permitted an evaluation of the degree of dynamic overloads. The results of the tests show high levels of dynamic overloads, which may have traumatogenic character

STRUCTURE OF MUSCLE STRENGTH AMONG PROFESSIONAL CLASSICAL FEMALE DANCERS

The work characterizes in detail the level of static torques in classical ballet female dancers, in comparison to their peers, students of physiotherapy at the University of Medical Sciences. The analysis of torques consisted in evaluation of 13 functional muscle groups (11 groups of left and right extremities and 2 of the trunk). Apart from few exceptions, the tested dancers were stronger, however the difference was not always statistically significant

IUPAC-NIST solubility data series. 81. Hydrocarbons with water and seawater-revised and updated. Part 5. C7 hydrocarbons with water and heavy water

The mutual solubility and related liquid-liquid equilibria of C7 hydrocarbons with water and heavy water are exhaustively and critically reviewed. Reports of experimental determination of solubility in 23 chemically distinct binary systems that appeared in the primary literature prior to end of 2002 are compiled. For 9 systems sufficient data are available to allow critical evaluation. All data are expressed as mass percent and mole fraction as well as the originally reported units. In addition to the standard evaluation criteria used throughout the Solubility Data Series, a new method based on the evaluation of the all experimental data for a given homologous series of aliphatic and aromatic hydrocarbons was used

IUPAC-NIST solubility data series. 81. Hydrocarbons with water and seawater - Revised and updated. Part 8. C9 hydrocarbons with water

The mutual solubility and related liquid-liquid equilibria of C9 hydrocarbons with water are exhaustively and critically reviewed. Reports of the experimental determination of solubility in 18 chemically distinct binary systems that appeared in the primary literature prior to the end of 2002 are compiled. For 8 systems, sufficient data are available to allow critical evaluation. All data are expressed as mass percent and mole fraction, as well as the originally reported units. In addition to the standard evaluation criteria used throughout the Solubility Date Series, a new method based on the evaluation of the all experimental data for a given homologous series of aliphatic and aromatic hydrocarbons was used