Volumen 72 (2020): Edición 3 (September 2020)

The safe transition from a higher pressure atmosphere to a lower pressure atmosphere is accomplished by planning the decompression process, typically through changes in pressure and/or composition of the breathing mix in a function of time. However, the decompression process is affected by a much greater number of inherent factors than changes in pressure and composition of the breathing mix. Their values should be kept within certain ranges, however, there are circumstances when it is not possible to maintain control over them. In this situation, they become elements of the residual risk of the decompression process. The safety of decompression should be ensured, inter alia, by analysing the residual risk for each execution of the decompression process.

Pre-dive checks and dive logs are fundamental documentation for any diving operation and must be incorporated as mandatory ‘good operating practices’ in scientific diving (SD) projects. Data included in dive logs may vary in detail, however, there is basic information to provide based on global standards. Differently to several developed countries in Europe, North America and Australasia, there are countries with incipient, sometimes non-regulated, SD programmes. In this article the importance of documentation in SD is highlighted and record forms are provided as templates, including versions both in English and Spanish. The Diving Supervisor (DS) is the designated person to fill the ‘Daily SciDive Log’ and ‘SCUBA & surface-supplied LogSheet’ (Table 1, 2 and 3, respectively), whilst every diver is responsible for filing their own ‘SciDiver’s Digital LogBook’ (Table 4). General and specific considerations for all tables are described throughout the text. This effort was done to facilitate systematic data management and start developing the bases towards solid national/regional standards on scientific diving operations, particularly for those countries with incipient (scientific) diving programmes.

Background: This study aimed to assess the accuracy of force production by the limbs and to identify the ability to differentiate this force during a progressively increasing value, in response to different types of extrinsic feedback.

Material and methods: The study involved nineteen healthy and physically active boys and girls aged 12.82±0.34 years, body height 157.05±9.02 cm, and body mass 44.89±7.89 kg. The tasks were to perform a series of right and left upper limb pulls and pushes with increasing force using the levers of the kinesthesiometer and a series of lower limb presses on the pedal of the kinesthesiometer. The tasks were completed in three feedback conditions: no feedback, sound feedback, verbal feedback, and the retention test was used. To assess the level of accuracy of force production, the novel index of force production accuracy (FPAIndex) was used.

Results: The outcomes expressing the value of FPAIndex on the point scale indicated that the highest level of kinesthetic differentiation was observed when no feedback was provided (1.17 points), and the lowest kinesthetic differentiation was recorded when verbal feedback was provided (3.33 points). However, they were devoid of statistical value. The repeated-measures analysis of variance ANOVA with the Tukey post-hoc test (HSD) indicated a significant lowest (p=0.0402) level of accuracy of FPA (x̄ 36.12±18.29 [N]) only for the act of left lower limb press (LL PRESS) in the retention test, while no feedback was provided to the subjects.

Conclusions: The results of this study showed that verbal and sound extrinsic feedback did not affect the accuracy of force production by the upper and lower limbs and the ability to differentiate this force in simple movements among children.

The article presents the results of research on the application of a physical exercise programme to improve the underwater orientation of military divers. The research was carried out on a group of 120 soldiers, some of whom (the study group) underwent additional training for 3 months. During the underwater straight-line swimming test in poor visibility conditions, the test group achieved statistically significantly better results than the control group. The test consisted in measuring the angle of deviation of the diver’s route from the given straight line.

Mercury (Hg) is recognised as a global environmental pollutant. Despite numerous studies being conducted around the world, the transformation of mercury in natural environments is still not fully understood. In addition, increasing droughts and heavy rains are currently observed to contribute to changes in the circulation of Hg. The purpose of this study was to recognise the influence of extreme meteorological and hydrological conditions on the inflow of various forms of mercury to the coastal zone of the Bay of Puck. The studies were carried out at estuarial stations of four rivers belonging to the southern Baltic Sea catchment: Reda, Zagorska Struga, Gizdepka and Płutnica. The results showed that meteorological and hydrological parameters affect mercury speciation in river catchments, which translates into inflow of labile mercury to the southern Baltic Sea.

The study presents the characteristics of drinking water sources and subsequently performs an analysis of the deviations from the norm in terms of ions of iron, manganese, ammonia, sodium, chlorides as well as other factors affecting the quality of drinking water in the years 2015 - 2017 occurring in individual water intake points in the Kutno district.