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1

Detecting food limitation of bacterial growth during dilution experiments

Rychert Krzysztof

Oceanologia

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2022

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No. 64 (3)

405--416

EN

The dilution method is typically applied to estimate the growth and mortality rates of phytoplankton, but it is also used to study bacterioplankton. The method comprises creating a gradient of dilutions to reduce the encounter rates between bacterivores and bacteria, thus allowing for estimations of bacterial growth and grazing pressure exerted on the bacteria. However, the manipulations involved in the method can lead to biased results. In this study, 12 dilution experiments performed in the coastal zone of the Baltic Sea were accompanied by additional measurements capable of detecting possible artefacts. Only six measurements performed during spring and summer (March–August) produced results that were free of artefacts and were statistically significant. During fall and winter (October–February) measurements were unsuccessful because of food limitation of bacterial growth during experimental incubation. Twice (in September and October) bacterial growth and grazing mortality rates were underestimated because grazing pressure was not successfully removed. The study demonstrated that 24-hour and five-day oxygen consumption measurements incorporated into dilution experiments permitted estimating the fraction of biodegradable organic matter used during incubation, and, thus, detecting the food limitation of bacterial growth.

2

Can strength exercise affect the muscle oxygen saturation response?

Miranda-Fuentes Claudia, Chirosa-Rios Luis, Guisado-Requena Isabel, García-Pinillos Felipe, Del-Cuerpo Indya, López-Fuenzalida Antonio, Ibacache-Saavedra Paulina, Jerez-Mayorga Daniel

Acta of Bioengineering and Biomechanics

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2022

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Vol. 24, no. 2

37--45

EN

The objective of the study was to describe and compare the acute response of muscle oxygen saturation (SmO2) and hemoglobin concentration (Hgb) in the vastus lateralis (VL) during resistance exercise protocols until failure. Methods: Sixteen males were considered (mean ± SD, age = 36.12 ± 6.40 years). Two familiarization sessions and one evaluation session were carried out where three force protocols were executed in the VL, one of them was isometric load (P1) and two of dynamic load (P2 and P3). SmO2 [%] and Hgb [g/dL] were measured before and after each of these protocols. For P1, three series of 8 s of maximum isometric strength with the rest of 60 s between each set, the average isometric strength (AIS), and the isometric peak strength (IPS) were also recorded. After five minutes, P2 was performed, with an initial load of 40% of AIS. Then, at 30 minutes, P3 was performed considering an initial load of 40% of IPS. Results: The results suggest (I) minimum levels of SmO2 (66.31 ± 9.38%) and Hgb (12.22 ± 0.55 g/dL) during P2, (II) no significant differences were observed between the average loads of the respective protocols for SmO2 and (III) muscle Hgb differed significantly between rest with P1 and P3. Conclusions: Exercises of increasing intensity and of short duration do not significantly modify SmO2. However, Hgb increases substantially compared baseline values.

3

Energy expenditure and physiological responses during walking on a treadmill and moving on the Torqway vehicle

Maciejczyk M., Wiecek M., Szymura J., Szygula Z.

Acta of Bioengineering and Biomechanics

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2016

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Vol. 18, no. 2

137--143

EN

Purpose: One of the new products which can be used to increase physical activity and energy expenditure is the Torqway vehicle, powered by the upper limbs. The aim of this study was to (1) assess the usefulness and repeatability of the Torqway vehicle for physical exercise, (2) compare energy expenditure and physiological responses during walking on a treadmill and during physical effort while moving on the Torqway at a constant speed. Methods: The participants (11 men, aged 20.2 ± 1.3) performed the incremental test and submaximal exercises (walking on the treadmill and moving on the Torqway vehicle at the same speed). Results: Energy expenditure during the exercise on the Torqway was significantly higher (p = 0.001) than during the walking performed at the same speed. The intensity of the exercise performed on the Torqway expressed as %VO2max and %HRmax was significantly ( p < 0.001) higher than during walking (respectively: 35.0 ± 6.0 vs. 29.4 ± 7.4 %VO2max and 65.1 ± 7.3 vs. 47.2 ± 7.4 %HRmax). Conclusions: Exercise on the Torqway vehicle allows for the intensification of the exercise at a low movement speed, comparable to walking. Moving on the Torqway vehicle could be an effective alternative activity for physical fitness and exercise rehabilitation programs.

4

Obuwie - ważny element ubioru człowieka

Serweta W., Olejniczak Z.

Przegląd Włókienniczy - Włókno, Odzież, Skóra

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2015

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nr 11

19--24

EN

Footwear is an important element of an attirement, which protects the human foot from injuries and negative effects of extraneous environmental conditions. Moreover shoes are necessary component of locomotor apparatus, cause human sole is not adapted to long - distances walking without protection. Modern shoe is equipped with stiffened midsole, hightened heel or arch supports, which has been changed the foot strike. Today a typically strike of human gait is rearfoot - which the point of the first contact the ground is heel. The specific rigid construction of shoes follows that natural barefoot strike has been changed on rearfoot. On the other side, set of materials which is used for shoe production like leather, woven or unwoven textiles or synthetics materials are an important factor to influence the quality of footwear and affects the comfort of use. Therefore innovative textiles and polymer materials are desirable to create new protective and functional properties of shoes.

5

Koszt fizjologiczny pracy strażaka w ubraniu specjalnym

Węsierski T., Kowalczyk P.

Bezpieczeństwo i Technika Pożarnicza

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2015

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Nr 2

63--72

PL

Cel: Celem artykułu jest określenie wpływu ubrania specjalnego na obciążenie strażaka w trakcie prowadzenia działań ratowniczych. Projekt i metody: W artykule przedstawiono wyniki badań wykonanych za pomocą ergospirometru Start 2000M. Badaniu poddano ratownika w wieku średnim, o przeciętnej budowie ciała (179 cm, 92 kg, 36 lat), powtarzając pomiar pięciokrotnie. Każde badanie było wykonane na czczo, w różnych dniach, w pomieszczeniu zamkniętym o stabilnych warunkach temperaturowych oraz wilgotności (21–22°C, wilgotność względna 33–41%). Użyte w badaniach czterowarstwowe strażackie ubranie specjalne spełniało wymagania normy PN-EN 469:2008. Masa ubrania w przeliczeniu na jednostkę powierzchni wynosiła 620 g/m2. Wyniki zostały odniesione do warunków pracy w stroju sportowym, które uznano za niepowodujące obciążenia termicznego i dające możliwie najwyższy komfort. Badania porównawcze wykonano w trakcie obciążenia pracą polegającą na stałym 10-minutowym szybkim marszu (v = 7 km/h) poprzedzonym czterominutowym okresem spoczynkowym. W toku badań rejestracji i analizie poddano takie parametry jak częstość skurczów serca (HR), wentylacja minutowa płuc (VE), zużycie tlenu na kilogram masy ciała (VMO2), częstość oddechu (BF). Wyniki: Wszystkie badane parametry wskazały wzrost obciążenia pracą w ubraniu specjalnym w odniesieniu do ubrania sportowego. Ponadto wszystkie zakresy analityczne poza częstością oddechową podczas pracy w obciążeniu dla ubrania specjalnego (VBF = 21,7%) charakteryzowały się współczynnikiem zmienności poniżej 20%, a zatem oznaczały niskie zróżnicowanie cechy. Potwierdzają to również niskie wartości niepewności pomiarowych, które poza BF są niższe od 5%. Żaden z przedziałów ufności dla α = 0,1 nie zazębiał się, a kryterium porównawcze w każdym z przypadków spełniało zależność |X2 – X1| > ΔX1 + ΔX2. Zatem wartości parametrów w ubraniu specjalnym można uznać za istotnie wyższe od parametrów w stroju sportowym z prawdopodobieństwem równym 90%. Wnioski: Różnica parametrów mierzonych pomiędzy strojem sportowym a ubraniem specjalnym jest duża i wynosiła co najmniej 16,7% (VM02), osiągając w przypadku BF aż 51%. Jako pomiar analizowany przyjęto pomiar będący medianą badanej serii pomiarowej odpowiednio dla ubrania specjalnego oraz stroju sportowego. Tak znaczne różnice wskazują konieczność podjęcia kroków mających na celu skonstruowanie ubrań specjalnych powodujących mniejsze obciążenie organizmu. Dane literaturowe wskazują, iż sam aspekt psychologiczny prowadzenia działań (np. przystąpienie do ataku na pożar) powoduje wzrost HR do 71% osobniczego HRmax oraz VE do ~56 dm3/min, co pokazuje konieczność ograniczenia innych czynników stresu – jednym z nich może być zbyt niski komfort pracy w ubraniu specjalnym.

EN

Aim: The purpose of this article is to determine the demands placed on a firefighter as a result of wearing special garments during rescue operations. Design and Methods: The article presents results from research performed with the aid of ergo-spirometer Start 2000M. A middle aged firefighter, of average physical build (36 years of age, 179 cm high, 92 kg weight) was exposed to research tests which were repeated five times. Each test was performed after fasting, on different days in an enclosed space with stable temperature conditions and humidity (temperature in the range 21–22°C and relative humidity 33–34%). The mass of the garment was calculated at 620 g/m2. Results were compared with performance where sport attire was worn. It was assumed that wearing sportswear precluded generation of heat and probably afforded maximum comfort. Comparative tests were performed for constant workload sessions consisting of a 10-minute quick march (v = 7 km/h), preceded by a four minute rest period. During the course of research, parameters such as the heart rate (HR), lung ventilation per minute (VE), oxygen consumption for every kilogram of body weight (VMO2) and breathing rate (BF) were recorded and analyzed. Results: All tested parameters revealed a higher workload during tests, when the special garment was worn compared with sportswear. Additionally, all analysed parameters whilst attired in the special garment, apart from breathing frequency (VBF = 21.7%) were characterized by a variation coefficient of less than 20% (low population differential). This is confirmed by low uncertainty values, which are, apart from BF, lower than 5%. None of the confidence intervals for α = 0.1 overlapped, and the comparative criterion for each of the cases fulfilled the dependence |X2– X1| > ΔX1 + ΔX2. Thus, parameter values for a special garment are significantly higher than parameters for sportswear with a probability of 90%. Conclusions: The difference between measured parameters for sportswear and specialist garment is large, at least 16.7% (VMO2) and in the case of BF rising to 51%. The median of all measurements obtained during experiments, for conditions involving specialist attire and sportswear, was exposed to analysis. Such significant differences indicate a need for steps to manufacture special garments, which cause less stress on the body. Data contained in literature reveals that the psychological aspect alone, of performing operational activities (eg. initial approach to attack the fire) causes an increase in HR to 71% of an individual’s maximum heart rate and VE up to ~56 dm3/min. This indicates a need to minimise the influence of other stress factors, one of which may be relatively low comfort at work whilst wearing a special garment.

6

Parametr AT4 jako wskaźnik stopnia stabilizacji odpadów po mechaniczno-biologicznym przetworzeniu

Kilian E., Macedowska-Capiga A.

Prace Instytutu Ceramiki i Materiałów Budowlanych

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2011

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R. 4, nr 8

88-94

PL

Wytyczne dotyczące wymagań odnośnie do procesów kompostowania, fermentacji i mechaniczno-biologicznego przetwarzania odpadów, opracowane przez Departament Gospodarki Odpadami Ministerstwa Środowiska, mówią o konieczności wdrożenia pomiaru parametru AT4 jako uzupełnienia oceny stopnia ustabilizowania odpadów, obok wartości straty prażenia i TOC. W artykule zawarto charakterystykę procesu mechaniczno-biologicznego przetwarzania odpadów oraz opisano wskaźnik aktywności oddechowej AT4 i metody jego określania.

EN

The guidelines on requirements for the processes of composting, fermentation and mechanical-biological treatment of waste issued by Department of Waste Management in the Ministry of the Environment suggest the necessity to implement the measurement of parameter AT4 as an additional means for evaluation of waste stabilization degree in addition to L.O.I and TOC. This work includes characteristics of the mechanical-biological treatment of wastes and the description of the 4-days respiration activity AT4 and methods of its determination.

7

Szybkość wnikania i konsumpcji tlenu w kolumnowych reaktorach barbotażowych z zawiesiną drożdży

Kawalec-Pietrenko B., Konopacka-Łyskawa D., Łazarczyk M.

Inżynieria i Aparatura Chemiczna

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2006

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Nr 6s

114-115

EN

An influence of the air flow rate and concentration of active and inactivated Saccharomyces cerevisiae yeasts on the oxygen transfer rate in the bubble column and the external loop airlift reactor is presented.

8

Effect of deltamethrin on mortality and oxygen consumption in Porcellio scaber Latr (Isopoda

Unkiewicz-Winiarczyk A., Gromysz-Kałkowska K., Szubartowska E.

Chemia i Inżynieria Ekologiczna

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2005

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Vol. 12, nr 10

1147-1153

EN

Adult individuals of both sexes of Porcellio scaber Latr. were poisoned with deltamethrin in the form of acetone solution (together 297 (female)) and 291(male) ] or were kept on litter contaminated with water-based solutions (together 260 (female)) and 250 (male)). LD50 values demonstrated high sensitivity of P. scaber to deltamethrin, males turned out to be more sensitive than females. The highest oxygen use noted immediately after poisoning with deltamethrin pipetted on the body covering is connected with a stale of excitation of the nervous system of tested isopods and their higher motor activity. Males kept on contaminated litter displayed lowered oxygen use during the first week of experiment because deltamethrin decreased feeding activity. This pyrethroid present in the litter may be considered antifeedant by the animals and food coated by them may be taken as inedible.

PL

Dorosłe osobniki Porcellio scaber intoksykowano deltametryną w postaci acetonowych roztworów (łącznie 297 (płeć żeńska) i 291 (płeć męska)) bądź przetrzymywano na skażonej wodnymi roztworami deltametryny ściółce (łącznie 260(płeć żeńska) i 250 (płec męska). Małe wartości LD50 wskazują na dużą wrażliwość skorupiaków na ten piretroid. Samce były bardziej wrażliwe aniżeli samice. Największe zużycie tlenu u skorupiaków, notowane bezpośrednio po naskórkowym zatruciu piretroidem, związane jest ze stanem nadwzbudzenia układu nerwowego zwierząt oraz ich większą aktywnością lokomotoryczną. U samców przetrzymywanych na skażonej ściółce odnotowano spadek zużycia tlenu w ciągu pierwszego tygodnia doświadczenia. Związany jest on ze zmniejszoną aktywnością pokarmową zwierząt, gdyż deltametryna może mieć charakter antyfidantu.

9

The influence of ventilatory support on coronary flow and oxygen consumption in different circulatory conditions

De Lazzari C., Darowski M., Ferrari G., Mimmo R., Guaragno M., Tosti G.

Biocybernetics and Biomedical Engineering

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2003

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Vol. 23, no. 1

103-110

EN

The aim of this work is to predict the influence of mechanical ventilation on cardiac output, coronary flow and left ventricular myocardial oxygen consumption in different circulatory conditions. To study this interaction we used a computer simulator of human cardiovascular system in which lumped parameters models were used to reproduce the circulatory phenomena in terms of pressure and volume relationships. Variable elastance models reproduce the Starling's law of the heart, for each ventricle. In the study the left ventricular elastance assumed two different values. Symetric arterial resistance was changed during the simulation. The influenece of mechanical ventilation was introduced by positive mean thoracic pressure. Positive thoracic pressure, changes of peripheral resistance and different ventricular elastance values have a significant influence on cardiac output, coronary flow and myocardial oxygen consumption.

10

Seasonal changes of itersititial community respiration in a Baltic sandy beach

Urban-Malinga B., Opaliński K. W.

Oceanological Studies

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2002

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Vol. 31, No. 3-4

57-70

EN

Interstitial community respiration in a Baltic sandy beach on the Gulf of Gdańsk was investigated in terms of sediment oxygen consumption over a seasonal cycle. The study was carried out at four locations on the beach slope (littoral, waterline, splashzone and middle beach). Oxygen uptake changes over time were not statistically significant and no correlation was found between sediment respiration and water temperature. It seems that food supply to the sandy beach system is the predominant factor determining the interstitial community metabolism. The lowest values of oxygen consumption (9-33 cm3 O2 m-2 h-1) were noted in the middle beach station; the highest results (up to 212 cm3 O2 m-2 h-1) were related to the littoral site. Organic matter concentration in the sediment ranged between 0.09 and 0.9% dwt.

11

Vertical zonation of the total, biotic and abiotic oxygen consumption on a Baltic sandy beach

Urban-Malinga B., Opaliński K. W.

Oceanological Studies

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1999

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Vol. 28, No. 3-4

85-96

EN

The oxygen consumption of a sandy beach on the Gulf of Gdansk (southern Baltic Sea) was determined. The study was carried out in three sediment layers (0-1, 1-6, 6-11cm) at four localities on the beach profile. Total oxygen consumption lay between 0.59 and 4.33 mm3 O2 cm-3 h-1. A significant linear correlation was found between sediment depth and total oxygen consumption in the littoral zone (r = 0.85) and in the splash zone (r = -0.71). The highest biotic oxidation was recorded in the upper sediment layers in the splash zone (0-1 cm: 1.57 mm3 O2 cm-3 h-1) and at the waterline (1-6 cm: 1.87 mm3 O2 cm-3 h-1). Meiofaunal respiration constituted 0.1- 3.0% of the biotic oxygen consumption. Abiotic oxygen consumption ranged between 0.07 and 3.43 mm3 O2 cm-3 h-1 and was the dominant component of total oxidation in deeper layers.