W. E. KRUMBEIN (Editor), Environmental Biogeochemistry and Geomicrobiology. Vol. 1: The Aquatic Environment. XVII + 394 Seiten, 94 Abb., 70 Tab. Vol. 2: The Terrestrial Environment. XVII + 315 Seiten, 76 Abb., 68 Tab. Vol. 3: Methods, Metals, and Assessment. XVII + 339 Seiten. 96 Abb., 52 Tab. Ann Arbor 1978. Science Publishers Inc. $ 32.50

1979 ◽  
Vol 19 (8) ◽  
pp. 594-594
Author(s):  
W. Schwartz
2021 ◽  
Vol 11 (9) ◽  
pp. 3739
Author(s):  
Xing Chi ◽  
Qiang Zhan

Mobile robots that can survive in unstructured wildernesses is essential in many applications such as environment detecting and security surveillance. In many of these applications, it is highly desirable that the robot can adapt robustly to both terrestrial environment and aquatic environment, and translocate swiftly between various environments. A novel concept of amphibious spherical robot with fins is proposed in this paper, capable of both terrestrial locomotion and aquatic locomotion. Unlike the traditional amphibious robots, whose motions are commonly induced by propellers, legs or snake-like tandem joints, the proposed amphibious spherical robot utilizes the rolling motion of a spherical shell as the principal locomotion mode in the aquatic environment. Moreover, spinning motion of the spherical shell is used to steer the spherical robot efficiently and agilely; several fins are attached to the outer spherical shell as an assistance to the rolling motion. These two motion modes, rolling and spinning, can be used unchangeably in the terrestrial environment, leading to a compact and highly adaptive design of the robot. The work introduced in this paper brings in an innovative solution for the design of an amphibious robot.


2020 ◽  
Vol 2 (7A) ◽  
Author(s):  
Amelia Odell ◽  
Paul Eady ◽  
Ronald Dixon

Phenotypic and genotypic identification methods have been used to determine the temporal and spatial dynamics of AMR-Escherichia coli in a mainly rural watercourse that receives WWTP-effluent compared to a parallel river which does not. We aimed to investigate the incidence of plasmid-mediated mcr-1and β-lactamase-genes in E. coli recovered from both water and Asellus aquaticus samples throughout two-calendar-years. Samples of the water and A. aquaticus were recovered from the relevant locations each month. CHROMagar ESBL agar was used throughout to isolate and identify ESBL-E. coli. The presence of AMR-genes was confirmed using the ‘BSAC’ antibiotic-disk-synergy method and PCR analysis to confirm the presence of mcr-1and ESBL-genes. The CHROMagar ESBL agar was found to be 99.7% (n=578) accurate when confirmed with a PCR analysis of the ESBL-genes. Seventy-six-point-six percent (n=449) of the isolated ESBL-E. coli were correctly identified as ESBL-producing organisms using the ‘BSAC’ method. Interestingly 61.9% (n=358) of the ESBL-E. coli were also found to carry the mcr-1 gene. Our data shows that AMR levels were highest at the WWTP-effluent throughout the two-years for both water and A. aquaticus samples. The incidence of AMR-E. coli 1km downstream of the effluent discharge was equivalent to the parallel river sites, suggesting that the dispersal of AMR from the WWTP-effluent is limited, although AMR-E. coli were found in relatively high numbers at the WWTP-effluent. We argue that the presence of AMR in the freshwater invertebrate A. aquaticus could represent an important route by which AMR can spread from the aquatic environment to the terrestrial environment.


2021 ◽  
Vol 12 (Vol.12, no.1) ◽  
pp. 27-30
Author(s):  
Iustina CONDURACHE ◽  
Marius TURNEA ◽  
Mariana ROTARIU

Introduction. Exercise programs in the aquatic environment have as their main objective the improvement and maintenance of physical capacity/ capability, these being in continuous development and diversification. Water exercise amplifies the effects of general physical exercise, by allowing a more precise control over the movement of each body segment and of the body as a whole. The aquatic environment offers a number of beneficial effects compared to ones offered by the terrestrial environment. The benefits obtained through the aquatic activities are fundamental and are reflected throughout the entire body including both motor, functional and aesthetic level. Material and method. The objective of this study is represented by the identification of new forms of physical exercise that will increase the effort’s capacity. In order to achieve this goal, several methodological requirements were met, such as: successive engagement of the joints and muscle groups in effort (starting with the neck’s muscles, shoulders, arms, torso and legs, simultaneously with scapular-humeral joints, spine and coxo-femoral joints and legs), the gradually usage of exercises, starting with the most basic and then increasing the complexity of the exercises, the usage of the accessible exercises in the beginning of the training, executed with high amplitude and reduced speed, focusing on the correctness of the execution, the selection and the adequate/ appropriately usage of the initial positions according to the subject’s particularities and the shape/form of the exercise, the optimal control of the effort, achieved through a number of iterations, optimal execution time and breaks, the sets of general physical exercises will consist of sets of 8-12 exercises/reps, the principle of symmetry in the execution of the exercises has to be respected, the continuity of practicing a set of exercises for 6 to 8 consecutive lessons, the recommended work method is fragmented-imitative, efficiently combining the explication with the demonstration, the number of repetitions and the movement’s correction. Results and discussions. Analyzing results obtained after the evaluation, we have noticed significant growth in the functional and motor capacities. Conclusions. The systematization of water activities on objective criteria effectively contributes to their knowledge, while allowing them to be included in the spectrum of recreational, sporting, relaxing or therapeutic activities. Keywords: acvatic activities, physical exercise, evaluations,


2021 ◽  
pp. 314-317
Author(s):  
Iustina CONDURECHE ◽  
Luminița CONFEDERAT ◽  
Mariana ROTARIU ◽  
Marius TURNEA

Introduction. Exercise programs in the aquatic environment have as their main objective the improvement and maintenance of physical capacity/ capability, these being in continuous development and diversification. Water exercise amplifies the effects of general physical exercise, by allowing a more precise control over the movement of each body segment and of the body as a whole. The aquatic environment offers a number of beneficial effects compared to ones offered by the terrestrial environment. The benefits obtained through the aquatic activities are fundamental and are reflected throughout the entire body including both motor, functional and aesthetic level. Material and method. The objective of this study is represented by the identification of new forms of physical exercise that will increase the motor’s capacity. In order to achieve this goal, several methodological requirements were met, such as: successive engagement of the joints and muscle groups in effort (starting with the neck’s muscles, shoulders, arms, torso and legs, simultaneously with scapular-humeral joints, spine and coxo-femoral joints and legs), the gradually usage of exercises, starting with the most basic and then increasing the complexity of the exercises, the usage of the accessible exercises in the beginning of the training, executed with high amplitude and reduced speed, focusing on the correctness of the execution, the selection and the adequate/ appropriately usage of the initial positions according to the subject’s particularities and the shape/form of the exercise, the optimal control of the effort, achieved through a number of iterations, optimal execution time and breaks, the sets of general physical exercises will consist of sets of 8-12 exercises/reps, the principle of symmetry in the execution of the exercises has to be respected, the continuity of practicing a set of exercises for 6 to 8 consecutive lessons, the recommended work method is fragmented-imitative, efficiently combining the explication with the demonstration, the number of repetitions and the movement’s correction. Results and discussions. Analyzing results obtained after the evaluation, we have noticed significant growth in the functional and motor capacities. Conclusions. The systematization of water activities on objective criteria effectively contributes to their knowledge, while allowing them to be included in the spectrum of recreational, sporting, relaxing or therapeutic activities. Keywords: acvatic activities, physical exercise, evaluations,


2014 ◽  
Vol 5 ◽  
pp. 2424-2439 ◽  
Author(s):  
Petra Ditsche ◽  
Adam P Summers

Animal attachment to a substrate is very different in terrestrial and aquatic environments. We discuss variations in both the forces acting to detach animals and forces of attachment. While in a terrestrial environment gravity is commonly understood as the most important detachment force, under submerged conditions gravity is nearly balanced out by buoyancy and therefore matters little. In contrast, flow forces such as drag and lift are of higher importance in an aquatic environment. Depending on the flow conditions, flow forces can reach much higher values than gravity and vary in magnitude and direction. For many of the attachment mechanisms (adhesion including glue, friction, suction and mechanical principles such as hook, lock, clamp and spacer) significant differences have to be considered under water. For example, the main principles of dry adhesion, van der Waals forces and chemical bonding, which make a gecko stick to the ceiling, are weak under submerged conditions. Capillary forces are very important for wet adhesion, e.g., in terrestrial beetles or flies, but usually do not occur under water. Viscous forces are likely an important contributor to adhesion under water in some mobile animals such as torrent frogs and mayflies, but there are still many open questions to be answered. Glue is the dominant attachment mechanism of sessile aquatic animals and the aquatic realm presents many challenges to this mode of attachment. Viscous forces and the lack of surface tension under submerged conditions also affect frictional interactions in the aquatic environment. Moreover, the limitation of suction to the pressure difference at vacuum conditions can be ameliorated under water, due to the increasing pressure with water depth.


PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5572 ◽  
Author(s):  
Rebecca Jehne Hall ◽  
Simon K.A. Robson ◽  
Ellen Ariel

Background Several anatomical studies provide evidence that green turtles (Chelonia mydas) possess the necessary anatomy for colour vision. Behavioural experiments have previously been conducted with newly emerged hatchlings, concluding that they are attracted to shorter wavelengths compared to longer wavelengths within a terrestrial environment, suggesting a possible attraction towards blue. This paper assessed the colour vision of hatchlings within an aquatic environment, and investigated whether the attraction for shorter wavelengths remains consistent within water, whether the colour saturation of the chromatic stimuli was an important factor, and whether rearing and testing individual animals in different coloured housing tanks has an impact on their visual choices. Methods Forty-one hatchling green turtles were presented with a three-choice experiment where food was attached to three different coloured plates. The plates (blue, yellow, and red) were randomly arranged in the turtle’s tank and four different colour saturations were tested (100, 75, 50, and 25%). Turtles were individually placed into their housing tanks (coloured either red, white, blue or grey) with three different colour plates in front of them, from the same saturation level. The colour of the plate with food first approached and bitten by the turtle was recorded. Results The colour of the tank in which an individual was reared, and where experiments were conducted, significantly influenced which food item was selected on the different coloured plates. While individual turtles preferred to select the food items associated with blue plates across the entire experiment (66.1% of the time compared to 18.2% and 15.7% for yellow and red plates respectively), the preference for blue plates was influenced by the colour of the rearing/experimental tank. Individuals raised in red, white or blue tanks appeared to consistently prefer food on blue plates, but there appeared to be no plate colour preference by turtles in grey tanks. There was no significant effect of either colour saturation or the spatial arrangement of the three colours within an experimental tank on colour choice, and no significant interaction between tank colour and colour saturation. Discussion Thesefindings confirm that the terrestrial preference towards shorter wavelength colours, such as blue, compared to longer wavelength colours remains consistent within an aquatic environment. This preference for blue continues even as the colour saturation reduces from 100% down to 25%, and the colours become darker. Thus, it is suggested that green turtle hatchlings have a strong attraction towards blue. This attraction, however, is influenced by the colour of the tank the turtles were raised in. While this supports the notion that environmental colour may influence individual turtle visual capabilities, it suggests that this relationship is more complicated, and requires further investigation.


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