The threat of native molluscs by the New Zealand mud – snail (Potamopyrgus antipodarum (gray) = Угроза для местных моллюсков со стороны новозеландского слизня

Potamopyrgus antipodarum has been introduced to brackish and fresh waters of Europe probably in the first half of XIXth century, when the regular clipper lines have connected from 1840 the British Isles with New Zealand. Because these snails can survive in water to 24.6% salinity only, the transportation of individuals on outer parts of ship is impossible (Strzelec, 1996)

White Spots on Smoke Rings by Bruce Nauman: A Case Study On Contemporary Art Conservation Using Microanalytical Techniques

The artwork “Smoke Rings: Two Concentric Tunnels, Non-Communicating” by Bruce Nauman represents a case study of corrosion of a black patina-coated Al-alloy contemporary artwork. The main concern over this artwork was the widespread presence of white spots on its surface. Alloy substrate, patina, and white spots were characterized by means of energy-dispersive X-ray fluorescence and scanning electron microscopy with energy-dispersive spectroscopy. Alloy substrate was identified as an aluminum alloy 6,000 series Al–Si–Mg. Patina’s identified composition confirmed the documentation provided by the atelier. Concerning the white spots, zircon particles were found on patina surface as external elements

Stuff I Like

The written portion of the thesis will explain the process of the production. The first chapter will follow the show from conception to realization. It will include how and why the particular shows, scenes, songs, and actors were chosen. Chapter Two will illustrate the research done for the production. Chapter Three will be my personal rehearsal journal. Script analysis and script notes will comprise Chapter Four. This will include side notes that were written during the rehearsal process. Chapter Five will be a brief self-evaluation

Shell biometrical variability of Planorbis planorbis (Linnaeus, 1758) (Gastropoda, Pulmonata) in man-made water bodies of the Upper Silesian Industrial Region

The author has studied the effect of some environmental factors on the biometrical variability of the shell of the freshwater pulmonate snail Planorbis planorbis from several man-made water bodies of three types in the Upper Silesian Industrial Region. Out of the studied factors the calcium content in water did not seem to have a strong effect on the shell of the mollusc. On the contrary, a high content of magnesium ions in water seemed to inhibit the growth of the shell

The influence of industrial environment on the distribution of freshwater snails in Uppersilesian industrial region

The gastropod fauna of man-made reservoirs of the Upper Silesian Coal Basin (4 sinkhole ponds, 7 sand pits, 4 storage reservoirs) was studied. The author found the occurrence of 19 species. The most important environmental disturbances of the sinkhole ponds effected in the qualitative impoverishment of their gastropod fauna (10 species found), whereas the fauna of the sand pits and storage reservoirs, due to their more favourable water chemistry and physical conditions, was richer (15 and 17 species respectively). In all the types of reservoirs only certain species were observed to occur in mass. The analysis of influence of some environmental factors has shown that the total water hardness and the contents of calcium, iron, sulphates, chlorides, ammonia nitrogen, as well as age, size, and kind of bottom of the reservoirs do not affect the diversity of their malacofauna, what differs industrial reservoirs from natural ones. Excess of Mg++ ions in water seems a considerably limiting factor for most of the gastropod species found, this being especially distinct in sinkhole ponds

Study of the Role of Pressure Relaxation in Inviscid, Incompressible Flows

This thesis has investigated the role of pressure relaxation in inviscid, incompressible flows. A modified form of the classical Bernoulli equation was developed from a vector form of the Navier-Stokes equation which includes pressure relaxation and bulk viscosity. This modified Bernoulli equation was utilized to compare two-dimensional potential flow pressure distributions over a sphere, cylinder, backward and forward facing steps. Finally, the modified Bernoulli equation was utilized to compare the theoretical bounding free streamline to an experimentally observed free streamline over a knife edge. Results of these comparisons show that the classical form of the Bernoulli equation can over-predict the pressure when the steady-state velocity vector following a streamline is subject to significant curvature-based accelerations

Where hope blooms: appreciative inquiry case study into educational practices of feminist organizations

This thesis presents a qualitative case study of eight women associated with seven Canadian feminist organizations and their educational practices. The study employed the Appreciative Inquiry approach (Cooperrider & Srivastva, 1987) and case study methodology to recognize the value of feminist organizations’ work and illuminate their practices in the context of the sector’s precarious funding and scarcity of resources (English, 2016; English & Irving, 2015). The aim of the study was to understand how feminist organizations develop and deliver their educational programming balancing the tension, pointed out in the literature, between feminist ideals and organizational challenges like fundraising and professionalization (Bracken, 2011; D’enbeau & Buzzanell, 2013). The research question was situated against the background of experiential and transformative learning theories, feminist theory, feminist pedagogy, and acceptance that feminist organizations are places where vital adult education happens (Stromquist, 2019). A feminist framework lent itself best for the analysis of data in this study since it was conducted with women representing women’s organizations. A non-probabilistic, purposeful sampling and a criterion-based selection (Merriam & Tisdell, 2015) was used to identify and recruit research participants. Further, semi-structured interviews and document analysis served as data collection tools. The research produced three main findings titled Feminist Workplaces, Feminist Pedagogy, and Tensions. The study showed the selected feminist organizations to be inclusive and supportive workplaces, taking different approaches to balance the precarity of funding and service provision; their educational practices proved to be firmly grounded in feminist pedagogies

Occurrence and morphological variability of Gyraulus crista (Gastropoda: Pulmonata: Planorbidae) on different types of substratum in woodland ponds

Gyraulus crista is often a dominant component of lentic freshwater snail communities because it may occur in densities of hundreds of individuals/m2 across continents and in lentic water types. A study on the occurrence and conchological variability of the shell of G. crista was carried out on five different types of substrates in the anthropogenic woodland ponds at thirteen study sites. In order to answer the question of whether the existence of this species in different forms is affected by the quality of the inhabited substrates, various physico-chemical properties of the water, different bottom sediments and water level fluctuations, we examined the variation of forms across 5990 specimens of G. crista in woodland ponds. This research, which was supported by Redundancy Analysis (RDA), showed a highly significant association of G. c. spinulosus with leaf deposits and G. c. cristatus for T. latifolia remains. G. crista nautileus was mainly associated with T. latifolia and also with G. aquatica remains. They also showed no statistically significant relationship between the occurrence of particular conchological G. crista forms and different physico-chemical properties of water

The implications of the impact of the recreational use of forest mining ponds on benthic invertebrates with special emphasis on gastropods

The relationships between the distribution and diversity patterns of benthic invertebrates in forest ponds used for different recreational activities were examined in this study. The study was based on sampling of benthic invertebrates, plant coverage, physical and chemical analysis of water samples and multivariate species analysis. Mining ponds varied in their solution chemistry and plant cover, with those used for recreation having significantly lower invertebrate occurrences (755 ind. m−2) compared to ponds with no recreational use (2629 ind. m−2). Statistically significant differences were also observed in the density of Oligochaeta, Hirudinea, Coleoptera, Trichoptera and Diptera between the two types of ponds. Overall, gastropods were more diverse and abundant in ponds not used for recreation. This appeared to relate strongly to plant cover, since cover was greatly reduced in recreational ponds, although plant diversity was enhanced. Density and diversity of benthic invertebrates was also observed to differ in relation to the kind of recreational use involved (recreational angling, swimming, power boating) although this was not quantified. The occurrence of freshwater snails primarily depended on the Ca concentration, the conductivity of the water and plant cover, but recreational disturbance appeared to reduce abundance where it occurred and was related to a reduction in overall plant cover

Identifying factors linked to the occurrence of alien gastropod in isolated woodland water bodies

Biological invasions are a significant component of human-caused global change and is widely regarded as one of the main threats to natural biodiversity. Isolated anthropogenic water bodies created in the areas that are deprived of natural freshwater habitats allow the survival and reproduction of alien species on newly settled sites. They are often small with water level fluctuations causing frequent environmental disturbances. The colonisation success may be the result of the rate of their degradation. The aims of the study were to determine the environmental conditions that affect the existence of alien species of gastropods in this type of aquatic environment and to examine whether the occurrence of non-native species affects the community structure of the native species. This study made it possible to group woodland ponds according to the occurrence of the three invasive species in snail communities and discuss the environmental conditions present in these pond types. Analysis of water properties emphasised the distinctiveness of the selected pond types. In ponds of the Potamopyrgus antipodarum type, we found the highest values of some parameters mainly hardness, conductivity, and content of calcium and chlorides, in contrast with the Physella acuta type, which were characterised by the lowest values except for phosphates and nitrites. In the Ferrissia fragilis type, we found the highest nitrate content. Data on the occurrence of alien species in different water environments play an important role in actions which are taken to prevent new invasions and spread of non-native species as well as to reduce future impacts of invaders