Concurrent Sessions C: Multi-Dimensional Modeling and Fish Passage Restoration - Some Aspects of Fish Behaviour and Hydraulics Which May Affect Passage Effectiveness

Fish behaviour over space, time, life cycle needs and ecohydraulic conditions may affect the effectiveness of upstream and downstream passage systems. The spacial extent of migratory movements may depend on whether available and suitable habitat which meets the life cycle needs of specific species exists only below or only above a barrier, or in both locations. Highly effective passage systems have the following characteristics: a) their use is compelled by the migratory needs of specific species ;b) are easy to locate by the migratory fish community as they offer topographical and flow conditions that species seek rather than avoid; and c) combine morphological features and hydrodynamic conditions which match their biomechanical capabilities and are suitable for efficient transport. These factors relate to species motivation (required versus tentative movements), attraction or guidance efficiency (probability that fish will locate the upstream fishway entrance or be actively guided downstream), and passage efficiency (probability fish will move through passage system), respectively. Any one of these factors or any combination of the three may limit overall system passage effectiveness. Field assessments for several species and many passage systems around the globe, supplemented by controlled laboratory studies, have demonstrated considerable variation in attraction or guidance efficiency, as well as passage efficiency. Not surprisingly, biological factors, such as migratory, morphological or ecological characteristics of different species, species abilities, salmonids vs non-salmonids, as well as passage system design features, such as dimensions, velocities, turbulence and appropriate flows, are important. Although available field assessments are based on limited and often non-standardized data, they provide evidence that attraction or guidance efficiency may depend more (but not exclusively) on biological factors. Field and laboratory studies indicate that passage efficiency may depend more (but not exclusively) on passage system design features, particularly when biological requirements and hydraulic conditions are well matched. Although frequently not well understood or quantified, species motivation and use of habitat below or above barriersmay also affect attraction, guidance and passage efficiency, as fish may utilize fish passage systems for tentative rather than required movements. Innovative fish tracking techniques in field and laboratory studies are providing ways to quantify motivation, attraction/guidance, and passage factors. Ecohydraulic approaches, which integrate improved biological assessments with advanced hydraulics, enhance understanding of fish behaviour and the factors affecting passage effectiveness. Responses of downstream moving fish associated with spillway re-design, bypasses, and bar racks or upstream moving fish associated with habitat use, attraction efficiency to fishway entrances and passage efficiency through submerged orifices or surface weirs or different turbulence characteristics in pools are highlighted. Results of such ecohydraulic studies are invaluable in calibrating numerical simulations and enhancing biological ground-truthing of CFD modeling for 1, 2 or 3 dimensions. Such modeling may provide additional insights about turbulent flow and fish behaviour. Much more effort on ecohydraulic studies is needed in the field and in the laboratory to quantify responses of species with different migratory needs and biomechanical capabilities. This effort is needed to further improve knowledge, validate fish behaviour assumptions, ground-truth models and assist the development of more robust and effective fish passage systems

Session B9: Size Matters Even for the Ubiquitous Fish Speed Metric of BL/S

Abstract: The use of BL/s, i.e. body lengths per second (dimensions of s-1), to express relative swim speeds for fish is very common. The physiological literature demonstrates the following: a) fish length is a strong predictor of swimming performance; b) longer fish achieve higher absolute swim speeds (dimensions of m/s) than shorter ones, at least for the same species; c) when swim speeds are expressed in BL/s, shorter fish have higher relative speeds than longer ones. Therefore, it is difficult to estimate swim speeds of large fish from small fish and vice versa, when using these absolute or relative swim speed metrics. It is important to recognize that regressions with data from small fish (e.g. juveniles) expressed in BL/s, would lead to overestimates of absolute swim speeds for large fish. It also follows that BL/s regressions with data from large fish, would lead to underestimates of absolute swim speeds for small fish. Yet, costs and complexity often lead to considerable data sets for small fish and limited tests with large fish, even though swim speed estimates are frequently needed for large fish. Regression strength for the same data sets, is higher when using dimensionless swim speed expressions, rather than BL/s. Such ecohydraulic analyses, demonstrate swimming performance similarity between small and large fish and provide better absolute swim speed estimates. Furthermore, ecohydraulic analyses point to efficient strategies for testing length classes, particularly when swim speeds for considerable numbers of sizes and species are needed

Towards hybrid cloud service certification models

In this paper, we introduce a hybrid approach for certifying security properties of cloud services that combines monitoring and testing data. The paper argues about the need for hybrid certification and examines some basic characteristics of hybrid certification models

Does having a baby affect tenants’ renting opportunities? Experimental evidence from NYC

Access to reliable and stable housing is critical for the general population in urban areas and large cities. This paper tests for differential treatment in the rental housing market using an experiment conducted via e-mail for rental units advertised on-line. There are two emails with the same content, except for one shows the family status as childless and the other shows the family status as having an 18-month-old child. These emails were then sent to the landlords with an equal distribution. Apart from family status, there is no mention of socioeconomic status or any other identifying factors of the tenant. This study was conducted in the borough of Queens, New York. The findings of the study indicated a ten percentage point increase in responses when there were no children in the correspondence for both one bedroom and two bedroom apartments

Trafficking and localization studies of recombinant α1,3-fucosyltransferase VI stably expressed in CHO cells

Peripheral α1,3-fucosylation of glycans occurs by the action of either one of five different α1,3-fucosyltransferases (Fuc-Ts) cloned to date. Fuc-TVI is one of the α1,3-fucosyltransferases which is capable to synthesize selectin ligands. The major α1,3-fucosyltransferase activity in human plasma is encoded by the gene for fucosyltransferase VI, which presumably originates from liver cells. While the sequence, chromosomal localization, and kinetic properties of Fuc-TVI are known, immunocytochemical localization and trafficking studies have been impossible because of the lack of specific antibodies. Here we report on the development and characterization of a peptide-specific polyclonal antiserum mono-specific to Fuc-TVI and an antiserum to purified soluble recombinant Fuc-TVI crossreactive with Fuc-TIII and Fuc-TV. Both antisera were applied for immunodetection in stably transfected CHO cells expressing the full-length form of this enzyme (CHO clone 61/11). Fuc-TVI was found to be a resident protein of the Golgi apparatus. In addition, more than 30% of cell-associated and released enzyme activity was found in the medium. Maturation and release of Fuc-TVI was analyzed in metabolically labeled CHO 61/11 cells followed by immunoprecipitation. Fuc-TVI occurred in two forms of 47 kDa and 43 kDa bands, while the secreted form was detected as a 43 kDa. These two different intracellular forms arose by posttranslational modification, as shown by pulse-chase experiments. Fuc-TVI was released to the supernatant by proteolytic cleavage as a partially endo-H resistant glycofor

Hybrid cloud security certification

In this report, I introduce a hybrid approach for certifying security properties of cloud services that combines monitoring and testing data. This report argues about the need for hybrid certification and examines the basic characteristics of hybrid certification models. The certification of cloud service security has become a necessity due to the on-going concerns about cloud security and the need to increase cloud trustworthiness through rigorous assessments of security by trusted third parties. Unlike the certification of security in traditional software systems, which is based on static forms of security assessment (e.g., the Common Criteria model), the certification of cloud service security requires continuous assessment. This is because cloud services are provisioned through dynamic infrastructures operating under security controls and other configurations that may change dynamically introducing unforeseen vulnerabilities. Cloud service security can also be compromised because of attacks on co-tenant services. Recent work on cloud service certification applies dynamic forms of security assessment, notably dynamic testing or continuous monitoring. These overcome some of the limitations of traditional security certification and audits (e.g. they produce machine readable certificates incorporating dynamically collected evidence). However, there are cases where existing approaches cannot provide an adequate level of assurance. Testing, for instance, may be insufficient for transactional services, as it is normally performed through a special testing (as opposed to the operational) service interface. Monitoring-based certification may also be insufficient if there is conflicting or inconclusive evidence in monitoring data; such data may, for example, not cover all traces of system events that should be seen to assess a property. To overcome such problems, I am working on a hybrid approach for certifying cloud service security that can combine both monitoring and testing evidence. For that reason, I designed a new cloud certification approach supporting the automated and continuous certification of security properties of cloud services based on the combination of dynamically acquired testing and monitoring evidence that can deliver the high level of assurance and can overcome the limitations of assessments based on each of these types of evidence in isolation. My approach is based on the cloud certification framework of the CUMULUS EU FP7 project

Ecological Characteristics of Streams in the Barrenlands near Lac de Gras, N.W.T., Canada

We examined spatiotemporal variation in the physical, chemical, and biological characteristics of pristine streams that represent a range of conditions near Lac de Gras in the Barrenlands region of the Northwest Territories, Canada. Principal component analysis organized streams into four groups on the basis of seven physical characteristics. Despite broad differences among groups in physical characteristics, variation in chemical and biological characteristics was generally not large, with only pH and coarse particulate organic matter differing among the four groups. Nevertheless, several chemical and biological variables were correlated with physical characteristics, particularly measures of stream size (bankfull width and depth, drainage area, and stream discharge). Annual variability in climate affected stream temperature and discharge and influenced several biotic characteristics, particularly the growth of young-of-the-year arctic grayling (Thymallus arcticus). Barrenland streams share basic characteristics of Alaskan tundra streams, as a result of similar climatic regimes. Key differences between the two areas, however, appear related to the lake-outlet nature of the Barrenland streams, which may contribute to higher growth of young-of-the-year arctic grayling than would be expected from regional climate.On a étudié la variation spatio-temporelle dans les caractéristiques physiques, chimiques et biologiques de cours d'eau vierges qui témoignent d'une gamme de conditions près du lac de Gras dans la région des Barrenlands, dans les Territoires du Nord-Ouest, au Canada. L'analyse des composantes principales a divisé les cours d'eau en quatre groupes, d'après sept caractéristiques physiques. En dépit de différences marquées dans ces dernières entre les groupes, la variation dans les attributs chimiques et biologiques n'était généralement pas très grande, avec seulement le pH et les grosses particules organiques qui montraient des différences entre les quatre groupes. Plusieurs variables chimiques et biologiques étaient néanmoins corrélées avec les attributs physiques, en particulier les mesures de la taille des cours d'eau (largeur et profondeur du débordement, aire de drainage et débit). La variabilité annuelle du climat avait une incidence sur la température et le débit des cours d'eau et elle influençait plusieurs caractéristiques biotiques, en particulier la croissance des jeunes de l'année chez l'ombre arctique. Les cours d'eau des Barrenlands ont en commun les caractéristiques fondamentales des cours d'eau de la toundra alaskienne, vu qu'ils sont soumis à des régimes climatiques similaires. Les différences majeures entre les deux régions semblent cependant liées au fait que la décharge des cours d'eau des Barrenlands se fait dans un lac, ce qui pourrait contribuer à une croissance des jeunes de l'année chez l'ombre arctique plus forte que le climat régional ne le laisserait croire