191 research outputs found

    Floating debris as a design and analysis factor for bridges and culverts

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    Over the past ten years, the scientific community has focused a significant amount of attention on the accumulation and effects of floating debris at bridges and culverts. Two bridges failed catastrophically due to floating debris during the Upper Mississippi flooding of 1993 (Parola, et al, 1994). Various professional groups recognize the importance of Large Woody Debris (LWD), the primary component of floating debris, in riverine networks, yet no solid methodology exists for the quantification of floating debris and its hydraulic effects. This thesis aims to investigate the extent and hydraulic effects of floating debris at bridges and culverts throughout the United States, summarize the procedures for quantifying floating debris in rivers, and make recommendations for the establishment of a protocol for incorporating floating debris into the design and analysis process of bridges and culverts. State bridge engineering representatives were recently surveyed to determine opinions and data on drift-related problems, maintenance programs, and economic factors. Literature indicates three major steps are common in the analysis of floating debris: 1) evaluation of the potential quantity of floating debris delivered to the bridge or culvert site, 2) approximation of the quantity of floating debris accumulating at the site, and 3) hydraulic representation of the site incorporating the potential floating debris accumulation. The methods and models reviewed were the Diehl (1997) qualitative method of potential drift accumulation, the Debris at Bridge Pier Prediction Program (DBP3) (Wallerstein, 1999) for both quantification of potential drift accumulations and scour, and HEC-RAS (U.S. Army Corps of Engineers, 1998) for quantitative hydraulic values. A common opinion of state bridge engineers was formed from the survey results, indicating that the most efficient way to approach floating debris accumulations at bridges and culverts is to operate on a case-by-case basis at the local level. This approach, however, has led to a general failure to observe the costs associated with floating debris removal, repair of damages, and maintenance. The adoption of a consistent protocol for the quantification of floating debris accumulations has been hampered by the many site dependent variables associated with floating debris accumulations and their hydraulic effects at bridges and culverts, but one should be undertaken in order to guide engineers and modelers in the consideration of drift in the design and analysis process of hydraulic structures. An analysis protocol considering both qualitative and quantitative factors is presented to evaluate the potential hydraulic effects of floating debris, implementing flowcharts and computer models to guide the process

    Zoology

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    Presented at the fifth 2022 CNHP Partners' meeting, Conserving Biodiversity in a Changing Colorado, held on March 11, 2022 in the Grand Ballrooms C and D of the Lory Student Center, Colorado State University Campus, Fort Collins, Colorado

    EcoPrime twin – Scale-up of CaptureSMB to the process scale

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    Affinity chromatography is a powerful purification tool in pharmaceutical industry for capturing therapeutic proteins, in particular monoclonal antibodies (mAbs) and mAb fragments, from cell culture harvest. During the last years the resin utilization and productivity of affinity chromatography significantly improved due to the newly introduced multi-column continuous processes. The process setup was optimized to a twin-column continuous capture technology, known as CaptureSMB which requires less equipment hardware, has a less overall complexity and performs comparable if not better than other multi-column setups. This presentation outlines the CaptureSMB concept and focuses on the scale-up from bench-top to twin-column pilot scale. Especially, the focus is on the requirements for the equipment design, process automation and regulatory aspects due to the implementation of the continuous processing. Furthermore, future trends how the EcoPrime Twin technology will enable the integrated continuous downstream processin

    Sharpening the mesowear tool: geometric morphometric analysis of cusp shape and diet in ruminants

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    Mesowear is a dietary proxy that relates attritive wear and abrasive wear to the shape of worn tooth cusps of ungulates. Traditional mesowear methods categorize cusps according to relief and sharpness. A geometric morphometric approach has the potential to measure shape with higher precision and to discover unrecognized aspects of cusp shape, possibly improving the efficacy of mesowear. We quantified mesowear in extant Ruminantia, using a 2-D semilandmark outline technique on upper second molar metacones generated from photographs. Among the 91 species sampled, 65 were preassigned to dietary categories, browser, grazer, mixed feeder, and frugivore based on substantiated documentation of diet in the wildlife literature. Metacone cusp shape and metacone mesowear score were found to be independent of size. Principal component and discriminant function analyses of Procrustes transformed semilandmark coordinates revealed two diet-related components of cusp shape. The primary component is related to the traditional mesowear variables of cusp height and side steepness. The secondary shape component reveals variation in the mesiodistal symmetry of the metacone and may relate to a proal vector during the power stroke phase or the relative orientation of the cusps with respect to the chewing stroke vector. Discriminant function analysis of semilandmark data accurately classified the diets of species more frequently (67.2%) than the traditional mesowear method (56.1%). The semilandmark data successfully recognized the diets of grazing and browsing species with correct classification rates ranging from 69% to 95%. The diets of frugivorous and mixed feeding species were less frequently correctly recognized (33%–53%). Mixed feeding diets may be more difficult to recognize due to more heterogeneous diets when compared to browsers and grazers. Frugivores are more difficult to recognize because their rounded cusp apices resemble those of mixed feeders and grazers. We conclude that quantitative shape analysis improves the potential of mesowear. When used as a dietary proxy, we anticipate that mesowear analysis will correctly categorize the diets of most species. When misclassifications are made, they may most often be misclassifications of generalist mixed feeders and frugivores as either browsers or grazers

    A morphometric system to distinguish sheep and goat postcranial bones.

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    Distinguishing between the bones of sheep and goat is a notorious challenge in zooarchaeology. Several methodological contributions have been published at different times and by various people to facilitate this task, largely relying on a macro-morphological approach. This is now routinely adopted by zooarchaeologists but, although it certainly has its value, has also been shown to have limitations. Morphological discriminant criteria can vary in different populations and correct identification is highly dependent upon a researcher's experience, availability of appropriate reference collections, and many other factors that are difficult to quantify. There is therefore a need to establish a more objective system, susceptible to scrutiny. In order to fulfil such a requirement, this paper offers a comprehensive morphometric method for the identification of sheep and goat postcranial bones, using a sample of more than 150 modern skeletons as a basis, and building on previous pioneering work. The proposed method is based on measurements-some newly created, others previously published-and its use is recommended in combination with the more traditional morphological approach. Measurement ratios, used to translate morphological traits into biometrical attributes, are demonstrated to have substantial diagnostic potential, with the vast majority of specimens correctly assigned to species. The efficacy of the new method is also tested with Discriminant Analysis, which provides a successful verification of the biometrical indices, a statistical means to select the most promising measurements, and an additional line of analysis to be used in conjunction with the others

    A morphometric system to distinguish sheep and goat postcranial bones.

    Get PDF
    Distinguishing between the bones of sheep and goat is a notorious challenge in zooarchaeology. Several methodological contributions have been published at different times and by various people to facilitate this task, largely relying on a macro-morphological approach. This is now routinely adopted by zooarchaeologists but, although it certainly has its value, has also been shown to have limitations. Morphological discriminant criteria can vary in different populations and correct identification is highly dependent upon a researcher's experience, availability of appropriate reference collections, and many other factors that are difficult to quantify. There is therefore a need to establish a more objective system, susceptible to scrutiny. In order to fulfil such a requirement, this paper offers a comprehensive morphometric method for the identification of sheep and goat postcranial bones, using a sample of more than 150 modern skeletons as a basis, and building on previous pioneering work. The proposed method is based on measurements-some newly created, others previously published-and its use is recommended in combination with the more traditional morphological approach. Measurement ratios, used to translate morphological traits into biometrical attributes, are demonstrated to have substantial diagnostic potential, with the vast majority of specimens correctly assigned to species. The efficacy of the new method is also tested with Discriminant Analysis, which provides a successful verification of the biometrical indices, a statistical means to select the most promising measurements, and an additional line of analysis to be used in conjunction with the others

    Body Shape and Life Style of the Extinct Balearic Dormouse Hypnomys (Rodentia, Gliridae): New Evidence from the Study of Associated Skeletons

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    Hypnomys is a genus of Gliridae (Rodentia) that occurred in the Balearic Islands until Late Holocene. Recent finding of a complete skeleton of the chronospecies H. morpheus (Late Pleistocene-Early Holocene) and two articulated skeletons of H. cf. onicensis (Late Pliocene) allowed the inference of body size and the calculation of several postcranial indexes. We also performed a Factorial Discriminant Analysis (FDA) in order to evaluate locomotory behaviour and body shape of the taxa. Using allometric models based on skull and tooth measurements, we calculated a body weight between 173 and 284 g for H. morpheus, and direct measurements of articulated skeletons yielded a Head and Body Length (HBL) of 179 mm and a Total Body Length of 295 mm for this species. In addition to the generally higher robustness of postcranial bones already recorded by previous authors, H. morpheus, similar to Canariomys tamarani, another extinct island species, displayed elongated zygopodium bones of the limbs and a wider distal humerus and femur than in an extant related taxon, Eliomys quercinus. Indexes indicated that Hypnomys was more terrestrial and had greater fossorial abilities than E. quercinus. This was also corroborated by a Discriminant Analysis, although no clear additional inference of locomotory abilities could be calculated

    †Kenyaichthyidae fam. nov and †Kenyaichthys gen. nov - First Record of a Fossil Aplocheiloid Killifish (Teleostei, Cyprinodontiformes)

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    The extant Cyprinodontiformes (killifishes) with their two suborders Cyprinodontoidei and Aplocheiloidei represent a diverse and well-studied group of fishes. However, their fossil record is comparatively sparse and has so far yielded members of the Cyprinodontoidei only. Here we report on cyprinodontiform fossils from the upper Miocene Lukeino Formation in the Tugen Hills of the Central Rift Valley of Kenya, which represent the first fossil record of an aplocheiloid killifish. A total of 169 specimens - mostly extraordinarily well preserved and a sample of ten extant cyprinodontiform species were studied on the basis of morphometrics, meristics and osteology. A phylogenetic analysis using PAUP was also conducted for the fossils. Both the osteological data and the phylogenetic analysis provide strong evidence for the assignment of the fossils to the Aplocheiloidei, and justify the definition of the new family dagger Kenyaichthyidae, the new genus dagger Kenyaichthys and the new species dagger K. kipkechi sp. nov. The phylogenetic analysis unexpectedly places dagger Kenyaichthys gen. nov. in a sister relationship to the Rivulidae (a purely Neotropical group),a probable explanation might be lack of available synapomorphies for the Rivulidae, Nothobranchiidae and Aplocheilidae. The specimens of dagger K. kipkechi sp. nov. show several polymorphic characters and large overlap in meristic traits, which justifies their interpretation as a species flock in statu nascendi. Patterns of variation in neural and haemal spine dimensions in the caudal vertebrae of dagger Kenyaichthys gen. nov. and the extant species studied indicate that some previously suggested synapomorphies of the Cyprinodontoidei and Aplocheiloidei need to be revised
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