Using Knowledge Management Technology to Aid Knowledge Transfer

This paper describes a practical system designed to create, maintain and manage teaching materials using knowledge management techniques. This system uses ISO Topic Maps to represent and store knowledge, which subsequently are accessed online or converted into multiple forms suitable for use as lecture materials. The benets of such a generic semantic knowledge store that represents information in a shallow and concise fashion include the ease of selecting pertinent material and of any subsequent transformation into presentations and lecture materials. Separating content lters and presentation rendering from the actual knowledge also allows for very ecient long-term maintenance of the knowledge. This environment has evolved over the last six years and become a major factor in reducing the eorts necessary to keep course materials up to date where the subjects cover fast-changing, emerging technologies and therefore require frequent revision. Our knowledge management approach to maintaining teaching materials also suggested itself as a novel assessment format: in advanced subjects we have had quite positive experiences with tasking students with research exercises where the deliverable is such a topic map instead of the more common essay format. This paper gives an overview of our integrated environment and outlines the benets and positive results we have experienced with its use for teaching purposes

Tamper-Resistant Peer-to-Peer Storage for File Integrity Checking.

“... oba es gibt kan Kompromiß, zwischen ehrlich sein und link, a wann’s no so afoch ausschaut, und wann’s noch so üblich is...” — Wolfgang Ambros, 1975 One of the activities of most successful intruders of a computer system is to modify data on the victim, either to hide his/her presence and to destroy the evidence of the break-in, or to subvert the system completely and make it accessible for further abuse without triggering alarms. File integrity checking is one common method to mitigate the effects of successful intrusions by detecting the changes an intruder makes to files on a computer system. Historically file integrity checking has been implemented using tools that operate locally on a single system, which imposes quite some restrictions regarding maintenance and scalability. Recent improvements for large scale environments have introduced trusted central servers which provide secure fingerprint storage and logging facilities, but such centralism presents some new shortcomings

Identical Mutation in a Novel Retinal Gene Causes Progressive Rod-Cone Degeneration in Dogs and Retinitis Pigmentosa in Humans

Progressive rod–cone degeneration (prcd) is a late-onset, autosomal recessive photoreceptor degeneration of dogs and a homolog for some forms of human retinitis pigmentosa (RP). Previously, the disease-relevant interval was reduced to a 106-kb region on CFA9, and a common phenotype-specific haplotype was identified in all affected dogs from several different breeds and breed varieties. Screening of a canine retinal EST library identified partial cDNAs for novel candidate genes in the disease-relevant interval. The complete cDNA of one of these, PRCD, was cloned in dog, human, and mouse. The gene codes for a 54-amino-acid (aa) protein in dog and human and a 53-aa protein in the mouse; the first 24 aa, coded for by exon 1, are highly conserved in 14 vertebrate species. A homozygous mutation (TGC → TAC) in the second codon shows complete concordance with the disorder in 18 different dog breeds/breed varieties tested. The same homozygous mutation was identified in a human patient from Bangladesh with autosomal recessive RP. Expression studies support the predominant expression of this gene in the retina, with equal expression in the retinal pigment epithelium, photoreceptor, and ganglion cell layers. This study provides strong evidence that a mutation in the novel gene PRCD is the cause of autosomal recessive retinal degeneration in both dogs and humans

Response of Sunflower (Helianthus annuus L.) Leaf Surface Defenses to Exogenous Methyl Jasmonate

Helianthus annuus, the common sunflower, produces a complex array of secondary compounds that are secreted into glandular trichomes, specialized structures found on leaf surfaces and anther appendages of flowers. The primary components of these trichome secretions are sesquiterpene lactones (STL), a diverse class of compounds produced abundantly by the plant family Compositae and believed to contribute to plant defense against herbivory. We treated wild and cultivated H. annuus accessions with exogenous methyl jasmonate, a plant hormone that mediates plant defense against insect herbivores and certain classes of fungal pathogens. The wild sunflower produced a higher density of glandular trichomes on its leaves than the cultivar. Comparison of the profiles of glandular trichome extracts obtained by liquid chromatography–mass spectroscopy (LC-MS) showed that wild and cultivated H. annuus were qualitatively similar in surface chemistry, although differing in the relative size and proportion of various compounds detected. Despite observing consistent transcriptional responses to methyl jasmonate treatment, we detected no significant effect on glandular trichome density or LC-MS profile in cultivated or wild sunflower, with wild sunflower exhibiting a declining trend in overall STL production and foliar glandular trichome density of jasmonate-treated plants. These results suggest that glandular trichomes and associated compounds may act as constitutive defenses or require greater levels of stimulus for induction than the observed transcriptional responses to exogenous jasmonate. Reduced defense investment in domesticated lines is consistent with predicted tradeoffs caused by selection for increased yield; future research will focus on the development of genetic resources to explicitly test the ecological roles of glandular trichomes and associated effects on plant growth and fitness

The Present and Future Role of Insect-Resistant Genetically Modified Maize in IPM

Commercial, genetically-modified (GM) maize was first planted in the United States (USA, 1996) and Canada (1997) but now is grown in 13 countries on a total of over 35 million hectares (\u3e24% of area worldwide). The first GM maize plants produced a Cry protein derived from the soil bacteriumBacillus thuringiensis (Bt), which made them resistant to European corn borer and other lepidopteran maize pests. New GM maize hybrids not only have resistance to lepidopteran pests but some have resistance to coleopteran pests and tolerance to specific herbicides. Growers are attracted to the Btmaize hybrids for their convenience and because of yield protection, reduced need for chemical insecticides, and improved grain quality. Yet, most growers worldwide still rely on traditional integrated pest management (IPM) methods to control maize pests. They must weigh the appeal of buying insect protection “in the bag” against questions regarding economics, environmental safety, and insect resistance management (IRM). Traditional management of maize insects and the opportunities and challenges presented by GM maize are considered as they relate to current and future insect-resistant products. Four countries, two that currently have commercialize Bt maize (USA and Spain) and two that do not (China and Kenya), are highlighted. As with other insect management tactics (e.g., insecticide use or tillage), GM maize should not be considered inherently compatible or incompatible with IPM. Rather, the effect of GM insect-resistance on maize IPM likely depends on how the technology is developed and used

A critical appraisal of appendage disparity and homology in fishes

Fishes are both extremely diverse and morphologically disparate. Part of this disparity can be observed in the numerous possible fin configurations that may differ in terms of the number of fins as well as fin shapes, sizes and relative positions on the body. Here, we thoroughly review the major patterns of disparity in fin configurations for each major group of fishes and discuss how median and paired fin homologies have been interpreted over time. When taking into account the entire span of fish diversity, including both extant and fossil taxa, the disparity in fin morphologies greatly complicates inferring homologies for individual fins. Given the phylogenetic scope of this review, structural and topological criteria appear to be the most useful indicators of fin identity. We further suggest that it may be advantageous to consider some of these fin homologies as nested within the larger framework of homologous fin‐forming morphogenetic fields. We also discuss scenarios of appendage evolution and suggest that modularity may have played a key role in appendage disparification. Fin modules re‐expressed within the boundaries of fin‐forming fields could explain how some fins may have evolved numerous times independently in separate lineages (e.g., adipose fin), or how new fins may have evolved over time (e.g., anterior and posterior dorsal fins, pectoral and pelvic fins). We favour an evolutionary scenario whereby median appendages appeared from a unique field of competence first positioned throughout the dorsal and ventral midlines, which was then redeployed laterally leading to paired appendages.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151971/1/faf12402_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151971/2/faf12402.pd

Keratin: Structure, mechanical properties, occurrence in biological organisms, and efforts at bioinspiration

A ubiquitous biological material, keratin represents a group of insoluble, usually high-sulfur content and filament-forming proteins, constituting the bulk of epidermal appendages such as hair, nails, claws, turtle scutes, horns, whale baleen, beaks, and feathers. These keratinous materials are formed by cells filled with keratin and are considered 'dead tissues'. Nevertheless, they are among the toughest biological materials, serving as a wide variety of interesting functions, e.g. scales to armor body, horns to combat aggressors, hagfish slime as defense against predators, nails and claws to increase prehension, hair and fur to protect against the environment. The vivid inspiring examples can offer useful solutions to design new structural and functional materials. Keratins can be classified as α- and β-types. Both show a characteristic filament-matrix structure: 7 nm diameter intermediate filaments for α-keratin, and 3 nm diameter filaments for β-keratin. Both are embedded in an amorphous keratin matrix. The molecular unit of intermediate filaments is a coiled-coil heterodimer and that of β-keratin filament is a pleated sheet. The mechanical response of α-keratin has been extensively studied and shows linear Hookean, yield and post-yield regions, and in some cases, a high reversible elastic deformation. Thus, they can be also be considered 'biopolymers'. On the other hand, β-keratin has not been investigated as comprehensively. Keratinous materials are strain-rate sensitive, and the effect of hydration is significant. Keratinous materials exhibit a complex hierarchical structure: polypeptide chains and filament-matrix structures at the nanoscale, organization of keratinized cells into lamellar, tubular-intertubular, fiber or layered structures at the microscale, and solid, compact sheaths over porous core, sandwich or threads at the macroscale. These produce a wide range of mechanical properties: the Young's modulus ranges from 10 MPa in stratum corneum to about 2.5 GPa in feathers, and the tensile strength varies from 2 MPa in stratum corneum to 530 MPa in dry hagfish slime threads. Therefore, they are able to serve various functions including diffusion barrier, buffering external attack, energy-absorption, impact-resistance, piercing opponents, withstanding repeated stress and aerodynamic forces, and resisting buckling and penetration. A fascinating part of the new frontier of materials study is the development of bioinspired materials and designs. A comprehensive understanding of the biochemistry, structure and mechanical properties of keratins and keratinous materials is of great importance for keratin-based bioinspired materials and designs. Current bioinspired efforts including the manufacturing of quill-inspired aluminum composites, animal horn-inspired SiC composites, and feather-inspired interlayered composites are presented and novel avenues for research are discussed. The first inroads into molecular-based biomimicry are being currently made, and it is hoped that this approach will yield novel biopolymers through recombinant DNA and self-assembly. We also identify areas of research where knowledge development is still needed to elucidate structures and deformation/failure mechanisms

Landslide characterisation based on multi-temporal terrestrial laser scanning in the cirque of the Austre Lovénbreen

International audienceThe slopes surrounding the Austre Lovénbreen glacier (79 • N, Ny-Alesund, Svalbard) were selected to study the occurrence, spatial distribution and temporal evolution of landslide processes in the high arctic. In addition, the impact of ongoing glacier retreat and warming-induced permafrost degradation on landslide formation mechanisms is investigated by analyses of multi-temporal terrestrial laser scanning (TLS) data and geological field surveys. The cirque of Austre Lovénbreen glacier is located in the basement rocks of the Kongsvegen Group which is composed of the Nielsenfjellet, Steenfjellet and the Bogegga Formation. For this study particular focus is placed on low strength and penetrative foliated phyllites of the Nielsenfjellet Formation. The area was chosen because this rock type is prone for different landslide processes including deep-seated rock slides, shallow soil slides, solifluction, rock avalanches and falls. In the study area, the landslide inventory was mapped during a field survey in 2017 and by the analysis of multi-temporal TLS data. TLS was performed annually since 2012 and provide high resolution digital elevation models of the slopes and thus enable the detection of topographical changes induced by landslides. Ortho-images, aerial photographs taken since 1936 and ground based photographs taken during the field campaign provide additional information about the different slope processes. With the help of differential maps derived from terrestrial laser scanning and photogrammetric models slope and landslide processes are identified and mapped using geographic information systems. During the field campaign several shallow translational soil slides with depths ranging from 1-5 m were observed. The basal shear zones of the soil slides were formed directly on the contact between the soil layer and an underlaying glacier ice layer. The frequently occurrence of these type of failure mechanisms at different heights of the slopes shows that the underlaying ice layer can be found up to 100 m above the Austre Lovénbreen valley glacier as was shown through previous GPR studies conducted in the area. Field observations suggest that formation of the shallow soil slides is related to a mass loss of the valley glacier i.e. loss of the retaining effect at the foot and/or the reduction of shear strength at the contact between the soil and ice layer most probably due to temperature increase and water infiltration. Furthermore, on all slopes solifluction sheets and lobes were observed indicating active shallow soil creep. Surprisingly, no characteristic structures indicating deep-seated rock slides were found in the area even though the slopes are steep and composed of intensively fractured low-strength phyllitic rock masses. The presented study provides a preliminary insight into landslide processes that occur in slopes of the high arctic affected by glacier retreat and permafrost degradation

Landslide monitoring using multi-temporal terrestrial laser scanning(TLS) and electrical resistivity tomography (ERT) in the high Arctic,Ny-Ålesund

International audienceThe acceleration of climate-induced changes in high arctic environments is evident and lead to a wide range ofprocesses (e.g. glacier retreat, landslide activity). Recent studies (Bernard et al. 2014) provide evidence that, thestability of the talus covered slopes is reducing and thus landslides are occurring more frequently on the slopessurrounding the Austre Lovénbreen glacier.The Austre Lovénbreen glacier basin is a relatively small arctic glacier basin located at 79◦N, Ny-Ålesund(Svalbard) and geologically is part of the Kongsvegen Group, which is composed of the Nielsenfjellet, Steenfjelletand the Bogegga Formation. This study focusses on the quantitative and spatiotemporal identification of shallowtranslational soil slides (i.e. debris slides, Hungr et al. 2014) originating from the talus-covered slopes of theperiglacial valley system.The assessment of the soil slides on the slopes of the Austre Lovénbreen basin was performed i) by geo-logical field surveys (09/2017, 09/2018), ii) by terrestrial laser scanning (TLS) campaigns measuring more than300 single laser scans (08/2012, 08/2013, 08/2014, 08/2015, 08/2016, 09/2017, 09/2018), and iii) by electricalresistivity tomography (ERT) in order to perform subsurface investigations (09/2018).The results provide insights into the slide geometry, thickness, volume, as well as time of formation anddeformation behaviour. Data show that since 2012 several soil slides in the range between 500 m3 und 5000 m3have failed on the steeply inclined (35-42◦) talus slopes. In many cases the failure surface was formed at thecontact between the talus material and a subsurface ice layer, which is covered by the talus deposits. Interestingly,the ice layers extent up to 100 m above the present-day Austre Lovénbreen glacier surface in the basin. The icelayer was also detectable by previous ground penetrating radar (GPR) studies, and if exposed by slides, alsovisible by TLS measurements (reflectivity), webcam images and field surveys. The subsurface ice, acting as afailure surface, limits the slide thickness to values between 1 and 5 m.Concerning trigger mechanisms, rainfall data in combination with the webcam images suggests that theformation of the shallow soil slides is related to intense rainfall events and furthermore to the mass loss of thevalley glacier reducing the retaining effect at the foot.The results contribute to better understanding of recent changes in high arctic landscape systems and maygive further indications on future landslide activity in the high arctic