Isogeometric analysis applied to frictionless large deformation elastoplastic contact

This paper focuses on the application of isogeometric analysis to model frictionless large deformation contact between deformable bodies and rigid surfaces that may be represented by analytical functions. The contact constraints are satisfied exactly with the augmented Lagrangian method, and treated with a mortar-based approach combined with a simplified integration method to avoid segmentation of the contact surfaces. The spatial discretization of the deformable body is performed with NURBS and C0-continuous Lagrange polynomial elements. The numerical examples demonstrate that isogeometric surface discretization delivers more accurate and robust predictions of the response compared to Lagrange discretizations

The nature of entrepreneurs’ engagement with a layered rural context

Rural entrepreneurship has recently been reconceptualised as engagement with contexts. However, our knowledge of the nature of this engagement remains limited. In this paper, we explore the engagement of entrepreneurs hired as part-time industry mentors at regional universities. Using a qualitative approach based on grounded theory and self-ethnography, we interviewed five entrepreneurs in adjunct positions and their academic counterparts at universities in Northern Norway. We also relied on our own experience as academics collaborating with industry mentors. Our findings demonstrate that the entrepreneurs’ engagement encompasses and combines the business, academic and spatial layers of the entrepreneurs’ context and that it unfolds in the form of knowledge-sharing practices. Our study makes several contributions. First, it contributes to the limited empirical research on rural entrepreneurship as engagement with context and gives a novel and detailed account of how this engagement unfolds in practice. Second, it contributes by adding new insight into how entrepreneurs relate to a layered rural context. In particular, we emphasise that the knowledge-sharing practices help in crossing boundaries between the layers. Third, our study offers some practical contributions for rural entrepreneurs, policymakers and actors in regional innovation systems and regional universities

Analysis of acute brain slices by electron microscopy: A correlative light-electron microscopy workflow based on Tokuyasu cryo-sectioning.

Acute brain slices are slices of brain tissue that are kept vital in vitro for further recordings and analyses. This tool is of major importance in neurobiology and allows the study of brain cells such as microglia, astrocytes, neurons and their inter/intracellular communications via ion channels or transporters. In combination with light/fluorescence microscopies, acute brain slices enable the ex vivo analysis of specific cells or groups of cells inside the slice, e.g. astrocytes. To bridge ex vivo knowledge of a cell with its ultrastructure, we developed a correlative microscopy approach for acute brain slices. The workflow begins with sampling of the tissue and precise trimming of a region of interest, which contains GFP-tagged astrocytes that can be visualised by fluorescence microscopy of ultrathin sections. The astrocytes and their surroundings are then analysed by high resolution scanning transmission electron microscopy (STEM). An important aspect of this workflow is the modification of a commercial cryo-ultramicrotome to observe the fluorescent GFP signal during the trimming process. It ensured that sections contained at least one GFP astrocyte. After cryo-sectioning, a map of the GFP-expressing astrocytes is established and transferred to correlation software installed on a focused ion beam scanning electron microscope equipped with a STEM detector. Next, the areas displaying fluorescence are selected for high resolution STEM imaging. An overview area (e.g. a whole mesh of the grid) is imaged with an automated tiling and stitching process. In the final stitched image, the local organisation of the brain tissue can be surveyed or areas of interest can be magnified to observe fine details, e.g. vesicles or gold labels on specific proteins. The robustness of this workflow is contingent on the quality of sample preparation, based on Tokuyasu's protocol. This method results in a reasonable compromise between preservation of morphology and maintenance of antigenicity. Finally, an important feature of this approach is that the fluorescence of the GFP signal is preserved throughout the entire preparation process until the last step before electron microscopy

Elg som næring : elgarbeid på Evenstad 1995 – 2013

I 1995 byrja me å studera elg og trafikk i Østerdalen. Då ulv etablerte seg i studieområdet, undersøkte me verknaden av ulv på elg. Sidan studerte me elgøkonomi før me såg på verknaden av elgfôring i samarbeid med Stor-Elvdal Grunneierforening, Løvenskiold-Fossum og Fritzøe Skoger. No arbeider me med samordna forvalting av skog og elg, der me prøver ut ordinære skogbrukstiltak som skal gje elgen meir fôr og skogeigaren uskadde furuforyngingar. I alt har me radiomerka 268 elgar, og me har studert elg og vegetasjon i felt. Me gjev her ei grov oversikt over resultata frå det vitskaplege arbeidet med elg på Evenstad, gjev forvaltningsråd basert på dette og viser kva me vil arbeida med framover. Hovudfokus i heile perioden har vore å sjå på elgen som ein ressurs. Arbeidstittelen har vore Elg som næring. Elg er mykje meir enn næring, men i denne artikkelen ser me på elgen hovudsakleg i næringsmessig samanheng sett med lokaløkonomiske auger

Hospital treatment -is it affordable? A structured cost analysis of vaginal deliveries and planned caesarean sections

<p>Abstract</p> <p>Introduction</p> <p>The analysis of cost effectiveness in hospitals is as difficult as treating the patients properly. We are yet not able to answer the simple question of what costs are caused by a certain diagnosis and its treatment during an average hospital stay.</p> <p>Methods</p> <p>To answer some issues of the global problem of cost effectiveness during hospitalisation, we analysed the costs and the cost structure of a normal obstetrical hospital stay during an uncomplicated vaginal delivery and a planned caesarean section. Cost data was collected and summarized from the patients file, the hospital's computer system gathering all cost centres, known material expenses and expenses of non obstetrical medical services.</p> <p>Results</p> <p>For vaginal deliveries/planned caesareans we can calculate with a surplus of about 83 €/1432 €. About 45% of the summarized costs are calculated on a reliable database.</p> <p>Discussion</p> <p>The introduction of the DRG based clearing system in Germany has aggravated the discussion on cost effectiveness. Our meticulous work-up of expenses excluded personal precautionary costs and personnel costs of documentation because no tools are described to depict such costs. If we would add these costs to the known expenses of our study, we strongly suspect that hospital treatment of vaginal deliveries or planned caesarean sections is not cost effective.</p

Omentum is highly effective in the management of complex cardiothoracic surgical problems

AbstractObjectives: Vascularized, pedicled tissue flaps are often used for cardiothoracic surgical problems complicated by factors that adversely affect healing, such as previous irradiation, established infection, or steroid use. We reviewed our experience with use of the omentum in these situations to provide a yardstick against which results with other vascularized flaps (specifically muscle flaps) could be compared. Methods: A retrospective review was undertaken of 85 consecutive patients in whom omentum was used in the chest. In 47 patients (group I), use of omentum was prophylactic to aid in the healing of closures or anastomoses considered to be at high risk for failure. In 32 patients (group II), omentum was used in the treatment of problems complicated by established infection. In 6 patients (group III), omentum was used for coverage of prosthetic chest wall replacements after extensive chest wall resection. Results: Overall, omental transposition was successful in its prophylactic or therapeutic purpose in 88% of these difficult cases (75/85). Success with omentum was achieved for 89% of patients (42/47) in group I, 91% of patients (29/32) in group II, and 67% of patients (4/6) in group III. Three patients (3.5%) had complications of omental mobilization. Four patients (4.7%) died after the operation as a result of failure of the omentum to manage the problem for which it was used. Conclusions: Results with omental transposition compare favorably with published series of similarly challenging cases managed with muscle transposition. Complications of omental mobilization are rare. We believe that its unique properties render the omentum an excellent choice of vascularized pedicle in the management of the most complex cardiothoracic surgical problems.J Thorac Cardiovasc Surg 2003;125:526-3

The Methylococcus capsulatus (Bath) Secreted Protein, MopE*, Binds Both Reduced and Oxidized Copper

Under copper limiting growth conditions the methanotrophic bacterium Methylococcus capsulatus (Bath) secrets essentially only one protein, MopE*, to the medium. MopE* is a copper-binding protein whose structure has been determined by X-ray crystallography. The structure of MopE* revealed a unique high affinity copper binding site consisting of two histidine imidazoles and one kynurenine, the latter an oxidation product of Trp130. In this study, we demonstrate that the copper ion coordinated by this strong binding site is in the Cu(I) state when MopE* is isolated from the growth medium of M. capsulatus. The conclusion is based on X-ray Near Edge Absorption spectroscopy (XANES), and Electron Paramagnetic Resonance (EPR) studies. EPR analyses demonstrated that MopE*, in addition to the strong copper-binding site, also binds Cu(II) at two weaker binding sites. Both Cu(II) binding sites have properties typical of non-blue type II Cu (II) centres, and the strongest of the two Cu(II) sites is characterised by a relative high hyperfine coupling of copper (

Dynamical models for sand ripples beneath surface waves

We introduce order parameter models for describing the dynamics of sand ripple patterns under oscillatory flow. A crucial ingredient of these models is the mass transport between adjacent ripples, which we obtain from detailed numerical simulations for a range of ripple sizes. Using this mass transport function, our models predict the existence of a stable band of wavenumbers limited by secondary instabilities. Small ripples coarsen in our models and this process leads to a sharply selected final wavenumber, in agreement with experimental observations.Comment: 9 pages. Shortened version of previous submissio