806 research outputs found
On numerically accurate finite element
A general criterion for testing a mesh with topologically similar repeat units is given, and the analysis shows that only a few conventional element types and arrangements are, or can be made suitable for computations in the fully plastic range. Further, a new variational principle, which can easily and simply be incorporated into an existing finite element program, is presented. This allows accurate computations to be made even for element designs that would not normally be suitable. Numerical results are given for three plane strain problems, namely pure bending of a beam, a thick-walled tube under pressure, and a deep double edge cracked tensile specimen. The effects of various element designs and of the new variational procedure are illustrated. Elastic-plastic computation at finite strain are discussed
Rechtsbescherming van uithuisgeplaatsten : een verkennend onderzoek
Nummer 5 in de Serie Bestuursrecht & Bestuurskunde Groningen
Expression of carbonic anhydrase IX suggests poor response to therapy in rectal cancer
Contains fulltext :
80703.pdf (publisher's version ) (Closed access
Logarithmic spin, logarithmic rate and material frame-indifferent generalized plasticity
In this work we present a new rate type formulation of large deformation generalized plasticity which is based on the consistent use of the logarithmic rate concept. For this purpose, the basic constitutive equations are initially established in a local rotationally neutralized configuration which is defined by the logarithmic spin. These are then rephrased in their spatial form, by employing some standard concepts from the tensor analysis on manifolds. Such an approach, besides being compatible with the notion of (hyper)elasticity, offers three basic advantages, namely:(i) The principle of material frame-indifference is trivially satisfied ; (ii) The structure of the infinitesimal theory remains essentially unaltered ; (iii) The formulation does not preclude anisotropic response. A general integration scheme for the computational implementation of generalized plasticity models which are based on the logarithmic rate is also discussed. The performance of the scheme is tested by two representative numerical examples
Schetsboek windturbines & ruimtelijke kwaliteit; landschappelijk onderzoek naar vides en concentratiegebieden
Dit schetsboek voor landschapsontwerp is gemaakt door Alterra, Bosch Slabbers tuin- en landschapsarchitecten en Buro Schöne, in opdracht van VROM, DG Ruimte. Deze landschapsvisie past in het kader van het Nationaal Plan van Aanpak Windenergi
Evaluation of ear, nose, and throat-screening in liver transplantation candidates:A retrospective cohort study
Background:Patients with end-stage liver disease can be treated with a liver transplantation (LT). Before listing, candidates are subjected to a screening procedure according to the EASL Clinical Practice Guidelines for LT. In our hospital, this includes an ear, nose, and throat (ENT) examination, directed towards the identification of (asymptomatic) infections and head and neck malignancies.Methods:We retrospectively reviewed all ENT screening examinations in LT candidates from 2007 to 2022. The screening consisted of a visit to the ENT outpatient clinic combined with sinus radiography.Results:ENT screening was performed in 1099 patients. Sixty-one cases were identified, either diagnosed with an infection (n = 58, almost exclusively sinusitis) or a neoplasm (n = 3, of which two malignancies). With binary logistic regression, we could not identify significant risk factors for diagnosing sinusitis. 711 patients underwent LT. After LT, two patients developed a novel malignancy of the head and neck area, while 14 patients were diagnosed with sinusitis, two of the latter already showed opacification on sinus radiography during screening. Despite immunosuppressive drugs, no complicated sinusitis was observed.Conclusion:Sinusitis or a neoplasm was diagnosed in almost 6% in a large cohort of LT candidates. Although almost a third of sinusitis patients were not treated accordingly, we did not observe any complicated sinusitis after LT. A more conservative approach to sinusitis may therefore be justified in LT candidates, especially in asymptomatic cases. At our institution, we aim to refer only those patients with specific ENT complaintsimage.This study aimed to evaluate the outcome of routine ear, nose, and throat screening in a large cohort of liver transplantation candidates. Note that, 6% were diagnosed with either sinusitis or a neoplasm. We did not observe any complicated sinusitis after transplantation. A more conservative approach may therefore be justified, especially in asymptomatic cases.imag
Evaluation of ear, nose, and throat-screening in liver transplantation candidates:A retrospective cohort study
Background:Patients with end-stage liver disease can be treated with a liver transplantation (LT). Before listing, candidates are subjected to a screening procedure according to the EASL Clinical Practice Guidelines for LT. In our hospital, this includes an ear, nose, and throat (ENT) examination, directed towards the identification of (asymptomatic) infections and head and neck malignancies.Methods:We retrospectively reviewed all ENT screening examinations in LT candidates from 2007 to 2022. The screening consisted of a visit to the ENT outpatient clinic combined with sinus radiography.Results:ENT screening was performed in 1099 patients. Sixty-one cases were identified, either diagnosed with an infection (n = 58, almost exclusively sinusitis) or a neoplasm (n = 3, of which two malignancies). With binary logistic regression, we could not identify significant risk factors for diagnosing sinusitis. 711 patients underwent LT. After LT, two patients developed a novel malignancy of the head and neck area, while 14 patients were diagnosed with sinusitis, two of the latter already showed opacification on sinus radiography during screening. Despite immunosuppressive drugs, no complicated sinusitis was observed.Conclusion:Sinusitis or a neoplasm was diagnosed in almost 6% in a large cohort of LT candidates. Although almost a third of sinusitis patients were not treated accordingly, we did not observe any complicated sinusitis after LT. A more conservative approach to sinusitis may therefore be justified in LT candidates, especially in asymptomatic cases. At our institution, we aim to refer only those patients with specific ENT complaintsimage.This study aimed to evaluate the outcome of routine ear, nose, and throat screening in a large cohort of liver transplantation candidates. Note that, 6% were diagnosed with either sinusitis or a neoplasm. We did not observe any complicated sinusitis after transplantation. A more conservative approach may therefore be justified, especially in asymptomatic cases.imag
Retrospective study in 1020 cases on the rate of surgical site infections after lacrimal surgery without prophylactic systemic antibiotics
Background/AimsData regarding the effectiveness of prophylactic systemic antibiotics (PSA) in lacrimal surgery is scarce. Therefore, we determined the postoperative surgical site infection (SSI) rate in lacrimal surgery without PSA.MethodsWe retrospectively analysed files of patients who underwent external (extDCR) or endoscopic endonasal dacryocystorhinostomy (endoDCR). We excluded patients with incomplete data (n = 68), acute a priori infection with the need for antibiotics (n = 15) and PSA post-operatively for other reasons (n = 28). Indications for surgery were canalicular stenosis (n = 51, 18.6% endoDCR vs n = 131, 19.5% extDCR), nasolacrimal duct obstruction (n = 118, 43.2% endoDCR vs n = 480, 64.3% extDCR) and mucocele/chronic dacryocystitis (n = 52, 19.0% endoDCR vs n = 187, 25.0% extDCR).ResultsIn this study, 1020 DCR surgeries were performed in 899 patients. Postoperative SSI was diagnosed in eight patients (0.8%); exclusively after extDCR (1.1% of all extDCR). No SSIs were found in endoDCR cases. The prevalence between SSI in extDCR versus endoDCR did not prove significant (n = 8/747 0.8% vs n = 0/273 0%, p = 0.13). All patients diagnosed with SSI were successfully treated with systemic oral antibiotics.ConclusionThe prevalence of SSI after DCR is low and was effectively treated with oral antibiotics. In our study, SSI occurred rarely after extDCR and was not observed after endoDCR. We conclude that lacrimal surgery is safe without the routine administration of PSA
The Importance of the Pathologist’s Role in Assessment of the Quality of the Mesorectum
Total mesorectal excision (TME) is considered standard of care for rectal cancer treatment. Failure to remove the mesorectal fat envelope entirely may explain part of observed local and distant recurrences. Several studies suggest quality of the mesorectum after TME surgery as determined by pathological evaluation may influence prognosis. We aimed to determine the prognostic value of the plane of surgery as well as factors influencing the likelihood of a high-quality specimen by reviewing the literature. A pooled meta-analysis of relevant outcome data was performed where appropriate. A muscularis propria resection plane was found to increase the risk of local recurrence (RR 2.72 [95Â % CI 1.36 to 5.44]) and overall recurrence (RR 2.00 [95Â % CI 1.17 to 3.42]) compared to an (intra)mesorectal plane. Plane of surgery is an important factor in rectal cancer treatment and the documentation by pathologists is essential for the improvement of TME quality and patient outcome
- …