Silicone Joint Dimensioning Calculation Methods

Historically, silicone joint dimensioning is calculated with a simplified equation implemented in various standards for structural glazing. This equation assumes homogeneous stress distribution along the sealant bite whilst high local stress peaks, structure deformation or material ageing are included in a global safety factor. Safeguards such as a maximum authorized deflection (1%) and aspect ratio to respect (between 1 and 3) have been given to ensure the validity of the used equations. However new trends in commercial buildings such as the use of large dimensions glass panes or stronger engineering performance requirements such as high windloads above 5000Pa lead to the non-respect of these guidelines and the impossibility to use the simplified equation. An improved mathematical relationship making a direct correspondence between a joint included in a façade system and the behavior of a test piece was recently proposed by the authors. The goal of this article is to further validate the proposed relationship by confronting predictions with physical measurements on various test samples and the results from FEA modeling. The domain of validity of the simplified equation and the improved equation will be developed

Dimensioning Silicone Joints Used in Bomb Blast Resistant Facade Systems

In the design of blast resistant glazing systems, gluing the laminate glass to the window frame with a structural adhesive is an attractive option to maintain it attached to the frame while, because the large deflection of the broken laminate, it could potentially escape from a mechanical fixing. Actually, it does not exist a simple method that provides guidelines to the facade maker to design a joint that will resist to a blast. The complexity to develop such a method is due to 1) the blast load is time dependent and the phase shift between the external load and the natural mode of vibration of the pane must be included in the model 2) modeling the deformation of a laminated glass after breakage of glass plies is complex. The intend of this study is not to propose the most accurate description of both the laminate and the joint deformation under a blast load but to identify which assumptions could be possibly made to simplify the problem and make possible the derivation of a simplified joint dimensioning method

Au large de Port-Vendres – La Mirande, Port-Vendres 5

Les fouilles de cette épave se sont achevées en 1992. L’inventaire des cent soixante-sept amphores individualisées se répartit de la manière suivante : cent quarante-huit Pascual 1 issues de trois productions différentes ; onze Dr. 2/4 ; huit autres amphores (trois Halt. 70, deux Dr. 7/11, une Dr. 9, deux amphores à fond plat). Les amphores n’ont pas été rattachées à des centres de production particuliers. Les deux timbres circulaires et les quatorze graffiti sur Pascual 1 n’ont pas trouvé de..

Adjuvant therapeutic potential of tonabersat in the standard treatment of glioblastoma : a preclinical F98 glioblastoma rat model study

Purpose Even with an optimal treatment protocol, the median survival of glioblastoma (GB) patients is only 12-15 months. Hence, there is need for novel effective therapies that improve survival outcomes. Recent evidence suggests an important role for connexin (Cx) proteins (especially Cx43) in the microenvironment of malignant glioma. Cx43-mediated gap junctional communication has been observed between tumor cells, between astrocytes and between tumor cells and astrocytes. Therefore, gap junction directed therapy using a pharmacological suppressor or modulator, such as tonabersat, could be a promising target in the treatment of GB. In this preclinical study, we evaluated the possible therapeutic potential of tonabersat in the F98 model. Procedures Female Fischer rats were inoculated with +/- 25.000 F98 tumor cells in the right frontal lobe. Eight days post-inoculation contrast-enhanced T1-weighted (CE-T1w) magnetic resonance (MR) images were acquired to confirm tumor growth in the brain. After tumor confirmation, rats were randomized into a Control Group, a Connexin Modulation Group (CM), a Standard Medical Treatment Group (ST), and a Standard Medical Treatment with adjuvant Connexin Modulation Group (STCM). To evaluate therapy response, T2-weighted (T2w) and CE-T1w sequences were acquired at several time points. Tumor volume analysis was performed on CE-T1w images and statistical analysis was performed using a linear mixed model. Results Significant differences in estimated geometric mean tumor volumes were found between the ST Group and the Control Group and also between the STCM Group and the Control Group. In addition, significant differences in estimated geometric mean tumor volumes between the ST Group and the STCM Group were demonstrated. No significant differences in estimated geometric mean tumor volumes were found between the Control Group and the CM Group. Conclusion Our results demonstrate a therapeutic potential of tonabersat for the treatment of GB when used in combination with radiotherapy and temozolomide chemotherapy

Near infra-red spectroscopy of the asteroid 21 Lutetia. II. Rotationally resolved spectroscopy of the surface

Reproduced with permission. Copyright ESO. Article published by EDP Sciences and available at http://www.aanda.orgInternational audienceAims. In the framework of the ground-based science campaign dedicated to the encounter with the Rosetta spacecraft, the mineralogy of the asteroid (21) Lutetia was investigated. Methods. Near-infrared (NIR) spectra of the asteroid in the 0.8−2.5 μm spectral range were obtained with SpeX/IRTF in remote observing mode from Meudon, France in March and April 2006. We analysed these data together with previously acquired spectra - March 2003, August 2004. I-band relative photometric data obtained on 20 January 2006 using the 105 cm telescope from Pic du Midi, France has been used to build the ephemeris for physical observations. A χ2 test using meteorite spectra from the RELAB database was performed in order to find the best fit of complete visible + infrared (VNIR) spectra of Lutetia. Results. The new spectra reveal no absorption features. We find a clear spectral variation (slope), and a good correspondence between spectral variations and rotational phase. Two of the most different spectra correspond to two opposite sides of the asteroid (sub-Earth longitude difference around 180◦). For the neutral spectra a carbonaceous chondrite spectrum yields the best fit, while for those with a slightly positive slope the enstatitic chondrite spectra are the best analog. Based on the chosen subset of the meteorite samples, our analysis suggests a primitive, chondritic nature for (21) Lutetia. Differences in spectra are interpreted in terms of the coexistence of several lithologies on the surface where the aqueous alteration played an important role

Accompagner les étudiants bacheliers bioingénieurs dans le développement de leurs compétences transversales

Cet article propose de décrire la conception, le déroulé et l’évaluation de quatre modules de formation aux compétences transversales instaurés dans le cadre d’une réforme du programme de bachelier dans la Faculté des bioingénieurs de l’UCLouvain en réponse à deux enjeux facultaires : 1) intégrer les disciplines dans un contexte plus appliqué et 2) développer les compétences transversales des futurs bioingénieurs. Le scénario des modules prenait pour point d’ancrage la connaissance de soi et la conscience des différences interpersonnelles et visait un développement progressif des compétences de collaboration, d’organisation et de communication, en articulation directe à la réalisation d’un projet. Quarante-quatre équipes d’étudiants ont pris part au dispositif. Celui-ci a fait l’objet d’une évaluation quantitative (enquête) et qualitative (focus group). Les résultats intègrent des mesures de l’efficacité du groupe et des émotions vécues

Kinetic modeling and graphical analysis of 18F-fluoromethylcholine (FCho), 18F-fluoroethyltyrosine (FET) and 18F-fluorodeoxyglucose (FDG) PET for the discrimination between high-grade glioma and radiation necrosis in rats

Background : Discrimination between glioblastoma (GB) and radiation necrosis (RN) post-irradiation remains challenging but has a large impact on further treatment and prognosis. In this study, the uptake mechanisms of 18F-fluorodeoxyglucose (18F-FDG), 18F-fluoroethyltyrosine (18F-FET) and 18F-fluoromethylcholine (18F-FCho) positron emission tomography (PET) tracers were investigated in a F98 GB and RN rat model applying kinetic modeling (KM) and graphical analysis (GA) to clarify our previous results. Methods : Dynamic 18F-FDG (GB n = 6 and RN n = 5), 18F-FET (GB n = 5 and RN n = 5) and 18F-FCho PET (GB n = 5 and RN n = 5) were acquired with continuous arterial blood sampling. Arterial input function (AIF) corrections, KM and GA were performed. Results : The influx rate (Ki) of 18F-FDG uptake described by a 2-compartmental model (CM) or using Patlak GA, showed more trapping (k(3)) in GB (0.07 min(-1)) compared to RN (0.04 min(-1)) (p = 0.017). K-1 of 18F-FET was significantly higher in GB (0.06 ml/ccm/min) compared to RN (0.02 ml/ccm/min), quantified using a 1-CM and Logan GA (p = 0.036). 18F-FCho was rapidly oxidized complicating data interpretation. Using a 1-CM and Logan GA no clear differences were found to discriminate GB from RN. Conclusions : Based on our results we concluded that using KM and GA both 18F-FDG and 18F-FET were able to discriminate GB from RN. Using a 2-CM model more trapping of 18F-FDG was found in GB compared to RN. Secondly, the influx of 18F-FET was higher in GB compared to RN using a 1-CM model. Important correlations were found between SUV and kinetic or graphical measures for 18F-FDG and 18F-FET. 18F-FCho PET did not allow discrimination between GB and RN

Synergy between intraperitoneal aerosolization (PIPAC) and cancer nanomedicine : cisplatin-loaded polyarginine-hyaluronic acid nanocarriers efficiently eradicate peritoneal metastasis of advanced human ovarian cancer

Intra-abdominal dissemination of peritoneal nodules, a condition known as peritoneal carcinomatosis (PC), is typically diagnosed in ovarian cancer patients at the advanced stages. The current treatment of PC consists of perioperative systemic chemotherapy and cytoreductive surgery, followed by intra-abdominal flushing with solutions of chemotherapeutics such as cisplatin and oxaliplatin. In this study, we developed cisplatin-loaded polyarginine-hyaluronic acid nanoscale particles (Cis-pARG-HA NPs) with high colloidal stability, marked drug loading efficiency, unimpaired biological activity, and tumor-targeting ability. Injected Cis-pARG-HA NPs showed enhanced antitumor activity in a rat model of PC, compared to injection of the free cisplatin drug. The activity of Cis-pARG-HA NPs could even be further improved when administered by an intra-abdominal aerosol therapy, referred to as pressurized intraperitoneal aerosol chemotherapy (PIPAC). PIPAC is hypothesized to ensure a more homogeneous drug distribution together with a deeper drug penetration into peritoneal tumor nodules within the abdominal cavity. Using fluorescent pARG-HA NPs, this enhanced nanoparticle deposit on tumors could indeed be observed in regions opposite the aerosolization nozzle. Therefore, this study demonstrates that nanoparticles carrying chemotherapeutics can be synergistically combined with the PIPAC technique for IP therapy of disseminated advanced ovarian tumors, while this synergistic effect was not observed for the administration of free cisplatin

Technical feasibility of [18F]FET and [18F]FAZA PET guided radiotherapy in a F98 glioblastoma rat model

Background: Glioblastoma (GB) is the most common primary malignant brain tumor. Standard medical treatment consists of a maximal safe surgical resection, subsequently radiation therapy (RT) and chemotherapy with temozolomide (TMZ). An accurate definition of the tumor volume is of utmost importance for guiding RT. In this project we investigated the feasibility and treatment response of subvolume boosting to a PET-defined tumor part. Method: F98 GB cells inoculated in the rat brain were imaged using T2- and contrast-enhanced T1-weighted (T1w) MRI. A dose of 20 Gy (5 x 5 mm(2)) was delivered to the target volume delineated based on T1w MRI for three treatment groups. Two of those treatment groups received an additional radiation boost of 5 Gy (1 x 1 mm(2)) delivered to the region either with maximum [F-18]FET or [F-18]FAZA PET tracer uptake, respectively. All therapy groups received intraperitoneal (IP) injections of TMZ. Finally, a control group received no RT and only control IP injections. The average, minimum and maximum dose, as well as the D-90-, D-50- and D-2- values were calculated for nine rats using both RT plans. To evaluate response to therapy, follow-up tumor volumes were delineated based on T1w MRI. Results: When comparing the dose volume histograms, a significant difference was found exclusively between the D-2-values. A significant difference in tumor growth was only found between active therapy and sham therapy respectively, while no significant differences were found when comparing the three treatment groups. Conclusion: In this study we showed the feasibility of PET guided subvolume boosting of F98 glioblastoma in rats. No evidence was found for a beneficial effect regarding tumor response. However, improvements for dose targeting in rodents and studies investigating new targeted drugs for GB treatment are mandatory

No selection on immunological markers in response to a highly virulent pathogen in an Arctic breeding bird

In natural populations, epidemics provide opportunities to look for intense natural selection on genes coding for life history and immune or other physiological traits. If the populations being considered are of management or conservation concern, then identifying the traits under selection (or ‘markers’) might provide insights into possible intervention strategies during epidemics. We assessed potential for selection on multiple immune and life history traits of Arctic breeding common eiders (Somateria mollissima) during annual avian cholera outbreaks (summers of 2006, 2007 & 2008). We measured prelaying body condition, immune traits, and subsequent reproductive investment (i.e., clutch size) and survival of female common eiders and whether they were infected with Pasteurella multocida, the causative agent of avian cholera. We found no clear and consistent evidence of directional selection on immune traits; however, infected birds had higher levels of haptoglobin than uninfected birds. Also, females that laid larger clutches had slightly lower immune responses during the prelaying period reflecting possible downregulation of the immune system to support higher costs of reproduction. This supports a recent study indicating that birds investing in larger clutches were more likely to die from avian cholera and points to a possible management option to maximize female survival during outbreaks