A methodology for estimating dog noise in an animal housing facility

A rectangular reverberation chamber was designed, constructed and calibrated for the experimental measurement of the sound power level (acoustic power) of a dog. Calibration of the chamber consisted of comparing the acoustic power measured for a random noise source in the chamber with that for the identical source in a free field environment. Data from dogs indicate that barking noise can be modeled as a square wave pattern with short duration and peak sound power levels in the 500 Hz octave band. A-weighted sound pressure levels of up to 114.7 dBA were absorbed, indicating a potential concern for both animals and man chronically exposed to such environments

Achievements and state of the art of hydrogen fuelled IC engines after twenty years of research at Ghent University

Paper presented at the 8th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Mauritius, 11-13 July, 2011.Hydrogen could be “the” fuel for the future, not only for fuel cells but certainly for internal combustion engines. The research on hydrogen started at Ghent University in 1990 with the adaptation of a Valmet diesel engine to hydrogen operation (atmospheric, carbureted version) to prove the capability of hydrogen as a fuel for IC engines. Since then several engines were modified for hydrogen use with the state of the art technologies (sequential injection, electronic management units). With European (Craft, Brite) and Belgian grants three buses demonstrated on several levels the application of hydrogen IC engines. At the moment the laboratory test proves an operation with a power output higher than the gasoline engine, with an equal efficiency of the diesel engine and with very low emissions (NOx less than 100 ppm). The interests of the research group of Ghent University was not only for the experimental work, but also the combustion process is simulated (GUEST code). The estimated formula of the laminar flame speed of hydrogen by Verhelst is worldwide used in other research studies. At the moment a doctoral study examines the heat transfer in hydrogen engines, which is so different from the already not very accurate heat transfer models in gasoline and diesel engines. In our laboratory tests, the hydrogen engine is ready for mass production (backfire safe, high power output, high efficiency, very low emissions). But storage on the vehicle recently and infrastructure of the fuel delivery are the bottle-necks for a real implementation of the hydrogen economy. From hydrogen, methanol can be produced on a sustainable way. Methanol is a liquid (no storage problem on het vehicle) and with minor modifications the same infrastructure can be used as for gasoline. Methanol has very good engine characteristics. Will methanol based on hydrogen be then “the” fuel of the future?mp201

Rise time evaluation of the heat flux microsensor (HFM) on a hot-air-gun test rig

Paper presented at the 8th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Mauritius, 11-13 July, 2011.Investigating the heat transfer inside internal combustion engines is key in the search for higher efficiency, higher power output and lower emissions. To understand the process and to validate model predictions, heat flux measurements inside an engine have to be conducted. In previous works, we have always used a commercially available thermopile to measure the heat transfer in a hydrogen combustion engine, but its large dimensions pose concerns about the sensor’s response time. Therefore, measurements have been done on a calibration rig with a hot air flow as heat source. This paper presents a comparison of the rise time of the thermopile with that of an alternative sensor developed for heat transfer measurements in gas turbines. The papers results in an increased confidence in the thermopile sensor, because its response time is at least as good as that of the alternative sensor. The results do show that the reproducibility of the test rig can be improved. Moreover, due to fluctuations in the heat flux level generated by the source, only the order of magnitude of the measured heat flux of two different experiments was comparable. Therefore, a new calibration rig will be developed to improve the reproducibility and to increase stability of the heat flux level of the heat source.mp201

‘We Learn Together’—Translanguaging within a Holistic Approach towards Multilingualism in Education

Within two multilingual education projects in the north of the Netherlands a holistic model for multilingualism in education is being tested. This is done through design-based interventions in which in- and pre-service teachers, teacher trainers and researchers co-develop and evaluate multilingual activities for different school types. Results show that through experimenting in a safe environment teachers gradually embraced their pupils’ multilingualism. This contradicts earlier findings on teachers strongly favouring monolingual instruction and viewing migrant languages as a deficit.<br/

Oestrogen receptor β and neoadjuvant therapy with tamoxifen: prediction of response and effects of treatment

In order to elucidate the relative importance of oestrogen receptor (ER)α, ERβ and an ERβ variant (ERβ2/βcx) in the response of breast cancers to tamoxifen, tumour levels of each receptor were assessed in 36 patients before and after 3 months of neoadjuvant treatment with tamoxifen (20 mg daily). All patients were postmenopausal women presenting with large ERα-positive breast cancers. Clinical response to treatment was assessed by tumour volume changes as determined from sequential ultrasounds and pathological response by comparison of the tumour morphology before and after treatment. Of 33 cases, 23 (70%) were classified as having a clinical response and 16 (48%) as having a response pathologically. All tumours stained positively for ERα and ERβ and 15 out of 33 (45%) for ERβ2/βcx. There were no significant differences in quantitative expression of any receptor between tumours that subsequently responded and that did not, whether response was assessed clinically or pathologically. Tamoxifen treatment was associated with a decrease in ERα, but an increase was the most frequent change (17 out of 33) in ERβ, and no consistent change was evident in staining of the ERβ2/βcx variant. In summary, ERβ1 and ERβ2/βcx variant protein are detected in ERα-positive breast tumours but their expression is not associated with a response to tamoxifen. Differential changes in ERα and ERβ were seen with treatment

Soy isoflavones and their relationship with microflora: beneficial effects on human health in equol producers

The bioavailability of soy isoflavones depends on the composition of the microflora for each subject. Bacteria act on different isoflavones with increased or reduced absorption and cause biotransformation of these compounds into metabolites with higher biological activity. S-equol is the most important metabolite and only 25–65 % of the population have the microflora that produces this compound. The presence of equol-producing bacteria in soy product consumers means that the consumption of such products for prolonged periods leads to lower cardiovascular risk, reduced incidence of prostate and breast cancer, and greater relief from symptoms related to the menopause such as hot flushes and osteoporosis

Motivated learning with digital learning tasks: what about autonomy and structure?

Article about Motivated learning with digital learning tasks: what about autonomy and structure

Expression of oestrogen receptors, ERα, ERβ, and ERβ variants, in endometrial cancers and evidence that prostaglandin F may play a role in regulating expression of ERα

<p>Abstract</p> <p>Background</p> <p>Endometrial cancer is the most common gynaecological malignancy; risk factors include exposure to oestrogens and high body mass index. Expression of enzymes involved in biosynthesis of oestrogens and prostaglandins (PG) is often higher in endometrial cancers when compared with levels detected in normal endometrium. Oestrogens bind one of two receptors (ERα and ERβ) encoded by separate genes. The full-length receptors function as ligand-activated transcription factors; splice variant isoforms of ERβ lacking a ligand-binding domain have also been described. PGs act in an autocrine or paracrine manner by binding to specific G-protein coupled receptors.</p> <p>Methods</p> <p>We compared expression of ERs, progesterone receptor (PR) and cyclooxygenase-2 (COX-2) in stage 1 endometrial adenocarcinomas graded as well (G1), moderately (G2) or poorly (G3) differentiated (n ≥ 10 each group) using qRTPCR, single and double immunohistochemistry. We used endometrial adenocarcinoma cell lines to investigate the impact of PGF2α on expression of ERs and PR.</p> <p>Results</p> <p>Full length ERβ (ERβ1) and two ERβ variants (ERβ2, ERβ5) were expressed in endometrial cancers regardless of grade and the proteins were immunolocalised to the nuclei of cells in both epithelial and stromal compartments. Immunoexpression of COX-2 was most intense in cells that were ERα^neg/low. Expression of PR in endometrial adenocarcinoma (Ishikawa) cell lines and tissues broadly paralleled that of ERα. Treatment of adenocarcinoma cells with PGF2α reduced expression of ERα but had no impact on ERβ1. Cells incubated with PGF2α were unable to increase expression of PR mRNA when they were incubated with E2.</p> <p>Conclusion</p> <p>We have demonstrated that ERβ5 protein is expressed in stage 1 endometrial adenocarcinomas. Expression of three ERβ variants, including the full-length protein is not grade-dependent and most cells in poorly differentiated cancers are ERβ^pos/ERα^neg. We found evidence of a link between COX-2, its product PGF2α, and expression of ERα and PR that sheds new light on the cross talk between steroid and PG signalling pathways in this disease.</p