Effects of content and language integrated learning in Europe: A systematic review of longitudinal experimental studies

Contains fulltext : 209181.pdf (publisher's version ) (Open Access)Content and language integrated learning (CLIL), an educational approach in which subject matter and a foreign language - predominantly English - are taught and learnt side by side, has developed into a very popular educational innovation in most European countries. A host of research studies have shown its benefits, and discuss favourable effects especially with respect to L2 gains. However, critical voices have underscored the fact that CLIL attracts or selects mainly high-achieving learners. Hence, the question arises whether it is justified to attribute improved L2 performance mainly to the CLIL intervention, or to favourable learner characteristics. Several reviews of literature were published in the past, but due to a lack of longitudinal findings no conclusive evidence about the added value of CLIL in the process of L2 learning could be produced. The present review aims to fill this void and has undertaken a search of two decades of longitudinal studies into the effects of CLIL on various linguistic skills in the field of English as a foreign language. The findings indicate that robust studies were undertaken in only a limited number of European countries, and that only a few of them were large scale. Yet, the conclusions provide clear indications regarding the contexts in which CLIL leads to significantly better L2 results.24 p

The application of homogeneous reactor models to examine the conversion of Polycyclic Aromatic Hydrocarbons in biomass derived fuel gases

The removal of tar from biomass derived fuel gases is considered to be a bottleneck in the widespread application of biomass gasification. Tar is made up of Polycyclic Aromatic Hydrocarbons (PAHs) consisting of fused aromatic rings. Past research has proven the possibility to remove the PAH species naphthalene from producer gas at high temperature by means of introducing a limited amount of oxidizer. This process, which also can be regarded as partialcombustion, is not yet fully understood. By conducting a fundamental study of the mechanisms involved it will be possible to optimize the process conditions and the reactor geometry. In the work presented here it is examined if partial combustion can be described by homogeneous reactors. The PAH species representing the tar content of the producer gas is naphthalene (in correspondence with the executed experiments). Chemical equilibrium calculations indicate that, if time scales approach infinity, it is possible to convert naphthalene to lighter hydrocarbons at smallvalues of the equivalence ratio, lambda. For lambda <0.2, soot is produced. The influence of chemical kinetics is examined with Perfectly Stirred Reactor (PSR) calculations. The results reveal that the time scales involved in the conversion of naphthalene at small values of the equivalence ratio (0 <lambda <0.2) are considerate. This leads to the conclusion that the process of tar cracking by partial combustion cannot be described by homogeneous reactors alone. The experimental results are not fully explained by the presented results. This indicates that heterogeneous effects should be taken into account. This requires full 2D simulations in which molecular transport is included

Processing and mechanical properties of magnesium-lithium composites containing steel fibers

Deformation-processed metal-metal composites (DMMC) of Mg-Li alloys containing steel reinforcing fibers were prepared by infiltrating a preform of steel wool with the molten matrix. The Li content was varied to control the crystal structure of the matrix; Mg-4 wt pct Li is hexagonal close packed (hcp), while Mg-12 wt pct Li is body-centered cubic (bcc). The low carbon steel used as the reinforcing fiber is essentially bcc. The hcp/bcc and bcc/bcc composites were subsequently deformed by rolling and by extrusion/swaging and mechanically tested to relate the tensile strength of the composites to true deformation strain. The hcp/bcc composites had limited formability at temperatures up to 400 °C, while the bcc/bcc composites had excellent formability during sheet rolling at room temperature but limited formability during swaging at room temperature. The tensile strengths of the hcp/bcc composite rod and the bcc/bcc composite sheet and rod increased moderately with deformation, though less than predicted from rule-of-mixtures (ROM) calculations. This article presents the experimental data for these DMMC materials and comments on the possible effect of texture development in the matrix and fiber phases on the deformation characteristics of the composite material

Macrosegregation Caused by Thermosolutal Convection During Directional Solidification of Pb-Sb Alloys

Pb-2.2 and 5.8 wt pet Sb alloys were directionally solidified with a positive thermal gradient of 140 K cm(-1) at growth speeds ranging from 0.8 to 30 mu m s(-1), and then quenched to retain the mushy-zone morphology. Chemical analysis along the length of the directionally solidified portion and in the quenched melt ahead of the dendritic array showed extensive longitudinal macrosegregation, Cellular morphologies growing at smaller growth speeds are associated with larger amounts of macrosegregation as compared with the dendrites growing at higher growth speeds. Convection is caused, mainly, by the density inversion in the overlying melt ahead of the cellular/dendritic array because of the antimony enrichment at the array tip. Mixing of the interdendritic and bulk melt during directional solidification is responsible for the observed longitudinal macrosegregation

Implementatie Kaderrichtlijn water op melkveebedrijven

As an alternative to application of more generic measures, in 'Landbouw Centraal' a method is tested to improve water quality by dairy farmers. Reduction of emmissions of at least 10% (N) to 20% (P2O5) towards ground- and surface waters should be possible, without harming the economical farm result

The Effect of Convection on Disorder in Primary Cellular and Dendritic Arrays

Directional solidification studies have been carried out to characterize the spatial disorder in the arrays of cells and dendrites. Different factors that cause array disorder are investigated experimentally and analyzed numerically. In addition to the disorder resulting from the fundamental selection of a range of primary spacings under given experimental conditions, a significant variation in primary spacings is shown to occur in bulk samples due to convection effects, especially at low growth velocities. The effect of convection on array disorder is examined through directional solidification studies in two different alloy systems, Pb-Sn and Al-Cu. A detailed analysis of the spacing distribution is carried out, which shows that the disorder in the spacing distribution is greater in the Al-Cu system than in Pb-Sn system. Numerical models are developed which show that fluid motion can occur in both these systems due to the negative axial density gradient or due the radial temperature gradient which is always present in Bridgman growth. The modes of convection have been found to be significantly different in these systems, due to the solute being heavier than the solvent in the Al-Cu system and lighter than it in the Pb-Sn system. The results of the model have been shown to explain experimental observations of higher disorder and greater solute segregation in a weakly convective Al-Cu system than those in a highly convective Pb-Sn system

Diagnostic exome sequencing in 266 Dutch patients with visual impairment

Inherited eye disorders have a large clinical and genetic heterogeneity, which makes genetic diagnosis cumbersome. An exome-sequencing approach was developed in which data analysis was divided into two steps: the vision gene panel and exome analysis. In the vision gene panel analysis, variants in genes known to cause inherited eye disorders were assessed for pathogenicity. If no causative variants were detected and when the patient consented, the entire exome data was analyzed. A total of 266 Dutch patients with different types of inherited eye disorders, including inherited retinal dystrophies, cataract, developmental eye disorders and optic atrophy, were investigated. In the vision gene panel analysis (likely), causative variants were detected in 49% and in the exome analysis in an additional 2% of the patients. The highest detection rate of (likely) causative variants was in patients with inherited retinal dystrophies, for instance a yield of 63% in patients with retinitis pigmentosa. In patients with developmental eye defects, cataract and optic atrophy, the detection rate was 50, 33 and 17%, respectively. An exome-sequencing approach enables a genetic diagnosis in patients with different types of inherited eye disorders using one test. The exome approach has the same detection rate as targeted panel sequencing tests, but offers a number of advantages. For instance, the vision gene panel can be frequently and easily updated with additional (novel) eye disorder genes. Determination of the genetic diagnosis improved the clinical diagnosis, regarding the assessment of the inheritance pattern as well as future disease perspective

The PHENIX Experiment at RHIC

The physics emphases of the PHENIX collaboration and the design and current status of the PHENIX detector are discussed. The plan of the collaboration for making the most effective use of the available luminosity in the first years of RHIC operation is also presented.Comment: 5 pages, 1 figure. Further details of the PHENIX physics program available at http://www.rhic.bnl.gov/phenix