Evaluation of social personalized adaptive E-Learning environments : end-user point of view

The use of adaptations, along with the social affordances of collaboration and networking, carries a great potential for improving e-learning experiences. However, the review of the previous work indicates current e-learning systems have only marginally explored the integration of social features and adaptation techniques. The overall aim of this research, therefore, is to address this gap by evaluating a system developed to foster social personalized adaptive e-learning experiences. We have developed our first prototype system, Topolor, based on the concepts of Adaptive Educational Hypermedia and Social E-Learning. We have also conducted an experimental case study for the evaluation of the prototype system from different perspectives. The results show a considerably high satisfaction of the end users. This paper reports the evaluation results from end user point of view, and generalizes our method to a component-based evaluation framework

The role of glomerular filtration and active tubular secretion in predicting renal clearance of drugs in children using population pharmacokinetic and physiology-based pharmacokinetic modeling approaches: unspinning the yarn

In this thesis population pharmacokinetic and physiologically-based pharmacokinetic (PBPK) approaches were applied to investigate the influence of glomerular filtration (GF) and active tubular secretion (ATS) on renal clearance in children. For this investigation, the contributions of passive (i.e. GF) and active (i.e. ATS) processes to renal clearance are considered. Both processes contribute to pediatric renal clearance and are expected to be influenced by developmental changes. Hence, the extent to which these developmental changes impact renal clearance is explored in pediatric populations using clinical data of existing drugs, and using a PBPK-based framework for hypothetical drugs with an array of different properties excreted by either GF or both GF and ATS. Pharmacolog

Systematic discovery of structural elements governing stability of mammalian messenger RNAs.

Decoding post-transcriptional regulatory programs in RNA is a critical step towards the larger goal of developing predictive dynamical models of cellular behaviour. Despite recent efforts, the vast landscape of RNA regulatory elements remains largely uncharacterized. A long-standing obstacle is the contribution of local RNA secondary structure to the definition of interaction partners in a variety of regulatory contexts, including--but not limited to--transcript stability, alternative splicing and localization. There are many documented instances where the presence of a structural regulatory element dictates alternative splicing patterns (for example, human cardiac troponin T) or affects other aspects of RNA biology. Thus, a full characterization of post-transcriptional regulatory programs requires capturing information provided by both local secondary structures and the underlying sequence. Here we present a computational framework based on context-free grammars and mutual information that systematically explores the immense space of small structural elements and reveals motifs that are significantly informative of genome-wide measurements of RNA behaviour. By applying this framework to genome-wide human mRNA stability data, we reveal eight highly significant elements with substantial structural information, for the strongest of which we show a major role in global mRNA regulation. Through biochemistry, mass spectrometry and in vivo binding studies, we identified human HNRPA2B1 (heterogeneous nuclear ribonucleoprotein A2/B1, also known as HNRNPA2B1) as the key regulator that binds this element and stabilizes a large number of its target genes. We created a global post-transcriptional regulatory map based on the identity of the discovered linear and structural cis-regulatory elements, their regulatory interactions and their target pathways. This approach could also be used to reveal the structural elements that modulate other aspects of RNA behaviour

Creep-Fatigue Crack Growth in Power Plant Components

In components operating at high temperature, the presence of defect, that may derive from manufacturing process or operating under critical conditions, could raise to creep-fatigue crack growth even at low loading conditions. Creep- fatigue experimental tests have been performed on P91 material, at 600 °C according to ASTM E2760-10 standard, with focus on the effects of the initial nominal stress intensity factor range, ranging between 16 and 22 MPa m 0.5, and the hold time, ranging between 0.1 and 10 hours. The results will be presented in the paper, together with their application for residual life prediction of a power plant cracked pipe, as case study

Cyclin D-Cdk4,6 Drives Cell-Cycle Progression via the Retinoblastoma Protein's C-Terminal Helix.

The cyclin-dependent kinases Cdk4 and Cdk6 form complexes with D-type cyclins to drive cell proliferation. A well-known target of cyclin D-Cdk4,6 is the retinoblastoma protein Rb, which inhibits cell-cycle progression until its inactivation by phosphorylation. However, the role of Rb phosphorylation by cyclin D-Cdk4,6 in cell-cycle progression is unclear because Rb can be phosphorylated by other cyclin-Cdks, and cyclin D-Cdk4,6 has other targets involved in cell division. Here, we show that cyclin D-Cdk4,6 docks one side of an alpha-helix in the Rb C terminus, which is not recognized by cyclins E, A, and B. This helix-based docking mechanism is shared by the p107 and p130 Rb-family members across metazoans. Mutation of the Rb C-terminal helix prevents its phosphorylation, promotes G1 arrest, and enhances Rb's tumor suppressive function. Our work conclusively demonstrates that the cyclin D-Rb interaction drives cell division and expands the diversity of known cyclin-based protein docking mechanisms

Lattice Boltzmann study on Kelvin-Helmholtz instability: the roles of velocity and density gradients

A two-dimensional lattice Boltzmann model with 19 discrete velocities for compressible Euler equations is proposed (D2V19-LBM). The fifth-order Weighted Essentially Non-Oscillatory (5th-WENO) finite difference scheme is employed to calculate the convection term of the lattice Boltzmann equation. The validity of the model is verified by comparing simulation results of the Sod shock tube with its corresponding analytical solutions. The velocity and density gradient effects on the Kelvin-Helmholtz instability (KHI) are investigated using the proposed model. Sharp density contours are obtained in our simulations. It is found that, the linear growth rate $\gamma$ for the KHI decreases with increasing the width of velocity transition layer ${D_{v}}$ but increases with increasing the width of density transition layer ${D_{\rho}}$. After the initial transient period and before the vortex has been well formed, the linear growth rates, $\gamma_v$ and $\gamma_{\rho}$, vary with ${D_{v}}$ and ${D_{\rho}}$ approximately in the following way, $\ln\gamma_{v}=a-bD_{v}$ and $\gamma_{\rho}=c+e\ln D_{\rho} ({D_{\rho}}<{D_{\rho}^{E}})$, where $a$, $b$, $c$ and $e$ are fitting parameters and ${D_{\rho}^{E}}$ is the effective interaction width of density transition layer. When ${D_{\rho}}>{D_{\rho}^{E}}$ the linear growth rate $\gamma_{\rho}$ does not vary significantly any more. One can use the hybrid effects of velocity and density transition layers to stabilize the KHI. Our numerical simulation results are in general agreement with the analytical results [L. F. Wang, \emph{et al.}, Phys. Plasma \textbf{17}, 042103 (2010)].Comment: Accepted for publication in PR

EFFICACY OF SOME TREATMENTS ON MONILINIA FRUCTIGENA (ADERH. & RUHL.) HONEY FUNGUS ATTACK ON APPLE

The researches were carried out in the experiments on the attack of Moniliniafructigena on apple in the Hartiesti location, Arges county. The evolution of the pathogen attack in the years 2015 and 2016 was monitored, in control variants and in variants treated with specific fungicides, included in a treatment scheme. The microscopic examination of the morphology of the pathogen corresponded to the fungus Moniliniafructigena. The biological material was Florina, Generos, Goldrush, Idared and Topaz varieties. In the conditions of year 2015, Moniliniafructigena's attack recorded values between 18.5% for Florina, 21% for Generos, 34% for Idared and 29.5% for Topaz. In the year 2016 the control variants of the fungus attack was 22% for the Florina variety and 36.5% for the Idared variety. The application of a treatment scheme that included specific products for the control like DithaneNeotec 0.2%, Topsin 0.07% and Switch 62.5WG 0.066% which had an efficacy of more than 66% in 2015 and 68% in the year 2016. In the varieties Florina and Topaz it have been calculated the highest efficacy values of over 70% during the experimentation period. Generos and Idared varieties recorded relatively close values of the efficacy of moniliosis treatments, ranging from 66.6% to 67.6% in 2015 and 69.4% respectively and 68.5% in the year 2016. The Florina variety was noted throughout the research period with the highest efficacy value E = 70.2% in 2015 and 77.25 in 2016