A Soft Systems Methodology (SSM) Based Framework for Evaluating Managed Learning Environments

Managed Learning Environments (MLEs) in higher education institutions (HEIs) are relatively new to the arena of higher education, even though there are over 90% of institutions in the higher and further education sector who are currently engaged in some kind of MLE development activity (University of Brighton 2003). However, when it comes to the task of assessing the performance of an MLE there are no universally recognisable frameworks for evaluating MLEs in HEIs currently discussed within the literature. The paper advances a general systemic framework for evaluating MLEs based on Checkland’s SSM and reports on the first stages of our attempt to evaluate the MLE at Manchester Metropolitan University involving the team developing the system and the stakeholders concerned. Two of three iterations of this research have been completed and, whilst outside the scope of this paper, have found that SSM has coped with the criteria demanded of the evaluation framework within its context. After completing a stakeholder analysis, the criteria for evaluating an MLE, based on the stakeholders’ requirements, emerged. These iterations have tentatively concluded that by contextualising SSM to the evaluation requirements of an MLE in a UK HEI, the measures of performance suggested by SSM need to be adjusted. The final iteration will check this outcome.     

First record of diamondback moth ( Lepidoptera: Plutellidae ) from interior Alaska

The diamondback moth ( Plutella xylostella [L.]), is one of the most economically important pests of cruciferous plants throughout the world, causing economically significant damage in broccoli, cabbage, canola, collards, and mustard. In Canada, P. xylostella is an important economic pest of canola ( Brassica napus L. and Brassica rapa L.). In North America, the diamondback moth has been collected as far north as Edmonton, Alberta, Canada. Despite its wide distribution and presence at economically damaging levels in Canada, there have been no published reports of P. xylostella from Alaska. This note documents the 1st collection of this pest species in interior Alaska. With continued moderation of the climate due to global climate change, this species has the potential to become an increasingly important agricultural pest in the state.     

GSK3 and β-catenin determines functional expression of sodium channels at the axon initial segment

Neuronal action potentials are generated through voltage-gated sodium channels, which are tethered by ankyrinG at the membrane of the axon initial segment (AIS). Despite the importance of the AIS in the control of neuronal excitability, the cellular and molecular mechanisms regulating sodium channel expression at the AIS remain elusive. Our results show that GSK3α/β and β-catenin phosphorylated by GSK3 (S33/37/T41) are localized at the AIS and are new components of this essential neuronal domain. Pharmacological inhibition of GSK3 or β-catenin knockdown with shRNAs decreased the levels of phosphorylated-β-catenin, ankyrinG, and voltage-gated sodium channels at the AIS, both “in vitro” and “in vivo”, therefore diminishing neuronal excitability as evaluated via sodium current amplitude and action potential number. Thus, our results suggest a mechanism for the modulation of neuronal excitability through the control of sodium channel density by GSK3 and β-catenin at the AIS.     

无线电频率回路的噪音分析

在高速通信和信号处理应用中，来自设备的随机电噪音对系统的差错率和信噪比会产生很大的影响，因此，在设计阶段，预测无线电频率系统中的噪音是非常重要的，本书论述无线电频率回路的噪音模拟技术。     

Identification of the gene (BBS1) most commonly involved in Bardet-Biedl syndrome,a complex human obesity syndrome

Bardet-Biedl syndrome (BBS, OMIM 209900) is a genetic disorder with the primary features of obesity, pigmentary retinopathy, polydactyly, renal malformations, mental retardation and hypogenitalism. Individuals with BBS are also at increased risk for diabetes mellitus, hypertension and congenital heart disease. What was once thought to be a homogeneous autosomal recessive disorder is now known to map to at least six loci: 11q13 (BBS1), 16q21 (BBS2), 3p13 p12 (BBS3), 15q22.3 q23 (BBS4), 2q31 (BBS5) and 20p12 (BBS6). There has been considerable interest in identifying the genes that underlie BBS, because some components of the phenotype are common. Cases of BBS mapping ro BBS6 are caused by mutations in MKKS; mutations in this gene also cause McKusick-Kaufman syndrome (hydrometrocolpos, post-axial polydactyly and congenital heart defects). In addition, we recently used positional cloning to identify the genes underlying BBS2 (ref. 16) and BBS4 (ref. 17). The BBS6 protein has similarity to a Thermoplasma acidophilum chaperonin, whereas BBS2 and BBS4 have no significant similarity to chaperonins. It has recently been suggested that three mutated alleles (two at one locus, and a third at a second locus) may be required for manifestation of BBS (triallelic inheritance). Here we report the identification of the gene BBS1 and show that a missense mutation of this gene is a frequent cause of BBS. In addition, we provide data showing that this common mutation is not involved in triallelic inheritance.     

Modelling the daily banknotes in circulation in the context of the liquidity management of the European Central Bank

The main focus of this paper is to model the daily series of banknotes in circulation. The series of banknotes in circulation displays very marked seasonal patterns. To the best of our knowledge the empirical performance of two competing approaches to model seasonality in daily time series, namely the ARIMA‐based approach and the Structural Time Series approach, has never been put to the test. The application presented in this paper provides valid intuition on the merits of each approach. The forecasting performance of the models is also assessed in the context of their impact on the liquidity management of the Eurosystem. Copyright © 2008 John Wiley & Sons, Ltd.     

Loss of acetylation at Lys16 and trimethylation at Lys20 of histone H4 is a common hallmark of human cancer

CpG island hypermethylation and global genomic hypomethylation are common epigenetic features of cancer cells. Less attention has been focused on histone modifications in cancer cells. We characterized post-translational modifications to histone H4 in a comprehensive panel of normal tissues, cancer cell lines and primary tumors. Using immunodetection, high-performance capillary electrophoresis and mass spectrometry, we found that cancer cells had a loss of monoacetylated and trimethylated forms of histone H4. These changes appeared early and accumulated during the tumorigenic process, as we showed in a mouse model of multistage skin carcinogenesis. The losses occurred predominantly at the acetylated Lys16 and trimethylated Lys20 residues of histone H4 and were associated with the hypomethylation of DNA repetitive sequences, a well-known characteristic of cancer cells. Our data suggest that the global loss of monoacetylation and trimethylation of histone H4 is a common hallmark of human tumor cells.     

Caenorhabditis elegans ABL-1 antagonizes p53-mediated germline apoptosis after ionizing irradiation

c-Abl, a conserved nonreceptor tyrosine kinase, integrates genotoxic stress responses, acting as a transducer of both pro- and antiapoptotic effector pathways. Nuclear c-Abl seems to interact with the p53 homolog p73 to elicit apoptosis. Although several observations suggest that cytoplasmic localization of c-Abl is required for antiapoptotic function, the signals that mediate its antiapoptotic effect are largely unknown. Here we show that worms carrying an abl-1 deletion allele, abl-1(ok171), are specifically hypersensitive to radiation-induced apoptosis in the Caenorhabditis elegans germ line. Our findings delineate an apoptotic pathway antagonized by ABL-1, which requires sequentially the cell cycle checkpoint genes clk-2, hus-1 and mrt-2; the C. elegans p53 homolog, cep-1; and the genes encoding the components of the conserved apoptotic machinery, ced-3, ced-9 and egl-1. ABL-1 does not antagonize germline apoptosis induced by the DNA-alkylating agent ethylnitrosourea. Furthermore, worms treated with the c-Abl inhibitor STI-571 (Gleevec; used in human cancer therapy), two newly synthesized STI-571 variants or PD166326 had a phenotype similar to that generated by abl-1(ok171). These studies indicate that ABL-1 distinguishes proapoptotic signals triggered by two different DNA-damaging agents and suggest that C. elegans might provide tissue models for development of anticancer drugs.