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21.
Ella Kolkowska Fredrik Karlsson Karin Hedström 《The Journal of Strategic Information Systems》2017,26(1):39-57
Employees’ poor compliance with information security policies is a perennial problem. Current information security analysis methods do not allow information security managers to capture the rationalities behind employees’ compliance and non-compliance. To address this shortcoming, this design science research paper suggests: (a) a Value-Based Compliance analysis method and (b) a set of design principles for methods that analyse different rationalities for information security. Our empirical demonstration shows that the method supports a systematic analysis of why employees comply/do not comply with policies. Thus we provide managers with a tool to make them more knowledgeable about employees’ information security behaviours. 相似文献
22.
Regina Berg Johannes Straub Ella Schreiner Steffen Mader Frank Rominger Bernd F. Straub 《Advanced Synthesis \u0026amp; Catalysis》2012,354(18):3445-3450
The main feature of the herein presented class of molecularly defined catalysts for the copper‐catalyzed azide–alkyne cycloaddition reaction is the presence of two copper centres in one catalyst molecule. We report the facile three‐step synthesis of two representative bis‐NHC‐dicopper complexes as well as their catalytic performance in the azide–alkyne cycloaddition. A screening with one of these complexes has proved its wide applicability and excellent performance as homogeneous catalyst in various organic solvents and with different alkyne and azide substrates. 相似文献
23.
Wayne K. Dawson Amiu Shino Gota Kawai Ella Czarina Morishita 《International journal of molecular sciences》2021,22(18)
For the last 20 years, it has been common lore that the free energy of RNA duplexes formed from canonical Watson–Crick base pairs (bps) can be largely approximated with dinucleotide bp parameters and a few simple corrective constants that are duplex independent. Additionally, the standard benchmark set of duplexes used to generate the parameters were GC-rich in the shorter duplexes and AU-rich in the longer duplexes, and the length of the majority of the duplexes ranged between 6 and 8 bps. We were curious if other models would generate similar results and whether adding longer duplexes of 17 bps would affect the conclusions. We developed a gradient-descent fitting program for obtaining free-energy parameters—the changes in Gibbs free energy (ΔG), enthalpy (ΔH), and entropy (ΔS), and the melting temperature (Tm)—directly from the experimental melting curves. Using gradient descent and a genetic algorithm, the duplex melting results were combined with the standard benchmark data to obtain bp parameters. Both the standard (Turner) model and a new model that includes length-dependent terms were tested. Both models could fit the standard benchmark data; however, the new model could handle longer sequences better. We developed an updated strategy for fitting the duplex melting data. 相似文献
24.
25.
Marianna A. Zolotovskaia Max A. Kovalenko Victor S. Tkachev Alexander M. Simonov Maxim I. Sorokin Ella Kim Denis V. Kuzmin Betul Karademir-Yilmaz Anton A. Buzdin 《International journal of molecular sciences》2022,23(13)
In gliomas, expression of certain marker genes is strongly associated with survival and tumor type and often exceeds histological assessments. Using a human interactome model, we algorithmically reconstructed 7494 new-type molecular pathways that are centered each on an individual protein. Each single-gene expression and gene-centric pathway activation was tested as a survival and tumor grade biomarker in gliomas and their diagnostic subgroups (IDH mutant or wild type, IDH mutant with 1p/19q co-deletion, MGMT promoter methylated or unmethylated), including the three major molecular subtypes of glioblastoma (proneural, mesenchymal, classical). We used three datasets from The Cancer Genome Atlas and the Chinese Glioma Genome Atlas, which in total include 527 glioblastoma and 1097 low grade glioma profiles. We identified 2724 such gene and 2418 pathway survival biomarkers out of total 17,717 genes and 7494 pathways analyzed. We then assessed tumor grade and molecular subtype biomarkers and with the threshold of AUC > 0.7 identified 1322/982 gene biomarkers and 472/537 pathway biomarkers. This suggests roughly two times greater efficacy of the reconstructed pathway approach compared to gene biomarkers. Thus, we conclude that activation levels of algorithmically reconstructed gene-centric pathways are a potent class of new-generation diagnostic and prognostic biomarkers for gliomas. 相似文献
26.
Carrie Sheeler Juao-Guilherme Rosa Austin Ferro Brian McAdams Ella Borgenheimer Marija Cvetanovic 《International journal of molecular sciences》2020,21(23)
Over the past decade, research has unveiled the intimate relationship between neuroinflammation and neurodegeneration. Microglia and astrocytes react to brain insult by setting up a multimodal inflammatory state and act as the primary defenders and executioners of neuroinflammatory structural and functional changes. Microglia and astrocytes also play critical roles in the maintenance of normal brain function. This intricate balance of homeostatic and neuroinflammatory functions can influence the onset and the course of neurodegenerative diseases. The emergent role of the microglial-astrocytic axis in neurodegenerative disease presents many druggable targets that may have broad therapeutic benefits across neurodegenerative disease. Here, we provide a brief review of the basal function of both microglia and astrocytes, how they are changed in disease states, the significant differences between mouse and human glia, and use of human induced pluripotent stem cells derived from patients to study cell autonomous changes in human astrocytes and microglia. 相似文献
27.
This article reviews three previous factor analysis based studies of aggregate attitudes concerning the computer milieu and compares them with a recent one done by the authors; the four studies span almost twenty years. While providing a useful basis for making generalizations about current perceptions of the computer's role, the latest study also sought to determine whether there was a group of persons who were fearful or anxious about the computer, whose concerns were masked in studies of aggregate attitudes. By using an instrument that was evaluated by an expert in phobic behaviour, it was possible to identify a populationthat was significantly different from the general population in attitude toward computers. The value of the current study, then, is two-fold. It makes possible a retrospective view of aggregate perceptions of the general population about computers and also offers a glimpse of the attributes of those computer phobic or anxious persons who have not yet adapted to computer technology. 相似文献
28.
Ella Paton Gardner Linda B. Samuels Barry Render Richard L. Coffinberger 《Information Systems Management》1989,6(4):42-50
A recent survey shows that most people access computer resources without the benefit of clear standards of ethical and legal behavior in the MIS environment. This uninformed access leaves the organization - which is the legal custodian of computer data and software-susceptible to theft of resources and privacy and copyright violations as well as legal prosecution from law enforcement authorities. This article describes a survey of a cross section of MIS personnel and other system users in business, academia, and law enforcement and analyzes its results in the context of the current legal and ethical environment. It also suggests several remedies for reducing an organizations exposure to computer crime. 相似文献
29.
The aim was to present a novel automated approach for extracting the vasculature of retinal fundus images. The proposed vasculature extraction method on retinal fundus images consists of two phases: preprocessing phase and segmentation phase. In the first phase, brightness enhancement is applied for the retinal fundus images. For the vessel segmentation phase, a hybrid model of multilevel thresholding along with whale optimization algorithm (WOA) is performed. WOA is used to improve the segmentation accuracy through finding the \(n{-}1\) optimal n-level threshold on the fundus image. To evaluate the accuracy, sensitivity, specificity, accuracy, receiver operating characteristic (ROC) curve analysis measurements are used. The proposed approach achieved an overall accuracy of 97.8%, sensitivity of 88.9%, and specificity of 98.7% for the identification of retinal blood vessels by using a dataset that was collected from Bostan diagnostic center in Fayoum city. The area under the ROC curve reached a value of 0.967. Automated identification of retinal blood vessels based on whale algorithm seems highly successful through a comprehensive optimization process of operational parameters. 相似文献
30.
Ella Schoolaert Ronald Merckx Jana Becelaere Serge Rijssegem Richard Hoogenboom Karen De Clerck 《Advanced functional materials》2022,32(1):2106859
Colorimetric nanofibers provide visual, easy-to-interpret sensors for personal use as well as advanced applications. The potential of 2-n-butyl-2-oxazoline (B) and 2-ethyl-2-oxazoline (E) statistical copolymers as a universal, versatile support platform for nanofibrous halochromic sensor design is demonstrated. These polymers are electrospinnable from eco-friendly solvent systems, while wettability, moist adsorption capacity, and water-solubility of the membranes can be easily tuned by changing the B/E monomer ratio, ensuring wide applicability. The halochromic sensing functionality is introduced by incorporating the alizarin yellow R (AYR) chromophore, which is covalently modified with an ethyl ester-group or a short poly(2-n-butyl-2-oxazoline) chain, which is demonstrated to simultaneously prevent dye-leaching and allows tuning of the halochromic pH-sensing window. The colorimetric nanofibrous sensors reversibly respond toward aqueous solutions of different pH, (hydrochloric) acid and alkaline (ammonia) vapors, and several biogenic amines with detection limits as low as 5 ppb. Tunability of sensor responsivity, sensitivity, and pKa via manipulation of dye–polymer interactions, determined by support polymer structure and semi-crystallinity, as well as the chain length of the AYR-modified polymer, are discussed. Preliminary proof-of-principle studies indicate the potential of the developed sensors for sub-ppm biogenic amine vapor detection, which may serve as the basis for future applications in food packaging or breath analysis. 相似文献