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Evaluating e-Government services from a citizens' prespective: A reference process model
Evaluating and optimizing e-government services is imperative for governments especially due to the capacity of e-services to transform public administrations and assist the interactions of governments with citizens, businesses and other government agencies. Existing widely applied evaluation approaches neglect to incorporate citizensā satisfaction measures. Several citizen satisfaction models and indicators have been suggested in academia; however a reference process model that can assist practitioners to apply these performance measures is missing. In this paper we draw upon the evaluation approach proposed by the EU funded project CEES and propose a reference process model that captures re-usable practices for e-government evaluation from a citizensā perspective. The novelty of the proposed approach is that using DEA for evaluating the e-services the assessment results in suggestions for strategic improvement of the e-services.EU FP7 Marie Curie People Project āCEES - Citizen oriented Evaluation of E-Government Systemsā (reference IAPP-2008-230658
A Chaotic Quadratic Oscillator with Only Squared Terms: Multistability, Impulsive Control, and Circuit Design
Here, a chaotic quadratic oscillator with only squared terms is proposed, which shows various dynamics. The oscillator has eight equilibrium points, and none of them is stable. Various bifurcation diagrams of the oscillator are investigated, and its Lyapunov exponents (LEs) are discussed. The multistability of the oscillator is discussed by plotting bifurcation diagrams with various initiation methods. The basin of attraction of the oscillator is discussed in two planes. Impulsive control is applied to the oscillator to control its chaotic dynamics. Additionally, the circuit is implemented to reveal its feasibility
Constitutive basal and stimulated human small bowel contractility is enhanced in obesity
Small bowel contractility may be more prominent in obese subjects, such that there is enhanced nutrient absorption and hunger stimulation. However, there is little evidence to support this. This study examined in vitro small bowel contractility in obese patients versus non-obese patients
An External Parameter Independent Novel Cost Function for Evolving Bijective SubstitutionāBoxes
The property of nonlinearity has high importance for the design of strong substitution boxes. Therefore, the development of new techniques to produce substitution boxes with high values of nonlinearity is essential. Many research papers have shown that optimization algorithms are an efficient technique to obtain good solutions. However, there is no reference in the public literature showing that a heuristic method obtains optimal nonlinearity unless seeded with optimal initial solutions. Moreover, the majority of papers with the best nonlinearity reported for pseudo-random seeding of the algorithm(s) often achieve their results with the help of some cost function(s) over the WalshāHadamard spectrum of the substitution. In the sense, we proposed to present, in this paper, a novel external parameter independent cost function for evolving bijective s-boxes of high nonlinearity, which is highly correlated to this property. Several heuristic approaches including GaT (genetic and tree), LSA (local search algorithm), and the Hill Climbing algorithm have been investigated to assess the performance of evolved s-boxes. A performance comparison has been done to show the advantages of our new cost function, with respect to cost functions for s-boxes like Clarkās and Picekās cost functions
Gene silencing in tick cell lines using small interfering or long double-stranded RNA
Gene silencing by RNA interference (RNAi) is an important research tool in many areas of biology. To effectively harness the power of this technique in order to explore tick functional genomics and tick-microorganism interactions, optimised parameters for RNAi-mediated gene silencing in tick cells need to be established. Ten cell lines from four economically important ixodid tick genera (Amblyomma, Hyalomma, Ixodes and Rhipicephalus including the sub-species Boophilus) were used to examine key parameters including small interfering RNA (siRNA), double stranded RNA (dsRNA), transfection reagent and incubation time for silencing virus reporter and endogenous tick genes. Transfection reagents were essential for the uptake of siRNA whereas long dsRNA alone was taken up by most tick cell lines. Significant virus reporter protein knockdown was achieved using either siRNA or dsRNA in all the cell lines tested. Optimum conditions varied according to the cell line. Consistency between replicates and duration of incubation with dsRNA were addressed for two Ixodes scapularis cell lines; IDE8 supported more consistent and effective silencing of the endogenous gene subolesin than ISE6, and highly significant knockdown of the endogenous gene 2I1F6 in IDE8 cells was achieved within 48 h incubation with dsRNA. In summary, this study shows that gene silencing by RNAi in tick cell lines is generally more efficient with dsRNA than with siRNA but results vary between cell lines and optimal parameters need to be determined for each experimental system
Inhibition of Progenitor Dendritic Cell Maturation by Plasma from Patients with Peripartum Cardiomyopathy: Role in Pregnancy-associated Heart Disease
Dendritic cells (DCs) play dual roles in innate and adaptive immunity based
on their functional maturity, and both innate and adaptive immune responses have
been implicated in myocardial tissue remodeling associated with
cardiomyopathies. Peripartum cardiomyopathy (PPCM) is a rare disorder which
affects women within one month antepartum to five months postpartum. A high
occurrence of PPCM in central Haiti (1 in 300 live births) provided the unique
opportunity to study the relationship of immune activation and DC maturation
to the etiology of this disorder. Plasma samples from two groups (n = 12) of
age- and parity-matched Haitian women with or without evidence of PPCM were
tested for levels of biomarkers of cardiac tissue remodeling and immune
activation. Significantly elevated levels of GM-CSF, endothelin-1, proBNP and
CRP and decreased levels of TGF- were measured in PPCM subjects relative
to controls. Yet despite these findings, in vitro maturation of normal human
cord blood derived progenitor dendritic cells (CBDCs) was significantly
reduced (p < 0.001) in the presence of plasma from PPCM patients relative
to plasma from post-partum control subjects as determined by expression of
CD80, CD86, CD83, CCR7, MHC class II and the ability of these matured CBDCs
to induce allo-responses in PBMCs. These results represent the first findings
linking inhibition of DC maturation to the dysregulation of normal physiologic
cardiac
tissue remodeling during pregnancy and the pathogenesis of PPCM
Securing Digital Images through Simple Permutation-Substitution Mechanism in Cloud-Based Smart City Environment
Data security plays a significant role in data transfer in cloud-based smart cities. Chaotic maps are commonly used in designing modern cryptographic applications, in which one-dimensional (1D) chaotic systems are widely used due to their simple design and low computational complexity. However, 1D chaotic maps suffer from different kinds of attacks because of their chaotic discontinuous ranges and small key-space. To own the benefits of 1D chaotic maps and avoid their drawbacks, the cascading of two integrated 1D chaotic systems has been utilized. In this paper, we report an image cryptosystem for data transfer in cloud-based smart cities using the cascading of Logistic-Chebyshev and Logistic-Sine maps. Logistic-Sine map has been utilized to permute the plain image, and Logistic-Chebyshev map has been used to substitute the permuted image, while the cascading of both integrated maps has been utilized in performing XOR procedure on the substituted image. The security analyses of the suggested approach prove that the encryption mechanism has good efficiency as well as lower encryption time compared with other related algorithms
Quantitative analysis of cell composition and purity of human pancreatic islet preparations
Author Manuscript 2011 May 1.Despite improvements in outcomes for human islet transplantation, characterization of islet preparations remains poorly defined. This study used both light microscopy (LM) and electron microscopy (EM) to characterize 33 islet preparations used for clinical transplants. EM allowed an accurate identification and quantification of cell types with measured cell number fractions (meanĀ±s.e.m.) of 35.6Ā±2.1% Ī²-cells, 12.6Ā±1.0% non-Ī²-islet cells (48.3Ā±2.6% total islet cells), 22.7Ā±1.5% duct cells, and 25.3Ā±1.8% acinar cells. Of the islet cells, 73.6Ā±1.7% were Ī²-cells. For comparison with the literature, estimates of cell number fraction, cell volume, and extracellular volume were combined to convert number fraction data to volume fractions applicable to cells, islets, and the entire preparation. The mathematical framework for this conversion was developed. By volume, Ī²-cells were 86.5Ā±1.1% of the total islet cell volume and 61.2Ā±0.8% of intact islets (including the extracellular volume), which is similar to that of islets in the pancreas. Our estimates produced 1560Ā±20 cells in an islet equivalent (volume of 150-Ī¼m diameter sphere), of which 1140Ā±15 were Ī²-cells. To test whether LM analysis of the same tissue samples could provide reasonable estimates of purity of the islet preparations, volume fraction of the islet tissue was measured on thin sections available from 27 of the clinical preparations by point counting morphometrics. Islet purity (islet volume fraction) of individual preparations determined by LM and EM analyses correlated linearly with excellent agreement (R[superscript 2]=0.95). However, islet purity by conventional dithizone staining was substantially higher with a 20ā30% overestimation. Thus, both EM and LM provide accurate methods to determine the cell composition of human islet preparations and can help us understand many of the discrepancies of islet composition in the literature.National Institutes of Health (U.S.) (Grant RO1-DK063108)National Institutes of Health (U.S.) (Grant NCRR ICR U4Z RR 16606)Joslin Diabetes and Endocrinology Research Center (Grant DK36836)Diabetes Research & Wellness FoundationJuvenile Diabetes Research Foundation International (Islet Transplantation, Harvard Medical School
Genetic aberrations of c-myc and CCND1 in the development of invasive bladder cancer
Detrusor muscle invasive transitional cell carcinoma is associated with poor prognosis and is responsible for the majority of bladder cancer related deaths. Amplifications of c-myc and CCND1 are associated with detrusor-muscle-invasive transitional cell carcinoma, however, their precise role in driving disease progression is unclear. Fluorescence in situ hybridisation on archival tissue from 16 patients with primary diagnosis of ā©¾pT2 transitional cell carcinoma and 15 cases with primary pTa/pT1 disease subsequently progressing to detrusor-muscle-invasion was performed, in the latter group both pre and post muscle invasive events were studied. No patients presenting with ā©¾pT2 had amplification of c-myc, two out of 16 (12.5%) had CCND1 amplification. Of patients who developed ā©¾pT2, two out of 15 (13.3%) had amplification of c-myc, both in ā©¾pT2, five out of 15 (33.3%) had CCND1 amplification, two in pTa/pT1 tumours, three in ā©¾pT2 transitional cell carcinomas. In total, two out of 31 (6.5%) of patients' ā©¾pT2 TCCs were amplified for c-myc and six out of 31 (19%) were amplified for CCND1. Eighty-seven per cent (40 out of 46) of tumours were polysomic for chromosome 8 and 80% (37 out of 46) were polysomic for chromosome 11 and this reflected the high copy numbers of c-myc and CCND1 observed. In almost all cases an increase in c-myc/CCND1 copy number occurred prior to invasion and persisted in advanced disease. Amplification of CCND1 or alterations in c-myc/CCND1 early in bladder cancer may have clinical relevance in promoting and predicting progression to detrusor-muscle-invasive transitional cell carcinoma
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