Measuring for Knowledge: A Data-Driven Research Approach for eGovernment

As ICT provide a lot of possibilities, high expectancies exist towards the electronic public service provision. All governments are increasingly establishing their e-strategies. However, eGovernment still faces many challenges as it continues to develop. The current status of electronic services delivery opens up a lot of questions, both for practitioners and researchers. Therefore, further progress of eGovernment needs a profound knowledge base. eGovernment policy has focused several years on bringing online public services and on benchmarking their availability and sophistication. Simultaneously, eGovernment measurement and monitoring activities are often based on the so-called supply-side benchmarking. Although this is important knowledge, it is under criticism because it lacks a user-centric viewpoint of eGovernment development. This article presents and discusses a bottom-up and data-driven approach about how research can help to manage (user-centric) eGovernment strategies. Based on statistical testing (techniques of structural equation modeling, SEM) of large-scale sample data from the Belgian government, the authors have investigated which relations do exist between contextual variables and the availability and/or satisfaction of electronic public services. By doing this, this manuscript presents an illustration of a data-driven approach in eGovernment monitoring and it explains how this can support and enrich the management and evaluation of eGovernment policy

Gigahertz repetition rate thermionic electron gun concept

We present a novel concept for the generation of gigahertz repetition rate high brightness electron bunches. A custom design 100 kV thermionic gun provides a continuous electron beam, with the current determined by the filament size and temperature. A 1 GHz rectangular RF cavity deflects the beam across a knife-edge, creating a pulsed beam. Adding a higher harmonic mode to this cavity results in a flattened magnetic field profile which increases the duty cycle to 30%. Finally, a compression cavity induces a negative longitudinal velocity-time chirp in a bunch, initiating ballistic compression. Adding a higher harmonic mode to this cavity increases the linearity of this chirp and thus decreases the final bunch length. Charged particle simulations show that with a 0.15 mm radius LaB6 filament held at 1760 K, this method can create 279 fs, 3.0 pC electron bunches with a radial rms core emittance of 0.089 mm mrad at a repetition rate of 1 GHz.Comment: 12 pages, 12 figure

Suivi du premier cas d'infection à Mycobacterium ulcerans confirmé par culture, PCR et génotypage en République du Congo-Brazzaville

This article presents follow-up data from the first patient in whom Mycobacterium ulcerans infection (MUI) was documented by PCR, genotyping and culture in the Republic of Congo-Brazzaville. Findings show the importance of regular clinical and microbiological evaluation for the disseminated form of the disease. The patient was probably infected in Pointe Noire where MUI has been described but never documented. Culture of specimens collected before antibiotic treatment showed that the bacterium was sensitive to the antibiotics being administered (streptomycin and rifampin) and was identical to isolates from Atlantic-coast regions of West Africa where MUI is endemic. The patient was treated with streptomycin and rifampin for 12 weeks in association with surgery. During treatment clinical examination was performed every day and microbiological analysis every two weeks. The duration of follow-up from the end of specific antibiotic treatment was 26 months. Medical treatment failed to prevent bone involvement and fistulae that were treated by surgery. However medical treatment may have limited dissemination of the disease. Serial microbiological evaluation was useful to detect bone involvement in this patient, but persistent positive gene amplification is not a proof of active disease. This study confirms that MUI is still endemic in the region of Pointe Noire. This finding underlines the need to optimize epidemiologic surveillance, laboratory diagnostic capabilities, and therapeutic management in the Republic of Congo-Brazzaville

Theory and particle tracking simulations of a resonant radiofrequency deflection cavity in TM110_{110} mode for ultrafast electron microscopy

We present a theoretical description of resonant radiofrequency (RF) deflecting cavities in TM$_{110}$ mode as dynamic optical elements for ultrafast electron microscopy. We first derive the optical transfer matrix of an ideal pillbox cavity and use a Courant-Snyder formalism to calculate the 6D phase space propagation of a Gaussian electron distribution through the cavity. We derive closed, analytic expressions for the increase in transverse emittance and energy spread of the electron distribution. We demonstrate that for the special case of a beam focused in the center of the cavity, the low emittance and low energy spread of a high quality beam can be maintained, which allows high-repetition rate, ultrafast electron microscopy with 100 fs temporal resolution combined with the atomic resolution of a high-end TEM. This is confirmed by charged particle tracking simulations using a realistic cavity geometry, including fringe fields at the cavity entrance and exit apertures

Application of relativistic scattering theory of x rays to diffraction anomalous fine structure in Cu

We apply our recent first-principles formalism of magnetic scattering of circularly polarized x rays to a single Cu crystal. We demonstrate the ability of our formalism to interpret the crystalline environment related near-edge fine structure features in the resonant x-ray scattering spectra at the Cu K absorption edge. We find good agreement between the computed and measured diffraction anomalous fine structure features of the x-ray scattering spectra

Novel bioplastic from single cell protein as a potential packaging material

Microbial treatment of biodegradable wastes not only ensures neutralization of harmful substances such as volatile organic compounds but also enables valorization and bio-circularity within the society. Single cell protein (SCP) is a value-added product that can be obtained from biodegradable waste materials such as food waste via microbial fermentation. In this article, SCP derived from potato starch waste was demonstrated as a viable alternative to existing plant/animal proteins used in the production of films, for example, packaging applications. Flexible glycerol-plasticized SCP films were prepared through compression molding, and tensile tests revealed strength and stiffness similar to other plasticized protein films. The oxygen barrier properties were significantly better compared to the common polyethylene packaging material, but as with other highly polar materials, the SCP material must be shielded from moisture if used in, for example, food packaging. The biodegradation test revealed a similar degradation pattern as observed for a household compostable bag. The results showed that SCP-based bioplastic films can be considered as potential alternative to the existing plant/animal protein films and certain synthetic polymers. An important advantage with these protein materials is that they do not cause problems similar to microplastics

Synchrotron Studies of the First-Order Melting Transitions of Hexatic Monolayers and Multilayers in Freely Suspended Liquid-Crystal Films

Synchrotron x-ray diffraction has been used to study the surface and the interior hexatic-to-liquid (smectic-I to smectic-C) melting transitions of freely suspended liquid-crystal films of N-[4'-(n-heptyl)benzylidene]-4-(n-heptyl)aniline (7O.7) five molecular layers thick. Both the surface hexatic monolayers and the interior hexatic layers melt via hysteretic first-order transitions. After the two surface layers undergo a first-order transition to the smectic-I phase, the surface hexatic correlation length $\xi$ evolves smoothly from $\sim 100 to \sim 300 \mathring{A}$ with a roughly square-root form, $\xi \sim \mid T-T_c \mid ^{1/2}$.Engineering and Applied Science

Genomic Diversity and Evolution of Mycobacterium ulcerans Revealed by Next-Generation Sequencing

Mycobacterium ulcerans is the causative agent of Buruli ulcer, the third most common mycobacterial disease after tuberculosis and leprosy. It is an emerging infectious disease that afflicts mainly children and youths in West Africa. Little is known about the evolution and transmission mode of M. ulcerans, partially due to the lack of known genetic polymorphisms among isolates, limiting the application of genetic epidemiology. To systematically profile single nucleotide polymorphisms (SNPs), we sequenced the genomes of three M. ulcerans strains using 454 and Solexa technologies. Comparison with the reference genome of the Ghanaian classical lineage isolate Agy99 revealed 26,564 SNPs in a Japanese strain representing the ancestral lineage. Only 173 SNPs were found when comparing Agy99 with two other Ghanaian isolates, which belong to the two other types previously distinguished in Ghana by variable number tandem repeat typing. We further analyzed a collection of Ghanaian strains using the SNPs discovered. With 68 SNP loci, we were able to differentiate 54 strains into 13 distinct SNP haplotypes. The average SNP nucleotide diversity was low (average 0.06–0.09 across 68 SNP loci), and 96% of the SNP locus pairs were in complete linkage disequilibrium. We estimated that the divergence of the M. ulcerans Ghanaian clade from the Japanese strain occurred 394 to 529 thousand years ago. The Ghanaian subtypes diverged about 1000 to 3000 years ago, or even much more recently, because we found evidence that they evolved significantly faster than average. Our results offer significant insight into the evolution of M. ulcerans and provide a comprehensive report on genetic diversity within a highly clonal M. ulcerans population from a Buruli ulcer endemic region, which can facilitate further epidemiological studies of this pathogen through the development of high-resolution tools

Single Nucleotide Polymorphism Typing of Mycobacterium ulcerans Reveals Focal Transmission of Buruli Ulcer in a Highly Endemic Region of Ghana

Buruli ulcer (BU) is an emerging necrotizing disease of the skin and subcutaneous tissue caused by Mycobacterium ulcerans. While proximity to stagnant or slow flowing water bodies is a risk factor for acquiring BU, the epidemiology and mode of M. ulcerans transmission is poorly understood. Here we have used high-throughput DNA sequencing and comparisons of the genomes of seven M. ulcerans isolates that appeared monomorphic by existing typing methods. We identified a limited number of single nucleotide polymorphisms (SNPs) and developed a real-time PCR SNP typing method based on these differences. We then investigated clinical isolates of M. ulcerans on which we had detailed information concerning patient location and time of diagnosis. Within the Densu river basin of Ghana we observed dominance of one clonal complex and local clustering of some of the variants belonging to this complex. These results reveal focal transmission and demonstrate, that micro-epidemiological analyses by SNP typing has great potential to help us understand how M. ulcerans is transmitted