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31.
Proportional symbol maps visualize numerical data associated with point locations by placing a scaled symbol—typically an
opaque disk or square—at the corresponding point on a map. The area of each symbol is proportional to the numerical value
associated with its location. Every visually meaningful proportional symbol map will contain at least some overlapping symbols.
These need to be drawn in such a way that the user can still judge their relative sizes accurately. 相似文献
32.
33.
Two studies were conducted to investigate the predictive role of person-specific, product-specific, and situation-specific influences on the use of instruction manuals in the field of electrical consumer products. In a laboratory study, 42 participants were observed while putting a vacuum cleaner into operation. Situational primes (i.e., receiving a verbal cue that the packaging contains an instruction manual) increased the probability of the user manual being read. Additional verbal information that the manual contains information on energy-saving behaviours was especially motivating for persons with high environmental concern. Self-report data, collected on a wide range of products, suggest that product complexity is the best predictor of instruction manual use. In a second study with 30 participants, different positions of product labels were compared, i.e. placing the information on the packaging or directly onto the product. Information placed directly onto the product had a significantly higher influence on participants' actual behaviour than providing the same information on the packaging. 相似文献
34.
A novel ion trap time-of-flight hybrid mass spectrometer (qIT-TOF MS) has been applied for peptide sequencing in proteolytic digests generated from spore mixtures of Bacilli. The method of on-probe solubilization and in situ proteolytic digestion of small, acid-soluble spore proteins has been recently developed in our laboratory, and microorganism identification in less than 20 min was accomplished. In this study, tryptic peptides were generated in situ from complex spore mixtures of B. subtilis 168, B. globigii, B. thuringiensis subs. Kurstaki, and B. cereus T, respectively. MALDI analysis of bacterial peptides generated was performed with an average mass resolving power of 6200 and a mass accuracy of up to 10 ppm using a trap-TOF tandem configuration. Precursor ions of interest were usually selected and stored in the quadrupole ion trap with their complete isotope distribution by choosing a window of +/- 2 Da. Sequence-specific information on isolated protonated peptides was gained via tandem MS experiments with an average mass resolving power of 4450 for product ion analysis, and protein and bacterial sources were identified by database searching. 相似文献
35.
A strategy is proposed for the rapid identification of Bacillus spores, which relies on the selective release of a family of proteins, referred to as small, acid-soluble spore proteins (SASPs). In this work, SASPs were selectively solubilized from Bacillus spores on the MALDI sample plate by using 10% TFA. Proteolytic digests of SASPs generated in situ from spores of B. subtilis 168, B. globigii, B. thuringiensis subs. Kurstaki HD-1, B. cereus T, and the nonpathogenic strain B. anthracis Sterne were prepared in 5-25 min by using trypsin immobilized on Agarose beads and subsequently analyzed by MALDI-TOFMS using a curved-field reflectron. Protein identification was obtained by partial sequencing of distinctive tryptic peptides from Bacillus spores via post-source decay analysis combined with genome-based database searches by Mascot Sequence Query. Various unique SASPs were identified, allowing the characterization of Bacillus species by obtaining sequence-specific information on single peptides. The applicability of this approach for the rapid identification of Bacillus species was further established by analyzing spore mixtures. 相似文献
36.
Jovan Jovanović Bettina Frohnapfel Rubitha Srikantharajah Djordje Jovanović Hermann Lienhart Antonio Delgado 《Microfluidics and nanofluidics》2011,11(6):773-780
The stabilizing effect of microgroove surface morphology on viscous drag reduction was studied experimentally in the inlet
region of a plane channel flow. The stabilization is thought to be due to the ability of a microgrooved surface pattern to
suppress the velocity fluctuations in the spanwise direction on a restricted portion of the wetted surface, which prevents
vorticity development at the wall and consequently across the entire flow field. This smart microflow control strategy, which
works successfully only under very particular circumstances, was implemented in a microgroove-modified channel flow in which
the front part has a microgrooved surface topology. The results of pressure drop measurements indicate that microgrooved surfaces
can effectively stabilize laminar boundary layer development, leading to a significant reduction in the viscous drag. In the
rear flat part of the microgroove-modified channel test section, a maximum drag reduction of DR @ 35%{\rm DR\simeq 35\%} was measured. This corresponds to an overall drag reduction of DR @ 16%{\rm DR\simeq 16\%} at a length Reynolds number of Rex @ 106.Re_x\simeq 10^6. The drag reduction effect persisted in a narrow range of flow velocities and for the reported experimental conditions corresponds
to microgroove dimensions between 1.5 and 2.5 viscous length-scales. 相似文献
37.
Francisco Perez-Sorrosal Marta Patiño-Martinez Ricardo Jimenez-Peris Bettina Kemme 《The VLDB Journal The International Journal on Very Large Data Bases》2011,20(6):841-865
The new vision of cloud computing demands scalable, available and autonomic software platforms in order to deploy applications and services accessible anywhere
and anytime. Multi-tier architectures are an important building block for many applications that are deployed in the cloud.
This paper presents a novel caching and replication infrastructure that facilitates the scalable and elastic deployment of
multi-tier architectures. Our Elastic SI-Cache is a novel multi-version cache that attains high performance and consistency in multi-tier systems. In contrast to most existing
caches, Elastic SI-Cache provides snapshot isolation coherently across all tiers. Furthermore, Elastic SI-Cache supports scalable
replication of the different tiers where replicas can be added or removed dynamically as needed, making the cache amenable
for cloud computing environments. Elastic SI-Cache has been implemented and integrated into an open source JEE application
server and its performance evaluated with the industrial benchmark SPECjAppServer. 相似文献
38.
Discovery of interactive graphs for understanding and searching time-indexed corpora 总被引:3,自引:2,他引:1
Rich information spaces (like the Web or scientific publications) are full of “stories”: sets of statements that evolve over
time, manifested as, for example, collections of news articles reporting events that relate to an evolving crime investigation,
sets of news articles and blog posts accompanying the development of a political election campaign, or sequences of scientific
papers on a topic. In this paper, we formulate the problem of discovering such stories as Evolutionary Theme Pattern Discovery,
Summary and Exploration (ETP3). We propose a method and a visualisation tool for solving ETP3 by understanding, searching
and interacting with such stories and their underlying documents. In contrast to existing approaches, our method concentrates
on relational information and on local patterns rather than on the occurrence of individual concepts and global models. In addition, it relies on interactive graphs
rather than natural language as the abstracted story representations. Furthermore, we present an evaluation framework. Two
real-life case studies are used to illustrate and evaluate the method and tool. 相似文献
39.
Dr. Bettina Sommer Dr. Holger von Moeller Martina Haack Dr. Farah Qoura Clemens Langner Dr. Gleb Bourenkov Dr. Daniel Garbe Dr. Bernhard Loll Prof. Dr. Thomas Brück 《Chembiochem : a European journal of chemical biology》2015,16(1):110-118
Isobutanol is deemed to be a next‐generation biofuel and a renewable platform chemical. 1 Non‐natural biosynthetic pathways for isobutanol production have been implemented in cell‐based and in vitro systems with Bacillus subtilis acetolactate synthase (AlsS) as key biocatalyst. 2 – 6 AlsS catalyzes the condensation of two pyruvate molecules to acetolactate with thiamine diphosphate and Mg2+ as cofactors. AlsS also catalyzes the conversion of 2‐ketoisovalerate into isobutyraldehyde, the immediate precursor of isobutanol. Our phylogenetic analysis suggests that the ALS enzyme family forms a distinct subgroup of ThDP‐dependent enzymes. To unravel catalytically relevant structure‐function relationships, we solved the AlsS crystal structure at 2.3 Å in the presence of ThDP, Mg2+ and in a transition state with a 2‐lactyl moiety bound to ThDP. We supplemented our structural data by point mutations in the active site to identify catalytically important residues. 相似文献
40.
Timber bridges – Long term monitoring results of moisture diffusion in the load carrying cross‐sections Timber road bridges have been built worldwide for centuries. The high performance of wood is approved through many constructions. However, there are still doubts about using wood by the planning engineer, which reduce the number of realized projects. The moisture induced stresses in cross‐sections according to the varied ambient climate are mainly investigated under laboratory conditions. The results show that the moisture content changes differently over the cross‐section and leads to moisture induced stresses. The discussion about methods for the assessment of the moisture induced stresses in timber bridge cross‐ections is continuing. Results observed in the long term monitoring of seven timber bridges provide first guidelines for practitioners. For all constructions, the moisture content was measured regarding the ambient micro climate. As result, the influences according to the ambient micro climate are not insignificant. Positive is that the directly measured moisture content is less compared to the equilibrium moisture content calculated from the data of a close by meteorological station. The analysis of the moisture gradient over the cross‐section allows the definition of an active or passive zone. 相似文献