766 research outputs found
Big data logistics: a health-care transport capacity sharing model
The growth of cities in the 21st century has put more pressure on resources and conditions of urban life. There are several reasons why the health-care industry is the focus of this investigation. For instance, in the UK various studies point to the lack of failure of basic quality control procedures and misalignment between customer needs and provider services and duplication of logistics practices. The development of smart cities and big data present unprecedented challenges and opportunities for operations managers; they need to develop new tools and techniques for network planning and control. Our paper aims to make a contribution to big data and city operations theory by exploring how big data can lead to improvements in transport capacity sharing. We explore using Markov models the integration of big data with future city (health-care) transport sharing. A mathematical model was designed to illustrate how sharing transport load (and capacity) in a smart city can improve efficiencies in meeting demand for city services. The results from our analysis of 13 different sharing/demand scenarios are presented. A key finding is that the probability for system failure and performance variance tends to be highest in a scenario of high demand/zero sharing
A comparative study of CO adsorption on flat, stepped and kinked Au surfaces using density functional theory
Our ab initio calculations of CO adsorption energies on low miller index
(111), (100), stepped (211), and kinked (532) gold surfaces show a strong
dependence on local coordination with a reduction in Au atom coordination
leading to higher binding energies. We find trends in adsorption energies to be
similar to those reported in experiments and calculations for other metal
surfaces. The (532) surface provides insights into these trends because of the
availability of a large number of kink sites which naturally have the lowest
coordination (6). We also find that, for all surfaces, an increase in CO
coverage triggers a decrease in the adsorption energy. Changes in the
work-function upon CO adsorption, as well as the frequencies of the CO
vibrational modes are calculated, and their coverage dependence is reported.Comment: 18 pages, 4 figure
Proper Weyl Collineations in Kantowski-Sachs and Bianchi Type III Space-Times
A study of proper Weyl collineations in Kantowski-Sachs and Bianchi type III
space-times is given by using the rank of the 6X6 Weyl matrix and direct
integration techniques. Studying proper Weyl collineations in each of the above
space-times, it is shown that there exists no such possibility when the above
space-times admit proper Weyl collineations.Comment: 5 page
tert-Butyl N-[1-diazoacetyl-3-(methylsulfanyl)propyl]carbamate
In the enantiomerically pure title compound, C11H19N3O3S, the chain C—N—C(O)—O—C—C (from the asymmetric carbon to a methyl of the tert-butyl group) displays an extended conformation. In the crystal, molecules are linked into chains parallel to the c axis by classical N—H⋯Odiazocarbonyl hydrogen bonding and an unusual intermolecular three-centre interaction involving the amino acid (aa) carbonyl Oaa and the diazocarbonyl grouping C(O)—CH—N N, with H⋯Oaa = 2.51 Å and N⋯Oaa = 2.8141 (14) Å
Mass spectrometry captures off-target drug binding and provides mechanistic insights into the human metalloprotease ZMPSTE24.
Off-target binding of hydrophobic drugs can lead to unwanted side effects, either through specific or non-specific binding to unintended membrane protein targets. However, distinguishing the binding of drugs to membrane proteins from that of detergents, lipids and cofactors is challenging. Here, we use high-resolution mass spectrometry to study the effects of HIV protease inhibitors on the human zinc metalloprotease ZMPSTE24. This intramembrane protease plays a major role in converting prelamin A to mature lamin A. We monitored the proteolysis of farnesylated prelamin A peptide by ZMPSTE24 and unexpectedly found retention of the C-terminal peptide product with the enzyme. We also resolved binding of zinc, lipids and HIV protease inhibitors and showed that drug binding blocked prelamin A peptide cleavage and conferred stability to ZMPSTE24. Our results not only have relevance for the progeria-like side effects of certain HIV protease inhibitor drugs, but also highlight new approaches for documenting off-target drug binding
Graphle: Interactive exploration of large, dense graphs
<p>Abstract</p> <p>Background</p> <p>A wide variety of biological data can be modeled as network structures, including experimental results (e.g. protein-protein interactions), computational predictions (e.g. functional interaction networks), or curated structures (e.g. the Gene Ontology). While several tools exist for visualizing large graphs at a global level or small graphs in detail, previous systems have generally not allowed interactive analysis of dense networks containing thousands of vertices at a level of detail useful for biologists. Investigators often wish to explore specific portions of such networks from a detailed, gene-specific perspective, and balancing this requirement with the networks' large size, complex structure, and rich metadata is a substantial computational challenge.</p> <p>Results</p> <p>Graphle is an online interface to large collections of arbitrary undirected, weighted graphs, each possibly containing tens of thousands of vertices (e.g. genes) and hundreds of millions of edges (e.g. interactions). These are stored on a centralized server and accessed efficiently through an interactive Java applet. The Graphle applet allows a user to examine specific portions of a graph, retrieving the relevant neighborhood around a set of query vertices (genes). This neighborhood can then be refined and modified interactively, and the results can be saved either as publication-quality images or as raw data for further analysis. The Graphle web site currently includes several hundred biological networks representing predicted functional relationships from three heterogeneous data integration systems: <it>S. cerevisiae </it>data from bioPIXIE, <it>E. coli </it>data using MEFIT, and <it>H. sapiens </it>data from HEFalMp.</p> <p>Conclusions</p> <p>Graphle serves as a search and visualization engine for biological networks, which can be managed locally (simplifying collaborative data sharing) and investigated remotely. The Graphle framework is freely downloadable and easily installed on new servers, allowing any lab to quickly set up a Graphle site from which their own biological network data can be shared online.</p
C and S induces changes in the electronic and geometric structure of Pd(533) and Pd(320)
We have performed ab initio electronic structure calculations of C and S
adsorption on two vicinal surfaces of Pd with different terrace geometry and
width. We find both adsorbates to induce a significant perturbation of the
surface electronic and geometric structure of Pd(533) and Pd(320). In
particular C adsorbed at the bridge site at the edge of a Pd chain in Pd(320)
is found to penetrate the surface to form a sub-surface structure. The
adsorption energies show almost linear dependence on the number of
adsorbate-metal bonds, and lie in the ranges of 5.31eV to 8.58eV for C and
2.89eV to 5.40eV for S. A strong hybridization between adsorbate and surface
electronic states causes a large splitting of the bands leading to a drastic
decrease in the local densities of electronic states at the Fermi-level for Pd
surface atoms neighboring the adsorbate which may poison catalytic activity of
the surface. Comparison of the results for Pd(533) with those obtained earlier
for Pd(211) suggests the local character of the impact of the adsorbate on the
geometric and electronic structures of Pd surfaces.Comment: 14 pages 9 figs, Accepted J. Phys: Conden
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