1,176 research outputs found
Configuration Spaces Of Convex And Embedded Polygons In The Plane
This paper concerns the topology of configuration spaces of linkages whose underlying graph is a single cycle. Assume that the edge lengths are such that there are no configurations in which all the edges lie along a line. The main results are that, modulo translations and rotations, each component of the space of convex configurations is homeomorphic to a closed Euclidean ball and each component of the space of embedded configurations is homeomorphic to a Euclidean space. This represents an elaboration on the topological information that follows from the convexification theorem of Connelly, Demaine, and Rote
Clinical and molecular characterization of both methicillin-resistant andsensitive staphylococcus aureus mastitis
NO ABSTRACT AVAILABLEThis study targeted bovine mastitis as a possible source of livestock-associated methicillin-resistant Staphylococcus aureus (MRSA), to identify clinical signs associated with MRSA- and non-MRSA-associated mastitis. Thirty-eight mastitis cases (68 infected quarters) were investigated. Gram-positive cocci-shaped isolates were selected based on Baird Parker agar growth as well as Gram-stained bacterial smears. Molecular screening for Staphylococcus aureus (S. aureus) yielded 17 isolates, of which five (29.41%) were methicillin resistant. The five isolates were mecA positive, but mecC negative. Multilocus sequence typing (MLST) indicated that sequence type 1 (ST1) was the identified type of all isolates of MRSA. S. aureus-associated cases showed different clinical forms of mastitis, including subclinical, acute, chronic, and gangrenous. Additionally, subclinical mastitis was the only detected condition associated with MRSA, which may represent a potential hidden risk for humans. Phenotypically, isolates of MRSA showed resistance to all of the tested β-lactam antimicrobials, with marked resistance to tetracycline and gentamycin. Based on our knowledge, this is the first report to identify MRSA ST1 in Egypt. Bovine mastitis could be a source for the dissemination of MRSA to humans and other animals. Additionally, while methicillin-resistance may have no effect on the clinical outcome of mastitis, it does affect therapeutic success, particularly when β-lactam antimicrobials are used
Structure of Metastable States in Phase Transitions with High-Spin Low-Spin Degree of Freedom
Difference of degeneracy of the low-spin (LS) and high-spin (HS) states
causes interesting entropy effects on spin-crossover phase transitions and
charge transfer phase transitions in materials composed of the spin-crossover
atoms. Mechanisms of the spin-crossover (SC) phase transitions have been
studied by using Wajnflasz model, where the degeneracy of the spin states (HS
or LS) is taken into account and cooperative natures of the spin-crossover
phase transitions have been well described. Recently, a charge transfer (CT)
phase transition due to electron hopping between LS and HS sites has been
studied by using a generalized Wajnflasz model. In the both systems of SC and
CT, the systems have a high temperature structure (HT) and a low temperature
structure (LT), and the change between them can be a smooth crossover or a
discontinuous first order phase transition depending on the parameters of the
systems. Although apparently the standard SC system and the CT system are very
different, it is shown that both models are equivalent under a certain
transformation of variables. In both systems, the structure of metastable state
at low temperatures is a matter of interest. We study temperature dependence of
fraction of HT systematically in a unified model, and find several structures
of equilibrium and metastable states of the model as functions of system
parameters. In particular, we find a reentrant type metastable branch of HT in
a low temperature region, which would play an important role to study the
photo-irradiated processes of related materials.Comment: 19 pages, 11 figure
Robust, Conducting, and Transparent Polymer Composites using Surface-Modified and Individualized Double-Walled Carbon Nanotubes
This is the pre-peer reviewed version of the following article: ADVANCED MATERIALS. 20(23):4509-4512 (2008), which has been published in final form at 10.1002/adma.200801659.ArticleADVANCED MATERIALS. 20(23):4509-4512 (2008)journal articl
Raman study on electrochemical lithium insertion into multiwalled carbon nanotubes
This is the pre-peer reviewed version of the following article: JOURNAL OF RAMAN SPECTROSCOPY 39(9): 1183-1188, 2008, which has been published in final form http://www3.interscience.wiley.com/journal/118639317/abstract.ArticleJOURNAL OF RAMAN SPECTROSCOPY. 39(9): 1183-1188 (2008)journal articl
Strong and stable photoluminescence from the semiconducting inner tubes within double walled carbon nanotubes
This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in APPLIED PHYSICS LETTERS. 94(8):083106 (2009) and may be found at https://doi.org/10.1063/1.3085966 .ArticleAPPLIED PHYSICS LETTERS. 94(8):083106 (2009)journal articl
Pore structure and oxidation stability of double-walled carbon nanotube-derived bucky paper
ArticleChemical Physics Letters. 414(4-6):444-448 (2005)journal articl
- …