Synthesis of stable isotope labeled 3-acetyldeoxynivalenol

Stable isotope labeled 3-acetyldeoxynivalenol (3-AcDON) was synthesized in excellent yield from deoxynivalenol as starting material. This is the first synthesis of a stable isotope labeled type-B trichothecene suitable as internal standard for HPLC-MS/MS or GC-MS analysis of trichothecene mycotoxins. The isotopic purity of the 3-d(3)-AcDON was determined to be 94.9%.     

Current status of flexible waveguides for IR laser radiationtransmission

Minimal invasive surgery (MIS) is the preferred method for performing medical operations today due to its lower cost, fast healing, and minimal post-operative pain and discomfort to the treated patients. It is rapidly expanding with the development and miniaturization of two-dimensional (2-D) and three-dimensional (3-D) endoscopic imaging systems. Laser surgery has also proved itself to be a preferred tool of operation over standard tools in a lot of the cases. Development of a reliable flexible fiber or waveguide will enable surgeons to bring the laser beam transcendoscopically within body cavities. It will combine the endoscopy technique with the advantageous laser interaction with tissue to create a powerful surgical tool which will be the ultimate choice of operating procedure. A number of research groups have suggested flexible waveguides for the mid-IR region between 2.5 and 11 μm, which contains very important and useful laser wavelengths and is not covered by silica fibers. The chief goals for the development of such delivery devices are summarized. The different solutions suggested are broadly described and thoroughly analyzed for their performance and potential     

Communication Gaps in Disaster Management: Perceptions by Experts from Governmental and Non‐Governmental Organizations

The complexity of current disasters creates a challenge for crisis communication. This paper aims at identifying gaps in communication in disaster management experienced in practice in order to facilitate learning from those situations. The research was conducted using a qualitative online open‐ended questionnaire. It shows that despite the developments in the discipline, communication as an integral part of decision making in disaster management needs to be further developed. The paper provides a practical‐oriented overview of the communication constraints in complex crisis situations, which has not been provided so far. This research is part of an international project developing performance indicators for a quality measurement system for crisis communication.     

Feeling and facial efference: Implications of the vascular theory of emotion.

Is facial muscular movement capable of altering emotional state? Facial feedback theories answer this question in the affirmative but do not specify the intervening process. Cognitive appraisal theories do not address this question at all. The vascular theory of emotional efference (VTEE) holds that facial muscular movement, by its action on the cavernous sinus, may restrict venous flow and thereby influence cooling of the arterial blood supply to the brain. Subjective reactions resulting from facial action (phonetic utterance), resembling but unrelated to emotional efference, were found to differ in hedonic quality and to produce correlated changes in forehead temperature. Direct tests that introduced air into the nasal cavity revealed that cooled air was pleasurable, whereas warm air was aversive. It is conjectured that variations in cerebral temperature might influence the release and blocking of emotion-linked neurotransmitters—a consequence that would explain, in part, why some experiences are felt subjectively as pleasant and others as unpleasant. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of gaseous ozone and hot water on microbial and sensory quality of cantaloupe and potential transference of Escherichia coli O157:H7 during cutting

The effect of gaseous ozone and hot water, alone or in combination, on the sensory and microbial quality of cantaloupe melon was investigated. Escherichia coli O157:H7 transmission from the rind to edible melon flesh during cutting practices was also investigated. Four different treatments consisting of hot water (75 degrees C, 1min), gaseous ozone (10,000ppm, 30min), gaseous ozone supplied by carbon monoxide gas and the combination of hot water and gaseous ozone were evaluated. Sensory quality and growth evolution of aerobic mesophilic and psychrotrophic bacteria, coliforms and molds were studied. In general, hot water, gaseous ozone, and the combination of hot water and gaseous ozone were effective in reducing total microbial population. The combination of hot water and gaseous ozone was the most effective treatment to control microbial growth achieving 3.8, 5.1, 2.2 and 2.3log reductions for mesophilic and psychrotrophic bacteria, molds and coliforms, respectively. However no significant differences were observed between gaseous ozone and gaseous ozone supplied by with carbon monoxide gas. There was no evidence of damage in melons treated with hot water, ozone or their combination and they maintained initial texture and aroma. Therefore, the combination of hot water and gaseous ozone may be an efficient and promising treatment for controlling microbial growth and maintaining sensory quality of melons.     

The nature and location of SEBS–MA compatibilizer in polyethylene–wood flour composites

A maleic-anhydride-grafted styrene–ethylene—butylene–styrene (SEBS–MA) triblock copolymer has been used as a compatibilizer in low-density polyethylene–wood flour (LDPE–WF) composite system. The location of compatibilizer was studied using transmission electron microscopy (TEM). The unsaturated parts of the copolymer were stained with osmium tetraoxide (OsO₄) to enhance contrast between the different phases. TEM micrographs indicated that part of the compatibilizer was located at the interface between the wood particles and PE matrix and that wood was also stained by the OsO₄. The nature of the interface between the wood surface and the SEBS–MA was studied using Fourier transform infrared spectroscopy (FTIR). The results indicated that MA reacts with wood through esterification and hydrogen bonding and also possibly through interaction between the styrene and wood. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 201–209, 1998     

Chemical Control of Correlated Metals as Transparent Conductors

Correlated metallic transition metal oxides offer a route to thin film transparent conductors that is distinct from the degenerate doping of broadband wide gap semiconductors. In a correlated metal transparent conductor, interelectron repulsion shifts the plasma frequency out of the visible region to enhance optical transmission, while the high carrier density of a metal retains sufficient conductivity. By exploiting control of the filling, position, and width of the bands derived from the B site transition metal in ABO₃ perovskite oxide films, it is shown that pulsed laser deposition‐grown films of cubic SrMoO₃ and orthorhombic CaMoO₃ based on the second transition series cation 4d² Mo⁴⁺ have superior transparent conductor properties to those of the first transition series 3d¹ V⁴⁺‐based SrVO₃. The increased carrier concentration offered by the greater bandfilling in the molybdates gives higher conductivity while retaining sufficient correlation to keep the plasma edge below the visible region. The reduced binding energy of the n=4 frontier orbitals in the second transition series materials shifts the energies of oxide 2p to metal nd transitions into the near‐ultraviolet to enhance visible transparency. The A site size‐driven rotation of MoO₆ octahedra in CaMoO₃ optimizes the balance between plasma frequency and conductivity for transparent conductor performance.