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1.
Abstract The combination of levulinic acid and sodium dodecyl sulfate (SDS) in recent years has shown considerable promise as an antimicrobial intervention. Both ingredients have been designated by the U.S. Food and Drug Administration (FDA) as Generally Recognized as Safe (GRAS) for being used as a flavoring agent and multipurpose food additive, respectively. The use of levulinic acid and SDS alone has limited antimicrobial efficacy on tested microorganisms, and synergism between levulinic acid and SDS has been observed. The postulated mechanism of action of the synergistic effect is presented. The antimicrobial efficacy of levulinic acid plus SDS remains high even when organic materials are present. The other features, including penetration, foamability, and being readily soluble, extend its potential applications to disinfection of difficult-to-access areas and control of foodborne pathogens both in a planktonic state and in a biofilm. These features indicate that the levulinic acid plus SDS combination may have the potential to be applied within the food processing environment on a large scale. 相似文献
2.
Dr. Carolyn Vargas Prof. Dr. Gerald Radziwill Dr. Gerd Krause Dr. Anne Diehl Prof. Dr. Sandro Keller Dr. Nestor Kamdem Prof. Dr. Constantin Czekelius Annika Kreuchwig Dr. Peter Schmieder Dr. Declan Doyle Prof. Dr. Karin Moelling Dr. Volker Hagen Dr. Markus Schade Prof. Dr. Hartmut Oschkinat 《ChemMedChem》2014,9(7):1458-1462
PDZ (PSD‐95, Dlg, ZO‐1) domains are ubiquitous interaction modules that are involved in many cellular signal transduction pathways. Interference with PDZ‐mediated protein–protein interactions has important implications in disease‐related signaling processes. For this reason, PDZ domains have gained attention as potential targets for inhibitor design and, in the long run, drug development. Herein we report the development of small molecules to probe the function of the PDZ domain from human AF6 (ALL1‐fused gene from chromosome 6), which is an essential component of cell–cell junctions. These compounds bind to AF6 PDZ with substantially higher affinity than the peptide (Ile‐Gln‐Ser‐Val‐Glu‐Val) derived from its natural ligand, EphB2. In intact cells, the compounds inhibit the AF6–Bcr interaction and interfere with epidermal growth factor (EGF)‐dependent signaling. 相似文献
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M. Calvo C. Hoffman A. Benoit N. Boudou A. Cruciani S. Doyle C. Giordano C. Hoarau H. LeDuc P. Mauskopf A. Monfardini M. Roesch K. Schuster 《Journal of Low Temperature Physics》2012,167(3-4):379-385
Microwave Kinetic Inductance Detectors (MKIDs) have recently drawn the attention of the low-temperature detectors community. Easy fabrication, high sensitivity, small time constants and most notably the intrinsic capability to frequency multiplexing open new possibilities to applications that need very large array sizes and/or high speed read-out. Lumped Element Kinetic Inductance Detectors (LEKIDs) designed and fabricated in our collaboration have already shown good on sky performances, but new developments are needed for future multi-thousands-pixels instruments. In this contribution we present such ongoing developments: a new LEKIDs design, optimized to be dual polarization sensitive; use of new materials such as TiN in order to reach better signal to noise ratios; new solutions to minimize the cross-talk between pixels in order to achieve a better control of the resonance positions in frequency space. We discuss present lab measurements of the optical performances and recent improvements of the read-out electronics. 相似文献
5.
Barry M. Doyle 《Planning Perspectives》2013,28(1):47-65
Drawing on a range of sources, this article addresses the way in which various groups set about mapping the slums of Edwardian Norwich to bring understanding and order to the disordered world of the city's 750 courts and yards. It focuses on the social scientific investigations incorporated in the reports of the Medical Officer of Health; the evidence of social investigators; the findings of charitable bodies and the writings of local journalists, whether addressing the slum issue directly or reporting news stories set in slum areas. It shows how these individuals and groups identified, categorized and interpreted the slums and their dwellers and, by making the unknown known, encouraged a more vigorous intervention by the local state in the lives of the poor. It demonstrates the way in which these concerns and ideals came together in the moral panic which followed the Norwich Flood of August 1912, an event which revealed the dreadful state of the inner-city housing to a city-wide audience and culminated in the City's first public housing scheme. It shows how the impetus to demolish slums and build public housing on the outskirts of the city was conditioned by both the application of medical criteria and traditional moral constructions of the characters of slum dwellers. 相似文献
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Quantitative soil ingestion studies employing a mass balance tracer approach have been used to provide a defensible means to estimate soil ingestion for human health risk assessments. Past studies have focused on soil ingestion in populations living in urban/suburban environments. There is a paucity of reliable quantitative soil ingestion data to support human health risk assessments of other lifestyles that may be predisposed to ingesting soil, such as agricultural workers or indigenous populations following traditional lifestyles. The results of a preliminary analysis of sampling and analytical variability that would result from assessing activities typical of populations in rural or wilderness areas and conducted over wide areas show that approximately 225 subject days would be required to detect a difference of 20 mg/d in soil ingestion. Given the typically small populations in these areas, future soil ingestion studies should be focused on specific activities with a high potential for soil ingestion. 相似文献
8.
J.V. Branson K. HattarP. Rossi G. VizkelethyC.J. Powell B. Hernandez-SanchezB.L. Doyle 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(20):2326-2329
The ion photon emission microscope (IPEM) is a technique developed at Sandia National Laboratories (SNL) to study radiation effects in integrated circuits with high energy, heavy ions, such as those produced by the 88” cyclotron at Lawrence Berkeley National Laboratory (LBNL). In this method, an ion-luminescent film is used to produce photons from the point of ion impact. The photons emitted due to an ion impact are imaged on a position-sensitive detector to determine the location of a single event effect (SEE). Due to stringent resolution, intensity, wavelength, decay time, and radiation tolerance demands, an engineered material with very specific properties is required to act as the luminescent film. The requirements for this material are extensive. It must produce a high enough induced luminescent intensity so at least one photon is detected per ion hit. The emission wavelength must match the sensitivity of the detector used, and the luminescent decay time must be short enough to limit accidental coincidences. In addition, the material must be easy to handle and its luminescent properties must be tolerant to radiation damage. Materials studied for this application include plastic scintillators, GaN and GaN/InGaN quantum well structures, and lanthanide-activated ceramic phosphors. Results from characterization studies on these materials will be presented; including photoluminescence, cathodoluminescence, ion beam induced luminescence, luminescent decay times, and radiation damage. Results indicate that the ceramic phosphors are currently proving to be the ideal material for IPEM investigations. 相似文献
9.
In this paper, surface activated nanointegration of computational, electrical, optical, and mechanical structures for intelligent telemetry, communication, and sensing systems is described. The design approach and integration of top-down systems and bottom-up devices is considered with the need for biologically compatible bonding. For the simplified interface between bottom-up and top-down design a bus-bar unit architecture is presented. Emerging biomedical applications using intelligent sensors for remote patient monitoring and systems for rehabilitation comparing surface vs. implanted sensors are considered. Requirements for nanointegration of biomedical systems are suggested. Diverse combinations of rigid and flexible substrates of copper, gold, gallium arsenide, gallium phosphide and liquid crystal polymer were bonded by using two different nanobonding techniques. In these techniques, the surface cleaning with/without simultaneous deposition of nano-adhesion layers and contact in ultra-high vacuum/high vacuum were accomplished. These nanobonding technologies provide void-free, strong, and nanometer scale covalent bonding at room temperature or at low temperatures (~240 °C), and do not require chemicals, adhesives, or high external pressure. A considerable electrical current conduction and low loss of the nanobonded laminate was observed at high frequency. This investigation reveals that a biocompatible, high performance, and miniaturized systems may be realized for intelligent, implantable biomedical sensors because of the strong bond, low toxicity and favorable electrical properties in surface activated nanobonding. 相似文献
10.
JA Robl R Sulsky E Sieber-McMaster DE Ryono MP Cimarusti LM Simpkins DS Karanewsky S Chao MM Asaad AA Seymour M Fox PL Smith NC Trippodo 《Canadian Metallurgical Quarterly》1999,42(2):305-311
A series of 7-(di)alkyl and spirocyclic substituted azepinones were generated and incorporated as conformationally restricted dipeptide surrogates in mercaptoacyl dipeptides. Clear structure-activity relationships with respect to both angiotensin-converting enzyme (ACE) and neutral endopeptidase (NEP) activity in vitro were observed. The best in this series, compound 1g, a geminally dimethylated C-7-substituted azepinone, demonstrated excellent blood pressure lowering in animal models. Compound 1g (BMS-189921) is characterized by a good duration of activity and excellent oral efficacy in models relevant to ACE or NEP inhibition, and its activity is comparable to that of the clinically efficacious agent omapatrilat. Consequently this inhibitor has been advanced clinically for the treatment of hypertension and congestive heart failure. 相似文献