Antimicrobial Synergy Testing Services

Antimicrobial Synergy Testing Services

Neutralizing antibodies for infectious diseases

Neutralizing antibodies for infectious diseases

Cerebral differences in explicit and implicit emotional processing - An fMRI study

The processing of emotional facial expression is a major part of social communication and understanding. In addition to explicit processing, facial expressions are also processed rapidly and automatically in the absence of explicit awareness. We investigated 12 healthy subjects by presenting them with an implicit and explicit emotional paradigm. The subjects reacted significantly faster in implicit than in explicit trials but did not differ in their error ratio. For the implicit condition increased signals were observed in particular in the thalami, the hippocampi, the frontal inferior gyri and the right middle temporal region. The analysis of the explicit condition showed increased blood-oxygen-level-dependent signals especially in the caudate nucleus, the cingulum and the right prefrontal cortex. The direct comparison of these 2 different processes revealed increased activity for explicit trials in the inferior, superior and middle frontal gyri, the middle cingulum and left parietal regions. Additional signal increases were detected in occipital regions, the cerebellum, and the right angular and lingual gyrus. Our data partially confirm the hypothesis of different neural substrates for the processing of implicit and explicit emotional stimuli. Copyright (c) 2007 S. Karger AG, Basel

Dynamics of excited-state proton transfer systems via time-resolved photoelectron spectroscopy

The use of time-resolved photoelectron spectroscopy for analyzing excited state intramolecular proton transfer (ESIPT) and internal conversion dynamics in a model system was investigated. The photoelectron spectra of both the excited state enol and keto tautomers were presented as a function of pump laser wavelength and pump-probe time delay. It was found that the internal conversion dynamics in o-hydroxybenzaldehyde (OHBA) was influenced by interactions with a close-lying n??* state.open958

Concentrations of Metals in Aquatic Invertebrates from the Ozark National Scenic Riverways, Missouri

This report summarizes the findings of a study conducted as a pilot for part of a park-wide monitoring program being developed for the Ozark National Scenic Riverways (ONSR) of southeastern Missouri. The objective was to evaluate using crayfish (Orconectes spp.) and Asian clam (Corbicula fluminea) for monitoring concentrations of metals associated with lead-zinc mining. Lead-zinc mining presently (2007) occurs near the ONSR and additional mining has been proposed. Three composite samples of each type (crayfish and Asian clam), each comprising ten animals of approximately the same size, were collected during late summer and early fall of 2005 from five sites on the Current River and Jacks Fork within the ONSR and from one site on the Eleven Point River and the Big River, which are outside the ONSR. The Big River has been contaminated by mine tailings from historical leadzinc mining. Samples were analyzed by inductively coupled plasma mass spectrometry for lead, zinc, cadmium, cobalt, and nickel concentrations. All five metals were detected in all samples; concentrations were greatest in samples of both types from the Big River, and lowest in samples from sites within the ONSR. Concentrations of zinc and cadmium typically were greater in Asian clams than in crayfish, but differences were less evident for the other metals. In addition, differences among sites were small for cobalt in Asian clams and for zinc in crayfish, indicating that these metals are internally regulated to some extent. Consequently, both sample types are recommended for monitoring. Concentrations of metals in crayfish and Asian clams were consistent with those reported by other studies and programs that sampled streams in southeast Missouri

Concentrations of Metals in Aquatic Invertebrates from the Ozark National Scenic Riverways, Missouri

This report summarizes the findings of a study conducted as a pilot for part of a park-wide monitoring program being developed for the Ozark National Scenic Riverways (ONSR) of southeastern Missouri. The objective was to evaluate using crayfish (Orconectes spp.) and Asian clam (Corbicula fluminea) for monitoring concentrations of metals associated with lead-zinc mining. Lead-zinc mining presently (2007) occurs near the ONSR and additional mining has been proposed. Three composite samples of each type (crayfish and Asian clam), each comprising ten animals of approximately the same size, were collected during late summer and early fall of 2005 from five sites on the Current River and Jacks Fork within the ONSR and from one site on the Eleven Point River and the Big River, which are outside the ONSR. The Big River has been contaminated by mine tailings from historical leadzinc mining. Samples were analyzed by inductively coupled plasma mass spectrometry for lead, zinc, cadmium, cobalt, and nickel concentrations. All five metals were detected in all samples; concentrations were greatest in samples of both types from the Big River, and lowest in samples from sites within the ONSR. Concentrations of zinc and cadmium typically were greater in Asian clams than in crayfish, but differences were less evident for the other metals. In addition, differences among sites were small for cobalt in Asian clams and for zinc in crayfish, indicating that these metals are internally regulated to some extent. Consequently, both sample types are recommended for monitoring. Concentrations of metals in crayfish and Asian clams were consistent with those reported by other studies and programs that sampled streams in southeast Missouri

Biomonitoring of Lead, Zinc, and Cadmium in Streams Draining Lead-Mining and Non-Mining Areas, Southeast Missouri, USA

We evaluated exposure of aquatic biota to lead (Pb), zinc (Zn), and cadmium (Cd) in streams draining a Pb-mining district in southeast Missouri. Samples of plant biomass (detritus, periphyton, and filamentous algae), invertebrates (snails, crayfish, and riffle benthos), and two taxa of fish were collected from seven sites closest to mining areas (mining sites), four sites further downstream from mining (downstream sites), and eight reference sites in fall 2001. Samples of plant biomass from mining sites had highest metal concentrations, with means 10- to 60- times greater than those for reference sites. Mean metal concentrations in over 90% of samples of plant biomass from mining sites were significantly greater than those from reference sites. Mean concentrations of Pb, Zn, and Cd in most invertebrate samples from mining sites, and mean Pb concentrations in most fish samples from mining sites, were also significantly greater than those from reference sites. Concentrations of all three metals were lower in samples from downstream sites, but several samples of plant biomass from downstream sites had metal concentrations significantly greater than those from reference sites. Analysis of supplemental samples collected in the fall of 2002, a year of above-average stream discharge, had lower Pb concentrations and higher Cd concentrations than samples collected in 2001, near the end of a multi-year drought. Concentrations of Pb measured in fish and invertebrates collected from mining sites during 2001 and 2002 were similar to those measured at nearby sites in the 1970s, during the early years of mining in the Viburnum Trend. Results of this study demonstrate that long-term Pb mining activity in southeast Missouri has resulted in significantly elevated concentrations of Pb, Cd, and Zn in biota of receiving streams, compared to biota of similar streams without direct influence of mining. Our results also demonstrate that metal exposure in the study area differed significantly among sample types, habitats, and years, and that these factors should be carefully considered in the design of biomonitoring studies

1-2-3-flavor color superconductivity in compact stars

We suggest a scenario where the three light quark flavors are sequentially deconfined under increasing pressure in cold asymmetric nuclear matter, e.g., as in neutron stars. The basis for our analysis is a chiral quark matter model of Nambu--Jona-Lasinio (NJL) type with diquark pairing in the spin-1 single flavor (CSL) and spin-0 two/three flavor (2SC/CFL) channels, and a Dirac-Brueckner Hartree-Fock (DBHF) approach in the nuclear matter sector. We find that nucleon dissociation sets in at about the saturation density, n_0, when the down-quark Fermi sea is populated (d-quark dripline) due to the flavor asymmetry imposed by beta-equilibrium and charge neutrality. At about 3n_0 u-quarks appear forming a two-flavor color superconducting (2SC) phase, while the s-quark Fermi sea is populated only at still higher baryon density. The hybrid star sequence has a maximum mass of 2.1 M_sun. Two- and three-flavor quark matter phases are found only in gravitationally unstable hybrid star solutions.Comment: 4 pages, 2 figures, to appear in the proceedings of Quark Matter 2008: 20th International Conference on Ultra-Relativistic Nucleus Nucleus Collisions (QM 2008), Jaipur, India, 4-10 Feb 200