Constraint Networks of Topological Relations and Convexity

This paper studies the expressivity and computational complexity of networks of constraints of topological relations together with convexity. We consider constraint networks whose nodes are regular regions (a regular region is one equal to the closure of its interior) and whose constraints have the following forms: (i) the eight base relations of [12], which describe binary topological relations of containment and adjacency between regions; (ii) the predicate, X is convex. We establish tight bounds on the computational complexity of this language: Determining whether such a constraint network is consistent is decidable, but essentially as hard as determining whether a set of comparable size of algebraic constraints over the real numbers is consistent. We also show an important expressivity result for this language: If r and s are bounded, regular regions that are not related by an affine transformation, then they can be distinguished by a constraint network. That is, there is a constraint network and a particular node in that network such that there is a solution where the node is equal to r, but no solution where the node is equal to s.     

Influence of cover on mean column hydraulic characteristics in small pool riffle morphology streams

The field of ecohydraulics tries to link biological‐ and physical‐based processes in order to describe better the distribution of plants and animals in rivers. We tested the hypothesis that the influence of cover in pools and riffles would not be detectable using average velocity, turbulent kinetic energy and turbulent intensity, and compared these measurements to locations distant from cover. We measured water velocity fluctuations using an acoustic Doppler velocimeter. We found that turbulent intensity in the downstream direction (u′) and the transverse or cross‐stream direction (v′) were the most useful in detecting the presence of cover in pools and riffles. Differences were apparent between locations near cover in pools and riffles. Turbulent kinetic energy (k) and vertical turbulent intensity (w′) detected cover in pools but not in riffles. Average downstream velocity ( ) detected cover in riffles but not in pools. Average cross‐stream ( ) and vertical ( ) velocities did not detect any differences at all. We rejected the null hypothesis and concluded that turbulence caused by habitat features such as large rocks, wood or other channel complexities results in a statistically meaningful difference in flow characteristics in locations near cover. This finding was tempered by the fact that knowledge about how fish respond to turbulence is limited in comparison to our understanding of average velocity values. Despite the potential benefits to habitat modelling of incorporating turbulence‐based metrics, application of these findings will be challenging because turbulence modelling is difficult and current models may not be appropriate for application to rivers. Copyright © 2007 John Wiley & Sons, Ltd.     

The natural product berberine is a human prolyl oligopeptidase inhibitor

Prolyl oligopeptidase is a cytosolic serine peptidase that hydrolyzes proline-containing peptides at the carboxy terminus. This peptidase has been associated with schizophrenia, bipolar affective disorder, and related neuropsychiatric disorders, and therefore may have important clinical implications. Among the strategies used to find novel prolyl oligopeptidase inhibitors, traditional Chinese medicinal plants provide a rich source of unexplored compounds. We used (19)F NMR spectroscopy to search for new prolyl oligopeptidase inhibitors in a library of traditional Chinese medicine plant extracts. Several extracts were identified as powerful inhibitors of this peptidase. The alkaloid berberine was the prolyl oligopeptidase inhibitory molecule isolated from Rhizoma coptidis extract. Berberine inhibited prolyl oligopeptidase in a dose-dependent manner. As berberine is a natural compound that has been safely administered to humans, it opens up new perspectives for the treatment of neuropsychiatric diseases. The results described herein suggest that the initiation of clinical trials in patients with schizophrenia, bipolar affective disorder, or related diseases in which cognitive capabilities are affected should be undertaken with either the extract or pure BBR.     

Inactivation of bacteriophages via photosensitization of fullerol nanoparticles

The production of two reactive oxygen species through UV photosensitization of polyhydroxylated fullerene (fullerol) is shown to enhance viral inactivation rates. The production of both singlet oxygen and superoxide by fullerol in the presence of UV light is confirmed via two unique methods: electron paramagnetic resonance and reduction of nitro blue tetrazolium. These findings build on previous results both in the area of fullerene photosensitization and in the area of fullerene impact on microfauna. Results showed thatthe first-order MS2 bacteriophage inactivation rate nearly doubled due to the presence of singlet oxygen and increased by 125% due to singlet oxygen and superoxide as compared to UVA illumination alone. When fullerol and NADH are present in solution, dark inactivation of viruses occurs at nearly the same rate as that produced by UVA illumination without nanoparticles. These results suggest a potential for fullerenes to impact virus populations in both natural and engineered systems ranging from surface waters to disinfection technologies for water and wastewater treatment.     

Synthesis of Nanostructured Erbium Oxides and Investigation of Influence Oxides on the Immune System and of Some Animal Tissues

Nanostructured erbium oxides （Er2O3） with coherent scattering length 26, 31, 62 and 65 nm were obtained using as a precursor of erbium chloride and erbium oleate. The influences of Er203 on the immune system and some animal tissues were carried out. The experiments have been made on white mouse＇s and outbred rats. Complex pharmaco-toxicological research presented erbium oxide nanostructure size of coherent scattering regions 26, 31, 56 and 65 nm showed that when administered orally no acute toxicity, no effect on the immune system of the body, has no effect on blood cells. But, long-term （30 day） intragastric administration shows toxicities on the internal organs of experimental animals, which lead to structural changes and functional impairment due to tissue accumulation of nanoparticles.     

Shear wave velocity imaging using transient electrode perturbation: phantom and ex vivo validation

This paper presents a new shear wave velocity imaging technique to monitor radio-frequency and microwave ablation procedures, coined electrode vibration elastography. A piezoelectric actuator attached to an ablation needle is transiently vibrated to generate shear waves that are tracked at high frame rates. The time-to-peak algorithm is used to reconstruct the shear wave velocity and thereby the shear modulus variations. The feasibility of electrode vibration elastography is demonstrated using finite element models and ultrasound simulations, tissue-mimicking phantoms simulating fully (phantom 1) and partially ablated (phantom 2) regions, and an ex vivo bovine liver ablation experiment. In phantom experiments, good boundary delineation was observed. Shear wave velocity estimates were within 7% of mechanical measurements in phantom 1 and within 17% in phantom 2. Good boundary delineation was also demonstrated in the ex vivo experiment. The shear wave velocity estimates inside the ablated region were higher than mechanical testing estimates, but estimates in the untreated tissue were within 20% of mechanical measurements. A comparison of electrode vibration elastography and electrode displacement elastography showed the complementary information that they can provide. Electrode vibration elastography shows promise as an imaging modality that provides ablation boundary delineation and quantitative information during ablation procedures.     

Pilot-scale demonstration of surfactant-enhanced PCE solubilization at the Bachman Road site. 1. Site characterization and test design

A pilot-scale demonstration of surfactant-enhanced aquifer remediation (SEAR) was conducted to recover dense nonaqueous phase liquid (DNAPL) tetrachloroethene (PCE) from a sandy glacial outwash aquifer underlying a former dry cleaning facility at the Bachman Road site in Oscoda, MI. Part one of this two-part paper describes site characterization efforts and a comprehensive approach to SEAR test design, effectively integrating laboratory and modeling studies. Aquifer coring and drive point sampling suggested the presence of PCE-DNAPL in a zone beneath an occupied building. A narrow PCE plume emanating from the vicinity of this building discharges into Lake Huron. The shallow unconfined aquifer, characterized by relatively homogeneous fine-medium sand deposits, an underlying clay layer, and the absence of significant PCE transformation products, was judged suitable for the demonstration of SEAR. Tween 80 was selected for application based upon its favorable solubilization performance in batch and two-dimensional sand tank treatability studies, biodegradation potential, and regulatory acceptance. Three-dimensional flow and transport models were employed to develop a robust design for surfactant delivery and recovery. Physical and fiscal constraints led to an unusual hydraulic design, in which surfactant was flushed across the regional groundwater gradient, facilitating the delivery of concentrations of Tween 80 exceeding 1% (wt) throughout the treatment zone. The potential influence of small-scale heterogeneity on PCE-DNAPL distribution and SEAR performance was assessed through numerical simulations incorporating geostatistical permeability fields based upon available core data. For the examined conditions simulated PCE recoveries ranged from 94to 99%. The effluent treatment system design consisted of low-profile air strippers coupled with carbon adsorption to trap off-gas PCE and discharge of treated aqueous effluent to a local wastewater treatment plant. The systematic and comprehensive design methodology described herein may serve as a template for application at other DNAPL sites.     

Hypnotic susceptibility of schizophrenic patients.

Clinical lore and much of the previous literature has maintained that schizophrenics are far less susceptible to hypnosis than are normals. A few studies have reported success with hypnotizing schizophrenics, but have lacked a methodology which would permit comparison with normal Ss to be made. In this study, 26 Ss with a hospital diagnosis of schizophrenia were given the Stanford Hypnotic Susceptibility Scale—a verbatim induction technique and rating scale for which data on a normal, standardization group is available. The Ss gave results much like the normal group. Reasons for the difference between this and previous findings are discussed, including the hypothesis that previous workers found schizophrenics to be different in hypnotizability from normals because they treated them differently than they would normals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Proteomic Tools for the Quantitative Analysis of Artificial Peptide Libraries: Detection and Characterization of Target-Amplified PD-1 Inhibitors

We report a quantitative proteomics data analysis pipeline, which coupled to protein-directed dynamic combinatorial chemistry (DDC) experiments, enables the rapid discovery and direct characterization of protein-protein interaction (PPI) modulators. A low-affinity PD-1 binder was incubated with a library of >100 D-peptides under thiol-exchange favoring conditions, in the presence of the target protein PD-1, and we determined the S-linked dimeric species that resulted, amplified in the protein samples versus the controls. We chemically synthesized the target dimer candidates and validated them by thermophoresis binding and protein-protein interaction assays. The results provide a proof-of-concept for using this strategy in the high-throughput search of improved drug-like peptide binders that block therapeutically relevant protein-protein interactions.