cssi/SciSciGPT-SciSciNet huggingface dataset:
Interfacial Diffusion/Reaction and Electrical Properties of Pd Ultra-Thin Film on Sic at Different Annealing Temperatures

Pd/SiC has been used as a high temperature hydrocarbon and hydrogen gas sensor in environmental and aeronautical applications. In this work, the relationships between diffusion, reaction, and interfacial chemical composition with electrical properties for Pd ultra-thin films on 6H-SiC (∼< 30A) are studied at different annealing temperatures. Ultra-thin film Pd on 6H-SiC has been prepared by the RF sputtering method. The Schottky barrier heights are measured by XPS for an unannealed sample and samples annealed from 100°C to 400°C for 30 minutes, respectively. No significant change in the Schottky barrier height of the Pd/SiC contact was found in the temperature range. The morphology from UHV-STM and AFM show that the unannealed Pd thin film had good uniformity across the SiC substrate, and the Pd has dispersed, and then partially aggregated into rounded shaped precipitates with increasing annealing temperatures. At 400°C, all Pd metal has reacted and formed to silicides. From XPS, Pd2Si was found on the surface after annealing, and almost all Pd has reacted to become Pd2Si after annealing at 400°C. No other silicide was found. The intensity of Pd on XPS decreases enormously at 400°C. This is explained if Pd has diffused into SiC. The Pd diffusion and the formation of Pd silicides do not significantly affect the Schottky barrier height. The SiO2 was found at the top of surface after annealing, and increased in amount with increasing annealing temperature. The SiO2 formation was accelerated by the presence of Pd. Pd may play a role in absorbing oxygen, and activating Si from SiC to form SiO2. Key Words: Pd thin film, SiC, X-ray photoelectron spectroscopy, scanning tunneling microscopy, and atomic force microscopy.
Cognitive effects of a Ginkgo biloba/vinpocetine compound in normal adults: systematic assessment of perception, attention and memory.

A computerized test battery was used in a double-blind design to assess the cognitive effects of a nutrient compound containing Ginkgo biloba in 24 normal adults. Ten tasks (perceptual, attention and short-term memory) were presented in a standardized manner designed to maximize performance, with substantial pre-test practice employed to minimize response variability. Subjects were given either placebo or Ginkgo biloba extract capsules to consume for 14 days, after which they performed all tasks twice. They then received the other condition, and after 14 days completed the final test session. Response time and error rate stabilized after pre-test practice. A ‘working memory capacity’ paradigm demonstrated a reliable 50 ms response time decrease between the placebo and Ginkgo biloba testing, suggesting that Ginkgo biloba speeds short-term working memory processing in normal adults. Copyright © 2001 John Wiley & Sons, Ltd.
Synthesis of adenosine 3′,5′-monophosphate by guanylate cyclase, a new pathway for its formation

Abstract The 105 000 × g supernatant fractions from homogenates of various rat tissues catalyzed the formation of both cyclic GMP and cyclic AMP from GTP and ATP, respectively. Generally cyclic AMP formation with crude or purified preparations of soluble guanylate cyclase was only observed when enzyme activity was increased with sodium azide, sodium nitroprusside, N -methyl- N ′-nitro- N -nitrosoguanidine, sodium nitrite, nitric oxide gas, hydroxyl radical and sodium arachidonate. Sodium fluoride did not alter the formation of either cyclic nucleotide. After chromatography of supernatant preparations on Sephadex G-200 columns or polyacrylamide gel electrophoresis, the formation of cyclic AMP and clycic GMP was catalyzed by similar fractions. These studies indicate that the properties of guanylate cyclase are altered with activation. Since the synthesis of cyclic AMP and cyclic GMP reported in this study appears to be catalyzed by the same protein, one of the properties of activated guanylate cyclase is its ability to catalyze the formation of cyclic AMP from ATP. The properties of this newly described pathway for cyclic AMP formation are quite different from those previously described for adenylate cyclase preparations. The physiological significance of this pathway for cyclic AMP formation is not known. However, these studies suggest that the effects of some agents and processes to increase cyclic AMP accumulation in tissue could result from the activation of either adenylate cyclase or guanylate cyclase.
Next generation rope-like robot for in-space inspection

Design of continuum robots, i.e. robots with continuous backbones, has been an active area of research in robotics for minimally invasive surgery, search and rescue, object manipulation, etc. Along the same lines, NASA developed “Tendril”, the first long and thin continuum robot of its kind, intended for in-space inspection applications. In this paper, we describe and discuss the key disadvantages of state of the art mechanical design producing undesirable effects during operation. We then provide the specifics of a new, next generation, thin rope-like robot with a modified mechanical design for better performance having key features like controllable bending along its entire length, local compression and potentially smaller actuation package.
Tricyclic antidepressants and supine, standing, and exercise plasma norepinephrine levels

Fourteen depressed patients were treated for 1 to 8 wk (4.1 ± 0.6, mean ± SEM) with imipramine, doxepin, or amitriptyline to study the effects of tricyclic antidepressants (TCAs) on sympathetic nervous system (SNS) function. Eight had chronic but medically stable cardiac disease and six were medically healthy. Supine plasma norepinephrine (NE) and epinephrine (EPI) levels, mean arterial blood pressure (MAP), and heart rate were measured at rest, after standing, and during graded, supine maximal bicycle exercise. Eight nondepressed patients with cardiac disease were studied without drug intervention as controls. There were no baseline differences in any of these measures among the medically healthy depressed subjects, the depressed cardiac patients, and the eight nondepressed patients matched for cardiac disease. After TCAs, NE was increased by 51 ± 6% of basal values and heart rate rose, but EPI and MAP were unchanged. The supine to 10-min standing increment in NE increased from 309 ± 51 pg/ml at baseline to 406 ± 55 pg/ml during TCA treatment. These findings are compatible with an increase in SNS outflow after TCAs. Clinical Pharmacology and Therapeutics (1983) 33, 763–769; doi:10.1038/clpt.1983.104
PKR and RNase L contribute to protection against lethal West Nile Virus infection by controlling early viral spread in the periphery and replication in neurons.

West Nile virus (WNV) is a neurotropic, mosquito-borne flavivirus that can cause lethal meningoencephalitis. Type I interferon (IFN) plays a critical role in controlling WNV replication, spread, and tropism. In this study, we begin to examine the effector mechanisms by which type I IFN inhibits WNV infection. Mice lacking both the interferon-induced, double-stranded-RNA-activated protein kinase (PKR) and the endoribonuclease of the 2′,5′-oligoadenylate synthetase-RNase L system (PKR−/− × RL−/−) were highly susceptible to subcutaneous WNV infection, with a 90% mortality rate compared to the 30% mortality rate observed in congenic wild-type mice. PKR−/− × RL−/− mice had increased viral loads in their draining lymph nodes, sera, and spleens, which led to early viral entry into the central nervous system (CNS) and higher viral burden in neuronal tissues. Although mice lacking RNase L showed a higher CNS viral burden and an increased mortality, they were less susceptible than the PKR−/− × RL−/− mice; thus, we also infer an antiviral role for PKR in the control of WNV infection. Notably, a deficiency in both PKR and RNase L resulted in a decreased ability of type I IFN to inhibit WNV in primary macrophages and cortical neurons. In contrast, the peripheral neurons of the superior cervical ganglia of PKR−/− × RL−/− mice showed no deficiency in the IFN-mediated inhibition of WNV. Our data suggest that PKR and RNase L contribute to IFN-mediated protection in a cell-restricted manner and control WNV infection in peripheral tissues and some neuronal subtypes.
Highs and lows

Introduction to High-Temperature Superconductivity. By Thomas P. Sheahen. Plenum: 1994. Pp. 580. $59.50, £47.
Non-intrusive measurements of transitional and turbulent convective heat transfer in a rectangular microchannel

The thermal-transport characteristics of transitional and turbulent flow through smooth- and rough-wall rectangular microchannels (Dh = 600 μm) under constant-heat-flux conditions at three of the four walls were investigated by performing non-intrusive and spatially resolved measurements of fluid temperature via two-color fluorescent thermometry. These measurements, along with bulk pressure-drop measurements, were performed over the Reynolds-number range . The pressure-drop results revealed the onset of transition above for the smooth-wall case, consistent with the onset of transition at the macroscale. However, with increasing surface roughness, deviation from laminar behavior was noted at progressively lower Re which indicates that is a function of roughness. Mean temperature profiles calculated from data sets acquired in the transitional regime for the smooth- and rough-wall cases illustrated deviation from fully developed laminar behavior for . Nevertheless, these profiles still suggest similarities in the transitional pathway of the thermal-transport behavior for the smooth and rough cases save for a relative shift due to the onset of transition at lower Re with increasing surface roughness. Estimates of the bulk Nusselt number indicated enhancement in thermal transport over the smooth-wall case with increasing surface roughness in both the transitional and turbulent regimes, though the smooth-wall data agreed well with macroscale predictions over the range of turbulent Re considered. While the shift in the transitional pathway of the thermal transport behavior toward lower Re accounts for a portion of this enhancement, an increase in turbulent convection with increasing surface roughness might also contribute in this regard.
Blowout limits of turbulent jet diffusion flames for arbitrary source conditions

We present a formulation for the blowout limits of turbulent jet diffusion flames issuing from sources with arbitrary geometries and exit conditions into otherwise quiescent environments. It is argued that, while the liftoff characteristics of turbulent diffusion flames appear likely to be controlled by the straining out of flame sheets, the molecular mixing rate at the flame tip controls their blowout characteristics. The concept of a "far-field equivalent source" is introduced, and the local molecular mixing rate in the flow is expressed in terms of the associated far-field scaling laws. Blowout is expected when a resulting algebraic expression reaches a critical value. Results of a "flip" experiment verify the far-field equivalent source formulation. Measurements of the blowout limits over a range of geometries, fuels, and diluents show good agreement with the predictions from this formulation.
Information content of the near-field: Three-dimensional samples

The information content of the near-zone scattered field, for the case of a holographic measurement geometry, is examined using the variance of the least squares estimate of the susceptibility. Several examples will be presented.
High-performance liquid chromatographic assay for sodium mercaptoundecahydrododecaborate in rat tissues.

Mercaptoundecahydrododecaborate (BSH) is an important agent for the boron neutron-capture therapy (BNCT). A sensitive high-performance liquid chromatographic (HPLC) method was developed for measuring BSH concentrations in rat tissues. Various tissue samples containing the drug were homogenized in a 1:1 (g/ml) mixture with phosphate buffered saline. The samples were then deproteinised with 4 volumes of acetonitrile and centrifuged. An aliquot of the supernatant was dried and reconstituted in 200 μl of Tris-HCl buffer. The samples were subjected to precolumn derivatization using the thiol reactive monobromobimane (mBB). The drug-mBB adduct was resolved by isocratic elution froma C18 reversed-phase column. The optimized mobile phase was methanol-0.02 M phosphate buffer (43:57, v/v) containing 0.01 M tetrabutylammonium dihydrogen phosphate as the ion-pairing agent with the final pH adjusted to 7.0. The flow-rate was set at 2.0 ml/min. The adduct was monitored by UV absorption at 373 nm. The analysis was completed in less than 15 min. The detection limit was 0.5 μg/ml (0.25 μg of boron). The assay method was linear over a concentration range of 0.5 to 50 μg/ml. This assay method could be used to evaluate the BSH concentrations in different tissues in studies on the targeted delivery of BSH.
The Use of Pro-Ana Blogs for Online Social Support

The aim of this research was to document the content on pro-ana blogs and to uncover how the unique socio-technical features of blogs (interactivity, self-disclosure, masspersonal communication) facilitate social support among members. A final sample of 48 pro-ana blogs provided 624 individual units for coding. Results indicate that prevalent forms of social support were emotional support, esteem support, and informational support. A new category, reciprocal self-disclosure, was also revealed to be quite frequent. Blogs are spaces where social support is sought and communicated among members of the pro-ana network. Interpretation of blog communication and implications for treatment and research are discussed.
Political Attitudes and Complexity: Responses From a Motivational Perspective

The paragraphs that follow are an attempt to reply to two questions regarding differences in specific attitudes and complex thinking associated with the political Left and Right. In addressing the ...
Transmission probabilities and durations of immunity for three pathogenic group B Streptococcus serotypes

Group B Streptococcus (GBS) remains a major cause of neonatal sepsis and is an emerging cause of invasive bacterial infections. The 9 known serotypes vary in virulence, and there is little cross-immunity. Key parameters for planning an effective vaccination strategy, such as average length of immunity and transmission probabilities by serotype, are unknown. We simulated GBS spread in a population using a computational model with parameters derived from studies of GBS sexual transmission in a college dormitory. Here we provide estimates of the duration of immunity relative to the transmission probabilities for the 3 GBS serotypes most associated with invasive disease: Ia, III, and V. We also place upper limits on the durations of immunity for serotype Ia (570 days), III (1125 days) and V (260 days). Better transmission estimates are required to establish the epidemiological parameters of GBS infection and determine the best vaccination strategies to prevent GBS disease.
Cortical and Subcortical Contributions to Stop Signal Response Inhibition:Role of the Subthalamic Nucleus

Suppressing an already initiated manual response depends critically on the right inferior frontal cortex (IFC), yet it is unclear how this inhibitory function is implemented in the motor system. It has been suggested that the subthalamic nucleus (STN), which is a part of the basal ganglia, may play a role because it is well placed to suppress the “direct” fronto-striatal pathway that is activated by response initiation. In two experiments, we investigated this hypothesis with functional magnetic resonance imaging and a Stop-signal task. Subjects responded to Go signals and attempted to inhibit the initiated response to occasional Stop signals. In experiment 1, Going significantly activated frontal, striatal, pallidal, and motor cortical regions, consistent with the direct pathway, whereas Stopping significantly activated right IFC and STN. In addition, Stopping-related activation was significantly greater for fast inhibitors than slow ones in both IFC and STN, and activity in these regions was correlated across subjects. In experiment 2, high-resolution functional and structural imaging confirmed the location of Stopping activation within the vicinity of the STN. We propose that the role of the STN is to suppress thalamocortical output, thereby blocking Go response execution. These results provide convergent data for a role for the STN in Stop-signal response inhibition. They also suggest that the speed of Go and Stop processes could relate to the relative activation of different neural pathways. Future research is required to establish whether Stop-signal inhibition could be implemented via a direct functional neuroanatomic projection between IFC and STN (a “hyperdirect” pathway).
Characterization of the Putative 2×[4Fe-4S]-binding NQO9 Subunit of the Proton-translocating NADH-Quinone Oxidoreductase (NDH-1) of Paracoccus denitrificans: EXPRESSION, RECONSTITUTION, AND EPR CHARACTERIZATION

Molecular properties of the NQO9 subunit of Paracoccus denitrificans NDH-1, which is predicted to contain 2×[4Fe-4S] clusters, were investigated using recombinant expression techniques and EPR spectroscopy. The full-length form of NQO9 subunit co-expressed with thioredoxin in Escherichia coli at ambient temperature was found dominantly in the cytoplasmic membrane with low amplification. Genetic deletion of relatively hydrophobic and less conserved N-terminal stretches (30 or 40 amino acid residues long) of the NQO9 subunit resulted in the overexpression of the truncated soluble form of the subunit in a high yield in the cytoplasm. The purified soluble form of the NQO9 subunit contained only a small quantity of Fe and S2− (2.0–2.2 mol each per mol of subunit). However, the iron-sulfur content was considerably increased by in vitro reconstitution. The reconstituted NQO9 subunit contained 7.6–7.7 mol each of Fe and S2− per molecule and exhibited optical absorption spectra similar to those of 2×[4Fe-4S] ferredoxins. Two sets of relatively broad axial-type EPR signals with different temperature dependence and power saturation profile were detected in the dithionite-reduced preparations at a low temperature range (8–18 K). Due to a negative shift (
Radiolysis to knock-on damage transition in zeolites under electron beam irradiation

The electron-beam-induced damage in a zeolite under 60--200 keV energy beam irradiation has both radiolitic and knock-on components and can be described by linear superposition of these two processes. Theoretical predictions supported by experiments at 60 keV suggest that for electron beam energies smaller than 70 keV, the damage to the specimen follows a radiolitic path. For energies larger than 200 keV, knock-on based sputtering of the material will dominate, while considerable radiolitic movement of the atoms will still be present.
Opium alkaloids V. Structure of porphyroxine

Porphyroxine is a monophenolic alkaloid isolated from opium. It contains a methyl acetal group and has three asymmetric centers. The position of the phenolic hydroxyl group has been determined by NMR spectroscopy. Evidence has been presented for the configuration at position-14.
Linking NE1545 gene expression with cell volume changes in Nitrosomonas europaea cells exposed to aromatic hydrocarbons

Nitrosomonas europaea, a model ammonia oxidizing bacterium, was exposed to a wide variety of aromatic hydrocarbons in 3 h batch assays. The expression of NE1545, a phenol sentinel gene involved in fatty acid metabolism, was monitored via quantitative real-time polymerase chain reaction (qRT-PCR) and a Coulter Counter technique was used to monitor changes in cell volume. Decreases in cell volume and NE1545 gene expression correlated strongly with exposure to aromatic hydrocarbons that possessed a single polar group substitution (e.g. phenol and aniline). Aromatic hydrocarbons that contain no polar group substitutions (e.g. toluene) or multiple polar group substitutions (e.g. p-hydroquinone) caused negligible changes in NE1545 expression and cell volume. The oxidation of aromatic hydrocarbons by N. europaea from configurations without a single polar group to one with two polar groups (e.g. p-cresol oxidized to 4-hydroxybenzyl alcohol) and from configurations with no polar groups to one with a single polar group (e.g. ethylbenzene oxidized to 4-ethylphenol) greatly influenced NE1545 gene expression and observed changes in cell volume. Nitrification inhibition in N. europaea by the aromatic hydrocarbons was found to be completely reversible; however, the decreases in cell volume were not reversible suggesting a physical change in cell membrane composition. Ammonia monooxygenase blocking studies showed that the chemical exposure that was responsible for the cell volume decrease and up-regulation in gene expression and not the observed inhibition. N. europaea is the first bacterium shown to experience significant changes in cell volume when exposed to μM concentrations of aromatic hydrocarbons, three orders of magnitude lower than previous studies with other bacteria.
SecureCore: A multicore-based intrusion detection architecture for real-time embedded systems

Security violations are becoming more common in real-time systems - an area that was considered to be invulnerable in the past - as evidenced by the recent W32.Stuxnet and Duqu worms. A failure to protect such systems from malicious entities could result in significant harm to both humans as well as the environment. The increasing use of multicore architectures in such systems exacerbates the problem since shared resources on these processors increase the risk of being compromised. In this paper, we present the SecureCore framework that, coupled with novel monitoring techniques, is able to improve the security of realtime embedded systems. We aim to detect malicious activities by analyzing and observing the inherent properties of the real-time system using statistical analyses of their execution profiles. With careful analysis based on these profiles, we are able to detect malicious code execution as soon as it happens and also ensure that the physical system remains safe.
Population ecology of the Rice rat (Oryzomys palustris) in a coastal marsh

Rice rats were studied for four years by grid trapping in a tidal marsh on the northern Gulf of Mexico. Preliminary trapping indicated that marshes are preferred over other coastal habitats. Population densities fluctuated from spring lows of about 2/ha to highs of about 25/ha in the autumn and early winter. Reproduction occurred throughout the year, the major season being late spring to late autumn. Recruitment of juveniles was at a maximum from May to September. Males were more abundant than females in population samples, and had a higher mean body weight. This was because weight classes of 40 g and below were slightly skewed in favour of females and weight classes above 40 g heavily favoured males. The survival rate was low, with less than 20% of animals marked remaining on the grids for more than three months. Maximum longevity was 24 months. Results are compared to those of previous studies done on an offshore island and in the Florida everglades.
Microstructure and rheology relationships for shear thickening colloidal dispersions

The non-Newtonian shear rheology of colloidal dispersions is the result of the competition and balance between hydrodynamic (dissipative) and thermodynamic (conservative) forces that lead to a non-equilibrium microstructure under flow. We present the first experimental measurements of the shear-induced microstructure of a concentrated near-hard-sphere colloidal dispersion through the shear thickening transition using small-angle neutron scattering (SANS) measurements made in three orthogonal planes during steady shear. New instrumentation coupled with theoretical derivations of the stress-SANS rule enable rigorous testing of the relationship between this non-equilibrium microstructure and the observed macroscopic shear rheology. The thermodynamic and hydrodynamic components of the stress that drive shear thinning, shear thickening and first normal stress differences are separately defined via stress-SANS rules and compared to the rheological behaviour of the dispersion during steady shear. Observations of shear-induced hydrocluster formation is in good agreement with Stokesian dynamics simulation results by Foss & Brady (J. Fluid Mech., vol. 407, 2000, pp. 167–200). This unique set of measurements of shear rheology and non-equilibrium microstructure of a model system provides new insights into suspension mechanics as well as a method to rigorously test constitutive equations for colloidal suspension rheology.
Parietal connectivity mediates multisensory facilitation

Our senses interact in daily life through multisensory integration, facilitating perceptual processes and behavioral responses. The neural mechanisms proposed to underlie this multisensory facilitation include anatomical connections directly linking early sensory areas, indirect connections to higher-order multisensory regions, as well as thalamic connections. Here we examine the relationship between white matter connectivity, as assessed with diffusion tensor imaging, and individual differences in multisensory facilitation and provide the first demonstration of a relationship between anatomical connectivity and multisensory processing in typically developed individuals. Using a whole-brain analysis and contrasting anatomical models of multisensory processing we found that increased connectivity between parietal regions and early sensory areas was associated with the facilitation of reaction times to multisensory (auditory-visual) stimuli. Furthermore, building on prior animal work suggesting the involvement of the superior colliculus in this process, using probabilistic tractography we determined that the strongest cortical projection area connected with the superior colliculus includes the region of connectivity implicated in our independent whole-brain analysis.
The dependence of the distortion product 2f1- f2 on primary levels in non-impaired human ears

The optimal intensity relation between the two primaries used to generate Distortion Product Otoacoustic Emissions (DPOAEs) in unimpaired human ears, over a clinically relevant intensity range, was...
Social Outcomes Associated With Media Viewing Habits of Low-Income Preschool Children

Research Findings: The purpose of this study was to examine the relationship between preschool children's social outcomes in the classroom (including hyperactivity, aggression, and social skills) and their media viewing habits (including the amount of television they watch and whether they watch videos/movies that are rated as inappropriate for young children). The participants were 92 low-income pre-kindergarten-age children for whom we obtained parent reports of media viewing habits and teacher reports of classroom behavior. The results suggested that viewing of inappropriate content was associated with higher hyperactivity and aggression scores and a lower social skills rating, whereas the amount of viewing was not related to these classroom outcomes. Policy: There has been a great deal of focus on how both the amount and content of television viewed affects social development in middle and later childhood. These studies have helped influence the development of guidelines for parents of young children ...
Structural Factors in the In Vivo Chelate Mobilization of Aged Cadmium Deposits

The role of structural factors in determining the relative efficacy of dithiocarbamates as chelating agents for the in vivo mobilization of aged cadmium deposits is examined for 23 newly synthesized compounds of this type. The critical feature in determining the efficacy of the compounds in mobilizing intracellular cadmium is the balance between hydrophobic and hydrophilic groups. This balance also governs the other properties of these compounds such as the organ specificity of action and the relative propensity to carry cadmium to the brain. The transport of cadmium to the brain by dithiocarbamate can be greatly reduced by the incorporation of appropriate hydrophilic groups that prevent the formation of lipid-soluble cadmium complexes that pass readily into the brain. If the chelating agents carry an additional ionic charge, their ability to pass through cellular membranes and react with intracellular deposits of cadmium is significantly reduced, with other structural factors being equal. The structural features that optimize mobilization of cadmium from the kidney do not appear to be identical with those that optimize its mobilization from the liver. The correlation of cadmiummobilizing properties of these chelating agents with the sum of the Hansch pi constants for the parts of the molecular structures other than the dithiocarbamate grouping (sigma pi) is reasonably good for the removal of renal cadmium by derivatives of D-glucamine and D-xylamine. Another aspect of the molecular structure that appears to play a role is the presence of uncharged polar groups having the ability to form hydrogen bonds. The relevance of these factors in designing chelating agents to enhance the excretion of other toxic metals from their intracellular sites is discussed.
The design of an adaptive agent driven search system for empowering disenfranchised users

This research is about designing and testing a usable, adaptive search system for disenfranchised users. It involves developing the adaptive agent model and architecture for the tool as well as researching its effectiveness for the users. The potential users for this system are not only naive about computer driven technology but are also inhibited to try one, which is a consequence of digital divide. They have not experienced a technology-driven environment where computer has become just another tool to mechanize the daily lives. In this respect they are disenfranchised and they belong to the segment that falls under Poor America. Naturally, handing over another search system will not bridge the divide or empower the disenfranchised users. In order to help them overcome the inhibition, this tool has to be, at the very least, easy to use. Therefore as part of the solution, an adaptive, agent-driven search system is being developed. The system will adapt and personalize the process of search to support individual goals and social needs.
New versatile plasmid vectors for expression of hybrid proteins coded by a cloned gene fused to lacA gene sequences encoding an enzymatically active carboxy-terminal portion of β-galactosidase

A new class of plasmid cloning vectors has been constructed with cleavage sites in a variety of translational reading phases of the promotorless lacZ gene. Fused hybrid proteins can be produced by these vectors by cloning DNA fragments containing the promoter, translation initiation site, and the amino terminal portion of a gene, all with proper orientation, into the correct translational reading frame of the lacZ gene. Enzymatically active hybrid-beta-galactosidase proteins are formed, which have amino-terminal amino acids encoded by the cloned gene segment. Another class of these vectors retains an active lac promoter and lacZ translation-initiation region, which can direct hybrid protein synthesis from DNA fragments that do not have gene initiation regions. These vectors allow transcription from the lacZ initiation region to proceed across, or to stop and restart within, an inserted fragment into the essential part of the beta-galactosidase gene. Also described is a small lacZ gene fragment (cartridge), without a plasmid replicon and without any other lac genes, which can be inserted directly into other genes to form hybrid protein fusions. Polyrestriction site sequences were easily moved into some of these vectors by incorporating drug-resistance genes that serve as markers for the selection and detection of these sequences; those markers can be easily removed afterwards.
DJ-1 knock-down in astrocytes impairs astrocyte-mediated neuroprotection against rotenone

Mutations that eliminate DJ-1 expression cause a familial form of Parkinson's disease (PD). In sporadic PD, and many other neurodegenerative diseases, reactive astrocytes over-express DJ-1 whereas neurons maintain its expression at non-disease levels. Since DJ-1 has neuroprotective properties, and since astrocytes are known to support and protect neurons, DJ-1 over-expression in reactive astrocytes may reflect an attempt by these cells to protect themselves and surrounding neurons against disease progression. We used neuron-astrocyte contact and non-contact co-cultures to show that DJ-1 knock-down in astrocytes impaired their neuroprotective capacity, relative to wild-type astrocytes, against the neurotoxin rotenone. Conversely, DJ-1 over-expression in astrocytes augmented their neuroprotective capacity. Experiments using astrocyte conditioned media on neuron-only cultures suggested that astrocyte-released, soluble factors were involved in the DJ-1-dependent, astrocyte-mediated neuroprotective mechanism. Our findings support the developing view that astrocytic dysfunction, in addition to neuronal dysfunction, may contribute to the progression of a variety of neurodegenerative disorders.
Economic Evaluation of a Disease Management Program for Chronic Obstructive Pulmonary Disease

Background: The data on cost savings with disease management (DM) in chronic obstructive pulmonary disease (COPD) is limited. A multicomponent DM program in COPD has recently shown in a large rando...
Partial Caries Excavation

Regular readers will note that we depart from our normal Critical Appraisal format in this issue of the Journal. This particular Critical Appraisal resembles an expanded Contemporary Issues feature and describes a protocol for partial caries excavation that was recently implemented in the student clinics of the University of North Carolina (UNC) School of Dentistry.
Characterization of the 1B-type ω-gliadins from Triticum aestivum cultivar Butte.

ABSTRACT ω-Gliadins were purified from wheat (Triticum aestivum L. ‘Butte’) flour and characterized. Although reversed-phase HPLC (RP-HPLC) separated the 1B-encoded ω-gliadins into two fractions, 1B1 and 1B2, these fractions had nearly identical amino acid compositions, three similar protein bands in SDS-PAGE, 10 similar spots in two-dimensional PAGE, and two similar N-terminal amino acid sequences. The main components had a range in mass of 48,900–51,500 when estimated by mass spectrometry, significantly less than the mass estimated by SDS-PAGE. The 1B fractions were digested with thermolysin, the peptides were separated by RP-HPLC, the peptide mass was determined, and nine peptides from each fraction were sequenced with nearly identical results for the 1B1 and 1B2 digests. A possible consensus sequence of the 1B-encoded ω-gliadin internal repeat was QQQXP, where X was F, I, or L in descending order of occurrence. The 1D-encoded ω-gliadins were purified by RP-HPLC as a single fraction that had one band i...
Neurotensin and cholecystokinin contract gallbladder circular muscle in chickens.

ABSTRACT The contractile effects of neurotensin (NT) and cholecystokinin octapeptide (CCK-8) on isolated circular smooth muscle strips of chicken gallbladder were investigated. The NT (0.25–300 nM) produced concentration-dependent contractions on smooth muscle with an EC50 of 8.5 nM (95% confidence limits = 5.3–13.6 nM). In comparison, CCK-8 produced concentration-dependent contractions with an EC50 of 13 nM (95% confidence limits of 9–20 nM). There were no statistical differences in contractile responses when comparing NT and CCK-8 at equimolar concentrations. The NT appears to act directly on smooth muscle tissue in the chicken; the contractile responses were not blocked by 10 µM atropine or tetrodotoxin. A portion of the activity is mediated by extracellular calcium as 100 nM nifedipine inhibited 30% of peptide-induced muscle tension. The NT receptor (NTR) type 1 antagonist SR 48692 (0.1 µM) did not significantly reduce NT potency. The contractile effects of CCK-8 remained unaltered in tissues pretreated with atropine, TTX, or nifedipine. The CCK-A antagonist lorglumide, at a concentration of 1 µM, reduced the contractile potency of CCK-8 by one-half. Avian receptors for NT and CCK may differ pharmacologically from their mammalian counterparts, but their contractile actions on the gallbladder resulting in increased biliary output by flow are further evidence of their role in the postprandial regulation of lipid digestion in chickens.
Selection of Characters for an Adansonian Analysis of Mycobacterial Taxonomy

Tests which are most frequently employed to provide characters for numerical analysis of bacterial taxonomy provide little differentiation among the slow-growing members of the genus Mycobacterium. A special scheme was proposed to deal with this problem. Characters were based, to some extent, on quantitative reactions to tests, and were defined, for each test, in terms of natural clustering behavior of a large collection of assorted strains. Inter- and intrataxon analyses were based on comparisons of reaction patterns with tentative hypothetical median strain patterns. This permitted the analysis of larger numbers of cultures than can be practically studied in a conventional n × n table.
A Clustering Approach to Compare Cloud Model Simulations to Satellite Observations

AbstractCloud-resolving models (CRMs) offer an important pathway to interpret satellite observations of microphysical properties of storms. High-frequency microwave brightness temperatures (Tbs) respond to precipitating-sized ice particles and can therefore be compared with simulated Tbs at the same frequencies. By clustering the Tb vectors at these frequencies, the scene can be classified into distinct microphysical regimes (in other words, cloud types). A convective storm over the Amazon observed by the Tropical Rainfall Measuring Mission (TRMM) is simulated using the Regional Atmospheric Modeling System (RAMS) in a semi-ideal setting, and four regimes are defined within the scene using cluster analysis: the “clear sky/thin cirrus” cluster, the “cloudy” cluster, the “stratiform anvil” cluster, and the “convective” cluster. Cluster-by-cluster comparisons between the observations and the simulations disclose biases in the model that are consistent with an overproduction of supercooled water and an excess ...
Sea-surface temperature estimates in the Southeast Pacific based on planktonic foraminiferal species; modern calibration and Last Glacial Maximum

Abstract Estimates of sea-surface temperatures based on foraminiferal faunal species suggest that the Eastern Equatorial Pacific Ocean was 3–5°C cooler during the Last Glacial Maximum (LGM) than at present. Analysis of new cores from the Southeast Pacific reveals a likely source of ice-age cooling in variations of the Peru Current. Off southern Peru, LGM ocean temperatures were 6–8°C cooler than at present, consistent with substantial cooling on land inferred from regional glacier advances and ice-core data. In the Southeast Pacific, ice-age foraminiferal assemblages have good modern analogs, and transfer functions that define assemblages based on ancient samples yield results similar to those based on coretop samples. During the LGM, subpolar species dominate the Eastern Boundary Current off Peru and extend to the equator. In contrast, the range of the equatorial upwelling species remains roughly constant. We infer from these data and a heat budget model that equatorward advection of cool water, more than equatorial upwelling, drove LGM cooling of the Eastern Tropical Pacific Ocean.
The text of Aldhelm's Enigma no. c in Oxford, Bodleian Library, Rawlinson C. 697 and Exeter Riddle 40

Exeter Riddle 40 presents two related problems as a translation of one of Aldhelm's Enigmata (no. c: ‘Creatura’): its dislocation, in an otherwise accurate translation, of six lines from their position in the Latin text; and its connection with the so-called ‘Lorica’ of Leiden, Bibliotheek der Rijksuniversiteit, Voss. lat. Q. 106, the only other surviving Old English translation of an Aldhelmian enigma. In his edition of the Exeter Riddles, Tupper addressed these problems by postulating that both Old English riddles were the work of one translator and that Exeter Riddle 40 was revised from an earlier version of Aldhelm's enigma now lost to us. Although Tupper's view has been widely accepted, it presents a number of difficulties. It is the purpose of the present article to suggest an alternate interpretation of the evidence: that Exeter Riddle 40 – a much later poem than the ‘Leiden Riddle’, a Northumbrian poem perhaps of the eighth century – was translated from a ninth-century continental manuscript with tenth-century English corrections: Oxford, Bodleian Library, Rawlinson C. 697.
Staying rich: LTI systems which preserve signal richness

There are many ways to define richness of a discrete time signal. This paper considers a particular definition and explores the conditions under which a linear time invariant system preserves the richness property. Several examples are presented to clarify the issues involved in the problem. Some sufficient conditions are presented. Also presented are necessary and sufficient conditions for some special cases. A set of necessary and sufficient conditions for the most general case is not known at this time.
Impact of negatively charged patches on the surface of MHC class II antigen-presenting proteins on risk of chronic beryllium disease.

Chronic beryllium disease (CBD) is a granulomatous lung disease that occurs primarily in workers who are exposed to beryllium dust or fumes. Although exposure to beryllium is a necessary factor in the pathobiology of CBD, alleles that code for a glutamic acid residue at the 69th position of the HLA-DPβ1 gene have previously been found to be associated with CBD. To date, 43 HLA-DPβ1 alleles that code for glutamic acid 69 (E69) have been described. Whether all of these E69 coding alleles convey equal risk of CBD is unknown. The present study demonstrates that, on the one hand, E69 alleloforms of major histocompatibility complex class II antigen-presenting proteins with the greatest negative surface charge convey the highest risk of CBD, and on the other hand, irrespective of allele, they convey equal risk of beryllium sensitization (BeS). In addition, the data suggest that the same alleles that cause the greatest risk of CBD are also important for the progression from BeS to CBD. Alleles convey the highest risk code for E26 in a constant region and for E69, aspartic acid 55 (D55), E56, D84 and E85 in hypervariable regions of the HLA-DPβ1 chain. Together with the calculated high binding affinities for beryllium, these results suggest that an adverse immune response, leading to CBD, is triggered by chemically specific metal–protein interactions.
On Constructive Multi-Source Network Coding

The multi-source network coding problem, where multiple multicast sessions with independent data share a network, is an open challenge. It is observed that random mixing is asymptotically optimal for a pollution-free multi-source network coding problem, where no receiver can be reached by a source it does not need. To handle pollution in a general network, a pollution-free network of tagged pipes is constructed. Each link is partitioned into tagged pipes; each tag is a subset of the sources. The content flowing in each pipe can only be a function of the sources indicated in the tag. The pipes are interconnected to form a pollution-free network. This constructive scheme gives rise to an achievability theorem for general multi-source network coding. For acyclic graphs, the fact that decoded information can be used in generating output is modelled via "helpers". This results in a stronger achievability theorem for acyclic graphs. Further incorporating the degree of freedom in adding receivers, an even stronger achievability theorem is derived.
The Clathrin Adaptor Complex Responsible for Somatodendritic Protein Sorting

Neuronal proteins contain "address labels" that govern their localization. In this issue of Neuron, Farias et al. (2012) identify the machinery that recognizes one class of dendritic localization signals and establish its role in the polarization of dendritic proteins, including several postsynaptic receptors.
Procoagulant and plasminogen activator activities of bronchoalveolar fluid in patients with pulmonary sarcoidosis.

Tissue fibrin deposition may be an important component of inflammatory reactions. Current evidence suggests that intraalveolar procoagulant (PC) and plasminogen activator (PA) activities may be important determinants of local fibrin turnover in lung injury. In this study, we measured the PC and PA activities in cell-free bronchoalveolar lavage fluid (BALF) obtained from 17 patients with pulmonary sarcoidosis and 12 normal volunteers. Procoagulant activity was assayed by timing clot formation in a one-stage coagulation assay, and plasminogen activator activity was determined by measuring plasminogen-dependent lysis of [125I]fibrin. Mean PC activity in the sarcoidosis group was significantly elevated (102 ± 25 versus 31.5 ± 8.1 tissue thromboplastin units/ml; p < 0.002), with 6 of 17 patient values beyond the 95% confidence limits of normals. These differences were not seen when PC activity was corrected for total protein in BAL. In contrast, PA activity tended to be lower in the sarcoidosis group (0.54 ± 0...
Should intrathecal lidocaine be used in the 21st century

Hyperbaric 5% lidocaine has been available for intrathecal use since 1954. The initial studies concluded that it was a safe drug for short procedures. Recently, the use of this drug for spinal anesthesia has been questioned. There were cases of cauda equina syndrome following its use for continuous spinal anesthesia. Following these occurrences, it was felt that lidocaine should not be used for continuous spinal anesthesia, rather for single-shot spinal anesthesia only. Intense follow-up of patients receiving intrathecal lidocaine for single-shot spinal anesthesia revealed a higher incidence of back pain radiating to the thighs and legs as compared to other drugs or general anesthesia. Although these symptoms have been linked to the drug, there were other factors affecting the incidence. Lithotomy position was a more significant predictor for developing these symptoms. Furthermore, there are seven cases of cauda equina syndrome following single-shot hyperbaric lidocaine. Cauda equina syndrome is a permanent disability. It occurred in patients of varying ages and with doses ranging from 60 mg to 120 mg. There are safe alternatives to lidocaine for outpatient spinal anesthesia, such as bupivacaine, prilocaine, or mepivacaine. These drugs have a lower incidence of transient neurologic symptoms and do not delay discharge. Given the possibility of permanent neurologic injury and given that safe alternatives exist, one has to question whether intrathecal lidocaine should still be used in the 21st century.
Seroprevalence of Canine Leishmaniasis and American Trypanosomiasis in Dogs From Grenada, West Indies

Abstract Canine leishmaniasis and American trypanosomiasis (AT) are caused by related hemoflagellated parasites, Leishmania spp. and Trypanosoma cruzi, which share several common host species. Dogs are reservoirs for human infections by both pathogens. We determined the prevalence of antibodies to Leishmania spp. and T. cruzi in dogs from Grenada, West Indies. We examined 70 dog sera using the qualitative immunochromatographic dipstick tests (ICTs) based on recombinant antigens specific for visceral leishmaniasis and AT. Antibodies to visceral Leishmania were not detected in Grenadian dogs by ICT. Using the canine dipsticks for AT, antibodies to T. cruzi were determined in 3 (4.3%) of the 70 dogs. Results from this study indicate that dogs in Grenada are exposed in low levels to T. cruzi, but not to visceral Leishmania spp. at all.