cssi/SciSciGPT-SciSciNet huggingface dataset:
Plasmonic local heating beyond diffraction limit by the excitation of magnetic polariton

In recent years, optical local heating in the nanoscale has attracted great attention due to its unique features of small hot spot size and high energy density. Plasmonic local heating can provide solutions to several challenges in data storage and cancer treatment. Research conducted in this field to achieve plasmonic local heating has mainly utilized the excitation of localized surface plasmon (LSP) or surface plasmon resonance (SPR). However, achieving plasmonic local heating by the excitation of magnetic polariton (MP) has not been researched extensively yet. We numerically investigate the optical response of a nanostructure composed of a gold nanowire on a gold surface separated by a polymer spacer using the ANSYS High Frequency Structural Simulator (HFSS). The structure exhibits a strong absorption peak at the wavelength of 750 nm, and the underlying physical mechanism is verified by the local electromagnetic field distribution to be the magnetic resonance excitation. By incorporating the volume loss density due to the strong local optical energy confinement as the heat generation, nanoscale temperature distribution within the structure is numerically obtained with a thermal solver after assigning proper boundary conditions. The results show a maximum temperature of 158.5°C confined in a local area on the order of 35 nm within the ultrathin polymer layer, which clearly demonstrates the plasmonic local heating effect beyond diffraction limit by excitation of MP.
The palindromic series I repeats in the simian cytomegalovirus major immediate-early promoter behave as both strong basal enhancers and cyclic AMP response elements.

Abstract A 600-base-pair (bp) enhancer region upstream from the major IE94 gene of simian cytomegalovirus (SCMV) produces very strong basal expression of associated gene products. This domain consists of multiple sets of interspersed repetitive elements, including 11 copies of a conserved 16-bp palindromic sequence with the consensus CCATTGACGTCAATGG. These series I repeats contain an 8-bp core TGACGTCA that resembles the cyclic AMP (cAMP) response element (CRE) of cellular genes. In transient chloramphenicol acetyltransferase assays in K562 human erythroleukemia cells, a set of deleted variants of the IE94 promoter all responded up to 15-fold to induction by cAMP. However, successive removal of most of the SCMV 16-bp motifs reduced basal expression over 20-fold. The cAMP stimulation was also manifested at the steady-state RNA level after SCMV infection of K562 cells and was detectable within 1.5 h after treatment of DNA-transfected cells. Addition of a single 30-bp oligonucleotide encompassing the 16-bp palindrome conveyed up to 10-fold cAMP responsiveness onto a heterologous weak promoter but had no effect on basal expression. In contrast, two or more adjacent copies produced 20- to 40-fold increases in basal expression and provided greater than 200-fold activation in the presence of cAMP. Similar effects were obtained when the oligonucleotides were placed in a downstream location relative to the reporter gene. Studies with mutant oligonucleotides revealed that both the core CRE and the flanking sequence portions of the 16-bp elements were essential for enhancer function. Both components were also important for maximum cAMP responsiveness. Band shift assays with fractionated nuclear extracts from Raji lymphocytes revealed multiple competable complexes with cellular DNA-binding factors that recognized the series I elements. Three distinct CREB-like factors were detected that required only the core 8-bp elements for binding. We conclude that the 16-bp series I repeats provide a major contribution to the constitutive enhancer properties of the IE94 promoter and also act as functional CREs. The cAMP response properties appear likely to play a key role in reactivation of the virus from a latent state in appropriately differentiating cell types.
Generation and stabilization of whey-based monodisperse nanoemulsions using ultra-high-pressure homogenization and small amphipathic co-emulsifier combinations.

Ultra-high-pressure homogenization (UHPH) was used to generate monodisperse stable peanut oil nanoemulsions within a desired nanosize range (<100 nm) (DNR) stabilized using combinations of whey protein concentrate (WPC), sodium dodecyl sulfate, Triton X-100 (X100), and zwitterionic sulfobetaine-based surfactants differing in hydrophobicity. For WPC [2.0% (w/v)], the dispersed-phase fractions (φ) of 0.05 and 210 MPa significantly reduced the mean globule size (dvs) but the grouped frequency distribution was bimodal and larger than that of DNR. Addition of co-emulsifier sulfobetaine 3-10 (SB3-10) [7.5% (w/w) WPC] gave particles within DNR (dvs of 73 nm) though still in a bimodal distribution. Circular dichroism prior to UHPH showed little disruption of the secondary structure of proteins in WPC by SB3-10, whereas X100 obliterated it. A WPC/SB3-10 mixture retained some periodic structure even when mixed with X100 [10% (w/w) WPC] and remarkably gave a narrow monomodal distribution within DNR with the highest ...
Rationally evolving tRNAPyl for efficient incorporation of noncanonical amino acids

Genetic encoding of noncanonical amino acids (ncAAs) into proteins is a powerful approach to study protein functions. Pyrrolysyl-tRNA synthetase (PylRS), a polyspecific aminoacyl-tRNA synthetase in wide use, has facilitated incorporation of a large number of different ncAAs into proteins to date. To make this process more efficient, we rationally evolved tRNA(Pyl) to create tRNA(Pyl-opt) with six nucleotide changes. This improved tRNA was tested as substrate for wild-type PylRS as well as three characterized PylRS variants (N(ϵ)-acetyllysyl-tRNA synthetase [AcKRS], 3-iodo-phenylalanyl-tRNA synthetase [IFRS], a broad specific PylRS variant [PylRS-AA]) to incorporate ncAAs at UAG codons in super-folder green fluorescence protein (sfGFP). tRNA(Pyl-opt) facilitated a 5-fold increase in AcK incorporation into two positions of sfGFP simultaneously. In addition, AcK incorporation into two target proteins (Escherichia coli malate dehydrogenase and human histone H3) caused homogenous acetylation at multiple lysine residues in high yield. Using tRNA(Pyl-opt) with PylRS and various PylRS variants facilitated efficient incorporation of six other ncAAs into sfGFP. Kinetic analyses revealed that the mutations in tRNA(Pyl-opt) had no significant effect on the catalytic efficiency and substrate binding of PylRS enzymes. Thus tRNA(Pyl-opt) should be an excellent replacement of wild-type tRNA(Pyl) for future ncAA incorporation by PylRS enzymes.
An unorthodox bacteriophytochrome from Rhodobacter sphaeroides involved in turnover of the second messenger c-di-GMP

Bacteriophytochromes are bacterial photoreceptors that sense red/far red light using the biliverdin chromophore. Most bacteriophytochromes work as photoactivated protein kinases. The Rhodobacter sphaeroides bacteriophytochrome BphG1 is unconventional in that it has GGDEF and EAL output domains, which are involved, respectively, in synthesis (diguanylate cyclase) and degradation (phosphodiesterase) of the bacterial second messenger c-di-GMP. The GGDEF-EAL proteins studied to date displayed either diguanylate cyclase or phosphodiesterase activity but not both. To elucidate the function of BphG1, the holoprotein was purified from an Escherichia coli overexpression system designed to produce biliverdin. The holoprotein contained covalently bound biliverdin and interconverted between the red (dark) and far red (light-activated) forms. BphG1 had c-di-GMP-specific phosphodiesterase activity. Unexpectedly for a photochromic protein, this activity was essentially light-independent. BphG1 expressed in E. coli was found to undergo partial cleavage into two species. The smaller species was identified as the EAL domain of BphG1. It possessed c-di-GMP phosphodiesterase activity. Surprisingly, the larger species lacking EAL possessed diguanylate cyclase activity, which was dependent on biliverdin and strongly activated by light. BphG1 therefore is the first phytochrome with a non-kinase photoactivated enzymatic activity. This shows that the photosensory modules of phytochromes can transmit light signals to various outputs. BphG1 is potentially the first "bifunctional" enzyme capable of both c-di-GMP synthesis and hydrolysis. A model for the regulation of the "opposite" activities of BphG1 is presented.
Vasopressin deficiency and blood glucose interactions on passive avoidance behavior

The performance of a passive avoidance task (measured for two trials based upon number of complete step-downs and latency to respond) and blood glucose levels were examined in five groups of animals. The groups included vasopressin-deficient (DI) and vasopressin-containing (LE) rats under ad lib (AL) and food-restricted (FR) conditions, as well as DI-FR animals provided with access to an 8% sucrose solution (SUC). In the AL condition, no significant differences were found between DI and LE animals in either step-down occurrences or blood glucose levels. However, the DI animals were significantly slower in latency to respond in trial 1. With FR, the LE animals resembled the LE-AL animals in both passive avoidance behavior and blood glucose levels. The DI-FR animals that were not provided with SUC showed an impairment in passive avoidance behavior and low blood glucose levels, whereas DI-FR animals provided with SUC showed an amelioration of passive avoidance deficiencies and had blood glucose levels comparable to AL animals and LE-FR animals. On trial 2, a significant negative correlation was found between number of step-down occurrences and blood glucose levels, and a significant positive correlation was found between latency to respond and blood glucose levels.(ABSTRACT TRUNCATED AT 250 WORDS)
Examining the relationship between the therapeutic bond and the phases of treatment outcome.

This study examined the associationbetween the therapeutic bond—anelement of the therapeutic alliance—andtreatment effectiveness. Psychotherapyclients (n = 114) completed self-reportquestionnaires at intake and throughoutopen-ended, psychodynamically orientedpsychotherapy. Three bond scales, roleinvestment (RI), empathic resonance(ER), and mutual affirmation (MA), werecontrasted to session quality and thethree phases of outcome (remoralization,remediation, and rehabilitation). Resultsindicated that different aspects of thebond predicted session quality andtreatment outcome. Clients who feltmotivated and invested in therapy(relatively high RI) and who reported thatthe therapeutic environment was friendlyand affirmative (relatively high MA) werelikely to rate the session as being helpfuland productive. Clients who had arelatively high sense of understandingand of being understood (ER)experienced greater remoralization andremediation (but not rehabilitation). Theresults are placed within the context ofrecent research into the therapeuticalliance.
Gas-mediated vitreous compression: an experimental alternative to mechanized vitrectomy

We have developed a simple technique in rabbit and baboon eyes that utilizes intravitreally injected perfluoropropane gas, which expands slowly to efficiently compress and displace nearly completely the vitreous body. There is cataract formation after extended contact of the gas bubble with the lens. However, it is rapidly reversible by reducing the duration of lens contact (gas-fluid exchange) and by using young animals. No long-term alterations in intraocular pressure or retinal function were observed, as determined by electroretinography, during the 4-month test period.
Beyond ethanol: a techno‐economic analysis of an integrated corn biorefinery for the production of hydrocarbon fuels and chemicals

Dried distillers grains with solubles (DDGS) are potential feedstocks for the production of hydrocarbon fuels and chemicals from catalytic pyrolysis. This study evaluates the economic feasibility of a 2000-metric-ton-corn-per-day integrated biorefinery with an add-on facility processing corn DDGS to hydrocarbons. In addition to ethanol, the integrated facility would produce a wide range of hydrocarbons, including aromatics, olefins, and synthetic gasoline and diesel. The hydrocarbon products command a substantially higher market value than that of the pre-processed DDGS: $109 million per year vs. $78 million per year. The add-on DDGS conversion facility contributes an extra $152 million of capital investment compared with the stand-alone corn ethanol production scenario. The operating costs for the integrated scenario are also higher than for the stand-alone scenario, mainly due to increases in utilities, labor costs, and capital depreciation. The minimum fuel selling price (MFSP) for the integrated scenario is $2.27/gallon, which is comparable to the MFSP of $2.18/gallon for the stand-alone scenario. Sensitivity analysis shows that the feedstock cost, hydrocarbon yield, and fixed capital investment have the greatest impacts on the MFSP. With the benefit of products diversity, the proposed integrated corn biorefinery may be competitive with conventional stand-alone ethanol production. © 2014 Society of Chemical Industry and John Wiley & Sons, Ltd
Sustained Competitive Advantage and Organizational Inertia: The Cost Perspective of Knowledge Management

Sustained competitive advantage and organizational adaptation have been the most commonly used perspectives in organizational performance studies. However, from the cost perspective of knowledge management, organizations seeking a sustained competitive advantage by constructing specific knowledge may result in structural inertia. Thus, a contradiction occurs between the perspectives of sustained competitive advantage and organizational adaptation. This article presents the argument of such a contradiction and proposes a feasible solution.
Optimal dynamic embedding of X-trees into arrays

Abstract We present a dynamic embedding of the contents of a storage medium organized as an X-tree into a storage medium organized as a d -dimensional array. Let X be a multihead bounded activity machine with a single storage tape organized as an X-tree. A multihead bounded activity machine D with a single tape organized as a d -dimensional array is used to simulate X on-line. If X runs in time t ( n ) on inputs of length n , then D simulates X in time O(t(n) 1+1 d log t(n)) . Furthermore, this simulation is optimal.
On the privacy-cost tradeoff of an in-home power storage mechanism

Demand response systems in the electricity grid, which rely on two way communication between the consumers and utility, requires the transmission of instantaneous energy consumption to utilities. Perfect knowledge of a users' power consumption profile by a utility is a violation of privacy and can be detrimental to the successful implementation of demand response systems. An in-home storage system, which provides a viable means to achieve the cost savings of instantaneous electricity pricing without the inconvenience (delay) caused by demand response, can also be used to maintain the privacy of a user's power profile. In this work, the design of battery charging and discharging algorithms in response to time varying demand and prices are studied. In particular, a fundamental tradeoff between how much privacy can be provided to individual consumers by a finite capacity battery and the cost savings that can be achieved assuming a zero tolerance for delay is studied using a Markov process model for user's demands and instantaneous electricity prices. When the demands and prices follow a Markovian evolution, the optimization problem is shown to be equivalent to a Partially Observable Markov Decision Process with belief dependent rewards (ρ-POMDP). Due to high computational complexity of the model, computable inner and upper bounds are presented on the optimal tradeoff. In particular, inner bounds are derived using specific strategies for battery scheduling including the cost optimal, optimal fixed deterministic strategy and the greedy algorithm. Upper bounds are provided using a standard rate-distortion optimization. These bounds are derived for a binary model, where the battery state is binary, and the demand and prices are distributed i.i.d. Bernoulli.
Time warping of evolutionary distant temporal gene expression data based on noise suppression.

Background Comparative analysis of genome wide temporal gene expression data has a broad potential area of application, including evolutionary biology, developmental biology, and medicine. However, at large evolutionary distances, the construction of global alignments and the consequent comparison of the time-series data are difficult. The main reason is the accumulation of variability in expression profiles of orthologous genes, in the course of evolution.
A "Reverse burst" active site titration procedure for human carbonic anhydrase B.

Abstract Between pH 7 and pH 10.5, p-nitrophenyl p -sulfamyl benzoate (PNP-SAB) binds very strongly to human carbonic anhydrase B (dissociation constant on the order of 10−9 M or less at pH 7.5), but is not hydrolyzed by the enzyme. Because the binding is essentially stoichiometric under readily accessible conditions, this ester may be used as an active site titrant, by measuring the rapid hydrolysis of excess unbound PNP-SAB catalyzed by an added nucleophile (“reverse burst”).
Singlet Excited State Dynamics of Tetrakis(4-N-methylpyridyl)porphine Associated with DNA Nucleotides

The singlet excited state behavior of tetrakis(4-N-methylpyridyl)porphine (T4MPyP) in the presence of the four mononucleotides of DNA in aqueous solution has been examined. Addition of the nucleotides of adenine, thymine, or cytosine to a solution containing T4MPyP results in an increase in the fluorescence intensity of the porphyrin, while addition of guanine substantially quenches the intensity. Optical absorption measurements demonstrate noncovalent interactions of the nucleotides with the porphyrin, resulting in bathochromic shifts in the Soret region. Binding constants for the base:porphyrin complexes were determined from steady-state absorption data to be 1743 ± 68, 385 ± 15, 2433 ± 150, and 198 ± 7 M-1 for dAMP, dTMP, dGMP, and dCMP, respectively. The T4MPyP singlet state lifetime increases from 5.29 to 11.3, 10.3, and 7.8 ns in the presence of dAMP, dTMP, and dCMP, respectively. In the case of dGMP, the lifetime data was best fit to a Lorentzian distribution centered at 0.69 ns and a discrete comp...
Bond-Valence Constraints on Liquid Water Structure

The recent controversy about the structure of liquid water pits a new model involving water molecules in relatively stable rings-and-chains structures against the standard model that posits water molecules in distorted tetrahedral coordination. Molecular dynamics (MD) simulations—both classical and ab initio—almost uniformly support the standard model, but since none of them can yet reproduce all the anomalous properties of water, they leave room for doubt. We argue that it is possible to evaluate these simulations by testing them against their adherence to the bond-valence model, a well known, and quantitatively accurate, empirical summary of the behavior of atoms in the bonded networks of inorganic solids. Here we use the results of ab initio molecular dynamics simulations of ice, water, and several solvated aqueous species to show that the valence sum rule (the first axiom of the bond-valence model,) is followed in both solid and liquid bond networks. We then test MD simulations of water, employing several popular potential models, against this criterion and the experimental O-O radial distribution function. It appears that most of those tested cannot satisfy both criteria well, except TIP4P and TIP5P. If the valence sum rule really can be applied to simulated liquid structures, then itmore » follows that the bonding behaviors of atoms in liquids are in some ways identical to those in solids. We support this interpretation by showing that the simulations produce O-H…O geometries completely consistent with the range of geometries available in solids, and the distributions of instantaneous valence sums reaching the atoms in both the ice and liquid water simulations are essentially identical. Taken together, this is powerful evidence in favor of the standard distorted tetrahedral model of liquid water structure.« less
Determination of the anisotropy of surface energy of metals—I: Theoretical analysis

Abstract Potentially, one of the most sensitive techniques for experimentally determining the orientation dependence of the surface tension of f.c.c. metals is the study of the grooving behavior at the intersections of twin boundaries with the external surface of the solid. The usefulness of the technique has been limited, however, by the type of analysis used in the past in treating the data. This paper presents a new analysis of this problem which requires none of the restrictive assumptions previously used. The approach is interpolative in nature and provides for a mathematically consistent treatment of the data. Several possible modifications of the analysis are also presented to demonstrate the generality of the approach to problems of this nature and to indicate the statistical significance of the solution.
A general description of the Telstar spacecraft

The Telstar spacecraft design is discussed with emphasis on the electronics system. The description includes early planning, starting with frequency allocation considerations, and carries the program through electrical and mechanical design, construction and evaluation of the electronics system. The content is aimed at a broad introduction, depending on companion papers for many details of the spacecraft design.
Heat-Transport Mechanisms in Superlattices

The heat transport mechanisms in superlattices are identified from the cross-plane thermal conductivity Λ of (AlN)x–(GaN)y superlattices measured by time-domain thermoreflectance. For (AlN)4.1 nm–(GaN)55 nm superlattices grown under different conditions, Λ varies by a factor of two; this is attributed to differences in the roughness of the AlN/GaN interfaces. Under the growth condition that gives the lowest Λ, Λ of (AlN)4 nm–(GaN)y superlattices decreases monotonically as y decreases, Λ = 6.35 W m−1 K−1 at y = 2.2 nm, 35 times smaller than Λ of bulk GaN. For long-period superlattices (y > 40 nm), the mean thermal conductance G of AlN/GaN interfaces is independent of y, G ≈ 620 MW m−2 K−1. For y < 40 nm, the apparent value of G increases with decreasing y, reaching G ≈ 2 GW m−2 K−1 at y < 3 nm. MeV ion bombardment is used to help determine which phonons are responsible for heat transport in short period superlattices. The thermal conductivity of an (AlN)4.1 nm–(GaN)4.9 nm superlattice irradiated by 2.3 MeV Ar ions to a dose of 2 × 1014 ions cm−2 is reduced by <35%, suggesting that heat transport in these short-period superlattices is dominated by long-wavelength acoustic phonons. Calculations using a Debye-Callaway model and the assumption of a boundary scattering rate that varies with phonon-wavelength successfully capture the temperature, period, and ion-dose dependence of Λ.
Comparison of adhesive bond strength of different cell types in vitro

An established in vitro assay for quantitating cell-substratum adhesion has been utilized to measure the adhesiveness of 10 cell lines to a colloidal overlay. The procedure, a derivation of the William’s blister test for adhesives, involves growing cells to confluency on a polystyrene surface and then overlaying the monolayers with a Bacto-agar substratum. The cell-agar substratum systems are debonded and thera,adhesive bond strength, of the separation of the two interfaces calculated. Thera’s were determined for the following cell types: SGL (gingival epithelial-like), L (transformed mouse fibroblasts), HeLa (human carcinoma), MDCK (canine kidney epithelial), WI-38 (human embryonic lung), Flow 1000 (human embryonic skin—muscle), Flow 4000 (human embryonic kidney), Flow 5000 (whole human embryo), BALB/c 3T3 (mouse fibroblasts) and SV40-transformed BALB/c 3T3 (simian virus 40-transformed mouse fibroblasts). Transformed cells (L, HeLa and SV40-transformed BALB/c 3T3) proved to be quantitatively less adhesive (ra/cell) than either fibroblast or epithelial-like cell lines. Of the “normal” cells tested the kidney cells, human embryonic fibroblast and canine epithelial cells, and the gingival epithelial-like cells demonstrated a weaker binding to the colloidal overlay than the mouse fibroblasts (BALB/c 3T3), the human embryonic lung, the human embryonic skin-muscle, and the whole human embryo fibroblast cell lines. Concanavalin A increased the bonding strength of Flow 5000 cells after 24 hr incubation; however, the adhesiveness of the treated BALB/c 3T3 cells remained similar to the unterested samples while thera of the treated SV40-transformed BALB/c 3T3 cells decreased.
Impact of task experience and individual factors on training-emphasis ratings

This study included 2 sets of analyses examining the impact of task experience and individual factors on task ratings of training emphasis. Aerospace ground equipment mechanics in the U.S. Air Force completed surveys 8 months and 12 months after formal training. Mechanics rated how much formal training they would recommend for a sample of tasks. In the cross-sectional analyses, with tenure constant at 12 months, an individual's breadth of experience (number of tasks performed) and level of self-efficacy were found to have significant effects on training-emphasis ratings. The change analyses examined factors influencing changes in ratings of training emphasis from 8 to 12 months on the job
Tunneling spectroscopy of the Si(111)2 × 1 surface

Abstract Using a scanning tunneling microscope, the tunneling current versus voltage is measured at fixed values of separation between a tungsten probe-tip and a Si(111)2 × 1 surface. Rectification is observed in the I - V curves and is quantitatively accounted for by an electric-field enhancement due to the finite radius-of-curvature of the probe-tip. The parallel wave-vector of certain states is obtained from the decay length of the tunneling current. A rich spectrum is obtained in the ratio of differential to total conductivity, yielding a direct measure of the Si surface density-of-states. Small shifts are observed in the spectrum as a function of doping, and are attributed to shifts in the position of the surface Fermi level.
Improved Harmonic Large-Angle Fuselage Aerodynamics Model

Introduction F LIGHT vehicle simulation, guidance and control law design, and flight performance analysis methods commonly use aerodynamic models based on tabulated force and moment coefficients. Inputs for these models are generally derived from wind-tunnel test data and/or computational fluid dynamics (CFD) results. However, wind-tunnel data are often only available for a limited range of pitch and yaw angles, and CFD computations for a large number of arbitrary attitudes can be expensive. Rotorcraft simulation models require aerodynamic inputs at extreme attitudes and commonly use trigonometric high-angle models to provide smoothly varying data in these regimes.1,2 Other applications for extreme high-angle aerodynamic models are ground-handling simulations, where the wind may come from any azimuth, flight performance analysis at high angles,2 and trajectory analysis of tumbling bodies. This Engineering Note presents a trigonometric, quasi-steady, fuselage aerodynamics model that is valid at all aerodynamic angles with a range of ±180 deg yaw and ±90 deg pitch. This model is based on the C81 high-angle equation (HAE) model found in some rotorcraft simulations1 but with improvements to the usability of the original model. The HAE model uses aerodynamic coefficient inputs at key values of pitch and yaw angles that may come from wind-tunnel tests, CFD analysis, or other sources. A set of sinusoidal functions is used to estimate the values for all six wind-reference fuselage aerodynamic forces and moments at any combination of pitch angle and yaw angle. The HAE model is desirable in that the equations are continuous and easily computed, give the proper trends at all attitudes, include some cross-coupling effects, and require relatively few inputs. The quasi-steady nature of the HAE model makes it unsuitable for situations where time-dependent flow characteristics are significant. This model is not suitable where high accuracy is required and is not expected to capture sudden changes in flow characteristics at critical angles such as the onset of stall or slender forebody vortex shedding. To address this issue, a blending scheme is often used to transition between wind tunnel data (or other high-quality data) at low angles and the HAE model at high angles.1 This Note addresses three limitations with the Ref. 1 model. First, the original model assumes lateral–directional coefficients are con-
Isolation of the microtubule-vesicle motor kinesin from rat liver: Selective inhibition by cholestatic bile acids☆

Abstract Background/Aims: Vesicular transport is supported by microtubule-based, force-transducing adenosine triphosphatases (ATPases), such as kinesin, a ubiquitous motor enzyme that has been well studied in neuronal tissues. Although vesicular transport is important for hepatocellular secretory and clearance activities, the role of kinesin in liver function is poorly understood. Furthermore, the effects of bile acids on kinesin are unknown. Methods: Kinesin was purified from rat liver cytosol by conventional chromatography and microtubule affinity binding and was characterized by immunoblotting with domain-specific kinesin antibodies and amino acid sequencing of tryptic fragments. Kinesin activity was measured with and without bile acids using an in vitro motility assay and ATPase assays. Results: Immunoblot analysis and partial amino acid sequencing of purified kinesin showed that the sequence at the heavy chain of hepatic kinesin is nearly identical to that of brain kinesin. Purified kinesin transported microtubules in vitro with a velocity of ≈0.5 μm/s; this activity was significantly inhibited by 0.5–1 mmol/L taurochenodeoxycholate but not by tauroursodeoxycholate. At a dose of 1 mmol/L, chenodeoxycholate conjugates, but not ursodeoxycholate or cholate conjugates, directly inhibited the ATPase activities of kinesin and another microtubule motor, cytoplasmic dynein. Conclusions: Cholestatic concentrations of chenodeoxycholate conjugates directly inhibit the activity of microtubule motors, suggesting a possible mechanism for impairment of vesicular transport in cholestasis.
Episodic secretion of parathyroid hormone in postmenopausal women: assessment by deconvolution analysis and approximate entropy.

In healthy young subjects, parathyroid hormone (PTH) is secreted presumptively in a dual fashion, with low amplitude pulses apparently superimposed on tonic secretion. In contrast, PTH secretion has not been as well characterized in postmenopausal women, and relationships among bone density, estrogen status, and PTH release have not been explored. It is possible that a pulsatile pattern of PTH secretion is important for bone remodeling, since exogenous PTH administered in a pulsatile manner stimulates bone formation. To assess the importance of pulsatile PTH secretion as a determinant of bone mass, we measured PTH in blood sampled every 2 minutes for 6 h in four groups of older women: (1) high bone density receiving estrogen (n = 6), (2) high bone density not receiving estrogen (n = 5), (3) low bone density receiving estrogen (n = 6), and (4) low bone density not receiving estrogen (n = 8). The plasma PTH release profiles were subjected to deconvolution analysis, which resolves measured hormone concentrations into secretion and clearance components, and to an approximate entropy (ApEn) estimate, which provides an ensemble measure of the serial regularity or orderliness of the release process. In postmenopausal subjects, PTH was secreted in a fashion similar to that observed in young adults, with significant tonic secretion and PTH pulse occurrences averaging every 18–19 minutes. Pulsatile PTH secretion accounted for approximately 25% of the total secreted PTH. There were no differences in the amplitude or frequency of pulsatile PTH secretory parameters or in ApEn values among the four groups or compared with young controls. We conclude that in postmenopausal women, PTH secretory patterns and temporal organization are similar to those in healthy young subjects and are not altered in states of low bone density or estrogen deficiency. This suggests that abnormalities in orderly pulsatile PTH secretion are unlikely to play a major role in established postmenopausal osteoporosis.
Effect of pre-treatment on recrystallization and recrystallization textures of cold rolled CC AA 5182 aluminum alloy

Abstract The effect of pre-treatment on recrystallization and recrystallization textures of cold rolled continuous cast (CC) AA 5182 aluminum alloy as well as on the earing behavior was investigated. The progress of recrystallization was tracked by means of measurements of tensile properties. The texture of cold rolled and annealed samples was determined by X-ray diffraction. The results show that the recrystallization temperature of cold rolled CC AA 5182 aluminum alloy without pre-treatment is about 24 °C higher than that of the alloy with pre-treatment. The recrystallization textures of cold rolled CC AA 5182 aluminum alloy are characterized by the R, cube and Goss orientations. The recrystallization textures of cold rolled CC AA 5182 aluminum alloy without pre-treatment exhibit stronger cube and Goss components and a weaker R component than those of the alloy with pre-treatment. The deformed and recovered samples without pre-treatment possess a significantly higher 45° earing than the samples with pre-treatment, while the recrystallized samples without pre-treatment possess a slightly lower 45° earing than the samples with pre-treatment.
Auditory-Evoked Spike Firing in the Lateral Amygdala and Pavlovian Fear Conditioning: Mnemonic Code or Fear Bias?

Amygdala neuroplasticity has emerged as a candidate substrate for Pavlovian fear memory. By this view, conditional stimulus (CS)-evoked activity represents a mnemonic code that initiates the expression of fear behaviors. However, a fear state may nonassociatively enhance sensory processing, biasing CS-evoked activity in amygdala neurons. Here we describe experiments that dissociate auditory CS-evoked spike firing in the lateral amygdala (LA) and both conditional fear behavior and LA excitability in rats. We found that the expression of conditional freezing and increased LA excitability was neither necessary nor sufficient for the expression of conditional increases in CS-evoked spike firing. Rather, conditioning-related changes in CS-evoked spike firing were solely determined by the associative history of the CS. Thus, our data support a model in which associative activity in the LA encodes fear memory and contributes to the expression of learned fear behaviors.
Behavioral effects of persistent lymphocytic choriomeningitis virus infection in mice

Lymphocytic choriomeningitis virus (LCMV) is a nonlytic murine virus that provides a valuable model system for studying the behavioral correlates of CNS viral infection. Newborn or immunosuppressed mice infected with LCMV develop a persistent tolerant infection characterized by continuous viral production. Virus can be found in various body organs including lung, liver, kidney, and brain. In brain, neurons are the predominant CNS cells infected and the greatest number of persistently infected neurons are found in the cerebral cortex, hippocampus, other limbic structures and parts of the hypothalamus. Despite continuous infection throughout the animal's life, neurons show no structural injury or dropout. Mice from the DBA/2J strain were infected with LCMV (1000 plaque-forming units) within 18 h of birth and tested for behavioral function as adults. Plaque assays indicated persistent infection in virus-injected mice. Mice were tested for their ability to learn a Y-maze spatial discrimination to avoid the onset of a mild footshock (0.43 mA). The number of correct avoidance responses made during training was taken as a measure of acquisition performance. The virus-infected mice showed a deficit in acquisition of the Y-maze discrimination compared to that seen in vehicle-injected and noninjected controls. Following additional training to reach control levels of performance, the infected mice and the controls were injected with the cholinergic antagonist scopolamine. Scopolamine (2.0 mg/kg) disrupted the performance of the infected mice significantly more than control performance, suggesting that a cholinergic dysfunction accounted for some of the learning deficit. A separate group of virus-infected mice exhibited hypoactivity during the first exposure to a locomotor testing apparatus.(ABSTRACT TRUNCATED AT 250 WORDS)
Distillation column control design using steady state models: Usefulness and limitations

Abstract Steady-state models continue to be powerful and efficient tools for designing control systems for distillation columns. This paper presents a control design procedure and three example applications of this technique to actual columns. One of the columns is now operating and the control performance is presented.
Excitochemical-induced trophic bridging directs axonal growth of transplanted neurons to distal target.

Abstract Brain grafts directly placed in their target regions often lack proper connections and normal regulation. When brain grafts are placed in their ontogenetic normal area, the axonal outgrowth of grafts to distal target regions is a major obstacle. We previously demonstrated that directional axonal growth of grafts can be facilitated by laminin. In this study we demonstrated that excitochemicals induced trophic environment can be strategically used as a bridge to guide transplanted neurons to innervate a distal target of millimeter distance, and has a unique effect on fiber expansion in the target region. To distinguish dopamine (DA) growth from that of transplants, 6-hydroxydopamine was unilaterally injected into medial forebrain bundle to remove dopamine innervation to the striatum. Ibotenic acid (IB), kainic acid (KA), or phosphate buffer (vehicle) were microinjected through a glass-pipet to make a 7 mm long tract between the substantia nigra and the striatum in Sprague-Dawley rats. Gestational 14–15 days brainstem slurry was transplanted either in the same or a separate tract into nigra at the bottom of the bridge. All transplants survived with abundant serotonin (5-HT) and DA neurons. Traceable DA fibers formed distinct bundles from grafts along the length of IB/KA tracts. Upon arrival at their major target regions, fibers from bundles were capable of leaving the tracts, and reinnervating the DA-vacated striatum. The 5-HT fibers formed bundles similar to DA fibers but left the tract earlier upon arrival at their major target the globus pallidus and when arriving at the striatum and cortex. Fibers from grafts with vehicle tracts grew randomly and not into the tract. These results indicate that the trophic effects of chemical lesioning serves as a remarkably effective axonal guidance for more than one type of fetal neuron to innervate distal brain regions. This method has great potential in directing fibers in many transplant models.
Anomalous length dependence of the quantum yield in chromophore-doped liquid crystals

The authors show that, at low dopant concentrations, the quantum yield in chromophore-doped nematic liquid crystals falls off faster than the inverse of the chain length. This effect can be observed in experimental measurements of the quantum yield as a function of the dopant level and chain length. The implications of this result and the possible use of such systems as molecularly based electronic systems are discussed.
VATS pericardiotomy for patients with known malignancy and pericardial effusion: Survival and prognosis of positive cytology and metastatic involvement of the pericardium: A case control study

Abstract Background Pericardiotomy for cancer patients with effusion can alleviate symptoms, but with unclear effect on long term survival. Our experience with VATS technique has produced some long-term survivors. Methods A retrospective review of 62 VATS pericardiotomy for pericardial effusion in patients with known malignancy. Kaplan–Meier survival curves and Log-Rank tests were used for analysis. Results The mean age was 54.8±14.3years (ranging from 19 to 79). The mean hospital stay was 8.7±5.5days. The median survival was 6.75months (range 1month–10years). Overall one-year survival was 44.2%, 3-year survival 17.6%, and 5-year survival 10% after drainage of pericardial effusion. The mean survival in cytology negative patients ( n =21) was 13.4±0.98months, compared to 4.89±0.9months in cytology positive patients ( n =27) ( p =0.0175). The 5-year survival in cytology negative patients was 19.6%, while none of the patients with positive cytology were alive after 36months. The mean survival in patients with no evidence of metastatic disease on the pericardium ( n =28) was 12.8±0.9months, compared to patients with metastatic disease of the pericardium ( n =22) 4.66±0.8months ( p =0.026). Conclusions VATS Pericardiotomy can provide effective long-term drainage in patients with symptomatic pericardial effusion. Positive cytology and metastatic involvement of the pericardium are predictive of worse survival. Survival greater than 5years can be expected in 19% and 17% of patients with negative fluid cytology and negative metastatic disease of the pericardium, respectively.
Updating estimates of union non-union wage differentials in the United States☆

Abstract This study updates earlier research by calculating union wage premiums using both single-equation and simultaneous equations models. It also examines many more subgroups within the population than have earlier studies.
Group A streptococci efficiently invade human respiratory epithelial cells

Although infection by group A streptococci is a model of extracellular mucosal pathogenesis, these organisms can be associated with highly invasive infections resulting in sepsis and shock. Over the last 6 yr this species has renewed its reputation as a significant cause of sepsis and has piqued interest in the mechanism by which some strains are better able to breach mucosal barriers to gain access to the bloodstream than are others. An internalization assay was developed on the basis of resistance of intracellular streptococci to penicillin and gentamicin. Experiments showed that stationary-phase, as opposed to logarithmic-phase, bacteria are efficiently internalized and can persist in cultured human cells. Electron microscopy confirmed that streptococci were contained within intracellular vacuoles. Various strains of streptococci revealed significant differences in their capacity to be internalized. Two type M1 streptococci isolated from blood infections were internalized at frequencies equal to those reported for Salmonella and Listeria monocytogenes and greater than the frequency of a clonal variant from a case of pharyngitis.
Use of particle-loaded membranes to extract steroids for high-performance liquid chromatographic analyses improved analyte stability and detection.

Cortisol, cortisone, corticosterone, prednisone and prednisolone are extracted from serum using the novel particle-loaded octyl (C8)-bonded silica in PTFE membrane. Extracts are directly injected, without further concentration, onto a narrow (2.0 mm) or conventional (4.6 mm) bore octyldecyl (C18) HPLC column. Method performance data demonstrate linearity from 0.4 microgram/dl (low limit of detection) up to at least 60 micrograms/dl. Extraction recoveries exceeded 85% and precision (between-run) R.S.D.s averaged < 5%. Interferences were minimal and selectivity was improved over conventional immunochemical steroid assays. When compared to large particle sorbents packed in columns or to traditional liquid-liquid extractions, the membrane extracted steroids in less time, used less reagent, and had smaller elution volumes, thereby obviating steroid instability/adsorption problems associated with traditional concentrating techniques required to improve analytical sensitivity.
Nondestructive Inspection of Cable Terminations and Splices by X-Ray Analysis

In summary, the author's company has developed a nondestructive method of inspecting potheads and cable splices. While a serious radiation hazard is present, this can be entirely controlled by a few simple precautions, eliminating the requirements for an industrial radiographer. This allows a technician to be trained in a few hours to do the work. Our experience has convinced us of the value of this inspection technique in detecting incipient defects which can be corrected before they cause costly failures. It has been a real pleasure to pass along this new technique developed within Du Pont Company.
Immunotherapy: A novel treatment for non-Hodgkin's lymphoma

Objectives To provide an overview of the principles of immunology, including immunotherapy, and information about monoclonal antibody therapy in the treatment of non-Hodgkin's lymphoma. Data Sources Published literature. Conclusions Immunotherapy is a form of disease treatment that enhances the immune system with the use of biologic agents. One such agent is the monoclonal antibody, which can be combined with a radioisotope (eg, iodine-131 or yttrium-90) or chemotherapeutic drug to deliver treatment directly to tumor cells with less toxicity to normal cells. Implications for Nursing Practice As the field of monoclonal antibody therapy continues to grow, nurses will play an important role in treatment and patient education. Nurses need to become knowledgeable in this area of cancer treatment and gain a better understanding of basic principles involved in immunotherapy.
The making of a feather: Homeoproteins, retinoids and adhesion molecules

We have been using feather development as a model for understanding the molecular basis of pattern formation and to explore the roles of homeoproteins, retinoids and adhesion molecules in this process. Two kinds of homeobox (Hox) protein gradients in the skin have been identified: a 'microgradient' within a single feather bud and a 'macrogradient' across the feather tract. The asynchronous alignment of different Hox macrogradients establishes a unique repertoire of Hox expression patterns in skin appendages within the integument, designated here as the 'Hox codes of skin appendages'. It is hypothesized that these Hox codes contribute to the phenotypic determination of skin appendages. High doses of retinoic acid cause a morphological transformation between feather and scale, while low doses of retinoic acid cause an alteration of the axial orientation of skin appendages. We have tested the ability of molecules directly involved in the feather formation process to mediate the action of the Hox codes, and surmise that adhesion molecules are potential candidates. Using specific Fabs to suppress the activity of adhesion molecules, we have found that L-CAM is involved in the formation of the hexagonal pattern, N-CAM is involved in mediating dermal condensations, tenascin is involved in feather bud growth and elongation, and integrin beta-1 is essential for epithelial-mesenchymal interactions. More work is in progress to fully understand the molecular pathways regulating the feather formation process.