cssi/SciSciGPT-SciSciNet huggingface dataset:
HIV-1 Nef Binds PACS-2 to Assemble a Multikinase Cascade That Triggers Major Histocompatibility Complex Class I (MHC-I) Down-regulation ANALYSIS USING SHORT INTERFERING RNA AND KNOCK-OUT MICE

Human immunodeficiency virus, type 1, negative factor (Nef) initiates down-regulation of cell-surface major histocompatibility complex-I (MHC-I) by assembling an Src family kinase (SFK)-ZAP70/Syk-phosphoinositide 3-kinase (PI3K) cascade through the sequential actions of two sites, Nef EEEE65 and PXXP75. The internalized MHC-I molecules are then sequestered in endosomal compartments by a process requiring Nef Met20. How Nef assembles the multikinase cascade to trigger the MHC-I down-regulation pathway is unknown. Here we report that EEEE65-dependent binding to the sorting protein PACS-2 targets Nef to the paranuclear region, enabling PXXP75 to bind and activate a trans-Golgi network (TGN)-localized SFK. This SFK then phosphorylates ZAP-70 to recruit class I PI3K by interaction with the p85 C-terminal Src homology 2 domain. Using splenocytes and embryonic fibroblasts from PACS-2-/- mice, we confirm genetically that Nef requires PACS-2 to localize to the paranuclear region and assemble the multikinase cascade. Moreover, genetic loss of PACS-2 or inhibition of class I PI3K prevents Nef-mediated MHC-I down-regulation, demonstrating that short interfering RNA knockdown of PACS-2 phenocopies the gene knock-out. This PACS-2-dependent targeting pathway is not restricted to Nef, because PACS-2 is also required for trafficking of an endocytosed cation-independent mannose 6-phosphate receptor reporter from early endosomes to the TGN. Together, these results demonstrate PACS-2 is required for Nef action and sorting of itinerant membrane cargo in the TGN/endosomal system.
Carbon dioxide and the δ18O record of late-Quaternary climatic change: a global model

A dynamical model for the late-Quaternary global variations of δ18O, mean ocean surface tempeature τ, ice mass I, deep ocean temperature θ, and atmospheric carbon dioxide concentration μ, is constructed. This model consists of two diagnostic equations (for δ18O and τ), and three prognostic equations (for I, θ, and μ) of a form studied extensively in previous articles. The carbon dioxide equation includes forcing by a representation of the Milankovitch earth-orbital radiation effects, and contains a basic instability that drives a free oscillation of period near 100,000 years. The system is constrained to conserve mass and energy, contain physically plausible feedbacks including a system time constant no greater than 10.000 years, and be robust (i. e., structurally stable in the presence of expected noise levels and uncertainties in values of coefficients). Within the limits of these constraints, coefficients are chosen such that (i) the solution gives a good fit to the observed SPECMAP δ18O variations, and (ii) the ice mass variations are qualitatively similar to the δ18O variations. The predicted long term variations of sea surface temperature and atmospheric carbon dioxide are in reasonably good agreement with the limited observational evidence available for these quantities, while the predicted variations of deep ocean temperature remain to be verified when paleoclimatic estimates of this quantity become available. The relative contributions of ice mass changes and surface water temperature changes to the variations of δ18O at any time are given by the model.
Identification of Robot Kinematic Parameters Using Evolutionary Algorithms

ABSTRACTThis article proposes an alternative heuristic solution based on Genetic Algorithms (GAs) to the manipulator kinematic parameters identification problem. GAs, which refer to a family of algorithms that rely on analogies to natural evolution, have been applied to a wide range of optimization problems with extremely encouraging results. GAs outperform classical optimization techniques since they do not suffer from the disadvantages that are inherent to these methods. The formulation and the application of Genetic Algorithms for the solution of the above problem are discussed and the concept is verified by simulations in which the kinematic parameters of serial and parallel manipulators are identified. The results obtained demonstrate the simplicity and efficiency of this approach.
FIR filtering of images on a lattice with periodically deleted samples

The notion of periodically deleting samples from a discrete image without information loss is reviewed. The set of signals that satisfy the deletion theorem is generalized to a class that is closed under convolution and hence any filtered version of a member of the class is also a member. A polyphase type structure is developed that allows FIR filtering of the image with deleted samples. An example is then given which shows that there are savings in computer memory and computation when this method is used. >
Normal hearing in α-galactosidase A-deficient mice, the mouse model for Fabry disease

Fabry disease (OMIM 301500) is a rare X-linked recessive disorder caused by mutations in the alpha-galactosidase gene (Gla). Loss of Gla activity leads to the abnormal accumulation of glycosphingolipids in lysosomes of predominantly vascular endothelial cells. Clinically the disorder presents with angiokeratomas, clouding of the cornea, and renal, cardiac, and cerebrovascular complications. In addition, there is an increased incidence of sensorineural hearing loss in Fabry patients. In this study, we investigated the loss of alpha-galactosidase A activity on hearing function in Gla-deficient mice (Gla(tm1Kul)). Gla mRNA was readily detected in the cochlea of 2- and 12-month old C57BL/6J and C3HeB/FeJ mice. The targeted allele was introgressed to the normal hearing C3HeB/FeJ strain to eliminate confounding genetic background effects. Auditory brain stem responses (ABR) to click, 8-, 16-, and 32 kHz stimuli measured at regular intervals from animals at the N4 backcross generation and from N4F1 hybrids demonstrated normal hearing in hemizygous and homozygous mutant mice up to 76 weeks of age. By histological criteria, the cyto-architecture of the mutant cochlea showed a normal appearance. The data demonstrate that in the mouse the loss of alpha-galactosidase A activity is genetically or biochemically buffered and not sufficient per se to cause an appreciable degree of hearing impairment.
A cognitive approach to dogmatism: An investigation into the relationship of verbal working memory and dogmatism

Abstract This study investigated the relationship of working memory to open and closed belief systems. Two hundred college students completed a working memory span test to measure verbal working memory, and Rokeach’s Dogmatism Scale (1956) . Regression analysis was undertaken to determine the contribution of verbal working memory to dogmatism. A negative correlation was found between dogmatism scores and working memory scores ( p = .002) confirming the hypothesis that those participants who display a larger working memory capacity would show lower levels of dogmatic beliefs than participants displaying a smaller working memory capacity. Error analysis was employed to determine the significance of inhibition processes; indicating that capacity limits in verbal working memory, and not processing deficits, were primarily responsible for poor working memory scores. Dogmatism was not found to be related to gender, age, ethnicity, religious affiliation, academic major, or level of education.
Delayed efficacy of Beauveria bassiana foliar spray applications against Colorado potato beetle: Impacts of number and timing of applications on larval and next-generation adult populations

Abstract Spray programs comprising multiple or single foliar applications of the fungal pathogen Beauveria bassiana strain GHA (Bb-GHA) made during morning (AM) vs. evening (PM) hours were tested against Colorado potato beetle Leptinotarsa decemlineata (CPB) in small research plots of potatoes over multiple field seasons, and efficacy against larval and first-generation adult populations was evaluated. The pathogen (formulated as BotaniGard WP®) was applied at the rate of 2.5 × 1013 conidia in a spray volume of 468–480 L per ha. Modes of efficacy were investigated by collecting pre-pupal larvae and holding them in soil cages in the field and laboratory. Results revealed that larval control achievable with multiple-spray programs was poor regardless of environmental moisture conditions, but that emerging adult populations were reduced by an average of 80% (range 58–93%) relative to control populations. Programs comprising a single application of Bb targeted against late-instar larvae reduced adult populations by an average of 60% (range 36–75%). Overall mean differences in efficacy of PM vs. AM applications were not significant in terms of larval control and defoliation damage. Emergence of next-generation adults was significantly lower in the PM vs. AM treatments, but differences were small in terms of percent control. Average yields from the Bb-GHA multiple-spray programs were 18% greater than those from the controls; the mean 5% increase resulting from the Bb-GHA single-spray programs was not significant. Observations indicated that moderate to high rates of inoculation and infection were achieved under a broad range of environmental conditions in the crop canopy, but larvae persisted until they entered the soil to pupate. Most deaths due to mycosis occurred among pre-pupal larvae in their pupation cells in the soil. These results, in combination with similar findings of delayed efficacy reported by other researchers, indicate that foliar applications of Bb could be a significant component of an IPM program aimed at suppressing CPB populations on large farms or over large areas.
Influence of polymer characteristics and melt‐spinning conditions on the production of fine denier poly(ethylene terephtalate) fibers. Part II. Melt spinning dynamics

The effect of poly(ethylene terephtalate) (PET) polymers with different rheological properties as well as the effect of different spinning conditions on the minimum attainable takeup denier were determined. The spinning conditions were modified by the use of heating devices, insulation plate, and convergence guides tested in the range of take-up speeds from 2000 to 6000 m/min. It is postulated that the important parameter in the production of fine denier PET fiber is the spinline tension level, which must be kept low in order to obtain finer denier fibers. The increase of take-up velocity and the threadline length increase the spinline stress level, and therefore the minimum denier attainable increases. The effect of the apparent elongational viscosity of the polymer and the threadline cooling profile can be thought as affecting the draw-down tension and therefore the minimum take-up denier. Higher apparent elongational viscosity level or faster cooling generates higher spinline tension resulting in higher minimum denier. The effects of the apparent elongational viscosity is more significant at a speed of 5000 m/min. This is in part due to the already very small denier obtained at speeds up to 4000 m/min, where the conditions of uniformity of polymer flow seem to be more important.
A Revisitation of Species Circumscriptions and Evolutionary Relationships in Scouleria (Scouleriaceae)

Abstract The genus Scouleria has three to five traditionally recognized species from Northeast Asia, western North America, and southern South America. While the genus is well defined by several morphological synapomorphies, species circumscriptions have varied, especially with respect to narrow versus broad concepts of S. aquatica. We used Maximum Likelihood and Bayesian phylogenetic analyses of ITS and the chloroplast loci ndhA, trnS-trnG, and rpL32-trnL to test species circumscriptions and to re-evaluate an earlier hypothesis of evolutionary relationships within the genus. Our results strongly support the recognition of S. marginata and S. patagonica as currently recognized based on geography and morphology. Phylogenetic patterns within S. aquatica sensu lato support the resurrection of two northeast Asian species, S. rschewinii and S. pulcherrima as distinct from North American S. aquatica sensu stricto. In addition, the recognition of the North American S. “species A” sensu Norris and Shevock (2004) ...
Berezin transform and Weyl-type unitary operators on the Bergman space

For D the open complex unit disc with normalized area measure, we consider the Bergman space La(D) of square-integrable holomorphic functions on D. Induced by the group Aut(D) of biholomorphic automorphisms of D, there is a standard family of Weyl-type unitary operators on La(D). For all bounded operators X on La(D), the Berezin transform X is a smooth, bounded function on D. The range of the mapping Ber: X → X is invariant under Aut(D). The “mixing properties” of the elements of Aut(D) are visible in the Berezin transforms of the induced unitary operators. Computations involving these operators show that there is no real number M > 0 with M‖ X‖∞ ≥ ‖X‖ for all bounded operators X and are used to check other possible properties of X. Extensions to other domains are discussed.
Time at risk: Toward a banking titanic?

The Year 2000 problem is quickly becoming known as potentially the biggest challenge in the brief history of information technology. The complexity of the problem is particularly true for financial institutions, such as banks, which rely heavily on information technology and are interconnected and interdependent. This article reviews the millennium problem and its possible implications for banks and financial institutions worldwide. © 1999 John Wiley & Sons, Inc.
Autosomal recombination in males ofDrosophila melanogaster caused by a transmissible factor

The phenomenon of male recombination has been found in more than twenty per cent of lines derived from wild-caughtDrosophila melanogaster. The recombination appears to be caused by a factor which is attached to, and transmitted with chromosomes, but which is readily transposed to other chromosomes. The possibility exists, however, that the factor is also capable of independent existence in the nucleoplasm. Extensive testing indicates that the factor is not contagious. The factor has been named “Male Recombinant Factor” or “MRF”.
Heteroepitaxial growth of tungsten oxide films on sapphire for chemical gas sensors

Abstract The performance of chemiresistive gas sensors made from semiconducting metal oxide films is influenced by film stoichiometry, crystallographic structure, surface morphology and defect structure. To obtain well-defined microstructures, heteroepitaxial WO3 films were grown on r-cut and c-cut single crystal sapphire substrates using rf magnetron Ar/O2 reactive sputtering of a W target. On r-cut sapphire, an epitaxial tetragonal WO3 phase is produced at a 450°C deposition temperature whereas 650°C growth stabilizes an epitaxial monoclinic WO3 phase. On c-cut sapphire, a metastable hexagonal WO3 phase is formed. RHEED and X-ray diffraction indicate that the films have a ‘polycrystalline epitaxial structure’ in which several grains are present, each having the same crystallographic orientation. STM analysis of the film surfaces reveals morphological features that appear to be derived from the substrate symmetries. The monoclinic phase has a step/terrace growth structure, has the smallest mosaic spread in XRD rocking curves and exhibits the highest degree of reproducibility suggesting that it is the best suited for sensor applications. Measurements of film conductivity versus temperature indicate that the charge transport mechanisms are also dependent on the crystallographic phase and microstructure of the WO3 films.
Interior/exterior classification of polygonal models

We present an algorithm for automatically classifying the interior and exterior parts of a polygonal model. The need for visualizing the interiors of objects frequently arises in medical visualization and CAD modeling. The goal of such visualizations is to display the model in a way that the human observer can easily understand the relationship between the different parts of the surface. While there exist excellent methods for visualizing surfaces that are inside one another (nested surfaces), the determination of which parts of the surface are interior is currently done manually. Our automatic method for interior classification takes a sampling approach using a collection of direction vectors. Polygons are said to be interior to the model if they are not visible in any of these viewing directions from a point outside the model. Once we have identified polygons as being inside or outside the model, these can be textured or have different opacities applied to them so that the whole model can be rendered in a more comprehensible manner. An additional consideration for some models is that they may have holes or tunnels running through them that are connected to the exterior surface. Although an external observer can see into these holes, it is often desirable to mark the walls of such tunnels as being part of the interior of a model. In order to allow this modified classification of the interior, we use morphological operators to close all the holes of the model. An input model is used together with its closed version to provide a better classification of the portions of the original model.
Faidherbia albida on the Tonga Plateau of southern Zambia: an agroecological analysis

Faidherbia albida is a tree species indigenous to semi-arid regions of Africa that reportedly substantially increases maize (Zea mays) yields in its immediate vicinity. In southern Zambia, F. albida is widely used in indigenous maize farming systems and this has apparently increased over the past two decades. Using a combination of interviews, group meetings, and observations, this study sought to understand why this species seems to have recently been embraced, while other technological innovations apparently have not. We observed a bimodal age distribution of the trees in agricultural fields and posit that the missing cohorts were removed as weeds as a result of evolving notions of what constituted modern farming practices in the emerging maize economy. With subsequent research and social promotion of the beneficial effects of F. albida, farmers now allow the trees to grow in their fields. A holonic analysis points to the important relationship of F. albida to contexts that shaped past and current uses ...
The attitude‐behavior discrepancy problem: Revisited

(1971). The attitude‐behavior discrepancy problem: Revisited. Quarterly Journal of Speech: Vol. 57, No. 4, pp. 418-428.
The role of polarization of Xe by di- and monovalent cations in 129Xe NMR studies in zeolite A

We consider the role of polarization in the adsorption of Xe in zeolites of type A by direct comparative analysis of the adsorption isotherms, distributions of occupancies, and 129Xe NMR chemical shifts of Xe(n) in cages containing CaxNa12-2x ions per alpha cage (x = 0, 1, 2, 3, 5). We find that the qualitative trends in the adsorption isotherms, and in the progressions of Xe(n) chemical shifts (for n = 0-8 in cages with x = 0, 1 Ca2+ ions and for n = 0-5 in cages with x = 2, 3 Ca2+ ions) upon increasing the level of Ca2+ ion for Na+ ion substitution could only be accounted for by including polarization of the Xe atom by the zeolite framework and its ions. This system, which permits observation of individual Xe(n) peaks and of directly comparable adsorption isotherms in several cage types, provides a good model system for the interpretation of the more general case in which only the overall average 129Xe NMR chemical shift is observed in open network zeolites, arising from free exchange of Xe among cavities of variable occupancy and variable cation distribution.
PIXE spectrometry in Archaeometry: The development of a system with high spatial resolution

Abstract A new PIXE facility has been constructed at the Bartol Foundation with a tightly-focused proton beam (typically 50 μm across) that allows a variety of inhomogeneous archaeological artifacts to be studied in spatial detail. This paper discusses the practical need for micro-PIXE research in archaeology — applications could include the analysis of metal residues in smelting slag, the solder joins of Classical jewelry, sound metal in corroded bronzes and individual color bands on core-formed glass vessels — and summarizes the role of the various components that comprise the facility itself.
Experiments on orbital dynamics in superfluid 3 He-A

The response of the orbital degrees of freedom of superfluid $^{3}\mathrm{He}$-$A$ to a magnetic field suddenly rotated through a small angle is a decaying exponential rather than an oscillatory response. Analysis of the field and temperature dependence of the time constant supports the Cross-Anderson orbital-viscosity theory as complemented by the Pethick-Smith relaxation-time theory but reveals a discrepancy in the susceptibility-anisotropy energy near ${T}_{c}$.
Childhood abuse as a possible locus for early intervention into problems of violence and psychopathology

Reviewed research on abuse in childhood. Physical abuse, sexual abuse, psychological abuse, as well as children witnessing parents abuse each other, were all found to be associated with later problems with violence and psychopathology. No causal conclusions could be drawn because of the correlational nature of the research. Also, research into possible interventions was reviewed. At least somewhat effective interventions for stopping abuse once it begins are available for all of the types of abuse. However, there are no data on the effects of these interventions on long-term problems of violence or psychopathology. It is recommended that psychopathologists and therapists collaborate in long-term studies which utilize intervention as a tool for experimentally investigating the relationships between childhood abuse and later problems of violence or psychopathology.
A Moving Magnet Actuator for Large Range Nanopositioning

In this paper, we present the design, fabrication, and testing of a moving magnet actuator (MMA) for large range (∼10mm) nanopositioning. MMAs are direct-drive, single-phase electromagnetic linear actuators that provide frictionless and backlash-free motion. These qualities, along with an adequate motion range, make MMAs promising candidates for large range nanopositioning. In this work, we identify actuator- and system-level performance criteria and associated design tradeoffs, and use this knowledge to systematically and concurrently design an MMA and a double parallelogram flexure bearing. The resulting actuator provides a force output per unit square root power of 4.56N/W, better than 9% force uniformity with respect to stroke, and a low moving mass of 106g. An integrated thermal management system is also incorporated as part of the actuator in order to mitigate the heat dissipated from the MMA coils. The overall single-axis motion system was fabricated and tested to demonstrate a 36Hz open-loop bandwidth and less than 4nm (RMS) steady-state positioning noise over a 10mm motion range. Preliminary closed-loop design and testing highlight the potential of the proposed actuator in nanopositioning.Copyright © 2011 by ASME
Tests of quantum mechanics based on interference of photons

Abstract Some difficulties with a modified version of the Pfleegor-Mandel experiment recently proposed by Garuccio, Popper and Vigier are pointed out, and a different modification is proposed in order to test the conventional quantum mechanical interpretation.
IEEE 802.11 FHSS receiver design for cluster‐based multihop video communications

Recently, we proposed an ad hoc, cluster-based, multihop network architecture for video communications using IEEE 802.11 FHSS (Frequency Hopping Spread Spectrum) wireless LAN (WLAN) technology with 2GFSK (2-level Gaussian Frequency Shift Keying) modulation capable of 1 Mb s−1 transmission. To increase the transmission rate to 2 Mb s−1 for higher-quality video communications, we evaluated the performance of the IEEE 802.11 FHSS system when a 4GFSK modulation option is selected. Since the 2 Mb s−1 system utilizing 4GFSK modulation is not very efficient in terms of Radio Frequency (RF) range, to improve its performance for multihop applications a combination of diversity and noncoherent Viterbi equalizer are considered. For video transmission, we employed a bitstream-splitting technique together with a packet-based error-protection strategy to combat packet drops under multipath fading conditions. The real-time transport protocol (RTP), user datagram protocol (UDP), and Internet protocol (IP) are used for video streaming. This includes an RTP packetization scheme to control the packet size and to improve the error-resilient decoding of the partitioned video signal. The paper includes the simulation results showing the effects of the receiver design and diversity on the quality of the received video signals. Copyright © 2002 John Wiley & Sons, Ltd.
Interaction of Brain-Type Creatine Kinase with its Transition State Analog: Kinetics of Inhibition and Conformational Changes

AbstractThe effects of components of the transition state analog (creatine, MgADP, planar anion) on the kinetics and conformation of creatine kinase isozyme BB from monkey brain was studied. From analysis of the reaction time course using the pH stat assay, it was shown that during accumulation of the reaction products (ADP and creatine phosphate), among several anions added, nitrate proved the most effective in inhibiting catalytic activity. Maximum inhibition (77%) was achieved with 50 mM nitrate. The Km for ATP was 0.48 mM and in the presence of 2.5 mM nitrate, 2.2 mM; for ATP in the presence of the dead-end complex, creatine and ADP, the apparent Km was 2.0 mM and theK wasO.16mM; in the presence of the transition state analog, MgADP + NO3” + creatine, the K was estimated to be 0.04 mM.Ultraviolet difference spectra of creatine kinase revealed significant differences only in the presence of the complete mixture of the components of the transition state analog. Comparison of gel nitration elution profil...
CEO Tenure and Entrepreneurial Orientation Within Family and Nonfamily Firms

The current research investigates how entrepreneurial orientation changes during a chief executive officer (CEO)'s tenure in family and nonfamily firms. Based on secondary data collected from 210 firms representing five industries, the results show an inverse U-shaped relationship between CEO tenure and entrepreneurial orientation, consistent with the executive life cycle literature. Moreover, in family firms the shape of the inverse U is less pronounced and the level of entrepreneurial orientation peaks considerably later in the CEO's tenure when compared with nonfamily firms.
The case against climate regulation via oceanic phytoplankton sulphur emissions

The CLAW hypothesis advanced the idea of biological regulation of Earth's climate. In the proposed feedback loop, cloud condensation nuclei and cloud albedo are regulated up or down by oceanic phytoplankton through the medium of dimethyl sulphide emissions, such that climate remains moderate. CLAW, named after the authors of the Nature article that introduced it in 1987 (Charlson, Lovelock, Andreae and Warren, see go.nature.com/alfv2n ), proved influential and spawned two decades of intensive research investigating the required mechanisms. Patricia Quinn and Timothy Bates have now synthesized this sprawling field and argue that there is no strong evidence to support any of the critical steps required by CLAW. Instead, contributions by organic and non-organic compounds suggest a far more complex reality. More than twenty years ago, a biological regulation of climate was proposed whereby emissions of dimethyl sulphide from oceanic phytoplankton resulted in the formation of aerosol particles that acted as cloud condensation nuclei in the marine boundary layer. In this hypothesis—referred to as CLAW—the increase in cloud condensation nuclei led to an increase in cloud albedo with the resulting changes in temperature and radiation initiating a climate feedback altering dimethyl sulphide emissions from phytoplankton. Over the past two decades, observations in the marine boundary layer, laboratory studies and modelling efforts have been conducted seeking evidence for the CLAW hypothesis. The results indicate that a dimethyl sulphide biological control over cloud condensation nuclei probably does not exist and that sources of these nuclei to the marine boundary layer and the response of clouds to changes in aerosol are much more complex than was recognized twenty years ago. These results indicate that it is time to retire the CLAW hypothesis.
Co(III) complexes with coordinated carboxamido nitrogens and thiolato sulfurs as models for Co-containing nitrile hydratase and their conversion to the corresponding sulfinato species.

Recent spectroscopic data suggest that the Co(III) site in Co-containing nitrile hydratase is ligated to carboxamido nitrogens and thiolato sulfurs and most possibly one or more of the bound thiolates exist as sulfenato and/or sulfinato groups. The absence of any Co(III) complex with such coordination makes it quite difficult to predict the reactivity of this kind of Co(III) site. In this paper, the Co(III) complexes of two designed ligands PyPepSH2 (1) and PyPepRSH2 (2) have been reported. The two complexes, namely, (Et4N)[Co(PyPepS)2] (3) and Na[Co(PyPepRS)2] (4) are the first examples of Co(III) complexes with carboxamido nitrogens and thiolato sulfurs as donors. The average Co(III)−Namido and Co(III)−S distances in these complexes lie in the range 1.90−1.92 and 2.22−2.24 A, respectively. Reaction of H2O2 with both complexes readily affords Na[Co(PyPepSO2)2] (5) and Na[Co(PyPepRSO2)2] (6), species in which the thiolato sulfurs are converted to sulfinato (SO2) groups. Such conversion also occurs when so...
Platelet aggregation in relationship to plasma catecholamines in patients with hypertension

Plasma catecholamine concentration and platelet aggregation were studied in 22 patients with uncomplicated primary hypertension and 13 age-matched normotensive, healthy subjects at rest and in some during isometric handgrip exercise. The effect of norepinephrine (NE) infusion upon platelet aggregation was also examined. Plasma catecholamine concentration was slightly higher in the hypertensive than the normotensive group, but the difference was not significant. However, platelet aggregation to ADP was significantly greater in the hypertensive than the normotensive subjects. Exercise increased significantly both catecholamines and aggregation in both groups. Platelet aggregation was correlated with age (r = 0.62, P < 0.01) and plasma NE (r = −0.34, P < 0.05 for the total group of subjects). The infusion of NE increased significantly plasma NE and platelet aggregation and there was an inverse correlation between NE increase and threshold decrease (r = −0.69, P < 0.05). Thus, plasma catecholamines are important determinants of platelet aggregation. However, in our study, uncomplicated primary hypertension was not associated with abnormal plasma catecholamine concentration. It is likely that the observed abnormal platelet aggregability to ADP represents a secondary phenomenon, possibly related to more advanced atherosclerotic vascular changes in hypertensive than normotensive subjects.
Equation of state for neutron matter at finite T in a relativistic mean-field theory☆

Abstract The equation of state for neutron matter at all temperatures is presented in a relativistic mean-field theory which describes known nuclear matter. Isotherms are calculated and discussed and some limiting analytic forms of the equation of state are given.
A comparison of propofol and chloral hydrate for sedation of young children during magnetic resonance imaging scans

Summary The purpose of this study was to compare the effects of two methods of providing sedation for young children undergoing magnetic resonance imaging (MRI) studies on efficiency of scanner utilization. Thirty-nine patients were randomized to receive either propofol or chloral hydrate. Age and gender distributions were not significantly different between the groups. Induction time was significantly less for propofol than for chloral hydrate (6 ± 3 min vs 41 ± 9 min; P < 0.0001); and recovery time for propofol was significantly shorter than for chloral hydrate (18 ± 7 min vs 47 ± 28 min; P < 0.0001). Procedure times were not significantly different. Three of 19 patients who received chloral hydrate moved and their scans were interrupted; two of these received propofol. None of the patients in the propofol group moved. Utilization efficiency of the MRI scanner, defined as 100 ± (Procedure Time)/(Induction Time + Procedure Time), was 87 ± 6% for propofol and 45 ± 13% for chloral hydrate. These data demonstrate that propofol sedation allows the MRI scanner to be utilized more efficiently than chloral hydrate sedation.
Modeling and testing smooth structural changes with endogenous regressors

Abstract Modeling and detecting parameter stability of econometric models is a long standing problem. Most existing estimation and testing methods are designed for models without endogeneity. Little attention has been paid to models with endogeneous regressors, which may arise in many scenarios in economics. In this paper, we first consider a time-varying coefficient time series model with potential time-varying endogeneity. A local linear two stage least squared estimation is developed to estimate coefficient functions. The consistency and asymptotic normality of the estimator are derived. Furthermore, a nonparametric test is proposed to check smooth structural changes as well as abrupt structural breaks with possibly unknown change points in regression models with potential endogeneity. The idea is to compare the fitted values of the unrestricted nonparametric time-varying coefficient model and the restricted constant parameter model. The test has an asymptotic N ( 0 , 1 ) distribution and does not require any prior information about the alternatives. A simulation study highlights the merits of the proposed estimator and test. In an application, we estimate the New Keynesian Phillips Curve for the US nonparametrically and find strong evidence against its stability.
How Do We Teach Family Therapy Theory

A rich variety of ideas and strategies are found in the literature that addresses how family therapy theories should be taught. Differences in teaching strategies and practices are influenced by differences in the theories of family therapy. However, even within specific theoretical schools, there is more agreement among educators about what skills should be taught than there is on how to teach such skills. This column addresses the multiplicity of ideas on how to teach family therapy theories.
Restrictive Expression of Acid-Sensing Ion Channel 5 (Asic5) in Unipolar Brush Cells of the Vestibulocerebellum

Acid-sensing ion channels (Asic) are ligand-gated ion channels in the Degenerin/Epithelial Na+ channel (Deg/ENaC) family. Asic proteins are richly expressed in mammalian neurons. Mammals express five Asic genes: Asic1-5. The gene product of Asic5 is an orphan member of the family about which little is known. To investigate Asic5 expression, we created an Asic5 reporter mouse. We find that Asic5 is chiefly expressed in the brain in the cerebellum, specifically in the ventral uvula and nodulus of the vestibulocerebellum. Here, Asic5 is restrictively expressed in a subset of interneurons in the granular layer. The locale, distinctive shape and immunohistochemical properties of these Asic5-expressing interneurons identify them as unipolar brush cells (UBC). Asic5 is richly expressed in a subset of UBCs that also express the metabotropic glutamate receptor 1α (mGluR1α) but not those that express calretinin. Results from single cell RT-PCR and electrophysiological examination of these cells are consistent with this identity. Such observations are consistent with Asic5 playing a key role in the physiology of UBCs and in the function of the vestibulocerebellum.
Amelioration of the typical cognitive phenotype in a patient with the 5pter deletion associated with Cri-du-chat syndrome in addition to a partial duplication of CTNND2.

Cri-du-chat is a rare congenital syndrome characterized by intellectual disability, severe speech/developmental delay, dysmorphic features, and additional syndromic findings. The etiology of this disorder is well known, and is attributed to a large deletion on chromosome 5 that typically ranges from band 5p15.2 to the short arm terminus. This region contains CTNND2, a gene encoding a neuronal-specific protein, delta-catenin, which plays a critical role in cellular motility and brain function. The exact involvement of CTNND2 in the cognitive functionality of individuals with Cri-du-chat has not been fully deciphered, but it is thought to be significant. This report describes an 8-year-old African-American female with a complex chromosome 5 abnormality and a relatively mild case of cri-du-chat syndrome. Because of the surprisingly mild cognitive phenotype, although a karyotype had confirmed the 5p deletion at birth, an oligo-SNP microarray was obtained to further characterize her deletion. The array revealed a complex rearrangement, including a breakpoint in the middle of CTNND2, which resulted in a partial deletion and partial duplication of that gene. The array also verified the expected 5p terminal deletion. Although the patient has a significant deletion in CTNND2, half of the gene (including the promoter region) is not only preserved, but is duplicated. The patient's milder cognitive and behavioral presentation, in conjunction with her atypical 5p alteration, provides additional evidence for the role of CTNND2 in the cognitive phenotype of individuals with Cri-du-chat.
Laboratory Comparisons of Sulfuryl Fluoride Toxicity and Mean Time of Mortality Among Ten Termite Species (Isoptera: Hodotermitidae, Kalotermitidae, Rhinotermitidae)

Ten termite species representing three families [ Zootermopsis angusticollis (Hagen), Hodotermitidae; Cryptotermes cavifrons Banks, Incisitermes minor (Hagen), Incisitermes snyderi (Light), Neotermes jouteli (Banks), Kalotermes approximatus Snyder, Kalotermitidae; Coptotermes formosanus Shiraki, Reticulitermes tibialis Banks, Reticulitermes flavipes (Kollar), and Prorhinotermes simplex (Hagen), Rhinotermitidae] were fumigated with sulfuryl fluoride for 22 h in the laboratory. R. flavipes and R. tibialis were most sensitive (LAD30 = 13.42 and 14.52 mg-h/liter, respectively), and I. minor was least sensitive (LAD50 = 30.36 mg-h/liter). Greatest and least postfumigation grand mean time of mortality (±SEM) was 3.11 ± 0.04 and 1.58 ± 0.05 d for R. tibialis and I. snyderi , respectively. Z. angusticollis had a uniquely steep probit-mortality slope.
In vitro processing of the adenosine analog formycin A to the mono-, di-, and triphosphate by a soluble multienzyme system from mouse liver

The adenosine kinase activity present in a soluble preparation from rat liver was investigated using formycin A (FoA), a fluorescent analog of adenosine as the phosphoryl acceptor and ATP as the donor. Reversed-phase high-performance liquid chromatography (h.p.l.c.) was used to separate substrate from product, and the progress of the phosphorylation reaction was followed by monitoring fluorometrically the amount of formycin 5'-monophosphate (FoMP), and the AMP analog, that was formed. The results showed that while FoMP was formed during the reaction indicating that an adenosine kinase activity was present, both formycin 5'-di- and triphosphate (FoDP and FoTP respectively), the corresponding analogs of ADP and ATP, were also formed, suggesting than an adenylate kinase activity was present. This result was confirmed with FoMP as the substrate and showing the formation of FoDP and FoTP. Other experiments carried out with FoMP as the substrate revealed the formation of FoA. Taken together, these results indicated that a 5'-nucleotidase activity as well as an adenylate kinase was present. Using this analog and h.p.l.c., it has been possible to demonstrate for the first time in an in vitro system the complete salvage of a nucleoside to the triphosphate level.
Mycetoma Within an Intralobar Sequestration: Evidence Supporting Acquired Origin for This Pulmonary Anomaly

A rare example of an intralobar sequestration (ILS) containing a fungal mycetoma is reported. This finding indicates the presence of a communication between the ILS and the airways, thus supporting the theory that ILSs are acquired lesions, rather than congenital malformations.
Neuroselective current perception threshold quantitative sensory test: A re-evaluation

To the Editor: Subsequent to the publication of our paper,"Peripheral neuropathy secondary to docetaxel (Taxotere),"1 we re-evaluated the Current perception threshold (CPT) quantitative sensory testing data we had gathered using guidelines recommended in previous articles.2,3 …
Danazol Inhibits Steroidogenesis in the Rat Testis in Vitro

The effects of danazol on steroidogenesis in vitro in the rat testis were examined by studying: 1) androgen synthesis in rat Leydig cells cultured with danazol, 2) danazol binding to rat testis microsomal cytochrome P-450, and 3) enzyme kinetics of danazol inhibition of the microsomal enzymes of testicular steroidogenesis. Concentrations of danazol as low as 1 micrometer suppressed LH-stimulated testosterone and androstenedione production in cultured Leydig cells. The addition of danazol to a preparation of testicular microsomes elicited a type I cytochrome P-450 binding spectrum, with an apparent spectral dissociation constant (Ks) of 4.8 micrometer. Danazol inhibited progesterone and 17alpha-hydroxy-progesterone binding to microsomal P-450 with apparent spectral inhibition constants of 2.4 micrometer and 2.8 micrometer, respectively. Danazol competitively inhibited 3beta-hydroxy-delta5-steroid dehydrogenase-isomerase (apparent enzymatic inhibition constant, KI = 5.8 micrometer), 17alpha-hydroxylase (KI = 2.4 micrometer), 17,20 lyase (KI = 1.9 micrometer), and 17beta-hydroxysteroid dehydrogenase (KI = 4.4 micrometer). These findings indicate that low concentrations of danazol directly inhibit steroidogenesis in the rat testis in vitro.
Cardiac calcium currents at the level of single channels.

Properties of cardiac Ca channels have come into sharper focus with the advent of single cell preparations and suction pipette recording methods. We briefly summarize our present picture of the gating and permeation properties of the conventional, dihydrophyridine-sensitive type of Ca channel (L-type). Distincitive features of a second type of voltage-gated Ca channel (T-type) are discussed.
Aging in a dish: age-dependent changes of neuronal survival, protein oxidation, and creatine kinase BB expression in long-term hippocampal cell culture

Results from different experimental systems demonstrate that increased oxidative damage plays a role in normal aging and age-associated pathology. In the current study, long-term cultures of hippocampal neurons were examined as a model system. It was established that neuronal survival in long-term culture decreases according to the Gompertz law and that neuronal "aging in the dish" is associated with increased oxidative damage of cell proteins. The increase of protein carbonyl formation in aged neurons was demonstrated both by Western blot analysis for oxidized proteins and by in situ immunocytochemical method, which was developed to analyze protein oxidation in fixed cells. In aging neuronal cultures, a gradual increase in creatine kinase (CK) content but decreased activity of enzyme per immunoreactive protein was found, suggesting the accumulation of inactive CK molecules. The increase in CK content was not a result of generalized protein elevation, since analysis of beta-actin content showed a time-dependent loss, probably reflecting decreased number of cellular processes with aging. These findings, showing "aging in a dish," consistent with the notion that aging is associated with increased protein oxidation, provide a system for study of age-related neurodegenerative disorders associated with oxidative stress.
Spin-Orbit Coupling and Ion Displacements in Multiferroic TbMnO3

The magnetic and ferroelectric (FE) properties of TbMnO3 are investigated on the basis of relativistic density functional theory calculations. We show that, due to spin-orbit coupling, the spin-spiral plane of TbMnO3 can be either the bc or ab plane, but not the ac plane. As for the mechanism of FE polarization, our work reveals that the ‘‘pure electronic’’ model by Katsura, Nagaosa, and Balatsky is inadequate in predicting the absolute direction of FE polarization. Our work indicates that to determine the magnitude and the absolute direction of FE polarization in spin-spiral states, it is crucial to consider the displacements of the ions from their centrosymmetric positions. Recent studies on magnetic ferroelectric (FE) materials have shown that electric polarization can be significantly modified by the application of a magnetic field [1–7]. Perovskite TbMnO3 with a spin-spiral magnetic order is a prototypical multiferroic compound with a gigantic magnetoelectric effect [2]. Currently, there are two important issues concerning the FE polarization of TbMnO3. One concerns the origin of FE polarization. Model Hamiltonians studies of spin-spiral multiferroic compounds have provided two different pictures. In the Katsura-Nagaosa-Balatsky (KNB) model [5], the hybridization of electronic states induced by spin-orbit coupling (SOC) leads to a FE polarization of the charge density distribution even if the ions are not displaced from their centrosymmetric positions. In contrast, the model study by Sergienko and Dagotto [7] concluded that oxygen ion displacements from their centrosymmetric positions are essential for the FE polarization in multiferroic compounds [8]. When carried out with the ions kept at their centrosymmetric positions, density functional theory (DFT) calculations [9] for the spin-spiral states of LiCuVO4 predict FE polarizations that agree reasonably well in magnitude with experiment [10], which is in apparent support of the KNB model [5]. It is, therefore, important to check which model, the KNB or the ‘‘ion-displacement’’ model, is relevant for the FE polarization in TbMnO3. The other issue concerns the spin-spiral plane of TbMnO3. Under a magnetic field, the spin-spiral plane of TbMnO3 can be either the bc plane or the ab plane, but not the ac plane. To explain this observation, it is necessary to probe the magnetic anisotropy of the Mn 3 ion. The magnetic anisotropy of the Tb 3 ion might be also relevant for the magneto
Phased-array intracardiac echocardiographic imaging of acute cardiovascular emergencies: Experimental studies in dogs.

Abstract Background: We evaluated a newly developed phased-array intracardiac echocardiographic catheter. Objective: Our aim was to evaluate the imaging capability of this new ICE catheter in an animal model simulating acute cardiovascular abnormalities. Methods: ICE images were obtained from the right atrium during (1) acute left ventricular dysfunction; (2) acute coronary occlusion; (3) pericardial effusion and tamponade; and (4) pulmonary embolism. Results: Left ventricular dysfunction, induced experimentally by halothane inhalation, resulted in a fall in echocardiography-calculated ejection fraction from 47% ± 11% to 25% ± 10%, P Conclusion: This new phased-array ICE catheter may be a useful clinical tool for the diagnosis of heart failure, ischemia, tamponade, and pulmonary embolism. (J Am Soc Echocardiogr 2002;15:1309-14.)