cssi/SciSciGPT-SciSciNet huggingface dataset:
Activation of Protein Kinase PKR Requires Dimerization-induced cis-phosphorylation within the Activation Loop

Protein kinase R (PKR) functions in a plethora of cellular processes, including viral and cellular stress responses, by phosphorylating the translation initiation factor eIF2α. The minimum requirements for PKR function are homodimerization of its kinase and RNA-binding domains, and autophosphorylation at the residue Thr-446 in a flexible loop called the activation loop. We investigated the interdependence between dimerization and Thr-446 autophosphorylation using the yeast Saccharomyces cerevisiae model system. We showed that an engineered PKR that bypassed the need for Thr-446 autophosphorylation (PKRT446∼P-bypass mutant) could function without a key residue (Asp-266 or Tyr-323) that is essential for PKR dimerization, suggesting that dimerization precedes and stimulates activation loop autophosphorylation. We also showed that the PKRT446∼P-bypass mutant was able to phosphorylate eIF2α even without its RNA-binding domains. These two significant findings reveal that PKR dimerization and activation loop autophosphorylation are mutually exclusive yet interdependent processes. Also, we provide evidence that Thr-446 autophosphorylation during PKR activation occurs in a cis mechanism following dimerization.
Diels-Alder ribozyme catalysis: a computational approach.

A computational comparison of the Diels−Alder reaction of a maleimide and an anthracene in water and the active site of the ribozyme Diels-Alderase is reported. During the course of the catalyzed reaction, the maleimide is held in the hydrophobic pocket while the anthracene approaches to the maleimide through the back passage of the active site. The active site is so narrow that the anthracene has to adopt a tilted approach angle toward maleimide. The conformation of the active site changes marginally at different states of the reaction. Active site dynamics contribution to catalysis has been ruled out. The active site stabilizes the product more than the transition state (TS). The reaction coordinates of the ribozyme reaction in TS, RC1-CD1 and RC4-CD2, are 2.35 and 2.33 A, respectively, compared to 2.37 and 2.36 A in water. The approach angle of anthracene toward maleimide is twisted by 18° in the TS structure of ribozyme reaction while no twisted angle is found in TS of the reaction in water. The free ...
Incorporating trip chaining into analysis of destination choice

Abstract A model of destination choice is developed in this study employing “prospective utility” of a destination zone as its attraction measure. The prospective utility accounts for future dependency of destination choice and makes possible relevant treatment of interdependent choices in a trip chain. A parameter is included in the model to represent the magnitude of the future dependency. Empirical estimation results show that destination choice is in fact future dependent and coefficients of travel time and zonal attribute variables may be biased if this depedency is not accounted for.
A model for activity intervention in disaster-stricken communities

Environmental disasters cause deaths, injuries, and destruction of familiar surroundings. Social networks and routines that structure daily life are often left in disarray. To surmount subsequent crises, survivors must master painful feelings, solve problems, and accomplish important tasks, even while they are confused, bereaved, and displaced. Otherwise, coping failure leads to a vicious spiral of loss of self-esteem, distrust of the environment, and abandonment of social roles. Both crisis intervention and disaster literature advocate concrete and practical treatment measures. Activity intervention can prevent and reverse the destructive downward spiral by facilitating victims' most effective coping responses. This paper reviews the pertinent literature and sets forth a theoretical model of occupational therapy in post-disaster settings. Language: en
Regionally specific atrophy of the corpus callosum in AD, MCI and cognitive complaints.

The goal of the present study was to determine if there are global or regionally specific decreases in callosal area in early Alzheimer’s disease (AD) and mild cognitive impairment (MCI). In addition, this study examined the corpus callosum of healthy older adults who have subjective cognitive complaints (CC) but perform within normal limits on neuropsychological tests. We used a semi-automated procedure to examine the total and regional areas of the corpus callosum in 22 patients with early AD, 28 patients with amnestic MCI, 28 healthy older adults with cognitive complaints, and 50 demographically matched healthy controls (HC). The AD, MCI, and CC groups all showed a significant reduction of the posterior region (isthmus and splenium) relative to healthy controls. The AD group also had a significantly smaller overall callosum than the controls. The demonstration of callosal atrophy in older adults with cognitive complaints suggests that callosal changes occur very early in the dementing process, and that these earliest changes may be too subtle for detection by neuropsychological assessments, including memory tests.
Calciotropic Hormones and Bone Markers in the Elderly

There is a lack of substantial data on changes in calciotropic hormones and bone markers in elderly subjects living in North America. Parathyroid hormone (PTH), serum 25-hydroxyvitamin D (25(OH)D) and bone markers (serum osteocalcin and urine N-telopeptide), were measured in 735 Caucasian subjects (235 men and 500 women) aged 65-87 years. There was a significant increase in serum osteocalcin and urine N-telopeptide with age in men, and a significant increase in serum osteocalcin with age in women. Serum PTH and 25(OH)D showed no significant change with age in men or women. After adjusting for age, calcium intake, serum creatinine, season, and weight, mean serum PTH (p = 0.01), serum osteocalcin (p = 0.0001) and 24 h urine N-telopeptide (p = 0.0001) were higher in women than men, and mean serum 25(OH)D (p = 0.0001) and 24 h urine calcium (p = 0.0001) were higher in men than women. Serum PTH was correlated with serum osteocalcin in men and women, r = 0.24, r = 0.17, p < 0.001, but not with urine N-telopeptide. Serum PTH was inversely correlated with serum 25(OH)D (r = -0.25, r = -034,p < 0.001), and positively correlated with serum creatinine (r = 0.14, r = 0.17,p < 0.01) in men and women. The prevalence of serum 25(OH)D levels below 12 ng/ml was only 33% in females and 0.4% in men. Thus vitamin D deficiency was very uncommon in the U.S.A. compared with Europe. Although mean serum PTH was increased in the elderly, only 4-6% had PTH levels above the normal range. In summary, the increase in serum PTH in the elderly can be explained more by changes in vitamin D status than by declining renal function. These data also show significantly higher (p = 0.001) bone remodeling markers in women.
Selenium, chromium and zinc content of proposed SRM 1846 infant formula

A proposed infant formula SRM 1846 has been analyzed for zinc, selenium and chromium by isotope dilution mass spectrometry (IDMS). The precision of the IDMS methods has been sufficient to allow the estimation of the sample homogeneity with respect to these three analytes. Overall means of 60.9±0.9 μg Zn/g (mean±standard deviation) and 76.1±1.9 ng Se/g have been found for 30 determinations. Values for chromium content have been found to depend on the sample preparation method, suggesting possible contamination. Accurary of the zinc, chromium and selenium values has been verified using a certified reference material, SRM 1549 “Non-Fat Milk Powder”.
The effect of acute fluid consumption on measures of impedance and percent body fat estimated using segmental bioelectrical impedance analysis.

The effect of acute fluid consumption on measures of impedance and percent body fat estimated using segmental bioelectrical impedance analysis
Competing, Coverage-Dependent Decomposition Pathways for C2Hy Species on Nickel (111)

Competing, coverage-dependent pathways for ethane (CH_3CH_3) decomposition on Ni(111) are proposed on the basis of quantum mechanics (QM) calculations, performed by using the PBE flavor of density functional theory (DFT), for all C_2H_y species adsorbed to a periodically infinite Ni(111) surface. For CH_2CH_3, CHCH_3, and CCH_3, we find that the surface C is tetrahedral in each case, with the surface C forming bonds to one, two, or three Ni atoms with bond energies scaling nearly linearly (E_(bond) = 32.5, 82.7, and 130.8 kcal/mol, respectively). In each of the remaining six C_2H_y species, both C atoms are able to form bonds to the surface. Three of these (CH_2CH_2, CHCH_2, and CCH_2) adsorb most favorably at a fcc-top site with the methylene C located at an on-top site and the other C at an adjacent fcc site. The bond energies for these species are E_(bond) = 19.7, 63.2, and 93.6 kcal/mol, respectively. The remaining species (CHCH, CCH, and C_2) all prefer binding at fcc-hcp sites, where the C atoms sit in a pair of adjacent fcc and hcp sites, with binding energies of E_(bond) = 57.7, 120.4, and 162.8 kcal/mol, respectively. We find that CHCH_(ad) is the most stable surface species (ΔH_(eth) = −18.6), and an important intermediate along the lowest-energy decomposition pathway for ethane on Ni(111). The second most stable species, CCH_3, is a close competitor (ΔH_(eth) = −18.2 kcal/mol), lying along an alternative decomposition pathway that is preferred for high-surface-coverage conditions. The existence of these competing, low- and high-coverage decomposition pathways is consistent with the experiments. The QM results reported here were used as training data in the development of the ReaxFF reactive force field describing hydrocarbon reactions on nickel surfaces [Mueller, J. E.; van Duin, A: C. T.; Goddard, W. A. J. Phys. Chem. C 2010, 114, 4939−4949]. This has enabled Reactive dynamics studying the chemisorption and decomposition of systems far too complex for quantum mechanics. Thus we reported recently, the chemisorption and decomposition of six different hydrocarbon species on a Ni_(468) nanoparticle catalysts using this ReaxFF description [Mueller, J. E.; van Duin, A: C. T.; Goddard, W. A. J. Phys. Chem. C 2010, 114, 5675−5685].
Tensile and fracture behavior of free-standing copper films

Abstract We have studied tensile deformation and crack growth behavior of free-standing, electron beam evaporated copper films suspended over windows etched in a silicon substrate. In-situ straining experiments were performed on these films using a transmission electron microscope. External tests were conducted on a piezoelectric-driven microtensile system. Macroscopically, these copper films exhibited very low ductility (
A Four-Step Fixed-Grid Method for 1D Stefan Problems

This note is concerned with a fixed-grid finite difference method for the solution of one-dimensional free boundary problems. The method solves for the field variables and the location of the boundary in separate steps. As a result of this decoupling, the nonlinear part of the algorithm involves only a scalar unknown, which is the location of the moving boundary. A number of examples are used to study the applicability of the method. The method is particularly useful for moving boundary problems with various conditions at the front.
A Structural Model on the Determinants and Reactions to Athlete Dissatisfaction

Anecdotal evidence indicates that collegiate athletes who are dissatisfied are more likely to transfer, quit, stage player mutinies, get the head coach fired, and engage in physical violence.Although the causes of satisfaction in sport have been addressed by a few researchers, there has been no empirical attention given to what occurs when an athlete is not satisfied. The purpose of the present study was to test a sport-specific model on personal and situational variables, determinant factors, and consequential reaction alternatives.Since the causes and consequences of job satisfaction-dissatisfaction have been popular topics for research in the field of industrial-organizational psychology, this literature was utilized to develop the basis for this investigation. Questionnaires were administered to 369 male and female Division I college soccer players. Structural equation modeling results demonstrated that the proposed model adequately fit the sample data. As predicted, numerous significant effects were ...
Molecular mechanism of upregulation of survivin transcription by the AT-rich DNA-binding ligand, Hoechst33342: evidence for survivin involvement in drug resistance

We have previously shown that hedamycin, a GC-rich DNA-binding antitumor agent, downregulates survivin transcription (Wu et al. (2005) Molecular mechanism of inhibition of survivin transcription by the GC-rich sequence selective DNA-binding antitumor agent, hedamycin: evidence of survivin downregulation associated with drug sensitivity. J. Biol. Chem., 280, 9745–9751). Here, we report that treatment of cancer cells with Hoechst33342, an AT-rich DNA-binding ligand, upregulated survivin protein, mRNA and promoter activity. Functional analysis of survivin promoter-luciferase constructs followed by in vivo footprinting experiments identified a 28-bp AT-rich DNA element (−908 to −881, designated as H369W) that mediates a major effect of Hoechst33342 on the upregulation of survivin promoter activity. Electrophoresis mobility shift assay (EMSA) experiments showed that Hoechst33342 binds to H369W and abrogates H369W–protein interactions. Intriguingly, there is a highly conserved DNA-binding motif for growth factor independence 1 (Gfi-1), a transcriptional repressor protein, in the H369W DNA element. Accordingly, EMSA experiments demonstrated that either the cold canonical Gfi-1-binding DNA oligonucleotide or the cold H369W specifically competes with H369W–protein complexes. Consistently, anti-Gfi-1 antibody is able to supershift the H369W–protein complex on the EMSA gel. Lastly, our data reveal that upregulation of survivin by Hoechst33342 is involved in cancer drug resistance. We propose that hindrance of H369W–Gfi-1 interactions in the survivin promoter, initiated by Hoechst33342, contributes to upregulation of survivin transcription, and as a consequence, hampers Hoechst33342's cytotoxicity.
Deformation Potentials in Silicon. I. Uniaxial Strain

The rate of splitting with uniaxial strain of the fourfold degenerate ($J=\frac{3}{2}$) valence-band edge of silicon is computed by applying perturbation theory to the Si wave functions calculated previously by Kleinman and Phillips. Based on a "self-consistent" model the calculated values for strain along the [100] and [111] directions are 40% larger than Hensel's experimental values. A primary objective of this calculation was to test the rigid-ion and deformable-ion models often used in the theory of electron-phonon coupling. The rigid-ion model agrees with experiment to within the accuracy of the calculation while the deformable-ion model disagrees with experiment by 300%. For [111] strain the crystal symmetry is so reduced that the separation of the two atoms in each unit cell is not uniquely determined from the macroscopic strain. We have used a model in which the atoms locate themselves in such a way that nearest-neighbor covalent bonds are unchanged in length by shearing strains. This "bond-bending" model is contrasted with a model in which the atomic separation changes with strain like a macroscopic vector. The latter model yields a deformation potential of opposite sign to the experimental one.
Controller for improving the quality of the tandem rolling of hot metal strip

The tandem hot metal strip rolling process presents a difficult control challenge because of its highly complex and nonlinear nature. This challenge is heightened by the hostile hot metal rolling environment which precludes the location of certain sensors to measure variables that are important for control. Based on our previous work using a state-dependent Riccati equation technique for development of a controller for the tandem cold metal rolling process, it is considered that a similar basis could be expanded upon to realize an improved method for the control of this more complex application. In this paper we present a comprehensive model of this process plus the results of our first efforts in the development of a suitable controller, which for control of this application is different than previous methods. The results of simulations of the controller coupled to the model show a strong potential for improvement in the quality of the final product.
Glass‐Ceramic Coatings for Titanium Aluminides

Four glass-ceramic coatings have been successfully developed to function as both hydrogen barriers and oxidation protection on super [alpha]-2 titanium aluminide. The coefficients of thermal expansion (88 [times] 10[sup [minus]7]/C to 117 [times] 10[sup [minus]7]/C) of these coatings provide a good match with that of the alloy, and the coatings show excellent adherence in thermal cycling to 982 C. In addition, the four coatings have measured emittances from 0.67 to 0.80 at this temperature. Finally, the coatings display the desired low hydrogen and oxygen permeation characteristics.
Immunomodulatory therapies in neurologic critical care.

Introduction Neurologic disorders with autoimmune dysregulation are commonly encountered in the critical care setting. Frequently encountered diseases include Guillain–Barre syndrome (GBS), myasthenia gravis, multiple sclerosis, acute demyelinating encephalomyelitis, and encephalitides. Immunomodulatory therapies, including high-dose corticosteroids, plasmapheresis, and intravenous immunoglobulins, are the cornerstone of the treatment of these diseases. Here we review the efficacy and side effects of immunomodulatory therapies commonly utilized in critically ill neurologic patients in the intensive care setting.
Quantification of fluorescein distribution to strangulated rat ileum

Following various periods of strangulation, the fates of intestinal segments were predicted by standard clinical criteria and visual (Wood's lamp) and fluorometric (perfusion fluorometer) assessment of fluorescein distribution. With fluorometry, a means of quantifying fluorescence transmitted via a fiberoptic light guide, the delivery and removal of fluorescein were monitored and analyzed. If either was restricted significantly, tissue death was predicted. Analysis of computerized graphic patterns or simple interpretation of fluorometric readings at two time points predicted tissue fate with 98% accuracy and a 93% negative predictive value. Wood's lamp evaluation had only a 53% accuracy and a 33% negative predictive value, while standard clinical criteria had an 81% accuracy and a 53% negative predictive value. Fluorescein leakage in segments which suffered significant endothelial damage provided staining patterns that incorrectly suggested viability. By monitoring elimination as well as uptake of dye, fluorometry provided much greater discrimination than did Wood's lamp inspection in this setting. In addition, fluorometry was readily repeatable within minutes, as fluorescence remaining from a previous injection could be subtracted from new, postinjection values.
ON A METHOD OF MASS DETERMINATION FOR THE MUON-NEUTRINO

Experiments were performed to refine the upper limit on the mass of the muon-neutrino. The experiments consisted of investigating the shape of the high energy end of the meson ( mu /sup -/) or proton spectra in the LAMBDA yields p + mu /sup -/ + nu /sub mu / process. Other experiments consisted of investigating the shape of the high energy end of the photon spectrum in pi /sup +/ yields gamma + mu /sup +/ + nu /sub mu / and the shape of the high energy end of the meson ( mu /sup +/) spectrum in K/sup +/ yields pi /sup O/ + mu /sup +/ + nu . Experimenta l data are given. (C. E.S.)
Reflections on contemporary business ethics and the ancient wisdom of Kalidasa

In the past two decades, multinational corporations have relied on laws, codes of ethics and in-house awareness programmes for managers to deal with the problems of corporate social responsibility and business ethics. The current global financial crisis and other corporate scandals have exposed the limited utility of these approaches and the glaring need for innovative solutions to the perennial problems of moral philosophy. This paper argues that the secular poetry of the renowned Sanskrit poet Kalidasa can motivate employees and managers to bring about a personal and organisational transformation required for solving the mounting problems of business ethics. Selected verses and aphorisms from two epic poems of Kalidasa – RaghuvaMsha and KumarasaMbhavaM – are examined and interpreted with proper context for their inspirational wisdom and its relevance to ethical behaviour in contemporary global business management.
Response to Drs Spector, Yonker and Bednarek

We thank Drs Spector, Yonker and Bednarek for their comments regarding our study on avoiding endotracheal intubation for neonates during retinopathy of prematurity (ROP) surgery. Their experience indicates, as does ours, that most neonates who have been successfully extubated before ROP surgery do not require endotracheal intubation and mechanical ventilation for the surgery. To avoid intubation, we use nasal prong ventilation during surgery, while Spector et al. attempted to use conscious sedation and no mechanical ventilation. It seems to us that our method results in fewer unscheduled intra- or post-operative intubations. Specifically, they report 9 successful and 6 unsuccessful (intubated during or after surgery) cases, while we report 23 successful and 1 unsuccessful (intubated 2 h after surgery) cases (P=0.008 by Fisher exact test). Perhaps the main point is that neonatologists, anesthesiologists and respiratory therapists who currently re-intubate all neonates for ROP surgery should consider changing that practice to a less-invasive alternative.
4D Reconstruction of the Beating Embryonic Heart From Two Orthogonal Sets of Parallel Optical Coherence Tomography Slice-Sequences

Current methods to build dynamic optical coherence tomography (OCT) volumes of the beating embryonic heart involve synchronization of 2D+time slice-sequences acquired over separate heartbeats. Temporal registration of these sequences is performed either through gating or postprocessing. While synchronization algorithms that exclusively rely on image-intrinsic signals allow forgoing external gating hardware, they are prone to error accumulation, require operator-supervised correction, or lead to nonisotropic resolution. Here, we propose an image-based, retrospective reconstruction technique that uses two sets of parallel 2D+T slice-sequences, acquired perpendicularly to each other, to yield accurate and automatic reconstructions with isotropic resolution. The method utilizes the similarity of the data at the slice intersections to spatio-temporally register the two sets of slice sequences and fuse them into a high-resolution 4D volume. We characterize our method by using 1) simulated heart phantom datasets and 2) OCT datasets acquired from the beating heart of live cultured E9.5 mouse and E10.5 rat embryos. We demonstrate that while our method requires greater acquisition and reconstruction time compared to methods that use slices from a single direction, it produces more accurate and self-validating reconstructions since each set of reconstructed slices acts as a reference for the slices in the perpendicular set.
Selective localization of polyribosomes beneath developing synapses: a quantitative analysis of the relationships between polyribosomes and developing synapses in the hippocampus and dentate gyrus.

Previous studies have revealed that polyribosomes are selectively localized beneath post-synaptic sites on central nervous system (CNS) neurons, and are particularly prominent during periods of synapse growth. The present study evaluates whether polyribosomes are most prominent at a consistent time in the developmental history of the synapse, or instead at a consistent time in the life of the organism regardless of the state of synaptic maturation (suggesting a globally acting factor). We compare the time course of synaptogenesis and the association between polyribosomes and developing synapses in three regions that develop at different rates: the external and internal blades of the dentate gyrus, and the CA1 region of the hippocampus proper. Each region was examined electron microscopically at 1, 4, 7, 10, 15, 20, 28 and over 120 days of age, evaluating: (1) synapse density (the number of synaptic profiles/ area of neuropil), (2) the width of the neuropil layers, (3) the proportion of synapses with underlying polyribosomes, and (4) the number of polyribosome-containing synapses/area of neuropil. As anticipated on the basis of the differences in cytogenesis, the time course of synaptogenesis was different in the three regions. In the external blade of the dentate gyrus, synapse density increased in a nearly linear fashion between birth and 15 days of age, and then continued to increase at a somewhat slower rate until 28 days of age. Synapse development in the internal blade was delayed by several days in comparison to the external blade. In CA1, synapse density increased slowly between 1 and 7 days, and then at a rapid rate between 7 and 28 days of age. In all three regions, the proportion of synapses with underlying polyribosomes was highest between 1 and 7 days of age, and then decreased as synapse density increased. However, the peak in the number of polyribosome-containing synapses/unit area of neuropil occurred at different times in the three regions (4–7 days of age in the external blade of the dentate gyrus and in CA1, and 20 days of age in the internal blade). In addition to further defining the relationship between polyribosomes and developing synapses, the present study provides a data base on the time course of synapse development in the hippocampus and dentate gyrus, which will be useful for comparisons with other measures.
PCR-free quantification of multiple splice variants in a cancer gene by surface-enhanced Raman spectroscopy.

We demonstrate a surface-enhanced Raman spectroscopy (SERS) based array platform to monitor gene expression in cancer cells in a multiplex and quantitative format without amplification steps. A strategy comprising DNA/RNA hybridization, S1 nuclease digestion, and alkaline hydrolysis was adopted to obtain DNA targets specific to two splice junction variants, Δ(9,10) and Δ(5), of the breast cancer susceptibility gene 1 from MCF-7 and MDA-MB-231 breast cancer cell lines. These two targets were identified simultaneously, and their absolute quantities were estimated by a SERS strategy utilizing the inherent plasmon−phonon Raman mode of gold nanoparticle probes as a self-referencing standard to correct for the variability in surface enhancement. The results were then validated by reverse-transcription polymerase chain reaction. Our proposed methodology could be expanded to a higher level of multiplexing for quantitative gene expression analysis of any gene without any amplification steps.
Analysis of a Sector Crack in a Three-Dimensional Voronoi Polycrystal With Microstructural Stresses

The Mode I stress intensity factor of a sector crack in a three-dimensional Voronoi polycrystal is computed by the body force technique. Microstructural stresses arising from the elastic anisotropy of grains (cubic and hexagonal) and the random grain orientations are estimated using the Eshelby procedure and incorporated in the stress intensity factor calculations. For metallic polycrystals, it is shown that the stress intensity factor depends significantly on the elastic anisotropy ratio, the grain orientations, the remote stress state, and the microstructural stresses.
Regulation of cell survival by secreted proneurotrophins.

Neurotrophins are growth factors that promote cell survival, differentiation, and cell death. They are synthesized as proforms that can be cleaved intracellularly to release mature, secreted ligands. Although proneurotrophins have been considered inactive precursors, we show here that the proforms of nerve growth factor (NGF) and the proforms of brain derived neurotrophic factor (BDNF) are secreted and cleaved extracellularly by the serine protease plasmin and by selective matrix metalloproteinases (MMPs). ProNGF is a high-affinity ligand for p75 NTR with high affinity and induced p75 NTR -dependent apoptosis in cultured neurons with minimal activation of TrkA-mediated differentiation or survival. The biological action of neurotrophins is thus regulated by proteolytic cleavage, with proforms preferentially activating p75 NTR to mediate apoptosis and mature forms activating Trk receptors to promote survival.
Elastic short wave instability in extrusion flows of viscoelastic liquids

Abstract An analysis of the stability to short waves of the flow of concentric coextruded polymeric liquids modeled by upper convected Maxwell models is presented. The flow can be unstable to short waves under various conditions on the elastic parameter. The growth rates for the short wave instability in the elastic case are finite at leading order. The same short wave instability is known to be two orders of magnitude smaller in the purely viscous case with growth rates proportional to α −2 for large wavenumber α. It is argued that this instability could appear in systems with low surface tension, as in polymer-depleted solutions at the walls of a pipe. Some speculative scenarios concerning the appearance of sharkskin after the loss of adhesion, leading to wet slip, are advanced.
Ablation of atrial fibrillation: are the lines drawn?

i a n w l n a p r n c n h m s Atrial fibrillation is associated with increased morbidity nd mortality, while sinus rhythm has been associated with mproved survival in patients with heart disease. The imited efficacy of antiarrhythmic drugs, and the possibility hat left atrial ablation may alleviate arrhythmia symptoms ithout incurring the increased morbidity and mortality een with drug use, has fueled interest in developing effecive ablation strategies. However, ablation may introduce ts own complications, and optimizing the procedure reuires offering the minimal lesion set necessary to prevent rrhythmia recurrence. Defining the optimal lesion set has een hampered by our imperfect understanding of arrhythogenesis and by the heterogeneity of atrial fibrillation echanisms. Atrial fibrillation can strike in self-terminating paroxsms in an otherwise normal heart, or it may be present hronically, associated with advancing age, hypertension, iastolic dysfunction, and cardiac structural abnormaliies. The arrhythmia may arise from rapidly discharging oci emanating predominantly from sites of smooth muscle– ardiac muscle interface (most notably the pulmonary eins), or from substrate abnormalities that promote and ccommodate reentrant waves. Whether there is a coninuum of disease progression from trigger-driven to subtrate-mediated arrhythmia, or whether these variants reflect wo distinct populations of patients, is not known. Furtherore, the mechanism of an individual patient’s arrhythmia s often not clear clinically. Given the heterogeneity of echanisms it is not surprising that the optimal ablation esion set remains undefined. The success of the surgical Maze procedure in disrupting he substrate for multiple wavelets (and, incidentally, in
Safe-Time: Distributed Real-Time Monitoring of cKNN in Mobile Peer-to-Peer Networks

A continuous k nearest neighbor (cKNN) query is a query that continuously returns a set of k nearest moving objects (mobile hosts) to a given query point. For example, report three nearest moving sensors to a given location continuously. Most existing research efforts focus on centralized solutions. In a mobile peer-to-peer network (M-P2P), a centralized approach incurs expensive communication cost. In this paper, we propose Safe-Time - a distributed solution for cKNN given a stationary query point for M-P2P. The two key features are as follows. 1) Actual execution of a cKNN query is not needed during a safe-time period since the query result is guaranteed to remain the same during this period. 2) Once the safe-time expires, execution of a cKNN query involves only objects in a circular band of width equal to the estimated distance between the kth and the k + 1th nearest neighbors. To further reduce communication cost for dense queries, we introduce Unite-Safe-Time that executes one virtual query derived from nearby queries instead of executing each of them separately. Our simulation result shows that the proposed distributed solutions outperform a centralized solution under a range of conditions. Safe-Time incurs up to 2/3 less communication cost compared to a centralized solution. Unite-Safe-Time shows up to 1/3 less communication cost than Safe-Time in our study.
Discrete Fiber Reinforced Polyurea for Hazard Mitigation

This research investigated the development and characterization of different discrete fiber-reinforced polyurea systems for infrastructure applications. The behavior of various systems consisting of several polyureas with different fiber configurations was evaluated. Polyurea coating systems were previously evaluated for blast mitigation and impact resistance, and showed to be adequate in containing debris scatter from blast and impact (Carey and Myers, 2009a, 2009b). The purpose of further testing was an effort to develop a polyurea system for multi-hazard and/or repair-retrofit applications. The addition of fiber to a polymer coating provides improved stiffness and strength to the composite system while the polyurea base material provides ductility. Coupon tensile testing was conducted to determine the material mechanical properties in this study. The two parameters that were varied throughout testing were fiber volume fraction and fiber length. E-Glass fiber was used during specimen fabrication. Several optimal composite configurations of polyurea and fiber resulted from this coupon testing.
Hypothalamic Luteinizing Hormone (LH): Characteristics and Response to Hypophysectomy

This study describes the finding of an immunoassayable and bioassayable luteinizing hormone (LH) in the rat hypothalamus. Validation of the immunoassay forLH inhypothalamicextractsis presented. Chromatographic patterns of hypothalamic LH were found to be identical with those of rat pituitary LH. Radioimmunoassay values of serial dilutions of hypothalamic extract paralleled dilution values of rat pituitary LH. Furthermore, such homogenates promoted release of testosterone from dispersed rat testis cells in vitro. This effect was largely abolished by prior incubation of homogenate with an antiserum to rat LH. Following removal of the anterior pituitary, LH levels in the hypothalamus persist but drop significantly, signifying that this particular brain-based LH is partially dependent on the presence of a functioning pars distalis. Immunoassayable LH measured in other areas of the rodent central nervous system did not change following hypophysectomy.
Configural and contextual prioritization in object-based attention

When attention is directed to a location within an object, other locations within that object also enjoy an attentional advantage. Recently we demonstrated that this object-based advantage is mediated by increased attentional priority assigned to locations within an already attended object and not to early sensory enhancement due to the “spread” of attention within the attended object (Shomstein & Yantis, 2002). At least two factors might contribute to the assignment of attentional priority, one related to the configuration of objects in a scene and the other related to the probability of target appearance in each location imposed by task contingencies. We investigated the relative contribution of these factors by cuing one end of one of a pair of rectangles; a subsequent target appeared most often in the cued location. We manipulated attentional priority setting by varying (1) the probability that a target would appear in each of two uncued locations and (2) the cue to target stimulus onset asynchrony (SOA). On invalidly cued trials, the target appeared in thehigh-probability location (defined by an absolute spatial location, e.g., upper right) 83% of the time and in thelow-probability location (e.g., lower left) 17% of the time. In both conditions, uncued targets appeared in the cued object half the time and in the uncued object half the time. At short SOAs, the same-object and probability effects were approximately additive. However, at longer SOAs, the same-object effects disappeared, and reaction times depended exclusively on location probability. These results suggest that observers adopt an implicitconfigural scanning strategy (in which unattended locations within an attended object have high priority) or an implicitcontextual scanning strategy (in which objectively high-probability locations have high priority) depending on task contingencies and the amount of time that is available to deploy attention.
Recent Developments in Aqueous two-Pease Extraction in Bioprocessing

(1998). Recent Developments in Aqueous two-Pease Extraction in Bioprocessing. Separation and Purification Methods: Vol. 27, No. 1, pp. 1-49.
The Language of Liberty and Law: James Wilson on America's Written Constitution

Although contemporary Americans take it for granted that a “constitution” is a written document, written constitutions were almost unprecedented at America's founding. James Wilson, one of the most significant yet overlooked of America's founders, offers a comprehensive theory of America's written constitution. Wilson argues that the written-ness of the U.S. Constitution serves two essential functions. As an initial matter, it memorializes the primacy of liberty by announcing that the authority of government derives only from a free people. Perhaps more importantly, however, the written constitution uplifts and refines the character of its citizens, and thus helps to constitute a people. A review of Wilson's writings and speeches reveals how, even in a rights-centric political order, the written constitution helps to cultivate moderate and civic-minded citizens without diminishing the fundamental importance of individual rights.
What affects influenza vaccination rates among older patients? An analysis from inner-city, suburban, rural, and veterans affairs practices

Abstract Background Despite strong evidence of the effectiveness of influenza vaccination, immunization rates have reached a plateau that is below the 2010 national goals. Our objective was to identify facilitators of, and barriers to, vaccination in diverse groups of older patients. Methods A survey was conducted in 2000 by computer-assisted telephone interviewing of patients from inner-city health centers, Veterans Affairs (VA) outpatient clinics, rural practices, and suburban practices. The inclusion criteria were age ≥66 years and an office visit after September 30, 1998. Results Overall, 1007 (73%) interviews were completed among 1383 patients. Influenza vaccination rates were 91% at VA clinics, 79% at rural practices, 79% at suburban practices, and 67% at inner-city health centers. There was substantial variability in vaccination rates among practices, except at the VA. Nearly all persons who were vaccinated reported that their physicians recommended influenza vaccinations, compared with 63% of unvaccinated patients ( P P P Conclusion Older patients need intentional messages from physicians that recommend vaccination. Furthermore, more patient education is needed to counter myths about adverse reactions.
Optical Constants of Silver, Gold, Copper, and Aluminum. II. The Index of Refraction n

The reflectivities of Ag, Au, Cu, and Al were measured at an angle of incidence of 45°, in the wavelength range of 0.40μ to 0.95μ at glass-metal and air-metal interfaces. These reflectivities, together with previously determined values of the absorption coefficient k, were used to calculate the index of refraction n. Samples were prepared by evaporation and deposition from the vapor. The important experimental results are: (1) The ratios of the reflectivities in the s plane to those in the p plane agreed with the theoretical values. This result indicates that the boundary conditions required for the application of the equations of electromagnetic theory have been satisfied. (2) Ageing and annealing resulted in increased reflectivity at both air-metal and glass-metal interfaces. (3) The values of n obtained from aged or annealed samples were in many cases considerably lower than previously published values.
Ultrasound-guided fine-needle aspiration biopsy remains a valid approach in the evaluation of nonpalpable breast lesions.

The use of ultrasound-guided fine-needle aspiration (FNA) biopsy for nonpalpable breast lesions varies considerably. This retrospective study stresses the role of breast FNA in evaluating sonographically suspicious nonpalpable breast masses using a probabilistic reporting system. One hundred and eight consecutive ultrasound-guided FNA biopsies diagnosed as positive (32), suspicious (8), atypical (11), benign (55), and unsatisfactory (2) were analyzed and correlated with 61 subsequent surgical specimens. All positive cytologies showed carcinoma on histology; suspicious cases were followed by 5 carcinomas, 2 fibroadenomas, and 1 papillary lesion. Follow-up of atypical cases included 4 carcinomas, 3 fibroadenomas, and 2 papillary lesions, while all 10 biopsies following benign cytology showed fibrocystic changes. Two cases with suspicious sonographic findings but unsatisfactory cytology had lobular carcinoma. The remainder of the benign and atypical cases were followed clinically and radiographically for at least 10 months and had no evidence of carcinoma. Positive predictive values were positive, 100%; suspicious, 63%; atypical, 36%; benign, 0%. Most (40/43; 93%) carcinomas were invasive. In conclusion, ultrasound-guided FNA for nonpalpable breast lesions is highly accurate, and probabilistic reporting helps direct patient management. Diagn. Cytopathol. 2004;30:325–331. © 2004 Wiley-Liss, Inc.
Strategy Inventory for Language Learning–ELL Student Form: Testing for Factorial Validity

As the school-aged English language learner (ELL) population continues to grow in the United States and other English-speaking countries, psychometrically sound instruments to measure their language learning strategies (LLS) become ever more critical. This study adapted and validated an adult-oriented measure of LLS (50-item Strategy Inventory for Language Learning [SILL]; Oxford, 1990) for school-aged ELLs in a sample of 1,057 elementary, middle, and high school students. The two-stage validation process resulted in a shorter, 28-item version of the instrument, which we entitled the SILL-ELL Student Form. The results of confirmatory factor analyses indicated a good fit to the validation (GFI = .92, CFI = .93, RMSEA = .04, SRMR = .05) and combined (GFI = .95, CFI = .95, RMSEA = .03, SRMR = .04) samples. The new measure has strong psychometric characteristics for use with school-aged ELLs to diagnose their use of LLS in six distinct categories and is approximately half as long as the original SILL, which enhances it.s pragmatic value for busy classrooms. Additionally, this study addressed some of the theoretical issues with strategy categorization noted in the literature. Other applications of the measure for practice and research are discussed. [ABSTRACT FROM AUTHOR]
Meridional variability in dissolved organic matter stocks and diagenetic state within the euphotic and mesopelagic zone of the North Atlantic subtropical gyre

article i nfo Article history: Dissolved combined neutral sugars (DCNS) Total hydrolyzable carbohydrates (TCHO) Dissolved organic matter (DOM) Diagenetic state North Atlantic Ocean Concentrations of dissolved organic carbon (DOC), bulk carbohydrates (TCHO), and dissolved combined neutral sugars (DCNS) were measured during a meridional U.S. CO2 — Climate Variability (CLIVAR) Repeat Hydrography Project cruise (A20) from 7-43°N in the North Atlantic. Maxima in DOC, TCHO, and DCNS concentrations and carbohydrate yields (TCHO and DCNS as a % of DOC) were observed within the most stratified surface waters south of 27°N. Concentrations and yields of TCHO and DCNS decreased to the north and south of their respective maxima, indicating significant variability in the apparent diagenetic state of dissolved organic matter (DOM) along the transect. Changes in apparent diagenetic state to the north appeared to be largely related to the previous entrainment of recalcitrant DOM during deep winter/spring convective mixing. Deep mixing was less of a factor in the more stratified waters to the south where the decrease in carbohydrate yields indicated diagenetic alteration of the surface-accumulated pool of DOM. Overall, diagenesis decreased both carbohydrate yields and the mol% of galactose and mannose+xylose content and in deep waters resulted in a significant enrichment in the mol% of glucose. TCHO yields and the mol% of glucose revealed significant differences in DOM quality between subtropical mode water (STMW) and upper Antarctic Intermediate Water (uAAIW) that were related to the extent of water mass ventilation.
A new R&M measure and its estimation

The reliability and maintainability measure is referred to as MTUT. It is the mean time to restore an equipment and its maintenance system to its original working status; it is expressed as a proportion of the mean time to failure for any given equipment. This measure integrates maintenance and repair time expenditures of all types from three levels of maintenance. Other measures discussed in the literature such as availability, mean time to repair, and average queue length are compared to MTUT. A testing program for the demonstration phase of equipment development is presented. Estimation and discrimination procedures are derived for MTUT using data from the outlined testing program. Large-sample theory is used to construct both interval estimates and discrimination procedures for the MTUT, using data acquired from the assessment phase of equipment development. >
Gradual phyletic evolution at the generic level in early Eocene omomyid primates

Analysis of dental morphology in over 600 stratigraphically controlled specimens of tarsier-like primates from early Eocene strata in the Bighorn Basin, Wyoming, provides important new data for understanding the tempo and mode of evolution in primates. Here we describe two evolutionary transitions at the generic level in separate lineages of the family Omomyidae. In both lines transformation occurred not only continuously (rather than by abrupt appearance of new morphologies followed by stasis), but also in mosaic fashion, with greater variation in certain characters preceding a shift to another character state. In one lineage this resulted in a significant change in dental adaptation. These data support a gradual model of dental evolution and are inconsistent with the punctuated equilibria model. Together with other reported cases, the data suggest that gradualism is much more prevalent than proponents of punctuated equilibria have argued.