cssi/SciSciGPT-SciSciNet huggingface dataset:
The Invariant Measure for the Satellite Ground Station View Period Problem

Planners for the Deep Space Network at JPL require long-term forecasts of ground station view periods. The standard approach requires orbit integration up to 20 years. The geometry of the satellite groundtrack and station mask suggests the use of ergodic theory. An invariant measure was found which enabled the application of the Ergodic Theorem to this problem. The total view period for a circular orbit is given by a definite integral over the sphere. This paper presents the derivation of the invariant measure.
The Local Forces Acting on the Mechanotransduction Channel in Hair Cell Stereocilia

In hair cells, mechanotransduction channels are located in the membrane of stereocilia tips, where the base of the tip link is attached. The tip-link force determines the system of other forces in the immediate channel environment, which change the channel open probability. This system of forces includes components that are out of plane and in plane relative to the membrane; the magnitude and direction of these components depend on the channel environment and arrangement. Using a computational model, we obtained the major forces involved as functions of the force applied via the tip link at the center of the membrane. We simulated factors related to channels and the membrane, including finite-sized channels located centrally or acentrally, stiffness of the hypothesized channel-cytoskeleton tether, and bending modulus of the membrane. Membrane forces are perpendicular to the directions of the principal curvatures of the deformed membrane. Our approach allows for a fine vectorial picture of the local forces gating the channel; membrane forces change with the membrane curvature and are themselves sufficient to affect the open probability of the channel.
Identification and characterization of the promoter region of Kaposi's sarcoma-associated herpesvirus ORF11.

Abstract Open reading frame 11 (ORF11) of Kaposi's sarcoma-associated herpesvirus belongs to a herpesviral homologous protein family that is conserved among members of the gamma-herpesvirus subfamily. Little is known about the function of ORF11 and how this viral gene is regulated in KSHV life cycle. In this study, we have characterized the major transcript of the ORF11 gene, which is located adjacent and in the opposite orientation to a well-characterized viral IL-6 gene. Northern blot analysis revealed that the ORF11 gene is lytic viral gene with delayed-early expression kinetics. We have determined the 5′ and 3′ untranslated region of the unspliced ORF11 transcript and identified both the transcription start site and the transcription termination site. Core promoter region, representing ORF11 promoter activity, was mapped to a 160 nt fragment 5′ most proximal to the transcription start site. A functional TATA box was identified in the core promoter region. We also found that the characterized ORF11 gene promoter region is not responsive to Rta, the KSHV lytic switch protein. Our data help to elucidate transcription regulation of the KSHV ORF11 gene and to understand the biology of ORF11 in KSHV life cycle.
Free 11-hydroxycorticosteroid levels in working dogs as affected by exercise training.

The influence of 6 weeks of progressive exercise training on free 11-hydroxycorticosteroid (11-OHCS) levels before, during and after standardized bouts of treadmill running was investigated in male mongrel dogs. Chronic tracheostomies and omocervical arterial catheterizations allowed for simultaneous assessment of energy expenditure, 11-OHCS, eosinophil and glucose levels at rest, during running, at exhaustion (rectal temperature of 108 F) and after 30 min of recovery. The mean (N = 7) resting level of plasma 11-OHCS was 1.9±0.4 μg/100 ml. Graded increases in work intensity were accompanied by linear increases in both energy expenditure (V02) and plasma free 11-OHCS levels. While responses were variable for lighter work loads, 11-OHCS levels increased significantly during “heavy” work to 5.3 ±1.5 μg/100 ml. At “exhaustion” a further increase to 8.0 ± 1.7 μg/ 100 ml was observed. No significant correlation was found, however, between the 11-OHCS levels and either the eosinophil counts or the rate of energy...
Why Did Henry Stimson Spare Kyoto from the Bomb?: Confusion in Postwar Historiography

While the United States Air Force systematically bombed the majority of urban Japan during the final months of World War II, the city of Kyoto remained nearly untouched, offering an almost pristine nuclear target. Yet Secretary of War Henry Stimson, the central figure behind the sparing of the city, struck Kyoto from the list of nuclear targets. Stimson’s efforts to preserve Kyoto have received only passing attention from postwar scholars. A review of relevant postwar historiography, however, reveals three frameworks that provide explanations for the sparing of the city: moralist, orthodox, and revisionist. The moralist approach views Stimson’s decision to preserve Kyoto as an effort to live up to the principles of an earlier era. Orthodox scholars suggest Stimson’s decision was driven by a desire to save lives and end the war quickly. Revisionists, by contrast, argue that Stimson’s calculus was shaped by concern over the growing specter of a standoff with the Soviet Union. The imprecise and at times contradictory explanations furnished thus far fail to provide a convincing interpretation of Kyoto’s role in the final years of the war. To understand Stimson’s adamancy requires examining references to the city in his diary and placing them into broader context to gain a sense of how the city related to the strategic objectives and challenges facing the secretary of war.
A persistent infection of Vero cells by egg-adapted mumps virus

Abstract Serial subculture of Vero cells infected with the chick embryo adapted Enders strain of mumps virus gives rise to a low level productive though persistent infection. Persistently infected cultures exhibit minimal cytopathology; however, widely dispersed foci of multinucleate cells are almost always present. Neither infected cell nor virus growth is temperature sensitive. Biological and biochemical evidence indicate that defective interfering particles are replicated along with infectious (nondefective) virus during the course of the persistent infection, although the plaque-purified inoculum virus stock contained only genome size RNA. With continued cell passage a heterogeneous, changing population of subgenomic sized viral RNA accumulates, suggesting that defective interfering (DI) RNA species are evolving from virion RNA, with no single DI RNA predominating. Since such factors as interferon, antibody, and temperature-sensitive mutants are absent from this system, DI particles are the likely factor modulating this persistent infection.
Polyreactivity and Autoreactivity among HIV-1 Antibodies

It is generally acknowledged that human broadly neutralizing antibodies (bNAbs) capable of neutralizing multiple HIV-1 clades are often polyreactive or autoreactive. Whereas polyreactivity or autoreactivity has been proposed to be crucial for neutralization breadth, no systematic, quantitative study of self-reactivity among nonneutralizing HIV-1 Abs (nNAbs) has been performed to determine whether poly- or autoreactivity in bNAbs is a consequence of chronic antigen (Ag) exposure and/or inflammation or a fundamental property of neutralization. Here, we use protein microarrays to assess binding to >9,400 human proteins and find that as a class, bNAbs are significantly more poly- and autoreactive than nNAbs. The poly- and autoreactive property is therefore not due to the infection milieu but rather is associated with neutralization. Our observations are consistent with a role of heteroligation for HIV-1 neutralization and/or structural mimicry of host Ags by conserved HIV-1 neutralization sites. Although bNAbs are more mutated than nNAbs as a group, V(D)J mutation per se does not correlate with poly- and autoreactivity. Infrequent poly- or autoreactivity among nNAbs implies that their dominance in humoral responses is due to the absence of negative control by immune regulation. Interestingly, four of nine bNAbs specific for the HIV-1 CD4 binding site (CD4bs) (VRC01, VRC02, CH106, and CH103) bind human ubiquitin ligase E3A (UBE3A), and UBE3A protein competitively inhibits gp120 binding to the VRC01 bNAb. Among these four bNAbs, avidity for UBE3A was correlated with neutralization breadth. Identification of UBE3A as a self-antigen recognized by CD4bs bNAbs offers a mechanism for the rarity of this bNAb class. IMPORTANCE Eliciting bNAbs is key for HIV-1 vaccines; most Abs elicited by HIV-1 infection or immunization, however, are strain specific or nonneutralizing, and unsuited for protection. Here, we compare the specificities of bNAbs and nNAbs to demonstrate that bNAbs are significantly more poly- and autoreactive than nNAbs. The strong association of poly- and autoreactivity with bNAbs, but not nNAbs from infected patients, indicates that the infection milieu, chronic inflammation and Ag exposure, CD4 T-cell depletion, etc., alone does not cause poly- and autoreactivity. Instead, these properties are fundamentally linked to neutralization breadth, either by the requirement for heteroligation or the consequence of host mimicry by HIV-1. Indeed, we show that human UBE3A shares an epitope(s) with HIV-1 envelope recognized by four CD4bs bNAbs. The poly- and autoreactivity of bNAbs surely contribute to the rarity of membrane-proximal external region (MPER) and CD4bs bNAbs and identify a roadblock that must be overcome to induce protective vaccines.
Experiments with multi-protocol RMI in Java

Remote Method Invocation is an adaptation of the remote procedure call paradigm for object-oriented environments. RMI allows clients to seamlessly invoke methods of objects within remote servers. Communication between the client and server is based upon an agreed protocol stack that defines connection management rules, message formats, and data encoding.There are numerous communication libraries for Java that enable remote method invocations over different wire protocols. Standard Java RMI is based on the Java Remote Method Protocol, JRMP. RMI-IIOP [6] is alternative implementation that enables connectivity with legacy CORBA systems. JAX-RPC [5] provides means to invoke methods via SOAP, making it possible to interact with Web Services. Also, many alternative RMI implementations have been developed in order to overcome standard Java RMI and JRMP performance issues [3, 1, 2]. The common drawback of these libraries is that they are designed to be used exclusively (e.g. they usually bind clients to a particular wire protocol via stubs generated at compile time) and they do not interoperate well.RMIX is a meta-RMI framework that, rather than itself providing communication capabilities, defines a common facade through which variety of wire protocols may be used in a uniform way. Concrete protocols are supported by independent, dynamically pluggable modules, i.e. protocol service providers. Such an approach permits removal of the dependence of distributed applications on particular communication protocols: at the server side, remote objects may be uniformly exported over various protocols; at the client side, the need for statically generated stub classes is eliminated.Some projected usage scenarios of RMIX include: (1) loosely coupled distributed systems with peer-to-peer protocol negotiation (dynamic discovery is especially beneficial in this case as it makes it possible to add or upgrade protocol providers at run-time); (2) applications that are multi-protocol by nature (e.g. distributed scientific applications that communicate using an efficient native protocol but offer SOAP endpoints for monitoring and control purposes); (3) standard Java RMI applications ported to RMIX in order to eliminate the burden associated with generation and distribution of stub classes.Currently, RMIX offers two concrete protocol providers: RMIX-JRMPX, a lightweight layer over standard Java RMI, and RMIX-XSOAP, based on XSOAP [4] and using SOAP 1.1 as its wire protocol.In addition to multiple protocol support, RMIX offer other enhancements such as customizable remote object endpoints, and asynchronous invocation mode. More information about RMIX can be found at http://www.mathcs.emory.edu/rmix/.
Analysis and Operational Characteristics of a Reduced Parts Converter for Bipolar Excitation of SR Drives

Switched reluctance machines (SRM's) are leading candidates for automotive applications. It has been proven that utilizing a bipolar excitation strategy will result in increasing torque production and decreasing torque ripple. However, utilizing an asymmetric bridge bipolar converter induces a cost increase in terms of the necessary power electronic devices, thus employing a reduced part converter for bipolar excitation is advantageous. This work reports on the analysis and operational characteristics of a reduced parts converter topology for bipolar excitation of a 4-phase 8/6 SRM placing emphasis on basic control strategies, and converter losses with comparison to an asymmetric bridge bipolar converter.
Oral methoxsalen photochemotherapy of mycosis fungoides

The cutaneous manifestations of mycosis fungoides have been successfully treated in nine patients for 16 to 28 months with oral methoxsalen and subsequent irradiation with longwave ultraviolet light. The efficacy of this therapy was confirmed in one patient, who showed complete clearing of generalized plaques after 1 month (12 treatments) except for a shielded control area which worsened during this period. Methoxsalen photochemotherapy may prove a valuable addition to therapies currently available for mycosis fungoides and may obviate some of the problems associated with conventional management of this disorder.
Human Variation in Short Regions Predisposed to Deep Evolutionary Conservation

The landscape of the human genome consists of millions of short islands of conservation that are 100% conserved across multiple vertebrate genomes (termed “bricks”), the majority of which are located in noncoding regions. Several hundred thousand bricks are deeply conserved reaching the genomes of amphibians and fish. Deep phylogenetic conservation of noncoding DNA has been reported to be strongly associated with the presence of gene regulatory elements, introducing bricks as a proxy to the functional noncoding landscape of the human genome. Here, we report a significant overrepresentation of bricks in the promoters of transcription factors and developmental genes, where the high level of phylogenetic conservation correlates with an increase in brick overrepresentation. We also found that the presence of a brick dictates a predisposition to evolutionary constraint, with only 0.7% of the amniota brick central nucleotides being diverged within the primate lineage—an 11-fold reduction in the divergence rate compared with random expectation. Human single-nucleotide polymorphism (SNP) data explains only 3% of primate-specific variation in amniota bricks, thus arguing for a widespread fixation of brick mutations within the primate lineage and prior to human radiation. This variation, in turn, might have been utilized as a driving force for primate- and hominoid-specific adaptation. We also discovered a pronounced deviation from the evolutionary predisposition in the human lineage, with over 20-fold increase in the substitution rate at brick SNP sites over expected values. In addition, contrary to typical brick mutations, brick variation commonly encountered in the human population displays limited, if any, signatures of negative selection as measured by the minor allele frequency and population differentiation (F-statistical measure) measures. These observations argue for the plasticity of gene regulatory mechanisms in vertebrates—with evidence of strong purifying selection acting on the gene regulatory landscape of the human genome, where widespread advantageous mutations in putative regulatory elements are likely utilized in functional diversification and adaptation of species.
Hirshfeld surfaces identify inadequacies in computations of intermolecular interactions in crystals: pentamorphic 1,8-dihydroxyanthraquinone

Fingerprint plots of Hirshfeld surfaces were used to locate and analyze the deficiencies in various methodologies employed in the determination of the relative energies of five polymorphs of 1,8-dihydroxyanthraquinone. Nine crystallographically independent molecules were characterized by X-ray crystallography and Hirshfeld surfaces were derived from the X-ray structures. The space groups and number of independent molecules (Z′) for each of the polymorphs (1−5) is as follows: (1) P41 (or P43),Z′ = 1; (2) Pca21, Z′ = 2; (3) P1, Z′ = 4; (4) P21/n, Z′ = 1; (5) P41212 (or P43212), Z′ = 0.5. Form 1 is the most thermodynamically stable among the reproducible structures, as established by competitive solubility tests, followed by 2 and then 4. The unrestrained structures of the five polymorphs were computed using the CVFF and COMPASS force fields as well as with the density functional code, SIESTA.
Admissible stochastic complexity models for classification problems

In this paper we investigate the application of stochastic complexity theory to classification problems. In particular, we define the notion of admissible models as a function of problem complexity, the number of data pointsN, and prior belief. This allows us to derive general bounds relating classifier complexity with data-dependent parameters such as sample size, class entropy and the optimal Bayes error rate. We discuss the application of these results to a variety of problems, including decision tree classifiers, Markov models for image segmentation, and feedforward multilayer neural network classifiers.
Internet 2 Commons: a collaborative environment

Partnerships among the educational community provide the substance and catalyst for future generations of teachers and students. The Internet 2 Commons provides a collaboration framework for the advancement of research and education. This effort incorporates technological advancements in support of research and pedagogical activities. Available to Internet 2 members are advanced networking and application services, which include collaborative data services and videoconferencing.
Effect of Pressure on the Optical Rotatory Power and Dispersion of α-Quartz

The effect of pressure on the optical rotatory power and dispersion has been investigated on single crystals of α-quartz over a pressure range of 3.5 kbar in the visible region of the spectrum. The optical rotatory power is found to decrease linearly with pressure with the magnitude of dρ/dP increasing with decreasing wavelengths. These results are shown to be in accordance with the pressure variation of a single-term quadratic dispersion equation.
Variational mechanics analysis of stresses and failure in microdrop debond specimens

Abstract A recently derived variational mechanics analysis of stresses in embedded single fibers has been applied to the analysis of the stresses in a microdrop debond specimen. The new analysis is more accurate than the commonly applied shear-lag or elastic-plastic analyses. The results from a sample stress state calculation suggest that interfacial failure between the fiber and the microdrop may be by mode I or opening-mode failure at the beginning of the microdrop. The opening-mode failure is caused by a large tensile radial stress at the fiber/matrix interface. Previous analyses of microdrop debond data have been in terms of an average shear stress. We suggest that these analyses misrepresent microdrop debond results and recommend alternative failure analyses using energy release rate, average energy, or maximum stress. The energy failure analyses can be used to define an interfacial fracture toughness.
Collagen XVIII Is a Basement Membrane Heparan Sulfate Proteoglycan

The present study shows that collagen XVIII is, next to perlecan and agrin, the third basal lamina heparan sulfate proteoglycan (HSPG) and the first collagen/proteoglycan with heparan sulfate side chains. By using monoclonal antibodies to an unidentified HSPG in chick, 14 cDNA clones were isolated from a chick yolk sac library. All clones had a common nucleotide sequence that was homologous to the mRNA sequences of mouse and human collagen XVIII. The deduced amino acid sequence of the chick fragment shows an 83% overall homology with the human and mouse collagen XVIII. Similar to the human and mouse homologue, the chick collagen XVIII mRNA has a size of 4.5 kilobase pairs. In Western blots, collagen XVIII appeared as a smear with a molecular mass of 300 kDa. After treatment with heparitinase, the protein was reduced in molecular mass by 120 kDa to a protein core of 180 kDa. Collagen XVIII has typical features of a collagen, such as its existence, under non-denaturing conditions, as a non-covalently linked oligomer, and a sensitivity of the core protein to collagenase digestion. It also has characteristics of an HSPG, such as long heparitinase-sensitive carbohydrate chains and a highly negative net charge. Collagen XVIII is abundant in basal laminae of the retina, epidermis, pia, cardiac and striated muscle, kidney, blood vessels, and lung. In situ hybridization showed that the main expression of collagen XVIII HSPG in the chick embryo is in the kidney and the peripheral nervous system. As a substrate, collagen XVIII moderately promoted the adhesion of Schwann cells but had no such activity on peripheral nervous system neurons and axons.
Enhanced Design for Flip Chip Interconnects

Multichip and flip chip technology has become increasingly popular in the past years. It employs a series of chips flipped and connected through metallic bumps. A study for improving the performance of flip chip interconnects is recently presented by Ghouz and El-Sharawy for frequencies up to 50 GHz. In that study, the idea of staggering the signal line interconnect with respect to the ground plane bumps to reduce reflection and insertion loss is introduced. In this paper concentration is put on re-shaping the discontinuity region in order to provide a better impedance match between the CPW-motherboard and the CPW-chip, and thus reducing reflection at the input terminals. Several approaches are tested to accomplish lower return loss, among them, the use of bumps of different thickness located at different positions, the use of tilted bumps or "ramps", and the use of dielectric loading on the bumps. The results indicate that the performance of these flip chips is greatly enhanced and extended to frequencie...
Soluble HLA-I (s-HLA-I) synthesis in systemic lupus erythematosus

Our objective was to study a possible contribution of major histocompatibility complex (MHC) genes to soluble HLA-I synthesis in patients with systemic lupus erythematosus (SLE). Solid-phase enzyme-linked immunoassay (ELISA) was used to measure sHLA-I in the sera of 20 patients with SLE and 76 normal controls with known HLA phenotypes. Serial serum samples (n=108) from the above group of patients (n=19) were further investigated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting. Soluble HLA-I levels were abnormally higher in patients with SLE than normal controls (P<0.0002). No complete HLA haplotype has been identified to be correlated with high or low sHLA-I secretion. Only the sera of HLA-A23- or -A24- (splits of HLA-A9) positive individuals were found to contain high sHLA-I concentrations in both populations studied. The difference between sHLA-I of HLA-A24 patients (n=7) and HLA-A24 normal controls (n=19) was statistically highly significant (P<0.0079). The results suggest that HLA-A24 may confer additional risk of more severe disease expression in female patients with SLE. The data imply that SLE patients carrying 39-kDa sHLA-I have increased risk of developing renal disease. A higher prevalence of 35–37 kDa was observed in patients with mild disease. Interestingly, 44–46 kDa was the predominant molecular form of sHLA-I in SLE patients with lymphocytosis with no evidence of organ involvement. Notably, all these variations were not reflected by differences in HLA phenotypes, with the exception of HLA-A24-positive patients, in whom the 44–46-kDa form occurs consistently but not exclusively. In summary, the results show a genetic heterogeneity of SLE with MHC control of the expression of sHLA-I concentrations and possible involvement of disease-associated factors that might potentiate a specific sHLA-I molecule synthesis.
Simultaneous reconstruction of absorbed optical energy density and speed of sound distributions in photoacoustic computed tomography

An important and interesting question in photoacoustic computed tomography (PACT) is whether the absorbed optical energy density distribution, A(r), and the speed of sound distribution, c(r), can both be accurately determined from the measured photoacoustic data alone. However, in many cases c(r) is unknown or cannot be accurately estimated. Therefore, it would be practically beneficial if A(r) and c(r) can be jointly reconstructed from the measurements. In this work, we propose a reconstruction approach to the joint reconstruction of both properties in PACT.
Global Design and Building Practice: A Case Study of Hearst Headquarters, New York, NY

This paper describes aspects of "Global Design and Building Practice”, a research started at the Harvard University Graduate School of Design in 2002. The objective of this investigation is to provide design and building professionals and researchers with a better understanding of the impacts of globalization on practice. In this research, the impacts of globalization on practice are examined both in breadth and depth. Processes involve qualitative analyses of interviews with design and building professionals and researchers, quantitative analyses of project data, and in-depth case studies of recent and current "global building projects”, i.e. projects for which spatial extensity of actors extends beyond the local. This paper presents a diversified analytic framework of four distinct global project types. It analyzes the principles behind the transformation of practice and demonstrates the correlations between different global project types and the impacts on practice based on "project DNA”, an innovative concept that acknowledges that it is not only the characteristics of each configuring actor that matters in a global project, but rather the configuration as a whole and the position of each actor within it that determines the its characteristics and impacts on practice. Both global project type and project DNA are illustrated with the summary of an in-depth case study of Hearst Headquarters, a recently completed global project in New York, NY.
The role of crystallization kinetics in the development of the structure and properties of polypropylene filaments

The processing, structure, and properties of filaments melt spun from three polypropylenes with similar rheology but substantially different crystallization kinetics were studied. The crystallization kinetics of the homopolymer was increased by the addition of a nucleating agent, whereas slower crystallization kinetics was obtained through a small amount of random copolymerization with ethylene. The relative crystallization kinetics of these three polymers was examined under quiescent conditions using differential scanning calorimetry. The technique of on-line diameter and birefringence measurement was used to show the characteristics of the on-line crystallization of the different resins. It was found that changing the quiescent crystallization kinetics by either the addition of a nucleating agent or through copolymerization with ethylene can produce profound effects on the structure and properties of polypropylene as-spun filaments when they are spun under relatively low stress and low takeup velocity conditions. Higher takeup velocities and spinline stresses reduce the effect of differences in quiescent crystallization due to the influence of on-line stress-induced (molecular orientation-enhanced) crystallization. © 1993 John Wiley & Sons, Inc.
Shock Layer Behavior for Vector Boundary Value Problems and Kinks in the Lower and Upper Solutions

Abstract We provide sufficient conditions for the existence and approximations of shock layer solutions of the weakly coupled boundary value problem ϵy′′ i =ƒ i (t, y)y′ i +g i (t, y) i=1, ..., n, yi(a)=Ai, yi(b)=Bi, where y, ƒ, and g are n-dimensional real-valued functions and yi, ƒi and gi are the respective vector components. ϵ is a small positive parameter. Our approach is based upon the construction of lower and upper "solutions" which have boundary layer behavior at specific points Ti (i=1, ..., n) in the interval a
Preservation of Channel Catfish Sperm

Abstract Three activators, eight extenders, and three protective agents at two concentration levels each were used to determine the best combination that will maintain in storage the viability of channel catfish (Ictalurus punctatus) sperm cells. There was a highly significant (P < 0.01) difference in motility score among activators. Saline (0.65%) gave the highest motility score. Extended sperm cells became motile when activated after 2 months of storage at 4 C. Extender I (Truscott and Idlers Hfx #1) with 10% dimethyl sulfoxide (DMSO) and 2 hours equilibration produced the highest motility scores after freezing of 24 hours or 1 week. Freezing rate was controlled by placing vials of sperm in a double-layered, kapok-lined paper bag and freezing at the height of 127 mm above the liquid nitrogen level.
A semiclassical limit for the mapping Hamiltonian approach to electronically nonadiabatic dynamics

In this paper we derive a semiclassical limit of dynamics corresponding to the mapping Hamiltonian formulation of the electronically nonadiabatic problem originally proposed by Stock and co-workers, and Miller and his group. We show results comparing the approach described here with the alternative semiclassical scheme previously used by these workers in applications of this formulation. For simplicity the calculations presented here are for single potential surface models but the approach is generally applicable to many coupled surfaces. We demonstrate by comparison with exact numerical solution that the results obtained with the approach presented here are accurate for arbitrary potential forms but that the alternative semiclassical implementation only apparently converges when repulsive walls in the model surfaces are unimportant.
A two-module region of the low-density lipoprotein receptor sufficient for formation of complexes with apolipoprotein E ligands.

The low-density lipoprotein (LDL) receptor transports two different classes of cholesterol-carrying lipoprotein particles into cells: LDL particles, which contain a single copy of apolipoprotein B-100 (apoB-100), and β-migrating very low-density lipoprotein (β-VLDL) particles, which contain multiple copies of apolipoprotein E (apoE). The ligand-binding domain of the receptor lies at its amino-terminal end within seven adjacent LDL-A repeats (LA1−LA7). Although prior work clearly establishes that LA5 is required for high-affinity binding of particles containing apolipoprotein E (apoE), the number of ligand-binding repeats sufficient to bind apoE ligands has not yet been determined. Similarly, uncertainty exists as to whether a single lipid-activated apoE receptor-binding site within a particle is capable of binding to the LDLR with high affinity or whether more than one is required. Here, we establish that the LA4−5 two-repeat pair is sufficient to bind apoE-containing ligands, on the basis of binding stu...
A Single Dose of the Selective Serotonin Reuptake Inhibitor Citalopram Exacerbates Anxiety in Humans: A Fear-Potentiated Startle Study

Serotonin reuptake inhibitors may increase symptoms of anxiety immediately following treatment initiation. The present study examined whether acute citalopram increased fear-potentiated startle to predictable and/or unpredictable shocks in healthy subjects. Eighteen healthy subjects each received two treatments, placebo and 20 mg citalopram in a crossover design. Participants were exposed to three conditions including one in which predictable aversive shocks were signaled by a cue, a second in which unpredictable shocks were anticipated, and a third in which no shocks were administered. Changes in aversive states were investigated using acoustic startle stimuli. Citalopram did not affect baseline startle. However, the phasic startle potentiation to the threat cue in the predictable condition was robustly increased by acute citalopram. The sustained startle potentiation in the unpredictable conditions was also increased by citalopram, but only when the drug was given during the first session. These results indicate that a single dose of citalopram is not anxiogenic in itself, but can exacerbate the expression of fear and anxiety.
Interpreting expressive performance through listener judgments of musical tension.

This study examines listener judgments of musical tension for a recording of a Schubert song and its harmonic reduction. Continuous tension ratings collected in an experiment and quantitative descriptions of the piece’s musical features, include dynamics, pitch height, harmony, onset frequency, and tempo, were analyzed from two different angles. In the first part of the analysis, the different processing timescales for disparate features contributing to tension were explored through the optimization of a predictive tension model. The results revealed the optimal time windows for harmony were considerably longer (~22 s) than for any other feature (~1-4 s). In the second part of the analysis, tension ratings for the individual verses of the song and its harmonic reduction were examined and compared. The results showed that although the average tension ratings between verses were very similar, differences in how and when participants reported tension changes highlighted performance decisions made in the interpretation of the score, ambiguity in tension implications of the music, and the potential importance of contrast between verses and phrases. Analysis of the tension ratings for the harmonic reduction also provided a new perspective for better understanding how complex musical features inform listener tension judgments.
Morphology of Red Creek, Wyoming, an arid-region anastomosing channel system

Red Creek, in the Red Desert area of the Great Divide Basin, Wyoming, is an arid-region anastomosing stream. The narrow, deep, and sinuous main channel is flanked by anastomosing flood channels, or anabranches. Most anabranches are initiated at meander bends. The primary mechanism of anabranch initiation is avulsion during overbank floods. Anabranch enlargement occurs by headward erosion. Anabranches act as distributary channels during floods, when water and sediment from overbank flows are transported to and deposited on the floodplain via the anabranches. During periods of low discharges, the anabranches act as tributaries to the main channel, transporting runoff from the floodplain and surrounding hillslopes to the main channel of Red Creek. Aggradation is occurring in the main channel and on the floodplain throughout the study reach. Infilling of the main channel occurs primarily by lateral accretion, while the floodplain accretes vertically through deposition of overbank sediment from the main channel and anabranches. Infilling of the main channel may cause avulsion of the main channel into an anabranch. The abandoned main channel segment may then fill completely or act as an anabranch. Because lateral migration of channels is inhibited by the high cohesion of the silt and clay channel sediment, periodic avulsion is the primary form of lateral mobility in the system.
Wind-induced motion of tall buildings

Abstract Modern buildings designed such that their lateral drifts under statically applied wind loads are less than some fraction of building height, may vibrate excessively during winds and cause occupant discomfort. Methods are presented for evaluating the vibration characteristics of buildings using random vibration theory to relate the fluctuating wind forces to structural response. These methods can be used to evaluate serviceability or to plan wind tunnel tests of buildings.
Singular Vector Analysis for Atmospheric Chemical Transport Models

Abstract The singular vectors of a chemical transport model are the directions of maximum perturbation growth over a finite time interval. They have proved useful for the estimation of error growth, the initialization of ensemble forecasts, and the optimal placement of adaptive observations. The aim of this paper is to address computational aspects of singular vector analysis for atmospheric chemical transport models. The distinguishing feature of these models is the presence of stiff chemical interactions. A projection approach to preserve the symmetry of the tangent linear–adjoint operator for stiff systems is discussed, and extended to 3D chemical transport simulations. Numerical results are presented for a simulation of atmospheric pollution in East Asia in March 2001. The singular values and the structure of the singular vectors depend on the length of the simulation interval, the meteorological data, the location of the optimization region and the selection of optimization species, the choice of err...
Mechanism of action of the anticonvulsant felbamate: Opposing effects on N-methyl-D-aspartate and γ-aminobutyric acidA receptors

Felbamate is a promising new antiepileptic drug whose mechanism of action is unknown. In whole-cell voltage clamp recordings from cultured rat hippocampal neurons, clinically relevant concentrations of felbamate (0.1-3 mM) inhibited N-methyl-D-aspartate (NMDA) responses and potentiated gamma-aminobutyric acid (GABA) responses. Single-channel recordings indicated that the effect on NMDA responses occurred via a channel blocking mechanism. Felbamate is the first anticonvulsant drug with dual actions on excitatory (NMDA) and inhibitory (GABA) brain mechanisms. This unique combination of effects could account for felbamate's broad spectrum of anticonvulsant activity in animal seizure models and its distinctive clinical efficacy and safety profile.
Slip modes and partitioning of energy during dynamic frictional sliding between identical elastic–viscoplastic solids

The effect of plasticity on dynamic frictional sliding along an interface between two identical elastic–viscoplastic solids is analyzed. The configuration considered is the same as that in Coker et al. (J Mech Phys Solids 53:884–992, 2005) except that here plane strain analyses are carried out and bulk material plasticity is accounted for. The specimens have an initial compressive stress and are subject to shear loading imposed by edge impact near the interface. The material on each side of the interface is modeled as an isotropically hardening elastic–viscoplastic solid. The interface is characterized as having an elastic response together with a rate- and state-dependent frictional law for its inelastic response. Depending on bulk material properties, interface properties and loading conditions, frictional slip along the interface can propagate in a crack-like mode, a pulse-like mode or a train-of-pulses mode. Results are presented for the effect of material plasticity on the mode and speed of frictional slip propagation as well as for the partitioning of energy components between stored elastic energy, kinetic energy, plastic dissipation in the bulk and frictional dissipation along the interface. Some parameter studies are carried out to explore the effects of varying the interface elastic stiffness and the impact velocity.
The effects of impurities and gamma radiation on positron annihilation in phenanthrene

Abstract The effects of impurities and gamma radiation on positron annihilation in phenanthrene have been measured. The presence of impurities reduces the intensity, I 2 , of the long-lived component. Gamma irradiation produces the unexpected result that I 2 is increased rather than diminished.
Group regulation and social-emotional interactions observed in computer supported collaborative learning: Comparison between good vs. poor collaborators

This study explored what social interactions students exhibited during collaborative learning, and analyzed how the social interactions evolved in a computer-supported collaborative learning (CSCL) environment. Six groups (n = 28) from an undergraduate online course were observed during a semester. Students' interactions were analyzed in two perspectives: group regulation and socioemotional. Cluster analysis was conducted to identify collaboration patterns of the groups. The analysis identified three collaborator clusters: one good and two poor. The good collaborators (named Early Active Collaborator) demonstrated: (1) intensive interactions among group members in the early collaboration phase, (2) positive socio-emotional interactions continuously, and (3) adaptive selections of group regulatory behaviors. The others showed dormant interactions throughout the projects and least socio-emotional interactions (named Passive Task-oriented Collaborator) and did not coordinate group process in a timely manner (named Late Collaborator). Comparisons of the interaction pattern and instructor intervention were discussed.
Nonalcoholic Steatohepatitis Is the Second Leading Etiology of Liver Disease Among Adults Awaiting Liver Transplantation in the United States

Background & Aims Nonalcoholic steatohepatitis (NASH) has been predicted to become the leading indication for liver transplantation (LT) in the United States. However, few studies have evaluated changes in the etiology of liver diseases among patients awaiting LT, and none have focused on the effects of NASH on liver transplant waitlists in the United States. Methods We collected data from the United Network for Organ Sharing and Organ Procurement and Transplantation Network registry from 2004 through 2013, on liver transplant waitlist registrants with hepatitis C virus (HCV) infection, NASH, alcoholic liver disease (ALD), or a combination of HCV infection and ALD. We compared differences in survival within 90 days of registration (90-day survival) and probability of LT among patients with different diseases using Kaplan-Meier and multivariate logistic regression models. Results Between 2004 and 2013, new waitlist registrants with NASH increased by 170% (from 804 to 2174), with ALD increased by 45% (from 1400 to 2024), and with HCV increased by 14% (from 2887 to 3291); registrants with HCV and ALD decreased by 9% (from 880 to 803). In 2013, NASH became the second-leading disease among liver transplant waitlist registrants, after HCV. Patients with ALD had a significantly higher mean Model for End-Stage Liver Disease score at time of waitlist registration than other registrants. However, after multivariate adjustment, patients with ALD were less likely to die within 90 days when compared with patients with NASH (odds ratio [OR] = 0.77; 95% confidence interval [CI]: 0.67–0.89; P P P P Conclusions Based on data from US adult LT databases, since 2004 the number of adults with NASH awaiting LTs has almost tripled. However, patients with NASH are less likely to undergo LT and less likely to survive for 90 days on the waitlist than patients with HCV, ALD, or HCV and ALD.
Prevention and treatment of postmenopausal osteoporosis

Key content Osteoporotic fractures are associated with increased morbidity and mortality. Clinical history and bone densitometry can identify individuals at risk for osteoporotic fractures. Treatment is available to prevent and treat osteoporosis. Learning objectives Identify populations at risk for osteoporotic fractures. Make the diagnosis of osteoporosis. Decide appropriate treatment for the prevention or treatment of osteoporosis. Ethical issues Maximising health benefit while minimising financial implications.
Network motifs that recur across species, including gene regulatory and protein–protein interaction networks

Cellular molecules interact in complex ways, giving rise to a cell’s functional outcomes. Conscientious efforts have been made in recent years to better characterize these patterns of interactions. It has been learned that many of these interactions can be represented abstractly as a network and within a network there in many instances are network motifs. Network motifs are subgraphs that are statistically overrepresented within networks. To date, specific network motifs have been experimentally identified across various species and also within specific, intracellular networks; however, motifs that recur across species and major network types have not been systematically characterized. We reason that recurring network motifs could potentially have important implications and applications for toxicology and, in particular, toxicity testing. Therefore, the goal of this study was to determine the set of intracellular, network motifs found to recur across species of both gene regulatory and protein–protein interaction networks. We report the recurrence of 13 intracellular, network motifs across species. Ten recurring motifs were found across both protein–protein interaction networks and gene regulatory networks. The significant pair motif was found to recur only in gene regulatory networks. The diamond and one-way cycle reversible step motifs were found to recur only in protein–protein interaction networks. This study is the first formal review of recurring, intracellular network motifs across species. Within toxicology, combining our understanding of recurring motifs with mechanism and mode of action knowledge could result in more robust and efficient toxicity testing models. We are sure that our results will support research in applying network motifs to toxicity testing.
Cardiovascular disease, SCI and exercise: unique risks and focused countermeasures.

Purpose. To summarise the spinal cord injury (SCI) specific profile of three cardiovascular disease risk factors (CVD): fasting dyslipidaemia, postprandial lipidaemia and vascular inflammation and to summarise exercise prescriptions that may attenuate each.Method. NA.Results. NA.Conclusions. At least three CVD risk factors have unique profiles in the SCI population. Fasting dyslipidaemia is characterised in the SCI population by depressed HDL cholesterol and normal or low total cholesterol. In the post-prandial state, persons with SCI exhibit an exaggerated triglyceride rise and delayed clearance compared to non-disabled persons. Finally, vascular inflammation, as indexed by C-reactive protein, is markedly elevated in SCI. Exercise may improve each, although the specific prescriptions differs. Fasting dyslipidaemia responds to 8 weeks of moderate intensity aerobic exercise performed 5 days weekly for 30 min daily. Post-prandial lipaemia treatment requires daily moderate or vigorous aerobic exercise, as th...
Multiscale modeling of polystyrene in various environments

Abstract We develop a systematic multiscale modeling approach for understanding the dynamics of polystyrene in the melt and blended with polyisoprene. The dynamics of polystyrene chains at chain length of 15 monomer in both environments are investigated using both atomistic and mesoscale models. The dynamics of polystyrene with chain length of 30 monomers and longer are illustrated by mesoscale models. The iterative Boltzmann inversion (IBI) method is used to derive the mesoscale models based on the atomistic simulations. The polystyrene chains clearly show dynamical heterogeneity along the chain and among chains in both models. The reorientation of PS chains speeds up with the increase of PI in the blends. We observe the onset of phase separation in atomistic simulations of polyisoprene–polystyrene blends at chain length of 15 monomer, and find full phase separation using mesoscale models for blends with chain length of 30 and above. We show that phase separation cannot be achieved with simple mixing rules. The phase separation morphologies could be cylindrical or spherical depending on the concentration ratio of the two components. The densities of the blends and their temperature dependencies are characterized.