cssi/SciSciGPT-SciSciNet huggingface dataset:
IDENTIFYING ANOMALIES IN GRAVITATIONAL LENS TIME DELAYS

We examine the ability of gravitational lens time delays to reveal complex structure in lens potentials. In a previous paper, we predicted how the time delay between the bright pair of images in a "fold" lens scales with the image separation, for smooth lens potentials. Here we show that the proportionality constant increases with the quadrupole moment of the lens potential, and depends only weakly on the position of the source along the caustic. We use Monte Carlo simulations to determine the range of time delays that can be produced by realistic smooth lens models consisting of isothermal ellipsoid galaxies with tidal shear. We can then identify outliers as "time delay anomalies." We find evidence for anomalies in close image pairs in the cusp lenses RX J1131 – 1231 and B1422+231. The anomalies in RX J1131 – 1231 provide strong evidence for substructure in the lens potential, while at this point the apparent anomalies in B1422+231 mainly indicate that the time delay measurements need to be improved. We also find evidence for time delay anomalies in larger-separation image pairs in the fold lenses, B1608+656 and WFI 2033 – 4723, and the cusp lens RX J0911+0551. We suggest that these anomalies are caused by some combination of substructure and a complex lens environment. Finally, to assist future monitoring campaigns we use our smooth models with shear to predict the time delays for all known four-image lenses.
Deformation of F-purity and F-regularity

Abstract For a Noetherian local domain (R,m,K) , it is an open question whether strong F -regularity deforms. We provide an affirmative answer to this question when the canonical module satisfies certain additional assumptions. The techniques used here involve passing to a Gorenstein ring, using an anti-canonical cover.
Experimental study of natural convection in horizontal porous layers with multiple heat sources

The work presented here reveals several interesting conclusions about flow and heat transfer in a channel with injection at one wall. At low-blowing Reynolds numbers, the streamwise velocity profiles resemble Poiseuille flow. As the blowing increases, the profiles become more skewed with reduced velocity gradients at the injected wall. The pressure gradients along the channel decrease almost linearly with length, which reflects the increased pressure drop required to accelerate the injected fluid to the continually increasing velocities required by mass conservation. The constant property assumption used in this work allows the momentum and mass conservation equations to be solved independently of the energy equation. Similarity solutions to the boundary-layer approximation of the energy equation with viscous dissipation neglected were found for several values of the Reynolds and Peclet numbers. The effects of Reynolds number on these solutions are not strong. However, very significant effects of the Peclet numbers are found. At Peclet numbers much less than unity ordinary conduction effects dominate and the temperature profile was found to be linear across the channel. As blowing increases, the profiles become increasingly nonlinear, with the temperature gradients (heat transfer rates) at the blown wall becoming smaller. This behavior is similar to that of a boundary layer on a transpiration cooled wall. For Peclet numbers greater than 3, the conduction to the blown wall is small. The opposite behavior occurs at the impermeable wall where heat transfer rates continually increase with increased blowing. These results can be used to approximate the transfer processes in thermal protection systems using a wick containing an evaporation material. The results show that high-evaporation rates can reduce heating of the substructure. Further, the increased convection at the upper wall can also be effective at reducing radiative heat transfer to the wick.
Insider trading activity, tenure length, and managerial compensation

Abstract In this study, insider trading activity is used as part of a managerial compensation structure. The wage structure changes with the tenure duration of the insider. Managers with shorter tenure rely more on insider profits as part of their compensation. On the other hand, managers with longer tenure execute insider transactions with lower profits. Different measurements of insider profits using calendar day returns of insider transactions, holding period returns for different horizons, or weighted average cumulative abnormal returns for the executive all lead to the same conclusion. The results are robust to various well-known empirical models, such as the CAPM model, the Fama and French (1993) three factor model, or the Carhart (1997) four factor model. Insider trading profits have increased in recent years overall, especially after the Securities and Exchange Commission (SEC) implementation of Rule 10b5-1 in 2000. Therefore, the design of a wage schedule incorporating insider trading activity has become more relevant.
Normalization of QCD corrections in top quark decay

Abstract We discuss the effects of QCD corrections to the on-shell decay t → bW . We resolve the scale ambiguity using the Brodaky-Lepage-Mackenzie scheme, and find that the appropriate coupling constant is α s MS (0.122m t ) . The largest long distance contribution comes from the definition of the on-shell mass of the top quark. We note that QCD corrections to the electroweak ϱ parameter are extremely small when the ϱ parameter is expressed in terms of the top quark width.
Glycopolymer probes of signal transduction

Glycans are key participants in biological processes ranging from reproduction to cellular communication to infection. Revealing glycan roles and the underlying molecular mechanisms by which glycans manifest their function requires access to glycan derivatives that vary systematically. To this end, glycopolymers (polymers bearing pendant carbohydrates) have emerged as valuable glycan analogs. Because glycopolymers can readily be synthesized, their overall shape can be varied, and they can be altered systematically to dissect the structural features that underpin their activities. This review provides examples in which glycopolymers have been used to effect carbohydrate-mediated signal transduction. Our objective is to illustrate how these powerful tools can reveal the molecular mechanisms that underlie carbohydrate-mediated signal transduction.
Sigma models having supermanifolds as target spaces

We study a topological sigma-model (A-model) in the case when the target space is an (m 0|m 1)-dimensional supermanifold. We prove under certain conditions that such a model is equivalent to an A-model having an (m 0−m 1)-dimensional manifold as a target space. We use this result to prove that in the case when the target space of A-model is a complete intersection in a toric manifold, this A-model is equivalent to an A-model having a toric supermanifold as a target space.
Enzymes in organic synthesis: recent developments in aldol reactions and glycosylations

Carbohydrates have not been as accessible as other biomolecules such as proteins and nucleic acids and are the least exploited. As a result of their highly asymmetric and densely functionalized nature, carbohydrates are difficult to synthesize using conventional chemistry. Enzymatic synthesis, however, with its high selectivity and mild reaction conditions is very useful for the preparation of carbohydrates. This review gives a brief overview of recent developments in the application of enzymatic aldol reactions and glycosylations to carbohydrate synthesis.
Performance and Scalability Analysis of Teraflop-Scale Parallel Architectures Using Multidimensional Wavefront Applications

The authors develop a model for the parallel performance of algorithms that consist of concurrent, two-dimensional wavefronts implemented in a message-passing environment. The model, based on a LogGP machine parameterization, combines the separate contributions of computation and communication wavefronts. The authors validate the model on three important supercomputer systems, on up to 500 processors. They use data from a deterministic particle transport application taken from the ASCI workload, although the model is general to any wavefront algorithm implemented on a 2-D processor domain. They also use the validated model to make estimates of performance and scalability of wavefront algorithms on 100 TFLOPS computer systems expected to be in existence within the next decade as part of the ASCI program and elsewhere. In this context, the authors analyze two problem sizes. Their model shows that on the largest such problem (1 billion cells), interprocessor communication performance is not the bottleneck. Single-node efficiency is the dominant factor.
Synthesis and reactions of 3,3-difluoroallylphosphonates and 3,3-difluoroallyltriphenylphosphonium bromide

Abstract 3,3-Difluoroallyltriphenylphosphonium bromide (1) and 3,3-difluoroallylphosphonates, 2, have been prepared by the reaction of CH2CHCF2Br with phosphites or triphenylphosphine in good yield. Wittig reaction of 1 with aldehydes gave the corresponding dienes (ArCHCHCHCF2) 4; however, Wadsworth-Emmons reaction of 2 with aldehydes failed to produce the dienes.
Sport and the Sexually Abused Male Child.

Through feminist research in the study of sport, the issue of child sexual abuse has been driven onto the agenda of sports organisations, resulting in considerable practical reform (Brackenridge, 2001). However, the flip-side to this development is that the experience of sexually abused males has been largely ignored. In 1990, Struve claimed, ‘a growing number of clinicians who work with sexual abuse are discovering that males probably are sexually victimized just as frequently as females’ (p. 3). Despite research on the ‘sexually victimized’ male reaching back over the last 15 to 20 years, researchers in sport have, so far, largely ignored the issue of the sexual abuse of males. Certainly, there has been no in-depth treatment of the abuse of males and sport researchers, to date, have been driven by the ‘male perpetrator–female victim’ paradigm. This focus has influenced the type of research that has been conducted and has inadvertently contributed to the further silencing of the sexually abused male. Thi...
A Simpler Proof of Mirzakhani’s Simple Curve Asymptotics

Maryam Mirzakhani (in her doctoral dissertation) has proved the author’s conjecture that the number of simple closed curves of length bounded by L on a hyperbolic surface S is asymptotic to a constant times L d , where d is the dimension of the Teichmuller space of S. In this note we clarify and simplify Mirzakhani’s argument.
Phantom depth and flat base change

We prove that if f: (R, m) → (S, n) is a flat local homomorphism, S/mS is Cohen-Macaulay and F-injective, and R and S share a weak test element, then a tight closure analogue of the (standard) formula for depth and regular sequences across flat base change holds. As a corollary, it follows that phantom depth commutes with completion for excellent local rings. We give examples to show that the analogue does not hold for surjective base change.
QCD Sum Rules and Models for Generalized Parton Distributions

I use QCD sum rule ideas to construct models for generalized parton distributions. To this end, the perturbative parts of QCD sum rules for the pion and nucleon electromagnetic form factors are interpreted in terms of GPDs and two models are discussed. One of them takes the double Borel transform at adjusted value of the Borel parameter as a model for nonforward parton densities, and another is based on the local duality relation. Possible ways of improving these Ansaetze are briefly discussed.
From data to wisdom in the global and civilizational context the cognitive perspective

The purpose of this study is to define information, mainly in terms of cognition units. Among these units are recognized: data, information, concept, knowledge, and wisdom. Their impact upon the concept of wisdom is evaluated. Finally, the model of comprehensive wisdom is defined. Wisdom is defined in terms of the evolution of minds, from Basic and Whole, through Global to Universal. In conclusion, the wisdom of these minds is defined for each of eight current civilizations: Western, Eastern, Chinese, Japanese, Buddhist, Islamic, Hindu, and African.
2,7-bis-N,N-dimethylaminochalcogenoxanthen-9-ones via electrophilic cyclization with phosphorus oxychloride

The electrophilic cyclization of N,N-diethyl 4-N,N-(dimethylamino)-2-(3-N,N-dimethyldimethylaminophenylchalcogeno)benzamides 7 with POCl3 and triethylamine in CH2Cl2 or with POCl3 in acetonitrile gave excellent yields (77−97% in CH2Cl2, 73−77% in acetonitrile) of the corresponding 2,7-bis-N,N-dimethylaminochalcogenoxanthen-9-ones 6. 3-Methoxyphenylchalcogo-substituted benzamide derivatives were much less reactive toward POCl3 and phenylchalcogeno-substituted benzamide derivatives gave no reaction with POCl3 after 48 h.
The Baryon Census in a Multiphase Intergalactic Medium: 30% of the Baryons May Still Be Missing

Although galaxies, groups, and clusters contain {approx}10% of the baryons, many more reside in the photoionized and shocked-heated intergalactic medium (IGM) and in the circumgalactic medium (CGM). We update the baryon census in the (H I) Ly{alpha} forest and warm-hot IGM (WHIM) at 10{sup 5-6} K traced by O VI {lambda}1032, 1038 absorption. From Enzo cosmological simulations of heating, cooling, and metal transport, we improve the H I and O VI baryon surveys using spatially averaged corrections for metallicity (Z/Z {sub Sun }) and ionization fractions (f {sub HI}, f {sub OVI}). Statistically, the O VI correction product correlates with column density, (Z/Z {sub Sun })f {sub OVI} Almost-Equal-To (0.015)(N {sub OVI}/10{sup 14} cm{sup -2}){sup 0.70}, with an N {sub OVI}-weighted mean of 0.01, which doubles previous estimates of WHIM baryon content. We also update the Ly{alpha} forest contribution to baryon density out to z = 0.4, correcting for the (1 + z){sup 3} increase in absorber density, the (1 + z){sup 4.4} rise in photoionizing background, and cosmological proper length dl/dz. We find substantial baryon fractions in the photoionized Ly{alpha} forest (28% {+-} 11%) and WHIM traced by O VI and broad-Ly{alpha} absorbers (25% {+-} 8%). The collapsed phasemore » (galaxies, groups, clusters, CGM) contains 18% {+-} 4%, leaving an apparent baryon shortfall of 29% {+-} 13%. Our simulations suggest that {approx}15% reside in hotter WHIM (T {>=} 10{sup 6} K). Additional baryons could be detected in weaker Ly{alpha} and O VI absorbers. Further progress requires higher-precision baryon surveys of weak absorbers, down to minimum column densities N {sub HI} {>=} 10{sup 12.0} cm{sup -2}, N {sub OVI} {>=} 10{sup 12.5} cm{sup -2}, N {sub OVII} {>=} 10{sup 14.5} cm{sup -2}, using high signal-to-noise data from high-resolution UV and X-ray spectrographs.« less
Auditors' Evaluation of Evidence Obtained Through Management Inquiry: A Cascaded‐Inference Approach

This study uses the cascaded‐inference paradigm to investigate how auditors evaluate evidence received during management inquiry. Contrary to predictions made by cascaded‐inference theory, results indicate that auditors are relatively more sensitive to source‐related uncertainties than evidence‐related uncertainties when evaluating information provided by client management. In addition, management‐provided evidence has less impact on auditors' beliefs than on nonauditors' beliefs. Finally, results also suggest that, under certain conditions, auditors may fail to recognize the value of information received during management inquiry.
A Novel Aldol Condensation with 2-Methyl-4-pentenal and Its Application to an Improved Total Synthesis of Epothilone B.

The stabilization of the transition state through a favorable interaction between the double bond of 1 and the carbonyl group of 2 appears to be responsible for the high diastereoface selectivity of the aldol reaction. This key step in the highly concise total synthesis of epothilone B is followed by a Suzuki coupling to introduce the thiazole domain, a Noyori reduction to control the stereochemistry at C3, and a final macrolactonization (see reaction scheme). X=protecting group.
Gauge covariant fermion propagator in quenched, chirally symmetric quantum electrodynamics

Abstract We discuss the chirally symmetric solution of the massless, quenched, Dyson-Schwinger equation for the fermion propagator in three and four dimensions. The solutions are manifestly gauge covariant. We consider a gauge covariance constraint on the fermion-gauge-boson vertex, which motivates a vertex Ansatz that both satisfies the Ward identity when the fermion self-mass is zero and ensures gauge covariance of the fermion propagator.
The integration of ad hoc sensor and cellular networks for multi-class data transmission

This paper targets mobile telemedicine applications that can be supported using third generation (3G) cellular networks, to provide highly flexible medical services. On the other hand, large-scale Ad hoc Sensor Networks (ASN), when deployed among mobile patients who may carry different kinds of micro-sensors to measure ECG, blood pressure, basal temperature or other physiological data, can provide a dynamic data query architecture to allow the medical specialists to monitor patients at any place. So far very little research has been conducted to explore the possibility of integrating ASN with mobile telemedicine. In this paper: 1. we suggest an integrated architecture that takes advantage of the low cost mobile sensor networks and 3G cellular networks to support multimedia medical calls with differentiated Quality-of-Service (QoS) requirements. 2. We propose a low-energy, distributed, concentric-zone-based data query mechanism that has the advantages of both proactive and reactive ad hoc routing algorithms to collect medical results from large-scale mobile patients for medical specialists who use cellular network to report patient data to the medical center. 3. In order to minimize the ambulance wireless call-dropping rate, we adopt accurate resource reservation call admission control (CAC) scheme to allocate the necessary bandwidth in the destination cell. 4. In order to meet the QoS requirements of patients' wireless calls, we use dynamic guard channel CAC scheme to keep their handoff-call dropping rate below a certain threshold. We evaluate the validity of our schemes through simulations and analyze their performance. Our results clearly indicate the efficiency of the proposed CAC and sensor network query algorithms to meet the multimedia telemedicine QoS requirements.
Morphological Evolution in High-Redshift Radio Galaxies and the Formation of Giant Elliptical Galaxies*

We present deep near-infrared images of high-redshift radio galaxies (HzRGs) obtained with the near-infrared camera (NIRC) on the Keck I telescope. In most cases, the near-IR data sample rest wavelengths that are free of contamination from strong emission lines and at λrest > 4000 A, where older stellar populations, if present, might dominate the observed flux. At z > 3, the rest-frame optical morphologies generally have faint, large-scale (~50 kpc) emission surrounding multiple, ~10 kpc components. The brightest of these components are often aligned with the radio structures. These morphologies change dramatically at 2 3 HzRGs are similar to the total sizes and luminosities of normal radio-quiet star forming galaxies at z = 3-4. For objects where such data are available, our observations show that the line-free, near-IR colors of the z > 3 galaxies are very blue, consistent with models in which recent star formation dominates the observed light. Direct spectroscopic evidence for massive star formation in one of the z > 3 HzRGs exists (4C 41.17). Our results suggest that the z > 3 HzRGs evolve into much more massive systems than the radio-quiet galaxies and that they are qualitatively consistent with models in which massive galaxies form in hierarchical fashion through the merging of smaller star-forming systems. The presence of relatively luminous subcomponents along the radio axes of the z > 3 galaxies suggests a causal connection with the AGN. We compare the radio and near-IR sizes as a function of redshift and suggest that this parameter may be a measure of the degree to which the radio sources have induced star formation in the parent objects. We also discuss the Hubble diagram of radio galaxies, the possibility of a radio power dependence in the K-z relation, and its implications for radio galaxy formation. Finally, we present for the first time in published format basic radio and optical information on 3C 257 (z = 2.474), the highest redshift galaxy in the 3C sample and among the most powerful radio sources known.
Treatment of postoperative voiding dysfunction following incontinence surgery

Persistent postoperative voiding dysfunction is a known complication following female stress incontinence surgery. Although many variations on surgical technique exist, the most common cause remains attributable to hypersuspension of the urethra. The diagnosis of postoperative voiding dysfunction in this setting can be challenging due to the lack of standardized criteria and varied clinical presentation. Furthermore, patients can present with a wide spectrum of symptomatology, not merely incomplete bladder emptying or outright retention. The symptoms of urethral hypersuspension can range from purely bladder storage symptoms on one hand (frequency, urgency, or urge incontinence), to the more commonly recognized bladder emptying dysfunction on the other hand (incomplete emptying or frank urinary retention). Although most cases of mild postoperative voiding dysfunction appear to resolve with expectant management, a subset of patients clearly benefit from a sling incision or formal urethrolysis. This leads to prompt improvement or resolution of their postoperative bladder symptoms. The timing of surgery must be determined by the clinician’s judgment. However, experience would suggest that postoperative bladder symptoms that persist beyond 4 weeks rarely resolve spontaneously. Within the literature, there has been a paradigm shift toward earlier intervention. Indeed, there are some data to suggest that delayed time to urethrolysis can lead to irreversible bladder dysfunction.
ON THE SURVIVAL AND ABUNDANCE OF DISK-DOMINATED GALAXIES

We study the formation of disk-dominated galaxies in a Λ cold dark matter (ΛCDM) universe. Their existence is considered to be a challenge for the ΛCDM cosmology, because galaxy mergers isotropize stellar disks and trigger angular momentum transport in gas disks, thus fostering the formation of central stellar spheroids. Here, we postulate that the formation of stellar spheroids from gas-rich disks is controlled by two parameters that characterize galaxy mergers, the mass ratio of merging dark matter halos, and the virial velocity of the larger merging halo. We utilize merger histories generated from realizations of the cosmological density field to calculate the fraction of dark matter halos that have avoided spheroid formation, and compare the derived statistics with the spheroid occupation fractions in surveys of nearby galaxies. We find, for example, that the survival rate of disk-dominated galaxies in ΛCDM is just high enough to explain the observed fractional representation of disk-dominated galaxies in the universe if the only mergers which lead to central spheroid formation are those with mass ratios M 2/M 1 > 0.3 and virial velocities V vir,1 > 55kms–1. We discuss the physical origin of this criterion.
CONSTRAINING COSMOLOGY WITH HIGH-CONVERGENCE REGIONS IN WEAK LENSING SURVEYS

We propose to use a simple observable, the fractional area of hot spots in weak gravitational lensing mass maps, which are detected with high significance, to determine background cosmological parameters. Because these high-convergence regions are directly related to the physical nonlinear structures of the universe, they derive cosmological information mainly from the nonlinear regime of density fluctuations. We show that in combination with future cosmic microwave background anisotropy measurements, this method can place constraints on cosmological parameters that are comparable to those from the redshift distribution of galaxy cluster abundances. The main advantage of the statistic proposed in this paper is that projection effects, normally the main source of uncertainty when determining the presence and the mass of a galaxy cluster, here serve as a source of information.
Parity-violating electron-deuteron scattering

The longitudinal asymmetry due to Z{sup 0} exchange is calculated in quasi-elastic electron-deuteron scattering at momentum transfers {vert_bar}Q{sup 2}{vert_bar} {approx_equal} 0.1 GeV{sup 2} relevant for the SAMPLE experiment. The deuteron and pn scattering-state wave functions are obtained from solutions of a Schroedinger equation with the Argonne v{sub 18} potential. Electromagnetic and weak neutral one- and two-nucleon currents are included in the calculation. The two-nucleon currents of pion range are shown to be identical to those derived in Chiral Perturbation Theory. The results indicate that two-body contributions to the asymmetry are small ({approx_equal} 0.2%) around the quasi-elastic peak, but become relatively more significant ({approx_equal} 3%) in the high-energy wing of the quasi-elastic peak.
A New Look at the Binary Characteristics of Massive Stars

We constrain the properties of massive binaries by comparing radial velocity data on early-type stars in Cygnus OB2 with the expectations of Monte Carlo models. Our comparisons test several popular prescriptions for massive binary parameters. We explore a range of true binary fraction, F, a range of power-law slopes, ?, describing the distribution of companion masses between the limits qlow and 1, and a range of power-law slopes, ?, describing the distribution of orbital separations between the limits rin and rout. We also consider distributions of secondary masses described by a Miller-Scalo type IMF and by a two-component IMF that includes a substantial ``twin'' population with M2 M1. Several seemingly disparate prescriptions for massive binary characteristics can be reconciled by adopting carefully chosen values for F, rin, and rout. We show that binary fractions F < 0.7 are less probable than F ? 0.8 for reasonable choices of rin and rout. Thus, the true binary fraction is high. For F = 1.0 and a distribution of orbital separations near the canonical Opik's law distribution (i.e., flat; ? = 0), the power-law slope of the mass ratio distribution is ? = -0.6 to 0.0. For F 0.8, ? is somewhat larger, in the range -0.4 to 1.0. In any case, the secondary star mass function is inconsistent with a Miller-Scalo-like IMF unless the lower end is truncated below ~2-4 M?. In other words, massive stars preferentially have massive companions. The best-fitting models are described by a Salpeter or Miller-Scalo IMF for 60% of secondary star masses with the other ~40% of secondaries having M2 M1, i.e., twins. These model parameters simultaneously predict the fraction of Type Ib/c supernovae to be 30%-40% of all core-collapse supernovae, in agreement with recent observational estimates.
The Vlasov-Maxwell-Boltzmann System in the Whole Space

The Vlasov–Maxwell–Boltzmann system is one of the most fundamental models to describe the dynamics of dilute charged particles, where particles interact via collisions and through their self-consistent electromagnetic field. We prove existence of global in time classical solutions to the Cauchy problem near Maxwellians.
MTIS approach for DSS development: a case example

End-user systems development, and in specific decision support systems development, is one of the key factors for increasing productivity both in the end-user and in the mis department environment. It decreases the demand for traditional systems development projects, and provides faster response to user needs. The key factor to promote end-user systems development is the existence of friendly and 'MIS hygienic' end-user system development methodologies. In this paper a new approach for end-user systems development - Management Through Information Systems - is discussed, and a methodology for developing model oriented decision support systems using this approach is reviewed. Finally, a case for investment and price decisions is used as an example of DSS development using the MTIS approach, including implementation illustrations in Lotus 1-2-3.
The Strategy of Manipulating Conflict

Two decision-makers choose hawkish or dovish actions in a con‡ict game with incomplete information. The decision-making can be manipulated by “extremists” who send publicly observed cheaptalk messages. The power of extremists depends on the nature of the underlying con‡ict game. If actions are strategic complements, a “hawkish extremist” (provocateur) can increase the likelihood of con‡ict by sending messages which trigger a “fear-spiral”of hawkish actions. This reduces the welfare of both decision-makers. If actions are strategic substitutes, a “dovish extremist”(paci…st) can send messages which cause one decision-maker to back down and become more dovish. This reduces his welfare but bene…ts the other decision-maker. The hawkish extremist is unable to manipulate the decision-makers if actions are strategic substitutes, and the paci…st is equally powerless if actions are strategic complements.
Thalidomide ameliorates portal hypertension via nitric oxide synthase independent reduced systolic blood pressure.

AIM: Portal hypertension is a common complication of liver cirrhosis and significantly increases mortality and morbidity. Previous reports have suggested that the compound thalidomide attenuates portal hypertension (PHT). However, the mechanism for this action is not fully elucidated. One hypothesis is that thalidomide destabilizes tumor necrosis factor α (TNFα) mRNA and therefore diminishes TNFα induction of nitric oxide synthase (NOS) and the production of nitric oxide (NO). To examine this hypothesis, we utilized the murine partial portal vein ligation (PVL) PHT model in combination with endothelial or inducible NOS isoform gene knockout mice. METHODS: Wild type, inducible nitric oxide synthase (iNOS)-/- and endothelial nitric oxide synthase (eNOS)-/- mice received either PVL or sham surgery and were given either thalidomide or vehicle. Serum nitrate (total nitrate, NOx) was measured daily for 7 d as a surrogate of NO synthesis. Serum TNFα level was quantified by enzyme-linked immunosorbent assay. TNFα mRNA was quantified in liver and aorta tissue by reverse transcription-polymerase chain reaction. PHT was determined by recording splenic pulp pressure (SPP) and abdominal aortic flow after 0-7 d. Response to thalidomide was determined by measurement of SPP and mean arterial pressure (MAP). RESULTS: SPP, abdominal aortic flow (Qao) and plasma NOx were increased in wild type and iNOS-/- PVL mice when compared to sham operated control mice. In contrast, SPP, Qao and plasma NOx were not increased in eNOS-/- PVL mice when compared to sham controls. Serum TNFα level in both sham and PVL mice was below the detection limit of the commercial ELISA used. Therefore, the effect of thalidomide on serum TNFα levels was undetermined in wild type, eNOS-/- or iNOS-/- mice. Thalidomide acutely increased plasma NOx in wild type and eNOS-/- mice but not iNOS-/- mice. Moreover, thalidomide temporarily (0-90 min) decreased mean arterial pressure, SPP and Qao in wild type, eNOS-/- and iNOS-/- PVL mice, after which time levels returned to the respective baseline. CONCLUSION: Thalidomide does not reduce portal pressure in the murine PVL model by modulation of NO biosynthesis. Rather, thalidomide reduces PHT by decreasing MAP by an undetermined mechanism.
Subcooled convective boiling of binary mixtures over an array of heated elements

Boiling data and the critical heat flux conditions are reported for both channel flow and jet impingement flow using varying concentrations of R-ll in R-113. An array of 10 flush-mounted heated elements on one wall of a vertical passage was cooled by subcooled boiling. Data indicate that for channel flow boiling, the addition of R-ll to R-113 does not produce a significant change in the critical heat flux condition. For channel flow boiling, the data indicate that addition of a small amount of a less volatile component slightly increased the critical heat flux, whereas, the addition of a small amount of a more volatile component decreased it. The critical heat flux data for channel flow were also found to agree well with critical heat flux correlations for pure fluids if the mole-weighted mean properties of the mixture were used to compute the critical heat flux from the pure fluid correlation. However, for jet impingement flow with binary mixtures, deviations existed between measured data and pure fluid correlation predictions using mole-weighted mean properties of the mixture. The significance of the findings of this study with regard to the use of binary mixtures of dielectric fluids for immersion cooling of electronic components is discussed in this article.
Halo Cores and Phase-Space Densities: Observational Constraints on Dark Matter Physics and Structure Formation

We explore observed trends in the cores of a wide range of relaxed dark matter-dominated halos (about 7 orders of magnitude in mass) to constrain hypothetical dark matter candidates and scenarios of structure formation. First, we argue that neither generic warm dark matter (collisionless or collisional) nor self-interacting dark matter can be responsible for the observed cores on all scales. Both scenarios predict smaller cores for higher mass systems, in conflict with observations; some cores must instead have a dynamical origin. Second, we show that the mean core phase-space densities Q of dwarf spheroidal galaxies, rotating dwarf and low surface brightness galaxies, and clusters of galaxies decrease with increasing velocity dispersion like Q ∝ σ-3 ∝ M-1, as predicted by a simple scaling argument based on quietly merging equilibrium systems over a range of about 8 orders of magnitude in Q. We discuss the processes that set the overall normalization of the observed phase density hierarchy. We note the resemblance between the observed phase-space scaling behavior and density profiles of dark matter halos and stellar components in elliptical galaxies and conjecture that dark matter halos may suffer from the same systematic departures from homology as seen in elliptical galaxies, thus explaining the shallower density profiles observed in low-mass halos. Finally, we use the maximum observed phase-space density in dwarf spheroidal galaxies to fix a minimum mass for relativistically decoupled warm dark matter candidates of roughly 700 eV for thermal fermions and 300 eV for degenerate fermions.
Understanding Interorganizational Cooperation: Public-Private Collaboration in Regulating Financial Market Innovation

This paper examines how a collaborative effort between the private and public sectors, called the Derivatives Policy Group (DPG), helped shape current regulation of financial innovation. In 1994 and 1995, this group of six large financial firms developed procedures for risk management, internal controls, and reporting for largely unregulated areas of finance, in cooperation with the United States Securities and Exchange Commission and Commodity Futures Trading Commission. The process succeeded despite strong competition among the firms themselves and incentives for both the public and private sectors to resort to adversarial lobbying and legal challenges. The Derivatives Policy Group was a path-setting event in the development of flexible regulation of financial innovation that is now the norm for related policy making.The case is important in and of itself--the financial markets are a major concern of national and international economic policy--but here we treat it as an instance of a larger class of problems. Organizational science constantly encounters settings that involve numerous participants who compete or have histories of conflicts; who are interdependent, and collectively would gain (and even individually gain long term) by cooperating rather than competing on an issue; who fall under different governance systems; and who try as a group to design rules and principles governing their behavior. Four factors appear repeatedly in the research on the success or failure of such arrangements. These are (1) the initial dispositions toward cooperation, (2) the extant issues and incentives, (3) leadership, and (4) the number and variety of organizations involved. This paper focuses on how these factors shaped the development and consequences of the Derivatives Policy Group, and the general implications of this process for interorganizational cooperation.
The U-Band Galaxy Luminosity Function of Nearby Clusters

Despite the great potential of the U-band galaxy luminosity function (GLF) to constrain the history of star formation in clusters, to clarify the question of variations of the GLF across filter bands, to provide a baseline for comparisons to high-redshift studies of the cluster GLF, and to estimate the contribution of bound systems of galaxies to the extragalactic near-UV background, determinations have so far been hampered by the generally low efficiency of detectors in the U band and by the difficulty of constructing both deep and wide surveys. In this paper we present U-band GLFs of three nearby, rich clusters to a limit of MU ≈ -17.5 (M + 2). Our analysis is based on a combination of separate spectroscopic and R- and U-band photometric surveys. For this purpose, we have developed a new maximum likelihood algorithm for calculating the LF that is particularly useful for reconstructing the galaxy distribution function in multidimensional spaces (e.g., the number of galaxies as a simultaneous function of luminosity in different filter bands, surface brightness, star formation rate, morphology, etc.) because it requires no prior assumptions as to the shape of the distribution function. The composite LF can be described by a Schechter function with characteristic magnitude M = -19.82 ± 0.27 and faint-end slope αU = -1.09 ± 0.18. The total U-band GLF is slightly steeper than the R-band GLF, indicating that cluster galaxies are bluer at fainter magnitudes. Quiescent galaxies dominate the cumulative U-band flux for MU < -14. The contribution of galaxies in nearby clusters to the U-band extragalactic background is less than 1% Gyr-1 for clusters of masses ~3 × 1014-2 × 1015 M☉.
GLYCOSYLATION REACTIONS OF 6-NITRO-1,3-DIDEAZAPURINE AND 6-NITRO-1-DEAZAPURINE

Abstract In glycosylations utilizing SnCl 4 activation or S N 2 displacement of the α-chlorosugar, two closely related purines, namely 6-nitro-1,3-dideazapurine 1 and 6-nitro-1-deazapurine 2 , give different distributions of isomeric products.
Isolation of highly malignant Thy-1-positive revertants from cultured cloned Thy-1-negative lymphoma cells of low tumorigenicity

We have used a positive immunoselection method to isolate a Thy-1-positive revertant of a Thy-1-negative line. The technique makes use of the ability of surface bound antigen-antibody complexes containing the enzyme catalase to protect cells from the toxic effects of hydrogen peroxide. The revertant cells produce a Thy-1 molecule indistinguishable from that produced by the original parent line, and they resemble that line in being far more tumorigenic than the Thy-1-negative variant.
Relationship between Amazon and high Andes rainfall

[1] A regional climate model is used to study the connections between Amazon and high Andes rainfall. The modeling effort focuses on understanding the rainfall response during the Last Glacial Maximum (LGM) (∼21,000 years ago), as paleoproxy evidence generally suggests that the high Andes were wet during this period, while conditions over the Amazon were drier, although there is more uncertainty about the latter. Analysis of the yearlong present-day and full LGM integrations reveals that the delayed onset of Amazon convection in the LGM during austral spring is associated with an enhancement of rainfall over the high Andes. In the absence of convection over the Amazon in the austral spring, zonal geopotential height gradients over the Amazon strengthen, resulting in anomalous easterly flow between the Amazon and the high Andes. Instead of the low-level flow paralleling the Andes (e.g., northwesterly), the flow impinges more directly onto the eastern slopes of the Andes during the LGM, where it rises and transports moisture from the Amazon up into the mountains, enhancing convection over the Andes. This circulation mechanism explains how the moisture and rainfall over the high Andes of Peru and Bolivia can increase (such as the case for the LGM) despite large-scale drying over South America. Present-day observations are then explored for 1984, 2002, and 2003 to identify whether mechanisms identified in the paleoclimate modeling are observable in the present-day climate. Comparison of these particular springs reveals a response analogous to the LGM model response, suggesting that this mechanism that connects tropical Atlantic sea surface temperatures/Amazon convection and high Andes rainfall is operating in the present climate.
Thrombin: A paradigm for enzymes allosterically activated by monovalent cations

Enzymes activated by monovalent cations are abundantly represented in plants and the animal world. The mechanism of activation involves formation of a ternary intermediate with the enzymesubstrate complex, or binding of the cation to an allosteric site in the protein. Thrombin is a Na+-activated enzyme with procoagulant, anticoagulant and signaling roles. The binding of Na+ influences allosterically thrombin function and offers a paradigm for regulatory control of protease activity and specificity. Here we review the molecular basis of thrombin allostery as recently emerged from mutagenesis and structural studies. The role of Na+ in blood coagulation and the evolution of serine proteases are also discussed.
The shape of galaxy cluster dark matter haloes: systematics of its imprint on cluster gas and comparison to observations

We study predictions for galaxy cluster observables that can test the statistics of dark matter halo shapes expected in a flatCDM universe. We present a simple analytical model for the prediction of cluster-scale X-ray observations, approximating clusters as isothermal systems in hydrostatic equilibrium, and dark matter haloes as ellipsoids with uniform axial ratios (homeoidal ellipsoids). We test the model against high- resolution, hydrodynamic cluster simulations to gauge its reliability. We find that this simple prescription does a good job of predicting cluster X-ray ellipticities compared to the simulations as long as one focuses on cluster regions that are less sensitive to recent mergers. Based on this simple model, the distribution of cluster-size halo shapes expected in the concordanceCDM cosmology implies an X-ray ellipticity distribution with a mean h ǫX i = 0.32 ± 0.01, and a scatter σǫ = 0.14 ± 0.01 for the mass range (1 − 4) × 10 14 h −1 M⊙. We find it important to include the mass dependence of halo shape when making comparisons to observational samples that contain many, very massive clusters. We analyse the systematics of four observational samples of cluster ellipticities and find that our results are statistically compatible with observations. In particular, we find remarkably good agreement between two recent ROSAT samples andCDM predictions that do not include gas cooling. We also test how well our analytical model can predict Sunyaev-Zel'dovich decrement maps and find that it is less successful although still useful; the model does not perform as well as a function of flux level in this case because of the changing triaxiality of dark matter haloes as a function of radial distance. Both this effect and the changing alignment of isodensity shells of dark matter haloes leave an imprint on cluster gas that appears to be seen in observational data. Thus, dark matter haloes cannot be accurately characterized as homeoidal ellipsoids for all comparisons.
High-speed visible light indoor networks based on optical orthogonal codes and combinatorial designs

Interconnecting devices in an indoor environment using the illumination system and white light emitting diodes (LED) requires adaptive networking techniques that can provide network access for multiple users. Two techniques based on multilevel signaling and optical orthogonal codes (OOC) are explored in this paper in order to provide simultaneous multiple access in an indoor multiuser network. Balanced incomplete block designs (BIBD) are used to construct multilevel symbols for M-ary signaling. Using these multilevel symbols we are able to control the optical peak to average power ratio (PAPR) in the system, and hereby control the dimming level. In the first technique, the M-ary data of each user is first encoded using the OOC codeword that is assigned to that user, and then it is fed into a BIBD encoder to generate a multilevel signal. The second multiple access method uses sub-sets of a BIBD code to apply multilevel expurgated pulse-position modulation (MEPPM) [1] to the data of each user. While the first approach has a larger Hamming distance between the symbols of each user, the latter can provide higher bit-rates for users in VLC systems with bandwidth-limited LEDs.
Automatic input for business data-processing systems

Synopsis: Computers for business applications are generally input limited and require excessive manpower for data preparation. This can be reduced, and gains can be made in speed and reliability if the data forms for the computer and the human being are compatible. Documents must be prepared for manual use in conjunction with many phases of automatic business or technical data handling, and such documents with suitable format arrangements can be fed directly to the computer input with the techniques described. The numbers and symbols on the document are printed in magnetic ink in conventional form and size, and machine reading can be accomplished at rates exceeding 5,000 characters per second. The documents themselves have been handled at rates up to 50 per second.
Flattening Scientific CCD Imaging Data with a Dome Flat-Field System

We describe the flattening of scientific CCD imaging data using a dome flat-field system. The system uses light emitting diodes (LEDs) to illuminate a carefully constructed dome flat-field screen. LEDs have several advantages over more traditional illumination sources: they are available in a wide range of output wavelengths, are inexpensive, have a very long source lifetime, and are straightforward to control digitally. The circular dome screen is made of a material with Lambertian scattering properties that efficiently reflects light of a wide range of wavelengths and incident angles. In this paper, we compare flat fields obtained using this system with two types of traditionally-constructed flat fields: twilight sky flats and nighttime sky flats. Using photometric standard stars as illumination sources, we test the quality of each flat field by applying it to a set of standard star observations. We find that the dome flat-field system produces flat fields that are superior to twilight or nighttime sky flats, particularly for photometric calibration. We note that a ratio of the twilight sky flat to the nighttime sky flat is flat to within the expected uncertainty; but since both of these flat fields are inferior to the dome flat, this common test is not an appropriate metric for testing a flat field. Rather, the only feasible and correct method for determining the appropriateness of a flat field is to use standard stars to measure the reproducibility of known magnitudes across the detector.