cssi/SciSciGPT-SciSciNet huggingface dataset:
Heegaard Floer homology and several families of Brieskorn spheres

Abstract In Ozsvath and Szabo (2003) [15] the authors gave a combinatorial description for the Heegaard Floer homology of boundaries of certain negative-definite plumbings. Nemethi constructed a remarkable algorithm in Nemethi (2005) [12] for executing these computations for almost-rational plumbings, and his work in Nemethi (2007) [13] gives a formula computing the invariants for the Brieskorn homology spheres − Σ ( p , q , p q n + 1 ) . Here we give a formula for HF + ( − Σ ( p , q , p q n − 1 ) ) , generalizing the one for the n = 1 case given in Borodzik and Nemethi (2011) [3] . We also compute HF + for the families − Σ ( 2 , 5 , k ) and − Σ ( 2 , 7 , k ) .
CESSATION OF X-RAY PULSATION OF GX 1+4

We report results from our weekly monitoring campaign on the X-ray pulsar GX 1+4 with the Rossi X-Ray Timing Explorer satellite. The spin-down trend of GX 1+4 was continuing, with the pulsar being at its longest period ever measured (about 138.7 s). At the late stage of the campaign, the source entered an extended faint state, during which its X-ray (2-60 keV) flux decreased significantly, to an average level of ~3 × 10-10 ergs cm-2 s-1. It was highly variable in the faint state; the flux dropped to as low as ~3 × 10-11 ergs cm-2 s-1. In several observations during this period, the X-ray pulsation became undetectable. We can therefore conservatively conclude that the pulsed fraction, which is normally 70% (peak-to-peak), must have decreased drastically in those cases. This is very similar to what was observed in GX 1+4 in 1996, when it became similarly faint in X-ray. In fact, the flux at which the cessation of X-ray pulsation first occurred is nearly the same as it was in 1996. We suggest that we have once again observed the propeller effect in GX 1+4, a phenomenon that is predicted by theoretical models of accreting X-ray pulsars.
A Unified Analysis of Paging and Caching

Paging (caching) is the problem of managing a two-level memory hierarchy in order to minimize the time required to process a sequence of memory accesses. In order to measure this quantity, which we refer to as the total memory access time, we define the system parameter miss penalty to represent the extra time required to access slow memory. We also introduce the system parameter page size. In the context of paging, miss penalty is quite large, so most previous studies of on-line paging have implicitly set miss penalty =∞ in order to simplify the model. We show that this seemingly insignificant simplification substantially alters the precision of derived results. For example, previous studies have essentially ignored page size. Consequently, we reintroduce the miss penalty and page size parameters to the paging problem and present a more accurate analysis of on-line paging (and caching). We validate using this more accurate model by deriving intuitively appealing results for the paging problem which cannot be derived using the simplified model. First, we present a natural, quantifiable definition of the amount of locality of reference in any access sequence. We also point out that the amount of locality of reference in an access sequence should depend on page size among other factors. We then show that deterministic and randomized marking algorithms such as the popular least recently used (LRU) algorithm achieve constant competitive ratios when processing typical access sequences which exhibit significant locality of reference; this represents the first competitive analysis result which (partially) explains why LRU performs as well as it is observed to in practice. Next, we show that finite lookahead can be used to obtain algorithms with improved competitive ratios. In particular, we prove that modified marking algorithms with sufficient lookahead achieve competitive ratios of 2. This is in stark contrast to the simplified model where lookahead cannot be used to obtain algorithms with improved competitive ratios. We conclude by using competitive analysis to evaluate the benefits of increasing associativity in caches. We accomplish this by specifying an algorithm and varying the system configuration rather than the usual process of specifying the system configuration and varying the algorithm.
The determination of the CKM matrix

Abstract A general discussion of the Cabibbo–Kobayashi–Maskawa (CKM) matrix is given and the importance stressed of determining the matrix elements as an essential part of understanding CP violation in and beyond the Standard Model. The status of knowledge of the matrix elements connecting the first and second generation quarks is reviewed. A perspective on determinations of the full CKM matrix is presented as an introduction to the separate contributions to the panel discussion that follows.
Catalytic Asymmetric Allylation of Ketones and a Tandem Asymmetric Allylation/Diastereoselective Epoxidation of Cyclic Enones

A simple procedure is reported for the catalytic asymmetric allylation of ketones, utilizing titanium tetraisopropoxide, BINOL, 2-propanol additive, and tetraallylstannane as allylating agent. A variety of ketone substrates, including acetophenone derivatives and alpha,beta-unsaturated cyclic enones, reacted to form tertiary homoallylic alcohols in good yields (67-99%) and with high levels of enantioselectivity (generally >80%). A novel one-pot enantioselective allylation/diastereoselective epoxidation has also been introduced. Thus, upon completion of the allyl addition to conjugated cyclic enones, 1 equiv of tert-butyl hydroperoxide is added and the directed epoxidation of the allylic double bond ensues to afford the epoxy alcohol with high diastereoselectivity.
The Astrometric-Spectroscopic Binary System HIP 50796: An Overmassive Companion

We report spectroscopic observations of the star HIP 50796, previously considered (but later rejected) as a candidate member of the TW Hya association. Our measurements reveal it to be a single-lined binary with an orbital period of 570 days and an eccentricity of e = 0.61. The astrometric signature of this orbit was previously detected by Hipparcos in the form of curvature in the proper-motion components, although the period was unknown at the time. By combining our radial velocity measurements with the Hipparcos intermediate data (abscissa residuals) we are able to derive the full three-dimensional orbit and determine the dynamical mass of the unseen companion, as well as a revised trigonometric parallax that accounts for the orbital motion. Given our primary mass estimate of 0.73 M⊙ (mid-K dwarf), the companion mass is determined to be 0.89 M⊙, or ~20% larger than the primary. The likely explanation for the larger mass without any apparent contribution to the light is that the companion is itself a closer binary composed of M dwarfs. The near-infrared excess and X-ray emission displayed by HIP 50796 support this. Our photometric modeling of the excess leads to a lower limit to the mass ratio of the close binary of q ~ 0.8 and individual masses of 0.44-0.48 and 0.41-0.44 M⊙. The new parallax (π = 20.6 ± 1.9 mas) is significantly smaller than the original Hipparcos value and more precise.
Review and Recommended Experimental Procedures For Evaluation Of Abrupt Wing Stall Characteristics

Ar eview of the experimental program for four different aircraft configurations conducted as part of the Abrupt Wing Stall Program has been made. Several candidate figures of merit from conventional static-tunnel tests are summarized and correlated with data obtained in unique free-to-roll tests. The conclusion from this study is that these figures of merit can by themselves give some indication as to whether an aircraft would experience uncommanded lateral activity caused by abrupt wing stall. However, no one specific figure of merit consistently flagged a warning of potential lateral activity when actual activity was seen to occur in the free-to-roll experiments. In fact, they yielded as many or more false indications of lateral activity then were seen in the free-to-roll response data. Excellent agreement between free-to-roll results and flight was obtained for those configurations where flight data were available.
The influence of laminar separation and transition on low Reynolds number airfoil hysteresis

An experimental study of the Lissaman 7769 and Miley MO6-13-128 airfoils at low chord Reynolds numbers is presented. Although both airfoils perform well near their design Reynolds number of about 600,000, they each produce a different type of hysteresis loop in the lift and drag forces when operated below chord Reynolds numbers of 300,000. The type of hysteresis loop was found to depend upon the relative location of laminar separation and transition. The influence of disturbance environment and experimental procedure on the low Reynolds number airfoil boundary layer behavior is also presented. The use of potential flow solutions to help predict how a given airfoil will behave at low Reynolds numbers is also discussed.
Experiments with trapped hydrogen atoms and neutrons

The earliest trapped atom coherent resonance experiments were with material traps or bottles. In the atomic hydrogen maser the atoms are trapped inside a teflon-coated quartz bulb for about a second. Neutrons have been trapped for hundreds of seconds in suitably coated bottles or in superconducting magnetic traps. Results from experiments with trapped atoms and neutrons are given.
Synthesis of 4,6-difluoro-5-hydroxy-(α-methyl)tryptamine and 4,6-difluoro-5-hydroxy-(β-methyl)tryptamine as potential selective monoamine oxidase B inhibitors

Abstract Condensation of 4-nitro-1-pentanal and 4-nitropentanal 3-methylbutanal with 3,5-difluoro-4-methoxyphenylhydrazine afforded 4,6-difluoro-5-methoxy-3-(2′-nitro)propylindole 4a and 4,6-difluoro-5-methoxy-3-(1′-methyl-2′-nitro)ethylindole 4b , respectively, in one step. Reduction of the nitro group with lithium aluminum hydride followed by removal of the methyl ether with boron tribromide produced the title compounds. They were inactive as MAO B inhibitors.
From necklace quivers to the F -theorem, operator counting, and T (U(N))

The matrix model of Kapustin, Willett, and Yaakov is a powerful tool for exploring the properties of strongly interacting superconformal Chern-Simons theories in 2+1 dimensions. In this paper, we use this matrix model to study necklace quiver gauge theories with $ \mathcal{N} = {3} $ supersymmetry and U(N) d gauge groups in the limit of large N. In its simplest application, the matrix model computes the free energy of the gauge theory on S 3. The conjectured F -theorem states that this quantity should decrease under renormalization group flow. We show that for a simple class of such flows, the F -theorem holds for our necklace theories. We also provide a relationship between matrix model eigenvalue distributions and numbers of chiral operators that we conjecture holds more generally. Through the AdS/CFT correspondence, there is therefore a natural dual geometric interpretation of the matrix model saddle point in terms of volumes of 7-d tri-Sasaki Einstein spaces and some of their 5-d submanifolds. As a final bonus, our analysis gives us the partition function of the T (U(N)) theory on S 3.
Modeling of microdischarge devices: Pyramidal structures

Microdischarge (MD) devices are plasma sources typically operating at 100s Torr to atmospheric pressure with dimensions of 10s–100s μm. Their design in based on pd (pressure×characteristic dimension) scaling; smaller dimensions are enabled by higher operating pressures with typical devices operating with pd=1–10 Torr cm. MD devices have exhibited behavior that resemble both Townsend and hollow-cathode discharges, with bulk and beam electrons providing the dominant excitation, respectively. In this article, results from a two-dimensional computational study of MD devices operating in neon using a pyramidal cathode structure are discussed. Pressures of 400–1000 Torr and device dimensions of 15–40 μm are investigated. The onset of behavior resembling negative glow discharges with decreasing pressure correlates with an extension of cathode fall accelerated beam electrons into the bulk plasma. For constant applied voltage, peak electron densities increase with increasing pressure as the beam electrons are slowed in more confined regions. The MD devices typically require higher applied voltages to operate at lower pressures, and so resemble discharges obeying Paschen’s curve for breakdown. MD devices having similar magnitudes and spatial distributions of plasma and excited state densities can be obtained to dimensions of <15 μm by keeping pd and current density constant, and having a cathode fall thickness small compared to the characteristic dimension.
Colliding Singularities in F-theory and Phase Transitions

Abstract We study F-theory on elliptic Calabi-Yau three-folds near colliding singularities. We demonstrate that resolutions of those singularities generically correspond to transitions to phases characterized by new tensor multiplets and enhanced gauge symmetry. These are governed by the dynamics of tensionless strings. We also find new transition points which are associated with several small instantons simultaneously shrinking to zero size.
The changing time-series properties of earnings, cash flows and accruals: Has financial reporting become more conservative?

Abstract This paper documents changes in the patterns of earnings, cash flows and accruals over the last four decades. In the absence of a generally accepted definition of conservatism, a number of measures of reporting conservatism are identified and examined. These measures rely on the accumulation of nonoperating accruals, the timeliness of earnings with respect to bad and good news, characteristics of the earnings distribution and the market-to-book ratio. The patterns are consistent with an increase in conservative financial reporting over time. The findings have implications for accounting standard setting, regulation of financial information and financial statement analysis.
Heat Transfer Between Colliding Surfaces and Particles

Collisional heat transfer between two contacting curved surfaces is investigated computationally using a finite difference method and analytically using various asymptotic methods. Transformed coordinates that scale with the contact radius and the diffusion length are used for the computations. Hertzian contact theory of elasticity is used to characterize the contact area as a function of time. For an axisymmetric contact area, a two-dimensional self-similar solution for the thermal field during the initial period of contact is obtained, and it serves as an initial condition for the heat transfer simulation throughout the entire duration of collision. A two-dimensional asymptotic heat transfer result is obtained for small Fourier number. For finite Fourier numbers, local analytical solutions are presented to elucidate the nature of the singularity of the thermal field and heat flux near the contact point. From the computationally determined heat transfer during the collision, a closed-form formula is developed to predict the heat transfer as a function of the Fourier number, the thermal diffusivity ratio, and the thermal conductivity ratio of the impacting particles.
Decision-making authority and substance abuse treatment for adolescents: a survey of state laws.

Abstract Purpose State laws concerning decision-making authority for voluntary inpatient substance abuse (SA) treatment of minors may be a potential barrier to appropriate treatment. We sought to identify and classify relevant laws related to the provision of voluntary inpatient SA treatment to adolescents 12 to 17 years (minors) as an exploratory assessment to improve understanding of how these laws might affect treatment decisions. Methods In summer 2006, we conducted a survey of statutes, regulations, and legal cases in the 50 states and the District of Columbia regarding the authority of parents (or guardians) and minors to make treatment decisions for voluntary inpatient SA treatment. Results All 50 states have laws applicable to voluntary inpatient SA treatment for adolescents, and the laws vary significantly throughout the nation. If a minor and parent disagree about SA treatment, some states defer to the decision-making authority of the minor, whereas other states defer to the parent. Most significantly, the majority of states fail to specify whether the minor's or the parent's decision will control in the event of a conflict. Conclusions The lack of clarity in state laws regarding decision-making authority for voluntary inpatient SA treatment of minors may create a potential barrier to treatment for adolescents, especially those with more serious SA problems. This lack of clarity could lead to confusion among parents, adolescents, healthcare professionals, and treatment facilities, and ultimately could result in a failure to treat adolescents in need of medical attention. Policymakers should ensure that state laws clearly specify procedures to enable treatment if a conflict arises between adolescents and parents, including procedures to ensure that the due process rights of adolescents are protected.
Enantioselective Rhodium-Catalyzed [4+2+2] Cycloaddition of Dienyl Isocyanates for the Synthesis of Bicyclic Azocine Rings

A highly enantioselective rhodium-catalyzed [4+2+2] cycloaddition of terminal alkynes and dienyl isocyanates has been developed. The cycloaddition provides a rapid entry to highly functionalized and enantioenriched bicyclic azocines. This reaction represents the first [4+2+2] cycloaddition strategy to construct nitrogen-containing eight-membered rings.
How Chicagoan are Gary Becker's economic models of marriage?

This paper describes Gary Becker’s theoretical models of marriage. At the micro level, these are all rational choice models. At the market level, Becker offers two major types of models: partial equilibrium models based on price theory as taught by Marshall and Friedman; and optimal sorting models based on optimal assignment models. This paper examines some of the possible intellectual influences on Becker’s theory of marriage, compares Becker’s research on marriage with that of some scholars interested in intra-marriage distribution, and documents that Becker’s students at Chicago were more interested in Becker’s Friedmanian models of marriage than in his optimal assignment models.
X-Ray Properties of the NGC 1961 Group of Galaxies

We present an analysis of the ROSAT observations of the massive spiral galaxy NGC 1961 and surrounding small group of spiral galaxies. Contrary to the earlier Einstein observation which suggested that the X-ray emission comes mainly from an arc-shaped region on one side of NGC 1961, the ROSAT observations show that the X-ray emission is fairly typical for a spiral galaxy and comes mainly from the starburst nucleus with some contribution from the surrounding spiral arm regions. The total X-ray flux of 5.1 × 1040 ergs s-1 is normal, but the spectrum has an unusually narrow peak at 0.9 keV that can only be fit by models that have high absorption and low characteristic temperatures. A nearby bright X-ray source (LX = 1.7 × 1040 ergs s-1) at a projected distance of 44 kpc from NGC 1961 has no optical or radio counterpart and may be an example of the rare high-luminosity X-ray sources seen in a few other galaxies. There is no detectable diffuse X-ray emission in this group of spiral galaxies, but this is not unexpected because recent statistical studies show that groups with a hot intragroup medium (IGM) tend to have a higher velocity dispersion and contain a large fraction of elliptical and S0 galaxies. If there is a substantial IGM in this group, as is suggested by the head-tail distribution of H I gas around NGC 1961, then it must be cooler than ≈ 0.3 keV and thus invisible to the ROSAT detectors.
Vortex particles and tree codes: I. flows with arbitrary crossing between solid boundaries and particle redistribution lattice; II. vortex ring encountering a plane at an angle.

The first part of the paper deals with 2-D vortex methods. We briefly review the numerical method and we extensively describe two points in more details: the redistribution around an arbitrary body and a new scheme to diffuse a vortex sheet onto particles in a way that is most accurate. These two improvements allow to perform DNS of 2-D flows past bodies of arbitrary shape. We test and validate them on the flow past an impulsively started circular cylinder. The second part of the paper is about 3-D flows with solid boundaries. We test the viscous method on the interaction between a vortex ring and a plane. We also detail a modified version of the Particle Strength Exchange (PSE) scheme close to the solid boundary so as to enhance the accuracy of the method. Fast vortex codes are used for both 2-D and 3-D computations. The 3-D code is also parallel.
Fast computation of database operations using graphics processors

We present new algorithms for performing fast computation of several common database operations on commodity graphics processors. Specifically, we consider operations such as conjunctive selections, aggregations, and semi-linear queries, which are essential computational components of typical database, data warehousing, and data mining applications. While graphics processing units (GPUs) have been designed for fast display of geometric primitives, we utilize the inherent pipelining and parallelism, single instruction and multiple data (SIMD) capabilities, and vector processing functionality of GPUs, for evaluating boolean predicate combinations and semi-linear queries on attributes and executing database operations efficiently. Our algorithms take into account some of the limitations of the programming model of current GPUs and perform no data rearrangements. Our algorithms have been implemented on a programmable GPU (e.g. NVIDIA's GeForce FX 5900) and applied to databases consisting of up to a million records. We have compared their performance with an optimized implementation of CPU-based algorithms. Our experiments indicate that the graphics processor available on commodity computer systems is an effective co-processor for performing database operations.
Measuring the diffuse optical light in Abell 1651

Using drift-scan data, a new approach to determining surface brightness profiles, and techniques for detecting low surface brightness signals, we fit the light profile of the brightest cluster galaxy (BCG) in the rich cluster Abell 1651 out to 670 h-1 kpc. This radius is a significant fraction of the virial radius of the cluster (2 h-1 Mpc), indicating that the sizes of the BCG and the cluster are comparable. We find that the profile is consistent with a de Vaucouleurs profile over the radial range probed. We also find that the integrated light profile of the BCG in Abell 1651 contributes 36% of the total cluster light within 500 h-1 kpc. Including all luminous components, we obtain M/LI ~ 160 h for the cluster, which would be overestimated by ~20% without the BCG halo. Furthermore, the relatively red color of the BCG at large radii suggests that recent disruption and tidal stripping of spirals and dwarf ellipticals do not contribute significantly to the halo luminosity. The color and the form of the profile are consistent with a scenario in which the BCG forms from filamentary collapse during the epoch of cluster formation, with relatively little evolution in the past 5 Gyr. We remove the BCG and other detected galaxies from the image and construct a two-dimensional surface brightness map of the cluster core. Several knots of excess emission are found, but the total diffuse component is constrained to contribute less than 5% of the cluster light.
Coded DS-CDMA systems with iterative channel estimation and no pilot symbols

In this paper, we describe direct-sequence code-division multiple-access (DS-CDMA) systems with quadriphase-shift keying in which channel estimation, coherent demodulation, and decoding are iteratively performed without the use of any training or pilot symbols. An expectation-maximization channel-estimation algorithm for the fading amplitude, phase, and the interference power spectral density (PSD) due to the combined interference and thermal noise is proposed for DS-CDMA systems with irregular repeat-accumulate codes. After initial estimates of the fading amplitude, phase, and interference PSD are obtained from the received symbols, subsequent values of these parameters are iteratively updated by using the soft feedback from the channel decoder. The updated estimates are combined with the received symbols and iteratively passed to the decoder. The elimination of pilot symbols simplifies the system design and allows either an enhanced information throughput, an improved bit error rate, or greater spectral efficiency. The interference-PSD estimation enables DS-CDMA systems to significantly suppress interference.
A Note on John Kain's “Housing Segregation, Negro Employment and Metropolitan Decentralization”

I. Theory, 147.—II. Empirical results, 149.—III. Summary and conclusions, 155.—Appendix: Economic rationalisation for the nonlinear reduced form, 158.
Parametric Problems on Graphs of Bounded Tree-Width

We consider optimization problems on weighted graphs where vertex and edge weights are polynomial functions of a parameter ?. We show that, if a problem satisfies certain regularity properties and the underlying graph was bounded tree-width, the number of changes in the optimum solution is polynomially bounded. We also show that the description of the sequence of optimum solutions can be constructed in polynomial time and that certain parametric search problems can be solved in O(n log n) time, where n is the number of vertices in the graph.
Evidence-based medicine and complementary medicine

To apply evidence-based medicine (EBM) to complementary medicine (CM)—treatments such as acupuncture, chiropractic, homeopathy, or herbal medicine—seems, at first glance, a contradiction in terms. CM is often defined as techniques for which no evidence of benefit exists (or as a speaker at a recent Cochrane Colloquium put it, “medicine is either scientific or complementary”). But many of the interventions used by conventional clinicians have little scientific support; conversely, there is evidence from randomised trials in support of some interventions that are commonly described as CM. CM is an increasingly prevalent aspect of health care: about 10% of the UK population visit a practitioner each year,1 and about 40% of UK general practices offer their patients access to CM services on the national health service.2 As such, CM constitutes important area for the implementation of EBM for better patient care. There are two perspectives for thinking about EBM and CM. The external perspective is that of those outside CM. This might include a community mental health team deciding whether to employ an acupuncturist to treat addiction, a family physician considering whether to refer patients with anxiety disorders to a homeopath, or a patient deciding whether to buy an over the counter herbal remedy for depression. EBM can and should be used as part of such decisions. The internal perspective is that of CM practitioners themselves, finding, appraising, and acting on evidence to diagnose, treat, and prognose more effectively. This use of EBM is more problematic. Contrary to widespread belief, there is considerable …
‘Ethnic practices’ in translation: Tea in Japan and the US

Abstract In this article I examine the specific dynamics shaping and forming migrant “ethnic practices”. A comparison of tea ceremony in Japan and the US provides a particularly interesting site since its philosophy promotes universalism and adaptation to the surrounding environment in Japan and the US. I first briefly examine how tea is seen as quintessentially Japanese in Japan through cultural objectification, a process that disassociates it from everyday experiences and enables practitioners to re-internalize what is deemed quintessentially Japanese – yet distant and difficult. Then I explore how implications of tea as a Japanese practice shift when recreated in the US. In contrast to the situation in Japan, the practice is naturalized for Japanese in the US. But alongside such naturalization also emerges a suspicion of authenticity, particularly regarding how this “Japanese” practice is accomplished abroad. Consequently, practitioners attempt to recreate Japan as they recreate tea rather than followi...
The Exceptional Conformational Bias of 1,5-Diene-3,4-diols Is Controlled by Electrostatic Interactions: A Theoretical Elucidation of the Origin in Rotational Isomer Stability.

A conformational study of 1,5-hexadiene-3,4-diol (1) and 3-buten-1-ol (2) with the ab initio molecular orbital methods reveals that electrostatic interactions, rather than steric or tosional effects, control the conformational preferences of these compounds. It is found that the 1,2-dioxygen function prefers the anti arrangement due to the lone pair electron repulsion. A pseudo 1,3-diaxial oxygen/π bond repulsion and a 1,3-diaxial attraction between an oxygen lone pair and a vinyl H are found to be responsible for the profound preference for the CO-eclipsed form in diol 1. Quantitatively, the repulsion between two gauche oxygen atoms is calculated to be ∼1.5 kcal/mol at the MP2/6-31G**//HF/6-31G* level of theory. The repulsion between an oxygen atom and a π bond at the pseudo 1,3-diaxial position is ∼1 kcal/mol, and the attractive interaction between an oxygen atom and a vinyl H at the pseudo 1,3-diaxial position is ∼0.5 kcal/mol, respectively, at the MP2/6-31G*//MP2/6-31G* level.
Transformation of Fused Bicyclic and Tricyclic β-Lactones to Fused γ-Lactones and 3(2H)-Furanones via Ring Expansions and O−H Insertions

A two-step strategy for conversion of β-lactones to γ-lactones and 3(2H)-furanones was developed involving initial acyl C−O cleavage leading to δ-hydroxy-α-diazo-β-ketoesters and β-ketophosphonates. Subsequent tandem Wolff rearrangement/lactonization of these α-diazo intermediates provided cis-fused γ-lactones efficiently under photolytic or thermolytic conditions. In addition, cis-fused 3(2H)-furanones were obtained by rhodium(II)-catalyzed O−H insertion reactions of the δ-hydroxy-α-diazo intermediates.
THE FORMATION MECHANISM OF GAS GIANTS ON WIDE ORBITS

The recent discoveries of massive planets on ultra-wide orbits of HR 8799 and Fomalhaut present a new challenge for planet formation theorists. Our goal is to figure out which of three giant planet formation mechanisms— core accretion (with or without migration), scattering from the inner disk, or gravitational instability—could be responsible for Fomalhaut b, HR 8799 b, c and d, and similar planets discovered in the future. This paper presents the results of numerical experiments comparing the long-period planet formation efficiency of each possible mechanism in model A star, G star, and M star disks. First, a simple core accretion simulation shows that planet cores forming beyond 35 AU cannot reach critical mass, even under the most favorable conditions one can construct. Second, a set of N-body simulations demonstrates that planet–planet scattering does not create stable, wide-orbit systems such as HR 8799. Finally, a linear stability analysis verifies previous work showing that global spiral instabilities naturally arise in high-mass disks. We conclude that massive gas giants on stable orbits with semimajor axes a ≳35 AU form by gravitational instability in the disk. We recommend that observers examine the planet detection rate as a function of stellar age, controlling for the planets’ dimming with time. Any age trend would indicate that planets on wide orbits are transient relics of scattering from the inner disk. If planet detection rate is found to be independent of stellar age, it would confirm our prediction that gravitational instability is the dominant mode of producing detectable planets on wide orbits.We also predict that the occurrence ratio of long-period to short-period gas giants should be highest for M dwarfs due to the inefficiency of core accretion and the expected small fragment mass (~10 M_(Jup)) in their disks.
Disorder and the quantum Hall ferromagnet

The distinguishing feature of the quantum Hall ferromagnet is the identity between electrical and topological charge densities of a spin distortion. In addition to the wealth of physics associated with Skyrmionic excitations of the quantum Hall ferromagnet, this identification permits a rather curious coupling of spin waves to the disorder potential. A wave packet of spin waves has an associated, oscillating dipole charge distribution, due to the nonlinear form of the topological density. We investigate the way in which this coupling modifies the conductivity and temperature dependence of magnetization of the quantum Hall ferromagnet. [S0163-1829(98)51016-8].
GENETIC HETEROGENEITY IN FUCOSIDOSIS

Fucosidosis is an autosomal recessive lysosomal disorder resulting from the deficient activity of the enzyme alpha-L-fucosidase. The originally described cases were characterized clinically by progressive psychomotor retardation, severe neurologic signs, coarsening of facial features, variable skeletal abnormalities, and fatal outcome in childhood. Three cases of fucosidosis with a different clinical picture have been described. We are reporting two brothers, 4½ and 9 years old, affected by a variant form of fucosidosis indicating genetic heterogeneity of this storage disease. A marked deficiency of alpha-L-fucosidase was demonstrated in cultured skin fibroblasts of both patients (0.0 to 3.5 n moles of p-nitrocatechol/mg protein/hour). The enzymatic activity in the parents (32.0) was approximately 28% of the activity of control fibroblasts (111.2). This new form of fucosidosis (fucosidosis type 2) is characterized by angiokeratoma corporis diffusum, spondyloepiphyseal dysplasia, as well as a milder course of psychomotor retardation, milder neurologic findings, and a longer survival than the originally described cases of the disease. Because of similarities of type 2 fucosidosis with mucopolysaccharidosis and Fabry's disease, the differential diagnosis of these disorders should include alpha-L-fucosidase determination.
Relaxation of a rubbed polystyrene surface.

The relaxation dynamics of a rubbed polystyrene (PS) surface have been characterized using infrared-visible sum frequency generation spectroscopy (SFG). The SFG results were compared with previous relaxation of retardation measurements, and the results show that the rubbed PS surface has the same ${T}_{g}$ as the bulk where ${T}_{g}$ is defined as $\ensuremath{\tau}{(T}_{g})=5\mathrm{s},$ however, the surface has a lower activation energy $(\ensuremath{\Delta}E)$ and a larger stretching exponent $({\ensuremath{\beta}}_{\mathrm{KWW}})$ than bulk PS. This indicates that the surface region relaxes more quickly than the bulk. The thickness of this region of lower $\ensuremath{\Delta}E$ and larger ${\ensuremath{\beta}}_{\mathrm{KWW}}$ is estimated to be roughly 12 nm.
Who discovered Mount Everest

The discovery that Mount Everest is the highest mountain in the world was made by the officers of the Survey of India. This organization measured a network of triangulation across India between 1800 and 1870. In order to reduce the measurements to geodetic coordinates, it was necessary to determine the size and shape of the earth. This was accomplished by measuring the length of an arc of the meridian under the direction of the Surveyor General, Sir George Everest. This measurement disagreed with the observations of the stars for latitude by 5 seconds of arc (530 ft or 162 m). In 1855, Pratt and Airy pointed out that the discrepancy was due to the gravitational effect of the Himalayas. Their work was the first indication that the material of the earth's crust under the mountains is lighter than that under plains. During the course of the survey the officers made observations on the snowy Himalayas. They were excluded from Nepal; observations had to be taken from more than 100 mi (160 km) away in jungles infested by malaria. Mount Everest was observed by three different officers between November 27, 1847, and January 17, 1850. The height of the mountain had to be determined by the (human) computers in the survey headquarters in Dehra Dun. The fact that it is the highest mountain in the Himalayas, and probably in the world, was announced by Surveyor General Andrew Waugh in 1856. It is not clear whether the chief computer who made the calculations was an Indian, Radanath Sikhdar, or an Englishman born in India of an Indian mother, John B. N. Hennesy. The local name for the mountain, if it had any, was unknown, so Waugh named it Mount Everest, in honor of the great scientist who was largely responsible for the accomplishments of the Survey of India.
Geometric multigrid for an implicit-time immersed boundary method

The immersed boundary (IB) method is an approach to fluid-structure interaction that uses Lagrangian variables to describe the deformations and resulting forces of the structure and Eulerian variables to describe the motion and forces of the fluid. Explicit time stepping schemes for the IB method require solvers only for Eulerian equations, for which fast Cartesian grid solution methods are available. Such methods are relatively straightforward to develop and are widely used in practice but often require very small time steps to maintain stability. Implicit-time IB methods permit the stable use of large time steps, but efficient implementations of such methods require significantly more complex solvers that effectively treat both Lagrangian and Eulerian variables simultaneously. Several different approaches to solving the coupled Lagrangian-Eulerian equations have been proposed, but a complete understanding of this problem is still emerging. This paper presents a geometric multigrid method for an implicit-time discretization of the IB equations. This multigrid scheme uses a generalization of box relaxation that is shown to handle problems in which the physical stiffness of the structure is very large. Numerical examples are provided to illustrate the effectiveness and efficiency of the algorithms described herein. These tests show that using multigrid as a preconditioner for a Krylov method yields improvements in both robustness and efficiency as compared to using multigrid as a solver. They also demonstrate that with a time step 100---1000 times larger than that permitted by an explicit IB method, the multigrid-preconditioned implicit IB method is approximately 50---200 times more efficient than the explicit method.
Optimization techniques for permittivity and permeability determination

This paper discusses optimization techniques for the determination of complex permittivity and permeability in transmission lines. The traditional theoretical model using scattering parameters is extended into a mathematical regression model that can be solved with widely accepted numerical techniques. This new model produces accurate primary mode results for the samples tested including nonmagnetic and magnetic materials with high dielectric constants. An extension of the model includes responses due to higher order modes. The general model determines parameters to specify the spectral functional form of complex permittivity and permeability and is capable of small corrections to independent variable data including angular frequency, sample length, sample position, and cutoff wavelength. The method provides reliable determination for both low and high permittivity materials.
Catalytic cyclophanes: A highly efficient model for pyruvate oxidase

Abstract The thiazolium macrocycle 1 is prepared by a novel synthetic route to monofunctionalized cyclophanes. Host 1 is a very efficient catalyst for the oxidation of aromatic aldehydes to carboxylic acids in the presence of potassium ferricyanide.
Interaction strictly improves the Wyner-Ziv rate-distortion function

In 1985 Kaspi provided a single-letter characterization of the sum-rate-distortion function for a two-way lossy source coding problem in which two terminals send multiple messages back and forth with the goal of reproducing each other's sources. Yet, the question remained whether more messages can strictly improve the sum-rate-distortion function. Viewing the sum-rate as a functional of the distortions and the joint source distribution and leveraging its convex-geometric properties, we construct an example which shows that two messages can strictly improve the one-message (Wyner-Ziv) rate-distortion function. The example also shows that the ratio of the one-message rate to the two-message sum-rate can be arbitrarily large and simultaneously the ratio of the backward rate to the forward rate in the two-message sum-rate can be arbitrarily small.
Effects of Display Gain on Human Operator Information Processing Rate in a Rate Control Tracking Task

A single-axis rate control tracking experiment was conducted to determine the sensitivity of transinformation (information processing rate in bits/s) to display gain, display type (pursuit or compensatory), and forcing function bandwidth. Four other performance measures were also derived: relative error, relative noiseless error, relative remnant, and system open-loop crossover frequency. It was shown that human information processing rates increased to a maximum and then decreased as a function of both display gain and forcing function bandwidth. In general, little difference in transinformation performance was noted between pursuit and compensatory displays.
Space Event Detection Method

A method was developed to detect space events, such as maneuvers, collisions, explosions, etc., involving space objects tracked by the CheyenneMountain Operations Center. The CheyenneMountain Operations Center creates state vector parameters for tracked objects and places them in a catalog with the corresponding time. This time dependent data can be processed to reveal sudden unexpected changes in parameter values referred to as space events. A moving window curve fit technique was found effective in estimating a parameter’s value and detecting sudden changes indicative of space events. Themovingwindow technique filters noise and permits processing of time varying data. When a parameter’s deviation from its expected value exceeds a predefined threshold, an event is declared. The processing method was implemented and tested on space object data. Space vehicle maneuvers, collisions and space weather events were readily detected. Themethod does not involve state vector propagation and is very computationally efficient.
Conformal invariance for non-relativistic field theory

Abstract Momentum space Ward identities are derived for the amputated n-point Green's functions in 3+1 dimensional non-relativistic conformal field theory. For n=4 and 6 the implications for scattering amplitudes (i.e. on-shell amputated Green's functions) are considered. Any scale invariant 2-to-2 scattering amplitude is also conformally invariant. However, conformal invariance imposes constraints on off-shell Green's functions and the three particle scattering amplitude which are not automatically satisfied if they are scale invariant. As an explicit example of a conformally invariant theory we consider non-relativistic particles in the infinite scattering length limit.
Impact of tooth friction and its bending effect on gear dynamics

Abstract This work studies the influences of tooth friction on parametric instabilities and dynamic response of a single-mesh gear pair. A mechanism whereby tooth friction causes gear tooth bending is shown to significantly impact the dynamic response. A dynamic translational–rotational model is developed to consider this mechanism together with the other contributions of tooth friction and mesh stiffness fluctuation. An iterative integration method to analyze parametric instabilities is proposed and compared with an established numerical method. Perturbation analysis is conducted to find approximate solutions that predict and explain the numerical parametric instabilities. The effects of time-varying friction moments about the gear centers and friction-induced tooth bending are critical to parametric instabilities and dynamic response. The impacts of friction coefficient, bending effect, contact ratio, and modal damping on the stability boundaries are revealed. Finally, the friction bending effect on the nonlinear dynamic response is examined and validated by finite element results.
Spectroscopic constants and potential energy curves of GaAs, GaAs+, and GaAs−

Abstract Twenty electronic states of GaAs, 12 electronic states of GaAs + , and 13 electronic states of GaAs − are investigated using relativistic ab initio complete active space MCSCF (CASSCF) followed by large-scale configuration interaction calculations which included up to 700 000 configurations. Potential energy curves and spectroscopic constants of all these states of three radicals are obtained. Spectroscopic constants of low-lying states of GaAs are in very good agreement with both experiment and all-electron results. Two nearly-degenerate states of 2 Σ + , 2 Π ( 2 Σ + lower) symmetries are found as candidates for the ground state of GaAs − . The GaAs − negative ion is found to be more stable compared to the neutral GaAs ( D e (GaAs − ) = 3 eV). The electron affinity of GaAs is computed as 0.89 and 1.3 eV at the FOCI and SOCI levels of theory, respectively. Calculated potential energy curves of GaAs are in accord with the experimentally observed predissociation in the 3 Π( III ) - X 3 Σ − system.
An optimal DNA segmentation based on the MDL principle

The biological world is highly stochastic and inhomogeneous in its behaviour. There are regions in DNA with a high concentration of G or C bases; stretches of sequences with an abundance of CG dinucleotide (CpG islands); coding regions with strong periodicity-of-three pattern, and so forth. Transitions between these regions of DNA, known also as change points, carry important biological information. Computational methods used to identify these homogeneous regions are called segmentations. Viewing a DNA sequence as a non-stationary process, we apply recent novel techniques of universal source coding to discover stationary (possibly recurrent) segments. In particular, the Stein-Ziv lemma is adopted to find an asymptotically optimal discriminant function that determines whether two DNA segments are generated by the same source assuring exponentially small false positives. Next, we use the Minimum Description Length (MDL) principle to select parameters that lead to a linear-time segmentation algorithm. We apply our algorithm to human chromosome 9 and chromosome 20 to discover coding and noncoding regions, starting positions of genes, as well as the beginning of CpG islands.
Cyber-security research ethics dialogue & strategy workshop

The inaugural Cyber-security Research Ethics Dialogue & Strategy Workshop was held on May 23, 2013, in conjunction with the IEEE Security Privacy Symposium in San Francisco, California. CREDS embraced the theme of "ethics-by-design" in the context of cyber security research, and aimed to: Educate participants about underlying ethics principles and applications;Discuss ethical frameworks and how they are applied across the various stakeholders and respective communities who are involved;Impart recommendations about how ethical frameworks can be used to inform policymakers in evaluating the ethical underpinning of critical policy decisions;Explore cyber security research ethics techniques,tools,standards and practices so researchers can apply ethical principles within their research methodologies; andDiscuss specific case vignettes and explore the ethical implications of common research acts and omissions.
The Index of Operators on Foliated Bundles

Abstract We compute the equivariant cohomology Connes–Karoubi character of the index of elliptic operators along the leaves of the foliation of a flat bundle. The proof uses techniques similar to those developed in Algebraic Topology, in the study of non-commutative algebras.