cssi/SciSciGPT-SciSciNet huggingface dataset:
Reading the correct history?: modeling temporal intention in resource sharing

The web is trapped in the "perpetual now", and when users traverse from page to page, they are seeing the state of the web resource (i.e., the page) as it exists at the time of the click and not necessarily at the time when the link was made. Thus, a temporal discrepancy can arise between the resource at the time the page author created a link to it and the time when a reader follows the link. This is especially important in the context of social media: the ease of sharing links in a tweet or Facebook post allows many people to author web content, but the space constraints combined with poor awareness by authors often prevents sufficient context from being generated to determine the intent of the post. If the links are clicked as soon as they are shared, the temporal distance between sharing and clicking is so small that there is little to no difference in content. However, not all clicks occur immediately, and a delay of days or even hours can result in reading something other than what the author intended. We introduce the concept of a user's temporal intention upon publishing a link in social media. We investigate the features that could be extracted from the post, the linked resource, and the patterns of social dissemination to model this user intention. Finally, we analyze the historical integrity of the shared resources in social media across time. In other words, how much is the knowledge of the author's intent beneficial in maintaining the consistency of the story being told through social posts and in enriching the archived content coverage and depth of vulnerable resources?
Casimirs of the Goldman Lie algebra of a closed surface

In 1986 Goldman introduced a Lie algebra structure on the linear span L of conjugacy classes of the fundamental group of a closed oriented surface. It is easy to see that the class e_1 of the trivial loop is a central element in L. We prove that any central element of L is a multiple of e_1 (a conjecture communicated to the author by Chas and Sullivan), and moreover that any central element of the Poisson algebra SL is a polynomial of e_1.
Modelling of an Elastic Disk With Finite Hub Motions and Small Elastic Vibrations With Application to Rotordynamics

In the modelling of flexible structures undergoing large overall motion and small elastic vibrations, it is necessary to include elastic displacement effects up to second order in the kinematical equations if the resulting differential equations are to be consistent. Elastic displacements are typically modelled using mode shapes and generalized coordinates, and second and higher order elastic effects (sometimes referred to as foreshortening) are often neglected in the development of kinematical relations. This study examines the implications of such effects in the modelling of an elastic disk with arbitrary base motions and small elastic vibrations. A general modelling procedure is described that is appropriate for the development of simulation models for such structures. An approximate technique is used to account for second order elastic terms in the kinematical relations. The modelling procedure is specialized to the case of an elastic disk undergoing a constant axial spin and infinitesimal displacements for all other degrees of freedom. Comparisons are made between the natural frequencies of a disk model with and without these elastic foreshortening effects and some conclusions are drawn as to the relative importance of such terms in rotor disk modelling.
When Retweets Attack Are Twitter Users Liable for Republishing the Defamatory Tweets of Others

Under the republication doctrine, repeating false and defamatory statements has traditionally triggered liability for the repeater. However, some confusion has emerged regarding retweeting posts of...
Heavy-quark correlations in deep-inelastic electroproduction

Abstract We have completed the next-to-leading order perturbative QCD corrections to the virtual-photon exclusive differential cross sections for heavy quark production in deep-inelastic electron-proton scattering, i.e. e + P a Q + Q + X . Using these results, we have computed distributions which are sensitive to correlations among the heavy quark, the heavy antiquark, and the associated jet. Some predictions for charm and bottom heavy quark production at the electron-proton collider HERA are presented.
Quantum Optical Technologies for Metrology, Sensing, and Imaging

Over the past 20 years, bright sources of entangled photons have led to a renaissance in quantum optical interferometry. Optical interferometry has been used to test the foundations of quantum mechanics and implement some of the novel ideas associated with quantum entanglement such as quantum teleportation, quantum cryptography, quantum lithography, quantum computing logic gates, and quantum metrology. In this paper, we focus on the new ways that have been developed to exploit quantum optical entanglement in quantum metrology to beat the shot-noise limit, which can be used, e.g., in fiber optical gyroscopes and in sensors for biological or chemical targets. We also discuss how this entanglement can be used to beat the Rayleigh diffraction limit in imaging systems such as in LIDAR and optical lithography.
Recent Advances in Studies of the Nova Outburst

It is a pleasure for me to present a review of the nova outburst at the Spring 1991 meeting of the Astronomische Gessellschaft and I am very grateful to the organizers for inviting me to give this talk. I will present a brief introduction and then mention three problems that have undergone much work in Germany. These problems are (1) the abundances of the elements in nova ejecta, (2) X-ray emission during the outburst (which will also give me a chance to mention the 1991 outburst of Nova Her and its detection by ROSAT), and (3) a new stellar atmosphere study of the early IUE spectra of novae. Novae in outburst have been the object of intense study for more than 100 years but it is only in the last three decades that we have made significant progress in understanding both the cause of their outbursts and the extraordinary phenomena that they display during their outbursts. These fascinating objects exhibit such a diversity of behavior, both in outburst and in quiescence, that virtually all of the techniques and analyses of modern astronomy have been used to understand their behavior.
Optical Properties of Quantum-Dot-Doped Liquid Scintillators

Semiconductor nanoparticles (quantum dots) were studied in the context of liquid scintillator development for upcoming neutrino experiments. The unique optical and chemical properties of quantum dots are particularly promising for the use in neutrinoless double-beta decay experiments. Liquid scintillators for large scale neutrino detectors have to meet specific requirements which are reviewed, highlighting the peculiarities of quantum-dot-doping. In this paper, we report results on laboratory-scale measurements of the attenuation length and the fluorescence properties of three commercial quantum dot samples. The results include absorbance and emission stability measurements, improvement in transparency due to filtering of the quantum dot samples, precipitation tests to isolate the quantum dots from solution and energy transfer studies with quantum dots and the fluorophore PPO.
BRIDGE MANAGEMENT FOR THE 21ST CENTURY

Bridge management has been a subject of intense interest and development for the past 10 years. In support of improved bridge management, FHWA funded the development of the Pontis bridge computer program, which is now in use by approximately 40 of the 50 states. In addition, many new guide specifications have been produced to assist bridge managers in their efforts to better manage the nation's aging bridge inventory. The AASHTO Subcommittee on Bridges and Structures has taken the lead along with FHWA in implementing the improved bridge management systems. California and a few other states have been critical of the current ranking system for bridge maintenance and have been working to develop an improved performance measure. The bridge health index (HI), an improved and more comprehensive numerical rating system that uses the element inspection data to determine the remaining asset value of a bridge or network of bridges, is discussed. The HI is more consistent with the element-level evaluation data colle...
2-Benzoyloxynitroethylene as a cis-2-aminoethenol equivalent

Abstract Nitroester 1 reacts readily with dienes to afford trans-nitroesters which are reduced to cis-aminoalcohols.
The Detectability of Neon Fluorescence and Measurement of the Solar Photospheric Neon Abundance

Monte Carlo calculations of the Ne Kα line fluoresced by coronal X-rays and emitted near the temperature minimum region of the solar atmosphere have been employed to investigate the use of this feature to measure directly the solar photospheric Ne abundance. Although very weak, comparison with spectral line databases indicates that at plasma temperatures typical of the quiet Sun and cool active regions (≤2 × 106 K) the line is isolated and unblended. A canonical solar chemical composition yields an equivalent width of ~6 mA (0.3 eV) when observed at heliocentric angles ~0. For a 1' field of view, photon fluxes at Earth are of order 0.2 photons s-1 for the quiet Sun, rendering the Ne Kα fluorescent line a quite feasible means for determining the solar photospheric Ne content.
Application-Aware NoC Design for Efficient SDRAM Access

In systems-on-chip (SoCs), a microprocessor demands guaranteed synchronous dynamic random access memory (SDRAM) latency whereas most of the other cores are served as a best-effort packet. However, a priority service for the guaranteed latency causes the SDRAM utilization and latency of an overall system to be degraded critically. In addition, the data size of SDRAM requested by various cores is not matched with an SDRAM access granularity such that the SDRAM utilization and latency are further deteriorated. In this paper, we propose an application-aware networks-on-chip (NoCs) design for an efficient SDRAM access, which can consider memory latency demands and memory access granularities in various applications. In order to provide short latency for priority memory requests with few penalties, memory request packets are scheduled by our guaranteed SDRAM service router that includes a hybrid flow controller of priority-first and priority-equal algorithms. In addition, our SDRAM access granularity matching NoC design further improves the memory performance by splitting a memory request packet to several short memory request packets and then controlling the short memory request packets with a partially open-page mode and an auto-precharge operation in a memory subsystem. Experimental results show that our cost-effective application-aware NoC design significantly improves, on average, memory latency for latency-sensitive cores up to 32.8%, overall memory latency up to 7.8%, and memory utilization up to 3.4%, compared to the state-of-the-art SDRAM-aware NoC design .
Safety and efficacy of intravenous quinidine

Abstract The safety and efficacy of intravenous quinidine were evaluated in a patient population with a high prevalence of left ventricular dysfunction and intraventricular conduction delays. Quinidine gluconate (mean dose 9.1 ± 1.6 mg/kg) was administered during electrophysiologic study to 100 patients with ventricular or supraventricular tachyarrhythmias. Clinical heart failure was present in 68 percent of the patients. Left ventricular end-diastolic pressure, cardiac index, and left ventricular ejection fraction were abnormal in 62, 48, and 70 percent, respectively. Major intraventricular conduction delays (QRS of 120 msec or more) were present in 27 percent, and the H-V interval was prolonged (over 55 msec) in 28 percent. Despite the prevalence of these abnormalities, quinidine was discontinued because of hypotension in only 10 patients. Saline solution was infused to maintain preload in 37 percent, and hypotension responded promptly to saline solution infusion or discontinuation of quinidine infusion in all subjects. Hypotension was not more common in patients with more severe left ventricular dysfunction. QRS duration, H–V interval, QTc, and right ventricular effective refractory period increased significantly (p
Reduction of Sterically Hindered α,α-disubstituted Amino Esters

Abstract Reductions of a series of highly hindered α,α-disubstituted amino esters to the corresponding amino alcohols were accomplished using the BuLi-DIBAl “ate complex”. In addition, the novel amino acid a-benzyl histidine was reduced via α persilylation/LAH reduction protocol.
Localization of Carbonic Anhydrase in the Plumula of the Tooth of Lytechinus variegatus (Echinodermata: Echinoidea)

Labeled inhibitor autoradiography showed that carbonic anhydrase (CA) occurs in (1) the epithelium, (2) free odontoblasts and fibroblasts, (3) row odontoblasts and their membranes surrounding the calcareous parts and (4) extracellular areas. Extracellular CA occurs in areas where fibroblasts and collagen fibers are abundant. The localization of CA suggests that CA facilitates the movement of CO2 through the membrane and/or extracellular spaces to promote calcification.
Application generators at IBM

This paper discusses the reasons for the great interest in application generation. Because of the growing backlog of user demands on data processing, a new technology with an order-of-magnitude increase in productivity is suggested. IBM has two families of application generation products. One, DMS, operates in a CICS/VS environment; the other, IMSADF, operates in an IMS/VS environment. An overview of the techniques involved and the benefits of using these systems is discussed.
Evolution of forecast disagreement in a Bayesian learning model

We estimate a Bayesian learning model with heterogeneity aimed at explaining expert forecast disagreement and its evolution over horizons. Disagreement is postulated to have three components due to differences in: (i) the initial prior beliefs, (ii) the weights attached on priors, and (iii) interpreting public information. The fixed-target, multi-horizon, cross-country feature of the panel data allows us to estimate the relative importance of each component precisely. The first component explains nearly all to 30% of forecast disagreement as the horizon decreases from 24 months to 1 month. This finding firmly establishes the role of initial prior beliefs in generating expectation stickiness. We find the second component to have barely any effect on the evolution of forecast disagreement among experts. The importance of the third component increases from almost nothing to 70% as the horizon gets shorter via its interaction with the quality of the incoming news. We propose a new test of forecast efficiency in the context of Bayesian information processing and find significant heterogeneity in the nature of inefficiency across horizons and countries.
The 2‐Naphthylmethyl (NAP) Group in Carbohydrate Synthesis: First Total Synthesis of the GlyCAM‐1 Oligosaccharide Structures

Total syntheses of the GlyCAM-1 (glycosylation-dependent cell adhesion molecule-1) oligosaccharide structures: [alpha-NeuAc-(2 --> 3)-beta-Gal-(1 --> 4)-[alpha-Fuc-(1 --> 3)]-beta-(6-O-SO3Na)-GlcNAc-(1 --> 6)]-[alpha-NeuAc-(2 --> 3)-beta-Gal-(1 --> 3)]-alpha-GalNAc-OMe (1) and [alpha-NeuAc-(2 --> 3)-beta-Gal-(1 --> 4)-[alpha-Fuc-(1 --> 3)]-beta-GlcNAc-(1 --> 6)]-[alpha-NeuAc-(2 3)-beta-Gal-(1 --> 3)]-alpha-GalNAc-OMe (2) through a novel sialyl LewisX tetrasaccharide donor are described. Employing sequential glycosylation strategy, the starting trisaccharide was regio- and stereoselectively constructed through coupling of a disaccharide imidate with the monosaccharide acceptor phenyl-6-O-naphthylmethyl-2-deoxy-2-phthalimido-1-thio-beta-D-glucopyranoside with TMSOTf as a catalyst without affecting the SPh group. The novel sialyl Lewisx tetrasaccharide donor 3 was then obtained by alpha-L-fucosylation of trisaccharide acceptor with the 2,3,4-tri-O-benzyl-1-thio-beta-L-fucoside donor. The structure of the novel sialyl Lewisx tetrasaccharide was established by a combination of 2D DQF-COSY and 2D ROESY experiments. Target oligosaccharides 1 and 2 were eventually constructed through heptasaccharide which was obtained by regioselective assembly of advanced sialyl Lewisx tetrasaccharide donor 3 and a sialylated trisaccharide acceptor in a predictable and controlled manner. Finally, target heptasaccharides 1 and 2 were fully characterized by 2D DQF-COSY, 2D ROESY, HSQC, HMBC experiments and FAB mass spectroscopy.
Microwave-assisted synthesis of novel bis(2-thioxothiazolidin-4-one) derivatives as potential GSK-3 inhibitors

Abstract (5Z,5′Z)-3,3′-(1,4-Phenylenebis(methylene)-bis-(5-arylidene-2-thioxothiazolidin-4-one) derivatives ( 5a – r ) have been synthesized by the condensation reaction of 3,3′-(1,4- or 1,3-phenylenebis(methylene))bis(2-thioxothiazolidin-4-ones) ( 3a , b ) with suitably substituted aldehydes (4a–f) or 2-(1 H -indol-3-yl)2-oxoacetaldehydes ( 8a – c ) under microwave conditions. The bis(2-thioxothiazolidin-4-ones) were prepared from the corresponding primary alkyl amines ( 1a , b ) and di-(carboxymethyl)-trithiocarbonyl ( 2 ). The 2-(1 H -indol-3-yl)-2-oxoacetaldehydes ( 8a – c ) were synthesized from the corresponding acid chlorides ( 7a – c ) using HSnBu 3 .
Epidemiology of dry eye syndrome.

Dry eye syndrome (DES) represents a heterogeneous group of conditions that share inadequate lubrication of the ocular surface as their common denominator. DES is characterized by symptoms of ocular dryness and discomfort due to insufficient tear quantity or quality caused by low tear production and/or excessive tear evaporation. Symptoms can be debilitating 1 and, when severe, may affect psychological health and ability to work. No cure exists for DES, which is one of the leading causes of patient visits to ophthalmologists and optometrists in the United States. Because of the presumed high prevalence of DES and the attendant health care burden, the National Eye Institute (NEI) has identified tear film and dry eye research as important areas in need of further study.
Primitive elements in the matroid-minor Hopf algebra

We introduce the matroid-minor coalgebra C, which has labeled matroids as distinguished basis and coproduct given by splitting a matroid into a submatroid and complementary contraction in all possible ways. We introduce two new bases for C; the first of these is related to the distinguished basis by Mobius inversion over the rank-preserving weak order on matroids, the second by Mobius inversion over the suborder excluding matroids that are irreducible with respect to the free product operation. We show that the subset of each of these bases corresponding to the set of irreducible matroids is a basis for the subspace of primitive elements of C. Projecting C onto the matroid-minor Hopf algebra H, we obtain bases for the subspace of primitive elements of H.
On the Saddle-Point Solution and the Large-Coalition Asymptotics of Fingerprinting Games

We study a fingerprinting game in which the number of colluders and the collusion channel are unknown. The encoder embeds fingerprints into a host sequence and provides the decoder with the capability to trace back pirated copies to the colluders. Fingerprinting capacity has recently been derived as the limit value of a sequence of maximin games with mutual information as their payoff functions. However, these games generally do not admit saddle-point solutions and are very hard to solve numerically. Here under the so-called Boneh-Shaw marking assumption, we reformulate the capacity as the value of a single two-person zero-sum game, and show that it is achieved by a saddle-point solution. If the maximal coalition size is k and the fingerprinting alphabet is binary, we show that capacity decays quadratically with k. Furthermore, we prove rigorously that the asymptotic capacity is 1/(k221n2) and we confirm our earlier conjecture that Tardos' choice of the arcsine distribution asymptotically maximizes the mutual information payoff function while the interleaving attack minimizes it. Along with the asymptotics, numerical solutions to the game for small k are also presented.
Nonexistence of a shock layer in gas dynamics with a nonconvex equation of state

A classical result of Gilbarg states that a simple shock wave solution of Euler's equations is compressive if and only if a corresponding shock layer solution of the Navier-Stokes equations exists, assuming, among other things, that the equation of state is convex. An “entropy condition” appropriate for weeding out “unphysical” shocks in the nonconvex case has been introduced by T.-P. Liu. For shocks satisfying his entropy condition, Liu showed that purely viscous shock layers exist (with zero heat conduction). Dropping the convexity assumption, but retaining many other reasonable restrictions on the equation of state, we construct an example of a (large amplitude) shock which satisfies Liu's entropy condition but for which a shock layer does not exist if heat conduction dominates viscosity. We also give a simple restriction, weaker than convexity, which does guarantee that shocks which satisfy Liu's entropy condition always admit shock layers.
The Separate Spectra of Pluto and its Satellite Charon

The March 3, 1987 occultation of Charon by Pluto was observed spectroscopically from 5400 to 10,200 A at a resolution of 12 A. The midpoint of the event occurred at 11:06 UT; the depth of the event at 6800 A was 0.162 mag. The spectrum of Charon is completely featureless and almost perfectly flat; the red slope and the CH4 absorption features can be attributed solely to Pluto.
Meditaciones postmodernas sobre el castigo: acerca de los límites de la razón y de las virtudes de la aleatoriedad (una polémica y un manifiesto para el siglo XXI)

Durante la modernidad, el discurso sobre la pena ha girado circularmente en torno a tres grupos de interrogantes. El primero, surgido de la propia Ilustracion, preguntaba: ?En que basa el soberano su derecho de penar? Nietzsche con mayor determinacion, pero tambien otros, argumentaron que la propia pregunta implicaba ya su respuesta. Con el nacimiento de las ciencias sociales, este escepticismo hizo surgir un segundo conjunto de interrogantes: ?Cual es, entonces, la verdadera funcion de la pena? ?Que es lo que hacemos cuando penamos? Una serie de criticas ulteriores -de metanarrativas, funcionalistas o de objetividad cientifica- debilitaron esta segunda linea de indagacion, y contribuyeron a dar forma a un tercer conjunto de interrogantes: ?Que nos cuenta la pena de nosotros mismos y de nuestra cultura? ?Que esta sucediendo que nos permita ver lo que se halla tras el giro cultural? ?Que interrogantes podemos -nosotros, hijos del siglo XXI- formular en relacion con nuestras practicas e instituciones punitivas?Este ensayo argumenta que debemos abandonar el desorientado proyecto de la modernidad, reconocer de una vez y definitivamente los limites de la razon, y orientarnos hacia la aleatoriedad y el azar. En todos los textos modernos llego siempre un momentoen el que los hechos empiricos se agotaron y las deducciones de principio alcanzaron su limite -o ambas situaciones a la vez- y el razonamiento simplemente continuo. Mas que continuar asumiendo estas profesiones de fe, el presente ensayo argumenta que debemos reconocer los limites criticos de la razon y, cada vez que los alcancemos, confiar en la aleatoriedad. Donde los hechos se agotan, donde nuestros principios ya no nos guian, debemos dejar la toma de decision al lanzamiento de moneda, a los dados, a la loteria -en suma, al azar. Este ensayo comienza a explorar lo que ello pueda significar en el ambito del delito y de la pena.
The Star Clusters of the Small Magellanic Cloud: Age Distribution

We present age measurements for 195 star clusters in the Small Magellanic Cloud based on comparison of integrated colors measured from the Magellanic Clouds Photometric Survey with models of simple stellar populations. We find that the modeled nonuniform changes of cluster colors with age can lead to spurious age peaks in the cluster age distribution; that the observed numbers of clusters with age t declines smoothly as t-2.1; that for an assumed initial cluster mass function scaling as M-2, the dependence of the cluster disruption time on mass is proportional to M0.48; that despite the apparent abundance of young clusters, the dominant epoch of cluster formation was the initial one; and that there are significant differences in the spatial distribution of clusters of different ages. Because of limited precision in our age measurements, we cannot address the question of detailed correspondence between the cluster age function and the field star formation history. However, this sample provides an initial guide as to which clusters to target in more detailed studies of specific age intervals.
Recent progress in defining jets

From dedicated QCD studies to new physics background estimation, jets will be everywhere at the LHC. In these proceedings, we discuss two important recent series of improvements. In the first one, we introduce new algorithms and new implementations of previously existing algorithms, in order to cure limitations of their predecessors and to satisfy fundamental requirements. In the second part, we show that it is of prime importance to carefully choose the jet definition — algorithm and parameters — to optimise kinematic reconstructions at the LHC. Noticeably, we show that while at scales around 100 GeV, R ≃ 0.5 is an appropriate choice, clustering at the TeV scale requires R ≃ 1 for optimal efficiency. We finally show that our results are valid in the presence of pileup, provided that a subtraction procedure is applied.
A Very Active Cu-Catalytic System for the Synthesis of Aryl, Heteroaryl, and Vinyl Sulfides

cis-1,2-Cyclohexanediol (L3) has been shown to be an efficient and versatile bidentate O-donor ligand that provides a highly active Cu-catalytic system. It was more effective than diols such as trans-1,2-cyclohexanediol or ethylene glycol. This commercially available cis-1,2-cyclohexanediol ligand facilitated the Cu-catalyzed cross-coupling reactions of alkyl, aryl, or heterocyclic thiols with either alkyl, aryl, heterocyclic, or substituted vinyl halides. This new catalytic system promoted the mild and efficient stereo- and regiospecific synthesis of biologically important vinyl sulfides. The yields obtained using electron-rich substituted vinyl sulfides with this catalyst system are generally 75−98%. Most importantly, this singular catalyst system is extremely versatile and provides entry into a wide range of sulfides. This method is particularly noteworthy given its mild reaction conditions, simplicity, generality, and exceptional level of functional group tolerance.
Mars ascent propulsion on a minimum scale

A concept is presented for a single stage vehicle intended to lift a Mars sample to an orbital rendezvous. At 200 kg liftoff mass, it can potentially be delivered by a Mars Pathfinder size aeroshell. Based on launch vehicle design principles, propellants are pumped from thin-walled low pressure tanks into compact high pressure thrusters. Technical risk is reduced by using non-cryogenic propellants, and by driving piston pumps with heated helium.
An age-graded model for career development education

Abstract Career development is defined as including self-awareness, career-awareness, and career decision making components. This paper attempts then to provide a framework by which educators interested in stimulating career development can choose the learning experiences most likely to have payoffs for different age youth. Eight stages of child development are described in terms of the major behavioral orientation of the child in each. Career development themes are then suggested for each stage along with sample activities and experiences for each theme. Finally, instructional media are recommended for each stage and related to the themes and activities suggested earlier.
Multiple laminar flows through curved pipes

The Dean problem of steady viscous flow through a coiled circular pipe is studied numerically for a large range of Dean number and for several coiling ratios. We find that the solution family, as parameterized by Dean number, has numerous folds or limit points. Four folds and hence five branches of solutions are found. We speculate that infinitely many solutions can exist in this family for some fixed value(s) of D. More resolution and higher accuracy would be required to justify our conjecture and to find the rule of formation of new solution branches.
A formal analysis of information disclosure in data exchange

We perform a theoretical study of the following query-view security problem: given a view V to be published, does V logically disclose information about a confidential query S? The problem is motivated by the need to manage the risk of unintended information disclosure in today's world of universal data exchange. We present a novel information-theoretic standard for query-view security. This criterion can be used to provide a precise analysis of information disclosure for a host of data exchange scenarios, including multi-party collusion and the use of outside knowledge by an adversary trying to learn privileged facts about the database. We prove a number of theoretical results for deciding security according to this standard. We also generalize our security criterion to account for prior knowledge a user or adversary may possess, and introduce techniques for measuring the magnitude of partial disclosures. We believe these results can be a foundation for practical efforts to secure data exchange frameworks, and also illuminate a nice interaction between logic and probability theory.
Sacagawea’s nickname, or the Sacagawea problem

This performance text enacts a critical cultural politics concerning Native American women and their presence in Western mythology. I interrogate the history of Sacagawea and the representation of ...
The large scale geometry of the higher Baumslag-Solitar groups

The Baumslag-Solitar groups: BS(m,n)= are some of the simplest interesting infinite groups which are not lattices in Lie groups. They have been studied in depth from the point of view of combinatorial group theory. It is natural to ask if the geometric approach to the theory of infinite groups, which has been so successful in the study of lattices, can yield any insights in this nonlinear case. We show that in contrast to the solvable groups studied by Farb and Mosher, the groups BS(m,n) with 1<m<n are all quasi-isometric. This generalizes to almost all groups acting on trees with infinite cyclic vertex and edge stabilizers.
Hydrothermal synthesis, structure and thermal stability of diamine templated layered uranyl-vanadates

Six new layered uranyl vanadates (NH{sub 4}){sub 2}[(UO{sub 2}){sub 2}V{sub 2}O{sub 8}] (1), (H{sub 2}EN)[(UO{sub 2}){sub 2}V{sub 2}O{sub 8}] (2), (H{sub 2}DAP)[(UO{sub 2}){sub 2}V{sub 2}O{sub 8}] (3), (H{sub 2}PIP)[(UO{sub 2}){sub 2}(VO{sub 4}){sub 2}].0,8H{sub 2}O (4), (H{sub 2}DMPIP)[(UO{sub 2}){sub 2}V{sub 2}O{sub 8}] (5), (H{sub 2}DABCO)[(UO{sub 2}){sub 2}(VO{sub 4}){sub 2}] (6) were prepared from mild-hydrothermal reactions using 1,2-ethylenediamine (EN); 1,3-diaminopropane (DAP); piperazine (PIP); 1-methylpiperazine (MPIP); 1,4-diazabicyclo[2,2,2]octane (DABCO). The structures of 1, 4, 5 and 6 were solved using single-crystal X-ray diffraction data while the structural models of 2 and 3 were established from powder X-ray diffraction data. In compounds 1, 2, 3 and 5, the uranyl-vanadate layers are built from dimers of edge-shared UO{sub 7} pentagonal bipyramids and dimers of edge-shared VO{sub 5} square pyramids further connected through edge-sharing. In 1 and 3, the layers are identical to that occurring in the carnotite group of uranyl-vanadates. In 2 and 5, the V{sub 2}O{sub 8} dimers differ in orientation leading to a new type of layer. The layers of compound 4 and 6 are built from chains of edge-shared UO{sub 7} pentagonal bipyramids connected by VO{sub 4} tetrahedra and are of uranophane-type anion topology. For the six compounds, the ammonium or organoammonium cationmore » resides in the space between the inorganic layers. Crystallographic data: 1 monoclinic, space group P2{sub 1}/c with a=6.894(2), b=8.384(3), c=10.473(4) A and {beta}=106.066(5){sup o}, 2 monoclinic, space group P2{sub 1}/a with a=13.9816(6), b=8.6165(3), c=10.4237(3) A and {gamma}=93.125(3){sup o}, 3 orthorhombic, space group Pmcn with a=14.7363(8), b=8.6379(4) and c=10.4385(4) A, 4 monoclinic, space group C2/m with a=15.619(2), b=7.1802(8), c=6.9157(8) A and {beta}=101.500(2){sup o}, 5 monoclinic, space group P2{sub 1}/b with a=9.315(2), b=8.617(2), c=10.5246(2) A and {gamma}=114.776(2){sup o}, 6 monoclinic, space group C2/m with a=17.440(2), b=7.1904(9), c=6.8990(8) A and {beta}=98.196(2){sup o}. - Graphical abstract: The three types of layer in layered uranyl-vanadates using diamine as a structure-directing agent.« less
Topological Defects and Highest Energy Cosmic and Gamma Rays

In this paper we review the hypothesis that a substantial part of the cosmic ray flux observed above about 1019 eV may be produced by decaying or annihilating topological defects left over from phase transitions in the early universe at grand unification energy scales (≈ 1016 GeV). Possible signatures of cosmic ray producing defect models are discussed which could be tested experimentally in the near future. We thereby focus on model independent universal spectral properties of the predicted particle fluxes.
A study of the bulk phase transitions of the SU(2) lattice gauge theory with mixed action

Abstract Using the finite size scaling theory, we reexamine the nature of the bulk phase transition in the fundamental-adjoint coupling plane of the SU(2) lattice gauge theory at βA = 1.25 where previous finite size scaling investigations of the deconfinement phase transition showed it to be of first order for temporal lattices with four sites. Our simulations on N4 lattices with N = 6, 8, 10, 12 and 16 show an absence of a first order bulk phase transition. We find the discontinuity in the average plaquette to decrease approximately linearly with N. Correspondingly, the plaquette susceptibility grows a lot slower with the 4-volume of the lattice than expected from a first order bulk phase transition.
Coherency based decomposition and aggregation

The relationship between coherency, area decomposition and aggregation is investigated for a class of models of electromechanical networks, including power system models. It is established that coherency conditions and a physically meaningful area-aggregate, reproducing a prescribed set of system modes, depend on external connections only. Coherency with respect to a set of slowest modes ('slow coherency') and an earlier developed grouping algorithm are used to identify weakly coupled areas, as demonstrated on a 48-machine model of the United States North-East power system.
Quotient Singularities, Integer Ratios of Factorials, and the Riemann Hypothesis

The goal of this paper is to reveal a close connection between the following three subjects that have not been studied together in the past:terminal and canonical cyclic quotient singularities;integer ratios of factorials;Nyman's approach to the Riemann hypothesis.In particular, we notice that the list of the 29 stable quintuples of Mori-Morrison-Morrison coincides, up to the choice of notation, with the list of the 29 step-functions with five terms of Vasyunin. By the work of Rodriguez Villegas and Bober, they are also connected to the algebraic hypergeometric functions. These unexpected connections lead to several interesting open questions.
Universality of Long-Distance AdS Physics from the CFT Bootstrap

We begin by explicating a recent proof of the cluster decomposition principle in AdS�4 from the CFT�3 bootstrap. The CFT argument also computes the leading interactions between distant objects in AdS�4, and we conrm the universal agreement between the CFT bootstrap and AdS gravity in the semi-classical limit. We proceed to study the generalization to CFT2, which requires knowledge of the Virasoro conformal blocks in a lightcone OPE limit. We compute these blocks in a semi- classical, large central charge approximation, and use them to prove a suitably modied theorem. In particular, from the d = 2 bootstrap we prove the existence of large spin operators withxedanomalous dimensions' indicative of the presence of decit angles in AdS3. As we approach the threshold for the BTZ black hole, interpreted as a CFT2 scaling dimension, the twist spectrum of large spin operators becomes dense. Due to the exchange of the Virasoro identity block, primary states above the BTZ threshold mimic a thermal background for light operators. We derive the BTZ quasi- normal modes, and we use the bootstrap equation to prove that the twist spectrum is dense. Corrections to thermality could be obtained from a more rened computation of the Virasoro conformal blocks.
The use of coatings in high temperature battery systems

Abstract Advanced battery systems present a complex set of performance criteria that severely test materials. Coatings can provide an economical means of widening the cost-effective choice of materials to gain improved battery performance and durability. The methodology of coating selection specific to advanced electrochemical energy storage systems is discussed. Experience of NaS battery development is used to illustrate a particular case in which coatings appear to be an element critical to technological advance.
Auto-correlation analysis of high resolution electron micrographs of near-amorphous thin films

Abstract In an attempt to characterize the degree of local ordering of amorphous, near-amorphous and microcrystalline materials from information contained in high resolution electron micrographs, a new method is considered in which auto-correlation functions are obtained from small image regions and then correlated in rotation. By finding the rotation which gives the best correlation with a particular local correlation function showing features of interest and then adding the local auto-correlation functions, an assessment of the local order for the whole image is achieved as a basis for consideration of the form and extent of the order in the specimen. The method has been applied to high resolution transmission electron microscope images recorded in digital form by use of a TV-based image intensifier and digital frame store and later analysed by use of an image processing system. The samples used were thin carbon films having different degrees of graphitization. Even the least-ordered carbon films showed significant local correlations.
Electrostatic effects in DNA stretching

The response of a semiflexible polyelectrolyte chain to stretching in the regimes of moderate and weak screening is studied theoretically, with a special focus on DNA experiments. By using the nonlinear Poisson-Boltzmann description of electrostatic self-interactions of the chain, we explicitly demonstrate the applicability of the concept of effective charge to certain aspects of the problem. This charge can be extracted from the far-field asymptotic behavior of the electrostatic potential of the fully aligned chain. Surprisingly, in terms of the effective charge, the electrostatically renormalized persistence length can be formally described by the classical Odijk-Skolnick-Fixman formula, whose domain of applicability is normally limited to the linearized Debye-H\"uckel (DH) approximation. However, the short-scale behavior of the chain in the nonlinear regime deviates from the of DH-based result, even upon charge renormalization. This difference is revealed in the calculated stretching curves for strongly charged DNA. These results are in good agreement with recent experiments. In the limit of weak screening we predict the elastic response to have a distinctive two-stage character, with a peculiar intermediate ``unstretchable'' regime.
Active unsteady aerodynamic suppression of rotating stall in an incompressible flow centrifugal compressor with vaned diffuser

A mathematical model is developed to analyze the suppression of rotating stall in an incompressible flow centrifugal compressor with a vaned diffuser, thereby addressing the important need for centrifugal compressor rotating stall and surge control. In this model, the precursor to to instability is a weak rotating potential velocity perturbation in the inlet flow field that eventually develops into a finite disturbance. To suppress the growth of this potential disturbance, a rotating control vortical velocity disturbance is introduced into the impeller inlet flow. The effectiveness of this control is analyzed by matching the perturbation pressure in the compressor inlet and exit flow fields with a model for the unsteady behavior of the compressor. To demonstrate instability control, this model is then used to predict the control effectiveness for centrifugal compressor geometries based on a low speed research centrifugal compressor. These results indicate that reductions of 10 to 15 percent in the mean inlet flow coefficient at instability are possible with control waveforms of half the magnitude of the total disturbance at the inlet.
MARVEL: a system that recognizes world locations with stereo vision

MARVEL is a system that supports autonomous navigation by building and maintaining its own models of world locations and using these models and stereo vision input to recognize its location in the world and its position and orientation within that location. The system emphasizes the use of simple, easily derivable features for recognition, whose aggregate identifies a location, instead of complex features that also require recognition. MARVEL is designed to be robust with respect to input errors and to respond to a gradually changing world by updating its world location models. In over 1000 recognition tests using real-world data, MARVEL yielded a false negative rate under 10% with zero false positives. >
Palomar/Las Campanas Imaging Atlas of Blue Compact Dwarf Galaxies. I. Images and Integrated Photometry

We present B, R, and Hα images for a total of 114 nearby galaxies (v_helio -21 mag), peak surface brightness (μ_B,peak < 22 mag arcsec-2), and color at the peak surface brightness (μ^_B,peak - μ_R,peak ≤1). Hα emission is detected in all but three sample galaxies. Typical color, absolute magnitude, and Hα luminosity are (B-R) = 0.7 ± 0.3 mag, M_B = -16.1 ± 1.4 mag, and log (L_Hα) = 40.0 ± 0.6 (ergs s^-1). Galaxies morphologically classified as nE and iE BCDs within our sample show lower Hα equivalent widths and redder colors, on average, than the iI- and i0-type BCDs. For most of the galaxies the presence of an evolved stellar population is required to explain their observed properties; only the most metal-poor BCDs (e.g., I Zw 18, Tol 65) are still compatible with a pure, young burst. The flux-calibrated and WCS-compliant images in this Atlas are individually available through the NASA/IPAC Extragalactic Database (NED) image server and collectively through a dedicated Web page.
RNA Polymerase III Transcription

Remarkable progress has been made in defining the functional significance of the protein-DNA interactions involved in transcription complex formation on yeast tRNA and 5S RNA genes. This new information leads to a re-evaluation of how the class III gene transcription machinery operates.
Organic metals: Synthesis, structure and properties of (BMDT-TTF)2Au(CN)2

Abstract A novel 2:1 salt, di[bis(methylenedithio)-tetrathiafulvalene] dicyanoaurate(I), (BMDT-TTF)2Au(CN)2, has been prepared by electrochemical oxidation in 0.016 M (C4H9)4N Au(CN)2/chlorobenzene. Single crystal X-ray diffraction studies indicate that the salt is monoclinic, P21/a, with a = 10.824(7), b = 8.420(5) c = 15.614(8) A and β = 102.46(4)° having a unit cell volume of 1390 A3 and two molecules per unit cell exhibiting an unusual packing motif. The four-probe d.c. electrical conductivity was found to be metallic at room temperature, having a value of nearly 300 (ohm cm)−1. Electron spin resonance studies show that above 70 K the spin susceptibility is relatively large (7 × 10−4 emu/mole) and independent of temperature, consistent with the Pauli susceptibility for a metal.
Electron-rich O=PR3 compounds: Catalysts for alcohol silylation

The catalytic effect of a group of R3P=O compounds was studied in a mild procedure for the silylation of primary alcohols, secondary alcohols, hindered secondary alcohols, and of hindered phenols in the presence of t-butyldimethylsilyl chloride (TBDMSCl) and t-butyldiphenylsilyl chloride (TBDPSCl). It was found that R3P=O is an efficient catalyst in such reactions when R is a good electron-donating group, such as Me2N or n-Bu and as an NMe(CH2) moiety in N(CH2CH2NMe)3P=O (3). However, R3P=O is a weak or ineffective catalyst when R is a poor electron-donating group, such as Ph or O-n-Bu or as a CH2N-o-CH2C5H4N moiety in N(CH2CH2N-o-CH2C5H4N)3P=O. Compound 3, synthesized by oxidation of commercially available N(CH2CH2NMe)3P, displayed the best catalytic properties for alcohol silylation in terms of efficiency, stability, and safety. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:21–26, 2001
Subspace-augmented MUSIC for joint sparse recovery with any rank

We propose a robust and efficient algorithm for the recovery of the joint support in compressed sensing with multiple measurement vectors (the MMV problem). When the unknown matrix of the jointly sparse signals has full rank, MUSIC is a guaranteed algorithm for this problem, achieving the fundamental algebraic bound on the minimum number of measurements. We focus instead on the unfavorable but practically significant case of rank deficiency or bad conditioning. This situation arises with limited number of measurements, or with highly correlated signal components. In this case MUSIC fails, and in practice none of the existing MMV methods can consistently approach the algebraic bounds. We propose subspace-augmented MUSIC, which overcomes these limitations by combining the advantages of both existing methods and MUSIC. It is a computationally efficient algorithm with a performance guarantee.
Structural changes in the cointegrated vector autoregressive model

Abstract This paper generalizes the cointegrated vector autoregressive model of Johansen (J. Econom. Dyn. Control 12 (1988) 231–254) to allow for structural changes. We take the time of the change points and the number of cointegration relations as given. Estimation under various hypotheses is made possible by a new estimation technique, which makes it simple to derive a number of interesting likelihood ratio tests. For example, one can test for m structural changes against m + k structural changes, or test linear parameter restrictions in the presence of structural changes. The asymptotic distribution of the likelihood ratio statistic is χ 2 in both cases. The model is applied to US term structure data, and structural changes in September 1979 and October 1982, which coincide with large changes in the Fed's policy, are found to be significant. After accounting for these structural changes, we cannot, contrary to previous studies, reject the long-run implication of the expectations hypothesis.
Control of laminar separation over airfoils by acoustic excitation

The effect of acoustic excitation in reducing laminar separation over two-dimensional airfoils at low angles of attack is investigated experimentally. Airfoils of two different cross sections, each with two different chord lengths, are studied in the chord Reynolds number range of 25,000 is less than R sub c is less than 100,000. While keeping the amplitude of the excitation induced velocity perturbation a constant, it is found that the most effective frequency scales as U (sup 3/2) (sub infinity). The parameter St/R (sup 1/2)(sub c), corresponding to the most effective f sub p for all the cases studied, falls in the range of 0.02 to 0.03, St being the Strouhal number based on the chord.