cssi/SciSciGPT-SciSciNet huggingface dataset:
Percutaneous Radiofrequency Ablation of Renal Cell Carcinoma

Conventional curative therapy for renal cell carcinoma has been open nephrectomy. However, several less invasive and/or nephron-sparing procedures have been developed as alternatives in selected patients. The newest of these therapeutic modalities involves percutaneous image-guided ablation with straight or expandable needle applicators that deposit energy. Radiofrequency ablation is the modality for which there is the largest reported experience with percutaneous application, and involves the use of electrical current to generate frictional heating of tissue. Animal studies confirm the ability of radiofrequency ablation to cause regions of necrosis within normal kidney and in VX2 tumors. Clinically, radiofrequency ablation of small renal cell carcinoma is increasingly being performed in selected patients who are not ideal surgical candidates. Results are excellent for small exophytic tumors, but successful treatment is less likely as tumor size increases or the location becomes more central. Complete treatment of most tumors requires one or more overlapping ablations with the needle electrodes positioned so as to cause necrosis in the entire volume of tumor. The number of overlapping ablations and the position of the needle electrodes vary based on tumor size and geometry. For very large tumors, pre-ablation catheter embolization may enhance the results of ablation by decreasing blood flow and perfusion mediated cooling. Following ablation, imaging with CT or MR is performed to assess the result and to diagnose any residual tumor so that it can be treated. Because the tumor remains in situ, imaging follow-up continues indefinitely. The complication rate of radiofrequency ablation is favorable when compared to surgical techniques. Long-term survival data are not yet available.
A fluorescein tracer release experiment in the hydrothermally active crater of Vailulu'u volcano, Samoa

[1] On 3 April 2001, a 20 kg point source of fluorescein dye was released 30 m above the bottom of the active summit caldera of Vailulu'u submarine volcano, Samoa. Vailulu'u crater is 2000 m wide and at water depths of 600–1000 m, with the bottom 200 m completely enclosed; it thus provides an ideal site to study the hydrodynamics of an active hydrothermal system. The magmatically driven hydrothermal system in the crater is currently exporting massive amounts of particulates, manganese, and helium. The dispersal of the dye was tracked for 4 days with a fluorimeter in tow-yo mode from the U.S. Coast Guard icebreaker Polar Sea. Lateral dispersion of the dye ranged from 80 to 500 m d−1; vertical dispersion had two components: a diapycnal diffusivity component averaging 21 cm2 s−1, and an advective component averaging 0.025 cm s−1. These measurements constrain the mass export of water from the crater during this period to be 8−1.3+4.6 × 107 m3 d−1, which leads to a “turnover” time for water in the crater of ∼3.2 days. Coupled with temperature data from CTD profiles and Mn analyses of water samples, the power output from the crater is 610−100+350 MW, and the manganese export flux is ∼240 kg d−1. The Mn/Heat ratio of 4.7 ng J−1 is significantly lower than ratios characteristic of hot smokers and diffuse hydrothermal flows on mid-ocean ridges and points to phase separation processes in this relatively shallow hydrothermal system.
Dihedral group frames which are maximally robust to erasures

Let be a natural number larger than two. Let be the Dihedral group, and an -dimensional unitary representation of acting in as follows. and for . For any representation which is unitarily equivalent to we prove that when is prime, there exists a Zariski open subset of such that for any vector any subset of cardinality of the orbit of under the action of this representation is a basis for . However, when is even, there is no vector in which satisfies this property. As a result, we derive that if is prime, for almost every (with respect to Lebesgue measure) vector in , the -orbit of is a frame which is maximally robust to erasures. We also consider the case where is equivalent to an irreducible unitary representation of the Dihedral group acting in a vector space and we provide conditions under which it is possible to find a vector such that has the Haar property.
Kinematics and Mass Profile of AWM 7

We have measured 492 redshifts (311 new) in the direction of the poor cluster AWM 7 and have identified 179 cluster members (73 new). We use two independent methods to derive a self-consistent mass profile, under the assumptions that the absorption-line galaxies are virialized and that they trace an underlying Navarro, Frenk, & White (NFW) dark matter profile: (1) we fit such an NFW profile to the radial distribution of galaxy positions and to the velocity dispersion profile; (2) we apply the virial mass estimator to the cluster. With these assumptions, the two independent mass estimates agree to ~15% within 1.7 h-1 Mpc, the radial extent of our data; we find an enclosed mass ~(3 ± 0.5) × 1014 h-1 M⊙. The largest potential source of systematic error is the inclusion of young emission-line galaxies in the mass estimate. We investigate the behavior of the surface term correction to the virial mass estimator under several assumptions about the velocity anisotropy profile, still within the context of the NFW model, and remark on the sensitivity of derived mass profiles to outliers. We find that one must have data out to a large radius in order to determine the mass robustly, and that the surface term correction is unreliable at small radii.
Prediction of Vapor Pressures of Hydrocarbons and Halohydrocarbons from Molecular Structure with a Computational Neural Network Model

Computational methods are used to link the molecular structures of 352 hydrocarbons and halohydrocarbons to their vapor pressures at 25 °C. The data are from the Design Institute for Physical Property Data (DIPPR) database. Vapor pressures of the compounds range from −1.016 log(VP) to +6.65 log(VP) with VP in pascals. Multiple linear regression was used to develop linear statistical models. A 7:3:1 computational neural network (CNN) was used to create a nonlinear model best suited for prediction of vapor pressure. The root-mean-square errors associated with the training, cross-validation, and prediction set compounds used for this CNN model were 0.163, 0.163, and 0.209 log units.
A Theoretical and Experimental Investigation of a Gas-Operated Bearing Damper for Turbomachinery: Part I—Theoretical Model and Predictions

This is the first (Part I) of two papers describing recent results of the research program directed at developing a vibration damper suitable for high-temperature turbomachinery applications. It is expected that such dampers will replace squeeze-film dampers, which use oil as the working fluid and have limitations at higher temperatures. A novel gas-operated bearing damper has been evaluated analytically and experimentally for its damping characteristics. A theory based on the isentropic assumptions predicts the damper performance characteristics reasonably well. A maximum damping level of 2311 N-m/s (13.2 lb-s/in.) at a frequency of 100 Hz was measured with a single actuator of the gas damper. Since many such actuators could be placed circumferentially around the squirrel cage, considerable damping levels can be realized. The study also shows that significantly higher damping levels can be achieved by modifying the current design. Part I describes the theoretical model that has been developed based on isentropic assumptions. This model is an improved version of the previous theory (Vance et al., 1991) and includes the supply groove effects, dynamic area changes of the inlet feeding holes, and the effects of flow choking on damper behavior. The governing equations are derived and theoretical predictions using these equations have been made for two hardware designs that were experimentally investigated (see Part II for experimental results).
The Luminescence of Zinc Sulphide Under the Action of Alpha, Beta and Gamma-Rays

The luminescence of zinc sulphide under the action of $\ensuremath{\alpha}$, $\ensuremath{\beta}$ and $\ensuremath{\gamma}$-rays was studied with an especially designed brass capsule. The zinc sulphide was exposed to the $\ensuremath{\alpha}$-rays or $\ensuremath{\beta}$ and $\ensuremath{\gamma}$-rays, or $\ensuremath{\alpha}$, $\ensuremath{\beta}$ and $\ensuremath{\gamma}$-rays from radium or its products, while the luminescent material and the exciting agent were kept separate. In this way the effect of these rays upon the luminescent material was observed, separately and collectively. The experiment was made under practically constant temperature. The luminosity time curves for the three types of capsules were consistent in characteristics. It was found that for a time there was a definite increase in brightness; then the luminescence decreased under the constant action of the rays and rose again to a second maximum. This was followed by gradual decrease with time as long as observations were taken. The decay of luminescence of zinc sulphide, after the removal of the radio active source, showed that the decay curve is not of the type whose ordinate can be expressed by a single exponential term.
An inverse source problem in radiative transfer with partial data

The inverse source problem for the radiative transfer equation is considered, with partial data. Here it is shown that under certain smoothness conditions on the scattering and absorption coefficients, one can recover sources supported in a certain subset of the domain, which we call the visible set. Furthermore, it is shown for an open dense set of C∞ absorption and scattering coefficients that one can recover the part of the wavefront set of the source that is supported in the microlocally visible set, modulo a function in the Sobolev space Hk for k arbitrarily large. This is an extension to the full data case, where the complete recovery of an arbitrary source has been shown.
Growth Mixture Modeling: Identifying and Predicting Unobserved Subpopulations With Longitudinal Data

An important limitation of conventional latent-growth modeling (LGM) is that it assumes that all individuals are drawn from one or more observed populations. However, in many applied-research situations, unobserved subpopulations may exist, and their different latent trajectories may be the focus of research to test theory or to resolve inconsistent prior research findings. Conventional LGM does not help to identify and predict these unobserved subpopulations. This article introduces the growth-mixture modeling (GMM) method for these purposes. Given that GMM handles longitudinal data (i.e., nesting of time observations within individuals) and identifies unobserved subpopulations (i.e., the nesting of individuals within latent classes), GMM can be construed as a multilevel modeling technique. The modeling procedure of GMM is illustrated on a simulated data set. Steps in the modeling process are highlighted and limitations, cautions, recommendations, and extensions of using GMM are discussed. Technical refe...
Coordination chemistry of chelating nitrogen ligands with tungsten carbonyl nitriles

Abstract The reactions of a series of Schiff base ligands (1–4) prepared by condensation of pyridine-2-carboxaldehyde and 2-X-anilines (X = F, Cl, Br, OMe) with W(CO)3(RCN)3 results in the formation of deeply coloured complexes W(CO)3(1–4)(NCR) which readily react with carbon monoxide to afford W(CO)4(1–4). The ligand 5, prepared from pyridine-2-carboxaldehyde and N,N-dimethylethylenediamine, coordinates to W(CO)3 through the conjugated pyridine—imine chelate to afford complexes with a pendant dimethylamino group which reacts with electrophiles. Of the ligands studied, only the bis-amine, pyridine ligand 8, coordinates to W(CO)3 in a tridentate manner. These reactions provide insight into the geometric and electronic factors which influence coordination of nitrogen containing ligands at a fac-tricarbonyl metal centre.
A machine-independent debugger—revisited

Most debuggers are notoriously machine-dependent, but some recent research prototypes achieve varying degrees of machine-independence with novel designs. Cdb, a simple source-level debugger for C, is completely independent of its target architecture. This independence is achieved by embedding symbol tables and debugging code in the target program, which costs both time and space. This paper describes a revised design and implementation of cdb that reduces the space cost by nearly one-half and the time cost by 13% by storing symbol tables in external files. A symbol table is defined by a 31-line grammar in the Abstract Syntax Description Language (ASDL). ASDL is a domainspecific language for specifying tree data structures. The ASDL tools accept an ASDL grammar and generate code to construct, read, and write these data structures. Using ASDL automates implementing parts of the debugger, and the grammar documents the symbol table concisely. Using ASDL also suggested simplifications to the interface between the debugger and the target program. Perhaps most important, ASDL emphasizes that symbol tables are data structures, not file formats. Many of the pitfalls of working with low-level file formats can be avoided by focusing instead on high-level data structures and automating the implementation details. Microsoft Research Microsoft Corporation One Microsoft Way Redmond, WA 98052 http://www.research.microsoft.com/
Risk, managerial effort, and project choice

Abstract In our model risk-neutral shareholders need to motivate a manager to select among projects with different risks, and to work hard in implementing the chosen project. Curvature of the manager's compensation contract as a function of profit affects his attitude toward project risk. The optimal curvature depends on the trade-off between controlling project risk and motivating effort. The analysis predicts greater option-based compensation when there are desirable risky growth opportunities (proxied by Tobin's q or R&D expenditures) and less option compensation when there are effective monitoring institutions (such as outside directors and bank lenders).
Strategies for in vivo imaging of enzyme activity: an overview and recent advances

Imaging of enzyme activity in living subjects promises many applications in both basic and translational researches from helping elucidate the enzyme function and mechanism in biology to better disease detection and monitoring, but the complexity and dynamics of enzymatic reactions in living systems present unique challenges for probe design. This critical review examines the approaches in recent literature to in vivo imaging of the activity of a variety of enzyme targets with an emphasis on the chemical perspective of probe design, structure and function. Strategies for designing enzyme-activated probes based on a variety of molecular scaffolds including small molecules, organic and inorganic nanoparticles, and genetically encoded proteins for commonly used molecular imaging modalities—whole body optical (fluorescence, bioluminescence) imaging, magnetic resonance imaging, and radionuclide-based tomographic imaging, are critically evaluated. Recent advances in combining multiple modalities to imaging enzyme activity in living subjects are also highlighted (255 references).
From Radio to X-Ray: Flares on the dMe Flare Star EV Lacertae

We present the results of a campaign to observe flares on the M dwarf flare star EV Lacertae over the course of two days in 2001 September, utilizing a combination of radio continuum, optical photometric and spectroscopic, ultraviolet spectroscopic, and X-ray spectroscopic observations to characterize the multiwavelength nature of flares from this active, single, late-type star. We find flares in every wavelength region in which we observed. A large radio flare from the star was observed at both 3.6 and 6 cm and is the most luminous example of a gyrosynchrotron flare yet observed on a dMe flare star. The radio flare can be explained as encompassing a large magnetic volume, comparable to the stellar disk, and involving trapped electrons that decay over timescales of hours. Flux enhancements at 6 cm accompanied by highly negatively circularly polarized emission (?c ? -100%) imply that a coherent emission mechanism is operating in the corona of EV Lac. There are numerous optical white-light flares, and yet no signature of emission-line response from the chromosphere appears. Two small ultraviolet enhancements differ in the amount of nonthermal broadening present. There are numerous X-ray flares occurring throughout the observation, and an analysis of undispersed photons and grating events reveals no evidence for abundance variations. Higher temperatures are present during some flares; however, the maximum temperature achieved varies from flare to flare. There is no evidence for density variations during any flare intervals. In the multiwavelength context, the start of the intense radio flare is coincident with an impulsive optical U-band flare, to within 1 minute, and yet there is no signature of an X-ray response. There are other intervals of time when optical flaring and UV flaring is occurring, but these cannot be related to the contemporaneous X-ray flaring: the time-integrated luminosities do not match the instantaneous X-ray flare luminosity, as one would expect for the Neupert effect. We investigate the probability of chance occurrences of flares from disparate wavelength regions producing temporal coincidences but find that not all the flare associations can be explained by a superposition of flares due to a high flaring rate. We caution against making causal associations of multiwavelength flares based solely on temporal correlations for high flaring rate stars such as EV Lac.
Total syntheses of bryostatins: synthesis of two ring-expanded bryostatin analogues and the development of a new-generation strategy to access the C7-C27 fragment.

This paper reports the synthesis of novel ring-expanded bryostatin analogues. By carefully modifying the substrate, a selective and high-yielding Ru-catalyzed tandem enyne coupling/Michael addition was employed to construct the northern fragment. A ring-closing metathesis was utilized to form the 31-membered macrocycle of the analogue. These ring-expanded bryostatin analogues possess anticancer activity against several cancer cell lines. Given the difficulty of forming the C16-17 olefin in the late stage, we also describe our development of a new-generation strategy to access the C7-C27 fragment containing both the B- and C-ring subunits.
Modeling the digital earth in VRML

This paper describes the representation and navigation of large, multi-resolution, georeferenced datasets in VRML97. This requires resolving nontrivial issues such as how to represent deep level of detail hierarchies efficiently in VRML; how to model terrain using geographic coordinate systems instead of only VRML's Cartesian representation; how to model georeferenced coordinates to sub-meter accuracy with only single-precision floating point support; how to enable the integration of multiple terrain datasets for a region, as well as cultural features such as buildings and rods; how to navigate efficiently around a large, global terrain dataset; and finally, how to encode metadata describing the terrain. We present solutions to all of these problems. Consequently, we are able to visualize geographic dat ain the order of terabytes or more, from the globe down to millimeter resolution, and in real-time, using standard VRML97.
Learning and reasoning by analogy

We use analogy when we say something is a Cinderella story and when we learn about resistors by thinking about water pipes. We also use analogy when we learn subjects like economics, medicine, and law. This paper presents a theory of analogy and describes an implemented system that embodies the theory. The specific competence to be understood is that of using analogies to do certain kinds of learning and reasoning. Learning takes place when analogy is used to generate a constraint description in one domain, given a constraint description in another, as when we learn Ohm's law by way of knowledge about water pipes. Reasoning takes place when analogy is used to answer questions about one situation, given another situation that is supposed to be a precedent, as when we answer questions about Hamlet by way of knowledge about Macbeth.
Do Atlanta residents value MARTA? Selecting an autoregressive model to recover willingness to pay

Abstract Understanding homeowners’ marginal willingness-to-pay (MWTP) for proximity to public transportation infrastructure is important for planning and policy. Naive estimates of MWTP, however, may be biased as a result of spatial dependence, spatial correlation, and/or spatially endogenous variables. In this paper we discuss a class of spatial autoregressive models that control for these spatial effects, and apply them to sample data collected for the Atlanta, Georgia housing market. We provide evidence that a general-to-specific model selection methodology that relies on the generality of the spatial Durbin model (SDM) should be preferred to the classical specific-to-general methodology that begins with an assumption of no spatial effects. We show that applying the SDM raises the estimate of MWTP for transit proximity in Atlanta but also widens its confidence interval, relative to ordinary linear regression. This finding may have implications for risk estimations in land value capture forecasts and transportation policy decisions.
Preparation of fluoroalkenes from fluoroacetonitrile

Abstract A fluorocyanophosphate prepared from fluoroacetronitrile at low temperature reacts with aromatic aldehydes in a modified Wittig procedure to give fluoro-cyanoalkenes in moderate yield.
Minimal surface representations of virtual knots and links

Kuperberg (15) has shown that a virtual knot diagram corre- sponds (up to generalized Reidemeister moves) to a unique embedding in a thickened surface of minimal genus. If a virtual knot diagram is equivalent to a classical knot diagram then this minimal surface is a sphere. Using this result and a generalised bracket polynomial, we develop methods that may determine whether a virtual knot diagram is non-classical (and hence non-trivial). As examples we show that, except for special cases, link dia- grams with a single virtualization and link diagrams with a single virtual crossing are non-classical. AMS Classification 57M25, 57M27; 57N05
Performance modeling and characterization of large last level caches

For each different cache configuration, we identified parametric functions to characterize the probability density of statistics related to cache performance. Observe that, the parameters (α,β) in (1) and (a, b, n) in (2) depend on cache configuration. We next need to study the sensitivity of the parameters in the density function to cache configuration parameters. Once this is established we can express the distribution of CRT, SRT and IHT in terms of cache size and line size alongwith workload specific constants. Having known these distributions, T crt , T srt and T iht and hence m from Model-A and Model-B can be written as an explicit function of cache size and line size for a given workload.
Evidence for new physics from clusters

The abundance of local clusters is a traditional way to derive the amplitude of matter fluctuations, commonly speci- fied by σ8 ,b ut which suffers from a systematic uncertainty arising from the lack of accurate knowledge of the mass temperature relation. In the present work, by assuming that the observed baryon content of clusters is representative of the universe, we show that the mass temperature relation (M − T ) can be specified for any cosmological model. WMAP constraints on the baryonic content of the Universe and the ΩM − H0 relation allows one further improvement in tightening this M − T relation. This ap- proach allows one to remove most of the above uncertainty, and to provide an estimation of σ8 whose uncertainty is essentially statistical. The values we obtain are fortuitously almost independent of the matter density of the Universe (σ8 ∼ 0.6−0.63) with an accuracy better than 5%. Quite remarkably, the amplitude of matter fluctuations can be also tightly constrained to similar accuracy from existing CMB measurements alone, once the dark matter content is specified. However, the amplitude inferred in this way in a concordance model (ΛCDM) is significantly larger than the value derived from the above method based on X-ray clusters. Such a discrepancy would almost disappear if the actual optical thickness of the Universe was 0 but could also be alleviated from more exotic solutions: for instance the existence of a new non-baryonic light dark component in the Universe as massive neutrinos, with Ωd ∼ 0.01−0.03. However, recent other indications of σ8 favor a high normalization. In this case, the assumption that the baryonic content observed in clusters actually reflects the primordial value has to be relaxed: either there exists a large baryonic dark component in the Universe with Ωd ∼ 0.01−0.03 ∼ 0.5Ωb or baryons in clusters have undergone a large depletion during the formation of these structures. We concluded that the baryon fraction in clusters is not representative and therefore that an essential piece of the physics of baryons in clusters is missing in standard structure formation scenario.
Environmental Regulation with Innovation and Learning: Rules versus Discretion

We analyze a model of environmental regulation with learning about environmental damages and endogenous choice of emissions abatement technology by a polluting firm. We compare environmental policy under discretion, in which policy is updated upon learning new information, versus under rules, in which policy is not updated. When investment in abatement technology is made prior to the resolution of uncertainty, neither discretion nor rules with either taxes or standards achieve an efficient solution. When there is little uncertainty, rules are superior to discretion because discretionary policy gives the firm an incentive to distort investment in order to influence future regulation. However, when uncertainty is large, discretion is superior to rules because it allows regulation to incorporate new information. Under discretionary policy, taxes are superior to standards regardless of the relative slopes of marginal costs and marginal damages.
An ISO market settlement design validation approach using probabilistic market simulation study techniques

In the independent system operator organizations, settlement activity is an integral part of the market operation. One of the key components for measuring independent system operator market operational design correctness is to analyze how well market price signals create incentives and/or penalties for creating an efficient market to achieve the design goals under uncertainties due to unpredictable market conditions. The market settlement rule is an important vehicle to implement such price signals. This paper presents an approach for a probabilistic method to validate settlement systems design using probabilistic techniques for independent system operator market simulation. In addition, the paper presents critical comments on various differences in settlement design approach.
Synthesis of alcohols via mild oxidation of perfluoroethylstannanes

Abstract Alkaline H 2 O 2 oxidizes perfluoroethyl-substituted stannanes to the corresponding alcohols with retention of configuration.
Accurately Sized Test Statistics with Misspecified Conditional Homoskedasticity

We study the finite-sample performance of test statistics in linear regression models where the error dependence is of unknown form. With an unknown dependence structure, there is traditionally a trade-off between the maximum lag over which the correlation is estimated (the bandwidth) and the amount of heterogeneity in the process. When allowing for heterogeneity, through conditional heteroskedasticity, the correlation at far lags is generally omitted and the resultant inflation of the empirical size of test statistics has long been recognized. To allow for correlation at far lags, we study the test statistics constructed under the possibly misspecified assumption of conditional homoskedasticity. To improve the accuracy of the test statistics, we employ the second-order asymptotic refinement in Rothenberg [Approximate power functions for some robust tests of regression coefficients, Econometrica 56 (1988), pp. 997–1019] to determine the critical values. The simulation results of this paper suggest that wh...
Life and Evolution in Computers

This paper argues for the possibility of 'artificial life' and computational evolution, first by discussing (via a highly simplified version) John von Neumann's self-reproducing automation and then by presenting some recent work focusing on computational evolution, in which 'cellular automata', a form of parallel and decentralized computing system, are evolved via 'genetic algorithms'. It is argued that such in silico experiments can help to make sense of the question of whether we can eventually build computers that are intelligent and alive.
Direct determination of quadrupolar and dipolar NMR correlation times from spin-lattice and spin-spin relaxation rates

Recent developments in the mathematical solution of nuclear magnetic resonance (NMR) relaxation equations describing rotational motion allow investigators to determine correlation times, τ, on the nanosecond time scale. NMR rotational correlation equations for quadrupolar and dipolar relaxation can be solved for nuclei in moderately viscous media using R2/R1 ratios. In the case of quadrupolar nuclei, the R2/R1 ratios can be used to solve the rotational correlation equations directly. For dipolar nuclei including 1H, 13C, 15N, 19F, 31P, and 113Cd, it is necessary to solve the rotational correlation time equations at each magnetic field strength using iterative methods. The resulting solutions are fitted to pairs of polynomials (R2/R1=1.1–20 and 20–1200) at individual magnetic field strengths (4.7, 6.35, 7.05, 9.4, 11.75, and 14.1 T). The investigator determines the R2/R1 ratio at a specific magnetic field and uses the appropriate polynomial to determine the rotational correlation time. Correlation times are used to study molecular interactions where dipolar relaxtion occurs and to determine quadrupole coupling constants, χ, where quadrupole relaxation is the predominant mechanism. 1H-NMR diffusion constants can be compared with NMR correlation times to provide data about the transport properties of the system being studied. ©1999 John Wiley & Sons, Inc. Concepts Magn Reson 11: 51–60, 1999
Positive position feedback control for large space structures

A new technique for vibration suppression in large space structures is investigated in laboratory experiments on a thin cantilever beam. This technique, called Positive Position Feedback, makes use of generalized displacement measurements to accomplish vibration suppression. Several features of Positive Position Feedback make it attractive for the large space structure control environment: The realization of the controller is simple and straightforward. Global stability conditions can be derived which are independent of the dynamical characteristics of the structure being controlled, i.e., all spillover is stabilizing. The method cannot be destabilized by finite actuator dynamics, and the technique is amenable to a strain-based sensing approach. The experiments control the first six bending modes of a cantilever beam, and make use of piezoelectric materials for actuators and sensors, simulating a piezoelectric active-member. The modal damping ratios are increased by factors ranging from 2 to 130.
Guardian: Decentralized control of an embedded multimicroprocessor

Guardian is a real-time, multimicroprocessor operating system intended to be a research testbed for experimentation with decentralized control. It was designed in a Pascal-like language for a target multimicroprocessor that contains six microcomputer processing elements and twelve shared memories fully interconnected by a crossbar switch. Each processing element in the host multimicroprocessor executes Gaurdian tasks that perform shared memory reclamation, internodal communication, health monitoring, task scheduling, fault containment, and distributed debugging. Each node also supports application-callable software primitives for realtime process control, message-based interprocess communication, shared data structure management, and exception handling. The primary goal of Guardian is to demonstrate hard real-time decentralized control of an embedded multimicroprocessor.
Attempted syntheses of aminofluorothiophenes

It appeared that a key intermediate for 2-amino-3-fluorothiophene (1), methyl 3-fluorothiophene-2-carboxylate (5), had been prepared by a Schiemann reaction of the 3-diazonium salt (6) in xylenes. This report was not correct. Gomberg coupling products 7 with o-xylene are actually formed. We were able to prepare 5 by using special conditions for the Schiemann reaction. The hydrazide derivative of 5 failed to give 1 under Curtius reaction conditions. Two new acetamidofluorothiophene compounds were prepared using SelectfluorTM as the fluorinating agent, but no aminofluorothiophenes 1-3 or salts could be obtained by acidic hydrolysis of either amide.
Mechanical Implications of High Current Densities in Flip-chip Solder Joints

We studied the electromigration damage to flip-chip solder joints of eutectic Sn/Pb under current stressing at room temperature with a current density of 1.3 × 104 A/cm2. The height of the solder joints was 100 μm. The mass accumulation near the anode side and the void nucleation near the cathode were observed during current stressing. In the preliminary experiment, the surface marker movement technique was used to measure the atomic flux driven by electromigration and to calculate the product of effective charge number and diffusivity (D × Z*) of the solder. Subsequent experiments revealed that the presence of thermomigration due to joule heating makes the extraction of the product of effective charge number and diffusivity erroneous when using marker movement technique.
An adaptive power system equivalent for real-time estimation of stability margin using phase-plane trajectories

This paper studies real-time estimation of stability margin of a power system under disturbances by continuous measurement data. The paper presents a Ball-On-Concave-Surface (BOCS) mechanics system as a power system's adaptive equivalent representing its real-time status and the stability region about a monitored variable. The parameters of the equivalent are adaptive to the operating condition and can online be identified from the phase-plane trajectories of the monitored variable. Accordingly, the stability margin and risk of instability can be estimated. Case studies on a two-generator system and a 179-bus system show that the BOCS system can be applied either locally or for wide-area stability monitoring in real-time calculation of stability margin. This paper proposes a new idea for using real-time measurements to develop and identify a power system's adaptive equivalent as a basis for online prediction of instability.
Eighth workshop on information integration on the web (IIWeb 2011)

The goal of the Eighth Workshop on Information Integration on the Web (IIWeb 2011), held in conjunction with WWW 2011 on March 28th, 2011 at Hyderabad, India was to bring together academic researchers and industry practitioners in Information Integration. This edition had a special focus on challenges brought out in integrating cyber physical systems (CPS) for building a sustainable ecosystem for life on our planet. The workshop program consisted of three invited talks and six presentations from authors of accepted papers, all focussed in the area of cyber physical system creation for smarter traffic, intelligence gathering etc. The six papers were picked from a pool of twenty two papers submitted to the workshop after a peer review process. The workshop attracted about 30 registered delegates of WWW 2011.
Dark Energy and the Accelerating Universe

Ten years ago, the discovery that the expansion of the universe is accelerating put in place the last major building block of the present cosmological model, in which the universe is composed of 4% baryons, 20% dark matter, and 76% dark energy. At the same time, it posed one of the most profound mysteries in all of science, with deep connections to both astrophysics and particle physics. Cosmic acceleration could arise from the repulsive gravity of dark energy—for example, the quantum energy of the vacuum—or it may signal that general relativity (GR) breaks down on cosmological scales and must be replaced. We review the present observational evidence for cosmic acceleration and what it has revealed about dark energy, discuss the various theoretical ideas that have been proposed to explain acceleration, and describe the key observational probes that will shed light on this enigma in the coming years.
Learning to Match Names Across Languages

We report on research on matching names in different scripts across languages. We explore two trainable approaches based on comparing pronunciations. The first, a cross-lingual approach, uses an automatic name-matching program that exploits rules based on phonological comparisons of the two languages carried out by humans. The second, monolingual approach, relies only on automatic comparison of the phonological representations of each pair. Alignments produced by each approach are fed to a machine learning algorithm. Results show that the monolingual approach results in machine-learning based comparison of person-names in English and Chinese at an accuracy of over 97.0 F-measure.
Extragalactic Globular Clusters and Galaxy Formation

Globular cluster (GC) systems have now been studied in galaxies ranging from dwarfs to giants and spanning the full Hubble sequence of morphological types. Imaging and spectroscopy with the Hubble Space Telescope and large ground-based telescopes have together established that most galaxies have bimodal color distributions that reflect two subpopulations of old GCs: metal-poor and metal-rich. The characteristics of both subpopulations are correlated with those of their parent galaxies. We argue that metal-poor GCs formed in low-mass dark matter halos in the early universe and that their properties reflect biased galaxy assembly. The metal-rich GCs were born in the subsequent dissipational buildup of their parent galaxies and their ages and abundances indicate that most massive early-type galaxies formed the bulk of their stars at early times. Detailed studies of both subpopulations offer some of the strongest constraints on hierarchical galaxy formation that can be obtained in the near-field.
Decarboxylative allylations of ester enolate equivalents

A variety of ester enolate equivalents are generated in situ and undergo α-allylation in high yields via palladium-catalyzed decarboxylative allylation. The transformations are complete within very short reaction times under ambient conditions. Synthesis of α-allylated acyl derivatives provides access to other carboxylic acid and alcohol derivatives via acyl group substitution or reduction.
Doubling the Intensity of an ERL Based Light Source

A light source based on an Energy Recovered Linac (ERL) [1] consists of a superconducting linac and a transfer line that includes wigglers and undulators to produce the synchrotron light. The transfer line brings the electrons bunches back to the beginning of the linac so that their energy can be recovered when they traverse the linac a second time, λ/2 out of phase. There is another interesting condition when the length of the transfer line is (n± 1/4) λ. In this case, the electrons drift through on the zero RF crossing, and make a further pass around the transfer line, effectively doubling the circulating current in the wigglers and undulators. On the third pass through the linac, they will be decelerated and their energy recovered. The longitudinal focusing at the zero crossing is a problem, but it can be canceled if the drifting beam sees a positive energy gradient for the first half of the linac and a negative gradient for the second half (or vice versa). This paper presents a proposal to use a double chicane at the center of the linac to provide this focusing inversion for the drifting beam while leaving the accelerating and decelerating beams on crest.
Synthesis of Protected Benzenepolyselenols

Previously unknown benzenepolyselenols have been synthesized and isolated in their acetyl-protected form. The two molecules 1,3,5-tris(acetylseleno)benzene and 1,2,4,5-tetrakis(acetylseleno)benzene were synthesized by the reductive dealkylation in Na/NH3 of 1,3,5-tris(tert-butylseleno)benzene and 1,2,4,5-tetrakis(tert-butylseleno)benzene, respectively. Hexakis(tert-butylseleno)benzene was also synthesized and structurally characterized by single-crystal X-ray diffraction, but it was not possible to isolate hexakis(acetylseleno)benzene. The synthetic methodology is likely to be useful in the synthesis of other areneselenols.
Assessment of Heat-Damaged Wheat Kernels Using Near-Infrared Spectroscopy

ABSTRACT Heat damage is a serious problem frequently associated with wet harvests because of improper storage of damp grain or artificial drying of moist grain at high temperatures. Heat damage causes protein denaturation and reduces processing quality. The current visual method for assessing heat damage is subjective and based on color change. Denatured protein related to heat damage does not always cause a color change in kernels. The objective of this research was to evaluate the use of nearinfrared (NIR) reflectance spectroscopy to identify heat-damaged wheat kernels. A diode-array NIR spectrometer, which measured reflectance spectra (log (1/R)) from 400 to 1,700 nm, was used to differentiate single kernels of heat-damaged and undamaged wheats. Results showed that light scattering was the major contributor to the spectral characteristics of heat-damaged kernels. For partial least squares (PLS) models, the NIR wavelength region of 750–1,700 nm provided the highest classification accuracy (100%) for bot...
VCSEL electrical packaging analysis and design guidelines for multi-GHz applications

The introduction of the vertical cavity surface emitting laser (VCSEL) diode structure has created the need for enhanced performance, low cost, optical packages capable of supporting data rates as high as 5 Gb/s. The popular laser packages, such as the TO-46 and the TO-56 "cans", which have been traditionally used for edge emitting laser diodes at much lower frequencies, cannot support this dramatic increase in data rates. Package parasitics and severe impedance discontinuities, inherent in the TO-46 and TO-56, impose stringent frequency limitations and dramatically effect the integrity of the electrical signals. Because electrical waveform control is essential for proper laser diode operation, these high frequency performance problems must be identified and overcome. This paper will describe electromagnetic and SPICE modeling techniques which were used to create equivalent circuits of the TO-36 and the TO-56 cans for comparison to measured results to achieve model verification. Subsequently, the models were used to determine frequency limitations associated with the TO-46 and the TO-56 laser cans. Additionally, the specific problems associated with the operation of a VCSEL laser package operating at high frequencies (i.e. >1 Gb/s) were identified; possible solutions for typical driving configurations were then developed. The lessons learned from the analysis of the TO-46 and TO-56 cans were used to determine a rudimentary set of VCSEL package design guidelines. Finally, these guidelines were used to design and model a conceptual VCSEL laser package, dubbed optical package for advanced lasers (OPAL), capable of operation to data rates as high as 5 Gb/s. The modeling techniques used to match the TO-46 and the TO-56 time domain and frequency domain simulations to measurements were extrapolated to create a model of OPAL, and to evaluate it at high frequencies.
A Convenient, General Synthesis of 1,1-Dimethylallyl Esters as Protecting Groups for Carboxylic Acids

Carboxylic acids were converted in high yield to their 1,1-dimethylallyl (DMA) esters in two steps. Palladium-catalyzed deprotection of DMA esters was shown to be compatible with tert-butyl, benzyl, and Fmoc protecting groups, and Fmoc deprotection could be carried out selectively in the presence of DMA esters. DMA esters were also shown to be resistant to nucleophilic attack, suggesting that they will serve as alternatives to tert-butyl esters when acidic deprotection conditions need to be avoided.
Hardware-in-the-Loop Simulation of Robust Gain-Scheduling Control of Port-Fuel-Injection Processes

In this paper, an event-based sampled discrete-time linear system representing a port-fuel-injection process based on wall-wetting dynamics is obtained and formulated as a linear parameter varying (LPV) system. The system parameters used in the engine fuel system model are engine speed, temperature, and load. These system parameters can be measured in real time through physical or virtual sensors. A gain-scheduling controller for the obtained LPV system is then designed based on the numerically efficient convex optimization or linear matrix inequality (LMI) technique. A hardware-in-the-loop (HIL) simulation is performed to validate the gain-scheduling controller on a mixed mean-value and crank-based engine model. The HIL simulation results show the effectiveness of the proposed gain-scheduling controller.
On the least singular value of random symmetric matrices

Let $F_n$ be an $n$ by $n$ symmetric matrix whose entries are bounded by $n^{\gamma}$ for some $\gamma>0$. Consider a randomly perturbed matrix $M_n=F_n+X_n$, where $X_n$ is a {\it random symmetric matrix} whose upper diagonal entries $x_{ij}, 1\le i\le j,$ are iid copies of a random variable $\xi$. Under a very general assumption on $\xi$, we show that for any $B>0$ there exists $A>0$ such that $\mathbb{P}(\sigma_n(M_n)\le n^{-A})\le n^{-B}$.
Precision corrections in the minimal supersymmetric standard model

In this paper we compute one-loop corrections to masses and couplings in the minimal supersymmetric standard model. We present explicit formulae for the complete corrections and a set of compact approximations which hold over the unified parameter space associated with radiative electroweak symmetry breaking. We illustrate the importance of the corrections and the accuracy of our approximations by scanning over the parameter space. We calculate the supersymmetric one-loop corrections to the W-boson mass, the effective weak mixing angle, and the quark and lepton masses, and discuss implications for gauge and Yukawa coupling unification. We also compute the one-loop corrections to the entire superpartner and Higgs-boson mass spectrum. We find significant corrections over much of the parameter space, and illustrate that our approximations are good to O(1%) for many of the superparticle masses.
Low temperature synthesis and characterization of lanthanide-doped BaTiO3 nanocrystals

The vapor diffusion sol–gel (VDSG) method was employed for the room-temperature synthesis of ∼10 nm, aliovalently doped 0.4, 0.8, and 1.6 mol% La:BaTiO3 and 0.4, 0.6, and 1.2 mol% Dy:BaTiO3 nanocrystals. Maximum ensemble relative permittivities of 176 and 208 were observed in the 0.8 mol% La:BaTiO3 and the 1.2 mol% Dy:BaTiO3 nanocrystals, respectively, relative to 89 for undoped BaTiO3 (at 1 MHz, 25 °C) due to local disorder induced by aliovalent substitution.
A bound on the scrambling index of a primitive matrix using Boolean rank

Abstract The scrambling index of an n × n primitive matrix A is the smallest positive integer k such that A k ( A t ) k = J , where A t denotes the transpose of A and J denotes the n × n all ones matrix. For an m × n Boolean matrix M , its Boolean rank b ( M ) is the smallest positive integer b such that M = AB for some m × b Boolean matrix A and b × n Boolean matrix B . In this paper, we give an upper bound on the scrambling index of an n × n primitive matrix M in terms of its Boolean rank b ( M ) . Furthermore we characterize all primitive matrices that achieve the upper bound.