cssi/SciSciGPT-SciSciNet huggingface dataset:
A Small-Sample Estimator for the Sample-Selection Model

A semiparametric estimator for evaluating the parameters of data generated under a sample selection process is developed. This estimator is based on the generalized maximum entropy estimator and performs well for small and ill-posed samples. Theoretical and sampling comparisons with parametric and semiparametric estimators are given. This method and standard ones are applied to three small-sample empirical applications of the wage-participation model for female teenage heads of households, immigrants, and Native Americans.
GROWTH AND FOREIGN DIRECT INVESTMENT IN AMERICAN STATES, 1977–2001

Foreign Direct Investment in the United States is analyzed using a stochastic production function with FDI as an input. Low but significant technical inefficiency is found across American states similar to earlier studies but now with FDI explicitly accounted for. FDI is found to have a low but significant impact on regional economic growth. Supporting the literature, little evidence is found for human capital causing more FDI or GSP growth at the regional level.
EXPLORING FIFTH FORCE INTERACTIONS WITH 18TH CENTURY TECHNOLOGY

Many theories which unify gravity with the other known forces of nature predict the existence of an intermediate-range "fifth force" similar to gravity. Such a force could be manifest as a deviation from the gravitational inverse-square law. Currently, at distances near 10-1 m, the inverse-square law is known to be correct to about one part per thousand. I present the design of an experiment that will improve this limit by two orders of magnitude. This is accomplished by constructing a torsion pendulum and source mass apparatus that are particularly insensitive to Newtonian gravity and, simultaneously, maximally sensitive to violations of the same.
Oxidative free-radical cyclization of dimethyl (4E,8-nonadien-1-yl)malonate and ethyl (4E,8-nonadien-1-yl)cyanoacetate

Abstract Oxidative free-radical cyclization of 11a or 11b in the presence of Mn(III) and Cu(II) leads to the expected dienylcyclopentane 14 by rapid oxidation of the kinetically formed cyclopentanealkyl radical 13. Oxidative cyclization of 11a with Mn(III) only in ethanol or with benzoyl peroxide in cyclohexane affords a mixture of the stereoisomers of methylhydrindane 15. As expected, the first cyclization of the stabilized acyclic radical 12 is reversible. The second cyclization of the unstabilized cyclohexyl radical 17 leads to the hydrindanemethyl radical 16.
Adaptive PI Control of STATCOM for Voltage Regulation

STATCOM can provide fast and efficient reactive power support to maintain power system voltage stability. In the literature, various STATCOM control methods have been discussed including many applications of proportional-integral (PI) controllers. However, these previous works obtain the PI gains via a trial-and-error approach or extensive studies with a tradeoff of performance and applicability. Hence, control parameters for the optimal performance at a given operating point may not be effective at a different operating point. This paper proposes a new control model based on adaptive PI control, which can self-adjust the control gains during a disturbance such that the performance always matches a desired response, regardless of the change of operating condition. Since the adjustment is autonomous, this gives the plug-and-play capability for STATCOM operation. In the simulation test, the adaptive PI control shows consistent excellence under various operating conditions, such as different initial control gains, different load levels, change of transmission network, consecutive disturbances, and a severe disturbance. In contrast, the conventional STATCOM control with tuned, fixed PI gains usually perform fine in the original system, but may not perform as efficient as the proposed control method when there is a change of system conditions.
Tearing-mode stability of tokamak plasmas with elliptical cross-section

The effect of the ellipticity of the plasma cross-section on tearing-mode stability is investigated. The induced coupling between modes is shown to be de-stabilizing. The modification of the equilibrium tends, howeyer, to stabilize the tearing modes. The net effect depends on the manner in which the equilibrium is modified as the plasma cross-section shape is changed.
Solving matrix models using holomorphy

We investigate the relationship between supersymmetric gauge theories with moduli spaces and matrix models. Particular attention is given to situations where the moduli space gets quantum corrected. These corrections are controlled by holomorphy. It is argued that these quantum deformations give rise to non-trivial relations for generalized resolvents that must hold in the associated matrix model. These relations allow to solve a sector of the associated matrix model in a similar way to a one-matrix model, by studying a curve that encodes the generalized resolvents. At the level of loop equations for the matrix model, the situations with a moduli space can sometimes be considered as a degeneration of an infinite set of linear equations, and the quantum moduli space encodes the consistency conditions for these equations to have a solution.
Effects of massive gluons on quarkonia in light-front QCD

A constituent parton picture of hadrons with logarithmic confinement arises naturally in light-front QCD when the hamiltonian is computed using a perturbative renormalization group; however, rotational symmetry is not manifest as a simple kinematic symmetry. Relevant operators must typically be fine-tuned when a perturbative renormalization group is used, and in light-front field theory such operators contain functions of longitudinal momenta. We explore the possibility that a gluon mass operator with simple longitudinal momentum dependence may improve approximate kinematic rotational symmetry, as revealed by the potential between heavy quarks.
Mott insulators in strong electric fields

Recent experiments on ultracold atomic gases in an optical lattice potential have produced a Mott insulating state of ${}^{87}\mathrm{Rb}$ atoms. This state is stable to a small applied potential gradient (an ``electric'' field), but a resonant response was observed when the potential energy drop per lattice spacing $(E),$ was close to the repulsive interaction energy (U) between two atoms in the same lattice potential well. We identify all states which are resonantly coupled to the Mott insulator for $E\ensuremath{\approx}U$ via an infinitesimal tunneling amplitude between neighboring potential wells. The strong correlation between these states is described by an effective Hamiltonian for the resonant subspace. This Hamiltonian exhibits quantum phase transitions associated with an Ising density wave order and with the appearance of superfluidity in the directions transverse to the electric field. We suggest that the observed resonant response is related to these transitions and propose experiments to directly detect the order parameters. The generalizations to electric fields applied in different directions and to a variety of lattices should allow study of numerous other correlated quantum phases.
Reliable video over software-defined networking (RVSDN)

Ensuring end-to-end quality of service for video applications requires the network to choose the most feasible path in terms of bandwidth, delay and jitter. Quality of service can only be ensured if the paths are reliable — perform to specification per request. This paper makes four contributions to research. First, it presents Reliable Video over Software-Defined Networking (RVSDN) which builds upon previous work of Video over Software-Defined Networking (VSDN) to address the issue of finding the most reliable path(s) through the network for video applications. Second, it presents the design and implementation of RVSDN. Third, it presents the experience of integrating RVSDN into ns-3 which is a network simulator used by the research community to simulate and model computer networks. Finally, it presents the results of RVSDN in terms of the number of requests serviced by the network architecture. RVSDN is able to service 31 times more requests than VSDN and MPLS explicit routing when the reliability constraint is 0.995 or greater using aggregation of reliability across network paths.
Electrical impedance string probes for two-phase void and velocity measurements

Abstract An instrumentation system was developed to measure two-phase flow velocity and void fraction. The principle of operation of this system was based on the measurement of the electrical impedance of two-phase mixtures. Two-phase velocity is estimated by time-of-flight analysis of signals from two spatially separated sensors. A technique involving measurement of both the capacitance and the conductance of the mixture was used to determine void fraction and correct for the effect of liquid distribution. The string probe instrumentation proved to be durable in air/water and steam/water flows and demonstrated an ability to measure a wide range of flow velocities (1–17 m/s) and void fractions (0.25−0.99+).
Particle Mixing and Volumetric Expansion in a Vibrated Granular Bed

The present experiments are an investigation of the expansion and mixing that occur in a horizontal bed of particles subjected to vibrational accelerations in the direction parallel to gravity. The particles are colored-glass balls of uniform size; three different bed heights are examined of 6, 9, and 12 particle diameters. The vibrational frequency and amplitude are controlled separately to cover a range of acceleration levels from 1 to 5.5 times gravitational acceleration. The expansion results show that above a critical frequency, the bed begins to expand and the bed solid fraction decreases. This result is independent of the vibrational amplitude. Above a second critical frequency, the thickest beds show a further decrease in solid fraction; the minimum value of solid fraction for all bed heights is approximately 0.21 ± 0.03. The mixing results indicate that the mixing times decrease significantly with the expansion of the bed. However, the mixing times are greater as the bed depth increases. Unlike the expansion results, the mixing times depend on the amplitude of the vibration. A simple analysis of the flow is performed using a self-diffusion coefficient developed from dense-gas kinetic theory. The analysis qualitatively agrees with the experiments for the largest vibrational velocities and for the thinnest beds.
Skeletonization of gray-scale images by gray weighted distance transform

In pattern recognition, thinning algorithms are often a useful tool to represent a digital pattern by means of a skeletonized image, consisting of a set of one-pixel-width lines that highlight the significant features interest in applying thinning directly to gray-scale images, motivated by the desire of processing images characterized by meaningful information distributed over different levels of gray intensity. In this paper, a new algorithm is presented which can skeletonize both black-white and gray pictures. This algorithm is based on the gray distance transformation and can be used to process any non-well uniformly distributed gray-scale picture and can preserve the topology of original picture. This process includes a preliminary phase of investigation in the 'hollows' in the gray-scale image; these hollows are considered not as topological constrains for the skeleton structure depending on their statistically significant depth. This algorithm can also be executed on a parallel machine as all the operations are executed in local. Some examples are discussed to illustrate the algorithm.
Analysis of a large structure/biological activity data set using recursive partitioning.

Combinatorial chemistry and high-throughput screening are revolutionizing the process of lead discovery in the pharmaceutical industry. Large numbers of structures and vast quantities of biological assay data are quickly being accumulated, overwhelming traditional structure/activity relationship (SAR) analysis technologies. Recursive partitioning is a method for statistically determining rules that classify objects into similar categories or, in this case, structures into groups of molecules with similar potencies. SCAM is a computer program implemented to make extremely efficient use of this methodology. Depending on the size of the data set, rules explaining biological data can be determined interactively. An example data set of 1650 monoamine oxidase inhibitors exemplifies the method, yielding substructural rules and leading to general classifications of these inhibitors. The method scales linearly with the number of descriptors, so hundreds of thousands of structures can be analyzed utilizing thousand...
Surface charge compensation for a highly charged ion emission microscope

A surface charge compensation electron flood gun has been added to the Lawrence Livermore National Laboratory (LLNL) highly charged ion (HCI) emission microscope. HCI surface interaction results in a significant charge residue being left on the surface of insulators and semiconductors. This residual charge causes undesirable aberrations in the microscope images and a reduction of the time-of-flight (T-O-F) mass resolution when studying the surfaces of insulators and semiconductors. The benefits and problems associated with HCI microscopy and recent results of the electron flood gun-enhanced HCI microscope are discussed.
Automorphisms mapping a point into a subvariety

The problem of deciding, given a complex variety X, a point x ∈ X, and a subvariety Z ⊆ X, whether there is an automorphism of X mapping x into Z is proved undecidable. Along the way, we prove the undecidability of a version of Hilbert’s tenth problem for systems of polynomials over Z defining an affine Q-variety whose projective closure is smooth.
A benzannulation strategy for the synthesis of phenols and heteroaromatic compounds based on the reaction of (trialkylsilyl)vinylketenes with lithium ynolates.

Abstract (Trialkylsilyl)vinylketenes react with lithium ynolates to generate 3-(oxido)dienylketenes, which undergo rapid 6π-electrocyclization. The ultimate products of this benzannulation are highly substituted resorcinol monosilyl ethers, which are formed via a [1,3] carbon to oxygen silyl group shift. Further transformations of the benzannulation products are described providing efficient access to ortho-benzoquinones and benzofuran, benzoxepine, and benzoxocine ring systems.
Spectrally shaped generalized multitone direct sequence spread spectrum

In this paper, a new modulation scheme that is called spectrally shaped generalized multitone direct sequence spread spectrum (SSG-MT-DS-SS) is proposed. This scheme enables moderate shaping of the transmitted spectrum without the use of spectral-shaping filters; instead, the spectrum is shaped by appropriate selection of the parameters of each subcarrier. These parameters are amplitude, data rate, processing gain, and the frequency separation between adjacent subcarriers. Since these parameters are selectable, this scheme is a completely generalized MT-DS-SS approach. Analysis and simulation results show that by properly choosing these parameters, the level of the spectral sidelobes can be reduced, while slightly changing the width of the mainlobe and simultaneously obtaining a good error-probability performance, on both additive white Gaussian noise and dispersive fading channels. For even a small number of subcarriers (e.g., 3-5), spectral sidelobes can be reduced by 3-6 dB from those of the conventional MT-DS-SS spectrum, with little or no degradation in error-probability performance. For larger numbers of subcarriers, additional sidelobe reductions are attainable. In addition, the SSG-MT-DS-SS system has a smaller peak-to-average power ratio than the conventional MT-DS-SS when the amplitudes of each subcarrier are not identical
SECULAR EVOLUTION OF HD 12661: A SYSTEM CAUGHT AT AN UNLIKELY TIME

The eccentricity evolution of multiple planet systems can provide valuable constraints on planet formation models. Unfortunately, the inevitable uncertainties in the current orbital elements can lead to significant ambiguities in the nature of the secular evolution. Integrating any single set of orbital elements inadequately describes the full range of secular evolutions consistent with current observations. Thus, we combine radial velocity observations of HD 12661 with Markov Chain Monte Carlo sampling to generate ensembles of initial conditions for direct n-body integrations. We find that any mean motion resonances are quite weak and do not significantly impact the secular evolution, and that current observations indicate circulation or large-amplitude libration of the periapses. The eccentricity of the outer planet undergoes large oscillations for nearly all of the allowed two-planet orbital solutions. This type of secular evolution would arise if planet c had been impulsively perturbed, perhaps due to strong scattering of an additional planet that was subsequently accreted onto the star. Finally, we note that the secular evolution implied by the current orbital configuration implies that planet c spends ~ 96% of the time following an orbit more eccentric than that presently observed. Either this system is being observed during a relatively rare state, or additional planets are affecting the observed radial velocities and/or the system's secular eccentricity evolution.
Synthesis and characterization of novel trifluoromethyl-containing alcohols with Ruppert's reagent

Abstract Synthesis and characterization of novel new trifluoromethyl-containing alcohols using Ruppert's reagent [(trimethyl)trifluoromethylsilane] ( 1 ) are reported. The reactions of 1 with various ketones and aldehydes, such as tetraphenylcyclopentadienone ( 2a ), 9,10-anthraquinone ( 2b ), pyrenaldehyde ( 2c ), 2,6-dimethyl-para-anisaldehyde ( 2d ), and 2,3(methylenedioxy)benzaldehyde ( 2e ) in the presence of a catalytic amount of tetrabutylammonium fluoride in THF led to the formation of the corresponding trifluoromethylated silyl ether derivatives 3a – e in almost quantitative yields. Acid hydrolysis of 3a – e gave the desired trifluoromethylated alcohol derivatives ( 4a – e ) in excellent isolated yields. Compounds were characterized by IR, NMR ( 1 H, 19 F, 13 C NMR), GCMS, and elemental analysis. Single crystal X-ray structures of 4a and 4b support the proposed products.
Corporate Control, Portfolio Choice, and the Decline of Banking

In the 1980s, U.S. banks became systematically less profitable and riskier as nonbank competition eroded the profitability of banks' traditional activities. Bank failures rose exponentially during this decade. The leading explanation for the persistence of these trends centers on fixed-rate deposit insurance: the insurance gives bank equityholders an incentive to take on risk when the value of bank charters falls. We propose and test an alternative explanation based on corporate control considerations. We show that managerial entrenchment played a more important role than did the moral hazard associated with deposit insurance in explaining the recent behavior of the banking industry. THE 1980s WAS NOT a good decade for U.S. banks. Gerald Corrigan (1992), the head of the New York Federal Reserve Bank during the period, observed that: .. . we would all accept the fact that the decade of the 1980s was surely the most difficult interval faced by the U.S. banking system since the 1930s." Indeed, during the 1980s, bank profitability declined steadily, whether measured by accounting return on equity, return on assets, or market value. Figure 1 shows the accounting return on assets.' Not only did banking become less profitable, it became riskier. The ratio of charge-offs to total loans, a measure of risk, rose almost monotonically in the last decade. (See Figure 1.)
Missile propulsion cost modeling

Abstract An approach for parametric propulsion system cost modeling is presented and is illustrated by Cost Estimating Relationships (CERs) for unit production costs of solid propellant booster stages. Due to their relative simplicity, the costs obtained from the CERs represent only first order approximations of booster stage costs. They were developed from cost and technical data of historical propulsion systems available in the open literature. The approach for developing the CERs is outlined and the rationale for the selection of independent parameters is presented. The analysis of the cost data revealed several generic observations and “rules of thumb”. These are given in this paper, since they might prove useful for “back of the envelope” type cost predictions.
New Neighbors from 2MASS: Activity and Kinematics at the Bottom of the Main Sequence

We have combined 2MASS and POSS II data in a search for nearby ultracool (later than M6.5) dwarfs with Ks 6 A) ultracool M dwarfs are consistent with an ordinary old disk stellar population, while the kinematics of inactive ultracool M dwarfs are more typical of a 0.5 Gyr old population. The early L dwarfs in the sample have kinematics consistent with old ages, suggesting that the hydrogen-burning limit is near spectral types L2–L4. We use the available data on M and L dwarfs to show that chromospheric activity drops with decreasing mass and temperature and that at a given (M8 or later) spectral type, the younger field (brown) dwarfs are less active than many of the older, more massive field stellar dwarfs. Thus, contrary to the well-known stellar age-activity relationship, low activity in field ultracool dwarfs can be an indication of comparative youth and substellar mass.
Conical Flow induced by Quenched QCD Jets

We suggest that the energy/momentum loss by quenched QCD jets created in heavy ion collisions at RHIC propagates as a collective excitation or “conical flow” of the produced matter. We solve the linearized relativistic hydrodynamic equations to detail the flow picture. We argue that for RHIC collisions the direction of this flow should form a cone at a specific large angle with the jet of about 70°, and thus lead to peaks in particle correlations at the angle Δ ϕ = π ± 1.2 rad relative to the large-pt trigger.
Error simulation of paired-comparison-based scaling methods

Subjective image quality measurement usually resorts to psycho physical scaling. However, it is difficult to evaluate the inherent precision of these scaling methods. Without knowing the potential errors of the measurement, subsequent use of the data can be misleading. In this paper, the errors on scaled values derived form paired comparison based scaling methods are simulated with randomly introduced proportion of choice errors that follow the binomial distribution. Simulation results are given for various combinations of the number of stimuli and the sampling size. The errors are presented in the form of average standard deviation of the scaled values and can be fitted reasonably well with an empirical equation that can be sued for scaling error estimation and measurement design. The simulation proves paired comparison based scaling methods can have large errors on the derived scaled values when the sampling size and the number of stimuli are small. Examples are also given to show the potential errors on actually scaled values of color image prints as measured by the method of paired comparison.
Combined C-H functionalization/C-N bond formation route to carbazoles.

A new method in which a series of substituted carbazoles is efficiently produced by the combination of an amide and an arene is described. The key feature of this method is the palladium-catalyzed tandem directed C−H functionalization and amide arylation. The method tolerates substitution on either ring of the biaryl amide substrates, and the products can be assembled in a simple two-step protocol from readily available reagents. The Pd(0) species generated are reoxidized to Pd(II) in the presence of Cu(OAc)2 and an atmosphere of oxygen.
Averaged modeling and analysis of multilevel converters

Multilevel voltage-source converters (VSC) are attractive for high-voltage and high-power applications. However, the increased part counts and control complexity also complicate the converter modeling and control. One particular control problem is the balancing of dc capacitor voltages. Conventional voltage balancing control design has been based on periodic steady-state or line-cycle averaged models of the converter that don't correctly predict the capacitor voltage dynamics within a line cycle and under dynamic conditions. This paper develops an averaged model for three-level neutral-point clamped (NPC) converters that is valid under all conditions and involves switching-cycle averaging only. Unlike previous works, no assumption is made about the balance of ac line voltages, making the resulting model suitable for analysis and simulation of large, possibly unbalanced electric power systems. Applications of the model include more efficient system simulation, controller analysis and design for ac current regulation, dc bus voltage regulation and dc capacitor voltage balancing. Simulation results are presented to validate the proposed models.
Advertising and information costs: an empirical study

As pointed out previously by economists, the implicit demand for cost‐saving information by potential buyers generates a derived demand for advertising by sellers. This study adds to the body of evidence that reveals the positive role of advertising in the market process. The evidence presented here suggests that sellers do respond to the higher time costs faced by transient populations by providing advertising qua information in a manner that minimizes the total cost of voluntary exchange.
Visible-light photoredox catalysis: aza-Henry reactions via C-H functionalization.

We report the application of visible-light photoredox catalysis for the formation of C−C bonds between tertiary N-arylamines and nitroalkanes via an oxidative aza-Henry reaction. In the presence of 1 mol % Ir(ppy)2(dtbbpy)PF6, efficient coupling of nitroalkanes with in situ-generated iminium ions provides the desired products in up to 96% yield. Mechanistic studies suggest that reductive quenching of the Ir3+ excited state by the tertiary amine leads to the ammonium radical cation, with subsequent catalyst turnover (Ir2+ → Ir3+) likely effected by atmospheric oxygen.
Chemoenzymatic studies: From cycloheptatriene to the core of zaragozic acids

Abstract (1 R ,4 S ,6 S )-4-Acetoxy-6-triisopropylsilyloxy-2-cyclohepten-1-ol, prepared from cycloheptatriene utilizing an asymmetrization of the precursor diol with Candida antarctica lipase B/isopropenyl acetate, was converted to (1 S ,3 R ,4 S ,5 S ,6 R ,7 R )-4,6,7-triacetoxy-5-benzyloxymethyl-4-acetoxymethyl-2,8-dioxabicyclo[3.2.1]octane representing the core of zaragozic acid by a strategy involving Rubottom oxidations and ozonolysis.
MaxBCG: A red-sequence galaxy cluster finder

Measurements of galaxy cluster abundances, clustering properties, and mass-to-light ratios in current and future surveys can provide important cosmological constraints. Digital wide-field imaging surveys, the recently demonstrated fidelity of red-sequence cluster detection techniques, and a new generation of realistic mock galaxy surveys provide the means for construction of large, cosmologically interesting cluster samples, whose selection and properties can be understood in unprecedented depth. Here we present the details of the "maxBCG" algorithm, a cluster detection technique tailored to multiband CCD imaging data. MaxBCG primarily relies on an observational cornerstone of massive galaxy clusters: they are marked by an overdensity of bright, uniformly red galaxies. This detection scheme also exploits classical brightest cluster galaxies (BCGs), which are often found at the centers of these same massive clusters. We study the algorithm through its performance on large, realistic, mock galaxy catalogs, which reveal that it is over 90% pure for clusters at 0.1 < z < 0.3 with 10 or more red galaxies, and over 90% complete for halos at 0.1 < z < 0.3 with masses above 2 × 1014 h-1 M☉. MaxBCG is able to approximately recover the underlying halo abundance function and assign cluster richnesses strongly coupled to the underlying halo properties. The same tests indicate that maxBCG rarely fragments halos, occasionally overmerges line-of-sight neighboring (10 h-1 Mpc) halos, and overestimates the intrinsic halo red-sequence galaxy population by no more than 20%. The study concludes with a discussion of considerations for cosmological measurements with such catalogs, including modeling the selection function, the role of photometric errors, the possible cosmological dependence of richness measurements, and fair cluster selection across broad redshift ranges employing multiple bandpasses.
Information pooling through majority-rule voting: Condorcet's jury theorem with correlated votes

Abstract Does majority-rule voting steer an imperfectly informed assembly of people towards the full-information outcome? Condorcet's jury theorem provides an affirmative answer under certain conditions. A key condition is that the votes be statistically independent; however, it is unrealistic, and hence, unacceptable. This paper generalizes the jury theorem to certain general models of correlated voting, viz., normal, hypergeometric and Polya distributions. The paper proves that the effectiveness of majority-rule voting decreases as the correlation between votes increases. Potential applications are indicated.
Dualities of the matrix model from T-duality of the Type II String

Abstract We investigate in the Matrix theory framework, the subgroup of dualities of the DLCQ of M-theory compactified on three-tori, which corresponds to T -duality in the auxiliary Type II string theory. We show how these dualities are realized in the supersymmetric Yang-Mills gauge theories on dual non-commutative three-tori.
A Conserved Helicase Processivity Factor Is Needed for Conjugation and Replication of an Integrative and Conjugative Element

Integrative and conjugative elements (ICEs) are agents of horizontal gene transfer and have major roles in evolution and acquisition of new traits, including antibiotic resistances. ICEs are found integrated in a host chromosome and can excise and transfer to recipient bacteria via conjugation. Conjugation involves nicking of the ICE origin of transfer (oriT) by the ICE–encoded relaxase and transfer of the nicked single strand of ICE DNA. For ICEBs1 of Bacillus subtilis, nicking of oriT by the ICEBs1 relaxase NicK also initiates rolling circle replication. This autonomous replication of ICEBs1 is critical for stability of the excised element in growing cells. We found a conserved and previously uncharacterized ICE gene that is required for conjugation and replication of ICEBs1. Our results indicate that this gene, helP (formerly ydcP), encodes a helicase processivity factor that enables the host-encoded helicase PcrA to unwind the double-stranded ICEBs1 DNA. HelP was required for both conjugation and replication of ICEBs1, and HelP and NicK were the only ICEBs1 proteins needed for replication from ICEBs1 oriT. Using chromatin immunoprecipitation, we measured association of HelP, NicK, PcrA, and the host-encoded single-strand DNA binding protein Ssb with ICEBs1. We found that NicK was required for association of HelP and PcrA with ICEBs1 DNA. HelP was required for association of PcrA and Ssb with ICEBs1 regions distal, but not proximal, to oriT, indicating that PcrA needs HelP to progress beyond nicked oriT and unwind ICEBs1. In vitro, HelP directly stimulated the helicase activity of the PcrA homologue UvrD. Our findings demonstrate that HelP is a helicase processivity factor needed for efficient unwinding of ICEBs1 for conjugation and replication. Homologues of HelP and PcrA-type helicases are encoded on many known and putative ICEs. We propose that these factors are essential for ICE conjugation, replication, and genetic stability.
Ytterbium Trichloride-Catalyzed Diels-Alder Reactions of Unactivated Dienes

Abstract Ytterbium chloride (YbCl3) is an effective and reusable catalyst for Diels-Alder reactions of unactivated dienes with α,β-unsaturated ketones and aldehydes at room temperature, leading to products with high regio- and stereoselectivities.
CONGENITAL ADRENAL HYPERPLASIA

Congenital adrenal hyperplasia (CAH) is a family of genetic disorders from a deleterious mutation in a gene encoding adrenal steroidogenic enzyme essential for cortisol biosynthesis. Recent molecular advances have provided the genetic basis for the phenotypic variability in CAH, a means for accurately genotyping family members of CAH patients including prenatal prediction of the genotype in fetuses at risk of the disorder, and have helped to better define the hormonal criteria for the varying spectrum of CAH disorders. Biochemical advances have simultaneously aided the diagnosis and therapeutic monitoring of CAH patients. Prenatal maternal dexamethasone therapy for fetal CAH prevents or minimizes virilizing sequelae in the majority of prenatally treated affected females, but was associated with significant maternal side effects. Newborn screening for CAH has contributed to the prevention of morbidity of delayed diagnosis of CAH in more than two thirds of affected neonates. Current treatment methods, however, may not be optimal for achieving normal genetic height and appropriate weight in CAH patients, and more effective approaches to CAH therapy remain to be explored.
A Photo Touch on Amines: New Synthetic Adventures of Nitrogen Radical Cations

Amines have been used as sacrificial electron donors to reduce photoexcited Ru(II) or Ir(III) complexes, during which they are oxidized to nitrogen radical cations. Recently, the synthetic potential of these nitrogen radical cations have caught synthetic organic chemists’ attention. They have been exploited in various transformations yielding a number of elegant methods for amine synthesis. This article highlights recent developments on nitrogen radical cation chemistry under visible-light photocatalysis.
Schmooze or lose: Social friction and lubrication in e-mail negotiations.

We explored how the process of e-mail negotiation differs from face-to-face negotiation and then tested hypotheses about how its liabilities can be minimized. In the first experiment, participants negotiated one-on-one, either face-to-face or via e-mail. Consistent with expectations, negotiators took advantage of e-mail by exchanging more complex, multiple-issue offers than they exchanged face-to-face. Yet, e-mail reduced rapport-building conversation about non-negotiable, contextual issues, and clarifying questions which prevent misunderstandings and facilitate rapport. E-mail negotiators compensated with more explicit statements about the relationship, but these were less effective in preventing mistrust and misunderstanding. In a second experiment, we tested the power of a minimal intervention designed to reduce the liabilities of e-mail. Half the negotiation dyads had a personalized telephone conversation ("schmoozed") before engaging in e-mail negotiations, and the other half did not schmooze. Even though the telephone conversation was strictly non-business, schmoozing negotiators anticipated and planned a cooperative, positive negotiation experience from the outset, and they attained better economic and social outcomes. This was primarily true among mixed-gender dyads.
CHASING THE GZK WITH HiRes

The HiRes collaboration has recently announced preliminary measurements of the energy spectrum of ultra-high energy cosmic rays (UHECR), as seen in monocular analyses from each of the two HiRes sites. This spectrum is consistent with the existence of the GZK cutoff, as well other aspects of the energy loss processes that cause the GZK cutoff. Based on the analytic energy loss formalism of Berezinsky et al., the HiRes spectra favor a distribution of extragalactic sources that has a similar distribution to that of luminous matter in the universe, both in its local over-density and in its cosmological evolution.
Prison gangs, norms, and organizations

Abstract Much of the order that exists in the inmate social system is not the result of government action. How do prisoners create order? Inmates use a combination of norms and organizations to provide governance privately. Norms rely on decentralized information transmission and enforcement mechanisms. Organizations, on the other hand, have well-defined memberships and create explicit information transmission and enforcement mechanisms. Inmates cannot rely on norms for governance when the inmate population is large, increasingly crowded, and when fewer inmates arrive with a prior prison commitment. When norms fail, inmates create organizations to protect themselves and provide governance. Once these groups have the power to deter predators, they prey on others. Contemporary and historical evidence from California correctional facilities provide support for these claims and suggest an explanation of the origin and growth of prison gangs.
A pocket model for aluminum agglomeration in composite propellants

This paper presents a model for the purpose of estimating the fraction of aluminum powder that will form agglomerates at the surface of deflagrating composite propellants. The basic idea is that the fraction agglomerated depends upon the amount of aluminum that melts within effective binder pocket volumes framed by oxidizer particles. The effective pocket depends upon the ability of ammonium perchlorate modals to encapsulate the aluminum and provide a local temperature sufficient to ignite the aluminum. Model results are discussed in the light of data showing effects of propellant formulation variables and pressure.
Nucleoside Conjugates V: Synthesis and Biological Activity of 9-(β-D-Arabinofuranosyl)adenine Conjugates of Corticosteroids

Eight 5′-(steroid-21-phosphoryl)-9-(β-D-arabinofuranosyl)-adenines (IV-XI) have been prepared and evaluated against L1210 lymphoid leukemia in culture. These include the 9-(β-D-arabinofuranosyl)adenine conjugates of hydrocortisone (IV), cortisone (V), corticosterone (VI), cortexolone (VII), 11-deoxycorticosterone (VIII), prednisolone (IX), prednisone (X), and dexamethasone (XI). Conjugates IV, IX, X, and XI inhibited the in vitro growth of L1210 lymphoid leukemia cells by 50% (ED50) at a concentration of 2.3-7.8 μM, while 9-(β-D-arabinofuranosyl)adenine (vidarabine, I) and its 5′-monophosphate (II) each showed ED50 value of 30 μM. All of the conjugates were enzymatically hydrolyzed to the corresponding steroid and II, the latter undergoing further hydrolysis to I, by phosphodiesterase I, 5′-nucleotidase, and acid phosphatase. However, these congugates were resistant to hydrolysis by alkaline phosphatase and adenosine deaminase.
Does SNAP Improve Your Health

Abstract In this study, we examine the effect of SNAP on health quite generally, examining self-assessed health (SAH), healthy time, and basic health utilization measures as outcomes. Our approach is to model outcomes and participation simultaneously, using exogenous variation in state eligibility to identify SNAP participation. We use this approach for both ordered choices (health) and count outcomes (sickdays, office-based visits, outpatient visits), where the former uses maximum likelihood and the latter maximum simulated likelihood. In addition, we control for state-level unobservables that are correlated with both participation and health, which previous studies of this question have neglected. Our results indicate that SNAP has an consistently positive effect on SAH; it significantly increases the probability of reporting excellent or very good health. We also find that SNAP participants spend about 3 fewer days in bed due to illness each year, and report between 1 and 2 fewer office-based doctor visits and a fraction fewer outpatient visits. Supplementary specifications indicate that, although SNAP participants consume fewer office visits overall, they have more checkups than comparable non-participants.
Wettability Alteration Caused by Oil-Based Muds and Mud Components

Wettability alteration caused by oil-based muds and mud filtrates is of great concern in coring operations. This paper shows that mud filtrates from whole muds can change the wettability of water-wet cores significantly. Individual components primarily responsible for this wettability alteration are identified.
V1647 Orionis: Optical Photometric and Spectroscopic Monitoring Through the 2003-2006 Outburst

We present results from an optical imaging and spectroscopic monitoring campaign on the young, low-mass eruptive variable star V1647 Orionis. The star and associated nebulosity (McNeil's Nebula) were observed over the period 2004 February to 2006 February with observations commencing a few months after the original outburst event occurred. Using the Gemini North telescope, we obtained multiband optical imaging photometry and medium-resolution long-slit spectroscopy of V1647 Ori on an approximately monthly interval. During this period, V1647 Ori remained at, or close to, peak brightness and then faded by 5 mag to close to its pre-outburst brightness. This implies an outburst timescale of around 27 months. Spectral features seen in both emission and absorption varied considerably during the monitoring period. For example, the H{alpha} line changed significantly in both intensity and profile. We present and discuss the observed photometric and spectroscopic changes and consider how this eruptive event relates to the early formative stages of low-mass stars.
Uniform estimates on multi-linear operators with modulation symmetry

In a previous paper [20] in this series, we gaveLp estimates for multi-linear operators given by multipliers which are singular on a non-degenerate subspace of some dimensionk. In this paper, we give uniform estimates when the subspace approaches a degenerate region in the casek = 1, and when all the exponentsp are between 2 and ∞. In particular, we recover the non-endpoint uniform estimates for the bilinear Hubert transform in [12].
Wing Section Optimization for Supersonic Viscous Flow

To improve the performance of a highly swept supersonic wing, it is desirable to have an automated design method that also includes a higher fidelity to the flow physics. With this impetus, an aerodynamic optimization methodology incorporating the thin-layer Navier-Stokes equations and sensitivity analysis had previously been developed. Prior to embarking upon the full wing design task, the present investigation concentrated on the identification of effective optimization problem formulations and testing the feasibility of the employed methodology, by defining two-dimensional test cases. Starting with two distinctly different initial airfoils, two independent optimizations resulted in shapes with similar features: cambered, parabolic profiles with sharp leading- and trailing-edges. Secondly, an outboard wing section normal to the subsonic portion of the leading edge, which had a high normal angle-of attack, was considered. The optimization resulted in a shape with twist and camber that eliminated the adverse pressure gradient, hence, exploiting the leading-edge thrust. The wing section shapes obtained in all the test cases included the features predicted by previous studies
Low-lying zeros of number field L-functions

Abstract Text One of the most important statistics in studying the zeros of L-functions is the 1-level density, which measures the concentration of zeros near the central point. Fouvry and Iwaniec (2003) [FI] proved that the 1-level density for L-functions attached to imaginary quadratic fields agrees with results predicted by random matrix theory. In this paper, we show a similar agreement with random matrix theory occurring in more general sequences of number fields. We first show that the main term agrees with random matrix theory, and similar to all other families studied to date, is independent of the arithmetic of the fields. We then derive the first lower order term of the 1-level density, and see the arithmetic enter. Video For a video summary of this paper, please click here or visit http://www.youtube.com/watch?v=zpb-gu3G8i0 .
Multiresolution analysis in statistical mechanics. II. The wavelet transform as a basis for Monte Carlo simulations on lattices

In this paper, we extend our analysis of lattice systems using the wavelet transform to systems for which exact enumeration is impractical. For such systems, we illustrate a wavelet-accelerated Monte Carlo (WAMC) algorithm, which hierarchically coarse-grains a lattice model by computing the probability distribution for successively larger block spins. We demonstrate that although the method perturbs the system by changing its Hamiltonian and by allowing block spins to take on values not permitted for individual spins, the results obtained agree with the analytical results in the preceding paper, and “converge” to exact results obtained in the absence of coarse-graining. Additionally, we show that the decorrelation time for the WAMC is no worse than that of Metropolis Monte Carlo (MMC), and that scaling laws can be constructed from data performed in several short simulations to estimate the results that would be obtained from the original simulation. Although the algorithm is not asymptotically faster than traditional MMC, the new algorithm executes several orders of magnitude faster than a full simulation of the original problem because of its hierarchical design. Consequently, the new method allows for rapid analysis of a phase diagram, allowing computational time to be focused on regions near phase transitions.
Beyond the Standard Model Searches at the Lhc

The SM is an extremely successful gauge theory based on the symmetry group SU(3)c 8 SU(2) , 8 U ( 1 ) y . Local gauge invariance requires the existence of vector bosons mediating the strong and electroweak forces: the gluons, photon, W and Z bosons. Many extensions of the SM predict the existence of additional gauge bosons resulting from enlarged symmetry groups. For example, E6based theories predict the existence of additional U ( 1) groups originating from the breaking of J ! & into subgroups, eventually breaking down to the SM group at low energy. New heavy gauge bosons are generically refered to as W' and 2' bosons. These are also predicted in theories with extra dimensions in the form of Kaluza-Klein excitations of the electroweak bosons or gravitons. The ATLAS and CMS Collaborations Fig. 1. Dielectron invariant mass distributiob for a 3-TeV 2' (open histogram) and background (shaded histogram), normalized to 30 fb-l.
A lattice calculation of the Isgur-Wise function

Abstract We calculate the Isgur-Wise function (ξ0) by measuring the heavy-heavy meson transition matrix element on the lattice in the quenched approximation. The standard Wilson action is used for both the heavy and the light quarks. Our numerical results are compared with various model calculations and experimental data. In particular, using a linear fit, we find ϱ2=1.24±0.26±0.33 (The slope of ξ0 at the zero-recoil point is −ϱ2). Using instead the parametrization of ξ0 suggested by Neubert and Rieckert and fitting the lattice data up to v· v′∼1.2, we find ϱNR2=1.41±0.19±0.38.
ThermoNet: fine-grain assessment of building comfort and efficiency

Understanding the performance of the heating, ventilation, and air conditioning (HVAC) system in large buildings is a prerequisite for optimizing their energy efficiency. Fine grain performance analysis has not, to our knowledge, received adequate attention thus far. To address this issue we evaluate the thermal comfort and the energy efficiency of a relatively modern HVAC system in a large building based on building-wide high-fidelity environmental data collected via a wireless sensor network over 12 months. Access to fine grain information reveals temporal and spatial dynamics that help quantify the level of (non-)compliance with the system’s control objective and the building’s thermal comfort standards: we find over-conditioning at multiple time scales which offers opportunities for reduced operating cost, and identify building anomalies and ill-conditioned rooms that need maintenance. The paper moreover describes ThermoNet, our hybrid wireless sensor network solution for monitoring a legacy building, which uses duty cycling and adaptive power control to achieve high data yield with low power consumption.