cssi/SciSciGPT-SciSciNet huggingface dataset:
Hadron Form Factors in AdS/QCD

We discuss how to calculate form factors using a holographic model of QCD, mainly focusing on vector, axial, and pseudoscalar mesons. We illustrate the techniques on gravitational form factors (which are useful for constraining the generalized parton distributions) as well as quoting the results for electromagnetic form factors. One striking outcome, comparing the several types of calculated form factors, is that mesons appear noticeably more compact when measured by the gravitational form factors than when measured by the charge form factor.
Feature selection via regularized trees

We propose a tree regularization framework, which enables many tree models to perform feature selection efficiently. The key idea of the regularization framework is to penalize selecting a new feature for splitting when its gain (e.g. information gain) is similar to the features used in previous splits. The regularization framework is applied on random forest and boosted trees here, and can be easily applied to other tree models. Experimental studies show that the regularized trees can select high-quality feature subsets with regard to both strong and weak classifiers. Because tree models can naturally deal with categorical and numerical variables, missing values, different scales between variables, interactions and nonlinearities etc., the tree regularization framework provides an effective and efficient feature selection solution for many practical problems.
Fast Best-Match Shape Searching in Rotation-Invariant Metric Spaces

Object recognition and content-based image retrieval systems rely heavily on the accurate and efficient identification of 2-D shapes. Features such as color, texture, positioning etc., are insufficient to convey the information that could be obtained through shape analysis. A fundamental requirement in this analysis is that shape similarities are computed invariantly to basic geometric transformations, e.g., scaling, shifting, and most importantly, rotations. And while scale and shift invariance are easily achievable through a suitable shape representation, rotation invariance is much harder to deal with. In this work, we explore the metric properties of the rotation-invariant distance measures and propose an algorithm for fast similarity search in the shape space. The algorithm can be utilized in a number of important data mining tasks such as shape clustering and classification, or for discovering of motifs and discords in large image collections. The technique is demonstrated to introduce a dramatic speed-up over the current approaches, and is guaranteed to introduce no false dismissals.
Asymmetric Synthesis of Quaternary α-Amino Phosphonates Using Sulfinimines

The addition of lithium diethylphosphonate to enantiopure ketosulfinimines is highly diastereoselective (>95%), affording the first examples of quaternary α-alkyl α-amino (arylmethyl)phosphonates.
A review of electrostatic wave measurements on auroral magnetic field lines

The review emphasizes experimental evidence for electrostatic waves on auroral zone magnetic field lines. Data were obtained from radar, balloon, rocket, and satellite observations. The paper is organized around three topics: (1) the turbulent density and velocity fields of the magnetospheric flow, (2) instabilities associated with the convection electric field and its interactions with the neutral atmosphere, and (3) waves and discontinuities in the dynamic region at about one earth radius above the auroral zone. Measurements of both the electric field and density fluctuation component of such waves are included. Although this is not a theoretical study, an attempt is made to organize the measurements about the existing theoretical framework.
Economies of scale, learning effects and offshore wind development costs

Abstract This paper presents a model of overnight development costs for offshore wind projects and tests for the presence of economies of scale and learning effects. Both industry-wide and country-specific learning effects are analyzed. Recently, “pilot projects” have been proposed in states such as Maine and New Jersey with the hope of inducing cost savings in future larger utility scale projects. Therefore the impact of country-specific learning effects are of particular importance. The dataset used in the analysis consists of forty-one European offshore wind projects. Research findings do not suggest that the costs exhibit economies of scale, nor do we find robust evidence of either industry-wide or country-specific learning effects.
PROGRESS IN NON-ENZYMATIC SELECTIVE MODIFICATION AND CLEAVAGE OF PROTEINS.

Publisher Summary This chapter discusses the progress in nonenzymatic selective modification and cleavage of proteins. Cyanogen bromide cleaves methionyl bonds in acidic medium in high yields with practically no side reactions. Cleavage of the four methionyl bonds in ribonuclease proceeds in yields up to 85–95%. Gel filtration permits the isolation of an N-terminal 13-unit peptide, free homoserine, and the core. Cyanogen bromide cleavage of sperm whale myoglobin, containing two methionine residues, followed by gel filtration on Sephadex GS-25 and GS-75, has led to the isolation of three peptides in high yield. N-bromosuccinimide and N-bromoacetamide can be used for the selective cleavage of C-tryptophyl and C-tyrosyl bonds and for the selective oxidation of indole to oxindole residues. Tryptophan residues of chymotrypsin are more accessible to oxidation than in di-isopropyl-phosphoryl-chymotrypsin. The difference spectrum of DIP-chymotrypsin (one tryptophan oxidized) versus chymotrypsin (one tryptophan oxidized) is identical with the difference spectrum of DIP-chymotrypsin versus chymotrypsin.
Spatial competition with endogenous location choices: An application to discount retailing

This paper examines the importance of geographical differentiation in store location decisions of firms in the retail discount industry. Using a novel data set that includes the store locations and accompanying market conditions for all stores belonging to the Wal-Mart, Kmart, and Target chains, we study the factors that influence the entry and location decisions of these firms. The model involves an incomplete information game between the three players where each firm has private information about its own profitability. A key feature of our modeling approach is that it permits asymmetries across firms in the impact of exogenous market characteristics and competitive interaction effects. Variations in the exogenous firm specific characteristics, such as the distances from the market to firms’ headquarters and the nearest distribution centers, serve as exclusion restrictions and provide the source for model identification. Parameter estimates of the payoff functions are used to predict the equilibrium market structure under a variety of market conditions that provide insights into the competitive landscape of the industry. Results show that all firms exert a strong negative impact on competitors when they are in close proximity, but the effect decreases with distance to rivals suggesting strong returns to spatial differentiation in this industry. Target stores fare well under competition except when these competitors are in close proximity. Wal-Mart’s supercenter format is found to be the most formidable player as it substantially impacts competitors even at a large distance. We also find significant asymmetries across players in their response to market conditions and competition interactions.
Markov switching negative binomial models: An application to vehicle accident frequencies

In this paper, two-state Markov switching models are proposed to study accident frequencies. These models assume that there are two unobserved states of roadway safety, and that roadway entities (roadway segments) can switch between these states over time. The states are distinct, in the sense that in the different states accident frequencies are generated by separate counting processes (by separate Poisson or negative binomial processes). To demonstrate the applicability of the approach presented herein, two-state Markov switching negative binomial models are estimated using five-year accident frequencies on Indiana interstate highway segments. Bayesian inference methods and Markov Chain Monte Carlo (MCMC) simulations are used for model estimation. The estimated Markov switching models result in a superior statistical fit relative to the standard (single-state) negative binomial model. It is found that the more frequent state is safer and it is correlated with better weather conditions. The less frequent state is found to be less safe and to be correlated with adverse weather conditions.
The Capabilities of the upgraded MIPP experiment with respect to Hypernuclear Physics

We describe the state of analysis of the MIPP experiment, its plans to upgrade the experiment and the impact such an upgraded experiment will have on hypernuclear physics.
Preparation and Reactivity of Ethyl 2-Vinyloxazole-4-carboxylate

The one-step synthesis of ethyl 2-vinyloxazole-4-carboxylate is described. The reactivity of this synthetically useful oxazole fragment towards addition and Heck coupling was examined.
Track reconstruction of normal muon decays in the LAMPF TPC: One working scheme

A working scheme for track reconstruction of normal muon decays in the LAMPF TPC is here outlined. Muon tracks stopping in the TPC and helical electron tracks from muon decay are both identified and fitted for complete event reconstruction. Because of certain geometrical characteristics of the TPC, novel techniques are deployed to find the tracks. Normal road tracing methods do not work reliably; they are replaced by, among other things, a random search technique that locates the helix’s planar projection and a carefully worked‐out method for correctly putting each coordinate on its proper turn in the helix.
Job Redesign, Reform, Enrichment—Exploring the Limitations

American industry has long been committed to redesign of executive and professional jobs with a view to improving the quality of work. Recently this interest in the quality of managerial, professional, and high-level sales jobs has been extended to other white-collar workers. Sometimes reports on these experiments (as well as those involving blue-collar workers) imply and occasionally state that sweeping, even radical, job reform is in the offing and can be undertaken once inertia in the workplace is overcome. But is widespread job reform possible? Is it necessary? This article considers some of the limitations on job reform. But first a few examples of the type and scope of experiments in job redesign should be considered.
Measuring the relative phase of the energy gap in a high-temperature superconductor with EELS

Abstract A method of measuring the relative phase of the energy gap in a high-temperature superconductor is suggested for electron energy loss spectroscopy. Energy-resolved measurements of off-specular scattering should show a feature similar to the specular feature associated with the gap. Unlike the specular feature, which reflects an average of the gap over the (normal) Fermi surface, the energy loss of the off-specular feature depends on the superconducting energy gap at only two locations on the Fermi surface. The onset of the feature reflects the relative phase between these two points. This result is independent of surface characteristics. Such characteristics affect the magnitude of the off-specular feature, not its location or onset. The size of the feature is estimated for a simple surface model. Implications of specific measurements on Bi2Sr2CaCu2O8 are discussed.
Binary Mergers and Growth of Black Holes in Dense Star Clusters

We model the dynamical evolution of primordial black holes (BHs) in dense star clusters using a simplified treatment of stellar dynamics in which the BHs are assumed to remain concentrated in an inner core, completely decoupled from the background stars. Dynamical interactions involving BH binaries are computed exactly and are generated according to a Monte Carlo prescription. Recoil and ejections lead to complete evaporation of the BH core on a timescale ~109 yr for typical globular cluster parameters. Orbital decay driven by gravitational radiation can make binaries merge, and, in some cases, successive mergers can lead to significant BH growth. Our highly simplified treatment of the cluster dynamics allows us to study a large number of models and to compute statistical distributions of outcomes, such as the probability of massive BH growth and retention in a cluster. We find that, in most models, there is a significant probability (~20%-80%) of BH growth with final masses 100 M☉. In one case, a BH formed with mass ≈620 M☉. However, if the typical merger recoil speed (due to asymmetric emission of gravitational radiation) significantly exceeds the cluster escape speed, no growth ever occurs. Independent of the recoil speed, we find that BH-BH mergers enhanced by dynamical interactions in cluster cores present an important source of gravitational waves for ground-based laser interferometers. Under optimistic conditions, the total rate of detections by Advanced LIGO could be as high as a few tens of events per year from inspiraling BHs from clusters.
Suggestion for testing the hypothesis of local compensation of transverse momentum

A description is given of an experimental test of the hypothesis of local compensation of transverse momentum in multiparticle production. This experiment does not require the detection of neutral particles. (AIP)
Supporting government cost planning of industrial wastewater treatment

The 1972 Federal Water Pollution Control Act Amendments established a series of national goals with the purpose of reducing and eliminating water borne pollution in the United States. One of these goals requires the implementation of best practicable control technology by all industrial dischargers by 1977.
Spin symmetry predictions for heavy quarkonia alignment

Abstract We investigate the implications of spin symmetry for heavy quarkonia production and decay. We first compare spin symmetry predictions for charmonia and bottomonia radiative transitions with data and find they agree quite well. We next use spin symmetry along with nonrelativistic QCD power counting to determine the leading order alignment of P- and D-wave orthoquarkonia that are produced through gluon fragmentation. Finally, we discuss a mechanism which may resolve the current factor of 30 discrepancy between theoretical predictions and experimental measurements of prompt ψ′ production at the Tevatron. This mechanism involves gluon fragmentation to a subleading Fock component in the ψ′ wavefunction and yields 100% transversely aligned ψ's to lowest order. Observation of such a large alignment would provide strong support for this resolution to the ψ′ problem.
The effect of hydrophobic surface modification on bulk cohesive strength

The current trend in industry is to add small amounts of very fine or nano-particles to already existing products in hopes that the combination of particles will exhibit some enhanced behavior. A science is developing around the addition of these small particles and the appearance of certain chemical behaviors that they cause in the bulk. In addition, techniques are being developed that allow surface modification of many products. It has become a routine to coat particles with hydrophobic or hydrophilic coatings to achieve certain behaviors in solutions or gels. However, little attention is paid to the effect that these surface modifications and small particle interactions may have on the cohesive nature of the bulk particulate material. One intriguing question to be answered is: can methodologies or theories be postulated to predict the bulk cohesion of a given particle assembly after a prescribed surface modification or the addition of custom nano-particles? This paper examines the strength behavior of hydrophobic particles in moist or wet environments. In some instances the effect of liquid addition to hydrophobic surfaces dramatically reduces the bulk unconfined yield strength. This is likely due to the reduction in inter-particle friction from hydrodynamic effects. However, some particle sizes and degrees of hydrophobicity show an increase of cohesive behavior as moisture is added to the system. Finer particles tend to first exhibit a reduction in strength followed by an increase as the moisture content is increased. In any event, there is a non-linear relationship between particle size, liquid binder content, and the hydrophobic nature of the surface which is examined in this paper.
Reactively secure signature schemes

Protocols for problems like Byzantine agreement, clock synchronization, or contract signing often use digital signatures as the only cryptographic operation. Proofs of such protocols are frequently based on an idealizing “black-box” model of signatures. We show that the standard cryptographic security definition for digital signatures is not sufficient to ensure that such proofs are still valid if the idealized signatures are implemented with real, provably secure signatures.We propose a definition of signature security suitable for general reactive, asynchronous environments, called reactively secure signature schemes, and prove that, for signature schemes where signing just depends on a counter as state, the standard security definition implies our definition.We further propose an idealization of digital signatures that can be used in a reactive and composable fashion, and we show that reactively secure signature schemes constitute a secure implementation of our idealization.
An entropy correction method for unsteady full potential flows with strong shocks

An entropy correction method for the unsteady full potential equation is presented. The unsteady potential equation is modified to account for entropy jumps across shock waves. The conservative form of the modified equation is solved in generalized coordinates using an implicit, approximate factorization method. A flux-biasing differencing method, which generates the proper amounts of artificial viscosity in supersonic regions, is used to discretize the flow equations in space. Comparisons between the present method and solutions of the Euler equations and between the present method and experimental data are presented. The comparisons show that the present method more accurately models solutions of the Euler equations and experiment than does the isentropic potential formulation.
Equivariant K-Theory, Generalized Symmetric Products, and Twisted Heisenberg Algebra

For a space X acted on by a finite group Γ, the product space Xn affords a natural action of the wreath product Γn=Γn⋊Sn. The direct sum of equivariant K-groups \(\) were shown earlier by the author to carry several interesting algebraic structures. In this paper we study the K-groups \(\) of Γn-equivariant Clifford supermodules on Xn. We show that \(\) is a Hopf algebra and it is isomorphic to the Fock space of a twisted Heisenberg algebra. Twisted vertex operators make a natural appearance. The algebraic structures on ℱ−Γ(X), when Γ is trivial and X is a point, specialize to those on a ring of symmetric functions with the Schur Q-functions as a linear basis. As a by-product, we present a novel construction of K-theory operations using the spin representations of the hyperoctahedral groups.
Computational identification of gene-social environment interaction at the human IL6 locus

To identify genetic factors that interact with social environments to impact human health, we used a bioinformatic strategy that couples expression array–based detection of environmentally responsive transcription factors with in silico discovery of regulatory polymorphisms to predict genetic loci that modulate transcriptional responses to stressful environments. Tests of one predicted interaction locus in the human IL6 promoter (SNP rs1800795) verified that it modulates transcriptional response to β-adrenergic activation of the GATA1 transcription factor in vitro. In vivo validation studies confirmed links between adverse social conditions and increased transcription of GATA1 target genes in primary neural, immune, and cancer cells. Epidemiologic analyses verified the health significance of those molecular interactions by documenting increased 10-year mortality risk associated with late-life depressive symptoms that occurred solely for homozygous carriers of the GATA1-sensitive G allele of rs1800795. Gating of depression-related mortality risk by IL6 genotype pertained only to inflammation-related causes of death and was associated with increased chronic inflammation as indexed by plasma C-reactive protein. Computational modeling of molecular interactions, in vitro biochemical analyses, in vivo animal modeling, and human molecular epidemiologic analyses thus converge in identifying β-adrenergic activation of GATA1 as a molecular pathway by which social adversity can alter human health risk selectively depending on individual genetic status at the IL6 locus.
Tender Mercies: Efficient and Equitable Land use Change

A two-tiered, front-end-loaded tender offer system is shown to catalyze a market for partial property rights. This market would obviate any legitimate need for governmental zoning, and thus would put an end to zoning's inefficiency and inequity. The proposed system would facilitate development and redevelopment, cause nuisance producing zones to become more compact, stop the subversion of zoning for fiscal and exclusionary purposes, reduce the opportunities for corruption and end rent seeking as well as “not in my backyard” activities. The proposed tender offer system would fully compensate those who are injured by negative externalities, thereby eliminating adverse distributional effects.
Persistent transport barrier on the West Florida Shelf.

[1] Analysis of drifter trajectories in the Gulf of Mexico has revealed the existence of a region on the southern portion of the West Florida Shelf (WFS) that is not visited by drifters that are released outside of the region. This socalled ‘‘forbidden zone’’ (FZ) suggests the existence of a persistent cross-shelf transport barrier on the southern portion of the WFS. In this letter a year-long record of surface currents produced by a Hybrid-Coordinate Ocean Model simulation of the WFS is used to compute Lagrangian coherent structures (LCSs), which reveal the presence of a persistent cross-shelf transport barrier in approximately the same location as the boundary of the FZ. The location of the cross-shelf transport barrier undergoes a seasonal oscillation, being closer to the coast in the summer than in the winter. A month-long record of surface currents inferred from high-frequency (HF) radar measurements in a roughly 60 km � 80 km region on the WFS off Tampa Bay is also used to compute LCSs, and these also reveal the presence of transient transport barriers. While the HF-radarderived transport barriers cannot be unambiguously linked to the boundary of the FZ, this analysis does demonstrate the feasibility of monitoring transport barriers on the WFS using a HF-radar-based measurement system. The implications of a persistent cross-shelf transport barrier on the WFS for the development of harmful algal blooms on the shoreward side of the barrier are considered. Citation: Olascoaga, M. J., I. I. Rypina, M. G. Brown, F. J.
Review of alternative cooling technologies

Abstract This paper provides an update on alternative cooling technologies in the context of a report by Fischer et al. [2] , which contains an extensive assessment of “not-in-kind” technologies including their state-of-the-art, development issues, and potentials to replace vapor compression equipment. After nearly 20 years, it is now of interest to update the status of alternative technologies considering regulatory actions aimed at refrigerants with high global warming potential. Several technologies are considered with sorption cooling, desiccant cooling, magnetic cooling, thermoacoustic cooling, thermoelectric cooling, and transcritical CO 2 being discussed in some detail. For each technology we present its physical principle, a brief summary of the findings of Fischer et al., the technological advancements since their study leading to the current state-of-the-art, and our assessment as to the potential of each technology to enter the market as a supplement to or replacement of vapor compression equipment in the next 20 year period.
Water-Based Recreational Benefits of Conservation Programs: The Case of Conservation Tillage on U.S. Cropland

Conservation programs are a significant part of farm legislation. The recent farm bill increases funding of conservation programs. One result will likely be the increased adoption of basic environmentally benign farming practices, such as conservation tillage. This would lead to improvements in surface water quality. In this paper, we examine the magnitude of the nonmarket use value benefits of these improvements. The findings indicate that moderate to widespread adoption of practices such as conservation tillage would result in significant nonmarket benefits.
TOTAL SYNTHESIS OF LUOTONIN A

Abstract The synthesis of the cytotoxic alkaloid luotonin A ( 1 ), which has been shown to possess antileukemic activity, has been achieved. The key step in the synthesis is a Friedlander condensation between 2-aminobenzaldehyde and dione 5 .
Interpreting the Variability of Double-Peaked Emission Lines in Active Galactic Nuclei with Stochastically Perturbed Accretion Disk Models

In an effort to explain the short-timescale variability of the broad, double-peaked profiles of some active galactic nuclei, we constructed stochastically perturbed accretion disk models and calculated Hα line profile series as the bright spots rotate, shear, and decay. We determined the dependence of the properties of the line profile variability on the spot properties. We compared the variability of the line profile from the models to the observed variability of the Hα line of Arp 102B and 3C 390.3. We find that spots need to be concentrated in the outer parts of the line-emitting region to reproduce the observed variability properties for Arp 102B. This rules out spot production by star/disk collisions and favors a scenario where the radius of marginal self-gravity is within the line-emitting region, creating a sharp increase in the radial spot distribution in the outer parts. In the case of 3C 390.3, all the families of models that we tested can reproduce the observed variability for a suitable choice of model parameters.
A categorical approach to imprimitivity theorems for C*-dynamical systems

Introduction Right-Hilbert bimodules The categories The functors The natural equivalences Applications Appendix A. Crossed products by actions and coactions Appendix B. The imprimitivity theorems of Green and Mansfield Appendix C. function spaces Appendix. Bibliography.
Francois Jacob 1920–2013

I knew Francois Jacob only slightly and yet, ever since graduate school, he has been my constant companion. Hardly a week has gone by without my asking him what he would think of this or that result, this or that sentence in a paper, and so on. What he would have thought of this impertinence I cannot say, because I never really let him know—the discussion went on mostly in my head. And so on hearing of his death at 92 in Paris, I began to ponder again the source of his powers that were—to me, anyway—magical.
Retention of a Primordial Cold Classical Kuiper Belt in an Instability-Driven Model of Solar System Formation

The cold classical population of the Kuiper Belt exhibits a wide variety of unique physical characteristics, which collectively suggest that its dynamical coherence has been maintained throughout the solar system's lifetime. Simultaneously, the retention of the cold population's relatively unexcited orbital state has remained a mystery, especially in the context of a solar system formation model, that is driven by a transient period of instability, where Neptune is temporarily eccentric. Here, we show that the cold belt can survive the instability, and its dynamical structure can be reproduced. We develop a simple analytical model for secular excitation of cold Kuiper Belt objects and show that comparatively fast apsidal precession and nodal recession of Neptune, during the eccentric phase, are essential for preservation of an unexcited state in the cold classical region. Subsequently, we confirm our results with self-consistent N-body simulations. We further show that contamination of the hot classical and scattered populations by objects of similar nature to that of cold classicals has been instrumental in shaping the vast physical diversity inherent to the Kuiper Belt.
Leading Virtual Teams

Executive Overview Virtual teams, whose members are geographically dispersed and cross-functional yet work on highly interdependent tasks, present unique leadership challenges. Based on our observations, interviews, and survey data, we identify six leadership practices of effective leaders of virtual teams. Specifically, we elaborate how leaders of successful virtual teams: 1) establish and maintain trust through the use of communication technology; 2) ensure that distributed diversity is understood and appreciated; 3) manage virtual work-life cycle (meetings); 4) monitor team progress using technology; 5) enhance visibility of virtual members within the team and outside in the organization; and 6) enable individual members of the virtual team to benefit from the team. These practices of virtual team leaders can be used to establish a foundation for training and developing future virtual team leaders.
FILAMENTATIONS FOR VIRTUAL LINKS

In 2002, Hrencecin and Kauffman defined a filamentation invariant on oriented chord diagrams that may determine whether the corresponding flat virtual knot diagrams are non-trivial. A virtual knot diagram is non-classical if its related flat virtual knot diagram is non-trivial. Hence filamentations can be used to detect non-classical virtual knots. We extend these filamentation techniques to virtual links with more than one component. We also give examples of virtual links that they can detect as non-classical.
Chiral Mixed Phosphorus/Sulfur Ligands for Palladium-Catalyzed Allylic Alkylations and Aminations

The incorporation of C2 symmetry into chiral ligand design is a well-recognized strategy for restricting the number of diastereomeric transition states in metal-catalyzed enantioselective processes.1 Equally powerful stereochemical restrictions may also be realized with chiral ligands lacking C2 symmetry through the use of electronic effects such as the trans influence.2 Such effects are a natural consequence of the use of chiral bidentate ligands equipped with strong and weak donor heteroatom pairs (e.g., PR3/NR3 or PR3/SR2). Such electronic effects have the potential to influence both the stability and reactivity of the intervening diastereomeric reaction intermediates in the catalytic cycle. While mixed phosphorus/nitrogen bidentate ligands incorporating this construct have been applied in enantioselective palladiumcatalyzed nucleophilic alkylation of allylic esters,3 chiral thioether-containing donor ligands have been less well developed.4 As seen in structure A, thioether complexation creates an S-chiral sulfur center; however, a potential liability associated with these ligands is the relatively low barrier to sulfur inversion (15-20 kcal/mol) for transition metal-coordinated thioethers.5 In this paper, we report a new class of mixed phosphorus/sulfur ligands 1-3 that incorporates a metal-bound thioether as a chiral control element in asymmetric catalysis. The utility of these ligands is illustrated in the palladium-catalyzed allylic alkylation6 with enol-malonate and amine nucleophiles.
Design of a 3-Stage ADR for the Soft X-Ray Spectrometer Instrument on the Astro-H Mission

The Japanese Astro-H mission will include the Soft X-ray Spectrometer (SXS) instrument, whose 36-pixel detector array of ultra-sensitive x-ray microcalorimeters requires cooling to 50 mK. This will be accomplished using a 3-stage adiabatic demagnetization refrigerator (ADR). The design is dictated by the need to operate with full redundancy with both a superfluid helium dewar at 1.3 K or below, and with a 4.5 K Joule-Thomson (JT) cooler. The ADR is configured as a 2-stage unit that is located in a well in the helium tank, and a third stage that is mounted to the top of the helium tank. The third stage is directly connected through two heat switches to the JT cooler and the helium tank, and manages heat flow between the two. When liquid helium is present, the 2-stage ADR operates in a single-shot manner using the superfluid helium as a heat sink. The third stage may be used independently to reduce the time-average heat load on the liquid to extend its lifetime. When the liquid is depleted, the 2nd and 3rd stages operate as a continuous ADR to maintain the helium tank at as low a temperature as possible - expected to be 1.2 K - and the 1st stage cools from that temperature as a single-stage, single-shot ADR. The ADR's design and operating modes are discussed, along with test results of the prototype 3-stage ADR.
Organic synthesis using biocatalytically generated intermediates

Abstract Biocatalytically generated enantiopure intermediates are exceptionally valuable as starting materials in the syntheses of enantiopure complex organic compounds. Cyclic intermediates are particularly useful because of their inherent tendency to undergo highly diastereoselective transformations. Techniques such as the asymmetrization of meso compounds making either enantiomer available in superior yields, and the employment of enzymes at low temperatures giving improved enantioselectivities promise to facilitate the preparation of such intermediates. Because of their functional group compatibility, their environmentally safe nature, and often their low cost, biocatalysis have become a well recognized means of introducing enantiopurity in organic synthesis.
Calculation of critical temperatures from the number of carbons in organic molecules

The linearity of homolog critical temperatures (Tc,K) with the logarithms of chain length (the latter represented by molecular weight, M, or number of carbons, Nc) was used to develop simple equations correlating Tc,K with M (or with Nc+k) for 40 homologous series. Critical temperatures defined by the equations are presumed to be correct, whereas those in substantial disagreement are considered wrong. The equations can be used to estimate many new critical temperatures by interpolation or by prudent extrapolation.
Before and after 2000: revenue and high tech valuation

Purpose – This paper aims to examine the concerns that high‐tech “new economy” companies employ aggressive revenue recognition practices to boost stock prices.Design/methodology/approach – The authors test empirically the hypothesis that revenue is more value relevant than other key performance measures traditional earnings and operating cash flows, especially in the case of high‐tech firms with losses.Findings – Test results from this study demonstrate the association between stock prices and reported revenues, both before and after year 2000 the stock market meltdown.Research limitations/implications – The study limits its scope on the high‐tech new economy sector. The findings may not be applicable to other industries.Practical implications – An important implication of the findings is that the association between stock prices and revenue is presumably the underlying reason for aggressive revenue recognition.Originality/value – This paper provides empirical evidence demonstrating the association betwee...
A trade theorist's take on skilled-labor outsourcing

Abstract Recent concern has attended the phenomenon of skilled-labor outsourcing, in which firms in the United States and other advanced countries have drawn upon the services of skilled workers in developing countries for activities that they used to do at home. Motivated by this and the fact that such outsourcing would be hard to explain without technological differences, this paper explores theoretically a simple story of outsourcing in which factor proportions and technology interact across activities performed within industries or firms. The model has a single sector in which a final output is produced from two activities that differ in their intensity of use of skilled and unskilled labor. In one activity, the developed world (North) has a technical advantage. In the other it does not, but a new regime makes it possible to outsource it to the developing world (South). The paper shows that this outsourcing, if the countries continue to diversify, causes the wage of unskilled labor in North to fall below that in South. However, if factor endowments differ enough to lead to specialization, then it becomes possible for both factors in North to gain from this form of outsourcing.
Enantioselective Construction of Quaternary Stereogenic Carbon Atoms by the Lewis Base Catalyzed Additions of Silyl Ketene Imines to Aldehydes

Silyl ketene imines derived from a variety of α-branched nitriles have been developed as highly useful reagents for the construction of quaternary stereogenic centers via the aldol addition reaction. In the presence of SiCl4 and the catalytic action of chiral phosphoramide (R,R)-5, silyl ketene imines undergo extremely rapid and high yielding addition to a wide variety of aromatic aldehydes with excellent diastereo- and enantioselectivity. Of particular note is the high yields and selectivities obtained from electron-rich, electron-poor, and hindered aldehydes. The nitrile function serves as a useful precursor for further synthetic manipulation.
Production and Storage of Ice for Cooling Buildings

A strategy that may provide economic benefits in buildings is to use an ice production system to provide cool storage for later use when cooling is needed. Understanding the fundamental dynamics of the storage tank is critical in determining the feasibility of such strategies. For this purpose, a lumped parameter model of ice growth on a heat exchanger submerged in a water storage tank is described. Results of an experimental study of an ice storage system installed in a residential research facility are also presented. The results of a parametric study are also presented that show some of the effects of geometric and operating variables on system performance. Trends exhibited in the results suggest ways to optimize ice production for the particular heat exchanger geometry studied.
Linearizing non-linear inverse problems and an application to inverse backscattering

Abstract We propose an abstract approach to prove local uniqueness and conditional Holder stability to non-linear inverse problems by linearization. The main condition is that, in addition to the injectivity of the linearization A, we need a stability estimate for A as well. That condition is satisfied in particular, if A ∗ A is an elliptic pseudo-differential operator. We apply this scheme to show uniqueness and Holder stability for the inverse backscattering problem for the acoustic equation near a constant sound speed.
Jet Circulation Control Airfoil for VTOL Rotors

Based on the potential flow theory calculation, the capacity of the air supply, the limitation of the internal pressure of the model and the limitation due to the compressibility effect of the jet stream at high velocities, the elliptical airfoils of 18 and 12% thickness ratios were designed and constructed. Experimental investigations for both models with trailing-edge jets include force and pitching moment measurements. In addition, static pressure measurements were made in both span wise and chord wise directions. These results were used to compare with available theories as well as other experimental data. Circulation control with dual jets for the elliptical airfoil of 18% thickness ratio was tested with very satisfactory results. The determination of the aerodynamic response of the airfoil model to cyclic changes in jet mass flow was also made. The cyclic results were very satisfactory and are presented in the form of pulsating lift coefficient, drag coefficient, and pressure coefficient as a function of pulsating jet coefficient.
Regiospecificity in the cyclization of 6-(1-hydroxyalkyl) geraniol derivatives. A simple route to the taxol a-ring system

Abstract Readily available derivatives of geraniol bearing a 1-hydroxyalkyl side chain in the 6-position undergo acid-catalyzed regiospecific cyclization to form cyclogeraniol derivatives which have an interesting relation to ring A of taxol.
Addition of Carbamoylsilanes to Electrophilically Substituted Alkenes. Preparation of β-Functionalized Tertiary Amides

The Si−C bond of N,N-dimethylcarbamoylsilanes added regiospecifically to the CC bond of electrophilically functionalized alkenes to afford β-silyl-β-functionalized amides. Carbonyl addition products were formed when hindered alkenic esters were used.
Reconstruction From Anisotropic Random Measurements

Random matrices are widely used in sparse recovery problems, and the relevant properties of matrices with i.i.d. entries are well understood. This paper discusses the recently introduced restricted eigenvalue (RE) condition, which is among the most general assumptions on the matrix, guaranteeing recovery. We prove a reduction principle showing that the RE condition can be guaranteed by checking the restricted isometry on a certain family of low-dimensional subspaces. This principle allows us to establish the RE condition for several broad classes of random matrices with dependent entries, including random matrices with sub-Gaussian rows and nontrivial covariance structure, as well as matrices with independent rows, and uniformly bounded entries.
Curricular policy as a collective effects problem: A distributional approach

Current educational policies in the United States attempt to boost student achievement and promote equality by intensifying the curriculum and exposing students to more advanced coursework. This paper investigates the relationship between one such effort - California's push to enroll all 8th grade students in Algebra - and the distribution of student achievement. We suggest that this effort is an instance of a "collective effects" problem, where the population-level effects of a policy are different from its effects at the individual level. In such contexts, we argue that it is important to consider broader population effects as well as the difference between "treated" and "untreated" individuals. To do so, we present differences in inverse propensity score weighted distributions investigating how this curricular policy changed the distribution of student achievement. We find that California's attempt to intensify the curriculum did not raise test scores at the bottom of the distribution, but did lower scores at the top of the distribution. These results highlight the efficacy of inverse propensity score weighting approaches for examining distributional differences, and provide a cautionary tale for curricular intensification efforts and other policies with collective effects.
Synchronization and phase lock of two mode-locked femtosecond lasers

Two independent mode-locked femtosecond lasers are synchronized to an unprecedented precision. The rms timing jitter between the lasers is 4.3 fs observed within a 160 Hz bandwidth over tens of seconds, or 26 fs within a 50 kHz bandwidth. Novel multi-stage phase locked loops help to preserve this ultrahigh timing resolution throughout the entire delay range between pulses (10 ns). We also demonstrate that the same level of synchronization can be achieved with two lasers at different repetition frequencies. Under such synchronization, phase lock between the carrier frequencies of the two fs lasers has been achieved.
Chirality change in string theory

It is known that string theory compactifications leading to low energy effective theories with different chiral matter content (e.g. different numbers of standard model generations) are connected through phase transitions, described by non-trivial quantum fixed point theories. We point out that such compactifications are also connected on a purely classical level, through transitions that can be described using standard effective field theory. We illustrate this with examples, including some in which the transition proceeds entirely through supersymmetric configurations.
Iron-catalyzed cycloaddition of alkynenitriles and alkynes.

The combination of Fe(OAc)2 and an electron-donating, sterically hindered pyridyl bisimine ligand catalyzes the cycloaddition of alkynenitriles and alkynes. A variety of substituted pyridines were obtained in good yields.
Is there a discipline of educational psychology

(1968). Is there a discipline of educational psychology? Educational Psychologist: Vol. 5, No. 3, pp. 1-9.
A General Method for the Catalytic Nazarov Cyclization of Heteroaromatic Compounds

A general, catalytic method for efficient Nazarov cyclization of systems containing heteroaromatic components has been developed. Scandium triflate was identified as the most reactive promoter, and it was found that addition of lithium perchlorate was necessary for synthetically useful catalytic cyclizations. The method was used to synthesize a range of cyclopentanone-fused heteroaromatic systems in 36−97% yield, and the reactivity trends observed demonstrate the impact of polarization on cyclization efficiency.
Bank characteristics and stock reactions to federal funds rate target changes

This study investigates how bank characteristics affect bank stock reactions to changes in the federal funds rate target. Using a data set of all publicly listed banks of the United States from October 1988 through December 2007, we find that (1) the effect of changes in the federal funds rate target is more pronounced on large banks than on small banks; (2) banks that rely more on nondeposit funding sources are more responsive to such changes; (3) banks with higher capital ratios are less sensitive to unexpected target changes, but when the ratio increases to a certain level, the marginal effect diminishes. We observe that business activity mix does not matter to banks’ sensitivity to monetary shocks. This study is among the first to investigate how bank stock sensitivity to monetary shocks is conditional on various bank characteristics.
Value Assumptions in Recent Research on Migration

(1961). Value Assumptions in Recent Research on Migration. The Sociological Quarterly: Vol. 2, No. 4, pp. 263-279.
Latest Developments In Fiber Manufacture By VAD

Recent progress on the VAD process is described with the performance of VAD fibers in mass production basis. Some of the latest developments of VAD technologies, such as fluorine-added fibers and high-speed deposition techniques are also discussed.
A Variation, with a Period of Two Solar Cycles, in the Cosmic‐Ray Diurnal Anisotropy

Annual means, 1937-1965, of the cosmic-ray diurnal anisotropy component, in the asymptotic direction 128°E of the sun, are well-fitted by a wave with a period of 20 years, which is twice the solar cycle period of 10 years for the interval 1937–1965. This variation is independent of magnetic activity, and when removed the residual variations combine with those in the asymptotic component 387deg;E of the sun (in which there is no 20-year wave) to give resultant variations, which are principally in the asymptotic component 90°E of the sun. Yearly means of this resultant component are well correlated (r = +0.75) with magnetic activity, U0, and, on the average, vanish for U0 = 0. U0 is the absolute value of the southward geomagnetic component of the so-called equatorial ring current [Forbush, 1966].
Health Insurance and Precautionary Saving

Recent studies stress precautionary motives for saving: with uncertain income and health, households may accumulate wealth to guard against lower consumption in the future. This paper examines the relationship between health insurance and savings, using high-quality data on household finances. The precautionary view predicts higher savings among households without insurance, ceteris paribus. I find that insurance does reduce saving, once the endogeneity of coverage is taken into account.