cssi/SciSciGPT-SciSciNet huggingface dataset:
Microstructural Evolution and Magnetic Properties of NiFe2O4 Nanocrystals Dispersed in Amorphous Silica

NiFe_2O_4 nanocrystals were dispersed in silica by a sol−gel route. The dried gel was amorphous, in which isolated Fe^(3+) ions had a weak interaction with silica matrix, as characterized by a weak IR absorption at ca. 580 cm^(-1). Heat treatment at 400 °C resulted in nickel ferrite clusters being partially formed, and these clusters were observed to interact with the matrix through Si−O−Fe bonds. This interaction reached its maximum with the complete formation of NiFe_2O_4 clusters as the temperature was raised to 600 °C. Above this temperature, NiFe_2O_4 clusters grew larger into nanocrystals, while the interaction between the nanocrystals and silica matrix disappeared with breakage of Si−O−Fe bonds. The grain growth for magnetic nanoparticles was accompanied with rearrangement of amorphous silica network. The preference of forming NiFe_2O_4 nanocrystals eliminated the possibility of precipitation of crystallite component oxides, e.g., NiO, γ-Fe_2O_3, or Fe_3O_4 in amorphous silica matrix, or crystalline silica, e.g., cristobalite or quartz, even when the treatment temperature was 1100 °C. Fe ions in silica glasses were determined by Mossbauer spectroscopy to be present exclusively as Fe^(3+) ions in a high-spin state at octahedral coordination, and the chemical environment of the Fe^(3+) ions seemed to remain unchanged until the nickel ferrite clusters crystallized. The formation mechanism for NiFe_2O_4 nanocrystals can be explained in terms of Ni^(2+) ions shifting from the tetrahedral centers to undistorted octahedral sites in the spinel lattice and the partial transformation of FeO_6 octahedron to FeO_4 tetrahedron. The critical dimension for the NiFe_2O_4 nanocrystals in silica was detected as ca. 9 nm. Below the critical size, NiFe_2O_4 nanocrystals had a superparamagnetic single-domain structure, while the nanocrystals with particle sizes larger than the critical size exhibited bulklike behavior.
Atomistic simulation of point defects and diffusion in B2 NiAl

NiAl is a strongly ordered compound with a large atomic size difference between the components. Due to these features it demonstrates the so-called triple-defect mechanism of compositional disorder with Ni anti-structural atoms in Ni-rich compositions and Ni vacancies in Al-rich compositions. Diffusion mechanisms in triple-defect compounds are more involved than in antisite disorder compounds. Because every Ni atom in the B2 structure is surrounded by Al atoms and vise versa, every nearest-neighbor (NN) jump of a vacancy induces local disorder, which is very unfavorable. The authors therefore have to consider diffusion of Ni and Al along their own sublattices by next-nearest-neighbor (NNN) vacancy jumps. Alternatively, one can think of cycled mechanisms in which the crystal order is destroyed only locally and temporarily, but is totally restored when the diffusion cycle is complete. In this study the authors apply molecular statics simulations to evaluate the energetics of the point defect formation and migration in NiAl by different mechanisms. The goal of their simulations is to predict the mechanisms that are the easiest, thus dominating, at different alloy compositions.
Detection of the Kuiper bands in the spectrum of Titan

Abstract 3ew spectra of Titan centered at 7500 A, at resolutions of 4 and 1 A are presented. Weak absorptions coincident with features observed in the spectra of Uranus and Neptune are found. This observation suggests methane abundances in excess of 1 km-am, thereby emphasizing the complexity of line formation in Titan's atmosphere. The question of the total atmospheric pressure of Titan must be reexamined.
HTLV-1 Tax mediated downregulation of miRNAs associated with chromatin remodeling factors in T cells with stably integrated viral promoter

RNA interference (RNAi) is a natural cellular mechanism to silence gene expression and is predominantly mediated by microRNAs (miRNAs) that target messenger RNA. Viruses can manipulate the cellular processes necessary for their replication by targeting the host RNAi machinery. This study explores the effect of human T-cell leukemia virus type 1 (HTLV-1) transactivating protein Tax on the RNAi pathway in the context of a chromosomally integrated viral long terminal repeat (LTR) using a CD4(+) T-cell line, Jurkat. Transcription factor profiling of the HTLV-1 LTR stably integrated T-cell clone transfected with Tax demonstrates increased activation of substrates and factors associated with chromatin remodeling complexes. Using a miRNA microarray and bioinformatics experimental approach, Tax was also shown to downregulate the expression of miRNAs associated with the translational regulation of factors required for chromatin remodeling. These observations were validated with selected miRNAs and an HTLV-1 infected T cells line, MT-2. miR-149 and miR-873 were found to be capable of directly targeting p300 and p/CAF, chromatin remodeling factors known to play critical role in HTLV-1 pathogenesis. Overall, these results are first in line establishing HTLV-1/Tax-miRNA-chromatin concept and open new avenues toward understanding retroviral latency and/or replication in a given cell type.
Major depressive disorder

Major depressive disorder (MDD) is now an accepted disorder in children and adolescents; genetic studies and data that support a dysregulation of one or more neurotransmitter systems suggest that biological factors play an important role in MDD in children and adolescents.
A short synthesis of an important precursor to a new class of bicyclic β-lactamase inhibitors

Abstract A short synthesis of an important precursor to known bicyclic β-lactamase inhibitors is described. The synthesis uses commercially available trans-3- hydroxy- l -proline 1. Protection of the amino group followed by formation of the hydroxamate and cyclization using Mitsunobu conditions afforded bicyclic β-lactam 4 in three steps in 53% overall yield.
Mechanism of electron conduction in self-assembled alkanethiol monolayer devices

Electron tunneling through self-assembled monolayers (SAM's) of alkanethiols is investigated using nanometer-scale devices. Temperature-dependent current-voltage measurements are performed on alkanethiol SAM's to distinguish between different conduction mechanisms. Temperature-independent electron transport is observed, proving that tunneling is the dominant conduction mechanism of alkanethiols, as well as exhibiting an exponential dependence of tunneling current on the molecule length with a decay coefficient \ensuremath{\beta}. From the bias dependence of \ensuremath{\beta}, a barrier height ${\ensuremath{\Phi}}_{B}$ of $1.39\ifmmode\pm\else\textpm\fi{}0.01\mathrm{eV}$ and a zero-field decay coefficient ${\ensuremath{\beta}}_{0}$ of $0.79\ifmmode\pm\else\textpm\fi{}0.01{\AA{}}^{\ensuremath{-}1}$ are determined for alkanethiols.
A description of the IBM 7074 system

A new data processing system, the IBM 7070, was described at the 1958 Eastern Joint Computer Conference. Recent progress has resulted in the creation of an expanded family of 7070 systems, exemplified by the announcement of the IBM 7074 system.The 7074 represents a dramatic new approach to data processing system growth, and is the second major step in the 7070 data system family. It is not an entirely new system, but rather an improvement within the 7070 framework. It enables a customer whose workload has outgrown his 7070 equipment to upgrade his system over a weekend, thus achieving multiplied performance without reprogramming and without excessive disruption of his operation.Specifically, the increased performance is achieved by use of:1. A new, high-performance arithmetic and program unit called the 7104 high-speed processor.2. Improved-performance storage units, the 7301 models 3 and 4, which operate on a four-μ sec cycle instead of the six-μ sec cycle used with the basic 7070.These units are substituted for their counterparts in the 7070 system.Compared to a two-channel 7070 system using 729 IV tape drives, a 7074 of the same configuration has the following performance characteristics:Internal performance on commercial work: 6 × 7070Thruput or job performance on commercial work: 2 × 7070Floating point performance on scientific work: 10 × 7070Internal performance is a measure of instruction-execution time. It is measured on the basis of the mix of instructions executed in a group of programs considered typical of commercial applications.Thruput or job performance considers, in addition to instruction-execution time, the time expended in magnetic-tape input/output operations. A typical mix of commercial jobs--including sorting, merging, high and low activity-file maintenance, and editing--provides the basis for this comparison.Floating point performance is measured on the basis of a typical group of arithmetic and logical instructions encountered in many scientific problems. It is essentially a measure of internal speed.
ATOMIC AND MOLECULAR CARBON AS A TRACER OF TRANSLUCENT CLOUDS

Using archival, high-resolution far-ultraviolet Hubble Space Telescope/Space Telescope Imaging Spectrograph spectra of 34 Galactic O and B stars, we measure C I column densities and compare them with measurements from the literature of CO and H2 with regard to understanding the presence of translucent clouds along the line of sight. We find that the CO/H2 and CO/C I ratios provide good discriminators for the presence of translucent material, and both increase as a function of molecular fraction, fN = 2N(H2)/N(H). We suggest that sightlines with values below CO/H2 ≈10–6 and CO/C I ≈1 contain mostly diffuse molecular clouds, while those with values above sample clouds in the transition region between diffuse and dark. These discriminating values are also consistent with the change in slope of the CO versus H2 correlation near the column density at which CO shielding becomes important, as evidenced by the change in photochemistry regime studied by Sheffer et al. Based on the lack of correlation of the presence of translucent material with traditional measures of extinction, we recommend defining "translucent clouds" based on the molecular content rather than line-of-sight extinction properties.
Review on the influence of hydrogen on the magnetism of alloys based on rare earth-transition metal systems

Extensive studies of the magnetism of metal hydrides have been carried out in the last three decades. Hydrogenation of metals and intermetallic compounds frequently results in a striking alteration of their electronic and magnetic characteristics and leads to some extraordinary new features. In materials which contain a transition metal, the effect of hydrogen on the magnetic properties is twofold: Firstly, from the band structure point view, since hydrogen contributes two states and only one electron, the Fermi level, and hence the transition metal magnetic moment, is affected. Secondly hydrogen absorption results in increased lattice dimensions, which influences the strength of the interaction between magnetic ions. One of the most striking effects of hydrogen absorption is observed in the intermetallic compounds Th 7 Fe 3 H 30 . In this instance, the parent material is a superconductor, but upon hydrogenation it becomes magnetically ordered. The class of compounds based on R 6 T 23 (R = rare earth, T = Mn, Fe) has shown dramatic magnetic structure change upon hydrogenation. For example, on hydrogenation, Y 6 Mn 23 transforms from a ferrimagnet to an antiferromagnet. The influence of hydrogen on the magnetic properties and crystal structure of rare earth-transition metal-based intermetallic compounds with RT 2 , RT 3 , R 6 T 23 , R 2 T 14 B and R 6 T 13 X structure type (R=rare earth, T=Fe, Co or Mn and X = the third, fourth and fifth group of elements in the periodic table) is reviewed.
SHAPE OPTIMIZATION OF DENTAL IMPLANT DESIGNS UNDER OBLIQUE LOADING USING THE p-VERSION FINITE ELEMENT METHOD

The aim of this study was to introduce design optimization of an endosseous dental implant in order to minimize cortical bone strains at the crest of the implant/bone interface. Linear elastic p-version finite element analysis was used to find the optimal design in four different two-dimensional finite element models of the mandibular bone: model 1 (medium density cancellous bone and 2 mm thickness of cortical bone), model 2 (low density cancellous bone and 2 mm thickness of cortical bone), model 3 (medium density cancellous bone and 1 mm thickness of cortical bone), model 4 (low density cancellous bone and 1 mm thickness of cortical bone). Shape of the implant was evaluated with respect to its length and diameter, as well as the presence or absence of taper in the neck. Implants with maximum length, maximum diameter, and no taper had the lowest crestal strains in models 1, 3, and 4. Taper in the neck of the implant increased the strains in models 1, 3, and 4. In cases of poor quality of bone, increasing the diameter of the implant appeared to be the most effective means of reducing crestal bone strains.
An expeditious approach to access 2-arylimidazo[1,2-a]pyridin-3-ol from 2-amino pyridine through a novel Petasis based cascade reaction

An expeditious cascade protocol for the synthesis of functionalized imidazo[1,2-a]pyridin-3-ols was developed based on the Petasis reaction. With the availability of commercial reagents and high efficiency in expanding molecule diversity, this methodology is superior to the existing procedures for the synthesis of imidazo-pyridin-3-ol analogues.
A Model of Welfare Competition with Evidence from AFDC

In this paper, we test empirically for strategic behavior among the states using the cash support program Aid to Families with Dependent Children (AFDC). To motivate the empirical work, we adapt Wildasin’s model of income redistribution (1991, American Economic Review; 81, 757‐773) to a model of “interjurisdictional welfare competition.” Although welfare competition may be generated from different frameworks, we choose Wildasin’s model to illustrate how welfare benefit interdependence is genereated in the context of welfare migration. We estimate a “representative reaction function” for AFDC using both cross sections and pooled cross-section data. After controlling for other determinants of AFDC benefit levels and for spatial error autocorrelation, we find evidence showing competition. © 2000 Academic Press
Studies of multiplicity in relativistic heavy-ion collisions

In this talk I'll review the present status of charged particle multiplicity measurements from heavy-ion collisions. The characteristic features of multiplicity distributions obtained in Au+Au collisions will be discussed in terms of collision centrality and energy and compared to those of p+p collisions. Multiplicity measurements of d+Au collisions at 200 GeV nucleon-nucleon center-of-mass energy will also be discussed. The results will be compared to various theoretical models and simple scaling properties of the data will be identified.
Evaluating Estimates of Materials Offshoring from U.S. Manufacturing

Abstract When materials offshoring is measured by estimating imported intermediate inputs, a common assumption used is that an industry’s imports of each input, relative to its total demand, is the same as the economy-wide imports relative to total demand: this is the so-called “import comparability” or “proportionality” assumption. A report to the National Research Council identified this assumption as being a significant limitation of current data collection and analysis. In this note we move beyond this assumption to obtain a direct measure of imported materials by industry for the United States in 1997. At the 3-digit I–O industry level, there is a correlation of 0.68 between the offshoring shares made with and without the proportionality assumption, and a higher correlation of 0.87 when the shares are value weighted. While most value-weighted industries have differences below 50 percentage points in the two estimates, there are a significant number of cases that differ by 10 percentage points or more.
The differential impact of privately and publicly funded R&D on R&D investment and innovation: the Italian case

This paper explores the impact of a specific R&D policy instrument, the Italian Fondo per le Agevolazioni della Ricerca (FAR), on industrial R&D and technological output at the firm level. Our objective is threefold: first, to identify the presence or absence of private R&D investment additionality/crowding-out within a pooled sample and in various firm subsets (identified by region, size, level of technology, and other features), while also taking into account the effect of single policy instruments or mixes of them. Secondly, to analyse the output (innovation) additionality by comparing the differential impact of privately funded R&D and publicly funded R&D expenditure on applications for patents filed by firms. Thirdly, the paper will compare the structural characteristics of firms showing additionality with those of firms showing crowding-out, in order to determine the firm characteristics associated with successful policy interventions. Our results suggest that FAR is effective in the pooled sample, ...
Efficient collective communication in distributed heterogeneous systems

With recent advances in high-speed networks, distributed heterogeneous computing has emerged as an attractive computational paradigm. Wide-area grid infrastructures will enable distributed applications-such as video conferencing and distributed interactive simulation--to seamlessly integrate collections of heterogeneous workstations, multiprocessors, and mobile nodes. The underlying network is typically a collection of several heterogeneous links, of different networking technologies. Such a heterogeneous network is also typical in local area workstation clusters, which are increasingly being used as alternatives to parallel computing systems. This paper introduces a framework for developing efficient collective communication schedules over such heterogeneous networks. We focus on application-level communication, between processes of a parallel program. Our framework consists of analytical models of the heterogeneous system, scheduling algorithms for the collective communication pattern, and performance evaluation mechanisms. We show that previous models, which considered node heterogeneity but ignored network heterogeneity, can lead to solutions which are worse than the optimal by an unbounded factor. We then introduce an enhanced communication model, and develop three heuristic algorithms for the broadcast and multicast patterns. The completion time of the schedule is chosen as the performance metric. The heuristic algorithms are fastest edge first (FEF), earliest completing edge first (ECEF), and ECEF with look-ahead. For small system sizes, we find the optimal solution using exhaustive search. Our simulation experiments indicate that the performance of our heuristic algorithms is close to optimal. For performance evaluation of larger systems, we have also developed a simple lower bound on the completion time. Our heuristic algorithms achieve significant performance improvements over previous approaches.
Reference Trajectories From GPS Measurements

A closed-form solution of the GPS pseudorange equations, an unaided Kalman filter, and an inertially-aided Kalman filter are used with differential GPS postprocessing to produce reference trajectories for evaluation of GPS user-equipment, for evaluation of integrated host vehicle navigation, and for accurate Time Space Position Information over large operating areas. The closed-form solution was developed in a derivation of existence conditions for solutions to GPS pseudorange equations. The derivation is included here as an Appendix. Positions calculated from the closed-form solution are used for starting and monitoring the Kalman filters, and for responding to uploads and constellation changes. Custom interface modules adapt common core modules of the aided Kalman filter to various inertial navigators.
Direct conversion of benzylic and allylic alcohols to phosphonates.

Benzyl phosphonate esters often serve as reagents in Horner−Wadsworth−Emmons reactions. In most cases, they can be prepared from benzylic alcohols via formation of the corresponding halide followed by an Arbuzov reaction. To identify a more direct synthesis of phosphonate esters, we have developed a one-flask procedure for conversion of benzylic and allylic alcohols to the corresponding phosphonates through treatment with triethyl phosphite and ZnI2.
Determinants of Vessel Targeting in Vasculitis

Studies of autoimmune diseases have not yet elucidated why certain organs or vessels become the objects of injury while others are spared. This paper explores the hypothesis that important differences exist in regions of the aorta; these regional variations determine vulnerability to such diseases as atherosclerosis, aortitis, giant-cell arteritis, and Takayasu's disease. The reader is invited to reassess two issues: (1) whether the aorta is indeed a single homogeneous structure; and (2) whether the initial stage of aortitis (and indeed other diseases considered "autoimmune") may primarily be the result of acquired alterations of substrate that influence unique immune profiles, but that by themselves may not be pathogenic. Disease susceptibility and patterns are influenced by many factors that are either inborn or acquired. Examples include genetic background, gender, ethnicity, aging, prior and concomitant illnesses, habits, diet, and exposure to toxins and other environmental hazards. Studies of vascular diseases must assess how such variables affect regional anatomic differences in endothelial cells, subendothelial matrix, and vascular smooth muscle, as well as the response of each to a variety of stimuli.
Investor Sentiment and Short-Term Returns for Size-Adjusted Value and Growth Portfolios

We examine the sentiment levels of individual investors relative to subsequent short-term market returns for 1992–2010. We find that sentiment, proxied by percentage of investors who are “bullish” on the market, is significantly negatively related to the subsequent three- and six-month performance of the market. The negative relationship is consistent with the contrarian notion of sentiment. In other words, high (low) levels of bullishness tend to be followed by subsequent low (high) returns. This is true even with the inclusion of standard control explanatory variables (Fama-French [1993]). While the significant results hold for the overall market, they are clearly driven by growth, rather than value stocks. Contrary to some earlier studies, we also note significant explanatory power for sentiment when looking at returns of small-, mid-, and large-cap growth stocks. We also noted that the long-term moving average of monthly bullishness increased from 33.3% to 39.0% over the last 18 years. In our study pe...
[P3Se7]3−: A Phosphorus-Rich Square-Ring Selenophosphate

The new compound Cs10P8Se20 features the heterotetracyclic [P3Se7]3− anion, a phosphorus-rich four-membered-ring species that possesses a P−P−P unit and formally P3+ and P4+ centers. It crystallizes in the orthorhombic space group Pnnm with a = 26.5456(7) A, b = 8.0254(2) A, c = 11.9031(4) A, and Z = 2 at 100(2) K. The cyclic anion is cocrystallized with a [P2Se6]4− anion. Electronic absorption, Raman, Fourier transform infrared, and solid-state 31P NMR spectroscopy studies of Cs10P8Se20 are reported.
Infrastructure Management as Cooperative Work: Implications for Systems Design

This study looks at the data communications network management organization (NMO) within a large financial institution and applies concepts from Computer-Supported Cooperative Work (CSCW) and other domains to develop techniques for describing work within this and other similar organizations. Network management is one form of infrastructure management, which is comprised of two kinds of work: real-time supervisory control work and design work. While many studies of group work focus on the activities of small groups of people engaged in either real-time supervisory control or design work, examinations of organizations where both kinds of work occur are relatively rare. The focus is on the work patterns and data forms that are found within the NMO. Some of the implications of the analysis in regard to the design of CSCW systems are presented and discussed.
Sequential elections and overlapping terms: voting for US Senate

Abstract This paper presents a model in which voters attempt to balance the ideological positions of their Senate representatives. Candidate positions are determined endogenously through a primary system. The median voter theorem is applied in each election to determine winning platforms based on voter preferences which may differ from their individual bliss points. Contrary to the original median voter theorem, the main implications of this model are that: (i) convergence on platform positions is not achieved in the general election, and (ii) extremist candidates defeat moderates in the stable long-run equilibrium.
Calpactins: calcium-regulated membrane-skeletal proteins.

The calpactins are a novel group of proteins associated with the membrane skeleton. The two main forms, calpactin I and II, have been shown to bind to the cytoskeletal proteins actin and spectrin, as well as to anionic phospholipids, which may imply some sort of bridging role. By raising monoclonal antibodies to the heavy and light chains of calpactin I, and to calpactin II, the protein subunits were shown to be coordinately expressed, and the existence of separate calpactin pools hypothesized. Calcium-binding studies suggest that the calpactins may translate Ca2+ signals into cellular responses at the membrane. Structural studies have revealed two distinct domains and are beginning to throw light on heavy--light chain interaction and cytoskeletal attachment.
THE PRICING OF EQUITY CARVE-OUTS DURING THE 1990s

We examine the level of underpricing and characteristics of equity carveouts (ECOs) from 1990 to 1998 (the 1990s) and from 1999 to 2000 (the bubble period). For a sample of 458 ECOs, we find a mean initial return of 8.75% for the 1990s and 47.76% for the bubble period. The results suggest that, similar to other initial public offerings (IPOs), ECOs have been more willing to accept underpricing through time because of an increased importance in analyst coverage and the increased use of spinning, the practice where investment bankers allocate IPOs to high-profile customers to garner potential future business.
The effect of palladium on hydrogen absorption and mobility in AISI 4130 steels

Abstract The effect of palladium in solid solution on the hydrogen absorption and mobility were investigated by cathodic polarization and hydrogen permeation techniques in 1 N NaOH. Palladium additions led to a higher hydrogen permeation rate due to an increased diffusivity and a decreased hydrogen trapping effect. No significant differences were seen in the cathodic polarization parameters as a result of palladium additions. Results of this investigation in conjunction with previous field ion microscopy and autoradiography investigations show that palladium segregates to potential hydrogen traps like MnS inclusions and subsequently repels hydrogen, thereby rendering potential traps innocuous. Results of a palladium ion beam implanted steel are also presented to compare the behavior of palladium surface enriched steels with the steels which have palladium in solid solution.
LONG-TIME STABILITY OF MULTI-DIMENSIONAL NONCHARACTERISTIC VISCOUS BOUNDARY LAYERS

We establish long-time stability of multi-dimensional noncharacteristic boundary layers of a class of hyperbolic–parabolic systems including the compressible Navier–Stokes equations with inflow [outflow] boundary conditions, under the assumption of strong spectral, or uniform Evans, stability. Evans stability has been verified for small-amplitude layers by Gues, Metivier, Williams, and Zumbrun. For large-amplitude layers, it may be efficiently checked numerically, as done in the one-dimensional case by Costanzino, Humpherys, Nguyen, and Zumbrun.
Iron and Manganese Pyrophosphates as Cathodes for Lithium-Ion Batteries

The mixed-metal phases, (Li2Mn1−yFeyP2O7, 0 ≤ y ≤ 1), were synthesized using a “wet method”, and found to form a solid solution in the P21/a space group. Both thermogravimetric analysis and magnetic susceptibility measurements confirm the 2+ oxidation state for both the Mn and Fe. The electrochemical capacity improves as the Fe concentration increases, as do the intensities of the redox peaks of the cyclic voltammogram, indicating higher lithium-ion diffusivity in the iron phase. The two Li+ ions in the three-dimensional tunnel structure of the pyrophosphate phase allows for the cycling of more than one lithium per redox center. Cyclic voltammograms show a second oxidation peak at ∼5 V and ∼5.3 V, indicative of the extraction of the second lithium ion, in agreement with ab initio computation predictions. Thus, electrochemical capacities exceeding 200 Ah/kg may be achieved if a stable electrolyte is found.
High Bids and Broke Winners

Abstract This paper analyzes auctions where budget-constrained bidders have options to declare bankruptcy. It predicts a bidding equilibrium that changes discontinuously in a borrowing rate available to bidders. When the borrowing rate is above a threshold, high-budget bidders win, and the likelihood of bankruptcy is low. When the borrowing rate is below the threshold, the winner is the most budget-constrained bidder and is most likely to declare bankruptcy. This result explains the “high bids and broke winners” anomaly in the C-Block FCC spectrum auction. Based on its equilibrium analysis, the paper proves that a seller can profit from offering to finance the highest bidder at a below-market interest rate, even with default risk. Journal of Economic Literature Classification Numbers: D44, D45, D82, G33, L96.
Diastereoselective Magnesium Halide-Catalyzed anti-Aldol Reactions of Chiral N-Acyloxazolidinones

A chiral auxilliary-based direct aldol reaction is reported. The reactions are catalytic in magnesium salts and are facilitated by silylation with chlorotrimethylsilane. The adducts isolated are in high diastereoselectivity (up to 32:1 dr) and favor the anti-aldol diastereomer B. Reactions are operationally simple and can be run under ambient atmosphere without rigorous exclusion of water. Many of the adducts are highly crystalline and a single diastereomer can be isolated without chromatography.
A note on lattice-face polytopes and their Ehrhart polynomials

We give a new definition of lattice-face polytopes by removing an unnecessary restriction in the paper "Ehrhart polynomials of lattice-face polytopes", and show that with the new definition, the Ehrhart polynomial of a lattice-face polytope still has the property that each coefficient is the normalized volume of a projection of the original polytope. Furthermore, we show that the new family of lattice-face polytopes contains all possible combinatorial types of rational polytopes.
Thiazolylalanine-derived catalysts for enantioselective intermolecular aldehyde-imine cross-couplings.

Catalytic asymmetric cross-coupling reactions between aldehydes and N-acylimines have been discovered that employ thiazolylalanine derivatives as catalysts. Alkylation of the thiazolyl moiety, foll...
On a co-induction question of Kechris

This note answers a question of Kechris: if H < G is a normal subgroup of a countable group G, H has property MD and G/H is amenable and residually finite, then G also has property MD. Under the same hypothesis we prove that for any action a of G, if b is a free action of G/H, and bG is the induced action of G, then CIndHG(a|H) × bG weakly contains a. Moreover, if H < G is any subgroup of a countable group G, and the action of G on G/H is amenable, then CIndHG(a|H) weakly contains a whenever a is a Gaussian action.
Task Difficulty and Life Changes Among Stroke Family Caregivers: Relationship to Depressive Symptoms

Abstract Objectives To investigate differences in stroke caregiver task difficulty and life changes based on level of caregiver depressive symptoms, and to estimate probabilities among task difficulty and life change items. Design Descriptive analysis of baseline data from an ongoing stroke caregiver intervention trial. Setting Hospitals and rehabilitation facilities. Participants Caregivers (N=242; 78.6% women; 47.7% spouses; 71.8% white; mean age, 54.2±12.1y) caring for stroke survivors within 8 weeks of discharge to home. Interventions Not applicable. Main Outcome Measures Baseline measures for task difficulty (Oberst Caregiving Burden Scale) and life changes (Bakas Caregiving Outcomes Scale) were compared based on level of depressive symptoms (Patient Health Questionnaire-9 [PHQ-9] scores Results Caregivers with mild to severe depressive symptoms have greater difficulty with tasks and worse life changes than those with no depressive symptoms ( P Conclusions Findings underscore the importance of depressive symptom screening for stroke caregivers during or shortly after discharge. Assisting caregivers with depressive symptoms to arrange for respite care and addressing negative physical and psychological changes may be priority areas for future interventions.
Nanophotonic Structures for Extreme Nonlinearities On-Chip

We show unprecedented strong nonlinear response from high confinement nanophotonic waveguides from the NIR to the Mid IR spectral range, by controlling the dispersion and the effective nonlinearities though novel nanofabrication techniques and novel materials.
QoS-Guaranteed Path Selection Algorithm for Service Composition

In this paper, QoS-guaranteed path selection algorithm for service composition is described. A heuristic algorithm, K-closest pruning (KCP), is used to solve the problem of multi-constraint service path selection for SON in polynomial time. The main feature of this algorithm is that the path selected by this algorithm meets all the QoS requirements specified by the user/application. The main idea in this approach is to leverage network proximity information to reduce search space, i.e. to reduce the number of qualified overlay nodes/links, for service path selection for a given request. This paper demonstrates the two distinct objectives reuse and load balancing and their use in modifying the path selection of KCP algorithm to achieve the objectives with affecting performance of KCP algorithm
A Magnetic Model with a Possible Chern-Simons Phase

An elementary family of local Hamiltonians H◦,l, l = 1,2,3, . . ., is described for a 2−dimensional quantum mechanical system of spin = 1 particles. On the torus, the ground state space G◦,l is (log) extensively degenerate but should collapse under “perturbation” to an anyonic system with a complete mathematical description: the quantum double of the SO(3)−Chern-Simons modular functor at q = e 2πi/l+2 which we call DEl. The Hamiltonian H◦,l defines a quantum loop gas. We argue that for l = 1 and 2, G◦,l is unstable and the collapse to Gǫ,l ∼ DEl can occur truly by perturbation. For l ≥ 3, G◦,l is stable and in this case finding Gǫ,l ∼ DEl must require either ǫ > ǫl > 0, help from finite system size, surface roughening (see section 3), or some other trick, hence the initial use of quotes “ ”. A hypothetical phase diagram is included in the introduction. The effect of perturbation is studied algebraically: the ground state space G◦,l of H◦,l is described as a surface algebra and our ansatz is that perturbation should respect this structure yielding a perturbed ground state Gǫ,l described by a quotient algebra. By classification, this implies Gǫ,l ∼ DEl. The fundamental point is that nonlinear
Non-reductive Homogeneous Pseudo-Riemannian Manifolds of Dimension Four

A method, due to Elie Cartan, is used to give an algebraic classification of the non-reductive homogeneous pseudo-Riemannian manifolds of dimension four. Only one case with Lorentz signature can be Einstein without having constant curvature, and two cases with (2, 2) signature are Einstein of which one is Ricci-flat. If a four-dimensional non-reductive homogeneous pseudo-Riemannian manifold is simply connected, then it is shown to be diffeomorphic to . All metrics for the simply connected non-reductive Einstein spaces are given explicitly. There are no non-reductive pseudo-Riemannian homogeneous spaces of dimension two and none of dimension three with connected isotropy subgroup.
The Effect of Environment on the X-Ray Emission from Early-Type Galaxies

In order to further our understanding of the phenomena of X-ray emission from early-type galaxies, we obtained an optically flux-limited sample of 34 elliptical and S0 galaxies, observed with high and low angular resolution detectors on ROSAT. Our previous analysis of this sample suggested that the most X-ray-luminous galaxies were in rich environments. Here we investigate environmental influences quantitatively and find a positive correlation between LX/LB and the local galaxy density. Since the local galaxy density is usually related to the density of hot intergalactic gas, we suggest that this correlation occurs because the X-ray luminosity is enhanced, either through accretion of the intergalactic gas or because the ambient medium stifles galactic winds. When the ambient medium is unimportant, partial or global galactic winds can occur, reducing LX/LB. These effects lead to the large observed dispersion in LX at fixed LB. We discuss details of the data processing not previously presented, and examine the dependence of LX on the choice of outer source radius and background location. We also compare the temperature deduced for these galaxies from different analyses of ROSAT and ASCA data. The ASCA and ROSAT temperatures are found to be similar, provided that the same metallicities and Galactic absorption columns are used.
Surface retarded modes in multilayered structures: Parallel magnetization.

The wave dispersion relations of the mixed polariton-photon modes propagating along the surface of a semi-infinite layered structure consisting of alternating magnetic and nonmagnetic films are calculated. The magnetic films are magnetized to saturation by an external field parallel to the film plane and perpendicular to the wave propagation direction. Three different types of surface modes are found and discussed. The surface-surface-type and (lower) surface-bulk-type modes can exist in a general layered structure which, when propagating in the positive k direction, corresponds in magnetostatic limit to those surface modes found by Camley et al. For negative k propagation of surface-surface-type modes, different functional forms are approached in the magnetostatic limit depending on the value of permittivity of the nonmagnetic layers. A new type of surface waves, the upper surface-bulk-type modes, which do not exist in the magnetostatic regime, can arise only if the (optical) permeability of the magnetic medium is larger than the permittivity of the nonmagnetic medium. This is a situation similar to the occurrence of those negatively propagating surface modes in a single semi-infinite gyromagnetic medium as discussed by Hartstein. Among the three types of surface modes only the surface-surface-type modes show a great deal of nonreciprocity with respect to wave propagation directions.
Mirror symmetry, Langlands duality, and the Hitchin system

Among the major mathematical approaches to mirror symmetry are those of Batyrev-Borisov and Strominger-Yau-Zaslow (SYZ). The first is explicit and amenable to computation but is not clearly related to the physical motivation; the second is the opposite. Furthermore, it is far from obvious that mirror partners in one sense will also be mirror partners in the other. This paper concerns a class of examples that can be shown to satisfy the requirements of SYZ, but whose Hodge numbers are also equal. This provides significant evidence in support of SYZ. Moreover, the examples are of great interest in their own right: they are spaces of flat SLr-connections on a smooth curve. The mirror is the corresponding space for the Langlands dual group PGLr. These examples therefore throw a bridge from mirror symmetry to the duality theory of Lie groups and, more broadly, to the geometric Langlands program.
Diagnostic calculations of the circulation in the Martian atmosphere

The circulation of the Martian atmosphere during late southern summer is derived from atmospheric temperature and dust distributions retrieved from a subset of the Mariner 9 infrared interferometer spectrometer (IRIS) thermal emission spectra (LS = 343-348 deg) (Santee and Crisp, 1933). Zonal-mean zonal winds are calculated by assuming gradient wind balance and zero surface zonal wind. Both hemispheres have intense midlatitude westerly jets with velocities of 80-90 m/s near 50 km; in the southern tropics the winds are easterly with velocities of 40 m/s near 50 km. The net effect of the zonal-mean meridional circulation and large-scale waves can be approximated by the diabatic ciculation, which is defined from the atmospheric thermal structure and net radiative heating rates. The radiative transfer model described by Crisp (1990) and Santee (1993) is used to compute solar heating and thermal cooling rates from diurnal averages of the retrieved IRIS temperature and dust distributions. At pressures below 4 mbar, there are large net radiative heating rates (up to 5 K/d) in the equatorial region and large net radiative cooling rates (up to 12 K/d) in the polar regions. These net radiative heating rates are used in a diagnostic stream function model which solves for the meridonal and vertical components of the diabatic circulation simultaneously. We find a two cell circulation, with rising motion over the equator, poleward flow in both hemispheres, sinking motion over both polar regions, and return flow in the lowest atmospheric levels. The maximum poleward velocity is 3 m/s in the tropics at approximately 55 km altitude, and the maximum vertical velocity is 2.5 cm/s downward over the north pole at approximately 60 km altitude. If these large transport rates are sustained for an entire season, the Martian atmosphere above the 1-mbar level is overturned in about 38 days. This diabatic circulation is qualitatively similar to the terrestial diabatic circulation at the comparable season, but is more vigorous.
A Coding Theorem for a Class of Stationary Channels With Feedback

A coding theorem is proved for a class of stationary channels with feedback in which the output Yn = f(Xn-m n, Zn-m n) is the function of the current and past m symbols from the channel input Xn and the stationary ergodic channel noise Zn. In particular, it is shown that the feedback capacity is equal to limnrarr infin supp(x n ||y n-1 ) 1/n I(Xn rarr Yn) where I(Xn rarr Yn) = Sigmai=1 n I(Xi; Yi|Yi-1) denotes the Massey directed information from the channel input to the output, and the supremum is taken over all causally conditioned distributions p(xn||yn-1) = Pii=1 n p(xi|xi-1,yi-1). The main ideas of the proof are a classical application of the Shannon strategy for coding with side information and a new elementary coding technique for the given channel model without feedback, which is in a sense dual to Gallager's lossy coding of stationary ergodic sources. A similar approach gives a simple alternative proof of coding theorems for finite state channels by Yang-Kavcic-Tatikonda, Chen-Berger, and Permuter-Weissman-Goldsmith.
The use of quick prototypes in the secure military message systems project

This paper describes the role of quick prototyping in the Secure Military Message Systems project. The issues that are being explored with quick prototyping are identified. To date, a small prototype message system written in Franz Lisp has been implemented on a Vax 11/780. The guidelines observed and the lessons learned in constructing the prototype are discussed.
Research with High-Power Short-Wavelength Lasers

Three high-temperature, high-density experments were conducted recently with the 10-terawatt, short-wavelength Novette laser system at the Lawrence Livermore National Laboratory. The experiments demonstrated successful solutions to problems that arose during previous laser-plasma interaction experiments with long-wavelength (greater than 1 micrometer) lasers: (i) large-scale plasmas, with dimensions approaching those needed for high-gain inertial fusion targets, were produced in which potentially deleterious laser-plasma instabilities were collisionally damped; (ii) deuterium-tritium fuel was imploded to a density of 20 grams per cubic centimeter and a pressure of 10(10) atmospheres under the improved laser conditions, and compression conditions (preheating and pressure) were consistent with code calculations that predict efficient (high-gain) burn of a large thermonuclear fuel mass when driven with a large, short-wavelength laser; and (iii) soft x-rays were amplified by a factor of 700 by stimulated emission at 206 and 209 angstroms (62 electron volts) from selenium ions in a laser-generated plasma. These small, short-pulse x-ray sources are 10(10) to 10(11) times brighter than the most powerful x-ray generators and synchrotron sources available today. The plasma conditions for these experiments were made possible by advances in Nd:glass laser technology, in techniques to generate efficiently its short-wavelength harmonics at 0.53, 0.35, and 0.26 micrometers, and in diagnostic and computational modeling.
The Eddington Limit in Cosmic Rays: An Explanation for the Observed Faintness of Starbursting Galaxies

We show that the luminosity of a star-forming galaxy is capped by the production and subsequent expulsion of cosmic rays from its interstellar medium. By defining an Eddington luminosity in cosmic rays, we show that the star formation rate of a given galaxy is limited by its mass content and the cosmic-ray mean free path. When the cosmic-ray luminosity and pressure reach a critical value as a result of vigorous star formation, hydrostatic balance is lost, a galactic-scale cosmic-ray-driven wind develops, and star formation is choked off. Cosmic-ray pressure driven winds are likely to produce wind velocities in proportion to and significantly in excess of the galactic escape velocity. It is possible that cosmic-ray feedback results in the Faber-Jackson relation for a plausible set of input parameters that describe cosmic-ray production and transport, which are calibrated by observations of the Milky Way's interstellar cosmic rays as well as other nearby galaxies.
Gender and Global Lawyering: Where are the Women?

The dual forces of globalization and support for diversity in the legal profession are responsible for significant growth among U.S. law firms. Both women lawyers and those educated outside of the U.S. have been important elements facilitating the global trajectories of U.S. firms, but the interaction between the two has not been the subject of substantial research. We address this gap by drawing on an original dataset of lawyer biographies, and consider whether career strategies that involve the international mobility of lawyers are equally powerful for women and men. Our research suggests that globalization of large firm practice has not erased gender inequality, and, in fact, may have reinforced and strengthened existing gender disparities.