cssi/SciSciGPT-SciSciNet huggingface dataset:
VLSI and intelligent transducers

Abstract A review of VLSI (very large-scale integration) technology is presented to discuss new technology, materials, devices and system organization. Advances in VLSI technology may have impact on sensor research in that (a) novel processes and device designs developed in VLSI may provide the means to realize improved semiconductor sensors and processing circuits; and (b) the integration of sensors with signal-processing and decision-making circuits makes the complex intelligent sensor possible. Intelligent sensors can be grouped into (a) sensors with processing circuits and active devices to improve signal-to-noise ratio; (b) sensors with electronic circuits for signal processing and decision making to convert signals to various forms ready for further manipulation. Functions of intelligent transduces are discussed with examples. Interaction between VLSI and transducer design as well as problems in incorporating VLSI technology into sensor research are discussed. Problem areas in materials, process compatibility and packaging are outlined.
Transition states for surface-catalyzed chemistry.

Fluorine substituent effects have been used to probe the nature of the transition states for the several elementary reaction steps occurring on metal surfaces. The reactions described include β-hydrogen elimination in adsorbed alkoxide and alkyl groups, coupling of alkyl groups, and dehalogenation of alkyl chloride and iodides. The substituent effect method can provide a connection between heterogeneous catalysis, surface science, and computational molecular simulation of surface reactions.
Intersectoral Labor Mobility and the Growth of the Service Sector

One of the most striking changes in the U.S. economy over the past 50 years has been the growth in the service sector. Between 1950 and 2000, service-sector employment grew from 57 to 75 percent of total employment. However, over this time, the real hourly wage in the service sector grew only slightly faster than in the goods sector. In this paper, we assess whether or not the essential constancy of the relative wage implies that individuals face small costs of switching sectors, and we quantify the relative importance of labor supply and demand factors in the growth of the service sector. We specify and estimate a two-sector labor market equilibrium model that allows us to address these empirical issues in a unified framework. Our estimates imply that there are large mobility costs: output in both sectors would have been double their current levels if these mobility costs had been zero. In addition, we find that demand-side factors, that is, technological change and movements in product and capital prices, were responsible for the growth of the service sector.
Parasitic capacitance cancellation in filter inductors

This paper introduces a technique for improving the high-frequency performance of filter inductors and common-mode chokes by cancelling out the effects of parasitic capacitance. This technique uses additional passive components to inject a compensation current that cancels the parasitic current, thereby improving high-frequency filtering performance. Two implementation approaches for this technique are introduced. The first implementation achieves cancellation using an additional small winding on the filter inductor and a small capacitor. This approach is effective where very high coupling of the windings can be achieved or where only moderate performance improvements are required. The second implementation utilizes a small radio frequency transformer in parallel with the filter inductor to inject cancellation currents from the compensation capacitor. This technique requires an additional component (the transformer), but can provide a high degree of cancellation. Experimental results confirm the theory in both implementations.
The Reaction of Organoboranes with Trimethylsilyl Azide in a Neutral Medium: Synthesis of Primary Amines

Abstract A facile method for the preparation of primary amines using trimethylsilyl azide and trialXyl-boranes in a neutral protic solvent is described.
A structured flexible transit system for low demand areas

Abstract Public transit structure is traditionally designed to contain fixed bus routes and predetermined bus stations. This paper presents an alternative flexible-route transit system, in which each bus is allowed to travel across a predetermined area to serve passengers, while these bus service areas collectively form a hybrid “grand” structure that resembles hub-and-spoke and grid networks. We analyze the agency and user cost components of this proposed system in idealized square cities and seek the optimum network layout, service area of each bus, and bus headway, to minimize the total system cost. We compare the performance of the proposed transit system with those of comparable systems (e.g., fixed-route transit network and taxi service), and show how each system is advantageous under certain passenger demand levels. It is found out that under low-to-moderate demand levels, the proposed flexible-route system tends to have the lowest system cost.
Semiconductor/molecule transport junctions: An analytic form for the self-energies

We have derived an approximate analytic expression for the spectral density of a simple model of a semiconductor/molecule junction. The semiconductor is considered as a tight-binding one-dimensional chain with periodic boundary conditions, and either bond or site-energy alternation, to mimic a two-band system. Using the simplest representation for an atomic or molecular site we obtain a spectral density whose main physical and mathematical features are independent of the alternation pattern. Our model can be applied to the description of transport properties in many complex junctions. Here, we have explored its simplest consequences in the calculation of the transmission coefficient for a junction consisting of a semiconductor electrode, a molecular site and a metal electrode.
Chrysochlamic acid, a new diterpenoid-substituted quinol from Chrysochlamys ulei that inhibits DNA polymerase β

Chrysochlamic acid (1), a new DNA polymerase β inhibitor having an IC50 of 4.3 µM, has been isolated from Chrysochlamys ulei through bioassay-guided fractionation; it is the first example of a prenyl m-methylhydroquinone occurring in a higher terrestrial plant.
Limitations of equation-based congestion control

We study limitations of an equation-based congestion control protocol, called TCP-Friendly Rate Control (TFRC). It examines how the three main factors that determine TFRC throughput, namely, the TCP-friendly equation, loss event rate estimation, and delay estimation, can influence the long-term throughput imbalance between TFRC and TCP. Especially, we show that different sending rates of competing flows cause these flows to experience different loss event rates. There are several fundamental reasons why TFRC and TCP flows have different average sending rates, from the first place. Earlier work shows that the convexity of the TCP-friendly equation used in TFRC causes the sending rate difference. We report two additional reasons in this paper: 1) the convexity of 1/x where x is a loss event period and 2) different retransmission timeout period (RTO) estimations of TCP and TFRC. These factors can be the reasons for TCP and TFRC to experience initially different sending rates. But we find that the loss event rate difference due to the differing sending rates greatly amplifies the initial throughput difference; in some extreme cases, TFRC uses around 20 times more, or sometimes 10 times less, bandwidth than TCP. Despite these factors influencing the throughput difference, we also find that simple heuristics can greatly mitigate the problem.
Energetic constraints on spectral distortions of the microwave background

The energetic constraints on mechanisms for producing the spectral distortion of the microwave background claimed by Matsumoto et al., (1988) are investigated in the light of the new upper bounds on the cosmological baryon density derived by Kawano et al., (1988) from primordial nucleosynthesis. The thermal emission from dust heated by stars at large redshift and Compton scattering by a hot intergalactic medium heated by supernova explosions are considered, and it is concluded that both mechanisms fail on energetic grounds if they rely on stars formed with the same mass function as is observed in the solar neighborhood.
White-Light Optical Vortex Coronagraph

An optical vortex coronagraph with a vortex lens provides high contrast imaging over a narrow band of wavelengths. Here we report broadband experimental results by use of a vortex hologram and a dispersion-compensating grating.
Structural and magnetic properties of bis(ethanolammonium)hexahalodicuprate(II) salts: Copper(II) halide dimers with a square-pyramidal type distortion

Abstract The compounds (C 4 H 16 N 2 O 2 )Cu 2 Cl 6 and (C 4 H 16 N 2 O 2 )Cu 2 Br 6 have been synthesized and their crystal structures determined. EPR and magnetic susceptibility measurements were made. The crystals of both compounds are triclinic, space group P 1 with a = 6.077(1), b =8.068(2), c =8.455(2) A, α=67.99(2), β=79.90(2), γ=78.77(2)°, Z =2, and D calc = 2.08 g/cm 3 for the chloride salt, and a =6.418(2), b =8.262(2), c =8.764(2) A, α=68.17(2), β=80.12(2), γ=78.47(2)°, Z =2, and D calc =2.88 for the bromide salt. The structures, solved by direct methods and refined by least-squares calculations to R =0.036 (chloride) and R =0.049 (bromide), consist of nearly planar Cu 2 X 6 2− dimers stacked to form infinite chains. The coordination of the copper atoms may be described as distorted square pyramidal with an ethanolammonium oxygen semi- coordinated to the sixth coordination site for each copper atom. Both compounds exhibit predominantly antiferromagnetic exchange interactions. The bromide salt exhibits a intradimer singlet-triplet energy splitting of J / k =−64 K and a interdimer splitting of J ′/ k =−21 K, while for the chloride J / k =−6 K and J ′/ k =−6 K is deduced. A comparison with the magnetic behavior of other Cu 2 - X 6 2− dimers is given.
Do African countries pay more for imports

The debt crisis and declining living standards require careful husbanding of critically scarce foreign exchange in most African countries. But economic theory suggests that smaller countries, which import from only a few international suppliers and cannot support competitive markets and infrastructure, would be likely to pay more, rather than less for imports. Analysis of import unit values for 1962-87 shows that the twenty African former French colonies paid a price premium of 20-30 percent on average over other imports for iron and steel imports from France. The losses associated with these adverse prices totalled approximately 2 billion dollars by 1987. They study also finds that similar price premia (of 20-30 percent) were paid by former Beligian, British, and Portuguese colonies in Africa for imports of these products from their former rulers.
Me, you, and us: Distinguishing “egoism,” “altruism,” and “groupism”

Attention is drawn to significant distinctions implicit in our everyday non-technical conceptual scheme. Three forms of motivation are distinguished: “egoism,” “altruism,” and “groupism.” The relationship between them is considered. It is argued that groupish motives (as argued here) are not of themselves either altruistic or selfish ones in the relevant senses.
A self-calibration approach to extrinsic parameter estimation of stereo cameras

Abstract A self-calibration technique is proposed in this paper to estimate extrinsic parameters of a stero camera system. This technique does not require external 3D measurements of precision calibration points. Furthermore, it is conceptually simple and easy to implement. It has applications in such areas as autonomous vehicle navigation, robotics and computer vision. The proposed approach relies solely on distance measurements of a fixed-length object, say a stick. While the object is moved in the 3D space, the image coordinates of the end points of the object are extracted from the image sequence. A cost function that relates the unknown parameters to the measurement residuals is formulated. A nonlinear least squares algorithm is then applied to compute the parameters by minimizing the cost function, using the measured image coordinates and the known length of the object. Simulation studies in this papers answer questions such as the number of iterations needed for the algorithm to converge, the number of measurements needed for a robust estimation, and noise sensitivities of the algorithm.
The stereospecific preparation of fluorinated vinyl zinc reagents from polyfluorinated vinyl iodides or bromides and zinc metal

Abstract Fluorinated vinyl zinc reagents can be prepared readily via the direct reaction of polyfluorinated vinyl iodides or bromides with zinc metal in a variety of solvents, such as DMF, DMAc, THF, glymes, and acetonitrile. The formation of symmetrical dienes via coupling of the vinyl halide is not observed. With E and Z -vinyl subtrates total retention of configuration is observed in the formation of the zinc reagents, and in subsequent functionalization reactions. The excellent thermal stability of these zinc reagents at or above room temperature, and the possibility of employing a variety of solvents allow subsequent reactions to be easily tailored to meet experimental requirements. Therefore, this approach provides a facile, easily scaled up, stereospecific, one-pot procedure to these stable vinyl organometallic reagents.
Calix[4]arene-bis(dibenzocrown-6-ethers) with one proton-ionizable group

Abstract Two 1,3-alternate calix[4]arene-biscrowns with one proton-ionizable group and two dibenzocrown-6-ether units are synthesized. The compounds exhibit high Cs + extraction efficiency and selectivity. Cs + /Na + and Cs + /K + selectivities for the new N -(trifluoromethylsulfonyl)carbamoyl-substituted calix[4]arene-bis(dibenzocrown-6) are found to be higher than those for an analog with no benzo group substituents in the crown ether units.
Cross-Coupling of sp3 C−H Bonds and Alkenes: Catalytic Cyclization of Alkene−Amide Substrates

We herein present a new oxidative cyclization of alkene−amide substrates under neutral and catalytic conditions. This overall transformation requires tandem sp3 C−H activation (at the position adjacent to the amide nitrogen) and C−C bond formation. Specifically, pyrrolidine 1 was converted to pyrrolizidinone 3 and indolizidinone 4 in 66% and 17% yield, respectively, in the presence of [Ir(coe)2Cl]2, the carbene ligand IPr (1:1 metal/ligand ratio, 5−10 mol % of Ir), and the hydrogen acceptor (NBE or TBE, 3−10 equiv). The results presented in this study suggest that complex 10 [IPr−Ir(Cl)(substrate)] is the key intermediate in the catalytic cycle. On the mechanistic front, the key advance was the ability to facilitate C−H activation and alkene insertion in tandem, and in preference to β-hydride elimination, in the context of amide substrates. With respect to complex synthesis, catalytic and neutral conditions of this method unlock new exciting opportunities as illustrated by regioselective cyclization of th...
Abelian and nonabelian vector field effective actions from string field theory

The leading terms in the tree-level effective action for the massless fields of the bosonic open string are calculated by integrating out all massive fields in Witten's cubic string field theory. In both the abelian and nonabelian theories, field redefinitions make it possible to express the effective action in terms of the conventional field strength. The resulting actions reproduce the leading terms in the abelian and nonabelian Born-Infeld theories. In principle this method can be used to systematically determine all terms in the abelian and nonabelian actions, including all higher-order derivative terms.
TECHNOLOGY ENABLING INNOVATION IN ONLINE GRADUATE MANAGEMENT EDUCATION

It has been approximately twenty-five years since the Internet became available for public use and slightly over ten years since the World Wide Web became readily accessible. In this paper, we examine innovations in graduate management educational delivery methods that have increased the quality of distance education by investigating the literature surrounding distance education with a focus on four major concepts and their association with modern education technologies. Our exploration involves a comparison of an innovative, parsimonious, online educational model with other methods of graduate management education especially for adult management students. Through this model, we focus on four major concepts that can have a significant impact on management education quality. The first two concepts include dialogue and structure that have been used to describe and assess the quality of distance education programs. The second two concepts comprise students' ability to access courses and the flexibility that students have relative to their participation in courses. We note that these four factors can impact the delivery, content, innovativeness, and quality of graduate management education programs. We review existing models of distance education and note how each model relates to each of these four factors. We then suggest how the design and delivery of online education programs can be improved with a greater understanding of these four concepts in addition to their relationship with recently developed web-based technologies. Finally, we discuss several issues surrounding the administration of web-based education programs and identify several questions that call for further investigation.
Nonequilibrium aspects of quantum field theory

Abstract We have developed a method for extracting equilibrium observables from non-equilibrium simulations by rapidly changing the temperature and recording the subsequent evolution of the Polyakov loop. Both nucleation and spinodal decomposition are observed to occur. In the latter case the Polyakov loop correlation function shows exponential growth for wavenumbers less than or equal to the critical wavenumber k c . We have constructed the bare as well as the effective potential for the Polyakov loop, from which k c and m D / k c can be extracted as a function of temperature. The shift from spinodal decomposition to nucleation as the dominant equilibration mechanism occurs at the spinodal temperature that separates these two regimes.
Compact tori for alternate fuel fusion

Abstract A D-T burn dynamic experiment using a scaled-up field-reversed theta-pinch device is proposed as a first step towards demonstration of a D-3He burn. The feasibility of such an experiment is based on a loss-cone-like confinement scaling described here plus the concept of using combined pellet and neutral-beam injection to heat the plasma, build-up its density, and damp the m = 2 instability. The potential extension to a D-3He reactor is also discussed.
The role of the discriminant factor in the assessment and treatment of alcoholic hepatitis.

Goals To evaluate the role of the discriminant factor in predicting mortality and deciding on treatment in acute alcoholic hepatitis. Background Current guidelines on the treatment of alcoholic hepatitis restrict the use of corticosteroids to patients with discriminant factor > 32 (severe disease) because of the toxicity of steroids. Less toxic forms of therapy, such as proxyphylline, may have a role in patients with lower discriminant factor, if mortality without therapy is common. Study We performed a 5-year retrospective analysis comparing the outcomes of patients with mild and severe alcoholic hepatitis. Receiver operator characteristic curves were used to study the accuracy of the discriminant factor to predict short-term mortality. Results Among the 41 patients with severe alcoholic hepatitis (discriminant factor > 32) and 48 with mild alcoholic hepatitis, 16 (39%) and 8 (16.7%), respectively, died within 28 days of admission. Only 11 (32%) actually received corticosteroid therapy. The sensitivity and specificity of the discriminant factor in predicting mortality was 66.7% and 61.5%, respectively. A receiver operator characteristic curve of the discriminant factor gave the optimal value for the discriminant factor as 33, with the area under the curve being 0.666 (P = 0.0078; 95% CI = 0.531-0.801). Conclusions Using the value of around 32 maximizes sensitivity and specificity of the discriminant factor in predicting mortality in alcoholic hepatitis. However, there is a high mortality in patients with alcoholic hepatitis and a discriminant factor less than 32. Alternative effective agents should be considered in patients with milder alcoholic hepatitis.
Near-optimal hashing algorithms for approximate nearest neighbor in high dimensions

In this article, we give an overview of efficient algorithms for the approximate and exact nearest neighbor problem. The goal is to preprocess a dataset of objects (e.g., images) so that later, given a new query object, one can quickly return the dataset object that is most similar to the query. The problem is of significant interest in a wide variety of areas.
Quickest Detection with Discretely Controlled Observations

Abstract We study a continuous-time Bayesian quickest detection problem in which observation times are a scarce resource. The agent, limited to making a finite number of discrete observations, must adaptively decide his observation strategy to minimize detection delay and the probability of false alarm. Under two different models of observation rights, we establish the existence of optimal strategies and formulate an algorithmic approach to the problem via jump operators. We describe algorithms for these problems and illustrate them with some numerical results. As the number of observation rights tends to infinity, we also show convergence to the classical continuous observation problem of Shiryaev.
The home reckoner: a scenario on the home use of computers

Certain similarities between the "H.R." set and General Purpose computers currently marketed, would indicate that the community of people engaged in the various phases of that business might be interested in a technically oriented description of the appliance in question, and its potential role in the home.
Synthesis of γ,δ-Unsaturated Glycolic Acids via Sequenced Brook and Ireland−Claisen Rearrangements

Organozinc, -magnesium, and -lithium nucleophiles initiate a Brook/Ireland−Claisen rearrangement sequence of allylic silyl glyoxylates resulting in the formation of γ,δ-unsaturated α-silyloxy acids.
Conjugated systems derived from piperazine‐2,5‐dione

The preparation of mono- and of symmetrical and unsymmetrical bis-ylidine derivatives of piperazine- 2,5-dione is described. The uv-visible absorption of the products is correlated with acceptor/donor character of the substituents.
Marriage and Socioeconomic Change in Contemporary Indonesia

This study investigates the relationship between economic trends and entry into marriage in a rapidly developing setting. We examine Indonesian marriage in the 1990's, a decade of substantial economic growth followed by a sudden financial collapse in 1998. We use discrete-time hazard models to analyze information on 4,078 women and 4,496 men from the Indonesia Family Life Survey. While previous research has shown that marriages may be postponed after economic downturn, we find no evidence of such delays at the national level following the 1998 financial crisis. In contrast, we use regional wage rate data to show that entry into marriage is inversely related to economic growth throughout the decade for all women and for men from lower socioeconomic strata.
Tachyon instability and Kondo type models

Abstract We consider compactifications of bosonic open string theory on maximal tori of various simple Lie algebras with a specific background coupled to the string boundaries. The resulting worldsheet CFT is a free theory perturbed by a boundary term that is marginal but not truly marginal. We assume that the theory flows to a nontrivial infrared fixed point that is similar to the one in Kondo model. This RG flow reflects the tachyon instability of the bosonic string vacuum. At the fixed point we calculate the new spectrum and some of the Green's functions. We find that in some of the sectors the tachyon mass gets lifted that can be interpreted as a result of switching on appropriate Wilson lines. Various compactifications and patterns of flows are investigated.
Distributed approximation algorithms for weighted shortest paths

A distributed network is modeled by a graph having n nodes (processors) and diameter D. We study the time complexity of approximating weighted (undirected) shortest paths on distributed networks with a O (log n) bandwidth restriction on edges (the standard synchronous CONGEST model). The question whether approximation algorithms help speed up the shortest paths and distance computation (more precisely distance computation) was raised since at least 2004 by Elkin (SIGACT News 2004). The unweighted case of this problem is well-understood while its weighted counterpart is fundamental problem in the area of distributed approximation algorithms and remains widely open. We present new algorithms for computing both single-source shortest paths (SSSP) and all-pairs shortest paths (APSP) in the weighted case. Our main result is an algorithm for SSSP. Previous results are the classic O(n)-time Bellman-Ford algorithm and an O(n1/2+1/2k + D)-time (8k⌈log(k + 1)⌉ --1)-approximation algorithm, for any integer k ≥ 1, which follows from the result of Lenzen and Patt-Shamir (STOC 2013). (Note that Lenzen and Patt-Shamir in fact solve a harder problem, and we use O(·) to hide the O(poly log n) term.) We present an O (n1/2D1/4 + D)-time (1 + o(1))-approximation algorithm for SSSP. This algorithm is sublinear-time as long as D is sublinear, thus yielding a sublinear-time algorithm with almost optimal solution. When D is small, our running time matches the lower bound of Ω(n1/2 + D) by Das Sarma et al. (SICOMP 2012), which holds even when D=Θ(log n), up to a poly log n factor. As a by-product of our technique, we obtain a simple O (n)-time (1+ o(1))-approximation algorithm for APSP, improving the previous O(n)-time O(1)-approximation algorithm following from the results of Lenzen and Patt-Shamir. We also prove a matching lower bound. Our techniques also yield an O(n1/2) time algorithm on fully-connected networks, which guarantees an exact solution for SSSP and a (2+ o(1))-approximate solution for APSP. All our algorithms rely on two new simple tools: light-weight algorithm for bounded-hop SSSP and shortest-path diameter reduction via shortcuts. These tools might be of an independent interest and useful in designing other distributed algorithms.
Alkane-modified short polyethyleneimine for siRNA delivery.

RNA interference (RNAi) is a highly specific gene-silencing mechanism triggered by small interfering RNA (siRNA). Effective intracellular delivery requires the development of potent siRNA carriers. Here, we describe the synthesis and screening of a series of siRNA delivery materials. Short polyethyleneimine (PEI, Mw 600) was selected as a cationic backbone to which lipid tails were conjugated at various levels of saturation. In solution these polymer–lipid hybrids self-assemble to form nanoparticles capable of complexing siRNA. The complexes silence genes specifically and with low cytotoxicity. The efficiency of gene knockdown increased as the number of lipid tails conjugated to the PEI backbone increased. This is explained by reducing the binding affinity between the siRNA strands to the complex, thereby enabling siRNA release after cellular internalization. These results highlight the importance of complexation strength when designing siRNA delivery materials.
SETI target selection.

Abstract The NASA High Resolution Microwave Survey consists of two complementary elements: a Sky Survey of the entire sky to a moderate level of sensitivity; and a Targeted Search of nearby stars, one at a time, to a much deeper level of sensitivity. In this paper we propose strategies for target selection. We have two goals: to improve the chances of successful detection of signals from technical civilizations that inhabit planets around solar-type stars, and to minimize the chances of missing signals from unexpected sites. For the main Targeted Search survey of approximately 1000 nearby solar-type stars, we argue that the selection criteria should be heavily biased by what we know about the origin and evolution of life here on Earth. We propose that observations of stars with stellar companions orbiting near the habitable zone should be de-emphasized, because such companions would prevent the formation of habitable planets. We also propose that observations of stars younger than about three billion years should be de-emphasized in favor of older stars, because our own technical civilization took longer than three billion years to evolve here on Earth. To provide the information needed for the preparation of specific target lists, we have undertaken an inventory of a large sample of solar-type stars out to a distance of 60 pc, with the goal of characterizing the relevant astrophysical properties of these stars, especially their ages and companionship. To complement the main survey, we propose that a modest sample of the nearest stars should be observed without any selection biases whatsoever. Finally, we argue that efforts to identify stars with planetary systems should be expanded. If found, such systems should receive intensive scrutiny.
Passive tracer patchiness and particle trajectory stability in incompressible two-dimensional flows

Abstract. Particle motion is considered in incompressible two-dimensional flows consisting of a steady background gyre on which an unsteady wave-like perturbation is superimposed. A dynamical systems point of view that exploits the action-angle formalism is adopted. It is argued and demonstrated numerically that for a large class of problems one expects to observe a mixed phase space, i.e. the occurrence of "regular islands" in an otherwise "chaotic sea". This leads to patchiness in the evolution of passive tracer distributions. Also, it is argued and demonstrated numerically that particle trajectory stability is largely controlled by the background flow: trajectory instability, quantified by various measures of the "degree of chaos", increases on average with increasing , where is the angular frequency of the trajectory in the background flow and I is the action.
Investigating Some Technical Issues on Cohesive Zone Modeling of Fracture

This study investigates some technical issues related to the use of cohesive zone models (CZMs) in modeling fracture processes. These issues include: why cohesive laws of different shapes can produce similar fracture predictions; under what conditions CZM predictions have a high degree of agreement with linear elastic fracture mechanics (LEFM) analysis results; when the shape of cohesive laws becomes important in the fracture predictions; and why the opening profile along the cohesive zone length needs to be accurately predicted. Two cohesive models were used in this study to address these technical issues. They are the linear softening cohesive model and the Dugdale perfectly plastic cohesive model. Each cohesive model constitutes five cohesive laws of different maximum tractions. All cohesive laws have the same cohesive work rate (CWR) which is defined by the area under the traction-separation curve. The effects of the maximum traction on the cohesive zone length and the critical remote applied stress are investigated for both models. For a CZM to predict a fracture load similar to that obtained by an LEFM analysis, the cohesive zone length needs to be much smaller than the crack length, which reflects the small scale yielding condition requirement for LEFM analysis to be valid. For large-scale cohesive zone cases, the predicted critical remote applied stresses depend on the shape of cohesive models used and can significantly deviate from LEFM results. Furthermore, this study also reveals the importance of accurately predicting the cohesive zone profile in determining the critical remote applied load.
Tandem Reactions for Streamlining Synthesis: Enantio- and Diastereoselective One-Pot Generation of Functionalized Epoxy Alcohols

In 1980, Sharpless and Katsuki introduced the asymmetric epoxidation of prochiral allylic alcohols (the Sharpless−Katsuki asymmetric epoxidation), which enabled the rapid synthesis of highly enantioenriched epoxy alcohols. This reaction was a milestone in the development of asymmetric catalysis because it was the first highly enantioselective oxidation reaction. Furthermore, it provided access to enantioenriched allylic alcohols that are now standard starting materials in natural product synthesis. In 1981, Sharpless and co-workers made another seminal contribution by describing the kinetic resolution (KR) of racemic allylic alcohols. This work demonstrated that small-molecule catalysts could compete with enzymatic catalysts in KRs. For these pioneering works, Sharpless was awarded the 2001 Nobel Prize with Knowles and Noyori. Despite these achievements, the Sharpless KR is not an efficient method to prepare epoxy alcohols with high enantiomeric excess (ee). First, the racemic allylic alcohol must be prep...
Numerical Linear System Solving with Parametric Entries by Error Correction

We consider the problem of solving a full rank consistent linear system A(u)x = b(u) where the m x n matrix A and the m-dimensional vector b has entries that are polynomials in u over a field. We give an algorithm that computes the unique solution x = f(u)/g(u), which is a vector of rational functions, by evaluating the parameter u at distinct points. Those points ξλ where the matrix A evaluates to a matrix A(ξλ), with entries over the scalar field, of lower rank, or in the numeric setting to an ill-conditioned matrix, are not identified but accounted for by error-correcting code techniques. We also correct true errors where the evaluation at some u = ξλ results in an erroneous, possibly full rank consistent and well-conditioned scalar linear system. Our algorithm generalizes Welch/Berlekamp decoding of Reed/Solomon error correcting codes and their numeric floating point counterparts.We have implemented our algorithms with floating point arithmetic. For the determination of the exact numerator and denominator degrees and number of errors we use singular values based numeric rank computations. The arising linear systems for the error-corrected parametric solution are demonstrated to be well-conditioned even when the input scalars have noise. In several initial experiments we have shown that our approach is numerically stable even for larger systems m = n = 100, provided the degrees in the solution are small (≤ 2). For smaller systems m = n = 10 with higher degrees (≤ 20) the algorithm works similarly to rational function recovery. Our implementation can correct 13 true errors in both settings.
The structure and dynamics of luminous and dark matter in the early-type lens galaxy of 0047-281 at z=0.485

We have measured the kinematic profile of the early-type (E/S0) lens galaxy in the system 0047-281 (z = 0.485) with the Echelle Spectrograph and Imager (ESI) on the W. M. Keck II Telescope, as part of the Lenses Structure and Dynamics (LSD) Survey. The central velocity dispersion is ? = 229 ? 15 km s-1, and the dispersion profile is nearly flat to beyond one effective radius (Re). No significant streaming motion is found. Surface photometry of the lens galaxy is measured from Hubble Space Telescope images. From the offset from the local fundamental plane (FP), we measure an evolution of the effective mass-to-light ratio (M/L) of ? log = -0.37 ? 0.06 between z = 0 and 0.485, consistent with the observed evolution of field E/S0 galaxies. (We assume h65 = 1, ?m = 0.3, and ?? = 0.7 throughout.) Gravitational lens models provide a mass of ME = ? 1011 h M? inside the Einstein radius of RE = h kpc. This allows us to break the degeneracy between velocity anisotropy and density profile typical of dynamical models for E/S0 galaxies. We find that constant-M/L models, even with strongly tangential anisotropy of the stellar velocity ellipsoid, are excluded at more than 99.9% CL. The total mass distribution inside RE can be described by a single power-law density profile, ?t r, with an effective slope ?' = 1.90 (68% CL; ?0.1 systematic error). Two-component models yield an upper limit (68% CL) of ? ? 1.55 on the power-law slope of the dark matter density profile and a projected dark matter mass fraction of 0.41(0.54)() (68% CL) inside RE, for Osipkov-Merritt models with anisotropy radius ri = ? . The stellar M*/L values derived from the FP agree well with the maximum allowed value from the isotropic dynamical models (i.e., the maximum-bulge solution). The fact that both lens systems 0047-281 (z = 0.485) and MG 2016+112 (z = 1.004) are well described inside their Einstein radii by a constant-M*/L stellar mass distribution embedded in a nearly logarithmic potential?with an isotropic or a mildly radially anisotropic dispersion tensor?could indicate that E/S0 galaxies underwent little structural evolution at z 1 and have a close-to-isothermal total mass distribution in their inner regions. Whether this conclusion can be generalized, however, requires the analysis of more systems. We briefly discuss our results in the context of E/S0 galaxy formation and cold dark matter simulations.
On the structure of conformally compact Einstein metrics

Let M be an (n + 1)-dimensional manifold with non-empty boundary, satisfying π1(M, ∂M) = 0. The main result of this paper is that the space of conformally compact Einstein metrics on M is a smooth, infinite dimensional Banach manifold, provided it is non-empty. We also prove full boundary regularity for such metrics in dimension 4 and a local existence and uniqueness theorem for such metrics with prescribed metric and stress–energy tensor at conformal infinity, again in dimension 4. This result also holds for Lorentzian–Einstein metrics with a positive cosmological constant.
Classically Normal Pure States

A pure state f of a von Neumann algebra \(\mathcal M\) is called classically normal if f is normal on any von Neumann subalgebra of \(\mathcal M\) on which f is multiplicative. Assuming the continuum hypothesis, a separably represented von Neumann algebra M has classically normal, singular pure states iff there is a central projection p ∈M such that pMp is a factor of type I∞, II, or III.
Stratified fibrations and the intersection homology of the regular neighborhoods of bottom strata

Abstract In this paper, we develop Leray–Serre-type spectral sequences to compute the intersection homology of the regular neighborhood and deleted regular neighborhood of the bottom stratum of a stratified PL-pseudomanifold. The E 2 terms of the spectral sequences are given by the homology of the bottom stratum with a local coefficient system whose stalks consist of the intersection homology modules of the link of this stratum (or the cone on this link). In the course of this program, we establish the properties of stratified fibrations over unfiltered base spaces and of their mapping cylinders. We also prove a folk theorem concerning the stratum-preserving homotopy invariance of intersection homology.
Ratio Asymptotics, Hessenberg Matrices, and Weak Asymptotic Measures

We discuss the relationship between ratio asymptotics for general orthogonal polynomials and the asymptotics of the associated Bergman shift operator. More specifically, we consider the case in which a measure is supported on an infinite compact subset of the complex plane. We show that there is a straightforward connection between the corresponding orthonormal polynomials exhibiting ratio asymptotics and the corresponding Bergman shift operator being asymptotically Toeplitz. We also discuss a connection to the weak asymptotics of the measures derived from the orthonormal polynomials.
Spectra of the night sky, the zodiacal light, the aurora, and the cosmic radiations of the sky

All who have thoughtfully looked upon the clear moonless night-sky are aware that it is not quite dark but that, besides the stars, planets, and Milky Way, it is everywhere faintly luminous. Believing valuable information would be gained regarding the nature and origin of this weak, diffuse sky-light by spectrographic investigation, I made, in 1915, at the Lowell Observatory, the first attempt to photograph its spectrum. Since then I have continued the study as opportunity has afforded, and with rather remarkable results.
Mergers of Close Primordial Binaries

We study the production of main-sequence mergers of tidally synchronized primordial short-period binaries. The principal ingredients of our calculation are the angular momentum loss rates inferred from the spin-down of open cluster stars and the distribution of binary properties in young open clusters. We compare our results with the expected number of systems that experience mass transfer in the post-main-sequence phases of evolution and compute the uncertainties in the theoretical predictions. We estimate that main-sequence mergers can account for the observed number of single blue stragglers in M67. Applied to the blue straggler population, this implies that such mergers are responsible for about one-quarter of the population of halo blue metal-poor stars and at least one-third of the blue stragglers in open clusters for systems older than 1 Gyr. The observed trends as a function of age are consistent with a saturated angular momentum loss rate for rapidly rotating tidally synchronized systems. The predicted number of blue stragglers from main-sequence mergers alone is comparable to the number observed in globular clusters, indicating that the net effect of dynamical interactions in dense stellar environments is to reduce rather than increase the blue straggler population. A population of subturnoff mergers of order 3%-4% of the upper main sequence population is also predicted for stars older than 4 Gyr, which is roughly comparable to the small population of highly Li-depleted halo dwarfs. Other observational tests are discussed.
Antinomicity and the axiom of choice. A chapter in antinomic mathematics

The present work is an attempt to break ground in mathematics proper, armed with the accepting view just described. Specifically, we shall examine various versions of antinomic set theory, in particular the axiom of choice, keeping the presentation as intuitive as possible, more in the manner of a nineteenth century paper than as a thoroughly formalized system. The reason for such a presentation is the conviction that at this point it should be the mathematics that eventually determines the logic, rather than the other way around.
Post-processing for decoding without update step in motion-compensated lifted wavelet video coding

Motion-compensated temporal filtering is an open-loop coding technique, which generally employs a motion-compensated update step. Although the update step is essential at the encoder for good rate-distortion efficiency, it might be skipped at the decoder for benefits like lower complexity and lower playout delay. Previous investigations showed that skipping the update step at the decoder results in some quality degradation at high rates. In this paper we analyze how this degradation arises and also propose a simple method to reduce this degradation. The proposed solution can also be implemented as a post-processing procedure after conventional decoding without the update step. Experimental results show that the degradation in quality is reduced by half. For our t+2D wavelet coder, this gives a gain of approximately 1.0 - 1.5 dB at high bit-rates.© (2007) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
No Correlation Between Host Galaxy Metallicity and Gamma-ray Energy Release for Long-duration Gamma-ray Bursts

We compare the redshifts, host galaxy metallicities, and isotropic (E{sub {gamma}},iso) and beaming-corrected (E{sub {gamma}}) gamma-ray energy release of 16 long-duration gamma-ray bursts (LGRBs) at z < 1. From this comparison, we find no statistically significant correlation between host metallicity and redshift, E{sub {gamma}},iso, or E{sub {gamma}}. These results are at odds with previous theoretical and observational predictions of an inverse correlation between gamma-ray energy release and host metallicity, as well as the standard predictions of metallicity-driven wind effects in stellar evolutionary models. We consider the implications that these results have for LGRB progenitor scenarios, and discuss our current understanding of the role that metallicity plays in the production of LGRBs.
The Hopf ring for complex cobordism

In [38] Thom defined the unoriented and oriented cobordism rings, soon generalized to complex cobordism by Milnor [19] and Novikov [22]. These geometric constructions were later shown to give rise to generalized homology and cohomology theories [39] by Atiyah [3]. These theories have received a great deal of attention in recent years. In this paper we offer three new things. First, we obtain unstable homotopy theoretic information from formal group laws. Second, we make essential use of the concept of Hopf rings both in the description of our results and in the proofs. Third, we give a detailed analysis of the homology structure of the (unstable) classifying spaces for complex cobordism, including a completely algebraic construction which contains total information about the unstable complex cobordism operations. Some of our results were announced in [29].
An alternative solid-phase approach to C1-oxytocin

Abstract A general, solid-phase method based on in situ formation of a cystathionine residue is described. The procedure allows for the introduction of a thioether moiety in place of a native disulfide bond and is illustrated here by the synthesis of C 1 -oxytocin 1 .
Compositionally controlled metal–insulator transition in Tl2−xInxTeO6

Abstract Tl2TeO6 and In2TeO6 are both known to crystallize in the Na2SiF6-type structure. We find Tl2TeO6 is metallic, whereas In2TeO6 is an insulator. We have prepared a complete Tl2−xInxTeO6 series in a search for a compositionally controlled metal–insulator transition that might be expected if a complete solid solution can be obtained. Unit cell edges and volume vary monotonically with no indication of a miscibility gap. The metal–insulator transition occurs at an x value of about 1.4, which can be rationalized on a percolation model. No superconductivity could be detected down to 5 K.
Studying the Past: The Nature and Development of Legal History as an Academic Discipline

This article pursues two themes. First, it argues that there is a commonality between the general interest in the past, the interest of historians, and the interest of legal historians. Second, it shows that several ideas about the past commonly appear in all three contexts. In pursuing these themes, the article begins by reviewing the initial study of the past and the emergence of history and legal history in academia. It explores the various reasons why the early historians and later academic historians and legal historians studied the past and the different ways in which they used it. The article then pursues in more detail the development of Anglo-American legal history as a scholarly tradition. It identifies three types of academic legal history: classical, liberal, and critical, and discusses their natures and different uses of the past. Finally, the article explores the substantial legal history scholarship and its relevance to scholars who are not legal historians. The article concludes by stressi...
Bowen fluorescence in the solar transition region.

In Bowen fluorescence, a 304-A photon of He II is converted into two optical photons and an EUV photon of O III. The fluorescent contribution to the intensity of the O III 374-A line is a measure of the column density of O III in the solar transition region. Division of the column density into the emission measure derived from other lines of O III allows determination of the electron density. The accuracy of this technique is roughly a factor of 2, which is comparable to the accuracy of the density diagnostics for the solar transition region.