cssi/SciSciGPT-SciSciNet huggingface dataset:
Characteristics of a successful space system engineer

The Far Ultraviolet Spectroscopic Explorer (FUSE) satellite was launched on June 24, 1999, on a three-year mission to explore the universe using the technique of high-resolution spectroscopy in the far-ultraviolet spectral region. The FUSE instrument comprises many subsystems, each of which contributes in an essential way to the success of the mission. The instrument system engineer oversees the engineering of all elements in such a complex technical project. In performing system engineering for the FUSE instrument's command, telemetry, data processing and data storage functions, and in leading the engineering efforts for the development of the FUSE instrument on-board computer, the author has learned valuable lessons about the characteristics that are prerequisite to success for a space system engineer. These characteristics fall under various categories of acquired, practical know-how. These categories are described with illustrations drawn from the development of the FUSE instrument. In addition to these practical skills and the concomitant knowledge, the system engineer needs personal integrity, which is the link that connects knowledge with know-how and makes them work together to motivate a team of subsystem engineers. This, too, will be discussed.
Improved queueing analysis of shared buffer switching networks

The authors describe several methods for analyzing the queueing behavior of switching networks with flow control and shared buffer switches. They compare the various methods on the basis of accuracy and computation speed, where the performance metric of most concern is the maximum throughput. The best of the methods accurately predicts throughput for multistage networks constructed from large switches (>or=8 ports). >
Numerical simulation of detonation processes in a variable cross-section chamber

*† The detonation processes occurring in a combustion chamber with variable cross-sections are numerically simulated for a hydrogen-air reacting flow. The chamber consists of a large diameter tube and two small identical tubes connected on each side through frustums. The channel is closed at the left end and opened at the right. A two-dimensional, time accurate, finite-volume-based method is used to perform the computations. A five-species, two-step global reaction mechanism is used. Two detonation cases are simulated, corresponding to initiation from the closed, left end and the opened, right end. The study showed that area change gave rise to complex wave phenomena. The area change and wave reflections yielded extreme parameters.
Intramolecular 1,3-dipolar cycloaddition as a tool for the preparation of azaspirocyclic keto aziridines. Synthesis of intermediates for the total synthesis of (±)-cephalotaxine

Abstract The thermal intramolecular azide-enone 1,3-dipolar cycloaddition to azaspirocyclic keto aziridines 17 and 18 is reported. α-Hydroxylation and oxidation to the corresponding diketo aziridine 2 provided an intermediate in a synthetic approach toward cephalotaxine 1.
Characterizing files in the modern gnutella network : A measurement study

The Internet has witnessed an explosive increase in the popularity of Peer-to-Peer (P2P) file-sharing applications during the past few years. As these applications become more popular, it becomes increasingly important to characterize their behavior in order to improve their performance and quantify their impact on the network. In this paper, we present a measurement study on characteristics of available files in the modern Gnutella system. We developed a new methodology to capture accurate "snapshots" of available files in a large scale P2P system. This methodology was implemented in a parallel crawler that captures the entire overlay topology of the system where each peer in the overlay is annotated with its available files. We have captured tens of snapshots of the Gnutella system and conducted three types of analysis on available files: (i) Static analysis, (ii) Topological analysis and (iii) Dynamic analysis. Our results reveal several interesting properties of available files in Gnutella that can be leveraged to improve the design and evaluations of P2P file-sharing applications.
Polytopic control Lyapunov functions for robust stabilization of a class of nonlinear systems

Abstract We develop a method for computing a region in state space over which a nonlinear system is guaranteed by a given polytopic control Lyapunov function to be stable in closed loop under some appropriate control law. For systems which are nonlinear in only a few state variables, the procedure is computationally tractable; the computation time required to evaluate stability over each cone comprising a level set of the Lyapunov function is exponential in the number of “nonlinear states” but otherwise polynomial in the dimension of the full state space. Control constraints and robustness to bounded disturbances are easily incorporated.
New topologically slice knots

In the early 1980’s Mike Freedman showed that all knots with trivial Alexander polynomial are topologically slice (with fundamental group Z). This paper contains the first new examples of topologically slice knots. In fact, we give a sufficienthomological condition under which a knot is slice with fundamental group Z ⋉ Z[1/2]. These two fundamental groups are known to be the only solvable ribbon groups. Our homological condition implies that the Alexander polynomial equals (t − 2)(t 1 − 2) but also contains information about the metabelian cover of the knot complement (since there are many non-slice knots with this Alexander polynomial).
An Extremal Inequality Motivated by Multiterminal Information-Theoretic Problems

We prove a new extremal inequality, motivated by the vector Gaussian broadcast channel and the distributed source coding with a single quadratic distortion constraint problems. As a corollary, this inequality yields a generalization of the classical entropy-power inequality (EPI). As another corollary, this inequality sheds insight into maximizing the differential entropy of the sum of two dependent random variables
An Information Structural Approach To Spoken Language Generation

This paper presents an architecture for the generation of spoken monologues with contextually appropriate intonation. A two-tiered information structure representation is used in the high-level content planning and sentence planning stages of generation to produce efficient, coherent speech that makes certain discourse relationships, such as explicit contrasts, appropriately salient. The system is able to produce appropriate intonational patterns that cannot be generated by other systems which rely solely on word class and given/new distinctions.
Impacts of an anomalously warm year on soil nitrogen availability in experimentally manipulated intact tallgrass prairie ecosystems.

Global climate change can potentially increase the frequency of climate anomalies. Anomalously warm years may cause an increase in soil nitrogen (N) availability by stimulating N mineralization. To date, most studies addressing the effects of ecosystem warming have been conducted in relatively cold ecosystems and few studies have addressed impacts of interannual as opposed to continuous, multiyear warming. In this study, 12 intact soil monoliths were excavated from a tallgrass prairie site near Purcell, Oklahoma, USA and divided among four large flux chambers (EcoCELLs). During the first year, all four EcoCELLs were subjected to Oklahoma air temperatures and precipitation. During the second year, air temperature in two EcoCELLs was increased by 4 °C throughout the year resulting in an increase in soil temperature of 2.3 °C at 7.5 cm depth. During the third and fourth years, temperatures in the warmed EcoCELL returned back to ‘normal’ conditions. During the warming year, vegetation N content was not significantly affected by the warming treatment suggesting no change in N availability. Other N availability indicators (soil solution chemistry, leaching, and N adsorption by ion exchange resins) did not show any effect of warming. Soil solution, leaching, and ion exchange resins showed a large pulse of NH4+ at the start of the study most likely due to disturbance caused by monolith excavation and transport but these effects were short-lived and had disappeared before the treatment started. The lack of a clear warming effect may be explained by a reduction in soil moisture in the warming treatments compared with the controls offsetting a potential stimulation of N mineralization in response to increased temperatures. As a result, effects of an anomalously warm year on N availability in warmer ecosystems may be small compared with colder ecosystems but are likely to depend on soil moisture status.
A Multilevel Solver for Boundary Value Problems

Multilevel methods have been studied extensively for solving certain partial differential equations, and such equation solvers have been successfully applied to major computational problems of physical interest and technological importance. KLEV is a collection of routines for solving the N X N system of linear equations Az = g when A and g are discretizations of some partial differential equation. The current release includes a direct method, iterative methods, and multilevel methods. A brief review of multilevel methods and an overview of the implementation are presented.
Biosynthesis of proteins incorporating a versatile set of phenylalanine analogues.

Unnatural amino acids with useful chemical functionality can replace phenylalanine in bacterial proteins. Coexpression of a promiscuous phenylalanine-tRNA synthetase mutant enables the synthesis of target proteins bearing iodophenyl, cyanophenyl, ethynylphenyl, azidophenyl, and pyridyl groups (see general structures). Proteins incorporating the analogues have a range of potential applications, including Pd-mediated conjugation (R=CCH), photoaffinity labeling (R=N_3), X-ray phasing (R=I), and novel metal coordination (R=pyridyl).
Stockholder Unanimity in Making Production and Financial Decisions

We show that "spanning" does not imply stockholder unanimity if there is trading in the shares of firms. Each basis vector of the space spanned by all firms' output vectors can be treated like a composite commodity. If, in addition to spanning, firms act as price takers with respect to prices of composite commodities, then there is unanimity. We analyze the spanning assumption for the vector space of contingent claims generated by firms' choices of debt-equity ratios. We show that there is a strong relationship between the Modigliani-Miller theorem, spanning, and the existence of a complete set of markets.
Surface waves in orthotropic incompressible materials

The secular equation for surface acoustic waves propagating on an orthotropic incompressible half-space is derived in a direct manner, using the method of first integrals.
Cutting Triangular Cycles of Lines in Space

We show that n lines in 3-space can be cut into O(n2-1/69log16/69n) pieces, such that all depth cycles defined by triples of lines are eliminated. This partially resolves a long-standing open problem in computational geometry, motivated by hidden-surface removal in computer graphics.
In Chemotaxing Fibroblasts, Both High-Fidelity and Weakly Biased Cell Movements Track the Localization of PI3K Signaling

Cell movement biased by a chemical gradient, or chemotaxis, coordinates the recruitment of cells and collective migration of cell populations. During wound healing, chemotaxis of fibroblasts is stimulated by platelet-derived growth factor (PDGF) and certain other chemoattractants. Whereas the immediate PDGF gradient sensing response has been characterized previously at the level of phosphoinositide 3-kinase (PI3K) signaling, the sensitivity of the response at the level of cell migration bias has not yet been studied quantitatively. In this work, we used live-cell total internal reflection fluorescence microscopy to monitor PI3K signaling dynamics and cell movements for extended periods. We show that persistent and properly aligned (i.e., high-fidelity) fibroblast migration does indeed correlate with polarized PI3K signaling; accordingly, this behavior is seen only under conditions of high gradient steepness (>10% across a typical cell length of 50 μm) and a certain range of PDGF concentrations. Under suboptimal conditions, cells execute a random or biased random walk, but nonetheless move in a predictable fashion according to the changing pattern of PI3K signaling. Inhibition of PI3K during chemotaxis is accompanied by loss of both cell-substratum contact and morphological polarity, but after a recovery period, PI3K-inhibited fibroblasts often regain the ability to orient toward the PDGF gradient.
Trees in a treemap: visualizing multiple hierarchies

This paper deals with the visual representation of a particular kind of structured data: trees where each node is associated with an object (leaf node) of a taxonomy. We introduce a new visualization technique that we call Trees In A Treemap. In this visualization edges can either be drawn as straight or orthogonal edges. We compare our technique with several known techniques. To demonstrate the usability of our visualization techniques, we apply them to find interesting patterns in decision trees and network routing data.
The impact of soil conservation and output diversification on farm income in Central American hillside farming

This article analyzes the determinants of farm income among hillside farmers participating in natural resource management projects in El Salvador and Honduras. The farm income function was evaluated using a system of equations in which income is determined simultaneously by the farmer's decision to adopt soil conservation technologies and by the level of diversification (number of agricultural activities) on the farm. The database used comes from surveys administered to 678 beneficiaries of these projects during 2002. The econometric results suggest that all the variables related directly to land use (i.e., output diversification, soil conservation practices and structures, and the adoption of forestry systems) have a positive and statistically significant association with farm income. Also, farmers who own land enjoy higher farm incomes than those who do not. The results indicate that when investing in natural resource management projects, governments and multilateral development agencies should pay close attention to output diversification, land tenure, and human capital formation as effective instruments in increasing farm income.
Intellectual Property Rights, Foreign Direct Investment, and Industrial Development

This paper develops a North-South product cycle model in which innovation, imitation, and the ‡ow of FDI are all endogenously determined. In the model, a strengthening of IPR protection in the South reduces the rate of imitation and it increases the ‡ow of FDI. Indeed,
Conformal blocks in the large D limit

We derive conformal blocks in an inverse spacetime dimension expansion. In this large D limit, the blocks are naturally written in terms of a new combination of conformal cross-ratios. We comment on the implications for the conformal bootstrap at large D.
Consumer Bankruptcy and Financial Health

This paper estimates the effect of Chapter 13 bankruptcy protection on financial health using a new data set linking bankruptcy filings to credit bureau records. Our empirical strategy uses the leniency of randomly assigned judges as an instrument for Chapter 13 protection. We find that Chapter 13 protection decreases an index measuring adverse financial events such as civil judgments and repossessions by 0.323 standard deviations and increases the probability of being a homeowner by 13.2 percentage points. Chapter 13 protection has little impact on open unsecured debt but decreases the amount of debt in collections by $1,333.
Cognitive skill and technology diffusion: An empirical test

Abstract Cognitive skills are robustly associated with good national economic performance. How much of this is due to high-skill countries doing a better job of absorbing total factor productivity from the world's technology leader? Following Benhabib and Spiegel (Handbook of Economic Growth, 2005) , who estimated the Nelson–Phelps technology diffusion model, I use the database of IQ tests assembled by Lynn and Vanhanen, 2002 , Lynn and Vanhanen, 2006 and find a robust relationship between national average IQ and total factor productivity growth. Controlling for IQ, years of education is of modest statistical significance. If IQ gaps between countries persist and model parameters remain stable, TFP levels are forecasted to sharply diverge, creating a “twin peaks” result. After controlling for IQ, few other growth variables are statistically significant.
Holding India Together: The Role of Institutions of Federalism

India is a large, heterogeneous and complex nation, with multiple languages, religions and ethnicities, and over one billion people. It stands out in having held together while sustaining a working democracy for over five decades, at relatively low levels of income. One of the main institutional aspects of managing heterogeneity to preserve national unity is the structures of Indian federalism. This paper traces some of the features of Indian federal institutions, focusing on their contribution to this ‘holding together.’ It reviews the conceptual and analytical underpinnings of the role of federal structures in sustaining unity, and summarizes historical developments and current institutional structures of the Indian case. It assesses the role of federal dimensions of political, administrative and judicial structures in the holding together function. It also examines fiscal federal institutions and their impacts, including distributional and growth issues. It also separately focuses specifically on the special treatment of what may be characterized as India’s periphery.
Enhancing Otto‐Mobile Efficiency via Addition of a Quantum Carnot Cycle

It was shown recently that one can improve the efficiency of the Otto cycle by taking advantage of the internal degrees of freedom of an ideal gas [M. O. Scully, ‘‘The Quantum Afterburner”, Phys. Rev. Lett., to be published]. Here we discuss the limiting improvement of the efficiency by considering reversible cycles with both internal and external degrees of freedom.
Examining the link between teacher wages and student outcomes: The importance of alternative labor market opportunities and non-pecuniary variation

Researchers using cross-sectional data have failed to produce systematic evidence that teacher salaries affect student outcomes. These studies generally do not account for non-pecuniary job attribu...
English Economic Growth in the Eighteenth Century: A Re‐Examination of Deane and Cole's Estimates

C HAPTER II of British Economic Growth2 represents a radical departure from earlier views of the eighteenth century. It suggests that there were two major turning points in the growth of the economy, in the I 740's and the I 780's, and that the classic innovations of the years after I 760 should be regarded as results rather than prime movers of growth. It is also argued that unfavourable intersectoral terms of trade for agriculture and absence of population growth inhibited economic growth up to the I 740's whereas rapid population growth, and associated with it high relative prices for agriculture, stimulated economic growth thereafter by creating buoyant domestic market conditions for the industrial sector. The purpose of this article is to re-examine the construction of Deane and Cole's real output index, which constitutes the principal quantitative support for their hypotheses. In particular the plausibility of the assumptions used in the treatment of the agricultural sector is questioned in section i. Alternative and, it will be maintained, more satisfactory assumptions are used to provide revised estimates in section ii, the robustness and implications of which are discussed in section iii.
Solar Activity and Cloud Opacity Variations: A Modulated Cosmic Ray Ionization Model

Abstract The observed correlation between global low cloud amount and the flux of high energy cosmic rays supports the idea that ionization plays a crucial role in tropospheric cloud formation. This idea is explored quantitatively with a simple model linking the concentration of cloud condensation nuclei to the varying ionization rate due to cosmic rays. Among the predictions of the model is a variation in global cloud optical thickness, or opacity, with cosmic ray rate. Using the International Satellite Cloud Climatology Project (ISCCP) database (1983–99), a search was conducted for variations in the yearly mean visible cloud opacity and visible cloud amount due to cosmic rays. After separating out temporal variations in the data due to the Mount Pinatubo eruption and El Nino–Southern Oscillation, systematic variations in opacity and cloud amount due to cosmic rays were identified. It was found that the fractional amplitude of the opacity variations due to cosmic rays increases with cloud altitude, becom...
Quantitative Robust Uncertainty Principles and Optimally Sparse Decompositions

In this paper we develop a robust uncertainty principle for finite signals in ${\Bbb C}^N$ which states that, for nearly all choices $T, \Omega\subset\{0,\ldots,N-1\}$ such that $|T| + |\Omega| \asymp (\log N)^{-1/2} \cdot N,$ there is no signal $f$ supported on $T$ whose discrete Fourier transform $\hat{f}$ is supported on $\Omega.$ In fact, we can make the above uncertainty principle quantitative in the sense that if $f$ is supported on $T,$ then only a small percentage of the energy (less than half, say) of $\hat{f}$ is concentrated on $\Omega.$ As an application of this robust uncertainty principle (QRUP), we consider the problem of decomposing a signal into a sparse superposition of spikes and complex sinusoids $f(s) = \sum_{t\in T}\alpha_1(t)\delta(s-t) + \sum_{\omega\in\Omega}\alpha_2(\omega)e^{i2\pi \omega s/N}/\sqrt{N}.$ We show that if a generic signal $f$ has a decomposition $(\alpha_1,\alpha_2)$ using spike and frequency locations in $T$ and $\Omega,$ respectively, and obeying $|T| + |\Omega| \leq {\rm Const}\cdot (\log N)^{-1/2}\cdot N,$ then $(\alpha_1, \alpha_2)$ is the unique sparsest possible decomposition (all other decompositions have more nonzero terms). In addition, if $|T| + |\Omega| \leq {\rm Const}\cdot (\log N)^{-1}\cdot N,$ then the sparsest $(\alpha_1,\alpha_2)$ can be found by solving a convex optimization problem. Underlying our results is a new probabilistic approach which insists on finding the correct uncertainty relation, or the optimally sparse solution for nearly all subsets but not necessarily all of them, and allows us to considerably sharpen previously known results [9], [10]. In fact, we show that the fraction of sets $(T, \Omega)$ for which the above properties do not hold can be upper bounded by quantities like $N^{-\alpha}$ for large values of $\alpha.$ The QRUP (and the application to finding sparse representations) can be extended to general pairs of orthogonal bases $\Phi_1,\Phi_2 \mbox{of} {\Bbb C}^N.$ For nearly all choices ${\Gamma_1},{\Gamma_2}\subset\{0,\ldots,N-1\}$ obeying $|{\Gamma_1}| + |{\Gamma_2}| \asymp \mu(\Phi_1,\Phi_2)^{-2} \cdot (\log N)^{-m},$ where $m\leq 6,$ there is no signal $f$ such that $\Phi_1 f$ is supported on ${\Gamma_1}$ and $\Phi_2 f$ is supported on ${\Gamma_2}$ where $\mu(\Phi_1,\Phi_2)$ is the mutual coherence between $\Phi_1$ and $\Phi_2.$
QSO 2359?1241: A Bright, Highly Polarized, Radio-moderate, Reddened, Low-Ionization Broad Absorption Line Quasar

We report the discovery of a bright quasar (E = 15.8, z = 0.868) associated with the flat-spectrum radio source NVSS J235953-124148. This quasar, which we designate QSO 2359-1241, possesses a rare combination of extreme properties that make it of special interest. These properties include intrinsic high-velocity outflow seen in absorption for both high- and low-ionization species, high optical polarization (~5%), significant radio emission, and dust reddening. The dereddened absolute magnitude of QSO 2359-1241 places it among the three most optically luminous quasars known at z < 1. High-resolution spectroscopy and a detailed analysis of the optical/ultraviolet absorption features will be given in a companion paper.
Optical 'shorting wires'.

Connecting lumped circuit elements in a conventional circuit is usually accomplished by conducting wires that act as conduits for the conduction currents with negligible potential drops. More challenging, however, is to extend these concepts to optical nanocircuit elements. Here, following our recent development of optical lumped circuit elements, we show how a special class of nanowaveguides formed by a thin core with relatively large (positive or negative) permittivity surrounded by a thin concentric shell with low permittivity may provide the required analogy to ‘wires’ for optical nano-circuits.
Sign variation, the Grassmannian, and total positivity

The totally nonnegative Grassmannian is the set of k-dimensional subspaces V of R n whose nonzero Plucker coordinates all have the same sign. Gantmakher and Krein (1950) and Schoenberg and Whitney (1951) independently showed that V is totally nonnegative iff every vector in V, when viewed as a sequence of n numbers and ignoring any zeros, changes sign at most k - 1 times. We generalize this result from the totally nonnegative Grassmannian to the entire Grassmannian, showing that if V is generic (i.e. has no zero Plucker coordinates), then the vectors in V change sign at most m times iff certain sequences of Plucker coordinates of V change sign at most m - k + 1 times. We also give an algorithm which, given a non-generic V whose vectors change sign at most m times, perturbs V into a generic subspace whose vectors also change sign at most m times. We deduce that among all V whose vectors change sign at most m times, the generic subspaces are dense. These results generalize to oriented matroids. As an application of our results, we characterize when a generalized amplituhedron construction, in the sense of Arkani-Hamed and Trnka (2013), is well defined. We also give two ways of obtaining the positroid cell of each V in the totally nonnegative Grassmannian from the sign patterns of vectors in V.
Electronic transitions in [Re6S8X6](4-) (X = Cl, Br, I): results from time-dependent density functional theory and solid-state calculations.

Relativistic time-dependent density functional theory (TDDFT) calculations were performed on the excited states of the [Re 6 S 8 X 6 ] 4- (X = Cl, Br, I) series. For all members of the series, the lowest excited states in the spectra do not correspond to a ligand-to-metal (or ligand-to-cluster) excitation but rather a cluster-cluster transition from the HOMO eg to antibonding t 1u orbitals with only a modest admixture of Re-X σ* character. These results lead to a re-evaluation of the role of the axial ligand in these compounds. The calculated excitation energies reproduce the experimental absorption and emission spectra. This work also confirms previous TDDFT calculations on the emission energies. Results for discrete cluster ions are compared with those obtained from calculations in the solid state in Cs 4 [Re 6 S 8 X 6 ]·CsX (X = Cl, Br) and Cs 4 [Re 6 S 8 I 6 ]·2CsI. Significant differences are seen in the relatively higher energies of the antibonding t 1u orbital in the solid-state case, and an inversion in the orbital character of the two allowed absorptions is calculated. The eg (HOMO)-to-a 2g (LUMO) orbital energy differences corresponding to the emission transition are quite comparable for the solid state and discrete cluster calculations, and both overestimate the observed emission energy by the same margin.
Jitter Induced Clutter In Staring Sensors Arising From Background Spatial Radiance Gradients

Jitter induced clutter in a staring sensor depends on the spatial gradients of background radiance, the detector footprint, and the line-of-sight jitter frequency characteristics. The clutter problem is most severe when there are sharp radiance gradients or edges in the scene; clutter models which describe the background by a spatial power spectrum lose the edge information. The model developed in this paper relates clutter directly to background radiance gradients and the sensor characteristics. The rms clutter is expressed in terms of structure function statistics of the background. The distribution of clutter amplitudes is not Gaussian (even for Gaussian jitter and spatially Gaussian backgrounds); extreme values occur much more often than predicted Gaussian analyses. These extreme values affect sensor threshold levels and the associated system data rates. An effective "jitter equivalent angle" is derived for the sensor which is independent of the background. Analysis of Skylab photos in the visible and near IR spectral regions indicates radiance gradients are approximately exponentially distributed and the rms jitter clutter is proportional to the footprint size raised to the 1.5 power.
Low-cost, dual-mode enhanced vision sensor prototype

As a member of the Southeast SATSLab Consortium and participant in the NASA Small Aircraft Transportation System (SATS) program, the Rockwell Collins Advanced Technology Center has developed a flyable prototype of a low-cost, dual-mode enhanced vision sensor (EVS). The prototype has been successfully flown on Embry-Riddle Aeronautical University's experimental Cessna 310 light twin aircraft. The dual-mode system incorporates an uncooled long wave infrared sensor and a low-light level visible light imager using a common aperture. The system includes a dichroic beamsplitter that provides the same coaxial field of view to both sensors. This paper describes the design, fabrication, sensor performance, and flight test results of the enhanced vision sensor prototype
Density Stratified, Viscous Flow past a Flat Plate

Analytical approximations of the stratified, laminar flow past a flat plate are considered. Perturbation solutions are obtained for the flow on the plate and in the far wake with a boundary-layer type of approximation and for the whole flowfield with a low Reynolds' number approximation. The boundary-layer approximate solutions show that the wall shear on the plate is increased and that the rate of decay of the velocity defect in the wake is markedly increased. In the low Reynolds' number regime, the effects of the stratification are much larger ahead of and behind the plate than on the plate itself.
Anthropology and Militarism

Anthropologists’ selections of topics and field sites have often been shaped by militarism, but they have been slow to make militarism, especially American militarism, an object of study. In the high Cold War years concerns about human survival were refracted into debates about innate human proclivities for violence or peace. As “new wars” with high civilian casualty rates emerged in Africa, Central America, the former Eastern bloc, and South Asia, beginning in the 1980s anthropologists increasingly wrote about terror, torture, death squads, ethnic cleansing, guerilla movements, and the memory work inherent in making war and peace. Anthropologists have also begun to write about nuclear weapons and American militarism. The “war on terror” has disturbed settled norms that anthropologists should not assist counterinsurgency campaigns, and for the first time since Vietnam, anthropologists are debating the merits of military anthropology versus critical ethnography of the military.
Ultrahigh resolution photoacoustic microscopy via transient absorption

We have developed a novel, hybrid imaging modality, Transient Absorption Ultrasonic Microscopy (TAUM), which fuses photoacoustic microscopy with non-linear microscopy. Photoacoustic microscopy is well known for its ability to image chromophores deep (> 1 mm) in scattering media with spatial resolutions in the 10s of microns. Non-linear microscopy is well known for its exquisite spatial resolution in three dimensions. This superior spatial resolution is attributed to the fact that the collected signal has a non-linear dependence on the light intensity. This dependence confines the signal to a very small focal volume, producing optically resolved voxels. Transient absorption is a non-linear process often used to map the excited state lifetimes of molecules exhibiting low fluorescence quantum efficiency. This sensitivity to non-radiative transitions makes transient absorption an attractive process to combine with photoacoustic imaging. We have built a prototype transient absorption ultrasonic microscope, implementing off-axis photoacoustic detection to allow the use of a high-quality, high numerical aperture objective. This high-quality, commercial lens is required to provide the tight focusing needed to optimize non-linear effects. We have demonstrated the increased spatial resolution of TAUM by imaging Rhodamine 6G in a capillary tube. The capillary cross-section is fully resolved, suggesting an axial resolution of < 10 microns. A 6 MHz transducer was used in this experiment, which results in an axial resolution of ~ 400 microns when used in a traditional photoacoustic microscope. Boasting the superior penetration depth and absorption contrast offered by photoacoustic emission and complemented by spatial resolutions comparable to confocal microscopy, we believe that Transient Absorption Ultrasonic Microscopy has excellent potential for producing volumetric images with cellular/subcellular resolution in three dimensions deep inside living tissue.
Existence of optimal maps in the reflector-type problems

In this paper, we consider probability measures μ and ν on a d -dimensional sphere in and cost functions of the form that generalize those arising in geometric optics where We prove that if μ and ν vanish on -rectifiable sets, if |l'(t)|>0, and is monotone then there exists a unique optimal map T o that transports μ onto where optimality is measured against c. Furthermore, Our approach is based on direct variational arguments. In the special case when existence of optimal maps on the sphere was obtained earlier in [Glimm and Oliker, J. Math. Sci. 117 (2003) 4096-4108] and [Wang, Calculus of Variations and PDE's 20 (2004) 329-341] under more restrictive assumptions. In these studies, it was assumed that either μ and ν are absolutely continuous with respect to the d -dimensional Haussdorff measure, or they have disjoint supports. Another aspect of interest in this work is that it is in contrast with the work in [Gangbo and McCann, Quart. Appl. Math. 58 (2000) 705-737] where it is proved that when l(t)=t then existence of an optimal map fails when μ and ν are supported by Jordan surfaces.
Communication, Risk, and Efficiency in Games☆☆☆

Abstract This paper uses curb sets to study the evolution of effective pre-play communication in games where a single communication round precedes a simultaneous-move, complete-information game. It is shown that the effectiveness of one-sided pre-play communication is inversely related to risk in the underlying game, and to the size of the message space. If messages have somea prioriinformation content, then multi-sided communication is more effective than one-sided communication; i.e., risk and the size of the message space play no role.Journal of Economic LiteratureClassification Number: C72.
Documentation of the AMIP Models on the World Wide Web

Abstract Summary documentation of the numerics, dynamics, and physics of models participating in the Atmospheric Model Intercomparison Project is now available on the Internet's World Wide Web. In this article the principal attributes of the electronic model documentation are described and instructions on how to access it are provided.
Tax-Induced Trading of Equity Securities: Evidence from the ADR Market

We examine ex-dividend date trading of American Depositary Receipts (ADRs) using a sample of 1,043 dividends over the period 1988 to 1995. ADR dividends are often subject to foreign withholding taxes, creating incentives for certain investors to avoid the distribution. ADRs exhibit negative abnormal ex-dividend day returns, and their prices behave consistently with their related withholding taxes. Abnormal trading volume for taxable issues exceeds 130 percent and 300 percent of normal volume on the cum- and ex-dates, respectively. Abnormal volume is an increasing function of foreign withholding tax rates and decreasing function of transactions costs. This abnormal exdate trading activity is consistent with tax-motivated trading. THIS PAPER PROVIDES EMPIRICAL EVIDENCE from a sample of American Depositary Receipts (ADRs) that foreign taxes on dividend income are positively associated with abnormal ex-dividend day trading activity. Researchers have long been interested in the question of whether taxes affect investor behavior around ex-dividend days. Such work has implications for corporate financial and distribution policies and for government tax policies. ADRs provide a unique setting in which to examine the effects of taxes on investor trading behavior because of the unique features of the foreign withholding taxes that apply to them. A number of studies have attempted to isolate the determinants of ex-dividend day pricing and trading activity of U.S. equities, and there is considerable evidence of tax-induced investor behavior around the ex-dividend day for common
Comparatively Evaluating Potential Dissertation and Thesis Projects

Graduate students suffer from many pressures when writing a dissertation. Deadlines loom, jobs are highly competitive, publishing is always a bonus, and these are often combined with outside research, teaching fellowships, or other occupations. In order to finish a quality dissertation without too much wasted time or effort it is useful for students to begin early and to think hard about their projects in a variety of ways. Students may have a broad conceptual interest or field interest without a focused and tractable project. In addition to the normal practice of discussing potential projects with advisors and mentors, there are several ways to evaluate potential projects that may be overlooked. This essay helps bring a good dissertation project to the front of several potential ideas a student might have by describing several characteristics for comparison across topics. In addition, this essay provides a rubric by which students can develop and discuss a project with faculty and colleagues. Without a doubt, one of the most important aspects of preparing a dissertation project is to discuss that project with faculty mentors and potential committee members (Banesh 2001). Between these discussions, or before the first discussion of potential projects, students can spend considerable time thinking about various ideas for their thesis or dissertation. Students approaching their project systematically may have many projects they are considering and wish to narrow down those projects to a manageable few before discussing them with advisors. As a first time dissertation writer, however, most graduate students are unaware of criteria that can be used to evaluate and compare their ideas objectively so they can compare several project ideas and narrow down the field. The criteria described here combine and extend other criteria previously developed, such as developing questions that are important in the real world and those that contribute to scholarly literature (King, Keohane, and Verba 1994). The criteria described below were developed specifically for dissertation projects, but are also very useful for students writing theses for other purposes such as undergraduate senior projects. The guide provided here should enable students to compare several potential ideas objectively to begin to find a viable project. Although the initial development of a thesis project based on a student's theoretical or empirical interests is mostly idiosyncratic and personal (See King, Keohane, and Verba 1994; Van Evera 1997), once a student's interests emerge there are some common ways to objectively evaluate several dissertation projects. This essay helps students develop several ways to think about their dissertation projects and create a rubric so that several projects can be evaluated on comparable terms.Thanks to the two anonymous reviewers and Ronald B Mitchell who made instrumental suggestions on improving the text.
Resonant clocking using distributed parasitic capacitance

A resonant-clock generation and distribution scheme that uses the inherent, parasitic capacitance of the clocked logic as a lumped capacitor in a negative-resistance oscillator is described. Clock energy is resonated between inductors and the parasitic, local clock network to save power over traditional clocking methodologies. Theory predicts that the data passing though the clocked logic will change the clock frequency by less than 1.25%. A resonant clock test chip was designed and fabricated in an IBM 0.13-/spl mu/m partially depleted SOI process. Although the test chip was designed to operate in the gigahertz range using integrated inductors, startup difficulties required the addition of external inductance to reduce the resonant frequency so that the effects of the parasitic capacitance could be measured. The parasitic capacitance is approximately 40 pF per clock phase, resulting in a clock frequency between 106 and 146 MHz, depending on biasing. At its most efficient bias point, the clock dissipated 2.09 mW, which is approximately 35% less power than a conventional, buffer-driven clock. The maximum period jitter measured in the resonant clock due to changing data in the clocked latches was 55 ps at 124 MHz, or 0.68% of the clock period.
A highly convergent total synthetic route to glycopeptides carrying a high-mannose core pentasaccharide domain N-linked to a natural peptide motif

N-Linked glycopeptides were synthesized by condensation of a highmannose anomeric amine bearing a pentasaccharide with aspartic-acid-containing tri- and pentapeptides through the agency of IIDQ. The pentasaccharide portion, corresponding to the „core” region of all asparagine-linked glycoproteins, was assembled by means of glycal-derived thioethyl donors and glycal acceptors. The central mannose residue was established by inversion of the C2 hydroxyl of a glucosyl precursor in the pentasaccharide. The protecting-group scheme employed allows the extension of the pentasaccharide through the terminal mannose units. While a fully convergent coupling of the high-mannose carbohydrate to the peptide domain has thus been accomplished for the first time with a fully synthetic sugar, the stereochemical integrity of the anomeric center of the carbohydrate domain was not maintained and a mixture of glycopeptides was obtained.
Filling the Bose sea: symmetric quantum Hall edge states and affine characters

We explore the structure of the bosonic analogues of the k-clustered 'parafermion' quantum Hall states. We show how the many-boson wavefunctions of k-clustered quantum Hall droplets appear naturally as matrix elements of ladder operators in integrable representations of the affine Lie algebra . Using results of Feigin and Stoyanovsky, we count the dimensions of spaces of symmetric polynomials with given k-clustering properties and show that as the droplet size grows the partition function of its edge excitations evolves into the character of the representation. This confirms that the Hilbert space of edge states coincides with the representation space of the edge-current algebra. We also show that a spin-singlet, two-component k-clustered boson fluid is similarly related to integrable representations of . Parafermions are not necessary for these constructions.
Vortex Dynamics and Shedding of a Low Aspect Ratio, Flat Wing at Low Reynolds Numbers and High Angles of Attack

This study focuses on the detection and characterization of vortices in low Reynolds number separated flow over the elliptical leading edge of a low aspect ratio, flat plate wing. Velocity fields were obtained using the time-resolved particle image velocimetry. Experiments were performed on a wing with aspect ratio of 0.5 for velocities of 1.1 m/s, 2.0 m/s, and 5.0 m/s corresponding to chord length Reynolds numbers of 1.4710 4 , 2.6710 4 , and 6.6710 4 , respectively, and angles of attack of 14 deg, 16 deg, 18 deg, and 20 deg. A local swirl calculation was used on proper orthogonal decomposition filtered data for vortex identification and corresponding vortex centers were tracked to determine convective velocities. The swirl function was also analyzed for its temporal frequency response at several discrete points in both the shear layer and in the separated recirculation region. A peak frequency was detected in the shear layer with a corresponding Strouhal number of approximately 3.4 based on the flow direction projected length scale. The Strouhal number increases with both angle of attack and Reynolds number. The shear layer convective length scale, based on the vortex convection velocity, is found to be consistent with the mean separation distance between vortices within the shear layer. This length scale decreases with increasing Rec. DOI: 10.1115/1.3112385
Political Uncertainty, Financial Crisis and Market Volatility

This paper examines the impact of political uncertainty on financial crises using a panel of twenty-two emerging markets. By examining political election cycles, we find that eight out of nine of the financial crises happened during the periods of political election and transition. Using a combination of probit and switching regression analysis, we find that there is a significant relationship between political election and financial crisis after controlling for differences in economic and financial conditions. We observe increased market volatility during political election and transition periods. Our results suggest that political uncertainty could be a major contributing factor to financial crisis. Thus, politics does matter in emerging markets. Since the odds of financial crisis tend to be much larger during the political election periods, institutonal investors should take that into account when making emerging market investment during those time periods.
Homocatenation of aluminum: alkane-like structures of Li2Al2H6 and Li3Al3H8.

A new class of aluminum homocatenated compounds (LinAlnH2n+2) is proposed based on quantum chemical calculations. In these compounds, Al abstracts an electron from Li, becoming valence isoelectronic with C, Si, and Ge, thus mimicking respective structural features of Group 14 hydrides. Using the Coalescence Kick search program coupled with density functional theory calculations, we investigated the potential energy surfaces of Li2Al2 H6 and Li3Al3H6 . Then single-point-energy coupled-cluster calculations were performed for the lowest energy structures found. Indeed, the global minima established for Li2 Al2 H6 and Li3 Al3 H6 contain the Al2 H6(2-) and Al3H6(3-) kernels, which are isostructural with ethane (C2H6), disilane (Si2H6), digermane (Ge2 H6) and propane (C3H8), trisilane (Si3H8), trigermane (Ge3H8) molecules, respectively. Structural, energetic, and electronic characteristics of the Li2 Al2 H6 and Li3 Al3 H8 compounds are presented and the viability of their synthesis is discussed.