cssi/SciSciGPT-SciSciNet huggingface dataset:
Independence Complexes of Stable Kneser Graphs

For integers $n\geq 1$, $k\geq 0$, the stable Kneser graph $SG_{n,k}$ (also called the Schrijver graph ) has as vertex set the stable $n$-subsets of $[2n+k]$ and as edges disjoint pairs of $n$-subsets, where a stable $n$-subset is one that does not contain any $2$-subset of the form $\{i,i+1\}$ or $\{1,2n+k\}$. The stable Kneser graphs have been an interesting object of study since the late 1970's when A. Schrijver determined that they are a vertex critical class of graphs with chromatic number $k+2$. This article contains a study of the independence complexes of $SG_{n,k}$ for small values of $n$ and $k$. Our contributions are two-fold: first, we prove that the homotopy type of the independence complex of $SG_{2,k}$ is a wedge of spheres of dimension two. Second, we determine the homotopy types of the independence complexes of certain graphs related to $SG_{n,2}$.
Centenary of the birth of modern biochemistry.

1897 was a big year for science. J. J. Thomson discovered the electron, which, along with other momentous advances around that time ushered in the golden half-century of modern physics. It was in 1897, too, that Eduard Buchner accidentally observed that yeast juice can convert sucrose to ethanol. This discovery disposed of a firm belief that alcoholic fermentation is a vital operation of an intact cell; it was the origin of modern biochemistry. Forty years of enzyme fractionation resolved this “zymase” activity into a dozen discrete reactions. With the reconstitution of alcoholic fermentation, a phenomenon that had baffled scientists for centuries was explained in molecular terms, and the stage was set for the revolutionary advances of biomedical science in the second half of our century. During the course of resolving the alcoholic fermentation in yeast juice, glycolysis by a muscle extract was also resolved into its molecular components and, astonishingly, proved to be virtually identical to the yeast pathway. Conservation of mechanisms and molecules for a billion or more years in bacteria, fungi, plants and animals has since been observed in a large number of bioenergetic and biosynthetic pathways. Universality of biochemistry represents one of the great revelations of our century. Because attention to enzymology and biochemistry has diminished in recent decades by the emergence of molecular and cellular biology, it is appropriate to be reminded of what these
On the Propagation of Extragalactic High Energy Cosmic and Gamma-Rays

The observation of air showers from elementary particles with energies exceeding 10{sup 20}thinspeV poses a puzzle to the physics and astrophysics of cosmic rays which is still unresolved. Explaining the origin and nature of these particles is a challenge. In order to constrain production mechanisms and sites, one has to account for the processing of particle spectra by interactions with radiation backgrounds and magnetic fields on the way to the observer. In this paper, I report on an extensive study on the propagation of extragalactic nucleons, {gamma}-rays, and electrons in the energy range between 10{sup 8}thinspeV and 10{sup 25}thinspeV. We have devised an efficient numerical method to solve the transport equations for cosmic ray spectral evolution. The universal radiation background spectrum in the energy range between {approx_equal}10{sup {minus}9}thinspeV and {approx_equal}10thinspeV is considered in the numerical code, including the diffuse radio background, the cosmic microwave background, and the infrared-optical background, as well as a possible extragalactic magnetic field. We apply the code to compute the particle spectra predicted by several models of ultrahigh energy cosmic ray origin. A comparison with the observed fluxes, especially the diffuse {gamma}-ray background in several energy ranges, allows one to constrain certain classes of models. {copyright}more » {ital 1998} {ital The American Physical Society}« less
Resource Exchange Seller Alliances

Many carriers, such as airlines and ocean carriers, collaborate through the formation of alliances. The detailed alliance design is clearly important for both the stability of the alliance and profitability of the alliance members. This work is motivated by a real-life liner shipping "resource exchange alliance" agreement design. We provide an economic motivation for interest in resource exchange alliances and propose a model and method to design a resource exchange alliance. The model takes into account how the alliance members compete after a resource exchange by selling substitutable products and thus enables us to obtain insight into the effect of capacity and the intensity of competition on the extent to which an alliance can provide greater profit than when in the setting without an alliance. The problem of determining the optimal amounts of resources to exchange is formulated as a stochastic mathematical program with equilibrium constraints (SMPECs). We show how to determine whether there exists a unique equilibrium after resource exchange, how to compute the equilibrium, and how to compute the optimal resource exchange. SMPEC problem, which is generally very difficult to solve, is well-posed in the paper, and robust results can be obtained with a reasonable amount of computational effort.
New Kinds of Quantum Statistics

I review the quantum kinematics of identical particles, which suggests new possibilities, beyond bosons and fermions, in 2+1 dimensions; and how simple flux-charge constructions embody the new possibilities, leading to both abelian and nonabelian anyons. I briefly allude to experimental realizations, and also advertise a spinor construction of nonabelian statistics, that has a 3+1 dimensional extension.
rpSPH: a novel smoothed particle hydrodynamics algorithm

We suggest a novel discretization of the momentum equation for smoothed particle hydrodynamics (SPH) and show that it significantly improves the accuracy of the obtained solutions. Our new formulation which we refer to as relative pressure SPH, rpSPH, evaluates the pressure force with respect to the local pressure. It respects Newton’s first law of motion and applies forces to particles only when there is a net force acting upon them. This is in contrast to standard SPH which explicitly uses Newton’s third law of motion continuously applying equal but opposite forces between particles. rpSPH does not show the unphysical particle noise, the clumping or banding instability, unphysical surface tension and unphysical scattering of different mass particles found for standard SPH. At the same time, it uses fewer computational operations and only changes a single line in existing SPH codes. We demonstrate its performance on isobaric uniform density distributions, uniform density shearing flows, the Kelvin–Helmholtz and Rayleigh–Taylor instabilities, the Sod shock tube, the Sedov–Taylor blast wave and a cosmological integration of the Santa Barbara galaxy cluster formation test. rpSPH is an improvement in these cases. The improvements come at the cost of giving up exact momentum conservation of the scheme. Consequently, one can also obtain unphysical solutions particularly at low resolutions.
Is Extreme Poverty Going to End? An Analytical Framework to Evaluate Progress in Ending Extreme Poverty

The World Bank has recently adopted a target of reducing the proportion of population living below US$1.25 a day at 2005 international prices to 3 percent by 2030. This paper reviews different projection methods and estimates the global poverty rate of 2030 modifying Ravallion (2013)'s approach in that it introduces country-specific economic and population growth rates and takes into account the effect of changes in within-country inequality. This paper then identifies key obstacles to meeting the target and proposes a simple intermediate growth target under which the global poverty rate can be reduced to 3 percent by 2030. The findings of the analysis lend support to Basu (2013)'s argument that accelerating growth is not enough and sharing prosperity within and across countries is essential to end extreme poverty in one generation.
Private and Social Incentives for Vertical Contract Disclosure

We follow the framework in Arya and Mittendorf's 2011 Rand Journal of Economics paper but extend their analysis by investigating supplier(s)' equilibrium choices of disclosure or confidentiality regarding their contract terms with the downstream retailers. In the case of a common supplier, we find that the unique subgame perfect Nash equilibrium (SPNE) is for the supplier to choose disclosure. This private incentive is opposite to social incentive, which calls for the regulator to choose confidentiality. In the case of dedicated suppliers, however, there are multiple SPNE due to coordination issues between the suppliers. The case which maximizes social surplus – disclosure – can be supported as a SPNE, together with the case of confidentiality, which maximizes supplier profits at the cost of everyone else. Copyright © 2014 John Wiley & Sons, Ltd.
Two classes of number fields with a non-principal Euclidean ideal

This paper introduces two classes of totally real quartic number fields, one of biquadratic extensions and one of cyclic extensions, each of which has a non-principal Euclidean ideal. It generalizes techniques of Graves used to prove that the number field ℚ(2,35) has a non-principal Euclidean ideal.
Satisfiability checking of non-clausal formulas using general matings

Most state-of-the-art SAT solvers are based on DPLL search and require the input formula to be in clausal form (cnf). However, typical formulas that arise in practice are non-clausal. We present a new non-clausal SAT-solver based on General Matings instead of DPLL search. Our technique is able to handle non-clausal formulas involving ∨,∧,¬ operators without destroying their structure or introducing new variables. We present techniques for performing search space pruning, learning, non-chronological backtracking in the context of a General Matings based SAT solver. Experimental results show that our SAT solver is competitive to current state-of-the-art SAT solvers on a class of non-clausal benchmarks.
Agricultural markets in Benin and Malawi : the operation and performance of traders

Drawing on original surveys of agricultural traders, the authors examine how traders operate in two Sub-Saharan African countries, Benin and Malawi. They find the following: The largest transaction costs for traders are search and transport. Search methods rely principally on personal visits by the trader, which raises search costs. And since enterprises are very small, transport represents a large share of marketing costs. Brand recognition, grading, and quality certification are nonexistent. Brokers and agents are not organized in commodity exchanges. Quantities are not pooled for transport and storage so as to achieve returns to scale. Interseasonal and interregional arbitrage is not feasible for most traders, who prefer to operate day to day in a small territory. This information provides some important insights into how agricultural trade could be improved. It suggests possible policy interventions in four main areas: increasing traders' asset base, reducing transaction risk, promoting more sophisticated business practices, and reducing physical marketing costs.
Laparoscopic liver resection: basic skills for peripheral lesions.

An evaluation of the literature demonstrates atypical wedge or single segment resections to be the most commonly performed laparoscopic liver procedures. Lesions that are both visible on the surface of segments 2-6 and ≤2-3 cm can be resected by most surgeons holding a fundamental understanding of liver anatomy. These criteria are based on the anatomical circumstance that sectoral and segmental pedicles should not course through depths necessary to obtain negative margins for these sized and positioned lesions. Videos of laparoscopic liver resections referenced in PubMed demonstrate complex procedures that are rarely performed and assume a skill set for laparoscopic dissection and transection of parenchyma and management of vascular and biliary structures. Herein is demonstrated basic skill for peripheral resections via two cases in one video, so that these procedures can be safely performed by surgeons with commonly available laparoscopic equipment.
Task scheduling on bus-based networks of workstations

In this paper, we propose a heuristic algorithm based on dynamic critical path (DCP) to solve the problem of task scheduling on networks of workstations (NOW). The algorithm takes into account both the characteristics of DCP and NOW by intelligently pre-allocating network communication resources so as to avoid potential communication conflict. It has a reasonable computational complexity of O(v2(1 + p)), where v is the number of nodes in the task graph and p is the number of processors in the NOW. It is suitable for regular as well as irregular task graphs. The algorithm when tested under various task graphs shows performance much superior to previously known techniques.
A Constrained Maximization Extension to Incremental Transfer Effectiveness, or, How To Mix Your Training Technologies

The incremental transfer effectiveness concept can be extended to a constrained maximization context by replotting the data to form a set of iso-transfer contours and adding constraints to this same graph as binding linear functions. This transformation permits an analytically elegant solution to maximizing transfer of training dynamically constrained by financial, environmental, reliability, or other restricting factors for any number of instructional technologies through application of the Lagrange Multiplier method. Alternatively, the dual problem of finding the minimum value of these constraints can be solved to achieve a specified transfer of training. An example of applying the Lagrange Multiplier method to training is provided and the potential usefulness of mathematical programming techniques noted. This extension is particularly useful in complex training environments involving numerous instructional technologies or frequently changing constraints. In the single instructional technology case, this extension provides additional graphical insight into the trade-offs involved in designing cost-effective training programs. Language: en
The dynamics of tidal tails from massive satellites

We investigate the dynamical mechanisms responsible for producing tidal tails from dwarf satellites using N-body simulations. We describe the essential dynamical mechanisms and morphological consequences of tail production in satellites with masses greater than 0.0001 of the host halo virial mass. We identify two important dynamical co-conspirators: 1) the points where the attractive force of the host halo and satellite are balanced (X-points) do not occur at equal distances from the satellite centre or at the same equipotential value for massive satellites, breaking the morphological symmetry of the leading and trailing tails; and 2) the escaped ejecta in the leading (trailing) tail continues to be decelerated (accelerated) by the satellite’s gravity leading to large offsets of the ejecta orbits from the satellite orbit. The effect of the satellite’s self gravity decreases only weakly with a decreasing ratio of satellite mass to host halo mass, proportional to (Ms/Mh) 1/3 , demonstrating the importance of these effects over a wide range of subhalo masses. Not only will the morphology of the leading and trailing tails for massive satellites be different, but the observed radial velocities of the tails will be displaced from that of the satellite orbit; both the displacement and the maximum radial velocity is proportional to satellite mass. If the tails are assumed to follow the progenitor satellite orbits, the tails from satellites with masses greater than 0.0001 of the host halo virial mass in a spherical halo will appear to indicate a flattened halo. Therefore, a constraint on the Milky Way halo shape using tidal streams requires mass-dependent modelling. Similarly, we compute the the distribution of tail orbits both in Er r 2 space (Lynden-Bell & Lynden-Bell 1995) and in E Lz space (Helmi & de Zeeuw 2000), advocated for identifying satellite stream relics. The acceleration of ejecta by a massive satellite during escape spreads the velocity distribution and obscures the signature of a well-defined “moving group” in phase space. Although these findings complicate the interpretation of stellar streams and moving groups, the intrinsic mass dependence provides additional leverage on both halo and progenitor satellite properties.
The cognitive processing of causal knowledge

There is a brief description of the probabilistic causal graph model for representing, reasoning with, and learning causal structure using Bayesian networks. It is then argued that this model is closely related to how humans reason with and learn causal structure. It is shown that studies in psychology on discounting (reasoning concerning how the presence of one cause of an effect makes another cause less probable) support the hypothesis that humans reach the same judgments as algorithms for doing inference in Bayesian networks. Next, it is shown how studies by Piaget indicate that humans learn causal structure by observing the same independencies and dependencies as those used by certain algorithms for learning the structure of a Bayesian network. Based on this indication, a subjective definition of causality is forwarded. Finally, methods for further testing the accuracy of these claims are discussed.
What Factors Predict How Public Sector Projects Perform? A Review of the World Bank's Public Sector Management Portfolio

This paper uses regression analysis to identify which country context, reform content, process, and project management variables predict the performance of public sector management projects, as measured by the Independent Evaluation Group's project outcome ratings. The paper draws on data from a large sample of World Bank public sector management projects that were approved between 1990 and 2013. It contributes to an emerging literature that uses cross-country regressions to analyze public sector management reform patterns. The findings suggest that political context factors have a greater impact on the performance of public sector management projects than on other projects. Specifically, public sector management projects perform better in countries with democratic regimes than autocratic ones. They fare better in the presence of programmatic political parties and in more aid-dependent countries. Project managers' subjective risk assessments predict performance in public sector management operations better than objective risk indicators. These findings suggest that the performance of public sector management projects would benefit from a better alignment of project design with political context and from a more open dialogue about risk between task team leaders and management.
What factors influence world literacy? is Africa different?

Ninety-five percent of the worlds illiterate people live in developing countries, and about 70 percent are women. Female illiteracy rates are particularly high in Sub-Saharan Africa. In Niger and Burkina Faso, for example, more than 90 percent of women are illiterate. This paper presents a model of literacy. It shows that the main determinants of worldwide literacy are enrollment rates, average years of schooling of adults, and life expectancy at birth. Income has a weak nonlinear effect, negatively affecting literacy until a threshold level of per-capita income of about $2200 a year is reached and positively affecting literacy thereafter. Finally, African countries do not have a significantly higher literacy rate when controlling for other factors.
Watching the aurora from Colonial America

The role of geophysics in early America is a fragmented and rarely told story. Its beginning predated the actual rise of America as a nation, and its development can be traced even through the years of the American Revolution. It seems appropriate to look back to these Colonial times to reflect, as part of science's input to the Bicentennial Year, on the great interest early Americans had in their physical environment during an era when Colonial safety and political turmoil surely dominated their everyday life. Current interest in the great sparcity of sunspots (the ‘maunder minimum’) [Frazier, 1976] which followed Galileo's telescopic verification of their existence adds yet another timely reason to discuss early American interests in solar terrestrial effects.
Connecting and resolving Sen's and Arrow's theorems

It is shown that the source of Sen's and Arrow's impossibility theorems is that Sen's Liberal condition and Arrow's IIA counter the critical assumption that voters have transitive preferences. But if the procedures are not permitted to treat the transitivity of individual preferences as a valued input, then we cannot expect rational outputs. Once this common cause for these perplexing conclusions is understood, these classical conclusions end up admitting quite benign interpretations where it becomes possible to propose several resolutions.
Wetting Transition of Water on Graphite and Other Surfaces

A wetting transition occurs when the contact angle of a liquid drop on a surface changes from a nonzero value to zero. Such a transition has never been observed for water on any solid surface. This paper discusses the value of the temperature Tw at which the transition should occur for water on graphite. A simple model, previously used for nonpolar fluids, predicts the value of Tw as a function of the well depth D of the adsorption potential. While D is not well known for the case of water/graphite, the model implies that Tw is likely to fall in the range 350−500 K. Experimental search for this transition is warranted. Water-wetting transition temperatures on other surfaces are also discussed.
The decomposability problem for torsion-free abelian groups is analytic-complete

We discuss the decomposability of torsion-free abelian groups. We show that among computable groups of finite rank this property is $\Sigma^0_3$-complete. However, when we consider groups of infinite rank, it becomes $\Sigma^1_1$-complete, so it cannot be characterized by a first-order formula in the language of arithmetic.
Relations on generalized degree sequences

We study degree sequences for simplicial posets and polyhedral complexes, generalizing the well-studied graphical degree sequences. Here we extend the more common generalization of vertex-to-facet degree sequences by considering arbitrary face-to-flag degree sequences. In particular, these may be viewed as natural refinements of the flag f-vector of the poset. We investigate properties and relations of these generalized degree sequences, proving linear relations between flag degree sequences in terms of the composition of rank jumps of the flag. As a corollary, we recover an f-vector inequality on simplicial posets first shown by Stanley.
Khovanov-Rozansky homology and the braid index of a knot

We construct a knot whose braid index is not detected by the Morton-Franks-Williams (MFW) inequality but is detected by a related KR-MFW inequality that comes from the Khovanov-Rozansky homology. We also construct infinitely many knots whose braid indices are not detected by the KR-MFW inequality.
Enhancement of two-dimensional echocardiographic images by lateral filtering

Abstract A digital filtering technique has been developed for enhancement of two-dimensional ultrasonic images of the heart. The filtering is applied to the lateral axis normal to the direction of scanlines. The enhancement results from both filtering off-axis artifacts and interpolation within the scanning plane. Simple filters of this design have been implemented which significantly increase the quality of images. Theoretical considerations for development of such filters is also discussed.
Impurity effects in d-wave superconductors.

It is well documented that substitution of Cu in the Cu-O2 plane by Zn has dramatic effects on the superconducting properties of high Tc cuprates. Assuming that Zn introduces nonmagnetic impurities in the unitarity limit, we study the electron density of states, static spin susceptibility and other properties systematically. In particular we find that our density of states describes quite well the one observed in Bi2Sr2CaCu2Ox by Barbiellini et al. Further the knight shift in 1% and 2% Zn substituted YBa2Cu3O7 observed by Ishida et al. is well described by the present model.
Nanophotonic computational design

In contrast to designing nanophotonic devices by tuning a handful of device parameters, we have developed a computational method which utilizes the full parameter space to design linear nanophotonic devices. We show that our method may indeed be capable of designing any linear nanophotonic device by demonstrating designed structures which are fully three-dimensional and multi-modal, exhibit novel functionality, have very compact footprints, exhibit high efficiency, and are manufacturable. In addition, we also demonstrate the ability to produce structures which are strongly robust to wavelength and temperature shift, as well as fabrication error. Critically, we show that our method does not require the user to be a nanophotonic expert or to perform any manual tuning. Instead, we are able to design devices solely based on the user's desired performance specification for the device.
Quadtree classification and TCQ image coding

The set partitioning in hierarchical trees (SPIHT) wavelet image coding algorithm can be interpreted as implicitly using classification in its bit-plane coding procedure. The source distribution induced by this classification is studied and rate-distortion performance is evaluated. A quadtree sorting procedure, similar to SPIHT, is used to explicitly form classes of wavelet coefficients. The classes are encoded using arithmetic and trellis-coded quantization. The resulting encoding algorithm offers consistent improvement over SPIHT performance due to the granular gain of the trellis code.
Time-Resolved Microwave Conductivity

The pump-probe Time-Resolved Microwave Conductivity technique under pulsed laser excitation is increasingly being used to study the photophysics of nanostructured photovoltaics. Its principles of operation and applications to various material systems will be discussed.
Mantle circulation models with variational data assimilation: inferring past mantle flow and structure from plate motion histories and seismic tomography

SUMMARY Mantle convection models require an initial condition some time in the past. Because this initial condition is unknown for Earth, we cannot infer the geological evolution of mantle flow from forward mantle convection calculations even for the most recent Mesozoic and Cenozoic geological history of our planet. Here we introduce a fluid dynamic inverse problem to constrain unknown mantle flow back in time from seismic tomographic observations of the mantle and reconstructions of past plate motions using variational data assimilation. We derive the generalized inverse of mantle convection and explore the initial condition problem in high-resolution, 3-D spherical mantle circulation models for a time period of 100 Myr, roughly comparable to half a mantle overturn. We present a synthetic modelling experiment to demonstrate that mid-Cretaceous mantle structure can be inferred accurately from fluid dynamic inverse modelling, assuming present-day mantle structure is well-known, even if an initial first guess assumption about the mid-Cretaceous mantle involved only a simple 1-D radial temperature profile. We also demonstrate that convecting present-day mantle structure back in time by reversing the time-stepping of the energy equation is insufficient to model the mantle structure of the past. The difficulty arises, because such backward convection calculations ignore thermal diffusion effects, and therefore cannot account for the generation of thermal buoyancy in boundary layers as we go back in time. Inverse mantle convection modelling should make it possible to infer a number of flow parameters from observational constraints of the mantle.
N-Ethylazatribenzo-21-crown-7

The structure of the title compound, 25-ethyl-2,5,12,15,22,28-hexa­oxa-25-aza­tetra­cyclo­[27.4.0.06,11.016,21]­tri­tria­conta-1(29),6(11),7,9,16(21),17,19,30,32-nona­ene, C28H33NO6, does not exhibit a binding cavity for cations, but is collapsed in on itself. The conformation is unique among known tri­benzo-21-crown-7 structures, and may be a result of intermolecular (C—H⋯π) and intramolecular (C—H⋯O) hydrogen bonding.
Riesz s-Equilibrium Measures on d-Rectifiable Sets as s Approaches d

Let A be a compact set in \({\mathbb R}^{p}\) of Hausdorff dimension d. For s ∈ (0,d) the Riesz s-equilibrium measure μs is the unique Borel probability measure with support in A that minimizes $$ {I_s}(\mu):=\int\int{\frac{1}{{|{x} - {y}|}^{s}}}d\mu(y)d\mu(x) $$ over all such probability measures. If A is strongly \(({\mathcal H}^d, d\kern.5pt)\)-rectifiable, then μs converges in the weak-star topology to normalized d-dimensional Hausdorff measure restricted to A as s approaches d from below.
Cytotoxic compounds from invasive giant salvinia (Salvinia molesta) against human tumor cells.

Abstract Giant salvinia ( Salvinia molesta ) is one of the most noxious invasive species in the world. Our bioactivity-guided fractionation of ethanol extract of giant salvinia led to the isolation of 50 compounds. Of the six new compounds ( 1 – 6 ), salviniol ( 1 ) is a rare abietane diterpene with a new ferruginol-menthol coupled skeleton and both salviniside I ( 2 ) and salviniside II ( 3 ) are novel benzofuran glucose conjugates with unique 10-membered macrodiolide structures. Sixteen abietane diterpenes ( 1 , 7 – 17 , and 19 – 22 ) demonstrated in vitro activities against human tumor cells, and 7 and 8 showed selective cytotoxicity to tumor cells over normal cells.
Cost-effective ways of improving database computer performance

In this paper the hardware features that characterize the performance bottlenecks of conventional database computers are identified. Motivations for and proposals of new architectures for overcoming the bottlenecks for future database computers are given.
Recent advances in solar cell technology

The advances in solar cell efficiency, radiation tolerance, and cost over the last decade are reviewed. Potential performance of thin-film solar cells in space are discussed, and the cost and the historical trends in production capability of the photovoltaics industry are considered with respect to the requirements of space power systems. Concentrator cells with conversion efficiency over 30%, and nonconcentrating solar cells with efficiency over 25% are now available, and advanced radiation-tolerant cells and lightweight, thin-film arrays are both being developed. Nonsolar applications of solar cells, including thermophotovoltaics, alpha- and betavoltaics, and laser power receivers, are also discussed.
A maximal inequality for supermartingales

A tight upper bound is given on the distribution of the maximum of a supermartingale. Specifically, it is shown that if $Y$ is a semimartingale with initial value zero and quadratic variation process $[Y,Y]$ such that $Y + [Y,Y]$ is a supermartingale, then the probability the maximum of $Y$ is greater than or equal to a positive constant $a$ is less than or equal to$1/(1+a).$ The proof makes use of the semimartingale calculus and is inspired by dynamic programming.
Synthesis of N,N′‐bis(2‐Thiazolinyl)‐, N,N′‐bis(2‐Thiazolyl)‐, and N,N′‐bis(2‐Pyrimidinyl)‐Benzene Dicarboxamides

Abstract New heteroaromatic benzene dicarboxamides have been synthesized in moderate to good yields by the reactions of 2‐aminothiazoline, 2‐aminothiazole, and 2‐aminopyrimidine with phthaloyl dichloride, isophthaloyl dichloride, and terephthaloyl dichloride in the presence of an organic base. The amides are sparingly soluble in common organic solvents but dissolve readily in dimethyl sulfoxide. Reactions of 2‐aminothiazoline and 2‐aminopyrimidine with phthaloyl dichloride yield a tricyclic compound and an imide, respectively, instead of the expected products.
Protumor immunity and breast cancer development

For decades, it was generally accepted that leukocytic infiltrations in tumors represented a failed attempt of the immune system to eradicate damaged cells. While indeed some aspects of failed anti-tumor immunity exist, what we now appreciate is the fact that multiple protumor immune programs are instead co-opted by nascent tumors, and in so doing significantly enhance tumor development, including breast cancer. Based upon our evaluation of human clinical specimens revealing significant infiltration of breast tumor tissue by both T lymphocytes and macrophages, we asked the question as to whether adaptive immunity was perhaps enhancing protumor properties of macrophages and thereby potentiating breast carcinogenesis. Utilizing the MMTV-PyMT mouse model of mammary carcinogenesis, CD4+ T cell-deficient mice, and an ex vivo three-dimensional organoid co-culture model, we revealed a tumor-promoting role for TH2-CD4+ T effector cells that elicit pro-tumor, as opposed to cytotoxic, bioactivities of tumor-associated macrophages (TAMs) and enhancement of pro-metastatic epidermal growth factor (EGF) receptor signaling programs in malignant mammary epithelial cells. These novel findings provide a mechanism explaining how TH2-activated TAMs achieve HIGH level expression of EGF necessary for inducing survival, invasive growth and metastatic programs in malignant cells, and together indicate that anti-tumor acquired immunity, mediated by CD4+ T lymphocytes are usurped in pro-tumor microenvironments and instead promote cancer by engaging cellular components of the innate immune system, and identifies new cellular targets, namely TH2-polarized CD4+ T lymphocytes, for anti-cancer therapy.
Marital Disruption and Health Insurance

Despite the high levels of marital disruption in the United States and the fact that a significant portion of health insurance coverage for those less than age 65 is based on family membership, surprisingly little research is available on the consequences of marital disruption for the health insurance coverage of men, women, and children. We address this shortfall by examining patterns of coverage surrounding marital disruption for men, women, and children, further subset by educational level. Using the 1996, 2001, and 2004 panels of the Survey of Income and Program Participation (SIPP), we find large differences in health insurance coverage across marital status groups in the cross-section. In longitudinal analyses that focus on within-person change, we find small overall coverage changes but large changes in type of coverage following marital disruption. Both men and women show increases in private coverage in their own names, but offsetting decreases in dependent coverage tend to be larger. One surprising result is that dependent coverage for children also declines after marital dissolution, even though children are still likely to be eligible for that coverage. Children and (to a lesser extent) women show increases in public coverage around the time of divorce or separation. We also find that these patterns differ by education. The most vulnerable group appears to be lower-educated women with children because the increases in private, own-name, and public insurance are not large enough to offset the large decrease in dependent coverage. As the United States implements federal health reform, it is critical that we understand the ways in which life course events—specifically, marital disruption—shape the dynamic patterns of coverage.
Dual loop terms and counterterms by means of their projective group

Abstract A unified treatment of dual loop term and counterterm by means of their projective group is presented for the one loop case. The significance of parameters in this method of linear differential equations is discussed for multi loop terms.
Finite width effects in top quark decays

Abstract Motivated by evidence that the top quark mass lies near the b WZ threshold, we compute the decay rate for t → b WZ in the Standard Model, including the effects of the finite widths of the W and Z bosons. In the limit where the width effects are negligible, our results disagree with previously published calculations. We also examine the decay t → b WH. Although the widths induce a sizable enhancement near threshold for both decays, we find that the rates are still too small to be observed in the present generation of experiments. This means that detection of either mode in one of these experiments would be a signal of new physics.
Black–white differences in beliefs about the U.S. restaurant tipping norm: Moderated by socio-economic status?

Abstract A re-analysis of two national telephone surveys found that black–white differences in awareness that it is customary to tip a percentage of the bill declined as socio-economic status increased. However, black–white differences in awareness that is customary to tip 15–20 percent in restaurants was unrelated to socio-economic status. The practical as well as theoretical implications of these findings are discussed along with directions for future research.
Arms Races and Negotiations

Two players simultaneously decide whether or not to acquire new weapons in an arms race game. Each player's type determines his propensity to arm. Types are private information, and are independently drawn from a continuous distribution. With probability close to one, the best outcome for each player is for neither to acquire new weapons (although each prefers to acquire new weapons if he thinks the opponent will). There is a small probability that a player is a dominant strategy type who always prefers to acquire new weapons. We find conditions under which the unique Bayesian-Nash equilibrium involves an arms race with probability one. However, if the probability that a player is a dominant strategy type is sufficiently small, then there is an equilibrium of the cheap-talk extension of the game where the probability of an arms race is close to zero. Copyright 2004, Wiley-Blackwell.
Are the Variations in Quasar Optical Flux Driven by Thermal Fluctuations

We analyze a sample of optical light curves for 100 quasars, 70 of which have black hole mass estimates. Our sample is the largest and broadest used yet for modeling quasar variability. The sources in our sample have z < 2.8, 1042 λL λ(5100 A) 1046, and 106 M BH/M ☉ 1010. We model the light curves as a continuous time stochastic process, providing a natural means of estimating the characteristic timescale and amplitude of quasar variations. We employ a Bayesian approach to estimate the characteristic timescale and amplitude of flux variations; our approach is not affected by biases introduced from discrete sampling effects. We find that the characteristic timescales strongly correlate with black hole mass and luminosity, and are consistent with disk orbital or thermal timescales. In addition, the amplitude of short-timescale variations is significantly anticorrelated with black hole mass and luminosity. We interpret the optical flux fluctuations as resulting from thermal fluctuations that are driven by an underlying stochastic process, such as a turbulent magnetic field. In addition, the intranight variations in optical flux implied by our empirical model are 0.02 mag, consistent with current microvariability observations of radio-quiet quasars. Our stochastic model is therefore able to unify both long- and short-timescale optical variations in radio-quiet quasars as resulting from the same underlying process, while radio-loud quasars have an additional variability component that operates on timescales 1 day.
Resettable vector clocks

Vector clocks (VC) are an inherent component of a rich class of distributed applications. In this paper, we first consider the problem of realistic implementation-more specifically, bounded-space and fault-tolerant-of applications that use vector clocks (VC). To this end, we generalize the notion of VC to resettable vector clocks (RVC), and provide a realistic implementation of RVC. Further, we identify an interface contract under which our RVC implementation can be substituted for VC in client applications, without affecting the client's correctness. This interface contract is designed for phase-based applications that provide certain communication guarantees. Based on such substitution and the use of the interface contract, we show how to transform the client so that it is itself realistically implemented. We illustrate our method in the context of Ricart-Agrawala's mutual exclusion program and Garg-Chase's predicate detection program.
Hodge duality on the brane

Abstract It has been claimed that whereas scalars can be bound to a Randall–Sundrum brane, higher p -form potentials cannot, in contradiction with the Hodge duality between 0-form and 3-form potentials in the five-dimensional bulk. Here we show that a 3-form in the bulk correctly yields a 2-form on the brane, in complete agreement with both bulk and brane duality. We also emphasize that the phenomenon of photon screening in the Randall–Sundrum geometry is ruled out by the bulk Einstein equation.
Knowledge-Based Systems for Design

Knowledge-based systems are a special class of computer programs that purport to perform, or to assist humans in performing, specified intellectual tasks. This paper describes how knowledge-based programs are special ; that is, how they differ from other computer programs. A structure for understanding the use of knowledge-based programs in engineering design is presented, together with an example. The role of knowledge-based systems in design research is discussed.
Evolutionary game theory on measure spaces: Well-posedness

Abstract An attempt is made to find a comprehensive mathematical framework in which to investigate the problems of well-posedness and asymptotic analysis for fully nonlinear evolutionary game theoretic models. The model should be rich enough to include all classical nonlinearities, e.g., Beverton–Holt or Ricker type. For several such models formulated on the space of integrable functions, it is known that as the variance of the payoff kernel becomes small the solution converges in the long term to a Dirac measure centered at the fittest strategy; thus the limit of the solution is not in the state space of integrable functions. Starting with the replicator–mutator equation and a generalized logistic equation as bases, a general model is formulated as a dynamical system on the state space of finite signed measures. Well-posedness is established, and then it is shown that by choosing appropriate payoff kernels this model includes all classical density models, both selection and mutation, and discrete and continuous strategy (trait) spaces.
Physiology, histology, and 2-week morphology of acute transmyocardial channels made with a CO2 laser

Background. Transmyocardial revascularization with a CO 2 laser appears to improve symptoms in patients with refractory angina. However, it remains controversial as to whether blood flow through the channels is the mechanism of benefit, especially in the acute setting. Methods and Results. Three protocols were used to test whether blood flows through transmyocardial CO 2 laser revascularization channels. First, channels were made in excised, cross-perfused dog hearts (n = 5) using a CO 2 laser (The Heart Laser; PLC Systems Inc, Milford, MA; 40 J/pulse) followed by ligation of the proximal left anterior descending coronary artery. Colored microspheres injected into the left ventricular chamber failed to detect any significant transmyocardial blood flow. In the second protocol (n = 4), laser channels were created in the left anterior descending artery territory, the left anterior descending artery was ligated, and the hearts were excised after 24 hours. Triphenyltetrazolium chloride staining revealed that no viable myocardium was detected around the laser channels in the ischemic myocardium. Finally, channels examined 2 weeks after creation in normal (n = 6) or ischemic (n = 4) myocardium did not maintain their original caliber but were invaded by granulation tissue, which included a large amount of smaller vascular spaces and vessels of various sizes. Conclusions. Transmyocardial laser revascularization channels made with this CO 2 laser did not provide acute myocardial perfusion or preserve myocardial viability in the face of acute ischemia. Channel morphology changes dramatically within the first 2 weeks. To the degree that these findings pertain to human myocardium, the results suggest that transmyocardial blood flow may not be the mechanism of benefit of this procedure, particularly in the acute setting.
Stress Corrosion of Ionic and Mixed Ionic/Covalent Solids

Slow crack growth data, surface reaction studies, and solubility results for sapphire and magnesium fluoride crystals are used to identify stress corrosion mechanisms for each material. Results suggest that stress corrosion in sapphire proceeds by the dissociative chemisorption of environmental species on strained crack tip bonds. Crack growth rates measured in nonaqueous environments and isotopically labeled water suggest that ion solvation rather than dissociative chemisorption dominates the crack tip interaction in magnesium fluoride.
The process of technology transfer to the new biomedical and pharmaceutical firm

Abstract This paper applies the theories of technological innovation to the process of technology transfer to biomedical and pharmaceutical start-ups. It is based on detailed data gathered from 26 firms, founded between 1968 and 1975 in the Commonwealth of Massachusetts. The routes of technology transfer were traced, and the comparative impact of entrepreneurial professional experience, and the continuous flow of information to the firm were evaluated. In this context, the dominant role of the hospital and the medical school were elicited. Even weak contacts with universities and hospitals were found conducive to transferring technology from research to industry, enhancing technological innovativeness of the young biomedical firm. On the other hand the relation between technological attributes and economic success of the biomedical firm is more complex: (a) contacts with the clinical environment do not significantly facilitate its economic performance; (b) technological sophistication and advancedness of firm's products are not dominant factors in determining its economic success.
The impact of the Droit de Suite in the UK: an empirical analysis

The Droit de Suite, known in the UK as Artists’ Resale Rights, provides an artist with the inalienable right to receive a royalty based on the resale price of an original work of art. This paper provides an empirical analysis of actual changes in the UK auction market for art that is newly subject to the Droit de Suite (DDS) because of a change in law. All changes are measured relative to changes for art not subject to the DDS and relative to changes in the auction markets for art in countries where there has been no change in law. We do a difference-in-difference analysis, differencing price growth and sales growth across market segments and across countries over the period 1993–2007. Our results suggest that the introduction of the DDS has not had a consistent negative impact on the UK art auction market during the period of study.