cssi/SciSciGPT-SciSciNet huggingface dataset:
The UV-FEL at the NSLS: straight injection configuration

We present a design of a collinear RF-photocathode gun and linac sections for the ultraviolet free-electron laser under study at the National Synchrotron Light Source. An inverse Helmholtz solenoid pair is used to control the divergence of the electron beam and present a slightly convergent and small beam into a conventional SLAC linac. The relative distance of the gun to the linac and the strength of the solenoidal held are chosen to minimize the emittance growth of the beam due to space charge. The simulation codes PARMELA and TRACE-3D are used to model the beam from the cathode to the entrance to the wiggler. >
Orthogonal ligation strategies for peptide and protein.

This review focuses on the concept, criteria, and methods of an orthogonal amide ligating strategy suitable for syntheses of peptides, peptide mimetics, and proteins. Utilizing unprotected peptides or proteins derived from chemical or biosynthetic sources, this ligation strategy has been shown to be general and exceptionally mild. Its orthogonality in ligating two unprotected segments with free N-terminal (NT)-amines at a specific NT-amine is achieved through a chemoselective capture step and then an intramolecular acyl transfer reaction. Both coupling reagents for enthalpic activation and protection schemes therefore become unnecessary. More than a dozen orthogonal ligation methods based on either imine or thioester captures have been developed to afford native and unusual amino acids at ligation sites of linear, branched, or cyclic peptides. Because unprotected peptides and proteins of different sizes and forms can be obtained from either chemical or recombinant sources, orthogonal ligation removes the size limitation imposed on the chemical synthesis of a protein with a native or non-native structure. Furthermore, by using building blocks from biosynthetic sources, orthogonal ligation provides a unifying operational concept for both total and semisynthesis of peptides and proteins. © 2000 John Wiley & Sons, Inc. Biopoly 51: 311–332, 1999
A STOCHASTIC APPROACH TO SENTENCE PARSING

A description will be given of a procedure to assign the most likely probabilities to each of the rules of a given context-free grammar. The grammar developed by S. Kuno at Harvard University was picked as the basis and was successfully augmented with rule probabilities. A brief exposition of the method with some preliminary results, when used as a device for disambiguating parsing English texts picked from natural corpus, will be given.
Enzymatic preparation of (3S,6R) and (3R,6S)-3-hydroxy-6-acetoxycyclohex-1-ene

Pseudomonas cepacia lipase-catalyzed enantioselective hydrolysis of 2 in water afforded (3S,6R)-3. The antipode (3R,6S)-3 was prepared by enantioselective acylation of 4 using the same enzyme.
Accounting for the Effect Of Health on Economic Growth

I use microeconomic estimates of the effect of health on individual outcomes to construct macroeconomic estimates of the proximate effect of health on GDP per capita. I employ a variety of methods to construct estimates of the return to health, which I combine with cross-country and historical data on height, adult survival rates, and age at menarche. Using my preferred estimate, eliminating health differences among countries would reduce the variance of log GDP per worker by 9.9 percent and reduce the ratio of GDP per worker at the 90th percentile to GDP per worker at the lOth percentile from 20.5 to 17.9. While this effect is economically significant, it is also substantially smaller than estimates of the effect of health on economic growth that are derived from cross-country regressions.
Optimal quality threshold of admission in a two-sided farmers’ market

We develop a two-sided model for a farmers’ market where farmers value the number of consumers, and consumers value the number of farmers and the average product quality in the market. Consumer preference over product quality provides an incentive for the farmers’ market to exclude farmers of the lowest product quality. Using the model, we identify what factors the farmers’ market has to consider in determining the optimal quality threshold of admission, an issue that has not received any formal study. Those factors include the network effects between farmers and consumers, consumer preference over product quality and variety, and the quality spread among farmers. We also outline an empirical estimation strategy in order to make use of the model developed in this study.
Rerandomizable RCCA encryption

We give the first perfectly rerandomizable, Replayable-CCA (RCCA) secure encryption scheme, positively answering an open problem of Canetti et al. (CRYPTO 2003). Our encryption scheme, which we call the Double-strand Cramer-Shoup scheme, is a non-trivial extension of the popular Cramer-Shoup encryption. Its security is based on the standard DDH assumption. To justify our definitions, we define a powerful "Replayable Message Posting" functionality in the Universally Composable (UC) framework, and show that any encryption scheme that satisfies our definitions of rerandomizability and RCCA security is a UC-secure implementation of this functionality. Finally, we enhance the notion of rerandomizable RCCA security by adding a receiver-anonymity (or key-privacy) requirement, and show that it results in a correspondingly enhanced UC functionality. We leave open the problem of constructing a scheme achieving this enhancement.
Loop Equations and the Topological Phase of Multi-Cut Matrix Models

We study the double scaling limit of mKdV type, realized in the two-cut Hermitian matrix model. Building on the work of Periwal and Shevitz and of Nappi, we find an exact solution including all odd scaling operators, in terms of a hierarchy of flows of 2×2 matrices. We derive from it loop equations which can be expressed as Virasoro constraints on the partition function. We discover a “pure topological” phase of the theory in which all correlation functions are determined by recursion relations. We also examine macroscopic loop amplitudes, which suggest a relation to 2D gravity coupled to dense polymers.
Relational contracts with and between agents

We study a dynamic multi-agent model with a verifiable team performance measure and non-verifiable individual measures. The optimal contract can be interpreted as an explicit contract that specifies a minimum bonus pool as a function of the verifiable measure and an implicit contract that gives the principal discretion to increase the size of the pool and to allocate it among the agents. To mitigate the threat of collusion, the optimal contract often converts any exogenous productive interdependence into strategic payoff independence for the agents. Under productive complements, an unconditional bonus pool (pay without performance) can be less costly than one conditioned on the verifiable team measure.
Radial fingering in a Hele-Shaw cell: a weakly nonlinear analysis

Abstract The Saffman-Taylor viscous fingering instability occurs when a less viscous fluid displaces a more viscous one between narrowly spaced parallel plates in a Hele-Shaw cell. Experiments in radial flow geometry form fan-like patterns, in which fingers of different lengths compete, spread and split. Our weakly nonlinear analysis of the instability predicts these phenomena, which are beyond the scope of linear stability theory. Finger competition arises through enhanced growth of sub-harmonic perturbations, while spreading and splitting occur through the growth of harmonic modes. Nonlinear mode-coupling enhances the growth of these specific perturbations with appropriate relative phases, as we demonstrate through a symmetry analysis of the mode coupling equations. We contrast mode coupling in radial flow with rectangular flow geometry.
Acquisition of Motor Skills: Information Processing Differences between Children and Adults

(1980). Acquisition of Motor Skills: Information Processing Differences between Children and Adults. Research Quarterly for Exercise and Sport: Vol. 51, No. 1, pp. 158-173.
Density-functional study of adsorption of isocyanides on the gold (111) surface

Density functional theory within the generalized-gradient approximation is used to study the adsorption of the isocyanides CNH and CNCH3 on the gold (111) surface at several coverages. It is found that these molecules are highly selective in their adsorption site preference. Adsorption is possible only at the top site, although binding is rather weak and dipole−dipole repulsion prevents binding at coverages of 1/3 ML and higher. At all other high-symmetry sites considered (hexagonal close-packed, face-centered cubic, bridge), the isocyanides are not bound. To reveal the main mechanisms of bonding, the isocyanides are compared to CO and ammonia using Au−X radicals as model systems. The systematic trends are understood in terms of σ donation from the ligand lone pair and π* back-donation. Finally, CNH is found to be more strongly bound to an undercoordinated gold atom (adatom) on the surface.
P-Selective Sets, Tally Languages, and the Behavior of Polynomial Time Reducibilities on NP

The notion of p-selective sets, and tally languages, are used to study polynomial time reducibilities on NP. P-selectivity has the property that a set A belongs to the class P if and only if both Ā ≤ m P A and A is p-selective. We prove that for every tally language set in NP there exists a polynomial time equivalent set in NP that is p-selective. From this result it follows that if NEXT ≠ DEXT, then polynomial time Turing and many-one reducibilities differ on NP.
The Revenues and Expenditures of African Governments: Modalities and Consequences

Like governments elsewhere, African governments raise revenues, employ workers and make expenditures. They do so in ways that reflect and affect the structure of their economies. Important interdependencies exist among revenues, employment and expenditures, and in more ways than the obvious one that expenditures have to be funded and require employees for implementation. Considerations include: the dependence of government revenues on export prices; the unimportance of the personal income tax; government wages relative to private sector opportunities; the role of education in altering the supply of government workers and their wages; and the effect of government expenditures on government revenues. Copyright 1996 by Oxford University Press.
A direct route to the pyrrolo[2,1-c][1,4]benzodiazepine ring system using aryl triflates

Abstract The pyrrolo[2,1-c][1,4]benzodiazepine and dibenzo[b,e][1,4]diazepine skeletons were rapidly generated from salicylic acids. The key step in these syntheses was the substitution of an aryl triflate.
Cross-Border Investing with Tax Arbitrage: The Case of German Dividend Tax Credits

German dividends typically carry a tax credit which makes the dividend worth 42.86% more to a taxable German shareholder than to a tax-exempt or foreign shareholder. This results in a penalty for foreign investors who buy and hold German dividend-paying stocks. I document that, as a result of the credit, the ex-day drop exceeds the dividend by more than one-half of the tax credit, and show that futures and option prices embed more than one-half of the tax credit. The existence of the credit creates opportunities for cross-border tax arbitrage—in which foreign holders of German stock transfer the dividend to German shareholders—and implies that it is tax efficient for foreign investors to hold derivatives rather than investing directly in German stocks. The empirical findings are consistent with costly tax arbitrage activity by German investors, who face tax risk due to antiarbitrage rules. Since dividend tax credits exist in many other countries, the findings are potentially of broad interest.
The application of posicast control to DC-DC converters

Analysis, design and simulation of a Posicast-based controller are presented for both buck and boost converters. Posicast is a feedforward compensator, which eliminates the overshoot in the step response of lightly damped systems. However, the traditional method is sensitive to variations in natural frequency. The new method described here reduces this undesirable sensitivity by using Posicast within the feedback loop. Design of the Posicast function is independent of computational delay. Compared to a PID controller, the new controller results in a lower noise in the control signal. Furthermore, for the boost converter, the unfavorable effect on system stability caused by RHP zero of the model can be neglected in the design of controller. The performance of Posicast-based controllers for both buck and boost converters has been investigated through simulations using SIMULINK.
Nearly Maximum Flows in Nearly Linear Time

We introduce a new approach to the maximum flow problem in undirected, capacitated graphs using congestion-approximators: easy-to-compute functions that approximate the congestion required to route single-commodity demands in a graph to within some factor α. Our algorithm maintains an arbitrary flow that may have some residual excess and deficits, while taking steps to minimize a potential function measuring the congestion of the current flow plus an over-estimate of the congestion required to route the residual demand. Since the residual term over-estimates, the descent process gradually moves the contribution to our potential function from the residual term to the congestion term, eventually achieving a flow routing the desired demands with nearly minimal congestion after O(α2e-2 log2 n) iterations. Our approach is similar in spirit to that used by Spielman and Teng (STOC 2004) for solving Laplacian systems, and we summarize our approach as trying to do for l∞-flows what they do for l∞-flows. Together with a nearly linear time construction of a no(1)-congestion-approximator, we obtain 1 + e-optimal singlecommodity flows undirected graphs in time m1+o(1)e-2, yielding the fastest known algorithm for that problem. Our requirements of a congestion-approximator are quite low, suggesting even faster and simpler algorithms for certain classes of graphs. For example, an α-competitive oblivious routing tree meets our definition, even without knowing how to route the tree back in the graph. For graphs of conductance φ, a trivial φ-1-congestionapproximator gives an extremely simple algorithm for finding O(mφ-1).
Information and the hold‐up problem

We examine situations in which a party must make a sunk investment prior to contracting with a second party to purchase an essential complementary input. We study how the resulting hold-up problem is affected by the seller’s information about the investing party’s likely returns from its investment. Our principal focus is on the effects of the investment’s being observable by the non-investing party. Contrary to popular intuition, we find that an improvement in the seller’s information (e.g., the investment’s being observable rather than not) can benefit the buyer and harm the seller. We also find that other popular intuitions about this problem are either false, incomplete, or require strong assumptions to be valid.
Gating of high-mobility InAs metamorphic heterostructures

We investigate the performance of gate-defined devices fabricated on high mobility InAs metamorphic heterostructures. We find that heterostructures capped with In0.75Ga0.25As often show signs of parallel conduction due to proximity of their surface Fermi level to the conduction band minimum. Here, we introduce a technique that can be used to estimate the density of this surface charge that involves cool-downs from room temperature under gate bias. We have been able to remove the parallel conduction under high positive bias, but achieving full depletion has proven difficult. We find that by using In0.75Al0.25As as the barrier without an In0.75Ga0.25As capping, a drastic reduction in parallel conduction can be achieved. Our studies show that this does not change the transport properties of the quantum well significantly. We achieved full depletion in InAlAs capped heterostructures with non-hysteretic gating response suitable for fabrication of gate-defined mesoscopic devices.
Parimutuel Betting on Permutations

We focus on a permutation betting market under parimutuel call auction model where traders bet on final rankings of n candidates. We present a Proportional Betting mechanism for this market. Our mechanism allows traders to bet on any subset of the n 2 `candidate-rank' pairs, and rewards them proportionally to the number of pairs that appear in the final outcome. We show that market organizer's decision problem for this mechanism can be formulated as a convex program of polynomial size. Further, the formulation yields a set of n 2 unique marginal prices that are sufficient to price the bets in this mechanism, and are computable in polynomial-time. These marginal prices reflect the traders' beliefs about the marginal distributions over outcomes. More importantly, we propose techniques to compute the joint distribution over n ! permutations from these marginal distributions. We show that using a maximum entropy criterion, we can obtain a concise parametric form (with only n 2 parameters) for the joint distribution which is defined over an exponentially large state space. We then present an approximation algorithm for computing the parameters of this distribution. In fact, our algorithm addresses a generic problem of finding the maximum entropy distribution over permutations that has a given mean, and is of independent interest.
User-Friendly Tail Bounds for Sums of Random Matrices

This paper presents new probability inequalities for sums of independent, random, self-adjoint matrices. These results place simple and easily verifiable hypotheses on the summands, and they deliver strong conclusions about the large-deviation behavior of the maximum eigenvalue of the sum. Tail bounds for the norm of a sum of random rectangular matrices follow as an immediate corollary. The proof techniques also yield some information about matrix-valued martingales. In other words, this paper provides noncommutative generalizations of the classical bounds associated with the names Azuma, Bennett, Bernstein, Chernoff, Hoeffding, and McDiarmid. The matrix inequalities promise the same diversity of application, ease of use, and strength of conclusion that have made the scalar inequalities so valuable.
Inductive magnetosphere-ionosphere coupling

Abstract Inductive coupling of a global magnetospheric model to a global ionospheric–thermospheric model is described. Existing schemes based on electrostatic coupling are valid for magnetospheric variability occurring on time scales of order 100 s or longer. The formulation developed here extends the validity of the coupling model to time scales of order 10 s, while retaining the physics of quasi-static coupling as the long time-scale limit. Both lumped and distributed formulations for the coupling region are derived. The induction gives rise to magnetic and ion kinetic energy storage at low altitude. The induced ion polarization current on average causes an upward magnetic body force on the plasma which may facilitate massive outflow.
The overconvergent Shimura lifting

We construct a rigid analytic map from the half-integral weight cuspidal eigencurve to its integral weight counterpart that interpolates the classical Shimura lifting.
Off-Center Collisions between Clusters of Galaxies

We present numerical simulations of off-center collisions between galaxy clusters made using a new hydrodynamical code based on the piecewise-parabolic method (PPM) and an isolated multigrid potential solver. The current simulations follow only the intracluster gas. We have performed three high-resolution (256 × 1282) simulations of collisions between equal-mass clusters using a nonuniform grid with different values of the impact parameter (0, 5, and 10 times the cluster core radius). Using these simulations, we have studied the variation in equilibration time, luminosity enhancement during the collision, and structure of the merger remnant with varying impact parameter. We find that in off-center collisions the cluster cores (the inner regions where the pressure exceeds the ram pressure) behave quite differently from the clusters' outer regions. A strong, roughly ellipsoidal shock front, similar to that noted in previous simulations of head-on collisions, enables the cores to become bound to each other by dissipating their kinetic energy as heat in the surrounding gas. These cores survive well into the collision, dissipating their orbital angular momentum via spiral bow shocks. After the ellipsoidal shock has passed well outside the interaction region, the material left in its wake falls back onto the merger remnant formed through the inspiral of the cluster cores, creating a roughly spherical accretion shock. For less than one-half of a sound crossing time after the cores first interact, the total X-ray luminosity increases by a large factor; the magnitude of this increase depends sensitively on the size of the impact parameter. Observational evidence of the ongoing collision, in the form of bimodality and distortion in projected X-ray surface brightness and temperature maps, is present for one to two sound crossing times after the collision but only for special viewing angles. The remnant actually requires at least five crossing times to reach virial equilibrium. Since the sound crossing time can be as large as 1-2 Gyr, the equilibration time can thus be a substantial fraction of the age of the universe. The final merger remnant is very similar for impact parameters of 0 and 5 core radii. It possesses a roughly isothermal core with central density and temperature twice the initial values for the colliding clusters. Outside the core, the temperature drops as r-1, and the density roughly as r-3.8. The core radius shows a small increase due to shock heating during the merger. For an impact parameter of 10 core radii, the core of the remnant possesses a more flattened density profile with a steeper drop-off outside the core. In both off-center cases, the merger remnant rotates, but only for the 10 core-radius case does this appear to have an effect on the structure of the remnant.
K-plet and coupled BFS: a graph based fingerprint representation and matching algorithm

In this paper, we present a new fingerprint matching algorithm based on graph matching principles. We define a new representation called K-plet to encode the local neighborhood of each minutiae. We also present CBFS (Coupled BFS), a new dual graph traversal algorithm for consolidating all the local neighborhood matches and analyze its computational complexity. The proposed algorithm is robust to non-linear distortion. Ambiguities in minutiae pairings are solved by employing a dynamic programming based optimization approach. We present an experimental evaluation of the proposed approach and showed that it exceeds the performance of the NIST BOZORTH3 [3] matching algorithm.
Dependence of the Outer Density Profiles of Halos on Their Mass Accretion Rate

We present a systematic study of the density profiles of ΛCDM halos, focusing on the outer regions, 0.1 1.7 × 1010 h –1 M ☉. We discuss observational signatures of the profile features described above and show that the steepening of the outer profile should be detectable in future weak-lensing analyses of massive clusters. Such observations could be used to estimate the mass accretion rate of cluster halos.
Substitutional chemistry in Mn5Si3-type scandium–main group compounds and the formation of quasibinary phases

Abstract The compositions Sc5M3−xM′x (M=Al or Ga; M′=Sn, Sb or Te) were prepared by high-temperature solid-state techniques, and their Mn5Si3-type structures were either identified by powder X-ray means or determined by single crystal X-ray diffraction (hexagonal P63/mcm (No. 193), Z=2). Each Al or Ga (M) atom type exhibits mixed occupancy with Sn, Sb, or Te (M′) over different composition regions. For systems annealed at 1100–1575°C, single crystal data indicate that the phase widths of Sc5M3−xM′x extend over the ranges x=1.38(6)–2.25(2), 0.83(1)–0.96(1), 0–2.25(6), and 0–1.25(3) for Al/Sb, Al/Te, Ga/Sb, and Ga/Te, respectively. Powder X-ray data on the Sn systems shows phase width ranges of x=∼1.2–3.0 with Al and 0.0–3.0 with Ga, respectively. No interstitials in the Mn5Si3-type host were seen. The series of mixed compounds illustrate regular effects of substitution of larger and electron-richer M′ atoms in the flexible structure. The lattice constant trends follow Vegard’s law, with natural increases of a (b) and V with increasing x, but with small and irregular changes in c. Physical property measurements show that many of the compounds display metallic characteristics, with positive temperature-dependent resistivity and Pauli-like paramagnetism. The structure of Sc5Sb3 is reassigned to the Y5Bi3-type (Pnma).
Constrained Substructure Approach to Optimal Strain Energy Analysis

The chief tool for design of viscoelastic-based damping treatments over the past 20 years has been the modal strain energy (MSE) approach. This approach to damping design traditionally has involved a practitioner to vary placement and stiffness of add-on elements using experience and trial and error so as to maximize the add-on element share of system MSE in modes of interest. In this paper we develop a new technique for maximizing strain energy as a function of stiffness for add-on structural elements modeled as rank r perturbations to the original stiffness matrix. The technique is based on a constrained substructure approach allowing us to parameterize strain energy in terms of the eigen-values of the perturbed structure. An optimality condition is derived that relates the input-output response at the attachment location of the add-on elements to the maximum achievable strain energy. A realizability condition is also derived which indicates whether or not the optimal solution is achievable with passive structural elements. This method has applications in the design of structural treatments for controlling sound and vibration and promises an efficient means of determining the limits of performance of passive structural treatments. An advantage of our approach over existing methods is that the maximum achievable strain energy fraction in the add-on elements is directly computable with the realizability condition then indicating whether the optimal solution is achievable.
Accidents will happen?: Unintentional childhood injuries and the effects of child care regulations

Accidents are the leading cause of death and injury among children in the United States, far surpassing diseases as a health threat. We examine the effects of child care regulation on rates of accidental injury using both micro data from the National Longitudinal Survey of Youth, and Vital Statistics mortality records. Estimates from both data sources suggest that requiring day care center directors to have more education reduces the incidence of unintentional injuries. An auxiliary analysis of the choice of child care mode confirms that these regulations are binding and that higher educational requirements tend to crowd some children out of care, as do regulations requiring frequent inspections of child care facilities and lower pupil-teacher ratios. Thus, regulation creates winners and losers: Some children benefit from safer environments, while those who are squeezed out of the regulated sector are placed at higher risk of injury.
Oxidation Processes and Phase Changes in Metastable Al-Mg Alloys

Oxidation behavior of metastable mechanical alloys in the Al-Mg binary system has been examined in the context of high-energy density materials and combustion applications. Mechanical alloy powders with compositions ranging from Al 0 . 9 5 Mg 0 . 0 5 to Al 0 . 5 Mg 0 . 5 , as well as the component metals, were heated at 20 K/min in oxygen. Differential thermal analysis and thermogravimetric analysis showed that oxidation proceeds in two separate steps. During the first step occurring over the range of 550-600°C, Mg is oxidized and thereby quantitatively removed from the metallic phase. The selective removal of Mg from the alloy was identified by correlation of weight gain with the Mg concentration of the alloy and by x-ray diffraction and scanning electron microscopy, of intermediate products. The second step, during which the remainder of the metallic phase is oxidized, occurs over a wider range of temperatures (900-1200°C). The temperatures of both effects decrease slightly with increasing Mg content in the alloy. Oxidation is increasingly incomplete as the Mg concentration of the alloy decreases below 30 at.%. It was concluded that the low-temperature selective oxidation of Mg is controlled by the volatilization of Mg from the alloy. No correlation could be established between the oxidation reactions and subsolidus phase transitions, which occur over the temperature range of 100-400°C and are associated with the relaxation of the metastable state of the mechanical alloys.
Automatically extracting sentences from Medline citations to support clinicians' information needs.

Objective Online health knowledge resources contain answers to most of the information needs raised by clinicians in the course of care. However, significant barriers limit the use of these resources for decision-making, especially clinicians' lack of time. In this study we assessed the feasibility of automatically generating knowledge summaries for a particular clinical topic composed of relevant sentences extracted from Medline citations. Methods The proposed approach combines information retrieval and semantic information extraction techniques to identify relevant sentences from Medline abstracts. We assessed this approach in two case studies on the treatment alternatives for depression and Alzheimer's disease. Results A total of 515 of 564 (91.3%) sentences retrieved in the two case studies were relevant to the topic of interest. About one-third of the relevant sentences described factual knowledge or a study conclusion that can be used for supporting information needs at the point of care. Conclusions The high rate of relevant sentences is desirable, given that clinicians' lack of time is one of the main barriers to using knowledge resources at the point of care. Sentence rank was not significantly associated with relevancy, possibly due to most sentences being highly relevant. Sentences located closer to the end of the abstract and sentences with treatment and comparative predications were likely to be conclusive sentences. Our proposed technical approach to helping clinicians meet their information needs is promising. The approach can be extended for other knowledge resources and information need types.
The waterpipe: a new way of hooking youth on tobacco.

Background Tobacco smoking continues to be the number one preventable cause of morbidity and mortality worldwide. Several evidence-based interventions and policies have been successful in reducing cigarette smoking in developed countries. Globally, however, many beginning smokers are introduced to tobacco by means other than cigarettes. In particular, waterpipe smoking (a.k.a. hookah, narghile, shisha) has been dramatically increasing among youth worldwide. Methods In this short review, I will introduce the reader to this emerging tobacco use method and focus on its addictive properties, and how this pertains to the development of effective interventions to curb its spread. Results and Conclusions Waterpipe smoking is likely to be associated with much of the harmful effects of cigarette smoking, is addictive, and can serve as a bridge to cigarettes. Due to its unique features, waterpipe-specific interventions and policies are needed to curb the global waterpipe epidemic. (Am J Addict 2014;23:103–107)
Generating and identifying optical orbital angular momentum with silicon photonic circuits

We demonstrate a fully integrated silicon photonic circuit capable of generating light carrying optical orbital angular momentum. Experimentally, orbital angular momentum wavefronts are identified by interfering with another on-chip generated Gaussian beam.
Damped Lyman alpha systems and galaxy formation models – II. High ions and Lyman-limit systems

We investigate a model for the high-ionization state gas associated with observed damped Lyman a systems, based on a semi-analytic model of galaxy formation set within the paradigm of hierarchical structure formation. In our model, the hot gas in haloes and subhaloes is assumed to be in a multiphase medium which gives rise to CIV absorption, while the low-ionization state gas is associated with the cold gas in galaxies. The model matches the distribution of C iv column densities if we assume that the hot gas has a mean metallicity log C/H = -1.5, which is the observed mean metallicity of damped systems. The same model then leads naturally to kinematic properties that are in good agreement with the data, for both the low- and high- ionization state gas. We examine the contribution of both hot and cold gas to subdamped systems (N H 1 > 4 × 10 1 9 cm - 2 ) and suggest that the properties of these systems can be used as an important test of the model. We expect that sub-DLA systems will generally be composed of a single gas disc and thus predict that they should have markedly different kinematics from the damped systems. We also find that the frequency of absorbers drops dramatically for column densities below 4 × 10 1 9 cm - 2 . These results are a consequence of our model for damped Lyman a systems and we believe they are a generic prediction of multicomponent models. Finally, we find that hot halo gas produces less than one-third of Lyman-limit systems at a redshift of 3. We model the contribution of mini-haloes (haloes with virial velocities ≤35 km s - 1 ) to Lyman-limit systems and find that they may contain as much gas as is observed in these systems. However, if we adopt realistic models of the gas density distribution we find that these systems are not a significant source of Lyman-limit absorption. Instead we suggest that uncollapsed gas outside of virialized haloes is responsible for most of the Lyman-limit systems at high redshift.
Diaza- and triazachrysenes: Potent topoisomerase-targeting agents with exceptional antitumor activity against the human tumor xenograft, MDA-MB-435

Several 5,12-diazachrysen-6-ones and 5,6,11-triazachrysen-12-ones were synthesized with varied substituents at the 5- or 11-position, respectively. Each compound was evaluated for its potential to stabilize the cleavable complex formed with TOP1 and DNA. Two analogues with very potent TOP1-targeting activity, 3a and 4a, exhibited cytotoxic activity with IC(50) values at or below 2nM against RPMI8402. Compound 3a was active in vivo by either ip or po administration in the human tumor xenograft athymic nude mice model.
Simple Synthesis of Substituted Pyrroles

Simple synthesis of substituted pyrroles using iodine-catalyzed and montmorillonite KSF-clay-induced modified Paal-Knorr methods has been accomplished with excellent yields. N-Substituted carbazole has also been prepared by following this method. If one of the reactants is a liquid, the reaction proceeds exceedingly well without a solvent. This method gives pyrroles with less nucleophilic multicyclic aromatic amines at room temperature.
Combined gravitational and thermocapillary interactions of spherical drops with incompressible surfactant

Collision efficiencies are calculated by a trajectory analysis for two contaminated spherical drops under the combined influence of buoyancy and a constant temperature gradient at low Reynolds number and with negligible thermal convection in the limit of nearly uniform surfactant coverage. As in the case of clean drops, a region in the parameter space exists where collisions are forbidden when the driving forces are opposed. However, because of the increased effect of thermocapillary repulsion when surfactant is present, coalescence can be inhibited even when the driving forces are aligned in the same direction. In addition to trajectories leading to coalescence and separation of the drops, closed trajectories are also observed. At parameter values where the asymmetric mobility function is zero, retrograde motion can occur, where the angle between vertical and the drops’ line of centers decreases as the drops come into contact. This retrograde motion requires alteration to the closed form expression for the collision efficiency. The effect of incompressible surfactant on dilute dispersions of two physical systems is also considered. Populations dynamics simulations for both driving forces aligned in the same direction with van der Waals attraction indicate that the volume-averaged radius begins to level out and then continues to grow because the collision efficiency passes through a minimum but is not identically zero.
Effect of putting grip on eye and head movements during the golf putting stroke.

The objective of this article is to determine the effect of three different putting grips (conventional, cross-hand, and one-handed) on variations in eye and head movements during the putting stroke. Seven volunteer novice players, ranging in age from 21 to 22 years, participated in the study. During each experimental session, the subject stood on a specially designed platform covered with artificial turf and putted golf balls towards a standard golf hole. The three different types of grips were tested at two distances: 3 and 9 ft. For each condition, 20 putts were attempted. For each putt, data were recorded over a 3-s interval at a sampling rate of 100 Hz. Eye movements were recorded using a helmet-mounted eye movement monitor. Head rotation about an imaginary axis through the top of the head and its center-of-rotation was measured by means of a potentiometer mounted on a fixed frame and coupled to the helmet. Putter-head motion was measured using a linear array of infrared phototransistors embedded in the platform. The standard deviation (STD, relative to the initial level) was calculated for eye and head movements over the duration of the putt (i.e., from the beginning of the backstroke, through the forward stroke, to impact). The averaged STD for the attempted putts was calculated for each subject. Then, the averaged STDs and other data for the seven subjects were statistically compared across the three grip conditions. The STD of eye movements were greater (p < 0.1) for conventional than cross-hand (9 ft) and one-handed (3 and 9 ft) grips. Also, the STD of head movements were greater (p < 0.1; 3 ft) for conventional than cross-hand and one-handed grips. Vestibulo-ocular responses associated with head rotations could be observed in many 9 ft and some 3 ft putts. The duration of the putt was significantly longer (p < 0.05; 3 and 9 ft) for the one-handed than conventional and cross-hand grips. Finally, performance, or percentage putts made, was significantly better (p < 0.05; 9 ft) for cross-hand than conventional grip. The smaller variations, both in eye movements during longer putts and head movements during shorter putts, using cross-hand and one-handed grips may explain why some golfers, based on their playing experience, prefer these over the conventional grip. Also, the longer duration for the one-handed grip, which improves tempo, may explain why some senior players prefer the long-shaft (effectively one-handed grip) putter.
On the capacity of channels with unknown interference

The process of communicating in the presence of interference that is unknown or hostile is modeled as a two-person zero-sum game with the communicator and the jammer as the players. The objective function considered is the rate of reliable communication. The communicator's strategies are encoders and distributions on a set of quantizers. The jammer's strategies are distributions on the noise power subject to certain constraints. Various conditions are considered on the jammer's strategy set and on the communicator's knowledge. For the case where the decoder is uninformed of the actual quantizer chosen, it is shown that, from the communicator's perspective, the worst-case jamming strategy is a distribution concentrated on a finite number of points, thereby converting a functional optimization problem into a nonlinear programming problem. Moreover, the worst-case distributions can be characterized by means of necessary and sufficient conditions which are easy to verify. For the case where the decoder is informed of the actual quantizer chosen, the existence of saddle-point strategies is demonstrated. The analysis is also seen to be valid for a number of situations where the jammer is adaptive. >
Rule-Based Interpretation of Aerial Imagery

In this paper, we describe the organization of a rule-based system, SPAM, that uses map and domain-specific knowledge to interpret airport scenes. This research investigates the use of a rule-based system for the control of image processing and interpretation of results with respect to a world model, as well as the representation of the world model within an image/map database. We present results on the interpretation of a high-resolution airport scene wvhere the image segmentation has been performed by a human, and by a region-based image segmentation program. The results of the system's analysis is characterized by the labeling of individual regions in the image and the collection of these regions into consistent interpretations of the major components of an airport model. These interpretations are ranked on the basis of their overall spatial and structural consistency. Some evaluations based on the results from three evolutionary versions of SPAM are presented.
Lactoferrin Protects Against Acetaminophen-Induced Liver Injury in Mice

Acetaminophen-induced liver injury (AILI) is a significant health problem and represents the most frequent cause of drug-induced liver failure in the United States. The development and implementation of successful therapeutic intervention strategies have been demanding, due to significant limitations associated with the current treatment for AILI. Lactoferrin (Lac), a glycoprotein present in milk, has been demonstrated to possess a multitude of biological functions. Our study demonstrated a profound protective effect of Lac in a murine model of AILI, which was not dependent on its iron binding ability, inhibition of acetaminophen (APAP) metabolism, or a direct cytoprotective effect on hepatocytes. Instead, Lac treatment significantly attenuated APAP-induced liver sinusoidal endothelial cell dysfunction and ameliorated hepatic microcirculation disorder. This protective effect of Lac appeared to be dependent on hepatic resident macrophages (Kupffer cells, KC). Collectively, our data indicated that Lac, through activation of KC, inhibited APAP-induced liver sinusoidal endothelial cell damage and improved hepatic congestion, thereby protecting against AILI. These findings reveal the significant therapeutic potential of Lac during AILI and other types of liver diseases.
SweetDeal: representing agent contracts with exceptions using XML rules, ontologies, and process descriptions

SweetDeal is a rule-based approach to representation of business contracts that enables software agents to create, evaluate, negotiate, and execute contracts with substantial automation and modularity. It builds upon the situated courteous logic programs knowledge representation in RuleML, the emerging standard for Semantic Web XML rules. Here, we newly extend the SweetDeal approach by also incorporating process knowledge descriptions whose ontologies are represented in DAML+OIL (emerging standard for Semantic Web ontologies) thereby enabling more complex contracts with behavioral provisions, especially for handling exception conditions (e.g., late delivery or non-payment) that might arise during the execution of the contract. This provides a foundation for representing and automating deals about services -- in particular, about Web Services, so as to help search, select, and compose them. Our system is also the first to combine emerging Semantic Web standards for knowledge representation of rules (RuleML) with ontologies (DAML+OIL) for a practical e-business application domain, and further to do so with process knowledge. This also newly fleshes out the evolving concept of Semantic Web Services. A prototype (soon public) is running.
When Do Fair Beliefs Influence Bargaining Behavior? Experimental Bargaining in Japan and the United States

In this research, we examine the influence of beliefs about fairness on bargaining behavior. Using a repeated ultimatum game, we examine bargaining contexts in Japan and the United States in which buyers' or sellers' fair beliefs are either in alignment with or in conflict with their own self-interest. We suggest that understanding the relationship between fair beliefs and self-interest is central to understanding when fair beliefs will influence bargaining behavior. Our results demonstrate that fair beliefs predict bargaining behavior when they are aligned with one's own self-interest.
G-optimal designs for multi-factor experiments with heteroscedastic errors

We consider constructing G-optimal designs for multi-factor experiments when the errors are heteroscedastic. The method is illustrated with examples assuming the Kronecker product models and the additive models. Sufficient conditions are given so that G-optimal designs for the multi-factor experiments can be constructed from the optimal designs for the single-factor experiments.
Optimal phase conflict removal for layout of dark field alternating phase shifting masks

We describe new, efficient algorithms for layout modification and phase assignment for dark field alternating-type phase shifting masks in the single exposure regime. We make the following contributions. First, we suggest new two-coloring and compaction approach that simultaneously optimizes layout and phase assignment which is based on planar embedding of an associated conflict graph. We also describe additional approaches to cooptimization of layout and phase assignment for alternating PSM. Second, we give optimal and fast algorithms to minimize the number of phase conflicts that must be removed to ensure two colorability of the conflict graph. We reduce this problem to the T-join problem which asks for a minimum weight edge set A such that a node u is incident to an odd number of edges of A if u belongs to a given node subset T of a weighted graph. Third, we suggest several practical algorithms for the T-join problem. In sparse graphs, our algorithms are faster than previously known methods. Computational experience with industrial VLSI layout benchmarks shows the advantages of the new algorithms.
Application of the aqueous porous pathway model to quantify the effect of sodium lauryl sulfate on ultrasound‐induced skin structural perturbation

This study investigated the effect of sodium lauryl sulfate (SLS) on skin structural perturbation when utilized simultaneously with low-frequency sonophoresis (LFS). Pig full-thickness skin (FTS) and pig split-thickness skin (STS) treated with LFS/SLS and LFS were analyzed in the context of the aqueous porous pathway model to quantify skin perturbation through changes in skin pore radius and porosity-to-tortuosity ratio (e/τ). In addition, skin treatment times required to attain specific levels of skin electrical resistivity were analyzed to draw conclusions about the effect of SLS on reproducibility and predictability of skin perturbation. We found that LFS/SLS-treated FTS, LFS/SLS-treated STS, and LFS-treated FTS exhibited similar skin perturbation. However, LFS-treated STS exhibited significantly higher skin perturbation, suggesting greater structural changes to the less robust STS induced by the purely physical enhancement mechanism of LFS. Evaluation of e/τ values revealed that LFS/SLS-treated FTS and STS have similar transport pathways, whereas LFS-treated FTS and STS have lower e/τ values. In addition, LFS/SLS treatment times were much shorter than LFS treatment times for both FTS and STS. Moreover, the simultaneous use of SLS and LFS not only results in synergistic enhancement, as reflected in the shorter skin treatment times, but also in more predictable and reproducible skin perturbation.