cssi/SciSciGPT-SciSciNet huggingface dataset:
Manticore: a heterogeneous parallel language

The Manticore project is an effort to design and implement a new functional language for parallel programming. Unlike many earlier parallel languages, Manticore is a heterogeneous language that supports parallelism at multiple levels. Specifically, we combine CML-style explicit concurrency with NESL/Nepal-style data-parallelism. In this paper, we describe and motivate the design of the Manticore language. We also describe a flexible runtime model that supports multiple scheduling disciplines (e.g., for both fine-grain and course-grain parallelism) in a uniform framework. Work on a prototype implementation is ongoing and we give a status report.
The scaling-up of microfinance in Bangladesh : determinants, impact, and lessons

The microfinance industry in Bangladesh currently provides access to credit to around 13 million poor households. The author describes the factors that led to the scaling-up of micro-credit in Bangladesh, the impact this has had on the poor, future challenges in Bangladesh, and possible lessons for other countries. The consensus in the literature is that micro-credit plays a significant role in reducing household vulnerability to a number of risks and that it contributes to improving social indicators. The author argues that strategic donor investments in a handful of well-managed institutions that offer a simple, easily replicable financial product could lead to large gains in access to finance for the poor. However, this approach could sacrifice other objectives of financial sector development, such as product and institutional diversity, which could be promoted after the initial expansion has taken place. Governments can also have a crucial role in promoting access to microfinance by ensuring macroeconomic stability, enforcing a simple regulatory structure, and developing communications networks that reduce transaction costs. Another lesson is that while visionary leadership cannot simply be franchised, the internal management systems that led to the scaling-up can be replicated in other settings.
A General Synthesis of N-Vinyl Nitrones

A general synthesis of a new type of heterodiene, the N-vinyl nitrone, is described. The synthetic sequence begins with the conjugate addition of benzeneselenol to nitroalkenes (in turn derived from Henry reaction of an aldehyde and a nitroalkane) to provide 2-selenenylnitroalkenes. These selenonitroalkanes are reduced to the corresponding hydroxylamines which are combined with aldehydes to form nitrones. The phenylselenenyl-containing nitrones are then oxidized to selenoxides which undergo syn-selenoxide elimination to provide N-vinyl nitrones. Three X-ray crystal structures of substituted N-vinyl nitrones were obtained. In addition, the first [4+2] cycloaddition of an N-vinyl nitrone is reported.
Finite-bandwidth calculations for charge carrier mobility in organic crystals

Finite-bandwidth effects on the temperature dependence of the mobility of injected carriers in pure organic crystals are explored for a simplifed case of impurity scattering. Temperature-dependent bandwidth effects are discussed briefly through a simplified combination of band and polaronic concepts.
Strength in Numbers: Probing and Understanding Intermolecular Bonding with Chemical Force Microscopy

Scanning probe microscopy (SPM) provided researchers with a simple, intuitive, and versatile tool for probing intermolecular interactions using SPM probes functionalized with distinct chemical species. Chemical force microscopy (CFM) was developed as a way to probe and map these interactions in a rational and systematic way. But does the rupture strength of a bond measured in these experiments provide the definitive and useful information about the interaction? The answer to this question is closely linked to understanding the fundamental physics of bond rupture under an external loading force. Even a simple model shows that bond rupture can proceed in a variety of different regimes. I discuss the approaches for extracting quantitative information about the interaction from these experiments and show that even though the measured rupture force is almost never unique for a given bond, force spectroscopy measurements can still determine the essential interaction parameters. SCANNING 30: 000–000, 2008. © 2008 Wiley Periodicals, Inc.
Information Efficiency of U.S. Restaurant Stocks that are Cross-Listed in Germany

We study relationships between stock returns on U.S. and German exchanges for U.S. restaurant companies. Specifically, we examine whether information asymmetry affect how much stock returns in Germany lag stock returns of the same company on U.S. markets. German and U.S. investors differ in information access because of differing stock exchange listing requirements. Our main goals are to examine if (a) stock returns of U.S. underlying shares lead stock returns of cross-listed shares on the Open Market because of information asymmetry and (b) the lead–lag relationship is more evident among shares involuntarily cross-listed on the Open Market than securities voluntarily cross-listed on the EU Regulated Market because of differences in regulation in information disclosure. We estimated cross-autocorrelations using vector autoregressions and tested the hypotheses with the Wald test. The results, in general, support both hypotheses.
RADIATIVE EQUILIBRIUM AND TEMPERATURE CORRECTION IN MONTE CARLO RADIATION TRANSFER

We describe a general radiative equilibrium and temperature correction procedure for use in Monte Carlo radiation transfer codes with sources of temperature-independent opacity, such as astrophysical dust. The technique utilizes the fact that Monte Carlo simulations track individual photon packets, so we may easily determine where their energy is absorbed. When a packet is absorbed, it heats a particular cell within the envelope, raising its temperature. To enforce radiative equilibrium, the absorbed packet is immediately reemitted. To correct the cell temperature, the frequency of the reemitted packet is chosen so that it corrects the temperature of the spectrum previously emitted by the cell. The reemitted packet then continues being scattered, absorbed, and reemitted until it finally escapes from the envelope. As the simulation runs, the envelope heats up, and the emergent spectral energy distribution (SED) relaxes to its equilibrium value without iteration. This implies that the equilibrium temperature calculation requires no more computation time than the SED calculation of an equivalent pure scattering model with fixed temperature. In addition to avoiding iteration, our method conserves energy exactly because all injected photon packets eventually escape. Furthermore, individual packets transport energy across the entire system because they are never destroyed. This long-range communication, coupled with the lack of iteration, implies that our method does not suffer the convergence problems commonly associated with Λ-iteration. To verify our temperature correction procedure, we compare our results with standard benchmark tests, and finally we present the results of simulations for two-dimensional axisymmetric density structures.
Ultrastructural investigation of crystal deposits in Npt2a knockout mice: are they similar to human Randall's plaques?

Purpose: Idiopathic Ca oxalate stones may develop with attachment to renal interstitial Ca phosphate deposits (Randall's plaques). Sodium phosphate cotransporter (Npt2a) null mice have hypercalciuria and hyperphosphaturia, and produce tubular and interstitial Ca phosphate deposits. To determine whether this mouse is suitable for Randall's plaque investigations we chronologically studied Ca phosphate deposit sites, structure and composition.Materials and Methods: The kidneys of Npt2a null mice 2 days to 1 year old were examined by light, scanning and transmission electron microscopy. Electron diffraction and energy dispersive x-ray microanalyses were done to determine mineral composition.Results: Poorly crystalline, biological apatite deposits were seen in collecting duct lumina. Deposits consisted of aggregates approximately 5 μm in diameter appearing as microspheres of concentrically organized needle or plate-like, matrix rich crystals. Epithelium/crystal interfaces were filled with membrane bound vesicl...
How Does the Global Economic Environment Influence the Demand for IMF Resources

The main objective of this paper is to quantify the relationship between the global economic environment and Stand-By Arrangements (SBAs) with the IMF. The results suggest that oil prices, world interest rates, and the global business cycle are the most influential indicators that affect the number of SBAs being requested. In addition, the empirical model seems to have reasonable accuracy when predicting SBAs. Furthermore, when oil prices, interest rates, and the global business cycle are adversely shocked by one standard deviation, the conditional probability of an SBA nearly doubles, implying an increase from about 6 to 12 SBAs. More critically, the model suggests that even a steady deterioration of the global economic climate would imply increasingly harsher conditions for developing and emerging market countries, which may in turn increase the demand for IMF resources significantly.
The History of Patenting Genetic Material

The US Supreme Court's recent decision in Association for Molecular Pathology v. Myriad Genetics, Inc. declared, for the first time, that isolated human genes cannot be patented. Many have wondered how genes were ever the subjects of patents. The answer lies in a nuanced understanding of both legal and scientific history. Since the early twentieth century, "products of nature" were not eligible to be patented unless they were "isolated and purified" from their surrounding environment. As molecular biology advanced, and the capability to isolate genes both physically and by sequence came to fruition, researchers (and patent offices) began to apply patent-law logic to genes themselves. These patents, along with other biological patents, generated substantial social and political criticism. Myriad Genetics, a company with patents on BRCA1 and BRCA2, two genes critical to assessing early-onset breast and ovarian cancer risk, and with a particularly controversial business approach, became the antagonist in an ultimately successful campaign to overturn gene patents in court. Despite Myriad's defeat, some questions concerning the rights to monopolize genetic information remain. The history leading to that defeat may be relevant to these future issues.
Two- and three-electrode impedance studies on 18650 Li-ion cells

Abstract Two- and three-electrode impedance measurements were made on 18650 Li-ion cells at different temperatures ranging from 35°C to −40°C. The ohmic resistance of the cell is nearly constant in the temperature range studied although the total cell impedance increases by an order of magnitude in the same temperature range. In contrast to what is commonly believed, we show from our three-electrode impedance results that, the increase in cell impedance comes mostly from the cathode and not from the anode. Further, the anode and cathode contribute to both the impedance loops (in the NyQuist plot).
Perspectives and new directions for the production of bioethanol using consolidated bioprocessing of lignocellulose

The U.S. DOE Energy Independence and Security Act (EISA) mandated attainment of a national production level of 36 billion gallons of biofuels (to be added to gasoline) by 2022, of which 21 billion gallons must be derived from renewable/sustainable feedstocks (e.g. lignocellulose). In order to attain these goals, the development of cost effective process technologies that can convert plant biomass to fermentable sugars must occur. An alternative route to production of bioethanol is the utilization of microorganisms that can both convert biomass to fermentable sugars and ferment the resultant sugars to ethanol in a process known as consolidated bioprocessing (CBP). Although various economic benefits and technology hurdles must be weighed in the course of choosing the CBP strategy to be pursued, we present arguments for developing the powerfully cellulolytic fungus, Trichoderma reesei, as an effective CBP microorganism.
Stereocontrolled photochemical [2 + 2] cycloaddition

Abstract Dimethyldicinnamyl- and diphenyldicinnamylsiloxane were synthesized from cinnamyl alcohol and dimethyl- and diphenyldichlorosilane, respectively. After photolysis, one cyclobutane product, the all trans isomer, was observed in nearly quantitative yield. Photolysis of cinnamyl alcohol under the same conditions results in very little cyclobutane formation.
The communicative function of ambiguity in language

We present a general information-theoretic argument that all efficient communication systems will be ambiguous, assuming that context is informative about meaning. We also argue that ambiguity allows for greater ease of processing by permitting efficient linguistic units to be re-used. We test predictions of this theory in English, German, and Dutch. Our results and theoretical analysis suggest that ambiguity is a functional property of language that allows for greater communicative efficiency. This provides theoretical and empirical arguments against recent suggestions that core features of linguistic systems are not designed for communication.
Thioalkylation of Meldrum 's Acid: Protected alkylidene derivatives of isopropylidene malonate

Thioalkylated Meldrum's acid is easily by treatment of Meldrum's acid with an aldehyde and thiophenol in the presence of catalytical amounts of piperidinium acetate (1–6, Table 1). The adducts 1–6 are crystalline, stable compounds and they can be caused to react directly with nucleophiles and dienes (see 37–12, Scheme 1). The regeneration of the parent olefin is effected thereby by simply dissolving the adduct under neutral or basic conditions. Extension of this method to thiocarboxylic acids allowed the preparation of the corresponding formaldehyde derivatives 13 and 15(Table 3).
The impact of crowding on time until abdominal CT interpretation in emergency department patients with acute abdominal pain.

AbstractObjective: We assessed the relationship between emergency department (ED) crowding and delays in care in patients presenting with abdominal pain who receive abdominal computed tomography (CT). Methods: Prospective cohort study of adults who presented over a 1-year period to 2 urban academic EDs with abdominal pain and received CT. Each subject had 3 validated crowding measures assigned at enrollment (ED census, waiting room number, number of admitted patients). These were normalized to quartiles to signify least to most crowded. The Cuzick test was used for trend and log-linear regression and tested the association between ED crowding and time from triage to CT read. The time interval was further decomposed into triage to room, room to CT order, and order to CT read times. The adjusted analysis controlled for age, sex, race, pain score, time of day, triage level, and site. Results:767 patients were enrolled (mean age, 44±17 years; 61% female; 60% black). Median time from triage to CT read was 375 ...
Templates for convex cone problems with applications to sparse signal recovery

This paper develops a general framework for solving a variety of convex cone problems that frequently arise in signal processing, machine learning, statistics, and other fields. The approach works as follows: first, determine a conic formulation of the problem; second, determine its dual; third, apply smoothing; and fourth, solve using an optimal first-order method. A merit of this approach is its flexibility: for example, all compressed sensing problems can be solved via this approach. These include models with objective functionals such as the total-variation norm, ||Wx||1 where W is arbitrary, or a combination thereof. In addition, the paper introduces a number of technical contributions such as a novel continuation scheme and a novel approach for controlling the step size, and applies results showing that the smooth and unsmoothed problems are sometimes formally equivalent. Combined with our framework, these lead to novel, stable and computationally efficient algorithms. For instance, our general implementation is competitive with state-of-the-art methods for solving intensively studied problems such as the LASSO. Further, numerical experiments show that one can solve the Dantzig selector problem, for which no efficient large-scale solvers exist, in a few hundred iterations. Finally, the paper is accompanied with a software release. This software is not a single, monolithic solver; rather, it is a suite of programs and routines designed to serve as building blocks for constructing complete algorithms.
Synthesis of Cyclic Ethers Utilizing a Cyclization–Fragmentation Strategy

Abstract A variety of cyclic ethers have been prepared via both solution phase and polymer-supported sequences of 3+2 cycloaddition of nitrile oxides to alkenes and dienes to give isoxazolines, followed by electrophile-induced cyclization. Library generation by alkylative elaboration of isoxazolines was unsuccessful, but both simple and substituted dienes were found suitable for polymer-supported formation of cyclic ethers of ring sizes five through seven.
Vaporization thermodynamics and enthalpy of formation of aluminum silicon carbide

The vaporization thermodynamics of aluminum silicon carbide was investigated using Knudsen effusion mass spectrometry. Vaporization occurred incongruently to give Al(g), SiC(s), and graphite as reaction products. The vapor pressure of aluminum above (Al4SiC4+ SiC + C) was measured using graphite effusion cells with orifice areas between 1.1 × 10−2and 3.9X10−4 cm2. The vapor pressure of aluminum obtained between 1427 and 1784 K using an effusion cell with the smallest orifice area, 3.9X10−4 cm2, is expressed as log p (Pa) =−(18567 ± 86) (K/T) + (12.143 ± 0.054) The third-law calculation of the enthalpy change for the reaction Al4SiC4(s) = 4Al(g) + SiC(hex) + 3C(s) using the present aluminum pressures gives ΔH°(298.15 K) = (1455 ± 79) kJ·mol−1. The corresponding second-law result is ΔH°(298.15 K) = (1456 ± 47) kJ·mol−1. The standard enthalpy of formation of Al4SiC4(s) from the elements calculated from the present vaporization enthalpy (third-law calculation) and the enthalpies of formation of Al(g) and hexagonal SiC is ΔH°f= -(221 ± 85) kJ·mol−1. The standard enthalpy of formation of Al4SiC4(s) from its constituent carbides Al4C3(s) and SiC(c, hex) is calculated to be ΔH°(298.15 K) = (38 ± 92) KJ·mol−1.
An adaptive spatial diversity receiver for non-Gaussian interference and noise

Standard linear diversity combining techniques are not effective in combating fading in the presence of non-Gaussian noise. An adaptive spatial diversity receiver is developed for wireless communication channels with slow, flat fading and additive non-Gaussian noise. The noise is modeled as a mixture of Gaussian distributions and the expectation-maximization (EM) algorithm is used to derive estimates for the model parameters. The transmitted signals are detected using a likelihood ratio test based on the parameter estimates. The new adaptive receiver converges rapidly, its bit error rate performance is very close to optimum when relatively short training sequences are used, and it appears to be relatively insensitive to mismatch between the noise model and the actual noise distribution. Simulation results are included that illustrate various aspects of the adaptive receiver performance.
Genital herpetic infection. Association with cervical dysplasia and carcinoma.

During a 5 1/2 year period 245 patients at Grady Memorial Hospital had cytologic evidence of an active genital herpetic infection. Cervical biopsies obtained in 98 of these patients showed a 23.7% incidence (58 cases) of cervical anaplasia including 4 cases of invasive and 12 cases of in situ squamous cell carcinoma. This is in contrast with the 1.6% overall incidence of cervical anaplasia among a control group of 245 apparently noninfected women of similar age and background and the 2.7% incidence found in the total 56418 women screened during this period. These findings suggest that either similar factors operate independently to produce both conditions or that the venereally transmitted (type 2) genital herpesvirus plays some etiologic role in precancerous and cancerous cervical lesions. Findings supporting 1 or the other theory are presented; however there is no firm conclusion which can be drawn. In either case the results reported here indicate that women with known genital herpetic infection should be followed closely as a special group with an increased risk of developing cervical anaplastic changes. (authors)
Phased array imaging of moving targets with randomized beam steering and area spotlighting

This paper presents a system model and inversion for imaging moving targets using phased arrays. The system model provides a mathematical framework to represent the motion of a moving target in the beam-steering domain which is identified as the slow-time domain. The inversion provides a reconstruction of the moving targets in the spatial and velocity domains. It is shown that a randomized beam steering strategy in the slow-time domain can improve the resolution in the velocity domain. The imaging problem is also formulated for a phased array system that spotlights a target area with its transmitted beam to improve the target to clutter power ratio, and obtains beam-steered data in the receive mode for high-resolution imaging. We cite a diagnostic medical ultrasound problem due to the practical difficulties and challenges that are associated with it.
Peak reduction and finite presentations for automorphism groups of right-angled Artin groups

We generalize the peak reduction algorithm (Whitehead’s theorem) for free groups to a theorem about a general right-angled Artin group AΓ. As an application, we find a finite presentation for the automorphism group AutAΓ that generalizes McCool’s presentation for the automorphism group of a finite rank free group. We also consider a stronger generalization of peak reduction, giving a counterexample and proving a special case.
PEGylated polymers for medicine: from conjugation to self-assembled systems

Synthetic polymers have transformed society in many areas of science and technology, including recent breakthroughs in medicine. Synthetic polymers now offer unique and versatile platforms for drug delivery, as they can be “bio-tailored” for applications as implants, medical devices, and injectable polymer-drug conjugates. However, while several currently used therapeutic proteins and small molecule drugs have benefited from synthetic polymers, the full potential of polymer-based drug delivery platforms has not yet been realized. This review examines both general advantages and specific cases of synthetic polymers in drug delivery, focusing on PEGylation in the context of polymer architecture, self-assembly, and conjugation techniques that show considerable effectiveness and/or potential in therapeutics.
Effect of four computer keyboards in computer users with upper extremity musculoskeletal disorders

Eighty computer users with musculoskeletal disorders participated in a 6-month, randomized, placebo-controlled trial evaluating the effects of four computer keyboards on clinical findings, pain severity, functional hand status, and comfort. The alternative geometry keyboards tested were: the Apple Adjustable Keyboard [kb1], Comfort Keyboard System [kb2], Microsoft Natural Keyboard [kb3], and placebo. Compared to placebo, kb3 and to a lesser extent kb1 groups demonstrated an improving trend in pain severity and hand function following 6 months of keyboard use. However, there was no corresponding consistent improvement in clinical findings in the alternative geometry keyboard groups compared to the placebo group. Overall, there was a significant correlation between improvement of pain severity and greater satisfaction with the keyboards. These results provide evidence that keyboard users may experience a reduction in hand pain after several months of use of some alternative geometry keyboards.
The Entropy Per Coordinate of a Random Vector is Highly Constrained Under Convexity Conditions

The entropy per coordinate in a log-concave random vector of any dimension with given density at the mode is shown to have a range of just 1. Uniform distributions on convex bodies are at the lower end of this range, the distribution with i.i.d. exponentially distributed coordinates is at the upper end, and the normal is exactly in the middle. Thus, in terms of the amount of randomness as measured by entropy per coordinate, any log-concave random vector of any dimension contains randomness that differs from that in the normal random variable with the same maximal density value by at most 1/2. As applications, we obtain an information-theoretic formulation of the famous hyperplane conjecture in convex geometry, entropy bounds for certain infinitely divisible distributions, and quantitative estimates for the behavior of the density at the mode on convolution. More generally, one may consider so-called convex or hyperbolic probability measures on Euclidean spaces; we give new constraints on entropy per coordinate for this class of measures, which generalize our results under the log-concavity assumption, expose the extremal role of multivariate Pareto-type distributions, and give some applications.
Dynamic camera calibration of roadside traffic management cameras for vehicle speed estimation

In this paper, we present a new three-stage algorithm to calibrate roadside traffic management cameras and track vehicles to create a traffic speed sensor. The algorithm first estimates the camera position relative to the roadway using the motion and edges of the vehicles. Given the camera position, the algorithm then calibrates the camera by estimating the lane boundaries and the vanishing point of the lines along the roadway. The algorithm transforms the image coordinates from the vehicle tracker into real-world coordinates using our simplified camera model. We present results that demonstrate the ability of our algorithm to produce good estimates of the mean vehicle speed in a lane of traffic.
A dynamic programming algorithm for RNA structure prediction including pseudoknots

We describe a dynamic programming algorithm for predicting optimal RNA secondary structure, including pseudoknots. The algorithm has a worst case complexity of O(N6) in time and O(N4) in storage. The description of the algorithm is complex, which led us to adopt a useful graphical representation (Feynman diagrams) borrowed from quantum field theory. We present an implementation of the algorithm that generates the optimal minimum energy structure for a single RNA sequence, using standard RNA folding thermodynamic parameters augmented by a few parameters describing the thermodynamic stability of pseudoknots. We demonstrate the properties of the algorithm by using it to predict structures for several small pseudoknotted and non-pseudoknotted RNAs. Although the time and memory demands of the algorithm are steep, we believe this is the first algorithm to be able to fold optimal (minimum energy) pseudoknotted RNAs with the accepted RNA thermodynamic model.
THE WEIL-PETERSSON GEOMETRY ON THE THICK PART OF THE MODULI SPACE OF RIEMANN SURFACES

In the thick part of the moduli space of Riemann surface, we show the sectional curvature of the Weil-Petersson metric is bounded independent of the genus of the surface.
Immunosuppressive Effects and Safety of a Sirolimus/Cyclosporine Combination Regimen for Renal Transplantation

Background. Sirolimus, a novel immunosuppressant that inhibits cytokine-driven cell proliferation and maturation, prolongs allograft survival in animal models. After a phase I trial in stable renal transplant recipients documented that cyclosporine and sirolimus have few overlapping toxicities, we conducted an open-label, single-center, phase I/II dose-escalation trial to examine the safety and efficacy of this drug combination. Methods. Forty mismatched living-donor renal transplant recipients were sequentially assigned to receive escalating initial doses of sirolimus (0.5-7.0 mg/m 2 /day), in addition to courses of prednisone and a concentration-controlled regimen of cyclosporine. We conducted surveillance for drug-induced side effects among sirolimus-treated patients and compared their incidence of acute rejection episodes as well as mean laboratory values with those of a historical cohort of 65 consecutive, immediately precedent, demographically similar recipients treated with the same concentration-controlled regimen of cyclosporine and tapering doses of prednisone. Results. The addition of sirolimus reduced the overall incidence of acute allograft rejection episodes to 7.5% from 32% in the immediately precedent cyclosporine/prednisone-treated patients. At 18- to 47-month follow-up periods, both treatment groups displayed similar rates of patient and graft survival, as well as morbid complications. Although sirolimus-treated patients displayed comparatively lower platelet and white blood cell counts and higher levels of serum cholesterol and triglycerides, sirolimus did not augment the nephrotoxic or hypertensive proclivities of cyclosporine. The degree of change in the laboratory values was more directly associated with whole blood trough drug concentrations than with doses of sirolimus. Conclusions. Sirolimus potentiates the immunosuppressive effects of a cyclosporine-based regimen by reducing the rate of acute rejection episodes.
Thermal Conductance of an Individual Single-Wall Carbon Nanotube above Room Temperature

The thermal properties of a suspended metallic single-wall carbon nanotube (SWNT) are extracted from its high-bias (I−V) electrical characteristics over the 300−800 K temperature range, achieved by Joule self-heating. The thermal conductance is approximately 2.4 nW/K, and the thermal conductivity is nearly 3500 Wm-1K-1 at room temperature for a SWNT of length 2.6 μm and diameter 1.7 nm. A subtle decrease in thermal conductivity steeper than 1/T is observed at the upper end of the temperature range, which is attributed to second-order three-phonon scattering between two acoustic modes and one optical mode. We discuss sources of uncertainty and propose a simple analytical model for the SWNT thermal conductivity including length and temperature dependence.
Assessing the contributions of surface waves and complex rays to far-field Mie scattering by use of the Debye series

The contributions of complex rays and the secondary radiation shed by surface waves to scattering by a dielectric sphere are calculated in the context of the Debye series expansion of the Mie scattering amplitudes. Also, the contributions of geometrical rays are reviewed and compared with the Debye series. Interference effects between surface waves, complex waves, and geometrical waves are calculated, and the possibility of observing these interference effects is discussed. Experimental data supporting the observation of a surface wave-geometrical pattern is presented.
Displacement field of the cytoskeleton in response to a local load

Mechanical stresses acting on the apical cell surface are transmitted to the anchoring sites of the cell via cytoskeletal polymers, but details of the stress-, strain- or deformation field within the cell are largely unknown. Here we have measured the deformation field within cultured smooth muscle cells in response to small stresses. Stresses were applied to integrin receptors on the cell surface via magnetic microbeads (4.5 /spl mu/m diameter). The beads were torqued in a sinusoidally varying magnetic twisting field (specific torque amplitude of 90 Pa, frequency 0.3 Hz). Cells were transfected to express either fluorescent mitochondria, microfilaments, or microtubules. Ten images were taken during each of ten or more twisting cycles, from which we computed the deformation field within the cell. Our results confirm that mechanical stresses in cells can be transmitted via focal adhesions on the apical cell surface to the internal cytoskeleton. Importantly, cytoskeletal deformations in most cells decayed to below the resolution limit within a short distance (/spl sim/5/spl mu/m) from the locus of stress application.
Pontryagin's principle of stabilization

The paper presents necessary and sufficient conditions for a nonlinear system to be stabilized by a feedback. The conditions are based on the ideas related to the well-known Pontryagin's maximum principle. That allows us to formulate the results in terms that are valid for continuous, discontinuous, stationary and time-dependent feedbacks.
The Distinct Influence of Cognitive Busyness and Need for Closure on Cultural Differences in Socially Desirable Responding

Research suggests that cognitive busyness and need for closure have similar effects on a host of consumer phenomena, leading some researchers to treat the two variables as substitutes. We propose that cognitive busyness and need for closure have distinct roots and can have different effects. We examine their distinction in the context of cultural differences in the two types of socially desirable responding—impression management and self‐deceptive enhancement. Our findings indicate that high (vs. low) cognitive busyness weakens the relationship between culture and impression management, but not that between culture and self‐deceptive enhancement. In contrast, high (vs. low) need for closure strengthens both relationships. The article concludes with a discussion of the theoretical, methodological, and practical implications of these findings.
An Iterative Locally Linear Embedding Algorithm

Locally Linear embedding (LLE) is a popular dimension reduction method. In this paper, we systematically improve the two main steps of LLE: (A) learning the graph weights W, and (B) learning the embedding Y. We propose a sparse nonnegative W learning algorithm. We propose a weighted formulation for learning Y and show the results are identical to normalized cuts spectral clustering. We further propose to iterate the two steps in LLE repeatedly to improve the results. Extensive experiment results show that iterative LLE algorithm significantly improves both classification and clustering results.
Clustering via Dirichlet Process Mixture Models for Portable Skill Discovery

Skill discovery algorithms in reinforcement learning typically identify single states or regions in state space that correspond to task-specific subgoals. However, such methods do not directly address the question of how many distinct skills are appropriate for solving the tasks that the agent faces. This can be highly inefficient when many identified subgoals correspond to the same underlying skill, but are all used individually as skill goals. Furthermore, skills created in this manner are often only transferable to tasks that share identical state spaces, since corresponding subgoals across tasks are not merged into a single skill goal. We show that these problems can be overcome by clustering subgoal data defined in an agent-space and using the resulting clusters as templates for skill termination conditions. Clustering via a Dirichlet process mixture model is used to discover a minimal, sufficient collection of portable skills.
Charge fluctuations in YBa2Cu3O6+x superconductors

Abstract Striped phases in which spin and charge separate into different regions in the material have been proposed to account for the unusual properties of the high-Tc cuprate superconductors. The driving force for a striped phase is the charge distribution, which self-organizes itself into linear regions. In the highest Tc materials such regions are not static but fluctuate in time. Neutrons, having no charge, cannot directly observe these fluctuations but they can be observed indirectly by their effect on the phonons. Neutron scattering measurements have been made using a specialized technique to study the phonon line shapes in four crystals with oxygen doping levels varying from highly underdoped to optimal doping. It is shown that fluctuating charge stripes exist over the whole doping range, and become visible below temperatures somewhat higher than the pseudogap temperature.
A simple Cooperative diversity method based on network path selection

Cooperative diversity has been recently proposed as a way to form virtual antenna arrays that provide dramatic gains in slow fading wireless environments. However, most of the proposed solutions require distributed space-time coding algorithms, the careful design of which is left for future investigation if there is more than one cooperative relay. We propose a novel scheme that alleviates these problems and provides diversity gains on the order of the number of relays in the network. Our scheme first selects the best relay from a set of M available relays and then uses this "best" relay for cooperation between the source and the destination. We develop and analyze a distributed method to select the best relay that requires no topology information and is based on local measurements of the instantaneous channel conditions. This method also requires no explicit communication among the relays. The success (or failure) to select the best available path depends on the statistics of the wireless channel, and a methodology to evaluate performance for any kind of wireless channel statistics, is provided. Information theoretic analysis of outage probability shows that our scheme achieves the same diversity-multiplexing tradeoff as achieved by more complex protocols, where coordination and distributed space-time coding for M relay nodes is required, such as those proposed by Laneman and Wornell (2003). The simplicity of the technique allows for immediate implementation in existing radio hardware and its adoption could provide for improved flexibility, reliability, and efficiency in future 4G wireless systems.
The Block Relation in Computable Linear Orders

The block relation B(x, y) in a linear order is satisfied by elements that are finitely far apart; a block is an equivalence class under this relation. We show that every computable linear order with dense condensation-type (i.e., a dense collection of blocks) but no infinite, strongly η-like interval (i.e., with all blocks of size less than some fixed, finite k) has a computable copy with the non-block relation ¬B(x, y) computably enumerable. This implies that every computable linear order has a computable copy with a computable non-trivial self-embedding, and that the long-standing conjecture characterizing those computable linear orders every computable copy of which has a computable non-trivial self-embedding (as precisely those that contain an infinite, strongly η-like interval) holds for all linear orders with dense condensation-type.
On one approach to the control of uncertain systems

This paper is a personal history of one area of research with which I have been concerned over the past twenty years and which continues to attract my albeit waning attention, the control of dynamical systems based on uncertain models. Thus it is a subjective account of various factors which I believe to have steered me to approach the problem via a constructive use of Lyapunov stability theory. >
Gas-rich Mergers in LCDM: Disk Survivability and the Baryonic Assembly of Galaxies

We use N-body simulations and observationally normalized relations between dark matter halo mass, stellar mass, and cold gas mass to derive robust expectations about the baryonic content of major mergers out to redshift z ~ 2. First, we find that the majority of major mergers (m/M>0.3) experienced by the Milky Way size dark matter halos should have been gas-rich, and that gas-rich mergers are increasingly common at high redshifts. Though the frequency of major mergers into galaxy halos in our simulations greatly exceeds the observed early-type galaxy fraction, the frequency of gas-poor major mergers is consistent with the observed fraction of bulge-dominated galaxies across the halo mass range M DM ~ 1011-1013 M ☉. These results lend support to the conjecture that mergers with high-baryonic gas fractions play an important role in building and/or preserving disk galaxies in the universe. Second, we find that there is a transition mass below which a galaxy's past major mergers were primarily gas-rich and above which they were gas-poor. The associated stellar mass scale corresponds closely to that marking the observed bimodal division between blue, star-forming, disk-dominated systems and red, bulge-dominated systems with old populations. Finally, we find that the overall fraction of a galaxy's cold baryons deposited directly via major mergers is significant. Approximately ~20%-30% of the cold baryonic material in M star ~ 1010.5 M ☉ (M DM ~ 1012 M ☉) galaxies is accreted as cold gas or stars via major mergers since z = 2, with most of this accretion in the form of cold gas. For more massive galaxies with M star ~ 1011 M ☉ (M DM ~ 1013 M ☉), the fraction of baryons amassed in mergers since z = 2 is even higher, ~40%, but most of these accreted baryons are delivered directly in the form of stars. This baryonic mass deposition is almost unavoidable, and provides a limit on the fraction of a galaxy's cold baryons that can originate in cold flows or from hot halo cooling.
Evolution of Gravitationally Unstable de Sitter Compactifications

We study the time evolution of unstable dSp × S q configurations with flux in theories of gravity with a cosmological constant. For certain values of the flux, we identify a stable configuration to which these unstable solutions flow. For other values of the flux the sphere wants to decompactify, regardless of the sign of the initial perturbation.
Dynamic Process Improvement

This paper explores the economics of investing in gradual process improvement, a key component, with empirically supported importance, of the well known Just-in-Time and Total Quality Control philosophies. We formulate a Markov decision process, analyze it, and apply it to the problem of setup reduction and process quality improvement. Instead of a one-time investment opportunity for a large predictable technological advance, we allow many smaller investments over time, with potential process improvements of random magnitude. We use a somewhat nonstandard formulation of the immediate return, which facilitates the derivation of results. The policy that simply maximizes the immediate return, called the last chance policy, provides an upper bound on the optimal investment amount. Furthermore, if the last chance policy invests in process improvement, then so does the optimal policy. Each continues investing until a shared target state is attained. We derive fairly restrictive conditions that must be met for the policy of investing forever in process improvements to be optimal. Decreasing the uncertainty of the process making the potential improvements more predictable has a desirable effect: the total return is increased and the target state increases, so the ultimate system is more productive. Numerical examples are presented and analyzed.
A total synthesis of (±)-anhydrocannabisativine.

Abstract Recemic anhydrocannabisativine has been efficiently synthesized starting with a β lactoXXXamino other coupling reaction. A key step in the formation of the tetrahydropyridine molety of anhydrocannabisativine is a stereoselective intramolecular conjugate addition of the N-11 amino group to a Z . E -dienone.
Studying Ordinary Events in a Field Devoted to the Extraordinary.

Although a general understanding of the phenomenon of giftedness is evident in the literature, missing is a body of information on the thoughts and actions of gifted persons in those situations that we suspect influence the emergence of extraordinary accomplishment. In this article I propose a change in direction for the study of the advanced development. Grounded in the theoretically based research of Feldman and Vygotsky, I argue that we focus on the ordinary parts of life that contribute to extraordinary achievements. People should be studied within a field over a period of time. We have tended to look at characteristics of persons and products and, less so, on the process that yielded extraordinary accomplishment. Whatever methodologies we use, they must allow us to look at the individual and at the situation in detail. Suggestions for conducting such studies are offered. Extraordinary accomplishment is something that fascinates most people. How is it that peoples do such things? Much has been written in the popular press, there has been much coverage on television coverage, and many biographies have been written about people who accomplish extraordinary feats. Some behaviors are interesting, bizarre, and mere curiosities, as might be reported in Ripley’s Believe It or Not; others are indicative of accomplishments that advance our knowledge and understanding of the world and the human condition (see Gardner, 1983; Geortzel, Geortzel, & Geortzel, 1962.) In this article I am concerned with examples that fit the latter category and how these kinds of human accomplishments come to be. Extraordinary accomplishment is a recurrent theme in human history. The extraordinary achievements that mark human activity serve as signs of the ability of humans to invent new ways of being in the world. The field of gifted-person education is concerned with understanding and promoting the emergence of such innovative actions and thoughts.
Constraints on the Production of Ultra–High-Energy Cosmic Rays by Isolated Neutron Stars

The energetics, spectrum, and composition of cosmic rays with energies below D1015 eV are fairly well explained by models involving supernova shocks. In contrast, no widely accepted theory exists for the origin of ultraEhigh-energy cosmic rays (UHECRs), which have energies above 1015 eV. Instead of proposing a speci-c model, here we place strong constraints on any model of UHECRs involving iso- lated neutron stars (no companions). We consider the total power requirements and show that the only viable power source associated with isolated neutron stars is rotation. Mechanisms based on accretion from the interstellar medium fall short of the necessary power despite the most optimistic assumptions. Power considerations also demonstrate that not enough rotational energy is tapped by a "" propeller II- like acceleration of interstellar matter. The most promising source of energy is rotational spindown via magnetic braking. We examine microphysical energy loss processes near magnetized neutron stars and conclude that the most likely site for yielding UHECRs from isolated neutron stars is near or beyond the light cylinder. Subject headings: acceleration of particles E cosmic rays E stars: neutron
Birational Geometry of the Space of Complete Quadrics

Let $X$ be the moduli space of complete $(n-1)$-quadrics. In this thesis, we study the birational geometry of $X$ using tools from the minimal model program (MMP). In Chapter $1$, we recall the definition of the space $X$ and summarize our main results in Theorems A, B and C. \medskip In Chapter $2$, we examine the codimension-one cycles of the space $X$, and exhibit generators for Eff$(X)$ and Nef$(X)$ (Theorem A), the cone of effective divisors and the cone of nef divisors, respectively. This result, in particular, allows us to conclude the space $X$ is a Mori dream space. \medskip In Chapter $3$, we study the following question: when does a model of $X$, defined as $X(D):= \mathrm{Proj}(\bigoplus_{m\ge 0}H^0(X,mD))$, have a moduli interpretation? We describe such an interpretation for the models $X(H_k)$ (Theorem B), where $H_k$ is any generator of the nef cone $\mathrm{Nef}(X)$. In the case of complete quadric surfaces there are 11 birational models $X(D)$ (Theorem B), where $D$ is a divisor in the movable cone $\mathrm{Mov}(X)$, and among which we find a moduli interpretation for seven of them. \medskip Chapter 4 outlines the relation of this work with that of Semple \cite{SEM}, \cite{SEMII} as well as future directions of research.