cssi/SciSciGPT-SciSciNet huggingface dataset:
Integrated Reasoning and Proof Choice Point Selection in the Jahob System --- Mechanisms for Program Survival

In recent years researchers have developed a wide range of powerful automated reasoning systems. We have leveraged these systems to build Jahob, a program specification, analysis, and verification system. In contrast to many such systems, which use a monolithic reasoning approach, Jahob provides a general integrated reasoning framework, which enables multiple automated reasoning systems to work together to prove the desired program correctness properties. We have used Jahob to prove the full functional correctness of a collection of linked data structure implementations. The automated reasoning systems are able to automatically perform the vast majority of the reasoning steps required for this verification. But there are some complex verification conditions that they fail to prove. We have therefore developed a proof language, integrated into the underlying imperative Java programming language, that developers can use to control key choice points in the proof search space. Once the developer has resolved these choice points, the automated reasoning systems are able to complete the verification. This approach appropriately leverages both the developer's insight into the high-level structure of the proof and the ability of the automated reasoning systems to perform the mechanical steps required to prove the verification conditions. Building on Jahob's success with this challenging program verification problem, we contemplate the possibility of verifying the complete absence of fatal errors in large software systems. We envision combining simple techniques that analyze the vast majority of the program with heavyweight techniques that analyze those more sophisticated parts of the program that may require arbitrarily sophisticated reasoning. Modularity mechanisms such as abstract data types enable the sound division of the program for this purpose. The goal is not a completely correct program, but a program that can survive any remaining errors to continue to provide acceptable service.
Near-Infrared Photometric Variability of Stars toward the Orion A Molecular Cloud

We present an analysis of J, H, and K_s time-series photometry obtained with the southern 2MASS telescope over a 0.°84 × 6° region centered near the Trapezium region of the Orion Nebula cluster. These data are used to establish the near-infrared variability properties of pre–main-sequence stars in Orion on timescales of ~1–36 days, ~2 months, and ~2 years. A total of 1235 near-infrared variable stars are identified, ~93% of which are likely associated with the Orion A molecular cloud. The variable stars exhibit a diversity of photometric behavior with time, including cyclic fluctuations with periods up to 15 days, aperiodic day-to-day fluctuations, eclipses, slow drifts in brightness over 1 month or longer, colorless variability (within the noise limits of the data), stars that become redder as they fade, and stars that become bluer as they fade. The mean peak-to-peak amplitudes of the photometric fluctuations are ~0.2 mag in each band, and 77% of the variable stars have color variations less than 0.05 mag. The more extreme stars in our sample have amplitudes as large as ~2 mag and change in color by as much as ~1 mag. The typical timescale of the photometric fluctuations is less than a few days, indicating that near-infrared variability results primarily from short-term processes. We examine rotational modulation of cool and hot starspots, variable obscuration from an inner circumstellar disk, and changes in the mass accretion rate and other physical properties in a circumstellar disk as possible physical origins of the near-infrared variability. Cool spots alone can explain the observed variability characteristics in ~56%–77% of the stars, while the properties of the photometric fluctuations are more consistent with hot spots or extinction changes in at least 23% of the stars, and with variations in the disk mass accretion rate or inner disk radius in ~1% of our sample. However, differences between the details of the observations and the details of variability predicted by hot-spot, extinction, and accretion disk models suggest either that another variability mechanism not considered here may be operative or that the observed variability represents the net results of several of these phenomena. Analysis of the star-count data indicates that the Orion Nebula cluster is part of a larger area of enhanced stellar surface density that extends over a 0.°4 × 2.°4 (3.4 pc × 20 pc) region containing ~2700 stars brighter than Ks = 14 mag.
A study of fermions coupled to gauge and gravitational fields on a cylinder

Abstract Fermions on a cylinder coupled to background gravitation and gauge fields are examined by studying the geometric action associated with the symmetries of such a system. We are able to show that the gauge coupling constant is constrained to a value of 1/ N where N is an integer. Furthermore, in direct analogy with a Yang-Mills theory a new gravitational theory is introduced which couples to the fermions by promoting the coadjoint vector of the diffeomorphism sector to a dynamical variable. The classical dynamics of this theory are examined by displaying its symplectic structure and showing that it is equivalent to a one-dimensional system.
Atomic and Molecular Gas in Colliding Galaxy Systems. I. The Data

We present H I and CO (1-0) interferometric observations of 10 comparable-mass interacting systems obtained at the Very Large Array (VLA) and the Owens Valley Radio Observatory (OVRO) millimeter array. The primary intent of this study is to investigate the response of cold gas during the early stages of collision of massive disk galaxies. The sample sources are selected based on their luminosity (MB ≤ -19), projected separation (5-40 kpc), and single-dish CO (1-0) content (SCO ≥ 20 Jy km s-1). These selection criteria result in a sample that primarily consists of systems in the early stages of an interaction or a merger. Despite this sample selection, 50% of the systems show long H I tidal tails indicative of a tidal disruption in a prograde orbit. In addition, all (4/4) of the infrared luminous pairs (LIRGs) in the sample show long H I tails, suggesting that the presence of a long H I tail can be a possible signature of enhanced star formation activity in a collision of gas-rich galaxies. More than half of the groups show a displacement of H I peaks from the stellar disks. The CO (1-0) distribution is generally clumpy and widely distributed, unlike in most IR-selected late stage mergers—in fact, CO peaks are displaced from the stellar nucleus in 20% (4/18) of the galaxies with robust CO detection. H I and CO (1-0) position-velocity diagrams (PVDs) and rotation curves are also presented, and their comparison with the numerical simulation analyzed in Paper I show evidence for radial inflow and wide occurrences of nuclear molecular rings. These results are further quantified by examining physical and structural parameters derived in comparison with isolated systems in the BIMA SONG sample in our forthcoming paper.
Property-Value Impacts of an Environmental Disamenity: The Case of Landfills

The purpose of this article is to quantify the property-value impacts of a change in environmental quality by using the hedonic price model. In particular, we focus on the impact of the presence of landfills on nearby residential real estate prices. We combine elements of an urban location choice and hedonic pricing model to estimate the effects of the presence of multiple environmental disamenities on residential real estate prices. We explicitly account for temporal effects by including housing transactions in areas with both open and closed landfills and control for information effects. In addition, we treat property taxes and prices as being simultaneously determined. Our analysis suggests that closing landfills will not necessarily mitigate property-value impacts.
Fault oblivious high performance computing with dynamic task replication and substitution

Traditional parallel programming techniques will suffer rapid deterioration of performance scaling with growing platform size, as the work of coping with increasingly frequent failures dominates over useful computation. To address this challenge, we introduce and simulate a novel software architecture that combines a task dependency graph with a substitution graph. The role of the dependency graph is to limit communication and checkpointing and enhance fault tolerance by allowing graph neighbors to exchange data, while the substitution graph promotes fault oblivious computing by allowing a failed task to be substituted on-the-fly by another task, incurring a quantifiable error. We present optimization formulations for trading off substitution errors and other factors such as available system capacity and low-overlap task partitioning among processors, and demonstrate that these can be approximately solved in real time after some simplifications. Simulation studies of our proposed approach indicate that a substitution network adds considerable resilience and simple enhancements can limit the aggregate substitution errors.
Congenital subglottic stenosis.

2. Townes, P. L.: Trypsinogen deficiency and other proteolytic deficiency diseases, Fourth Conference Clinical Delineation of Birth Defects: Original Article Series 8" 95, 1972. 3. Holt, L. E., and McIntosh, E., editors: Holt's diseases of infancy and childhood, ed. 11, New York, 1940, Appleton-Century-Crofts, Inc., p. 150. 4. Shwachman, H.: Diagnosis of fibrocystie disease of the pancreas and partial pancreatic insufficiency, Proc. Eighteenth Ross Pediatrics Research Conference, 1956, pp. 53-58. 5. McDougall, C.: Clinical evaluation of abnormal enzyme content of the pancreatic juice of children, Pediatrics 5: 114, 1950. 6. Hadorn, B., Zoppi, G., Shmerling, D. H., Prader, A., McIntyre, I., and Anderson, C. M.: Quantitative assessment of exocrine pancreatic function in infants and children, J. P~DIATR. 73: 39, 1968. 7. Lowe, C. U., and May, C. D.: Selective pancreatic deficiency: Absent amylase, diminished trypsin, and normal lipase, Am. J. Dis. Child. 82: 459, 1951.
On Learning With Finite Memory

We consider an infinite collection of agents who make decisions, sequentially, about an unknown underlying binary state of the world. Each agent, prior to making a decision, receives an independent private signal whose distribution depends on the state of the world. Moreover, each agent also observes the decisions of its last K immediate predecessors. We study conditions under which the agent decisions converge to the correct value of the underlying state. We focus on the case where the private signals have bounded information content and investigate whether learning is possible, that is, whether there exist decision rules for the different agents that result in the convergence of their sequence of individual decisions to the correct state of the world. We first consider learning in the almost sure sense and show that it is impossible, for any value of K. We then explore the possibility of convergence in probability of the decisions to the correct state. Here, a distinction arises: if K=1, learning in probability is impossible under any decision rule, while for K ≥ 2, we design a decision rule that achieves it. We finally consider a new model, involving forward looking strategic agents, each of which maximizes the discounted sum (over all agents) of the probabilities of a correct decision. (The case, studied in the previous literature, of myopic agents who maximize the probability of their own decision being correct is an extreme special case.) We show that for any value of K, for any equilibrium of the associated Bayesian game, and under the assumption that each private signal has bounded information content, learning in probability fails to obtain.
Charm production and parton distributions

Recent accurate data on F 2(x,Q) and on F 2 c (x,Q) from HERA at small-x require a more precise treatment of charm production in the global analysis of parton distributions. We improve on existing global QCD analyses by implementing the leptoproduction formalism of Aivazis et al. which represents a natural generalization of the conventional zero mass QCD parton framework to include heavy quark mass effects. We also perform analyses based on the fixed-flavor-number scheme, which is widely used in the literature, and demonstrate their uses and limitations. We discuss the implications of the improved treatment of heavy quark mass effect in practical applications of PQCD and compare our results with recent related works.
Quark Confinement in a Constituent Quark Model

Abstract On the level of an effective quark theory, we define confinement by the absence of quark-antiquark thresholds in correlation functions. We then propose a confining Nambu-Jona-Lasinio-type model. We study the model's phase structure as well as its behavior under extreme conditions, i.e. high temperature and/or high density.
THE WARPED PLANE OF THE CLASSICAL KUIPER BELT

By numerically integrating the orbits of the giant planets and of test particles over a period of four billion years, we follow the evolution of the location of the midplane of the Kuiper belt. The Classical Kuiper belt conforms to a warped sheet that precesses with a 1.9 Myr period. The present-day location of the Kuiper belt plane can be computed using linear secular perturbation theory: the local normal to the plane is given by the theory's forced inclination vector, which is specific to every semimajor axis. The Kuiper belt plane does not coincide with the invariable plane, but deviates from it by up to a few degrees in stable zones. For example, at a semimajor axis of 38 AU, the local Kuiper belt plane has an inclination of 1.9 degrees and a longitude of ascending node of 149.9 degrees when referred to the mean ecliptic and equinox of J2000. At a semimajor axis of 43 AU, the local plane has an inclination of 1.9 degrees and a nodal longitude of 78.3 degrees. Only at infinite semimajor axis does the Kuiper belt plane merge with the invariable plane, whose inclination is 1.6 degrees and nodal longitude is 107.7 degrees. A Classical Kuiper belt object keeps its inclination relative to the Kuiper belt plane nearly constant, even while the plane departs from the trajectory predicted by linear theory. The constancy of relative inclination reflects the undamped amplitude of free oscillation; that is, the homogeneous solution to the forced harmonic oscillator equation retains constant amplitude, even while the inhomogeneous solution cannot be written down accurately because the planetary forcing terms are chaotic. Current observations of Classical Kuiper belt objects are consistent with the plane being warped by the giant planets alone, but the sample size will need to increase by a few times before confirmation exceeds 3σ in confidence. In principle, differences between the theoretically expected plane and the observed plane could be used to infer as yet unseen masses orbiting the Sun, but carrying out such a program would be challenging.
Lambda-determinants and domino-tilings

Consider the 2n-by-2n matrix M=(m"i","j)"i","j"="1^2^n with m"i","j=1 for i,j satisfying |2i-2n-1|+|2j-2n-1|= =4, the @l-determinant of the matrix M (as introduced by Robbins and Rumsey [Adv. Math. 62 (1986) 169-184]) is not well defined. However, if we replace the 0's by t's, we get a matrix whose @l-determinant is well defined and is a polynomial in @l and t. The limit of this polynomial as t->0 is a polynomial in @l whose value at @l=1 is the number of domino-tilings of a 2n-by-2n square.
Shortest paths in directed planar graphs with negative lengths: A linear-space O(n log2n)-time algorithm

We give an O(n log2n)-time, linear-space algorithm that, given a directed planar graph with positive and negative arc-lengths, and given a node s, finds the distances from s to all nodes.
Apodized Pupil Lyot Coronagraphs for Arbitrary Telescope Apertures

In the context of high dynamic range imaging, this study presents a breakthrough for the understanding of apodized pupil Lyot coronagraphs, making them available for arbitrary aperture shapes. These new solutions find immediate application in current, ground-based coronagraphic studies (Gemini, VLT) and in existing instruments (Advanced Electro-Optical System Lyot Project). They also offer the possibility of a search for an on-axis design for the Terrestrial Planet Finder. The unobstructed aperture case has already been solved by C. Aime et al. and R. Soummer et al. Analytical solutions with identical properties exist in the general case and, in particular, for centrally obscured apertures. Chromatic effects can be mitigated with a numerical optimization. The combination of analytical and numerical solutions enables the study of the complete parameter space (central obstruction, apodization throughput, mask size, bandwidth, and Lyot stop size).
The impatient salesperson and the delegation of pricing authority

Abstract Sales agents are impatient relative to owners. If a good fails to sell, the owner still retains possession of that good and can enjoy its services, whereas the agent receives nothing. As a consequence, sales agents prefer a lower price than does an owner. Owners are therefore reluctant to delegate pricing authority to sales agents even when the agents have superior market information. Pricing authority is more likely to be delegated to agents when the owner lacks monopoly power and sells competitively and when the good is a non-durable. Agents who are given pricing authority are less likely to be paid commissions and more likely to be on a straight salary.
Ranking radiotherapy treatment plans using decision-analytic and heuristic techniques.

Abstract Radiotherapy treatment optimization is done by generating a set of tentative treatment plans, evaluating them, and selecting the plan closest to achieving a set of conflicting treatment objectives. The evaluation of potential plans involves making trade-offs among competing possible outcomes. Multiattribute decision theory provides a framework for specifying such trade-offs and using them to select optimal actions. Using these concepts, we have developed a plan-ranking model which ranks a set of tentative treatment plans from best to worst. Heuristics are used to refine this model so that it reflects the clinical condition of the patient being treated and the practice preferences of the physician prescribing the treatment. A figure of merit is computed for each tentative plan and is used to rank the plans. The approach described is very general and can be used for other medical domains having similar characteristics. The figure of merit can also be used as an objective function by computer programs that attempt to automatically generate an optimal treatment plan.
Heterotic phase transitions and singularities of the gauge dyonic string

Abstract Heterotic strings on R 6 × K 3 generically appear to undergo some interesting new phase transition at that value of the string coupling for which one of the six-dimensional gauge field kinetic energies changes sign. An exception is the E 8 × E 8 string with equal instanton numbers in the two E 8 's, which admits a heterotic/heterotic self-duality. In this paper, we generalize the dyonic string solution of the six-dimensional heterotic string to include non-trivial gauge field configurations corresponding to self-dual Yang-Mills instantons in the four transverse dimensions. We find that vacua which undergo a phase transition always admit a string solution exhibiting a naked singularity, whereas for vacua admitting a self-duality the solution is always regular. When there is a phase transition, there exists a choice of instanton numbers for which the dyonic string is tensionless and quasi-anti-self-dual at that critical value of the coupling. For an infinite subset of the other choices of instanton number, the string will also be tensionless, but all at larger values of the coupling.
System identification and adaptive control of the multi-axis bending and twisting process

An adaptive control scheme for the multi-axis bending and twisting process based on system identification of process models is presented. Three system identification methods, the frequency-response, the least-squares, and the singular value decomposition methods, have successfully identified the process models. Control based on these identified process models performed better than control based on the theoretical process models proposed by Luo et al. (1996). The shape errors between the intrinsic geometric quantities of the actual and desired parts are applied to the inverse identified process models to calculate incremental changes in axis commands for subsequent iterations. Comparison with experimental results demonstrates that adaptive control based on the identified process models achieves more rapid convergence of the iterations than the previous approach.
Subexponential groups in 4-manifold topology

We present a new, more elementary proof of the Freedman{Teichner result that the geometric classication techniques (surgery, s{cobordism, and pseudoisotopy) hold for topological 4{manifolds with groups of subexponential growth. In an appendix Freedman and Teichner give a correction to their original proof, and reformulate the growth estimates in terms of coarse geometry.
Religion and contemporary sociological theories

In the late 20th and early 21st centuries, the sociology of religion enjoyed a remarkable growth in both theory and empirical research. The scholarly consensus argues that the early secularization thesis associated with modernization theory was misleading and simplistic, or that it was primarily relevant to northern Europe. Beyond the European framework, there is ample evidence that religion continues to play a major role in society, culture and politics. With urbanization in the developing world, there has come increasing piety and religious revivalism. Religion will be a major factor in political and ideological struggles across the globe in this century. One negative aspect of this focus on political conflict, however, has been an over-concentration on radical Islam and other manifestations of religious violence.
Higher-dimensional Dedekind sums and their bounds arising from the discrete diagonal of the n -cube

Higher-dimensional Dedekind sums are defined as a generalization of a recent one-dimensional probability model of Dilcher and Girstmair to a d-dimensional cube. The analysis of the frequency distribution of diagonal lattice points leads to new formulae in certain special cases, and also to new bounds for the classical Dedekind sums. We define a new correspondence between n-dimensional Dedekind sums and certain convex n-dimensional cones, and we conjecture that these cones have a largest spacial angle of @p/6. Bounds on n-dimensional Dedekind sums are important in the enumeration of lattice points in polytopes, since they are the building blocks for the lattice point enumerator of a polytope. Here, upper bounds for n-dimensional Dedekind sums are expressed in terms of 1-dimensional moments, and various relations among the moments are derived using statistical methods.
Optimal Cruise Altitude for Aircraft Thermal Management

Mission-planning algorithms and trajectory optimization methods for aircraft that use fuel as a heat sink must ensure that fuel temperature limits are not violated at any point in a flight. The problem of determining the cruise altitude that minimizes final fuel tank temperature for jet aircraft that use recirculating fuel to remove waste thermal energy from the aircraft is considered. A heat exchanger transfers energy from the aircraft subsystems to the fuel. A portion of the fuel is burned in a turbojet engine, whereas the remaining unburned fuel is passed through a cooler that transfers some heat from the fuel to the atmosphere. A differential equation that describes the time rate of change of fuel tank temperature is derived based on the principles of conservation of mass and energy. Specific conditions are derived for the cruise altitude that minimizes final tank temperature for flight conditions associated with maximum endurance and range. Expressions are also derived that provide estimates of time ...
Customer knowledge management

Customer knowledge has received little attention in the knowledge management literature. The authors of this exploratory study argue that practices in marketing and customer relationship management have not been able to capture knowledge from customers that comes from social interactions with firm employees. The authors propose a three-step model by which companies can obtain this knowledge. The model's theoretical base comes from the information retrieval and socialization concepts of the knowledge management literature. The paper identifies cultural changes required to make this process successful.
Flap reconstruction in the head and neck: expected appearance, complications, and recurrent disease.

Introduction: Reconstruction of large head and neck operative beds requires moving tissue from one region to another. These flaps may be rotated to cover a defect with the vascular supply intact, or the vascular supply can be transected and re-anastamosed to vessels in the operative bed. This article will review the types of flaps that have been developed to reconstruct treatment sites in the head and neck, describe the expected findings of a flap, and illustrate the appearance of flap complications, especially recurrent tumor. Methods and materials: Thirty-five patients with flap reconstruction were imaged either as a baseline study, or because of clinical suspicion for recurrent tumor. All patients had undergone resection of squamous cell carcinoma of the head and neck, with flap reconstruction. The computed tomographic (CT) and magnetic resonance (MR) images were retrospectively reviewed, with the clinical history and biopsy results, to determine the imaging findings of recurrent disease. Results: Recurrent tumor in the resection bed or flap appeared as a focal mass, usually at the interface of the operative site and the flap. Induration of the fat around the flap, or the fat within the flap, was an indirect finding associated with recurrence. Nodal recurrence, either ipsi or contralateral to the primary, was common. Conclusion: It is important to be aware of the type of flap used to reconstruct head and neck surgical defects. The expected appearance of the flap, and findings associated with recurrent disease are predictable, and are illustrated in the article.
New synthetic pathways to C-glycosides

C-glycopyranosyl compounds exhibit antimicrobial, antifungal, and antitumor activities, most probably based on enzyme inhibition or interference with cell surface recognition phenomena. Recent developments in glycobiology have shown the importance of the glycoside component of glycoproteins for cell recognition and differentiation processes. C-glycosidic analogues of that component would be metabolically stable, and thus offer enhanced therapeutic value. Synthesis of a configurational variety of e.g. amino (glycopyranosyl) methanes is thus an important synthetic goal. The amino group would allow linking the C-glycoside to a variety of scaffolds. Our first approach has been to C-link a C-N synthon (HCN or CH 3 NO 2 ) to the anomeric carbon of a natural carbohydrate. We have realized this with cyanide on glycal, on per-O-acetyl sugars and on cyclic acetal protected glycosyl fluorides, prepared by a novel method. The catalytic hydrogenation of glycosyl cyanides presented challenges and new synthetic possibilities. With CH 3 NO 2 , and 4,6-O-alkylidene protected D-glucose or D-mannose derivatives, we obtained very good yields of cyclic Henry condensation products in THF with a novel catalytic procedure. The novel reduction of the resulting nitro (4,6-O-benzylidene-β-D-glycopyranosyl) methane with Fe 0 /Ni 0 in THF/H 2 O/CO 2 readily supplied amino (4,6-O-benzylidene-β-D--glucopyranosyl) methane, derivatives of which were diastereodiversified into D-allo, D-manno, and D-altro C-glycosides. These approaches fail, however, if prerequisite natural carbohydrate precursors are not available in a given case. Thus, a total synthesis scheme was also initiated. Phthalimido acetaldehyde diethylacetal and 4-penten-2-ol, with TiCl 4 , form 2-methyl-4-chloro-6-phthalimido-methyl tetrahydropyran, which was functionalized into phthalimido (6-deoxy-β-D,L-hexopyranosyl) methanes. Chiral extensions of this method are possible. C-'disaccharides' became available from the Ferrier 'dimerisation' of glycals, and from the hydrogenation of glycosyl cyanides.
Computation of Three-Dimensional Nonlinear Panel Flutter

A recently developed three-dimensional viscous aeroelastic solver is applied to the solution of nonlinear panel flutter. The solution scheme implicitly couples a well validated Navier-Stokes code with a finite-difference procedure for the Von Karman plate equations by employing a subiteration strategy. Both low supersonic, \iM∞ = 1.2, and subsonic, \iM∞ = 0.95, cases are computed. For the supersonic case, the presence of either a laminar or turbulent boundary layer delays the onset of flutter, with higher flutter dynamic pressures resulting for thicker boundary layers. This effect is much less pronounced when the boundary layers are turbulent. In the subsonic case multiple solutions are obtained. The downwardly divergent solution displays a very complex interaction between the laminar boundary layer and the flexible panel that results in significant acoustic radiation from the vibrating panel.
Occupancy and Time-Based Lighting Controls in Open Offices

We present analyses of two years' lighting data in open office areas, controlled by occupant sensors, time scheduling, or wall switches alone. We compare the energy savings using a before-after analysis of time schedulingand a conservative "moving baseline" analysis of both occupant sensing and time scheduling. Both techniques saved energy effectively when no occupants were present compared with wall switches alone. Time scheduling saved from 0.7 to 6.6 percent or an average of about 5 percent. Occupant sensors in similar areas saved from 9.0 to 14.6 percent, with an average of about 10 percent. False triggering of occupant sensors (by passersby) that would have caused energy waste was avoided by the presence of wall switches that positively turned lights off. Variations in occupant schedules and habits affected overall lighting energy use and the appropriateness of different control types. Little savings were found during the normal 8am to 5pm workday from either technology in large offices, but significant savings occurred after hours and on weekends. Our findings contrast with previous results for private offices in which only a single occupant is present, strengthening the evidence that different types of office space can be controlled appropriately with different types of control systems. However, small percentage savings in open areas can result in larger actual savings due to the larger number of fixtures controlled.
Nonlinear neural networks: Principles, mechanisms, and architectures

Abstract An historical discussion is provided of the intellectual trends that caused nineteenth century interdisciplinary studies of physics and psychobiology by leading scientists such as Helmholtz, Maxwell, and Mach to splinter into separate twentieth-century scientific movements. The nonlinear, nonstationary, and nonlocal nature of behavioral and brain data are emphasized. Three sources of contemporary neural network research—the binary, linear, and continuous-nonlinear models—are noted. The remainder of the article describes results about continuous-nonlinear models: Many models of content-addressable memory are shown to be special cases of the Cohen-Grossberg model and global Liapunov function, including the additive, brain-state-in-a-box, McCulloch-Pitts, Boltzmann machine, Hartline-Ratliff-Miller, shunting, masking field, bidirectional associative memory, Volterra-Lotka, Gilpin-Ayala, and Eigen-Schuster models. A Liapunov functional method is described for proving global limit or oscillation theorems for nonlinear competitive systems when their decision schemes are globally consistent or inconsistent, respectively. The former case is illustrated by a model of a globally stable economic market, and the latter case is illustrated by a model of the voting paradox. Key properties of shunting competitive feedback networks are summarized, including the role of sigmoid signalling, automatic gain control, competitive choice and quantization, tunable filtering, total activity normalization, and noise suppression in pattern transformation and memory storage applications. Connections to models of competitive learning, vector quantization, and categorical perception are noted. Adaptive resonance theory (ART) models for self-stabilizing adaptive pattern recognition in response to complex real-time nonstationary input environments are compared with off-line models such as autoassociators, the Boltzmann machine, and back propagation. Special attention is paid to the stability and capacity of these models, and to the role of top-down expectations and attentional processing in the active regulation of both learning and fast information processing. Models whose performance and learning are regulated by internal gating and matching signals, or by external environmentally generated error signals, are contrasted with models whose learning is regulated by external teacher signals that have no analog in natural real-time environments. Examples from sensory-motor control of adaptive vector encoders, adaptive coordinate transformations, adaptive gain control by visual error signals, and automatic generation of synchronous multijoint movement trajectories illustrate the former model types. Internal matching processes are shown capable of discovering several different types of invariant environmental properties. These include ART mechanisms which discover recognition invariants, adaptive vector encoder mechanisms which discover movement invariants, and autoreceptive associative mechanisms which discover invariants of self-regulating target position maps.
Inaccuracies introduced by single width blood pressure cuffs.

Blood pressure cuff dimensions directly affect accuracy of blood pressure measurements. For accurate blood pressure measurements, the width of the cuff must be proportional to arm circumference. A cuff that is too narrow results in falsely high blood pressure values, and a cuff that is too wide results in falsely low values. Some blood pressure standards permit a single width cuff regardless of arm circumference. The purpose of this study was to evaluate whether 12 cm single width cuffs currently permitted by the British Hypertension Society (BHS) standard are sufficiently accurate to pass the Association for the Advancement of Medical Instrumentation (AAMI), BHS, and European Society of Hypertension (ESH) International Protocol (IP1) Working Group standards for accuracy. Each of 101 subjects was tested sequentially with both a single and a proportional width cuff in random order. Auscultatory blood pressure was determined by 2 observers using a double binaural stethoscope. Accuracy was determined by comparing the resulting differences with the AAMI, BHS, and IP1 standards for accuracy. The single width blood pressure cuff failed the AAMI accuracy standards for both systolic blood pressure on large arms and diastolic blood pressure on small and large arms, and overall. The single width cuffs, also, failed the BHS accuracy standards for diastolic BP. In conclusion, these single width cuffs could result in a significant number of people being misdiagnosed and mistreated for hypertension. Therefore, to avoid ‘cuff hypertension’ and ‘cuff hypotension’, the cuff width should be proportional to arm circumference.
Shock tube measurements of branched alkane ignition times and OH concentration time histories

Ignition times and hydroxyl (OH) radical concentration time histories were measured behind reflected shock waves during the oxidation of three branched alkanes: iso-butane (2-methylpropane), iso-pentane (2-methylbutane), and iso-octane (2,2,4-trimethylpentane). Initial reflected shock conditions ranged from 1177 to 2009 K and 1.10 to 12.58 atm with dilute fuel/O2/Ar mixtures varying in fuel concentration from 100 ppm to 1.25% and in equivalence ratio from 0.25 to 2. Ignition times were measured using endwall CH emission and OH concentrations were measured using narrow-linewidth ring-dye laser absorption of the R1(5) line of the OH A-X (0,0) band at 306.7 nm. The ignition times and OH concentration time histories were compared to modeled predictions of seven branched alkane oxidation mechanisms currently available in the literature and the implications of these comparisons are discussed. These data provide a unique database for the validation of detailed hydrocarbon oxidation mechanisms of propulsion related fuels. © 2003 Wiley Periodicals, Inc. Int J Chem Kinet 36: 67–78 2004
One loop tests of higher spin AdS/CFT

Vasiliev’s type A higher spin theories in AdS4 have been conjectured to be dual to the U(N) or O(N) singlet sectors in 3-d conformal field theories with N-component scalar fields. We compare the $ \mathcal{O} $ (N 0) correction to the 3-sphere free energy F in the CFTs with corresponding calculations in the higher spin theories. This requires evaluating a regularized sum over one loop vacuum energies of an infinite set of massless higher spin gauge fields in Euclidean AdS4. For the Vasiliev theory including fields of all integer spin and a scalar with Δ = 1 boundary condition, we show that the regularized sum vanishes. This is in perfect agreement with the vanishing of subleading corrections to F in the U(N) singlet sector of the theory of N free complex scalar fields. For the minimal Vasiliev theory including fields of only even spin, the regularized sum remarkably equals the value of F for one free real scalar field. This result may agree with the O(N) singlet sector of the theory of N real scalar fields, provided the coupling constant in the Vasiliev theory is identified as G N ~ 1/(N − 1). Similarly, consideration of the USp(N) singlet sector for N complex scalar fields, which we conjecture to be dual to the husp(2; 0|4) Vasiliev theory, requires G N ~ 1/(N + 1). We also test the higher spin AdS3 /CFT2 conjectures by calculating the regularized sum over one loop vacuum energies of higher spin fields in AdS3. We match the esult with the $ \mathcal{O} $ (N 0) term in the central charge of the W N minimal models; this requires a certain truncation of the CFT operator spectrum so that the bulk theory contains two real scalar fields with the same boundary conditions.
Renormalization and blow up for charge one equivariant critical wave maps

We prove the existence of equivariant finite time blow-up solutions for the wave map problem from ℝ2+1→S 2 of the form $u(t,r)=Q(\lambda(t)r)+\mathcal{R}(t,r)$ where u is the polar angle on the sphere, $Q(r)=2\arctan r$ is the ground state harmonic map, λ(t)=t -1-ν, and $\mathcal{R}(t,r)$ is a radiative error with local energy going to zero as t→0. The number $\nu>\frac{1}{2}$ can be prescribed arbitrarily. This is accomplished by first “renormalizing” the blow-up profile, followed by a perturbative analysis.
A morera type theorem in the strip

We prove the following result. Let f be a continuous function in the closed infinite strip in complex plane. Suppose the restriction of f to every circle inscribed in the strip extends holomorphically inside the circle. Then f is holomorphic in the open strip.
Dynamic Equilibrium with Liquidity Constraints

This article studies an intertemporal economy with liquidity constrained and unconstrained individuals. We use a stopping time approach to solve the finite horizonconstrained consumption portfolio problem with constant relative risk aversion and to examine the structure of equilibrium. The impact of the constraint on the optimal consumption and the financing portfolio is assessed. The equilibrium state price density is related to the exercise boundary of an American-style contingent claim with nonlinear payoff. This stopping time characterization enables us to prove the existence of an equilibrium and can be implemented numerically. Properties of equilibrium bond and stock returns are examined. Copyright 2003, Oxford University Press.
Cycloaromatization of a solvolytically generated ene-yne-allene

Abstract The diethylphospate ester of 1-(2-ethynylphenyl)-4-trimethylsilyl-4-(trimethylsilyloxy)-2-pentyn-1-ol solvolyzes in 9:1 THF-H 2 O to afford 5-(2-ethynylphenyl)-3-trimethylsilyl-3,4-pentadien-2-one which cyclizes in situ to 1-(2-naphthyl)-1-trimethylsilyl-2-propanone.
Early invasive cervical cancer with pelvic lymph node involvement: To complete or not to complete radical hysterectomy?

The completion of radical hysterectomy in the face of pelvic lymph node involvement presents a dilemma for the surgeon. Some believe it is appropriate to abort the hysterectomy to avoid the excessive morbidity of combined treatment; others believe that completion of the hysterectomy enhances survival. This study was undertaken to define the impact of completing radical hysterectomy followed by adjuvant radiation therapy upon patient survival or pelvic control. Fifteen patients with stage IB and IIA invasive cervical cancer whose radical hysterectomies were aborted solely for reasons of pelvic lymph node involvement were compared to a control group of 15 patients matched for tumor size and number of lymph nodes involved whose radical hysterectomies were completed. Both groups were treated with radiation therapy postoperatively. Survival was not different between groups (P = 0.81). Unexpectedly, local control was slightly improved in the group treated by radiation only (P = 0.127). If radiation therapy is anticipated, completion of radical hysterectomy followed by radiation therapy appears to offer no advantage over radiation therapy with the uterus in place in patients with early-stage invasive cervical cancer and pelvic lymph node involvement.
Intrapartum Maternal Fever and Neonatal Outcome

To the Editor. We read with great interest the article by Lieberman et al1 regarding intrapartum maternal fever related to epidural analgesia and neonatal outcome. The authors' data indicate that intrapartum fever has implications for the fetus. Infants of women who were febrile during labor were more likely to have low 1-minute Apgar scores, to require bag and mask resuscitation, to have hypotonia after delivery, and to require oxygen treatment in the nursery. A finding of greater concern was the increase in the occurrence of seizures among the infants of women with high fever. We studied 73 women who developed fever during labor and …
Type inference against races

The race condition checker rccjava uses a formal type system to statically identify potential race conditions in concurrent Java programs, but it requires programmer-supplied type annotations. This paper describes a type inference algorithm for rccjava. Due to the interaction of parameterized classes and dependent types, this type inference problem is NP-complete. This complexity result motivates our new approach to type inference, which is via reduction to propositional satisfiability. This paper describes our type inference algorithm and its performance on programs of up to 30,000 lines of code.
Australia's National Environmental Legislation: A Response to Early

In, “Australia's National Environmental Legislation and Human/Wildlife Interactions,” published in this journal in 2008 (Vol. 11(2):101–155), Gerard Early describes key elements of the Australian G...
One-pot cascade Michael–Michael–Aldol condensation for diastereoselective synthesis of nitro-substituted cyclohexanes

A one-pot reaction of nitroalkenes and enones was developed for the preparation of nitro-vinyl-substituted cyclohexanes, which could be simply converted into poly-N-heterocycles.
Non-LTE, Relativistic Accretion Disk Fits to 3C 273 and the Origin of the Lyman Limit Spectral Break

We fit general relativistic, geometrically thin accretion disk models with non-LTE atmospheres to near-simultaneous multiwavelength data of 3C 273, extending from the optical to the far-ultraviolet. Our model fits show no flux discontinuity associated with a hydrogen Lyman edge, but they do exhibit a spectral break which qualitatively resembles that seen in the data. This break arises from relativistic smearing of Lyman emission edges which are produced locally at tens of gravitational radii in the disk. We discuss the possible effects of metal line blanketing on the model spectra, as well as the substantial Comptonization required to explain the observed soft X-ray excess. Our best-fit accretion disk model underpredicts the near-ultraviolet emission in this source and also has an optical spectrum which is too red. We discuss some of the remaining physical uncertainties and suggest in particular that an extension of our models to the slim disk regime and/or including nonzero magnetic torques across the innermost stable circular orbit may help resolve these discrepancies.
The Allylic Trihaloacetimidate Rearrangement

Sigmatropic rearrangements of allylic systems have found wide application in organic synthesis, with carbon-carbon bond forming rearrangements such as the Cope and Claisen rearrangements being particularly well known. The sigmatropic rearrangement of allylic imidates offers a valuable entry into the preparation of protected allylic amines. Conversion of an imidate to the amide is essentially irreversible, with the transformation of the imidate to the amide being exothermic by about 15 kcal/mol. Since the discovery of the thermal allylic imidate rearrangement in 1937, a number of systems have been investigated for the practical preparation of allylic amines by this route. However, it was the discovery and development of the rearrangement of allylic trichloroacetamidates that demonstrated the utility of this synthetic method. This chapter is limited to the discussion of allylic trichloro- and trifluoracetamidate rearrangements. The [3,3]-sigmatropic rearrangement of trichloracetamidates (now called the Overman rearrangement) or trifluoroacetimidates can be carried out either thermally or with Hg(II) or Pd(II) catalysis, The scope of this rearrangement is such that primary, secondary, and tertiary allylic amides are readily accessible, thus providing a wide entry into nitrogen-containing products such as amino sugars, nucleotides, peptides, etc. The Overman rearrangement has found extensive application in the total synthesis of natural products. The recent development of the use of chiral Pd(II) catalysts bodes well for amine synthesis. Keywords: allylic trihaloacetimidates; rearrangement; mechanism; trichloractimidates; trifluoracetimidates; thermal rearrangements; catalyzed rearrangements; chiral imidates; allyl amines; allylic alcohols; comparison of methods; natural products; mechanisms; stereochemistry; transition metals