cssi/SciSciGPT-SciSciNet huggingface dataset:
Managing upward, downward and outward: Networks, hierarchical relationships and performance

It is particularly difficult, but also valuable, to try to estimate the relative contributions of different managerial functions to the outcomes of public programs. Building from a formal treatment of public management and performance, this study explores this research task with empirical analyses of several hundred public organizations and their top managers over a five-year period. Using Moore's distinction among managing upward toward political principals, downward toward organizational agents and outward toward the networked environment, we examine managerial impacts on ten different performance criteria. Findings validate the points that these three functions are distinct, public management has performance-relevant impacts and managerial networking outward can be an important contributor to the achievement of public objectives.
Distance preserving embeddings for general n-dimensional manifolds

Low dimensional embeddings of manifold data have gained popularity in the last decade. However, a systematic finite sample analysis of manifold embedding algorithms largely eludes researchers. Here we present two algorithms that embed a general n-dimensionalmanifold into Rd (where d only depends on some key manifold properties such as its intrinsic dimension, volume and curvature) that guarantee to approximately preserve all interpoint geodesic distances.
Chromium(III) catalyzed synthesis of allenes from propargyl derivatives via a carbometalation–elimination sequence

The syn-carbometalation/syn-elimination of propargyl substrates to form allenes has been achieved using cationic chromium(III) catalysts activated by alkylaluminums. The mechanism and scope of this transformation are presented.
Electromagnetic properties of impact-generated plasma, vapor and debris

Plasma, vapor and debris associated with an impact or explosive event have been demonstrated in the laboratory to produce radiofrequency and optical electromagnetic emissions that can be diagnostic of the event. Such effects could potentially interfere with communications or remote sensing equipment if an impact occurred, for example, on a satellite. More seriously, impact generated plasma could end the life of a satellite by mechanisms that are not well understood and not normally taken into account in satellite design. For example, arc/discharge phenomena resulting from highly conductive plasma acting as a current path across normally shielded circuits may have contributed to the loss of the Olympus experimental communications satellite on August 11, 1993. The possibility of significant storm activity during the Leonid meteor showers of November 1998, 1999 and 2000 (impact velocity, 72 km/s) has heightened awareness of potential vulnerabilities from hypervelocity electromagnetic effects to orbital assets. The concern is justified. The amount of plasma, electrostatic charge and the magnitude of the resulting currents and electric fields scale nearly as the cube of the impact velocity (∝ ν2.6). Even for microscopic Leonid impacts, the amount of plasma approaches levels that could be dangerous to spacecraft electronics. The degree of charge separation that occurs during hypervelocity impacts scales linearly with impactor mass. The resulting magnetic fields increase linearly with impactor radius and could play a significant role in our understanding of the paleomagnetism of planetary surfaces.
Structured programming in a production programming environment

This paper discusses how structured programming methodology has been introduced into a large production programming organization using an integrated but flexible approach. It next analyzes the advantages and disadvantages of each component of the methodology and presents some quantitative results on its use. It concludes with recommendations based on this generally successful experience, which could be useful to other organizations interested in improving reliability and productivity.
Pulse-based dead-time compensator for PWM voltage inverters

The dead time necessary to prevent the short circuit of the power supply in pulsewidth-modulated (PWM) voltage inverters results in output voltage errors. Although individually small, when accumulated over an operating cycle, the voltage errors are sufficient to distort the applied PWM signal. This paper presents a method to correct for the dead-time errors. The pulse-based dead-time compensator (PBDTC) is less hardware- and software-intensive than other dead-time compensation methods providing a low-cost solution. The pulse-based technique is developed by analyzing the effects of dead time on a pulse-by-pulse basis and correcting each pulse accordingly. The technique is evaluated through simulation and experimental results. Other compensation methods are evaluated, and the results compared with the pulse-based technique. This comparison indicates previous methods can produce magnitude and phase errors in the applied terminal voltage, whereas the proposed method compensates for the dead time without significant magnitude and phase errors in the terminal voltage of PWM voltage source inverters.
Does global slack matter more than domestic slack in determining U.S. inflation

Abstract This paper employs a structural model to estimate whether global output gap has become an important determinant of U.S. inflation dynamics. The results provide support for the relevance of global slack as a determinant of U.S. inflation after 1985.
Entropic self-assembly of freely rotating polyhedral particles confined to a flat interface

The self-assembly of hard polyhedral particles confined to a flat interface is studied using Monte Carlo simulations. The particles are pinned to the interface by restricting their movement in the direction perpendicular to it while allowing their free rotations. The six different polyhedral shapes studied in this work are selected from a family of truncated cubes defined by a truncation parameter, s, which varies from cubes (s = 0) via cuboctahedra (s = 0.5) to octahedra (s = 1). Our results suggest that shapes with small values of s show square-like behavior whereas shapes with large values of s tend to show more disc-like behavior. At an intermediate value of s = 0.4, the phase behavior of the system shows both square-like and disc-like features. The results are also compared with the phase behavior of 3D bulk polyhedra and of 2D rounded hard squares. Both comparisons reveal key similarities in the number and sequence of mesophases and solid phases observed. These insights on 2D entropic self-assembly of polyhedral particles is a first step toward understanding the self-assembly of particles at fluid–fluid interfaces, which is driven by a complex interplay of entropic and enthalpic forces. A first-order analysis of the particle-surface energies associated with a fluid–fluid interface indicates that such enthalpic interactions will be particularly important in determining particle orientation behavior at low to intermediate concentrations.
Hexafluoroisopropanol as a unique solvent for stereoselective iododesilylation of vinylsilanes.

Stereoselective preparation of iodoalkenes from vinylsilanes is described. 1,1,1,3,3,3-Hexafluoroisopropanol serves as a unique solvent that ensures high yields and stereoselectivities in the iododesilylation of a variety of functionalized substrates.
Voltage-gated Proton Channels

Voltage-gated proton channels, HV1, have vaulted from the realm of the esoteric into the forefront of a central question facing ion channel biophysicists, namely, the mechanism by which voltage-dependent gating occurs. This transformation is the result of several factors. Identification of the gene in 2006 revealed that proton channels are homologues of the voltage-sensing domain of most other voltage-gated ion channels. Unique, or at least eccentric, properties of proton channels include dimeric architecture with dual conduction pathways, perfect proton selectivity, a single-channel conductance approximately 10(3) times smaller than most ion channels, voltage-dependent gating that is strongly modulated by the pH gradient, ΔpH, and potent inhibition by Zn(2+) (in many species) but an absence of other potent inhibitors. The recent identification of HV1 in three unicellular marine plankton species has dramatically expanded the phylogenetic family tree. Interest in proton channels in their own right has increased as important physiological roles have been identified in many cells. Proton channels trigger the bioluminescent flash of dinoflagellates, facilitate calcification by coccolithophores, regulate pH-dependent processes in eggs and sperm during fertilization, secrete acid to control the pH of airway fluids, facilitate histamine secretion by basophils, and play a signaling role in facilitating B-cell receptor mediated responses in B-lymphocytes. The most elaborate and best-established functions occur in phagocytes, where proton channels optimize the activity of NADPH oxidase, an important producer of reactive oxygen species. Proton efflux mediated by HV1 balances the charge translocated across the membrane by electrons through NADPH oxidase, minimizes changes in cytoplasmic and phagosomal pH, limits osmotic swelling of the phagosome, and provides substrate H(+) for the production of H2O2 and HOCl, reactive oxygen species crucial to killing pathogens.
On the Topology of Kac–Moody groups

We study the topology of spaces related to Kac–Moody groups. Given a Kac–Moody group over $$\mathbb C $$ , let $$\text {K}$$ denote the unitary form with maximal torus $${{\mathrm{T}}}$$ having normalizer $${{\mathrm{N}}}({{\mathrm{T}}})$$ . In this article we study the cohomology of the flag manifold $$\text {K}/{{{\mathrm{T}}}}$$ as a module over the Nil-Hecke algebra, as well as the (co)homology of $$\text {K}$$ as a Hopf algebra. In particular, if $$\mathbb F $$ has positive characteristic, we show that $$\text {H}_*(\text {K},\mathbb F )$$ is a finitely generated algebra, and that $$\text {H}^*(\text {K},\mathbb F )$$ is finitely generated only if $$\text {K}$$ is a compact Lie group . We also study the stable homotopy type of the classifying space $$\text {BK}$$ and show that it is a retract of the classifying space $$\text {BN(T)}$$ of $${{\mathrm{N}}}({{\mathrm{T}}})$$ . We illustrate our results with the example of rank two Kac–Moody groups.
Violent Conflict and the Spread of HIV/AIDS in Africa

It has been widely speculated that violent conflict acts as a key contributor to the transmission of human immunodeficiency virus (HIV). Yet to date no empirical examination of the conflict-HIV relationship has been conducted. Drawing on work in political science and public health, we set forth a theoretical framework for understanding this potential relationship and go on to present data on the spatio-temporal dispersion of HIV/AIDS in 43 African countries during the period from 1997 to 2005. We then assess the association between domestic and international conflict and levels of HIV/AIDS infection while controlling for a range of other influential factors. Our analyses support a clear positive relationship between both international and domestic conflict and climbing HIV/AIDS prevalence, as well as significant palliative effects for education and economic development on the incidence of HIV/AIDS.
Communicating with dementia patients on hospice

There are distinct differences in caring for the “typical” hospice patient as opposed to the hospice patient who has Alzheimer’s disease. The entire hospice team, from volunteers to physicians, can...
Measurement of diffusion in fluid systems - Applications to the supercritical fluid region

In this article, the experimental procedures that are applicable to the measurement of diffusion in supercritical fluid solutions will be reviewed. This topic is of great importance to the proper design of advanced aircraft and turbine fuels, since the fuels on these aircraft may sometimes operate under supercritical fluid conditions. More specifically, we will consider measurements of the binary interaction diffusion coefficient Z>12 of a solute (species 1) and the solvent (species 2). In this discussion the supercritical fluid will be species 2, and the solute, species 1, will be at a relatively low concentration, sometimes approaching infinite dilution. After a brief introduction to the concept of diffusion, we will discuss in detail the use of chromatographic methods, and then briefly treat light scattering, nuclear magnetic resonance spectra, and physical methods.
CP Violation: Past, Present, and Future

We discuss the history of CP violation and its manifestations in kaon physics, its explanation in terms of phases of the Cabibbo-Kobayashi-Maskawa matrix describing charge-changing weak quark transitions, predictions for experiments involving B mesons, and the light it can shed on physics beyond the Standard Model.
Present Epoch Plus — an X-ray survey for cosmology

This paper summarizes some cosmologically interesting measurements which are uniquely possible in the hard X-ray band and presents a mission concept capable of achieving them. The Present Epoch Plus mission will achieve a surface brightness sensitivity of better than 1% per square degree in the 2–10 keV band, and create a catalog of ∽ 106 sources. About 160,000 extragalactic sources are expected to be detected in the 2–10 keV band, providing an all sky survey with nearly uniform selection effects 10 times deeper than existing or planned surveys. The PEP concept can be achieved within the size and budgetary constrraints of a NASA Medium Explorer (MIDEX) mission.
Growing Broilers for Maximum Returns

This article considers how producers of broilers may maximize returns above direct or cash costs. The author analyzes the effect of increased feed efficiency upon the weight to which it pays to feed broilers. His analysis indicates that the most profitable weight depends upon whether producers are interested in maximizing returns from an individual lot or from broilers raised continuously during the year. Broiler production is a conspicuous example of an industry that has adopted improved production techniques rapidly, to make possible a greatly expanded output at lower relative costs.
Dynamical constraints on the Local Group from the CMB and 2MRS dipoles

We place constraints on the dynamics of the Local Group (LG) by comparing the dipole of the cosmic microwave background (CMB) with the peculiar velocity induced by the Two Micron All-Sky Redshift Survey galaxy sample. The analysis is limited by the lack of surveyed galaxies behind the zone of avoidance (ZoA). We therefore allow for a component of the LG velocity due to unknown mass concentrations behind the ZoA, as well as for an unknown transverse velocity of the Milky Way relative to the Andromeda galaxy. We infer extra motion along the direction of the Galactic Centre (where Galactic confusion and dust obscuration peaks) at the 95 per cent significance level. With a future survey of the ZoA it might be possible to constrain the transverse velocity of the Milky Way relative to Andromeda.
A Markov chain sequence generator for power macromodeling

In this paper, we present a novel sequence generator based on a Markov chain (MC) model. Specifically, we formulate the problem of generating a sequence of vectors with given average input probability p, average transition density d, and spatial correlation s as a transition matrix computation problem, in which the matrix elements are subject to constraints derived from the specified statistics. We also give a practical heuristic that computes such a matrix and generates a sequence of l n-bit vectors in O(nl+n/sup 2/) time. Derived from a strongly mixing MC, our generator yields binary vector sequences with accurate statistics, high uniformity, and high randomness. Experimental results show that our sequence generator can cover more than 99% of the parameter space. Sequences of 2000 48-bit vectors are generated in less than 0.05 s, with average deviations of the signal statistics p,d, and s equal to 1.6%, 1.8%, and 2.8%, respectively. Our generator enables the detailed study of power macromodeling. Using our tool and the ISCAS'85 benchmark circuits, we have assessed the sensitivity of power dissipation to the three input statistics p,d, and s. Our investigation reveals that power is most sensitive to transition density, while only occasionally exhibiting high sensitivity to signal probability and spatial correlation. Our experiments also show that input signal imbalance can cause estimation errors as high as 100% in extreme cases, although errors are usually within 25%.
A COMPARATIVE ANALYSIS OF THE EU-MOROCCO FTA VS. MULTILATERAL LIBERALIZATION

An applied general equilibrium model with oligopoly and scale economies, based on detailed plant-level data, is used to contrast the impacts of the Morocco-EU free trade area (FTA) to multilateral trade liberalization on Morocco’s economy. Simulation results show that the FTA agreement is likely to have adverse effects on Morocco due to: (a) deteriorating terms of trade, (b) reductions in output per firm in industries dominated by scale economies, (c) diversion of imports away from relatively low cost, non-EU suppliers, and (d) potentially adverse effects on the aggregate demand for labor which could exacerbate already high levels of unemployment. We contrast this FTA with a multilateral liberalization scenario along the lines of those proposed under the Doha Development Round and find this to be more beneficial to Morocco, despite the associated income transfer from the EU to Morocco. The difference may be attributed to: (a) lesser terms of trade losses, (b) positive scale effects, (c) non-preferential liberalization of imports into Morocco, and (d) a positive impact on aggregate labor demand and hence unemployment. We conclude that Morocco would be better off pursuing trade liberalization in the multilateral arena. JEL classification: F12, F14, F15 Keywords: Applied general equilibrium; Market Structure; Trade liberalization; Developing economies; Morocco
Emittance compensation studies of photoinjector beams with angular momentum

Beam dynamics studies on the FNPL photoinjector that seek to optimize the transport of intense electron beams with large values of canonical angular momentum have been performed. These studies investigate the effect of solenoid emittance compensation on beams that evolve under the combined influence of intense space charge forces and large angular momentum. We present details of experimental measurements and supporting simulations of beam envelope evolution.
Laser-Induced Disturbance with Application to a Low Reynolds Number Flow

A novel technique is discussed for nearly instantaneous generation of a strong volumetric disturbance in a flow. This technique utilizes the pulsed energy from an excimer laser to photodissocia te a seed gas. Under prescribed conditions, the excess energy associated with the photodissociation is sufficient for producing a severe disturbance. Because it is possible to control the strength and shape of the disturbance, laser energy deposition may become an important tool in experimental fluid dynamics. The effect of laser energy deposition on an inviscid and two low Reynolds number, two-dimensional, supersonic flows is analyzed computationally using the full, unsteady Navier-Stokes equations. There are large differences between the inviscid and viscous flows, with the latter cases showing the presence of a normal-oblique, unsteady shock wave system and of several flow separation regions. It requires 5-10 jis for separation to develop, and the separation is associated only with the upstream edge of the disturbance.
Twin Screw Extrusion of DDGS-Based Aquaculture Feeds

Six isocaloric (3.65 kcal/g), isonitrogenous (35% dry-basis [db] protein), ingredient blends were prepared with 0, 17.5, 20, 22.5, 25, and 27.5% distiller’s dried grains with solubles (DDGS) and other ingredients (soybean meal, corn, fish meal, whey, soybean oil, vitamin and mineral mix). The blends were moisture balanced to 15% db, then extruded in a twin screw extruder using a 2 mm die at 190 rpm, and a 3 mm die at 348 rpm. Analyses of the extrudates included moisture content, expansion ratio, unit density, bulk density, sinking velocity, color (L*, a*, and b*), water absorption, water solubility, and pellet durability indices. Increasing the DDGS level from 0 to 17.5% db resulted in decreased expansion ratios by 14.8 and 23.5% for the products extruded using a 2 and 3 mm die, respectively. No significant difference in expansion ratio existed for DDGS levels between 17.5 and 27.5% db for either die. The water solubility index (WSI) of the extrudates increased (25.2 and 24.0%) as the DDGS increased from 0 to 27.5% db for each die. The 0% DDGS had the highest expansion ratio and the lowest unit density, bulk density, and sinking velocity. The extrudates that contained 20 and 27.5% DDGS had the highest durability and sinking velocity values.
Influence of a large woody debris obstruction on three-dimensional flow structure in a meander bend

Abstract A field experiment has been conducted to assess the influence of a large woody debris (LWD) obstruction on three-dimensional flow through a meander bend of a small stream in east central Illinois. Previous studies in unobstructed meander bends have shown that flow through a curved channel should develop a coherent three-dimensional structure characterized by large-scale helical motion. Many meander bends are complicated by naturally occurring persistent obstacles, such as LWD, that have the potential to profoundly disrupt flow structure. The results of this study show that the LWD obstruction systematically influences the three-dimensionality of flow through the bend, particularly the position of the high-velocity core and the development of helicity. The high-velocity core is positioned in the center of the channel upstream of and near the bend apex, but as flow approaches the LWD, it is steered toward the inner bank by the obstruction. Evolving helicity in the upstream portion of the bend is amplified by abrupt turning of the flow induced by the LWD. As the flow moves past the LWD, helicity diminishes rapidly and may even reverse its pattern of rotation. The net effect of the LWD obstruction is to reduce near-bank velocities along the outer bank downstream of the bend apex—a critical locus for bank erosion in meander bends. Given the persistence of the LWD obstruction, it probably has an important local influence on bend migration and evolution.
The Lincoln WAND

An ultrasonic position-sensing device has been designed which will allow a computer to determine periodically the x, y, and z coordinates of the tip of a pen-sized wand. The device can replace the lightpen and RAND Tablet for 2-D work, and extend the usefulness of such devices by virtue of the extra dimension available. The extremely large working space in which the WAND can operate allows it to be used for an entirely new set of pointing functions not directly connected with a display as well as the normal display control functions.
Learning Your Comparative Advantages

We introduce an equilibrium labor market model, where workers gradually learn about their unobserved production abilities. While engaged in a productive activity (occupation), workers observe their output and extract information that allows them to make inferences about their unobserved aptitudes. Because workers are learning about themselves, their output informs them not only about their productivity in their current occupation, but about their likely productivity in other occupations as well. As workers acquire more information, they self-select into the occupations in which they expect to perform best, and their wages increase. Returns to experience here capture improved job selection by workers as they sort through occupations and learn
A stochastic theory of grain growth

Abstract A stochastic theory of normal grain growth is proposed. The model is based on the concept that the migration of kinks and ledges should cause a Brownian motion of the grain boundary. This motion results in a drift of the grain size distribution to larger sizes. The kinetics of grain growth is thus related to the kinetics of kinks and ledges; specifically, via the rates of nucleation, recombination and sink annihilation. A variety of growth exponents are obtained from a scaling analysis, but only one universal grain size distribution is applicable in all cases. The specific predictions of this model are in total agreement with the recent computer simulations of domain growth, and are consistent with experimental observations of normal grain growth.
Steady-State Dynamic Behavior of a Flexible Rotor With Auxiliary Support From a Clearance Bearing

This paper investigates the steady-state responses of a rotor system supported by auxiliary bearings in which there is a clearance between the rotor and the inner race of the bearing. A simulation model based upon the rotor of a production jet engine is developed and its steady-state behavior is explored over a wide range of operating conditions for various parametric configurations. Specifically, the influence of rotor imbalance, clearance, support stiffness and damping is studied. Bifurcation diagrams are used as a tool to examine the dynamic behavior of this system as a function of the aforementioned parameters. The harmonic balance method is also employed for synchronous response cases. The observed dynamical responses is discussed and some insights into the behavior of such systems are presented.
ADDITIVE VERSUS PROPORTIONAL PEST DAMAGE FUNCTIONS: WHY ECOLOGY MATTERS

Economic analyses of pests typically assume damage is either additively separable from pest free yield or proportional to it. This paper describes the ecological assumptions required for additive and proportional damage functions to demonstrate that both specifications are reasonable. Ecological research supports a proportional damage function for competitive pests such as weeds, while for insect pests the appropriate damage function depends on the level of pest free yield. Theoretical analysis identifies differences between additive and proportional damage functions in terms of the impact of pest control on output variance and the concavity of output in the pest control input.
The Large N limit of superconformal field theories and supergravity

We show that the large-N limits of certainconformal field theories in various dimensions includein their Hilbert space a sector describing supergravityon the product of anti-de Sitter spacetimes, spheres, and other compact manifolds. This is shown bytaking some branes in the full M/string theory and thentaking a low-energy limit where the field theory on thebrane decouples from the bulk. We observe that, in this limit, we can still trust thenear-horizon geometry for large N. The enhancedsupersymmetries of the near-horizon geometry correspondto the extra supersymmetry generators present in thesuperconformal group (as opposed to just the super-Poincaregroup). The 't Hooft limit of 3 + 1 N = 4 super-Yang–Mills at the conformal pointis shown to contain strings: they are IIB strings. Weconjecture that compactifications of M/string theory on various anti-de Sitterspacetimes is dual to various conformal field theories.This leads to a new proposal for a definition ofM-theory which could be extended to include fivenoncompact dimensions.
Dietary Factors Modulate Helicobacter-associated Gastric Cancer in Rodent Models:

Since its discovery in 1982, the global importance of Helicobacter pylori–induced disease, particularly in developing countries, remains high. The use of rodent models, particularly mice, and the unanticipated usefulness of the gerbil to study H. pylori pathogenesis have been used extensively to study the interactions of the host, the pathogen, and the environmental conditions influencing the outcome of persistent H. pylori infection. Dietary factors in humans are increasingly recognized as being important factors in modulating progression and severity of H. pylori–induced gastric cancer. Studies using rodent models to verify and help explain mechanisms whereby various dietary ingredients impact disease outcome should continue to be extremely productive.
Diagrammatic expansion of the Casimir energy in multiple reflections: Theory and applications

We develop a diagrammatic representation of the Casimir energy of a multibody configuration. The diagrams represent multiple reflections between the objects and can be organized by a few simple rules. The lowest-order diagrams (or reflections) give the main contribution to the Casimir interaction which proves the usefulness of this expansion. Among some applications of this, we find analytical formulae describing the interaction between edges, i.e. semi-infinite plates, where we also give a first example of blocking in the context of the Casimir energy. We also find the interaction of edges with a needle and describe analytically a recent model of the repulsion due to the Casimir interaction.
Anisotropic flow in AuAu and CuCu at 62 GeV and 200 GeV

We present STAR's measurements of directed flow ( v 1 ) and elliptic flow ( v 2 ) for charged hadrons in AuAu collisions at 62 and 200 GeV, as a function of pseudorapidity, p t and centrality. v 2 results in CuCu collisions at 200 GeV are also presented.
Intertemporal regulatory tasks and responsibilities for greenhouse gas reductions

A number of jurisdictions are in the process of establishing regulatory systems to control greenhouse gas emissions that will include as a major component a cap-and-trade system. Both short-term and long-term emissions reduction goals are often established, as California does for the years 2020 and 2050, but little attention has yet been focused on establishing annual emissions targets for the intervening years. We develop recommendations for how these annual targets—which we collectively term a “compliance pathway”—can be set, as well as what flexibility sources should have to adjust to changing or unexpected circumstances in light of cost uncertainties. Existing cap-and-trade programs provide limited guidance on the choice of compliance pathways or on mechanisms for flexibility along them. We consider environmental effectiveness, efficiency, equity, and adaptability as appropriate criteria by which these intertemporal policy alternatives should be judged. We also consider how the strategic context of global emissions reduction may affect the design. Borrowing constraints that are likely to be present in any regulatory system affect our recommendations. We recommend that some allowances intended for future years be auctioned early, and that sources be allowed to use them early. We also find that a three-year compliance period can have substantial benefit over a one-year period. Furthermore, we find that many sources of cost uncertainty suggest a compliance pathway characterized by increasing emission decrements along it. This can be approximated by discrete linear segments, and the latter may fit better with ongoing global negotiations.
The heavy ion injection scheme for RHIC

The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory has a multicomponent injection system. The RHIC requires very heavy ions such as /sup 179//sub 79/Au to be injected fully stripped of atomic electrons, at a kinetic energy of approximately 10 GeV/nucleon. However, the heavy ions are produced initially at a negative ion source and accelerated first in a 15-MV tandem. These partially stripped ions have a kinetic energy of approximately 1 MeV/nucleon on leaving the tandem. In order to achieve the injection requirements for the RHIC, the partially stripped ions are accelerated in the booster (currently under construction) and pass through a stripping foil on their way to the Alternating Gradient Synchrotron (AGS), where they are further accelerated before injection into the RHIC. Recent theoretical calculations have shown quite convincingly that very heavy ions with two electrons in the filled K-shell can be accelerated with negligible loss in the AGS. >
A parametric study of a flexible ocean tower

Abstract Offshore compliant structures are a valuable and attractive option for conditions involving operation in deep water because of their reduced structural weight. One class of offshore compliant structure is the articulated tower, which does not use guylines or tethers to provide a restoring force; rather, the articulated tower relies on a large buoyancy moment to maintain its orientation. This paper examines a continuous, elastic model of an articulated tower undergoing planar motion. Forces due to gravity, buoyancy, and waves are considered, and the nonlinear governing equations of motion derived using Hamilton's Principle. These equations of motion are discretized using the finite difference method, and solved numerically. A proposed simplification of the derived elastic equations is presented, and the simplified model is shown to provide a good upper bound on the motion and a good picture of the qualitative behavior. A parameter study on the tower system is performed, demonstrating the stability of the tower system in the presence of different environmental loads and under different tower configurations.
Action of atomic fluorine on E- and Z-2-butene

Abstract Irradiation of N2F4(NF2) with E- and Z-2 butene in the gas phase leads to addition of F and NF2 across the double bond in a non-stexeoselective manner and abstraction of H to give 2- butenyl radicals which interconvert rapidly before being trapped by NF2 to yield E- and Z-1- difluoroamino-2-butene and 3-difluoramino-1-butene. The configurational instability of the 2- butenyl radicals is attributed to the exothermicity of F atom abstraction. These results are contrasted with those of other workers who observed that in condensed phase reactions abstraction by t -butoxy radical leads to 2-butenyl radicals which are configurationally stable.
Three Manifold Mutations Detected by Heegaard Floer Homology

Given a self-diffeomorphism h of a closed, orientable surface S and an embedding f of S into a three-manifold M, we construct a mutant manifold N by cutting M along f(S) and regluing by h. We will consider whether there are any gluings such that for any embedding, the manifold and its mutant have isomorphic Heegaard Floer homology. In particular, we will demonstrate that if the gluing is not isotopic to the identity, then there exists an embedding of S into a three-manifold M such that the rank of the non-torsion summands of the Heegaard Floer homology of M differs from that of its mutant. We will also show that if the gluing map is isotopic to neither the identity nor the genus-two hyperelliptic involution, then there exists an embedding of S into a three-manifold M such that the total rank of the Heegaard Floer homology of M differs from that of its mutant.
The Performance Effects of Congruence Between Product Competitive Strategies and Purchasing Management Design

The objective of this study is to examine a performance contingency effect between product competitive strategy and organization design using an archival approach. Specifically, this study examines a sample of 194 firms from 20 industries based on the data collected by Center for Advanced Purchasing Studies (CAPS) in its benchmarking surveys between 1989-1994 and links the benchmarking data to the COMPUSTAT (Standard & Poor's) financial data of these firms. The results of the study reveal a contingency relationship among product competitive strategies, purchasing design characteristics, and overall firm financial performance (return on assets). Specifically, the nature of this contingency relationship suggests that a firm's product competitive strategy must be enabled with a complementary design in purchasing management to promote firm performance. Given the growing practice of benchmarking at the functional level, this study also examines whether or not a firm achieving a congruency in product strategy and design will necessarily enjoy higher operational efficiency at the purchasing management level. The results show that this is true only under specific conditions. The implications of the preceding findings are discussed accordingly.
Synthesis of pure alumina mesoporous materials

Alumina mesophases have been synthesized by reacting aluminum alkoxides and carboxylic acids with controlled amounts of water in low-molecular-weight alcoholic solvents. Calcination of these materials yields aluminas that are thermally stable to 1073 K and contain randomly ordered pores. Specific surface areas as high as 710 m2/g and narrow pore size distributions centered at 20 A that do not contain “zeolitic” micropores are exhibited by the calcined solids.
Sustainable Reputations with Rating Systems

Abstract In a product choice game played between a long lived seller and an infinite sequence of buyers, we assume that buyers cannot observe past signals. To facilitate the analysis of applications such as online auctions (e.g. eBay), online shopping search engines (e.g. BizRate.com) and consumer reports, we assume that a central mechanism observes all past signals, and makes public announcements every period. The set of announcements and the mapping from observed signals to the set of announcements is called a rating system. We show that, absent reputation effects, information censoring cannot improve attainable payoffs. However, if there is an initial probability that the seller is a commitment type that plays a particular strategy every period, then there exists a finite rating system and an equilibrium of the resulting game such that, the expected present discounted payoff of the seller is almost his Stackelberg payoff after every history. This is in contrast to Cripps, Mailath and Samuelson (2004) [5] , where it is shown that reputation effects do not last forever in such games if buyers can observe all past signals. We also construct finite rating systems that increase payoffs of almost all buyers, while decreasing the sellerʼs payoff.
Transport of Accelerator Produced Neutrons in a Concrete Room

The production of photoneutrons by electron accelerators is an unavoidable process at operating energies above about 10 MeV. These photoneutrons create problems in shielding, personnel protection, and induced radioactivity. This paper attempts to describe the neutron field spectral and intensity distributions. The initial spectrum and modifying effects of photon shielding materials and concrete room shielding are considered. The relative yields of neutrons and photons as a function of the primary electron energy are described. Both experimental and Monte Carlo results are presented. It is shown that the average energy of the neutron spectrum is a useful parameter for shielding calculations, fluence-to-dose equivalent conversions, and spectral degradation calculations.
Cycles in fossil diversity

With the posthumously published A Compendium of Fossil Marine Animal Genera, Jack Sepkoski initiated a new wave in palaeontology: the exploration of major patterns in the history of life as recorded by compilations of taxonomic data. This database, which records first and last stratigraphic appearances of over 36,000 marine genera, has been reanalysed in the light of the latest stratigraphic time scales, and a previously unrecognized 62-million-year cycle in the diversity of fossil genera emerges. As yet there is no explanation, but various models involving climate, environment, geological and astrophysical factors should provide testable predictions to help solve the mystery. It is well known that the diversity of life appears to fluctuate during the course of the Phanerozoic, the eon during which hard shells and skeletons left abundant fossils (0–542 million years ago). Here we show, using Sepkoski's compendium1 of the first and last stratigraphic appearances of 36,380 marine genera, a strong 62 ± 3-million-year cycle, which is particularly evident in the shorter-lived genera. The five great extinctions enumerated by Raup and Sepkoski2 may be an aspect of this cycle. Because of the high statistical significance we also consider the contributions of environmental factors, and possible causes.
Tools for Targeted Genome Engineering of Established Drosophila Cell Lines

We describe an adaptation of φC31 integrase–mediated targeted cassette exchange for use in Drosophila cell lines. Single copies of an attP-bounded docking platform carrying a GFP-expression marker, with or without insulator elements flanking the attP sites, were inserted by P-element transformation into the Kc167 and Sg4 cell lines; each of the resulting docking-site lines carries a single mapped copy of one of the docking platforms. Vectors for targeted substitution contain a cloning cassette flanked by attB sites. Targeted substitution occurs by integrase-mediated substitution between the attP sites (integrated) and the attB sites (vector). We describe procedures for isolating cells carrying the substitutions and for eliminating the products of secondary off-target events. We demonstrate the technology by integrating a cassette containing a Cu2+-inducible mCherry marker, and we report the expression properties of those lines. When compared with clonal lines made by traditional transformation methods, which lead to the illegitimate insertion of tandem arrays, targeted insertion lines give more uniform expression, lower basal expression, and higher induction ratios. Targeted substitution, though intricate, affords results that should greatly improve comparative expression assays—a major emphasis of cell-based studies.
Asynchronous Multiuser Reception for OFDM in Underwater Acoustic Communications

Recently significant progress has been made on point-to-point underwater acoustic communications, and the interest has grown on the application of those techniques in multiuser communication settings, where the asynchronous nature of multiuser communication poses a grand challenge. This paper develops a time-asynchronous multiuser reception approach for orthogonal frequency-division multiplexing (OFDM) transmissions in underwater acoustic channels. The received data burst is segmented and apportioned to multiple processing units in an overlapped fashion, where the length of the processing unit depends on the maximum asynchronism among users on the OFDM block level. Interference cancellation is adopted to reduce the interblock interference between overlapped processing units. Within each processing unit, the residual inter-block interference from multiple users is aggregated as one external interference which can be parameterized. Multiuser channel estimation, data detection, and interference mitigation are then carried out in an iterative fashion. Simulation and emulated experimental results demonstrate the robustness of the proposed receiver with signal asynchronism among multiple users in both time-invariant and time-varying environments. It is observed that the receiver decoding performance degrades as the channel time variation and the maximum relative delay among users increase.
Crowned dendrimers: pH-responsive pseudorotaxane formation.

With the end goal of incorporating the unique structural and physical properties of dendrimers into supramolecular assemblies, bis(m-phenylene)-32-crown-10-functionalized poly(propyleneimine) dendrimers of the first and third generations have been synthesized and their interaction with paraquat diol has been investigated. Using 1H NMR, we determined that binding to the 4 or 16 crown ether sites occurred in an anti-cooperative fashion, most likely a result of steric influences. Upon protonation of the tertiary amines in the dendritic interior, binding became independent, i.e., statistical, and the average apparent association constant increased by nearly 5-fold; this effect is attributed to rigidification of the dendrimer, which makes its binding sites more accessible and less crowded.
El sentido histórico de algunas transformaciones del arte narrativo

Desde su consolidacion como genero, en el Siglo XVIII, hasta su aparente regeneracion ironica en el Postmodernismo, la novela moderna ha experimentado notables alteraciones estructurales. Algunas de las mas salientes son la reduccion de la figura del narrador autorial, el progresivo abandono de consensuales parametros caracterologicos y morales, la gravitacion del acontecer tematico hacia la esfera de la subjetividad y la creciente eminencia de lo trivial o del detalle perceptual. ?A que se deben estas transformaciones de la matriz narrativa? El presente ensayo sugiere que ellas responden a mutaciones de la conciencia moderna, en especial a la completa inversion del impulso metafisico, bajo el influjo de la imagen cientifica de seres y circunstancias y del anhelo humano de una vision religiosa y redentora. Se indican desarrollos paralelos en la poesia lirica y en la filosofia. From its consolidation as genre in the eighteenth century, to its apparent ironic regeneration in the Post-Modernity, the modern novel has experienced notable structural alterations. Some of the more salient ones are the reduction of the figure of the author-narrator, the progressive abandonment of the character and moral consensus parameters, the gravitation of the thematic occurrence towards the sphere of subjectivity and the growing eminence of the trivial or perceptual detail. To what is owed these transformations of the narrative matrix? This essay suggests that they respond to the mutations of the modern consiousness, especially to the complete inversion of the metaphysical impulse, under the influence of the scientific image of the beings and circumstances and the human yearning for a religious and redeeming vision. Developing parallels are indicated in the lyric poetry and in philosophy.
Electrophilic Diamination of Alkenes by Using FeCl3−PPh3 Complex as the Catalyst

The FeCl(3)-PPh(3) complex was found to effectively catalyze the electrophilic diamination reaction of electron-deficient alkenes. Improvements on yields and stereoselectivity have been achieved for both alpha,beta-unsaturated carboxylic esters and ketones. Under the new catalytic system, alpha,beta-unsaturated carboxylic esters were found to be superior to their ketone counterparts, which is opposite to the previous (C(3)F(7)CO(2))(2)Rh](2)-catalyzed diamination. The reaction employs readily available N,N-dichloro-p-toluenesulfonamide (TsNCl(2)) and acetonitrile as the nitrogen sources and is very easy to perform at room temperature without the special protection of inert gases. The resulting diamino products belong to imidazolidine analogue and can further strengthen the importance of the new reaction. Modest to good yields (52-84%) and high regio- and stereoselectivity have been achieved for 10 examples.
Process dependencies and process interference rules for analyzing the impact of failure in a service composition environment

This paper presents a process dependency model for dynamically analyzing data dependencies among concurrently executing processes in an autonomous, distributed service composition environment. Data dependencies are derived from incremental data changes captured at each service execution site. Deltas are then used within a rule-based recovery model to specify how failure recovery of one process can potentially affect another process execution based on application semantics. This research supports relaxed isolation and application-dependent semantic correctness for concurrent process execution, with a unique approach to resolving the impact of process failure recovery on other processes, using data dependencies derived from distributed, autonomous services.
A unification between nonlinear-nonquadratic optimal control and integrator backstepping

In this paper we develop an optimality-based framework for backstepping controllers. Specifically, using a nonlinear-nonquadratic optimal control framework we develop a family of globally stabilizing backstepping controllers parametrized by the cost functional that is minimized. Furthermore, it is shown that the control Lyapunov function guaranteeing closed-loop stability is a solution to the steady-state Hamilton-Jacobi-Bellman equation for the controlled system and thus guarantees both optimality and stability. The results are specialized to the case of integrator backstepping.