cssi/SciSciGPT-SciSciNet huggingface dataset:
Efficient Computation of Dendritic Microstructures Using Adaptive Mesh Refinement

We study dendritic microstructure evolution using an adaptive grid, finite element method applied to a phase-field model. The computational complexity of our algorithm, per unit time, scales linearly with system size, allowing simulations on very large lattices. We present computations on a ${2}^{17}\ifmmode\times\else\texttimes\fi{}{2}^{17}$ lattice, but note that this is not an upper limit. Time-dependent calculations in two dimensions are in good agreement with the predictions of solvability theory for high undercoolings, but predict higher values of velocity than solvability theory at low undercooling, where transients dominate, in accord with a heuristic criterion which we derive.
New synthetic technologies for the construction of heterocycles and tryptamines.

New synthetic methods for the construction of novel heterocycles and tryptamines are described. Thus, N-Boc anilines (I) are sequentially converted to heterocycles II ((3-(2-aminophenyl)pyrrolidin-3-ol) derivatives), III (substituted 2-oxo-1,2-dihydrospirobenzo[d][1,3]oxazine-4,3′-pyrrolidines), and VI (2-(4,5-dihydro-1H-pyrrol-3-yl)aniline) derivatives through a route involving t-BuLi induced ortho-metalation/LaCl3·2LiCl metal exchange, reaction with N-Boc pyrrolidin-3-one (5), and subsequent decarboxylative fragmentation. Labile intermediates VI are effectively converted to tryptamines Xa and Xb under controlled protic acid conditions. In addition to providing expedient access to the 2-oxo-1,2-dihydrospirobenzo[d][1,3]oxazine-4,3′-pyrrolidines (III), the method is applicable to the synthesis of the corresponding 2-oxo-1,2-dihydrospirobenzo[d][1,3]oxazine-4,3′-piperidine series of spirocycles (e.g., 42) and their precursors (3-(2-aminophenyl)piperidin-3-ol derivatives, e.g., 43) by using N-Boc-protected ...
p-type InN and In-rich InGaN

Capacitance–voltage (CV) measurements using a liquid electrolyte as rectifying contact were used to provide definitive proof of p-type activity beneath a surface inversion layer in Mg-doped InN and In-rich InGaN. Analysis of CV data using the Poisson equation allows net charge as a function of depth to be determined. In undoped InN, good agreement of the net donor concentration below the surface accumulation layer with bulk Hall effect data is obtained. In Mg-doped InN and InGaN, the CV data are shown to be consistent with the presence of a net acceptor concentration NA–ND near 1019 cm–3 below a surface inversion layer. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
The Use of Isotopes in the Study of Reactions of Acyl, Phosphoryl,and Sulfuryl Esters

Acyl, phosphoryl, and sulfuryl transfer reactions involving esters and amides are ubiquitous in the biochemical world, and these reactions are found throughout the biochemical pathways involving proteins, nucleic acids, and other compounds essential for life. Such compounds are also common in commercial chemical processes. The use of isotopes has contributed greatly to our understanding of the chemistry of these compounds. There is an enormous body of literature on the use of isotopes in such studies, and this review does not do justice to this great body of knowledge. We cover a selection of reactions for which multiple experimental applications using isotopes have been used in the advancement of mechanistic studies. Copyright © 2007 John Wiley & Sons, Ltd.
Diastereoselective hydrozirconation of optically active 1-alkenyl boryl derivatives: A conversion of 1-alkynes to optically active 1-deuterio primary alcohols

Abstract Three types of optically pure 1-alkenyl boranes derived from monoterpenes, 1,2-diols and 1,2-amino alcohols were used for the study of diastereoselective hydrozirconation. N-Neopentyl oxazaborolidine derivatives were found to give excellent diastereoselectivity. Optically active 1-deuterio primary alcohols (80–93% ee) were obtained with this new type of asymmetric reaction.
Modeling money demand in large industrial countries: Buffer stock and error correction approaches

The empirical performance of two recent approaches to modeling money demand is compared by estimating functions for narrow and broad aggregates in five large industrial countries. Error correction modeling outperforms the Carr-Darby buffer stock model (which in turn outperforms the conventional partial adjustment model) within the 1974–1985 sample period. Post-sample, however, the comparisons are mixed. The specification of money demand appears to vary substantially from case to case.
A new three-level soft-switched converter

A three-level, constant-frequency, isolated converter which employs a coupled inductor to achieve zero-voltage switching of the primary switches in the entire line and load range is described. Because the coupled inductor does not appear as a series inductance in the load current path, it does not cause a loss of duty cycle or severe voltage ringing across the output rectifiers. The operation and performance of the proposed converter was verified on a 1-kW prototype.
DETECTING KNOT INVERTIBILITY

We discuss the consequences of the possibility that Vassiliev invariants do not detect knot invertibility as well as the fact that quantum Lie group invariants are known not to do so. On the other hand, finite group invariants, such as the set of homomorphisms from the knot group to M11, can detect knot invertibility. For many natural classes of knot invariants, including Vassiliev invariants and quantum Lie group invariants, we can conclude that the invariants either distinguish all oriented knots, or there exist prime, unoriented knots which they do not distinguish.
Effective protection of open space: does planning matter?

High quality plans are considered a crucial part of good land use planning and often used as a proxy measure for success in plan implementation and goal attainment. We explored the relationship of open space plan quality to the implementation of open space plans and attainment of open space protection goals in Research Triangle, North Carolina, USA. To measure plan quality, we used a standard plan evaluation matrix that we modified to focus on open space plans. We evaluated all open space plans in the region that contained a natural resource protection element. To measure plan implementation and open space protection, we developed an online survey and administered it to open space planners charged with implementing the plans. The survey elicited each planner’s perspective on aspects of open space protection in his or her organization. The empirical results (1) indicate that success in implementation and attaining goals are not related to plan quality, (2) highlight the importance of when and how stakeholders are involved in planning and implementation processes, and (3) raise questions about the relationship of planning to implementation. These results suggest that a technically excellent plan does not guarantee the long-term relationships among local landowners, political and appointed officials, and other organizations that are crucial to meeting land protection goals. A greater balance of attention to the entire decision process and building relationships might lead to more success in protecting open space.
Pestalotiopsin A. Side Chain Installation and Exhaustive Probing of Olefin Metathesis as a Possible Tool for Elaborating the Cyclononene Ring

A program directed toward an asymmetric synthesis of pestalotiopsin A is described. The routing begins with the dextrorotatory cyclobutanol 37, which is combined with the enantiomerically defined building blocks ent-15 and 16. These units are incorporated via stereocontrolled 1,2-nucleophilic addition and anti-aldol coupling, respectively. With these straightforward reactions accomplished, the sequel involved the introduction of terminal double bonds in anticipation of the fact that the (E)-cyclononene substructure could be realized by ring-closing metathesis. This central issue was evaluated with several diene substrates and catalysts, all to no avail. Cross-metathesis experiments involving 59 and 65 with the functionalized heptene 60 revealed a marked difference in the inability to engage interaction with the ruthenium catalyst. This awkwardness could not be skirted.
Aldol-cyclization reaction sequence for the synthesis of tetrahydrofurans

Abstract The aldol reactions of α-diazo-β-ketoesters with a variety of aldehydes produced adducts which underwent Rh(II)-catalyzed OH insertion reaction to yield highly substituted tetrahydrofurans. Alkylation and decarboxylation of these tetrahydrofurans formed a wide variety of tetrahydrofuran structures.
The typicality and accessibility of consumer attitudes toward television advertising: : implications for the measurement of attitudes toward advertising in general

Despite the wide array of contemporary advertising formats and media, television advertising remains the most dominant form to which typical consumers are exposed. Research on attitudes toward advertising in general (Att-AiG) implicitly assumes that the Att-AiG measure represents advertising as a whole. A major finding of the current research is that consumers tend to have a mental representation, or exemplar, of the most typical type of advertising—television advertising—when they report their Att-AiG. Therefore, in reality, Att-AiG primarily reflects attitudes toward television advertising. In addition, the results of our experiments indicate that television ad exemplars generate temporal changes in consumers’ reported Att-AiG and attitudes toward television advertising. Theoretical and practical implications are discussed.
Conformational studies on helicenes VII. Synthesis and conformation of 5,6‐dihydrohexahelicene

Irradiation of 2,7-distyrylnaphthalene or 2-styrylbenzo[c]phenanthrene under completely oxygen-free conditions gives rise to the formation of 5,6-dihydrohexahelicene (2) as a consequence of H-shifts in the primary formed cyclization product. The conformation of 2 was analysed by NMR spectroscopy. From the chemical shifts of the aromatic protons, the coupling constants of the saturated moiety and the temperature independence of the spectrum it could be concluded that 2 occurs in one conformation, in which the axial proton at C(5) is directed towards the opposite ring. The resemblance of the spectra of 2 and l-phenylbenzo[c]phenanthrene affirms that this conformation is the less hindered one.
Lattice sigma models with exact supersymmetry

We show how to construct lattice sigma models in one, two and four dimensions which exhibit an exact fermionic symmetry. These models are discretized and twisted versions of conventional supersymmetric sigma models with N = 2 supersymmetry. The fermionic symmetry corresponds to a scalar BRST charge built from the original supercharges. The lattice theories possess local actions and in many cases admit a Wilson term to suppress doubles. In the two and four dimensional theories we show that these lattice theories are invariant under additional discrete symmetries. We argue that the presence of these exact symmetries ensures that no fine tuning is required to achieve N = 2 supersymmetry in the continuum limit. As a concrete example we show preliminary numerical results from a simulation of the O(3) supersymmetric sigma model in two dimensions.
Analysis of triglycerides by capillary gas chromatography with programmed‐temperature injection

The capillary gas chromatographic analysis of complex naturally occurring and food-product triglyceride mixtures is accomplished qualitatively and quantitatively on columns coated with methyl and methyl-phenyl (65%) silicones using programmed-temperature split/splitless and on-column injection. Faster analysis times are achieved using elevated initial column oven temperatures with cold initial injector temperatures.
Dynamic air tasking evaluation in a simulated network-centric battlespace

Joint Air Operations (JAO) are historically designed through centralised planning using static air tasking that assigns air assets to mission packages for the purpose of achieving campaign objectives. The current methodology cannot anticipate changes in the battlespace nor take advantage of real-time information. In this study, we develop a simulation model of the battlespace that utilises a Multi-Criteria Decision Analysis (MCDA) model to assign vehicles to targets by considering four competing objectives (effort, effectiveness, efficiency, and connectivity). A Voronoi network is used to determine the paths of vehicles to their assigned targets and network optimisation is used to validate the quality of the assignments. The results indicate that dynamic air tasking is considerably more effective and more efficient than static air tasking.
Kinetics of NO reduction by CO over supported rhodium catalysts: Isotopic cycling experiments

The catalytic activity of RhAl2O3 and RhCeO2 catalysts was investigated for the reduction of NO by CO under feed-composition cycling conditions as well as under steady feed conditions using a packed-bed reactor and an isotopic reactant, 13CO. Results indicate that the formation of N2O is an important intermediate step during the (CO + NO) reaction over RhAl2O3. The enhanced catalytic activity of RhCeO2 compared with RhAl2O3 under cyclic operating conditions is discussed in light of the oxygen storage capacity of ceria support. The effect of asymmetric cycling is examined in view of the nature of the rate-controlling step which changes with temperature. On the basis of our observations an overall reaction scheme is proposed for the (CO + NO) reaction over RhAl2O3 in which N2O is included as a reaction intermediate.
Projection Volumes of Hyperplane Arrangements

We prove that for any finite real hyperplane arrangement the average projection volumes of the maximal cones are given by the coefficients of the characteristic polynomial of the arrangement. This settles the conjecture of Drton and Klivans that this held for all finite real reflection arrangements. The methods used are geometric and combinatorial. As a consequence, we determine that the angle sums of a zonotope are given by the characteristic polynomial of the order dual of the intersection lattice of the arrangement.
A Fredholm determinant formula for Toeplitz determinants

We prove a formula expressing a generaln byn Toeplitz determinant as a Fredholm determinant of an operator 1 −K acting onl2(n,n+1,...), where the kernelK admits an integral representation in terms of the symbol of the original Toeplitz matrix. The proof is based on the results of one of the authors, see [14], and a formula due to Gessel which expands any Toeplitz determinant into a series of Schur functions. We also consider 3 examples where the kernel involves the Gauss hypergeometric function and its degenerations.
Mobile electronic triaging for emergency response improvement through crowdsourced and sensor-detected information

Emergency resources are often insufficient to satisfy fully the demands for professional help and supplies after a public disaster. Furthermore, in a mass casualty situation, the emphasis shifts from ensuring the best possible outcome for each individual patient to ensuring the best possible outcome for the greatest number of patients. Historically, various manual and electronic medical triage systems have been used both under civil and military conditions to determine the order and priority of emergency treatment, transport, and best possible destination for the patients [3][4][5][6]. Unfortunately, none of those solutions has proven flexible, accurate, scalable or unobtrusive enough to meet the public's expectations [1]. We demonstrate a system for real-time patient assessment which uses mobile electronic triaging accomplished via crowdsourced and sensor-detected information. With the use of our system, emergency management professionals receive most of the information they need for preparing themselves to perform a timely and accurate treatment of their patients even before dispatching a response team to the event. During our demonstration, we will show how our system behaves with different combinations of information inputs and compare its resulting outputs with evaluations done by medical experts. The public will be given the chance to participate in real-time demos by posing as victims and providing self-reported information about their health.
Electronic control of product distribution in the [5+5]-coupling of ortho-alkynylbenzaldehyde derivatives and γ,δ-unsaturated carbene complexes

The coupling of highly oxygenated ortho-alkynylbenzaldehyde derivatives with γ,δ-carbene complexes was evaluated systematically. In all of the electron-rich systems investigated the exclusive product of the reaction is the dihydrophenanthrene derivative. Only the extremely electron-withdrawing methanesulfonate group can prevent this process from occurring. The use of the base additive collidine resulted in a surprising yield enhancement but no other discernable effect on the course of the reaction. Dihydrophenanthrene formation was attributed to rapid dehydration after the opening of a benzo-oxanorbornene intermediate.
Chemistry of Personalized Solar Energy

Personalized energy (PE) is a transformative idea that provides a new modality for the planet’s energy future. By providing solar energy to the individual, an energy supply becomes secure and available to people of both legacy and nonlegacy worlds and minimally contributes to an increase in the anthropogenic level of carbon dioxide. Because PE will be possible only if solar energy is available 24 h a day, 7 days a week, the key enabler for solar PE is an inexpensive storage mechanism. HY (Y = halide or OH−) splitting is a fuel-forming reaction of sufficient energy density for large-scale solar storage, but the reaction relies on chemical transformations that are not understood at the most basic science level. Critical among these are multielectron transfers that are proton-coupled and involve the activation of bonds in energy-poor substrates. The chemistry of these three italicized areas is developed, and from this platform, discovery paths leading to new hydrohalic acid- and water-splitting catalysts are...
The Diamagnetism of Some Organic Binary Mixtures at Different Temperatures

Measurements of the magnetic susceptibilities of mixtures consisting of binary combinations of carbon tetrachloride, benzene and nitrobenzene, made with the improved manometric balance of Wills and Boeker over the range of temperatures from 10\ifmmode^\circ\else\textdegree\fi{}C to 50\ifmmode^\circ\else\textdegree\fi{}C, are described. The results for mixtures of benzene and nitrobenzene, each of which shows no variation of mass susceptibility with temperature, show that the principle of additivity of susceptibilities is valid within the limits of precision of measurement. For mixtures of either benzene or nitrobenzene with carbon tetrachloride, a systematic deviation from additivity is found. The deviations for both groups show a definite dependence upon both concentration and temperature.
Mice lacking FABP9/PERF15 develop sperm head abnormalities but are fertile

The male germ cell-specific fatty acid-binding protein 9 (FABP9/PERF15) is the major component of the murine sperm perforatorium and perinuclear theca. Based on its cytoskeletal association and sequence homology to myelin P2 (FABP8), it has been suggested that FABP9 tethers sperm membranes to the underlying cytoskeleton. Furthermore, its upregulation in apoptotic testicular germ cells and its increased phosphorylation status during capacitation suggested multiple important functions for FABP9. Therefore, we investigated specific functions for FABP9 by means of targeted gene disruption in mice. FABP9(-/-) mice were viable and fertile. Phenotypic analysis showed that FABP9(-/-) mice had significant increases in sperm head abnormalities (~8% greater than their WT cohorts); in particular, we observed the reduction or absence of the characteristic structural element known as the "ventral spur" in ~10% of FABP9(-/-) sperm. However, deficiency of FABP9 affected neither membrane tethering to the perinuclear theca nor the fatty acid composition of sperm. Moreover, epididymal sperm numbers were not affected in FABP9(-/-) mice. Therefore, we conclude that FABP9 plays only a minor role in providing the murine sperm head its characteristic shape and is not absolutely required for spermatogenesis or sperm function.
Expansions of GMM statistics that indicate their properties under weak and/or many instruments and the bootstrap

We show that the sensitivity of the limit distribution of commonly used GMM statistics to weak and many instruments results from superfluous elements in the higher order expansion of these statistics. When the instruments are strong and their number is small, these elements are of higher order and result in higher order biases. When instruments are weak and/or their number is large, they are, however, of zero-th order and influence the limit distributions of GMM statistics. Edgeworth approximations do not remove these superfluous elements. Expansions of GMM statistics that are robust to weak or many instruments do not possess these superfluous elements. Their robustness is therefore the result of improved higher order properties. This renders an additional reason for usage of these statistics. An Edgeworth expansion of the robust statistics can be constructed so the approximation of their finite sample distribution can be further improved upon by use of the bootstrap. We illustrate the finite sample performance of GMM statistics by constructing power curves for tests on the autocorrelation parameter in a panel autoregressive model using both asymptotic and bootstrap critical values.
User applications driven by the community contribution framework MPContribs in the Materials Project

This work discusses how the MPContribs framework in the Materials Project MP allows user-contributed data to be shown and analyzed alongside the core MP database. The MP is a searchable database of electronic structure properties of over 65,000 bulk solid materials, which is accessible through a web-based science-gateway. We describe the motivation for enabling user contributions to the materials data and present the framework's features and challenges in the context of two real applications. These use cases illustrate how scientific collaborations can build applications with their own 'user-contributed' data using MPContribs. The Nanoporous Materials Explorer application provides a unique search interface to a novel dataset of hundreds of thousands of materials, each with tables of user-contributed values related to material adsorption and density at varying temperature and pressure. The Unified Theoretical and Experimental X-ray Spectroscopy application discusses a full workflow for the association, dissemination, and combined analyses of experimental data from the Advanced Light Source with MP's theoretical core data, using MPContribs tools for data formatting, management, and exploration. The capabilities being developed for these collaborations are serving as the model for how new materials data can be incorporated into the MP website with minimal staff overhead while giving powerful tools for data search and display to the user community. Copyright © 2015 John Wiley & Sons, Ltd.
Preserving the lepton asymmetry in the brane world

In models where the Standard Model spectrum is localized on a brane embedded in a higher-dimensional spacetime, we discuss the lepton number violation induced by the emission of right-handed neutrinos from the brane. We show that the presence of the right-handed neutrinos in the bulk may lead to rapid lepton number violating processes which above the electroweak scale would wash away any prior lepton or baryon asymmetry. We derive constraints on the Yukawa couplings of these states in order to preserve the lepton asymmetry. We show that this has a natural interpretation in the brane world.
A cooperative N-heterocyclic carbene/chiral phosphate catalysis system for allenolate annulations.

The highly enantioselective NHC-catalyzed [3+2] annulation reaction with α,β-alkynals and α-ketoesters has been developed. A new mode of cooperative catalysis involving the combination of a chiral Bronsted acid and a C1-symmetric biaryl saturated-imidazolium precatalyst was required to generate the desired γ-crotonolactones in high yields and levels of enantioselectivity.
A geometric analysis of Renegar’s condition number, and its interplay with conic curvature

For a conic linear system of the form Ax ∈K, K a convex cone, several condition measures have been extensively studied in the last dozen years. Among these, Renegar’s condition number $${\mathcal{C}}(A)$$is arguably the most prominent for its relation to data perturbation, error bounds, problem geometry, and computational complexity of algorithms. Nonetheless, $${\mathcal{C}}(A)$$is a representation-dependent measure which is usually difficult to interpret and may lead to overly conservative bounds of computational complexity and/or geometric quantities associated with the set of feasible solutions. Herein we show that Renegar’s condition number is bounded from above and below by certain purely geometric quantities associated with A and K; furthermore our bounds highlight the role of the singular values of A and their relationship with the condition number. Moreover, by using the notion of conic curvature, we show how Renegar’s condition number can be used to provide both lower and upper bounds on the width of the set of feasible solutions. This complements the literature where only lower bounds have heretofore been developed.
Simulation of human problem-solving

Simulating human problem-solving on a digital computer looks deceptively simple. All one must do is program computers to solve problems in such a manner that the computer employs the identical strategies and tactics that humans do. This will probably prove to be as simple in theory and as hard in actual practice as was the development of reliable digital computers. One of the purposes of this paper is to describe a few of the pitfalls that seem to lie in the path of anyone trying to program machines to "think."
Knowing a winning business idea when you see one

Identifying which business ideas have real commercial potential is fraught with uncertainty, and even the most admired companies have stumbled. It's not as if they don't know what the challenges of innovation are. A new product has to offer customers exceptional utility at an attractive price, and the company must be able to deliver it at a tidy profit. But the uncertainties surrounding innovation are so great that even the most insightful managers have a hard time evaluating the commercial readiness of new business ideas. In this article, W. Chan Kim and Renee Mauborgne introduce three tools that managers can use to help strip away some of that uncertainty. The first tool, "the buyer utility map," indicates how likely it is that customers will be attracted to a new business idea. The second, "the price corridor of the mass," identifies what price will unlock the greatest number of customers. And the third tool, "the business model guide," offers a framework for figuring out whether and how a company can profitably deliver the new idea at the targeted price. Applying the tools, though, is not the end of the story. Many innovations have to overcome adoption hurdles--strong resistance from stakeholders inside and outside the company. Often overlooked in the planning process, adoption hurdles can make or break the commercial viability of even the most powerful new ideas. The authors conclude by discussing how managers can head off negative reactions from stakeholders.
Infusing the Interdisciplinary into Medical/ Health Sciences Education: Vitamins or Vaccines?

Academic medical institutions have responded to recent changes and challenges confronting the health care system with various recommendations for curricular reform; many grouped under the rubric of interdisciplinary training. The ultimate goal is to create physicians, with mastery over specialized knowledge, who can practice cost-effective, humanized medicine. This article elaborates a conceptual classification system that categorizes curricular reform recommendations into one of two approaches ? Vitamins or Vaccines ? that highlights differences in the processes of curricular reform programs. Programs seeking the same goal may create different types of practitioners depending on the approach dominating the professional training and socialization process. The Vitamins approach is reactive, supplemental, and incremental, often imparting instruction instead of education. The Vaccines approach is proactive, addresses fundamental factors, and seeks long-term solutions from a preventive perspective. As educators, our choice of approach, Vitamins or Vaccines, for curricular reform will determine how academia prepares physicians for the future.
NN correlations measured in 3He(e, e'pp)n

We have measured the 3He (e, e'pp)n reaction in the Jefferson Lab CLAS with 2.2 and 4.4 GeV electrons. We looked at the energy distribution of events with all three nucleons at high momentum (p > 250 MeV/c). This distribution has peaks where two nucleons each have 20% or less of the energy transfer (i.e., the third or ?leading? nucleon carries most of the kinetic energy). The angular distribution of these two ?fast? nucleons shows a very large back-to-back peak, indicating the effect of correlations. While there is some theoretical disagreement, experimental evidence, plus calculations at lower energy by W. Glockle, indicates that these events are primarily sensitive to NN correlations.
Cournot Oligopoly With Uncertain Entry

The study of oligopoly has progressed along two lines. The first deals with the behaviour of a firm viewing existing rivals as responsive to its actions. The critical assumption in this analysis is the firm's conjecture about rivals' reactions to its price or quantity decisions. Cournot [4] provided the classic supposition that rivals will maintain their current level of output in response to a change in the given firm's output level. This implies price matching by rivals. Questions addressed include those of existence and stability of equilibrium in an oligopolistic market, its possible convergence to the competitive solution as the number of firms increases indefinitely, and whether the approach is monotone (quasi-competitiveness). A recent synthesis is provided by Ruffin [11]. The second strand of inquiry focuses on the firm's behaviour regarding potential rivals, especially actions designed to preserve positive profits. The strategy of pricing to retard or preclude entry, " limit pricing ", has received the most intense study. A summary of earlier theoretical developments is provided by Bhagwati [2]; more recent contributions include Gaskins [6], Pyatt [10], Baron [1], and Kamien and Schwartz [8, 9]. The first of these two lines of inquiry, focused on interaction among existing rivals, may be viewed as a short-run theory of oligopoly. The second approach, with its attention to consequences of potential rivalry, forms the complementary long-run theory. This paper constitutes an attempt to bridge these parallel developments, an objective shared with Fisher [5]. In the next section we present a model of a firm thatviews its existingrivals in accordance with the classic Cournot assumption and views potential rivals in the manner posited in our paper [8]. The timing of rival entry is regarded as a random variable whose probability distribution is dependent on current industry price. After obtaining necessary conditions for maximization of the firm's long-run expected profits, we extend the first four theorems of Ruffin's paper to the case in which potential rivalry is recognized. The classic Cournot oligopoly model is compared with the present one and our results are summarized. 2. THE MODEL
The use of C-band satellites for low cost, low data rate mobile applications

Based on experience in Desert Storm and other armed conflicts, the use of commercial SATCOM to support Department of Defense (DoD) communications is crucial to an operation's success. But, the use of commercial SATCOM to support low data rate (less than 64 Kbps) mobile or remote communication has been minimal, if nonexistent. Current commercial systems require large, narrow beam, antennas to prevent the interference inherent in the closely spaced commercial satellites (as little as 2/spl deg/ apart). This has limited these systems to large fixed site applications. This paper describes the use of simple signal processing techniques to support the use of broadbeam C-band antennas on small, low cost terminals. The proposed use of C-band systems with small broadbeam antennas opens up C-band satellites and technology to a whole new class of low data rate, mobile commercial and military applications not previously considered. >
Frank Snodgrass 1920–1985

Frank Snodgrass died this morning on his farm in Oregon. He had been my partner for 23 years prior to his retirement in 1976. So many oceanographic techniques that are taken for granted today were introduced by Frank. He pioneered digital recording. He was the first (in 1965) to drop gear in freefall to the sea floor for subsequent acoustic recall. I believe that he was the first to use a portable sea-going laboratory. We still use the frame of Frank's first model, which dates back over 20 years.
Tanzania's Infrastructure: A Continental Perspective

Infrastructure contributed 1.3 percentage points to Tanzania's annual per capital GDP growth during the 2000s. If the country's infrastructure endowment were improved to the level of the African leader, Mauritius, annual per capita growth rates could increase by 3.4 percent. Tanzania has made great progress in reforming its trunk roads, improving the quality of the road network. The country has also seen significant gains in ICT networks, and has one of the most competitive domestic air transport sectors in Africa. The power sector poses Tanzania's most serious infrastructure challenge. Despite significant improvements in pricing and operational performance in recent years, inefficiency still absorbs about 1.4 percent of GDP. Moreover, due to heavy reliance on hydro-power the sector remains vulnerable to climate variability. The port of Dar es Salaam also suffers from performance problems as rapid traffic growth has increasingly exposed deficiencies in storage and access to the port. Poor access to safe water is another challenge, exacerbated by poor budget execution in the sector. Tanzania would need to invest $2.4 billion annually for 10 years to meet its infrastructure targets. Spending at that level would absorb just over 20 percent of the country's GDP. Existing spending stands at $1.2 billion a year. Tanzania loses $0.5 billion each year to inefficiencies such as underpricing, undercollection of revenue, overstaffing, and lack of budget prioritization. But even if inefficiencies could be fully captured, an annual funding gap of $0.7 billion would remain. That gap could be shrunk to $0.4 billion if lower-cost technologies were adopted and if regional power trade could be further developed.
A user study of the expandable grid applied to P3P privacy policy visualization

Displaying website privacy policies to consumers in ways they understand is an important part of gaining consumers' trust and informed consent, yet most website privacy policies today are presented in confusing, legalistic natural language. Moreover, because website privacy policy presentations vary from website to website, policies are difficult to compare and it is difficult for consumers to determine which websites offer the best privacy protections. The Platform for Privacy Preferences P3P) addresses part of the problem with natural language policies by providing a formal, machine-readable language for expressing privacy policies in a manner that is standardized across websites. To address remaining problems, an automated tool must be developed to read P3P policies and display them to users in a comprehensible way. To this end, we have developed a P3P policy presentation tool based on the Expandable Grid, a visualization technique for displaying policies in an interactive matrix. In prior work, the Expandable Grid has been shown to work well for displaying file permissions policies, so it appears to hold promise for presenting online privacy policies as well. To evaluate our Expandable Grid interface, we conducted two user studies, an online study with 520 participants and a laboratory study with 12 participants. The studies compared participants' comprehension of privacy policies presented with the Grid interface with their comprehension of the same policies presented in natural language. To our surprise, comprehension of policies was, for the most part, no better with the Grid interface than with natural language. We describe why the Grid interface did not perform well in our study and discuss implications for when and how the Expandable Grid concept can be usefully applied.
Transcription Termination and 3′-End Processing of the Spliced Leader RNA in Kinetoplastids

Addition of a 39-nucleotide (nt) spliced leader (SL) by trans splicing is a basic requirement for all trypanosome nuclear mRNAs. The SL RNA in Leishmania tarentolae is a 96-nt precursor transcript synthesized by a polymerase that resembles polymerase II most closely. To analyze SL RNA genesis, we mutated SL RNA intron structures and sequence elements: stem-loops II and III, the Sm-binding site, and the downstream T tract. Using an exon-tagged SL RNA gene, we examined the phenotypes produced by a second-site 10-bp linker scan mutagenic series and directed mutagenesis. Here we report that transcription is terminated by the T tract, which is common to the 3′ end of all kinetoplastid SL RNA genes, and that more than six T’s are required for efficient termination in vivo. We describe mutants whose SL RNAs end in the T tract or appear to lack efficient termination but can generate wild-type 3′ ends. Transcriptionally active nuclear extracts show staggered products in the T tract, directed by eight or more T’s. The in vivo and in vitro data suggest that SL RNA transcription termination is staggered in the T tract and is followed by nucleolytic processing to generate the mature 3′ end. We show that the Sm-binding site and stem-loop III structures are necessary for correct 3′-end formation. Thus, we have defined the transcription termination element for the SL RNA gene. The termination mechanism differs from that of vertebrate small nuclear RNA genes and the SL RNA homologue in Ascaris.
Women, Water, and Development

That women play a central role in the provision, management, and safeguarding of water is one of the four internationally accepted principles of water management. This principle is especially important for the developing world where millions of women lack access to water for their basic needs. The objectives of this chapter are to summarize what is known about women with respect to water and about water with respect to women as well as to provide a sense of the current debates around these themes. A review of the literature suggests that the lack of gender-disaggregated data on the impacts of water policies, and underlying disagreements on how gender and development should be theorized, makes it difficult to reach robust conclusions on which policies can best assure poor women reliable access to water for their lives and livelihoods.
A Single Circumbinary Disk in the HD 98800 Quadruple System

We present subarcsecond thermal infrared imaging of HD 98800, a young quadruple system composed of a pair of low-mass spectroscopic binaries separated by 0f8 (38 AU), each with a K-dwarf primary. Images at wavelengths ranging from 5 to 24.5 µm show unequivocally that the optically fainter binary, HD 98800B, is the sole source of a comparatively large infrared excess on which a silicate emission feature is superposed. The excess is detected only at wavelengths of 7.9 µm and longer, peaks at 25 µm, and has a best-fit blackbody temperature of 150 K, indicating that most of the dust lies at distances greater than the orbital separation of the spectroscopic binary. We estimate the radial extent of the dust with a disk model that approximates radiation from the spectroscopic binary as a single source of equivalent luminosity. Given the data, the most likely values of disk properties in the ranges considered are Rin=5.0+/-2.5 AU, DeltaR=13+/-8 AU, lambda0=2+4-1.5 µm, gamma=0+/-2.5, and sigmatotal=16+/-3 AU2, where Rin is the inner radius, DeltaR is the radial extent of the disk, lambda0 is the effective grain size, gamma is the radial power-law exponent of the optical depth tau, and sigmatotal is the total cross section of the grains. The range of implied disk masses is 0.001-0.1 times that of the Moon. These results show that, for a wide range of possible disk properties, a circumbinary disk is far more likely than a narrow ring.
Employee spinoffs and other entrants: Stylized facts from Brazil

Using a comprehensive linked employer-employee database from Brazil for the period 1995-2001, we are able for the first time to compare firms founded as employee spinoffs to new firms without parents and to diversification ventures of existing firms entering a new industry. Employee spinoffs are defined either as the director/manager having moved from a parent in the same industry or as one-quarter of the employees having shifted from a common parent. Depending on definition, employee spinoffs account for between one-sixth and one-third of the new firms in Brazil’s private sector during this period. Regardless of definition, size at entry is larger for employee spinoffs than for new firms without parents but smaller than for diversification ventures of existing firms. Similarly, exit rates for employee spinoffs are less than for new firms without parents and comparable to those for diversification ventures of existing firms. These results suggest that we can think of some part of a firm’s productivity draw in the Jovanovic (1982) model as embodied in the firm’s employees and portable by them to a new firm.
The Effects of Avatar: Based Customization on Player Identification

Games allow players to perceive themselves in alternate ways in imagined worlds. Player identification is one of the outcomes of gameplay experiences in these worlds and has been shown to affect enjoyment and reduce self-discrepancy. Avatar-based customization has potential to impact player identification by shaping the relationship between the player and the character. This mixed method study aims to fill the gap in the identification literature by examining the effects of avatar-based customization on players' identification with and empathy towards their characters in a massively multiplayer online game, Lord of the Rings Online (LotRO). Participants (N = 66) played LotRO either in customization or in no-customization groups for about ten hours in four sessions over two weeks in a controlled lab setting. Data were collected through interviews, surveys and observations. Results showed both time and avatar-based customization positively impacted players' identification with their avatars. Self-Determination Theory is used to interpret results.
THE METALLICITY OF THE CM DRACONIS SYSTEM

The CM Draconis system comprises two eclipsing mid-M dwarfs of nearly equal mass in a 1.27?day orbit. This well-studied eclipsing binary has often been used for benchmark tests of stellar models, since its components are among the lowest mass stars with well-measured masses and radii ( 1% relative precision). However, as with many other low-mass stars, non-magnetic models have been unable to match the observed radii and effective temperatures for CM Dra at the 5%-10% level. To date, the uncertain metallicity of the system has complicated comparison of theoretical isochrones with observations. In this Letter, we use data from the SpeX instrument on the NASA Infrared Telescope Facility to measure the metallicity of the system during primary and secondary eclipses, as well as out of eclipse, based on an empirical metallicity calibration in the H and K near-infrared (NIR) bands. We derive an [Fe/H] = -0.30 ? 0.12 that is consistent across all orbital phases. The determination of [Fe/H] for this system constrains a key dimension of parameter space when attempting to reconcile model isochrone predictions and observations.
Methodology for Probabilistic Life Prediction of Multiple-Anomaly Materials

Titanium gas-turbine engine components may contain anomalies that are not representative of nominal conditions. If undetected, they can lead to uncontained failure of the engine and associated loss of life. A probabilistic framework has been developed to predict the risk of fracture associated with titanium rotors and disks containing rare material anomalies. A recent Federal Aviation Administration Advisory Circular also provides guidance for the design of these components. However, some materials may exhibit relatively higher anomaly occurrence rates compared to those found in titanium alloys. In addition, the crack formation life for these materials may be nonnegligible and must be considered in the risk computation. When these materials are used, a single disk could contain a number of anomalies with unequal crack formation periods, and so the existing probabilistic framework is no longer valid. A methodology is presented for probabilistic life prediction of components with relatively large numbers of material anomalies. It is an extension of the probabilistic framework originally developed for titanium materials with hard alpha anomalies. The methodology is presented and illustrated for an aircraft gas-turbine engine disk. The results can be applied to fracture-mechanics-based probabilistic life prediction of alloys with large numbers of material anomalies.
Wavelength Scaling and Square/Stripe and Grain Mobility Transitions in Vertically Oscillated Granular Layers

Abstract Laboratory experiments are conducted to examine granular wave patterns near onset as a function of the container oscillation frequency f and amplitude A, layer depth H, and grain diameter D. The primary transition from a flat grain layer to standing waves occurs when the layer remains dilated after making contact with the container. With a flat layer and increasing dimensionless peak container acceleration Γ=4 π 2 f 2 A/g (g is the acceleration due to gravity), the wave transition occurs for Γ ≈2.6, but with decreasing Γ the waves persist to Γ =2.2. For 2.2 Γ f f ss and stripes for f > f ss ; H determines the square/stripe transition frequency f ss =0.33 g/H . The dispersion relations for layers with varying H collapse onto the curve λ/H=1.0+1.1(f H/g ) −1.32±0.03 when the peak container velocity v=2π Af exceeds a critical value, v gm ≈3 Dg . Local collision pressure measurements suggest that v gm is associated with a transition in the horizontal g rain m obility: for v>v gm , there is a hydrodynamic-like horizontal sloshing motion, while for v gm , the grains are essentially immobile and the stripe pattern apparently arises from a bending of the granular layer. For f at v gm less than f ss and v gm , patterns are tenuous and disordered.
Paediatric anaesthesia: a risky business?

The definition of risk is "the chance or possibility of danger, loss or injury". Assessing risk in paediatric anaesthesia depends on the angle from which the problem is approached: the patients and their parents, doctors, hospital managers, policy makers or insurance companies. For the child (the patient), the risks involve a variety of factors, including the medication choices that the anaesthetist makes, the potential for neurodegeneration (high on the risk list for neonates and infants), whether the anaesthetist is satisfactorily qualified and experienced to provide adequate perioperative care so that the infant wakes up safely, and monitoring of the operation in accordance with local and international safety standards of care.