cssi/SciSciGPT-SciSciNet huggingface dataset:
Analgesics, Allergy and Asthma

Intolerance to analgesics is common in patients with bronchial asthma, nasal polyps and urticaria. Symptoms of intolerance resemble those of allergy, but the events precipitating them can rarely be traced to reactions between the drug and a specific antibody or sensitised T-lymphocytes. In 8 to 20% of adult asthmatics, aspirin and several other analgesics provoke asthmatic attacks, probably through inhibition of cyclo-oxygenase. This is a distinct and important clinical syndrome with a specific history, course and clinial presentation and a number of unique peculiarities which still require elucidation at the biochemical level. Up to 40% of patients with chronic urticaria develop an obvious increase in weals and swelling after taking aspirin. These reactions occur only when urticaria is active, and though the reason for them is not known, it appears that different mechanisms may be responsible in different patients. Skin reactions other than exacerbation of chronic urticaria are less common, but may create serious clinical problems. The clinical background of a patient often determines the type of adverse response to an analgesic. Thus, in certain individuals, analgesics can produce anaphylactic reactions and/or urticaria, probably through an immunological mechanism, while in some asthmatics they precipitate bronchoconstriction, probably through inhibition of bronchial cyclo-oxygenase. Study of untoward reactions to analgesics not only leads to safer pharmacotherapy, but it also offers a fascinating model for better understanding of some diseases.
Satellite-mounted robot manipulators- new kinematics and reaction moment compensation

Cas d'un robot manipulateur monte sur un satellite. Etude cinematique et compensation des moments de reaction
Staring at the sun: Overcoming the terror of death.

In this article, the author, an eminent psychiatrist, psychotherapist, and writer, presents a brief introduction to the problem of human mortality as one of the givens of human existence, locating the problem squarely in the domain of self- awareness or human consciousness. He names the problem as death anxiety, a fear that can erupt into terror depriving an individual of happiness and fulfillment. Having identified the problem of death anxiety, the author then goes on, through a personal memoir, to disclose his personal ideas about death, their autobiographical sources, and how they have affected his life, as well as his coming to terms with the necessity of his own death. Within this autobiographical essay, he touches on experiences of death and dying from his youth, adolescence, and adulthood as well as his experience of the death of three of his most prized mentors: Jerome Frank, John Whitehorn, and Rollo May.
The Baring Crisis in a Mexican Mirror

Conventional wisdom has it that the Mexican crisis of 1994-95 was the first financial crisis of the 21st century. In this paper I argue that it may be better understood as the last financial crisis of the 19th. The crisis in Mexico exhibits striking similarities to the Baring Crisis of 1890, an event that did much to shape modern opinion about the causes and consequences of financial crises and the role for official management.
Viscous evolution of accretion discs in the quiescence of dwarf novae

The viscous evolution of accretion discs in the quiescence of dwarf novae is investigated semi-analytically. There are two key factors: the inward flow of the initial mass in the disc and the diffusion of the material added into the disc later. The results are compared with the brightness temperature distributions obtained by the eclipse mapping of OY Car and Z Cha.
Regulatory Competition Among Accounting Standards Within And Across International Boundaries

Most financial reporting jurisdictions across the world allow a local monopoly in financial reporting standards for publicly held corporations. In the United States, for example, the statutory authority over these standards is vested in the Securities and Exchange Commission, who delegates the task of writing standards to the Financial Accounting Standards Board, retaining an oversight function for itself. In some countries these standards are specified through statutes in varying levels of detail. Few countries permit their corporations to choose among two or more sets of competing standards; monopoly is the reigning norm. This paper examines regulatory competition as a model for writing and implementing corporate financial standards. Under this model, two or more approved standardsetting bodies are allowed to compete for the allegiance of the reporting entities. Each corporation can choose which of the two or more sets of competing standards it wishes to use in preparing its financial reports. Corporations must choose an entire set of standards in toto, clearly mark the reports with the set of standards used to prepare them, and pay a fee to the body who wrote the standards. We examine the consequences of such regulatory competition for the quality and efficiency of standards, quality of information provided to shareholders and other interested parties, and the efficiency of corporate governance and managerial actions. A debate on the merits of monopoly
A lack of toll-like receptor 4 expression variability in the immediate preoperative period: a pilot study of elective surgical patients.

Toll-like receptor 4 (TLR-4), a receptor of innate immunity, provides the site for the lipopolysaccharide shell of Gram-negative organisms to bind and initiate the inflammatory cascade in sepsis. Its expression has been studied in various disease states (sepsis, asthma, atherosclerosis, immunodeficiencies), ethnic groups (Chinese, Irish, Scottish, Gambian), ages, level of physical training, gestational status, and trauma. The expanding body of evidence in regard to TLR signaling is demonstrating the importance between such signaling and human disease. A translational research project between the Departments of Anesthesiology and Medical Microbiology and Immunology was initiated to determine any difference in the amount of TLR-4 expression in elective preoperative patients in regard to height, weight, age, sex, and body surface area (BSA), body mass index (BMI), hypertension, and diabetes. Race was not analyzed. After institutional research board approval, a prospective study of the blood specimens of 52 consecutive, elective, preoperative patients was performed. The blood was directly decanted into a PAXgene Blood RNA tube (Qiagen) designed for the stabilization of RNA from whole blood. Whole blood RNA was extracted using the PAXgeneTM Blood RNA System (PreAnalytiX, Hombrechitikon, Switzerland), including treatment with DNase I to prevent genomic DNA contamination. Quantification of TLR-4 expression levels in human lymphocytes was by RT-PCR and results compared with standard curves. Pearsons's correlation coefficient was use for statistical analysis of the continuous variables and t-testing was used in the analysis of the categorical variables. The TLR-4 concentration varied from 0.211 to 2.490 fmol/μ l per cDNA; however, there was no statistical significance between the concentration of TLR-4/cDNA expressed by RT-PCR and the continuous variables (height, weight, BMI, BSA, and age) nor the categorical variables (hypertension, diabetes, and sex) (Table ​(Table1).1). None of the patients had postoperative infections. This was an initial attempt to quantify the TLR-4 receptor expression by elective patient variable preoperatively. It provided an opportunity for anesthesiologists to take their practice to the laboratory to explore the immunologic basis of their actions. Table 1
Detection of interstellar rotationally excited CH

Rotationally-excited CH has been detected for the first time in the ISM. The first excited level (F1, N=1, J=3/2) was observed via its ʌ-doubling transition at 700 MHz towards W 51—the lowest frequency molecular lines detected to date. The two main hyperfine components were seen in absorption, with approximately optically-thin, LTE intensities. The spectra qualitatively resemble the masering line profiles of the ground state at the same position, suggesting both transitions orginate in the same gas. Column density derived for the excited state is NL>1.2-1.4 x 10144 cm-2, comparable to that of the ground state in W 51 and most other sources. The large excited state population cannot easily be explained by FARIR radiative dust excitation; collisions with gas densities n(H2)>106 cm-3 are probably the dominant source of excitation. CH is therefore present with considerable abundance at very high densitites in W 51, contrary to predictions of chemical models. The F1, N=1, J=3/2 measurements are consistent with the Gwinn-Townes model for collisional pumping of the ground state maser, but are not conclusive evidence for it.
Cosmological calculations on the GPU

Abstract Cosmological measurements require the calculation of nontrivial quantities over large datasets. The next generation of survey telescopes will yield measurements of billions of galaxies. The scale of these datasets, and the nature of the calculations involved, make cosmological calculations ideal models for implementation on graphics processing units (GPUs). We consider two cosmological calculations, the two-point angular correlation function and the aperture mass statistic, and aim to improve the calculation time by constructing code for calculating them on the GPU. Using CUDA, we implement the two algorithms on the GPU and compare the calculation speeds to comparable code run on the CPU. We obtain a code speed-up of between 10 and 180 × faster, compared to performing the same calculation on the CPU. The code has been made publicly available. GPUs are a useful tool for cosmological calculations, even for datasets the size of current surveys, allowing calculations to be made one or two orders of magnitude faster.
On the constant in Burgess' bound for the number of consecutive residues or non-residues

We give an explicit version of a result due to D. Burgess. Let be a non-principal Dirichlet character modulo a prime p. We show that the maximum number of consecutive integers for which takes on a particular value is less than
Enforcing spatial constraints for mobile RBAC systems

Proposed models for spatially-aware extensions of role-based access control (RBAC) combine the administrative and security advantages of RBAC with the dynamic nature of mobile and pervasive computing systems. However, implementing systems that enforce these models poses a number of challenges. As a solution, we propose an architecture for designing such a system. The architecture is based on an enhanced RBAC model that supports location-based access control policies by incorporating spatial constraints.Enforcing spatially-aware RBAC policies in a mobile environment requires addressing several challenges. First, one must guarantee the integrity of a user's location during an access request. We adopt a proximity-based solution using Near-Field Communication (NFC) technology. The next challenge is to verify the user's position continuously satisfies the location constraints. To capture these policy restrictions, we incorporate elements of the UCON_ABC usage control model in our architecture. In this work, we also propose a number of protocols, describe our prototype implementation, report the performance of our prototype, and evaluate the security guarantees.
Electrical imaging of engineered hydraulic barriers

Electrical resistance tomography (ERT) was used to image the full-scale test emplacement of a thin-wall grout barrier installed by high-pressure jetting and a thick-wall polymer barrier installed by low-pressure permeation injection. Both case studies compared images of electrical resistivity before and after barrier installation. Barrier materials were imaged as anomalies which were more electrically conducting than the native sandy soils at the test sites. Although the spatial resolution of the ERT was insufficient to resolve flaws smaller than a reconstruction voxel (50 cm on a side), the images did show the spatial extent of the barrier materials and therefore the general shape of the structures. To verify barrier performance, ERT was also used to monitor a flood test of a thin-wall grout barrier. Electrical resistivity changes were imaged as a saltwater tracer moved through the barrier at locations which were later found to be defects in a wall or the joining of two walls.
When Does Decisional Impairment Become Decisional Incompetence? Ethical and Methodological Issues in Capacity Research in Schizophrenia

Most decision-making capacity (DMC) research has focused on measuring the decision-making abilities of patients, rather than on how such persons may be categorized as competent or incompetent. However, research ethics policies and practices either assume that we can differentiate or attempt to guide the differentiation of the competent from the incompetent. Thus there is a need to build on the recent advances in capacity research by conceptualizing and studying DMC as a categorical concept. This review discusses why there is a need for such research and addresses challenges and obstacles, both practical and theoretical. After a discussion of the potential obstacles and suggesting ways to overcome them, it discusses why clinicians with expertise in capacity assessments may be the best source of a provisional "gold standard" for criterion validation of categorical capacity status. The review provides discussions of selected key methodological issues in conducting research that treats DMC as a categorical concept, such as the issue of the optimal number of expert judges needed to generate a criterion standard and the kinds of information presented to the experts in obtaining their judgments. Future research needs are outlined.
An Interfacial Tracking Method for Ultrashort Pulse Laser Melting and Resolidification of a Thin Metal Film

An interfacial tracking method was developed to model rapid melting and resolidification of a freestanding metal film subject to an ultrashort laser pulse. The laser energy was deposited to the electrons near thin film surface, and subsequently diffused into a deeper part of the electron gas and transferred to the lattice. The energy equations for the electron and lattice were coupled through an electron-lattice coupling factor. Melting and resolidification were modeled by considering the interfacial energy balance and nucleation dynamics. An iterative solution procedure was employed to determine the elevated melting temperature and depressed solidification temperature in the ultrafast phase-change processes. The predicted surface lattice temperature, interfacial location, interfacial temperature, and interfacial velocity were compared with those obtained by an explicit enthalpy model. The effects of the electron thermal conductivity models, ballistic range, and laser fluence on the melting and resolidification were also investigated.
ECONOMIC TRANSFORMATION AND ITS POLITICAL DISCONTENTS IN CHINA: Authoritarianism, Unequal Growth, and the Dilemmas of Political Development

▪ Abstract China's economic growth and transition pose fascinating questions for social scientists. In the economic realm, proponents of the market-preserving federalism (MPF) model appear to have gone too far. In reality, China's central leadership has retained the prerogative to appoint top provincial officials as well as the power to reconfigure central-provincial fiscal relations, thus defying predictions of the MPF model. In the social realm, rapid growth has propelled the expansion of the middle class, but the large increase in inequality has sharpened social cleavages and class conflicts. The uncertainties of market transition and rising social conflicts pose major challenges for the ruling elite and for China's political development.
An Expeditious Total Synthesis of (±)-Stenine

(±)-Stenine was synthesized in eight steps from a known ketophosphonate reagent. The key step was an exo-selective Diels−Alder/intramolecular Schmidt domino reaction that afforded three of the four rings and four stereocenters in a single reaction.
Gender and Public Access Computing: An International Perspective

Information and Communication Technologies (ICTs), and public access to computers with Internet connectivity in particular, can assist community development efforts and help bridge the so-called digital divide. However, use of ICT is not gender neutral. Technical, social, and cultural barriers emphasize women's exclusion from the benefits of ICT for development. This paper offers a qualitative analysis of the benefits of ICT and the barriers facing women to fully realize those benefits, particularly through public access to computers and Internet in libraries, telecenters, and cybercafes. Individual benefits include increased self-esteem, reduced isolation, access to markets, empowerment, and access to health information. Collective benefits include economic growth, improved health and education, capacity building, and cultural transformation. Barriers that are particularly significant to women are location, infrastructure, and connectivity; time and money; lack of relevant content; low education and literacy; and social norms and perceptions. This paper draws from publicly available reports of a larger study of public access venues in 25 developing countries around the world.
Land use regulation with durable capital

This article compares the level and distribution of the welfare changes from restricting land available for residential development in a city. We compare the economic costs when residential capital is durable with the costs when capital is perfectly malleable and those when population is also freely mobile. Our simulation, based on the stylized specification of an urban location model, suggests that in a more realistic setting with durable capital, the costs of regulation are substantially higher than they are when capital is assumed to be malleable or when households are assumed to be fully mobile. Importantly, the extent of wealth redistribution attributable to these regulations is much larger when these more realistic factors are recognized. When capital is durable, the results also imply that far more new development takes place on previously undeveloped land at the urban boundary, sometimes resulting in an increase in total land under development.
Patients, Families, and Organ Donation: Who Should Decide?

Although 69 to 75 percent of U.S. adults say they would be willing to become organ donors, half of the families that are asked to consider donating the organs of a deceased family member refuse to consent. This discrepancy is most noticeable when the refusal of a family conflicts with the known wishes of a patient. It is the practice of nearly all organ procurement organizations in the United States not to procure organs or tissue when families refuse, even if the patient's wishes have been documented. Recently, the Center for Organ Recovery and Education (CORE) adopted a controversial policy of acting on the documented wishes of individuals to donate, independent of family consent. An examination of the moral and political issues raised by this policy lead to the conclusion that the CORE policy is not only justified, but morally required.
Room‐Temperature Thermal Conductivity of Cemented Transition‐Metal Carbides

Measurements are reported of the room-temperature thermal conductivity of cemented multicarbides (WC-TiCx-NbCx-TaCx/Co) and straight tungsten carbide (WC/Co), which are widely used tool materials. The thermal conductivity of cemented titanium carbide was found to be lower than that of cemented tungsten carbide. The difference is attributed to strong phonon and electron scattering from carbon atom vacancies in the nonstoichiometric cubic carbide TiCx; these defects are absent in stoichiometric hexagonal WC. Higher binder contents in tungsten carbide samples lowered the overall thermal conductivity. Scattering of electrons and phonons by C and W atoms in solid solution in the binder phase presumably reduces its thermal conductivity. No dependence on grain size was detected.
Regioselective Synthesis of Phenols and Halophenols from Arylboronic Acids Using Solid Poly(N‐vinylpyrrolidone)/ Hydrogen Peroxide and Poly(4‐vinylpyridine)/Hydrogen Peroxide Complexes

Solid hydrogen peroxide complexes based on poly(N-vinylpyrrolidone) and poly(4-vinylpyridine) were prepared and used as solid hydroxylating reagents. These solid hydrogen peroxide equivalents are found to be much safer, convenient and efficient reagent systems for the ipso-hydroxylation of arylboronic acids to the corresponding phenols in high yields at a faster rate. The versatility of the reagents has been further expanded for the one-pot synthesis of halophenols. Density functional theory calculations were carried out on hydrogen peroxide complexes of N-ethylpyrrolidone and 4-ethylpyridine as models to get a better understanding of structure and behavior of hydrogen peroxide complexes of the polymers poly(N-vinylpyrrolidone) and poly(4-vinylpyridine) compared to aqueous hydrogen peroxide.
A note on optimal care by wealth-constrained injurers

Abstract This paper clarifies the relationship between an injurer’s wealth level and his care choice by highlighting the distinction between monetary and non-monetary care. When care is non-monetary, wealth-constrained injurers generally take less than optimal care, and care is increasing in their wealth level under both strict liability and negligence. In contrast, when care is monetary, injurers may take too much or too little care under strict liability, and care is not strictly increasing in injurer wealth. Under negligence, the relationship between injurer care and wealth is similar in the two formulations. However, when litigation costs are added to the model, the relationship between injurer care and wealth becomes non-monotonic under both liability rules.
Distribution of intersection lengths of a random geodesic with a geodesic lamination

We investigate the distribution of lengths obtained by intersecting a random geodesic with a geodesic lamination. We give an explicit formula for the distribution for the case of a maximal lamination and show that the distribution is independent of the surface and lamination. We also show how the moments of the distribution are related to the Riemann zeta function.
Integrating Differentiated Services with ATM

IP in the edge and ATM in the core are commonplace in today's internetworks. The IETF has proposed a new Quality of Service (QoS) mechanism namely Differentiated Services (DiffServ) for IP networks. On the other hand, QoS is an inherent feature in ATM. It is imperative that IP and ATM QoS interoperate efficiently to provide an end-to-end service guarantee. DiffServ provides a class of service named Assured Forwarding (AF) that does not exactly correlate to any of the service categories offered by ATM. AF is targeted towards a range of applications, such as real-time (rt) that do not require a constant bit rate service provided by Expedited Forwarding, and other non-real-time (nrt) applications that expect a service better than best effort. In this paper we propose the mapping of AF to the Variable Bit Rate (VBR) service category in ATM. VBR is suitable because it is available in the form of rt-VBR and nrt-VBR and could be translated appropriately based on the applications. The mapping is implemented and verified using the LBNL Network Simulator. The results of the experiments show that VBR is a better match for AF than any other service category in ATM.
Conformal Equivalence of Analytic Functions on Compact Sets

In this paper we present a geometric proof of the following fact: Let D be a Jordan domain in $$\mathbb {C}$$ , and let f be analytic on cl(D). Then there is an injective analytic map $$\phi :D\rightarrow \mathbb {C}$$ , and a polynomial p, such that $$f\equiv p\circ \phi $$ on D (that is, f has a polynomial conformal model p).
Regulating Broiler Contracts: Tournaments Versus Fixed Performance Standards

Grower discontent with tournaments as mechanisms for settling poultry contracts can largely be attributed to the group composition risk that tournaments impose on growers. This article focuses on the welfare effects of a widely advocated regulatory proposal to prevent integrator companies from using tournaments and replace them with schemes that compare performance to a fixed standard. The analysis shows that the mandatory replacement of tournaments with fixed performance standards, absent any rules that regulate the magnitude of the piece rate, can decrease grower income insurance without raising welfare. However, replacing tournaments with fixed performance standards can simultaneously increase income insurance and welfare, provided that the magnitude of the piece rate is also regulated.
The Passions of Pluralism Multiculturalism and the Expanding Community

Changing demographies and the new immigrations are making the phenomenon of pluralism inescapable in this country. At once, what is recognized as an erosion of community requires us to find ways of reconciling a newly acknowledged diversity with a Deweyan notion of a "Great Community." Using imaginative works as well as philosophic and ethnographic books as texts, this article explores the significance of heeding multiple voices silenced over the years, of making them part of the ongoing "conversation" that distinguishes our culture. This entails an incorporation of visions seldom tapped before; it entails a recognition of exclusions and deficiencies long denied, a discovery of ways to fill the voids and in some fashion to repair. Finally, seeking a regard for distinctiveness as well as a reaching toward connectedness, I look for opportunities for concrete engagements, for imaginative efforts to cross the distances and look through diverse others" eyes.
Stiefel manifolds and coloring the pentagon

We prove Csorba@?s conjecture that the Lovasz complex Hom(C"5,K"n) of graph multimorphisms from the 5-cycle C"5 to the complete graph K"n is Z/2Z-equivariantly homeomorphic to the Stiefel manifold, V"n"-"1","2, the space of (ordered) orthonormal 2-frames in R^n^-^1.
Status of the Fermilab g−2 experiment

Abstract The upcoming muon ( g − 2 ) experiment at Fermilab will measure the anomalous magnetic moment of the muon to a relative precision of 140 ppb, 4 times better than the previous experiment at BNL. The new experiment is motivated by the persistent 3–4 standard deviations difference between the experimental value and the Standard Model prediction, and it will have the statistical sensitivity necessary to either refute the claim or confirm it with a confidence level exceeding a discovery threshold. The experiment is under construction and scheduled to start running in early 2017.
What does a random contingency table look like

Let R = (r1,. . ., rm) and C = (c1,. . ., cn) be positive integer vectors such that r1 + ⋯ + rm = c1 + ⋯ + cn. We consider the set Σ(R, C) of non-negative m × n integer matrices (contingency tables) with row sums R and column sums C as a finite probability space with the uniform measure. We prove that a random table D ∈ Σ(R, C) is close with high probability to a particular matrix (‘typical table’) Z defined as follows. We let g(x) = (x + 1)ln(x + 1) − x ln x for x ≥ 0 and let g(X) = ∑i,jg(xij) for a non-negative matrix X = (xij). Then g(X) is strictly concave and attains its maximum on the polytope of non-negative m × n matrices X with row sums R and column sums C at a unique point, which we call the typical table Z.
Adding nesting structure to words

We propose the model of nested words for representation of data with both a linear ordering and a hierarchically nested matching of items. Examples of data with such dual linear-hierarchical structure include executions of structured programs, annotated linguistic data, and HTML/XML documents. Nested words generalize both words and ordered trees, and allow both word and tree operations. We define nested word automata—finite-state acceptors for nested words, and show that the resulting class of regular languages of nested words has all the appealing theoretical properties that the classical regular word languages enjoys: deterministic nested word automata are as expressive as their nondeterministic counterparts; the class is closed under union, intersection, complementation, concatenation, Kleene-a, prefixes, and language homomorphisms; membership, emptiness, language inclusion, and language equivalence are all decidable; and definability in monadic second order logic corresponds exactly to finite-state recognizability. We also consider regular languages of infinite nested words and show that the closure properties, MSO-characterization, and decidability of decision problems carry over.The linear encodings of nested words give the class of visibly pushdown languages of words, and this class lies between balanced languages and deterministic context-free languages. We argue that for algorithmic verification of structured programs, instead of viewing the program as a context-free language over words, one should view it as a regular language of nested words (or equivalently, a visibly pushdown language), and this would allow model checking of many properties (such as stack inspection, pre-post conditions) that are not expressible in existing specification logics.We also study the relationship between ordered trees and nested words, and the corresponding automata: while the analysis complexity of nested word automata is the same as that of classical tree automata, they combine both bottom-up and top-down traversals, and enjoy expressiveness and succinctness benefits over tree automata.
Nonlinear Inviscid Aerodynamic Effects on Transonic Divergence, Flutter, and Limit-Cycle Oscillations

By the use of a state-of-the-art computational e uid dynamic (CFD) method to model nonlinear steady and unsteady transonice owsin conjunction with a linearstructural model,an investigationismadeinto how nonlinear aerodynamics can effect the divergence, e utter, and limit-cycle oscillation (LCO) characteristics of a transonic airfoil cone guration. A single-degree-of-freedom (DOF) model is studied for divergence, and one- and two-DOF models are studied for e utter and LCO. A harmonicbalancemethod in conjunction with the CFD solver is used to determine the aerodynamics for e nite amplitude unsteady excitations of a prescribed frequency. A procedure for determining the LCO solution is also presented. For the cone guration investigated, nonlinear aerodynamic effects are found to produce a favorable transonic divergence trend and unstable and stable LCO solutions, respectively, for the one- and two-DOF e utter models. Nomenclature a = nondimensional location of airfoil elastic axis, e=b b, c = semichord and chord, respectively cl, cm = coefe cients of lift and moment about elastic axis, respectively e = location of airfoil elastic axis, measured positive aft of airfoil midchord h, ® = airfoil plunge and pitch degrees of freedom I® = second moment of inertia of airfoil about elastic axis
Experiments with Digital Computer Simulations of Pseudo-Random Noise Generators

One of the most useful binary linear sequential machines is the maximal-length linear sequence generator. These are sometimes known as pseudo-noise generators because of certain statistical characteristics of their output. One of the more tedious problems in the application of -these generators has long been the calculation of the time displacement of the vectors constituting the output bit stream. In the past, this has been accomplished by programming a computer to simulate the generator and counting steps to the wanted output vector. We show in this paper a much simpler solution to the problem which can be accomplished by means of simple hand calculations.
Estimating the Impact of Investment Tax Credits on Aircraft Demand

This paper uses exogenous price changes from the shifting tax policies of the 1980’s to identify the parameters of a nested-logit discrete choice model of the aircraft market. The federal Investment Tax Credit (ITC) was a tax credit of 6-10% of a firm's new capital investment that was removed by the Tax Reform Act of 1986 (TRA86). Such tax credits continue to be proposed as tools to spur investment, and they are still utlized in many states and select industries. This research adds to the small body of empirical work on taxes in imperfectly competitive markets. I model the oligopoly market structure of aircraft manufacturers by assuming Bertrand competition. The demand-side parameters are estimated using 2SLS with cost-shifting instruments. The demand-side choices are purchasing new or used aircraft, or refraining from purchasing an aircraft. I then estimate linear mark-up equations using the demand-side parameter estimates and other cost variables. I use the full set of parameter estimates to simulate aircraft transactions before and after the TRA86. This structural approach allows me to isolate the effects of the ITC through counterfactual policy simulations. I find that the ITC encourages firms to upgrade to more expensive capital by purchasing a more expensive aircraft than they would have without the ITC; however, the ITC has very limited impact enticing firms to purchase new aircraft instead of used aircraft. The overall effect on new purchases is small. Thus, most of the incidence of the tax credit was gained by the suppliers of aircraft; moreover the ITC exacerbated the market power of suppliers, leading to further distortions.
Computer sizing of fighter aircraft

The computer sizing technique has been applied to a number of military mission profiles. Performance data can be determined for all segments of the selected profile, which typically include takeoff, climb, cruise, loiter, reserve and landing segments. Options are available for detailed calculation of combat performance and energy-maneuverability characteristics. Configuration changes, such as external fuel tank drop and weapon expenditure, can be included in the mission. In the sizing mode, aircraft gross weight, wing loading, and thrust-to-weight ratio are varied automatically to determine which combinations meet the design mission radius. The resulting performance data can be used to create a thumbprint plot. This plot is useful in determining the configuration size that best satisfies the mission and performance requirements. The sizing mode can also be used to perform parametric studies such as sensitivity of gross weight to alternate design conditions.
Adaptive Sentence Boundary Disambiguation

Labeling of sentence boundaries is a necessary prerequisite for many natural language processing tasks, including part-of-speech tagging and sentence alignment. End-of-sentence punctuation marks are ambiguous; to disambiguate them most systems use brittle, special-purpose regular expression grammars and exception rules. As an alternative, we have developed an efficient, trainable algorithm that uses a lexicon with part-of-speech probabilities and a feed-forward neural network. This work demonstrates the feasibility of using prior probabilities of part-of-speech assignments, as opposed to words or definite part-of-speech assignments, as contextual information. After training for less than one minute, the method correctly labels over 98.5% of sentence boundaries in a corpus of over 27,000 sentence-boundary marks. We show the method to be efficient and easily adaptable to different text genres, including single-case texts.
Organizational Management Styles, Employee Supervisory Status, and Employee Responses

Employees' perceptions, attitudes, and behaviors are compared in two automotive supply organizations that are similar in size, technology, industry, employee characteristics, and geographic location, but are different in formal management styles. The data are examined separately for supervisors and production workers to identify hierarchical differences. Overall, the results indicate that rank-and-file employees' perceptions, attitudes, and behaviors are more favorable in the organization with the more democratic formal managerial style than in the more traditional organization, but there is very little difference in the responses of the supervisors between the two environments. Future research directions are suggested that would further enhance our understanding of the potential impact of managerial styles on employee responses at different hierarchical levels.
Multiple description coding of discrete ergodic sources

We investigate the problem of Multiple Description (MD) coding of discrete ergodic processes. We introduce the notion of MD stationary coding, and characterize its relationship to the conventional block MD coding. In stationary coding, in addition to the two rate constraints normally considered in the MD problem, we consider another rate constraint which reflects the conditional entropy of the process generated by the third decoder given the reconstructions of the two other decoders. The relationship that we establish between stationary and block MD coding enables us to devise a universal algorithm for MD coding of discrete ergodic sources, based on simulated annealing ideas that were recently proven useful for the standard rate distortion problem.
A Model of Search Intermediaries and Paid Referrals

In this paper we pursue three main objectives: (1) to develop a model of an intermediated search market in which matching between consumers and firms takes place primarily via paid referrals; (2) to address the question of designing a suitable mechanism for selling referrals to firms; and (3) to characterize and analyze the firms' bidding strategies given consumers' equilibrium search behavior. To achieve these objectives we develop a two-stage model of search intermediaries in a vertically differentiated product market. In the first stage an intermediary chooses a search engine design that specifies to which extent a firm's search rank is determined by its bid and to which extent it is determined by the product offering's performance. In the second stage, based on the search engine design, competing firms place their open bids to be paid for each referral by the search engine. We find that the revenue-maximizing search engine design bases rankings on a weighted average of product performance and bid amount. Nonzero pure-strategy equilibria of the underlying discontinuous bidding game generally exist but are not robust with respect to noisy clicks in the system. We determine a unique nondegenerate mixed-strategy Nash equilibrium that is robust to noisy clicks. In this equilibrium firms of low product performance fully dissipate their rents, which are appropriated by the search intermediary and the firm with the better product. The firms' expected bid amounts are generally nonmonotonic in product performance and depend on the search engine design parameter. The intermediary's profit-maximizing design choice, by attributing a positive weight to the firms' bids, tends to obfuscate search results and reduce overall consumer surplus compared to the socially optimal design of fully transparent results ranked purely on product performance.
The impact of regulation Fair Disclosure on investors' prior information quality — Evidence from an analysis of changes in trading volume and stock price reactions to earnings announcements ☆

We document that Regulation Fair Disclosure has reduced differences in information quality between investors prior to quarterly earnings announcements consistent with the intent of the regulation. This reduction is driven by small firms and high technology firms, rather than the large firms targeted by the SEC, which suggests that selective disclosure among large firms may have been much more limited than what was presumed by proponents of FD. In addition, we document that FD has decreased the average information quality of investors in small and high technology firms in the period prior to an earnings announcement while having no lasting effect on other firms. Taken together these two results suggest that, for small and high technology firms, FD succeeded in eliminating selective disclosure but also lowered the average quality of information available about these firms.
The minimal dimension of stable faces required to guarantee stability of a matrix polytope: D-stability

The problem of determining whether a polytope P of n*n matrices is D-stable-i.e. whether each point in P has all its eigenvalues in a given nonempty, open, convex, conjugate-symmetric subset D of the complex plane-is discussed. An approach which checks the D-stability of certain faces of P is used. In particular, for each D and n the smallest integer m such that D-stability of every m-dimensional face guarantees D-stability of P is determined. It is shown that, without further information describing the particular structure of a polytope, either (2n-4)-dimensional or (2n-2)-dimensional faces need to be checked for D-stability, depending on the structure of D. Thus more work needs to be done before a computationally tractable algorithm for checking D-stability can be devised. >
Profitability and Long-term Survival of Community Banks: Evidence from Texas

This study examines the impact of distance among competing bank locations on market their pricing behavior. A general spatial autoregressive model that nests both spatial autoregressive and spatial error models is used to examine the impact of distance on pricing behavior of 686 non-metro banks in Texas. Results show that non-metro banks exercise market power in pricing their products. An increase in spatial competition may reduce profitability and challenge long term survival of small community based financial institutions.
A comparison of knowledge obsolescence of graduating seniors and practitioners in the field of physical education.

Abstract The issue of defining and measuring professional obsolescence among physical educators is examined through a comparison of the current knowledge base of graduating physical education seniors and physical education practitioners in Pennsylvania. In a previous study, the “Inventory of Recent Knowledge in Physical Education,” a 260-item sample of current knowledge as defined by content experts was developed by the authors and administered by mail to the population of 2,737 male professional members of the public school districts' departments of physical education in Pennsylvania. In the present study, results from the first study were compared with those from an administration of the same instrument to 462 female and male physical education majors graduating from nine Pennsylvania higher education institutions. Both studies employed multiple-matrix procedures for item-person sampling and data analysis. An analysis of the results for both groups showed essentially similar performance profiles on the ...
Occupation-Specific Human Capital and Local Labor Markets

Most skills acquired through on-the-job training may be specific to an occupation and therefore transferable to some but not all firms. This paper explores the relationship between the size of the local market for an occupation-specific skill and job-training outcomes. The Stevens (1994) model of training predicts that as market size increases, job turnover increases and training becomes more general. I test these predictions using data on blue-collar workers and variation in market size across U.S. metropolitan areas. The empirical results support the theoretical predictions and the impacts are most relevant at low levels of market size.
VECTOR BUNDLES, DUALITIES AND CLASSICAL GEOMETRY ON A CURVE OF GENUS TWO

Let C be a curve of genus two. We denote by $\mathcal{SU}_C(3)$ the moduli space of semi-stable vector bundles of rank 3 and trivial determinant over C, and by Jd the variety of line bundles of degree d on C. In particular, J1 has a canonical theta divisor Θ. The space $\mathcal{SU}_C(3)$ is a double cover of ℙ8 = |3Θ| branched along a sextic hypersurface, the Coble sextic. In the dual $\check{\mathbb{P}}^{8} = |3\Theta|^{*}$, where J1 is embedded, there is a unique cubic hypersurface singular along J1, the Coble cubic. We prove that these two hypersurfaces are dual, inducing a non-abelian Torelli result. Moreover, by looking at some special linear sections of these hypersurfaces, we can observe and reinterpret some classical results of algebraic geometry in a context of vector bundles: the duality of the Segre–Igusa quartic with the Segre cubic, the symmetric configuration of 15 lines and 15 points, the Weddle quartic surface and the Kummer surface.
Virtual organizing: using threads to coordinate distributed work

This paper explores the critical role of conversational threads in facilitating the ongoing, distributed work of one virtual organization. In studying the electronic mail exchanges of organizational members during one year, we found that they engaged in a range of threading activity to establish and maintain continuity, coherence, and coordination in their collaborative work over time. In particular, we found that organizational members relied on simple threads to focus their attention and action on a particular topic over a short period of time, concurrent threads to enable their participation in multiple topics at the same time, and compound threads to allow provisional settlement of key issues that were subsequently revisited over extended periods of time. We conclude by discussing the implications of conversational threads for research and practice of virtual organizing.
Soft Sensing and Optimal Power Control for Cognitive Radio

We consider a cognitive radio system where the secondary transmitter varies its transmit power based on the information available from the spectrum sensor. The operation of the secondary user is governed by its peak transmit power constraint and an average interference constraint at the primary receiver. Without restricting the sensing scheme (total received energy, or correlation etc), we characterize the power adaptation strategies that maximize the secondary user's SNR and capacity. We show that, in general, the capacity optimal power adaptation requires decreasing the secondary transmit power from the peak power to zero in a continuous fashion as the probability of the primary user being present increases. In contrast, we find that that power control that maximizes the SNR is binary, i.e., if there is any transmission, it takes place only at the peak power level. Numerical results for common spectrum sensing schemes show that the SNR and capacity maximizing schemes can be very different. With an average transmit power constraint at the secondary radio, both the SNR and capacity optimal power control schemes are observed to be non-binary. Further, we find that with secondary channel knowledge at the cognitive transmitter, the optimal SNR with an average transmit power constraint is unbounded.
Gain stabilization of a submillimeter SIS heterodyne receiver

We have designed a system to stabilize the gain of a submillimeter heterodyne receiver against thermal fluctuations of the mixing element. In the most sensitive heterodyne receivers, the mixer is usually cooled to 4 K using a closed-cycle cryocooler, which can introduce /spl sim/1%; fluctuations in the physical temperature of the receiver components. We compensate for the resulting mixer conversion gain fluctuations by monitoring the physical temperature of the mixer and adjusting the gain of the IF amplifier that immediately follows the mixer. This IF power stabilization scheme, developed for use at the Submillimeter Array, a submillimeter interferometer telescope located on Mauna Kea, HI, routinely achieves a receiver gain stability of one part in 6000 (rms to mean). This is an order of magnitude improvement over the typical uncorrected stability of one part in a few hundred. Our gain stabilization scheme is a useful addition to superconductor-insulator-superconductor heterodyne receivers that are cooled using closed-cycle cryocoolers in which the 4-K temperature fluctuations tend to be the leading cause of IF power fluctuations.