cssi/SciSciGPT-SciSciNet huggingface dataset:
Strong near-infrared luminescence in BaSnO3.

Powdered samples of the perovskite BaSnO3 exhibit strong near-infrared (NIR) luminescence at room temperature, following band-gap excitation at 380 nm (3.26 eV). The emission spectrum is characterized by a broad band centered at 905 nm (1.4 eV), tailing on the high-energy side to approximately 760 nm. The Stokes shift is 1.9 eV, and measured lifetimes in the range 7−18 ms depend on preparative conditions. These extraordinary long values indicate that the luminescence involves a defect state(s). At low temperatures, both a sharp peak and a broad band appear in the visible portion of the luminescence spectrum at approximately 595 nm. Upon cooling, the intensity of the NIR emission decreases, while the integrated intensities of the visible emission features increase to approximately 40% of the NIR intensity at 77 K. Room-temperature photoluminescence (PL) is observed across the Ba1-xSrxSnO3 series. As the strontium content increases, the excitation maximum and band gap shift further into the UV, while the in...
Gain spectrum spikes in FEL amplifiers

Abstract Sharp spikes can appear far from resonance in the gain spectrum of high-gain, high-power FEL amplifiers with good beam quality. At the spike, gain is larger than in the rest of the broad, smooth gain spectrum.
Automated counting of lego towers

H.N.V. Temperley's method for counting vertically convex polyominoes is modified, generalized, and most importantly, programmed (in Maple).
Dietary protein enterocolitis.

Dietary protein enterocolitis generally presents in the 1st year of life with diarrhea, emesis, and irritability. When there is a delay in diagnosis, persistent exposure to the offending dietary antigen leads to increasing enteric inflammation manifesting as bloody diarrhea, anemia, dehydration, and failure to sustain normal patterns of weight gain and growth. The extent of enteric inflammation may be limited to mild proctitis, pancolitis, or true enterocolitis with esophagitis, gastritis, enteropathy, and colitis. The offending antigen is usually cow's milk protein or soy protein. A significant number of the infants are exclusively breast fed, especially those with proctitis. In older children, a wide variety of dietary proteins have been implicated. The inconsistency between allergists and gastroenterologists in the clinical definition of the syndrome remains a significant problem. To the allergist, the definition is based on clinical criteria, allergy testing, and response to double-blind food challenge, whereas to the gastroenterologist, it is defined by histologic criteria and the response of clinical and histologic manifestations to elimination diets. To further complicate the issue, European studies have emphasized the alterations in enteric permeability noted in both enteropathy and enterocolitis. In an effort to establish a unified approach, the International Life Sciences Institute sponsored a workshop in late 1998, which resulted in a document entitled "Classification of Gastrointestinal Disease of Infants and Children Due to Adverse Immunologic Reactions."
A unique framework in BaGa2Sb2: a new Zintl phase with large tunnels.

BaGa2Sb2 was obtained from a direct element combination reaction in a sealed graphite tube at 950 °C, and its structure was determined by single-crystal X-ray diffraction methods. It crystallizes in the orthorhombic space group Pnma (No. 62) with a = 25.454(5) A, b = 4.4421(9) A, c = 10.273(6) A, and Z = 8. The anionic [Ga2Sb6/3]2- framework is assembled by the ethane-like dimeric [Sb3Ga−GaSb3] units sharing Sb atoms, forming parallel tunnels with a 26-membered ring cross section. These tunnels are filled with Ba atoms. The three-dimensional [Ga2Sb6/3]2- framework features a new structure type. The compound satisfies the classical Zintl concept. Band structure calculations indicate that the material is a semiconductor, and this is confirmed by spectroscopic experiments which show Eg ∼ 0.35 eV. The calculations also suggest that the structure is stabilized by strong Ga−Ga covalent bonding interactions. Polycrystalline ingots of BaGa2Sb2 show room-temperature electrical conductivity of ∼65 S/cm and a Seebec...
ItswTCM: a new aggregate marker to improve fairness in DiffServ

Recent demands for real time applications have given rise to a need for Quality of Service (QoS) in the Internet. Differentiated Services (DiffServ) is one of such efforts currently pursued by IETF. Previous researchers found unfairness in the DiffServ network. To solve the unfairness problem, we propose a new TSW based three-color marker (ItswTCM), which achieves proportional fair share of excess bandwidth among aggregates in a DiffServ network. We have compared the fairness of our proposed ItswTCM marker with srTCM, trTCM, and tswTCM. Results show that our proposed marker performs better than the other three schemes for low to medium network provision level (20-70%); we believe that all well provisioned network will operate in this region. Results also show that our proposed marker is not as sensitive to the number of flows in an aggregate as the previous marking schemes. We point out that yellow packets play a significant role in achieving proportional fair share of excess bandwidth among aggregates. We conclude that in order to achieve proportional fair sharing of excess bandwidth, it is important to inject right amount of yellow packets into the network.
An optimization model for time-sharing

The proper design of scheduling processes for time-shared computers has provoked much discussion. One of the factors promoting discussion is the great variety of scheduling procedures which one can feasibly program, and which will operate with adequate efficiency. There is wide latitude for conjecturing possibly improved procedures. Moreover, the performance requirements of time-sharing demand more sophisticated schemes than one can analyze with simple queueing theory, yet it is not feasible to experiment with many alternative procedures in operational systems and produce quantitative evidence of their relative merits.
Haplosamates A and B: New steroidal sulfamate esters from two haplosclerid sponges

Abstract Two sponges from the Philippines, one a Xestospongia sp. (Haplosclerida, Petrosiidae) and the other an unidentified haplosclerid sponge, both contained the unusual steroidal sulfamate esters, haplosamates A ( 1 ) and B ( 2 ), the structures of which were determined by interpretation of spectral data. Haplosamates A ( 1 ) and B ( 2 ) inhibit HIV-1 integrase with IC 50 's of 50μg/mL and 15μg/mL, respectively.
Establishment Size and Job Tenure

A central hypothesis of the theory of labor market segmentation is that large establishments tend to establish circumstances of employment which foster employment stability. According to this view, large employers stabilize their labor relations by instituting job ladders, grievance procedures, and seniority provisions governing pay, promotion, layoffs, and recalls (see Edwards, 1979; Gordon et al., 1982). These structures, often referred to as internal labor markets, are understood to be key institutional underpinnings of labor market segmentation (see Doeringer and Piore, 1971). This paper tests the supposed relationship between large employers and employment stability by focusing on the effect of plant size and firm size on job tenure. Previous econometric studies of the determinants of job tenure have looked closely at such factors as unionization, hourly earnings, and fringe benefits, but they have ignored the effect of the size of the establishment (Freeman, 1980a,b; Freeman and Medoff, 1984; Leigh, 1970; Merrilees, 1981). Recent studies of individual quit decisions and turnover experience have also overlooked employer size (e.g., Steinberg, 1975; Blau and Kahn, 1981, 1983; Mitchell, 1982; Schiller and Weiss, 1979).
The emergence of Consumer Introspection Theory (CIT): Introduction to a JBR special issue

Abstract Introspection in its various forms, names, paradigmatic controversies and especially its power for insight has earned its place as a topic for a special issue. Here, I introduce this issue in terms of the introspections it contains and introspect a bit myself mainly through introspective thought exercises. What I find grounded in the texts of the submitted papers as thematic data is an emergent (rebranded) perspective on introspection which I call, Consumer Introspection Theory (CIT). I relate CIT as a paradigm to different forms of research: Consumer Culture Theory (CCT), critical marketing and experimental research. I also further elaborate how it functions in terms of single versus multiple person introspection, autoethnography and other practice variations; narrative versus metacognitive introspection; grounded versus hypothesis-driven introspection and introspective thought exercises.
Detection of incompressible surfaces in hyperbolic punctured torus bundles

Culler and Shalen, and later Yoshida, give ways to construct incompressible surfaces in 3-manifolds from ideal points of the character and deformation varieties, respectively. We work in the case of hyperbolic punctured torus bundles, for which the incompressible surfaces were classified by Floyd and Hatcher, and independently by Culler, Jaco and Rubinstein. We convert non fiber incompressible surfaces from their form to the form output by Yoshida’s construction, and run his construction backwards to give (for non semi-fibers, which we identify) the data needed to construct ideal points of the deformation variety corresponding to those surfaces via Yoshida’s construction. We use a result of Tillmann to show that the same incompressible surfaces can be obtained from an ideal point of the character variety via the Culler-Shalen construction. In particular this shows that all boundary slopes of non fiber and non semi-fiber incompressible surfaces in hyperbolic punctured torus bundles are strongly detected.
Matching is as easy as matrix inversion

We present a new algorithm for finding a maximum matching in a general graph. The special feature of our algorithm is that its only computationally non-trivial step is the inversion of a single integer matrix. Since this step can be parallelized, we get a simple parallel (RNC 2) algorithm. At the heart of our algorithm lies a probabilistic lemma, the isolating lemma. We show other applications of this lemma to parallel computation and randomized reductions.
Basic hydrolysis of glyceryl nitrate esters. I. 1‐glyceryl and 2‐glyceryl nitrate esters

Kinetics of the basic hydrolysis of 1,2-glyceryl dinitrate (1,2-DNG) and 1,3-glyceryl dinitrate (1,3-DNG) esters were investigated in CO2-free aqueous calcium hydroxide solutions. The hydrolysis reactions were carried out in a temperature controlled reactor vessel with provision for continuous N2 sparging of the reaction mixture. Both glyceryl dinitrate esters hydrolyzed via second-order reaction at 25°C. 1,2-DNG in basic solutions isomerized to 1,3-DNG which subsequently hydrolyzed to yield products. The main hydrolysis product of 1,3-DNG was identified as glycidyl nitrate. Other products formed during the basic hydrolysis of DNGs were nitrites and nitrates.
Localization in non-Hermitian quantum mechanics and flux-line pinning in superconductors

Abstract A recent development in studies of random non-Hermitian quantum systems is reviewed. Delocalization was found to occur under a sufficiently large constant imaginary vector potential even in one and two dimensions. The phenomenon has a physical realization as flux-line depinning in type-II superconductors. Relations between the delocalization transition and the complex energy spectrum of the non-Hermitian systems are described. Analytical and numerical results obtained for a non-Hermitian Anderson model are shown.
Optimal futures contract design

Abstract Designing successful futures contracts is no easy task. Most new contracts fail to attract a sustainable level of trading volume. A comparatively new approach to identifying the attributes of successful futures contracts comes from applying the emerging literature on security design to the futures problem. A second and more complicated issue is to determine the optimal contract form. This paper describes the characteristics of successful futures contracts implied by the design literature, and, where possible, relates these observations to empirical studies. The paper also describes how the design literature can be applied to reveal the link between the specific terms of successful futures contracts to characteristics of the cash market.
Minmax regret 1-facility location on uncertain path networks

Abstract Let P be an undirected path graph of n vertices. Each edge of P has a positive length and a constant capacity. Every vertex has a nonnegative supply, which is an unknown value but is known to be in a given interval. The goal is to find a point on P to build a facility and move all vertex supplies to the facility such that the maximum regret is minimized. The previous best algorithm solves the problem in O ( n log 2 n ) time and O ( n log n ) space. In this paper, we present an O ( n log n ) time and O ( n ) space algorithm, and our approach is based on new observations and algorithmic techniques.
Role of impurities in silicon solar cell performance

Abstract This paper is a review of recently acquired information relevant to the effects of impurities in silicon on solar cell performance and to the determination of tolerable impurity levels. The primary effects of both bulk and surface contamination on performance parameters are discussed and the concentration levels of concern for oxygen and several metallic impurities are shown to be in the range 1012 − 1014 atoms cm−3. Levels of contamination and activation of impurities that can be encountered during the conventional processing of solar cell substrates are discussed and illustrated by selected candidate sources of performance degradation. The impurity content of a silicon substrate imposes an upper limit on the performance of solar cells fabricated on the substrate. The severity of the imposed limit depends on the kinds, concentrations and distributions of the impurities and on their electronic state within the lattice. The purpose of this paper is to indicate the sensitivity of solar cell performance parameters to the concentration of some impurities and to illustrate the manner in which these impurities degrade solar cell performance.
Radiation damage in silicon detectors

Abstract A review is presented of the effects of radiation damage on silicon detectors, which are being considered for high energy physics applications. The main degradation in performance is an increase in leakage current, which can be well characterized by an empirical damage constant for many radiations. A summary of data on damage constants is given. A brief discussion of annealing effects in terms of band gap level changes is included.
Hidden duality and associated instabilities of Tomonaga–Luttinger liquid on lattice

Abstract Hidden duality and its associated instabilities of the spinless Luttinger liquid on lattice are reported. The local quantum fluctuations due to the general multi-particle umklapp and other processes and the long-distance chiral modes compete and as a result produce a hierarchy of exotic charge/density instabilities. Explicit bosonic quantum operators for the local density fluctuations are constructed and are used to make identification of the Luttinger liquid with the classical 2D Coulomb gas with θ -term and with the rich hidden duality.
Neural network learning of optimal Kalman prediction and control

Although there are many neural network (NN) algorithms for prediction and for control, and although methods for optimal estimation (including filtering and prediction) and for optimal control in linear systems were provided by Kalman in 1960 (with nonlinear extensions since then), there has been, to my knowledge, no NN algorithm that learns either Kalman prediction or Kalman control (apart from the special case of stationary control). Here we show how optimal Kalman prediction and control (KPC), as well as system identification, can be learned and executed by a recurrent neural network composed of linear-response nodes, using as input only a stream of noisy measurement data.The requirements of KPC appear to impose significant constraints on the allowed NN circuitry and signal flows. The NN architecture implied by these constraints bears certain resemblances to the local-circuit architecture of mammalian cerebral cortex. We discuss these resemblances, as well as caveats that limit our current ability to draw inferences for biological function. It has been suggested that the local cortical circuit (LCC) architecture may perform core functions (as yet unknown) that underlie sensory, motor, and other cortical processing. It is reasonable to conjecture that such functions may include prediction, the estimation or inference of missing or noisy sensory data, and the goal-driven generation of control signals. The resemblances found between the KPC NN architecture and that of the LCC are consistent with this conjecture.
A simple model of efficient tort liability rules

Abstract We present a simple model of tort liability in which precaution is a binary choice, and, if any party takes precaution, the probability of accidents is zero. We compare and contrast our model to other models in which precaution is a continuous variable. Our paper provides easy characterizations of the efficiency properties of a number of real and hypothetical liability rules, including no liability, Learned Hand negligence, negligence with contributory negligence as a defense, Calabresi and Hirschoff’s reverse Hand, Galena, Brown’s relative negligence, strict liability, and others. In a mathematical appendix we extend the model and derive efficiency propositions for dichotomous-action, multidefendant liability rules of various types: simple (in which one party pays 100% of accident costs); comparative negligence (in which accident costs may be spread among two or more parties); and punitive damages (in which some parties may pay more than 100% of accident costs).
MULTIPLE COMPONENT OUTFLOWS IN AN ACTIVE REGION OBSERVED WITH THE EUV IMAGING SPECTROMETER ON HINODE

We have used the Extreme Ultraviolet Imaging Spectrometer on the Hinode spacecraft to observe large areas of outflow near an active region. These outflows are seen to persist for at least 6 days. The emission line profiles suggest that the outflow region is composed of multiple outflowing components, Doppler-shifted with respect to each other. We have modeled this scenario by imposing a double-Gaussian fit to the line profiles. These fits represent the profile markedly better than a single-Gaussian fit for Fe XII and XIII emission lines. For the fastest outflowing components, we find velocities as high as 200 km s{sup -1}. However, there remains a correlation between the fitted line velocities and widths, suggesting that the outflows are not fully resolved by the double-Gaussian fit and that the outflow may be comprised of further components.
Development of a novel protocol for isolation and purification of human granulosa cells

Purpose To develop an optimal method of isolation and purification of human granulosa cells from ovarian follicular fluid.
Commonality of processes underlying visual and verbal recognition memory

Memory for visual and verbal material engages widely distributed systems, to a large degree focussed in different hemispheres. It might thus be expected that these disparate neuronal populations should display significantly different characteristics in regard to mnemonic performance. Visual memory, fundamental to all human beings, and whose characteristics are largely shared with macaques, was assayed using unique non-objective, colored images lacking ready verbal description and was contrasted with memory for four-letter non-offensive English words. The effects of memory loading, stimulus duration and long-term test intervals (1–2 weeks) were studied in regard to accuracy and reaction times for recognizing initial versus re-exposure to these two types of items. No effects of memory loading were apparent despite the incrementing memory load in the 240-item, running recognition sessions. Words were better remembered than images, both in the long and short term, but the detailed characteristics of reaction times and accuracy in relation to number of intervening items, and in long-term memory were strikingly similar. Given the wide and well-established disparity in cerebral loci participating in linguistic versus image analysis, these multiple similarities in the pattern of mnemonic performance indicate that the underlying neuronal processes must be comparable for remembering either images or words. Furthermore, the strong link manifested between individual items across a varying number of intervening intervals and added items suggests that a phenomenon highly similar to the “stimulus specific adaptation” (SSA), displayed by units in macaque inferotemporal cortex, occurs for each item to be recognized. Finally, the significant augmentation in accuracy both in short- and long-term memory for images when viewing time permits saccades is explained if each saccade and fixational pause recruits additional neurons into the pool displaying SSA, or its equivalent, for the item being viewed.
Transient Boundary-Layer Flows in Combustion Environments

UNSTEADY boundary-layer flow equations characterizing hot, burning environments are solved numerically by means of a factored ADI method under transient and/or stream wise varying core-flow conditions. Calculated results for compressible, turbulent flow cases show that high heat fluxes at the wall due to turbulence and changing edge conditions may bring about severe temperature increase at the wall, causing eventually melting and, hence, erosion of the surface itself. Contents The present work describes numerical analysis of the surface-temperature history when the surface is exposed to hot, turbulent flow conditions, such as in rocket nozzles and other combustion environments. The formulation includes equations involving conservation of the mass, momentum, and thermal energy in the unsteady, turbulent, compressible boundary layer adjacent to the wall under assumptions of thermodynamic equilibrium and the Cebeci-Smith eddy viscosity model.! Detailed expressions for these conservation equations are given in Ref. 2. An additional equation is needed to account for the timewise response of the surface temperature due to the transient heat flux at the wall transferring energy from the core through the turbulent boundary layer to the surface. Assuming the heat flow direction inside the solid material to be normal to the surface, the surface temperature history for a variable (timewise) heat flux at the surface is determined to be
The Unusual Luminosity Function of the Globular Cluster M10

We present the I-band luminosity function of the differentially reddened globular cluster M10. We combine photometric analysis derived from wide-field (23' × 23') images that include the outer regions of the cluster and high-resolution images of the cluster core. After making corrections for incompleteness and field star contamination, we find that the relative numbers of stars on the lower giant branch and near the main-sequence turnoff are in good agreement with theoretical predictions. However, we detect significant (>6 σ) excesses of red giant branch stars above and below the red giant branch bump using a new statistic (a population ratio) for testing relative evolutionary timescales of main-sequence and red giant stars. The statistic is insensitive to assumed cluster chemical composition, age, and main-sequence mass function. The excess number of red giants cannot be explained by reasonable systematic errors in our assumed cluster chemical composition, age, or main-sequence mass function. Moreover, M10 shows excesses when compared to the cluster M12, which has nearly identical metallicity, age, and color-magnitude diagram morphology. We discuss possible reasons for this anomaly, finding that the most likely cause is a mass function slope that shows significant variations as a function of mass.
Skin infections in athletes

Athletic participation has increased in popularity in the past several decades. Unfortunately, athletic activity results in many types of dermatoses. Infectious conditions exemplify the most common cutaneous ailments of athletes. Fungal, bacterial and viral infections represent the majority of skin infections in athletes. For a variety of intrinsic and extrinsic factors, athletes experience an increased risk of these cutaneous infections. Once infected, athletes may endure loss of practice time and disqualification from competition. Rapid diagnosis, appropriate institution of therapy and attentive prevention programs all minimize the deleterious effects of skin infections for both the athlete and the team.
Thin-film transparent thermocouples☆

Abstract Transparent thin-film electrical conductors have been sputter deposited to form transparent thermocouples. Indium-tin oxide (ITO) and antimony-tin oxide (ATO) have demonstrated Seebeck coefficients of 7–77 μV/°C, depending on their conductivity and fabrication parameters. In addition to results for in-house-fabricated thermocouples, thermoelectric measurements are reported on commercial ATO, ITO, and fluorine-doped tin oxide transparent films.
Should Central Banks Burst Bubbles? Some Microeconomic Issues

Anti-bubble policy is examined in a finite-horizon ‘greater fool’ bubble model, with rational agents, asymmetric information and short-sales constraints. This permits the use of standard tools of welfare economics to analyse bubble policies. Policy is modelled as deflating overpriced assets by revealing information about this overpricing. If the central bank is following such a policy, then the market interprets inaction as an implicit endorsement of asset prices, which raises these prices. Also, the central bank can deflate overpriced assets even if it has no informational advantage over any investors about this overpricing. However, unless it has such an informational advantage, a bubble-bursting rule may only make things worse.
Three-dimensional structural analysis using interactive graphics

Abstract Three-dimensional finite element structural analysis computer programs can only be used effectively when the input can be accurately generated and checked, and the output correctly examined. With the use of the Sandia Interactive Graphics System, SIGS, which consists of a cathode ray tube, a mini-computer, a CDC 6600 computer and an interactive graphics computer software system, both input and output can be effectively and efficiently processed. Examining three-dimensional objects is made practical by rotation of the object in real time with hardware and with hidden line removal. A computer program has been written with which the analyst can interactively supply and correct data to generate a three-dimensional mesh. Output processing is accomplished by describing planes which cut the three-dimensional object; then contour plots of outputted variables and deformed mesh plots are produced.
A SURVEY OF PROGRESS IN GRAPH THEORY IN THE SOVIET UNION

Abstract : The report describes the results of a comprehensive technical survey of all published Soviet literature in graph theory and its applications--more than 230 technical articles appearing up to June 1968. The purpose of this report is to draw attention to this collection of results, which are not well known in the West, and to summarize the significant contributions. Particular emphasis is placed upon those results that fill gaps or augment the body of knowledge about graph theory as familiar to non-Soviet specialists.
Sodium-sulfur battery flight experiment definition study

Abstract The need for high power space systems in anticipated within the next 10 to 20 years. Examples are the Space Station, co-orbiting platforms, geostationary orbit (GEO) platforms, and space-based radar satellites and some classified high power missions. Sodium-sulfur (NaS) batteries have been identified as the most likely successor to nickel-hydrogen (NiH 2 ) batteries for space applications. One advantage of the NaS battery system is that the useable specific energy is two to three times that of NiH 2 batteries. This represents significant launch cost savings or increased payload mass capabilities. NaS batteries support NASA OAST's proposed Civil Space Technology Initiative goal of a factor of two improvement in spacecraft power system performance, as well as the proposed Spacecraft 2000 initiative. The NaS battery operates at between 300 and 400 °C, using liquid sodium and sulfur/polysulfide electrodes and solid ceramic electrolyte [1 – 3]. The transport of the electrode materials to the surface of the electrolyte is through wicking/capillary forces. These critical transport functions must be demonstrated under actual microgravity conditions before NaS batteries can be confidently utilized in space. For Aerospace Corporation, under contract to NASA Lewis Research Center, is currently working on the NaS battery space flight experiment definition study. The objective is to design the experiment that will demonstrate operation of the NaS battery/cell in the space environment, with particular emphasis on evaluation of microgravity effects. Experimental payload definitions have been completed and preliminary designs of the experiment have been defined.
Testing for Factor Price Equality with Unobserved Differences in Factor Quality or Productivity

We develop a method for identifying departures from relative factor price equality that is robust to unobserved variation in factor productivity. We implement this method using data on the relative wage bills of nonproduction and production workers across 170 local labor markets comprising the continental United States for 1972, 1992, and 2007. We find evidence of statistically significant differences in relative wages in all three years. These differences increase in magnitude over time and are related to industry structure in a manner that is consistent with neoclassical models of production
A computational study of physical and chemical inhibition in a perfectly stirred reactor

This paper reports a set of modeling studies that were undertaken to acquire a more detailed knowledge of combustion inhibition mechanisms. Mixtures of H2/O2/Ar reacting in the idealized perfectly stirred reactor were investigated. Three H2/O2 kinetic mechanisms were considered, differing from one another by the number of HO2 reactions included. Two physical inhibitors, Ar and N2, and one chemical inhibitor, HBr, were investigated. Additional parameters considered were pressure, equivalence ratio, inhibitor concentration and rate coefficient variation. The most effective inhibitor was HBr which acted chemically and caused substantial reduction in radical concentrations in the mixtures considered. The molecules Ar and N2 acted as physical diluents with N2, the more effective of the two due to its larger heat capacity.
Material content of the Universe: meeting summary

We have considered what might be said about the large-scale distribution of mass in the Universe and in particular whether the mean value might agree with the Einstein-de Sitter cosmological model; what might be said about the composition of the mass as a function of position, and in particular whether we can convince ourselves that exotic matter plays a significant role in some regions; and what might be said about the cosmic evolution of the mass distribution and composition. The present state of our debate is notable for the broad variety of interesting-looking clues and the lack of general agreement on how they might fit together in some general synthesis.
Model of Tellurium- and Zinc-Doped Indium Antimonide Solidification in Space

Numerical simulations were performed to determine the effect of residual microaccelerations on the distribution of dopants (Te and Zn) during solidification of InSb in space. A moving geometry model was developed and used to account for the reduction in melt size during growth. The model demonstrates that diffusion controlled segregation in doped InSb can be obtained at 10 -5 g 0 gravity for the considered growth parameters. The results for the moving geometry and semi-infinite melt domain models are compared to each other and to the analytical correlations for the case of diffusion-controlled segregation.
On a Successive Approximation Technique in Solving Some Control System Optimization Problems

Abstract It has been realized for some time that most realistic optimization problems defy analytical solutions in closed forms and that in most cases it is necessary to resort to judicious combinations of analytical and computational procedures to solve problems. For example, in many optimization problems, one is interested in obtaining structural information on optimal and “good” suboptimal policies. Very often, various analytical as well as computational approximation techniques need be employed to obtain clear understandings of structures of policy spaces. The paper discusses a successive approximation technique to construct minimizing sequences for functionals in extremal problems, and the techniques will be applied, to a class of optimization problems, given by: Min υ F(υ) = Min υ ∫ 0 1 g(u,υ)dt where du dt = h(u, v) , and where u and v are, in general, elements of Banach spaces. In Section II, B, the minimizing sequences are constructed by approximating g(u, v) by appropriate quadratic expressions with linear constraining differential equations. It is shown that under the stated conditions the functional values converge to the minimal value monotonically. In Section III, the restriction that the differential equation be linear is removed. Differential equation are approximated by appropriate linear equations and the technique of Section II, B is applied to obtain minimizing sequences. The convergence of the minimizing sequence to the solution of the original nonlinear differential equation is shown. An example is also included to illustrate some of the techniques.
Proton-Neutron Damage Correlation in Semiconductors

The results of a study program to determine a proton-neutron damage correlation in semiconductors are presented. Three approaches were undertaken: Theoretical, Empirical using data from existing literature, and Experimental. The results of the theoretical studies show that damage processes between the neutrons and protons are basically different in silicon. Damage from neutron irradiation is characterized by the effective cross sectional area of the cluster of displaced atoms and is relatively independent of the type of impurity. Damage from protons, on the other hand, is dominated by the defects involving impurities. For this reason, theoretically derived damage "cross sections" for each different type of bambarding particle must be based on different (and independent) physical properties of the semiconductor material. In the empirical study using the data from the literature, it was not possible to determine a reliable proton-neutron correlation. Spread in neutron damage data due to irradiation of different types of devices, inadequate data reporting and no data on similar type semiconductors under both neutron and proton irradiation contributed to this result. The experimental program was carried out on silicon solar cells under fission and moderated neutrons and proton energies of 48.5, 68.9, and 96.5 Mev. A proton-neutron correlation for the diffusion length damage was determined and the ratios of the proton to neutron damage varied frmn 0.6 to 4.8 depending on the proton energy and neutron spectrum.
Multiple Testing and Error Control in Gaussian Graphical Model Selection

Graphical models provide a framework for exploration of multivariate dependence patterns. The connection between graph and statistical model is made by identifying the vertices of the graph with the observed variables and translating the pattern of edges in the graph into a pattern of conditional independences that is imposed on the variables’ joint distribution. Focusing on Gaussian models, we review classical graphical models. For these models the defining conditional independences are equivalent to vanishing of certain (partial) correlation coefficients associated with individual edges that are absent from the graph. Hence, Gaussian graphical model selection can be performed by multiple testing of hypotheses about vanishing (partial) correlation coefficients. We show and exemplify how this approach allows one to perform model selection while controlling error rates for incorrect edge inclusion.
Fossil fuel prices and the economic and budgetary challenges of a small energy-importing economy: the case of Portugal

This paper examines the economic and budgetary impacts of fuel prices using a dynamic general equilibrium model of the Portuguese economy which highlights the mechanisms of endogenous growth and includes a detailed modeling of the public sector. The fuel price scenarios are based on forecasts by the US Department of Energy (DOE-US) and the International Energy Agency (IEA-OECD) and represent a wide range of projections for absolute and relative fossil fuel prices. In terms of the long term economic impact, our results suggest a 1.9 % drop in GDP in the DOE-US scenario and 1.6 % in the IEA-OECD scenario. As to the budgetary impact, higher fuel prices lead to lower tax revenues, which, coupled with a reduction in public spending, translate into lower public deficits. Accordingly, increasing fuel prices create an important policy trade off in that they can contribute to reducing the public deficit while hindering economic growth. We find that fairly strong incentives for wind energy can reduce the economic impact of fuel prices by 14.2 % in the DOE-US price scenario and 18.5 % reduction in the IEA-OECD price scenario. Finally, our results highlight the importance of public sector spending decisions and the mechanisms of endogenous growth in understanding the impact of fossil fuel prices. Indeed, a scenario of higher fuel prices would, with exogenous public decisions and exogenous economic growth assumptions, result in substantially smaller economic effects and yield adverse budgetary effects.
Scale-free networks in cell biology

A cell's behavior is a consequence of the complex interactions between its numerous constituents, such as DNA, RNA, proteins and small molecules. Cells use signaling pathways and regulatory mechanisms to coordinate multiple processes, allowing them to respond to and adapt to an ever-changing environment. The large number of components, the degree of interconnectivity and the complex control of cellular networks are becoming evident in the integrated genomic and proteomic analyses that are emerging. It is increasingly recognized that the understanding of properties that arise from whole-cell function require integrated, theoretical descriptions of the relationships between different cellular components. Recent theoretical advances allow us to describe cellular network structure with graph concepts and have revealed organizational features shared with numerous non-biological networks. We now have the opportunity to describe quantitatively a network of hundreds or thousands of interacting components. Moreover, the observed topologies of cellular networks give us clues about their evolution and how their organization influences their function and dynamic responses.
Conformational investigations of 6-EXO and 6-ENDO- methylbicyclo[3.1.0] hexan-3-one

Abstract R band (26.5–40 GHz) microwave spectra have been recorded for the common isotopic species of 6-endo-methylbicyclo[3.1.0]hexan-3-one and 6-exo-methylbicyclo[3.1.0]hexan-3-one. These spectra are shown to be consistent with a ground vibrational state boat conformation having five membered ring dihedral angles of 7.2 ± 0.3° and 20.5 ± 1.4° respectively. This information is correlated with product quantum yields obtained on photolysis of these molecules.
An investigation of supervisory control of remote manipulation

Abstract Various types and levels of computer assistance in manipulation are discussed and the requirements for modeling of supervisory control are identified. A simple supervisory control computer program for manipulator operation is described and, using results from manual control experimentation and modeling of the computer program, an estimate of system performance is given.
Beyond TCNE: new building blocks for molecule-based magnets

Several new examples of organic one-electron acceptors have been discovered to be viable and versatile alternatives to tetracyanoethylene as building blocks for the synthesis of charge-transfer salt/charge-transfer polymer molecule-based magnets. Guidelines for the identification of new acceptor candidates as well as several examples of compounds derived from these acceptors will be described. The observed magnetic properties include glassy ferromagnetism, metamagnetism and ferrimagnetism.
Base-promoted reactions in ionic liquid solvents. The Knoevenagel and Robinson annulation reactions

Abstract When used in place of classical organic solvents, ionic liquids offer a new and environmentally benign approach toward solvation in modern synthetic chemistry. Two classical named reactions, the Knoevenagel condensation and Robinson annulation, have been studied using the ionic liquid 1-hexyl-3-methyl imidazolium hexafluorophosphate, [6-mim]PF 6 as solvent. Yields for each reaction were moderate to excellent. In each system the ionic liquid was successfully recycled for reuse in subsequent reaction runs, a factor of key importance to the ‘green’ nature of solvation with ionic liquids.
(NH4)2Te2WO8: A New Polar Oxide with Second-Harmonic Generating, Ferroelectric, and Pyroelectric Properties

A new polar ammonium tungsten tellurite, (NH4)2Te2WO8, has been synthesized and structurally characterized. The material was synthesized hydrothermally, using NH4OH, WO3, and TeO2 as reagents, and structurally characterized by single-crystal X-ray diffraction. (NH4)2Te2WO8 crystallizes in the noncentrosymmetric (NCS) polar monoclinic space group P21 (No. 4) with a = 6.9716(9) A, b = 7.0279(9) A, c = 9.4593(13) A, and β = 99.188(2)°. The material exhibits a two-dimensional structure consisting of WO6 octahedra connected to TeO4 polyhedra. Both the W6+ and the Te4+ cations are in asymmetric coordination environments attributable to second-order Jahn−Teller (SOJT) effects. (NH4)2Te2WO8 is NCS; thus second-harmonic generation (SHG) measurements were performed. SHG experiments, using 1064 nm radiation, revealed an efficiency of approximately 250 × α-SiO2. As (NH4)2Te2WO8 is also polar, ferroelectric and pyroelectric measurements were performed. A ferroelectric hysteresis loop (polarization vs electric field) w...
An experimental method for making spectral emittance and surface temperature measurements of opaque surfaces

Abstract An experimental procedure has been developed to make spectral emittance and temperature measurements. The spectral emittance of an object is calculated using measurements of the spectral emissive power and of the surface temperature of the object obtained using a Fourier transform infrared (FTIR) spectrometer. A calibration procedure is described in detail which accounts for the temperature dependence of the detector. The methods used to extract the spectral emissive power and surface temperature from measured infrared spectra were validated using a blackbody radiator at known temperatures. The average error in the measured spectral emittance was 2.1% and the average difference between the temperature inferred from the recorded spectra and the temperature indicated on the blackbody radiator was 1.2%. The method was used to measure the spectral emittance of oxidized copper at various temperatures.
Absence of Chiral Fermions in the Eichten--Preskill Model

Abstract The model proposed by Eichten and Preskill for obtaining theories with chiral fermions from the lattice is shown to undergo spontaneous symmetry breaking. In addition, the fermions appear be to Dirac-like everywhere in the phase diagram with no room for undoubled Weyl fermions. The phase diagram of a closely related Higgs-Yukawa model is similar to that of the Smit-Swift model, which also does not give rise to chiral fermions. These results cast serious doubts on the original scenario for the emergence of chiral fermions.
How Informative Are Value‐at‐Risk Disclosures?

Value at Risk (VAR), a measure of the dollar amount of potential loss from adverse market moves, has become a standard benchmark for measuring financial risk. Spurred by regulators and competitive pressures, more institutions are reporting VAR numbers in annual and quarterly financial reports. To provide preliminary evidence on the informativeness of these new disclosures, I investigate the relation between the trading VAR disclosed by a small sample of U.S. commercial banks and the subsequent variability of their trading revenues. The empirical results suggest that VAR disclosures are informative in that they predict the variability of trading revenues. Thus, analysts and investors can use VAR disclosures to compare the risk profiles of banks' trading portfolios.
Enzymatic Synthesis of β-Hydroxy-α-amino Acids Based on Recombinant d- and l-Threonine Aldolases

To exploit the enzymatic method for the synthesis of β-hydroxy-α-amino acids, the genes coding for the Escherichia coli l-threonine aldolase (LTA; EC 2.1.2.1) and Xanthomonus oryzae d-threonine aldolase (DTA) were cloned and overexpressed in E. coli through primer-directed polymerase chain reactions. The purified recombinant enzymes were studied with respect to kinetics, specificity, stability, additive requirement, temperature profile, and pH dependency. DTA requires magnesium ion as a cofactor, while LTA needs no metal ions. These enzymes work well in the presence of DMSO with concentration up to 40%, and DMSO-induced rate acceleration of LTA-catalyzed reaction was observed. Both enzymes use pyridoxal phosphate coenzyme to activate glycine to react with a wide range of aldehydes. LTA gave erythro-β-hydroxy-α-l-amino acids with aliphatic aldehydes and the threo isomer with aromatic aldehydes as kinetically controlled products. On the other hand, DTA formed threo-β-hydroxy-α-d-amino acids as kinetically c...
Nova Geminorum 1912 and the origin of the idea of gravitational lensing

Einstein's early calculations of gravitational lensing, contained in a scratch notebook and dated to the spring of 1912, are reexamined. A hitherto unknown letter by Einstein suggests that he entertained the idea of explaining the phenomenon of new stars by gravitational lensing in the fall of 1915 much more seriously than was previously assumed. A reexamination of the relevant calculations by Einstein shows that, indeed, at least some of them most likely date from early October 1915. But in support of earlier historical interpretation of Einstein's notes, it is argued that the appearance of Nova Geminorum 1912 (DN Gem) in March 1912 may, in fact, provide a relevant context and motivation for Einstein's lensing calculations on the occasion of his first meeting with Erwin Freundlich during a visit in Berlin in April 1912. We also comment on the significance of Einstein's consideration of gravitational lensing in the fall of 1915 for the reconstruction of Einstein's final steps in his path towards general relativity.
Optimal Management of Malignant Epidural Spinal Cord Compression

Malignant epidural spinal cord compression (MESCC) is a common neurologic complication of cancer. MESCC is a medical emergency that needs rapid diagnosis and treatment to prevent undergo emergent evaluation including magnetic resonance imaging of the entire spine. If MESCC is diagnosed, corticosteroids should be administered. Simultaneously, spine surgery and oncology teams should be immediately consulted. If indicated, patients should undergo maximal tumor resection and stabilization, followed by postoperative radiotherapy. Emerging treatment options such as stereotactic radiosurgery and vertebroplasty may be able to provide some symptomatic relief for patients who are not surgical candidates.