cssi/SciSciGPT-SciSciNet huggingface dataset:
NEW SIGNATURES AND SOURCES FOR THE DETECTION OF WIMP DARK MATTER IN THE SOLAR SYSTEM

Abstract I first outline new results on the angular modulation of WIMP dark matter scattering on targets in terrestrial laboratories, based on our uncertainties of the WIMP halo distribution, I then outline an exciting new result which indicates that for the high end of allowed SUSY WIMP scattering cross sections there exists a new distribution of WIMP dark matter in our solar system which could produce a dramatically different signal from halo WIMP dark matter in terrestrial detectors.
Natural Language Applications and Technologies

Every technical field can be characterized in at least two ways: (1) by the various applications accomplished in that field and (2) by the underlying technologies implementing these applications. It is equally true that new applications depend new technologies or extension of old ones. The purpose of this paper is to show how this thinking can be productively applied to the field of NATURAL LANGUAGE PROCESSING. My hope is that the discussions of language applications, language technologies, and their interrelationships, will make practical systems in this area appear more promising and achievable than they might have been previously.
Microwave Ferroelectric Devices

Control of reactance in microwave circuits, devices, and systems is a common method by which the response of a microwave circuit such as a filter, resonator, or phase shifter can be tuned. Devices based on a class of voltagedependent non-linear dielectrics known as ferroelectrics provide an alternative to semiconductor varactor diodes and ferrimagnetic components, which are the most common devices of this type. This article describes microwave devices that exploit the variation of the ferroelectric's permittivity with applied DC electric field. The main feature of these “tunable” microwave devices is the change of their capacitance, impedance, or phase velocity. We will describe varactors, oscillators, tunable filters, and phase shifting devices. Keywords: varactors; oscillators; tunable filters; ferroelectrics; microwave circuits; phase shifting devices; superconductors
An Intensified Photodiode Array Detector for Space Applications

The Hopkins Ultraviolet Telescope (HUT) is a general purpose moderate resolution spectrograph which is now being constructed for launch on the Space Shuttle. The instrument contains a Rowland spectrograph, which is located at the prime focus of a 0.9-m f/2 parabola. A description is given of the progress which has been made in the development of a flight detector for HUT. The detector developed is an intensified photodiode array. The image intensifier part of the detector contains two 25-mm 80:1, 12-micron pore microchannel plates (PCPs). A thin layer of CsI deposited on the front surface of the first microchannel plate has the objective to increase the quantum efficiency of the detector below 1850 A. The detector system utilizes a spectrometer processor (SP) which is based upon a bit-sliced microprocessor. The current status of the HUT detector system is discussed, and aspects of performance are evaluated. It is felt that the developed system will meet or exceed the design requirements.
Digestion of DNA with Restriction Endonucleases

Restriction endonucleases recognize short DNA sequences and cleave double-stranded DNA at specific sites within or adjacent to the recognition sequences. Restriction endonuclease cleavage of DNA into discrete fragments is one of the most basic procedures in molecular biology. The first method presented in this unit is the cleavage of a single DNA sample with a single restriction endonuclease. A number of common applications of this technique are also described. These include digesting a given DNA sample with more than one endonuclease, digesting multiple DNA samples with the same endonuclease, and partially digesting DNA such that cleavage only occurs at a subset of the restriction sites. A protocol for methylating specific DNA sequences and protecting them from restriction endonuclease cleavage is also presented. A collection of tables describing restriction endonucleases and their properties (including information about recognition sequences, types of termini produced, buffer conditions, and conditions for thermal inactivation) is given at the end of the unit.
Topology control using distributed power management algorithm for mobile ad hoc networks

We propose a distributed power management algorithm that decides on an optimum coverage area for individual node to preserve network connectivity, reduce interference thus improve network performance with changing environment and network topology. In order to be strongly connected in the network, a node may increase its power indiscriminately causing interference. Since interference is one of the major problems in wireless network, the proposed algorithm will co-operatively reduce inter-node interference in the network. Uni-directional links are also a major source of interference as most of the routing protocol only utilizes bi-directional links. So, the algorithm will attempt to prevent such links or if required convert them into bi-directional links. We will show that the algorithm provides strongly connected and more reliable network over dynamic physical channel modeled by log-distance path loss model, log-normal shadowing model and rayleigh fading model. We will show that the proposed algorithm stabilizes node connectivity over the dynamic network and environment and even, to a certain extent, prevent node from being completely disconnected from the network. Further, it reduces interference and improves network performance.
A method for measuring the Néel relaxation time in a frozen ferrofluid

We report a novel method of determining the average Neel relaxation time and its temperature dependence by calculating derivatives of the measured time dependence of temperature for a frozen ferrofluid exposed to an alternating magnetic field. The ferrofluid, composed of dextran-coated Fe3O4 nanoparticles (diameter 13.7 nm ± 4.7 nm), was synthesized via wet chemical precipitation and characterized by x-ray diffraction and transmission electron microscopy. An alternating magnetic field of constant amplitude ( H0=20 kA/m) driven at frequencies of 171 kHz, 232 kHz, and 343 kHz was used to determine the temperature dependent magnetic energy absorption rate in the temperature range from 160 K to 210 K. We found that the specific absorption rate of the ferrofluid decreased monotonically with temperature over this range at the given frequencies. From these measured data, we determined the temperature dependence of the Neel relaxation time and estimate a room-temperature magnetocrystalline anisotropy constant of ...
Functional encryption: definitions and challenges

We initiate the formal study of functional encryption by giving precise definitions of the concept and its security. Roughly speaking, functional encryption supports restricted secret keys that enable a key holder to learn a specific function of encrypted data, but learn nothing else about the data. For example, given an encrypted program the secret key may enable the key holder to learn the output of the program on a specific input without learning anything else about the program. We show that defining security for functional encryption is non-trivial. First, we show that a natural game-based definition is inadequate for some functionalities. We then present a natural simulation-based definition and show that it (provably) cannot be satisfied in the standard model, but can be satisfied in the random oracle model. We show how to map many existing concepts to our formalization of functional encryption and conclude with several interesting open problems in this young area.
The Interplay of Cluster and Galaxy Evolution

We review here the interplay of cluster and galaxy evolution. As a case study, we consider the Butcher-Oemler effect and propose that it is the result of the changing rate of cluster merger events in a hierarchical universe. This case study highlights the need for new catalogs of clusters and groups that possess quantified morphologies. We present such a sample here, namely the Sloan Digital Sky Survey (SDSS) C4 Catalog, which has been objectively-selected from the SDSS spectroscopic galaxy sample. We outline here the C4 algorithm and present first results based on the SDSS Early Data Release, including an X-ray luminosity-velocity dispersion (Lx-συ) scaling relationship (as a function of cluster morphology) and the density-SFR relation of galaxies within C4 clusters (Gomez et al., 2003). We also discuss the merger of Coma and the NGC4839 group and its effect on the galaxy populations in these systems. We finish with a brief discussion of a new sample of Hδ-selected galaxies (i.e., k + a, post-starburst galaxies) obtained from the SDSS spectroscopic survey.
PASSCoDe: Parallel ASynchronous Stochastic dual Co-ordinate Descent

Stochastic Dual Coordinate Descent (DCD) is one of the most efficient ways to solve the family of l2-regularized empirical risk minimization problems, including linear SVM, logistic regression, and many others. The vanilla implementation of DCD is quite slow; however, by maintaining primal variables while updating dual variables, the time complexity of DCD can be significantly reduced. Such a strategy forms the core algorithm in the widely-used LIBLINEAR package. In this paper, we parallelize the DCD algorithms in LIBLINEAR. In recent research, several synchronized parallel DCD algorithms have been proposed, however, they fail to achieve good speedup in the shared memory multi-core setting. In this paper, we propose a family of parallel asynchronous stochastic dual coordinate descent algorithms (PASSCoDe). Each thread repeatedly selects a random dual variable and conducts coordinate updates using the primal variables that are stored in the shared memory. We analyze the convergence properties of DCD when different locking/atomic mechanisms are applied. For implementation with atomic operations, we show linear convergence under mild conditions. For implementation without any atomic operations or locking, we present a novel error analysis for PASSCoDe under the multi-core environment, showing that the converged solution is the exact solution for a primal problem with a perturbed regularizer. Experimental results show that our methods are much faster than previous parallel coordinate descent solvers.
Cash Social Transfers, Direct Taxes, and Income Distribution in Late Socialism

The author analyzes the impact of direct taxes and cash social transfers on income distribution in Bulgaria, Czechoslovakia, Hungary, Poland and Yugoslavia in the years before the collapse of communism. He contrasts the results for socialist and market economies. Cash social transfers accounted for about a fifth of gross income, a proportion comparable with that in developed welfare economies. Generally, cash transfers were unrelated to income in socialist countries, in marked contrast with market economies, where such transfers go mainly to low income households. Direct taxes played almost no role in income redistribution. They were small - 1 to 2 percent of gross income, except in Hungary - and proportional to income. Most taxes were paid by enterprises, as payroll taxes, and most workers were unaware of the taxation and that public spending could not permanently exceed public revenues from taxation. In socialist countries, social support was built into the system through full employment guarantees, state run pension schemes, and free public education and health care. The only explicit policy toward poverty involved alcoholics, handicapped people, and other special categories. This system is being replaced by a market system in which the labor market is key and those who cannot earn enough must be supported by the state. To counteract increasing income disparities, social transfers must be focussed more on the poor. Eastern European states are ill prepared for this role. They have no experience in identifying the needy and targeting support to them. The question is, toward which world of welfare capitalism are the formerly socialist countries likely to evolve? The author contends that the Central European countries will probably evolve toward the corporatist model of continental Europe. Capitalist countries in Europe tend to have large social transfers that are often related to previous earnings, so they have relatively limited roles in income distribution. Transfers are closer to social insurance than to social assistance. The evolution of more agricultural Balkan countries and the Slavic republics of the former Soviet Union is more difficult to predict. Poorer and more agriculture based countries are generally less able to administer welfare schemes, gauge individual incomes, deliver social support - and their finances may be even more strained than those of their Central European counterparts.
Optimal Bacon-Shor codes

We study the performance of Bacon-Shor codes, quantum subsystem codes which are well suited for applications to fault-tolerant quantum memory because the error syndrome can be extracted by performing two-qubit measurements. Assuming independent noise, we find the optimal block size in terms of the bit-flip error probability pX and the phase error probability pZ, and determine how the probability of a logical error depends on pX and pZ. We show that a single Bacon-Shor code block, used by itself without concatenation, can provide very effective protection against logical errors if the noise is highly biased (pZ/pX > 1) and the physical error rate pZ is a few percent or below. We also derive an upper bound on the logical error rate for the case where the syndrome data is noisy.
Evidence against global attention filters selective for absolute bar-orientation in human vision

The finding that an item of type A pops out from an array of distractors of type B typically is taken to support the inference that human vision contains a neural mechanism that is activated by items of type A but not by items of type B. Such a mechanism might be expected to yield a neural image in which items of type A produce high activation and items of type B low (or zero) activation. Access to such a neural image might further be expected to enable accurate estimation of the centroid of an ensemble of items of type A intermixed with to-be-ignored items of type B. Here, it is shown that as the number of items in stimulus displays is increased, performance in estimating the centroids of horizontal (vertical) items amid vertical (horizontal) distractors degrades much more quickly and dramatically than does performance in estimating the centroids of white (black) items among black (white) distractors. Together with previous findings, these results suggest that, although human vision does possess bottom-up neural mechanisms sensitive to abrupt local changes in bar-orientation, and although human vision does possess and utilize top-down global attention filters capable of selecting multiple items of one brightness or of one color from among others, it cannot use a top-down global attention filter capable of selecting multiple bars of a given absolute orientation and filtering bars of the opposite orientation in a centroid task.
Noncommutative Mechanics, Landau Levels, Twistors, and Yang–Mills Amplitudes

These lectures fall into two distinct, although tenuously related, parts. The first part is about fuzzy and noncommutative spaces, and particle mechanics on such spaces, in other words, noncommutative mechanics. The second part is a discussion/review of the use of twistors in calculating Yang-Mills amplitudes. The point of connection between these two topics is in the realization of holomorphic maps as the lowest Landau level wave functions, or as wave functions of the Hilbert space used for the fuzzy version of the two-sphere.
Bt Corn and the Monarch Butterfly: Research Update

Publisher Summary This chapter discusses the effects of Bacillus thuringiensis ( Bt ) corn on the monarch butterfly, Danaus plexippus . In a laboratory investigation conducted by Losey et al. , young monarch larvae, which were given no choice but to feed on milkweed, Asclepias curassavica , leaves dusted with pollen from a Bt corn hybrid ate less, grew more slowly, and had a significantly higher mortality rate than larvae feeding on leaves dusted with nontransgenic pollen. The amount of pollen dusted onto the milkweed leaves in the Losey et al. study was not quantified, and as a result, the dose of Bt protein consumed by the larvae could not be quantified. To formulate a quantitative risk assessment, the level of toxicity must first be determined. Although toxicity of Bt pollen and the toxins expressed by pollen can be clearly documented and could represent a hazard, the risk to monarch populations from exposure to Bt corn pollen is also a function of exposure. For monarchs to be exposed and potentially affected by corn pollen, larval development must coincide with corn anthesis. Exposure to the pollen, may be longer depending on the duration of pollen availability on milkweed and the rate of Bt protein degradation. Another important factor in assessing exposure of monarch larvae to Bt pollen is milkweed distribution. Behavior of monarch larvae and adults also can influence exposure to Bt pollen.
Diverse Applications of Nitrones for the Synthesis of Heterocyclic Compounds

Although best known for their [3+2]-dipolar cycloaddition reactivity and use in the preparation of isoxazolines and isoxazolidines, nitrones are versatile reagents that undergo a variety of transformations for the synthesis of a diverse array of heterocyclic compounds. The breadth of heterocycle synthesis using nitrone reagents includes: 1) stepwise [3+3]-cycloaddition reactions of nitrones with vinyl diazoacetates, transition-metal-coordinated cycloisomerization intermediates, trimethylene methanes, and cyclopropane diesters to form dihydro- and tetrahydro-1,2-oxazines; 2) internal redox cyclization reactions of alkyne-tethered nitrones to provide access to azabicyclooctanes, isoindoles, aminoindanones, and isoquinolones; 3) electrocyclizations of in situ generated N-allenylnitrones to form pyridines and azetidine-N-oxides, as well as metal-catalyzed cyclizations and rearrangements of nitrones to form azepine-N-oxides, spirocyclic isoxazolines, and α,β-epoxyimines; and 4) the use of [3+2]-cycloaddition reactions of nitrones to trigger cascade reactions for the formation of tetrahydrooxazepines, dihydrocarbazoles, and benzoindolizines. This Focus Review aims to highlight these diverse applications of nitrones for the synthesis of heterocycles to emphasize the broad utility of these reactive intermediates and to inspire their further development as important synthons beyond the scope of traditional [3+2]-dipolar cycloaddition reactions.
Reflectance hashing for material recognition

We introduce a novel method for using reflectance to identify materials. Reflectance offers a unique signature of the material but is challenging to measure and use for recognizing materials due to its high-dimensionality. In this work, one-shot reflectance of a material surface which we refer to as a reflectance disk is capturing using a unique optical camera. The pixel coordinates of these reflectance disks correspond to the surface viewing angles. The reflectance has class-specific stucture and angular gradients computed in this reflectance space reveal the material class. These reflectance disks encode discriminative information for efficient and accurate material recognition. We introduce a framework called reflectance hashing that models the reflectance disks with dictionary learning and binary hashing. We demonstrate the effectiveness of reflectance hashing for material recognition with a number of real-world materials.
The middle-income trap turns ten

Since we introduced the term “middle-income trap” in 2006, it has become popular among policy makers and researchers. In May 2015, a search of Google Scholar returned more than 3,000 articles including the term and about 300 articles with the term in the title. This paper provides a (non-exhaustive) survey of this literature. The paper then discusses what, in retrospect, we missed when we coined the term. Today, based on developments in East Asia, Latin America, and Central Europe during the past decade, we would have paid more attention to demographic factors, entrepreneurship, and external institutional anchors. We would also make it clearer that to us, the term was as much the absence of a satisfactory theory that could inform development policy in middle-income economies as the articulation of a development phenomenon. Three-quarters of the people in the world now live in middle-income economies, but economists have yet to provide a reliable theory of growth to help policy makers navigate the transition from middle- to high-income status. Hybrids of the Solow-Swan and Lucas-Romer models are not unhelpful, but they are poor substitutes for a well-constructed growth framework.
The Changing Blazhko Effect of XZ Cygni

New CCD photometry has been obtained for the RR Lyrae variable star XZ Cygni. An analysis of old and new photometry confirms earlier results that XZ Cyg exhibits the Blazhko effect and that its Blazhko period has changed over time. These changes in the Blazhko period are anticorrelated with observed changes in the primary period of XZ Cyg. During the first half of the 20th century, XZ Cyg had a Blazhko period of approximately 57.4 days. Beginning in 1965, its primary period underwent a steep decline in several steps. Coincidentally, its Blazhko period increased to about 58.5 days. In 1979, the primary period suddenly increased again. After an interval in which the Blazhko effect was small, the Blazhko effect reestablished itself, with a period of approximately 57.5 days. When its Blazhko period is near 57.5 days, XZ Cyg has also shown a tertiary period of 41.6 days. We confirm that there is evidence for a longer 3540 day period in photometry obtained during the first half of the 20th century. XZ Cyg is compared with three other RR Lyrae stars that also appear to show changing Blazhko periods. The observed changes in the length of the Blazhko period of XZ Cyg constrain possible explanations for the Blazhko effect. In particular, they argue against any theoretical explanation that requires that the Blazhko period be exactly equal, or directly proportional, to the rotation period of the star.
Assessing the intensity of sports rivalries using data from secondary market transactions.

Assessing the intensity of college football rivalries is an annual exercise of sports columnists. Fan polling, average ticket price, and even the bad behaviors of athletes have been used to quantif...
Retinal damage produced by intraocular fiber optic light.

We exposed the maculas of owl monkey eyes to light from an intraocular fiber optic light source similar to that used for human pars plana vitrectomy. Retinal irradiance was calculated at 0.22 W/cm2. Eyes were exposed for time intervals ranging from 30 minutes to five minutes and were observed after light treatment by fundus photography and fluorescein angiography. Tissue was obtained for light and electron microscopy by animal killing at one hour, 24 hours, one week, and four weeks. Fundus lesions were seen ophthalmoscopically as early as five hours following 30 minutes of light exposure. Significant damage to the photoreceptor layer and less damage to the pigment epithelium was present by light and electron microscopy as early as one hour after 30 minutes of light exposure. By one month complete loss of photoreceptors with Muller cell junctions between inner retina and flattened abnormal retinal pigment epithelium cells was observed. Fluorescein angiography revealed significant staining of the pigment epithelium and outer retina 24 hours after 30 minutes of light exposure. No leakage from retinal vessels occurred. At one month following light treatment, transmission of choroidal fluorescein through window defects in the pigment epithelium was present with no retinal staining. The threshold for ophthalmoscopically visible fundus lesions in this study was 15 minutes of light exposure. Ten minutes of light treatment was the threshold for microscopic changes. Short light exposures damaged the outer retina and spared the pigment epithelium. Removing a substantial amount of the infrared light from our light source did not protect the retina from damage. Removal of light between 400 and 500 nm is probably more helpful in protecting the retina. Intermittent light exposure of the retina seemed as harmful as uninterrupted illumination for the same cumulative period of time. We speculate that the retinal damage caused by intraocular fiber optic light has primarily a photic mechanism. Damage to the retinal pigment epithelium may be secondary to outer retinal damage. The present levels of intraocular light used for human pars plana vitrectomy are probably safe in most instances. Lengthy preretinal membrane stripping procedures during vitrectomy, however, may pose a threat of light damage to the retina. This damage must be appreciated as continued efforts are made to produce brighter sources of intraocular light for human pars plana vitrectomy.
Sequential N-Arylation of Primary Amines as a Route To Alkyldiarylamines

The synthesis of unsymmetrical alkyldiarylamines from a primary amine and two aryl bromides is described. A catalyst system composed of Pd(OAc)2/(rac)-BINAP is used to prepare an alkylarylamine (1) from a primary amine and aryl bromide. The palladium-catalyzed arylation of 1, by means of a different catalyst system, affords an alkyldiarylamine. The efficiency of each catalyst for the second step depends on the electronic nature of the substrates. This method has reasonable generality and compatiblity with base-sensitive functional groups.
Transformation: From Teacher-Centered to Student-Centered Engineering Education

We compare and contrast teacher-centered and student-centered paradigms of engineering education. We identify the following seven roles for teachers wishing to adopt a student-centered paradigm: 1) model thinking/processing skills, 2) identify students' cognitive development, 3) develop questions that facilitate exploration/growth, 4) introduce visual tools to aid establishing connections, 5) provide group learning settings, 6) use analogies and metaphors, and 7) provide a “no-risk” student feedback channel for information. Several case studies for different subjects and from different institutions are presented. Our results indicate a student-centered model is most effective when coupled with academic depth and experience in the subject matter.
The costs and underappreciated consequences of research misconduct: a case study.

Fallout from scientific misconduct can be pervasive. From the broadest perspective, the public, current and future patients, funding agencies, and even the course of research may be adversely affected by scientific misconduct. At the local level. members of the perpetrator’s laboratory, colleagues, trainees, and the financial resources and reputation of the home institution may become tainted. The costs associated with these acts are substantial. This article will present a model we have developed to estimate the monetary costs of scientific misconduct. Estimates are based on a case that occurred at our institution, the Roswell Park Cancer Institute, which is a National Cancer Institute–designated Comprehensive Cancer Center located in the United States. Our experiences will likely not be wholly representative of other institutions, but we feel could be instructional and should serve as a guide in the calculation of costs at other institutions. Scientific misconduct is defined by the
Microscopic approach to the nucleon-nucleon effective interaction and nucleon-nucleon scattering in symmetric and isospin-asymmetric nuclear matter

After reviewing our microscopic approach to nuclear and neutron-rich matter, we focus on how nucleon-nucleon scattering is impacted by the presence of a dense hadronic medium, with special emphasis on the case where neutron and proton densities are different. We discuss in detail medium and isospin asymmetry effects on the total elastic cross section and the mean free path of a neutron or a proton in isospin-asymmetric nuclear matter. We point out that in-medium cross sections play an important role in heavy-ion simulations aimed at extracting constraints on the symmetry potential. We argue that medium and isospin dependence of microscopic cross sections are the result of a complex balance among various effects, and cannot be simulated with a simple phenomenological model.
Total synthesis of the lycopodium alkaloid (+)-serratezomine A.

The first total synthesis of (+)-serratezomine A is described. Key aspects of the synthesis include (a) the first deployment of free-radical-mediated vinyl amination (an intramolecular alkyne aminostannation) in a complex target synthesis, (b) the use of a β-stannyl enamine as the lynchpin for convergent assembly of the natural product backbone, (c) the use of an oxidative allylation promoted by cerium(IV) (CAN) to establish the all-carbon quaternary chiral center with the proper configuration, and (d) an intramolecular substitution reaction to form the sensitive bridging lactone. Overall, 15 steps (longest linear sequence) are required to prepare the natural product from a commercially available aldehyde, and assembly of the contiguous array of six stereocenters is accomplished with high stereocontrol.
Goiter on an iodine-free diet grown by hydroponics, and excluding any goiter noxa.

VARIOUS workers have experienced difficulty in finding foodstuffs sufficiently low in iodine to produce goiter. This fact has helped to revive the germ (“virus”) theory of goiter (1). It seemed of interest to produce goiter in a goiter-free region with precautions against introducing any hypothetical virus. In order to obtain food free from iodine and virus it was grown by hydroponics in a disinfected greenhouse. According to Frazier (2) goiter is not endemic in this region. Furthermore we did not allow any person or animal with goiter inside the greenhouse. The floor was freshly coated with asphalt and the whole interior, including tanks and window panes, sprayed with 5 per cent DDT and 1 per cent cresol in kerosene. The greenhouse is 25 miles from the nearest city and the water used was rain caught on a glass roof and filtered through amberlite IR4 freshly activated with aluminum ions which would remove any “goiter germ.” The reagent chemicals were dissolved in water at pH 10 and filtered through freshl...
Effects of Implicit Preconditioners on Solution Acceleration Schemes in Cfd

Several solution acceleration techniques, used to obtain steady state CFD solutions as quickly as possible, are applied to an implicit, upwind Euler solver to evaluate their effectiveness. The implicit system is solved using either ADI or ILU and the solution acceleration techniques evaluated are quasi-Newton iteration, Jacobian freezing, multigrid and GMRES. ILU is a better preconditioner than ADI because it can use larger time steps. Adding GMRES does not always improve the convergence. However, GMRES preconditioned with ILU and multigrid can take advantage of Jacobian freezing to produce an efficient scheme that is relatively independent of grid size and grid quality.
Capacity of a class of symmetric SIMO Gaussian interference channels within O(1)

The N +1 user, 1×N single input multiple output (SIMO) Gaussian interference channel where each transmitter has a single antenna and each receiver has N antennas is studied. The symmetric capacity within O(1) is characterized for the symmetric case where all direct links have the same signal-to-noise ratio (SNR) and all undesired links have the same interference-to-noise ratio (INR). The gap to the exact capacity is a constant which is independent of SNR and INR. On the achievability side, an interesting conclusion is that the generalized degrees of freedom (GDOF) regime where treating interference as noise is found to be optimal in the 2 user interference channel, does not appear in the N + 1 user, 1 × N SIMO case. On the converse side, new multi-user outer bounds emerge out of this work that do not follow directly from the 2 user case. We also provide an outer bound on the capacity region of the 3 user SIMO Gaussian interference channel with 2 antennas at each receiver. This outer bound directly leads to the capacity region of this channel if the channel vectors satisfy certain conditions.
The Thermal Evolution following a Superburst on an Accreting Neutron Star

Superbursts are very energetic type I X-ray bursts discovered in recent years by long-term monitoring of X-ray bursters and are believed to be due to unstable ignition of carbon in the deep ocean of the neutron star. In this Letter, we follow the thermal evolution of the surface layers as they cool following the burst. The resulting light curves agree very well with observations for layer masses in the range 1025-1026 g expected from ignition calculations and for an energy release 1017 ergs g-1 during the flash. We show that at late times the cooling flux from the layer decays as a power law F ∝ t-4/3, giving timescales for quenching of normal type I bursting of weeks, in good agreement with observational limits. We show that simultaneous modeling of superburst light curves and quenching times promises to constrain both the thickness of the fuel layer and the energy deposited.
Van Hove excitons and high-Tc superconductivity V: Electron-phonon interaction

Abstract A model is developed for electron-phonon interaction in the new superconducting oxides, showing that the system is nearly unstable with respect to a charge density wave, but that weak interlayer coupling generally prevents the establishment of true long-range order. It is shown that the associated mode softening produces a significant Tc enhancement, but probably not large enough to fully account for the experimental results. Suggestions are made for an additional coupling mechanism, probably associated with fluctuations into the ordered phase.
The effects of electronic coupling and solvent broadening on the intervalent electron transfer of a centrosymmetric mixed-valence complex

Abstract A three-dimensional nuclear coordinate representation of the intervalent electron transfer processes occurring in the trinuclear mixed-valence complex, [(NC) 5 Fe(II)CNPt(IV)(NH 3 ) 4 NCFe(II)(CN) 5 ] 4− , is discussed in terms of the degree of coupling between electronic states. The related dinuclear complex, (NC) 5 Fe(II)CNPt(IV)(NH 3 ) 5 , has been synthesized and characterized by UV–vis and IR absorption spectroscopies, cyclic voltammetry, resonance Raman spectroscopy, and single crystal X-ray diffraction. The visible absorption spectra and time-dependent resonance Raman intensity analyses of the two complexes are compared with regard to the amount of electronic coupling in the trinuclear complex. The absorption spectrum of the trinuclear complex has been fit to a model, which includes a solvent broadening parameter. Based on this fit, the total reorganization energy of the photoinduced intervalent electron transfer has been calculated to be approximately 75% outer sphere.
Ethical issues in biomedical publications

Peer-reviewed biomedical journals are expected to publish accurate and important information. In the process, numerous ethical issues may arise from within both the editorial and research communities. This paper will focus on four general ethical issues-authorship, peer review, duplicate or repetitive publication, and conflict of interest. Issues of authorship include multiple authorship, misconduct among coauthors, guest and honorary authorship, order of authorship, and credit for those not qualifying for authorship. Peer review attempts to ensure that what is published is valid. Peer review ethical issues include confidentiality of the manuscript, potential editor and reviewer bias, and conflict of interest on the part of the reviewer. Duplicate or repetitive publication, in which the same information is reported two or more times, can damage a journal's reputation for publishing new and important information and can waste its resources. Conflicts of interest, in which financial and personal considerations may affect the investigator's personal judgment, can seriously damage the integrity of the author and of the journal. Increased awareness of these ethical issues should stimulate everyone to take an active role in promulgating and enforcing the highest ethical standards in biomedical publications.
A review of some recent studies on mechanisms of pyrolysis of polysaccharides

Abstract In seeking to gain a better understanding of the pyrolysis of polysaccharides, the pyrolytic behavior of a variety of naturally occurring and synthetic polysaccharides has been studied. Among the former were various glucans containing different linkage types, and for the latter, synthetic polymers were produced by thermal polymerization of a glucoside and of a xyloside. The study has focused on the effects which linkage types and inorganic additives have on pyrolytic pathways, with emphasis on the chemical mechanisms involved in the formation of one-, two- and three-carbon products, specifically glycolaldehyde, acetol, acetic acid, and formic acid. These compounds are the major non-aqueous components of the −60° condensate of the vacuum pyrolysate after removal of tar by room temperature condensation.13C labels in synthetic glucans were used to reveal the origins of these compounds. In general, the results show that each compound is formed by more than one mechanism. Specifically, glycolaldehyde derives mostly from C-1 and C-2 of the glucose monomers, with C-5 and C-6 also contributing significantly. Acetol and acetic acid derive mostly from contiguous carbons that include a terminal carbon (C-1 or C-6), most often C-6, appearing as the methyl carbon. About half of the formic acid arises from C-1. Some mechanisms derived from solution chemistry are proposed.
Palladium-catalyzed borylation of aryldiazonium tetrafluoroborate salts. A new synthesis of arylboronic esters

Abstract The first synthesis of arylboronic esters via the coupling of bis(pinacolato)diboron with easily prepared aryldiazonium tetrafluoroborate salts is reported. The palladium-catalyzed borylation reaction proceeds efficiently under mild reaction conditions in the absence of a base to afford various functionalized arylboronic esters in moderate to high yields.
Improved Methods for Large Scale Structural Synthesis

Abstract : This report describes two potential improvements in techniques for large scale structural synthesis. One involves a method for control of oscillation found to occur in many optimization procedures. The other is a new primal mathematical programming algorithm. The central idea for oscillation control is the use of the gradients of a potentially active constraint set to prevent serious violation of one of the set when a move is made considering only the active constraints. The mathematical programming procedure uses an improved feasible direction finding formulation. Results of numerical experiments using these methods on two classical ten bar truss examples are very encouraging. Serious oscillations found to occur in some optimality criteria procedures were eliminated in all cases tested. The mathematical programming method was found to be comparable in effectiveness to the optimality criteria procedures on these problems. Further research is required to refine these methods and substantiate the initial successes. (Author)
Real-Time Attitude-Independent Three-Axis Magnetometer Calibration

In this paper new real-time approaches for three-axis magnetometer sensor calibration are derived. These approaches rely on a conversion of the magnetometer-body and geomagnetic-reference vectors into an attitude independent observation by using scalar checking. The goal of the full calibration problem involves the determination of the magnetometer bias vector, scale factors and non-orthogonality corrections. Although the actual solution to this full calibration problem involves the minimization of a quartic loss function, the problem can be converted into a quadratic loss function by a centering approximation. This leads to a simple batch linear least squares solution. In this paper we develop alternative real-time algorithms based on both the extended Kalman filter and Unscented filter. With these real-time algorithms, a full magnetometer calibration can now be performed on-orbit during typical spacecraft mission-mode operations. Simulation results indicate that both algorithms provide accurate integer resolution in real time, but the Unscented filter is more robust to large initial condition errors than the extended Kalman filter. The algorithms are also tested using actual data from the Transition Region and Coronal Explorer (TRACE).
Endogenous voting weights for elected representatives and redistricting

This paper analyzes the merits of a novel method of eliminating the power of a gerrymanderer that involves an endogenous weighting system for elected representatives. This endogenous weighting system ties the voting weight of elected representatives in the legislature to the share of the voters who voted for that representative’s party and to the share of representatives elected from that party. If the weights are set correctly, it can be shown in the simple voting model of Gilligan and Matsusaka (Public Choice 100:65–84, 1999) that redistricting has no influence on the policy passed by the legislature. In effect, the endogenous weighting system converts a single-member plurality political system into one with proportional representation.
Nonphysiological (functional) unilateral motor and sensory syndromes involve the left more often than the right body.

We studied the prevalence of left versus right side involvements in nonphysiological syndromes for the following reasons: 1) prior studies have produced conflicting results; 2) prior studies occured before the availability of current neurodiagnostic techniques such as computed tomography and magnetic resonance imaging; 3) prior studies were based on a psychiatric or neuropsychological perspective as opposed to a neurological assessment and diagnosis
Every doctor's office—a cancer detection center?

Abstract In a survey of 380 physicians—representing 95 per cent of those practicing in a district of a large metropolitan area—it was found that the cancer detection procedures were much better than anticipated. However, the data indicates that the practice of teaching breast self-examination and of doing proctoscopy examinations on asymptomatic patients, needs further emphasis. Results showed that 28 per cent of physicians were not teaching self-examination of the breast to their patients; of those physicians doing proctoscopies more than half did not do them routinely.
Propagation of waves in metallic photonic crystals at low frequencies and some theoretical aspects of left-handed materials

Abstract An analytical theory of low-frequency electromagnetic waves in metallic photonic crystals is presented. The theory is based upon small parameter f⪡1, where f is a volume fraction of the metal in the system. An exact dispersion equation for ω(k) has been obtained and the cutoff frequency ω0=ω(0) as a function of parameters of the photonic crystal has been studied. An analytical expression for the electric permittivity e is calculated. It is shown, that if the crystal is embedded into a medium with negative μ, it has no propagating modes at any frequency. Thus, such a compound system is not a left-handed material.
Generalized Schwinger mass formula

Abstract We generalize Schwinger's original mass formula to the case of an additional isosinglet mixing with the nonet mesons. We then make further generalization to either (i) an arbitrary number of additional isosinglets mixing with nonet mesons, or (ii) an arbitrary number of mesons mixing with an additional isosinglet. In the former case, we present an explicit relation, while in the latter case, we show by numerical example that the new mass formula is only weakly affected by the inclusion of additional mesons, and hence holds with good accuracy for each of the 3×3 mass sub-matrices.
Feedback-stabilized deformable membrane mirrors for focus control

This paper describes a method to extend the range of motion of a deformable, continuous membrane mirror beyond the limit of open-loop electrostatic instability through feedback control. The feedback scheme employs capacitive sensing directly at the mirror actuation electrodes and is based on frequency modulation of a coupled ring oscillator using a differential measurement technique. Analysis of the system shows that the range of stable deflection depends on the relative dynamics of the device and the feedback control circuitry. Experimental results demonstrate stable closed-loop deflection of our silicon nitride membrane test device to 69% of the air gap and confirm the dependence of the maximum stable displacement on overall loop dynamics.
The Relationship between the Length of the Base Period and Population Forecast Errors

Abstract The base period of a population forecast is the time period from which historical data are collected for the purpose of forecasting future population values. The length of the base period is one of the fundamental decisions made in preparing population forecasts, yet very few studies have investigated the effects of this decision on population forecast errors. In this article the relationship between the length of the base period and population forecast errors is analyzed, using three simple forecasting techniques and data from 1900 to 1980 for states in the United States. It is found that increasing the length of the base period up to 10 years improves forecast accuracy, but that further increases generally have little additional effect. The only exception to this finding is long-range forecasts of rapidly growing states, in which a longer base period substantially improves forecast accuracy for two of the forecasting techniques.
A concise synthesis of carolacton.

A synthesis of carolacton, a myxobacterial natural product that has profound effects on Streptococcus mutans biofilms, is reported. The synthesis proceeds via a longest linear sequence of 14 steps from an Evans β-ketoimide and enabled preliminary evaluations of the effects of late-stage intermediates on S. mutans biofilms. These studies suggest that further investigations into carolacton’s structure–function relationships are warranted.
The Discovery of Water Maser Emission from Eight Nearby Galaxies

Using the Green Bank Telescope, we conducted a "snapshot" survey for water maser emission toward the nuclei of 611 galaxies and detected eight new sources. The sample consisted of nearby (v < 5000 km s−1) and luminous (MB < − 19.5) galaxies, some with known nuclear activity but most not previously known to host AGNs. Our detections include both megamasers associated with AGNs and relatively low luminosity masers probably associated with star formation. The detection in UGC 3789 is particularly intriguing because the spectrum shows both systemic and high-velocity lines indicative of emission from an AGN accretion disk seen edge-on. Based on 6 months of monitoring, we detected accelerations among the systemic features ranging from 2 to 8 km s−1 yr−1, the larger values belonging to the most redshifted systemic components. High-velocity maser lines in UGC 3789 show no detectable drift over the same period. Although UGC 3789 was not known to be an AGN prior to this survey, the presence of a disk maser is strong evidence for nuclear activity, and an optical spectrum obtained later has confirmed it. With follow-up observations, it may be possible to measure a geometric distance to UGC 3789.