cssi/SciSciGPT-SciSciNet huggingface dataset:
The Benefits from Agricultural Research and Development, Innovation, and Productivity Growth

This report contains a review of the literature on the role of agricultural research and development in fostering innovation and productivity in agriculture. The review seeks to clarify concepts and terminology used in the area, provide a critical assessment of approaches found in the literature, report main results, and draw inferences. A key finding is that the social rate of return to investments in agricultural R&D has been generally high. Specific findings differ depending on methods and modelling assumptions, particularly assumptions concerning the research lag distribution, the nature of the research-induced technological change, and the nature of the markets for the affected commodities.
Disturbance rejection in nonlinear systems using neural networks

Neural networks with different architectures have been successfully used for the identification and control of a wide class of nonlinear systems. The problem of rejection of input disturbances, when such networks are used in practical problems is considered. A large class of disturbances, which can be modeled as the outputs of unforced linear or nonlinear dynamic systems, is treated. The objective is to determine the identification model and the control law to minimize the effect of the disturbance at the output. In all cases, the method used involves expansion of the state space of the disturbance-free plant in an attempt to eliminate the effect of the disturbance. Several stages of increasing complexity of the problem are discussed in detail. Theoretical justification is provided for the existence of solutions to the problem of complete rejection of the disturbance in special cases. This provides the rationale for using similar techniques in situations where such theoretical analysis is not available. >
A composition theorem for universal one-way hash functions

In this paper we present a new scheme for constructing universal one-way hash functions that hash arbitrarily long messages out of universal one-way hash functions that hash fixed-length messages. The new construction is extremely simple and is also very efficient, yielding shorter keys than previously proposed composition constructions.
Estimación de abundancia y biomasa del cangrejo dorado (Chaceon chilensis), en el archipiélago de Juan Fernández, Chile *

The fishery-biology aspects of the Juan Fernandez golden crab ( Chaceon chilensis), and first estimates of the abundance and biomass of this resource distributed in the marine substrate surrounding Robinson Crusoe and Santa Clara islands are given. Information was obtained from samples taken within an experimental fishing survey for this crustacean, between 175 to 600 m depth, from March to June 1997. The theoretical area of influence methodology was used to estimate the abundance and biomass. Due to the degree of uncertainty of the variables employed, some parameters were sensibilized in order to obtain a range of estimates, along with its most likely value. Results indicate that the fishery of this resource is characterized by its catch mainly composed by males (97,8%), in the different types of traps used as well as in the whole bathymetric range surveyed. Specimens' length were between 84 and 147 mm of cephalothoraxic length. Maximum and minimum observed total weights were 250 and 1410 g respectively. The mean weight of a specimen (male) was 863 g. First most likely estimate of the golden crab available biomass, having sensibilized the area of influence of the trap, was determined to be 995,3 tons, that is a mean density of 2,9 individual/ 1000 m 2 and a maximum sustainable yield (MSY) of 75 tons. In the worst of the estimates scenery a MSY of 19 tons was obtained, and in the most optimistic scenery it reached 168 tons.
Warped black holes in 3D general massive gravity

We study regular spacelike warped black holes in the three dimensional general massive gravity model, which contains both the gravitational Chern-Simons term and the linear combination of curvature squared terms characterizing the new massive gravity besides the Einstein-Hilbert term. The parameters of the metric are found by solving a quartic equation, constrained by an inequality that imposes the absence of closed timelike curves. Explicit expressions for the central charges are suggested by exploiting the fact that these black holes are discrete quotients of spacelike warped AdS 3 and a known formula for the entropy. Previous results obtained separately in topological massive gravity and in new massive gravity are recovered as special cases.
Self-Replication and Self-Assembly for Manufacturing

It has been argued that a central objective of nanotechnology is to make products inexpensively, and that self-replication is an effective approach to very low-cost manufacturing. The research presented here is intended to be a step towards this vision. We describe a computational simulation of nanoscale machines floating in a virtual liquid. The machines can bond together to form strands (chains) that self-replicate and self-assemble into user-specified meshes. There are four types of machines, and the sequence of machine types in a strand determines the shape of the mesh they will build. A strand may be in an unfolded state, in which the bonds are straight, or in a folded state, in which the bond angles depend on the types of machines. By choosing the sequence of machine types in a strand, the user can specify a variety of polygonal shapes. A simulation typically begins with an initial unfolded seed strand in a soup of unbonded machines. The seed strand replicates by bonding with free machines in the soup. The child strands fold into the encoded polygonal shape, and then the polygons drift together and bond to form a mesh. We demonstrate that a variety of polygonal meshes can be manufactured in the simulation, by simply changing the sequence of machine types in the seed.
Definitive radiotherapy for early glottic carcinoma: Prognostic factors and implications for treatment

Abstract Purpose: Treatment and disease-related factors were analyzed for their influence on the outcome of patients treated definitively with irradiation (RT) for early glottic carcinoma. Methods and Materials: One hundre two patients with stage T1 or T2 glottic carcinomas were treated definitively with RT from December 1983 through September 1993. Median follow-up time was 63 months. Factors analyzed for each patients included age, sex, stage, anterior commissure involvement, surgical alternative, histologic differentiation, field size, total dose, fraction size, and total treatment time. Survival analysis methods were employed to assess the effects of these factors on local control and complication rates. Results: The 5-year local control rates by stage were as follows: T1a, 92%, T1b, 80%, T2a, 94%; and T2b, 23%. by univariate analysis, factors found to have a significant impact on local control were stage, surgical alternative, fraction size, anterior commissure involvement, and overall treatment time. By multivariate analysis, stage, field size, and fraction size were the only significant factors that independently influenced local control. Conclusion: The inferior control rate for stage T2b lesions has implications for treatment. Our study supports the conclusion of reports in the literature showing that low fration size negatively influences outcome in patients with early glottic cancer.
Reticular Chemistry: Occurrence and Taxonomy of Nets and Grammar for the Design of Frameworks

The structures of all 1127 three-periodic extended metal−organic frameworks (MOFs) reported in the Cambridge Structure Database have been analyzed, and their underlying topology has been determined. It is remarkable that among the almost infinite number of net topologies that are available for MOFs to adopt, only a handful of nets are actually observed. The discovery of this inversion between expected and observed nets led us to deduce a system of classification “taxonomy” for interpreting and rationalizing known MOF structures, as well as those that will be made in future. The origin of this inversion is attributed to the different modes with which MOF synthesis has been approached. Specifically, three levels of complexity are defined that embody rules “grammar” for the design of MOFs and other extended structures. This system accounts for the present proliferation of MOF structures of high symmetry nets, but more importantly, it provides the basis for designing a building block that “codes” for a specif...
Lessons from the past: Biotic recoveries from mass extinctions

Although mass extinctions probably account for the disappearance of less than 5% of all extinct species, the evolutionary opportunities they have created have had a disproportionate effect on the history of life. Theoretical considerations and simulations have suggested that the empty niches created by a mass extinction should refill rapidly after extinction ameliorates. Under logistic models, this biotic rebound should be exponential, slowing as the environmental carrying capacity is approached. Empirical studies reveal a more complex dynamic, including positive feedback and an exponential growth phase during recoveries. Far from a model of refilling ecospace, mass extinctions appear to cause a collapse of ecospace, which must be rebuilt during recovery. Other generalities include the absence of a clear correlation between the magnitude of extinction and the pace of recovery or the resulting ecological and evolutionary disruption the presence of a survival interval, with few originations, immediately after an extinction and preceding the recovery phase, and the presence of many lineages that persist through an extinction event only to disappear during the subsequent recovery. Several recoveries include numerous missing lineages, groups that are found before the extinction, then latter in the recovery, but are missing during the initial survival–recovery phase. The limited biogeographic studies of recoveries suggest considerable variability between regions.
Cation−Anion Interactions and Polar Structures in the Solid State

Complicated structures where oxygen and fluorine are found together in one framework, where deviations from Pauling's second crystal rule (PSCR) are expected, often result in structures with important physical properties. The [NbOF5]2- anion and therefore all the individual Nb-O and Nb-F bonds are ordered in noncentrosymmetric KNaNbOF5 and centrosymmetric CsNaNbOF5. The Na/K- and Na/Cs-O/F interactions in these phases, in particular the expected deviations from PSCR and the bond valence model, reveal the essential role of the small potassium cations in the acentric packing of the [NbOF5]2- anion. KNaNbOF5 crystallizes in the orthorhombic and polar space group Pna21 (No. 33) with lattice constants a = 11.8653(11) A, b = 5.8826(6) A, c = 8.1258(8) A, and Z = 4, while CsNaNbOF5 crystallizes in the orthorhombic space group Pbcn (No. 60) with lattice constants a = 8.3155(7), b = 13.3176(11), c = 11.1314(9), and Z = 8.
Edit distance and its computation

In this paper, we provide a method for determining the asymptotic value of the maximum edit distance from a given hereditary property. This method permits the edit distance to be computed without using Szemeredi's Regularity Lemma directly. Using this new method, we are able to compute the edit distance from hereditary properties for which it was previously unknown. For some graphs $H$, the edit distance from ${\rm Forb}(H)$ is computed, where ${\rm Forb}(H)$ is the class of graphs which contain no induced copy of graph $H$. Those graphs for which we determine the edit distance asymptotically are $H=K_a+E_b$, an $a$-clique with $b$ isolated vertices, and $H=K_{3,3}$, a complete bipartite graph. We also provide a graph, the first such construction, for which the edit distance cannot be determined just by considering partitions of the vertex set into cliques and cocliques. In the process, we develop weighted generalizations of Turan's theorem, which may be of independent interest.
How Many Phases Meet at the Chiral Critical Point

We explore the phase diagram of Nambu---Jona-Lasinio-type models near the chiral critical point allowing for phases with spatially inhomogeneous chiral condensates. In the chiral limit it turns out that the region in the mean-field phase diagram where those phases are energetically preferred very generically reaches out to the chiral critical point. The preferred inhomogeneous ground state in this vicinity possibly resembles a lattice of domain wall solitons. This raises the question of their relevance for the phase diagram of QCD.
Selection, stability and renormalization

Abstract We illustrate how to extend the concept of structural stability through applying it to the front propagation speed selection problem. This consideration leads us to a renormalization group study of the problem. The study illustrates two very general conclusions: (1) singular perturbations in applied mathematics are best understood as renormalized perturbation methods, and (2) amplitude equations are renormalization group equations.
Reversible Sodium Ion Insertion in Single Crystalline Manganese Oxide Nanowires with Long Cycle Life

Single crystalline Na4Mn9O18 nanowires were synthesized via pyrolysis of polyacrylate salt precursors prepared by in-situ polymerization of the metal salts and acrylate acid, followed by calcinations at an appropriate temperature to achieve good crystalline structure and uniform nanowire morphology with an average diameter of 50 nm. The Na4Mn9O18 nanowires have shown a high, reversible, and near theoretical sodium ion insertion capacity (128 mA h g-1 at 0.1C), excellent long cyclability (77% capacity retention for 1000 cycles at 0.5 C), along with good rate capability. Good capacity and charge-discharge stability are also observed for full cell experiments using a pyrolyzed carbon as the anode, therefore demonstrating the potential of these materials for sodium-ion batteries for large scale energy storage. Furthermore, this research shows that a good crystallinity and small particles are required to enhance the Na-ion diffusion and increase the stability of the electrode materials for long charge-discharge cycles.
High-resolution whole organ imaging using two-photon tissue cytometry

Three-dimensional (3-D) tissue imaging offers substantial benefits to a wide range of biomedical investigations from cardiovascular biology, diabetes, Alzheimer's disease to cancer. Two-photon tissue cytometry is a novel technique based on high-speed multiphoton microscopy coupled with automated histological sectioning, which can quantify tissue morphology and physiology throughout entire organs with subcellular resolution. Furthermore, two-photon tissue cytometry offers all the benefits of fluorescence-based approaches including high specificity and sensitivity and appropriateness for molecular imaging of gene and protein expression. We use two-photon tissue cytometry to image an entire mouse heart at subcellular resolution to quantify the 3-D morphology of cardiac microvasculature and myocyte morphology spanning almost five orders of magnitude in length scales.
Rounding up the wanderers: optimizing coronagraphic searches for extrasolar planets

I derive analytic scalings for coronagraphic imaging searches for extrasolar planets. I compute the efficiency of detecting planets about any given star, and from this compute dimensionless distributionfunctionsforthedetectedplanetsasafunctionofplanet‐stardistanceanddistance to the host stars. I find the following for blind planet surveys: (1) the optimum wavelength is between 4000 and 5000 A for Earth-like planets and 4200 and 5800 A for Jovian planets; (2) between 21 and 32 per cent of the number of planets per decade of radius can be detected with an optimized survey; (3) target stars should be ranked from greatest to least by their luminosity divided by distance to the sixth or eighth power, depending on the dominant source of noise for the survey; (4) surveys targeting all main-sequence stars will detect ! 3 times as many planets as surveys only targeting G-type stars and (5) stellar populations with different metallicities should have exposure times that vary with the cube of the metallicity. I apply these results to the current suite of proposed coronagraphic satellite telescopes, of which TPFC is the most powerful, but a much smaller telescope, TOPS, may have a significant chance of detecting Earth-sized planets due to its small inner working angle and high throughput. The most significant uncertainty in these results is the noise contribution of exo-zodiacal light.
The Natural Cycle: WHY Economic Fluctuations are Inevitable. A Schumpeterian Extension of the Austrian Business Cycle Theory

The conventional version of Austrian business cycle theory focuses on a temporary imbalance between natural and monetary rates of interest. When, because of the role of monetary authorities in defining the monetary rate, the two values are in a situation of imbalance, the resulting expansion stage is followed by a recession. On the other hand, if instead the expansive phase arises without any interference by monetary authorities but through re-adaptation of the productive structure to a modified structure of temporal preferences, a period of sustainable growth begins that will not be followed by a crisis. The purpose of this essay is to demonstrate, on the other hand, that because of profit-expectations and the combined action of Schumpeterian elements (imitations-speculations and the â€˜creation of moneyâ€™ by banks), even a so-called â€˜sustainableâ€™ boom will be affected by a liquidation and settling crisis. What distinguishes the latter situation from the conventional case of imbalance between monetary and natural rates is not the onset or otherwise of a crisis but, rather, its intensity and duration. We will define as natural an economic cycle characterised by a stage of expansion considered to be â€˜sustainableâ€™ in the Austrian theory but followed by an inevitable readjustment crisis.
Quinidine Thiourea-Catalyzed Aldol Reaction of Unactivated Ketones: Highly Enantioselective Synthesis of 3-Alkyl-3-hydroxyindolin-2-ones†

Aldol reaction is one of the most important carbon-carbon bond formation reactions1 and, therefore, many asymmetric variants of this reaction have been developed in the past.1 Since List and Barbas discovered the proline-catalyzed cross aldol reaction of ketones and aldehydes,2 many amine derivatives, mainly proline derivatives, have been developed for the asymmetric cross aldol reactions.3 Mechanistically, these catalysts activate the ketones or enolizable aldehydes through the formation of an enamine intermediate (Scheme 1, upper equation).3 The mechanism is usually a combination of both covalent and noncovalent catalyses since most of these catalysts also contain a hydrogen bonding moiety to direct the approach of the enamine acceptor. In contrast, although enol and enolate (Scheme 1, lower equation) are the active intermediates in the original aldol reactions,4 organocatalyzed enantioselective direct aldol reaction of unactivated ketones via the enolate mechanism is very difficult, because the acidity of the α-proton in these ketones is very low. To our knowledge, there has been no such report.5,6,7 Nevertheless, the enolate mechanism does have certain advantages, especially when the formation of an enamine is difficult. During our study of using activated ketone compounds as the enamine acceptors for the organocatalyzed aldol reactions,8 we envisioned such an organocatalyzed enolate-mediated aldol reaction should be possible if the enolate acceptor is sufficiently activated, because the equilibrium favors the formation of the product with such a substrate. Herein we wish to report the first enantioselective aldol reaction of unactivated ketones involving the enolate mechanism, which may be used for the high enantioselective synthesis of 3-alkyl-3-hydroxyindolin-2-ones.9
J16021+3326: New Multi-Frequency Observations Of a Complex Source

We present multi-frequency Very Long Baseline Array observations of J16021+3326. These observations, along with variability data obtained from the Owens Valley Radio Observatory candidate gamma-ray blazar monitoring program, clearly indicate that this source is a blazar. The peculiar characteristic of this blazar, which daunted previous classification attempts, is that we appear to be observing down a precessing jet, the mean orientation of which is aligned with us almost exactly.
Are recent Arctic ozone losses caused by increasing greenhouse gases

[1] It has been suggested that the Arctic ozone losses observed in recent years might be a manifestation of climate change due to increasing greenhouse gases. We here offer evidence to the contrary, by focusing on the volume of polar stratospheric clouds (VPSC), a convenient proxy for polar ozone loss whose simplicity allows for easily reproducible results. First, we analyze the time series of VPSC in three reanalysis data sets and find no statistically significant trends in VPSC–nor changes in their probability density functions–over the period 1979–2011. Second, we analyze VPSC in a stratosphere-resolving chemistry-climate model forced uniquely with increasing greenhouse gases following the A1B scenario: here too, we find no significant changes in VPSC over the entire 21st century. Taken together, these results strongly suggest that the sporadic high ozone losses in recent years have not been caused by increasing greenhouse gases.
The Impact of Health Care and Immigration Reform on Latino Support for President Obama and Congress

At the start of their term, the Obama administration pledged to reform two failing policy systems in the United States: immigration and health care. The Latino populations’ attitudes toward these t...
Reliability-Based Control Design for Uncertain Systems

This paper presents a robust control design methodology for systems with probabilistic parametric uncertainty. Control design is carried out by solving a reliability-based multi-objective optimization problem where the probability of violating design requirements is minimized. Simultaneously, failure domains are optimally enlarged to enable global improvements in the closed-loop performance. To enable an ecient numerical implementation, a hybrid approach for estimating reliability metrics is developed. This approach, which integrates deterministic sampling and asymptotic approximations, greatly reduces the numerical burden associated with complex probabilistic computations without compromising the accuracy of the results. Examples using output-feedback and full-state feedback with state estimation are used to demonstrate the ideas proposed.
Opto-mechanical modal spectroscopy: Opto-excited vibrations of a micron-scale on-chip resonator

Radiation pressure is used to excite vibrational modes of an optical micro-cavity at GHz rates. Many spectral lines associated with high-order vibrational modes are measured. Perturbation of the cavity geometry is observed to induce splitting of the spectral lines. copy 2007 Optical Society of America OCIS codes: (230.1040) Acousto-optical devices: (300.6330) Spectroscopy, inelastic scattering including Raman.
Acoustic Surface-Wave Recirculating Memory

An acoustic surface-wave memory is described, operating at a bit rate of 220 MHz and storage capcity of 1280 bit-per recirculation loop. The transducers are coded using orthogonal pairs of Golay complementary sequences to obtain pulse-in pulse-out behavior. The shape of the delayed pulse is analyzed and compared with the pulse shape that is obtained using a simple single finger pair transducer. The recirculation electronics uses standard MECL-III logic for both the amplifier and the write, read, inhibit, and reclocking functions. The cost of the recirculating memory and the feasibility of constructing larger capacity stores are also discussed.
Dolphin sympatric ecology

Abstract Interspecific associations between two or more species of the family Delphinidae have been reported by many scientists, but the sympatric ecology of such dolphin associations has not been studied in great detail. A few field investigations have been conducted on this subject in different parts of the world on species such as bottlenose dolphins (Tursiops spp.), short-beaked common dolphins (Delphinus delphis), and killer whales (Orcinus orca). Sympatric dolphins seem to use different strategies to co-exist when resources appear to be limited, including dietary divergence (different prey preference, slightly diverse diet, different feeding time) and/or different habitat use (shallow versus deep waters, flat areas versus submarine canyons and escarpments, different travel routes). This paper presents a review of some well-studied dolphin species found in sympatry and discusses the nature of habitat and resource partitioning as well as studies on aggressive behaviour displayed by species living in t...
Velocity-density systematics and its implications for the iron content of the mantle

A unified relation among the hydrodynamic velocity Vϕ, the density ρ, the mean atomic weight m, and Poisson's ratio σ is proposed for oxides, silicates, and germanates as Vϕ = Vϕ+ - 0.058(m - m0) - 2.62(ρ − ρ0), where Vϕ+ = −1.84 + 7.51 σ + 1.98ρ and ρ0 is the density of the crystallographically isostructural material of m = m0 = 20.2. The proposed relation can be considered as a linear form of the power law relation proposed by Shankland and Chung (1974). However, the incorporation of σ into the present relation would give a better correlation among the various parameters. It would also accommodate the velocity data of α quartz as well as those of materials undergoing various phase transformations. The value of the mean atomic weight calculated from this relation for various earth models implies that iron enrichment in the lower mantle with respect to the upper mantle is not necessary.
GRB 021004: Reverse Shock Emission

We show that the rebrightening in the GRB 021004 optical afterglow light curve can be explained within the framework of the standard fireball model. The optical light curve of the forward shock emission is expected to rise initially and to decay after the typical synchrotron frequency crosses the optical band. We show that such a rising phase emission was caught for GRB 021004, together with a reverse shock emission. With the standard values of parameters obtained in other afterglow observations, we can construct example cases in which theoretical estimates reasonably fit the broadband observations. Therefore, the early rebrightening might be a common feature in optical afterglows.
On the Nature of the Transition Disk Around LkCa 15

We present Combined Array for Research in Millimeter-wave Astronomy 1.3 mm continuum observations of the T Tauri star LkCa 15, which resolve the circumstellar dust continuum emission on angular scales between 0"2 and 3", corresponding to 28-420 AU at the distance of the star. The observations resolve the inner gap in the dust emission and reveal an asymmetric dust distribution in the outer disk. By comparing the observations with theoretical disk models, we calculate that 90% of the dust emission arises from an azimuthally symmetric ring that contains about 5 × 10^(–4) M_☉ of dust. A low surface-brightness tail that extends to the northwest out to a radius of about 300 AU contains the remaining 10% of the observed continuum emission. The ring is modeled with a rather flat surface density profile between 40 and 120 AU, while the inner cavity is consistent with either a sharp drop of the 1.3 mm dust optical depth at about 42 AU or a smooth inward decrease between 3 and 85 AU. We show that early science Atacama Large Millimeter Array observations will be able to disentangle these two scenarios. Within 40 AU, the observations constrain the amount of dust between 10^(–6) and 7 Earth masses, where the minimum and maximum limits are set by the near-infrared spectral energy distribution modeling and by the millimeter-wave observations of the dust emission, respectively. In addition, we confirm the discrepancy in the outer disk radius inferred from the dust and gas, which corresponds to 150 AU and 900 AU, respectively. We cannot reconcile this difference by adopting an exponentially tapered surface density profile as suggested for other systems, but we instead suggest that the gas surface density in the outer disk decreases less steeply than that predicted by model fits to the dust continuum emission. The lack of continuum emission at radii larger than 120 AU suggests a drop of at least a factor of five in the dust-to-gas ratio or in the dust opacity. We show that a sharp dust opacity drop of this magnitude is consistent with a radial variation of the grain size distribution as predicted by existing grain growth models.
Nonlinear fixed-order dynamic compensation for passive systems

A method for designing nonlinear fixed-order (i.e. full- and reduced-order) dynamic passive controllers for passive systems is developed using nonlinear dissipation theory. Specifically, by extending linear passive controller synthesis frameworks a family of globally asymptotically stabilizing nonlinear passive controllers is developed that can serve to enhance system performance and energy dissipation. The proposed approach is applied to the rotational/translational proof-mass actuator (RTAC) nonlinear benchmark problem to develop fixed-order dynamic output feedback nonlinear controllers. © 1998 John Wiley & Sons, Ltd.
Valuation of Bankrupt Firms

This study compares the market value of firms that reorganize in bankruptcy with estimates of value based on management’s published cash flow projections. We estimate firm values using models that have been shown in other contexts to generate relatively precise estimates of value. We find that these methods generally yield unbiased estimates of value, but the dispersion of valuation errors is very widethe sample ratio of estimated value to market value varies from less than 20% to greater than 250%. Cross-sectional analysis indicates that the variation in these errors is related to empirical proxies for claimholders’ incentives to overstate or understate the firm’s value.
Infrared Properties of z=7 Galaxies from Cosmological Simulations

Three-dimensional panchromatic dust radiative transfer calculations are performed on a set of 198 galaxies of stellar masses in the range of 5 ? 108 to 3 ? 1010 M ? from a cosmological hydrodynamic simulation (resolved at 29?h ?1?pc) at z ~ 7. In a companion paper, the stellar mass and UV luminosity functions and the UV-optical and FUV-NUV colors are shown to be in good agreement with observations if a Small Magellanic Cloud type dust extinction curve is adopted. Here, we make useful predictions, self-consistently, of the infrared properties of these z ~ 7 simulated galaxies that can be confronted with upcoming ALMA data. Our findings are as follows. (1) The effective radius in the rest-frame MIPS70 ?m band is in the range of 80-400?pc proper for z = 7 galaxies with L FIR = 1011.3-1012 L ?. (2) The median of the peak wavelength of the far-infrared (FIR) spectral energy distribution is in the range of 45-60 ?m, depending on the dust-to-metal ratio. (3) For star formation rate in the range of 3-100 M ??yr?1, the median FIR to bolometric luminosity ratio is 60%-90%. (4) The FIR luminosity function displays a power law in the high end with a slope of ?3.1 ? 0.4 instead of the usual exponential decline.
Magnetic nanowire-enhanced optomagnetic tweezers

We present an optomagnetic tweezers technique that utilizes the highly localized magnetic field gradients generated near the tip of a magnetic nanowire to provide strong trapping forces on magnetic nanoparticles with high spatial resolution. Integral to the approach is a method to trap, translate, and rotate a single magnetic nanowire in three dimensions; this nanowire is in turn capable of exerting forces on magnetic nanoparticles. Our simulation predicts that forces in the range of 100 pN can be generated on 200 nm magnetic particles within a distance of 0.3 µm from a 200 nm diameter nickel nanowire, magnetized to saturation. Such forces are relevant in many biological processes, suggesting this approach may be of value in biophysical studies.
Cost-Distance: Two Metric Network Design

We present the Cost-Distance problem: finding a Steiner tree which optimizes the sum of edge costs along one metric and the sum of source-sink distances along an unrelated second metric. We give the first known $O(\log k)$ randomized approximation scheme for Cost-Distance, where $k$ is the number of sources. We reduce several common network design problems to Cost-Distance, obtaining (in some cases) the first known logarithmic approximation for them. These problems include single-sink buy-at-bulk with variable pipe types between different sets of nodes, facility location with buy-at-bulk-type costs on edges (integrated logistics), constructing single-source multicast trees with good cost and delay properties, priority Steiner trees, and multilevel facility location. Our algorithm is also easier to implement and significantly faster than previously known algorithms for buy-at-bulk design problems.
A computational and experimental study of slit resonators

Abstract Computational and experimental studies are carried out to offer validation of the results obtained from direct numerical simulation (DNS) of the flow and acoustic fields of slit resonators. The test cases include slits with 90° corners and slits with 45° beveled edges housed inside an acoustic impedance tube. Slit widths of 0.05, 0.10 and 0.20 in are used. Six frequencies from 0.5 to 3.0 kHz are chosen. Good agreement is found between computed and measured reflection factors. To provide a more critical test, comparisons are also made at frequencies near a natural resonance of the resonator. Again, good agreement is obtained. In addition, incident sound waves having a white noise spectrum and a prescribed pseudo-random noise spectrum are used in a subsequent series of tests. The computed broadband results are again found to agree well with experimental data. It is believed the present results provide strong support that DNS can eventually be a useful and accurate prediction tool for liner aeroacoustics. The usage of DNS as a design tool is discussed and illustrated by a simple example.
Anyon spin and the exotic central extension of the planar Galilei group

Abstract We show that the second central extension of the Galilei group in (2+1) dimensions corresponds to spin, which can be any real number.
Runge-Kutta-Chebyshev projection method

In this paper a fully explicit, stabilized projection method called the Runge-Kutta-Chebyshev (RKC) projection method is presented for the solution of incompressible Navier-Stokes systems. This method preserves the extended stability property of the RKC method for solving ODEs, and it requires only one projection per step. An additional projection on the time derivative of the velocity is performed whenever a second-order approximation for the pressure is desired. We demonstrate both by numerical experiments and by order analysis that the method is second order accurate in time for both the velocity and the pressure. Being explicit, the RKC projection method is easy to implement and to parallelize. Hence it is an attractive candidate for the solution of large-scale, moderately stiff, diffusion-like problems.
Electrochemically enabled polyelectrolyte multilayer devices: from fuel cells to sensors

With an ever-increasing need for thin, flexible and functional materials in electrochemical systems, the layer-by-layer (LbL) technique provides a simple and affordable route in creating new, active electrodes and electrolytes. The LbL technique, which is based upon the alternate adsorption of oppositely charged species from aqueous solution, possesses unprecedented control of materials selection (e.g. polyelectrolytes, clays, nanoparticles, proteins), materials properties (e.g. conductivity, glass-transition temperature) and architecture (e.g. blends, stratified-layers, pores). These advantages make LbL assemblies excellent candidates for use in proton-exchange membrane and direct methanol fuel-cells, batteries, electrochromic devices, solar cells, and sensors. This review addresses the design of LbL films for electrochemical systems and recent progress.
Crossings, colorings, and cliques

Albertson conjectured that if graph G has chromatic number r, then the crossing number of G is at least that of the complete graph Kr. This conjecture in the case r = 5 is equivalent to the four color theorem. It was verified for r = 6 by Oporowski and Zhao. In this paper, we prove the conjecture for 7 ≤ r ≤ 12 using results of Dirac; Gallai; and Kostochka and Stiebitz that give lower bounds on the number of edges in critical graphs, together with lower bounds by Pach et al. on the crossing number of graphs in terms of the number of edges and vertices.
Turbo-Coded APSK for aeronautical telemetry

The performance of turbo-coded Amplitude-Phase Shift Keying (APSK) in an aeronautical telemetry system with a non-linear power amplifier is investigated. The AM/AM curves for four L-band power amplifiers are modeled and used to simulate the performance the turbo-coded APSK system over a non-linear channel, Spectral efficiency and bit error rate performance as a function of back-off are quantified and compared with a system based on the existing aeronautical telemetry standard using uncoded SOQPSK. The results show that the -50 dBc bandwidth can be matched with 2.5 to 4.1 dB of back-off, the -60dBc bandwidth can be matched with 4.3 to 6.6 dB of back-off, and the 99%. bandwidth can be matched with 0.8 to 1.6 dB of back-off. The bit error rate results show that each power amplifier has an optimal back-off and that this back-off is 3 dB for the four amplifiers used in this study. When put together, this system is capable of outperforming an uncoded system based on SOQPSK by matching (or exceeding) the detection efficiency while simultaneously achieving a spectral efficiency in excess of three times that of SOQPSK.
Title IX and the evolution of high school sports

The passage of Title IX, the 1972 Education Amendments to the Civil Rights Act, expanded high school athletic opportunities to include girls, revolutionizing mass sports participation in the United States. This paper analyzes high school athletic participation in the United States and how sports offerings for boys and girls changed subsequent to the passage of this legislation. Girls’ sports participation rose dramatically both following the enactment of Title IX and subsequent to enhancements to its enforcement. Approximately half of all girls currently participate in sports during high school; however, there remains a substantial gap between girls and boys participation in many states. States’ average education level and social attitudes regarding Title IX and women’s rights are correlated with this remaining gender gap. Examining individual high school students, sports participation is seen more frequently among those with a privileged background: white students with married, wealthy, educated parents are more likely to play sports. This finding points to an overlooked fact—while Title IX benefited girls by increasing the opportunity to play sports, these benefits were disproportionately reaped by those at the top of the income distribution. (JEL J16, J18, J24, I2)
Quantifying Limits to Detection of Early Warning for Critical Transitions

Catastrophic regime shifts in complex natural systems may be averted through advanced detection. Recent work has provided a proof-of-principle that many systems approaching a catastrophic transition may be identified through the lens of early warning indicators such as rising variance or increased return times. Despite widespread appreciation of the difficulties and uncertainty involved in such forecasts, proposed methods hardly ever characterize their expected error rates. Without the benefits of replicates, controls or hindsight, applications of these approaches must quantify how reliable different indicators are in avoiding false alarms, and how sensitive they are to missing subtle warning signs. We propose a model-based approach to quantify this trade-off between reliability and sensitivity and allow comparisons between different indicators. We show these error rates can be quite severe for common indicators even under favourable assumptions, and also illustrate how a model-based indicator can improve this performance. We demonstrate how the performance of an early warning indicator varies in different datasets, and suggest that uncertainty quantification become a more central part of early warning predictions.
An analysis and design method for linear systems under nested saturation

This paper considers a linear system under nested saturation. Nested saturation arises, for example, when the actuator is subject to magnitude and rate saturation simultaneously. A condition is derived in terms of a set of auxiliary feedback gains for determining if a given ellipsoid is contractively invariant. Moreover, this condition is shown to be equivalent to linear matrix inequalities (LMIs) in the actual and auxiliary feedback gains. As a result, the estimation of the domain of attraction for a given set of feedback gains can be formulated as an optimization problem with LMI constraints. By viewing the feedback gains as extra free parameters, the optimization problem can be used for controller design.
Monetary policy, structural break, and the monetary transmission mechanism in Thailand

The paper studies monetary policy and the monetary transmission mechanism in Thailand in light of the Asian crisis in 1997. Existing studies that adopt structural vector auto-regression (VAR) approaches do not give a clear and agreed-upon view how monetary shocks are transmitted to the Thai economy that is subject to structural breaks. This study explicitly models a pre-crisis and post-crisis cointegrated VAR model. This analysis supports arguments that the trinity of open capital markets, pegged exchange rate regime, and monetary policy autonomy is inconsistent in the pre-crisis period. In contrast, the model points to an effective monetary policy in the post-crisis period. Further, the author analyzes the common driving trends of the model.
Polar nephelometer for atmospheric particulate studies

A unique polar nephelometer was designed and constructed for the measurement of atmospheric particulate characteristics. The nephelometer produces visible light from a self-contained laser to irradiate an air sample drawn into the instrument. The light scattered from the particulates and molecules in the sample is detected as a function of scattering angle for each of four different incident light polarizations. These measurements are used to determine the particulate scattering matrix which is a function of the size, shape, and index of refraction of the particles. The region of sensitivity for the measurements corresponds to the size range of particles that strongly affects visible radiative transfer in the atmosphere, which is the primary application for the derived information.
FERTILITY AND THE PERSONAL EXEMPTION: COMMENT

One of the most commonly cited studies on the effect of child subsidies on fertility, Whittington, Alm, and Peters (1990), claimed a large positive effect of child tax benefits on fertility using time series methods. We revisit this question in light of recent increases in child tax benefits by replicating this earlier study and extending the analysis. We do not find strong evidence to justify the model specification from the original paper. Moreover, even if the original specification is appropriate, we show that the results are not robust to more general measures of child tax benefits. (JEL H24, J13)
Voice rest after microlaryngoscopy: current opinion and practice.

Objective: Although voice rest is often recommended after excision of benign mucosal vocal fold lesions, no standard of care exists regarding the use, duration, or extent of vocal restrictions. This prospective study is intended to explore current opinions and practices of otolaryngologists regarding the use of complete and relative voice rest. Study Design and Methods: A 16-item survey was mailed to all active U.S. members of the American Academy of Otolaryngology-Head and Neck Surgery (n 7,321) regarding use of complete and relative voice rest after surgical excision of vocal fold nodules, polyps, and cysts. Treatment preference questions used a Likert 5-point scale with end anchors of 1 equaling “never” and 5 equaling “always”. Results: The response rate was 16.5% (1,208 respondents). Differences by lesion type were not statistically significant, suggesting that surgeons consider the mucosal disruption resulting from the surgery to be similar across lesions. Approximately 51.4% (620) favored complete voice rest. Approximately 62.3% (753) favored relative voice rest. Approximately 18% (213) of the respondents who “always” recommend complete rest also “always” recommend relative rest. The most common duration for both types of rest is 7 days. Conclusions: There is a clear preference for the use of voice rest, but the specific type (complete or relative) is controversial, and a notable percentage of respondents (15%) do not favor any type of voice rest. It is likely that the lack of uniformity of opinions and practices reflects the absence of empirical data. Prospective clinical trials are needed to guide clinical standards of care. Key words: Voice rest, phonosurgery, microlaryngoscopy, nodules, polyp, cyst. Laryngoscope, 113:2182–2186, 2003
ALTITUDE LIMITS FOR ROTATING VECTOR MODEL FITTING OF PULSAR POLARIZATION

Traditional pulsar polarization sweep analysis starts from the point dipole rotating vector model (RVM) approximation. If augmented by a measurement of the sweep phase shift, one obtains an estimate of the emission altitude (Blaskiewicz et al.). However, a more realistic treatment of field line sweepback and finite altitude effects shows that this estimate breaks down at modest altitude ~0.1 R LC. Such radio emission altitudes turn out to be relevant to the young energetic and millisecond pulsars that dominate the γ-ray population. We quantify the breakdown height as a function of viewing geometry and provide simple fitting formulae that allow observers to correct RVM-based height estimates, preserving reasonable accuracy to R ~ 0.3 R LC. We discuss briefly other observables that can check and improve height estimates.
Compression of the layered depth image

A layered depth image (LDI) is a new popular representation and rendering method for objects with complex geometries. Similar to a two-dimensional (2-D) image, the LDI consists of an array of pixels. However, unlike the 2-D image, an LDI pixel has depth information, and there are multiple layers at a pixel location. We develop a novel LDI compression algorithm that handles the multiple layers and the depth coding. The algorithm records the number of LDI layers at each pixel location, and compresses LDI color and depth components separately. For LDI layer with sparse pixels, the data is aggregated and then encoded. An empirical rate-distortion model is used to optimally allocate bits among different components. Compared with the benchmark compression tools such as JPEG-2000 and MPEG-4, our scheme improves the compression performance significantly.
Free Extreme Values

Free probability analogues of the basics of extreme value theory are obtained, based on Ando's spectral order. This includes clas- sification of freely max-stable laws and their domains of attraction, using "free extremal convolutions" on the distributions. These laws coincide with the limit laws in the classical peaks-over-threshold approach. A free extremal projection-valued process over a measure-space is constructed, which is related to the free Poisson point process.