cssi/SciSciGPT-SciSciNet huggingface dataset:
Make, Buy, or Ally? Choice of and Payoff from Announcements of Alternate Strategies for Innovations

Firms constantly grapple with the question of whether to make, buy, or ally for innovations. The literature has not, to our knowledge, analyzed the choice of and payoff from these alternate routes to innovation for the same firm. To address this issue, we collect, code, and analyze the choice of and payoff from 3,522 announcements of make, buy, and ally for 192 firms across 108 industries over five years. We find that announcements to make or ally generate positive and higher payoffs than announcements to buy, which generate negative payoffs. Nevertheless, firms continue to buy for two reasons. First, firms seem to have no memory of the payoff from buy, even though they have a memory of the payoff from make. Second, firms tend to buy when they lack commercializations, even though this strategy does not always seem to pay off. These results suggest that firms see buy as a signal to investors that they have a solution for what may be a deep strategic problem. Nevertheless, the negative returns to a buy can be mitigated if the acquirer is experienced, and the target is related and offers high customer benefit. We offer explanations for and implications of the results.
Measuring Molecular, Neutral Atomic, and Warm Ionized Galactic Gas Through X-Ray Absorption

We study the column densities of neutral atomic, molecular, and warm ionized Galactic gas through their continuous absorption of extragalactic X-ray spectra at |b|>25°. For NH, 21 cm 5×1020 cm-2, which occurs at our lower latitudes, the X-ray absorption column NH, x is nearly double NH, 21 cm. This excess column cannot be due to the warm ionized component even if He were entirely He I, so it must be due to a molecular component. This result implies that for lines of sight out of the plane with |b|~30°, molecular gas is common, with a column density comparable to NH, 21 cm. This work bears upon the far-infrared background, since a warm ionized component, anticorrelated with NH, 21 cm, might produce such a background. Not only is such an anticorrelation absent, but if the dust is destroyed in the warm ionized gas the far-infrared background may be slightly larger than that deduced by Puget and coworkers.
Analysis of finite temperature phase transition using level spacing

Abstract Let B be the largest spacing between adjacent eigenvalues of the Polyakov loop. We propose to employ the distribution of B as an order parameter for the finite temperature phase transition in SU(N) lattice gauge theories. Using smeared links to reduce ultraviolet fluctuations, we carry out a test for the gauge group SU (3).
Assessing the welfare impacts of public spending

An important objective of public spending is to raise household living standards, particularly for the poor. But how can final impacts on this objective best be assessed? Evaluating a policy's impact requires assessing how different things would have been in its absence. But the counterfactual of no intervention is tricky to quantify. The author surveys the methods most often used to assess the welfare effects of public spending. Limitations of current practices are studied and implications for future best practices are drawn. The methods used to assess welfare impacts broadly fall into two groups: benefit incidence studies and behavioral approaches. Benefit incidence studies ignore behavioral responses and second-round effects, using the provision cost as a proxy for benefits received. Behavioral approaches present quite different drawbacks, in attempting to represent individual benefits correctly. A number of recent studies usefully combine both approaches. It is still uncertain whether behaviorally consistent methods actually point to fundamentally different policy recommendations. What can be concluded is that we need to diversify and compare results from our evaluation methods and broaden our definition of well-being, to see how various facets of living standard are affected by public spending.
Fear and loathing in Mississippi: the attack on cAMP sister spirit.

SUMMARY In 1993, the small rural community of Ovett, Miss., and a group of self-described radical lesbian feminists clashed over the establishment by the women of a feminist educational retreat known as Camp Sister Spirit. This dispute took the form of physical and psychological harassment of the women, wide-open public debate in the community, in the press, and on television, federal mediation efforts, and two lawsuits. This article analyzes this dispute using Mary Daly's seven patterns of the sado-ritual syndrome (Daly, 1978). The analysis examines the ideological and moral standpoints of the participants, the issues of “blaming the victim” and scapegoating, the development of the conflict from a dispute between neighbors to the involvement of international media, national activists and the Clinton Administration, the transformation of the conflict from a political to legal dispute, the representations of the groups within the community and the media, the effect of public opinion on the dispute, and the...
A heat pipe mechanism for volcanism and tectonics on Venus

A heat-pipe mechanism is proposed for the transport of heat through the lithosphere of Venus. This mechanism allows the crust and lithosphere on Venus to be greater than 150 km. thick. A thick basaltic crust on Venus is expected to transform eclogite at a depth of 60 to 80 km; the dense eclogite would contribute to lithospheric delamination that returns the crust to the interior of the planet completing the heat-pipe cycle. Topography and the associated gravity anomalies can be explained by Airy compensation of the thick crust. The principal observation that is contrary to this hypothesis is the mean age of the surface that is inferred from crater statistics; the minimum mean age is about 130 Myr and this implies an upper limit of 2 cubic kilometers per year for the surface volcanic flux. If the heat-pipe mechanism was applicable on the Earth in the Archean it would provide the thick lithosphere implied by isotopic data from diamonds.
Mixing of primordial gas in Lyman break galaxies

Motivated by a recent interpretation of z ~ 3 objects, we examine processes that control the fraction of primordial (Z = 0) gas, and so primordial stars, in high star formation rate Lyman break galaxies (LBGs). A primordial fraction different from 1 or 0 requires microscopic diffusion catalyzed by a velocity field with a timescale comparable to the duration of star formation. The only process we found that satisfies this requirement for LBGs without fine-tuning is turbulence-enhanced mixing induced by exponential stretching and compressing of metal-rich ejecta. The time dependence of the primordial fraction for this model is calculated. We show that conclusions for all the models discussed here are virtually independent of the initial mass function (IMF), including extremely top-heavy IMFs.
van der Waals forces in the noble metals

The van der Waals (or polarization) force between ions in the noble metals is calculated within a simplified model in which the ions are regarded as nonoverlapping and immersed in a uniform electron gas. The conduction-electron screening of the ion-ion interactions is straightforwardly taken into account. Using effective ionic polarizabilities derived from the measured optical constants, we find that the contribution of the polarization forces to the cohesive energy per atom is 0.21, 0.42, and 0.63 eV for Cu, Ag, and Au, respectively. By comparison, the total cohesive energies in these metals are 3.50, 2.96, and 3.78 eV, respectively.
Coping with City Growth during the British Industrial Revolution

Coping with City Growth assesses Britain's handling of city growth during the First Industrial Revolution by combining the tools used by Third World analysts with the archival attention and eclectic style of the economic historian. What emerges is an exciting and provocative accounts that have long occupied problem development economists: urban unemployment, underemployment, and the alleged failure of city labour markets to absorb the flood of rural emigrants; the persistent influx of newcomers, which makes it difficult for municipal planners to improve the quality of social overhead; the crowding of migrants into densely packed urban slums with few, if any, social services; and rising density and city size which augment pollution while lowering the quality of the urban environment.
The Limited Effects of Federal Environmental Justice Policy on State Enforcement

The federal government adopted several measures during the mid-1990s to address concerns about race-based and class-based disparities in environmental protection. This article examines whether these measures affected the pattern of state enforcement of three federal pollution control laws. Using differences-in-differences models to estimate the effects of the federal policy adoption, I find evidence of increases in state enforcement of the Clean Air Act in large African-American communities, but declines in enforcement in communities with large poor and Hispanic populations. Similarly, there is evidence that state enforcement of the Clean Water Act decreased in poor and African-American communities, but there were no real changes in enforcement of facilities regulated under the Resource Conservation and Recovery Act. Collectively, the analysis suggests that the federal policy had minimal positive effects on state regulatory enforcement.
p-nitrobenzyloxymethyl: A new fluoride-removable protecting group for ribonucleoside 2′-hydroxyls

Abstract A novel protecting group for the 2′-hydroxyl of ribonucleosides, p-nitrobenzyloxymethyl, is used in the rapid solid phase synthesis of the oligonucleotide U(U)11U; it can be readily removed from the oligomer product by treatment with tetrabutylammonium fluoride.
Is systemic right ventricular function by cardiac MRI related to the degree of tricuspid regurgitation in congenitally corrected transposition of the great arteries

Abstract Background and Methods Systemic right ventricular dysfunction and tricuspid regurgitation (TR) are frequently encountered in patients with congenitally corrected transposition of the great arteries (CCTGA). Studies using echocardiography have suggested a relationship between the degree of TR and systemic right ventricular dysfunction; however, assessment of systemic right ventricular function by echocardiography is limited. Cardiac MRI (CMR) is the gold standard for volumetric assessment of the systemic right ventricle. We performed a retrospective cohort study at our center evaluating all adult patients with CCTGA who underwent a CMR between 1/1999 and 1/2013 to determine the relationship between the degree of TR and systemic right ventricular function. Results Of the 33 patients identified, 12 had ≤mild TR (37%), 13 had moderate TR (40%), and 8 had severe TR (24%). Mean age at CMR was 38years (23–64). Mean right ventricular ejection fraction (45% vs. 41% vs. 42%, p =0.68) and mean indexed right ventricular end diastolic volume (122ml/m 2 vs. 136ml/m 2 vs. 138ml/m 2 p =0.36) were not significantly different for patients with ≤mild TR, moderate TR or severe TR. The degree of TR was not associated with additional congenital lesions, prior procedures, presence of an intraventricular conduction delay, or decreased left ventricular function. Conclusion No association between the degree of TR and right ventricular volume or ejection fraction by CMR was identified. Failure to show worsening function or increased volume with greater degrees of TR suggests that the degree of regurgitation alone may not fully explain the heterogeneity in right ventricular size and function.
On divergence form SPDEs with VMO coefficients in a half space

Abstract We extend several known results on solvability in the Sobolev spaces W p 1 , p ∈ [ 2 , ∞ ) , of SPDEs in divergence form in R + d to equations having coefficients which are discontinuous in the space variable.
Microporous oxides by the sol-gel process: synthesis and applications

Abstract The synthesis of silica, alumina and zirconia by the sol-gel process is described. In each case, the reagent is the appropriate metal alkoxide. The preparations for supported oxides, where the gel is attached to a rigid support, and unsupported oxides are compared because of the importance of both forms as membrane materials.
Synthesis of N2-(2-aminofluoren-3-yl) adducts of 2′-deoxyguanosine

A direct route is described for the synthesis of N2-(2-aminofluoren-3-yl)-2′-deoxyguanosine 3a and N2-(2-acetylaminofluoren-3-yl)-2′-deoxyguanosine 3b.
Investigation of the transitions in UPd3

Abstract Specific heat measurements below 20 K on UPd 3 in different magnetic fields up to 13 T are presented. With no field the sample shows a sharp transition at 6.37 K accompanied by two smaller maxima at 4.35 and 7.45 K. In the field these maxima shift upwards in temperature. In addition, the strain sensitivity of the anomalies has been investigated through specific heat measurements on a pressed pellet of finely ground powder. The main peak decreases in size upon grinding and its transition temperature goes down to 5.6 K. The results are interpreted to distinguish between the extant competing explanations of the main anomaly, as well as to shed light on the two smaller transitions.
Differential rotation and meridional circulation in global models of solar convection

In the outer envelope of the Sun and in other stars, differential rotation and meridional circulation are maintained via the redistribution of momentum and energy by convective motions. In order to properly capture such processes in a numerical model, the correct spherical geometry is essential. In this paper I review recent insights into the maintenance of mean flows in the solar interior obtained from high-resolution simulations of solar convection in rotating spherical shells. The Coriolis force induces a Reynolds stress which transports angular momentum equatorward and also yields latitudinal variations in the convective heat flux. Meridional circulations induced by baroclinicity and rotational shear further redistribute angular momentum and alter the mean stratification. This gives rise to a complex nonlinear interplay between turbulent convection, differential rotation, meridional circulation, and the mean specific entropy profile. I will describe how this drama plays out in our simulations as well as in solar and stellar convection zones. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Effects of one- and three-day binge alcohol exposure in neonatal C57BL/6 mice on spatial learning and memory in adolescence and adulthood

Binge-like alcohol exposure during the early postnatal period in rats and mice causes deficits in spatial learning and memory that persist into adulthood. Wozniak et al. (2004) reported that heavy binge alcohol exposure on postnatal day 7 (PD 7) in C57BL/6 (B6) mice produced profound spatial learning deficits in the Morris water maze when tested in adolescence (P30–39); when tested in adulthood, however, the deficits were greatly attenuated. Using a similar PD 7 binge alcohol exposure paradigm in B6 mice, we tested whether a single-day (PD 7 only) alcohol treatment produced place learning deficits in both adolescence and in adulthood, and further tested whether a more extended (3-day, PD 7–9) alcohol exposure would induce more severe and enduring deficits. B6 mice were given either 2 subcutaneous injections of alcohol (2.5 g/kg each) 2 h apart on PD 7 or on PD 7–9, and compared with controls that received saline vehicle injections and controls that received no injections. The alcohol injections on PD 7 produced average peak blood alcohol concentrations of 472 mg/dL and evoked typical patterns of activated caspase-3-positive neurons in the cortex, hippocampal formation, and striatum 6 h after the last injection. Mice were given standard place training or random location training in the Morris water maze either as adolescents (PD 30–39) or adults (PD 70–79). The adolescents acquired the place learning more slowly than adults, and the alcohol treatments produced only modest place acquisition deficits. In contrast, both the PD7 and the PD 7–9 alcohol treatments resulted in large and significant spatial learning impairments in adults. In contrast to the previous findings of Wozniak et al. (2004), these results indicate that binge alcohol exposure in the 3rd trimester equivalent produces significant and enduring deficits in spatial learning in B6 mice.
Shintani’s zeta function is not a finite sum of Euler products

We prove that the Shintani zeta function associated to the space of binary cubic forms cannot be written as a finite sum of Euler products. Our proof also extends to several closely related Dirichlet series. This answers a question of Wright in the negative.
Morphology and hazards related to nearshore ice in coastal areas

Abstract The objective of this study was to develop a general morphology of nearshore ice along the Beaufort, Chukchi and Bering coasts of Alaska, and identify those features which may represent hazards imposed by ice conditions on outer continental shelf oil and gas development. Landsat imagery has been utilized to map major winter and spring Beaufort, Chukchi, and Bering Sea nearshore ice conditions for 1973–1977 related to regional ice morphology. Following this, significant features from individual Landsat image maps have been combined to yield regional maps of major ice ridge systems for each year of study and maps of flaw lead systems for representative seasons during each year of study. These regional maps have, in turn, been used to prepare seasonal ice morphology maps. The seasonal ice morphology maps show, in terms of a zonal analysis, regions of statistically uniform ice behavior. The behavioral characteristics of each zone have been described in terms of coastal processes and bathymetric configuration. Based on the combined seasonal morphologies, a zonal analysis of potential hazards related to offshore petroleum development has been made for the study area. The general conclusion is that overall nearshore sea ice behavioral patterns are sufficiently similar from year to year, that 5 years' data can yield some predictability in terms of offshore sea ice hazards to oil and gas development. The implications are that geographical zones of different design and construction criteria can be established in the offshore areas based on the probability of damage to the structure by adverse ice conditions and the relative risk imposed to the adjacent eco-systems.
Consequences of Disk Scale Height on LISA Confusion Noise from Close White Dwarf Binaries

Gravitational radiation from the Galactic population of close white dwarf binaries (CWDBs) is expected to produce a confusion-limited signal at the lower end of the sensitivity band of the Laser Interferometer Space Antenna (LISA). The canonical scale height of the disk population has been taken to be 90 pc for most studies of the nature of this confusion-limited signal. This estimate is probably too low, and the consequences of a more realistic scale height are investigated with a model of the LISA signal due to populations of CWDBs with different scale heights. If the local space density of CWDBs is held constant, increasing the scale height results in both an increase in the overall strength of the confusion-limited signal as well as an increase in the frequency at which the signals become individually resolvable. If the total number of binaries is held constant, increasing the scale height results in a reduction of the number of expected bright signals above the confusion-limited signal at low frequencies. We introduce an estimator for comparing this transition frequency that takes into account the signal spreading at higher frequencies.
Compensation of time-dependent persistent current effects in superconducting synchrotrons.

Persistent currents in superconducting accelerator magnets are caused by the magnetization of the superconducting filaments in the field of the magnet itself. The magnetized filaments create additional field distortions which can have an important effect on beam dynamics. During the initial operation of the Tevatron as a colliding beam accelerator, the chromaticities at the injection energy were found to be time dependent, leading to instabilities and particle loss during injection and at the start of acceleration. Laboratory measurements on single Tevatron dipole magnets indicated that these effects were due to time-dependent persistent current phenomena. Using additional laboratory measurements and beam observations, we have developed a set of procedures to compensate the time-dependent chromaticities due to the persistent currents. The application of these procedures has eliminated all problems caused by time-dependent persistent current effects. We will discuss the general problem of persistent current distortions in superconducting accelerators, and, then, the laboratory measurements, the beam observations, and the successful implementation of the correction schemes. While these procedures have worked well, they have limitations which will be discussed, as well as possible future improvements and implications for future projects.
Diastereo- and enantioselective anti-alkoxyallylation employing allylic gem-dicarboxylates as allyl donors via iridium-catalyzed transfer hydrogenation.

Enantioselective transfer hydrogenation of gem-dibenzoate 1e in the presence of aromatic, α,β-unsaturated, or aliphatic aldehydes 2a−i mediated by isopropyl alcohol and employing a cyclometalated iridium C,O-benzoate derived from allyl acetate, 4-cyano-3-nitrobenzoic acid, and (R)-SEGPHOS delivers products of alkoxyallylation 3a−i, 4a, 4e, 4f, and 4i in good isolated yields (62−82%) with good to excellent diastereoselectivities (7:1 to 18:1 dr) and exceptional enantioselectivities (90−99% ee). This protocol provides an alternative to the use of premetalated nucleophiles in carbonyl alkoxyallylation.
MASSCLEAN—MASSIVE CLUSTER EVOLUTION AND ANALYSIS PACKAGE: DESCRIPTION AND TESTS

We present MASSCLEAN, a new, sophisticated and robust stellar cluster image and photometry simulation package. This visualization tool is able to create color-magnitude diagrams (CMDs) and standard FITS images in any of the traditional optical and near-infrared bands based on cluster characteristics input by the user, including but not limited to distance, age, mass, radius, and extinction. At the limit of very distant, unresolved clusters, we have checked the integrated colors created in MASSCLEAN against those from other simple stellar population models with consistent results. We have also tested models that provide a reasonable estimate of the field star contamination in images and CMDs. We demonstrate the package by simulating images and CMDs of well-known massive Milky Way clusters and compare their appearance to real data. Because the algorithm populates the cluster with a discrete number of tenable stars, it can be used as part of a Monte Carlo Method to derive the probabilistic range of characteristics (integrated colors, for example) consistent with a given cluster mass and age. Our simulation package is available for download and will run on any standard desktop running UNIX/Linux. Full documentation on installation and its use is also available. Finally, a Web-based version of MASSCLEAN, which can be immediately used and is sufficiently adaptable for most applications, is available through a Web interface.
A Model of Currency Depreciation and the Debt-Inflation Spiral

Abstract This paper shows how a government that cannot make credible policy commitments might manage its exchange rate and fiscal stance in a world of rational expectations. The dynamic-game model developed here potentially can generate diverse patterns of macroeconomic behavior, patterns that differ as a result of assumed differences in government objectives. Under some types of government, the ongoing strategic interaction between the public and private sectors leads to a disinflationary outcome. Other governments may push the economy into a spiral of rising debt and inflation.
Single-step controlled-NOT logic from any exchange interaction

A self-contained approach to studying the unitary evolution of coupled qubits is introduced, capable of addressing a variety of physical systems described by exchange Hamiltonians containing Rabi terms. The method automatically determines both the Weyl chamber steering trajectory and the accompanying local rotations. Particular attention is paid to the case of anisotropic exchange with tracking controls, which is solved analytically. It is shown that, if computational subspace is well isolated, any exchange interaction can always generate high fidelity, single-step controlled-NOT (CNOT) logic, provided that both qubits can be individually manipulated. The results are then applied to superconducting qubit architectures, for which several CNOT gate implementations are identified. The paper concludes with consideration of two CNOT gate designs having high efficiency and operating with no significant leakage to higher-lying noncomputational states.
THE NATIONAL REGISTRY OF DRUG‐INDUCED OCULAR SIDE EFFECTS

The National Registry of Drug-induced Ocular Side Effects is an international information centre for ocular toxicology. The Registry collects case reports of drug-induced ocular side effects from physicians and other national registries, and surveys the world literature for drug-related ocular events. Possible adverse drug associations can be identified in this system, and cause-and-effect relationships may on occasion be proven. Functions of this Registry include increasing ophthalmic awareness of human ocular toxicology, and promoting continuation of contributions to decrease the delay between recognition of a possible adverse drug reaction and the actual reporting of it in the literature.
Unusual 180° P−O−P Bond Angles in ZrP2O7

The structure of cubic ZrP2O7 at room temperature has been solved and refined using a combination of modeling and high-resolution neutron powder diffraction data. The cell edge is 24.74 A, the space group is Pa3, and Z is 108. For those P2O7 units not on a 3-fold axis, the P−O−P angles range from 134° to 162°. Two crystallographically distinct P2O7 groups are on three fold axes with P−O−P angles thus constrained to be 180° on average. The structure of cubic ZrP2O7 was also refined from data taken at 227, 290, 371, 435, and 610 °C. The 3 × 3 × 3 superstructure present at room temperature disappears at about 290 °C, and all P−O−P angles of P2O7 are then constrained by symmetry to be 180° on average. The exceptionally low thermal expansion shown by ZrP2O7 above 290 °C is likely related to the unusual P−O−P angle.
Nonconvex cases for carpenter's rulers

We consider the carpenter's ruler folding problem in the plane, i.e., finding a minimum area shape with diameter 1 that accommodates foldings of any ruler whose longest link has length 1. An upper bound of π / 3 - 3 / 4 = 0.614 ? and a lower bound of 10 + 2 5 / 8 = 0.475 ? are known for convex cases. We generalize the problem to simple nonconvex cases: in this setting we improve the upper bound to 0.583 and establish the first lower bound of 0.073. A variation is to consider rulers with at most k links. The current best convex upper bounds are (about) 0.486 for k = 3 , 4 and π / 6 = 0.523 ? for k = 5 , 6 . These bounds also apply to nonconvex cases. We derive a better nonconvex upper bound of 0.296 for k = 3 , 4 .
Melting as a dislocation-mediated phase transition

We present a theory of the melting of elements as a dislocation-mediated phase transition. We model dislocations near the melt as noninteracting closed loops on a lattice. In this framework we derive simple expressions for the melting temperature and latent heat of fusion that depend on the dislocation density at melt. We use experimental data for more than half the elements in the periodic table to determine the dislocation density from both relations. Melting temperatures yield a dislocation density of $(0.61\ifmmode\pm\else\textpm\fi{}{0.20)b}^{\ensuremath{-}2},$ in good agreement with the density obtained from latent heats, $(0.66\ifmmode\pm\else\textpm\fi{}{0.11)b}^{\ensuremath{-}2},$ where b is the length of the smallest perfect-dislocation Burgers vector. Melting corresponds to the situation where, on average, half of the atoms are within a dislocation core.
Multiscale Modeling of Recrystallization

We propose a multi length scale approach to modeling recrystallization which links a dislocation model, a cell growth model and a macroscopic model. Although this methodology and linking framework will be applied to recrystallization, it is also applicable to other types of phase transformations in bulk and layered materials. Critical processes such as the dislocation structure evolution, nucleation, the evolution of crystal orientations into a preferred texture, and grain size evolution all operate at different length scales. In this paper we focus on incorporating experimental measurements of dislocation substructures, rnisorientation measurements of dislocation boundaries, and dislocation simulations into a mesoscopic model of cell growth. In particular, we show how feeding information from the dislocation model into the cell growth model can create realistic initial microstructure.
Computation of the Weight Function from a Stress Intensity Factor

A simple representation for the crack-face displacement is employed to compute a weight function solely from stress intensity factors for a reference loading configuration. Crack face displacements given by the representation are shown to be in good agreement with analytical results for cracked tensile strips, and stress intensity factors computed from the weight function agree well with those for edge cracks in half planes, radial cracks from circular holes, and radially cracked rings. The technique involves only simple quadrature and its efficacy is demonstrated by the example computations. The weight function for a corner crack in an LMFBR hexagonal sub-assembly duct is constructed from stress-intensity-factor results for the uniformly over-pressurized case, and it is shown how this may be used to determine the stress intensity factors.
The integral cohomology of the Bianchi groups

We calculate the integral cohomology ring structure for various members of the Bianchi group family. The main tools we use are the Bockstein spectral sequence and a long exact sequence derived from Bass-Serre theory.
A chip-scale, telecommunications-band frequency conversion interface for quantum emitters

We describe a chip-scale, telecommunications-band frequency conversion interface designed for low-noise operation at wavelengths desirable for common single photon emitters. Four-wave-mixing Bragg scattering in silicon nitride waveguides is used to demonstrate frequency upconversion and downconversion between the 980 nm and 1550 nm wavelength regions, with signal-to-background levels > 10 and conversion efficiency of ≈ −60 dB at low continuous wave input pump powers ( 25 % in existing geometries. Finally, we present waveguide designs that can be used to connect shorter wavelength (637 nm to 852 nm) quantum emitters with 1550 nm.
You can’t teach speed: sprinters falsify the deliberate practice model of expertise

Many scientists agree that expertise requires both innate talent and proper training. Nevertheless, the highly influential deliberate practice model (DPM) of expertise holds that talent does not exist or makes a negligible contribution to performance. It predicts that initial performance will be unrelated to achieving expertise and that 10 years of deliberate practice is necessary. We tested these predictions in the domain of sprinting. In Studies 1 and 2 we reviewed biographies of 15 Olympic champions and the 20 fastest American men in U.S. history. In all documented cases, sprinters were exceptional prior to initiating training, and most reached world class status rapidly (Study 1 median = 3 years; Study 2 = 7.5). In Study 3 we surveyed U.S. national collegiate championships qualifiers in sprinters (n = 20) and throwers (n = 44). Sprinters recalled being faster as youths than did throwers, whereas throwers recalled greater strength and throwing ability. Sprinters' best performances in their first season of high school, generally the onset of formal training, were consistently faster than 95-99% of their peers. Collectively, these results falsify the DPM for sprinting. Because speed is foundational for many sports, they challenge the DPM generally.
Regioselective Formation of 1,1-Disubstituted Allenylsilanes via Cross-Coupling Reactions of 3-Tri-n-butylstannyl-1-trimethylsilyl-1-propyne

The regioselective Stille cross-coupling reactions of 3-tri-n-butylstannyl-1-trimethylsilyl-1-propyne demonstrate isomerization following the initial transmetalation step resulting in allenyl palladium intermediates for reductive coupling to yield conjugated 1,1-disubstituted allenylsilanes.
Asymptotic limits of video signal processing architectures

This paper analyzes the effects of technology scaling on video signal processing (VSP) architectures. We evaluate the processor, the memory, and the interconnect delays in terms of sophisticated delay models (that take into account deep-sub-micron device characteristics) and study how the response times of these logic components are affected when the feature sizes scale down. Equations for gate and interconnect delays, as functions of process scaling, are derived and the impact of these results examined in the context of heavily pipelined architectures, architectures featuring crossbar interconnection networks, and architectures whose performance is dominated by memory bandwidth. Architectural parameters such as clock skew, clock frequency, memory interleaving, memory efficiency, and average waiting times are analyzed in the light of the scaling behavior of the gate and the interconnect delays. In the context of scaling of interconnection lines and memory modules, we also highlight how the transmission-line characteristics of long lines are affected by technology scaling and how the delay associated with the memory subsystem-both the memory interleaving and the memory interconnect network-can be a potential bottleneck for the system's speed of operation. It is likely that sophisticated compilation and scheduling techniques must be employed along with architectural optimizations to achieve maximum system performance and ensure that the final hardware-software configuration does not overload the processor-memory communication.
Novel palladium (II) mediated reactions of N-hydroxy-β-lactams

Abstract The attempted cyclization of an N-hydroxy-β-lactam onto an olefin activated with palladium (II) resulted in the formation of two interesting products, both of which suggest that the palladium acted as a Lewis acid.
Recent Advances in the Metal-Catalyzed Ring Expansions of Three- and Four-Membered Rings

New catalytic ring-expansion reactions of strained ring (hetero- and carbocyclic) substrates reported in the last six years (2006–2012) are presented. As evident from the diversity of new approaches, this is a vibrant area of research. Metals ranging from magnesium to gold have been used as catalysts. Some of these reactions allow access to enantioenriched products by employing catalysts decorated with chiral organic motifs (primarily C-2 symmetric).
Elemental Abundances in Ngc 3516

We present Reflection Grating Spectrometer data from an XMM-Newton observation of the Seyfert 1 galaxy NGC 3516, taken while the continuum source was in an extremely low flux state. This observation offers a rare opportunity for a detailed study of emission from a Seyfert 1 galaxy as these are usually dominated by high nuclear continuum levels and heavy absorption. The spectrum shows numerous narrow emission lines (FWHM approximately less than 1300 kilometers per second) in the 0.3 - 2 keV range, including the H-like lines of C, N, and O and the He-like lines of N, O and Ne. The emission-line ratios and the narrow width of the radiative recombination continuum of CVI indicate that the gas is photoionized and of fairly low temperature (kT approximately less than 0.01 keV). The availability of emission lines from different elements for two iso-electronic sequences allows us to constrain the element abundances. These data show that the N lines are far stronger than would be expected from gas of solar abundances. Based on our photoionization models we find that nitrogen is overabundant in the central regions of the galaxy, compared to carbon, oxygen and neon by at least a factor of 2.5. We suggest that this is the result of secondary production of nitrogen in intermediate mass stars, and indicative of the history of star formation in NGC 3516.
Aspects of the optimal management of cyclical ecological–economic systems

Abstract We now know that from a functional standpoint, jointly determined ecological–economic systems (ecosystems) cycle over time. However, because this recognition has been recent, the ecological economics literature contains very few formal studies of the management of cyclical ecosystems. Consequently, the objective of this paper is to use renewal theory to examine two ways of analyzing the optimal management of cyclical ecosystems.
Nonlinear Shock Acceleration beyond the Bohm Limit

We suggest a physical mechanism whereby the acceleration time of cosmic rays (CRs) by shock waves can be significantly reduced. This creates the possibility of particle acceleration beyond the knee energy at ~1015 eV. The acceleration results from a nonlinear modification of the flow ahead of the shock supported by particles already accelerated to the knee momentum at p ~ p*. The particles gain energy by bouncing off converging magnetic irregularities frozen into the flow in the shock precursor and not so much by recrossing the shock itself. The acceleration rate is thus determined by the gradient of the flow velocity and turns out to be formally independent of the particle mean free path (mfp). The velocity gradient is, in turn, set by the knee particles at p ~ p* as having the dominant contribution to the CR pressure. Since it is independent of the mfp, the acceleration rate of particles above the knee does not decrease with energy, unlike in the linear acceleration regime. The reason for the knee formation at p ~ p* is that particles with p > p* are effectively confined to the shock precursor only while they are within limited domains in the momentum space, while other particles fall into "loss islands," similar to the "loss cone" of magnetic traps. This structure of the momentum space is due to the character of the scattering magnetic irregularities. They are formed by a train of shock waves that naturally emerge either from unstably growing and steepening magnetosonic waves or as a result of acoustic instability of the CR precursor (CRP). These losses steepen the spectrum above the knee, which also prevents the shock width from increasing with the maximum particle energy.
Changes in HIV/AIDS knowledge and testing behavior in Africa: how much and for whom?

Demographic and Health Survey data from nine African countries make it clear that HIV/AIDS prevention knowledge has been increasing. Still, in many cases, fewer than half of adult respondents can identify specific prevention behaviors. Knowledge is lowest in rural areas and among women. HIV testing generally remains rare but is highly variable across countries, likely reflecting differences in the supply of testing services. In most cases, schooling and wealth impacts on prevention knowledge have either been stable or have increased; hence, in the majority of contexts, initial disparities in knowledge by education and wealth levels have persisted or widened.
Electrical Propulsion for Space Missions: Planning Considerations

Abstract Electrical propulsion systems are being proposed for advanced space missions because of their extremely high specific impulse relative to more conventional systems now under development. This paper presents information pertinent to research and development planning relative to electrical propulsion systems. It draws largely from a study made by The RAND Corporation for NASA and summarizes: 1) vehicle weights and costs for advanced space missions utilizing electrical propulsion systems and the competitive nuclear rocket and chemical rocket systems (the manned Mars expedition, lunar logistic transport, and deep space probe missions are explored); 2) the estimated cost and time to develop the electrical propulsion system; and 3) the promise of new technologies. Some of the conclusions are 1) the development cost and time for an electrical propulsion system in the megawatt power class based on current Rankine cycle technology (maximum cycle temperature 2000°F) are estimated at over 3 × 109 dollars and 12 years, respectively; 2) the mission studies revealed no economic or performance advantage sufficiently compelling to warrant the early initiation of a full scale development based on the current Rankine cycle technology; and 3) present emphasis should be placed on a) exploratory engineering studies relating to Rankine, Brayton, and thermionic systems, and b) research on new technologies.
Integrity aspects of a shared data base

A simple model is formulated to represent integrity constraints and to describe the evaluation and enforcement of these constraints in a shared data base environment. The proposed model is applied to define the integrity facilities of a relational data base. This data base consists of a set of base relations, which are presented to the user through application-oriented views. These views are basically joins or projections of the base relations, and the data base is accessed through a language which by referring to predefined views, makes explicit the intentions of application programs. The types of integrity rules incorporated in this system, their description, their evaluation, and the propagation of changes to views into the shared data base, are discussed.
A high-accuracy blackbody for CLARREO

The NASA climate science mission Climate Absolute Radiance and Refractivity Observatory (CLARREO), which is to measure Earth's emitted spectral radiance from orbit for 5 years, has an absolute accuracy requirement of 0.1 K (3σ) at 220 K over most of the thermal infrared. To meet this requirement, CLARREO needs highly accurate on-board blackbodies which remain accurate over the life of the mission. Space Dynamics Laboratory is developing a prototype blackbody that demonstrates the ability to meet the needs of CLARREO. This prototype is based on a blackbody design currently in use, which is relatively simple to build, was developed for use on the ground or on-orbit, and is readily scalable for aperture size and required performance. We expect the CLARREO prototype to have emissivity of ~0.9999 from 1.5 to 50 μm, temperature uncertainties of ~25 mK (3σ), and radiance uncertainties of ~10 mK due to temperature gradients. The high emissivity and low thermal gradient uncertainties are achieved through cavity design, while the SItraceable temperature uncertainty is attained through the use of phase change materials (mercury, gallium, and water) in the blackbody. Blackbody temperature sensor calibration is maintained over time by comparing sensor readings to the known melt temperatures of these materials, which are observed by heating through their melt points. Since blackbody emissivity can potentially change over time due to changes in surface emissivity (especially for an on-orbit blackbody) an on-board means of detecting emissivity change is desired. The prototype blackbody will include an emissivity monitor based on a quantum cascade laser to demonstrate the concept.
Ventral Abdominal Approach for Laparoscopic Cryptorchidectomy in Horses

Objective—To report a ventral abdominal approach and a ligating loop technique for laparoscopic cryptorchidectomy in horses. Study Design—Prospective. Sample Population—Six horses, aged 1 to 5 years, with retained testes. Methods—One laparoscopic portal and three to four instrument portals were used for ventral abdominal laparoscopic cryptorchidectomy. Laparoscopic instruments were used to maneuver and secure the testis through a ligating loop (modified Roeder knot) that was secured from outside the abdominal cavity. Only minimal enlargement of one instrument portal was used to remove the testicle. Results—Three horses were bilateral cryptorchids, and three were unilateral (left side, two; right side, one) cryptorchids. Operative time, defined as the time from laparoscope insertion to removal, ranged from 20 to 25 minutes for unilateral cryptorchids and from 40 to 50 minutes for bilateral cryptorchids. Conclusions—The reported technique allowed decreased tension on the tissues during ligation and removal of the testis from the peritoneal cavity. Improved observation of the abdominal cavity, ligation security, shortened patient confinement time, and minimally invasive technique are all considered to be benefits of laparoscopic cryptorchidectomy. Clinical Relevance—Direct observation of retained testes and intraabdominal castration are distinct advantages of the use of laparoscopy in horses that have had previous unsuccessful surgical attempts, horses with unknown histories that have retained testicular tissue, or bilateral abdominal cryptorchids.
Recovering a boundary-level structural description from dynamic stereo

Abstract We present a stereo algorithm to recursively compute a boundary-level structural description of a static scene, from a sequence of dynamic stereo images. This algorithm is based on connected line segments as the basic match primitive, which yields a description composed primarily of boundaries of objects in the scene. The algorithm is integrated into a dynamic stereo vision system to compute and incrementally refine such a structural description recursively, using belief measures. The approach is illustrated with a real dynamic stereo sequence.
Interferometric observations of explosive variables: V838 Mon, Nova Aql 2005, and RS Oph

During the last two years we have used the Palomar Testbed Interferometer to observe several explosive variable stars, including V838 Monocerotis, V1663 Aquilae and recently RS Ophiuchi. We observed V838 Monocerotis approximately 34 months after its eruption, and were able to resolve the ejecta. Observations of V1663 Aql were obtained starting 9 days after peak brightness and continued for 10 days. We were able to resolve the milliarcsecond-scale emission and follow the expansion of the nova photosphere. When combined with radial-velocity information, these observations can be used to infer the distance to the nova. Finally we have resolved the recurrent nova RS Oph and can draw some preliminary conclusions regarding the emission morphology.
Some reflections on early history

The ideas and developments reviewed briefly are mainly from six sources: (1) the M.I.T. Lincoln Laboratory during the middle and late 1950s, (2) Bolt Beranek and Newman in 1957-1962, (3) the ARPA program in 1962-1964, (4) IBM Research in 1964-1966, (5) Ivan Sutherland's lab at Harvard in 1967, and (6) Project MAC at M.I.T. in 1968-1972.For instance, there were (1) cloud filter stations with light guns and light pens, (2) a single 1024x1024 scope display time-shared four ways and a workstation for studying technical documents, (3) Rand tablets. Teagher tables, and Bernstein's horizontal text-editing display onto which both the human editor and the computer editor could write (and understand each other), (4) a computer system especially for computer-based education and a powerful vector graphics display system, (5) a PDP-1-based, single-user workstation with four display screens, a paper tape unit, a magnetic tape unit, a printer, and the beginnings of Sutherland's virtual space displays, and (6) graphics over the ARPANET and a multi-window workstation based on the Evans and Sutherland LDS-1.One of the key insights to be offered explains why workstations have vertical instead of horizontal (desk-like) display surfaces. Part of the plot is that, when, in the 50s or 60s, a cathode-ray tube was mounted face-up, some of the phosphor fell down onto the electron gun and caused a short circuit. Another part is that Fredkin and DEC simply got mixed up about which way the PDP-1 display ought to swivvel.