cssi/SciSciGPT-SciSciNet huggingface dataset:
Extreme genetic code optimality from a molecular dynamics calculation of amino acid polar requirement

A molecular dynamics calculation of the amino acid polar requirement is used to score the canonical genetic code. Monte Carlo simulation shows that this computational polar requirement has been optimized by the canonical genetic code, an order of magnitude more than any previously known measure, effectively ruling out a vertical evolution dynamics. The sensitivity of the optimization to the precise metric used in code scoring is consistent with code evolution having proceeded through the communal dynamics of statistical proteins using horizontal gene transfer, as recently proposed. The extreme optimization of the genetic code therefore strongly supports the idea that the genetic code evolved from a communal state of life prior to the last universal common ancestor.
Asymmetric epoxidation using hydrogen peroxide (H2O2) as primary oxidant

Abstract High enantioselectivities have been obtained for asymmetric epoxidation of olefins using a fructose-derived chiral ketone as catalyst and hydrogen peroxide as primary oxidant.
Radio detections of stellar winds from the Pistol Star and other stars in the galactic center Quintuplet cluster

Very Large Array images of the Sickle and Pistol H II regions near the Galactic center at 8.3 and 4.9 GHz reveal six point sources in the region where the dense Quintuplet stellar cluster is located. The spectral indices of five of these sources between 6 and 3.6 cm have values of α = 0.5 to 0.8 (where Sν ∝ να), consistent with the interpretation that the radio sources correspond to ionized stellar winds of the massive stars in this cluster. The radio source associated with the Pistol star shows α = -0.4 ± 0.2, consistent with a flat or slightly nonthermal spectrum.
Photochemical activation of trimethylsilylmethyl allylic sulfones for intramolecular 4+3 cycloaddition

Abstract Irradiation of allylic sulfones 4–7 results in the formation of 4+3 cycloadducts 8–11 . Although the yields are poor, this represents the first apparent photochemical generation of acyclic allylic cations for 4+3 cycloadditions. Mechanistically, this process is interpreted as an electron transfer process to form an internal radical cation/radical anion reactive intermediate. This eliminates p-tolylsulfinate anion to form an allylic cation which undergoes an intramolecular 4+3 cycloaddition.
Observation of bose-einstein condensation of molecules

We have observed Bose-Einstein condensation of molecules, created from a spin mixture of fermionic 6Li atoms. The condensate realizes the limit of tightly bound fermion pairs in the crossover between BCS and BEC superfluidity
Alkyne Metathesis with Simple Catalyst Systems: Efficient Synthesis of Conjugated Polymers Containing Vinyl Groups in Main or Side Chain

The synthesis of novel conjugated polymers by acyclic diyne metathesis (ADIMET) is reported. These polymers are hybrids between poly(p-phenylenevinylene) and poly(p-phenyleneneethynylene) (PPE). They contain phenylene, ethynylene, and vinylene groups (⋮PhPh, PPVE). Simple in situ catalysts formed from Mo(CO)6 and 4-chlorophenol were used to metathesize the dipropynyl(tetraalkyl)stilbene monomers. The monomers are made by a combination of Horner reactions and Heck-type couplings. The PPVEs form in high yields and are structurally defined. They show degrees of polymerization (Pn) of 30−220 repeating units (i.e. 60−450 benzene rings), demonstrating that the presence of the double bonds does not interfere with alkyne metathesis. The PPVEs were structurally characterized by XRD and electron microscopy. They show fibrillar and network-type morphologies, which should make them interesting for applications in molecular electronics. Solid samples of PPVEs display powder XRD patterns almost identical to those of th...
Distributed Detection in Coexisting Large-Scale Sensor Networks

This paper considers signal detection in coexisting wireless sensor networks. We characterize the aggregate signal and interference from a Poisson random field of nodes and define a binary hypothesis testing problem to detect a signal in the presence of interference. For the testing problem, we introduce the maximum likelihood (ML) detector and simpler alternatives. The proposed mixed-fractional lower order moment detector is computationally simple and close to the ML performance, and robust to estimation errors in system parameters. We also derived asymptotic theoretical performances for the proposed simple detectors. Monte-Carlo simulations are used to supplement our analytical results and compare the performance of the receivers.
Spatial analysis of highway incident durations in the context of Hurricane Sandy

The objectives of this study are (1) to develop an incident duration model which can account for the spatial dependence of duration observations, and (2) to investigate the impacts of a hurricane on incident duration. Highway incident data from New York City and its surrounding regions before and after Hurricane Sandy was used for the study. Moran's I statistics confirmed that durations of the neighboring incidents were spatially correlated. Moreover, Lagrange Multiplier tests suggested that the spatial dependence should be captured in a spatial lag specification. A spatial error model, a spatial lag model and a standard model without consideration of spatial effects were developed. The spatial lag model is found to outperform the others by capturing the spatial dependence of incident durations via a spatially lagged dependent variable. It was further used to assess the effects of hurricane-related variables on incident duration. The results show that the incidents during and post the hurricane are expected to have 116.3% and 79.8% longer durations than those that occurred in the regular time. However, no significant increase in incident duration is observed in the evacuation period before Sandy's landfall. Results of temporal stability tests further confirm the existence of the significant changes in incident duration patterns during and post the hurricane. Those findings can provide insights to aid in the development of hurricane evacuation plans and emergency management strategies.
Performance of a bell-curve based evolutionary optimization algorithm

An evolutionary search strategy utilizing two normal distributions to generate children is presented. This Bell-Curve Based (BCB) evolutionary algorithm is similar in spirit to (μ+μ) evolutionary strategies but with fewer parameters to adjust. Extensive tests regarding the sensitivity of BCB parameters to performance are provided. The test suite includes continuous variable constrained hub design problems, mixed discrete and continuous variable constrained hub design problems, and an unconstrained highly multimodal discrete optimization problem.
Platelet function testing in cardiovascular diseases.

(2005). Platelet function testing in cardiovascular diseases. Hematology: Vol. 10, No. sup1, pp. 132-137.
Intramolecular oxidative-cycloaddition of dihydropyrazolones

Abstract The hitherto unknown intramolecular cycloaddition reaction of azo dienophiles, as outlined in Scheme I below, is described.
Properties of Stars in the Subaru Deep Field

We investigate the properties of objects in the Subaru Deep Field (SDF), using public catalogs constructed from images in several optical passbands. Using a small subset of objects most likely to be stars, we construct a stellar locus in threedimensional color space. We then compare the position of all objects relative to this locus to create larger samples of stars in the SDF with rough spectral types. The number counts of stars defined in this way are consistent with those of current models of the Galaxy.
Molecular solvent-dynamical effects on activated electron-transfer kinetics: How important is solvent friction?

Abstract The likely extent of retardation exerted by solvent friction upon the rates of activated electron-transfer (ET) processes is explored and evaluated with reference to some extant solvent-dependent data for metallocene ET self exchanges. Barrier-crossing frequencies extracted from the experimental kinetic and barrier data for suitably adiabatic reactions are compared with solvent inertial frequencies (i.e. the zero-friction limit) as estimated from currently available analytic expressions. The additional extent of rate retardation seen in passing from low-friction to ostensibly strongly overdamped solvents, as deduced in this manner, is seen to be muted substantially in comparison with the predictions of conventional Debye-continuum approaches, although following a solvent functionality that is nevertheless roughly in accord with the latter. The likely importance of more rapid dynamics associated with short-range (molecular) solvation is addressed in the light of these findings.
D-bundles and integrable hierarchies

Contents1. Introduction 21.1. A Brief History of the KP/CM Correspondence 21.2. Background 31.3. D-Bundles 41.4. D-Bundles and KP Hierarchies 61.5. Fourier Transform and Moduli of D-Bundles 81.6. Further Directions 81.7. Contents 91.8. Acknowledgments 92. Background Material 92.1. Background on Cubic Curves 92.2. Calogero-Moser Systems and Spectral Curves 122.3. The KP Hierarchy 163. D-Bundles 193.1. D-Bundles on Curves 193.2. Moduli of D-Bundles and Calogero-Moser Spectral Sheaves 203.3. The Ad`elic Grassmannian 213.4. Local D-Bundles and the Sato Grassmannian 233.5. Lax Operators and Micro-Opers 253.6. Flows of the KP and CM Hierarchies 274. Fourier Transform for Cubic Curves 294.1. Fourier Equivalence for Weierstrass Cubics 294.2. Fourier Transform of Torsion-Free Sheaves 304.3. Fourier Equivalence for D
Robust decision analysis for environmental management of groundwater contamination sites

In contrast to many other engineering fields, the uncertainties in subsurface processes (e.g., fluid flow and contaminant transport in aquifers) and their parameters are notoriously difficult to observe, measure, and characterize. This causes severe uncertainties that need to be addressed in any decision analysis related to optimal management and remediation of groundwater contamination sites. Furthermore, decision analyses typically rely heavily on complex data analyses and/or model predictions, which are often poorly constrained as well. Recently, we have developed a model-driven decisionsupport framework (called MADS; http://mads.lanl.gov) for the management and remediation of subsurface contamination sites in which severe uncertainties and complex physics-based models are coupled to perform scientifically defensible decision analyses. The decision analyses are based on Information Gap Decision Theory (IGDT). We demonstrate the MADS capabilities by solving a decision problem related to optimal monitoring network design.
Hydrodynamic Models of Line-Driven Accretion Disk Winds III: Local Ionization Equilibrium

We present time-dependent numerical hydrodynamic models of line-driven accretion disk winds in cataclysmic variable systems and calculate wind mass-loss rates and terminal velocities. The models are 2.5-dimensional, include an energy balance condition with radiative heating and cooling processes, and includes local ionization equilibrium introducing time dependence and spatial dependence on the line radiation force parameters. The radiation field is assumed to originate in an optically thick accretion disk. Wind ion populations are calculated under the assumption that local ionization equilibrium is determined by photoionization and radiative recombination, similar to a photoionized nebula. We find a steady wind flowing from the accretion disk. Radiative heating tends to maintain the temperature in the higher density wind regions near the disk surface, rather than cooling adiabatically. For a disk luminosity L (sub disk) = solar luminosity, white dwarf mass M(sub wd) = 0.6 solar mass, and white dwarf radii R(sub wd) = 0.01 solar radius, we obtain a wind mass-loss rate of M(sub wind) = 4 x 10(exp -12) solar mass yr(exp -1) and a terminal velocity of approximately 3000 km per second. These results confirm the general velocity and density structures found in our earlier constant ionization equilibrium adiabatic CV wind models. Further we establish here 2.5D numerical models that can be extended to QSO/AGN winds where the local ionization equilibrium will play a crucial role in the overall dynamics.
THE VALUE OF EXPERIENTIAL LEARNING BY ORGANIZATIONS: EVIDENCE FROM INTERNATIONAL JOINT VENTURES

We use a sample of international joint venture announcements to test the hypothesis that organizations learn from experience, such that prior learning enhances the value of later ventures. We find that experience with ventures in the same foreign location, as well as experience with international joint ventures in general, is valued by the market. In contrast, experience in the same type of joint venture activity does not add any incremental value. These findings suggest the market recognizes and values some, although not all, forms of organizational learning.
Winslow Smoothing on Two-Dimensional Unstructured Meshes

The Winslow equations from structured elliptic grid generation are adapted to smoothing of two-dimensional unstructured meshes using a finite difference approach. We use a local mapping from a uniform N-valent logical mesh to a local physical subdomain. Taylor Series expansions are then applied to compute the derivatives which appear in the Winslow equations. The resulting algorithm for Winslow smoothing on unstructured triangular and quadrilateral meshes gives generally superior qualilty than traditional Laplacian smoothing, while retaining the resistance to mesh folding on structured quadrilateral meshes.
On f-core equivalence with general widespread externalities

This paper partially extends the f-core equivalence theorem of Hammond, Kaneko and Wooders (1989) for continuum economies with widespread externalities — i.e., those over which each individual has negligible control. Externalities need not result directly from trading activities. Neither free disposal of divisible goods nor monotone preferences are assumed. Instead, a slightly strengthened form of local non-satiation suffices. However, in general it is proved only that any f-core allocation is a compensated Nash- Walrasian equilibrium. Finally, the proof uses an elementary argument which does not rely on Lyapunov's theorem or convexity of the integral of a correspondence w.r.t. a non-atomic measure.
Instrumentation for reflectance spectroscopy and microspectroscopy with application to astrobiology

We present instrument concepts for in-situ reflectance spectroscopy over a spatial resolution range from several meters to tens of μm. These have been adapted to the low mass and power requirements of rover or similar platforms. Described are a miniaturized imaging spectrometer for rover mast, a combined mast and arm point spectrometer, and an imaging microspectrometer for the rover arm.
Myosin-ATPase fibre typing of chemically skinned muscle fibres.

The efficacy of myosin (M)-ATPase fibre typing to differentiate fibre types in chemically (EGTA) skinned muscle fibres was investigated. Cryosections or single fibres from isolated bundles of chemically skinned rat extensor digitorum longus (EDL) and soleus (SOL) muscles were stained for M-ATPase activity. The results indicate that two major fibre types (type I and II, Brooke & Kaiser, 1970) can be indentified, as well as subgrouping of the type II fibres into types IIa and IIb. Thus, chemically skinning muscle fibres appears to have no detrimental effects on subsequent M-ATPase fibre typing.
Extreme value statistics in silicon photonics

We show that fluctuations of Raman amplified pulses, in the presence of a noisy pump, follow extreme value statistics, and provide mathematical insight into the origin of this perplexing behavior.
The Label Says

Labeling equipment is an effective method of alerting personnel about shock and arc-flash hazards as well as providing details of necessary protective clothing and procedures. Since arc-flash labeling is intended to protect the worker, it is particularly helpful to consider the various ways in which labeling can go wrong. It is in the best interests of all to avoid any situation that could lead to either a false sense of security or excessive personal protective equipment (PPE). This is a real-life collection of examples from facilities having arc-flash labeling programs in which corrections were needed to the labels, personnel training, and maintenance.
Palladium/imidazolium salt catalyzed coupling of aryl halides with hypervalent organostannates.

A Pd(OAc)2/imidazolium chloride system has been used to mediate the catalytic cross-coupling of aryl halides with organostannanes. The imidazolium salt IPr·HCl (IPr = 1,3-bis(2,6-diisopropylphenyl) imidazol-2-ylidene) in combination with TBAF (nBu4NF) was found to be most effective for the cross-coupling of aryl bromides and electron-deficient aryl chlorides with aryl and vinyl stannanes.
Divergence-free adaptive mesh refinement for Magnetohydrodynamics

Abstract Several physical systems, such as nonrelativistic and relativistic magnetohydrodynamics (MHD), radiation MHD, electromagnetics, and incompressible hydrodynamics, satisfy Stoke's law type equations for the divergence-free evolution of vector fields. In this paper we present a full-fledged scheme for the second-order accurate, divergence-free evolution of vector fields on an adaptive mesh refinement (AMR) hierarchy. We focus here on adaptive mesh MHD. However, the scheme has applicability to the other systems of equations mentioned above. The scheme is based on making a significant advance in the divergence-free reconstruction of vector fields. In that sense, it complements the earlier work of D. S. Balsara and D. S. Spicer (1999, J. Comput. Phys. 7 , 270) where we discussed the divergence-free time-update of vector fields which satisfy Stoke's law type evolution equations. Our advance in divergence-free reconstruction of vector fields is such that it reduces to the total variation diminishing (TVD) property for one-dimensional evolution and yet goes beyond it in multiple dimensions. For that reason, it is extremely suitable for the construction of higher order Godunov schemes for MHD. Both the two-dimensional and three-dimensional reconstruction strategies are developed. A slight extension of the divergence-free reconstruction procedure yields a divergence-free prolongation strategy for prolonging magnetic fields on AMR hierarchies. Divergence-free restriction is also discussed. Because our work is based on an integral formulation, divergence-free restriction and prolongation can be carried out on AMR meshes with any integral refinement ratio, though we specialize the expressions for the most popular situation where the refinement ratio is two. Furthermore, we pay attention to the fact that in order to efficiently evolve the MHD equations on AMR hierarchies, the refined meshes must evolve in time with time steps that are a fraction of their parent mesh's time step. An electric field correction strategy is presented for use on AMR meshes. The electric field correction strategy helps preserve the divergence-free evolution of the magnetic field even when the time steps are subcycled on refined meshes. The above-mentioned innovations have been implemented in Balsara's RIEMANN framework for parallel, self-adaptive computational astrophysics, which supports both nonrelativistic and relativistic MHD. Several rigorous, three-dimensional AMR-MHD test problems with strong discontinuities have been run with the RIEMANN framework showing that the strategy works very well. In our AMR-MHD scheme, the adaptive mesh hierarchy can change in response to discontinuities that move rapidly with respect to the mesh. Time-step subcycling permits efficient processing of the AMR hierarchy. Our AMR-MHD scheme parallelizes very well as shown by Balsara and Norton [8].
Another look at motivating data processing professionals

Motivation is a crucial management issue. The productivity of the U.S. worker is still dropping in the 1980's. The industrial revolution (automation of labor intensive industries) maintained productivity and increased standards of living earlier in this century. The computer revolution has a similar potential for the U.S. and the world. Another look at motivation thus appears indicated. Analysis of the data processing professional's personality profile as developed by recent studies (COU78, COU80, FIT78, LED80) in light of established theories of behavior results in several suggestions for managing computer personnel.
Regioselective syntheses of 5- and 6-aminoanthracene-2,3-dimethanol

Abstract We report the regioselective synthesis of 6-amino-2,3-anthracenedimethanol (2) beginning from commercially available 2,3-dimethylanthraquinone. The more reactive 9- and 10- positions of the anthracene core are masked from electrophilic attack by “protection” of the molecule through formation of its corresponding ethano anthracene (“barrelane”) adduct. Also reported is the synthesis of the corresponding 5-amino isomer (1) from readily available anthraquinone-2,3-dicarboxylic acid.
MINERvA: A Dedicated neutrino scattering experiment at NuMI

MINERvA is a dedicated neutrino cross-section experiment planned for the near detector hall of the NuMI neutrino beam at Fermilab. I summarize the detector design and physics capabilities of the experiment.
Optimal Insurance Contracts When Establishing the Amount of Losses Is Costly

The problem of establishing the amount of losses covered by public and private insurance is often characterized by asymmetric information, in which the claimant already knows the extent of a loss but this can be demonstrated to the insurer only at a cost. It is shown that a simple arrangement, which provides greater coverage whenever individuals demonstrate high losses, gives claimants an excessive incentive to establish the amount of their losses. This paper determines what insurance claims process, consistent with the form typically employed in existing insurance arrangements, is optimal.
The role and timing of palliative medicine consultation for women with gynecologic malignancies: association with end of life interventions and direct hospital costs.

Objective Aggressive care interventions at the end of life (ACE) are reported metrics of sub-optimal quality of end of life care that are modifiable by palliative medicine consultation. Our objective was to evaluate the association of inpatient palliative medicine consultation with ACE scores and direct inpatient hospital costs of patients with gynecologic malignancies.
Preoperative and intraoperative predictors of postoperative acute respiratory distress syndrome in a general surgical population.

Background Acute respiratory distress syndrome (ARDS) is a devastating condition with an estimated mortality exceeding 30%. There are data suggesting risk factors for ARDS development in high-risk populations, but few data are available in lower incidence populations. Using risk-matched analysis and a combination of clinical and research data sets, we determined the incidence and risk factors for the development of ARDS in this general surgical population. Methods We conducted a review of common adult surgical procedures completed between June 1, 2004 and May 31, 2009 using an anesthesia information system. This data set was merged with an ARDS registry and an institutional death registry. Preoperative variables were subjected to multivariate analysis. Matching and multivariate regression was used to determine intraoperative factors associated with ARDS development. Results In total, 50,367 separate patient admissions were identified, and 93 (0.2%) of these patients developed ARDS. Preoperative risk factors for ARDS development included American Society of Anesthesiologist status 3-5 (odds ratio [OR] 18.96), emergent surgery (OR 9.34), renal failure (OR 2.19), chronic obstructive pulmonary disease (OR 2.16), number of anesthetics during the admission (OR 1.37), and male sex (OR 1.65). After matching, intraoperative risk factors included drive pressure (OR 1.17), fraction inspired oxygen (OR 1.02), crystalloid administration in liters (1.43), and erythrocyte transfusion (OR 5.36). Conclusions ARDS is a rare condition postoperatively in the general surgical population and is exceptionally uncommon in low American Society of Anesthesiologists status patients undergoing scheduled surgery. Analysis after matching suggests that ARDS development is associated with median drive pressure, fraction inspired oxygen, crystalloid volume, and transfusion.
Lava shields and fissure eruptions of the Western Volcanic Zone, Iceland: Evidence for magma chambers and crustal interaction

Abstract Volcanic eruptions in Iceland occur either from fissures or central vents (lava shields). Within the post-glacial Western Volcanic Zone, the Thjofahraun fissure-fed lava field and Lambahraun lava shield were both erupted ~ 4000 yrs B.P. with eruptive centers separated by only ~ 25 km. Thjofahraun erupted ~ 1 km3 of pāhoehoe and 'a'ā lava from a 9-km long fissure, whereas the Lambahraun lava shield erupted > 7 km3 of low effusion-rate pāhoehoe. Thjofahraun lavas contain higher K, Rb, Y and Zr, and lower CaO than Lambahraun lavas at the same MgO, with variations broadly consistent with evolution by low-pressure crystal fractionation. Lambahraun spans a larger range of MgO, which generally decreases over time during the eruption. Lambahraun samples with high Al2O3 and low TiO2 and FeO likely reflect up to 15% plagioclase accumulation. In addition, all samples from Lambahraun exhibit increasing CaO and Nb/Zr with decreasing MgO and overall incompatible-element enrichments greater than predicted by crystal fractionation alone. Although the increase in Nb/Zr and other incompatible elements could be explained by gradually more incompatible-element enriched parental magma being supplied to the magmatic system during the course of the Lambahraun eruption, this process requires very small-scale trace element heterogeneities in the mantle that are apparently decoupled from isotopic variations and a systematic relationship between parental magma composition and extent of differentiation. Alternatively, correlations among incompatible element concentration, increasing differentiation and time during the eruption can be related by concurrent wallrock assimilation and crystallization during melt migration through the crust. Geochemical modeling of assimilation of wallrock clinopyroxene concurrent with crystallization of olivine (± plagioclase) effectively reproduces the observed chemical variations of Lambahraun samples. Similar chemical characteristics exist in several other Western Volcanic Zone lava shields but not in fissure eruptions. Magmas that fed fissure eruptions may also have been modified by interaction with the crust prior to aggregation in crustal magma chambers, but the geochemical signature of this process is obscured by magma mixing. In contrast, Icelandic lava shields that preserve deeper level processes may not have developed shallow magma chambers; rather they probably represent slow effusion from magma systems that are continually being recharged and reacting with the crust during the course of their eruptions.
The slowly formed Guiselin brush

We study polymer layers formed by irreversible adsorption from a polymer melt. Our theory describes an experiment which is a "slow" version of that proposed by Guiselin (Europhys. Lett., 17(1992) 225) who considered instantaneously irreversibly adsorbing chains and predicted a universal density profile of the layer after swelling with solvent to produce the "Guiselin brush". Here we ask what happens when adsorption is not instantaneous. The classic example is chemisorption. In this case the brush is formed slowly and the final structure depends on the experiment's duration, tfinal. We find the swollen layer consists of an inner region of thickness z* ~ tfinal−5/3 with approximately constant density and an outer region extending up to height h ~ N5/6 which has the same density decay ~ z−2/5 as for the Guiselin case.
Two classes of perfect graphs

Abstract We present two classes of perfect graphs. The first class is defined through a construction used by Gallai in his investigation of comparability graphs; the second class contains those Berge graphs defined through a forbidden graph on five vertices.
Origin of Heavy Xenon in Meteoritic Diamonds

The neutrino burst from the collapsed core in Type II supernovae liberates free neutrons by nu, nu-prime(n) reactions which drive isotopic abundances several mass steps heavier. The neutron fluence in the He shell, abetted by another burst 10 s later from alpha, n reactions, is about right for rendering Xe-136, the most abundant Xe isotope. The Xe isotopic composition is a good match to Xe-H, the unshielded neutron-rich Xe component abundant in carbonaceous meteorites. The He shell is implicated because it is the only C-rich shell in massive stars that can be expected to condense solid carbon thermally, a requirement for locating the Xe-H in meteoritic diamonds, which are so common as to require an abundant Galactic source of unoxidized carbon.
The Coming of the Second Generation: Immigration and Ethnic Mobility in Southern California:

In a context of widening inequality and governmental persecution of undocumented immigrants, central questions concern the social mobility of new ethnic groups formed as a result of mass migration from Latin America and Asia—especially the growing number of children of immigrants now transitioning to adulthood. This article presents findings from merged samples of two research studies in Southern California, the Children of Immigrants Longitudinal Study (CILS-III) and Immigration and Intergenerational Mobility in Metropolitan Los Angeles (IIMMLA). The focus is on the educational mobility of foreign-parentage (1.5- and second-generation) young adults of Mexican, Salvadoran, Guatemalan, Filipino, Chinese, Korean, Vietnamese, Cambodian, and Laotian origin. The author examines factors that facilitate or derail mobility, including the role of parental human capital and legal/citizenship status, family and neighborhood contexts, early school achievement, acculturation, incarceration, and teenage and nonmarital ...
Highly Enantioselective Direct Conjugate Addition of Ketones to Nitroalkenes Promoted by A Chiral Primary Amine−Thiourea Catalyst

Primary amine−thiourea derivative 1 is an active and highly enantioselective catalyst for the conjugate addition of ketones to nitroalkenes. Broad substrate scope is described, with nitroalkenes be...
Improved flavor symmetry in Kogut-Susskind fermion actions

Abstract We study improved Kogut-Susskind fermion actions focusing on flavor symmetry restoration. Several variants of fat actions suitable for dynamical simulations are considered, including an action with no tree level O(a2) errors. The spectrum of all the pions is computed and used as a measure of flavor symmetry violation. Finally, the Naik term is introduced to restore rotational symmetry.
Improving K-12 pedagogy via a Cloud designed for education

Abstract Cloud computing offers an opportunity to improve K-12 pedagogy with services tailored to teachers’ needs in individual classrooms. The Cloud can deliver services such as remote access to learning tools in a cost effective manner to school systems struggling with reductions in local and state funding. This article explores the distinct ways that a Cloud designed specifically for education can be applied to K-12 education's academic mission. It uses observations from a case study in North Carolina rural high schools using an educational Cloud called the Virtual Computing Lab to access dynamic geometry and algebra software.
One-Centimeter Orbits in Near-Real Time: The GPS Experience on OSTM/JASON-2

The advances in Precise Orbit Determination (POD) over the past three decades have been driven in large measure by the increasing demands of satellite altimetry missions. Since the launch of Seasat in 1978, both tracking-system technologies and orbit modeling capabilities have evolved considerably. The latest in a series of precise (TOPEX-class) altimeter missions is the Ocean Surface Topography Mission (OSTM, also Jason-2). GPS-based orbit solutions for this mission are accurate to 1-cm (radial RMS) within three to five hours of real time. These GPS-based orbit products provide the basis for a near-real time sea-surface height product that supports increasingly diverse applications of operational oceanography and climate forecasting.
Turbulent Supersonic/Hypersonic Heating Correlations for Open and Closed Cavities

Supersonic/hypersonic laminar heating correlations that were developed for damage assessment analysis of atmospheric re-entry vehicles have been modified and extended to cover fully-turbulent conditions over rectangular cavity geometries that are aligned with the local velocity. Turbulent boundary layer properties were computationally determined and used to develop the cavity geometry parametrics and to correlate experimental closed cavity heating data to yield new relationships for the floor-averaged and centerline endwall peakheating augmentation. With the form of the closed-cavity correlations established, historical data were used to develop new correlations for turbulent open-cavity heating.
Executive compensation structure, ownership, and firm performance

Abstract An examination of the executive compensation structure of 153 randomly-selected manufacturing firms in 1979–1980 provides evidence supporting advocates of incentive compensation, and also suggests that the form rather than the level of compensation is what motivates managers to increase firm value. Firm performance is positively related to the percentage of equity held by managers and to the percentage of their compensation that is equity-based. Moreover, equity-based compensation is used more extensively in firms with more outside directors. Finally, firms in which a higher percentage of the shares are held by insiders or outside blockholders use less equity-based compensation.
Development of streamflow projections under changing climate conditions over Colorado River basin headwaters

Abstract. The current drought over the Colorado River Basin has raised concerns that the US Department of the Interior, Bureau of Reclamation (Reclamation) may impose water shortages over the lower portion of the basin for the first time in history. The guidelines that determine levels of shortage are affected by relatively short-term (3 to 7 month) forecasts determined by the Colorado Basin River Forecast Center (CBRFC) using the National Weather Service (NWS) River Forecasting System (RFS) hydrologic model. While these forecasts by the CBRFC are useful, water managers within the basin are interested in long-term projections of streamflow, particularly under changing climate conditions. In this study, a bias-corrected, statistically downscaled dataset of projected climate is used to force the NWS RFS utilized by the CBRFC to derive projections of streamflow over the Green, Gunnison, and San Juan River headwater basins located within the Colorado River Basin. This study evaluates the impact of changing climate to evapotranspiration rates and contributes to a better understanding of how hydrologic processes change under varying climate conditions. The impact to evapotranspiration rates is taken into consideration and incorporated into the development of streamflow projections over Colorado River headwater basins in this study. Additionally, the NWS RFS is modified to account for impacts to evapotranspiration due to changing temperature over the basin. Adjusting evapotranspiration demands resulted in a 6 % to 13 % average decrease in runoff over the Gunnison River Basin when compared to static evapotranspiration rates. Streamflow projections derived using projections of future climate and the NWS RFS provided by the CBRFC resulted in decreased runoff in 2 of the 3 basins considered. Over the Gunnison and San Juan River basins, a 10 % to 15 % average decrease in basin runoff is projected through the year 2099. However, over the Green River basin, a 5 % to 8 % increase in basin runoff is projected through 2099. Evidence of nonstationary behavior is apparent over the Gunnison and San Juan River basins.
A parallel process definition and control system

The purpose of this work is to supply a simple method for definition and efficient control of a network for asynchronous parallel processing.
Conditional sampling for measuring mercury vapor fluxes

Abstract Surface–atmosphere mercury fluxes are difficult to measure accurately. Current techniques include dynamic flux chambers and micrometeorological gradient and aerodynamic approaches, all of which have a number of intrinsic problems associated with them. We have adapted conditional sampling (relaxed eddy accumulation), a micrometeorological technique commonly used to measure other trace gas fluxes, to measure surface–air mercury fluxes. Our initial flux measurement campaign over an agricultural soil consisted of two 1-week measurement periods, and was longer in duration than previously reported mercury flux measurement periods. Fluxes during both measurement periods ranged between 190.5 (evolution) and –91.7 ng m −2 h −1 (deposition) with an average evolution of 9.67 ng m −2 h −1 . The data showed significant diurnal trends, weakly correlated with shallow soil temperatures and solar radiation. This initial trial run indicates that conditional sampling has much promise for the accurate quantification of both short and long-term mercury fluxes.
Effective diffusion in laminar convective flows

The effective diffusion coefficient D* of a passive component, such as test particles, dye, temperature, magnetic flux, etc., is derived for motion in periodic two‐dimensional incompressible convective flow with characteristic velocity v and size d in the presence of an intrinsic local diffusivity D. Asymptotic solutions for effective diffusivity D*(P) in the large P limit, with P∼ vd/D, is shown to be of the form D*=cDP1/2 with c being a coefficient that is determined analytically. The constant c depends on the geometry of the convective cell and on an average of the flow speed along the separatrix. The asymptotic method of evaluation applies to both free boundary and rough boundary flow patterns and it is shown that the method can be extended to more complicated patterns such as the flows generated by rotating cylinders, as in the problem considered by Nadim, Cox, and Brenner [J. Fluid Mech. 164, 185 (1986)]. The diffusivity D* is readily calculated for small P, but the evaluation for arbitrary P requires numerical methods. Monte Carlo particle simulation codes are used to evaluate D* at arbitrary P, and thereby describe the transition for D* between the large and small P limits.
Closed universes with black holes but no event horizons as a solution to the black hole information problem

We show that it is possible for the information paradox in black hole evaporation to be resolved classically. Using standard junction conditions, we attach the general closed spherically symmetric dust metric to a space-time satisfying all standard energy conditions but with a single point future c-boundary. The resulting Omega Point space-time, which has NO event horizons, nevertheless has black hole type trapped surfaces and hence black holes. However, since there are no event horizons, information eventually escapes from the black holes. We show that a scalar quintessence field with an appropriate exponential potential near the final singularity would give rise to an Omega Point final singularity.
Seasonal and hemispheric variations of the total auroral precipitation energy flux from TIMED/GUVI

[1] The auroral hemispheric power (HP) has been calculated from the averaged energy flux derived from Far-ultraviolet emission observations made by the global ultraviolet imager (GUVI) instrument on board the Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) satellite during 2002–2007. This HP was used to study how variations in seasonal and hemispheric asymmetries changed with changing geomagnetic activity. Our results showed that there were persistent seasonal and hemispheric differences in quiet conditions. There were HP differences of about 1–3 GW between the summer and winter seasons in each hemisphere and also between the two hemispheres during each solstice period for low geomagnetic activity (Kp ≤ 3). The summer-winter asymmetry was 4%–35% when HP was low. These summer-winter differences became negligible when geomagnetic activity was moderate to active. Similarly, there were also HP differences of about 2 GW between local summers of the two hemispheres during geomagnetically quiet conditions (Kp < 3) but not during higher Kp conditions. The hemispheric asymmetries between the two summer solstices were about 10%–20% during quiet conditions, whereas there was no apparent hemispheric asymmetry between the two winter solstices under all Kp 1–5 conditions. Solar illumination effects were probably the primary cause of the seasonal and hemispheric variations of the auroral hemispheric power for these geomagnetically quiet conditions. During moderate and active conditions the conductivities were driven more by the production of ionization due to precipitation, so the precipitation was more symmetric.
A Virtual Space for Children to Meet and Practice Chinese

Second language acquisition after the students have learned their first language is a unique process. One major difference between learning a foreign language and one’s mother tongue is that second language learning is often facilitated with digital media, and in particular, through interacting with computers. This project is aimed at leveraging computer game technologies and Microsoft Kinect camera to create virtual learning environments suitable for children to practice their language and culture skills. We present a unique virtual environment that contextualizes the practice and engages the learners with narratives, encourages group work and leverages the power of embodied cognition in language learning. Our system has been deployed in an afterschool program for children from 6 to 8 years old. We report our evaluation results and reflections on the deployment process, followed by discussion and future work.
Analysis of thermohydrologic behavior for above-boiling and below-boiling thermal-operating modes for a repository at Yucca Mountain.

Abstract We report results from a multi-scale thermohydrologic modeling study for two alternative thermal-operating modes for the potential repository system recently analyzed by the Yucca Mountain Project. These include a Higher-Temperature Operating Mode (HTOM), which results in a localized boiling zone around each emplacement drift, and a Lower-Temperature Operating Mode (LTOM), which always maintains sub-boiling temperatures throughout the repository. The HTOM places all waste packages nearly end to end, making the lineal power density greater than in the LTOM. The lower lineal power density in the LTOM was achieved by placing some waste packages farther apart (which results in a larger repository footprint), and through an increased reliance on pre-closure ventilation to remove the waste-package-generated heat. We focus on temperature T and relative humidity RH at the waste-package and drift-wall surfaces, and on in-drift evaporation. In general, HTOM temperatures are greater than corresponding LTOM temperatures, exhibit similar spatial variability and have a stronger dependence on infiltration flux. The duration of RH reduction on waste packages is similar for the LTOM and HTOM. A major difference between the LTOM and HTOM is the lower waste-package temperature at any given value of waste-package RH for the LTOM. Waste-package temperatures in the LTOM, by design, remain below ∼85 °C; the absence of RH reduction arising from host-rock dryout causes waste-package RH to remain above about 40%. The HTOM waste packages experience higher temperatures and correspondingly lower RH conditions as a result of RH reduction arising from host-rock dryout. For most of the repository area, the HTOM delays the potential onset of gravity-driven seepage compared to the LTOM (as indicated by the duration of boiling at the drift wall). Boiling conditions in the HTOM also delays the onset of capillary-driven seepage into the granular invert, causing the HTOM to have less evaporation in the invert during the first 800–1500 years than the LTOM; subsequent evaporation rates are higher in the HTOM, due to the higher power density.
Zanamivir Conjugated to Poly- L -Glutamine is Much More Active Against Influenza Viruses in Mice and Ferrets Than the Drug Itself

Previously, polymer-attached zanamivir had been found to inhibit influenza A viruses in vitro far better than did small-molecule zanamivir (1) itself. The aim of this study was to identify in vitro—using the plaque reduction assay—a highly potent 1-polymer conjugate, and subsequently test its antiviral efficacy in vivo. By examining the structure-activity relationship of 1-polymer conjugates in the plaque assay, we have determined that the most potent inhibitor against several representative influenza virus strains has a neutral high-molecular-weight backbone and a short alkyl linker. We have examined this optimal polymeric inhibitor for efficacy and immunogenicity in the mouse and ferret models of infection. 1 attached to poly-L-glutamine is an effective therapeutic for established influenza infection in ferrets, reducing viral titers up to 30-fold for 6 days. There is also up to a 190-fold reduction in viral load when the drug is used as a combined prophylactic/therapeutic in mice. Additionally, we see no evidence that the drug conjugate stimulates an immune response in mice upon repeat administration. 1 attached to a neutral high-molecular-weight backbone through a short alkyl linker drastically reduced both in vitro and in vivo titers compared to those observed with 1 itself. Thus, further development of this polymeric zanamivir for the mitigation of influenza infection seems warranted.
Different cation arrangements in Au-In networks. Syntheses and structures of six intermetallic compounds in alkali-metal-Au-In systems.

Six robust intermetallic compounds with cations in three different tunnel-like structures have been synthesized in alkali-metal-Au-In systems via high-temperature solid-state methods and characterized by X-ray diffraction: AAu{sub 4}-In{sub 6} [A = K (I), Rb (II), F6m2, Z = 1], K{sub 1.76(6)}Au{sub 6}Ln{sub 4} (III,; 4/mcm, Z = 4), and A{sub x}Au{sub 2}In{sub 2} [x{approx} 0.7, A = K (IV), Rb (V), Cs (VI), P4{sub 2}/nmc, Z = 8]. The first type is constructed from a single cage unit: an alkali-metal-centered 21-vertex polyhedron A@AugIn12 with 6-9-6 arrangement of planar rings. The others contain uniaxial arrays of tunnels built of differently puckered eight- and four-member Au/In rings. The largely different cation distributions depend on the tunnel constitutions and cation sizes. Tight-binding electronic structure calculations by linear muffin-tin-orbital (LMTO) methods were performed for I and idealized III in order to help understand their chemical bonding. These also reveal large differences in relativistic effects for Au d orbitals, as well as for different Au sites in each structure.