cssi/SciSciGPT-SciSciNet huggingface dataset:
Planets Formed in Habitable Zones of M Dwarf Stars Probably Are Deficient in Volatiles

Dynamical considerations, presented herein via analytic scalings and numerical experiments, imply that Earth-mass planets accreting in regions that become habitable zones of M dwarf stars form within several million years. Temperatures in these regions during planetary accretion are higher than those encountered by the material that formed the Earth. Collision velocities during and after the prime accretionary epoch are larger than for Earth. These factors suggest that planets orbiting low-mass main-sequence stars are likely to either be too distant (and thus too cold) for carbon/water based life on their surfaces or have abundances of the required volatiles that are substantially less than on Earth.
Sterile Plus Active Neutrinos and Neutrino Oscillations

Using a 3 + 1 neutrino model with one sterile and the three standard active neutrinos with a 4 × 4 unitary transformation matrix, U, relating flavor to mass neutrino states, the probability of ν μ to ν e transition is estimated using sterile-active neutrino masses determined by MiniBooNE and other experiments and sterile-active neutrino angles in the 4 × 4 U matrix.
USER PROFILING IN THE CHRONOBOT/VIRTUAL CLASSROOM SYSTEM

The Chronobot/Virtual Classroom (CVC) system is a novel time knowledge exchange platform where any pair of users can exchange their time and knowledge. User profile that contains user attributes, preferences, and learning patterns serves as a primary basis to identify exchange partners and determine exchange rates. In this paper, we described the methodology to acquire knowledge about users i.e. user profile from their activities. The association between user profile and user behaviors (e.g. online reading, chatting and time/knowledge exchanging) is identified by several feedback indicators extracted from browsing history, chatting session and exchange transaction. A linear learning model is constructed to fuse multiple feedback indicators to infer user preference. The methods utilizing user profile to identify the exchange partners and determine the exchange rate are also described in detail.
Trailing-Edge Flows at High Reynolds Number

An investigation of trailing-edge flows at high Reynolds number and subsonic Mach numbers is presented. Symmetric and asymmetric trailing-edge flows are studied, each flow having pressure gradient regions upstream of the trailing edge similar to an airfoil. Measurements include model surface pressures, mean velocity, turbulent shear stress, and turbulent kinetic energy profiles in the trailing-edge and near-wake regions. Comparisons of the symmetric data with numerical solutions of boundary layer as well as Navier-Stokes equations employing two different turbulence models show increasing effects on viscous interactions as the Mach number increases. Both turbulence models yielded solutions of the mean flow of comparable quality. The experimental results of the asymmetric case are discussed.
Air pollution and the housing market: A neural network approach

Using the neural network method, this research explores the impact of total suspended particulate (TSP) and sulfur dioxide (SO2), two major air pollutants, and of air pollution controls on the median real price of housing in Jacksonville, Florida. The results of this case study confirm the adverse effect of air pollution on the price of housing. The simulation of the model further suggests that pollution control measures improve property values. The findings imply that, in addition to other measures influencing the price of housing, property owners and buyers take air pollution and pollution controls into account.
Almost global existence for some semilinear wave equations

We prove almost global existence for semilinear wave equations outside of nontrapping obstacles. We use the vector field method, but only use the generators of translations and Euclidean rotations. Our method exploits 1/r decay of wave equations, as opposed to the much harder to prove 1/t decay.
Chandra X-Ray Imaging Spectroscopy of the Young Supernova Remnant Kesteven 75

We present a spatially resolved spectroscopic analysis of the young Galactic supernova remnant Kes 75 (SNR G29.7-0.3) using the Chandra X-Ray Observatory. Kes 75 is one of an increasing number of examples of a shell-type remnant with a central pulsar powering an extended radio/X-ray core. We are able to pinpoint the location of the recently discovered pulsar, PSR J1846-0258, and confirm that X-rays from the remnant's core component are consistent with nonthermal power-law emission from both the pulsar and its surrounding wind nebula. We find that the spectrum of the pulsar is significantly harder than that of the wind nebula. Fainter diffuse emission is detected from throughout the volume delineated by the radio shell with a surface brightness distribution strikingly similar to the radio emission. The presence of strong lines attributable to ionized Mg, Si, and S indicates that at least some of this emission is thermal in nature. However, when we characterize the emission using a model of an underionized plasma with nonsolar elemental abundances, we find that we require an additional diffuse high-energy component. We show that a significant fraction of this emission is an X-ray scattering halo from the pulsar and its wind nebula, although a nonthermal contribution from electrons accelerated in the shock cannot be excluded.
Bright White Light Emission from Ultrasmall Cadmium Selenide Nanocrystals

A simple treatment method using formic acid has been found to increase the fluorescence quantum yield of ultrasmall white light-emitting CdSe nanocrystals from 8% to 45%. Brighter white-light emission occurs with other carboxylic acids as well, and the magnitude of the quantum yield enhancement is shown to be dependent on the alkyl chain length. Additionally, the nanocrystal luminescence remains enhanced relative to the untreated nanocrystals over several days. This brightened emission opens the possibility for even further quantum yield improvement and potential for use of these white-light nanocrystals in solid-state lighting applications.
Changing Agricultural Markets: Industrialization and Vertical Coordination in the Dry Edible Bean Industry

The agricultural sector is undergoing a transformation that is altering marketing relationships to better serve customer needs. These changes are drawing consumers, processors, and farmers into closer marketing relationships, improving the flow of information up the supply chain, and enabling firms to better meet customer demand. This paper uses case studies to analyze this process as it is occurring in the dry edible bean industry. A major finding is that contracts are not necessarily used in these new marketing relationships. Other factors—such as quality monitoring, certification procedures, and reputation—were also found to be highly important.
BOUNDARY EFFECTS IN (2 + 1)-DIMENSIONAL MAXWELL-CHERN-SIMONS THEORY

The effects of the sample's boundaries in the magnetic response of the charged anyon fluid at finite temperature are investigated. For the case of an infinite-strip sample it is shown that the Meissner effect takes place at temperatures lower than the fermion energy gap ωc. The temperature dependence of the corresponding effective penetration depth is determined. At temperatures much larger than the scale ωc, a different phase is found, in which the external magnetic field penetrates the fluid.
Strong coupling between excitons in J aggregates and waveguide modes in thin polymer films

We observe waveguide exciton-polaritons with large room temperature Rabi splittings of 190 meV and 125 meV for TE and TM modes respectively. The experimental results are in good agreement with numerical simulations.
Variations in cloud condensation nuclei at palmer station antarctica during february 1994

Abstract Cloud Condensation Nuclei (CCN) activity spectra and meteorological data were measured between February 12 and February 26, 1994 at Palmer Station, Antarctica. The CCN concentrations (at ≈ 1.3% supersaturation) ranged from −3 with an average of 20 cm −3 . The lower CCN concentrations were measured during fog, precipitation, or fogless periods following widespread precipitation. The higher CCN concentrations were observed in the vicinity of virga and evaporating low level clouds, as well as during pollution episodes. The CCN spectra were typical of a marine location. The meteorological and CCN spectral data indicate a significant change in the total CCN concentration measured in association with the sampling near the fog-free boundary of different air-masses or air-parcels, including those from evaporating clouds.
Thermal degradation studies of several Pyrrone films

Thermal degradation of polyimidazopyrrolone /pyrrone/ films in air and vacuum, using thermogravimetric analysis
Enantioselective Synthesis of Axially Chiral Biaryls by the Pd-Catalyzed Suzuki-Miyaura Reaction: Substrate Scope and Quantum Mechanical Investigations

We report efficient syntheses of axially chiral biaryl amides in yields ranging from 80−92%, and with enantioselectivity in the range 88−94% ee employing an asymmetric Suzuki−Miyaura process with Pd(OAc)2 and KenPhos as ligand. These studies demonstrate that electron-rich and electron-deficient o-halobenzamides can be efficiently coupled with 2-methyl-1-naphthylboronic acid and 2-ethoxy-1-naphthylboronic acid. The yields and selectivities of the reactions are independent of the nature of halogen substituent on the benzamide coupling partner. Our investigations demonstrate that axially chiral heterocyclic and biphenyl compounds can also be synthesized with this methodology. We also report computational studies used to determine the origin of stereoselectivity during the selectivity-determining reductive elimination step of the related coupling of tolyl boronic acid with naphthylphosphonate bromide that was reported in a previous publication (J. Am. Chem. Soc. 2000, 122, 12051−12052). These studies indicate...
Discovery of error-tolerant biclusters from noisy gene expression data.

An important analysis performed on microarray gene-expression data is to discover biclusters, which denote groups of genes that are coherently expressed for a subset of conditions. Various biclustering algorithms have been proposed to find different types of biclusters from these real-valued gene-expression data sets. However, these algorithms suffer from several limitations such as inability to explicitly handle errors/noise in the data; difficulty in discovering small bicliusters due to their top-down approach; inability of some of the approaches to find overlapping biclusters, which is crucial as many genes participate in multiple biological processes. Association pattern mining also produce biclusters as their result and can naturally address some of these limitations. However, traditional association mining only finds exact biclusters, which limits its applicability in real-life data sets where the biclusters may be fragmented due to random noise/errors. Moreover, as they only work with binary or boolean attributes, their application on gene-expression data require transforming real-valued attributes to binary attributes, which often results in loss of information. Many past approaches have tried to address the issue of noise and handling real-valued attributes independently but there is no systematic approach that addresses both of these issues together. In this paper, we first propose a novel error-tolerant biclustering model, ‘ET-bicluster’, and then propose a bottom-up heuristic-based mining algorithm to sequentially discover error-tolerant biclusters directly from real-valued gene-expression data. The efficacy of our proposed approach is illustrated by comparing it with a recent approach RAP in the context of two biological problems: discovery of functional modules and discovery of biomarkers. For the first problem, two real-valued S.Cerevisiae microarray gene-expression data sets are used to demonstrate that the biclusters obtained from ET-bicluster approach not only recover larger set of genes as compared to those obtained from RAP approach but also have higher functional coherence as evaluated using the GO-based functional enrichment analysis. The statistical significance of the discovered error-tolerant biclusters as estimated by using two randomization tests, reveal that they are indeed biologically meaningful and statistically significant. For the second problem of biomarker discovery, we used four real-valued Breast Cancer microarray gene-expression data sets and evaluate the biomarkers obtained using MSigDB gene sets. The results obtained for both the problems: functional module discovery and biomarkers discovery, clearly signifies the usefulness of the proposed ET-bicluster approach and illustrate the importance of explicitly incorporating noise/errors in discovering coherent groups of genes from gene-expression data.
A new method for the conversion of enol phenyl thioethers to ketones

Abstract Exposure of enol thioethers at ambient temperature to in situ -generated hydrogen iodide in acetonitrile containing mercuric chloride gives rise to ketones in yields ranging from 74 – 87%.
On the Behavior of Minimal Free Resolutions of Trivariate Generic Monomial Ideals

We will explore some properties of minimal graded free resolutions of R/I, where R is a trivariate polynomial ring over a field and I is a monomial ideal. Our focus will be to consider a specific form of the resolutions when I is primary to the homogeneous maximal ideal. We will identify certain characteristics of the last matrix of these resolutions, and observe differences in the resolutions for generic ideals in comparison to nongeneric ideals. Finally, we learn how to identify whether I is generic by knowing the structure of the last matrix in the minimal free resolution of R/I.
Fish effects on ocean current observations in the Cariaco Basin

[1] Multiple years of moored current meter observations from the Cariaco Basin show low-frequency variations along with near-inertial waves and further imply the persistent diurnal movement of fish species known to populate the basin. In agreement with short-term observations from 1979, the more recent observations with acoustic Doppler current profilers provide evidence of the multidecadal presence and behavior of these species. An unwanted corollary, however, is a bias in both the vertical and horizontal components of velocity due to the fish movements. Removal of this fish bias results in large data loss (approximately 72%); however, an interpolated, non-biased data set is developed with depth-averaged horizontal velocities comparable to the observations, demonstrating successful elimination of the bias. Further comparisons show that the interpolated data result in minimal variance density loss at low frequencies and a reduction of variance density at high frequencies such that the interpolated data in the internal wave range more closely fit the Garrett-Munk spectrum. The net result is a data set appropriate for further analysis. A mean downward velocity of 0.18 cm s−1 is a reflection of a biogenic particle flux and some residual fish contamination. The mean settling speed of particles in the Cariaco Basin is calculated, via Stokes law, to be smaller than 0.04 cm s−1. Velocity observations from acoustic current meters at depths greater than 400 m are impacted by the water clarity; therefore alternate methods should be used to make velocity measurements at depth.
Tuning nonlinear susceptibility in strained AlGaAs/InGaAs quantum cascade lasers

Abstract This paper explores enhancement of nonlinear susceptibility in strained quantum cascade lasers (QCLs) that lead to unique intracavity characteristics that include frequency mixing producing both fundamental and higher order modes that propagate freely within a GaAs matrix. Doing so provides a QCL cavity design with emission near the 3.5 μm range, a region suitable for applications within the 3–5 μm atmospheric transmission window. In this study, a self-consistent Schrodinger–Poisson solver was employed to analyze the effects of strain within an AlGaAs/InGaAs active region between AlGaAs/GaAs injectors on a [1 1 1] GaAs matrix for the purpose of enhancing nonlinear susceptibility. Strain relief available through the use of [1 1 1] GaAs allows increased indium composition in the active region and results in observation of second-harmonics below the 5 μm range with tunable optical dipole moments and oscillator strengths. Results demonstrate the feasibility of strained AlGaAs/InGaAs devices on GaAs for producing higher order harmonics that lay below the 4 μm spectral limit.
Continuum coupled-cluster expansion

We review the basics of the coupled-cluster expansion formalism for numerical solutions of the many-body problem, and we outline the principles of an approach directed towards an adequate inclusion of continuum effects in the associated single-energy spectrum. We illustrate our findings by considering the simple case of a single-particle quantum mechanics problem.
Synthesis and Characterization of Nanometer-Size Fe3O4 and γ-Fe2O3 Particles

Synthesis of suspensions of nanosize particles of Fe3O4 was carried out in bulk aqueous solutions without the presence of surfactants. The Fe3O4 nanoparticles were oxidized to γ-Fe2O3 by direct aeration of the suspension at 100 °C. The shape and size distribution and crystallinity of the Fe3O4 nanoparticles were assessed by transmission electron microscopy and selected area electron diffraction. Very uniform and stable colloidal suspensions of the Fe3O4 nanoparticles in water could be synthesized. Oxidation of the colloidal system leads to γ-Fe2O3 nanoparticles of much larger size than Fe3O4.
No chiral truncation of quantum log gravity

At the classical level, chiral gravity may be constructed as a consistent truncation of a larger theory called log gravity by requiring that left-moving charges vanish. In turn, log gravity is the limit of topologically massive gravity (TMG) at a special value of the coupling (the chiral point). We study the situation at the level of linearized quantum fields, focussing on a unitary quantization. While the TMG Hilbert space is continuous at the chiral point, the left-moving Virasoro generators become ill-defined and cannot be used to define a chiral truncation. In a sense, the left-moving asymptotic symmetries are spontaneously broken at the chiral point. In contrast, in a non-unitary quantization of TMG, both the Hilbert space and charges are continuous at the chiral point and define a unitary theory of chiral gravity at the linearized level.
Subcanonical points on algebraic curves

A point of an algebraic curve of genus g is subcanonical if some regular differential vanishes only at that point, with multiplicity 2g-2. Subcanonical points are Weierstrass points, and we compute the associated gap sequence at a general point of each component of the moduli space of curves with marked subcanonical point. We also construct subcanonical points with other gap sequences as ramification points of certain cyclic covers.
“Soft” Anharmonic Vortex Glass in Ferromagnetic Superconductors

Ferromagnetic order in superconductors can induce a spontaneous vortex (SV) state. For external field H=0 , rotational symmetry guarantees a vanishing tilt modulus of the SV solid, leading to drastically different behavior than that of a conventional, external-field-induced vortex solid. We show that quenched disorder and anharmoinc effects lead to elastic moduli that are wave-vector dependent out to arbitrarily long length scales, and non-Hookean elasticity. The latter implies that for weak external fields H , the magnetic induction scales universally like B(H){approx}B(0)+cH{sup {alpha}} , with {alpha}{approx}0.72 . For weak disorder, we predict the SV solid is a topologically ordered glass, in the ''columnar elastic glass'' universality class.
Automated algorithm for differentiation of human breast tissue using low coherence interferometry for fine needle aspiration biopsy guidance

Fine needle aspiration biopsy FNAB is a rapid and cost-effective method for obtaining a first-line diagno- sis of a palpable mass of the breast. However, because it can be difficult to manually discriminate between adipose tissue and the fibroglandular tissue more likely to harbor disease, this technique is plagued by a high number of nondiagnostic tissue draws. We have developed a por- table, low coherence interferometry LCI instrument for FNAB guidance to combat this problem. The device con- tains an optical fiber probe inserted within the bore of the fine gauge needle and is capable of obtaining tissue struc- tural information with a spatial resolution of 10 m over a depth of approximately 1.0 mm. For such a device to be effective clinically, algorithms that use the LCI data must be developed for classifying different tissue types. We present an automated algorithm for differentiating adipose tissue from fibroglandular human breast tissue based on three parameters computed from the LCI signal slope, standard deviation, spatial frequency content. A total of 260 breast tissue samples from 58 patients were collected from excised surgical specimens. A training set N=72 was used to extract parameters for each tissue type and the parameters were fit to a multivariate normal density. The model was applied to a validation set N=86 using like- lihood ratios to classify groups. The overall accuracy of the model was 91.9% 84.0 to 96.7 with 98.1% 89.7 to 99.9 sensitivity and 82.4% 65.5 to 93.2 specificity where the numbers in parentheses represent the 95% con- fidence intervals. These results suggest that LCI can be used to determine tissue type and guide FNAB of the breast. © 2008 Society of Photo-Optical Instrumentation Engineers.
Implementation of Surface Detector Option in Scale SAS4 Shielding Module

The Shielding Analysis Sequence No. 4 (SAS4) in the Standardized Cask Analysis and Licensing Evaluation System (SCALE) is designed to aid the novice user in the preparation of detailed three-dimensional models and radiation protection studies of transportation or storage packages containing spent fuel from a nuclear reactor facility. The underlying methodology in these analyses is the Monte Carlo particle-tracking approach as incorporated into the MORSE-SGC computer code. The use of these basic procedures is enhanced via the automatic generation of the biasing parameters in the SAS4 sequence, which dramatically increases the calculational efficiency of most standard shielding problems. Until recently the primary mechanism for dose estimates in SAS4 was the use of point detectors, which were effective for single-dose locations, but inefficient for quantification of dose-rate profiles. This paper describes the implementation of a new surface detector option for SAS4 with automatic discretization of the dete...
Self-duality, Ramond-Ramond fields, and K-theory

Just as D-brane charge of type-IIA and type-IIB superstrings is classified, respectively, by K-1(X) and K(X), Ramond-Ramond fields in these theories are classified, respectively, by K(X) and K-1(X). By analyzing a recent proposal for how to interpret quantum self-duality of RR fields, we show that the Dirac quantization formula for the RR p-forms, when properly formulated, receives corrections that reflect curvature, lower brane charges, and an anomaly of D-brane world-volume fermions. The K-theory framework is important here, because the term involving the fermion anomaly cannot be naturally expressed in terms of cohomology and differential forms.
Potential climatic impacts and reliability of very large-scale wind farms

Abstract. Meeting future world energy needs while addressing climate change requires large-scale deployment of low or zero greenhouse gas (GHG) emission technologies such as wind energy. The widespread availability of wind power has fueled substantial interest in this renewable energy source as one of the needed technologies. For very large-scale utilization of this resource, there are however potential environmental impacts, and also problems arising from its inherent intermittency, in addition to the present need to lower unit costs. To explore some of these issues, we use a three-dimensional climate model to simulate the potential climate effects associated with installation of wind-powered generators over vast areas of land or coastal ocean. Using wind turbines to meet 10% or more of global energy demand in 2100, could cause surface warming exceeding 1 °C over land installations. In contrast, surface cooling exceeding 1 °C is computed over ocean installations, but the validity of simulating the impacts of wind turbines by simply increasing the ocean surface drag needs further study. Significant warming or cooling remote from both the land and ocean installations, and alterations of the global distributions of rainfall and clouds also occur. These results are influenced by the competing effects of increases in roughness and decreases in wind speed on near-surface turbulent heat fluxes, the differing nature of land and ocean surface friction, and the dimensions of the installations parallel and perpendicular to the prevailing winds. These results are also dependent on the accuracy of the model used, and the realism of the methods applied to simulate wind turbines. Additional theory and new field observations will be required for their ultimate validation. Intermittency of wind power on daily, monthly and longer time scales as computed in these simulations and inferred from meteorological observations, poses a demand for one or more options to ensure reliability, including backup generation capacity, very long distance power transmission lines, and onsite energy storage, each with specific economic and/or technological challenges.
Recent developments in oxide ion conductors: Aurivillius phases

Recent advances in the study of Aurivillius phases (Bi2An-1BnO3n+3, n = 1−5) as oxide ion conductors are presented. The structures of modified Aurivillius phases containing extrinsic oxygen vacancies as well as Aurivillius phases containing intrinsic oxygen vacancies are surveyed. A detailed discussion of the conductivity behavior of these Aurivillius phases is given.
Komar integrals in higher (and lower) derivative gravity

The Komar integral relation of Einstein gravity is generalized to Lovelock theories of gravity. This includes, in particular, a new boundary integral for the Komar mass in Einstein gravity with a non-zero cosmological constant, which has a finite result for asymptotically AdS black holes, without the need for an infinite background subtraction. Explicit computations of the Komar mass are given for black holes in pure Lovelock gravities of all orders and in general Gauss–Bonnet theories.
Thickenings and conformal gravity

A twistor correspondence is given for complex conformal space-times with vanishing Bach and Eastwood-Dighton tensors; when the Weyl curvature is algebraically general, these equations are precisely the conformal version of Einstein's vacuum equations with cosmological constant. This gives a fully curved version of the linearized correspondence of Baston and Mason [B-M].
A quasispecies on a moving oasis

A population evolving in an inhomogeneous environment will adapt differently to different areas. We study the conditions under which such a population can maintain adaptations to a particular region when that region is not stationary, but can move. In particular, we consider a haploid population living near a moving favorable patch ("oasis") in the middle of a large "desert." At one genetic locus, individuals may have one of a few gene sequences that convey an advantage while in the oasis at the cost of a disadvantage in the desert. The distribution of genetic states in the population, possibly localized in genome space around the oasis-adapted genotypes, is known as a quasispecies. We find that the ratio of oasis-adapted individuals to desert-adapted ones exhibits sharp transitions at particular oasis velocities. We calculate an extinction velocity, and a switching velocity above which the dominance switches from the oasis-adapted genotype to the desert-adapted one. This switching velocity is analogous to the quasispecies mutational error threshold. Above this velocity, the population cannot maintain adaptations to the properties of the oasis.
Polycrystalline thin-film technologies: Status and prospects

Abstract The recent progress towards high-efficiency thin-film polycrystalline solar cells is examined in this paper together with a brief history of their development. We focus on the three materials of contemporary interest for such devices: polycrystalline Si, CuInSe 2 and its alloys, and CdTe. Although there has often been an implicit assumption that thin-film devices required a compromise of lower efficiency than their single, or bulk polycrystalline competitors, we now see for the first time that polycrystalline thin-film solar cells can rival these devices. In dispelling this myth, we examine the elements that have contributed to the progress in each area.
Application of a high-precision Universal Measuring Machine in standards laboratory measurements

A computer-controlled high-precision Universal Measuring Machine (UMM) of advanced design is being applied to the calibration of high-precision artifacts in one- and two-dimensional space, aided by checks against master length reference standards. These artifacts, principally step-gages and roundness standards, require ratio-type techniques similar to those employed in calibration of electrical ratio devices. The application is yielding significant time savings and accuracy enhancement. Analytical power of the machine's computer system simplifies data collection, improves computation of results, and permits deterministic analysis where best judgment has been the practice.
A unified model of acoustic and lattice waves in a one-dimensional strongly coupled dusty plasma

An exact dispersion relation is obtained for linear dust-compressional waves in a one-dimensional plasma crystal consisting of cold dust particles located at lattice points uniformly spaced in equilibrium. This general dispersion relation reduces in asymptotic limits to the dust-acoustic and dust-lattice wave dispersion relations. Implications for experiments are discussed.
Synthesis and characterization of transition-metal Zintl phases: Cs24Nb2In12As18 and Cs13Nb2In6As10 with isolated complex anions.

The title compounds were prepared by direct reaction of the corresponding elements at high temperature. Their structures were determined by single-crystal X-ray diffraction (Cs 2 4 Nb 2 In 1 2 As 1 8 , triclinic, P1, Z = 1, a= 9.519(4), b = 9.540(5), and c = 25.16(1) A, α = 86.87(4), β = 87.20(4), and y = 63.81(4)°; Cs 1 3 Nb 2 In 6 As 1 0 , triclinic, P1, Z = 1, a = 9.5564(5), b = 9.6288(5), and c = 13.9071(7) A, α = 83.7911(8), β = 80.2973(8), and y = 64.9796(8)°). Cs 2 4 Nb 2 In 1 2 As 1 8 and Cs 1 3 Nb 2 In 6 As 1 0 contain isolated anions of [Nb 2 In 1 2 As 1 8 ] 2 4 - and [Nb 2 In 6 As 1 0 ] 1 3 - , respectively. Each anion includes two cubane-like units made of one niobium, three indium, and four arsenic corners where a fifth arsenic atom completes the tetrahedral coordination at niobium, [(NbAs)In 3 As 4 ]. In Cs 1 3 Nb 2 -In 6 As 1 0 these two units are connected via a direct In-In bond between two indium vertexes of the cubanes. In Cs 2 4 Nb 2 In 1 2 As 1 8 , on the other hand, the same two units are linked by a dimer made of semicubanes of [In 3 As 4 ], i.e., a cubane with one missing vertex. Magnetic measurements show that Cs 2 4 Nb 2 In 1 2 As 1 8 is diamagnetic, i.e., a d° transition-metal Zintl phase, while Cs 1 3 Nb 2 In 6 As 1 0 exhibits a Curie-Weiss behavior that corresponds to one unpaired electron.
Ecdysozoa: The Relationship between Cycloneuralia and Panarthropoda

Abstract The hypothesis that molting protostomes such as nematodes and arthropods form a monophyletic group known as Ecdysozoa is directly opposed to Articulata, in which some segmented protostomes such as annelids and arthropods form a monophyletic taxon. Ultrastructural and cladistic studies have led to the widely accepted hypothesis that nematodes belong among the protostomes. While early molecular studies suggested that nematodes were basal triploblasts, more recent molecular evidence suggests that this was an artifact of ‘long branch attraction’ and 18S rRNA gene, total evidence and hox gene studies all support the placement of nematodes within Ecdysozoa. The branching pattern within Ecdysozoa has been difficult to elucidate, but it now appears that priapulids and kinorhynchs form the earliest branching clade, followed by nematodes + nematomorphs, and finally the panarthropods. This suggests that Cycloneuralia is paraphyletic and that arthropods are the most derived of the ecdysozoans.
Large-N analysis of the Higgs mass triviality bound

Abstract We calculate the triviality bound on the Higgs mass in scalar field theory models whose global symmetry group SU(2)L × SU(2)custodial ≈ O(4) has been replaced by O(N) and N has been taken to infinity. Limits on observable cutoff effects at 4% in several regularized models with tunable couplings in the bare action yield triviality bounds displaying a large degree of universality. Extrapolating from N = ∞ to N = 4 we conservatively estimate that a Higgs particle with mass up to 0.750 TeV and width up to 0.290 TeV is realizable without large cutoff effects, indicating that strong scalar self-interactions in the standard model are not ruled out.
Destabilizing divergences in supergravity theories at two loops

Abstract We examine the stability of the mass hierarchy in hidden-sector supergravity theories. We show that a quadratically divergent tadpole can appear at two loops, even in minimal supergravity theories, provided the theory has a gauge- and global-symmetry singlet with renormalizable couplings to the visible fields. This tadpole can destabilize the hierarchy. We also find a quadratically divergent two-loop contribution to the field-dependent vacuum energy. This result casts doubt on the efficacy of the “LHC mechanism” for controlling quadratic divergences. We carry out the two-loop calculation in a manifestly supersymmetric formalism, and explain how to apply the formalism in the presence of supersymmetry breaking to derive radiative corrections to the supersymmetric and soft supersymmetry-breaking operators. Our approach greatly simplifies the calculation and guarantees consistency of our results with the underlying supergravity framework.
BF3·OEt2-Promoted Concise Synthesis of Difluoroboron-Derivatized Curcumins from Aldehydes and 2,4-Pentanedione.

Abstract A concise and one-pot cascade method has been developed to achieve the synthesis of difluoroboron-derivatized curcumins (BF2C). Treatment of 2,4-pentanedione with BF3·OEt2, followed by condensation with aldehydes in the presence of tributyl borate and butylamine at 65 °C in toluene furnished the corresponding symmetric (s-BF2C) and unsymmetric difluoroboron-derivatized curcumins (us-BF2C) in good (60–99%) and moderate yields (23–42%) within 6–12 h, respectively.
Hamiltonian lattice gauge theory: wavefunctions on large lattices

We discuss an algorithm for the approximate solution of Schrodinger's equation for lattice gauge theory, using lattice SU(3) as an example. A basis is generated by repeatedly applying an effective Hamiltonian to a “starting state.” The resulting basis has a cluster decomposition and long-range correlations. One such basis has about 104 states on a 10 × 10 × 10 lattice. The Hamiltonian matrix on the basis is sparse, and the elements can be calculated rapidly. The lowest eigenstates of the system are rapidly calculable.
Michael Addition of Allenoates to Electron-Deficient Olefins: Facile Synthesis of 2-Alkynyl-Substituted Glutaric Acid Derivatives

A Michael addition of allenoates to electron-deficient olefins was mediated efficiently by a catalytic amount of commercial tetra-n-butylammonium fluoride (TBAF) under mild conditions. And 2-alkynyl substituted glutaric acid derivatives, which may be potential building blocks in organic synthesis, were obtained in good to excellent yields from these reactions. The mechanism for the Michael addition reaction may involve the formation of an alkynylenolate intermediate.
Total Synthesis of (−)‐Tetrazomine and Determination of Its Stereochemistry

A new method for the formation of the allylic amine precursor to an azomethine ylide 1 has been developed and exploited in an efficient 1,3-dipolar cycloaddition to afford the key tetracyclic intermediate used in the synthesis of (-)-tetrazomine (2). Bn=benzyl.
Dynamic critical behavio(u)r of a cluster algorithm for the Ashkin-Teller model

We study the dynamic critical behavior of a Swendsen-Wang-type algorithm for the Ashkin-Teller model. We find that the Li-Sokal bound on the autocorrelation time (τint,ɛ ≥ const × CH) holds along the self-dual curve of the symmetric Ashkin-Teller model, but this bound is apparently not sharp. The ratio τint, ɛ /CH appears to tend to infinity either as a logarithm or as a small power (0.05 ≲ p ≲ 0.12).
Charmonium disintegration by field ionization

Abstract Charmonium bound states immersed in a coherent chromo-electric field are easily ripped apart for field strengths comparable to the QCD string tension. Estimates based on flux tube models suggest that field strengths of such magnitude may be achieved in heavy-ion collisions at ultrarelativistic energies. Our results suggest that charmonium suppression would not discriminate between a coherent and a thermalized post collision state in relativistic heavy-ion collisions.
Laurentia, Australia, and Antarctica as a Late Proterozoic supercontinent: Constraints from isotopic mapping

The reconstruction of Laurentia, Australia, and Antarctica into a Proterozoic supercontinent is evaluated by analyzing the fit of Precambrian provinces defined by isotopic and geochronologic mapping. The analysis is complicated by allochthonous segments of the Antarctic and eastern Australian margins. Removal of the allochthonous provinces produces a closer fit of the continents; there is a match of Early Proterozoic basement between southwestern Laurentia and the only exposure of craton known from the paleo-Pacific margin of Antarctica. In addition, western Laurentia is brought closer to the Australian Gawler block, consistent with provenance interpretations of the Belt Supergroup. Removal of the allochthonous provinces by right-lateral translation relative to the Antarctic craton margin places them in a pre-750 Ma position where they could be southwestward extensions of the Yavapai-Mazatzal and Grenville provinces of southern Laurentia. This modified reconstruction leads to a prediction of extensive Archean basement in Antarctica between the South Pole and Victoria Land, a prediction partly borne out by Archean rocks in the Miller Range of the Transantarctic Mountains; it also predicts the presence of 1.4Ga rapakivi granites in the Transantarctic Mountains basement. This configuration implies assembly of the Australia-Antarctica Gondwana margin by terrane accretion following, or accompanied by, left-lateral translation. This is compatible with a tectonic regime of clockwise rotation of Laurentia relative to Australia and Antarctica after rifting. Thus, the proposed supercontinent, with some modifications, has potential for explaining several aspects of the pattern of Precambrian provinces in the three continents.
Twin-chamber Knudsen effusion cell source mass spectrometry: vaporization of palladium

Abstract A novel vapor source for high temperature mass spectrometry has been developed recently in our laboratory. With this twin-chamber Knudsen cell source the vaporization of a sample can be compared simultaneously with a vapor pressure reference material ( e.g. gold). This eliminates many errors due to the usual calibration with silver or gold. The vapor pressure of pure palladium is redetermined using this vapor source with gold as the reference substance from 1450 K to the melting point of palladium. The enthalpy of sublimation, ΔH v o ( Pd , 298 K ) = 90.3 ± 0.20 kcal mol −1 , obtained from the third law treatment of the data is in excellent agreement with the corresponding enthalpy value of 90.0 ± 0.5 kcal mol −1 recommended by Hultgren et al. , and also with the value of 89.8 ± 0.8 kcal mol −1 deduced from the second law method. The temperature dependence of the vapor pressure of palladium is calculated to be lg( p atm ) = (6.12 ± 0.02) − (19230 ± 200) T This value of equilibrium pressure is probably the best value for this parameter.
Synthesis of new penicillin derivatives as drug-like molecules for biological screening

Abstract Chemical modification of penicillin β-lactam ring was made. Six thiazolidine amides were produced through N4-C7 β-lactam ring opening of penicillin V methyl ester with various aliphatic, aromatic, and heterocyclic primary amines. Five 8-hydroxypenillic acid derivatives with side chains of methyl, propyl, benzyl, and diethylaminoethyl groups were yielded via β-lactam ring rearrangement from 6-aminopenicillanic acid (6-APA). Parallel synthetic methods were used for the alkylation of 8-hydroxypenillic acid and β-lactam ring opening of penicillin V methyl ester. The biological activities of the compounds were evaluated.
Search for a liquid-liquid critical point in models of silica

Previous research has indicated the possible existence of a liquid-liquid critical point (LLCP) in models of silica at high pressure. To clarify this interesting question we run extended molecular dynamics simulations of two different silica models (WAC and BKS) and perform a detailed analysis of the liquid at temperatures much lower than those previously simulated. We find no LLCP in either model within the accessible temperature range, although it is closely approached in the case of the WAC potential near 4000 K and 5 GPa. Comparing our results with those obtained for other tetrahedral liquids, and relating the average Si–O–Si bond angle and liquid density at the model glass temperature to those of the ice-like β-cristobalite structure, we conclude that the absence of a critical point can be attributed to insufficient “stiffness” in the bond angle. We hypothesize that a modification of the potential to mildly favor larger average bond angles will generate a LLCP in a temperature range that is accessible to simulation. The tendency to crystallize in these models is extremely weak in the pressure range studied, although this tendency will undoubtedly increase with increasing stiffness.
A Log-Linear Graphical Model for inferring genetic networks from high-throughput sequencing data

Gaussian graphical models are often used to infer gene networks based on microarray expression data. Many scientists, however, have begun using high-throughput sequencing technologies to measure gene expression. As the resulting high-dimensional count data consists of counts of sequencing reads for each gene, Gaussian graphical models are not optimal for modeling gene networks based on this discrete data. We develop a novel method for estimating high-dimensional Poisson graphical models, the Log-Linear Graphical Model, allowing us to infer networks based on high-throughput sequencing data. Our model assumes a pair-wise Markov property: conditional on all other variables, each variable is Poisson. We estimate our model locally via neighborhood selection by fitting 1-norm penalized log-linear models. Additionally, we develop a fast parallel algorithm permitting us to fit our graphical model to high-dimensional genomic data sets. We illustrate the effectiveness of our methods for recovering network structure from count data through simulations and a case study on breast cancer microRNA networks.
Synthesis of homoallylic amines by hydrozirconation-imine addition of allenes.

Hydrozirconation of allenes followed by in situ transmetalation to dialkylzinc leads to the formation of an allylic zinc species that, upon addition of aldimines to the reaction mixture, provides homoallylic amines in 64−85% yield.
Neutrino physics: Where do we stand, and where are we going? — The theoretical-phenomenological perspective

The discoveries and open questions in neutrino physics, as reported at Neutrino 2002 and more recently, are reviewed from a theoretical perspective.
Environmental view and color for a simulated telemarketing task

In two experiments, task type or a break, environmental color, and environmental view were manipulated to determine their effects on mood, satisfaction, motivation, and performance. Mood, specifically negative mood, and performance satisfaction tended to be affected by what one did, not by the environmental design. Individuals working a high demand task reported more negative mood and less performance satisfaction than individuals working a low demand task. As expected, motivation was not affected by any manipulations. Performance appears to be affected by environmental color or view. When performing a low demand task, performance appears to worsen over time in the blue rather than the red environment. When working a high demand task in a red environment, performance was worse unless either a break or a scenic picture were present. These data suggest that blue is a calming color and red is a stimulating color, which may interact with other environmental factors. The impact of a scenic picture may serve a comparative process.
Spectra-structure relationships in the near ultraviolet optical activity of chiral barbituric acid derivatives

The chiroptical properties associated with then-π* (singlet-singlet) transitions in dissymmetric barbituric acid derivatives are examined on the basis of two theoretical models. The lower singlet excited states of unsubstituted and alkyl substituted barbituric acids are calculated on the semi-empirical CNDO/S-CI molecular orbital model, and the spectroscopic properties associated with transitions to these states are computed. In the structures we examined, threen-π* transitions are found at λ>220 nm, two of which are nearly degenerate. Each of these transitions is computed to be strongly magnetic dipole allowed and to be forbidden or very weak (depending upon the exact symmetry and geometry of the trioxopyrimidine moiety) in electric dipole radiation. Contributions from chiral distortions within the trioxopyrimidine chromophoric system to the rotatory strengths of the three lowest energyn-π* transitions are calculated directly from wave functions obtained by the CNDO/S-CI method. Contributions to then-π* rotatory strengths arising from “vicinal” interactions between the trioxopyrimidine chromophore and asymmetric substituent groups are calculated by a perturbation method based on an independent systems representation of the optically active compounds. Various spectra-structure relationships are considered and correlations between experimental data and theoretically calculated results are examined.
Modeling Helical Structures in Relativistic Jets

Many jets exhibit twisted helical structures. Where superluminal motions are detected, jet orientation and pattern/flow speed are considerably constrained. In this case modeling efforts can place strong limits on conditions in the jet and in the external environment. This can be done by modeling the spatial development of helical structures that are sensitively dependent on these conditions. Along an expanding jet, this sensitivity manifests itself in predictable changes in pattern speed and observed wavelength. In general, twists of low frequency relative to the local resonant frequency are advected along the expanding jet into a region in which the twist frequency is high relative to the local resonant frequency. The wave speed can be very different in these two frequency regimes. Potential effects include helical twists with a nearly constant apparent wavelength, an apparent wavelength scaling approximately with the jet radius for up to 2 orders of magnitude of jet expansion, or multiple twist wavelengths with vastly different intrinsic scale and vastly different wave speeds that give rise to similar observed twist wavelengths but with very different observed motion. In this paper I illustrate the basic intrinsic and observed behavior of these structures and show how to place constraints on jet conditions in superluminal jets using the apparent structures and motions in the inner 3C 120 jet.