cssi/SciSciGPT-SciSciNet huggingface dataset:
Recent advances in heterogeneous catalysts for bio-oil upgrading via “ex situ catalytic fast pyrolysis”: catalyst development through the study of model compounds

Advances in heterogeneous catalysis are driven by the structure–function relationships that define catalyst performance (i.e., activity, selectivity, lifetime). To understand these relationships, cooperative research is required: prediction and analysis using computational models, development of new synthetic methods to prepare specific solid-state compositions and structures, and identification of catalytically active site(s), surface-bound intermediates, and mechanistic pathways. In the application of deoxygenating and upgrading biomass pyrolysis vapors, a fundamental understanding of the factors that favor C–O bond cleavage and C–C bond formation is still needed. In this review, we focus on recent advances in heterogeneous catalysts for hydrodeoxygenation of biomass pyrolysis products. Focus is placed on studies that made use of model compounds for comparisons of catalysts and the reaction networks they promote. Applications of transition metal sulfide catalysts for deoxygenation processes are highlighted, and compared to the performances of noble metal and metal carbide, nitride, and phosphide catalysts. In general, it is found that bifunctional catalysts are required for deoxygenation in a single reactor, with bifunctionality achieved on the catalyst or in conjunction with the catalyst support. Catalysts that activate hydrogen well will be preferred for ex situ catalytic pyrolysis conditions (upgrading downstream of pyrolysis reactor prior to condensation of bio-oil, pressures near atmospheric, temperatures between 350–500 °C). Supports that limit chemisorption of large reactants (leading to blockage of catalyst sites) should be employed. Finally, the stability of the catalyst and support in high-steam and low hydrogen-to-carbon environments will be critical.
Dating young basalt eruptions by (U-Th)/He on xenolithic zircons

Accurate ages for young (e.g., Pleistocene) volcanic eruptions are important for geomorphic, tectonic, climatic, and hazard studies. Existing techniques can be time-consuming and expensive when many ages are needed, and in the case of K/Ar and 40Ar/39Ar dating, extraneous Ar often can limit precision, especially for continental basalts erupted through old lithosphere. We present a new technique for dating young basaltic eruptions by (U-Th)/He dating of zircons (ZHe) from crustal xenoliths. Single-crystal ZHe dates generally have lower precision than typical 40Ar/39Ar dates, but can be determined relatively easily on multiple replicate grain aliquots. We dated zircons from xenoliths from four volcanic centers in western North America: Little Bear Mountain, British Columbia (157 ± 3.5 [2.2%] ka weighted 95% confidence interval [CI], mean square of weighted deviates [MSWD] = 1.7) and Prindle Volcano, Alaska (176 ± 16 [8.9%] ka, MSWD = 13), in the northern Cordilleran volcanic province, and Fish Springs (273 ± 23 [8.6%], MSWD = 43) and Oak Creek (179 ± 8.1 [4.5%] ka, MSWD = 12), in the Big Pine Volcanic Field, California. All ZHe ages are either equivalent to or younger than previously determined K/Ar or 40Ar/39Ar ages, indicating the possibility of inherited 40Ar in some of the previous measurements. Zircons from upper crustal xenoliths in the Oak Creek and Fish Springs vents show poorer reproducibility and multiple apparent age distribution peaks, consistent with either intracrystalline U-Th zonation or <99.99% He degassing (assuming ca. 100 Ma pre-entrainment ZHe ages) of some zircons during magmatic entrainment. Removal of clear outliers in the older age-distribution peaks of the upper crustal xenoliths, most of which have extremely high U compared to other zircons of the same xenolith, improve the reproducibilities of Fish Springs to 4.7% (95% CI, MSWD = 4.8) and Oak Creek to 3.4% (95% CI, MSWD = 6.2). Coupled thermal and He diffusion modeling using appropriate xenolith sizes and magma temperatures and assuming published diffusion kinetics for zircon indicate that incomplete He degassing would require entrainment times <1 h. However, the observation of extremely high U in most zircons with older ages raises the possibility that zircons with high radiation dosages may have more retentive He diffusion characteristics.
The Diels-Alder reaction of 1-azadienes. The effect of an α-cyano substituent

Abstract N-Acyl-α-cyano-1-azadienes have been observed to be reactive and anti selective dienes in the intramolecular hetero Diels-Alder reaction.
Redevelopment Decisions for Commercial and Industrial Properties

Abstract The empirical work in this study serves as a test of the principle that redevelopment of a property will occur when the value of the existing bundle, plus demolition costs, is less than or equal to the price of vacant land. The probability of a commercial or industrial property being redeveloped is predicted using the difference in the estimated value of a parcel in its redeveloped state and its current use, correcting for sample selection bias. The empirical results support the hypothesis that land is redeveloped when its value in the redeveloped state is high relative to its value in the current use.
Life table technique in the analysis of response-time data from laboratory experiments on animals.

Abstract Life table technique is a statistical procedure recommended for use in the study of some response-time data from laboratory experiments on animals. The characteristics of such data are discussed. The text describes studies in various subject matter fields in which this method is applied. Several statistics may be derived by life table technique. In some investigations, the survivorship, mortality, or other response to any desired time in the experiment is estimated. The survivorship curve may serve to show the distribution of the responses. The average remaining lifetime of each group at selected time points in the study may be measured; also the average survival time, which is the average ramaining lifetime of each animal at the beginning of the experiment. Measures of sampling variability may be utilized to determine confidence limits and to test the statistical significance of results. Computation of a life table is explained in Part II.
THE ECONOMICS OF ATTENTION: MAXIMIZING USER VALUE IN INFORMATION-RICH ENVIRONMENTS

A distinguishing feature of the information era is the saliency of people's attention as a scarce resource. Unlike an earlier time when information was a valuable resource, its easy availability has shifted the focus to the limited bandwidth that people can devote to ubiquitous media and news. With this in mind, we introduce an automatic configuration mechanism that generates the most relevant information to be presented to limited attention users. It also guarantees to maximize their total expected utility from the information they receive. A computationally efficient algorithm is used to assign an index value to each information item, which then determines whether or not a given item appears in the top list presented to users at a given time.
Spinning mode sound propagation in ducts with acoustic treatment

Recent acoustic data show larger noise attenuations than predicted for acoustically treated aircraft engine inlets without splitter rings. A theoretical study of the acoustic propagation of spinning modes in acoustically treated open circular ducts is presented, and a suppressor with splitter rings was modeled by using the rectangular approximation to the annular duct. Theoretical models were used to determine optimum impedance and maximum attenuation for several spinning lobe numbers from 0 to 50. Results of the analysis indicate that for circular ducts the maximum possible attenuation and the optimum wall impedance are strong functions of the lobe number, and for annular ducts the attenuation and optimum wall impedance are insensitive to the spinning lobe number for well cut-on modes. These results explain why suppressors with splitter rings were quite effective in spite of the lack of detailed information on the noise source modal structure. Conversely, effective use of outer wall treatment alone will require expanded knowledge of the noise source structure. Approximate solutions are presented to help interpret the more exact theoretical results.
Near-Infrared Photometric Variability of Stars toward the Chamaeleon I Molecular Cloud

We present the results of a J, H, and K_s photometric monitoring campaign of a 0.°72 × 6° area centered on the Chamaeleon I star-forming region. Data were obtained on 15 separate nights over a 4 month time interval using the Two Micron All Sky Survey south telescope. Out of a total of 34,539 sources brighter than the photometric completeness limits (J = 16.0, H = 15.2, and K_s = 14.8), 95 exhibit near-infrared variability in one or more bands. The variables can be grouped into a population of bright, red objects that are associated with the Chamaeleon I association and a population of faint, blue variables that are dispersed over the full 6° of the survey and are likely field stars or older pre–main-sequence stars unrelated to the present-day Chamaeleon I molecular cloud. Ten new candidate members of Chamaeleon I, including eight brown dwarf candidates, have been identified based on variability and/or near-infrared–excess emission in the J-H versus H-K_s color-color diagram. We also provide a compendium of astrometry and J, H, and K_s photometry for previously identified members and candidate members of Chamaeleon I.
Stabilization of Extra Dimensions at Tree Level

By considering the effects of string winding and momentum modes on a time dependent background, we find a method by which six compact dimensions become stabilized naturally at the self-dual radius while three dimensions grow large.
Can one study heavy meson semileptonic decays on coarse anisotropic lattices

Abstract Exploratory studies of heavy meson semileptonic decays on coarse lattices using Symanzik improved glue, NRQCD heavy and D234 light quarks are discussed. Comparisons are made between calculations on anisotropic and isotropic lattices. We find evidence that having an anisotropy helps in extracting better signals at higher momenta.
Transient grating optical Kerr effect measurements of reorientational dynamics in liquids and liquid crystalline samples

Abstract Subpicosecond time resolved transient grating (TG) optical Kerr effect (OKE) experiments have been used to study the reorientational dynamics of biphenyl (BP) and pentylcyanobiphenyl (5CB). It is demonstrated how a polarization selective TG approach allows to separate and identify the contributions of various physical phenomena to the TG signal due to the different symmetry of the associated nonlinear susceptibility χ (3) tensor. BP shows anisotropic reorientational relaxation following a Debye-Stokes-Einstein behaviour. 5CB above its nematic-isotropic phase transition exhibits besides the well-known slow collective reorientational component with a critical temperature dependence fast contributions from relaxation within the pseudonematic domains which are temperature-independent over a large T-range.
A Collaborative and Interdisciplinary Computer Animation Course

David Ebert and Dan Bailey have developed an innovative and supportive environment for art and computer science students to collaborate on large scale graphics projects. This is exciting because in many academic institutions, students from these two disciplines never have a chance to meet each other, much less work together. Ebert hails from the CSEE Department at the University of Maryland Baltimore County, and Bailey is a member of the Visual Arts Department at UMBC. In this article, they discuss their choice of topics, their pedagogy and an evaluation of what worked.
Sparticle production in electron-photon collisions

Abstract We explore the potential of electron-photon colliders to measure fundamental supersymmetry parameters via the processes eγ→ e χ 0 (selectron-neutralino) and eγ→ ν χ − (sneutrino-chargino). Given the χ 0 and χ − masses from e+e− and hadron collider studies, cross section ratios σ(γ−)/σ(γ+) for opposite photon helicities determine the ν L , e L and e R masses, independent of the sparticle branching fractions. The difference m ν L 2 −m e L 2 measures MW2cos2β in a model-independent way. The e L and e R masses test the universality of soft supersymmetry breaking scalar masses. The cross section normalizations provide information about the gaugino mixing parameters.
Low Environmental Temperatures or Pharmacologic Agents That Produce Hypothermia Decrease Methamphetamine Neurotoxicity in Mice

Abstract Recently we have reported that methamphetamine (METH) neurotoxicity in rats depends on the environmental temperature. Here, we evaluate whether a cold environment (4°C) or drugs which affect chloride and glutamate ion channel function block METH neurotoxicity in mice. Adult male CD mice received METH i.p. (4 × 10 mg/kg METH at 23°C along with saline, 2.5 mg/kg ( + )-MK-801, 40 mg/kg phenobarbital or 2.5 mg/kg diazepam and either 4 × 10 or 4 × 20 mg/kg METH at 4°C). Multiple injections of METH (4 × 10 mg/kg, i.p.) at room temperature (23°C) produced a significant depletion of dopamine (DA) in striatum at 24, 72 h, 1 and 2 weeks. Three days post 4 × 10 mg/kg METH at 23°C, an 80% decrease in striatal dopamine (DA) occurred while the same dose at 4°C produced only a 20% DA decrease, and 4 X 20 mg/kg METH at 4°C produced a 54% DA decrease. At 23°C (+)MK-801 completely blocked while phenobarbital (40% decrease) and diazepam (65% decrease) partially blocked decreases in striatal DA produced by 4 × 10 mg/kg METH. Decreases in DOPAC and HVA were similar to the decreases in DA after METH and antagonists. Multiple injections of METH (4 × 10 mg/kg, i.p.) at room temperature also produced a significant depletion of serotonin (5-HT) in striatum at 24, 72 h, 1 and 2 weeks. This depletion of 5-HT at room temperature was blocked either by changing the environmental temperature to 4°C, or by pretreatment with MK-801, diazepam and phenobarbital. A similar pattern in the decreases of the 5-HT metabolite 5-HIAA was observed after METH treatment. Drugs which block METH toxicity, such as haloperidol (D2 receptors), pentobarbital and phenobarbital (chloride channels) and MK-801 (NMDA/glutamate receptors), do not necessarily have the same mechanism of action but may either induce hypothermia or block induction of hyperthermia. Therefore, it is not clear how much of their protection against METH neurotoxicity is due to the blockade of the hyperthermia produce by METH.
Joint ultra-wideband and signal strength-based through-building tracking for tactical operations

Accurate device free localization (DFL) based on received signal strength (RSS) measurements requires placement of radio transceivers on all sides of the target area. Accuracy degrades dramatically if sensors do not surround the area. However, law enforcement officers sometimes face situations where it is not possible or practical to place sensors on all sides of the target room or building. For example, for an armed subject barricaded in a motel room, police may be able to place sensors in adjacent rooms, but not in front of the room, where the subject would see them. In this paper, we show that using two ultra-wideband (UWB) impulse radios, in addition to multiple RSS sensors, improves the localization accuracy, particularly on the axis where no sensors are placed (which we call the x-axis). We introduce three methods for combining the RSS and UWB data. By using UWB radios together with RSS sensors, it is still possible to localize a person through walls even when the devices are placed only on two sides of the target area. Including the data from the UWB radios can reduce the localization area of uncertainty by more than 60%.
Passive Evolution of Galaxy Clustering

We present a numerical study of the evolution of galaxy clustering when galaxies flow passively from high redshift, respecting the continuity equation throughout. While passive flow is a special case of galaxy evolution, it allows a well-defined study of galaxy ancestry and serves as an interesting limit to be compared to nonpassive cases. We use dissipationless N-body simulations, assign galaxies to massive halos at z = 1 and 2 using various halo occupation distribution (HOD) models, and trace these galaxy particles to lower redshift while conserving their number. We find that passive flow results in an asymptotic convergence at low redshift in the HOD and in galaxy clustering on scales above ~3 h−1 Mpc for a wide range of initial HODs. As galaxies become less biased with respect to mass asymptotically with time, the HOD parameters evolve such that M1/Mmin decreases while α converges toward unity, where Ng(M) = exp (− Mmin/M) [ 1 + (M/M1)α] . The satellite populations converge toward the Poisson distribution at low redshift. The convergence is robust for different number densities and is enhanced when galaxies evolve from higher redshift. We compare our results with the observed luminous red galaxy (LRG) sample from SDSS that has the same number density. We claim that if LRGs have experienced a strict passive flow, their Ng(M) should be close to a power law with an index of unity in halo mass. Discrepancies could be due to dry galaxy merging or new members arising between the initial and the final redshifts. The spatial distribution of passively flowing galaxies within halos appears on average more concentrated than the halo mass profile at low redshift. The evolution of bias for passively flowing galaxies is consistent with linear bias evolution on quasi-linear as well as large scales.
Supersymmetry breaking, fermion masses and a small extra dimension

We present a supersymmetric model in which the observed fermion masses and mixings are generated by localizing the three generations of matter and the two Higgs fields at different locations in a compact extra dimension. Supersymmetry is broken by the shining method and the breaking is communicated to standard model fields via gaugino mediation. Quark masses, CKM-mixing angles and the {mu} term are generated with all dimensionless couplings of {Omicron}(1). All dimensionful parameters are of order the five-dimensional Planck scale except for the size of the extra dimension which is of order the GUT scale. The superpartner spectrum is highly predictive and is found to have a neutralino LSP over a wide range of parameter space. The resulting phenomenology and interesting extensions of the model are briefly discussed.
Synthesis and evaluation of 4-(substituted styryl/alkenyl)-3,5-bis(4-hydroxyphenyl)-isoxazoles as ligands for the estrogen receptor

A series of 3,5-bis (4-hydroxyphenyl) isoxazoles bearing a styryl/alkyl vinyl group at the 4-position were prepared and evaluated as ligands for the estrogen receptor-alpha (ERα). The target compounds were prepared using the Suzuki reaction to couple an iodo-isoxazole intermediate with a series of styryl/alkenyl boronic acids, followed by O-demethylation. The products were evaluated for their estrogen receptor-α ligand binding domain (ERα-LBD) binding affinity using a competitive binding assay. The 4-(4-hydroxystyryl) derivative 4h displays binding properties similar to those of the previously described pyrazole class of ER ligands, indicating that the ERα-LBD tolerates the presence of the added vinyl group at the 4-position of the isoxazole ring.
A Numerical method for general relativistic magnetohydrodynamics

This paper describes the development and testing of a general relativistic magnetohydrodynamic (GRMHD) code to study ideal MHD in the fixed background of a Kerr black hole. The code is a direct extension of the hydrodynamic code of Hawley, Smarr, & Wilson and uses Evans & Hawley constrained transport (CT) to evolve the magnetic fields. Two categories of test cases were undertaken. A one-dimensional version of the code (Minkowski metric) was used to verify code performance in the special relativistic limit. The tests include Alfven wave propagation, fast and slow magnetosonic shocks, rarefaction waves, and both relativistic and nonrelativistic shock tubes. A series of one- and two-dimensional tests were also carried out in the Kerr metric: magnetized Bondi inflow, a magnetized inflow test due to Gammie, and two-dimensional magnetized constant-l tori that are subject to the magnetorotational instability.
On the Eikonal approximation in AdS space

We explore the eikonal approximation to graviton exchange in AdS5 space, as relevant to scattering in gauge theories. We restrict ourselves to the regime where conformal invariance of the dual gauge theory holds, and to large 't Hooft coupling where the computation involves pure gravity. We give a heuristic argument, a direct loop computation, and a shock wave derivation. The scalar propagator in AdS3 plays a key role, indicating that even at strong coupling, two-dimensional conformal invariance controls high-energy four-dimensional gauge-theory scattering.
Constrained-Equilibrium Modeling of Methane Oxidation in Air

Rate-controlled constrained-equilibrium method has been further developed to model methane/air combustion. A set of constraints has been identified to predict the nonequilibrium evolution of the combustion process. The set predicts the ignition delay times of the corresponding detailed kinetic model to within 10% of accuracy over a wide range of initial temperatures (900 K–1200 K), initial pressures (1 atm–50 atm) and equivalence ratios (0.6–1.2). It also predicts the experimental shock tube ignition delay times favorably well. Direct integration of the rate equations for the constraint potentials has been employed. Once the values of the potentials are obtained, the concentration of all species can be calculated. The underlying detailed kinetic model involves 352 reactions among 60 H/O/N/C1-2 species, hence 60 rate equations, while the RCCE calculations involve 16 total constraints, thus 16 total rate equations. Nonetheless, the constrained-equilibrium concentrations of all 60 species are calculated at any time step subject to the 16 constraints.
Reaction Pathways of Biomass-Derived Oxygenates over Metals and Carbides: From Model Surfaces to Supported Catalysts

The conversion of lignocellulosic biomass-derived oxygenates into renewable fuels and chemicals requires the control of bond-scission sequences. For example, selective CO/CO bond scission is needed to reduce the oxygen content and thus increase the energy density to produce renewable fuels. On the other hand, the control of CC bond scission is desired for producing H2 and suppressing side products from CO/CO bond-scission reactions. In this review, recent advances in the utilization of bimetallic and metal carbide catalysts that demonstrate enhanced performance and/or low cost for the selective CC and CO/CO bond-scission reactions, are summarized. Furthermore, the importance of combining density function theory (DFT) calculations, microkinetic modeling, and ultrahigh vacuum (UHV) experiments on single-crystal model surfaces with reactor evaluations over the corresponding powder catalysts is illustrated. General trends and future opportunities for the control of bond-scission sequences of biomass-derived oxygenates are also discussed.
A Simple Catalytic Method for the Conversion of Aryl Bromides to Arylamines

summary, we have developed a facile and general catalytic method for the conversion of aryl bromides to arylamines, which works well for inter- and intramolecular processes. Particularly noteworthy features of this method include the experimental sim- plicity, the tin/boron-free conditions, and the broad substrate scope. Efforts to discover improved catalyst systems which op- erate under milder reaction conditions as well as to employ these methods in synthetic organic chemistry are in progress.[13, l4] Esper imen tal Procedure 3: A mixture of 2-bromonaphthalene (205 mg. 0.99 mmol), N-niethylhomoveratry- lamine (234 mg, 1.20 mmol), sodium rert-hutoxide (134 mg. 1.39 mmol) and [Pd- CI,(P(o-tolyl),),] (14 mg. 0.02 mmol) in toluene (8-9 mL) was heated under argon at 100 C for 3 h. Aftercooling to room temperature, the reaction mixture was taken up in Et,O (30-40 mL) and washed with brine (15-20 mL). The organic fraction was dried with MgSO,, and concentrated using a rotary evaporator. The crude material was purified by flash chromatography on silica gel using hexane (100 mL), 1iexane:EtOAc
Intelligible encoding of ASL image sequences at extremely low information rates

Abstract American Sign Language (ASL) is a gestural language used by the hearing impaired. This paper describes experimental tests with deaf subjects that compared the most effective known methods of creating extremely compressed ASL images. The minimum requirements for intelligibility were determined for three basically different kinds of transformations: (1) gray-scale transformations that subsample the images in space and time; (2) two-level intensity quantization that converts the gray scale image into a black-and-white approximation; (3) transformations that convert the images into black and white outline drawings (cartoons). In Experiment 1, five subjects made quality ratings of 81 kinds of images that varied in spatial resolution, frame rate, and type of transformation. The most promising image size was 96 × 64 pixels (height × width). The 17 most promising image transformations were selected for formal intelligibility testing: 38 deaf subjects viewed 87 ASL sequences 1–2 s long of each transformation. The most effective code for gray-scale images is an analog raster code, which can produce images with 0.86 normalized intelligibility (I) at a bandwidth of 2,880 Hz and therefore is transmittable on ordinary 3 KHz telephone circuits. For the binary images, a number of coding schemes are described and compared, the most efficient being an extension of the quadtree method, here termed binquad coding which yielded I = 0.68 at 7,500 bits per second (bps). For cartoons, an even more efficient polygonal transformation with a victorgraph code yielding, for connected straight line segments, is proposed, together with a vectorgraph code yielding, for example, I = 0.56 at 3,900 bps and I = 0.70 at 6,000 bps. Polygonally transformed cartoons offer the possibility of telephonic ASL communication at 4,800 bps. Several combinations of binary image transformations and encoding schemes offer I > 80% at 9,600 bps.
Improved Procedure for the Oxidative Cleavage of Olefins by OsO4−NaIO4

[reaction: see text] Oxidative cleavage of olefins by OsO(4)-NaIO(4) sometimes suffers from low yields due to the formation of side products. It is found that the addition of 2,6-lutidine can suppress the side reactions and dramatically improve the yield of this classic reaction.
Scaling of angular distributions in multiparticle production

We find that a simple scaling relation, -/sub x/ = deltaeta/R, is consistent with data on multiparticle production from 30 -- 400 GeV, where eta = -ln tan(theta/2) is the pseudorapidity of produced fast particles, /sub x/ is the average pseudorapidity of particles in excess of the hydrogen-target pseudorapidity distribution, and R = //sub H/ is the ratio of average multiplicity on a nuclear target to the average proton-proton multiplicity at equal energy. We find that the distance between the centroids of the hydrogen-target eta distribution and the excess-particle distribution deltaeta = /sub H/-/sub x/ = 1.74 +- 0.06 is independent of energy, target mass, and possibly projectile. This result implies that R increases with energy, and asymptotically is approximately proportional to ..nu.., the number of collisions of the projectile.
Interchannel nonlinear impairment compensation by advanced split-step method

Interchannel nonlinear impairments are one of the major limitations to the channel capacity and transmission distance in WDM systems. It is shown that nonlinear impairments arising from cross-phase modulation between two independent WDM channels can be compensated. Advanced digital back propagation algorithms based on advanced split step method allow for compensating inter-channel nonlinear impairments with low complexity. With the new algorithm, the complexity of compensating inter-channel impairments is comparable to the complexity required for intra-channel impairments.
Categories of Jordan Structures and Graded Lie Algebras

In the paper we describe the subcategory of the category of ℤ-graded Lie algebras which is equivalent to the category of Jordan pairs via a functorial modification of the Tits, Kantor, and Koecher TKK construction. For instance, we prove that L = L −1 ⊕ L 0 ⊕ L 1 can be constructed from a Jordan pair if and only if L 0 = [L −1, L 1] and the second graded homology group is trivial. Similar descriptions are obtained for Jordan triple systems and Jordan algebras. New functorial versions of the TKK construction are given for pairs and algebras.
Sobolev estimates for the complex Green operator on CR submanifolds of hypersurface type

Let \(M\) be a pseudoconvex, oriented, bounded and closed CR submanifold of \(\mathbb {C}^{n}\) of hypersurface type. Our main result says that when a certain \(1\)-form on \(M\) is exact on the null space of the Levi form, then the complex Green operator on \(M\) satisfies Sobolev estimates. This happens in particular when \(M\) admits a set of plurisubharmonic defining functions or when \(M\) is strictly pseudoconvex except for the points on a simply connected complex submanifold.
FURTHER EVIDENCE ON DIVIDEND YIELDS AND THE EX‐DIVIDEND DAY STOCK PRICE EFFECT

Ex-dividend day stock price behavior supports a tax clientele effect. This effect is still found after the Tax Reform Act of 1986. Results reflect an effective tax advantage for capital gains taxes payable at realization, versus dividend taxes due quarterly. Evidence also supports short-term trader participation in the ex-day phenomenon when the difference between dividend income and the ex-dividend-day price decrease exceeds transactions costs to trade. Results contradict prior research where a tax clientele effect is not found, but align with this prior research when including a small number of contaminated observations.
Efficient algorithms for bichromatic separability

A closed solid body separates one point set from another if it contains the former and the closure of its complement contains the latter. We present a near-linear algorithm for deciding whether two sets of n points in ℝ3 can be separated by a prism, near-quadratic algorithms for separating by a slab or a wedge, and a near-cubic algorithm for separating by a double wedge. The latter three algorithms improve the previous best known results by an order of magnitude, while the prism separability algorithm constitutes an improvement of two orders of magnitude.
The Grushko decomposition of a finite graph of finite rank free groups: an algorithm

A finitely generated group admits a decomposition, called its Grushko decomposition, into a free product of freely indecomposable groups. There is an algorithm to construct the Grushko decomposition of a finite graph of finite rank free groups. In particular, it is possible to decide if such a group is free.
Timing of Effort and Reward: Three-Sided Moral Hazard in a Continuous-Time Model

This paper studies a three-sided moral hazard problem with one agent exerting up-front effort and two agents exerting ongoing effort in a continuous-time model. The agents' efforts jointly affect the probability of survival and thus the expected cash flow of the project. In the optimal contract, the timing of payments reflects the timing of effort: payments for up-front effort precede payments for ongoing effort. Several patterns are possible for the cash allocation between the two agents with ongoing effort. In one case, where the two agents face equally severe moral hazard, they share the cash flow equally at each point of time. In another case, where the two agents have different severities of moral hazard, their payments are sequential. In a more general case, the two agents with ongoing effort first receive the cash flow alternately with an increasing frequency of switches and then divide the cash flow at each point of time. This study provides a framework for understanding a broad set of business-contracting issues. The characteristics suggested in the optimal contract help us analyze the causes of business failure such as the recent debacle of mortgage-backed securities.
Long Term Changes in U.S. Agricultural Output per Worker, 1800 to 1900

The nineteenth century was a period of expansion and transformation of American agriculture. While much is known about the process, the exact pace and timing of agricultural productivity change is still unresolved. The traditional view is one of continued progress in which output and productivity increased steadily, accelerating over the period. The Civil War is seen as a convenient turning point, and perhaps an episode of greater consequence. More recent work has raised doubts about this picture of steady and accelerating success. The extant statistics on farm output and its labor force indicate that the period before the Civil War had the superior record and experienced particularly rapid productivity growth between 1820 and 1840. This paper presents new estimates of agricultural output per worker, based on revised statistics of the farm labor force and farm gross product. These new figures present a picture of agricultural progress more like the traditional view. Farm productivity grew noticeably faster after the Civil War than before, and important changes appear to have occurred during the Civil War decade.
MODELING THE MULTIWAVELENGTH SPECTRA AND VARIABILITY OF 3C 66A IN 2003–2004

The BL Lac object 3C 66A was the target of an intensive multiwavelength monitoring campaign organized in 2003–2004. During the campaign, its spectral energy distribution (SED) was measured and flux measurements from radio to X-ray frequencies as well as upper limits in the very high energy (VHE) γ-ray regime were obtained. Here, we reproduce the SED and optical spectral variability pattern observed during our multiwavelength campaign using a time-dependent leptonic jet model. Our model could successfully simulate the observed SED and optical light curves and predict an intrinsic cutoff value for the VHE γ-ray emission at ~4 GeV implying the effect of the optical depth due to the intergalactic infrared background radiation (IIBR) to be negligible. Also, the contribution of external Comptonization (EIC), due to the presence of a broad-line region (BLR), in the emission of γ-ray photons could be significant early-on when the emission region is very close to the central engine but as it travels farther out, the production mechanism of hard X-ray and γ-ray photons becomes dominated by synchrotron self-Compton mechanism (SSC).
A Note on Interfirm Implications of Wages and Status

This paper does not have an abstract, but examines inter-firm implications of some prior explorations into the nature of wages and status by Robert Frank.
Cost-effective clustering

Small Beowulf clusters can effectively serve as personal or group supercomputers. In such an environment, a cluster can be optimally designed for a specific problem (or a small set of codes). We discuss how theoretical analysis of the code and benchmarking on similar hardware lead to optimal systems.
Consensus Tracking Under Directed Interaction Topologies: Algorithms and Experiments

Consensus tracking problems with, respectively, bounded control effort and directed switching interaction topologies are considered when a time-varying consensus reference state is available to only a subgroup of a team and the team members have only local interaction. A consensus tracking algorithm explicitly accounting for bounded control effort is proposed and analyzed under a directed fixed interaction topology. Furthermore, convergence analysis for a consensus tracking algorithm is provided when the time-varying consensus reference state is available to a dynamically changing subgroup of the team under directed switching inter-vehicle interaction topologies. Experimental results of a formation control application are demonstrated on a multi-robot platform to validate one of the proposed consensus tracking algorithms.
A Non-Phenomenological Account of Friction/Vibration Interaction in Rotary Systems

Using a nonlinear model of a two disk brake system, coupled equations of motion are found for their frictional interaction. The mathematical formulation relates the tribological events at micron scale and the macroscopic scale vibration response of a two-disk brake system. This is accomplished by a viscoelastic account of interaction at the micron scale, its statistical quantification through the approximate analytical representation of the statistical expectation of contact force and the introduction of the contact force into the macroscale dynamics of the two-disk system. Steady-state analysis of the system establishes the relation between friction torque and speed and supports observed behavior of many mechanical systems with friction. It is shown that, as a result of coupling of the macrosystem’s dynamics and contact, there are combinations of parameters at the micro- and macroscale that yield negative slope in friction torque/sliding speed relation, a well known source of dynamic instability. This results in an effective negative damping that tends to decrease with decrease in the normal load and/or increase in structural damping of the system.
Aspartato(1,2-cyclohexanediamine)platinum(II) complexes : synthesis and characterization; effects of minor impurities on antitumor activity

Abstract Aspartato(1,2-cyclohexanediamine)platinum(II) (ADP), where 1,2-cyclohexanediamine (DAC) is either trans-RR-, trans-SS-, meso-RS-, or a mixture of the three isomers (ADP mixture), has been synthesized and evaluated for antitumor activity. The structures of the complexes have been characterized by various spectroscopic techniques (IR, 1H, 13C, 195Pt and 2D-COSY (1H{1H}) and 2D-HETCOSY (1H{13C}) NMR). Purification and murine antitumor activity of the individual ADP isomers indicate that minor impurities in the ADP mixture have a significant effect on the potency of the platinum complexes.
Forbidden tangential orbit transfers between intersecting Keplerian orbits

The classical problem of tangential impulse transfer between coplanar Keplerian orbits is addressed. A completely analytic solution which does not rely on sequential calculation is obtained and this solution is used to demonstrate that certain choices of initial true anomaly can produce singularities in the parameters of the transfer orbit. A necessary and sufficient condition for the existence of such singularities is that the initial and final orbits intersect.
Update on the Model Based Systems Engineering on the Europa Mission Concept Study

In May 2012 the Europa study team delivered to NASA the final reports on three distinct concepts for exploring Europa on a limited budget. The depth and quality of these reports have been widely praised by independent reviewers as well as by our sponsor. The application of Model Based Systems Engineering (MBSE) techniques is credited with enabling the team to study three quite different mission concepts for the resources normally sufficient to study only one or two. The Europa MBSE infusion itself has been awarded the NASA Systems Engineering Excellence Award in 2012. The Europa team is now preparing for its Mission Concept Review and has reaffirmed and strengthened the MBSE application. Significant new capabilities have been completed, most importantly the Powered Equipment List (PEL) and the computation of scenario-based power and energy margins. This paper provides an update on the continued successful application of MBSE in the dynamic environment of early mission formulation, the significant new results produced and several additional lessons learned in the process.
Instability of Toroidal Magnetic Field in Jets and Plerions

Astrophysical jets and pulsar-fed supernova remnants (plerions) are expected to develop highly organized magnetic structures dominated by concentric loops of toroidal field, B. It has been argued that such structures could explain the polarization properties of some jets and contribute to their lateral confinement through magnetic tension forces. A concentric toroidal field geometry is also central to the Rees-Gunn model for the Crab Nebula, the archetypal plerion, and leads to the deduction that the Crab pulsar's wind must have a weak magnetic field. Yet this kind of equilibrium between magnetic and gas pressure forces, the "equilibrium Z-pinch" of the controlled fusion literature, is well known to be susceptible to disruptive localized instabilities, even when the magnetic field is weak and/or boundary conditions (e.g., a dense external medium) slow or suppress global modes. Thus, the magnetic field structures imputed to the interiors of jets and plerions are unlikely to persist for very long. To determine the growth rates of Z-pinch instabilities under astrophysical conditions, I derive a dispersion relation that is valid for the relativistic fluids of which jets and plerions may be composed, in the ideal magnetohydrodynamics (MHD) limit. The dominant instabilities are kink (m = 1) and pinch (m = 0) modes. The former generally dominate, destroying the concentric field structure and probably driving the system toward a more chaotic state in which the mean field strength is independent of radius (and in which resistive dissipation of the field may be enhanced). I estimate the timescales over which the field structure is likely to be rearranged and relate these to distances along relativistic jets and radii from the central pulsar in a plerion. I conclude that the central tenet of the Rees-Gunn model for the Crab Nebula, the existence of a concentric toroidal field well outside the pulsar wind's termination shock, is physically unrealistic. With this assumption gone, there is no dynamical reason to conclude that the magnetic energy flux carried by the pulsar wind is much weaker than the kinetic energy flux. Abandoning the principal conclusion of Rees & Gunn would resolve a long-standing puzzle in pulsar wind theory.
Comparative analysis of RNA sequencing methods for degraded or low-input samples

RNA-seq is an effective method for studying the transcriptome, but it can be difficult to apply to scarce or degraded RNA from fixed clinical samples, rare cell populations or cadavers. Recent studies have proposed several methods for RNA-seq of low-quality and/or low-quantity samples, but the relative merits of these methods have not been systematically analyzed. Here we compare five such methods using metrics relevant to transcriptome annotation, transcript discovery and gene expression. Using a single human RNA sample, we constructed and sequenced ten libraries with these methods and compared them against two control libraries. We found that the RNase H method performed best for chemically fragmented, low-quality RNA, and we confirmed this through analysis of actual degraded samples. RNase H can even effectively replace oligo(dT)-based methods for standard RNA-seq. SMART and NuGEN had distinct strengths for measuring low-quantity RNA. Our analysis allows biologists to select the most suitable methods and provides a benchmark for future method development.
Why does the Soviet economy appear to be allocatively efficient

(1990). Why does the Soviet economy appear to be allocatively efficient? Soviet Studies: Vol. 42, No. 2, pp. 259-268.
Sufficient burn-in for Gibbs samplers for a hierarchical random effects model

We consider Gibbs and block Gibbs samplers for a Bayesian hierarchical version of the one-way random effects model. Drift and minorization conditions are established for the underlying Markov chains. The drift and minorization are used in conjunction with results from J. S. Rosenthal [J. Amer. Statist. Assoc. 90 (1995) 558– 566] and G. O. Roberts and R. L. Tweedie [Stochastic Process. Appl. 80 (1999) 211–229] to construct analytical upper bounds on the distance to stationarity. These lead to upper bounds on the amount of burn-in that is required to get the chain within a prespecified (total variation) distance of the stationary distribution. The results are illustrated with a numerical example. 1. Introduction. We consider a Bayesian hierarchical version of the standard normal theory one-way random effects model. The posterior density for this model is intractable in the sense that the integrals required for making inferences cannot be computed in closed form. Hobert and Geyer (1998) analyzed a Gibbs sampler and a block Gibbs sampler for this problem and showed that the Markov chains underlying these algorithms converge to the stationary (i.e., posterior) distribution at a geometric rate. However, Hobert and Geyer stopped short of constructing analytical upper bounds on the total variation distance to stationarity. In this article, we construct such upper bounds and this leads to a method for determining a sufficient burn-in. Our results are useful from a practical standpoint because they obviate troublesome, ad hoc convergence diagnostics [Cowles and Carlin (1996) and
Problems with tunneling of thin shells from black holes

It is shown that exp(−2 Im(∫ p dr)) is not invariant under canonical transformations in general. Specifically for shells tunneling out of black holes, this quantity is not invariant under canonical transformations. It can be interpreted as the transmission coefficient only in the cases in which it is invariant under canonical transformations. Although such cases include alpha decay, they do not include the tunneling of shells from black holes. The simplest extension to this formula which is invariant under canonical transformations is proposed. However, it is shown that this gives half the correct temperature for black holes.
Carbamoyl radicals from Se-phenylselenocarbamates: Intramolecular additions to alkenes

Abstract A series of 5 exo -trig cyclizations of carbamoyl radicals generated from readily available Se-phenylselenocarbamates is reported. Kinetic studies indicate that the rate constant of this cyclization exceeds 1×10 8 s −1 in reveral cases.
PSPACE is provable by two provers in one round

We show that every language in PSPACE, or equivalently, every language accepted by an unbounded round interactive proof system, ha a 1-round, 2-prover interactive proof system with exponentially small error probability. To obtain this result, we prove the correctness of a simple but powerful method for parallelizing 2-prover interactive proof systems to reduce their error.
Off-the-wall Higgs in the universal Randall-Sundrum model

We outline a consistent Randall-Sundrum (RS) framework in which a fundamental 5-dimensional Higgs doublet induces electroweak symmetry breaking (EWSB). In this framework of a warped Universal Extra Dimension, the lightest Kaluza-Klein (KK) mode of the bulk Higgs is tachyonic leading to a vacuum expectation value (vev) at the TeV scale. The consistency of this picture imposes a set of constraints on the parameters in the Higgs sector. A novel feature of our scenario is the emergence of an adjustable bulk profile for the Higgs vev. We also find a tower of nontachyonic Higgs KK modes at the weak scale. We consider an interesting implementation of this ''Off-the-Wall Higgs'' mechanism where the 5-dimensional curvature-scalar coupling alone generates the tachyonic mode responsible for EWSB. In this case, additional relations among the parameters of the Higgs and gravitational sectors are established. We discuss the experimental signatures of the bulk Higgs in general, and those of the ''Gravity-Induced'' EWSB in particular.