cssi/SciSciGPT-SciSciNet huggingface dataset:
Engineering for systems using large scale integration

Our experience in designing and producing over 100 different MOS large scale arrays (LSA's) for a variety of systems and customers has led to a number of changes in our pattern of engineering operations. We have found that the major increase in device complexity called for in LSA's requires extensive use of design aids for acceptable development schedules and costs. In turn, the generation and use of these design aids tie device designers and the logic/system designer closely together.
A comprehensive analysis of normal variation and disease-causing mutations in the human DSPP gene†‡

Within nine dentin dysplasia (DD) (type II) and dentinogenesis imperfecta (type II and III) patient/families, seven have 1 of 4 net –1 deletions within the ∼2-kb coding repeat domain of the DSPP gene while the remaining two patients have splice-site mutations. All frameshift mutations are predicted to change the highly soluble DSPP protein into proteins with long hydrophobic amino acid repeats that could interfere with processing of normal DSPP and/or other secreted matrix proteins. We propose that all previously reported missense, nonsense, and splice-site DSPP mutations (all associated with exons 2 and 3) result in dominant phenotypes due to disruption of signal peptide-processing and/or related biochemical events that also result in interference with protein processing. This would bring the currently known dominant forms of the human disease phenotype in agreement with the normal phenotype of the heterozygous null Dspp (–/+) mice. A study of 188 normal human chromosomes revealed a hypervariable DSPP repeat domain with extraordinary rates of change including 20 slip-replication indel events and 37 predominantly C-to-T transition SNPs. The most frequent transition in the primordial 9-basepair (bp) DNA repeat was a sense-strand CpG site while a CpNpG (CAG) transition was the second most frequent SNP. Bisulfite-sequencing of genomic DNA showed that the DSPP repeat can be methylated at both motifs. This suggests that, like plants and some animals, humans methylate some CpNpG sequences. Analysis of 37 haplotypes of the highly variable DSPP gene from geographically diverse people suggests it may be a useful autosomal marker in human migration studies. Hum Mutat 0, 1–13, 2008. Published 2008, Wiley-Liss, Inc.
High-Redshift Galaxy Outflows and the Formation of Dwarf Galaxies

We examine the effects of galaxy outflows on the formation of dwarf galaxies in numerical simulations of the high-redshift universe. Using a smoothed particle hydrodynamic code, we conduct two detailed simulations of a (5.2 Mpc h-1)3 comoving volume of the universe. In both simulations we implement simple, well-motivated models of galaxy identification and star formation, while our second simulation also includes a simple "blow-out" model of galaxy outflows in which supernova driven winds from newly formed disk galaxies punch out and shock the intergalactic medium while leaving the host galaxies intact. A direct comparison between these simulations suggests that there are two major mechanisms by which outflows affect dwarf formation. First, the formation of an outflow slows down the further accretion of gas onto a galaxy, causing an overall decrease of approximately 50% in the total gas mass accreted by the objects in our simulations. Additionally, our simulations uncover a significant population of ~109 M☉ objects whose formation is suppressed by the mechanism of "baryonic stripping," in which outflows from early galaxies strip the gas out of nearby overdense regions that would have otherwise later formed into dwarf galaxies. This mechanism may be important in explaining the observed discrepancy between the number of dwarf galaxies predicted and observed in the local group and provide a natural explanation for the formation of empty halos which may be required by the existence of the extremely gas-poor extragalactic high-velocity clouds.
Thiele's ester as a reagent in organic synthesis. Preparation of pentacyclo[5.4.0.02,5.03,10.04,8]undecane-10-carboxylic acid

Abstract Succinyl cleavage of the C(2)–C(5) σ-bond in dimethyl pentacyclo[5.3.0.0 2,5 .0 3,9 .0 4,8 ]decane-2,5-dicarboxylate, 2 , afforded a tetracyclic diester, 3 (22–26%), along with two minor reaction products ( 4 and 5 ). Dieckmann condensation of 3 produced a mixture of 6a and 6b (67%). Wolff-Kishner reduction of the mixture of 6a and 6b thereby obtained afforded a mixture of products from which the title compound, 7b , could be isolated in 63% yield by fractional recrystallization. The structures of 3 , 4 and 7b were established unequivocally via X-ray crystallographic methods.
DETECTING OCEANS ON EXTRASOLAR PLANETS USING THE GLINT EFFECT

Glint, the specular reflection of sunlight off Earth's oceans, may reveal the presence of oceans on an extrasolar planet. As an Earth-like planet nears crescent phases, the size of the ocean glint spot increases relative to the fraction of the illuminated disk, while the reflectivity of this spot increases. Both effects change the planet's visible reflectivity as a function of phase. However, strong forward scattering of radiation by clouds can also produce increases in a planet's reflectivity as it approaches crescent phases, and surface glint can be obscured by Rayleigh scattering and atmospheric absorption. Here, we explore the detectability of glint in the presence of an atmosphere and realistic phase-dependent scattering from oceans and clouds. We use the NASA Astrobiology Institute's Virtual Planetary Laboratory three-dimensional line-by-line, multiple-scattering spectral Earth model to simulate Earth's broadband visible brightness and reflectivity over an orbit. Our validated simulations successfully reproduce phase-dependent Earthshine observations. We find that the glinting Earth can be as much as 100% brighter at crescent phases than simulations that do not include glint, and that the effect is dependent on both orbital inclination and wavelength, where the latter dependence is caused by Rayleigh scattering limiting sensitivity to the surface. We show that this phenomenon may be observable using the James Webb Space Telescope paired with an external occulter.
Minimum Impulse Three-Body Trajectories

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1973.
Composition and behaviors of probabilistic I/O automata

Abstract We augment the I/O automaton model of Lynch and Tuttle with probability, as a step toward the ultimate goal of obtaining a useful tool for specifying and reasoning about asynchronous probabilistic systems. Our new model, called probabilistic I/O automata , preserves the fundamental properties of the I/O automaton model, such as the asymmetric treatment of input and output and the pleasant notion of asynchronous composition. For certain classes of probabilistic I/O automata, we show that probabilistic behavior maps , which are an abstract representation of I/O automaton behavior in terms of a certain expectation operator, are compositional and fully abstract with respect to a natural notion of probabilistic testing.
Real-time wavefront correction through Bragg diffraction of light by sound waves.

The direction of propagation and phase of a light wave diffracted successively by two sound waves of the same frequency but different wavelengths can be controlled by varying the acoustic frequency and the relative phase of the sound waves. Because the Doppler frequency shifts produced by the two sound waves are of equal magnitude but opposite signs, they cancel each other, with the consequence that the diffracted-diffracted wave is coherent with the incident (or undiffracted) light. If a wavefront distorted by atmospheric turbulence is divided into subwavefronts, each subwavefront being planar, it can be corrected in real time if it is allowed to pass through an array of Bragg cells. Each cell carries two pairs of orthogonal sound waves to correct for tilts and phase errors of a corresponding subwavefront.
Ring Lithiation and Functionalization of Imidazol-2-ylidene-boranes

N,N′-Dialkyl and N,N′-diaryl imidazol-2-ylidene-boranes and trifluoroboranes are rapidly lithiated at C4 of the imidazole ring, and the resulting intermediates have been quenched with an assortment of electrophiles to provide ring-functionalized imidazol-2-ylidene-boranes. Further deprotonation and functionalization of C5 have been demonstrated. Deboronation of the products by treatment with triflic acid or iodine and then methanol opens a route to C4/C5 functionalized imidazolium salts and imidazol-2-ylidenes.
Automated, on-board terrain analysis for precision landings

Advances in space robotics technology hinge to a large extent upon the development and deployment of sophisticated new vision-based methods for automated in-space mission operations and scientific survey. To this end, we have developed a new concept for automated terrain analysis that is based upon a generic image enhancement platform|multi-scale retinex (MSR) and visual servo (VS) processing. This pre-conditioning with the MSR and the vs produces a "canonical" visual representation that is largely independent of lighting variations, and exposure errors. Enhanced imagery is then processed with a biologically inspired two-channel edge detection process, followed by a smoothness based criteria for image segmentation. Landing sites can be automatically determined by examining the results of the smoothness-based segmentation which shows those areas in the image that surpass a minimum degree of smoothness. Though the msr has proven to be a very strong enhancement engine, the other elements of the approach|the vs, terrain map generation, and smoothness-based segmentation|are in early stages of development. Experimental results on data from the Mars Global Surveyor show that the imagery can be processed to automatically obtain smooth landing sites. In this paper, we describe the method used to obtain these landing sites, and also examine the smoothness criteria in terms of the imager and scene characteristics. Several examples of applying this method to simulated and real imagery are shown.
Drell-Yan plus missing energy as a signal for extra dimensions

Abstract We explore the search sensitivity for signals of large extra dimensions at hadron colliders via the Drell-Yan process pp→l + l − + E / T X (l=e, μ ) where the missing transverse energy is the result of escaping Kaluza-Klein gravitons. We find that one is able to place exclusion limits on the gravity scale up to 560 GeV at the Fermilab Tevatron, and to 4.0 (3.3) TeV at the CERN LHC, for n =3 (4) extra dimensions.
Preparation of meta-amidino-N,N-disubstituted anilines as potent inhibitors of coagulation factor Xa ☆

The serine protease factor Xa is a critical enzyme in the blood coagulation cascade. Recently, the inhibition of factor Xa has begun to emerge as an attractive strategy for the discovery of novel antithrombotic agents. Here we describe a series of meta-amidino-N,N-disubstituted anilines as structurally simple and very potent inhibitors of factor Xa.
Measuring the Impacts of Teachers II: Teacher Value-Added and Student Outcomes in Adulthood

Abstract Are teachers' impacts on students' test scores (value-added) a good measure of their quality? This question has sparked debate partly because of a lack of evidence on whether high value-ad...
Lead Oxide Coatings on Sol–Gel‐Derived Lead Lanthanum Zirconium Titanate Thin Layers for Enhanced Crystallization into the Perovskite Structure

An improved method is described for the sol-gel preparation of PLZT thin layers in the perovskite structure. The method uses a PbO cover coat. Details are reported for the sol-gel processing route and heat-treatment conditions. Through use of this method it is possible to prepare single-phase perovskite material with improved properties. The deleterious effect of additional phases--which are not present when a PbO cover coat is used--is attributed to Pb loss from the surface during thermal processing. Examples are given for PLZT thin layers integrated on Si with and without a PbO cover coat. The dielectric and ferroelectric properties were always found to be superior for coated structures.
A starvation-free access protocol for a full-duplex buffer insertion ring local area network

Abstract Of several existing designs for local area networks, the buffer insertion ring has been shown to provide higher throughputs, lower mean delays and greater spatial reuse than competing designs such as the token ring and slotted ring networks. However, one disadvantage is that the normally unregulated access scheme of the insertion ring allows for the phenomenon of “starvation” — when a network node has to wait too long before it can access the ring. In our work, we demonstrate that starvation is a serious problem and present a protocol to prevent it. It is shown that the new protocol is correct, stable and does not substantially degrade the otherwise efficient operation of the ring.
A sequence of discrete minimal energy configurations that does not converge in the weak-star topology

Abstract We demonstrate a set A and a value of s for which any sequence of N -point discrete minimal Riesz s -energy configurations on A does not have an asymptotic distribution in the weak-star sense as N tends to infinity.
Dichotomy for voting systems

Scoring protocols are a broad class of voting systems. Each is defined by a vector (@a"1,@a"2,...,@a"m), @a"1>[email protected]"2>=...>[email protected]"m, of integers such that each voter contributes @a"1 points to his/her first choice, @a"2 points to his/her second choice, and so on, and any candidate receiving the most points is a winner. What is it about scoring-protocol election systems that makes some have the desirable property of being NP-complete to manipulate, while others can be manipulated in polynomial time? We find the complete, dichotomizing answer: Diversity of dislike. Every scoring-protocol election system having two or more point values assigned to candidates other than the favorite-i.e., having @?{@a"i|2==2-is NP-complete to manipulate. Every other scoring-protocol election system can be manipulated in polynomial time. In effect, we show that-other than trivial systems (where all candidates alway tie), plurality voting, and plurality voting's transparently disguised translations-every scoring-protocol election system is NP-complete to manipulate.
Dependence of the a-Si:H defect density of states on the magnetic field profile of an electron cyclotron resonance microwave plasma

The magnetic field profile of an electron cyclotron resonance microwave plasma was systematically altered to determine subsequent effects on a-Si:H film quality. The mobility gap deep density ND deposition rate and light-to-dark conductivity were determined for the a-Si:H films. By variation of the magnetic field profile ND could be altered by more than an order of magnitude, from 1 × 1016 to 1 × 1017 cm−3 at 0.7 mTorr and 1 × 1016 to 5 × 1017 cm−3 at 5 mTorr as determined by junction capacitance techniques. Two deposition regimes were found to occur for the conditions of this study. Highly divergent magnetic fields resulted in poor quality a-Si:H, while for magnetic field profiles defining a more highly confined plasma, the a-Si:H was of device quality and relatively independent of the magnetic field configuration. The data is interpreted as a consequence of silane depletion for highly divergent magnetic field profiles.
PARALLEL ALGORITHMS FOR LONGEST INCREASING CHAINS IN THE PLANE AND RELATED PROBLEMS

Given a set of n points in the plane such that each point in is asscociated with a nonnegative weight, we consider the problem of computing the single-source longest increasing chains among the points in This problem is a generalization of the plannar maximal layers problem. In this paper, we present a parallel algorithm that computes the single-source longest incresing chains in the plane in time using processors in the CREW PRAM computational model. We also solve a related problem of computing the all-pairs longest paths in an n-node weighted planar st-graph, in time using CREW PRAM processors. Both of our parallel algorithms are improvement over the previously best known results.
Wading and jumping into a new job-exploring dynamics of knowledge flow for systems engineers

Engineering companies are growing increasingly concerned with identifying ways to effectively transfer knowledge, both to new employees and between employees who collaborate to develop new products. Effective knowledge capture is difficult in research and development contexts where design knowledge is rapidly changing and often poorly documented. This paper uses a case study at a small engineering company to suggest that effective knowledge transfer must be both relational (asking intelligent questions of mentors who are taxed for time) and procedural (using documentation to record how decisions are made). Cultural consensus analysis identifies two distinct cultural domains regarding effective socialization for new systems engineers. Waders advocate guided introduction, while Jumpers advocate immediate responsibility. These common themes for companies dealing with rapidly changing knowledge offer insights to scholars interested in studying the broader domain of anthropology of work.
Toward an understanding of dimensions, predictors, and the gender gap in written composition

We had 3 aims in the present study: (a) to examine the dimensionality of various evaluative approaches to scoring writing samples (e.g., quality, productivity, and curriculum-based measurement [CBM] writing scoring), (b) to investigate unique language and cognitive predictors of the identified dimensions, and (c) to examine gender gap in the identified dimensions of writing. These questions were addressed using data from 2nd- and 3rd-grade students (N = 494). Data were analyzed using confirmatory factor analysis and multilevel modeling. Results showed that writing quality, productivity, and CBM scoring were dissociable constructs but that writing quality and CBM scoring were highly related (r = .82). Language and cognitive predictors differed among the writing outcomes. Boys had lower writing scores than girls even after accounting for language, reading, attention, spelling, handwriting automaticity, and rapid automatized naming. Results are discussed in light of writing evaluation and a developmental model of writing.
A recognition principle for the existence of descent data

Suppose $$R\rightarrow S$$ is a faithfully flat ring map. Given an $$S$$ -module $$N$$ , does there exists some $$R$$ -module $$M$$ such that $$S\otimes _R M\cong N$$ ? In this paper we work out (as a special case of a more general question about extensions of comonads) a criterion for the existence of such an $$R$$ -module $$M$$ , under some reasonable hypotheses on the map $$R\rightarrow S$$ .
The Tolman Surface Brightness Test for the Reality of the Expansion. I. Calibration of the Necessary Local Parameters

Surface brightness averages are calculated at various metric radii in each galaxy in the sample. The definition of such radii by Petrosian uses ratios of observed surface photometric data. Petrosian radii have important properties for the Tolman test which are reviewed in this paper. The observed surface brightnesses are listed for 118 first-ranked cluster galaxies at Petrosian η radii of 1.0, 1.3, 1.5, 1.7, 2.0, and 2.5 mag. The three local diagnostic correlation diagrams are defined and discussed. We review the Tolman test and show that, although recipes from the standard cosmological model that already have the Tolman signal incorporated are required to calculate linear radii and absolute magnitudes from the observed data, the test is nevertheless free from the hermeneutical circularity dilemma occasionally claimed in the literature. The reasons are the observed mean surface brightness (1) is independent of any assumptions of cosmological model, (2) does not depend on the existence of a Tolman signal because it is calculated directly from the data using only angular radii and apparent magnitudes, and (3) can be used to search for the Tolman signal because it carries the bulk of that signal.
Genetic studies: look no further than your own backyard.

Abstract Eaves, I.A. et al. (2000) The genetically isolated populations of Finland and Sardinia may not be a panacea for linkage disequilibrium mapping of common disease genes. Nat. Genet . 25, 320–323Taillon-Miller, P. et al. (2000) Juxtaposed regions of extensive and minimal linkage disequilibrium in human Xq25 and Xq28. Nat. Genet . 25, 324–328
Synthesis of 2,3-Disubstituted Indoles via Palladium-Catalyzed Annulation of Internal Alkynes

The palladium-catalyzed coupling of 2-iodoaniline and the corresponding N-methyl, -acetyl, and -tosyl derivatives with a wide variety of internal alkynes provides 2,3-disubstituted indoles in good-to-excellent yields. The best results are obtained by employing an excess of the alkyne and a sodium or potassium acetate or carbonate base plus 1 equiv of either LiCl or n-Bu4NCl, occasionally adding 5 mol % PPh3. The yields with LiCl appear to be higher and more reproducible than those obtained with n-Bu4NCl. The process is quite general as far as the types of substituents which can be accommodated on the nitrogen of the aniline and the two ends of the alkyne triple bond. The reaction is quite regioselective, placing the aryl group of the aniline on the less sterically hindered end of the triple bond and the nitrogen moiety on the more sterically hindered end. This methodology readily affords 2-silylindoles, which can be easily protodesilylated, halogenated, or reacted with alkenes and Pd(OAc)2 to produce 3-su...
FAST, SELF-NULLING SPECTROSCOPIC ELLIPSOMETER : INSTRUMENTATION AND APPLICATION

The advantages of rapid spectral scanning have been combined with the inherent accuracy of a compensating ellipsometer operated in the polarizer- compensator-sample-analyzer configuration. Wavelength is varied over the visible-UV (370-720 nm) at a maximum rate of 114 nm/s by rotating a continuously- variable interference filter. A three-reflection Fresnel rhomb serves as the achromatic quarter-wave compensator. A microcomputer is used to collect spectroscopic measurements, perform instrument calibrations, digital filtering and interpret data. Wavelength-independent parameters of multiple-film optical models have been determined by treating measurements of delta and psi at different wavelengths as independent measurements. Experimental and predicted ellipsometer measurements are compared by use of statistical techniques for the determination of optimum values and confidence limits of model parameters.
Lock Cohorting: A General Technique for Designing NUMA Locks

Multicore machines are quickly shifting to NUMA and CC-NUMA architectures, making scalable NUMA-aware locking algorithms, ones that take into account the machine's nonuniform memory and caching hierarchy, ever more important. This article presents lock cohorting, a general new technique for designing NUMA-aware locks that is as simple as it is powerful. Lock cohorting allows one to transform any spin-lock algorithm, with minimal nonintrusive changes,into a scalable NUMA-aware spin-lock. Our new cohorting technique allows us to easily create NUMA-aware versions of the TATAS-Backoff, CLH, MCS, and ticket locks, to name a few. Moreover, it allows us to derive a CLH-based cohort abortable lock, the first NUMA-aware queue lock to support abortability. We empirically compared the performance of cohort locks with prior NUMA-aware and classic NUMA-oblivious locks on a synthetic micro-benchmark, a real world key-value store application memcached, as well as the libc memory allocator. Our results demonstrate that cohort locks perform as well or better than known locks when the load is low and significantly out-perform them as the load increases.
THE FALSE POSITIVE RATE OF KEPLER AND THE OCCURRENCE OF PLANETS

The Kepler mission is uniquely suited to study the frequencies of extrasolar planets. This goal requires knowledge of the incidence of false positives such as eclipsing binaries in the background of the targets, or physically bound to them, which can mimic the photometric signal of a transiting planet. We perform numerical simulations of the Kepler targets and of physical companions or stars in the background to predict the occurrence of astrophysical false positives detectable by the mission. Using real noise level estimates, we compute the number and characteristics of detectable eclipsing pairs involving main-sequence stars and non-main-sequence stars or planets, and we quantify the fraction of those that would pass the Kepler candidate vetting procedure. By comparing their distribution with that of the Kepler Objects of Interest (KOIs) detected during the first six quarters of operation of the spacecraft, we infer the false positive rate of Kepler and study its dependence on spectral type, candidate planet size, and orbital period. We find that the global false positive rate of Kepler is 9.4%, peaking for giant planets (6-22 R ⊕) at 17.7%, reaching a low of 6.7% for small Neptunes (2-4 R ⊕), and increasing again for Earth-size planets (0.8-1.25 R ⊕) to 12.3%. Most importantly, we also quantify and characterize the distribution and rate of occurrence of planets down to Earth size with no prior assumptions on their frequency, by subtracting from the population of actual Kepler candidates our simulated population of astrophysical false positives. We find that 16.5% ± 3.6% of main-sequence FGK stars have at least one planet between 0.8 and 1.25 R ⊕ with orbital periods up to 85 days. This result is a significant step toward the determination of eta-earth, the occurrence of Earth-like planets in the habitable zone of their parent stars. There is no significant dependence of the rates of planet occurrence between 0.8 and 4 Earth radii with spectral type. In the process, we also derive a prescription for the signal recovery rate of Kepler that enables a good match to both the KOI size and orbital period distribution, as well as their signal-to-noise distribution.
Deformed preprojective algebras and symplectic reflection algebras for wreath products

Abstract We determine the PBW deformations of the wreath product of a symmetric group with a deformed preprojective algebra of an affine Dynkin quiver. In particular, we show that there is precisely one parameter which does not come from deformation of the preprojective algebra. We prove that the PBW deformation is Morita equivalent to a corresponding symplectic reflection algebra for wreath product.
The Application of a Recyclable Organocatalytic System to the Asymmetric Domino Michael/Henry Reaction in Aqueous Media

A new type of pyrrolidine-based organocatalyst has been developed and found to be very effective for the domino Michael/Henry reaction in aqueous solvents. For the reaction involving pentane-1,5-dial and various nitroolefins, good yields (65–85%) and excellent enantioselectivities (99%) were obtained using this catalyst. In addition, the catalyst could be recycled up to four times resulting in good yields and up to seven times with good enantioselectivity.
Applications of molecular modeling in heterogeneous catalysis research

Abstract The application of molecular modeling in heterogeneous catalysis research as a complement to experimental studies has grown rapidly in recent years. This review summarizes methodologies for probing catalytic phenomena in terms of a hierarchical approach. The elements of the hierarchy are different computational methods at different time and length scales that may be linked together to answer questions spanning from the atomic to the macroscopic. At the most detailed level of description, quantum chemical calculations are used to predict the energies, electronic structures, and spectroscopic properties of small arrangements of atoms and even periodic structures. Atomistic simulations, using systems of hundreds or thousands of molecules, can be used to predict macroscopic thermodynamic and transport properties, as well as preferred molecular geometries. At the longest time and length scales, continuum engineering modeling approaches such as microkinetic modeling are used to calculate reaction rates, reactant conversion, and product yields and selectivities, using model parameters predicted by the other levels of the hierarchy. We highlight some interesting recent results for each of these approaches, stress the need for integrating modeling at widely varying time and length scales, and discuss current challenges and areas for future development.
Probe for the strong parity violation effects at RHIC with three particle correlations

In non-central relativistic heavy ion collisions, \(\mathcal{P}\)-odd domains, which might be created in the process of the collision, are predicted to lead to charge separation along the system orbital momentum [1]. An observable, \(\mathcal{P}\)-even, but directly sensitive to the charge separation effect, has been proposed in Ref. [2] and is based on 3-particle mixed harmonics azimuthal correlations. We report the STAR measurements using this observable for Au+Au and Cu+Cu collisions at \(\sqrt {s_{NN} } \) = 200 and 62 GeV. The results are reported as function of collision centrality, particle separation in rapidity, and particle transverse momentum. Effects that are not related to parity violation but might contribute to the signal are discussed.
Raman and infrared spectra, conformational stability, barriers to internal rotation, vibrational assignment and ab initio calculations of trans-1-chloro-2-butene

Abstract Raman (3200 to 10 cm −1 ) and infrared (3200 to 50 cm −1 ) spectra have been recorded for the fluid and solid phases of trans -1-chloro-2-butene (crotyl chloride, trans -CH 3 CHCHCH 2 Cl), and a complete vibrational assignment is proposed. The fundamental asymmetric torsion for the more stable gauche conformer has been observed in the far infrared spectrum of the gas and has a hybrid contour centered at 82.5 cm −1 . The corresponding mode for the syn conformer (allylic chlorine atom oriented syn to the double bond) gives rise to a series of well defined C -type Q -branches beginning at 110.7 cm −1 and proceeding to lower frequencies. From these data the potential function governing internal rotation of the asymmetric top has been determined and the following potential coefficients have been obtained: V 1 = −371 ± 18, V 2 = −103 ± 9, V 3 = 662 − 30, V 4 = 123 ± 5, V 6 = −20 ± 12 cm −1 . This potential function has the gauche rotamer more stable by 267 ± 57 cm −1 (763 ± 163 cal mol −1 ). The gauche to gauche, gauche to syn, and syn to gauche barriers have been determined to be 518, 839, and 572 cm −1 , respectively. Similarly, the barrier governing internal rotation of the CH 3 group has also been determined from the far-infrared spectrum of the gas. All of these data are compared with the corresponding quantities obtained from ab initio Hartree—Fock gradient calculations employing the RHF/3-21G * , RHF/6-31G * and MP2/6-31G * basis sets. Additionally, complete equilibrium geometries have been determined for both rotamers. The results are discussed and compared with the corresponding quantities for some similar molecules.
Algorithms in number theory

Publisher Summary This chapter discusses algorithms that solve two basic problems in computational number theory—factoring integers into prime factors and finding discrete logarithms. In the factoring problem, one is given an integer n 1 and is asked to find the decomposition of n into prime factors. It is common to split this problem into two parts. The first is called primality testing: given n , it is determined whether n is prime or composite. The second is called factorization: if n is composite, a nontrivial divisor of n is to be calculated. In the discrete logarithm problem, one is given a prime number p , and two elements h, y of the multiplicative group F* p of the field of integers modulo p. The algorithms and their analyses depend on many different parts of number theory. Number theory is considered the purest of all sciences, and within number theory the hunt for large primes and for factors of large numbers has always been remote from applications, even to other questions of a number-theoretic nature.
Moral Concepts and Motivation

Author(s): Greenberg, Mark | Abstract: I first argue that standard versions of moral internalism are untenable in light of a type of example that has not previously been considered in metaethical discussions. As a consequence of having unusual views, a good-willed thinker could make moral judgments and recognize moral facts without having a disposition to be motivated to act accordingly (and without believing himself to have reasons for action). Moreover, on a familiar conception of irrationality as incoherence, the thinker in question need not be irrational, and it is not clear that there is a relevant conception of rationality on which he must be irrational. The first part of the paper therefore strengthens some of the most important arguments that have been taken to undermine internalism and support externalism.Next, however, I argue that these arguments seem to support externalism over internalism only because it is widely taken for granted that, if concepts are individuated in part by mental transitions, then a thinker cannot have a particular concept without having a disposition to make the concept’s individuating transitions. Considerations in the philosophy of mind, including the general type of example deployed in the first part of the paper, support rejecting that presupposition. Rejecting the presupposition makes visible a different understanding of internalism, one that is not vulnerable to some of the most influential arguments that have been taken to support externalism. According to the proposed position, a thinker who makes a moral judgment or recognizes a moral fact is subject to a conceptual requirement that he be motivated to act accordingly, but need not be disposed to satisfy that requirement. The second part of the paper thus argues that considerations independent of metaethics yield a position that neatly reconciles important internalist and externalist insights.Finally, in the last part of the paper, I begin the project of extending the arguments to internalism about reasons for action. I give reasons for thinking that patterns of attitudes that are typically taken to be paradigmatic of irrationality -- for example, believing that one ought, all things considered, to take a particular action but not being motivated to do so -- may not be irrational if they are the product of unusual views.
Synthesis and rearrangements of ortho-selenonium phenoxides

Abstract A new class of selenonium zwitterions is prepared from the ortho- substitution of phenols with diphenylselenium bis(trifluoroacetate) 1 . The zwitterions undergo a novel thermal rearrangement to produce diaryl ethers.
Observational implications of gamma-ray burst afterglow jet simulations and numerical light curve calculations

We discuss jet dynamics for narrow and wide gamma-ray burst (GRB) afterglow jets and the observational implications of numerical simulations of relativistic jets in two dimensions. We confirm earlier numerical results that sideways expansion of relativistic jets during the bulk of the afterglow emission phase is logarithmic in time and find that this also applies to narrow jets with half opening angle of 0.05 rad. As a result, afterglow jets remain highly nonspherical until after they have become nonrelativistic. Although sideways expansion steepens the afterglow light curve after the jet break, the jet edges becoming visible dominates the jet break, which means that the jet break is sensitive to the observer angle even for narrow jets. Failure to take the observer angle into account can lead to an overestimation of the jet energy by up to a factor of four. This weakens the challenge posed to the magneter energy limit by extreme events such as GRB090926A. Late-time radio calorimetry based on a spherical nonrelativistic outflow model remains relevant when the observer is approximately on-axis and where differences of a few in flux level between the model and the simulation are acceptable. However, this does not imply sphericity of the outflow and therefore does not translate to high observer angles relevant to orphan afterglows. For more accurate calorimetry and in order to model significant late-time features such as the rise of the counterjet, detailed jet simulations remain indispensable.
Laser safety features of eye shields

Background and Objective A number of lasers are available for cutaneous periorbital surgery, yet not all eye shields are appropriate for all applications. We tested a variety of commercially available eye shields to assess their safety features. Study Design/Materials and Methods Six commercially available eye protectors were studied. A focused laser was incident upon the shield, and the intensity and exposure duration required for visible damage to the shield were measured. We then measured the temperature on the underside of the eye shield during exposure from the laser. Time-dependent temperature measurements were made with a type-T thermocouple fixed to the eye shield with silicon grease. Results Thermal response curves and rates of warming for each of the six eye shields were generated. Plastic shields showed significant thermal damage with most of the lasers tested. The metallic shields warmed more slowly and to a lesser degree. Conclusion Overall, the metallic eye shields had the most acceptable safety profile. Many of the plastic shields exhibited significant thermal damage, and therefore we discourage their use in periorbital laser surgery. © 1996 Wiley-Liss, Inc.
Bis(silyl)chelat-Komplexe des Eisens

The reaction of Fe2(CO)9 with 1,2-bis(dimethylsilyl)benzene, 1,2,4,5-tetrakis(dimethylsilyl)benzene and vic-tetrakis(dimethylsilyl)benzene affords bis(silyl)chelate complexes of iron.
Emerging role of kinase-targeted strategies in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is a malignancy of mature B cells that depend on host factors in the tissue microenvironment for survival and proliferation. In vitro, CLL cells rapidly undergo apoptosis unless microenvironmental factors are provided that support their survival. Signaling pathways activated in the microenvironment in vivo include the B-cell receptor (BCR) and NF-κB pathways. Thus, CLL is a disease “addicted to the host” and is dependent on pathways that promote normal B-cell development, expansion, and survival; this is particularly true in the case of the BCR signaling cascade. Small-molecule inhibitors of kinases that are essential for BCR signal transduction abrogate the stimulating effects of the microenvironment on CLL cells. The orally administered tyrosine kinase inhibitors fostamatinib and ibrutinib and the phosphatidylinositol 3-kinase inhibitor GS-1101 have induced impressive responses in relapsed and refractory CLL patients, mostly with moderate side effects. Reductions in lymphadenopathy and splenomegaly are seen within weeks and are frequently accompanied by a transient rise in absolute lymphocyte count that is asymptomatic and probably the result of changes in CLL cell trafficking. This review discusses the biologic basis for kinase inhibitors as targeted therapy of CLL and summarizes the exciting early clinical experience with these agents.
Le INTERFERON PRODUCTION BY HUMAN FIBROBLASTS

Abstract Human leukocyte ( Le ) and fibroblast ( F ) interferons differ in antigenic properties, physicochemical characteristics, and activity on cells of heterologous species. Previous work from this laboratory showed that two human foreskin fibroblast strains can produce either F interferon alone or both F and Le interferons, depending on the nature of the inducer. The present study demonstrates that both the cell type and the inducer determine the proportion of Le interferon produced by human fibroblast strains. Of eight strains tested, the human GM-258 strain, which is trisomic for chromosome 21, produced the highest absolute and relative amounts of Le interferon after Newcastle disease virus (NDV) inoculation. However, there was no correlation between Le interferon production and number of copies of chromosome 21 in other cell strains examined. Although both NDV and vesicular stomatitis virus (VSV) induced a substantial proportion of Le interferon in GM-258 cells, little or no Le interferon was induced in the same cells by polyinosinic-polycytidylic acid (poly(I)·poly(C) under five different conditions. In GM-258 cells induced with NDV, it was possible to partially manipulate the relative proportion of F and Le interferons and the time at which they were made by altering the conditions of induction. The percentage of Le interferon was increased by decreasing the multiplicity of infection or irradiating the virus with ultraviolet light. Kinetics of F and Le interferon production after different modes of NDV inoculation paralleled each other closely. F and Le interferon production was inhibited to similar degrees in the presence of the glycosylation inhibitors 2-deoxy- d -glucose and d -glucosamine. The bovine EBTr cell strain was used for the selective assay of Le interferon. These cells were as sensitive to Le interferon as human diploid fibroblasts. In contrast, less than 0.1% of human F interferon activity crossed the species line in EBTr cells. Le and F interferons produced by NDV-induced GM-258 cells were physically separated by affinity chromatography on immobilized anti- Le and anti- F globulins. On sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), the Le interferon component produced in GM-258 cells formed two separate peaks (with molecular weights of approximately 18,000 and 25,000), closely resembling a control Le interferon preparation. In contrast, the F interferon moiety made in GM-258 cells formed a single peak on SDS-PAGE, as did control F interferon (molecular weight approximately 26,000).
Itinerant Half-Metal Spin-Density-Wave State on the Hexagonal Lattice

We consider electrons on a honeycomb or triangular lattice doped to the saddle point of the band structure. We assume the system parameters are such that spin density wave (SDW) order emerges below a temperature ${T}_{N}$ and investigate the nature of the SDW phase. We argue that at $T\ensuremath{\le}{T}_{N}$, the system develops a uniaxial SDW phase whose ordering pattern breaks $O(3)\ifmmode\times\else\texttimes\fi{}{Z}_{4}$ symmetry and corresponds to an eight-site unit cell with nonuniform spin moments on different sites. This state is a half-metal---it preserves the full original Fermi surface, but has gapless charged excitations in one spin branch only. It allows for electrical control of spin currents and is desirable for nanoscience.
Wear Analysis of Head-Disk Interface During Contact

To achieve a higher storage density in a hard disk drive, the fly height of the air bearing slider, as part of the magnetic spacing, has to be minimized. At an ultralow fly height, the intermittent-continuous contact at the head-disk interface (HDI) is unavoidable and directly affects the mechanical and magnetic performance of the hard disk drive, and is of great interest. The HDI wear has a nonlinear and time-varying nature due to the change of contact force and roughness. To predict the HDI wear evolution, an iterative model of Coupled Head And Disk (CHAD) wear, is developed based on the contact mechanics. In this model, a composite transient wear coefficient is adopted and multiple phases of the wear evolution are established. A comprehensive contact stiffness is derived to characterize the contact at the HDI. The abrasive and adhesive wear is calculated based on the extended Archard's wear law. The plastic and elastic contact areas are calculated with a three-dimensional (3D) sliding contact model. Based on the CHAD wear model, for the first time, the coupling between head and disk wear evolutions is thoroughly investigated. Accelerated wear tests have also been performed to verify the disk wear effect on the slider wear. A wear coefficient drop with time is observed during the tests and it is attributed to a wear mechanism shift from abrasive to adhesive wear A shift in the type of contact from plastic to elastic accounts for the wear mechanism change.
Stable clusters in the condensed state and some possibilities for gas phase clusters

The classical naked cluster ions of the post-transition elements that are stable in solid compounds and their lower charged analogues observed in mixed metal beams reflect the reduced number of good bonding orbitals. New cluster ions of indium that are hypoelectronic (fewer than 2n+2 skeletal bonding electrons) because of distortions or the bonding of heterometal atoms within the clusters are described. A large family of new, orbital-rich clusters of the group III and IV transition metals sheathed by halide are all centered by a wide variety of heteroatoms. Factors in their stability, possible analogous naked cluster targets, and some calculations are considered.
A model-data weak formulation for simultaneous estimation of state and model bias

Abstract We introduce a Petrov–Galerkin regularized saddle approximation which incorporates a “model” (partial differential equation) and “data” (M experimental observations) to yield estimates for both state and model bias. We provide an a priori theory that identifies two distinct contributions to the reduction in the error in state as a function of the number of observations, M: the stability constant increases with M; the model-bias best-fit error decreases with M. We present results for a synthetic Helmholtz problem and an actual acoustics system.
Saturation of phase breaking in an open ballistic quantum dot

Abstract One of the key parameters for the observation of quantum interference effects in mesoscopic systems is the phase-breaking time τ φ . While there have been many measurements of this important phase-breaking time in diffusive mesoscopic structures, there have been relatively few studies of phase breaking in zero-dimensional structures. Here, a saturation of the phase-breaking time at low temperatures is found, with a decay at higher temperatures generally of the form of T −2/3 . Variation with dot size suggests a scaling in which the phase-breaking interaction is described by the total number of electrons N = nA within the dot.
Immigrant-trade links, transplanted home bias and network effects

Macro-level data for the US and 73 trading partners spanning the years 1980 to 2001 is used with a gravity specification to investigate the influence of immigration on bilateral trade. Prior research has identified immigrant stocks as a significant determinant of trade; however, this study indicates that the US immigrant-trade link is driven by immigration from relatively low income countries. A 10% increase in the immigrant stock is found to generate respectively 4.7 and 1.5% increases in domestic imports from and exports to the typical low income home country. The observed link is decomposed into two hypothesized channels–network effects and transplanted home bias. Considerable variation in per-immigrant trade effects is found across home countries: imports from the typical low income home country are estimated to increase by up to $2057 due to transplanted home bias and by as much as $2967 as a result of network effects, while exports rise by up to $910 as a result of networks.