cssi/SciSciGPT-SciSciNet huggingface dataset:
Four dimensional black hole microstates: from D-branes to spacetime foam

We propose that every supersymmetric four dimensional black hole of finite area can be split up into microstates made up of primitive half-BPS ``atoms''. The mutual non-locality of the charges of these ``atoms'' binds the state together. In support of this proposal, we display a class of smooth, horizon-free, four dimensional supergravity solutions carrying the charges of black holes, with multiple centers each carrying the charge of a half-BPS state. At vanishing string coupling the solutions collapse to a bound system of intersecting D-branes. At weak coupling the system expands into the non-compact directions forming a topologically complex geometry. At strong coupling, a new dimension opens up, and the solutions form a ``foam'' of spheres threaded by flux in M-theory. We propose that this transverse growth of the underlying bound state of constitutent branes is responsible for the emergence of black hole horizons for coarse-grained observables. As such, it suggests the link between the D-brane and ``spacetime foam'' approaches to black hole entropy.
The difficulty of applying the economics of time and ignorance

The Economics of Time & Ignorance (1985) is a key text within Austrian economics. Among the so-called “third generation” of modern Austrian economists, however, the book seems to have had very little impact compared to the notable influence it had upon the proceeding generation. Several possible reasons are considered, including a disagreement with the substantive claims made in Time & Ignorance or the possibility that Time & Ignorance has nothing to offer this generation. We challenge these potential explanations and, argue, that the root cause of this seeming neglect is the movement by this generation towards applied research, an area where Time & Ignorance has relatively less to offer.
The Halo beaming model for gamma-ray bursts

We consider a model for gamma-ray bursts (GRBs) from high-velocity neutron stars in the Galactic halo. In this model, bursters are born in the Galactic disk with large recoil velocities V${b V}$ -->r, and GRBs are beamed to within emission cones of half-angle b centered on V${b V}$ -->r. We describe scenarios for magnetically channeled GRBs that have such beaming characteristics. We then make detailed comparisons of this halo beaming model (HBM) to data from the Third BATSE Catalog and from the Pioneer Venus Orbiter experiment, for both GRB intensity and angular position distributions. Acceptable fits to observations of over 1000 bursts are obtained for b = 15°-30° and for a BATSE sampling depth of D ~ 180 kpc, which corresponds to a peak burst luminosity of ~1040 ergs s-1. Present data favor a truly isotropic (cosmological) model over the HBM but not by a statistically compelling margin (2 σ). The HBM makes the distinctive prediction that the galactocentric quadrupole moment cos2 Θ - $f {1}{3} $ --> for bright, nearby GRBs is large, even though the dipole moment cos Θ remains near zero. Bursters born in nearby external galaxies, such as M31, are almost entirely undetectable in the HBM because of misdirected beaming. We analyze several refinements of the basic HBM: gamma-ray intensities that vary with angle from the beam axis; non-standard candle GRB luminosity functions; and models including a subset of bursters that do not escape from the Galaxy. We also discuss the energy budgets for the bursters, the origins of their recoils, and the physics of burst beaming and alignment. One possible physical model is based on the magnetar model of soft gamma repeaters (SGRs). Empirical bounds on the rate of formation and peculiar velocities of SGRs imply that there exist ~104 to ~107 aged SGRs in the Galactic halo within a distance ~100 kpc. The HBM gives an acceptable fit to observations only if it satisfies some special conditions (b ≈ 20°; uniform bursting rate) that are possible, but for which there are no clear and compelling theoretical justifications. The cosmological burst hypothesis is more generic and thus more attractive in this sense.
On the genealogy of asexual diploids.

Given molecular genetic data from diploid individuals that, at present, reproduce mostly or exclusively asexually without recombination, an important problem in evolutionary biology is detecting evidence of past sexual reproduction (i.e., meiosis and mating) and recombination (both meiotic and mitotic). However, currently there is a lack of computational tools for carrying out such a study. In this article, we formulate a new problem of reconstructing diploid genealogies under the assumption of no sexual reproduction or recombination, with the ultimate goal being to devise genealogy-based tools for testing deviation from these assumptions. We first consider the infinite-sites model of mutation and develop linear-time algorithms to test the existence of an asexual diploid genealogy compatible with the infinite-sites model of mutation, and to construct one if it exists. In this ideal case, our chance of detecting signatures of past sexual reproduction is maximized. Then, we relax the infinite-sites assumption and develop an integer linear programming formulation to reconstruct asexual diploid genealogies with the minimum number of homoplasy (back or recurrent mutation) events. If this number is substantially larger than that expected for typical asexual organisms, then it may suggest that sexual reproduction or recombination may have played an important role in the evolutionary history. We apply our algorithms on simulated data sets with sizes of biological interest.
Polarization observables in vector meson photoproduction

Abstract The photoproduction of vector mesons(ρ, ω, o) is of renewed interest because intense high energy beams of polarized electrons, photons and protons are under development. These beams and also polarized targets make it possible to explore the dynamics of basic baryon structure. As a step towards that goal, an analysis of all possible polarization observables for the case of vector meson photoproduction from a nucleon target is presented.
Quantum measures and the coevent interpretation

This paper first reviews quantum measure and integration theory. A new representation of the quantum integral is presented. This representation is illustrated by computing some quantum ( Lebesgue ) 2 integrals. The rest of the paper only considers finite spaces. Anhomomorphic logics are discussed and the classical domain of a coevent is studied. Pure quantum measures and coevents are considered and it is shown that pure quantum measures are strictly contained in the extremal elements for the set of quantum measures bounded above by one. Moreover, we prove that any quantum measure on a finite event space A can be transferred to an ordinary measure on an anhomomorphic logic A * In this way, the quantum dynamics on A can be described by a classical dynamics on the larger space A *
Highly stereoselective synthesis of 2,6-cis-substituted tetrahydropyrans using a one-pot sequential catalysis.

A catalytic highly diastereo- and enantioselective synthesis of 2,6-cis-substituted tetrahydropyrans was realized using a one-pot sequential catalysis involving Henry and oxa-Michael reactions. The nitroaldol products obtained in a highly enantioselective copper(II)-catalyzed Henry reaction between nitromethane and 7-oxo-hept-5-enals were subsequently treated with a catalytic amount of camphorsulfonic acid (CSA) to give the desired tetrahydropyran derivatives in excellent yields, diastereoselectivities (dr >99:1), and enantioselectivities (ee = 98–99%). The reaction can also be used for the high stereoselective synthesis of a cis-2,6-disubstituted morpholine.
Direct synthesis of thioethers from sulfonyl chlorides and activated alcohols

An efficient, safe one-pot synthesis of thioethers from aromatic sulfonyl chlorides and activated alcohols has been developed under non-aqueous conditions.
Changes in Heart Transplant Recipients That Parallel the Personalities of Their Donors

Study evaluating whether changes following heart transplant surgery parallel the history of the donors, based on the systemic memory hypothesis which predicts that all dynamical systems that contain recurrent feedback loops store information and energy to various degrees.
Social identity and attitudes toward foreign policy: evidence from a youth survey in Turkey

This paper focuses on the relationship between social identity based on national, religious, or international affiliations and attitudes toward foreign policy in the Turkish context. Evidence is drawn from an original survey conducted among university students in Turkey. The results show that students’ social identity has a significant correlation with their perceptions of foreign policy. Most Turkish university students provide conditional support for the new directions in Turkey’s foreign policy, but those with an Islamic identity appear to be more supportive of the Adalet ve Kalkonma Partisi’s (Justice and Development Party) policies. Most university students believe that Turkey’s future lies in the European Union and the Central Asian Turkic republics rather than in the Middle East. Overall, the perceptions of educated youth toward foreign policy are shaped by both social identity and their conceptions of national interest. Prime Minister Recep Tayyip Erdou was given a hero’s welcome in Turkey after he stormed out of a meeting during a heated debate with Israeli Prime Minister Shimon Peres at the Davos Economic forum in 2009. The event, known as the “one-minute crisis,” was a reflection of Turkey’s foreign policy activism in the new millennium. 1 This activism is usually attributed to the Adalet ve Kalkonma Partisi (AKP, the Justice and Development Party) and its chief foreign policy strategist Ahmet Davutou glu, who became Turkey’s foreign minister in 2009. The new activism in foreign policy is most visible in the government’s approach toward Middle Eastern countries. The Islamic credentials of the AKP leadership combined with the country’s increasing orientation toward this region have led some students of Turkish politics to talk of the “Middle Easternization” of foreign policy 2 or of a profound shift “enacting neo-Ottomanism,” 3 although others have argued that Turkey’s foreign policy continues to be oriented mainly toward the West. 4 One line of criticism of the AKP’s foreign policy builds on the argument that a trend of Islamization is taking place in Turkish society and that this is causing a shift from the West to the East in foreign
A Simple Method for Converting a Cost-Effectiveness Analysis into a Cost-Benefit Analysis with an Application to State Mental Health Expenditures

If cost-effectiveness and cost-benefit analyses are to produce identical rankings of programs, there is a simple equivalence between the criteria that enables one to derive a value for the effect that is being maximized. The value depends on knowing two magnitudes: (1) the cutoff cost-effectiveness ratio and (2) the marginal cost of public funds. The method is illustrated by trying to value state psychiatric hospital episodes using the revealed preference approach. Values varied by the state undertaking the expenditure (from a high of $52,526 in Pennsylvania to a low of $2,177 in Wisconsin) and the size of the predetermined federal budget assumed (a $1 billion budget produces a $10,418 value, and the actual budget of $7 billion produces a $54,540 value).
The Broken Ray Transform on the Square

We study a particular broken ray transform on the Euclidean unit square and establish injectivity and stability for $$C_{0}^{2}$$ perturbations of a vanishing absorption parameter $$\sigma \equiv 0$$ . Given an open subset $$E$$ of the boundary, we measure the attenuation of all broken rays starting and ending at $$E$$ with the standard optical reflection rule applied to $$\partial \Omega {\setminus } E$$ . Using the analytic microlocal approach of Frigyik et al. for the X-ray transform on generic families of curves, we show injectivity via a path unfolding argument under suitable conditions on the available broken rays. Then we show that with a suitable decomposition of the measurement operator via smooth cutoff functions, the associated normal operator is a classical pseudo differential operator of order $$-1$$ , which leads to the desired result.
Bowen's disease

J ohn T. Bowen 6rst described the entity bearing his name in 19 12.’ From that time, Bowen’s disease has been identified as squamous cell carcinoma in situ. Since Graham and Helwig iirst postulated a paraneoplastic nature of Bowen’s disease, several studies had initially confirmed this observation. More recently, carefully controlled studies have shown the disease lacks a paraneoplastic association.
Afraid of a ‘Kosovo Scenario’: A Disquieting Precedent for International Conflict Management

The UN Security Council Resolution 1244 (1999) represented an interim settlement that permitted conflict de-escalation while postponing the search for a lasting political solution. The final settlement should have been reached through negotiations between Belgrade and the Kosovo Albanians, and then endorsed by the UN Security Council, in accordance with the UN Resolution 1244 (1999). However, citing the ambiguity of the interim agreement and a deadlock in the negotiations, the United States and its allies recognized Kosovo's unilateral declaration of independence in February 2008, thereby allowing the Kosovo Albanians to defect from the peace process. Therefore, instead of an internationally endorsed negotiated outcome, there has been an attempt at a unilaterally enforced political settlement, in disregard for the authority of the UN Security Council, which had placed Kosovo under international administration. The subsequent involvement of the International Court of Justice has failed to resolve the conte...
Equilibrium with divergence of opinion

Abstract Since the less informed incorrectly estimate asset returns, they anticipate higher returns from their risky investments. They thus over-invest in risky securities. They are rewarded by higher total portfolio returns. Too high a proportion of less-informed investors lowers the return on risky assets. Equilibrium requires that the less informed's rate of return equal the informed's. The less informed control a stable equilibrium percentage of total wealth. Since an individual's recent investment experience correlates with his terminal wealth, learning need not reduce the less informed's risky asset exposure. Implications exist for the slope of the return versus systematic risk curve.
Transition metal fullerene chemistry: The route from structural studies of exohedral adducts to the formation of redox active films

Abstract This article encompasses: (1) an update on recent developments on transition metal/fullerene adduct formation, (2) the use of metal complexes to form ordered crystalline adducts of fullerenes for study by X-ray diffraction, (3) the characterization of fullerene oxides, and (4) the formation of redox active films from fullerene oxides and from fullerenes.
Ramification of local rings along valuations

In this paper we discuss stable forms of extensions of algebraic local rings along a valuation in all dimensions over a field k of characteristic zero, and generalize a formula of Ghezzi, Ha and Kashcheyeva describing the extension of associated graded rings along the valuation for stable extensions of regular algebraic local rings of dimension two to arbitrary ground fields k of characteristic zero. We discuss the failure of this result in positive characteristic. The main technique used in this paper is the algorithm for constructing generating sequences of Cutkosky and Vinh (2014) [6]. In Theorem 1.4, we show that the stable forms of extensions of regular algebraic local rings of dimension two over arbitrary ground fields of characteristic zero have a particularly simple relation between their generating sequences.
Long-lived Double-barred Galaxies: Critical Mass and Length Scales

A substantial fraction of disk galaxies is double-barred. We analyze the dynamical stability of such nested bar systems by means of Liapunov exponents, by fixing a generic model and varying the inner (secondary) bar mass. We show that there exists a critical mass below which the secondary bar cannot sustain its own orbital structure and above which it progressively destroys the outer (primary) bar-supporting orbits. In this critical state, a large fraction of the trajectories (regular and chaotic) is aligned with either bar, suggesting the plausibility of long-lived dynamical states when secondary-to-primary bar mass ratio is of the order of a few percent. Qualitatively similar results are obtained by varying the size of the secondary bar, within certain limits, while keeping its mass constant. In both cases, an important role appears to be played by chaotic trajectories that are trapped around (especially) the primary bar for long periods of time.
An environmentally benign synthesis of cis-2,6-disubstituted tetrahydropyrans via indium-mediated tandem allylation/Prins cyclization reaction.

In the presence of indium metal, 3-iodo-2-[(trimethylsilyl)methyl]propene (1) reacts with sequentially added aldehydes to provide cis-2,6-disubstituted tetrahydropyrans in good yields. Evidence suggests that InI, formed upon aldehyde (R1CHO) allylation in aqueous media, acts as a promoter for the silyl-Prins reaction with the second equivalent of added aldehyde (R2CHO). The preparation of cyclohexenyl-fused pyrans via this one-pot, three-component coupling process is presented, as is a short formal synthesis of (±)-centrolobine.
The So-Called Positive Photo-Electric Emission (Inverse Effect) and the Reality of the Sub-Electron

A few observers have reported the discharge of positive electricity produced by ultra-violet light. Dember found that a metal plate exposed to ultra-violet light in vacuum had the power to communicate a positive charge to a receiving cylinder when the proper accelerating field was applied. His experiments have recently been repeated by DuBridge, who reports that Dember’s results can be entirely accounted for on the basis of the photo-electric effect produced on the collecting cylinder by scattered ultra-violet light against which no precautions had been taken. His conclusions are "there is no measurable photo-electric production of either gaseous or metallic positive ions by the range of wave lengths emitted by the quartz mercury lamp. R. Bar and F. Luchsinger working with small particles of paraffin and selenium in a Millikan electron apparatus found that some of the particles showed the inverse effect, that is, they became charged negatively when illuminated by ultra-violet light. This has been construed by some workers as indicating the discharge of positive electricity. However, as these men were only using the ultra-violet light to charge up their particles in order to measure the charge communicated, and were not interested in the source of the photo-electric effect it is natural to assume that no special precautions were taken against the light striking the metallic plates of the condenser. The photo-electrons liberated from these metal surfaces being caught by the paraffin and selenium particles would make it seem as if the particles had lost a positive charge. S. Taubes, working in the same laboratory as Luchsinger and Bar and presumably with the same apparatus, reported this inverse effect when dealing with particles that had a large positive charge and showed that it is due to the photo-electrons given off by the condenser plates, for when these were coated with paraffin the inverse effect entirely disappeared. M. Hake, working at Vienna and using a diminutive Millikan electron apparatus designed by Professor Ehrenhaft, has recently reported results on nineteen different materials. He found that metals show both the inverse and the normal effect, depending on the gas in which the metal particles are suspended, and that some insulators, for example glycerine, always show the inverse effect in all gases. Wasser, working in the same laboratory as Hake gives results on mercury drops in N and CO2. He claims that drops of larger radius than 1.9 x 10-5 cm. always show the normal effect, that those between 1.1 and 1.9 x 10-5 cm. show both normal and the inverse effect, while those of smaller radius than 1.1 x 10-5 cm. always show the inverse effect. The following investigation was undertaken to test the correctness of the foregoing conclusions and to determine whether the changes in charge experienced by minute mercury droplets are of a magnitude corresponding to the electronic charge or to a charge smaller than this, as the Vienna physicists have maintained.
Multilinear interpolation between adjoint operators

Abstract Multilinear interpolation is a powerful tool used in obtaining strong-type boundedness for a variety of operators assuming only a finite set of restricted weak-type estimates. A typical situation occurs when one knows that a multilinear operator satisfies a weak Lq estimate for a single index q (which may be less than one) and that all the adjoints of the multilinear operator are of similar nature, and thus they also satisfy the same weak Lq estimate. Under this assumption, in this note we give a general multilinear interpolation theorem which allows one to obtain strong-type boundedness for the operator (and all of its adjoints) for a large set of exponents. The key point in the applications we discuss is that the interpolation theorem can handle the case q⩽1. When q>1, weak Lq has a predual, and such strong-type boundedness can be easily obtained by duality and multilinear interpolation (cf. Interpolation Spaces, An Introduction, Springer, New York, 1976; Math. Ann. 319 (2001) 151; in: Function Spaces and Applications (Lund, 1986), Lecture Notes in Mathematics, Vol. 1302, Springer, Berlin, New York, 1988; J. Amer. Math. Soc. 15 (2002) 469; Proc. Amer. Math. Soc. 21 (1969) 441).
Creating a university technology commercialisation programme: confronting conflicts between learning, discovery and commercialisation goals

Our knowledge-based society is pressing universities to transform from monastic scholarly enclaves into producers of new technologies and incubators of start-up firms. However, converting scientists’ curiosity-driven discoveries into commercially viable innovations has proven so difficult that observers liken the journey to crossing a ‘Valley of Death’. We conceptualise the challenges of commercialising university inventions in terms of three gaps: the technology discovery gap, the commercialisationgap, and the venturelaunchgap. We chronicle the inception and evolution of a technology commercialisation programme at the University of Oregon, relating how the university confronted and dealt with the three gaps, and describing the intra-organisational partnerships developed to address them. We find that negotiating the gaps requires assimilation of a technology commercialisation mission into the traditional academic missions of education and scientific discovery. To do this, universities must confront fundamental contradictions between learning, discovery, and commercialisation.
Evaluation of deep-space laser communication under different mission scenarios

A number of space agencies, including NASA, are considering free-space laser communications as a means for returning higher data-rates from future space missions. In this paper, potential deep-space missions are evaluated to show that with optical communication a 10× increase relative to state-of-the art telecommunication systems could be achieved. The maximum deep-space distance where ground transmitted laser beacons could assist acquisition and tracking; and operating points where optical communication performance degrades faster than the inverse square distance are also discussed.
Long Live Democracy: The Determinants of Political Instability in Latin America

Abstract We investigate the underlying causes of political instability in a panel of 18 Latin American countries from 1971–2000. We test whether regime type, regime durability, factionalism, income inequality, ethnic diversity, ethnic discrimination, regional spillover effects, urban growth and macroeconomic variables matter for instability. We find several important results: (1) democracy has a significant negative effect on instability that is robust to several alternative specifications; (2) factionalised political systems experience higher instability; (3) income inequality, ethnic fractionalisation, and urban growth have important nonlinear effects on instability; and (4) of the macroeconomic variables we study, only openness to trade has a significant negative effect on instability.
God and Natural Law: Reflections on Genesis 22

Genesis 22 is of interest for natural law doctrine because God’s command that Abraham sacrifice his son Isaac appears to be a divine violation of natural law. Various thinkers, including Immanuel Kant and John Thiel, have recognized the difficulty here. This essay focuses in particular on the approaches to this problem offered by Thomas Aquinas and Duns Scotus. For Scotus, Genesis 22 and similar biblical texts show that the Decalogue is changeable as regards the human-to-human laws. On this view, only the human-to-God laws are unchangeable. By detaching the human-to-human laws from the human-to-God laws, however, this position establishes the conditions for the autonomy of the human-to-human laws and undermines their status as real natural law. Thomas Aquinas’s approach is preferable: he argues that the natural law is unchangeable, but that as the lawgiver, God can accomplish its ends directly. This essay shows how developments in natural law doctrine are related to the interpretation of Scripture.
Sustainable water and energy in Gaza Strip

Abstract Shortage of fresh water is a common problem in different areas of the world including the Middle East. Desalination of seawater and brackish water is the cheapest way to obtain fresh water in many regions. This research focuses on the situation in Gaza Strip where there is a severe shortage in the energy and water supply. The depletion of fresh water supplies and lack of wastewater treatments result in environmental problems. A solar-powered co-generation plant producing water and energy is proposed to be a suitable solution for Gaza Strip. Solar energy, using concentrating solar thermal power (CSP) technologies, is used to produce electricity by a steam cycle power plant. Then the steam is directed to a desalination plant where it is used to heat the seawater to obtain freshwater. The main objective of this research is to outline a solution for the water problems in Gaza Strip, which includes a co-generation (power and water) solar-powered plant. The research includes four specific objectives: (1) an environmental and economic comparison between solar and fossil fuel energies, (2) technical details for the co-generation plant, (3) cost and funding, (4) the benefits.
Water-Soluble Organocatalysts for Hydrazone and Oxime Formation

The formation of oximes and hydrazones is widely used in chemistry and biology as a molecular conjugation strategy for achieving ligation, attachment, and bioconjugation. However, the relatively slow rate of reaction has hindered its utility. Here, we report that simple, commercially available anthranilic acids and aminobenzoic acids act as superior catalysts for hydrazone and oxime formation, speeding the reaction considerably over the traditional aniline-catalyzed reaction at neutral pH. This efficient nucleophilic catalysis, involving catalyst–imine intermediates, allows rapid hydrazone/oxime formation even with relatively low concentrations of the two reactants. The most efficient catalysts are found to be 5-methoxyanthranilic acid and 3,5-diaminobenzoic acid; we find that they can enhance rates by factors of as much as 1–2 orders of magnitude over the aniline-catalyzed reaction. Evidence based on a range of differently substituted arylamines suggests that the ortho-carboxylate group in the anthranila...
Hot Stars and Cool Clouds: The Photodissociation Region M16.

We present high-resolution spectroscopy and images of a photodissociation region (PDR) in M16 obtained during commissioning of the near-infrared spectrometer (NIRSPEC) on the Keck II telescope. PDRs play a significant role in regulating star formation, and M16 offers the opportunity to examine the physical processes of a PDR in detail. We simultaneously observe both the molecular and ionized phases of the PDR and resolve the spatial and kinematic differences between them. The most prominent regions of the PDR are viewed edge-on. Fluorescent emission from nearby stars is the primary excitation source, although collisions also preferentially populate the lowest vibrational levels of H2. Variations in density-sensitive emission-line ratios demonstrate that the molecular cloud is clumpy, with an average density n = 3 × 105 cm-3. We measure the kinetic temperature of the molecular region directly and find that T = 930 K. The observed density, temperature, and UV flux imply a photoelectric heating efficiency of 4%. In the ionized region, ni = 5 × 103 cm-3 and T = 9500 K. In the brightest regions of the PDR, the recombination line widths include a nonthermal component, which we attribute to viewing geometry.
Dusty Cometary Globules in W5

We report the discovery of four dusty cometary tails around low-mass stars in two young clusters belonging to the W5 star-forming region. Fits to the observed emission profiles from 24 μm observations with the Spitzer Space Telescope give tail lifetimes < 30 Myr, but more likely 5 Myr. This result suggests that the cometary phase is a short lived phenomenon, occurring after photoevaporation by a nearby O star has removed gas from the outer disk of a young low-mass star.
Computational dissection of Arabidopsis smRNAome leads to discovery of novel microRNAs and short interfering RNAs associated with transcription start sites

Abstract The profiling of small RNAs by high-throughput sequencing (smRNA-Seq) has revealed the complexity of the RNA world. Here, we describe a computational scheme for dissecting the plant smRNAome by integrating smRNA-Seq datasets in Arabidopsis thaliana. Our analytical approach first defines ab initio the genomic loci that produce smRNAs as basic units, then utilizes principal component analysis (PCA) to predict novel miRNAs. Secondary structure prediction of candidates' putative precursors discovered a group of long hairpin double-stranded RNAs (lh-dsRNAs) formed by inverted duplications of decayed coding genes. These gene remnants produce miRNA-like small RNAs which are predominantly 21- and 22-nt long, dependent of DCL1 but independent of RDR2 and DCL2/3/4, and associated with AGO1. Additionally, we found two classes of transcription start site associated (TSSa) RNAs located at sense (+) and antisense (−) approximately 100–200 bp downstream of TSSs, but are differentially incorporated into AGO1 and AGO4, respectively.
The role of the digital computer in mechanical translation of languages

The problem of applying digital computers to the mechanical translation of languages is currently receiving world-wide attention. Projects are under way at three or four major universities and research centers in the United States; others in England, Italy, and Russia. Of particular interest to military intelligence, the problem is emphasized by the increase in communication speed relating one language to another. It becomes more and more difficult to find experienced translators with the specialized knowledge in various fields of science and technology that is required for adequate translation and to provide an interchange of knowledge regarding the progress made in different areas of the world. The vast quantity of this material to be translated lends urgency to the development of some highspeed means of translation. An obvious means of satisfying this need lies in the application of high-speed digital and logical equipment. The solution of the mechanical translation problem by means of digital computers is one of continuing importance and extreme interest to those who would follow unique and interesting digital computer applications.
Catalytic metallonitrene/alkyne metathesis: a powerful cascade process for the synthesis of nitrogen-containing molecules.

A conceptually novel metallonitrene/alkyne metathesis cascade reaction has been developed for the construction of nitrogen-containing compounds from simple alkyne starting materials. Rhodium(II) tetracarboxylate salts are efficient catalysts for this reaction, in which an electrophilic rhodium nitrene is trapped by an alkyne, resulting in the formation of a new C–N bond and the generation of a reactive metallocarbene for cascade reaction. The reaction is tolerant of both alkyl and aryl substituents on the alkyne, and proceeds at room temperature in a variety of common solvents. The modular nature of the reaction allows for the rapid construction of congested bicyclic systems from remarkably simple alkyne starting materials.
A Variation-Aware Preferential Design Approach for Memory-Based Reconfigurable Computing

Static random access memory arrays designed in sub-90-nm technologies are highly vulnerable to process variation-induced read/write/access failures. In memory-based reconfigurable computing frameworks, which use large high-density memory array, such failures lead to incorrect execution of mapped applications. It causes loss in quality of service (QoS) for digital signal processing (DSP) applications. In this paper, we analyze the effect of parameter variations on QoS in a memory-based reconfigurable computing framework. Next, we propose a preferential design approach at both application mapping and circuit level, which can significantly improve QoS and yield under large parameter variations. The proposed application mapping process considers the reliability map of a memory array and maps the important components with respect to QoS to more reliable memory blocks under performance constraint. At circuit level, we exploit the read-dominant memory access pattern to skew the memory cells for better read stability leading to improved QoS. Such a architecture/circuit codesign approach can also tolerate increased failure rate at low operating voltage, thus facilitating low-power operation. The effect of the approach is studied for two common DSP applications, namely discrete cosine transform and finite-impulse response (FIR) filter. The simulation results for FIR application show 45% improvement in power at iso-QoS and 47% in yield for a target peak signal to noise ratio at 45-nm technology.
Land Quality and Prices

Although land values reflect land quality, the quality characteristics that determine values are only partly related to agricultural uses. The results of estimating a reduced-form equation explaining differences in land prices among states suggest that nearly two-thirds of this variation is attributed to nonagricultural uses. Therefore, a land quality index based on raw land prices will be biased, which in turn will result in biased coefficients in a production function or its dual. A cross-section land quality index which excludes the influence of nonagricultural uses is constructed. The main purpose of this paper is to construct a state-level, cross-section land quality index for land used in agricultural pursuits. The index is designed to adjust the land input for quality differences among states in aggregate agricultural production functions or short-run profit or cost functions where land is held constant. The weights employed to construct the index can also be used to construct a quality constant land price index for use in long-run agricultural profit or cost functions having land price as an argument.
Unraveling the secrets of Alzheimer's β-amyloid fibrils

Proteins adopt an amazing array of sequence-dependent structures that enable them to perform the many chemical functions critical to life. Over the past decade, however, it has become clear that many different protein sequences can also form misfolded, insoluble aggregates known as amyloid fibrils, with common structural elements. Amyloid fibrils appear to be involved in a number of diseases, including Alzheimer's disease, Parkinson's disease, Huntington's disease, prion diseases, and type II diabetes (1). Even ordinary globular proteins (e.g., myoglobin) can form amyloid fibrils under certain conditions (2), suggesting that fibril formation is a previously unappreciated general property of many proteins. Thus, it is of fundamental interest to understand how so many different protein sequences can adopt this alternative structure and it is of medical interest to understand and control disease-related amyloid formation. Knowledge of the three-dimensional structure of amyloid fibrils is critical for understanding the mechanism of fibrillogenesis and for design of possible inhibitors. Unfortunately, amyloid fibrils are noncrystalline and insoluble, and therefore are not amenable to x-ray crystallography and solution NMR, the classic tools of structural biology. In a recent issue of PNAS, Petkova et al. (3) report a structural model for Alzheimer's β-amyloid fibrils deduced primarily from solid-state NMR experiments. This work provides a significant step forward in understanding β-amyloid formation and showcases the power of solid-state NMR for obtaining structural information on important but challenging biomolecules.
Thermally induced vibrations of long thin- walled cylinders of open section.

Directional solar thermal field /sunlight/ effect on coupled nonplanar transverse and torsional vibrations of satellite cylindrical antennas in orbit
A compliant, underactuated hand for robust manipulation

This paper introduces the iRobot-Harvard-Yale (iHY) Hand, an underactuated hand driven by five actuators that is capable of performing a wide range of grasping and in-hand repositioning tasks. This hand was designed to address the need for a durable, inexpensive, moderately dexterous hand suitable for use on mobile robots. The primary focus of this paper will be on the novel simplified design of the iHY Hand, which was developed by choosing a set of target tasks around which the hand was optimized. Particular emphasis is placed on the development of underactuated fingers that are capable of both firm power grasps and low-stiffness fingertip grasps using only the compliant mechanics of the fingers. Experimental results demonstrate successful grasping of a wide range of target objects, the stability of fingertip grasping, and the ability to adjust the force exerted on grasped objects using high-impedance actuators and underactuated fingers.
Disturbed Rock Zone Geomechanics at the Waste Isolation Pilot Plant

The disturbed rock zone constitutes an important geomechanical element of the Waste Isolation Pilot Plant. The science and engineering underpinning the disturbed rock zone provide the basis for evaluating ongoing operational issues and their impact on performance assessment. Contemporary treatment of the disturbed rock zone applied to the evaluation of the panel closure system and to a new mining horizon improves the level of detail and quantitative elements associated with a damaged zone surrounding the repository openings. Technical advancement has been realized by virtue of ongoing experimental investigations and international collaboration. Initial sections summarize and document theoretical and experimental results, which quantify characteristics of the disturbed rock zone as applied to nuclear waste repositories in salt. This information is then applied to operational issues pertaining to recertification of the repository.
The role of stellar feedback in the formation of galaxies

Although supernova (SN) explosions and stellar winds happen at very small scales, they affect the interstellar medium (ISM) at galactic scales and regulate the formation of a whole galaxy. Previous attempts of mimicking these effects in simulations of galaxy formation use very simplified assumptions. We develop a much more realistic prescription for modeling the feedback, which minimizes any ad hoc subgrid physics. We start with developing high-resolution models of the ISM and formulate the conditions required for its realistic functionality: formation of multiphase medium with hot chimneys, superbubbles, cold molecular phase, and very slow consumption of gas. We find that this can be achieved only by doing what the real universe does: formation of dense (>10 H atoms cm–3), cold (T ≈ 100 K) molecular phase, where the star formation happens, and which young stars disrup. Another important ingredient is the effect of runaway stars: massive binary stars ejected from molecular clouds when one of the companions becomes an SN. Those stars can move to 10-100 pc away from molecular clouds before exploding themselves as SNe. This greatly facilitates the feedback. Once those effects are implemented into cosmological simulations, galaxy formation proceeds more realistically. For example, we do not have the overcooling problem. The angular momentum problem (resulting in a too massive bulge) is also reduced substantially: the rotation curves are nearly flat. The galaxy formation also becomes more violent. Just as often observed in quasar absorption lines, there are substantial outflows from forming and active galaxies. At high redshifts we routinely find gas with few hundred km s–1 and occasionally 1000-2000 km s–1. The gas has high metallicity, which may exceed the solar metallicity. The temperature of the gas in the outflows and in chimneys can be very high: T = 107-108 K. The density profile of dark matter is still consistent with a cuspy profile. The simulations reproduce this picture only if the resolution is very high: better than 50 pc, which is 10 times better than the typical resolution in previous cosmological simulations. Our simulations of galaxy formation reach the resolution of 35 pc.
Evaluation of monophosphoryl lipid A as an immune adjuvant for photodynamic therapy in a rat sarcoma model: preliminary results

Photodynamic therapy (PDT) is a treatment option for several forms of human cancer, and like traditional chemotherapy and ionizing radiation therapy, PDT alone is not curative for some cases. Recent efforts have aimed at developing strategies for adjuvant therapy for PDT. Given the nature of PDT-mediated cell damage, immunotherapy is a promising adjuvant for long-term control of solid tumors. A candidate immune stimulant for use with PDT is monophosphoryl lipid A (MLA), a non-toxic fraction of the endotoxin molecule. The hypothesis is that adjuvant MLA immunotherapy with PDT will improve local tumor control and prevent growth of subsequently implanted tumor cells when compared to PDT alone. To date, no significant differences in circulating leukocyte populations or tumor infiltrating lymphocyte populations have been identified in 9L tumor-bearing F344 rats after systemic administrations of MLA. Likewise, no significant difference has been identified in local tumor control following PDT of 9L tumors with or without adjuvant MLA. Further results are pending.
CHARLES CAMPBELL AT SIXTY-FIVE: A TRIBUTE TO INNOVATION AND ENDURING DEDICATION

A retrospective of the career of Charles E. Campbell in condensed matter physics is presented as a tribute to his pathbreaking contributions to quantum many-body theory and his selfless dedication to the advancement of the research community associated with the Condensed Matter Workshop series.
A bridgehead α-amino carbanion: facile preparation of C5(bridgehead)-substituted analogues of (±)-5H-dibenzo[a,d]cyclohepten-5,10-imine including a stable α-iodo secondary amine

Abstract The preparation of C5(bridgehead)-substituted analogues of (±)-5 H -dibenzo[a,d]cyclohepten-5,10-imine via α-lithiation of a tert -butylformamidine precursor is presented.
Legal Positivism in American Jurisprudence

Acknowlegments 1. Why study legal positivism 2. Positivism and formalism 3. The varieties of formalism 4. Legal process and the shadow of positivism 5. The false choice between the Warren Court and legal process 6. Fundamental rights and the problem of insatiability 7. New legal positivism and the incorporation of morality.
Helmet effectiveness in preventing motorcycle driver and passenger fatalities

Helmet effectiveness in preventing fatalities to motorcycle drivers and passengers was determined by applying the double pair comparison method to the Fatal Accident Reporting System (FARS) data for 1975 through 1986. Motorcycles with a driver and a passenger, at least one of whom was killed, were used. In order to reduce as much as possible potentially confounding effects due to the dependence of survivability on sex and age, the analysis is confined to male drivers (there were insufficient female driver data), and to cases in which the driver and passenger age do not differ by more than three years. Motorcycle helmet effectiveness estimates are found to be relatively unaffected by performing the analyses in a number of ways different from that indicated above. It was found that helmets are (28 +/- 8)% effective in preventing fatalities to motorcycle riders (the error is one standard error), the effectiveness being similar for male and female passengers, and similar for drivers and passengers. An additional result found was that the fatality risk in the driver seat exceeds that in the passenger seat by (26 +/- 2)%. The 28% effectiveness found generates calculated fatality increases from repeal of mandatory helmet-wearing laws that are compatible with observed increases.
Partial oxidation of methane to formaldehyde by means of molecular oxygen

Abstract The partial oxidation of methane to formaldehyde by molecular oxygen has been studied, with molybdenum(VI) oxide-silica and related catalysts. Although HCHO selectivities in excess of 85% could be obtained at very low conversions, sodium contamination as low as 300 ppm Na was found to lower both activity and selectivity to formaldehyde. On Na-free MoO3SiO2 catalysts, methane was shown to be oxidized, in parallel, to HCHO and CO2 via a common activation step. CO was produced via HCHO, and became the dominant oxidation product at high conversions. Methanol was detected in trace quantities, and is presumed to be an intermediate in formaldehyde formation. Reagent MoO3, and MoO3 in excess of ~0.1 monolayers on silica did not catalyze the oxidation of methane significantly. Molybdenum(VI) oxide appears to promote the catalytic activity already present on the bare silica.
Hydraulic Programs for Maximum Hydraulic Horsepower and Impact Force on the Rock Surface of the Hole Bottom in Jet Drilling

In this paper, empirical formulations have been developed to calculate, from full-scale experimental results, the hydraulic horsepower and impact force at the rock surface. Two new hydraulic programs were established to optimize bit hydraulics on the rock surface of the hole bottom. The new theory and methods, when tested in oilfield drilling practice, have increased rate of penetration (ROP) and reduced drilling cost.
Light induced halogenative decarboxylation of thiohydroxamic esters

Abstract The generality of light initiated halogenative decarboxylation of thiohydroxamic esters was studied. This method gave high yields of alkyl chlorides, bromides and iodides derived from primary, secondary and tertiairy substituted carboxylic acids.
The Influence of Secondary Convection on Axial Segregation in a Floating Zone

The redistribution of impurity due to secondary convection in a cylindrical floating zone is studied using a control volume-based numerical technique. The flow is induced by differential rotation of the feed rod and crystal. Attention is focused on the transient stage of segregation. It is found that the transient length increases with the strength of secondary convection. A maximum in radial segregation is found to occur when secondary convection creates radial gradients but is not strong enough to homogenize them. The influence of cellular structure on the transient length is also examined.