cssi/SciSciGPT-SciSciNet huggingface dataset:
QUANTUM CONDUCTANCE AND ELECTRONIC PROPERTIES OF LOWER DIAMONDOID MOLECULES AND DERIVATIVES

Diamondoids and their derivatives have found major applications as templates and as molecular building blocks in nanotechnology. An ab initio method we calculated the quantum conductance and the essential electronic properties of two lower diamondoids (adamantane and diamantane) and three of their important derivatives (amantadine, memantine and rimantadine). We also studies two artificial molecules that are built by substituting one hydrogen ion with one sodium ion in both adamantane and diamantane molecules. Most of our results are based on an infinite Au two-probe system constructed by ATK and VNL software, which comprise TRANSTA-C package. By changing various system structures and molecule orientations in linear Au and 2 × 2Au probe systems, we found that although the conductance of adamantane and diamantane are very small, the derivatives of the lower diamondoids have considerable conductance at specific orientations and also showed interesting electronic properties. The quantum conductance of such molecules will change significantly by changing the orientations of the molecules, which approves that residues like nitrogen and sodium atoms have great effects on the conductance and electronic properties of single molecule. There are obvious peaks near Fermi energy in the transmission spectrums of artificial molecules, indicating the plateaus in I–V characteristics of such molecules.
Change Their Choice! Changing Behavior Using the CAN Approach and Activism Research

Most of our research on eating behavior has no impact on health or public policy. Part is due to the nontranslational way we often conduct our studies; part is due to us not having a useful framework that organizes our conclusions. This paper's first purpose is to offer an organizing framework that shows how nearly all effective interventions on food choice either make healthy choices more convenient (physically or cognitively), more attractive (comparatively or absolutely), or more normal (perceived or actual). This paper's second purpose is to introduce the notion of activism research—an approach to designing and executing studies in a way that makes consumer psychology research more actionable, useful, effective, and scalable. Together these two tools could help expand both the relevance and reach, and impact of what we do.
TRANSVERSE MOMENTUM DISTRIBUTIONS FROM EFFECTIVE FIELD THEORY

We present a factorization theorem for the low transverse momentum (pT) and rapidity (Y) distribution of the Higgs and electroweak gauge bosons using the Soft-Collinear Effective Theory. In the region M ≫ pT ≫ ΛQCD, where M denotes the mass of the electroweak object, the factorization formula is given in terms of perturbatively calculable functions and the standard PDFs. For pT ~ ΛQCD, the factorization theorem is given in terms of non-perturbative Impact-parameter Beam Functions (iBFs) and an Inverse Soft Function (iSF). The iBFs correspond to completely unintegrated PDFs and can be interesting probes of momentum distributions in the nucleon. The iBFs and the iSF are grouped together and written as a product of a gauge invariant and non-perturbative Transverse Momentum Function (TMF) with the standard PDFs. We present results of NLL resummation for the Higgs and Z-boson distributions and give a comparison with Tevatron data.
Polarimetric MIMO Radar With Distributed Antennas for Target Detection

Multiple-input-multiple-output (MIMO) radar systems with widely separated antennas enable viewing the target from different angles, thereby providing spatial diversity gain. Polarimetric design of the transmit waveforms based on the properties of the target scattering matrix provides better performance than transmitting waveforms with only fixed horizontal or vertical polarizations. We propose a radar system that combines the advantages of both systems by transmitting polarized waveforms from multiple distributed antennas, in order to detect a point-like stationary target. The proposed system employs 2-D vector sensors at the receivers, each of which measures the horizontal and vertical components of the received electric field separately. We design the Neyman-Pearson detector for such systems. We derive approximate expressions for the probability of false alarm (PFA) and the probability of detection (PD). Using numerical simulations, we demonstrate that optimal design of the antenna polarizations provides improved performance over MIMO systems that transmit waveforms of fixed polarizations over all the antennas. We also demonstrate that having multiple widely separated antennas gives improved performance over single-input-single-output (SISO) polarimetric radar. We also demonstrate that processing the vector measurements at each receiver separately gives improved performance over systems that linearly combine both the received signals to give scalar measurements.
Antropología y Desarrollo

Arturo Escobar nacio y crecio en Colombia. Se educo en la Universidad del Valle (Cali, Colombia), en la Cornell University y en la Universidad de California, en Berkeley (donde se doctoro en 1987). Entre sus especialidades figuran la ecologia politica y la antropologia del desarrollo, los movimientos sociales y las nuevas tecnologias. Es autor de Encountering Development: the Making and Unmaking of the Third World (1995). Actualmente es Catedratico Adjunto de Antropologia de la Universidad de Massachusetts, en Amherst, MA 01003, USA., email: aescobar@anthro.umass.edu .
Active Property Testing

One motivation for property testing of boolean functions is the idea that testing can provide a fast preprocessing step before learning. However, in most machine learning applications, it is not possible to request for labels of arbitrary examples constructed by an algorithm. Instead, the dominant query paradigm in applied machine learning, called *active learning*, is one where the algorithm may query for labels, but only on points in a given (polynomial-sized) unlabeled sample, drawn from some underlying distribution D. In this work, we bring this well-studied model to the domain of testing. We develop both general results for this *active testing* model as well as efficient testing algorithms for several important properties for learning, demonstrating that testing can still yield substantial benefits in this restricted setting. For example, we show that testing unions of d intervals can be done with O(1) label requests in our setting, whereas it is known to require Omega(d) labeled examples for learning (and Omega(sqrt{d}) for passive testing [KR00] where the algorithm must pay for every example drawn from D). In fact, our results for testing unions of intervals also yield improvements on prior work in both the classic query model (where any point in the domain can be queried) and the passive testing model as well. For the problem of testing linear separators in R^n over the Gaussian distribution, we show that both active and passive testing can be done with O(sqrt{n}) queries, substantially less than the Omega(n) needed for learning, with near-matching lower bounds. We also present a general combination result in this model for building testable properties out of others, which we then use to provide testers for a number of assumptions used in semi-supervised learning. In addition to the above results, we also develop a general notion of the *testing dimension* of a given property with respect to a given distribution, that we show characterizes (up to constant factors) the intrinsic number of label requests needed to test that property. We develop such notions for both the active and passive testing models. We then use these dimensions to prove a number of lower bounds, including for linear separators and the class of dictator functions.
Commodity bundling in the supply chain: a simulation study

Commodity bundling has received little attention in the supply chain literature although products in a bundle are delivered through supply chains. Marketing and economics literature largely discuss the issue from pricing and consumer behaviour perspectives. In this study, we investigate bundling strategy from a supply chain and operations standpoint. Our results indicate that not only the products in the bundle but also the supply chains providing these products should be matched considering capacity limitations and volume flexibilities. We discuss theoretical implications of our results and provide recommendations for practicing managers based on our findings and insights.
The Endoscopic Diagnosis and Possible Treatment of Nerve Root Avulsions in the Management of Brachial Plexus Injuries

The spinal cord, dorsal rootlets, and ventral rootlets at the cervical level were visualized by endoscopy in ten goats. It is currently possible to visualize and document avulsed rootlets. With refinement in techniques and instruments, it will be possible to perform repairs, transfers or implantation of avulsed rootlets in the brachial plexus.
Conjunctive Query Answering over an f-ALC Knowledge Base

In this paper, we present the very first algorithm for answering expressive fuzzy conjunctive queries, which allow the occurrence of both lower bound and the upper bound of threshold in a query atom, over the relative expressive fuzzy DL, f-ALC. The algorithm we suggest here can easily be adapted to existing (and future) DL implementations. We distinguish the queries into two categories, the ground and the variable-involved Boolean queries, and present the algorithms for them sequentially.
The corridor problem: Preliminary results on the no-toll equilibrium

Consider a traffic corridor that connects a continuum of residential locations to a point central business district, and that is subject to flow congestion. The population density function along the corridor is exogenous, and except for location vehicles are identical. All vehicles travel along the corridor from home to work in the morning rush hour, and have the same work start-time but may arrive early. The two components of costs are travel time costs and schedule delay (time early) costs. Determining equilibrium and optimum traffic flow patterns for this continuous model, and possible extensions, is termed "The Corridor Problem". Equilibria must satisfy the trip-timing condition, that at each location no vehicle can experience a lower trip price by departing at a different time. This paper investigates the no-toll equilibrium of the basic Corridor Problem.
Population III.1 stars: formation, feedback and evolution of the IMF

I discuss current theoretical expectations of how primordial, Pop III.1 stars form. Lack of direct observational constraints makes this a challenging task. In particular predicting the mass of these stars requires solving a series of problems, which all affect, perhaps drastically, the final outcome. While there is general agreement on the initial conditions, H_2-cooled gas at the center of dark matter minihalos, the subsequent evolution is more uncertain. In particular, I describe the potential effects of dark matter annihilation heating, fragmentation within the minihalo, magnetic field amplification, and protostellar ionizing feedback. After these considerations, one expects that the first stars are massive >~100Msun, with dark matter annihilation heating having the potential to raise this scale by large factors. Higher accretion rates in later-forming minihalos may cause the Pop III.1 initial mass function to evolve to higher masses.
Wave-particle duality in general relativity

In this paper a one-to-one correspondence is established between space-time metrics of general relativity and the wave equations of quantum mechanics. This is done by first taking the square root of the metric associated with a space and from there, passing directly to a corresponding expression in the dual space. It is shown that in the case of a massless particle, Maxwell’s equation for a photon follows while in the case of a particle with mass, Dirac’s equation results as a first approximation. Moreover, this one-to-one correspondence suggests a natural explanation of wave-particle duality. As a consequence, the distinction between quantum mechanics and classical relativistic mechanics is more clearly understood and the key role of initial conditions is emphasized.
L1 data cache decomposition for energy efficiency

The L1 data cache is a time-critical module and, at the same time a major consumer of energy. To reduce its energy-delay product, we apply two principles of low-power design: specialize part of the cache structure and break the cache down into smaller caches. To this end, we propose a new L1 data cache structure that combines a Specialized Stack Cache (SSC) and a Pseudo Set-Associative Cache (PSAC). Individually, our SSC and PSAC designs have a lower energy-delay product than previously-proposed related designs. In addition, their combined operation is very effective. Relative to a conventional 2-way 32 KB data cache, a design containing a 4-way 32 KB PSAC and a 512 B SSC reduces the energy-delay product of several applications by an average of 44%.
Eliminating the Audit Expectations Gap: Reality or Myth?

The audit expectations gap is of serious concern to the UK accounting profession with the Department of Trade and Industry proposing a new framework for independent regulation of the accounting profession. However the new Accounting Foundation has had its role placed under review following the Enron collapse and introduction of the Sarbanes-Oxley Act 2002. This resulted in responsibility for independent regulation of the accounting profession being transferred to the reconstituted Financial Reporting Council. High profile failure of financial services firms, commencing with the secondary banking crisis in the 1970s, followed by collapses of banks such as Johnson Matthey Bankers (JMB), Bank of Credit and Commerce International (BCCI) and Barings, building societies such as Grays and insurers such as the recent problems at Equitable Life and Independent Insurance have given rise to further debate on the audit expectations gap. The debate surrounding the "expectations gap" often revolves around whether such a gap can be eliminated. Sikka, Puxty, Cooper and Wilmott argue that within a social context, the expectations gap will be difficult to eliminate due to social conflict and the fact that the meaning of social practices is always subject to challenges. It will however, be argued that even though the whole component definition of an audit may be subject to changes and challenges and therefore cannot be objective, elements within the definition of an audit and in particular, the fraud and error detection role of an audit can be relatively objective. (Paper presented at the 2007 Global Conference on Business and Finance)
Pulse-Phase Spectroscopy of SMC X-1 with Chandra and XMM-Newton: Reprocessing by a Precessing Disk?

We present pulse-phase X-ray spectroscopy of the high-mass X-ray pulsar SMC X-1 from five different epochs, using Chandra X-Ray Observatory ACIS-S and XMM-Newton EPIC pn data. The X-ray spectrum consistently shows two distinct components, a hard power law and a soft blackbody with kTBB ~ 0.18 keV. For all five epochs the hard component shows a simple double-peaked pulse shape and also a variation in the power-law slope, which becomes harder at maximum flux and softer at minimum flux. For the soft component, the pulse profile changes between epochs in both shape and phase relative to the power-law pulses. The soft component is likely produced by reprocessing of the hard X-ray pulsar beam by the inner accretion disk. We use a model of a twisted inner disk, illuminated by the rotating X-ray pulsar beam, to simulate pulsations in the soft component due to this reprocessing. We find that for some disk and beam geometries, precession of an illuminated accretion disk can roughly reproduce the observed long-term changes in the soft-pulse profiles.
Triggering and the pathophysiology of acute coronary syndromes

Insight into the pathophysiology of acute coronary syndromes can be gained by studying the role of triggering activities, such as heavy physical exertion and episodes of anger, in promoting plaque rupture and thrombosis, and the determinants of plaque vulnerability to disruption, which include lipid-rich plaque, a thin fibrous cap, and increased macrophage activity. This article focuses on the contribution of triggering activities and the potential mechanisms by which they may lead to acute myocardial infarction and sudden cardiac death.
Using the Schwinger Variational Functional for the Solution of Inverse Transport Problems

A new iterative inverse method for gamma-ray transport problems is presented. The method, based on a novel application of the Schwinger variational functional, is developed as a perturbation problem in which the current model (in the iterative process) is considered the initial, unperturbed system, and the actual model is considered the perturbed system. The new method requires the solution of a set of uncoupled one-group forward and adjoint transport equations in each iteration. Four inverse problems are considered: determination of (a) interface locations in a multilayer source/shield system, (b) the isotopic composition of an unknown source (including inert elements), (c) interface locations and the source composition simultaneously, and (d) the composition of an unknown layer in the shield. Only the first two problems were actually solved in numerical one-dimensional (spherical) test cases. The method worked well for the unknown interface location problem and extremely well for the unknown source composition problem. Convergence of the method was heavily dependent on the initial guess.
Combined Pd/C and Montmorillonite Catalysis for One-Pot Synthesis of Benzimidazoles

A series of nineteen benzimidazoles are prepared from ortho-nitroanilines via one-pot transfer hydrogenation, condensation, and dehydrogenation enabled by the concurrent use of two heterogeneous catalysts: montmorillonite-K10 and Pd/C. This strategy is further employed to accomplish a five-step, three-component synthesis of an antifungal benzimidazoquinazoline using a simple one-pot procedure.
The standardized-taper root canal preparation--Part 2. GT file selection and safe handpiece-driven file use.

Buchanan LS. The standardized-taper root canal preparation - Part 2. GT file selection and safe handpiece-driven file use. International Endodontic Journal , 34 , 63-71, 2001. Aim To present guidelines on GT file selection, and safe operation. Summary It is not necessary to remove excessive dentine for effective root canal preparation. GT files allow safe, standardized preparation, and should be selected to fit the case in hand. Small Root canals should be prepared with 0.06 and 0.08 taper GT files, whilst Large Root canals should be prepared with 0.10 GT or 0.12 Accessory GT files. The greatest challenge is un-learning habits acquired from traditional instrumentation methods. GT files should be used with light touch, and without up-down pumping motions. Spin speeds should be controlled below 300 r.p.m. for routine preparation. GT files are subject to fatigue and should be tracked to avoid overuse. It is recommended that GT files are discarded after the equivalent of five root canal preparations. For severe curvatures, GT files should be single-case tools. Key learning points • The standard GT file set comprises three instruments of 0.06, 0.08 and 0.10 taper. All are size 20 at the tip, and have a maximum diameter of 1 mm. • Accessory GT files have a standard taper 0.12, and maximum diameter of 1.5 mm. They are available in tip sizes 35, 50 and 70. • Large Roots are lower canines, upper anteriors, upper and lower single-rooted premolars, palatal roots of upper molars and distal roots of lower molars. They should be pre- pared with 0.10 GT or 0.12 Accessory GT files. • Small Roots are lower incisors, multirooted premolars, buccal roots of upper molars and mesial roots of lower molars. They should be prepared with 0.06 or 0.08 GT files. • All GT files should be used with light force and at the correct spin speed. • GT files should be discarded after the equivalent of five root canal uses.
Interferometry with a photon-number resolving detector

With photon-number resolving detectors, we show compression of interference fringes with increasing photon numbers for both Michelson and Fabry-Perot interferometers. We also theoretically show supersensitivity for nonclassical light.
Finance, Organization, and Impacts of U.S. Agricultural Research: Future Prospects

The objective of this paper is to review key conceptual issues in the finance, management, and economic impact analysis of agricultural research of the U.S. and other western developed countries, to critique evidence on the impacts of R&D, to summarize new developments and emerging trends in agricultural science policy, and to speculate about the likely effect of these trends during the 21st century on impacts of R&D. The conceptual review will emphasize refinements in the theory of public goods associated with a class of impure public goods. Some overall conclusions will be presented for U.S. agricultural research policy of the 21st century.
Cytoplasmic Envelopment of Human Cytomegalovirus Requires the Postlocalization Function of Tegument Protein pp28 within the Assembly Compartment

The assembly of herpesvirus remains incompletely defined due to the structural complexity of these viruses. Although the assembly of the capsid of these large DNA viruses is well studied and reasonably well conserved for all members of this diverse family of viruses, the cytoplasmic processes of tegumentation and envelopment are not well understood. The virion of the largest human herpesvirus, human cytomegalovirus (HCMV), contains over 70 virus-encoded proteins that are incorporated during a nuclear and cytoplasmic phase of assembly. Envelopment of this virus requires the function of at least one tegument protein, pp28, the product of the UL99 open reading frame. However, the role of pp28 in the envelopment of HCMV remains undefined. We have generated a pp28 mutant virus that encodes only the first 50 amino acids (aa) of this 190-aa virion protein. This virus is replication impaired and is defective in virus assembly. Characterization of both intracellular and extracellular virions from cells infected with this viral mutant indicated that the decrease in production of infectious virus was secondary to a defect in envelopment and the accumulation of tegumented, noninfectious intracellular particles. Image analysis using fluorescence recovery after photobleaching indicated that the pp28 mutant protein encoded by this virus failed to efficiently accumulate in the virus assembly compartment (AC). Our results suggest that pp28 must accumulate in the AC for efficient envelopment of the particle and provide evidence for a direct role of this tegument protein in the late stages of assembly, such as envelopment.
Detailed modeling and analysis of spacecraft plume/ionosphere interactions in low Earth orbit

Detailed direct simulation Monte Carlo/particle-in-cell simulations involving the interaction of spacecraft thruster plumes with the rarefied ambient ionosphere are presented for steady thruster firings in low Earth orbit (LEO). A nominal mass flow rate is used to prescribe the rocket exit conditions of a neutral propellant species for use in the simulations. The charge exchange interactions of the steady plume with the rarefied ionosphere are modeled using a direct simulation Monte Carlo/particle-in-cell methodology, allowing for a detailed assessment of nonequilibrium collisional and plasma-related phenomena relevant for these conditions. Results are presented for both ram- and wake-flow configurations, in which the thrusters are firing into (ram) or in the direction of (wake) the free stream ionosphere flow in LEO. The influence of the Earth's magnetic field on the development of the ion plume is also examined for three different field strengths: two limiting cases in which B→0 and B→∞, and the LEO case in which B=0.5 Gs. The magnetic field is found to have a substantial impact on the resulting neutral and ion plumes, and the gyroscopic motion of the magnetized ions results in a broadening of the ion energy distribution functions. The magnetic field model also incorporates a cross-field diffusion mechanism which is shown to increase the current density sampled far from the thruster.
Infections in Pediatric Transplant Recipients: Not Just Small Adults

Transplantation increasingly is being used as treatment for children with end-stage organ diseases, hematopoietic rescue from therapy used to treat malignancies, and as cure for primary immune deficiencies. This article reviews some of the major concepts regarding infections that complicate pediatric transplantation, highlighting differences in epidemiology, evaluation, treatment and prevention for children compared with adult recipients.
Information and the change in the paradigm in economics

The research for which George Akerlof, Mike Spence, and I are being recognized is part of a larger research program which, today, embraces hundred, perhaps thousands, of researchers around the worl...
Social Sector Expenditures and Rainy-Day Funds

Gonzalez and Paqueo examine the effects of budget stabilization funds--often called rainy-day funds--on the volatility of social spending and, for contrast, on nonsocial sector spending. They analyze the rainy-day funds of U.S. states. The authors find that rainy-day funds are ineffective in reducing the volatility of nonsocial sector expenditures but are effective in reducing the volatility of social sector expenditures. The authors also find that states that have stringent deposit and withdrawal rules have higher rainy-day fund balances, and thus are more effective in reducing the volatility of social sector expenditures. Finally, for long-term effectiveness, stabilization funds depend obviously on sustained economic growth.
Post bridge phenomena in electrical contacts at the initial stage

Consecutive stages of contact opening are described by the mathematical model. It includes, phenomena in separating contacts before there is melting, as well as appearance, evolution, and rupture of the liquid metal bridge, the arc ignition and spreading in the bridge metallic vapors until the transformation of the metallic arc phase into a gaseous one. The calculation of life, time, and energy of each stage, contact voltage, temperature, and other extent will compare with experimental data obtained by Takagi and Hang. It is shown, that arc duration depends on opening velocity, contact scale roughness, energy, and length of liquid bridge.
Supersymmetric defect models and mirror symmetry

We study supersymmetric field theories in three space-time dimensions doped by various configurations of electric charges or magnetic fluxes. These are supersymmetric avatars of impurity models. In the presence of additional sources such configurations are shown to preserve half of the supersymmetries. Mirror symmetry relates the two sets of configurations. We discuss the implications for impurity models in 3d $ \mathcal{N} $ = 4 QED with a single charged hypermultiplet (and its mirror, the theory of a free hypermultiplet) as well as 3d $ \mathcal{N} $ = 2 QED with one flavor and its dual, a supersymmetric Wilson-Fisher fixed point. Mirror symmetry allows us to find backreacted solutions for arbitrary arrays of defects in the IR limit of $ \mathcal{N} $ = 4 QED. Our analysis, complemented with appropriate string theory brane constructions, sheds light on various aspects of mirror symmetry, the map between particles and vortices and the emergence of ground state entropy in QED at finite density.
Recent advances on simulation and theory of hydrogen storage in metal–organic frameworks and covalent organic frameworks

This critical review covers the application of computer simulations, including quantum calculations (ab initio and DFT), grand canonical Monte-Carlo simulations, and molecular dynamics simulations, to the burgeoning area of the hydrogen storage by metal–organic frameworks and covalent-organic frameworks. This review begins with an overview of the theoretical methods obtained from previous studies. Then strategies for the improvement of hydrogen storage in the porous materials are discussed in detail. The strategies include appropriate pore size, impregnation, catenation, open metal sites in metal oxide parts and within organic linker parts, doping of alkali elements onto organic linkers, substitution of metal oxide with lighter metals, functionalized organic linkers, and hydrogen spillover (186 references).
Principles for Managing Technological Product Obsolescence

Products evolve to accommodate competitive market pressures, rapid rates of technology change, and constant improvements in performance and functionality. While adding functionality and value, the fast moving technologies also make products obsolete quickly. One of the primary reasons for product obsolescence is technological obsolescence which results when consumers are attracted to functions in newer models of products that are more technologically advanced. One way to deal with problem is ldquopiggybacking,rdquo a strategy that enables renewed functionality of a technologically obsolete product through the integration or add-on of a secondary device or component. Not to be confused with upgrading strategies, piggybacking requires a device that fits adjacent to, upon, or within the existing product architecture. Piggybacking is an attractive strategy for consumer electronic products that are particularly prone to technological obsolescence as it offers a means to accommodate fast and slower changing technologies within a single product. Currently, piggyback products are realized with ad hoc methods that rely on the experience and intuition of the designer, often applied inconsistently and not well known by less experienced designers. In this paper, a set of formal principles is presented for guiding the design of piggyback products. These principles are derived from the results of an empirical study of 72 different products. As part of the study, various products are analyzed with a dissection tool with representative principles derived from the data. The utility of these principles is demonstrated via the conceptual design of a novel piggyback products.
Overlapping Pools for High Throughput Targeted Resequencing

Resequencing genomic DNA from pools of individuals is an effective strategy to detect new variants in targeted regions and compare them between cases and controls. There are numerous ways to assign individuals to the pools on which they are to be sequenced. The naive, disjoint pooling scheme (many individuals to one pool) in predominant use today, offers insight into allele frequencies, but does not offer the identity of an allele carrier. We present a framework for overlapping pool design, where each individual sample is resequenced in several pools (many individuals to many pools). Upon discovering a variant, the set of pools where this variant is observed reveals the identity of its carrier. We formalize the mathematical framework for such pool designs, and list the requirements from such designs. Next, we build on the theory of error-correcting codes to design arrangements that overcome pitfalls of pooled sequencing. Specifically, three practical concerns of low coverage sequencing are investigated: (1) False positives due to errors introduced during amplification and sequencing; (2) False negatives due to undersampling particular alleles aggravated by non-uniform coverage; and consequently (3) Ambiguous identification of individual carriers in the presence of errors. We show that in practical parameters of resequencing studies, our designs guarantee high probability of unambiguous singleton carrier identification, while maintaining the features of naive pools in terms of sensitivity, specificity, and the ability to estimate allele frequencies. We demonstrate the ability of our designs by extracting rare variations on pooled short read data of 12 individuals from the 1000 Genome Pilot 3 project.
Condensation temperature trends among stars with planets

Results from detailed spectroscopic analyses of stars hosting massive planets are employed to search for trends between abundances and condensation temperatures. The elements C, S, Na, Mg, Al, Ca, Sc, Ti, V, Cr, Mn, Fe, Ni and Zn are included in the analysis of 64 stars with planets and 33 comparison stars. No significant trends are evident in the data. This null result suggests that accretion of rocky material on to the photospheres of stars with planets is not the primary explanation for their high metallicities. However, the differences between the solar photospheric and meteoritic abundances do display a weak but significant trend with condensation temperature. This suggests that the metallicity of the Sun's envelope has been enriched relative to its interior by about 0.07 dex.
SurveyMan: programming and automatically debugging surveys

Surveys can be viewed as programs, complete with logic, control flow, and bugs. Word choice or the order in which questions are asked can unintentionally bias responses. Vague, confusing, or intrusive questions can cause respondents to abandon a survey. Surveys can also have runtime errors: inattentive respondents can taint results. This effect is especially problematic when deploying surveys in uncontrolled settings, such as on the web or via crowdsourcing platforms. Because the results of surveys drive business decisions and inform scientific conclusions, it is crucial to make sure they are correct. We present SurveyMan, a system for designing, deploying, and automatically debugging surveys. Survey authors write their surveys in a lightweight domain-specific language aimed at end users. SurveyMan statically analyzes the survey to provide feedback to survey authors before deployment. It then compiles the survey into JavaScript and deploys it either to the web or a crowdsourcing platform. SurveyMan's dynamic analyses automatically find survey bugs, and control for the quality of responses. We evaluate SurveyMan's algorithms analytically and empirically, demonstrating its effectiveness with case studies of social science surveys conducted via Amazon's Mechanical Turk.
Complete intersection dimensions and Foxby classes

Abstract Let R be a local ring and M a finitely generated R -module. The complete intersection dimension of M –defined by Avramov, Gasharov and Peeva, and denoted CI - dim R ( M ) –is a homological invariant whose finiteness implies that M is similar to a module over a complete intersection. It is related to the classical projective dimension and to Auslander and Bridger’s Gorenstein dimension by the inequalities G - dim R ( N ) ⩽ CI - dim R ( N ) ⩽ pd R ( N ) . Using Blanco and Majadas’ version of complete intersection dimension for local ring homomorphisms, we prove the following generalization of a theorem of Avramov and Foxby: Given local ring homomorphisms φ : R → S and ψ : S → T such that φ has finite Gorenstein dimension, if ψ has finite complete intersection dimension, then the composition ψ ∘ φ has finite Gorenstein dimension. This follows from our result stating that, if M has finite complete intersection dimension, then M is C -reflexive and is in the Auslander class A C ( R ) for each semidualizing R -complex C .
Gravitomagnetism in superconductors and compact stars

There are three experimentally observed effects in rotating superconductors that are so far unexplained. Some authors have tried to interpret such phenomena as possible new gravitational properties of coherent quantum systems. In particular, they suggest that the gravitomagnetic field of that kind of matter may be many orders of magnitude stronger than the one expected in the standard theory. Here I show that this interpretation would be in conflict with the common belief that neutron stars have neutrons in a superfluid state and protons in a superconductive one.
Stratified sampling for data mining on the deep web

In recent years, the deep web has become extremely popular. Like any other data source, data mining on the deep web can produce important insights or summaries of results. However, data mining on the deep web is challenging because the databases cannot be accessed directly, and therefore, data mining must be performed by sampling the datasets. The samples, in turn, can only be obtained by querying deep web databases with specific inputs. In this paper, we target two related data mining problems, association mining and differential rulemining. These are proposed to extract high-level summaries of the differences in data provided by different deep web data sources in the same domain. We develop stratified sampling methods to perform these mining tasks on a deep web source. Our contributions include a novel greedy stratification approach, which recursively processes the query space of a deep web data source, and considers both the estimation error and the sampling costs. We have also developed an optimized sample allocation method that integrates estimation error and sampling costs. Our experimental results show that our algorithms effectively and consistently reduce sampling costs, compared with a stratified sampling method that only considers estimation error. In addition, compared with simple random sampling, our algorithm has higher sampling accuracy and lower sampling costs.
Phase-only synthesis for multiple beam phased arrays with element failures

Interference between beams of a multiple-beam phased array can be minimized by reducing the sidelobes of each beam in the overlap area. The sidelobe reduction can be accomplished by adjusting the phase and/or amplitude distribution across the face of the array. Since changing the amplitude distribution reduces the efficiency of the array, changing phase-only has been investigated. The algorithm presented numerically solves for the phase on each antenna element required to minimize the beam interference under the constraint where some elements have failed. >
Organizational Adoption of Web 2.0 Technologies: An Empirical Analysis

While Web 2.0 technologies such as blogs, wikis, and social networks have been popular in the consumer space, there is significant variation in adoption of Web 2.0 technologies in business. Yet, little is known about why firms adopt Web 2.0 technologies. There is a paucity of empirical research examining the antecedents of the use of Web 2.0 technologies in organizations. Drawing on the Technological-Organizational-Environmental theoretical framework, our study presents and empirically tests a model of factors associated with organizational adoption of Web 2.0 technologies. We find that importance to open standards is positively associated with the propensity for adoption of Web 2.0 technologies. Further, larger organizations are found to have a higher propensity for adoption. Finally, industry knowledge intensity is found to be positively associated with a higher propensity for adoption. Our results suggest that open architectures, firm size, and industry knowledge intensity play pivotal roles in Web 2.0...
Do Security Analysts Speak in Two Tongues

Why do security analysts issue overly positive recommendations? We propose a novel approach to distinguish strategic motives (e.g., generating small-investor purchases and pleasing management) from nonstrategic motives (genuine overoptimism). We argue that nonstrategic distorters tend to issue both positive recommendations and optimistic forecasts, while strategic distorters "speak in two tongues," issuing overly positive recommendations but less optimistic forecasts. We show that the incidence of strategic distortion is large and systematically related to proxies for incentive misalignment. Our "two-tongues metric" reveals strategic distortion beyond those indicators and provides a new tool for detecting incentives to distort that are hard to identify otherwise.
Time-Domain Interference Cancellation for ALAMOUTI-Coded Cooperative OFDM Systems With Insufficient CP

Orthogonal frequency-division multiplexing (OFDM) transmission has been proposed in the literature for relay nodes to combat the time delays from the relay nodes, where the paths from relay nodes to the destination node are treated as multipaths, and space-time (or frequency) coding is used to achieve spatial (or multipath) diversity. With this approach, when the cyclic prefix (CP) length is less than the time-delay length, interblock interference occurs. In this paper, we consider Alamouti coded OFDM systems in cooperative communications where the CP length may be less than the time delay length. By taking the advantage of the Alamouti code structure, we propose a time-domain interference-cancellation algorithm. Simulation results show that the performance is significantly improved with our newly proposed time-domain interference-cancellation algorithm.
M31 Transverse Velocity and Local Group Mass from Satellite Kinematics

We present several different statistical methods to determine the transverse velocity vector of M31. The underlying assumptions are that the M31 satellites on average follow the motion of M31 through space and that the galaxies in the outer parts of the Local Group on average follow the motion of the Local Group barycenter through space. We apply the methods to the line-of-sight velocities of 17 M31 satellites, to the proper motions of the two satellites M33 and IC 10, and to the line-of-sight velocities of five galaxies near the Local Group turnaround radius, respectively. This yields four independent but mutually consistent determinations of the heliocentric M31 transverse velocities in the west and north directions, with weighted averages -->vW = − 78 ± 41 km s−1 and -->vN = − 38 ± 34 km s−1. The uncertainties correspond to proper motions of ~10 μas yr−1, which will be difficult to verify observationally within the next decade. The galactocentric tangential velocity of M31 is 42 km s−1, with 1 σ confidence interval -->Vtan ≤ 56 km s−1. The implied M31-Milky Way orbit is bound if the total Local Group mass M exceeds -->1.72−0.25+0.26 × 1012 M☉. If the orbit is indeed bound, then the timing argument combined with the known age of the universe implies that -->M = 5.58−0.72+0.85 × 1012 M☉. This is on the high end of the allowed mass range suggested by cosmologically motivated models for the individual structure and dynamics of M31 and the Milky Way, respectively. It is therefore possible that the timing mass is an overestimate of the true mass, especially if one takes into account recent results from the Millenium Simulation that show that there is also a theoretical uncertainty of 41% (Gaussian dispersion) in timing mass estimates. The M31 transverse velocity implies that M33 is in a tightly bound orbit around M31. This may have led to some tidal deformation of M33. It will be worthwhile to search for observational evidence of this.
Dirichlet–Laplace Priors for Optimal Shrinkage

Penalized regression methods, such as L1 regularization, are routinely used in high-dimensional applications, and there is a rich literature on optimality properties under sparsity assumptions. In the Bayesian paradigm, sparsity is routinely induced through two-component mixture priors having a probability mass at zero, but such priors encounter daunting computational problems in high dimensions. This has motivated continuous shrinkage priors, which can be expressed as global-local scale mixtures of Gaussians, facilitating computation. In contrast to the frequentist literature, little is known about the properties of such priors and the convergence and concentration of the corresponding posterior distribution. In this article, we propose a new class of Dirichlet–Laplace priors, which possess optimal posterior concentration and lead to efficient posterior computation. Finite sample performance of Dirichlet–Laplace priors relative to alternatives is assessed in simulated and real data examples.
Analysis of Polypeptide Movement in the SecY Channel during SecA-mediated Protein Translocation

In bacteria most secretory proteins are transported across the plasma membrane by the interplay of the ATPase SecA with the translocation channel formed by the SecY complex; SecA uses cycles of ATP hydrolysis to “push” consecutive segments of a polypeptide substrate through the channel. Here we have addressed the mechanism of this process by following the fate of stalled translocation intermediates. These were generated by using a polypeptide substrate containing a bulky disulfide-bonded loop, thus preventing the final residues from passing through the channel. Protease protection experiments showed that the intermediates were stable in the presence of ATP and could complete translocation once the block was removed. The translocation intermediate was also stable when SecA associated with ATPγS, a poorly hydrolyzable ATP analog, or ADP plus AlF4, which mimics the transition state during ATP hydrolysis. In contrast, when SecA was in its ADP-bound state, the translocating polypeptide moved back into the cytosol, as indicated by the disappearance of the protected fragment. Backsliding was not significantly altered by deletion of the plug domain, a short helix in the center of the SecY channel, but it was slowed down when changes were introduced into the pore ring, the constriction of the hourglass-shaped channel. In all cases, backsliding was significantly slower than forward translocation. Together, these data suggest that SecA binds the polypeptide chain in its ATP state and releases it in the ADP state. The channel itself does not bind the polypeptide chain but provides “friction” that minimizes backsliding when ADP-bound SecA resets to “grab” the next segment of the substrate.
Correlation chemical shift imaging with low-power adiabatic pulses and constant-density spiral trajectories.

In this work we introduce the concept of correlation chemical shift imaging (CCSI). Novel CCSI pulse sequences are demonstrated on clinical scanners for two-dimensional Correlation Spectroscopy (COSY) and Total Correlation Spectroscopy (TOCSY) imaging experiments. To date there has been limited progress reported towards a feasible and robust multivoxel 2D COSY. Localized 2D TOCSY imaging is shown for the first time in this work. Excitation with adiabatic GOIA-W(16,4) pulses (Gradient Offset Independent Adiabaticity Wurst modulation) provides minimal chemical shift displacement error, reduced lipid contamination from subcutaneous fat, uniform optimal flip angles, and efficient mixing for coupled spins, while enabling short repetition times due to low power requirements. Constant-density spiral readout trajectories are used to acquire simultaneously two spatial dimensions and f2 frequency dimension in (kx,ky,t2) space in order to speed up data collection, while f1 frequency dimension is encoded by consecutive time increments of t1 in (kx,ky,t1,t2) space. The efficient spiral sampling of the k-space enables the acquisition of a single-slice 2D COSY dataset with an 8 × 8 matrix in 8:32 min on 3 T clinical scanners, which makes it feasible for in vivo studies on human subjects. Here we present the first results obtained on phantoms, human volunteers and patients with brain tumors. The patient data obtained by us represent the first clinical demonstration of a feasible and robust multivoxel 2D COSY. Compared to the 2D J-resolved method, 2D COSY and TOCSY provide increased spectral dispersion which scales up with increasing main magnetic field strength and may have improved ability to unambiguously identify overlapping metabolites. It is expected that the new developments presented in this work will facilitate in vivo application of 2D chemical shift correlation MRS in basic science and clinical studies. Copyright © 2011 John Wiley & Sons, Ltd.