cssi/SciSciGPT-SciSciNet huggingface dataset:
Zigzag-base folded sheet cellular mechanical metamaterials

Abstract The Japanese art of turning flat sheets into three dimensional intricate structures, origami, has inspired design of mechanical metamaterials. Mechanical metamaterials are artificially engineered materials with uncommon properties. Miura-ori is a remarkable origami folding pattern with metamaterial properties and a wide range of applications. In this study, by dislocating the zigzag strips of a Miura-ori pattern along the joining ridges, we create a class of one-degree of freedom (DOF) cellular mechanical metamaterials. The unit cell of the patterns comprises two zigzag strips surrounding a hole with a parallelogram shape. We show that dislocating zigzag strips of the Miura-ori along the joining ridges preserves and/or tunes the outstanding properties of the Miura-ori. The introduced materials are lighter than their corresponding Miura-ori sheets due to the presence of holes in the patterns. Moreover, they are amenable to similar modifications available for Miura-ori which make them appropriate for a wide range of applications across the length scales.
Optimal partially reversible investment

Abstract Investment is partially reversible if there is a wedge between the prices at which a firm can buy and sell capital. We derive the optimal investment strategy for a risk-neutral firm with partially reversible investment when capital prices and the shocks to capital's marginal revenue product evolve as geometric Brownian motion. We examine some of the effects of increased uncertainty on the optimal investment strategy and on the long-run average growth rate of capital, and we argue that the long-run average growth rate of capital is the same whether investment is completely reversible, partially reversible, or completely irreversible.
Symmetries of baryons and mesons

The system of strongly interacting particles is discussed, with electromagnetism, weak interactions, and gravitation considered as perturbations. The electric current jα, the weak current Jα, and the gravitational tensor θαβ are all well-defined operators, with finite matrix elements obeying dispersion relations. To the extent that the dispersion relations for matrix elements of these operators between the vacuum and other states are highly convergent and dominated by contributions from intermediate one-meson states, we have relations like the Goldberger-Treiman formula and universality principles like that of Sakurai according to which the ρ meson is coupled approximately to the isotopic spin. Homogeneous linear dispersion relations, even without subtractions, do not suffice to fix the scale of these matrix elements; in particular, for the nonconserved currents, the renormalization factors cannot be calculated, and the universality of strength of the weak interactions is undefined. More information than just the dispersion relations must be supplied, for example, by field-theoretic models; we consider, in fact, the equal-time commutation relations of the various parts of j4 and J4. These nonlinear relations define an algebraic system (or a group) that underlies the structure of baryons and mesons. It is suggested that the group is in fact U(3)×U(3), exemplified by the symmetrical Sakata model. The Hamiltonian density θ44 is not completely invariant under the group; the noninvariant part transforms according to a particular representation of the group; it is possible that this information also is given correctly by the symmetrical Sakata model. Various exact relations among form factors follow from the algebraic structure. In addition, it may be worthwhile to consider the approximate situation in which the strangeness-changing vector currents are conserved and the Hamiltonian is invariant under U(3); we refer to this limiting case as "unitary symmetry." In the limit, the baryons and mesons form degenerate supermultiplets, which break up into isotopic multiplets when the symmetry-breaking term in the Hamiltonian is "turned on." The mesons are expected to form unitary singlets and octets; each octet breaks up into a triplet, a singlet, and a pair of strange doublets. The known pseudoscalar and vector mesons fit this pattern if there exists also an isotopic singlet pseudoscalar meson χ0. If we consider unitary symmetry in the abstract rather than in connection with a field theory, then we find, as an attractive alternative to the Sakata model, the scheme of Ne'eman and Gell-Mann, which we call the "eightfold way"; the baryons N, Λ, Σ, and Ξ form an octet, like the vector and pseudoscalar meson octets, in the limit of unitary symmetry. Although the violations of unitary symmetry must be quite large, there is some hope of relating certain violations to others. As an example of the methods advocated, we present a rough calculation of the rate of K+→μ++ν in terms of that of π+→μ++ν.
UNEARTHING T. REX: THE LAW AND ECONOMICS OF PALEONTOLOGICAL FINDS

This paper assesses the economic aspects of the search for and recovery of fossils on U.S. lands. The objective is taken to be the maximization of the social value of these resources, including the market and scientific values. Because independent searchers may not internalize the scientific value, we develop a reward scheme that incentivizes both optimal recovery of finds, and optimal search. We then trace how U.S. federal and state laws have tried to strike a balance between search activity and scientific recovery. We argue that existing law deals well with recovery but does not generally promote optimal search. (JEL D83, H41, I23, K11, O32)
Search for muon-electron and muon-positron conversion.

Limits on the lepton-flavor-violating reactions ${\ensuremath{\mu}}^{\mathrm{\ensuremath{-}}}$+Z\ensuremath{\rightarrow}${e}^{\mathrm{\ensuremath{-}}}$+Z and ${\ensuremath{\mu}}^{\mathrm{\ensuremath{-}}}$+Z\ensuremath{\rightarrow}${e}^{+}$+(Z-2), muon-electron and muon-positron conversion, have been obtained from a search performed at TRIUMF using a time-projection chamber. Upper limits (90% C.L.) for the branching ratios compared to ordinary muon capture for a titanium target are R---(Ti)=\ensuremath{\Gamma}(${\mathrm{\ensuremath{\mu}}}^{\mathrm{\ensuremath{-}}}$Ti\ensuremath{\rightarrow}${\mathit{e}}^{\mathrm{\ensuremath{-}}}$Ti)/\ensuremath{\Gamma}(${\mathrm{\ensuremath{\mu}}}^{\mathrm{\ensuremath{-}}}$Ti capture)4.6\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}12}$ and ${\mathit{R}}_{+}$(Ti)=\ensuremath{\Gamma}(${\mathrm{\ensuremath{\mu}}}^{\mathrm{\ensuremath{-}}}$Ti\ensuremath{\rightarrow}${\mathit{e}}^{+}$Ca*)/\ensuremath{\Gamma}(${\mathrm{\ensuremath{\mu}}}^{\mathrm{\ensuremath{-}}}$Ti capture).1.7\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}10}$ A smaller data set obtained using a lead target yielded ${R}_{\mathrm{\ensuremath{-}}}$(Pb)4.9\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}10}$. The implications of these results for extensions of the standard model which allow lepton-flavor violation are discussed.
Dense Chern-Simons Matter with Fermions at Large N

In this paper we investigate properties of Chern-Simons theory coupled to massive fermions in the large N limit. We demonstrate that at low temperatures the system is in a Fermi liquid state whose features can be systematically compared to the standard phenomenological theory of Landau Fermi liquids. This includes matching microscopically derived Landau parameters with thermodynamic predictions of Landau Fermi liquid theory. We also calculate the exact conductivity and viscosity tensors at zero temperature and finite chemical potential. In particular we point out that the Hall conductivity of an interacting system is not entirely accounted for by the Berry flux through the Fermi sphere. Furthermore, investigation of the thermodynamics in the non-relativistic limit reveals novel phenomena at strong coupling. As the ’t Hooft coupling λ approaches 1, the system exhibits an extended intermediate temperature regime in which the thermodynamics is described by neither the quantum Fermi liquid theory nor the classical ideal gas law. Instead, it can be interpreted as a weakly coupled quantum Bose gas.
Online Set Cover with Set Requests

We consider a generic online allocation problem that generalizes the classical online set cover framework by considering requests comprising a set of elements rather than a single element. This problem has multiple applications in cloud computing, crowd sourcing, facility planning, etc. Formally, it is an online covering problem where each online step comprises an offline covering problem. In addition, the covering sets are capacitated, leading to packing constraints. We give a randomized algorithm for this problem that has a nearly tight competitive ratio in both objectives: overall cost and maximum capacity violation. Our main technical tool is an online algorithm for packing/covering LPs with nested constraints, which may be of interest in other applications as well.
Understanding and Measuring Coach–Teacher Alliance: A Glimpse Inside the ‘Black Box’

Coaching models are increasingly used in schools to enhance fidelity and effectiveness of evidence-based interventions; yet, little is known about the relationship between the coach and teacher (i.e., coach–teacher alliance), which may indirectly enhance teacher and student outcomes through improved implementation quality. There is also limited research on measures of coach–teacher alliance, further hindering the field from understanding the active components for successful coaching. The current study examined the factor structure and psychometric characteristics of a measure of coach–teacher alliance as reported by both teachers and coaches and explored the extent to which teachers and coaches reliably rate their alliance. Data come from a sample of 147 teachers who received implementation support from one of four coaches; both the teacher and the coach completed an alliance questionnaire. Separate confirmatory factor analyses for each informant revealed four factors (relationship, process, investment, and perceived benefits) as well as an additional coach-rated factor (perceived teacher barriers). A series of analyses, including cross-rater correlations, intraclass correlation coefficients, and Kuder-Richardson reliability estimates suggested that teachers and coaches provide reliable, though not redundant, information about the alliance. Implications for future research and the utilization of the parallel coach–teacher alliance measures to increase the effectiveness of coaching are discussed.
Real time crack detection using mountable comparative vacuum monitoring sensors

Current maintenance operations and integrity checks on a wide array of structures require personnel entry into normally-inaccessible or hazardous areas to perform necessary nondestructive inspections. To gain access for these inspections, structure must be disassembled and removed or personnel must be transported to remote locations. The use of in-situ sensors, coupled with remote interrogation, can be employed to overcome a myriad of inspection impediments stemming from accessibility limitations, complex geometries, the location and depth of hidden damage, and the isolated location of the structure. Furthermore, prevention of unexpected flaw growth and structural failure could be improved if on-board health monitoring systems were used to more regularly assess structural integrity. A research program has been completed to develop and validate Comparative Vacuum Monitoring (CVM) Sensors for surface crack detection. Statistical methods using one-sided tolerance intervals were employed to derive Probability of Detection (POD) levels for a wide array of application scenarios. Multi-year field tests were also conducted to study the deployment and long-term operation of CVM sensors on aircraft. This paper presents the quantitative crack detection capabilities of the CVM sensor, its performance in actual flight environments, and the prospects for structural health monitoring applications on aircraft and other civil structures.
An improved neoclassical drift-magnetohydrodynamical fluid model of helical magnetic island equilibria in tokamak plasmas

The effect of the perturbed ion polarization current on the stability of neoclassical tearing modes in tokamak plasmas is calculated using an improved, neoclassical, four-field, drift-magnetohydrodynamical model. The calculation involves the self-consistent determination of the pressure and scalar electric potential profiles in the vicinity of the associated magnetic island chain, which allows the chain's propagation velocity to be fixed. Two regimes are considered. First, a regime in which neoclassical ion poloidal flow damping is not strong enough to enhance the magnitude of the polarization current (relative to that found in slab geometry). Second, a regime in which neoclassical ion poloidal flow damping is strong enough to significantly enhance the magnitude of the polarization current. In both regimes, two types of solution are considered. First, a freely rotating solution (i.e., an island chain that is not interacting with a static, resonant, magnetic perturbation). Second, a locked solution (i.e., an island chain that has been brought to rest in the laboratory frame via interaction with a static, resonant, magnetic perturbation). In all cases, the polarization current is found to be either always stabilizing or stabilizing provided that ηi≡dlnTi/dlnne does not exceed some threshold value. In certain ranges of ηi, the polarization current is found to have a stabilizing effect on a freely rotating island, but a destabilizing effect on a corresponding locked island.
Cincuenta años de uso y mal-uso de El Niño

El Nino de 1957-58 fue el evento que puso a este fenomeno bajo la atencion del mundo cientifico. El fenomeno no solo coincidio con la celebracion del Ano Geofisico Internacional sino tambien con la publicacion de un importante articulo de H.P. Berlage en el cual se hace referencia a la existencia y a los efectos de la Oscilacion del Sur (Southern Oscillation) en el Oceano Pacifico. Los efectos de El Nino 1957-58 provocaron el interes por este fenomeno por parte de climatologos tan eminentes como Bjerknes, Flohn, y Namias, quienes empezaron a notar la existencia de "teleconexiones" mas alla de America del Sur y del Pacifico tropical. Sin embargo, El Nino 1972-73 fue el evento que revelo mas claramente los efectos mundiales del fenomeno y atrajo la atencion de nuevos geofisicos, oceanografos, ecologos, geografos y politologos. Las repeticiones de este fenomeno en 1976-77, 1982-83, 1992-94, lo convirtieron en un concepto de conocimiento general que tambien esta llevando a un ulterior "uso" y "abuso" como son los casos de "La Nina" y "El Viejo".
Effect of branding Gulf oysters on consumers willingness to pay

Using a choice experiment this study found that raw oyster consumers are more likely to buy oysters harvested from their region over those harvested outside the region. Consumers are more likely to buy wild-caught oysters over cultivated oysters. Non-Gulf consumers are more likely to buy medium or large size oysters over small size.
A general unified approach to modelling switching-converter power stages

A method for modelling switching-converter power stages is developed, whose starting-point is the unified state-space representation of the switched notworks and whose end result is either a complete state-space description or its equivalent small-signal low-frequency linear circuit model. A new canonical circuit model is proposed, whose fixed topology contains all the essential input-output and control properties of any d.c.-to-d.c. switching converter, regardless of its detailed configuration, and by which different converters can be characterized in the form of a table conveniently stored in a computer data bank to provide a useful tool for computer-aided design and optimization. The new canonical circuit model predicts that, in general, switching action introduces both zeros and poles into the duty ratio to output transfer function in addition to those from the effective filter network.
Analyzing proposals for improving authentication on the TLS-/SSL-protected Web

"Secure" Web browsing with HTTPS uses TLS/SSL and X.509 certificates to provide authenticated, confidential communication between Web clients and Web servers. The authentication component of the system has a variety of weaknesses, which have led to a variety of proposals for improving the current environment. In this paper, we survey, analyze, compare and contrast five prominent proposals. To do this, we attempt to systematically capture the properties one might require of such a system: authentication properties, forensics/privacy properties, usability properties and pragmatic properties. Enumerating these properties is an important part of understanding these proposals and the nature of the authentication problem for the secure Web. Finally, we offer a few conclusions and suggestions pertaining to these proposals and possible future directions of research.
The effect of state health insurance benefit mandates on premiums and employee contributions

ABSTRACTThe average US state has 40 benefit mandates, laws requiring health insurance to cover particular conditions, treatments, providers or people. We investigate the extent to which these mandates increase the health insurance premiums paid by employers, and the extent to which these higher premiums are passed on to employees in the form of higher employee contributions. We use state-level data on premiums and employee contributions to health insurance from the insurance component of the 1996–2011 Medical Expenditure Panel Survey. Our main analysis is a fixed effects regression that controls for age, race, income, union membership and the presence of state mandate waivers. We find robust evidence that the average mandate increases premiums by approximately 0.6%, and that mandates lead to similar increases in employee contributions for single-coverage health insurance plans. Alternative specifications using an AR(1) error structure estimate a larger effect of mandates, while those using generalized est...
What happens when the definition of disability changes? The case of obesity

This paper examines how Congress’s 2008 expansion of who is disabled under the Americans with Disabilities Act (ADA) impacts the labor market outcomes of newly covered individuals. Focusing on obese individuals, I exploit variation in coverage of obesity before and after the 2008 expansion to identify effects of the legal change, but I find no improvement in the labor market outcomes of the obese. Although the 2008 expansion was intended to remedy the unintended consequences of the ADA and improve labor market outcomes of the disabled, these early estimates suggest that the expansion has not yet achieved Congress’s stated goals. JEL codes: J14, J21, J78, K31
Bans vs. Fees: Disposable Carryout Bag Policies and Bag Usage

Using observational data on consumer carryout bag usage, we measure the effects of disposable bag policies on disposable and reusable bag demand. Our results show that plastic bag bans coupled with paper bag fees decrease total disposable bag demand but lead to significant increases in paper bag consumption. We compare our results to a study on bag fees and find that both policies lead to similar increases in reusable bag usage. However, the success of bans versus fees in discouraging disposable bag usage is contingent upon the types and prices of bags that stores choose to sell in lieu of disposable plastic.
Transient Low Testosterone Levels After Oral Hydrocodone May Contribute to Misdiagnosis of Hypogonadism

Alterations in luteinizing hormones and testosterone levels following short-acting opioid ingestion are unknown but may assist in the diagnosis of hypogonadism in opioid consumers. Serial luteinizing hormones and testosterone values were measured every 2 hours for 10 hours following ingestion of either 0, 5, or 10 mg of hydrocodone on multiple isolated occasions, and demonstrated testosterone levels 2 and 4 hours after 10 mg ingestion to be 25% lower than those after 0 or 5 mg, with this difference resolving within 8 post-ingestion hours, indicating that knowledge of recent hydrocodone ingestion may be valuable in interpreting the significance of low morning testosterone levels in some patients. J Endocrinol Metab. 2016;6(1):18-20 doi: http://dx.doi.org/10.14740/jem324w
A Neural Approach to Blind Motion Deblurring

We present a new method for blind motion deblurring that uses a neural network trained to compute estimates of sharp image patches from observations that are blurred by an unknown motion kernel. Instead of regressing directly to patch intensities, this network learns to predict the complex Fourier coefficients of a deconvolution filter to be applied to the input patch for restoration. For inference, we apply the network independently to all overlapping patches in the observed image, and average its outputs to form an initial estimate of the sharp image. We then explicitly estimate a single global blur kernel by relating this estimate to the observed image, and finally perform non-blind deconvolution with this kernel. Our method exhibits accuracy and robustness close to state-of-the-art iterative methods, while being much faster when parallelized on GPU hardware.
Secure state estimation for nonlinear power systems under cyber attacks

This paper focuses on securely estimating the state of a nonlinear dynamical system from a set of corrupted measurements. In particular, we consider a wide class of nonlinear systems, and propose a technique which enables us to perform secure state estimation for such nonlinear systems. We then provide guarantees on the achievable state estimation error against arbitrary corruptions, and analytically characterize the number of errors that can be perfectly corrected by a decoder. To illustrate how the proposed nonlinear estimation approach can be applied to practical systems, we focus on secure estimation for the wide area control of an interconnected power system under cyber-physical attacks and communication failures, and propose a secure estimator for the power system. Finally, we numerically show that the proposed secure estimation algorithm enables us to reconstruct the attack signals accurately.
Cross-Electrophile Coupling of Vinyl Halides with Alkyl Halides

An improved method for the reductive coupling of aryl and vinyl bromides with alkyl halides that gave high yields for a variety of substrates at room temperature with a low (2.5 to 0.5 mol %) catalyst loading is presented. Under the optimized conditions, difficult substrates, such as unhindered alkenyl bromides, can be coupled to give the desired olefins with minimal diene formation and good stereoretention. These improved conditions also worked well for aryl bromides. For example, a gram-scale reaction was demonstrated with 0.5 mol % catalyst loading, whereas reactions at 10 mol % catalyst loading completed in as little as 20 minutes. Finally, a low-cost single-component pre-catalyst, (bpy)NiI2 (bpy=2,2′-bipyridine) that is both air- and moisture-stable over a period of months was introduced.
MEASUREMENT OF SERUM COMPLEMENT DURING HOMOGRAFT REJECTION IN MAN AND RAT.

SummaryIn the rat, active homograft rejection of skin, whether first set, second set, or “white” does not alter the serum whole complement titer (CH50). During renal homograft rejection in man there is a small reduction in the CH50 titer, and a pronounced diminution in the titer of the second component of human complement (C'2hu), presumably reflecting in vivo complement fixation.
Parameter Design Strategies: A Comparison Between Human Designers and the Simulated Annealing Algorithm

Computer-based tools have great potential for facilitating the design of large-scale engineering systems. Interviews with veteran designers of desalination systems revealed that they tended to employ a trial-and-error approach to determine critical design parameters when using software design packages. A series of human experiments were conducted to observe the performance and behavior of test subjects during a series of simulated design processes involving seawater reverse osmosis (SWRO) plants. The subjects were mostly students with a spectrum of knowledge levels in desalination system design. The experiments showed that subjects who ranked top in performance behaved very differently from those who were bottom-ranked. The problem-solving profiles of the best performing subjects resembled a well-tuned simulated annealing optimization algorithm while the worst performing subjects used a pseudo random search strategy. This finding could be used to improve computer-based design tools by utilizing the synergy between strengths of humans and computers.Copyright © 2015 by ASME
Stress-Strain Relation of Pure-Gum Rubber Vulcanizates in Compression and Tension

Abstract The empirical function of Martin, Roth, and Stiehler represented by Eq. (1) where A has the value of 0.38 may be regarded as an adequate representation of the available experimental data covering both the compression and tension of pure-gum vulcanizates. The stress and strain are to be measured after a constant time of creep. The approximate validity extends over the range 0.5<L<3.5. The success of the single empirical function in representing data obtained in both compression and tension over a range as great as this is regarded as very significant. In the range of values of L from 0.5 to 1.0 (compression) the empirical function gives results in agreement with the predictions of the statistical theory of rubber elasticity. After representing the stress and strain in a transition region extending from L=1.0 to 1.5, the empirical function gives approximately constant coefficients C1and C2 in the Mooney equation over the range from 1.5 to about 3.5. The behavior of the empirical function in the tra...
An efficient method for the preparation of styrene derivatives via Rh(III)-catalyzed direct C-H vinylation.

The development of a method for the Rh(III)-catalyzed direct vinylation of an aromatic C–H bond to give functionalized styrenes in good yield, using vinyl acetate as a convenient and inexpensive vinyl source, is reported. High functional group tolerance is demonstrated for electronically distinct arenes as well as different directing groups. Mechanistic investigation resulted in the characterization of a novel rhodium–metallacycle, which represents the first X-ray structure of a [1,2]-Rh(III)-alkenyl addition adduct.
Temperature dependent I-V characteristics of AlGaN/GaN HBTs and GaN BJTs

DC I-V characteristics of AlGaN/GaN heterojunction bipolar transistors (HBTs) and GaN homojunction bipolar transistors (BJTs) are analyzed in the temperature range of 200-450 K. At low current levels, the adverse effects of poor ohmic contacts coupled with paths of high leakage make it difficult to extract intrinsic device operation ["Explanation of anomalous current gain observed in GaN based bipolar transistors", Xing et al. IEEE Elect. Dev. Lett. 24(1) 2003:p.4-6]. At intermediate current levels, owing to enhanced ionization of Mg in the base, the HBTs show an increase in current gain resulting from mitigated current crowding, and the BJTs show a decrease in current gain resulting from reduction of emitter injection coefficient. The offset voltage dependence on temperature is also explained.
On the Efficiency of Social Recommender Networks

We study a fundamental question that arises in social recommender systems: whether it is possible to simultaneously maximize: 1) an individual's benefit from using a social network, and 2) the efficiency of the network in disseminating information. To tackle this question, our study consists of three components. First, we introduce a stylized stochastic model for recommendation diffusion. Such a model allows us to highlight the connection between user experience at the individual level, and network efficiency at the macroscopic level. We also propose a set of metrics for quantifying both user experience and network efficiency. Second, based on these metrics, we extensively study the tradeoff between the two factors in a Yelp dataset, concluding that Yelp's social network is surprisingly efficient, though not optimal. Finally, we design a friend recommendation and news feed curation algorithm that can simultaneously address individuals' need to connect to high-quality friends, and service providers' need to maximize network efficiency in information propagation.
Identification of Pressure-Induced Phase Transformations Using Nanoindentation

A combination of depth-sensing indentation and Raman microspectroscopy has been used for the identification of pressure-induced phase transformations in silicon, germanium, boron carbide and partially stabilized zirconia single crystals. Phase transformations during nanoindentation may be revealed through deviations in the shape of the load-displacement curves from that of a perfect elastoplastic material. Such deviations are often more readily identified if the nanoindentation data are presented as average contact pressure vs. contact depth curves, allowing assessment of the corresponding transformation pressures.
Near Field Scanning Optical Microscopy and Spectroscopy of Electronic Materials and Structures

A Near Field Scanning Optical Microscope (NSOM) with spectroscopic capability is applied to imaging semiconductor and microelectronic structures. NSOM combined with spectroscopic analysis provides physical and chemical information of thin films and defects with ultra high spatial resolution. We have studied epitaxial and bulk samples and partially fabricated SiO2/Si CMOS structures to investigate the spatial resolution and imaging modes of NSOM. Reflected intensity contrast in NSOM yields images of defect networks in InGaAs/InAlAs/GaAs epitaxial layers and shows thickness variations in SiO2 films on Si. Surface topological changes observed in NSOM demonstrate a spatial resolution of significantly better than 0.25 µm. Fluorescence imaging is examined for chemically identifying materials and defects.
Creation of a Surgical Fontan Animal Model and the Use of a Ventricular Assist Device to Restore Cardiac Output

Current ventricular assist devices are not designed for use in patients with failing Fontans. This study evaluated the efficacy of the Jarvik 2000 ventricular assist device (VAD) as a pulmonary pump to power a Fontan circuit in a large animal model. Without the use of cardiopulmonary bypass, Fontan
Assessing the Effects of Silver Nanoparticles on Biological Nutrient Removal in Bench-Scale Activated Sludge Sequencing Batch Reactors

Consumer products such as clothing and medical products are increasingly integrating silver and silver nanoparticles (AgNPs) into base materials to serve as an antimicrobial agent. Thus, it is critical to assess the effects of AgNPs on wastewater microorganisms essential to biological nutrient removal. In the present study, pulse and continuous additions of 0.2 and 2 ppm gum arabic and citrate coated AgNPs as well as Ag as AgNO3 were fed into sequencing batch reactors (SBRs) inoculated with nitrifying sludge. Treatment efficiency (chemical oxygen demand (COD) and ammonia removal), Ag dissolution measurements, and 16S rRNA bacterial community analyses (terminal restriction fragment length polymorphism, T-RFLP) were performed to evaluate the response of the SBRs to Ag addition. Results suggest that the AgNPs may have been precipitating in the SBRs. While COD and ammonia removal decreased by as much as 30% or greater directly after spikes, SBRs were able to recover within 24 h (3 hydraulic retention times (H...
A Space-Vector-Modulated Sensorless Direct-Torque Control for Direct-Drive PMSG Wind Turbines

This paper proposes a space-vector modulation (SVM)-based direct-torque control (DTC) scheme for a permanent-magnet synchronous generator (PMSG) used in a variable-speed direct-drive wind power generation system. A quasi-sliding-mode observer that uses a relatively low sampling frequency, e.g., 5 or 10 kHz, is proposed to estimate the rotor position and stator flux linkage based on the current model of the PMSG over a wide operating range. The optimal torque command is directly obtained from the estimated rotor speed for the DTC by which the maximum power point tracking control of the wind turbine generator is achieved without the need for wind speed or rotor position sensors. Compared with the conventional DTC, the proposed SVM-DTC achieves a fixed switching frequency and greatly reduces the flux and torque ripples, while retaining the fast dynamic response of the system. The effectiveness of the proposed SVM-DTC scheme is verified by simulation studies on a 1.5-MW PMSG wind turbine and is further verified by experimental results on a 2.4-kW PMSG with a 10-kHz sampling frequency.
On the efficient synthesis of efficient programs

Abstract Efficiency is a problem in automatic programming—both in the programs produced and in the synthesis process itself. The efficiency problem arises because many target-language programs (which vary in their time and space performance) typically satisfy one abstract specification. This paper presents a framework for using analysis and searching knowledge to guide program synthesis in a stepwise refinement paradigm. A particular implementation of the framework, called libra , is described. Given a program specification that includes size and frequency notes, the performance measure to be minimized, and some limits on synthesis resources, libra selects algorithms and data representations and decides whether to use ‘optimizing’ transformations. By applying incremental, algebraic program analysis, explicit rules about plausible implementations, and resource allocation on the basis of decision importance, libra has guided the automatic implementation of a number of programs in the domain of symbolic processing.
Site-selective and stereoselective functionalization of unactivated C–H bonds

Organic synthesis has traditionally relied heavily on the introduction and manipulation of functional groups, such as carbonoxygen or carbonhalogen bonds. Much current research is focused on a potentially powerful alternative strategy in which carbonhydrogen bonds, normally much less reactive and therefore resistant to functionalization, are somehow persuaded to be more easily modified. These authors report that it is possible to selectively functionalize an unactivated CH bond by the use of well-defined catalysts to control the site selectivity, without the need for a directing or anchoring group present in the molecule. They use dirhodium catalysts to achieve diastereoselective and enantioselective CH functionalization of n-alkanes and terminally substituted n-alkyl compounds. The reactions proceed in high yield and can be carried out on substrates containing other functional groups such as halides, silanes, and esters.
Patterns of demand for non-Ebola health services during and after the Ebola outbreak: panel survey evidence from Monrovia, Liberia

Introduction The recent Ebola virus disease (EVD) outbreak was unprecedented in magnitude, duration and geographic scope. Hitherto there have been no population-based estimates of its impact on non-EVD health outcomes and health-seeking behaviour. Methods We use data from a population-based panel survey conducted in the late-crisis period and two postcrisis periods to track trends in (1) the prevalence of adult and child illness, (2) subsequent usage of health services and (3) the determinants thereof. Results The prevalence of child and adult illness remained relatively steady across all periods. Usage of health services for children and adults increased by 77% and 104%, respectively, between the late-crisis period and the postcrisis periods. In the late-crisis period, (1) socioeconomic factors weakly predict usage, (2) distrust in government strongly predicts usage, (3) direct exposure to the EVD outbreak, as measured by witnessing dead bodies or knowing Ebola victims, negatively predicts trust and usage and (4) exposure to government-organised community outreach predicts higher trust and usage. These patterns do not obtain in the post-crisis period. Interpretation Supply-side and socioeconomic factors are insufficient to account for lower health-seeking behaviour during the crisis. Rather, it appears that distrust and negative EVD-related experiences reduced demand during the outbreak. The absence of these patterns outside the crisis period suggests that the rebound after the crisis reflects recovery of demand. Policymakers should anticipate the importance of demand-side factors, including fear and trust, on usage of health services during health crises.
The effect of diet on retention by the rat of iron from a radiolabeled casein test meal

Previous work has shown that weanling rats fed a soy protein isolate (SPI)-based diet retained less iron from a casein test meal than did rats fed a casein- based diet. In the present work this diet effect was further investigated. In experiment 1 rats were fed either SPI- or casein-based diet (about 25 ppm Fe) for 13 d, fasted over night, given a 59Fe-labeled casein-based test meal, and refed either the same or the other diet for 7 d. 59Feretention was determined by the percent of ingested label re tained after 7 d. SPI reduced 59Feretention when fed prior to the test meal (52.5 vs. 61.5%, P < 0.001) and also when fed following the test meal (50.8 vs. 63.2%, P < 0.001). In experiment 2a, exposure of SPI to steam at 108Â°Cfor 30 min did not lessen the observed diet effect. In experiment 2b rats were fed either an SPI- or casein- based diet, and casein test meals were fed as above on days 14, 35 and 56. The SPI- based diet reduced 58Fe retention from the casein test meal fed on d 14 (58.2 vs. 68.0 %, P < 0.005), for the meal on d 35 there was no difference, and for the final test meal rats fed SPI retained more 59Fe (53.0 vs. 40.2%, P < 0.01). In experiment 3 lactalbumin was shown to decrease59Fe retention to the same extent as SPI (54.9 and 53.4 %) as compared to casein (73.3 %), whereas neither rapeseed protein concentrate (68.8%) nor oxalic acid (72.2%) had any significant adverse effect. Clearly, protein source, duration of feeding, and diet before and after the test meal affect iron retention. J. Nutr. 115: 319-326, 1985.
Synthesis of Novel Fluoropicolinate Herbicides by Cascade Cyclization of Fluoroalkyl Alkynylimines

The cascade cyclization of fluoroalkyl alkynylimines with primary amines has been modified to allow the synthesis of 4-amino-5-fluoropicolinates. Use of N-trityl and acetal protecting groups in the cyclization precursor led to 5-fluoropyridines that were easily deprotected to picolinaldehyde derivatives for further elaboration to structures of interest as potential herbicides. This method provided access to picolinic acids with alkyl or aryl substituents at the 6-position that were previously inaccessible via cross-coupling chemistry.
Fistula in ano.

Fistula in ano nearly always originates from infection in the anal crypts of Morgagni. A tentative diagnosis can often be made from a careful history and examination. Operative techniques, including various methods for finding the internal opening and obscure branching tracts, as well as a number of pitfalls to be avoided, are described.
Can the Baryon Asymmetry Arise From Initial Conditions

In this paper, we quantify the challenge of explaining the baryon asymmetry using initial conditions in a universe that undergoes inflation. Contrary to lore, we find that such an explanation is possible if net $B\ensuremath{-}L$ number is stored in a light bosonic field with hyper-Planckian initial displacement and a delicately chosen field velocity prior to inflation. However, such a construction may require extremely tuned coupling constants to ensure that this asymmetry is viably communicated to the Standard Model after reheating; the large field displacement required to overcome inflationary dilution must not induce masses for Standard Model particles or generate dangerous washout processes. While these features are inelegant, this counterexample nonetheless shows that there is no theorem against such an explanation. We also comment on potential observables in the double $\ensuremath{\beta}$-decay spectrum and on model variations that may allow for more natural realizations.
Synthesis of 1,2,3,6-Tetrahydropyridines via Aminophosphate Enabled Anionic Cascade and Acid Catalyzed Cyclization Approaches

Two new approaches for forming 1,2,3,6-tetrahydropyridines are reported. Both reactions employ a strategic phosphate substituent on the nitrogen atom. In the presence of an additional phosphate substituent (X = P = O(OEt)2) an anionic cascade can by triggered upon treatment with base. Alternatively, when X = H the same 1,2,3,6-tetrahydropyridine product can be accessed via an acid catalyzed cyclization.
Coordination and culture

Culture constrains individual choice, rendering certain actions impermissible or taboo. While cultural constraints may regulate behavior within a group, they can have a pernicious effect in multicultural societies, inhibiting the emergence of unified social conventions. We analyze interactions between members of two cultural groups who are matched to play a coordination game with an arbitrary number of actions. Due to cultural constraints, miscoordination prevails despite strong incentives to coordinate behavior. In an application to identity-based conflict, exclusive ethnic and religious identities persist in poorer and more unequal societies. Occasional violation of cultural constraints can make miscoordination even more stable.
He never willed to have the will he has: Historicist narratives, “civilized” blame, and the need to distinguish two notions of free will.

Harsh blame can be socially destructive. This article examines how harsh blame can be “civilized.” A core construct here is the historicist narrative, which is a story-like account of how a person came to be the sort of person she is. We argue that historicist narratives regarding immoral actors can temper blame and that this happens via a novel mechanism. To illuminate that mechanism, we offer a novel theoretical perspective on lay beliefs about free will. We distinguish 2 senses of free will: (a) Freedom of action, which portrays the will as a dynamic choice-making mechanism and concerns whether the actor can exert volitional control via that mechanism at the time of action, and (b) Control of self-formation, which portrays the will as an enduring disposition (e.g., persistent desire to humiliate) and refers to whether the actor is truly the source of that disposition. Six experiments show that historicist narratives have no effect on perceived freedom of action, but rather temper blame by reducing perceived self-formative control. We also provide evidence against several additional theoretically derived alternative mediators (e.g., intentionality, perceived suffering). Further underlining the need to distinguish free will concepts, we show that biological narratives—unlike historicist narratives—temper blame via reductions in perceived freedom of action. Finally, to illuminate the meaning of “civilized” blame,” we show that historicist narratives specifically reduce the urge to inflict spiteful punishments on offenders, but leave intact the urge to nonviolently guide the offender toward moral improvement. (PsycINFO Database Record (c) 2017 APA, all rights reserved)
Development of a two-dimensional binning model for N2–N relaxation in hypersonic shock conditions

A high fidelity internal energy relaxation model for N2–N suitable for use in direct simulation Monte Carlo (DSMC) modeling of chemically reacting flows is proposed. A novel two-dimensional binning approach with variable bin energy resolutions in the rotational and vibrational modes is developed for treating the internal mode of N2. Both bin-to-bin and state-specific relaxation cross sections are obtained using the molecular dynamics/quasi-classical trajectory (MD/QCT) method with two potential energy surfaces as well as the state-specific database of Jaffe et al. The MD/QCT simulations of inelastic energy exchange between N2 and N show that there is a strong forward-preferential scattering behavior at high collision velocities. The 99 bin model is used in homogeneous DSMC relaxation simulations and is found to be able to recover the state-specific master equation results of Panesi et al. when the Jaffe state-specific cross sections are used. Rotational relaxation energy profiles and relaxation times obtained using the ReaxFF and Jaffe potential energy surfaces (PESs) are in general agreement but there are larger differences between the vibrational relaxation times. These differences become smaller as the translational temperature increases because the difference in the PES energy barrier becomes less important.
A theoretical review of diffusive shock acceleration

We discuss the fundamental ideas of particle acceleration in plasma shocks with emphasis on those features that are required to produce the 'universal' power-law spectrum. We compare shock acceleration with the more familiar second-order or stochastic acceleration and see that they are not too different in many respects. We discuss the features of shock acceleration that make it appealing and some of its problems as well.
Herding by mutual funds: impact on performance and investors’ response†

In this paper we investigate whether herding by actively managed equity funds affects their performances and flows over the 1980–2013 period. We show that during the herding quarter, on average, fu...
Characterization of optical quantum circuits using resonant phase shifts

We demonstrate that important information about linear optical circuits can be obtained through the phase shift induced by integrated optical resonators. As a proof of principle, the phase of an unbalanced Mach-Zehnder interferometer is determined. Then, the method is applied to a complex optical circuit designed for linear optical quantum computation. In this controlled-NOT gate with qubit initialization and tomography stages, the relative phases, as well as the coupling ratios of its directional couplers, are determined.
Database indexing methods for 3D hand pose estimation

Estimation of 3D hand pose is useful in many gesture recognition applications, ranging from human-computer interaction to recognition of sign languages. In this paper, 3D hand pose estimation is treated as a database indexing problem. Given an input image of a hand, the most similar images in a large database of hand images are retrieved. The hand pose parameters of the retrieved images are used as estimates for the hand pose in the input image. Lipschitz embeddings are used to map edge images of hands into a Euclidean space. Similarity queries are initially performed in this Euclidean space, to quickly select a small set of candidate matches. These candidate matches are finally ranked using the more computationally expensive chamfer distance. Using Lipschitz embeddings to select likely candidate matches greatly reduces retrieval time over applying the chamfer distance to the entire database, without significant losses in accuracy.