cssi/SciSciGPT-SciSciNet huggingface dataset:
Time‐Resolved Photoacoustic Calorimetry: From Carbenes to Proteins

Why have molecules only been seen but not heard? For over a century chemists have probed reactions with various spectroscopic methods to learn about structures, dynamics, and reactivities of their molecules. What they have not done is to listen to their molecules react. Although the photoacoustic phenomenon has been known since 1880, it is only in the last twenty years that technology has developed to the point where sound waves produced by reacting molecules can be time resolved and the information contained within the waves deciphered. The information content within the photoacoustic wave is indeed rich, for one can learn about the dynamics and the magnitude of enthalpy changes associated with the reaction as well as the changes in molecular volume. This review article chronicles the development of time-resolved photoacoustic calorimetry and its application to a variety of reactions encountered in organic and organometallic chemistry and biochemistry.
The Interface Chemistry between Chalcogenide Clusters and Open Framework Chalcogenides

One of the most exciting recent developments concerning molecular architectures is the emerging field of crystalline chalcogenide superlattices that bridges two traditional but distinct areas of research: chalcogenide clusters and porous materials. By combining synthetic and structural concepts in these two areas, many crystalline solids containing spatially organized chalcogenide clusters have been created that exhibit varied properties ranging from microporosity, fast ion conductivity, and photoluminescence to narrow and tunable electronic band gaps. The potential applications of these materials extend beyond traditional areas such as acid catalysis or adsorption-based separation to include shape- or size-selective photocatalysis, solid-state ionics, and electrochemistry.
Mixed initial-boundary value problems for scalar conservation laws: application to the modeling of transportation networks

This article proves the existence and uniqueness of a weak solution to a scalar conservation law on a bounded domain. A weak formulation of hybrid boundary conditions is needed for the problem to be well posed. The boundary conditions are represented by a hybrid automaton with switches between the modes determined by the direction of characteristics of the system at the boundary. The existence of the solution results from the convergence of a Godunov scheme derived in this article. This weak formulation is written explicitly in the context of a strictly concave flux function (relevant for highway traffic). The numerical scheme is then applied to a highway scenario with data from the I210 highway obtained from the California PeMS system. Finally, the existence of a minimizer of travel time is obtained, with the corresponding optimal boundary control.
Synthesis and characterization of a polyoxovanadate cluster representing a new topology.

A new type of mixed-valence polyoxoanionic cluster, [VV13VIV3O42(Cl)]8−, composed of 14 {VO5} square pyramids and 2 {VO4} tetrahedral units, hosting a chloride ion has been synthesized and characterized.
Feedback stabilization using two-hidden-layer nets

The representational capabilities of one-hidden-layer and two-hidden-layer nets consisting of feedforward interconnections of linear threshold units are compared. It is remarked that for certain problems two hidden layers are required, contrary to what might be in principle expected from the known approximation theorems. The differences are not based on numerical accuracy or number of units needed, nor on capabilities for feature extraction, but rather on a much more basic classification into direct and inverse problems. The former correspond to the approximation of continuous functions, while the latter are concerned with approximating one-sided inverses of continuous functions, and are often encountered in the context of inverse kinematics determination or in control questions. A general result is given showing that nonlinear control systems can be stabilized using two hidden layers, but not, in general, using just one. >
The Bayh-Dole Act of 1980 and University-Industry Technology Transfer: A Model for Other OECD Governments?

Recent initiatives by a number of OECD governments suggest considerable interest in emulating the Bayh-Dole Act of 1980, a piece of legislation that is widely credited with stimulating significant growth in university-industry technology transfer and research collaboration in the US. We examine the effects of Bayh-Dole on university-industry collaboration and technology transfer in the US, emphasizing the lengthy history of both activities prior to 1980 and noting the extent to which these activities are rooted in the incentives created by the unusual scale and structure (by comparison with Western Europe or Japan) of the US higher education system. Efforts at “emulation” of the Bayh-Dole policy elsewhere in the OECD are likely to have modest success at best without greater attention to the underlying structural differences among the higher education systems of these nations.
Fatigue in Dynamic Tournaments

Employee overwork and fatigue are a concern of managers in many organizations, as they may increase health and safety risks and decrease productivity. The problem is especially severe in competitive environments, where compensation and promotions are awarded, explicitly or implicitly, on the basis of relative performance. We propose a theory for, and study experimentally, the phenomenon of fatigue in a dynamic competitive environment. We find that subjects react strongly to changes in the environment related to fatigue and follow the comparative statics of equilibrium predictions. At the same time, within a given environment, subjects behave as if they are unaware of the deteriorating effect of fatigue on their competitiveness.
Compacting XML data

Compression aims to reduce the size of data without loss of information. Compaction is a special kind of compression in which the output is in the same language as the input. Compaction of an XML data forest produces a smaller XML forest, without losing any data. This paper develops a formal framework for the compaction of XML data and presents two compaction techniques.
Statistics of Dark Matter Substructure: II. Comparison of Model with Simulation Results

We compare subhalo mass and velocity functions obtained from different simulations with different subhalo finders among each other, and with predictions from the new semi-analytical model of Jiang & van den Bosch (2014). We find that subhalo mass functions (SHMFs) obtained using different subhalo finders agree with each other at the level of � 20 percent, but only at the low mass end. At the massive end, subhalo finders that identify subhaloes based purely on density in configuration space dramatically underpredict the subhalo abundances by more than an order of magnitude. These problems are much less severe for subhalo velocity functions (SHVFs), indicating that they arise from issues related to assigning masses to the subhaloes, rather than from detecting them. Overall the predictions from the semi-analytical model are in excellent agreement with simulation results obtained using the more advanced subhalo finders that use information in six dimensional phase-space. In particular, the model accurately reproduces the slope and host-mass-dependent normalization of both the subhalo mass and velocity functions. We find that the SHMFs and SHVFs have power-law slopes of 0.82 and 2.6, respectively, significantly shallower than what has been claimed in several studies in the literature.
Blind estimation of direct sequence spread spectrum signals in multipath

Self-recovering receivers for direct-sequence spread-spectrum signals with unknown spreading codes are discussed in this paper. Applications include signal interception, jamming, and low probability of intercept (LPI) communications. A multirate/multichannel, discrete-time model of the spread spectrum signal is introduced, which establishes links with array processing techniques. Borrowing blind channel estimation ideas, which were originally developed in the context of fractionally spaced equalizers or receivers with multiple antennas, linear solutions are obtained that are independent of the input distribution. The signal interception problem is further studied, and a zero-forcing (ZF) receiver/equalizer is proposed to recover the transmitted data. Its performance is analyzed, and some illustrative simulations are presented.
A CMOS channel-select filter for a direct-conversion wireless receiver

A highly selective and linear switched-capacitor channel-select filter is fabricated in 1-/spl mu/m CMOS for a direct-conversion wireless receiver operating in the 902-928 MHz ISM band. The filter selects a 230-kHz wide channel and attenuates by at least 50 dB from 320 kHz to 57 MHz. The input IP3 is +30 dBm, the input-referred noise in the passband is 70 nV//spl radic/Hz, and the circuit takes 4.6 mA from a 3.3 V supply. Direct subsampling of the 915 MHz RF input signal by the filter front-end is also demonstrated with only a small degradation in linearity. The input noise voltage is halved in a redesign while keeping the current drain unchanged.
Balancing performance, robustness and flexibility in routing systems

Modern networks face the challenging task of handling increasingly diverse traffic that is displaying a growing intolerance to disruptions. This has given rise to many initiatives, and in this paper we focus on multiple topology routing as the primary vehicle for meeting those demands. Specifically, we seek routing solutions capable of not just accommodating different performance goals, but also preserving them in the presence of disruptions. The main challenge is computational, i.e., to identify among the enormous number of possible routing solutions the one that yields the best compromise between performance and robustness. This is where our principal contribution lies, as we expand the definition of critical links - a key concept in improving the efficiency of routing computation - and develop a precise methodology to efficiently converge on those solutions. Using this new methodology, we demonstrate that one can compute routing solutions that are both flexible in accommodating different performance requirements and robust in maintaining them in the presence of failures and traffic fluctuations.
Perceived Parental Activity of Mothers, Fathers, and Grandmothers in Three-Generational Black Families:

Grandmothers, mothers, fathers, and children between the ages of 8-14 reported their perceptions of adult childrearing activities. For the 60 participating families, there were two levels of family structure, single-parent or dual-parent, two levels of grandmother's domicile, living with the family or living in the local community, and the sex of the child. The results indicated grandmothers perceived themselves and were perceived as having more active involvement with children when they lived with their single adult daughter than in the other conditions. Also fathers of sons were perceived as more involved with their children than were the fathers of daughters. Generally, these findings indicated that Black family patterns are more complex than previously assumed.
Scheduling Partition for Order Optimal Capacity in Large-Scale Wireless Networks

The capacity scaling property specifies the change of network throughput when network size increases. It serves as an essential performance metric in large-scale wireless networks. Existing results have been obtained based on the assumption of using a globally planned link transmission schedule in the network, which is however not feasible in large wireless networks due to the scheduling complexity. The gap between the well-known capacity results and the infeasible assumption on link scheduling potentially undermines our understanding of the achievable network capacity. In this paper, we propose the scheduling partition methodology that decomposes a large network into small autonomous scheduling zones and implements a localized scheduling algorithm independently in each partition. We prove the sufficient and the necessary conditions for the scheduling partition approach to achieve the same order of capacity as the widely assumed global scheduling strategy. In comparison to the network dimension √(n), scheduling partition size n Θ(r(n)) is sufficient to obtain the optimal capacity scaling, where r(n) is the node transmission radius and much smaller than √(n). We n finally propose a distributed partition protocol and a localized scheduling algorithm as our scheduling solution for maximum capacity in large wireless networks.
Are M-atrix theory and Maldacena's conjecture related?

Abstract We give arguments in the support of a relation between M-atrix theory and Maldacena's conjecture. M-atrix theory conjecture implies the equivalence of 11-D light-cone supergravity and strongly-coupled (0 + 1)-D SYM. Maldacena's SUGRA/SYM duality conjecture implies, in the one dimensional SYM case, the equivalence between strongly-coupled (0 + 1)-D SYM and 11-D supergravity compactified on a spatial circle in the formal Seiberg-Sen limit. Using the classical equivalence between 11-D supergravity on a light-like circle and on a spatial circle in the formal Seiberg-Sen limit, we argue that in the (0 + 1)-D SYM case, the large-N M-atrix theory in the supergravity regime is equivalent to SUGRA/SYM duality.
A study of the microwave sounding unit on the NOAA-12 satellite

The microwave sounding unit (MSU) on the NOAA series of polar-orbiting environmental satellites is a four-channel Dicke radiometer making passive measurements with the channels centered at 50.30, 53.74, 54.96, and 57.95 GHz, respectively. Onboard blackbody and cold space calibrations are performed once every 25.6 seconds for each scan line. The MSU data are extensively used for atmospheric temperature retrieval and climatological studies. After the launch of the NOAA-12 satellite on May 14, 1991, it was observed that the system gain in channel 2 decreased by approximately a factor of 2 from its pre-launch value and that it required a special correction to the pre-launch calibration coefficients for channel 2. Recently, it was discovered that the pre-launch calibration coefficients may be inaccurate because of an error found in the MSU manufacturer's computer software that has used to process the thermal-vacuum chamber test data for the pre-launch calibration. In this study, the author reprocessed the pre-launch calibration data and obtained a new set of nonlinearity coefficients, which can be used to generate more accurately the atmospheric brightness temperatures. The author also examined some in-orbit MSU data, particularly, the blackbody and cold space counts used for onboard calibrations. In addition, the in-orbit variation of the temperatures of the Dicke loads and the blackbody targets monitored by the platinum resistance thermometers (PRT's) was also investigated. This provides us a better understanding of the MSU in-orbit data. Test cases show that antenna temperatures generated from the new nonlinearity coefficients can be 0.5 K lower than the current operationally retrieved atmospheric temperatures. Alternative calibration algorithms for modeling the MSU nonlinear contributions are also explored. Calculated results show that the antenna temperatures will be further reduced if the alternative calibration algorithms are employed. The results from this study may be used to improve the accuracy of temperature retrievals from the NOAA-12 MSU data. >
The Reaction of Hydrazine with α‐Cyanocinnamate Esters: A Caveat

Abstract α‐Cyanocinnamate esters react with hydrazine to give initial products of conjugate addition that then undergo a fragmentation to give the azine of the carbonyl precursor to the starting ester, rather than intramolecular aminolysis to give the pyrazolidinone.
Robust output feedback model predictive control using off-line linear matrix inequalities

Abstract A fundamental question about model predictive control (MPC) is its robustness to model uncertainty. In this paper, we present a robust constrained output feedback MPC algorithm that can stabilize plants with both polytopic uncertainty and norm-bound uncertainty. The design procedure involves off-line design of a robust constrained state feedback MPC law and a state estimator using linear matrix inequalities (LMIs). Since we employ an off-line approach for the controller design which gives a sequence of explicit control laws, we are able to analyze the robust stabilizability of the combined control laws and estimator, and by adjusting the design parameters, guarantee robust stability of the closed-loop system in the presence of constraints. The algorithm is illustrated with two examples.
Measurements of Protein-Protein Interactions by Size Exclusion Chromatography

A method is presented for determining second virial coefficients (B2) of protein solutions from retention time measurements in size exclusion chromatography. We determine B2 by analyzing the concentration dependence of the chromatographic partition coefficient. We show the ability of this method to track the evolution of B2 from positive to negative values in lysozyme and bovine serum albumin solutions. Our size exclusion chromatography results agree quantitatively with data obtained by light scattering. 1980) allows one to fix the solute concentration in the column directly, it requires a large amount of protein (;0.5 g) and long experiment times (;3 h per column run). In this study, we extend their method to pulse size exclusion high- performance liquid chromatography (HPLC), where a small amount of protein is injected into and subsequently flows down the column. This adaptation drastically reduces the amount of protein (\25 mg) and time needed (;15 min per column run) to measure B2 by SEC. We show that our results for B2 obtained with size exclusion chromatography agree well with those from frontal chromatography and from light- scattering measurements. We also demonstrate that SEC can track the evolution of B2 from positive to negative values.
A Primal-Dual Formulation for Certifiable Computations in Schubert Calculus

Formulating a Schubert problem as solutions to a system of equations in either Plucker space or local coordinates of a Schubert cell typically involves more equations than variables. We present a novel primal-dual formulation of any Schubert problem on a Grassmannian or flag manifold as a system of bilinear equations with the same number of equations as variables. This formulation enables numerical computations in the Schubert calculus to be certified using algorithms based on Smale's $$\alpha $$ź-theory.
EXCITATION OF ORBITAL ECCENTRICITIES BY REPEATED RESONANCE CROSSINGS: REQUIREMENTS

Divergent migration of planets within a viscous circumstellar disk can engender resonance crossings and dramatic excitation of orbital eccentricities. We provide quantitative criteria for the viability of this mechanism. For the orbits of two bodies to diverge, a ring of viscous material must be shepherded between them. As the ring diffuses in radius by virtue of its intrinsic viscosity, the two planets are wedged farther apart. The ring mass must be smaller than the planetary masses so that the crossing of an individual resonance lasts longer than the resonant libration period. At the same time, the resonance crossing cannot be of such long duration that the disk’s direct influence on the bodies’ eccentricities interferes with the resonant interaction between the two planets. This last criterion is robustly satisfied because resonant widths are typically tiny fractions of the orbital radius. We evaluate our criteria not only for giant planets within gaseous protoplanetary disks but also for shepherd moons that bracket narrow planetary rings in the solar system. A shepherded ring of gas orbiting at a distance of 1 AU from a solar-type star and having a surface density of less than 500 gc m � 2 , a dimensionless alpha viscosity of 0.1, and a height-to-radius aspect ratio of 0.05 can drive two Jupiter-mass planets through the 2 : 1 and higher order resonances so that their eccentricities amplify to values of several tenths. Because of the requirement that the disk mass in the vicinity of the planets be smaller than the planet masses, divergent resonance crossings may figure significantly into the orbital evolution of planets during the later stages of protoplanetary disk evolution, including the debris disk phase. Subject headings: accretion, accretion disks — celestial mechanics — planetary systems — planets and satellites: individual (Uranus, Epsilon ring)
Estimating Equilibrium Models Of Sorting Across Locations

While there is growing interest in measuring the size and scope of local spillovers, it is well understood that such spillovers cannot be distinguished from unobservable local attributes using solely the observed location decisions of individuals or firms. We propose an empirical strategy for recovering estimates of spillovers in the presence of unobserved local attributes for a broadly applicable class of equilibrium sorting models. Our approach relies on an IV strategy derived from the internal logic of the sorting model itself. We show practically how the strategy is implemented, provide intuition for our instruments, discuss the role of effective choice-set variation in identifying the model, and carry-out a series of Monte Carlo simulations to demonstrate performance in small samples.
A note on dimensions of polynomial size circuits

In this paper, we use resource-bounded dimension theory to investigate polynomial size circuits. We show that for every i ≥0, P/poly has ith-order scaled p3-strong dimension 0. We also show that P/polyi.o. has p3-dimension 1/2 and p3-strong dimension 1. Our results improve previous measure results of Lutz [Almost everywhere high nonuniform complexity, J. Comput. Syst. Sci. 44(2) (1992) 220-258] and dimension results of Hitchcock and Vinodchandran [Dimension, entropy rates, and compression, in: Proc. 19th IEEE Conf. Computational Complexity, 2004, pp. 174-183, J. Comput. Syst. Sci., to appear]. Additionally, we establish a Supergale Dilation Theorem, which extends the martingale dilation technique introduced implicitly by Ambos-Spies, Terwijn, and Zheng [Resource bounded randomness and weakly complete problems, Theoret. Comput. Sci. 172(1-2)(1997) 195-207] and made explicit by Juedes and Lutz [Weak completeness in E and E2, Theoret. Comput. Sci. 143(1) (1995) 149-158].
Maximizing remote work in flooding-based peer-to-peer systems

In peer-to-peer (P2P) systems where individual peers must cooperate to process each other's requests, a useful metric for evaluating the system is how many remote requests are serviced by each peer. In this paper, we apply this remote work metric to study the searching aspect of flooding-based P2P networks such as Gnutella. We study how to maximize the remote work (query) in the entire network by controlling the rate of query injection at each node. In particular, we provide a simple procedure for finding the optimal rate of query injection and prove its optimality. We also show that a simple prefer-high-TTL protocol in which each peer processes only queries with the highest time-to-live (TTL) is optimal.
A queueing approach to manufacturing flow control models

Presents a new method developed to study the problem of optimal production control in failure prone manufacturing systems. The key idea of the method is to explore a relationship of the failure prone manufacturing systems to some simple queueing systems. By using this relationship the author can easily evaluate cost functions based on existing results in queueing theory and some simple level crossing techniques. In addition to its simplicity, the method is applicable to non-Markovian systems while previous methods are mainly limited to Markovian systems. Several examples are provided to illustrate the basic idea of the method and to which systems it may be applied.
Bio-inspired unmanned undersea vehicle

Biological systems in ocean environment provide all the desired features required for design of unmanned undersea vehicles. We noticed the uniqueness and simplicity in the design of rowing medusa and have successfully demonstrated working prototypes of Aurelia Aurita. In this study, we demonstrate the effect of bell joints in reducing the contraction force required for deformation. The study is based on observations made for the sub-umbrella features of jellyfish. Artificial jellyfish unmanned undersea vehicle (UUV) was fabricated consisting of silicone as the matrix material and shape memory alloy (SMA) as the actuation material. UUV was characterized for its performance and tailored to achieve vertical motion. SMAs were selected for actuation material because they are simple current-driven device providing large strain and blocking force. However, electrical power requirements were found to be quite high in the underwater conditions. It was identified that by including "joints" in the structural material forming the bell, the overall power requirement can be reduced as it lowers the resistance to compression. An analytical model was developed that correlates the deformation achieved with the morphology of the joints. Experiments were conducted to characterize the effect of both joint shapes and structural materials on the motion. Results are compared with that of natural medusa gastrodermal lamella and analyzed using the theoretical model. By including the features inherently present in natural jellyfish, the required compression force was found to be decreased.
The role of semiconductor device diameter and energy-band bending in convergence of Picard iteration for Gummel's map

Steady-state semiconductor-device simulation is studied. A mathematical analysis of the so-called Lipschitz constant of the Gummel map, in the Slotboom variables, is given in terms of the device diameter d and the band-bending. This constant is directly related to the convergence of Picard iteration, within a convex, compact solution set, determined by the steady state, Van Roosbroeck system maximum principles. Allowing for specified gradient singularities, of order cr^{-1/2} we obtain an asymptotic dependence of d^{5/2} as d \rightarrow 0 . Functions of sup-inf boundary values of the data also appear, particularly as related to doping concentrations, in the representation of the band-bending. For simplicity, constant mobilities and zero recombination are assumed, at thermodynamic equilibrium. The setting is general, but motivated by FET devices. For micron devices at room temperature, convergence and unique solutions are expected up to, perhaps, band-bending of 0.42 - ⅔ \log c(kT) electronvolts in width across the intrinsic energy level. The definition of the Gummel map used herein employs the potential equation as a fractional step, based upon given values of the Slotboom variables. The continuity equations are then solved for the values associated with the Gummel map. The condition given for convergence of Picard iteration also guarantees uniqueness of solutions of the device model for prescribed doping and contact conditions. Finally, the constant c is estimated on the basis of heuristic considerations.
Thermodynamically Stable Conducting Films of Intermetallic PtGa2 on Gallium Arsenide

Abstract : The first epitaxial platinum gallium two (PtGa2) films have been grown on gallium arsenide (GaAs)(100) by co-evaporation of the elements under ultra-high vacuum conditions. An electron-beam evaporator and a Knudsen cell were used to produce the platinum and gallium beams, respectively. The resulting films and bulk PtGa2 have been characterized by x-ray diffraction, Auger electron spectroscopy, and x-ray photoelectron spectroscopy. The data confirm the PtGa2 stoichiometry and crystal structure of the films, and demonstrate their chemical stability on GaAs(100). This study supports the contention that PtGa2 can be a suitable, temperature-stable contact material on GaAs substrates. Epitaxial films; Ultra-high vacuum; Chemical stability; Compound semiconductors; Contact degradation; Schottky barrier; Fermi level pinning.
Electrical resistance: an atomistic view

This tutorial article presents a 'bottom-up' view of electrical resistance starting from something really small, like a molecule, and then discussing the issues that arise as we move to bigger conductors. Remarkably, no serious quantum mechanics is needed to understand electrical conduction through something really small, except for unusual things like the Kondo effect that are seen only for a special range of parameters. This article starts with energy level diagrams (section 2), shows that the broadening that accompanies coupling limits the conductance to a maximum of q2/h per level (sections 3, 4), describes how a change in the shape of the self-consistent potential profile can turn a symmetric current–voltage characteristic into a rectifying one (sections 5, 6), shows that many interesting effects in molecular electronics can be understood in terms of a simple model (section 7), introduces the non-equilibrium Green function (NEGF) formalism as a sophisticated version of this simple model with ordinary numbers replaced by appropriate matrices (section 8) and ends with a personal view of unsolved problems in the field of nanoscale electron transport (section 9). Appendix A discusses the Coulomb blockade regime of transport, while appendix B presents a formal derivation of the NEGF equations. MATLAB codes for numerical examples are listed in appendix C. (The appendices are available in the online version only.)
The Maximum B-mode Polarization of the Cosmic Microwave Background from Inhomogeneous Reionization

We compute the B-mode polarization power spectrum of the CMB from an epoch of inhomogeneous reionization, using a simple model in which H II regions are represented by ionized spherical bubbles with a log normal distribution of sizes whose clustering properties are determined by large-scale structure. Both the global ionization fraction and the characteristic radius of H II regions are allowed to be free functions of redshift. Models that would produce substantial contamination to degree scale gravitational wave B-mode measurements have power that is dominated by the shot noise of the bubbles. Rare bubbles of & 100 Mpc at z > 20 can produce signals that in fact exceed the B-modes from gravitational lensing and are comparable to the maximal allowed signal of gravitational waves (∼ 0.1 � K) while still being consistent with global constraints on the total optical depth. Even bubbles down to 20 Mpc at z ∼ 15, or 40 Mpc at z ∼ 10 can be relevant (0.01 � K) once the lensing signal is removed either statistically or directly. However, currently favored theoretical models that have ionization bubbles that only grow to such sizes at the very end of a fairly prompt and late reionization produce signals which are at most at these levels. Subject headings: cosmic microwave background — cosmology: theory — large-scale structure of universe
DO EXTRAGALACTIC COSMIC RAYS INDUCE CYCLES IN FOSSIL DIVERSITY

Recent work has revealed a 62 ± 3 Myr cycle in fossil diversity in the past 542 Myr; however, no plausible mechanism has been found. We propose that the cycle may be caused by modulation of cosmic-ray (CR) flux by the solar system vertical oscillation (64 Myr period) in the Galaxy, the Galactic north-south anisotropy of CR production in the Galactic halo/wind/termination shock (due to the Galactic motion toward the Virgo Cluster), and the shielding by Galactic magnetic fields. We revisit the mechanism of CR propagation and show that CR flux can vary by a factor of about 4.6 and reach a maximum at northernmost displacement of the Sun. The very high statistical significance of (1) the phase agreement between solar northward excursions and the diversity minima and (2) the correlation of the magnitude of diversity drops with CR amplitudes through all cycles provide solid support for our model. Various observational predictions which can be used to confirm or falsify our hypothesis are presented.
Off-farm labor supply responses to permanent and transitory farm income

A sample of Iowa farm couples is used to evaluate whether off-farm labor supply decisions respond to permanent and transitory components of farm income. Off-farm labor supply of both spouses declines in response to increases in permanent farm income. Farm wives also reduce off-farm labor supply in response to positive transitory farm income shocks. Consequently, one mechanism farm households use to smooth their goods consumption when facing fluctuating farm income is to modify their consumption of leisure. Ability to smooth goods consumption does not imply the absence of liquidity constraints among farm households unless leisure consumption is also smoothed.
Mild conditions for Pd-catalyzed carboamination of N-protected hex-4-enylamines and 1-, 3-, and 4-substituted pent-4-enylamines. Scope, limitations, and mechanism of pyrrolidine formation.

The use of the weak base Cs2CO3 in Pd-catalyzed carboamination reactions of N-protected γ-aminoalkenes with aryl bromides leads to greatly increased tolerance of functional groups and alkene substitution. Substrates derived from (E)- or (Z)-hex-4-enylamines are stereospecifically converted to 2,1′-disubstituted pyrrolidine products that result from suprafacial addition of the nitrogen atom and the aryl group across the alkene. Transformations of 4-substituted pent-4-enylamine derivatives proceed in high yield to afford 2,2-disubstituted products, and cis-2,5- or trans-2,3-disubstituted pyrrolidines are generated in good yield with excellent diastereoselectivity from N-protected pent-4-enylamines bearing substituents at C1 or C3. The reactions tolerate a broad array of functional groups, including esters, nitro groups, and enolizable ketones. The scope and limitations of these transformations are described in detail, along with models that account for the observed product stereochemistry. In addition, deut...
Focal plane optics in far-infrared and submillimeter astronomy

The construction of airborne observatories, high mountaintop observatories, and space observatories designed especially for infrared and submillimeter astronomy has opened fields of research requiring new optical techniques. A typical far-IR photometric study involves measurement of a continuous spectrum in several passbands between ~30 µm and 1000 µm and diffraction-limited mapping of the source. At these wavelengths, diffraction effects strongly influence the design of the field optics systems that couple the incoming flux to the radiation sensors (cold bolometers). The Airy diffraction disk for a typical telescope at submillimeter wavelengths (~100 um to 1000 um) is many millimeters in diameter; the size of the field stop must be comparable. The dilute radiation at the stop is fed through a Winston nonimaging concentrator to a small cavity containing the bolometer. The purpose of this paper is to review the principles and techniques of infrared field optics systems, including spectral filters, concentrators, cavities, and bolometers (as optical elements), with emphasis on photometric systems for wavelengths longer than 60 µm.
Arc control devices for use on all-dielectric self-supporting, optical cables

All-dielectric, self-supporting, optical cables can suffer from damage caused by dry-band arcing. This problem only occurs when the cables are strung on power lines whose system voltages are in excess of 150 kV, in areas which are subject to pollution which is conducting when wet, for example saline pollution. It is the aim of the paper to promote discussion, by proposing and subjecting to preliminary examination several devices which may be able to control the arcing which causes the damage. It is concluded that the study of such devices is worth pursuing.
A one-flask synthesis of α,α-bisphosphonates via enolate chemistry

Treatment of several carbonyl compounds with excess strong base and diethyl phosphorochloridite results in formation of two carbonphosphorus bonds at the α carbon. Oxidation of the immediate product with H2O2 affords the corresponding α,α-bisphosphonate in moderate to very good yields.
Brocaenols A−C: Novel Polyketides from a Marine-Derived Penicillium brocae

Chemical investigation of a Penicillium brocae, obtained from a tissue sample of a Fijian Zyzyya sp. sponge, yielded two known diketopiperazines and three novel cytotoxic polyketides, brocaenols A-C. The brocaenols contain an unusual enolized oxepine lactone ring system that to the best of our knowledge is unprecedented in the literature. The structures were elucidated by using 2D-NMR methods including an INADEQUATE experiment. The absolute stereochemistry of brocaenol A was established by using a modified Mosher method. The taxonomy of the producing fungus was elucidated by using both morphological and rDNA sequence analysis.
The effects of teacher social presence on student satisfaction, engagement, and learning

This research experimentally manipulated the social presence cues in instructor's messages to students. The context was an online professional development one credit course with 1:1 mentoring of students. Additionally, student learning goals, beliefs about learning, and levels of trust were examined as factors that may mitigate the effects of social presence. Results indicate that social presence affects the learner's interactions and perception of the mentor but has no effect on perceived learning, satisfaction, engagement, or the quality of their final course product. These findings suggest social presence is a correlational rather than a causal variable associated with student learning. Exploratory analyses suggest no effect of student learning goals, but that trust is associated with performance.
A Characterization of Cybersecurity Posture from Network Telescope Data

Data-driven understanding of cybersecurity posture is an important problem that has not been adequately explored. In this paper, we analyze some real data collected by CAIDA's network telescope during the month of March 2013. We propose to formalize the concept of cybersecurity posture from the perspectives of three kinds of time series: the number of victims i.e., telescope IP addresses that are attacked, the number of attackers that are observed by the telescope, and the number of attacks that are observed by the telescope. Characterizing cybersecurity posture therefore becomes investigating the phenomena and statistical properties exhibited by these time series, and explaining their cybersecurity meanings. For example, we propose the concept of sweep-time, and show that sweep-time should be modeled by stochastic process, rather than random variable. We report that the number of attackers and attacks from a certain country dominates the total number of attackers and attacks that are observed by the telescope. We also show that substantially smaller network telescopes might not be as useful as a large telescope.
Real and financial crises in the Keynes–Kalecki structuralist model: An agent‐based approach

Agent-based models are inherently microstructures—with their attention to agent behavior in a field context—and only aggregate up to systems with recognizable macroeconomic characteristics. One might ask why the traditional Keynes–Kalecki or structuralist (KKS) model would bear any relationship to the multi-agent modeling approach. This paper shows how KKS models might benefit from agent-based microfoundations, without sacrificing traditional macroeconomic themes, such as aggregate demand, animal spirits and endogenous money. Above all, the integration of the two approaches gives rise to the possibility that a KKS system—stable over many consecutive time periods—might lurch into an uncontrollable downturn, from which a recovery would require outside intervention. As a by-product of the integration of these two popular approaches, there emerges a cogent analysis of the network structure necessary to bind real and financial agents into an integrated whole. It is seen, contrary to much of the existing literature, that a highly connected financial system does not necessarily lead to more crashes of the integrated system.
Number and distribution of human hemic cells.

1. Methods are described which make possible the calculation of the number and distribution of the hemic cells of the body. 2. The numbers of these cells in the various blood-forming organs, in the blood outside these areas, and in the total body are summarized in table 3, together with the ratios of the number in the blood to the number outside the hematopoietic organs for the standard 70 Kg. human male. Dividing these figures by 70 will give the values per Kg. 3. By similar methods the values for other age and sex groups in man and for other species may be calculated. 4. Leukocytes apparently are not primarily blood cells but are merely en route in the blood to the defense of body tissue generally. Only 1/40 to 1/400 of the total leukocytes outside the hematopoietic organs are present in the blood stream at any one time. 5. These somewhat surprising figures account for many previously made observations which were hitherto hard to explain.
Data aggregators, consumer data, and responsibility online: Who is tracking consumers online and should they stop?

The goal of this article is to examine the strategic choices of firms collecting consumer data online and to identify the roles and obligations of the actors within the current network of online tracking. In doing so, the focus shifts from placing the onus on individuals to make an informed choice, to justifying the roles and responsibilities of firms when gathering, aggregating, and using consumers' interests or behavior online. Firms online are uniquely positioned to undercut or to respect privacy expectations within three possible roles: as a member of a supply chain of information traders, within a network of surveillance online, and as an arm of law enforcement. These firms benefit from aggregating and analyzing consumer data and have an associated responsibility to not only minimize the harm to consumers but also to enact change where the firm is in the most knowledgeable and powerful position.
The relationship between plasma lipid peroxidation products and primary graft dysfunction after lung transplantation is modified by donor smoking and reperfusion hyperoxia.

Background Donor smoking history and higher fraction of inspired oxygen (Fio 2 ) at reperfusion are associated with primary graft dysfunction (PGD) after lung transplantation. We hypothesized that oxidative injury biomarkers would be elevated in PGD, with higher levels associated with donor exposure to cigarette smoke and recipient hyperoxia at reperfusion. Methods We performed a nested case-control study of 72 lung transplant recipients from the Lung Transplant Outcomes Group cohort. Using mass spectroscopy, F 2 -isoprostanes and isofurans were measured in plasma collected after transplantation. Cases were defined in 2 ways: grade 3 PGD present at day 2 or day 3 after reperfusion (severe PGD) or any grade 3 PGD (any PGD). Results There were 31 severe PGD cases with 41 controls and 35 any PGD cases with 37 controls. Plasma F 2 -isoprostane levels were higher in severe PGD cases compared with controls (28.6 pg/ml vs 19.8 pg/ml, p = 0.03). Plasma F 2 -isoprostane levels were higher in severe PGD cases compared with controls (29.6 pg/ml vs 19.0 pg/ml, p = 0.03) among patients reperfused with Fio 2 >40%. Among recipients of lungs from donors with smoke exposure, plasma F 2 -isoprostane (38.2 pg/ml vs 22.5 pg/ml, p = 0.046) and isofuran (66.9 pg/ml vs 34.6 pg/ml, p = 0.046) levels were higher in severe PGD compared with control subjects. Conclusions Plasma levels of lipid peroxidation products are higher in patients with severe PGD, in recipients of lungs from donors with smoke exposure, and in recipients exposed to higher Fio 2 at reperfusion. Oxidative injury is an important mechanism of PGD and may be magnified by donor exposure to cigarette smoke and hyperoxia at reperfusion.
Detecting Large-Scale System Problems by Mining Console Logs

Surprisingly, console logs rarely help operators detect problems in large-scale datacenter services, for they often consist of the voluminous intermixing of messages from many software components written by independent developers. We propose a general methodology to mine this rich source of information to automatically detect system runtime problems. We use a combination of program analysis and information retrieval techniques to transform free-text console logs into numerical features, which captures sequences of events in the system. We then analyze these features using machine learning to detect operational problems. We also show how to distill the results of our analysis to an operator-friendly one-page decision tree showing the critical messages associated with the detected problems. In addition, we extend our methods to online problem detection where the sequences of events are continuously generated as data streams.
Functionalization of C(sp3)–H bonds using a transient directing group

Proximity-driven metalation has been extensively exploited to achieve reactivity and selectivity in carbon–hydrogen (C–H) bond activation. Despite the substantial improvement in developing more efficient and practical directing groups, their stoichiometric installation and removal limit efficiency and, often, applicability as well. Here we report the development of an amino acid reagent that reversibly reacts with aldehydes and ketones in situ via imine formation to serve as a transient directing group for activation of inert C–H bonds. Arylation of a wide range of aldehydes and ketones at the β or γ positions proceeds in the presence of a palladium catalyst and a catalytic amount of amino acid. The feasibility of achieving enantioselective C–H activation reactions using a chiral amino acid as the transient directing group is also demonstrated.
An Equilibrium Analysis of Scrip Systems

A game-theoretic model of scrip (artificial currency) systems is analyzed. It is shown that relative entropy can be used to characterize the distribution of agent wealth when all agents use threshold strategies—that is, they volunteer to do work if and only if they have below a threshold amount of money. Monotonicity of agents' best-reply functions is used to show that scrip systems have pure strategy equilibria where all agents use threshold strategies. An algorithm is given that can compute such an equilibrium and the resulting distribution of wealth.
Crime and labour market turnover

ABSTRACTWe go beyond unemployment to investigate how its determinants, specifically hires, lay-offs and quits, affect crime. As expected, we find less crime in localities with higher hiring and quit rates and lower lay-off rates. The size of relationships is on the order of studies analysing the link between unemployment and crime.
Individual Tax Rates and Regional Tax Revenues: A Cross-State Analysis

ABSTRACTIndividual tax rates and regional tax revenues: a cross-state analysis. Regional Studies. This paper analyzes the effects of state-level personal tax rates on state tax revenue and individual welfare. The policy analysis based on a general equilibrium model suggests that tax revenues would benefit from higher wage–income, sales or property taxes, while any increase in dividend–income tax would result in a reduction of revenues. It is also shown that individuals would suffer from an increase in state-level wage–income tax, dividend tax or sales tax, while they would benefit from an increase in property taxes. The heterogeneity across states is determined by a TaxIndex, a weighted average of initial taxes at the state level.