cssi/SciSciGPT-SciSciNet huggingface dataset:
General Strategy for Zero-Valent Intercalation into Two-Dimensional Layered Nanomaterials

We demonstrate the complete tunability of a general strategy to intercalate zero-valent atoms into two-dimensional (2D) layered materials. A chemical method was used to intercalate high densities of copper (up to 55 atomic percent) into synthesized nanomaterials such as MoO3, Sb2Te3, In2Se3, and GaSe. These materials were characterized using TEM, EDX, electron diffraction, XRD, Raman, EELS, and XPS to observe the effects of intercalation, determine the concentration of copper, and confirm the zero-valent nature of the intercalant as well as unchanged structure of the host material. This technique reveals the power and potential to observe unique chemical and physical phenomena and to control such properties for particular applications.
Waveform measurements in high-speed silicon bipolar circuits using a picosecond photoelectron scanning electron microscope

A description is given of a noncontact waveform measurement technique for the characterization of high-speed LSI and VLSI circuits using a picosecond photoelectron scanning electron microscope with 5-ps temporal resolution, 0.1- mu m spatial resolution, and a voltage resolution of 3 mV/ square root Hz. The ability of the technique to measure and monitor the internal waveforms and to resolve the different contributions of the delay in the circuit without any loading effect is demonstrated by its application to the full characterization of sub-100-ps silicon bipolar ECL (emitter-coupled logic) circuits. >
Clinical Characteristics and Biopsy Specimen Features in African-American and White Men Without Prostate Cancer

Background: The reported incidence of prostate cancer is higher among African-American men than among white men. We conducted a study of African-American and white men without prostate cancer to determine whether clinical and histologic findings might be associated with racial differences in serum prostate-specific antigen (PSA) levels. Methods: From January 1990 through March 1997, 493 (59.5%) of 829 African-American men and 736 (74.1%) of 993 white men who had elevated serum PSA levels (>4.0 ng/mL) and/or abnormal digital rectal examinations and who underwent transrectal ultrasound-guided prostate biopsies were found to be without prostate cancer. Also reviewed were patients’ age and race, indication for biopsy, histologic features of the prostate biopsy specimen, ultrasound-measured prostate volume, PSA density (i.e., the PSA level divided by the prostate volume), and (in some cases) serum testosterone levels. Results: Among these men without prostate cancer, there were no statistically significant differences by race in the ages of the patients, their prostate volumes, or their serum testosterone levels; however, the mean serum PSA levels and PSA densities were significantly higher in African-American men than in white men (twosided P values of .00003 and .000009, respectively). A higher proportion of African-American men than white men had inflammation in their prostate biopsy specimen, and men of both races with prostate inflammation had higher PSA values than those without inflammation. African-American men without inflammation had higher PSA values than white men without inflammation. Conclusions: In this study, African-American men without histologic evidence of prostate cancer had significantly higher PSA levels and PSA densities than similarly aged white men. This finding was not accounted for by racial differences in patients’ age, serum testosterone level, or prostate volume. [J Natl Cancer Inst 1998;90:756‐60]
Reconstruction of turbulence-degraded images using the vector Wiener filter

Adaptive optics and speckle imaging are common methods for improving Fourier domain signal-to-noise ratio (SNR) in astronomical images. These techniques may benefit from linear processing to decon- volve blurring due to the attenuation of high spatial frequencies in the compensated images. Typical linear deconvolution methods require an explicit estimate of the random atmospheric-optical system point spread function or optical transfer function (OTF). In addition, a priori knowledge of the object class and noise are not used in an optimal manner. We apply a vector Wiener filter to photon-limited images degraded by atmo- spheric turbulence to demonstrate the potential advantages of optimal deconvolution processing. This filter incorporates model-based informa- tion about object, OTF, and noise. To our knowledge, this is the first application of complete OTF correlation statistics to the reconstruction of turbulence-degraded images. Computer simulation of binary star images show the vector Wiener filter provides superior reconstructions when compared to the traditional scalar Wiener filter for non-wide-sense sta- tionary objects. Much of this performance improvement can be attributed to variance reduction in the noisy Fourier data at spatial frequencies where the mean OTF is severely attenuated. However, vector Wiener filter performance is substantially degraded with respect to both mean square error and mean square phase error at spatial frequencies where the OTF SNR is less than unity. © 1998 Society of Photo-Optical Instrumentation Engineers. (S0091-3286(98)01009-5)
Starting new team operations: lessons from greenfield managers

Purpose – Greenfields are new plants, typically but not exclusively manufacturing, that belong to an existing organization; as such, they offer an organizational strategy for understanding knowledge transfer. Greenfields are important to understand because they offer advantages for expansion into new economic and labor markets. But the overall challenges starting up a new greenfield cannot be overlooked. The aim of this paper is to try to better understand how knowledge transfer occurs in these interesting team operations.Design/methodology/approach – Plant and human resource managers representing 33 greenfield organizations from food and beverage, consumer products, heavy manufacturing, pharmaceutical and automotive industries were contacted. Managers discuss greenfield rationale, vision, work practices, and business characteristics. Both opportunities and risks are described, along with examples from the research literature.Findings – Greenfields can be successful as experiments in knowledge transfer bu...
Controlled degradation by ClpXP protease tunes the levels of the excision repair protein UvrA to the extent of DNA damage.

UV-irradiation damages DNA and activates expression of genes encoding proteins helpful for survival under DNA stress. These proteins are often deleterious in the absence of DNA damage. Here, we investigate mechanisms used to regulate the levels of DNA-repair proteins during recovery by studying control of the nucleotide excision repair (NER) protein UvrA. We show that UvrA is induced after UV-irradiation and reaches maximum levels between ~20 to 120 min post-UV. During post-UV recovery, UvrA levels decrease principally as a result of ClpXP-dependent protein degradation. The rate of UvrA degradation depends on the amount of unrepaired pyrimidine dimers present; this degradation rate is initially slow shortly after UV, but increases as damage is repaired. This increase in UvrA degradation as repair progresses is also influenced by protein-protein interactions. Genetic and in vitro experiments support the conclusion that UvrA-UvrB interactions antagonize degradation. In contrast, Mfd appears to act as an enhancer of UvrA turnover. Thus, our results reveal that a complex network of interactions contribute to tuning the level of UvrA in the cell in response to the extent of DNA damage and nicely mirror findings with excision repair proteins from eukaryotes, which are controlled by proteolysis in a similar manner.
Working Yourself to Death? The Relationship Between Work Hours and Obesity

Work hours may affect obesity if reduced leisure time decreases exercise and causes substitution from meals prepared at home to fast food and pre-prepared processed food. Additional work by adults may also impact child weight by reducing parental supervision. I find that a rise in work hours increases one's weight and, to a lesser extent, the weight of one's spouse. Mothers', but not fathers', work hours affect child weight. I also find that a rise in work hours is associated with a decrease in exercise and an increase in purchasing food prepared away from home. My estimates imply that changes in labor force participation account for 6% and 10% of the growth in adult and childhood obesity in recent decades.
Folding Flat Crease Patterns With Thick Materials

National Science Foundation (U.S.) (Origami Design for Integration of Self-assembling Systems for Engineering Innovation (ODISSEI Grant No. EFRI-1240383))
A numerical evaluation of global oceanic emissions of α-pinene and isoprene

Abstract. A numerical evaluation of global oceanic emissions of α-pinene and isoprene based on both "bottom-up" and "top-down" methods is presented. We infer that the global "bottom-up" oceanic emissions of α-pinene and isoprene are 0.013 TgC yr−1 and 0.32 TgC yr−1, respectively. By constraining global chemistry model simulations with the shipborne measurement of Organics over the Ocean Modifying Particles in both Hemispheres summer cruise, we derived the global "top-down" oceanic α-pinene source of 29.5 TgC yr−1 and isoprene source of 11.6 TgC yr−1. Both the "bottom-up" and "top-down" values are subject to large uncertainties. The incomplete understanding of the in-situ phytoplankton communities and their range of emission potentials significantly impact the estimated global "bottom-up" oceanic emissions, while the estimated total amounts of the global "top-down" oceanic sources can be influenced by emission parameterizations, model and input data spatial resolutions, boundary layer mixing processes, and the treatments of chemical reactions. The global oceanic α-pinene source and its impact on organic aerosol formation is significant based on "top-down" method, but is negligible based on "bottom-up" approach. Our research highlights the importance of carrying out further research (especially measurements) to resolve the large offset in the derived oceanic organic emission based on two different approaches.
Diffraction Tomography In Layered Background

Diffraction tomography has been investigated mainly with respect to homogeneous background. However, for seismic crosshole surveys carried out in sedimentary environment, layered medium would be the more appropriate background. A diffraction tomography algorithm with respect to layered background is derived by applying the distorted wave Born approximation to the wave solution and by using background solutions appropriate to a layered medium. The formalism employs eigenstates defined with respect to the vertical coordinate for solution and data representation. A 2-D inversion is reduced to a set of independent 1-D inversions. The formalism generalizes previous results with respect to homogeneous background.
Gender, Entrepreneurial Subjectivity, and Pathologies of Personal Finance

This essay examines the constitution of gendered norms for personal financial attitudes and behaviors through the production and circulation of knowledge, especially statistical articulation of populations, across the domains of popular culture, marketing research, and legitimate social science. It thus addresses a nexus of two central features of neoliberalism: governmentality and financialization. It argues that gendered norms play a key role in articulating neoliberal norms more broadly. Specifically, negative, pathologized, portrayals of women as impulsive shopaholics on one hand and paralyzed non-investors on the other indicate the boundaries of responsible entrepreneurial subjectivity. At the same time, these portrayals, found across a range of discursive sites, proffer images of proper femininity and masculinity, to be achieved through the enactment of different configurations of financial attitudes and behaviors. Noting the diversity and internal contradictions implicit in responsible entrepreneurial subjectivity (really, subjectivities), the essay concludes with a consideration of the implications of the current financial crisis and concomitant shifts in the evaluation of gendered behaviors.
Chiral Lagrangian with heavy quark-diquark symmetry

We construct a chiral Lagrangian for doubly heavy baryons and heavy mesons that is invariant under heavy quark-diquark symmetry at leading order and includes the leading O(1/mQ) symmetry violating operators. The theory is used to predict the electromagnetic decay width of the J = 3 member of the ground state doubly heavy baryon doublet. Numerical estimates are provided for doubly charm baryons. We also calculate chiral corrections to doubly heavy baryon masses and strong decay widths of low lying excited doubly heavy baryons.
Some Relationships between the Amino Acid Contents of Proteins and Their Nutritive Values for the Rat

1. The relationship of the amino acid constitution of a protein, or of the protein component of a food product, to its nutritive value for the growing rat can be best revealed, in the absence of accurate values for the amino acid requirements, by computing for each protein, or protein mojety, the percentage deviations of the contents of each essential eamino acid, expressed per 16 gm. of nitrogen, from the corresponding contents of a protein mixture, such as that of whole egg. thart is almost completely digestible by the rat and utilizable in adolescent metabolism. This has been done for a series of twenty-eight proteins and protein mixtures for which satisfactory analyses have been secured for all of the essential amino acids. 2. From such computations, the essential amino acid limiting the nutritive efficiency of the protein will be revealed as that one whose percentage deficit from that of the standard protein (whole egg) is the greatest, due consideration being given to the limiting amino acids thus indicated agree with those determined in feeding experiments with only one or two exceptions. 3. The proteins of foods may be ranked in the order of decreasing nutritive efficiency on the basis of increasing percentage deficits (as above defined) in their respective limiting essential amino acids. These percentage deficits are highly correlated (r = -0.86) with the corresponding biological values determined by the nitrogen metabolism method. Little or no correlation exists between the chemical ratings of th proteins and their digestibility by the growing rat. 4. The biological value of a protein (y) may be roughly estimated from its maximum percentage deficit in an essential amino acid (x) by the equation: = 102 - 0.634x. 5. However, there are known instances in which the biological value of a protein, or protein mixture, and its chemical rating do not agree, for various reasons discussed in the text. 6. In particular, the nutritive value of cereal proteins may be greatly impaired bt the application of heat with no demonstrated alteration in their content of the essential amino acids. 7. A basis for prediciting the effect of heat on the biological value of a food protein is suggested.
Knudsen Effusion Study of the Vaporization of CdO(s)

Knudsen effusion studies were conducted on CdO(s) in fused-SiO2 Knudsen cells from 889 to 1110 K. The orifice size was varied; the largest cell orifice yielded a calculated pressure significantly lower than could be accounted for by experimental error. Average-slope- and average-free-energy-function-based values of ΔHc298 were 86.9 ± 1.1 and 88.8 ± 0.5 kcal/mol, respectively. The data from the present work were combined with those of previous investigators using a method discussed by McCreary and Thorn; a ΔHc298 of 88.2 ± 0.2 kcal/mol was obtained. Using this combined value for ΔHc298 and ΔSc298= 51.40 ± 0.1 eu (obtained from the literature), the equilibrium constant for the reaction CdO(s)= Cd(g)+ 1/2 O2(g) at 900 to 1380 K was calculated to be log K = 10.6-18,800(I/T).
Contextual Online Learning for Multimedia Content Aggregation

The last decade has witnessed a tremendous growth in the volume as well as the diversity of multimedia content generated by a multitude of sources (news agencies, social media, etc.). Faced with a variety of content choices, consumers are exhibiting diverse preferences for content; their preferences often depend on the context in which they consume content as well as various exogenous events. To satisfy the consumers’ demand for such diverse content, multimedia content aggregators (CAs) have emerged which gather content from numerous multimedia sources. A key challenge for such systems is to accurately predict what type of content each of its consumers prefers in a certain context, and adapt these predictions to the evolving consumers’ preferences, contexts, and content characteristics . We propose a novel, distributed, online multimedia content aggregation framework, which gathers content generated by multiple heterogeneous producers to fulfill its consumers’ demand for content. Since both the multimedia content characteristics and the consumers’ preferences and contexts are unknown, the optimal content aggregation strategy is unknown a priori. Our proposed content aggregation algorithm is able to learn online what content to gather and how to match content and users by exploiting similarities between consumer types. We prove bounds for our proposed learning algorithms that guarantee both the accuracy of the predictions as well as the learning speed. Importantly, our algorithms operate efficiently even when feedback from consumers is missing or content and preferences evolve over time. Illustrative results highlight the merits of the proposed content aggregation system in a variety of settings.
Rapid and Efficient Copper-Catalyzed Finkelstein Reaction of (Hetero)Aromatics under Continuous-Flow Conditions†

A general, rapid, and efficient method for the copper-catalyzed Finkelstein reaction of (hetero)aromatics has been developed using continuous flow to generate a variety of aryl iodides. The described method can tolerate a broad spectrum of functional groups, including N-H and O-H groups. Additionally, in lieu of isolation, the aryl iodide solutions were used in two distinct multistep continuous-flow processes (amidation and Mg-I exchange/nucleophilic addition) to demonstrate the flexibility of this method.
Public Announcement Logic in Geometric Frameworks

In this paper, we introduce public announcement logic in different geometric frameworks. First, we consider topological models, and then extend our discussion to a more expressive model, namely, subset space models. Furthermore, we prove the completeness of public announcement logic in those frameworks. After that, we apply our results to different issues: announcement stabilization, backward induction and persistence.
Synthesis of Hindered α-Amino Carbonyls: Copper-Catalyzed Radical Addition with Nitroso Compounds

The synthesis of sterically hindered anilines has been a significant challenge in organic chemistry. Here we report a Cu-catalyzed radical addition with in situ-generated nitroso compounds to prepare sterically hindered amines directly from readily available materials. The transformation is conducted at room temperature, uses abundant copper salts, and is tolerant of a range of functional groups.
Distributed hierarchical control architecture for transient dynamics improvement in power systems

In this paper, a novel distributed hierarchical control architecture is proposed for large-scale power systems. The newly proposed architecture facilitates faster and more accurate frequency restoration during primary frequency control, by providing decentralized robust control to several selected pilot generators in each area. At the local level, these decentralized robust controllers are designed to quickly damp scillations and restore frequency after large faults and disturbances in the system. Incorporating this supplementary governor control helps the system reach the nominal frequency without necessarily requiring secondary frequency control. Thus, at the area level, automatic generation control (AGC) actions are alleviated in terms of conducting frequency restoration. Moreover, at the area level, AGC coordinates with the decentralized robust controllers to successfully perform tie-line power balancing, while efficiently damping low-frequency inter-area oscillations. The interaction of local and area controllers is validated through detailed simulations.
Overseas assembly and country sourcing choices

Abstract This paper studies the cross-country pattern of U.S. overseas assembly activities between 1980 and 2000 to examine how outsourcing decisions are affected by changes in country and competitor costs. A number of interesting regularities emerge. When a country's costs rise, the share of U.S. overseas assembly activities in that location decline. Conversely, a country's share grows when competitor country costs increase. While own and competitor country costs affect overseas assembly in all countries, the magnitude of these effects is larger for developing countries. In many cases, the measured cost responses appear to correspond with outsourcing theories that are based on search and customization costs.
A high-reliability, low-cost, interleaved bridge converter

The interleaved bridge topology uses two transformers in series to act as both inductor and transformer, allowing zero-voltage resonant transition switching for high-frequency, low-loss operation. High frequency reduces the requirement for large filter capacitors and reduces the size of the magnetics. Costs are reduced by trading electrolytic capacitors for ceramic capacitors, which also improves reliability. Costs are also reduced by eliminating gate driving isolation transformers and snubbers. Experimental results compare favorably with previous designs and costs. Both cost and reliability concerns are discussed. >
NUMERICAL STUDY OF ACTIVE FLOW CONTROL FOR A TRANSITIONAL HIGHLY-LOADED LOW-PRESSURE TURBINE

Active control was simulated numerically for the subsonic flow through a highly loaded low-pressure turbine. The configuration approximated cascade experiments that were conducted to investigate a reduction in turbine stage blade count, which can decrease both weight and mechanical complexity. At a nominal Reynolds number of 25,000 based upon axial chord and inlet conditions, massive separation occurred on the suction surface of each blade due to uncovered turning. Vortex generating jets were then used to help mitigate separation, thereby reducing wake losses. Computations were performed using both steady blowing and pulsed mass injection to study the effects of active flow control on the transitional flow occurring in the aft-blade and near-wake regions. The numerical method utilized a centered compact finite-difference scheme to represent spatial derivatives, that was used in conjunction with a low-pass Pade-type nondispersive filter operator to maintain stability. An implicit approximately factored time-marching algorithm was employed, and Newton-like subiterations were applied to achieve second-order temporal accuracy. Calculations were carried out on a massively parallel computing platform, using domain decomposition to distribute subzones on individual processors. A high-order overset grid approach preserved spatial accuracy in locally refined embedded regions. Features of the flowfields are described, and simulations are compared with each other, with available experimental data, and with a previously obtained baseline case for the noncontrolled flow
IDENTIFYING LENSES WITH SMALL-SCALE STRUCTURE. I. CUSP LENSES

When the source in a four-image gravitational lens system lies sufficiently close to a fold caustic, two of the lensed images lie very close together. If the lens potential is smooth on the scale of the separation between the two close images, the difference between their fluxes should approximately vanish, Rfold ≡ (F+ - F-)/(F+ + F-) ≈ 0. (The subscript indicates the image parity.) Violations of this fold relation in observed lenses are thought to indicate the presence of structure on scales smaller than the separation between the close images. We present a detailed study of the fold relation in realistic smooth lenses, finding it to be more subtle and rich than was previously realized. The degree to which Rfold can differ from zero for smooth lenses depends not only on the distance of the source from the caustic, but also on its location along the caustic, and then on the angular structure of the lens potential (ellipticity, multipole modes, and external shear). Since the source position is unobservable, it is impossible to say from Rfold alone whether the flux ratios in an observed lens are anomalous or not. Instead, we must consider the full distribution of Rfold values that can be obtained from smooth lens potentials that reproduce the separation d1 between the two close images and the distance d2 to the next nearest image. (By reducing the image configuration to these two numbers, we limit our model dependence and obtain a generic analysis.) We show that the generic features of this distribution can be understood, which means that the fold relation provides a robust probe of small-scale structure in lens galaxies. We then compute the full distribution using Monte Carlo simulations of realistic smooth lenses. Comparing these predictions with the data, we find that five of the 12 known lenses with fold configurations have flux ratio anomalies: B0712+472, SDSS 0924+0219, PG 1115+080, B1555+375, and B1933+503. Combining this with our previous analysis revealing anomalies in three of the four known lenses with cusp configurations, we conclude that at least half (8/16) of all four-image lenses that admit generic, local analyses exhibit flux ratio anomalies. The fold and cusp relations do not reveal the nature of the implied small-scale structure, but do provide the formal foundation for substructure studies, and also indicate which lenses deserve further study. Although our focus is on close pairs of images, we show that the fold relation can be used—with great care—to analyze all image pairs in all 22 known four-image lenses and reveal lenses with some sort of interesting structure.
Representation of average drop sizes in sprays

Procedures are presented for processing drop-size measurements to obtain average drop sizes that represent overall spray characteristics. These procedures are not currently in general use, but they would represent an improvement over current practice. Clear distinctions are made between processing data for spatial- and temporal-type measurements (also referred to as concentration-sensitive and flux-sensitive, respectively). The conversion between spatial and temporal measurements is discussed. The application of these procedures is demonstrated by processing measurements of the same spray by two different types of instruments, a laser-diffraction drop sizer and a phase-Doppler particle analyzer.
Microwave-assisted Henry reaction: Solventless synthesis of conjugated nitroalkenes

Abstract In a solventless system and under microwave irradiation, nitroalkanes react with arylaldehydes in the presence of a catalytic amount of ammonium acetate to afford, in one step, conjugated nitroalkenes without the isolation of intermediary β-nitro alcohols.
Arginase: Structure, Mechanism, and Physiological Role in Male and Female Sexual Arousal

Mammalian arginases I and II require an intact binuclear manganese cluster for the hydrolysis of L-arginine to generate L-ornithine and urea. Although arginase isozymes differ in terms of their tissue distribution, cellular localization, and metabolic function, each employs a metal-activated hydroxide mechanism for catalysis. To date, the best arginase inhibitors are those bearing N-hydroxyguanidinium or boronic acid "warheads" that can bridge the binuclear manganese cluster. Strikingly, the trigonal planar boronic acids undergo nucleophilic attack by hydroxide ion to form tetrahedral boronate anions that mimic the tetrahedral intermediate and its flanking transition states in the arginase mechanism. Given their affinity and specificity for arginase, boronic acid inhibitors are especially useful for probing the role of arginase in living systems. Arginase can regulate L-arginine bioavailability to nitric oxide synthase by depleting the substrate pool for NO biosynthesis, so arginase inhibition can enhance the substrate pool for NO biosynthesis. Accordingly, arginase inhibition can enhance NO-dependent physiological processes, such as the smooth muscle relaxation required for sexual arousal: administration of arginase inhibitors in vitro and in vivo enhances erectile function and engorgement in the male and female genitalia. Therefore, arginase is a potential therapeutic target for the treatment of sexual arousal disorders in men and women.
How Many Struggle To Get By In Retirement

Purpose : This study compared the offi cial poverty rate for adults aged 65 years and older with alternative measures that portray the true resources and needs of older adults. Design and Methods : The analysis used data from the 2004 Health and Retirement Study on income, assets, in-kind transfers, and out-of-pocket medical expenses. It also incorporated the effects of federal and state income taxes on net incomes, and accounted for the potential annuity value of assets in measuring resources. Results : The alternative poverty measures that account for outof-pocket health spending estimate that between 0.3 and 1.5 million more older adults live in poverty than acknowledged by the offi cial measure. Implications : These results highlight the need to update poverty measures so that they better refl ect older adults ’ circumstances. This will become increasingly important as policymakers consider reforms to improve solvency in the Social Security and Medicare programs that may require benefi t cuts or increased cost sharing.
Optimal Advertising and Pricing in a Dynamic Durable Goods Supply Chain

Cooperative advertising is an incentive offered by a manufacturer to influence retailers’ promotional decisions. We study a dynamic durable goods duopoly with a manufacturer and two independent and competing retailers. The manufacturer, as a Stackelberg leader, announces his wholesale prices and his shares of retailers’ advertising costs, and the retailers in response play a Nash differential game in choosing their optimal retail prices and advertising efforts over time. We obtain the feedback equilibrium policies for the manufacturer and the retailers in explicit form for a linear demand formulation. We investigate issues, like channel coordination and antidiscriminatory legislation, and also study a case, when the manufacturer sells through only one retailer and the second retailer sells a competing brand.
Which Countries Have State Religions

Among 188 countries, 72 had no state religion in 2000,1970, and 1900; 58 had a state religion throughout; and 58 had 1 or 2 transitions. We use a Hotelling spatial competition model to analyze the likelihood that the religion market would be monopolized. Similar forces influence a government's decision to establish a state religion. Consistent with the model, the probability of state religion in 1970 and 2000 is increasing with the adherence rate to the main religion, has a nonlinear relation with population, and has little relation with per capita GDP. The probability of state religion decreases sharply under Communism, but lagged Communism has only a weak effect. With costly adjustment for institutions, the probability of state religion in 1970 or 2000 depends substantially on the status in 1900. This persistence is much stronger for countries with no major regime change than for countries with such a change.
Computers and the Wage Structure

A leading explanation for the growth of wage inequality is that greater use of information technology increased the demand for human capital. This paper identifies four different explanations for the relationships between computers, skills, and wages: computer-specific human capital, greater general human capital among computer users, greater general human capital for both users and nonusers due to contextual effects, and skill-biased changes in the job composition of the workforce. The paper tests the first three explanations and finds little support for them once pre-computer and other job characteristics are adequately controlled. This conclusion receives further support from a comparison of the timing of inequality growth and computer diffusion and from analyses of the contribution of computer use to overall inequality growth using DiNardo, Fortin, and Lemieux's (1996) reweighting standardization technique.
Distributed Non-Stochastic Experts

We consider the online distributed non-stochastic experts problem, where the distributed system consists of one coordinator node that is connected to k sites, and the sites are required to communicate with each other via the coordinator. At each time-step t, one of the k site nodes has to pick an expert from the set {1, ..., n}, and the same site receives information about payoffs of all experts for that round. The goal of the distributed system is to minimize regret at time horizon T, while simultaneously keeping communication to a minimum. The two extreme solutions to this problem are: (i) Full communication: This essentially simulates the non-distributed setting to obtain the optimal O(√log(n)T) regret bound at the cost of T communication. (ii) No communication: Each site runs an independent copy – the regret is O(√log(n)kT) and the communication is 0. This paper shows the difficulty of simultaneously achieving regret asymptotically better than √kT and communication better than T. We give a novel algorithm that for an oblivious adversary achieves a non-trivial trade-off: regret O(√k5(1+e)/6T) and communication O(T/ke), for any value of e ∈ (0, 1/5). We also consider a variant of the model, where the coordinator picks the expert. In this model, we show that the label-efficient forecaster of Cesa-Bianchi et al. (2005) already gives us strategy that is near optimal in regret vs communication trade-off.
Real and Virtual Competition

Goods sold by electronic firms are not perfect substitutes for otherwise identical goods sold by their offline counterparts. Online purchases are associated with waiting costs, and they do not allow consumers to inspect the product prior to purchase. Visiting a conventional retailer, on the other hand, involves positive travelling costs. In this paper I extend the circular city model to include two types of firms, conventional and electronic. I show that under some parameter configurations, conventional stores actually raise their prices in response to entry of electronic firms. Moreover, economic welfare goes down.
Punishing the Awkward, the Stupid, the Weak, and the Selfish: The Culpability of Negligence

Negligence is a problematic basis for being morally blamed and punished for having caused some harm, because in such cases there is no choice to cause or allow—or risk causing or allowing—such harm to occur. The standard theories as to why inadvertent risk creation can be blameworthy despite the lack of culpable choice are that in such cases there is blame for: (1) an unexercised capacity to have adverted to the risk; (2) a defect in character explaining why one did not advert to the risk; (3) culpably acquiring or failing to rid oneself of these defects of character at some earlier time; (4) flawed use of those practical reasoning capacities that make one the person one is; or (5) chosen violation of per se rules about known precautions. Although each of these five theories can justify blame in some cases of negligence, none can justify blame in all cases intuitively thought to be cases of negligence, nor can any of these five theories show why inadvertent creation of an unreasonable risk, pure and simple, can be blameworthy.
Computation of multiphase systems with phase field models

Phase field models offer a systematic physical approach for investigating complex multiphase systems behaviors such as near-critical interfacial phenomena, phase separation under shear, and microstructure evolution during solidification. However, because interfaces are replaced by thin transition regions (diffuse interfaces), phase field simulations require resolution of very thin layers to capture the physics of the problems studied. This demands robust numerical methods that can efficiently achieve high resolution and accuracy, especially in three dimensions. We present here an accurate and efficient numerical method to solve the coupled Cahn-Hilliard/Navier-Stokes system, known as Model H, that constitutes a phase field model for density-matched binary fluids with variable mobility and viscosity. The numerical method is a time-split scheme that combines a novel semi-implicit discretization for the convective Cahn-Hilliard equation with an innovative application of high-resolution schemes employed for direct numerical simulations of turbulence. This new semi-implicit discretization is simple but effective since it removes the stability constraint due to the nonlinearity of the Cahn-Hilliard equation at the same cost as that of an explicit scheme. It is derived from a discretization used for diffusive problems that we further enhance to efficiently solve flow problems with variable mobility and viscosity. Moreover, we solve the Navier-Stokes equations with a robust time-discretization of the projection method that guarantees better stability properties than those for Crank-Nicolson-based projection methods. For channel geometries, the method uses a spectral discretization in the streamwise and spanwise directions and a combination of spectral and high order compact finite difference discretizations in the wall normal direction. The capabilities of the method are demonstrated with several examples including phase separation with, and without, shear in two and three dimensions. The method effectively resolves interfacial layers of as few as three mesh points. The numerical examples show agreement with analytical solutions and scaling laws, where available, and the 3D simulations, in the presence of shear, reveal rich and complex structures, including strings.
NEAR-INFRARED COUNTERPARTS TO CHANDRA X-RAY SOURCES TOWARD THE GALACTIC CENTER. II. DISCOVERY OF WOLF-RAYET STARS AND O SUPERGIANTS

We present new identifications of infrared counterparts to the population of hard X-ray sources near the Galactic center detected by the Chandra X-ray Observatory. We have spectroscopically confirmed 16 new massive stellar counterparts to the X-ray population, including nitrogen-type (WN) and carbon-type (WC) Wolf-Rayet stars, and O supergiants. These discoveries increase the total sample of massive stellar X-ray sources in the Galactic center region to 30 (possibly 31). For the majority of these sources, the X-ray photometry is consistent with thermal emission from plasma having temperatures in the range of kT = 1-8 keV or non-thermal emission having power-law indices in the range of –1 ≲ Γ ≲ 3, and X-ray luminosities in the range of L_X ~ 10^(32)-10^(34) erg s^(–1) (0.5-8.0 keV). Several sources have exhibited X-ray variability of several factors between observations. These X-ray properties are not a ubiquitous feature of single massive stars but are typical of massive binaries, in which the high-energy emission is generated by the collision of supersonic winds, or by accretion onto a compact companion. However, without direct evidence for companions, the possibility of intrinsic hard X-ray generation from single stars cannot be completely ruled out. The spectral energy distributions of these sources exhibit significant infrared excess, attributable to free-free emission from ionized stellar winds, supplemented by hot dust emission in the case of the WC stars. With the exception of one object located near the outer regions of the Quintuplet cluster, most of the new stars appear isolated or in loose associations. Seven hydrogen-rich WN and O stars are concentrated near the Sagittarius B H II region, while other similar stars and more highly evolved hydrogen-poor WN and WC stars lie scattered within ≈50 pc, in projection, of Sagitarrius A West. We discuss various mechanisms capable of generating the observed X-rays and the implications these stars have for massive star formation in the Galaxy's Central Molecular Zone.
Interpreting the volatility smile : an examination of the information content of option prices

This paper evaluates how useful the information contained in options prices is for predicting future price movements of the underlying assets. We develop an improved semiparametric methodology for estimating risk-neutral probability density functions (PDFs), which allows for skewness and intertemporal variation in higher moments. We use this technique to estimate a daily time series of risk-neutral PDFs spanning the late 1980's through 1999, for S&P 500 futures, U.S. dollar/Japanese yen futures and U.S. dollar/deutsche mark futures, using options on these futures. For the foreign exchange futures, we find little discernable additional information contained in the estimated PDFs beyond the information derived from the Black-Scholes model, a fully parametric specification. For S&P 500 futures, we find that the risk-neutral distribution implied by the volatility smile better fits the realized returns than the Black-Scholes model, although this better overall fit is not exhibited in the second and third moments.
Chemical Equilibrium Abundances in Brown Dwarf and Extrasolar Giant Planet Atmospheres

We explore detailed chemical equilibrium abundance profiles for a variety of brown dwarf and extrasolar giant planet atmosphere models, focusing in particular on Gl 229B, and derive the systematics of the changes in the dominant reservoirs of the major elements with altitude and temperature. We assume an Anders & Grevesse solar composition of 27 chemical elements and track 330 gas-phase species, including the monatomic forms of the elements, as well as about 120 condensates. In our fiducial, limiting reference model, we do not assume that condensation sequesters elements at depth and present true chemical equilibrium calculations for the solar element mix. However, there is evidence in the atmosphere of Gliese 229B that it is depleted in heavy elements. To explore depletion and rainout, which are fundamentally nonequilibrium processes, we perform a series of rainout calculations in which refractory elements are withdrawn from the equilibrium in stoichiometric ratios via an ad hoc algorithm. Then we compare the true equilibrium results with the rainout results, with an eye to understanding the near-infrared spectrum of Gliese 229B, as well as the new "L dwarfs" with Teff's above ~1500 K. We address the issue of the formation and composition of clouds in the cool atmospheres of substellar objects. We conclude that the opacity of clouds of low-temperature (≤900 K), small-radius condensables (specific chlorides and sulfides, not silicates), may in part be responsible for the steep spectrum of Gl 229B observed in the near-IR below 1 μm. We assemble a temperature sequence of chemical transitions in substellar atmospheres that may be used to anchor and define a sequence of spectral types for substellar objects with Teff's from ~2200 to ~100 K.
A mapping approach for designing neural sub-nets

Summary form only given. Several investigators have constructed backpropagation (BP) neural networks by assembling smaller, pretrained building blocks. This approach leads to faster training and provides a known topology for the network. The authors have carried this process down one additional level by describing methods for mapping given functions to subblocks. First, polynomial, approximations to the desired function were found. Then the polynomial was mapped to a BP network, using an extension of a constructive proof to universal approximation. >
Incubator firm failure or graduation? The role of university linkages

One of the theoretically important factors for incubator firm performance is the strength of their linkages to the research university sponsoring the technology incubator. Herein, we focus on two types of university linkages to the sponsoring institution: a license obtained from the university and a link to university faculty, while controlling for incubator firm linkages to nonsponsoring research universities, among other factors. We propose that a university link to the sponsoring institution reduces the probability of new venture failure and, at the same time, retards timely graduation. Further, we suggest that these effects are more pronounced the stronger the university link. Due to the difficulty of obtaining fine-grained longitudinal data, the incubation literature is characterized by a dearth of studies focusing on incubator firm differential performance. We attempt to take a first step towards closing this gap by testing these hypotheses through following 79 start-up firms incubated in the Advanced Technology Development Center at the Georgia Institute of Technology over the 6-year period between 1998 and 2003. We find broad support for the hypotheses advanced. © 2005 Elsevier B.V. All rights reserved.
Synthesis of Cyclopropanes via Organoiron Methodology: Preparation and Rearrangement of Divinylcyclopropanes

Addition of alkenyl Grignard reagents to (1-methoxycarbonylpentadienyl)iron(1+) cation generates the corresponding (2-alkenylpent-3-en-1,5-diyl)iron complexes. Oxidatively induced-reductive elimination of these complexes gives divinylcyclopropanes which can undergo subsequent Cope rearrangement to give 1,4-cycloheptadienes.
Unified 3D models for multisensor image synthesis

Abstract A method for modeling three-dimensional objects for multi-sensory images and feature prediction is presented. The object representation is a modified volume-surface octree created using volume intersection based on the object's silhouettes. This representation is easy to construct and is shown to be well adapted for the simulations of the physical processes that affect the generation of the different imagery. A novel technique is developed that eliminates false volumes in the model created during the process of backprojecting the silhouettes in the volume intersection algorithm. This technique is shown to be valid for the important class of objects defined by simple engineering drawings. The elimination of false volumes increases the accuracy of the volumetric fit of the simulated object to the modeled object. The improved model supports the generation of realistic imagery in three imaging modes: video, thermal, and laser radar. Thermal image simulation based on the modeling of complex objects with nonhomogeneities and time-varying heat generation is described. A computationally efficient, implicit finite difference method is described for the simulation of energy flow within objects and between the object surface and the environment, The prediction of laser radar (ladar) images uses a statistical model to predict speckle noise, which allows the synthesis of realistic imagery. Examples of the multisensory imagery produced by this scheme are presented. The imagery and features values predicted by this unified modeling scheme may be used to train multisensorbased object recognition systems.
Distance Distributions in Finite Uniformly Random Networks: Theory and Applications

In wireless networks, knowledge of internode distances is essential for performance analysis and protocol design. When determining distance distributions in random networks, the underlying nodal arrangement is almost universally taken to be a stationary Poisson point process. While this may be a good approximation in some cases, there are also certain shortcomings to this model, such as the fact that, in practical networks, the number of nodes in disjoint areas is not independent. This paper considers a more-realistic network model where a known and fixed number of nodes are independently distributed in a given region and characterizes the distribution of the Euclidean internode distances. The key finding is that, when the nodes are uniformly randomly placed inside a ball of arbitrary dimensions, the probability density function (pdf) of the internode distances follows a generalized beta distribution. This result is applied to study wireless network characteristics such as energy consumption, interference, outage, and connectivity.