cssi/SciSciGPT-SciSciNet huggingface dataset:
Eliciting single-peaked preferences using comparison queries

Voting is a general method for aggregating the preferences of multiple agents. Each agent ranks all the possible alternatives, and based on this, an aggregate ranking of the alternatives (or at least a winning alternative) is produced. However, when there are many alternatives, it is impractical to simply ask agents to report their complete preferences. Rather, the agents' preferences, or at least the relevant parts thereof, need to be elicited. This is done by asking the agents a (hopefully small) number of simple queries about their preferences, such as comparison queries, which ask an agent to compare two of the alternatives. Prior work on preference elicitation in voting has focused on the case of unrestricted preferences. It has been shown that in this setting, it is sometimes necessary to ask each agent (almost) as many queries as would be required to determine an arbitrary ranking of the alternatives. In contrast, in this paper, we focus on single-peaked preferences. We show that such preferences can be elicited using only a linear number of comparison queries, if either the order with respect to which preferences are single-peaked is known, or at least one other agent's complete preferences are known. We show that using a sublinear number of queries does not suffice. We also consider the case of cardinally single-peaked preferences. For this case, we show that if the alternatives' cardinal positions are known, then an agent's preferences can be elicited using only a logarithmic number of queries; however, we also show that if the cardinal positions are not known, then a sublinear number of queries does not suffice. We present experimental results for all elicitation algorithms. We also consider the problem of only eliciting enough information to determine the aggregate ranking, and show that even for this more modest objective, a sublinear number of queries per agent does not suffice for known ordinal or unknown cardinal positions. Finally, we discuss whether and how these techniques can be applied when preferences are almost single-peaked.
Asymptotics of almost holomorphic sections of ample line bundles on symplectic manifolds: An addendum

We define a Gaussian measure on the space H 0 J (M, L N ) of almost holomorphic sections of powers of an ample line bundle L over a symplectic manifold (M, ω), and calculate the joint probability densities of sections taking prescribed values and covariant derivatives at a finite number of points. We prove that they have a universal scaling limit as N → ∞. This result will be used in another paper to extend our previous work on universality of scaling limits of correlations between zeros to the almost-holomorphic setting.
GaAs shallow-homojunction solar cells

With the objective of demonstrating the feasibility of fabricating 2 x 2 cm efficient, shallow homojunction GaAs solar cells for space applications, this program addresses the basic problems of material preparation and device fabrication. Significant progress was made and conversion efficiencies close to 16 percent at AM0 were obtained on 2 x 2 cm cells. Measurements and computer analyses on the n(+)/p/p(+) shallow homojunction cells indicate that such cell configuration should be very resistant to 1 MeV electron irradiation.
The parametric sensitivity of CAM5's MJO

We systematically explore the ability of the Community Atmospheric Model version 5 (CAM5) to simulate the Madden-Julian Oscillation (MJO), through an analysis of MJO metrics calculated from a 1100-member perturbed parameter ensemble of 5 year simulations with observed sea surface temperatures. Parameters from the deep convection scheme make the greatest contribution to the variance in MJO simulation quality with a much smaller contribution from parameters in the large-scale cloud, shallow convection, and boundary layer turbulence schemes. Improved MJO variability results from a larger lateral entrainment rate and a reduction in the precipitation efficiency of deep convection that was achieved by a smaller autoconversion of cloud to rainwater and a larger evaporation of convective precipitation. Unfortunately, simulations with an improved MJO also have a significant negative impact on the climatological values of low-level cloud and absorbed shortwave radiation, suggesting that structural in addition to parametric modifications to CAM5's parameterization suite are needed in order to simultaneously well simulate the MJO and mean-state climate.
Study of a kindred with thyroxine-binding globulin deficiency and oligomenorrhea

Abstract The finding of a low total thyroxine level in an oligomenorrheic woman uncovered a new family with thyroxine-binding globulin deficiency and oligomenorrhea. Thirteen of 17 family members had the deficiency of thyroxine-binding globulin, with heterozygous female subjects showing overlap of levels with normal subjects. Oligomenorrhea was frequently found but segregated separately from the thyroxine-binding globulin deficiency; of seven women with low levles, three had normal monthly menstrual cycles. Fertility was not impaired.
Model Selection for High-Dimensional Quadratic Regression via Regularization

ABSTRACTQuadratic regression (QR) models naturally extend linear models by considering interaction effects between the covariates. To conduct model selection in QR, it is important to maintain the hierarchical model structure between main effects and interaction effects. Existing regularization methods generally achieve this goal by solving complex optimization problems, which usually demands high computational cost and hence are not feasible for high-dimensional data. This article focuses on scalable regularization methods for model selection in high-dimensional QR. We first consider two-stage regularization methods and establish theoretical properties of the two-stage LASSO. Then, a new regularization method, called regularization algorithm under marginality principle (RAMP), is proposed to compute a hierarchy-preserving regularization solution path efficiently. Both methods are further extended to solve generalized QR models. Numerical results are also shown to demonstrate performance of the methods. S...
Percentage Contributions from Atmospheric and Surface Features to Computed Brightness Temperatures

Over the past few years, a few solid precipitation detection and retrieval algorithms have been developed and shown to be applicable for snowing clouds and blizzards. Current precipitating snow retrieval algorithms require the use of millimeter-wave radiometer observations. The millimeter-wave frequencies are especially sensitive to the scattering and emission properties of frozen particles due to the ice particle refractive index. These channels can also be used to discern information about the frozen particles above the melting layer. Passive radiometric channels respond to both the integrated particle mass throughout the volume and field of view, and to the amount, location, and size distribution of the frozen (and liquid) particles with the sensitivity varying for different frequencies and hydrometeor types. This work will show the percentage of the brightness temperature resulting from the liquid hydrometeor, frozen hydrometeor, relative humidity, and surface contributions. The focus will be on precipitating snow events and millimeter-wave frequencies however, other events and frequencies will be included in the analysis.
The environmental dependence of neutral hydrogen content in spiral galaxies

We present a study of the relationship between the deficiency of neutral hydrogen and the local three‐dimensional number density of spiral galaxies in the Arecibo catalog [1] of global HI measurements. We find that the dependence on density of the HI content is weak at low densities, but increases sharply at high densities where interactions between galaxies and the intra‐cluster medium become important. This behavior is reminiscent of the morphology‐density relation [2] in that the effect manifests itself only at cluster‐type densities, and indeed when we plot both the HI deficiency‐density and morphology‐density relations, we see that the densities at which they “turn up” are similar. This suggests that the physical mechanisms responsible for the increase in early types in clusters are also responsible for the decrease in HI content.
Precision Muon Physics

Abstract The muon is playing a unique role in sub-atomic physics. Studies of muon decay both determine the overall strength and establish the chiral structure of weak interactions, as well as setting extraordinary limits on charged-lepton-flavor-violating processes. Measurements of the muon’s anomalous magnetic moment offer singular sensitivity to the completeness of the standard model and the predictions of many speculative theories. Spectroscopy of muonium and muonic atoms gives unmatched determinations of fundamental quantities including the magnetic moment ratio μ μ / μ p , lepton mass ratio m μ / m e , and proton charge radius r p . Also, muon capture experiments are exploring elusive features of weak interactions involving nucleons and nuclei. We will review the experimental landscape of contemporary high-precision and high-sensitivity experiments with muons. One focus is the novel methods and ingenious techniques that achieve such precision and sensitivity in recent, present, and planned experiments. Another focus is the uncommonly broad and topical range of questions in atomic, nuclear and particle physics that such experiments explore.
Deterministic Domain Wall Motion Orthogonal To Current Flow Due To Spin Orbit Torque.

Spin-polarized electrons can move a ferromagnetic domain wall through the transfer of spin angular momentum when current flows in a magnetic nanowire. Such current induced control of a domain wall is of significant interest due to its potential application for low power ultra high-density data storage. In previous reports, it has been observed that the motion of the domain wall always happens parallel to the current flow – either in the same or opposite direction depending on the specific nature of the interaction. In contrast, here we demonstrate deterministic control of a ferromagnetic domain wall orthogonal to current flow by exploiting the spin orbit torque in a perpendicularly polarized Ta/CoFeB/MgO heterostructure in presence of an in-plane magnetic field. Reversing the polarity of either the current flow or the in-plane field is found to reverse the direction of the domain wall motion. Notably, such orthogonal motion with respect to current flow is not possible from traditional spin transfer torque driven domain wall propagation even in presence of an external magnetic field. Therefore the domain wall motion happens purely due to spin orbit torque. These results represent a completely new degree of freedom in current induced control of a ferromagnetic domain wall.
Flowering phenology change and climate warming in southwestern Ohio

Global surface temperature has increased markedly over the last 100 years. This increase has a variety of implications for human societies, and for ecological systems. One of the most obvious ways ecosystems are affected by global climate change is through alteration of organisms’ developmental timing (phenology). We used annual botanical surveys that documented the first flowering for an array of species from 1976 to 2003 to examine the potential implications of climate change for plant development. The overall trend for these species was a progressively earlier flowering time. The two earliest flowering taxa (Galanthus and Crocus) also exhibited the strongest shift in first flowering. We detected a significant trend in climate suggesting higher temperatures in winter and spring over the sampling interval and found a significant relationship between warming temperatures and first flowering time for some species. Although 60% of the species in our study flowered earlier over the sampling interval, the remaining species exhibited no statistically detectable change. This variation in response is ostensibly associated with among-species variation in the role of climate cues in plant development. Future work is needed to isolate specific climate cues, and to link plant phenology to the physiological processes that trigger plant development.
Sentiments and rationalizability

Sentiments are characteristics of players' beliefs. I propose two notions of sentiments, confidence and optimism, and I study their role in shaping the set of rationalizable strategy profiles in (incomplete information) games with complementarities. Confidence is related to a player's perceived precision of information; optimism is the sentiment that the outcome of the game will be ``favorable.'' I prove two main results on how sentiments and payoffs interact to determine the size and location of the set of rationalizable profiles. The first result provides an explicit upper bound on the size of the set of rationalizable strategy profiles, relating complementarities and confidence; the second gives an explicit lower bound on the change of location, relating complementarities and optimism. I apply these results to four areas. In models of currency crisis, the results suggest that the most confident investors may drive financial markets. In models of empirical industrial organization, the paper provides a classification of the parameter values for which the model is identified. In non-Bayesian updating, the results clarify the strategic implications of certain biases. Finally, the results generalize and clarify the uniqueness result of global games.
From Mobius To Gyrogroups

Abraham A. UngarAmer. Math. Monthly, Vol. 115(2), (2008), pp. 138–144.1. IntroductionThe evolution from Mo¨bius to gyrogroups began in 1988 [12], and is still ongoingin [14, 15]. Gyrogroups, a natural generalization of groups, lay a fruitful bridgebetween nonassociativealgebraand hyperbolicgeometry, just asgroupslayafruitfulbridge between associative algebra and Euclidean geometry. More than 150 yearshave passed since the German mathematician August Ferdinand Mo¨bius (1790–1868) ﬁrst studied the transformations that now bear his name [9, p. 71]. Yet, therich structure he thereby exposed is still far from being exhausted, as the evolutionfrom Mo¨bius to gyrogroups demonstrates.2. FromM¨obiusMo¨bius transformations of the complex open unit disc D= {z ∈ C: |z| < 1} ofthe complex plane Care studied in most books on function theory of one complexvariable. According to [10, p. 176], these are important for at least two reasons:(i) they play a central role in non-Euclidean geometry [15], and (ii) they are theonly automorphisms of the disc. Ahlfors’ book [1],
The rise and fall of training and visit extension : an Asian mini-drama with an African epilogue

The paper reviews the origins and evolution of the Training and Visit (T&V) extension system, which was promoted by the World Bank in 1975-98 in over 50 developing countries. The discussion seeks to clarify the context within which the approach was implemented, and to analyze the causes for its lack of sustainability and its ultimate abandonment. The paper identifies some of the challenges faced by the T&V approach as being typical of a large public extension system, where issues of scale, interaction with the agricultural research systems, inability to attribute benefits, weak accountability, and lack of political support tend to lead to incentive problems among staff and managers of extension, and limited budgetary resources. The different incentives and outlook of domestic stakeholders and external donor agencies are also reviewed. The main cause of the T&V system's disappearance is attributed to the incompatibility of its high recurrent costs with the limited budgets available domestically, leading to fiscal unsustainability. The paper concludes with some lessons that apply to donor-driven public extension initiatives, and more generally to rural development fads. The role of timely, independent, and rigorous evaluative studies is specifically highlighted.
On a conjecture on Wiener indices in combinatorial chemistry

Drugs and other chemical compounds are often modeled as polygonal shapes called the molecular graph, which can be a path, a tree, or in general any graph. An indicator defined over this molecular graph, the Wiener index, has been shown to be strongly correlated to various chemical properties of the compound. The Wiener index conjecture for trees states that for any integer n (except for a finite set), one can find a tree with Wiener index n. In this paper, we present progress towards proving this conjecture by presenting a 4-parameter family of trees that we show experimentally to affirm the Wiener index conjecture for very large values of n. Given an integer n, we also present efficient algorithms for finding the tree whose Wiener index is n.
Thin-film 'Thermal Well' Emitters and Absorbers for High-Efficiency Thermophotovoltaics

A new approach is introduced to significantly improve the performance of thermophotovoltaic (TPV) systems using low-dimensional thermal emitters and photovoltaic (PV) cells. By reducing the thickness of both the emitter and the PV cell, strong spectral selectivity in thermal emission and absorption can be achieved by confining photons in trapped waveguide modes inside the thin-films that act as thermal analogs to quantum wells. Simultaneously, photo-excited carriers travel shorter distances across the thin-films reducing bulk recombination losses resulting in a lower saturation current in the PV cell. We predict a TPV efficiency enhancement with near-field coupling between the thermal emitter and the PV cell up to 38.7% using a thin-film germanium (Ge) emitter at 1000 K and an ultra-thin gallium antimonide (GaSb) cell supported by perfect back reflectors separated by 100 nm. Even in the far-field limit, the efficiency is predicted to reach 31.5%, which is over an order of magnitude higher than the Shockley Queisser limit of 1.6% for a bulk GaSb cell and a blackbody emitter at 1000 K. The proposed design approach does not require nanoscale patterning of the emitter and PV cell surfaces, but instead offers a simple low-cost solution to improve the performance of thermophotovoltaic systems.
Beyond the Hype of Frictionless Markets: Evidence of Heterogeneity in Price Rigidity on the Internet

We explore daily patterns of Internet pricing for the two major retailers, Amazon.com and Barnes and Noble (BN), using data on 377 books collected over a 449-day period in 2003-4. We frame this investigation in terms of a key question: How rigid are prices on the Internet? Are there reasons to suggest that prior predictions of more flexible prices on the Internet may not have been founded on the appropriate theoretical knowledge? We find that Internet retailers, in contrast with traditional firms, adjust prices any day of the week throughout the year. Yet firms' price adjustments for books occur much less frequently than daily--every 90 days on average. For most observers of Internet-based selling, this is surprising, because most expect more frequent price adjustments--based on the quality of technological environment that supports price-setting. In fact, our results show that price-change activity appears to vary by book category, from a high of one change, on average, every 61 days for best sellers to a low of one change every 184 days, on average, for steady sellers. In addition, we learned that individual firms exhibited different patterns for their price changes: Amazon changed book prices every 222 days, whereas BN changed its book prices more frequently, every 56 days on average.
Low Power Distributed Embedded Systems: Dynamic Voltage Scaling and Synthesis

In this paper, we survey multi-objective system synthesis algorithms for low power real-time systems-on-a-chip (SOCs), distributed and wireless client-server embedded systems, distributed embedded systems with reconfigurable field-programmable gate arrays (FPGAs), as well as distributed systems of SOCs. Many of these synthesis algorithms target simultaneous optimization of different cost objectives, including system price, area and power consumption. Dynamic voltage scaling has proved to be a powerful technique for reducing power consumption. We also survey several dynamic voltage scaling techniques for distributed embedded systems containing voltage-scalable processors. The dynamic voltage scaling algorithms can be embedded in the inner-loop of a system synthesis framework and provide feedback for system-level design space exploration. Besides voltage-scalable processors, dynamically voltage-scalable links have also been proposed for implementing high performance and low power interconnection networks for distributed systems. We survey relevant techniques in this area as well.
The relationship between AND/OR search and variable elimination

In this paper we compare search and inference in graphical models through the new framework of AND/OR search. Specifically, we compare Variable Elimination (VE) and memory-intensive AND/OR Search (AO) and place algorithms such as graph-based backjumping and no-good and good learning, as well as Recursive Conditioning [7] and Value Elimination [2] within the AND/OR search framework.
Organic Resilience for Tactical Environments

In this paper we present a tactical defense infrastructure for mission survivability based on three core inspirations from biological systems: multi-potentiation, feedback mechanisms, and redundancy. In tactical operational environments, these concepts may be realized through a combination of capabilities that include (1) dynamic allocation of resources for mission execution, (2) detection and identification of attacks and their effects, and (3) information sharing for system adaptation. As a proof-of-concept we introduce an extensible, multi-layer defense infrastructure inspired in the self-organization and resilience properties of biological systems. Two defense strategies are considered to validate the proposed model: a fast response consisting on rebooting a compromised system from a reference system image; and a slower response involving a process of identification of the attack, which then allows the node to change its base configuration and reboot to a state that is potentially immune to the same attack. Our experimental results show that the second strategy improves the overall resilience of the system for ongoing attacks after an initial exposure phase.
Solid oxide fuel cells for power generation

Solid oxide fuel cells (SOFCs), based on an oxide ion conducting electrolyte, offer a clean, low-pollution technology to electrochemically generate electricity at high efficiencies. These fuel cells provide many advantages over traditional energy conversion systems including high efficiency, reliability, modularity, fuel adaptability, and very low levels of SOx and NOx emissions. Quiet, vibration-free operation of SOFCs also eliminates noise usually associated with conventional power generation systems. Furthermore, because of their high operation temperature (600–1000°C), some hydrocarbon fuels such as natural gas can be reformed within the cell stack eliminating the need for an expensive, external reformer. In spite of these advantages, the degree and extent of their market penetration really depends on the ability to reduce the cost of SOFC-based power systems while ensuring their long-term durability. This article reviews the cell and stack materials, cell designs, and present commercial status of power systems built using SOFCs. Conflict of interest: The author has declared no conflicts of interest for this article.
Tidally driven mixing and dissipation in the stratified boundary layer above steep submarine topography

A tidally driven, stratified boundary layer over supercritical topography is simulated numerically. The near-boundary flow is characterized by quasiperiodic, bore-like motions and episodic expulsion events where fluid is ejected into the stratified interior. The character of the bores is compared to the high-resolution ocean mooring data of van Haren (2006). The diffusivity of the flow near the boundary is estimated by means of a synthetic dye tracer experiment. The average dissipation rate within the dye cloud is computed and combined with the diffusivity estimate to yield an overall mixing efficiency of 0.15. Both the estimated diffusivity and dissipation rates are in reasonable agreement with the microstructure observations of Kunze et al. (2012) when scaled to the environmental conditions at the Monterey and Soquel Canyons and to the values estimated by van Haren and Gostiaux (2012) above the sloping bottom of the Great Meteor Seamount in the Canary Basin.
Density-matrix based determination of low-energy model Hamiltonians from ab initio wavefunctions

We propose a way of obtaining effective low energy Hubbard-like model Hamiltonians from ab initio quantum Monte Carlo calculations for molecular and extended systems. The Hamiltonian parameters are fit to best match the ab initio two-body density matrices and energies of the ground and excited states, and thus we refer to the method as ab initio density matrix based downfolding. For benzene (a finite system), we find good agreement with experimentally available energy gaps without using any experimental inputs. For graphene, a two dimensional solid (extended system) with periodic boundary conditions, we find the effective on-site Hubbard U(∗)/t to be 1.3 ± 0.2, comparable to a recent estimate based on the constrained random phase approximation. For molecules, such parameterizations enable calculation of excited states that are usually not accessible within ground state approaches. For solids, the effective Hamiltonian enables large-scale calculations using techniques designed for lattice models.
Resonant tunneling and intrinsic bistability in twisted graphene structures

We predict that vertical transport in heterostructures formed by twisted graphene layers can exhibit a unique bistability mechanism. Intrinsically bistable $I\text{\ensuremath{-}}V$ characteristics arise from resonant tunneling and interlayer charge coupling, enabling multiple stable states in the sequential tunneling regime. We consider a simple trilayer architecture, with the outer layers acting as the source and drain and the middle layer floating. Under bias, the middle layer can be either resonant or nonresonant with the source and drain layers. The bistability is controlled by geometric device parameters easily tunable in experiments. The nanoscale architecture can enable uniquely fast switching times.
SelfishMigrate: A Scalable Algorithm for Non-clairvoyantly Scheduling Heterogeneous Processors

We consider the classical problem of minimizing the total weighted flow-time for unrelated machines in the online non-clairvoyant setting. In this problem, a set of jobs J arrive over time to be scheduled on a set of M machines. Each job J has processing length pj, weight wj, and is processed at a rate of lij when scheduled on machine i. The online scheduler knows the values of wj and lij upon arrival of the job, but is not aware of the quantity pj. We present the first online algorithm that is scalable ((1+e)-speed O(1/2)-competitive for any constant e > 0) for the total weighted flow-time objective. No non-trivial results were known for this setting, except for the most basic case of identical machines. Our result resolves a major open problem in online scheduling theory. Moreover, we also show that no job needs more than a logarithmic number of migrations. We further extend our result and give a scalable algorithm for the objective of minimizing total weighted flow-time plus energy cost for the case of unrelated machines. In this problem, each machine can be sped up by a factor of f-1i(P) when consuming power P, where fi is an arbitrary strictly convex power function. In particular, we get an O(γ2)-competitive algorithm when all power functions are of form sγ. These are the first non-trivial non-clairvoyant results in any setting with heterogeneous machines. The key algorithmic idea is to let jobs migrate selfishly until they converge to an equilibrium. Towards this end, we define a game where each job's utility which is closely tied to the instantaneous increase in the objective the job is responsible for, and each machine declares a policy that assigns priorities to jobs based on when they migrate to it, and the execution speeds. This has a spirit similar to coordination mechanisms that attempt to achieve near optimum welfare in the presence of selfish agents (jobs). To the best our knowledge, this is the first work that demonstrates the usefulness of ideas from coordination mechanisms and Nash equilibria for designing and analyzing online algorithms.
Quantum Chemical Analysis of the Energetics of the anti- and gauche- Conformers of Ethanol

Ethanol displays two stable conformers, the classic anti (or trans) form and a gauche conformation in which the hydroxyl hydrogen points toward one of the methyl hydrogens. Surprisingly, the two forms have nearly equal energies, and in the vapor phase the gauche form predominates because of its twofold degeneracy. An analysis of the energetics of these conformers based on natural bond orbital analysis helps to explain the apparently anomalous near degeneracy of these conformers.
Photo-Induced Rearrangements of Allyl and Benzyl Phosphites. Potential Phosphoranyl 1,3-Biradical Intermediates

Abstract Allyl and benzyl phosphites undergo photoisomerization to the corresponding allyl- and benzylphosphonates. The triplet-sensitized photorearrangements of the allyl systems are regiospecific. A triplet 5-membered ring 1,3-phosphoranyl biradical intermediate is proposed. Optically active phosphites, chiral at the benzyl carbon, undergo intramolecular photo-Arbuzov rearrangement with very predominant retention of configuration at carbon.
Verifiable Delegated Set Intersection Operations on Outsourced Encrypted Data

We initiate the study of the following problem: Suppose Alice and Bob would like to outsource their encrypted private data sets to the cloud, and they also want to conduct the set intersection operation on their plaintext data sets. The straightforward solution for them is to download their outsourced cipher texts, decrypt the cipher texts locally, and then execute a commodity two-party set intersection protocol. Unfortunately, this solution is not practical. We therefore motivate and introduce the novel notion of Verifiable Delegated Set Intersection on outsourced encrypted data (VDSI). The basic idea is to delegate the set intersection operation to the cloud, while (i) not giving the decryption capability to the cloud, and (ii) being able to hold the misbehaving cloud accountable. We formalize security properties of VDSI and present a construction. In our solution, the computational and communication costs on the users are linear to the size of the intersection set, meaning that the efficiency is optimal up to a constant factor.
Masculinity in Adolescent Males’ Early Romantic and Sexual Heterosexual Relationships

There is a need to understand better the complex interrelationship between the adoption of masculinity during adolescence and the development of early romantic and sexual relationships. The purpose of this study was to describe features of adolescent masculinity and how it is expressed in the contexts of early to middle adolescent males' romantic and sexual relationships. Thirty-three 14- to 16-year-old males were recruited from an adolescent clinic serving a community with high sexually transmitted infection rates and were asked open-ended questions about their relationships-how they developed, progressed, and ended. Participants described a high degree of relationally oriented beliefs and behaviors related to romantic and sexual relationships, such as a desire for intimacy and trust. The males also described a more limited degree of conventionally masculine beliefs and behaviors. These beliefs and behaviors often coexisted or overlapped. Implications for the clinical care of similar groups of adolescents are described.
Bistability in grating-tuned external-cavity semiconductor lasers

Bistability has been observed in the tuning characteristic and power versus current relation of a 1.3 μm grating-tuned external-cavity semiconductor laser. Tuning-direction reversal, current variations, and feedback interruption can change the output power and threshold current at a given wavelength. These effects are shown theoretically to be due to the coupling of the semiconductor gain and index of refraction. From measurements of the semiconductor chip facet reflectivity, solitary laser diode mode spectrum, and tuning curve in the presence of external feedback, the analysis yields values for the external feedback strength, semiconductor modal loss, and linewidth enhancement factor. Using an InGaAsP double-channel-planar-buried-heterostructure laser diode with a 4 percent reflectivity antireflection-coated facet inside an external cavity consisting of a 0.60 numerical aperture lens and a 1200 line/mm diffraction grating, we found 22 percent external feedback, 60 cm-1modal loss, and a linewidth enhancement factor \alpha = -7.1 .
Visual and radiometric photometry of 1580 Betulia

Broadband visual and 10.6-micron photometry of 1580 Betulia was obtained during its close approach to earth in May 1976. The photometry was analyzed by using the 'radiometric method' to derive the radius (2.10 + or - 0.40 km) and albedo (0.108 + or - 0.012) of Betulia. Radar and polarimetric results indicate a radius greater than 3.0 km and a geometric albedo of about 0.05. To be compatible with these results, Betulia was also modeled as having a surface with the thermal characteristics of bare rock rather than those of the 'lunar' regolith model used for previous analysis of radiometry of other asteroids. A 3.7-km radius and a geometric albedo of about 0.04 are compatible with all available observations. Betulia is the first Mars-crossing asteroid found to have such a low albedo, which may be indicative of carbonaceous surface material.
The Turn to Truth: Trends in Truth Commission Experimentation

Interest in cross-national comparison of transitional justice mechanisms has grown recently, as has the study of truth commissions in particular. However, as is true of many emerging areas of research, progress has been hampered by significant gaps in data and by a lack of consensus as to what constitutes the universe of cases. To address this problem, this article introduces the most comprehensive truth commission database we know to be in existence. First, we describe the process of collecting information on truth commission cases and outline our logic in determining what cases to include in the database. Then, we briefly discuss the attributes of truth commission cases included in the database and explain our reasoning regarding their inclusion. Finally, we use the data to provide an overview of patterns and trends in the use of truth commissions.
High-temperature oxide melt calorimetry of oxides and nitrides☆

Abstract Thermochemical data for ceramic materials are essential both for understanding fundamental solid state chemistry (structure, bonding, and crystal chemical systematics, as well as vibrational, magnetic, optical, and electronic phenomena) and for predicting phase equilibria, materials compatibility, and reactivity. This Hugh M. Huffman Memorial Award Lecture describes recent advances in high-temperature oxide melt calorimetry in the University of California Davis Thermochemistry Facility and illustrates its application to three problems of technological significance: the relative stability ofα - and β -silicon nitride; the inversion of stability of α - and γ -alumina at the nanoscale, and the ion exchange of cesium and sodium in silicotitanate zeolite-like materials proposed as hosts for radioactive waste.
Small angle x-ray scattering studies of the size, shape, and hydration of catalase.

Abstract Information concerning the size, shape, and hydration of the catalase molecule in solution has been obtained from small angle X-ray scattering. The scattering curve was determined over an intensity range extending to 6·10−4 of the central intensity. The radius of gyration of the molecule is found to be 39.8 ± 0.4 A. The shape appears to be that of a slightly elongated figure whose length is about twice the average cross-sectional diameter. The electron pair distribution is calculated from the scattering curve and indicates a maximum linear dimension of 146 ± 10 A. The scattering from catalase solutions from which the solvent density is varied is also described. From these experiments, the average electron density of the catalase molecule in solution is found to be 0.425 electrons/A3. The results are interpreted as indicating that there is considerable internal water of hydration which swells the molecule.
Turbulent boundary layer on a cylinder in axial flow

Abstract : This report reviews research on the turbulent boundary layer that develops on a cylinder in axial flow. Experimental results indicate that the transverse curvature results in a higher coefficient of friction and a fuller velocity profile than for a planar boundary layer. However, appropriate scaling laws and nondimensional scaling parameters are still elusive. The few turbulence measurements such as Reynolds stress and intermittency that are available for a cylindrical boundary layer suggest that the distribution of turbulent quantities in the boundary layer is somewhat different from a planar boundary layer, particularly as the boundary layer becomes thick compared to the radius of the cylinder. This is most likely a result of the tendency for a cylindrical boundary layer to become wake-like as the cylinder becomes very small. Measurements of turbulence intensity and detection of turbulence-generating events in a cylindrical boundary layer suggest that the mechanism for the production of turbulence near the wall is similar to that for other wall-bounded flows. However, there is experimental evidence that the outer flow interacts with the near-wall flow to modify the generation of turbulence. Suggestions for further work include more comprehensive and sophisticated measurements of turbulent quantities in cylindrical boundary layers as well as computational modeling.
Intermolecular [4 + 2]-cycloadditions of nitroalkenes with cyclic olefins. Transformations of cyclic nitronates

Nitrocyclohexene undergoes facile SnCl4-induced, [4 + 2]-cycloadditions with simple cycloalkenes to produce nitronates. The nitronates can be transformed sterospecifically into a number of other functional groups (alcohol, ketone, oxime, amine) by hydrolytic, reductive, and oxidative processes. The mechanism of the [4 + 2]-cycloaddition is believed to involve formation of a zwitterionic intermediate which can collapse via competing pathways to form the observed products. 1,3-Dipolar cycloadditions of the nitronates are described.
Total synthesis of curacin A

Curacin A (1) was synthesized in a convergent manner. The key steps were (1) a Julia coupling to establish the stereochemistry of the C(7–10) diene, (2) a Wittig reaction to establish the stereochemistry of the C(3–4) alkene, and (3) a dehydrative cyclization to form the thiazoline ring system.
Canonical piecewise linear network for nonlinear filtering and its application to blind equalization

Abstract Canonical piecewise linear structures provide a desirable compromise between the approximation ability of nonlinear models and the efficiency and theoretical accessibility of the linear domain, and they reduce the parameter storage requirement of piecewise linear models considerably by employing a global linear representation. We first study the representation and approximation ability of CPL network and show that we can always construct a partition for which a CPL representation exists, and that we can approximate any given continuous nonlinear mapping with a CPL network. We then present application of CPL network to blind equalization, show the ability of CPL equalizer to achieve blind equalization of a nonlinear channel, specifically, we show that if the distribution of the equalizer output is the same as that of the input to the channel, then the channel and equalizer combination is identity except for a sign and a delay factor. We also present experimental results to show the successful application of CPL filter to blind equalization.
An Independence Relation for Sets of Secrets

A relation between two secrets, known in the literature as nondeducibility, was originally introduced by Sutherland. We extend it to a relation between sets of secrets that we call independence. This paper proposes a formal logical system for the independence relation, proves the completeness of the system with respect to a semantics of secrets, and shows that all axioms of the system are logically independent.
Effective typestate verification in the presence of aliasing

This article addresses the challenge of sound typestate verification, with acceptable precision, for real-world Java programs. We present a novel framework for verification of typestate properties, including several new techniques to precisely treat aliases without undue performance costs. In particular, we present a flow-sensitive, context-sensitive, integrated verifier that utilizes a parametric abstract domain combining typestate and aliasing information. To scale to real programs without compromising precision, we present a staged verification system in which faster verifiers run as early stages which reduce the workload for later, more precise, stages.We have evaluated our framework on a number of real Java programs, checking correct API usage for various Java standard libraries. The results show that our approach scales to hundreds of thousands of lines of code, and verifies correctness for 93p of the potential points of failure.
First and second kind paraorthogonal polynomials and their zeros

Given a probability measure @m with infinite support on the unit circle @?D={z:|z|=1}, we consider a sequence of paraorthogonal polynomials h"n(z,@l) vanishing at z=@l where @l@?@?D is fixed. We prove that for any fixed z"0@?supp(d@m) distinct from @l, we can find an explicit @r>0 independent of n such that either h"n or h"n"+"1 (or both) has no zero inside the disk B(z"0,@r), with the possible exception of @l. Then we introduce paraorthogonal polynomials of the second kind, denoted s"n(z,@l). We prove three results concerning s"n and h"n. First, we prove that zeros of s"n and h"n interlace. Second, for z"0 an isolated point in supp(d@m), we find an explicit radius @r@? such that either s"n or s"n"+"1 (or both) have no zeros inside B(z"0,@r@?). Finally, we prove that for such z"0 we can find an explicit radius such that either h"n or h"n"+"1 (or both) has at most one zero inside the ball B(z"0,@r@?).
Public-private technology R&D partnerships: lessons from US partnership for a new generation of vehicles

Government-industry RD it increased the profile of advanced technology opportunities; and it led to better working relationships between the federal government and automakers. It also indirectly led to a technology advancement - by inspiring more aggressive investments by European and Japanese automakers that, in turn, through a boomerang effect, inspired US automakers to do likewise. It is a success in the sense that both sets of partners are pleased. But has it served the public interest? Has it led to the best investment of government R&D funds and has it accelerated the commercialization of socially beneficial technologies? The answers to these latter questions are still uncertain.
Statistical Modeling of Monetary Policy and Its Effects

The science of economics has some constraints and tensions that set it apart from other sciences. One reflection of these constraints and tensions is that, more than in most other scientific disciplines, it is easy to find economists of high reputation who disagree strongly with one another on issues of wide public interest. This may sug gest that economics, unlike most other scientific disciplines, does not really make progress. Its theories and results seem to come and go, always in hot dispute, rather than improving over time so as to build an increasing body of knowledge. There is some truth to this view; there are examples where disputes of earlier decades have been not so much resolved as replaced by new disputes. But though econom ics progresses unevenly, and not even monotonically, there are some examples of real scientific progress in economics. This essay describes one—the evolution since around 1950 of our understanding of how monetary policy is determined and what its effects are. The story described here is not a simple success story. It describes an ascent to higher ground, but the ground is still shaky. Part of the purpose of the essay is to remind readers of how views strongly held in earlier decades have since been shown to be mistaken. This should encourage continuing skepticism of consensus views and motivate critics to sharpen their efforts at looking at new data, or at old data in new ways, and generating improved theories in the light of what they see. We will be tracking two interrelated strands of intellectual effort: the methodol ogy of modeling and inference for economic time series, and the theory of policy influences on business cycle fluctuations. The starting point in the 1950s of the the ory of macroeconomic policy was Keynes's analysis of the Great Depression of the 1930s, which included an attack on the Quantity Theory of money. In the 1930s, interest rates on safe assets had been at approximately zero over long spans of time, and Keynes explained why, under these circumstances, expansion of the money sup ply was likely to have little effect. The leading American Keynesian, Alvin Hansen, included in his (1952) book A Guide to Keynes a chapter on money, in which he explained Keynes's argument for the likely ineffectiveness of monetary expansion in a period of depressed output. Hansen concluded the chapter with, "Thus it is that modern countries place primary emphasis on fiscal policy, in whose service mone tary policy is relegated to the subsidiary role of a useful but necessary handmaiden." The methodology of modeling in the 1950s built on Jan Tinbergen's (1939) seminal book, which presented probably the first multiple-equation, statistically estimated economic time series model. His efforts drew heavy criticism. Keynes
An Expert System for Processing Uncorrelated Satellite Tracks

Abstract : Through an array of ground based radar sights and optical cameras, the United States military tracks objects in near and far Earth orbit. The sensors provide epoch and ephemeris information that is used to update a database of known objects. While a majority of the sensor observations are matched to their corresponding satellites, a small percentage are beyond the capabilities of current software and can not be correlated. These uncorrelated targets, UCT's, must be manually fitted by orbital analysts in a labor intensive process. As an alternative to this human intervention, the use of artificial intelligence techniques to augment the present computer code was explored. Specifically, an expert system for processing UCT's at the Naval Space Surveillance Command was developed. Rules were generated through traditional knowledge engineering methods and by a novel application of machine learning. The initial results are very good with the operational portions of the system matching the performance of the experts with an accuracy of 99%. Although not yet complete, the code developed in this research definitely shows the potential of using artificial intelligence to process UCT'S.