cssi/SciSciGPT-SciSciNet huggingface dataset:
Tetrasubstituted Olefins through the Stereoselective Catalytic Intermolecular Conjugate Addition of Simple Alkenes to α,β‐Unsaturated Carbonyl Compounds

Recent efforts in designing expeditious catalytic synthesis of tetrasubstituted olefins have in part been stimulated by growing needs for developing generally applicable methods for tamoxifen analogs (anti-breast cancer drug) as well as for photo-responsive organic materials and molecular devices.[1] A number of different catalytic methods have been developed to synthesize tetrasubstituted olefins, including: Suzuki-type Pd-catalyzed coupling reactions,[2] Ni- and Rh-catalyzed exocyclization methods,[3] Ni- and Pd-catalyzed nucleophilic coupling reactions of alkynes[4] and of alkyne-to-arylboronic acids,[5] Ti-catalyzed tandem alkyne-epoxide-ethyl acetate coupling,[6] and the ring-closing olefin metathesis by using Grubbs catalyst.[7] Though catalytic conjugate addition of alkenes has been recognized as a potentially powerful synthetic methodology in forming tetrasubstituted olefins, generally applicable conjugate addition of simple olefins to α,β-unsaturated carbonyl compounds has been hampered by lack of reactivity of the olefin substrates and due to the formation of homocoupling and other byproducts. Chelate-assisted C–H insertion[8] and cross coupling methods[9] are among the most notable advances in catalytic coupling reaction of enones with simple alkenes. Ni-catalyzed conjugate addition and allylic substitution reactions of simple alkenes have also been reported recently.[10] We recently discovered that the cationic complex [(C6H6)(CO)(PCy3)RuH]+BF4− (1) is a highly effective catalyst precursor for the coupling reactions of arylketones and alkenes involving C–H activation.[11] Herein we report a novel catalytic synthesis of tetrasubstituted olefins from the intermolecular conjugate addition reaction of simple olefins to α,β-unsaturated carbonyl compounds.
STELLAR ROTATION IN YOUNG CLUSTERS. II. EVOLUTION OF STELLAR ROTATION AND SURFACE HELIUM ABUNDANCE

We derive the effective temperatures and gravities of 461 OB stars in 19 young clusters by fitting the H gamma profile in their spectra. We use synthetic model profiles for rotating stars to develop a method to estimate the polar gravity for these stars, which we argue is a useful indicator of their evolutionary status. We combine these results with projected rotational velocity measurements obtained in a previous paper on these same open clusters. We find that the more massive B stars experience a spin-down as predicted by the theories for the evolution of rotating stars. Furthermore, we find that the members of binary stars also experience a marked spin-down with advanced evolutionary state due to tidal interactions. We also derive non-LTE-corrected helium abundances for most of the sample by fitting the He I lambda lambda 4026, 4387, 4471 lines. A large number of helium peculiar stars are found among cooler stars with T-eff < 23, 000 K. The analysis of the high-mass stars (8.5 M circle dot < M < 16 M circle dot) shows that the helium enrichment process progresses through the main-sequence (MS) phase and is greater among the faster rotators. This discovery supports the theoretical claim that rotationally induced internal mixing is the main cause of surface chemical anomalies that appear during the MS phase. The lower mass stars appear to have slower rotation rates among the low-gravity objects, and they have a large proportion of helium peculiar stars. We suggest that both properties are due to their youth. The low-gravity stars are probably pre-main-sequence objects that will spin up as they contract. These young objects very likely host a remnant magnetic field from their natal cloud, and these strong fields sculpt out surface regions with unusual chemical abundances.
Stingray envenomation: a retrospective review of clinical presentation and treatment in 119 cases

Stingray stings are common along coastal regions of this country and the world. The tail of the stingray contains a barbed stinger attached to a venom gland and contained within an integumentary sheath. During a sting, the stinger and sheath can become embedded in the soft tissue of the victim, and venom is injected into the wound. Stingray venom most often causes severe pain on contact, although the exact mechanism of toxicity is not certain. Hot water immersion of the stung extremity has been reported to be effective in relieving pain associated with the envenomation, but large studies of this therapy have not been performed. We retrospectively reviewed stingray stings presenting to our Emergency Department (ED) over an 8-year period. Cases were divided into acute (group 1, within 24 h of the sting) and subacute (group 2, 24 h or more after the sting) presentations. Charts were abstracted for information concerning the victim's history, physical examination, treatment, diagnostic imaging, and outcome, including the effectiveness of hot water immersion as analgesia, and use of antimicrobials. A total of 119 cases were identified and abstracted, 100 in group 1 and 19 in group 2. Of the group 1 patients initially treated with hot water immersion alone, 88% had complete relief of pain within 30 min without administration of any other analgesic. In the patients who initially received a dose of analgesic along with hot water immersion, none required a second dose of analgesics and all had complete pain relief before discharge. There were no adverse effects (such as thermal burns) with this therapy. Analysis of infectious complications in group 1 patients demonstrated a significant number of patients returning to the ED with wound infections when prophylactic antibiotics were not administered at initial presentation. Our findings suggest that hot water immersion was effective in decreasing or eliminating the pain associated with stingray envenomation in our series. Due to the high potential for bacterial contamination in these puncture wounds, standard antibiotic prophylaxis may be prudent. Although stingray barbs can be radio-opaque, radiography in our series failed to detect barbs or other foreign bodies in stung extremities, although no barbs or other stinger material were found on inspection of wounds.
Low-mass higgs bosons in the NMSSM and their LHC implications

We study the Higgs sector of the Next to Minimal Supersymmetric Standard Model (NMSSM) in light of the discovery of the SM-like Higgs boson at the LHC. We perform a broad scan over the NMSSM parameter space and identify the regions that are consistent with current Higgs search results at colliders. In contrast to the commonly studied “decoupling” scenario in the literature where the Minimal Supersymmetric Standard Model CP-odd Higgs boson mass is large m A ≫ m Z , we pay particular attention to the light Higgs states in the case when m A ≲ 2m Z . The Higgs bosons in the NMSSM, namely three CP-even states, two CP-odd states, and two charged Higgs states, could all be rather light, near or below the electroweak scale, although the singlet-like states can be heavier. The SM-like Higgs boson could be either the lightest CP-even scalar or the second lightest CP-even scalar, but is unlikely to be the heaviest scalar. These NMSSM parameter regions have unique properties and offer rich phenomenology. The decay branching fractions for the SM-like Higgs boson may be modified appreciably. The correlations of γγ/V V and $ {VV \left/ {{b\overline{b}}} \right.} $ can be substantially altered. The new Higgs bosons may be readily produced at the LHC and may decay to non-standard distinctive final states, most notably a pair of Higgs bosons when kinematically accessible. We evaluate the production and decay of the Higgs bosons and comment on further searches at the LHC to probe the Higgs sector of the NMSSM.
A controls laboratory program with an accent on system identification

A sequence of laboratories is presented which have been designed to maximize student involvement in the design as well as execution of the laboratory exercises. The student works quite independently, starting with the simplest plant and control model, and a relatively structured identification experiment, controller design and performance assessment. The student moves to self-designed system identification and controller design. The cap stone of the course is a competitive controls application which challenges the students command of the theoretical tools as well as thoroughness and accuracy of experimental technique.
Evolution of high-redshift quasars

The discovery of luminous quasars at z > 6 indicates the existence billion-solar-mass black holes at the end of reionization epoch. These quasars provide the best probes of the early growth of supermassive black holes in the universe and the relation between the formation of early galaxies and black holes. With the advent of the Sloan Digital Sky Survey and other large area surveys, about 1000 quasars have been discovered at z > 4, including >50 at z > 5 and nine at z > 6. I here review the recent observational results studies of the highest redshift quasars, including the evolution of quasar density and luminosity function, the evolution of spectral properties and chemical enrichment history, distribution of black hole masses and properties of quasar environment and host galaxies at high redshift.
Weak Chirality in Ordered Dna Phases

Abstract Recent experimentsl on aligned DNA show hexatic order with no sign of macroscopic chirality. I make the analogy between smectic liquid crystals and chiral hexatics and show how the absence of chirality cannot occur in a thermodynamic phase of chiral molecules. In addition, I discuss the microscopic origin of chiral mesophases in liquid crystals and show that within the context of central forces between “atoms” on “molecules”, ciral interactions can occur only there are biaxial correlations between the mesogens. Weak biaxial correlations can therefore lead to small cholesteric pitches.
Evolution of marine sedimentation in the Bering Sea since the Pliocene

Sediment of the Bering Sea, derived mainly from biogenic, glaciomarine, and, secondarily, riverine sources, reflects the history of oceanographic changes within the basin and climatic changes on the adjacent continents. Integrated Ocean Drilling Program (IODP) Expedition 323 recovered cores that reveal the evolution of sedimentation in the Bering Sea over the past 5 m.y., a period that includes globally significant events such as the early Pliocene warm period, the onset of extensive Northern Hemisphere glaciation, and the Pleistocene glacial-interglacial and millennial-scale climate cycles. To begin to understand the Bering Sea regional response to and role in these global climate change events, we examined the sedimentary constituents of Expedition 323 sites U1339, U1343, and U1344 on the Bering Slope, and U1340 and U1341 on Bowers Ridge. New particle size and petrographic analyses, combined with shipboard lithostratigraphic and physical property data, are used to characterize sediment types and texture and its distribution through space and time. The sediment comprises mainly two components, opaline diatom valves and siliciclastic grains (mainly clay and fine silt size). Approximately 40% of the variance in particle size can be explained by the abundance and preservation of diatom valves, a rough indicator of biogenic opal productivity. Particle size data indicate that productivity was generally higher during interglacials compared to glacials, and higher during the Pliocene warm period, decreasing as Northern Hemisphere glaciation intensified ∼3 m.y. ago. Although the abundance of diatoms in the sediment varied, diatom ooze and diatom mud are the dominant lithologies at Bowers Ridge, indicating that there was a persistent supply of diatoms to the sediment in the open Bering Sea during the past 5 m.y. This study provides a comprehensive view of sediment types and sedimentation processes; future work should be aimed at validating our interpretations of past changes in productivity and siliciclastic sedimentation mechanisms with multiple additional proxies.
Tau Functions Associated to Pseudodifferential Operators of Several Variables

Pseudodifferential operators of several variables are formal Laurent series in the formal inverses of ∂1 ,...,∂ n with ∂i = d/dxi for 1 ≤ i ≤ n. As in the single variable case, Lax equations can be constructed using such pseudodifferential operators, whose solutions can be provided by Baker functions. We extend the usual notion of tau functions to the case of pseudodifferential operators of several variables so that each Baker function can be expressed in terms of the corresponding tau function.
EVIDENCE FOR A PARSEC-SCALE JET FROM THE GALACTIC CENTER BLACK HOLE: INTERACTION WITH LOCAL GAS

Despite strong physical reasons that they should exist and decades of searching, jets from the Galactic center black hole, Sgr A*, have not yet been convincingly detected. Based on high-resolution Very Large Array images and ultra-deep imaging-spectroscopic data produced by the Chandra X-ray Observatory, we report new evidence for the existence of a parsec-scale jet from Sgr A*, by associating a linear feature G359.944–0.052, previously identified in X-ray images of the Galactic center, with a radio shock front on the Eastern Arm of the Sgr A West H II region. We show that the shock front can be explained in terms of the impact of a jet having a sharp momentum peak along the Galaxy's rotation axis, whereas G359.944–0.052, a quasi-steady feature with a power-law spectrum, can be understood as synchrotron radiation from shock-induced ultra-relativistic electrons cooling in a finite post-shock region downstream along the jet path. Several interesting implications of the jet properties are discussed.
Exploring energy-time entanglement Using geometric phase

Using the photons produced by parametric down-conversion, we report an experimental observation of a violation of the Bell inequality for energy and time based purely on the geometric phases of the downconverted photons.
WELFARE SPENDING AND MORTALITY RATES FOR THE ELDERLY BEFORE THE SOCIAL SECURITY ERA

Abstract We analyze the impact of the original means-tested old-age assistance (OAA) programs on the health of the elderly prior to the first Social Security pension payments. Before 1935 a number of states had enacted their own OAA laws. After 1935 the federal government began offering matching grants and thus stimulated the adoption of OAA programs by the states. A new panel data set of 75 cities for each year between 1929 and 1938 combines mortality rates for older age groups with three measures of the OAA programs, spending on non-age-specific relief and a rich set of correlates. The data are analyzed using difference-in-difference-in-difference and instrumental variables methods. Our results suggest that old-age assistance in the 1930s had little impact on the death rate of the elderly. Our sense is that the OAA programs in the 1930s transferred the elderly from general relief programs without necessarily increasing the resources available to them.
Remote Hydroxylation through Radical Translocation and Polar Crossover

Mild conditions are reported for the hydroxylation of aliphatic CH bonds through radical translocation, oxidation to carbocation, and nucleophilic trapping with H2O. This remote functionalization employs fac-[Ir(ppy)3] together with Tzo sulfonate esters and sulfonamides to facilitate the site-selective replacement of relatively inert CH bonds with the more synthetically useful COH group. The hydroxylation of a range of substrates and the methoxylation of two substrates through 1,6- and 1,7-hydrogen-atom transfer are demonstrated. In addition, a synthesis of the antidepressant fluoxetine using remote hydroxylation as a key step is presented.
Limiter Control of a Chaotic RF Transistor Oscillator

We report experimental control of chaos in an electronic circuit at 43.9 MHz, which is the fastest chaos control reported in the literature to date. Limiter control is used to stabilize a periodic orbit in a tuned collector transistor oscillator modified to exhibit simply folded band chaos. The limiter is implemented using a transistor to enable monitoring the relative magnitude of the control perturbation. A plot of the relative control magnitude versus limiter level shows a local minimum at period-1 control, thereby providing strong evidence that the controlled state is an unstable periodic orbit (UPO) of the uncontrolled system.
Emstar: A software environment for developing and deploying heterogeneous sensor-actuator networks

Recent work in wireless embedded networked systems has followed heterogeneous designs, incorporating a mixture of elements from extremely constrained 8- or 16-bit “Motes” to less resource-constrained 32-bit embedded “Microservers.”Emstar is a software environment for developing and deploying complex applications on such heterogeneous networks. Emstar is designed to leverage the additional resources of Microservers by trading off some performance for system robustness in sensor network applications. It enables fault isolation, fault tolerance, system visiblity, in-field debugging, and resource sharing across multiple applications.In order to accomplish these objectives, Emstar is designed to run as a multiprocess system and consists of libraries that implement message-passing IPC primitives, services that support networking, sensing, and time synchronization, and tools that support simulation, emulation, and visualization of live systems, both real and simulated. We evaluate this work by discussing the Acoustic ENSBox, a platform for distributed acoustic sensing that we built using Emstar. We show that by leveraging existing Emstar services, we are able to significantly reduce development time while achieving a high degree of robustness. We also show that a sample application was developed much more quickly on this platform than it would have been otherwise.
Preserving and ensuring long-term access to digitally born legal information

Written laws, records and legal materials form the very foundation of a democratic society. Lawmakers, legal scholars and everyday citizens alike need, and are entitled, to access the current and historic materials that comprise, explain, define, critique and contextualize their laws and legal institutions. The preservation of legal information in all formats is imperative. Thus far, the twenty-first century has witnessed unprecedented mass-scale acceptance and adoption of digital culture, which has resulted in an explosion in digital information. However, digitally born materials, especially those that are published directly and independently to the Web, are presently at an extremely high risk of permanent loss. Our legal heritage is no exception to this phenomenon, and efforts must be put forth to ensure that our current body of digital legal information is not lost. The authors explored the role of the United States law library community in the preservation of digital legal information. Through an online survey of state and academic law library directors, it was determined that those represented in the sample recognize that digitally born legal materials are at high risk for loss, yet their own digital preservation projects have primarily focused upon the preservation of digitized print materials, rather than digitally born materials. Digital preservation activities among surveyed libraries have been largely limited by a lack of funding, staffing and expertise; however, these barriers could be overcome by collaboration with other institutions, as well as participation in a large-scale regional or national digital preservation movement, which would allow for resource-sharing among participants. One such collaborative digital preservation program, the Chesapeake Project, is profiled in the article and explored as a collaborative effort that may be expanded upon or replicated by other institutions and libraries tackling the challenges of digital preservation.
The Distributional Impacts of Indonesia's Financial Crisis on Household Welfare : A 'Rapid Response' Methodology

Analyzing the distributional impacts of economic crises is an ever more pressing need. If policymakers are to intervene to help those most adversely affected, they need to identify those who have been hurt most and estimate the magnitude of the harm they have suffered. They must also respond in a timely manner. This article develops a simple methodology for measuring these effects and applies it to analyze the impact of the Indonesian economic crisis on household welfare. Using only pre-crisis household information, it estimates the compensating variation for Indonesian households following the 1997 Asian currency crisis and then explores the results with flexible nonparametric methods. It finds that virtually every household was severely affected, although the urban poor fared the worst. The ability of poor rural households to produce food mitigated the worst consequences of the high inflation. The distributional consequences are the same whether or not households are permitted to substitute toward relatively cheaper goods. Households with young children may have suffered disproportionately large adverse effects.
Iron-catalyzed enediene carbocyclizations. The total synthesis of (−)-gibboside

The first total synthesis of (−)-gibboside is reported. The route features a novel iron-catalyzed carbocyclization as the key step for the construction of the cis,trans,cis-tetrasubstituted cyclopentane core.
The Influence of European Pollution on Ozone in the Near East and Northern Africa

We present a modeling study of the long-range transport of pollution from Europe, showing that European emissions regularly elevate surface ozone by as much as 20 ppbv in summer in northern Africa and the Near East. European emissions cause 50-150 additional violations per year (i.e. above those that would occur without European pollution) of the European health standard for ozone (8-h average greater than 120 micrograms per cubic meters or approximately 60 ppbv) in northern Africa and the Near East. We estimate that European ozone pollution is responsible for 50 000 premature mortalities globally each year, of which the majority occurs outside of Europe itself, including 37% (19 000) in northern Africa and the Near East. Much of the pollution from Europe is exported southward at low altitudes in summer to the Mediterranean Sea, northern Africa and the Near East, regions with favorable photochemical environments for ozone production. Our results suggest that assessments of the human health benefits of reducing ozone precursor emissions in Europe should include effects outside of Europe, and that comprehensive planning to improve air quality in northern Africa and the Near East likely needs to address European emissions.
Palladium(0)-catalyzed amination, Stille coupling, and Suzuki coupling of electron-deficient aryl fluorides.

The amination of 2-fluoronitrobenzene was Pd(0) catalyzed at 65 °C in DMF, and the effectiveness of the catalysis was ligand-dependent. Among the five catalyst systems investigated, Pd(PPh3)4 was the most effective catalyst. The control experiments revealed that Pd(OAc)2 or PPh3 was not responsible for the catalysis. 4-Fluoro-3-nitro-benzonitrile and 4-fluoro-3-nitro-benzaldehyde also underwent Stille coupling and Suzuki coupling in the presence of Pd(PPh3)4, and the reactions afforded the coupling products in 28−86% yields. The control experiments showed no sign of reaction in the absence of palladium. These results were in agreement with the oxidative addition/reductive elimination pathway, where the oxidative addition could conceivably proceed via the SNAr mechanism.
Higher education subsidies and heterogeneity: a dynamic analysis

Abstract In this paper, we develop a simple dynamic general equilibrium framework to address the effects of increasing higher education subsidies in the US, from their already substantial levels, on inequality, welfare, and efficiency. We focus on three policies. The first is a tax and subsidy scheme that ensures that the parental decision to send a child to college is independent of income. Such a policy decreases the efficiency of the utilization of education resources, while the welfare gain is minimal. The second policy maximizes the fraction of college educated labor. This results in a large drop in the above-mentioned efficiency with little or no welfare gain. The third is the provision of merit-based aid to the poor as opposed to purely need-based aid. This policy can increase education efficiency with little decrease in welfare. Based on these experiments, we conclude that the case for further increases in higher education subsidies might have been overstated.
Loop gain measurement of paralleled dc-dc converters with average-current-sharing control

Paralleled operation of dc-dc converters is widely used in today's distributed power systems. Special control circuitry is usually necessary to ensure current sharing among the paralleled modules. The average-current-sharing control method is very popular due to its simple implementation and good performance. Although the analysis and design of the average current-sharing control were presented in the past, a loop gain measurement technique has not been published. This paper presents a practical loop gain measurement technique which uses two excitation sources. Measured and theoretical data are compared to verify the proposed technique.
Efficient informative sensing using multiple robots

The need for efficient monitoring of spatio-temporal dynamics in large environmental applications, such as the water quality monitoring in rivers and lakes, motivates the use of robotic sensors in order to achieve sufficient spatial coverage. Typically, these robots have bounded resources, such as limited battery or limited amounts of time to obtain measurements. Thus, careful coordination of their paths is required in order to maximize the amount of information collected, while respecting the resource constraints. In this paper, we present an efficient approach for near-optimally solving the NP-hard optimization problem of planning such informative paths. In particular, we first develop eSIP (efficient Single-robot Informative Path planning), an approximation algorithm for optimizing the path of a single robot. Hereby, we use a Gaussian Process to model the underlying phenomenon, and use the mutual information between the visited locations and remainder of the space to quantify the amount of information collected. We prove that the mutual information collected using paths obtained by using eSIP is close to the information obtained by an optimal solution. We then provide a general technique, sequential allocation, which can be used to extend any single robot planning algorithm, such as eSIP, for the multi-robot problem. This procedure approximately generalizes any guarantees for the single-robot problem to the multi-robot case. We extensively evaluate the effectiveness of our approach on several experiments performed infield for two important environmental sensing applications, lake and river monitoring, and simulation experiments performed using several real world sensor network data sets.
Improved cyclopropanation activity of histidine-ligated cytochrome P450 enables the enantioselective formal synthesis of levomilnacipran.

Engineering enzymes capable of modes of activation unprecedented in nature will increase the range of industrially important molecules that can be synthesized through biocatalysis. However, low activity for a new function is often a limitation in adopting enzymes for preparative-scale synthesis, reaction with demanding substrates, or when a natural substrate is also present. By mutating the proximal ligand and other key active-site residues of the cytochrome P450 enzyme from Bacillus megaterium (P450-BM3), a highly active His-ligated variant of P450-BM3 that can be employed for the enantioselective synthesis of the levomilnacipran core was engineered. This enzyme, BM3-Hstar, catalyzes the cyclopropanation of N,N-diethyl-2-phenylacrylamide with an estimated initial rate of over 1000 turnovers per minute and can be used under aerobic conditions. Cyclopropanation activity is highly dependent on the electronic properties of the P450 proximal ligand, which can be used to tune this non-natural enzyme activity.
Catalytic Hydrogen‐Mediated Cross‐Coupling of Enones and Carbonyl Compounds: Aldol Condensation by Hydrogenation

Catalytic hydrogenation of enones and enals in the presence of aldehyde and ketone partners results in the formation of aldol products. A key feature of such hydrogen-mediated C−C bond formations relates to the heterolytic activation of elemental hydrogen by cationic rhodium(I) complexes, that enables monohydride-based catalytic cycles for which direct alkyl-hydrogen reductive elimination pathways are disabled. Here, a concise overview of catalytic hydrogen-mediated aldol condensation is presented. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
A Fiscal Theory of Currency Crises

An exchange rate crisis is caused when the fiscal authority lets the present value of primary surpluses, inclusive of seigniorage, deviate from the value of government debt at the pegged exchange rate. In the absence of long-term government bonds, the exchange rate collapse must be instantaneous. With long-term government bonds, the collapse can be delayed at the discretion of the monetary authority. Fiscal policy is responsible for the inevitability of a crisis, while monetary policy determines its characteristics, that is, the timing of the crisis and the magnitude of exchange rate depreciation.
Mega-Sporting Events in Developing Nations: Playing the Way to Prosperity?

Supporters of mega-sporting events such as the World Cup and Olympics claim that these events attract hoards of wealthy visitors and lead to lasting economic benefits for the host regions. Developing countries have become increasingly vocal in demanding a share of the economic benefits of these international games. The specialized infrastructure and operating expenses required to host these events, however, can be substantial. Independent researchers have found that boosters’ projections of the economic impact of sporting events exaggerate the true economic impact of these competitions, and these events are an even worse investment for developing countries than for industrialized nations.(This abstract was borrowed from another version of this item.)
Edgeworth Price Cycles and Intertemporal Price Discrimination

In a retail gasoline market exhibiting Edgeworth Price Cycles, prices change asymmetrically with many small decreases interrupted by occasional large increases. The result is a de facto menu of prices from which consumers can choose based on exactly when they buy. This article introduces four classes of purchase timing strategies designed to systematically shift consumer purchases towards the cycle troughs. It shows in the study market of Toronto, Canada, the monetary gains to consumers from optimized timing strategies are as high as 3.9%. Markups earned from these consumers fall up to 82%. In spite of the gains from timing strategies, surprisingly few consumers use them. Evidence is presented that a main reason is that consumers are not well informed about the cycles. Policy implications are discussed.
Uncrossed bridges: Islam, feminism and secular democracy

In this article I review two contrasting approaches to Muslim women’s rights: those that want Muslims to secularize the Qur’an as the precondition for getting rights and those that emphasize the importance of a liberatory Qur’anic hermeneutics to Muslim women’s struggles for rights and equality. As examples of the former, I take the works of Nasr Abu Zayd and Raja Rhouni and, of the latter, my own. In addition to joining the debates on Muslim women’s rights, this exercise is meant to illustrate that secular attempts to undermine Islam also undermine the prospects for rights and democracy in Muslim societies. In fact, I see the secular project in Muslim societies as a form of self-harm. Lastly, I revisit Antonio Gramsci’s critique of democracy as a way to query the title of the Istanbul Seminars, ‘The Promises of Democracy’.
SOLID-STATE CONFORMATIONS OF MEDIUM-SIZED-RING PHOSPHORUS HETEROCYCLES: X-RAY CRYSTAL STRUCTURES OF TWO NORBORNENE-FUSED 1,3,2-DIOXAPHOSPHEPANES WITH EQUATORIALLY DISPOSED SUBSTITUENTS ON PHOSPHORUS

Abstract The seven-membered-ring phosphorus heterocycles, frans-5,6-(endo,endo-2′,3′-bicyclo[2.2.1]hept-5′-eno)-2-oxo-2-phenoxy-1,3,2-dioxaphosphepane. trans-1, and trans-5,6-(endo,endo-2′,3′-bicyclo-[2.2.1]hept-5′-eno)-2-oxo-2-phenyl-1,3,2-dioxaphosphepane, trans-2, have been synthesized and the crystal and molecular structures of the compounds determined from single-crystal X-ray studies. Compound trans-1 crystallizes in the monoclinic space group P21/c with four molecules per unit cell of dimensions a=6.275(2) A. b=19.419(7) A, c=11.363(2) A, and β=90.89(2)°. Full-matrix least-squares refinement using 2317 unique reflections having 2.5° ≤ 28 ≤ 49.0° and 1 ≤ 3 σ (1) converged at R=0.0543 and Rw=0.0650. Compound trans-2 crystallizes in the orthorhombic space group P212121 with four molecules per unit cell of dimensions a=9.702(3) A, b=11.296(4) A, and c=12.605(4) A. Full-matrix least-squares refinement using 1862 unique reflections having 4.0° ≤ 20 ≤ 50.0° and 1 ≥ 2.5 σ (I) converged at R=0.040 and Rw =0...
Underpaid or Overpaid? Wage Analysis for Nurses Using Job and Worker Attributes

The nursing labor market presents an apparent puzzle. Hospitals report chronic shortages, yet standard wage analysis shows that nursing wages have increased over time and greatly exceed those received by other college-educated women. This paper addresses this puzzle. Data from the Current Population Survey (CPS) are matched with detailed job content descriptors from the Occupational Information Network (O*NET). Nursing jobs require higher levels of skills and more difficult working conditions than do jobs for other college educated workers. A standard CPS-only wage regression shows a registered nurse (RN) wage advantage of .22 log points compared to a pooled male/female group of college-educated workers. Control for O*NET job attributes reduces the RN gap to .08, while an arguably preferable nonparametric estimator produces a wage gap estimate close to zero. We conclude that nurses receive compensation close to long-run opportunity costs, narrowing if not resolving the RN wage-shortage puzzle.
Turán Problems on Non-Uniform Hypergraphs

A non-uniform hypergraph $H=(V,E)$ consists of a vertex set $V$ and an edge set $E\subseteq 2^V$; the edges in $E$ are not required to all have the same cardinality. The set of all cardinalities of edges in $H$ is denoted by $R(H)$, the set of edge types. For a fixed hypergraph $H$, the Turan density $\pi(H)$ is defined to be $\lim_{n\to\infty}\max_{G_n}h_n(G_n)$, where the maximum is taken over all $H$-free hypergraphs $G_n$ on $n$ vertices satisfying $R(G_n)\subseteq R(H)$, and $h_n(G_n)$, the so called Lubell function, is the expected number of edges in $G_n$ hit by a random full chain. This concept, which generalizes the Turan density of $k$-uniform hypergraphs, is motivated by recent work on extremal poset problems. The details connecting these two areas will be revealed in the end of this paper. Several properties of Turan density, such as supersaturation, blow-up, and suspension, are generalized from uniform hypergraphs to non-uniform hypergraphs. Other questions such as "Which hypergraphs are degenerate?" are more complicated and don't appear to generalize well. In addition, we completely determine the Turan densities of $\{1,2\}$-hypergraphs.
Ill Communication: Technology, distraction & student performance

This paper investigates the impact of schools banning mobile phones on student test scores. By surveying schools in four English cities regarding their mobile phone policies and combining it with administrative data, we adopt a difference in differences (DID) strategy, exploiting variations in schools' autonomous decisions to ban these devices, conditioning on a range of student characteristics and prior achievement. We find that student performance in high stakes exams significantly increases post ban, by about 0.07 standard deviations on average. These increases in performance are driven by the lowest-achieving students. This suggests that the unstructured presence of phones has detrimental effects on certain students and restricting their use can be a low-cost policy to reduce educational inequalities.
High temperature superconducting current leads for cryogenic apparatus

Abstract The use of high temperature superconductors (HTSC) for cryostat current leads has been analysed for operation between liquid helium and liquid nitrogen temperatures in the conduction-cooled and vapour-cooled cases. Present fabrication methods are sufficient to produce such leads for most known applications. Thermophysical data suggest that performance of leads of HTSC operated in the normal state is nearly as good as that of pure metal leads. If leads of HTSC are optimized for the normal state and then operated in the superconducting state, helium boil-off can be reduced by about a factor of two. For leads longer than the normal state optimum, the helium boil-off can be reduced further, but the system must be guarded against thermal runaway. For temperature perturbations, the lead may enter a metastable state where a large fraction of the length remains normal. For current or magnetic field perturbations, the lead may enter a hybrid partially superconducting state in which the effective resistivity is ≈0.1 that of the normal state. In designs for these latter cases, the helium boil-off is greatly reduced below that for pure metal leads. Operation at presently obtainable current densities of 100–1000 A cm−2 results in adequate steady state cooling and thermal stability for most designs.
Characters of Fundamental Representations of Quantum Affine Algebras

We give closed formulae for the q-characters of the fundamental representations of the quantum loop algebra of a classical Lie algebra, in terms of a family of partitions satisfying some simple properties. We also give the multiplicities of the eigenvalues of the imaginary subalgebra in terms of these partitions.
The Optimal Time to File for Social Security Benefits

Under current Social Security rules, a newly retired worker can affect the age structure of benefits that he or she will receive by choosing when to file for a claim for benefits: the longer the claim is deferred, the greater the monthly benefit will be. This article examines the alternatives available to individuals and presents a life cycle model of retirement planning that determines the optimal time to file for benefits. The model is applied with the Social Security rules for 1998 and with an idealized system in which all adjustments to benefits are actuarially fair. It is shown that in many cases individuals will choose to file for benefits several years after retirement instead of immediately. The gain achieved by doing this can be substantial.
Using dynamic holography for iron fibers with submicron diameter and high velocity

A divergent laser beam was used to record holograms of moving iron fibers with submicron diameter (0.5 μm) and high velocity (125 m/s). Analysis based on geometric optics is used to derive the magnification factors for recording and reconstruction. Experimental results consisting of single-shot holograms of fast-moving fibers are presented. The divergent laser beam technique can be used for dynamic measure of particle size and fiber orientation distribution.
New Challenges to the Rationality Assumption

In contrast to logical criteria of rationality, which can be assessed entirely by reference to the system of preferences, substantive criteria of rational choice refer to an independent evaluation of the outcomes of decisions. One of these substantive criteria is the experienced hedonic utility of outcomes. Research indicates that people are myopic in their decisions, may lack skill in predicting their future tastes, and can be led to erroneous choices by fallible memory and incorrect evaluation of past experiences. Theoretical and practical implications of these challenges to the assumption of economic rationality are discussed.
Misogyny in Rap Music: A Content Analysis of Prevalence and Meanings

Rap music has a reputation for being misogynistic, but surprisingly little research has systematically investigated this dimension of the music. This study assesses the portrayal of women in a representative sample of 403 rap songs. Content analysis identified five gender-related themes in this body of music—themes that contain messages regarding ‘‘essential’’ male and female characteristics and that espouse a set of conduct norms for men and women. Our analysis situates rap music within the context of larger cultural and music industry norms and the local, neighborhood conditions that inspired this music in the first place.
Thin film magnetism

New developments in thin-film magnetism are reviewed with an emphasis on the ultrathin regime. Relatively simple metallic systems in overlayer, sandwich, and superlattice configurations are covered. Sample fabrication, characterization, and magnetic measurement techniques are outlined, highlighting some of the more modern experimental innovations. Current issues and advances that demonstrate the symbiotic relationship between experiment and theory are examined, including surface magnetic anisotropy, two-dimensional critical behavior, the creation of metastable phases by epitaxy, and phenomena associated with coupled magnetic layers. A brief account is given of the impact of the various developments on applications. >
Synthesis of the liposidomycin diazepanone

Abstract Acrolein and two sarcosines are combined to give the diazepanone substructure of the liposidomycin nucleoside antibiotics. Conformational analysis of the substituted diazepanone ring is presented.
Conflicts and Choices in Biodiversity Preservation

The purpose of this article is to examine the preservation of biodiversity as an economic problem. Using a very simple prototype model, the authors discuss how to include diversity in the objective function and how to develop a simple cost-benefit ranking criterion for ordering priorities. Then they analyze data on endangered species preservation decisions in the United States to shed light on the conformity of theory with practice. A basic theme is that the core issue in biodiversity preservation today is the fuzziness of the objective function.
Unscrambling Africa: Regional Requirements for Achieving Food Security

Africa has inherited highly arbitrary political borders that vastly complicate current efforts to accelerate agricultural growth and reduce hunger. By partitioning agro-ecological zones and natural market sheds, current borders serve as barriers, hampering agricultural technology transfer, hindering agricultural trade and dampening incentives for farmers and agribusinesses to invest in Africa's many regional bread-basket zones. Feasible solutions revolve around neutralising these deleterious effects through regional scientific networks and corridor development programmes.
Effects of treatment on the treated: identification and generalization

Many applications of causal analysis call for assessing, retrospectively, the effect of with-holding an action that has in fact been implemented. This counterfactual quantity, sometimes called "effect of treatment on the treated," (ETT) have been used to to evaluate educational programs, critic public policies, and justify individual decision making. In this paper we explore the conditions under which ETT can be estimated from (i.e., identified in) experimental and/or observational studies. We show that, when the action invokes a singleton variable, the conditions for ETT identification have simple characterizations in terms of causal diagrams. We further give a graphical characterization of the conditions under which the effects of multiple treatments on the treated can be identified, as well as ways in which the ETT estimand can be constructed from both interventional and observational distributions.
Bank Privatization in Sub-Saharan Africa: The Case of Uganda Commercial Bank

Previous empirical analyses have found that bank privatizations are more successful when the government fully relinquishes control, when the bank is privatized to a strategic investor, and when foreign-owned banks are allowed to participate in the bidding. The privatization of Uganda Commercial Bank (UCB) to the South African bank Stanbic met all these criteria, suggesting that it is a likely candidate for success. But other features suggest reasons for caution: UCB dominated the Ugandan banking sector prior to privatization and the institutional environment in Uganda was less favorable than in many of the middle-income countries looked at in earlier empirical studies. Despite these concerns, the privatization appears to have been relatively successful. The portfolio of the privatized bank, which was cleaned prior to sale, remains relatively strong and profitability and credit growth are now on par with other Ugandan banks. Though market segmentation remains a concern since Stanbic faces little or no direct competition in many remote areas, some early results suggest that access to credit has improved for some hard-to-serve groups.
The Effects of Audit Quality and Consequence Severity on Juror Evaluations of Auditor Responsibility for Plaintiff Losses

This study investigates whether providing higher quality audits increases auditors' chances of avoiding legal liability. Negligence rules hold auditors responsible for plaintiff losses only when the quality of the audit provided fails to meet standards of care. The results of my experiment suggest that the ex post observed consequences of audit failure can affect the standards of care to which jurors hold auditors. Specifically, participants serving in the role of jurors assessed higher standards of care for auditors when the consequences of audit failure were more severe. Furthermore, when the consequences of audit failure were more severe, participants' evaluations of the auditor did not depend on the quality of the audit provided—auditors who provided higher quality audits were evaluated just as negatively as those who provided lower quality audits. In contrast, when audit failure led to only moderately negative consequences, auditors who provided higher quality audits received more favorable evaluatio...
AN INTEGRATED HEURISTIC SCHEME FOR PARTIAL PARSE EVALUATION

GLR is a recently developed robust version of the Generalized LR Parser [Tomita, 1986], that can parse almost any input sentence by ignoring unrecognizable parts of the sentence. On a given input sentence, the parser returns a collection of parses that correspond to maximal, or close to maximal, parsable subjsets of the original input. This paper describes recent work on developing an integrated heuristic scheme for selecting the parse that is deemed "best" from such a collection. We describe the heuristic measures used and their combination scheme. Preliminary results from experiments conducted on parsing speech recognized spontaneous speech are also reported.
Non-perturbative improvement of bilinears in unquenched QCD

Abstract We describe how the improvement of quark bilinears generalizes from quenched to unquenched QCD, and discuss which of the additional improvement constants can be determined using Ward Identities.