cssi/SciSciGPT-SciSciNet huggingface dataset:
Paradoxical Embolism Interrupted

A 41 year-old African-American male presented with syncope preceded by shortness of breath at outside facility and transferred to us for management of extensive pulmonary embolism with unstable vital signs. Electrocardiogram showed sinus tachycardia with S1Q3T3 pattern. A transthoracic echocardiogram revealed a freely mobile strand like mass in the left atrium. A transoesophageal echocardiogram showed a very large freely mobile thrombus extending from a patent foramen ovale in to the left atrium. He underwent emergent surgery for the extraction of clot followed by thromboembolectomy from both pulmonary arteries. He made a remarkable recovery and was discharged after seven days of hospital stay.
Temporal Characteristics of Abyssal Finescale Motions above Rough Bathymetry

Current-meter data from a two-year mooring within a fracture zone on the western flank of the MidAtlantic Ridge in the South Atlantic Ocean are reported. The mooring, deployed in conjunction with the Brazil Basin Tracer Release Experiment, was placed in the general area where enhanced diapycnal mixing had previously been inferred. The current-meter data characterize the velocity, temperature, shear, and temperature gradient variability as a function of frequency. Energetic velocities and shears were observed at the mooring at a variety of frequencies. In addition to semidiurnal flows, a significant amount of shear variance derived from near-inertial motions, as has been seen in a recent numerical modeling study of tidal-frequency internal wave radiation and wave–wave interaction. At times, a fortnightly modulation of the total superinertial shear variance was indicated in the data, but this signal did not dominate the records. Wave ray tracing indicates that the deeper current meters may have been placed in a shadow zone for locally generated internal tides. At shallower levels, it is suggested that dispersion, wave–wave interaction, and wave breaking effectively obscured the sources of the finescale energy. Average diapycnal diffusivity estimates inferred from a Richardson-number-based parameterization and from observations of temperature inversions at 4648 m were of the same order of magnitude as those derived from turbulent dissipation estimates and from the rate of diapycnal tracer dispersion. The mooring data thus add additional support to the idea that energetic finescale motions above rough bathymetry support enhanced turbulent diapycnal mixing in these regions.
Approaches to the synthesis of endothiopeptides: Synthesis of a thioamide-containing C-terminal bombesin nonapeptide

Abstract Several approaches have been investigated for the synthesis of a bombesin C-terminal nonapeptide analogue AsnGlnTrpAlaVAlGlyHisLeu-ψCSNHMet-NH2. A new activated dithioester 16 has been synthesized. Thioacylation of methionine methyl ester with 16 was always accompanied by racemization, resulting in the formation of diastereomeric mixtures of reaction products.
Excellent normal local domains and extensions of Krull domains

Abstract We consider properties of extensions of Krull domains such as flatness that involve behavior of extensions and contractions of prime ideals. Let ( R , m ) be an excellent normal local domain with field of fractions K, let y be a nonzero element of m and let R ⁎ denote the (y)-adic completion of R. For elements τ 1 , … , τ s of y R ⁎ that are algebraically independent over R, we construct two associated Krull domains: an intersection domain A : = K ( τ 1 , … τ s ) ∩ R ⁎ and its approximation domain B; see Setting 2.2 . If in addition R is countable with dim R ≥ 2 , we prove that there exist elements τ 1 , … , τ s , … as above such that, for each s ∈ N , the extension R [ τ 1 , … , τ s ] ↪ R ⁎ [ 1 / y ] is flat; equivalently, B = A and A is Noetherian. Using this result we establish the existence of a normal Noetherian local domain B such that: B dominates R; B has (y)-adic completion R ⁎ ; and B contains a height-one prime ideal p such that R ⁎ / p R ⁎ is not reduced. Thus B is not a Nagata domain and hence is not excellent. We present several theorems involving the construction. These theorems yield examples where B ⊊ A and A is Noetherian while B is not Noetherian; and other examples where B = A and A is not Noetherian.
Lower bounds for Buchsbaum* complexes

The class of (d-1)-dimensional Buchsbaum* simplicial complexes is studied. It is shown that the rank-selected subcomplexes of a (completely) balanced Buchsbaum* simplicial complex are also Buchsbaum*. Using this result, lower bounds on the h-numbers of balanced Buchsbaum* simplicial complexes are established. In addition, sharp lower bounds on the h-numbers of flag m-Buchsbaum* simplicial complexes are derived, and the case of equality is treated.
Kicking to bigger uprights: Field goal kicking performance influences perceived size

Perception relates not only to the optical information from the environment but also to the perceiver's performance on a given task. We present evidence that the perceived height and width of an American-football field goal post relates to the perceiver's kicking performance. Participants who made more successful kicks perceived the field goal posts to be farther apart and perceived the crossbar to be closer to the ground compared with participants who made fewer kicks. Interestingly, the current results show perceptual effects related to performance only after kicking the football but not before kicking. We also found that the types of performance errors influenced specific aspects of perception. The more kicks that were missed left or right of the target, the narrower the field goal posts looked. The more kicks that were missed short of the target, the taller the field goal crossbar looked. These results demonstrate that performance is a factor in size perception.
Mariner IX Optical Navigation Using Mars Lit Limb

Optical spacecraft navigation data, i.e., the lit limb TV image of Mars, acquired during the approach phase of the Mariner IX spacecraft to Mars, has been successfully demonstrated to augment the radio spacecraft tracking data. Accurate in-flight calibration of the TV instrument and the scan platform was performed by referencing stars and planets. Simulated real-time processing and the detailed postflight analyses of the onboard optical data have shown that planet limb data is an important data source in a far-encounter period for which other types of onboard optical measurements, e.g., natural satellite(s) of the target planet with star background, may not be available.
Internet Politics and State Media Control: Candidate Weblogs in Malaysia:

This article underscores the importance of online research in illuminating the social processes underlying Internet effects on politics. It is an empirical study of the effect of blogs on the 2008 general election in Malaysia. Using the population of electoral candidates in the 2008 general election (N = 471), the author estimates a logistic model predicting the effects of having a blog on winning a Parliamentary seat. The results show that opposition candidates benefit significantly more from having a blog than do non-opposition candidates, as blogging provides opportunities denied to them by Malaysia's state-controlled media. Bloggers are more than seven times as likely to win an election compared to non-bloggers, controlling for incumbency, party membership, and race. In addition to being an alternative avenue of information distribution, blogs' potential for building interpersonal relationships and their role as mobilization tools in media-controlling states are discussed using qualitative examples.
Vibration Suppression of Mistuned Coupled-Blade-Disk Systems Using Piezoelectric Circuitry Network

For bladed-disk assemblies in turbomachinery, the elements are often exposed to aerodynamic loadings, the so-called engine order excitations. It has been reported that such excitations could cause significant structural vibration. The vibration level could become even more excessive when the bladed disk is mistuned, and may cause fatigue damage to the engine components. To effectively suppress vibration in bladed disks, a piezoelectric transducer networking concept has been explored previously by the authors. While promising, the idea was developed based on a simplified bladed-disk model without considering the disk dynamics. To advance the state of the art, this research further extends the investigation with focus on new circuitry designs for a more sophisticated and realistic system model with the consideration of coupled-blade-disk dynamics. A novel multicircuit piezoelectric transducer network is synthesized and analyzed for multiple-harmonic vibration suppression of bladed disks. An optimal network is derived analytically. The performance of the network for bladed disks with random mistuning is examined through Monte Carlo simulation. The effects of variations (mistuning and detuning) in circuit parameters are also studied. A method to improve the system performance and robustness utilizing negative capacitance is discussed. Finally, experiments are carried out to demonstrate the vibration suppression capability of the proposed piezoelectric circuitry network.
A call admission and rate control scheme for multimedia support over IEEE 802.11 wireless LANs

Quality of service (QoS) support for multimedia services in the IEEE 802.11 wireless LAN is an important issue for such WLANs to become a viable wireless access to the Internet. In this paper, we endeavor to propose a practical scheme to achieve this goal without changing the channel access mechanism. To this end, a novel call admission and rate control (CARC) scheme is proposed. The key idea of this scheme is to regulate the arriving traffic of the WLAN such that the network can work at an optimal point. We first s how that the channel busyness ratio is a good indicator of the network status in the sense that it is easy to obtain and can accurately and timely represent channel utilization. Then we propose two algorithms based on the channel busyness ratio. The call admission control algorithm is used to regulate the admission of real-time or streaming traffic and the rate control algorithm to control the transmission rate of best effort traffic. As a result, the real-time or streaming traffic is supported with statistical QoS guarantees and the best effort traffic can fully utilize the residual channel capacity left by the real-time and streaming traffic. In addition, the rate control algorithm itself provides a solution that could be used above the media access mechanism to approach the maximal theoretical channel utilization. A comprehensive simulation study in ns-2 has verified the performance of our proposed CARC scheme, showing that the original 802.11 DCF protocol can statically support strict QoS requirements, such as those required by voice over IP or streaming video, and at the same time, achieve a high channel utilization.
Determination of factors responsible for the declining incidence of colorectal cancer.

INTRODUCTION: After rising for 13 years in the United States, the incidence of colorectal cancer began to fall in 1986 and has continued to drop since then. This report contains an analysis of the pattern of declining colorectal cancer risk by colorectal subsite, race, and gender and a time trend investigation of suspected risk modifiers of colorectal cancer. METHOD: Colorectal cancer incidence data were obtained from the Surveillance, Epidemiology, and End Results Public Use Files from 1973 to 1994. The following exposure variables were assessed, focussing principally on the period 1970 to 1980: dietary fat, fiber, ethanolic beverages, vitamin A, vitamin C, iron, calcium, estrogen, aspirin, energy intake, body mass index, serum cholesterol, body iron stores, cholecystectomy, constipation, cigarette use, physical activity, and colonoscopic polypectomy. Data sources used in these analyses were principally National Health and Nutrition Examination Surveys I, II, and III. RESULTS: After 1985 colorectal cancer incidence declined predominantly in the distal colorectum almost equally in both white males and white females. Some exposures remained unchanged or trended in the wrong direction (dietary fat, calcium, ethanol, energy intake, physical activity, overweight prevalence, and cholecystectomy). Others did not apply equally to both genders (estrogen, aspirin, ethanol, calcium, and cholecystectomy). Others may become significant in the future, such as aspirin, estrogen, or calcium, because their supplementation is now prevalent, but were not in 1970 to 1975. Of all the risk factors or interventions assessed, the one most consistent with the observed pattern of change is increased use of colonoscopic polypectomy. CONCLUSION: The best method to diminish the incidence of colorectal cancer today may be to increase the use of screening colonoscopy and polypectomy.
Young diagrams and N-soliton solutions of the KP equation

We consider N-soliton solutions of the KP equation, An N-soliton solution is a solution u(x, y, t) which has the same set of N line soliton solutions in both asymptotics y → ∞ and y → −∞. The N-soliton solutions include all possible resonant interactions among those line solitons. We then classify those N-soliton solutions by defining a pair of N numbers (n+, n−) with n± = (n±1, ..., n±N), n±j {1, ..., 2N}, which labels N line solitons in the solution. The classification is related to the Schubert decomposition of the Grassmann manifolds Gr(N, 2N), where the solution of the KP equation is defined as a torus orbit. Then the interaction pattern of N-soliton solution can be described by the pair of Young diagrams associated with (n+, n−). We also show that N-soliton solutions of the KdV equation obtained by the constraint ∂u/∂y = 0 cannot have resonant interaction.
RESONANCE TRAPPING IN PROTOPLANETARY DISKS. I. COPLANAR SYSTEMS

Mean-motion resonances (MMRs) are likely to play an important role both during and after the lifetime of a protostellar gas disk. We study the dynamical evolution and stability of planetary systems containing two giant planets on circular orbits near a 2:1 resonance and closer. We find that by having the outer planet migrate inward, the two planets can capture into either the 2:1, 5:3, or 3:2 MMR. We use direct numerical integrations of ~1000 systems in which the planets are initially locked into one of these resonances and allowed to evolve for up to ~107 yr. We find that the final eccentricity distribution in systems which ultimately become unstable gives a good fit to observed exoplanets. Next, we integrate ~500 two-planet systems in which the outer planet is driven to continuously migrate inward, resonantly capturing the inner planet; the systems are evolved until either instability sets in or the planets reach the star. We find that although the 5:3 resonance rapidly becomes unstable under migration, the 2:1 and 3:2 are very stable. Thus the lack of observed exoplanets in resonances closer than 2:1, if it continues to hold up, may be a primordial signature of the planet formation process.
Rotating stall performance and recoverability of a high-speed 10-stage axial flow compressor

Design factors which influence rotating stall recoverability of a high-speed multistage compressor are not yet fully understood. A high-speed, 10-stage compressor component was tested while operating in-stall to investigate parameters that affect the overall recoverability of a multistage compressor. The compressor instrumentation and data acquisition procedures were designed to obtain detailed performance data from the compressor while it entered into a rotating stall condition and while it operated in rotating stall. The compressor was tested at different in-stall operating conditions by varying compressor shaft speed, discharge throttle, and variable geometry settings to determine the effect of each variable on rotating-stall performance and recoverability. Test results suggest that the stall cell may not extend the full length of the compressor but instead can be confined to a portion (here the rear stages) of the compressor. When stages are stacked together, as is the case in a multistage compressor, the stalled performance and subsequent recoverability are greatly affected by how well the stages of the compressor are matched. The results also suggest that high-speed flows in the tenth stage may extend in-stall operation causing low recoverability of the overall test compressor at higher shaft speeds.
Quantum Theory of Gravity. I. The Canonical Theory

Following an historical introduction, the conventional canonical formulation of general relativity theory is presented. The canonical Lagrangian is expressed in terms of the extrinsic and intrinsic curvatures of the hypersurface ${x}^{0}=\mathrm{constant}$, and its relation to the asymptotic field energy in an infinite world is noted. The distinction between finite and infinite worlds is emphasized. In the quantum theory the primary and secondary constraints become conditions on the state vector, and in the case of finite worlds these conditions alone govern the dynamics. A resolution of the factor-ordering problem is proposed, and the consistency of the constraints is demonstrated. A 6-dimensional hyperbolic Riemannian manifold is introduced which takes for its metric the coefficient of the momenta in the Hamiltonian constraint. The geodesic incompletability of this manifold, owing to the existence of a frontier of infinite curvature, is demonstrated. The possibility is explored of relating this manifold to an infinite-dimensional manifold of 3-geometries, and of relating the structure of the latter manifold in turn to the dynamical behavior of space-time. The problem is approached through the WKB approximation and Hamilton-Jacobi theory. Einstein's equations are revealed as geodesic equations in the manifold of 3-geometries, modified by the presence of a "force term." The classical phenomenon of gravitational collapse shows that the force term is not powerful enough to prevent the trajectory of space-time from running into the frontier. The as-yet unresolved problem of determining when the collapse phenomenon represents a real barrier to the quantum-state functional is briefly discussed, and a boundary condition at the barrier is proposed. The state functional of a finite world can depend only on the 3-geometry of the hypersurface ${x}^{0}=\mathrm{constant}$. The label ${x}^{0}$ itself is irrelevant, and "time" must be determined intrinsically. A natural definition for the inner product of two such state functionals is introduced which, however, encounters difficulties with negative probabilities owing to the barrier boundary condition. In order to resolve these difficulties, a simplified model, the quantized Friedmann universe, is studied in detail. In order to obtain nonstatic wave functions which resemble a universe evolving, it is necessary to introduce a clock. In order that the combined wave functions of universe-cum-clock be normalizable, it turns out that the periods of universe and clock must be commensurable. Wave packets exhibiting quasiclassical behavior are constructed, and attention is called to the phenomenological character of "time." The innerproduct definition is rescued from its negative-probability difficulties by making use of the fact that probability flows in a closed finite circuit in configuration space. The article ends with some speculations on the uniqueness of the state functional of the actual universe. It is suggested that a viewpoint due to Everett should be adopted in its interpretation.
The Kato-Ponce Inequality

In this article we revisit the inequalities of Kato and Ponce concerning the L r norm of the Bessel potential J s = (1 − Δ) s/2 (or Riesz potential D s = (− Δ) s/2) of the product of two functions in terms of the product of the L p norm of one function and the L q norm of the Bessel potential J s (resp. Riesz potential D s ) of the other function. Here the indices p, q, and r are related as in Holder's inequality 1/p + 1/q = 1/r and they satisfy 1 ≤ p, q ≤ ∞ and 1/2 ≤ r < ∞ and . Also the estimate is of weak-type when either p or q is equal to 1. In the case r < 1 we indicate via an example that when the inequality fails. Furthermore, we extend these results to the multi-parameter case.
A Kleiman–Bertini theorem for sheaf tensor products

Fix a variety X with a transitive (left) action by an algebraic group G. Let E and F be coherent sheaves on X. We prove that, for elements g in a dense open subset of G, the sheaf Tor_i^X(E, g F) vanishes for all i > 0. When E and F are structure sheaves of smooth subschemes of X in characteristic zero, this follows from the Kleiman-Bertini theorem; our result has no smoothness hypotheses on the supports of E or F, or hypotheses on the characteristic of the ground field.
Features of MCNP6

Abstract MCNP6 can be described as the merger of MCNP5 and MCNPX capabilities, but it is much more than the sum of these two computer codes. MCNP6 is the result of six years of effort by the MCNP5 and MCNPX code development teams. These groups of people, residing in Los Alamos National Laboratory’s X Computational Physics Division, Monte Carlo Codes Group (XCP-3) and Nuclear Engineering and Nonproliferation Division, Radiation Transport Modeling Team (NEN-5) respectively, have combined their code development efforts to produce the next evolution of MCNP. While maintenance and major bug fixes will continue for MCNP5 1.60 and MCNPX 2.7.0 for upcoming years, new code development capabilities only will be developed and released in MCNP6. In fact, the initial release of MCNP6 contains numerous new features not previously found in either code. These new features are summarized in this document. Packaged with MCNP6 is also the new production release of the ENDF/B-VII.1 nuclear data files usable by MCNP. The high quality of the overall merged code, usefulness of these new features, along with the desire in the user community to start using the merged code, have led us to make the first MCNP6 production release: MCNP6 version 1. High confidence in the MCNP6 code is based on its performance with the verification and validation test suites, comparisons to its predecessor codes, our automated nightly software debugger tests, the underlying high quality nuclear and atomic databases, and significant testing by many beta testers.
Long-Horizon Return Regressions With Historical Volatility and Other Long-Memory Variables

The predictability of long-term asset returns increases with the time horizon as estimated in regressions of aggregated-forward returns on aggregated-backward predictive variables. This previously established evidence is consistent with the presence of common slow-moving components that are extracted upon aggregation from returns and predictive variables. Long memory is an appropriate econometric framework for modeling this phenomenon. We apply this framework to explain the results from regressions of returns on risk measures. We introduce suitable econometric methods for construction of confidence intervals and apply them to test the predictability of NYSE/AMEX returns.
Frequent Points for Random Walks in Two Dimensions

For a symmetric random walk in $Z^2$ which does not necessarily have bounded jumps we study those points which are visited an unusually large number of times. We prove the analogue of the Erdos-Taylor conjecture and obtain the asymptotics for the number of visits to the most visited site. We also obtain the asymptotics for the number of points which are visited very frequently by time $n$. Among the tools we use are Harnack inequalities and Green's function estimates for random walks with unbounded jumps; some of these are of independent interest.
The choice of the personal income tax base

Abstract Starting with Vickrey (1945) and Mirrlees (1971), the optimal tax literature has studied the design of a personal income tax. The assumed ideal would be to tax earnings ability. Earnings ability is unobservable for tax purposes, however. Past papers have focused instead on designing a tax on labor income. Existing tax bases, though, depend on a broader range of information about each individual than just labor income. In principle, this supplementary information can help in designing a tax that has more attractive distributional properties, by more closely approximating an ability tax. The objective of this paper is to lay out theoretically and estimate empirically how to make best use of available information about each individual in addition to earnings, in a setting where the first-best tax would be an ability tax. The theory lays out an equity/efficiency trade off when choosing the tax base. In the empirical work, we find the tax base that is best on equity grounds alone. We find that the choice to tax couples based on their joint income, and the inclusion of dividends, interest income, and dependents' deduction in the tax base in roughly their current form can be rationalized simply based on their value in better approximating an ability tax, without any need for supplementary motivations for these provisions. However, the inclusion of mortgage and property tax payments in the list of itemized deductions cannot be defended on these grounds.
Non-perturbative bounds on the Higgs mass in the minimal standard model

Abstract The Higgs mass in the minimal standard model is bounded by triviality and vacuum stability in the range 50–100 GeV to 700–900 GeV . Recent results will be presented in brief and directions for future work will be proposed.
Word-level prosody in Balsas Nahuatl: The origin, development, and acoustic correlates of tone in a stress accent language

Abstract Here we investigate the historical origins and acoustic correlates of a hypothesized tonal development in subdialects of the Nahuatl spoken in the Balsas River valley of central Guerrero state in Mexico. We hypothesize that some subdialects have developed high tone on a syllable preceding a syllable with a breathy-voiced coda [ɦ] (
Optimal sensor placement with terrain-based constraints and signal propagation effects

This paper presents an algorithm for optimal sensor placement that allows one to find the number, types, and locations of sensors satisfying inhomogeneous coverage requirements and minimizing a specified cost function. The cost function can reflect the actual cost of sensors or other disincentives, e.g., the number of sensors, vulnerability, or emplacement costs of the sensors. The sensors are characterized in terms of a probability of detection, which takes into account signature propagation effects, such as geometrical spreading and inhomogeneous attenuation. The proposed approach incorporates many realistic requirements, e.g., existence of high-value objects, obstacles, forbidden emplacement areas, and perimeter protection. For large spatial grids, the strict optimal solution is, in general, difficult to calculate. A fast algorithm for finding a suboptimal but nonetheless highly satisfactory solution is developed. The developed algorithm is compared against a heuristic algorithm that places sensors one-by-one in the most poorly covered spots. Numerical simulations suggest that the algorithm for a suboptimal solution always outperforms the heuristic algorithm. Software for optimal sensor placement is presented and discussed.
Enhancing Bremsstrahlung production from ultraintense laser-solid interactions with front surface structures

We report the results of a combined study of particle-in-cell and Monte Carlo modeling that investigates the production of Bremsstrahlung radiation produced when an ultraintense laser interacts with a tower-structured target. These targets are found to significantly narrow the electron angular distribution as well as produce significantly higher energies. These features combine to create a significant enhancement in directionality and energy of the Bremstrahlung radiation produced by a high-Z converter target. These studies employ short-pulse, high intensity laser pulses, and indicate that novel target design has potential to greatly enhance the yield and narrow the directionality of high energy electrons and γ-rays. We find that the peak γ-ray brightness for this source is 6.0 × 1019 s−1 mm−2 mrad−2 at 10 MeV and 1.4 × 1019 s−1 mm−2 mrad-2 at 100 MeV (0.1% bandwidth).
COMMERCIAL TELEVISION, GLOBALISATION AND THE PUBLIC INTEREST: THE HISTORY OF VOICE OF FIRESTONE

European television is on the brink of being transformed by a new breed of commercial stations which garner revenues from advertisements — not merely taxes, governmental subsidies, and/or legislation which requires viewers to underwrite the programmes they watch. European commercial television, now in its infancy and usually only available to those with cable TV, exhibits all the signs of being an emerging “enfant terrible”. “Annual double‐digit gains in … (TV) advertising in Europe” will continue for the next 20 years, predicts John Eger, a major international media consultant and former senior Vice President of CBS Worldwide Enterprises.
Scope of aminomethylations via Suzuki-Miyaura cross-coupling of organotrifluoroborates.

We previously reported the Suzuki−Miyaura reaction of N,N-dialkylaminomethyltrifluoroborates with aryl bromides. Herein, we report a further investigation of the scope and limitations of this palladium-catalyzed aminomethylation reaction. Aryl chlorides, iodides, and triflates coupled in good to excellent yields to give N,N-dialkylbenzylic amines. The aminomethylation of alkenyl bromides was also examined.
Inverting a supernova: neutrino mixing, temperatures and binding energy

Abstract We show that the temperatures of the emergent non-electron neutrinos and the binding energy released by a galactic Type II supernova are determinable, assuming the Large Mixing Angle (LMA) solution is correct, from observations at the Sudbury Neutrino Observatory (SNO) and at Super-Kamiokande (SK). If the neutrino mass hierarchy is inverted, either a lower or upper bound can be placed on the neutrino mixing angle θ 13 , and the hierarchy can be deduced for adiabatic transitions. For the normal hierarchy, neither can θ 13 be constrained nor can the hierarchy be determined. Our conclusions are qualitatively unchanged for the proposed Hyper-Kamiokande detector.
Fullerene–porphyrin architectures; photosynthetic antenna and reaction center models

Fullerenes and porphyrins are molecular architectures ideally suited for devising integrated, multicomponent model systems to transmit and process solar energy. Implementation of C60 as a 3-dimensional electron acceptor holds great expectations on account of their small reorganization energy in electron transfer reactions and has exerted a noteworthy impact on the improvement of light-induced charge-separation. This article describes how the specific compositions of porphyrin chromophores linked to C60—yielding artificial light harvesting antenna and reaction center mimics—have been elegantly utilized to tune the electronic couplings between donor and acceptor sites and the total reorganization energy. Specifically, the effects that these parameters have on the rate, yield and lifetime of the energetic charge-separated states are considered.
Mediastinal needle biopsy. A 15-year experience with 139 cases.

Background. Radiologically guided needle biopsy and cytologic evaluation provide a reliable method of diagnosis for planning definitive therapy of patients with mediastinal lesions. Materials and Methods. In this retrospective study of one of the largest series from a single institution, 141 consecutive mediastinal needle biopsies from 139 patients were reviewed during a 15-year period. Results. Adequate material was obtained with a diagnosis achieved in 128 cases (92%). Of these, 33 cases (26%) had benign diagnoses ; the remaining 95 (74%) had malignant diagnoses, including 81 carcinomas, 3 sarcomas, 8 lymphoproliferative lesions, 2 malignant germ cell tumors, and 1 malignant thymoma. All benign cases were diagnostically confirmed, and 94 of 95 malignant cases were classified correctly. The only discrepancy that occurred involved a malignant lymphoma diagnosed as a malignant germ cell tumor. Of the 13 inadequate samples, the major category included a nodular sclerosis variant of Hodgkin's disease (4 cases), 1 case of thymoma, 1 case of tuberculous lymphadenitis, and 7 cases for which no follow-up data were available. Conclusion. Needle biopsy is reaffirmed as a reliable and sensitive diagnostic tool for mediastinal lesions, with an overall cytologic diagnostic accuracy of 99% with adequate material. Sclerotic lesions may pose a limitation to this technique and require generous sampling before a more invasive diagnostic procedure is undertaken
Higher-dimensional algebra IV: 2-tangles

Just as knots and links can be algebraically described as certain morphisms in the category of tangles in 3 dimensions, compact surfaces smoothly embedded in R4 can be described as certain 2-morphisms in the 2-category of ‘2-tangles in 4 dimensions’. Using the work of Carter, Rieger and Saito, we prove that this 2-category is the ‘free semistrict braided monoidal 2-category with duals on one unframed self-dual object’. By this universal property, any unframed self-dual object in a braided monoidal 2-category with duals determines an invariant of 2-tangles in 4 dimensions.
Electrocardiographic changes on tilting.

Abstract 1. 1. Electrocardiograms were taken before, during, and after tilting in normal young men in the heat. 2. 2. In control experiments systole was found to be long in relation to the cycle after tilting to the vertical and to be reduced, though not to the initial value, after three minutes. On returning to the horizontal position, systole was short in relation to the cycle and began to approach the resting value after three minutes. 3. 3. These changes were not affected by procedures which altered blood volume and performance by small but definite amounts, that is, bed rest, exposure to cold, hemorrhage, or infusion of serum albumin. 4. 4. Some evidence for the possible role of the vagus in these changes is presented.
Bank Underwriting of Debt Securities: Modern Evidence

This article examines debt securities underwritten by Section 20 subsidiaries of bank holding companies relative to those underwritten by investment houses. Consistent with a net certification effects for banks, bank underwriting of lower credit rated firms to whom the bank lends results in relatively higher prices (lower yields). We find no evidence of conflicts of interest even when an issue is used to repay bank debt. Further, banks bring a relatively larger proportion of small issues to the market. Contrary to the contention that universal banking stunts availability of finance to small firms, bank underwritings appear to benefit small firms. Article published by Oxford University Press on behalf of the Society for Financial Studies in its journal, The Review of Financial Studies.
An outer bound for the memoryless two-user interference channel with general cooperation

The interference channel models a wireless network where several source-destination pairs compete for the same resources. This paper considers a 4-node network, where two nodes are sources and the other two are destinations. All nodes are full-duplex and cooperate to mitigate interference. A sum-rate outer bound is derived, which is shown to unify a number of previously derived outer bounds for special cases of cooperation or feedback. The approach is shown to extend to cooperative interference networks with more than two source-destination pairs and for any partial sum-rate. How the derived bound relates to other channel models including cognitive nodes, i.e., nodes that have non-causal knowledge of the messages of some other node, is also discussed. The bound is evaluated in Gaussian noise.
Distributed Processing and Fiber-Optic Communications in Air Data Measurement

The application of distributed processing, fiber optics, and hardware redundancy to collecting airstream data in the digitally controlled variable-response research aircraft (VRA) at the Flight Research Laboratory of Princeton University is described. Microprocessor-controlled instrumentation packages in each wingtip of the aircraft collect angle-of-attack and sideslip data in digital form; after scaling, filtering, and calibrating the data, they send it to the microprocessor digital flight control system (micro-DFCS) via digital fiber-optic data links. Each wingtip package is independent of the other; therefore, the system has dual hardware redundancy. The fiver-optic link design is presented as well as a description of the calibration and communications software. Translation of the system's dual redundancy into fault tolerance is also covered. Results of preliminary flight tests are included.
Global imbalances and financial stability

Abstract There are two opposing views on global imbalances: The “traditional” view, which regards the imbalances as a threat to global economic and financial stability, and the “new paradigm” view, which considers that they are the natural consequence of economic and financial globalization. In terms of their policy implications, the traditional view focuses on monetary and fiscal policy decisions in the United States that need to be urgently reversed to avoid an abrupt unwinding of the imbalances involving a sell-off of dollar assets, a sharp increase in U.S. interest rates, and a hard landing for the global economy. By contrast, the new paradigm view considers that the imbalances will be resolved smoothly through the normal functioning of markets. This paper argues that an abrupt unwinding of imbalances is highly unlikely and advances a number of arguments in support of the new paradigm view.
Extremal subspaces and their submanifolds

It was proved in the paper [KM1] that the properties of almost all points of $ \mathbb{R}^{n} $ being not very well (multiplicatively) approximable are inherited by nondegenerate in $ \mathbb{R}^{n} $ (read: not contained in a proper affine subspace) smooth submanifolds. In this paper we consider submanifolds which are contained in proper a.ne subspaces, and prove that the aforementioned Diophantine properties pass from a subspace to its nondegenerate submanifold. The proofs are based on a correspondence between multidimensional Diophantine approximation and dynamics of lattices in Euclidean spaces.
Solubility in compressible polymers: Beyond the regular solution theory

Abstract The age-old idea of “like dissolves like” requires a notion of “likeness” that is hard to quantify for polymers. We revisit the concepts of pure component cohesive energy density cP and mutual cohesive energy density c12 so that they can be extended to polymers. We recognize the inherent limitations of c12 due to its very definition, which is based on the assumption of no volume of mixing (true for incompressible systems), one of the assumptions in the random mixing approximation (RMA); no such limitations are present in the identification of cP. We point out that the other severe restriction on c12 is the use of pure components in its definition because of which c12 is not merely controlled by mutual interactions. Another quantity c 12 SRS as a measure of mutual cohesive energy density that does not suffer from the above limitations of c12 is introduced. It reduces to c12 in the RMA limit. We are able to express c 12 SRS in terms of c12 and pure component cP’s. We also revisit the concept of the internal pressure and its relationship with the conventional and the newly defined cohesive energy densities. In order to investigate volume of mixing effects, we introduce two different mixing processes in which volume of mixing remains zero. We then carry out a comprehensive reanalysis of various quantities using a recently developed recursive lattice theory that has been tested earlier and has been found to be more accurate than the conventional regular solution theory such as the Flory–Huggins theory for polymers. In the RMA limit, our recursive theory reduces to the Flory–Huggins theory or its extension for a compressible blend. Thus, it supersedes the Flory–Huggins theory. Consequently, the conclusions based on our theory are more reliable and should prove useful.
Stored Chemical Energy Propulsion System for Underwater Applications

An underwater propulsion system that couples a lithium fueled boiler with a standard Rankine cycle has been developed and demonstrated in an ocean environment. Although the demonstration vehicle was a small diameter axisymmetric body, other configurations have been subjected to study and experimentation. Various fuel-oxidizer combinations have been considered for use in the system, and these are examined along with the necessary supporting technologies for future development efforts. A brief history of the system development is included. It is concluded that the described system has been shown to be a viable candidate for numerous underwater applications.
Gaugino mass nonuniversality and dark matter in supergravity, strings, and D-brane models

The effects of nonuniversality of gaugino masses on dark matter are examined within supersymmetric grand unification, and in string and D-brane models with R parity invariance. In SU(5) unified models nonuniversality in the gaugino sector can be generated via the gauge kinetic energy function which may depend on the 24, 75 and 200 dimensional Higgs representations. We also consider string models which allow for nonuniversality of gaugino masses and D-brane models where nonuniversality arises from embeddings of the standard model gauge group on five-branes and nine-branes. It is found that with gaugino mass nonuniversality the range of the LSP mass can be extended much beyond the range allowed in the universal SUGRA case, up to about 600 GeV even without coannihilation effects in some regions of the parameter space. The effects of coannihilation are not considered and inclusion of these effects may further increase the allowed neutralino mass range. Similarly with the inclusion of gaugino mass nonuniversality, the neutralino-proton $(\ensuremath{\chi}\ensuremath{-}p)$ cross section can increase by as much as a factor of 10 in some regions of the parameter space. An analysis of the uncertainties in the quark density content of the nucleon is given and their effects on the $\ensuremath{\chi}\ensuremath{-}p$ cross section are discussed. The predictions of our analysis including nonuniversality are compared with the current limits from dark matter detectors and implications for future dark matter searches are discussed.
X-Ray Properties of Pre-Main-Sequence Stars in the Orion Nebula Cluster with Known Rotation Periods

We reanalyze all archival Chandra/ACIS observations of the Orion Nebula Cluster (ONC) to study the X-ray properties of a large sample of pre–main-sequence (PMS) stars with optically determined rotation periods. Our goal is to elucidate the origins of X-rays in PMS stars by seeking out connections between the X-rays and the mechanisms most likely driving their production—rotation and accretion. Stars in our sample have LX/Lbol near, but below, the ‘‘saturation’’ value of 10 � 3 . In addition, in this sample X-ray luminosity is significantly correlated with stellar rotation, in the sense of decreasing LX/Lbol with more rapid rotation. These findings suggest that stars with optical rotation periods are in the ‘‘super-saturated’’ regime of the rotation-activity relationship, consistent with their Rossby numbers. However, we also find that stars with optical rotation periods are significantly biased to high LX. This is not the result of magnitude bias in the optical rotation–period sample, but rather of the diminishingly small amplitude of optical variations in stars with low LX. Evidently, there exists in the ONC a population of stars whose rotation periods are unknown and that possess lower average X-ray luminosities than those of stars with known rotation periods. These stars may sample the linear regime of the rotation-activity relationship. Accretion also manifests itself in X-rays, though in a somewhat counterintuitive fashion: while stars with spectroscopic signatures of accretion show harder X-ray spectra than nonaccretors, they show lower X-ray luminosities and no enhancement of X-ray variability. We interpret these findings in terms of a common origin for the X-ray emission observed from both accreting and nonaccreting stars, with the X-rays from accreting stars simply being attenuated by magnetospheric accretion columns. This suggests that X-rays from PMS stars have their origins primarily in chromospheres, not accretion.
Dopaminergic influences on prolactin synthesis and release from rat anterior pituitary cultures

Dopaminergic influences on prolactin release from lactotrophs have been studied using the rat anterior pituitary cell culture. The prolactin inhibiting activity of hypothalamic extracts was examined in relation to dopamine. Dopamine inhibited prolactin secretion from the rat anterior pituitary cell culture in a dose dependent fashion. The median effective dose was 2 x 10 -7 M and the maximal inhibition (70-90 ~o of the control value) was shown by 10 -5 M dopamine. Further increase in dopamine concentration did not result in any further inhibition of prolactin secretion. Dopamine antagonists such as haloperidol and (§ could inhibit the effect of dopamine on prolactin release. A Schild plot from the relationship between dopamine and (+)butaclamol in prolactin release in the anterior pituitary cell culture showed that pAz value of (+)butaclamol is 8.9 with a slope of 1.00. High concentrations of haloperidol or (+) butaclamol (both above 10-SM) caused a marked inhibition in prolactin release initially, followed by some irreversible cytotoxicity on the anterior pituitary cells. The major damage
Housing and Urban Development Indicators: A Good Idea Whose Time Has Returned

This special issue of Real Estate Economics is devoted to “Housing and Urban Development Indicators.” The issue has been underwritten by the United States Department of Housing and Urban Development as a U.S. Contribution to the United Nation's Habitat II Conference, held in Istanbul, Turkey in June 1996. This introduction first briefly explains the role of indicators in urban research. Current research on indicators is then described, including a major international research effort undertaken in over fifty countries with support from numerous academics and other researchers, the United Nations, the World Bank and a number of governments. Finally, the papers in this issue are introduced and placed in context.
Reverse Mortgages and Interest Rate Risk

We develop and apply a valuation model that quantifies the interest rate risk inherent in fixed-rate reverse mortgages. Consistent with intuition, our results show that the interest rate risk of a reverse mortgage is greater than that of either a typical coupon bond or a regular mortgage. Somewhat surprisingly, we find that this difference in interest rate risk is extremely large. In fact, the interest rate risk of a reverse mortgage often is several orders of magnitude greater than the interest rate risk of other fixed-income securities.