cssi/SciSciGPT-SciSciNet huggingface dataset:
Field-theoretic polymer simulations

A method is presented for numerically sampling functional integrals in field theory models of polymer solutions and melts. The approach effectively relaxes the mean-field approximation in self-consistent field theories of equilibrium polymer phases. Viewed from another perspective, the method provides an alternative to conventional particle-based simulations of coarse-grained models of polymers. We demonstrate the technique by applying it to examine fluctuation effects on the order-disorder transition in symmetric diblock copolymer melts. Extensions to more complex polymer blends, copolymers, and solutions are outlined.
Ileal Conduit Urinary Diversion in Patients With Previous History of Abdominal/Pelvic Irradiation

Urinary diversion among patients receiving prior radiation is common. Herein, we present our experience with ileal conduit (IC) diversion in patients with a history of prior abdominal and/or pelvic radiation therapy. We analyzed the charts of 177 patients who underwent IC urinary diversion between 1/1994 and 6/2000, and 36 patients were identified who had previously undergone radiation therapy. Decisions to proceed were based on surgeon preference as determined by intraoperative appearance and viability of the selected bowel segment. Chart review included serum studies, upper tract imaging studies, and complications related to diversion. Durability of diversion was determined by examining the interval between urinary diversion and the need for additional procedures. A total of 30 patients with at least 3 months follow-up were identified. Renal function remained stable in 86% (26/30) with a median follow-up of 21.5 months (range 3–63 months). Hydronephrosis was noted preoperatively in 4 patients (13%) who demonstrated stable upper tracts and serum creatinine in the post-operative period. Three patients (10%) developed unilateral hydronephrosis related to tumor recurrence, with one patient demonstrating a rise in baseline serum creatinine. Hydronephrosis was noted in 5 patients (16%) secondary to development of ureteroenteric stricture. Serum creatinine remained stable in 2 patients without intervention with 2 years follow-up. Intervention for obstruction was necessary in 3 patients at 22, 31, and 61 months following diversion. In one patient, an intraoperative decision to use the colon for urinary diversion was made secondary to appearance of small bowel. Minor complications were noted in 9 patients (30%), while 3 patients (10%) experienced major complications in the immediate post-operative period. Five patients (17%) experienced complications potentially related to the use of ileum for urinary diversion. The use of ileum for urinary diversion among patients with a history of radiation appears technically feasible and a viable treatment alternative. Our data support the use of ileum in the majority of patients as evidence by a low complication rate and a high rate of upper tract preservation. In addition, these data imply that a prior history of abdominal and/or pelvic radiation should not serve as the sole determining factor in the selection of bowel segment utilized during urinary diversion.
The space complexity of pass-efficient algorithms for clustering

We present multiple pass streaming algorithms for a basic clustering problem for massive data sets. If our algorithm is allotted 2l passes, it will produce an approximation with error at most e using O(k3/e2/l) bits of memory, the most critical resource for streaming computation. We demonstrate that this tradeoff between passes and memory allotted is intrinsic to the problem and model of computation by proving lower bounds on the memory requirements of any l pass randomized algorithm that are nearly matched by our upper bounds. To the best of our knowledge, this is the first time nearly matching bounds have been proved for such an exponential tradeoff for randomized computation.In this problem, we are given a set of n points drawn randomly according to a mixture of k uniform distributions and wish to approximate the density function of the mixture. The points are placed in a datastream (possibly in adversarial order), which may only be read sequentially by the algorithm. We argue that this models, among others, the datastream produced by a national census of the incomes of all citizens.
Dynamic task allocation in cooperative robot teams

In this paper, a dynamic task allocation and controller design methodology for cooperative robot teams is presented. Fuzzy-logic-based utility functions are derived to quantify each robot's ability to perform a task. These utility functions are used to allocate tasks in real time through a limited lookahead control methodology partially based on the basic principles of discrete event supervisory control theory. The proposed controller design methodology accommodates flexibility in task assignments, robot coordination, and tolerance to robot failures and repairs. Implementation details of the proposed methodology are demonstrated through a warehouse patrolling case study.
Three-graviton amplitude in Berkovits–Vafa–Witten variables

Abstract We compute the three-graviton tree amplitude in Type IIB superstring theory compactified to six dimensions using the manifestly (6d) supersymmetric Berkovits–Vafa–Witten worldsheet variables. We consider two cases of background geometry: the flat space example R 6 ×K3, and the curved example AdS 3 × S 3 ×K3 with Ramond flux, and compute the correlation functions in the bulk.
The Ithaca interpretation of quantum mechanics

I list several strong requirements for what I would consider a sensible interpretation of quantum mechanics and discuss two simple recent theorems which have important implications for such an interpretation. My talk will not clear everything up; indeed, you may conclude that it has not cleared anything up. But I hope it will provide a different perspective from which to view some old and vexing puzzles (or, if you believe nothing needs to be cleared up, some ancient verities.)
From Generalized Dirac Equations to a Candidate for Dark Energy

We consider extensions of the Dirac equation with mass terms and . The corresponding Hamiltonians are Hermitian and pseudo-Hermitian ( Hermitian), respectively. The fundamental spinor solutions for all generalized Dirac equations are found in the helicity basis and brought into concise analytic form. We postulate that the time-ordered product of field operators should yield the Feynman propagator ( prescription), and we also postulate that the tardyonic as well as tachyonic Dirac equations should have a smooth massless limit. These postulates lead to sum rules that connect the form of the fundamental field anticommutators with the tensor sums of the fundamental plane-wave eigenspinors and the projectors over positive-energy and negative-energy states. In the massless case, the sum rules are fulfilled by two egregiously simple, distinguished functional forms. The first sum rule remains valid in the case of a tardyonic theory and leads to the canonical massive Dirac field. The second sum rule is valid for a tachyonic mass term and leads to a natural suppression of the right-handed helicity states for tachyonic particles and left-handed helicity states for tachyonic spin-1/2 antiparticles. When applied to neutrinos, the theory contains a free tachyonic mass parameter. Tachyons are known to be repulsed by gravity. We discuss a possible role of a tachyonic neutrino as a contribution to the accelerated expansion of the Universe “dark energy.”
Combustion generated noise in gas turbine combustors

Experiments were conducted to determine the noise power and spectra emitted from a gas turbine combustor can exhausting to the atmosphere. Limited hot wire measurements were made of the cold flow turbulence level and spectra within the can. The fuels used were JP-4, acetone and methyl alcohol burning with air at atmospheric pressure. The experimental results show that for a fixed fuel the noise output is dominated by the airflow rate and not the fuel/air ratio. The spectra are dominated by the spectra of the cold flow turbulence spectra which were invariant with airflow rate in the experiments. The effect of fuel type on the noise power output was primarily through the heat of combustion and not the reactivity. A theory of combustion noise based upon the flame radiating to open surroundings is able to reasonably explain the observed results. A thermoacoustic efficiency for noise radiation as high as .00003 was observed in this program for JP-4 fuel. Scaling rules are presented for installed configurations.
Technique for recovering images from tightly confined spaces

An approach is described for the recovery of images from tightly confined spaces by use of multimode fibers, and an analytical demonstration shows that the concept is sound. The proof of concept draws on earlier studies that concentrated on image recovery after two-way and one-way transmissions through a multimode fiber; both types of transmission used four-wave-mixing techniques. The approach described also uses four-wave mixing but utilizes two fibers to capture the image at some intermediate point that is accessible to the fibers but that is visually inaccessible to the casual viewer.
Explicit Optimal Hardness via Gaussian Stability Results

The results of Raghavendra [2008] show that assuming Khot’s Unique Games Conjecture [2002], for every constraint satisfaction problem there exists a generic semidefinite program that achieves the optimal approximation factor. This result is existential as it does not provide an explicit optimal rounding procedure nor does it allow to calculate exactly the Unique Games hardness of the problem.Obtaining an explicit optimal approximation scheme and the corresponding approximation factor is a difficult challenge for each specific approximation problem. Khot et al. [2004] established a general approach for determining the exact approximation factor and the corresponding optimal rounding algorithm for any given constraint satisfaction problem. However, this approach crucially relies on results explicitly proving optimal partitions in the Gaussian space. Until recently, Borell’s result [1985] was the only nontrivial Gaussian partition result known.In this article we derive the first explicit optimal approximation algorithm and the corresponding approximation factor using a new result on Gaussian partitions due to Isaksson and Mossel [2012]. This Gaussian result allows us to determine the exact Unique Games Hardness of MAX-3-EQUAL. In particular, our results show that Zwick’s algorithm for this problem achieves the optimal approximation factor and prove that the approximation achieved by the algorithm is a 0.796 as conjectured by Zwick [1998].We further use the previously known optimal Gaussian partitions results to obtain a new Unique Games Hardness factor for MAX-k-CSP: Using the well-known fact that jointly normal pairwise independent random variables are fully independent, we show that the UGC hardness of Max-k-CSP is ⌈(k+1)/2⌉ 2k−1, improving on results of Austrin and Mossel [2009].
Distributed Storage Codes Reduce Latency in Vehicular Networks

We investigate the benefits of distributed storage using erasure codes for file sharing in vehicular networks through both analysis and realistic trace-based simulations. We show that the key parameter affecting the on-demand file download latency is the ratio of file size to download bandwidth. When this ratio is small so that a file can be communicated in a single encounter, we find that coding techniques offer very little benefit over simple file replication. However, we analytically show that for large ratios, for a memoryless contact model, distributed erasure coding yields a latency benefit of $N/\alpha$ over uncoded replication, where $N$ is the number of vehicles and $\alpha$ the redundancy factor. Effectively, in this regime, coding yields the same performance as replicating all the files at all other vehicles, but using much less storage. We also evaluate the benefits of coded storage using large real vehicle traces of taxis in Beijing and buses in Chicago. These simulations, which include a realistic radio link quality model for a IEEE 802.11p dedicated short range communication (DSRC) radio, validate the observations from the analysis, demonstrating that coded storage dramatically speeds up the download of large files in vehicular networks.
Carbohydrate-derived partners display remarkably high stereoselectivity in aldol coupling reactions

Abstract Aldol condensation between 3-keto and aldehyde sugars have been studied. The enolate 3 reacts with aldehydes preferentially from the β-face to give axial C2 condensation products. However, if the reaction conditions are not controlled properly some C2 epimerization may be observed. With respect to the aldehyde partner, facial selectivity can be predicted on the basis of the preferred, permissible chelation pattern. Thus α/β chelation (which occurs whenever possible) produces Cram products, while α-chelation produces anti-Cram products. For the major (C2-axial) products, the stereochemistry around the newly forged C2C7 bond can be determined by the magnitude of J2,7= 8–10 Hz for the C7-(S) condensation product, and ~5 Hz for the C7-(R) analogue. The C3-carbonyl group of the aldol products can be reduced with DIBAL and LiALH4 to give products bearing equatorial and axial C3-OH groups, respectively. On the other hand, LiBHEt3 gives axial alcohols only. The ease of formation of an isopropylidene ring between the equatorial C3-OH and C7-OH can be used to deduce the C7 orientation. For example, with the C7-(R) isomer 25 (eq), an isopropylidene ring was readily formed whereas for the C7-(S) analogue 28, ring formation was not observed.
A TRACKER SOLUTION TO THE COLD DARK MATTER COSMIC COINCIDENCE PROBLEM

Abstract Recently, we introduced the notion of “tracker fields,” a form of quintessence which has an attractor-like solution. Using this concept, we showed how to construct models in which the ratio of quintessence to matter densities today is independent of initial conditions. Here we apply the same idea to the standard cold dark matter component in cases where it is composed of oscillating fields. Combining these ideas, we can construct a model in which quintessence, cold dark matter, and ordinary matter all contribute comparable amounts to the total energy density today irrespective of initial conditions.
Synchronizing rankings via interactive communication

We consider the problem of exact synchronization of two rankings at remote locations connected by a two-way channel. Such synchronization problems arise when items in the data are distinguishable, as is the case for playlists, tasklists, crowdvotes and recommender systems rankings. Our model accounts for different constraints on the communication throughput of the forward and feedback links, resulting in different anchoring, syndrome and checksum computation strategies. Information editing is assumed of the form of deletions, insertions, block deletions/insertions, translocations and transpositions. The protocols developed under the given model are order-optimal with respect to genie aided lower bounds.
A model for and discussion of multi-interpreter systems

A multi-interpreter system is a system in which programs execute by virtue of being interpreted by other programs, which themselves may either be interpreted (i.e. nested interpreters) or run directly on the host machine. The model reveals the anatomy of interpreters and how these differ from procedures, and exhibits links to protection domains and multiprocessor architectures.
Nourdin–Peccati analysis on Wiener and Wiener–Poisson space for general distributions

Abstract Given a reference random variable, we study the solution of its Stein equation and obtain universal bounds on its first and second derivatives. We then extend the analysis of Nourdin and Peccati by bounding the Fortet–Mourier and Wasserstein distances from more general random variables such as members of the Exponential and Pearson families. Using these results, we obtain non-central limit theorems, generalizing the ideas applied to their analysis of convergence to Normal random variables. We do these in both Wiener space and the more general Wiener–Poisson space. In the former space, we study conditions for convergence under several particular cases and characterize when two random variables have the same distribution. In the latter space we give sufficient conditions for a sequence of multiple (Wiener–Poisson) integrals to converge to a Normal random variable.
Identifying Compact Symmetric Objects in the Southern Sky

We present results of multifrequency polarimetric VLBA observations of 20 compact radio sources. The observations represent the northern and southern extensions of a large survey undertaken to identify compact symmetric objects (CSOs) observed in the northern sky. CSOs are young radio galaxies whose jet axes lie close to the plane of the sky and whose appearance is therefore not dominated by relativistic beaming effects. The small linear sizes of CSOs make them valuable for studies of both the evolution of radio galaxies and testing unified schemes for active galactic nuclei. In this paper we report on observations of 20 new CSO candidates discovered in the northern and southern extremities of the VLBA Calibrator Survey. We identify four new CSOs, and discard 12 core-jet sources. The remaining four sources remain candidates pending further investigation. We present continuum images at 5 and 15 GHz and, where relevant, images of the polarized flux density and spectral index distributions for the eight new CSOs and CSO candidates.
Where were the auditors? Using AAERs in introductory or advanced auditing courses

Abstract I provide instructions for use of a Securities and Exchange Commission (SEC) Accounting and Auditing Enforcement Release (AAER) assignment by instructors in Introductory or Advanced Audit Courses. The assignment gives students an opportunity to use the knowledge they have gained from their auditing and other accounting courses. Students analyze what was done by individuals in a company to cause the SEC to issue an AAER and what the external auditors could have done to prevent the AAER from happening. A secondary feature of the assignment is that students are able to practice their presentation skills by presenting their analysis to their class members and instructor. The assignment can also lead to class discussion on ethics and what ethical dilemmas practicing auditors are faced with.
A technique for speeding up the solution of the Lagrangian dual

We propose techniques for the solution of the LP relaxation and the Lagrangean dual in combinatorial optimization and nonlinear programming problems. Our techniques find the optimal solution value and the optimal dual multipliers of the LP relaxation and the Lagrangean dual in polynomial time using as a subroutine either the Ellipsoid algorithm or the recent algorithm of Vaidya. Moreover, in problems of a certain structure our techniques find not only the optimal solution value, but the solution as well. Our techniques lead to significant improvements in the theoretical running time compared with previously known methods (interior point methods, Ellipsoid algorithm, Vaidya's algorithm). We use our method to the solution of the LP relaxation and the Langrangean dual of several classical combinatorial problems, like the traveling salesman problem, the vehicle routing problem, the Steiner tree problem, thek-connected problem, multicommodity flows, network design problems, network flow problems with side constraints, facility location problems,K-polymatroid intersection, multiple item capacitated lot sizing problem, and stochastic programming. In all these problems our techniques significantly improve the theoretical running time and yield the fastest way to solve them.
Workers as geographical actors

In this paper I first detail some of the geographical concepts that help us make sense of capitalism's spatiality. I then provide several brief vignettes which illustrate how conflicts over how capitalism's geography is made can be central to disputes both between and within groups of workers and capitalists. The paper's purpose is to argue that understanding how social life is geographically structured can add important insights to explaining economic and political praxis.
Reinforcing CPR skills without mannequin practice

We studied the effectiveness of two refresher methods on skills that did not involve mannequin practice. Sixty-seven Seattle subjects trained one year earlier were pretested and randomly assigned to one of two treatments that covered the technique of one-rescuer CPR: reading a three-page review (n = 33); or viewing a 15-minute videotape (n = 34). Subjects were tested on a recording mannequin immediately after the refresher. Pretest scores were low on almost all skills. After treatment, both groups demonstrated significant improvement ( P P
Optimal Incorporation, Structure of Debt Contracts, and Limited-Recourse Project Financing

Abstract We analyze the interrelationships among the corporate organization structure, the capital structure, and the ownership structure of a firm with multiple projects, when incumbent management derives control benefits. The choices made by firm management are: (1) Whether to set up projects as a joint firm or as separate firms (spin-off), (2) the amount of debt financing to use, (3) the structure of the debt contract (e.g., straight debt on the joint firm, limited-recourse project financing, or spin-off with straight debt), and (4) the fraction of equity to hold in each firm (ownership structure). Differences in managerial ability across projects, benefits of control, and the probability of loss of control through a takeover or through bankruptcy are driving factors in this model. We relate the project characteristics to the optimality of spin-offs and limited-recourse project financing arrangements, and derive implications for the allocation of debt and the ownership structure across projects. Journal of Economic Literature Classification Numbers: G32, G34, D21.
Virtual real source

Estimation of the seismic source signature is an important problem in reflection seismology, especially in seismic imaging problems. Existing methods of source signature estimation (statistical methods and well-log-based methods) suffer from several drawbacks. Here, I introduce a method of extracting the source signature based on the theory of seismic interferometry, also known as the virtual source method. The only requirement for this method is to have a receiver location lie at the shot position whose source signature we want to estimate (not necessarily a zero-offset receiver). Through modeling examples, I show that the Virtual Real Source method produces accurate source signatures even for complicated subsurface and source signatures. Source signature of each shot can be extracted reliably if they all have similar amplitude spectra even though their phase spectra might be completely different. This method of source signature estimation not only gives accurate traveltimes and amplitudes of reflection events, but also has the potential to solve other issues, such as finding source radiation patterns, measuring intrinsic attenuation, and estimating statics.
ON D3-BRANE DYNAMICS AT STRONG WARPING

We study the dynamics of a D3 brane in generic IIB warped compactifications, using the Hamiltonian formulation discussed in arXiv:0805.3700. Taking into account of both closed and open string fluctuations, we derive the warped Kahler potential governing the motion of a probe D3 brane. By including the backreaction of D3, we also comment on how the problem of defining a holomorphic gauge coupling on wrapped D7 branes in warped background can be resolved.
Coarse-grained modeling of the interface between water and heterogeneous surfaces

Using coarse-grained models we investigate the behavior of water adjacent to an extended hydrophobic surface peppered with various fractions of hydrophilic patches of different sizes. We study the spatial dependence of the mean interface height, the solvent density fluctuations related to drying the patchy substrate, and the spatial dependence of interfacial fluctuations. We find that adding small uniform attractive interactions between the substrate and solvent cause the mean position of the interface to be very close to the substrate. Nevertheless, the interfacial fluctuations are large and spatially heterogeneous in response to the underlying patchy substrate. We discuss the implications of these findings for the assembly of heterogeneous surfaces.
Determination of gold, silver and cobalt in aluminum by flameless atomic absorption spectroscopy

Flameless atomic absorption spectroscopy has been successfully applied to the analysis of trace levels of gold, silver and cobalt in milligram quantities of aluminum. The two-line method of background correction was used with good, but not total, success. The reproducibility of the measurements was excellent, and the results compared very well with the expected values.
Globular cluster origin of X-ray bursters

Abstract X-ray bursters and galactic bulge x-ray sources, or the most luminous x-ray sources in the galaxy, are reasonably well constrained in their basic nature but not in their origin. We have suggested they may all have been produced by tidal capture in high density cores of globular clusters, which have now largely been disrupted by tidal stripping and shocking in the galactic plane. General arguments are presented for cluster disruption by the possible ring of giant molecular clouds in the Galaxy. Tests of the cluster disruption hypothesis are in progress and preliminary results are summarized here. The G-K star “companions” previously noted for at least 4 bursters have spectra (in the two cases observed) consistent with metal rich cluster giants. Several possibilities are discussed, including the formation of hierarchical triples in the dissolving cluster or in the galactic plane.
Regionalization of disturbance-induced nitrogen leakage from mid-Appalachian forests using a linear systems model

The ‘leakage’ of nitrate-nitrogen (nitrate-N) to surface waters is a common (but not universal) response of forest ecosystems to both human-induced and natural disturbances. There are several reported examples of the transient leakage of nitrate-N to surface waters from eastern US forests that have sustained outbreaks of defoliating insects, such as the introduced gypsy moth (Lymantria dispar) larva. Previous research has suggested that annual nitrate-N leakage from disturbed forests can be modelled using an empirically derived unit nitrogen export response function (UNERF) model. The model represents annual nitrate-N export as a linear deterministic process in both space and time and is analogous to a unit hydrograph. The goal of the present study was to verify and apply a regionalized, lithology-based UNERF model that references the geographic distribution of bedrock class and the timing and extent of gypsy moth defoliation of forests in the non-glaciated highlands of the Chesapeake Bay watershed. Despite an inability to verify the model for most individual watersheds within the study area, the model was able to reproduce the statistical distribution of annual nitrate-N export to streams that comprised our target population. During water year 1991 (the year following peak defoliation) the model results indicated that regional annual nitrate-N export had transiently increased by nearly 1500% from a baseline rate of about 0·1 kg ha−1 to a peak value approaching 1·5 kg ha−1. We thus conclude that natural vegetation disturbance is an important mechanism by which dissolved nitrogen is leaked from forested lands to small streams, rivers, and Chesapeake Bay. The present study also illustrates how simple, empirically derived linear systems approaches like the UNERF model can be successfully applied to problems where regionalization is a primary goal. Copyright © 2004 John Wiley & Sons, Ltd.
The uses of supramolecular chemistry in synthetic methodology development: examples of anion and neutral molecular recognition

The principles of supramolecular chemistry have successfully permeated through a broad range of organic chemistry subdisciplines. One subdiscipline that is not routinely associated with supramolecular chemistry is that of organic synthetic methodology. Though sometimes indiscernible, non-bonded and bonding supramolecular interactions play a large role in chemical reactions and catalysis. Many synthetic methods hinge on the creation of anionic charge, albeit just partial, at some step during this process, and hence are prime targets for molecular recognition interactions. Examples are artificial enzymes, biomimetic catalysis, organocatalysis, and many of the catalysts that are derived from a combinatorial screen. Further, supramolecular chemistry is playing an increasingly large role in high-throughput analytical techniques. This tutorial review ties together supramolecular approaches to methodology creation, combinatorial screening, and analytical protocols. The goal is to show, and further predict, that supramolecular chemistry will continually increase its impact in organic synthetic methodology development.
Particle trapping during passage through a high-order nonlinear resonance

Abstract A theory of particle trapping and transport during a single passage through a high-order nonlinear resonance is developed. The main result is an expression for the trapping efficiency as a function of two scaling variables which are related to the resonance excitation width, the nonlinear detuning and the speed of passage through the resonance. The question of what phase-space region trapped particles are drawn from and the question of adiabaticity are discussed. The theory is then verified with a computer simulation for crossing a fifth order resonance.
Olefin epoxidation by manganese (IV) porphyrins: evidence for two reaction pathways

The reaction of chloro(5,10,15,20-tetramesitylporphinato)manganese(III) with m-chloroperoxybenzoic acid in CH2Cl2 containing methanolic (NMe4)OH at 0 °C yields the Mn(IV) complex (Ia).
Global sawtooth oscillations of the magnetosphere

Global sawtooth oscillations are periodic changes in the morphology of the magnetosphere wherein the magnetic field in the inner regions strongly stretches and then rapidly crashes or dipolarizes. The period of the oscillation is about three hours, with the crash phase lasting 5–15 min. At geosynchronous orbit, a sawtooth oscillation of the magnetosphere appears as a periodic decline and rapid recovery of the energetic particle fluxes at all local times; such an oscillation is shown in Figure 1. Global sawtooth oscillations occur during some, but not all, geomagnetic storms. Owing to the extremely large amplitudes of the sawtooth oscillations, nearly all measurements taken in the magnetosphere show signatures of the sawtooth oscillations.
Pediatric ventricular assist device use as a bridge to transplantation does not affect long-term quality of life

Objective The present study sought to determine the long-term quality of life (QOL) of children who required long-term ventricular assist device (VAD) support as a bridge to transplantation (BTT) compared with children who underwent heart transplantation without VAD support. Currently, 20% of children undergoing heart transplantation have required a VAD as a BTT. Few data have been published assessing how children requiring a VAD as a BTT will fair in terms of their long-term QOL. Methods The present study used a cross-sectional design, using the Core and Cardiac modules of the Pediatric Quality of Life Inventory survey. In a secondary analysis, the factors associated with worse QOL outcomes among the VAD patients were also investigated. Results At follow-up (median, 4.2 years), between the 21 children who required a VAD as a BTT and 42 who went straight to transplantation, no significant differences were found in the QOL as measured using the Psychosocial Health Summary Score, Physical Health Summary Score, or Total Score in the survey's Core Module, nor were any differences found in the outcomes assessed using the survey's Cardiac Module. Of the patients who required a VAD, only the presence of a neurologic complication was associated with worse QOL, which was demonstrated by decreased Physical Health Summary and Cardiac Communication scores. Conclusions Over the long term, surviving children who required a long-term VAD as a BTT experience a similar QOL as those who went straight to transplantation.
Supersymmetric noncommutative QED and Lorentz violation

We consider Lorentz-violating operators induced at the loop level in softly-broken supersymmetric noncommutative QED. Dangerous operators forbidden in the supersymmetric limit are generated via finite corrections, with the scale of supersymmetry breaking serving as a gauge-invariant regulator. We compare the most dangerous loop effects to those obtained in noncommutative theories truncated by a momentum-space cutoff, and find significantly improved bounds.
The Arecibo Legacy Fast ALFA Survey. IV. Strategies for Signal Identification and Survey Catalog Reliability

We present a signal-extraction utility written for the purposes of the Arecibo Legacy Fast ALFA survey. This survey, when completed, will have covered ~7000 deg2 of the high Galactic latitude sky and should detect over 20,000 extragalactic objects. It is the most sensitive blind H I survey to date. The large size of the survey justifies in itself the need for an automated way of identifying signals in the data set. The matched-filtering signal extractor proposed is based on convolutions in the Fourier domain of templates of varying widths with each spectrum. The chosen templates are built from a simple combination of Hermite functions to mimic the shape of typical Galactic H I profiles of varying widths. The main advantages of this matched-filtering approach are a sensitivity to the total flux of the signals (and not only to peak flux), robustness against instabilities, and short computing times. The details of the algorithm are given here, as well as results of simulations that assess the reliability and completeness of the process.
CORE-COLLAPSE SUPERNOVAE AND HOST GALAXY STELLAR POPULATIONS

We have used images and spectra of the Sloan Digital Sky Survey to examine the host galaxies of 519 nearby supernovae (SN). The colors at the sites of the explosions, as well as chemical abundances, and specific star formation rates (SFRs) of the host galaxies provide circumstantial evidence on the origin of each SN type. We examine separately SN II, SN IIn, SN IIb, SN Ib, SN Ic, and SN Ic with broad lines (SN Ic-BL). For host galaxies that have multiple spectroscopic fibers, we select the fiber with host radial offset most similar to that of the SN. Type Ic SN explode at small host offsets, and their hosts have exceptionally strongly star-forming, metal-rich, and dusty stellar populations near their centers. The SN Ic-BL and SN IIb explode in exceptionally blue locations, and, in our sample, we find that the host spectra for SN Ic-BL show lower average oxygen abundances than those for SN Ic. SN IIb host fiber spectra are also more metal-poor than those for SN Ib, although a significant difference exists for only one of two strong-line diagnostics. SN Ic-BL host galaxy emission lines show strong central specific SFRs. In contrast, we find no strong evidence for different environments for SN IIn compared to the sites of SN II. Because our SN sample is constructed from a variety of sources, there is always a risk that sampling methods can produce misleading results. We have separated the SN discovered by targeted surveys from those discovered by galaxy-impartial searches to examine these questions and show that our results do not depend sensitively on the discovery technique.
Applications of digital computers to problems in the study of vehicular traffic

The study of vehicular traffic on a scientific basis is still in its infancy. This is due to the enormity of the job. Currently, research in this area is carried on along two distinct lines. First, there is the approach which attempts to study traffic conditions in the small and gradually builds up to larger systems. This is an approach which may accomplish the desired goals, but from all current indications success in this area is distant.
Weakness of Will and the Free-Rider Problem

The study of intrapersonal economic relations, or economics, is still at the programmatic stage. There is no generally accepted paradigm, or even as well-defined set of problems that constitute it as a subdiscipline within economics. Some questions are, however, emerging as foci of interest for a small but increasing number of writers, not just in economics, but also in psychology and philosophy. The writings of Thomas Schelling on self-management, of George Ainslie on self-control, and of Derik Parfit on personal identity testify to this convergence.
The Lobatamides, Novel Cytotoxic Macrolides from Southwestern Pacific Tunicates†

Novel macrolides, lobatamides A-F (1-6), have been isolated from shallow water Australian collections of Aplidium lobatum, from a deep water collection of Aplidium sp., and from an unidentified Philippine ascidian. Full details of the isolation and structure elucidation of 1-6 are provided herein, along with results and analyses of the testing of lobatamides A-D (1-4) in the NCI human tumor 60 cell-line screen. The lobatamides share a common core structure with the recently described salicylihalamides, which were isolated from a Haliclona sp. sponge. COMPARE analyses of the mean-graph differential cytotoxicity profiles of the lobatamides and the salicylihalamides showed high correlations with each other but not with members of the NCI's standard agents database. These compounds, therefore, appear to comprise a new mechanistic class, meriting further antitumor investigations.
Direct Least-Squares Formulation of a Stiffness Adjustment Method

A direct least-squares formulation of the stiffness matrix adjustment method known as the KMA method (Kabe, A. M., Stiffness Matrix Adjustment Using Mode Data, AIAA Journal, Vol. 23, No. 9, 1985, pp. 1431-1436) is presented. The KMA method belongs to a class of procedures that refine dynamic models using test-measured modes and structural connectivity. Viewed as a constrained minimization problem, most of these methods have applied Lagrange multiplier techniques in their development. It is shown that these two approaches result in linear systems of equations that are algebraically equivalent and therefore have identical solutions. By virtue of this equivalence, the direct least-squares formulation of the KMA method is shown to be equivalent to its original Lagrange multiplier formulation. The direct least-squares versions of other model refinement methods that preserve structural connectivity are also discussed. In this respect, this approach provides a rigorous framework for unifying these optimal update procedures and indicates how their solutions should compare. Numerical results are presented that illustrate the equivalence between the two formulations and also the conditions under which the various methods yield identical solutions. The results also indicate that because of improved numerical conditioning, the direct least-squares approach yields more accurate computational solutions and generally requires less computer storage than methods that were developed using Lagrange multipliers.
Acute effects of changing plasma osmolality and colloid oncotic pressure on the formation of brain edema after cryogenic injury

The cerebral effects of alterations in plasma osmolality (Osm) and colloid oncotic pressure (COP) were examined in normocarbic, normothermic, pentobarbital-anesthetized rabbits that had been subjected to cryogenic brain injury. Monitored variables in all animals included mean arterial, right atrial, and intracranial pressures (MAP, CVP, and ICP), electroencephalographic (EEG) recordings, and cerebral blood flow (CBF). When surgical preparation was complete, a left parietal lesion was produced with liquid nitrogen. Group 1 (control, n = 8) animals subsequently received only maintenance fluids [lactated Ringer's solution (LR)]. One hour after injury, 3 other groups of animals underwent 45 minutes of plasmapheresis, carried out by arterial phlebotomy (packed red cells returned), with separated plasma being replaced by one of three fluids given in amounts sufficient to maintain MAP and CVP at baseline values. The three fluids were 1) 6% hetastarch in hypo-osmotic LR [Group 2 (Hypo-Osm), n = 6; COP = 21 mm Hg, Osm = 130 mOsm/kg]; 2) iso-osmotic LR [Group 3 (Hypo-COP), n = 8; COP = 0; Osm = 305]; and 3) 6% hetastarch in iso-osmotic LR [Group 4 (Iso-Osm/COP), n = 8; COP = 21, Osm = 310]. The animals were killed by exsanguination 25 minutes after completion of plasmapheresis. The brain was removed, the hemispheres separated, weighed, and sliced, and the specific gravities (SpGr) of the regional tissue determined. There were no differences in MAP, CVP, regional CBF, or EEG activity among the groups.(ABSTRACT TRUNCATED AT 250 WORDS)
An efficient synthesis of sulfamides

Abstract Here we report an efficient synthesis of sulfamides. 3,5-Lutidine was found to be an optimal solvent and catalyst for the reaction. The method was developed during our efforts to synthesize a series of novel FKBP-12 inhibitors in which the known ketoamide linker was replaced with sulfamide.
Assembly Configurations of Single-Loop Mechanisms With Pin Joints and Sliding Joints

This paper examines the problem of enumerating the assembly configurations (ACs), also called circuits, of planar mechanisms which can be described as a single loop. A method is given which allows the user to find and distinguish the ACs of such a mechanism, by determining if each pair of adjacent links can line up. If each pair can line up, then the mechanism has one AC; otherwise, it has two ACs. It is shown that a single-loop mechanism can have no more than two ACS. The method is demonstrated with two examples.
New Aspects of Carrier Multiplication in Semiconductor Nanocrystals

One consequence of strong spatial confinement of electronic wave functions in semiconductor nanocrystals (NCs) is a significant enhancement in carrier−carrier Coulomb interactions. This effect leads to a number of novel physical phenomena including ultrafast decay of multiple electron−hole pairs (multiexcitons) by Auger recombination and high-efficiency generation of mutiexcitons by single photons via carrier multiplication (CM). Significant recent interest in multiexciton phenomena in NCs has been stimulated by studies of NC lasing, as well as potential applications of CM in solar-energy conversion. The focus of this Account is on CM. In this process, the kinetic energy of a “hot” electron (or a “hot” hole) does not dissipate as heat but is, instead, transferred via the Coulomb interaction to the valence-band electron, exciting it across the energy gap. Because of restrictions imposed by energy and translational-momentum conservation, as well as rapid energy loss due to phonon emission, CM is inefficient...
Gendered Space in Renaissance Florence: Theorizing Public and Private in the “Rag Trade”

(2005). Gendered Space in Renaissance Florence: Theorizing Public and Private in the “Rag Trade”. Fashion Theory: Vol. 9, No. 2, pp. 125-145.
From Morse-Smale to all knots and links

We analyse the topological (knot-theoretic) features of a certain codimension-one bifurcation of a partially hyperbolic fixed point in a flow on originally described by Shil'nikov. By modifying how the invariant manifolds wrap around themselves, or `pleat', we may apply the theory of templates, or branched two-manifolds, to capture the topology of the flow. This analysis yields a class of flows which bifurcate from a Morse-Smale flow to a Smale flow containing periodic orbits of all knot and link types.
Spatial and temporal patterns of remotely-sensed and field-measured rainfall in southern California

Abstract Quantification of spatial and temporal patterns of rainfall is an important step toward developing regional hydrological models. However, traditionally used rain gauge data are sparse and do not always provide adequate spatial representation of rainfall. In this study, we evaluated the daily 1-degree resolution remotely-sensed atmospheric precipitation data provided by Global Precipitation Climatology Project (GPCP) as an alternative to rain gauge-measured data. We analyzed data from the watersheds of southern California during the period of 1996–2003, focusing on the comparison of patterns of spatial, seasonal, and interannual rainfall dynamics. We used Empirical Orthogonal Functions to discern the patterns of precipitation and atmospheric circulation at different time scales, from synoptic to interannual. The correlation between the daily rain gauge-measured and remotely-sensed precipitation was poor and the resulting patterns of remotely-sensed precipitation are different than the temporal patterns of precipitation accumulated by rain gauges. These differences likely result from the fact that the precipitable water concentration measured by satellites is not always highly correlated to rainfall reaching the earth surface. Differences in the spatial resolution and coverage of the two methods and the differential influence of orographic effects and wind patterns on each also contribute to low correlations. We conclude that daily remotely-sensed precipitation produced at GPCP is not currently appropriate for use in assessing fine-scale hydrological processes in arid zones like southern California, and would not be a recommended surrogate for event-based hydrologic modeling. At the same time, the interannual variabilities of remotely-sensed and gauge-measured precipitation were highly correlated and the regional patterns of gauge-measured and remotely-sensed precipitation variability were similar; though the total precipitation estimated from satellite data was substantially lower than the gauge-measured data. Therefore, remotely-sensed precipitation data may be appropriate for use in long-term regional hydrologic or climate modeling focused on trends and patterns of rainfall in southern California. Both data sets showed that precipitation generally decreases from the northern to the southern watersheds. At interannual time-scale, the rainfall is related to the ENSO cycle. At synoptic time-scales, the rainfall patterns in southern California result from atmospheric moisture transport from the south–southwest.
A fault tolerant, area efficient architecture for Shor's factoring algorithm

We optimize the area and latency of Shor's factoring while simultaneously improving fault tolerance through: (1) balancing the use of ancilla generators, (2) aggressive optimization of error correction, and (3) tuning the core adder circuits. Our custom CAD flow produces detailed layouts of the physical components and utilizes simulation to analyze circuits in terms of area, latency, and success probability. We introduce a metric, called ADCR, which is the probabilistic equivalent of the classic Area-Delay product. Our error correction optimization can reduce ADCR by order of magnitude or more. Contrary to conventional wisdom, we show that the area of an optimized quantum circuit is not dominated exclusively by errorcorrection. Further, our adder evaluation shows that quantum carry-lookahead adders (QCLA) beat ripple-carry adders in ADCR, despite being larger and more complex. We conclude with what we believe is one of most accurate estimates of the area and latency required for 1024-bit Shor's factorization: 7659 mm2 for the smallest circuit and 6 x 108 seconds for the fastest circuit.
Understanding welfare stigma: Taxpayer resentment and statistical discrimination

Abstract Welfare stigma is widely regarded to be of central importance in understanding the impact of welfare programs in their goal of alleviating poverty. It affects both the decision to take up benefits and the well-being of those who actually do. This paper develops alternative models of the determinants of welfare stigma. We identify two views: a statistical discrimination approach and a taxpayer resentment view. We discuss how each may be formalized and derive their implications. We then examine what they imply about the relationship between stigma and program design.