cssi/SciSciGPT-SciSciNet huggingface dataset:
In Vivo Phase Variation of Escherichia Coli Type 1 Fimbrial Genes in Women With Urinary Tract Infection

Type 1 fimbriae, expressed by most Escherichia coli strains, are thought to attach to human uroepithelium as an initial step in the pathogenesis of urinary tract infections (UTI). Numerous reports using both in vitro and murine models support this role for type 1 fimbriae in colonization. Unfortunately, only a limited number of studies have directly examined the expression of fimbriae in vivo. To determine whether type 1 fimbrial genes are transcribed during an acute UTI, we employed a modification of an established method. The orientation (ON or OFF) of the invertible promoter element, which drives transcription of type 1 fimbrial genes, was determined by PCR amplification using primers that flank the invertible element, followed by SnaBI digestion. The orientation of the type 1 fimbrial switch was determined under three experimental conditions. First, E. coli strains from different clinical sources (acute pyelonephritis patients, cystitis patients, and fecal controls) were tested under different in vitro culture conditions (agar versus broth; aerated versus static). The genes in the more-virulent strains (those causing acute pyelonephritis) demonstrated a resistance, in aerated broth, to switching from OFF to ON, while those in fecal strains readily switched from OFF to ON. Second, bladder and kidney tissue from CBA mice transurethrally inoculated with E. coli CFT073 (an established murine model of ascending UTI) was assayed. The switches directly amplified from infected bladder and kidney tissues were estimated to be 33 and 39% ON, respectively, by using a standard curve. Finally, bacteria present in urine samples collected from women with cystitis were tested for type 1 fimbria switch orientation. For all 11 cases, an average of only 4% of the switches in the bacteria in the urine were ON. In 7 of the 11 cases, we found that all of the visible type 1 fimbrial switches were in the OFF position (upper limit of detection of assay, 98% OFF). Strains recovered from these urine samples, however, were shown after culture in vitro to be capable of switching the fimbrial gene to the ON position and expressing mannose-sensitive hemagglutinin. The results from experimental infections and cases of cystitis in women suggest that type 1 fimbrial genes are transcribed both in the bladder and in the kidney. However, those bacteria found in the urine and not attached to the uroepithelium are not transcriptionally active for type 1 fimbrial genes.
Three-dimensional pure permanent magnet undulator design theory

Expressions for fields due to a point charge in 3D and due to a line charge in 2D are compared. Extensions to dipoles are made with emphasis on the relationship between dipole orientation and field component magnitudes. Differences between the effects on fields of dipole rotations in 2D and in 3D are highlighted and formulas for maximizing individual field components are given. A final macrogeometry extension is made and a closed-form expression is developed to calculate the field due to an arbitrary 3D configuration of permanent magnet (PM) blocks. The field optimization theory is applied to the design of the ALS elliptically polarizing undulator (EPU). Utilizing 3D field enhancement, peak on-axis field in practical designs can be increased typically by 5% to 40% or more over their 2D counterparts. The theory is generally applicable to any pure (i.e., no soft magnetic material) PM design.
Residual migration velocity analysis in the plane-wave domain

Over the last few years, migration-velocity analysis methods have been developed for 2-D and 3-D models by extending the assumptions and approximations used for rms velocity models. Computational requirements for these analyses have increased dramatically because top-down layer-stripping migration is needed to derive interval velocities directly instead of using rms velocities and then converting into interval velocities. We establish exact equations for 1-D and 2-D residual velocity analysis in the depth-plane-wave domain and use these in an iterative and interactive migration velocity analysis program. The new method updates interval velocities directly in a top-down residual-difference correction for all layers after prestack depth migration instead of top-down layer-stripping migration followed by residual analysis. This makes the new method a suitable tool for migration velocity analysis, especially for 3-D surveys. We test the method on synthetic and field data. The field data results show that a reasonable velocity model is obtained and most common image gathers are correctly imaged using no more than four iterations.
Merging the potential of microbial genetics with biological and chemical diversity: an even brighter future for marine natural product drug discovery

Marine invertebrates and a growing number of marine bacteria are the sources of novel, bioactive secondary metabolites. Structurally, many of these compounds appear to be biosynthesized by polyketide synthases (PKS) and/or nonribosomal peptide synthetases (NRPS) that have also been found in terrestrial microbes. This review highlights scientific advances from 1999-2003 in the emerging field of molecular genetics of polyketide and nonribosomal peptide natural products isolated from marine organisms. The implications of this research towards the development of marine secondary metabolites as a sustainable source of new drugs are discussed.
Unique Identification of Lee-Wick Gauge Bosons at Linear Colliders ∗†

Grinstein, O'Connell and Wise have recently presented an extension of the Standard Model (SM), based on the ideas of Lee and Wick (LW), which demonstrates an interesting way to remove the quadratically divergent contributions to the Higgs mass induced by radiative corrections. This model predicts the existence of negative-norm copies of the usual SM fields at the TeV scale with ghost-like propagators and negative decay widths, but with otherwise SM-like couplings. In earlier work, it was demonstrated that the LW states in the gauge boson sector of these models, though easy to observe, cannot be uniquely identified as such at the LHC. In this paper, we address the issue of whether or not this problem can be resolved at an e{sup +}e{sup -} collider with a suitable center of mass energy range. We find that measurements of the cross section and the left-right polarization asymmetry associated with Bhabha scattering can lead to a unique identification of the neutral electroweak gauge bosons of the Lee-Wick type.
A weak Galerkin finite element method with polynomial reduction

The weak Galerkin (WG) is a novel numerical method based on variational principles for weak functions and their weak partial derivatives defined as distributions. In the implementation, the weak partial derivatives and the weak functions are approximated by polynomials with various degrees of freedom. The accuracy and the computational complexity of the corresponding WG scheme is significantly impacted by the selection of such polynomials. This paper presents an optimal combination for the polynomial spaces that minimize the number of unknowns in the numerical scheme without compromising the accuracy of the numerical approximation. For illustrative purpose, the authors use the second order elliptic equation to demonstrate the basic ideas of polynomial reduction. Consequently, a new weak Galerkin finite element method is proposed and analyzed. Error estimates of optimal order are established for the corresponding WG approximations in both a discrete H 1 norm and the standard L 2 norm. In addition, the paper presents some numerical results to demonstrate the power of the WG method in dealing with finite element partitions with arbitrary polygons in 2D or polyhedra in 3D. The numerical examples include various finite element partitions such as triangular mesh, quadrilateral mesh, honeycomb mesh in 2D and mesh with deformed cubes in 3D.
Bounded gaps between primes in number fields and function fields

The Hardy--Littlewood prime $k$-tuples conjecture has long been thought to be completely unapproachable with current methods. While this sadly remains true, startling breakthroughs of Zhang, Maynard, and Tao have nevertheless made significant progress toward this problem. In this work, we extend the Maynard-Tao method to both number fields and the function field $\mathbb{F}_q(t)$.
Inferring the Underlying Structure of Information Cascades

In social networks, information and influence diffuse among users as cascades. While the importance of studying cascades has been recognized in various applications, it is difficult to observe the complete structure of cascades in practice. In this paper we study the cascade inference problem following the independent cascade model, and provide a full treatment from complexity to algorithms: (a) we propose the idea of consistent trees as the inferred structures for cascades, these trees connect source nodes and observed nodes with paths satisfying the constraints from the observed temporal information. (b) We introduce metrics to measure the likelihood of consistent trees as inferred cascades, as well as several optimization problems for finding them. (c) We show that the decision problems for consistent trees are in general NP-complete, and that the optimization problems are hard to approximate. (d) We provide approximation algorithms with performance guarantees on the quality of the inferred cascades, as well as heuristics. We experimentally verify the efficiency and effectiveness of our inference algorithms, using real and synthetic data.
Information technology support for communities of practice: How public defenders learn about winning and losing in court

The aim of this article is to examine the role of information technologies (IT) in supporting practice and professional identity formation, both major axes for communities of practice. The article uses an ethnographic case study to understand how public defenders learn to improve their court performance. The concept of “communities of practice” helps to illuminate how the attorneys in a public defender's office share knowledge in order to practice effectively in court. This article presents findings that a community of practice serves as effective scaffolding to support professional development; this is especially true for the practice component. Further, this case study indicates that information technologies, such as listservs, are not very effective social integrators for professionals who work at different sites. In particular, today's IT forums are most effective when used for sharing technical information about work, and least effective for sharing important cultural meanings about how professionals should approach their work and develop professional identities. This research advances our understanding of the complexity of organizing communities of practice to support professional groups of colleagues and of organizing IT-enabled support for various activities of the community. © 2007 Wiley Periodicals, Inc.
Design and analysis of an MST-based topology control algorithm

In this paper, we present a minimum spanning tree (MST)-based algorithm, called local minimum spanning tree (LMST), for topology control in wireless multihop networks. In this algorithm, each node builds its LMST independently and only keeps on-tree nodes that are one-hop away as its neighbors in the final topology. We analytically prove several important properties of LMST: 1) the topology derived under LMST preserves the network connectivity; 2) the node degree of any node in the resulting topology is bounded by 6; and 3) the topology can be transformed into one with bidirectional links (without impairing the network connectivity) after removal of all unidirectional links. Simulation results show that LMST can increase the network capacity as well as reduce the energy consumption.
Nature versus Nurture in Shallow Convection

Abstract Tracers are used in a large-eddy simulation of shallow convection to show that stochastic entrainment (and not cloud-base properties) determines the fate of convecting parcels. The tracers are used to diagnose the correlations between a parcel’s state above the cloud base and both the parcel’s state at the cloud base and its entrainment history. The correlation with the cloud-base state goes to zero a few hundred meters above the cloud base. On the other hand, correlations between a parcel’s state and its net entrainment are large. Evidence is found that the entrainment events may be described as a stochastic Poisson process. A parcel model is constructed with stochastic entrainment that is able to replicate the mean and standard deviation of cloud properties. Turning off cloud-base variability has little effect on the results, which suggests that stochastic mass-flux models may be initialized with a single set of properties. The success of the stochastic parcel model suggests that it holds promi...
Estimation via Markov chain Monte Carlo

Markov chain Monte Carlo (MCMC) is a powerful means for generating random samples that can be used in computing statistical estimates and marginal and conditional probabilities. MCMC methods rely on dependent (Markov) sequences having a limiting distribution corresponding to a distribution of interest. This article is a survey of popular implementations of MCMC, focusing particularly on the two most popular specific implementations of MCMC: Metropolis-Hastings (M-H) and Gibbs sampling. Our aim is to provide the reader with some of the central motivation and the rudiments needed for a straightforward application.
Mechanical Alloying of Titanium‐Base Alloys

Application of mechanical alloying to titanium-base alloys is a recent development. A wide range of terminal phases and those based on titanium aluminides (both Ti3Al and TiAl) have been examined and it has been shown that synthesis of metallic phases can be achieved by mechanical alloying. The phases so synthesized include solid solutions, intermediate crystalline phases, amorphous phases, and nanostructured materials. It has also been shown that the resistance to coarsening of both the grains and the dispersoids in mechanically alloyed Ti3Al based alloys is much higher than in rapidly solidified alloys. The review concludes with some thoughts on future developments in this exciting area.
Microwave promoted oxazole synthesis: Cyclocondensation cascade of oximes and acyl chlorides

Abstract Microwave irradiation promotes the rapid O,N-acylation–cyclodehydration cascade reaction of oximes and acid chlorides to give oxazoles.
Khovanov homology of the $2$-cable detects the unknot

Inspired by recent work of Grigsby and Werhli, we use the deep geometric content of Ozsvath and Szabo's Floer homology theory to provide a short proof that the Khovanov homology of the 2-cable detects the unknot. A corollary is that Khovanov's categorification of the 2-colored Jones polynomial detects the unknot.
Archaeology of overshoot and collapse

AbstractThe literature on sustainability and the human future emphasizes the belief that population and/or mass consumption caused resource degradation and collapse in earlier societies. Archaeological literature proposing overshoot and collapse appears in current debates over resource conservation versus continued economic growth. The prominence of this debate, with its national and international dimensions, makes it important to assess whether there is evidence in the archaeological literature for overshoot and collapse brought on by Malthusian overpopulation and/or mass consumption.
Harmonics in Gaussian multiplicative and additive noise: Cramer-Rao bounds

The concern here is retrieval of single and multiple tone harmonics observed in white Gaussian multiplicative and additive noise. Computable Cramer-Rao bound (CRB) expressions are derived on the frequency and phase estimates as well as on the sample mean or variance of the multiplicative noise processes. The zero- and nonzero-mean multiplicative noise cases are addressed separately and are shown to yield distinct CRBs on the frequency and phase estimates. Tight lower and upper bounds on the CRBs themselves are developed, which, relative to the CRBs, are intuitively more appealing and easier to implement. Well-established formulas on the achievable accuracy for estimates of constant amplitude harmonics turn put to be special cases of our results. Numerical studies support our claims. >
Minimax Rates of Estimation for High-Dimensional Linear Regression Over $\ell_q$ -Balls

Consider the high-dimensional linear regression model y = X β* + w, where y ∈ \BBRn is an observation vector, X ∈ \BBRn × d is a design matrix with d >; n, β* ∈ \BBRd is an unknown regression vector, and w ~ N(0, σ2I) is additive Gaussian noise. This paper studies the minimax rates of convergence for estimating β* in either l2-loss and l2-prediction loss, assuming that β* belongs to an lq -ball \BBBq(Rq) for some q ∈ [0,1]. It is shown that under suitable regularity conditions on the design matrix X, the minimax optimal rate in l2-loss and l2-prediction loss scales as Θ(Rq ([(logd)/(n)])1-q/2). The analysis in this paper reveals that conditions on the design matrix X enter into the rates for l2-error and l2-prediction error in complementary ways in the upper and lower bounds. Our proofs of the lower bounds are information theoretic in nature, based on Fano's inequality and results on the metric entropy of the balls \BBBq(Rq), whereas our proofs of the upper bounds are constructive, involving direct analysis of least squares over lq-balls. For the special case q=0, corresponding to models with an exact sparsity constraint, our results show that although computationally efficient l1-based methods can achieve the minimax rates up to constant factors, they require slightly stronger assumptions on the design matrix X than optimal algorithms involving least-squares over the l0-ball.
Multivariable flight control for an attack helicopter

This paper discusses advanced flight control for the Apache YAH-64 helicopter. The control laws have been flight tested and were extensively evaluated with fixed-base piloted simulation as part of the Advanced Rotorcraft Technology Integration Flight Experiment. The control system employs as sensors normal and lateral acclerometers and three body rate gyros; for control, it uses collective, tail rotor, and lateral and longitudinal cyclic controls. The control laws were developed to provide decoupling, gust attenuation, desensitization, and stability augmentation in the face of aircraft modeling uncertainty. A multivariable proportional-plus-integral element is the basic ingredient of the control. Various analyses are presented, including frequency and time responses and stability robustness properties using singular-value and structured singular-value techniques. Responses of the controlled helicopter to pilot and gust inputs are examined using time histories.
Holography in superspace

The AdS/CFT correspondence identifies the coordinates of the conformal boundary of anti-de Sitter space with the coordinates of the conformal field theory. We generalize this identification to theories formulated in superspace. As an application of our results, we study a class of Wilson loops in Script N = 4 super-Yang-Mills theory. A gauge theory computation shows that the expectation values of these loops are invariant under a local κ-symmetry, except at intersections. We identify this with the κ-invariance of the associated string worldsheets in the corresponding bulk superspace.
New analysis of the proper motions of the Magellanic Clouds using HST /WFPC2

In HST Cycles 11 and 13 we obtained two epochs of ACS/HRC data for fields in the Magellanic Clouds centered on background quasars. We used these data to determine the proper motions of the LMC and SMC to better than 5% and 15% respectively. The results had a number of unexpected implications for the Milky Way-LMC-SMC system. The implied three-dimensional velocities were larger than previously believed and close to the escape velocity in a standard 10^12 solar mass Milky Way dark halo, implying that the Clouds may be on their first passage. Also, the relative velocity between the LMC and SMC was larger than expected, leaving open the possibility that the Clouds may not be bound to each other. To further verify and refine our results we requested an additional epoch of data in Cycle 16 which is being executed with WFPC2/PC due to the failure of ACS. We present the results of an ongoing analysis of these WFPC2 data which indicate good consistency with the two-epoch results.
The Frontiers of Intellectual Property: Expanded Protection versus New Models of Open Science

The growing salience of intellectual property (IP) rights has reconfigured U.S. science, shifting it from the formerly separate realms of university and commercial science to an increasingly interconnected field of public and proprietary science. We assess both the magnitude and consequences of these developments, first describing the primary tools of IP and the changing nature of their influence on science, and then examining the effects of IP on the roles, rules, and relations of the scientific enterprise. We also consider the emergence of new models of scientific practice that blend both public and private. We debate whether current changes represent a transition or transformation in the relations between science and property. Finally, we argue that just as the public and private spheres of science may be converging, so must future scholarship if we are to answer harder questions about the appropriate balance between traditional logics of open science and the more recent regimes of proprietary science.
An Enumerative Geometry for Magic and Magilatin Labellings

A magic labelling of a set system is a labelling of its points by distinct positive integers so that every set of the system has the same sum, the magic sum. Examples are magic squares (the sets are the rows, columns, and diagonals) and semimagic squares (the same, but without the diagonals). A magilatin labelling is like a magic labelling but the values need be distinct only within each set. We show that the number of n n magic or magilatin labellings is a quasipoly- nomial function of the magic sum, and also of an upper bound on the entries in the square. Our results differ from previous ones because we require that the entries in the square all be different from each other, and because we derive our results not by ad hoc reasoning but from a general theory of counting lattice points in rational inside-out polytopes. We also generalize from set systems to rational linear forms.
Participation in the Conservation Reserve Program and Off-Farm Work: Implications for Farm and Farm Household Productivity

Using a national survey of U.S farm households, we investigate the interrelationship between participation in the Conservation Reserve Program (CRP) and the decision to work off the farm. We go on examine the effects of these two decisions on farm and farm household efficiency and productivity by estimating stochastic frontier productions for farm output and multiple output-orientated distance functions that consider income from agricultural sales, the CRP and off-farm work as outputs of the farm household. We control for the effects of self selection in estimating both the frontier production and distance functions. It appears that operators' decisions to work off the farm have led to significant improvements in household resource allocation between farm and other productive activities by farm households -- leading to high technical efficiency for both farm and farm household activities. In contract, participation in the CRP alone leads to the reduction of the technical efficiency and productivity on farm as well as on combined household activities.
Diagnosis and initial management of cerebellar infarction

Summary Cerebellar infarction is an important cause of stroke that often presents with common and non-specific symptoms such as dizziness, nausea and vomiting, unsteady gait, and headache. Accurate diagnosis frequently relies on careful attention to patients' coordination, gait, and eye movements—components of the neurological physical examination that are sometimes omitted or abridged if cerebellar stroke is not specifically being considered. The differential diagnosis is broad, and includes many common and benign causes. Furthermore, early-stage posterior fossa ischaemia is rarely seen with brain CT—the most commonly available initial imaging test that is used for stroke. Insufficient examination and imaging can result in misdiagnosis. However, early correct diagnosis is crucial to help prevent treatable but potentially fatal complications, such as brainstem compression and obstructive hydrocephalus. The identification and treatment of the underlying vascular lesions at an early stage can also prevent subsequent occurrences of stroke and improve patients' outcomes. Here, we review the clinical presentation of cerebellar infarction, from diagnosis and misdiagnosis to patients' monitoring, treatment, and potential complications.
Miscibility of Polyolefin Blends

Phase separation in polymers is important for many technical applications but is difficult to predict theoretically. Recently, extensive experimental studies on the miscibility of polyolefins revealed that these systems display a wider variety of mixing behavior than their chemical similarity suggests. In order to predict phase diagrams of polyolefin blends from pure component properties, we have developed a method in which small scale simulations of local interactions are combined with an analytical model for the thermodynamics, the Born-Green-Yvon lattice model. In this work, we present results for a variety of polyolefin blends and show that the new approach yields qualitatively correct results for phase separation in these blends, including the effects of varying pressure and molar mass of the components on phase separation temperatures.
Profound defects in β-cell function in screen-detected type 2 diabetes are not improved with glucose-lowering treatment in the Early Diabetes Intervention Program (EDIP).

Background Few studies have measured the ability of interventions to affect declining β-cell function in screen-detected type 2 diabetes. The Early Diabetes Intervention Programme (ClinicalTrials.gov NCT01470937) was a randomized study based on the hypothesis that improving postprandial glucose excursions with acarbose would slow the progression of fasting hyperglycaemia in screen-detected type 2 diabetes. In the Early Diabetes Intervention Programme, the effect of acarbose plus lifestyle advice on progression of fasting hyperglycaemia over a 5-year period was not greater than that of placebo. However, there was an early glucose-lowering effect of the trial. The objective of the current secondary analysis was to describe β-cell function changes in response to glucose lowering. Methods Participants were overweight adult subjects with screen-detected type 2 diabetes. β-cell function was measured using hyperglycaemic clamps and oral glucose tolerance testing. The primary outcome was the change in β-cell function from baseline to year 1, the time point where the maximal glucose-lowering effect was seen. Results At baseline, participants exhibited markedly impaired first-phase insulin response. Despite significant reductions in weight, fasting plasma glucose (PG) and 2-h PG, there was no clinically significant improvement in the first-phase insulin response. Late-phase insulin responses declined despite beneficial glycaemic effects of interventions. Conclusions Insulin secretion is already severely impaired in early, screen-detected type 2 diabetes. Effective glucose-lowering intervention with acarbose was not sufficient to improve insulin secretion or halt the decline of β-cell function. Copyright © 2014 John Wiley & Sons, Ltd.
Degrees of freedom of wireless X networks

We study the degrees of freedom characterization of wireless X networks, i.e. networks of M distributed single antenna transmitters and N distributed single antenna receivers where every transmitter has an independent message to every receiver. We provide an outerbound on the capacity region of X networks within o(log(SNR)). If the channel co-efficients are time-varying/frequency selective, we show that the total number of degrees of freedom is equal to MN/M+N-1 using a coding scheme based on the idea of interference alignment.
Building efficient fully collusion-resilient traitor tracing and revocation schemes

In [8,9] Boneh et al. presented the first fully collusion-resistant traitor tracing and trace & revoke schemes. These schemes are based on composite order bilinear groups and their security depends on the hardness of the subgroup decision assumption.In this paper we present new, efficient trace & revoke schemes which are based on prime order bilinear groups, and whose security depend on the hardness of the Decisional Linear Assumption or the External Diffie-Hellman (XDH) assumption. This allows our schemes to be flexible and thus much more efficient than existing schemes in terms a variety of parameters including ciphertext size, encryption time, and decryption time.For example, if encryption time was the major parameter of concern, then for the same level of practical security as [8] our scheme encrypts 6 times faster. Decryption is 10 times faster. The ciphertext size in our scheme is 50% less when compared to [8].We provide the first implementations of efficient fully collusion-resilient traitor tracing and trace & revoke schemes. The ideas used in this paper can be used to make other cryptographic schemes based on composite order bilinear groups efficient as well
Sweeping algebraic curves for singular solutions

Many problems give rise to polynomial systems. These systems often have several parameters and we are interested to study how the solutions vary when we change the values for the parameters. Using predictor-corrector methods we track the solution paths. A point along a solution path is critical when the Jacobian matrix is rank deficient. The simplest case of quadratic turning points is well understood, but these methods no longer work for general types of singularities. In order not to miss any singular solutions along a path we propose to monitor the determinant of the Jacobian matrix. We examine the operation range of deflation and relate the effectiveness of deflation to the winding number. Computational experiments on systems coming from different application fields are presented.
Exploring Meat and Poultry Recall Data for Policy Lessons

Four measures are introduced to evaluate the likelihood of meat and poultry recalls and how firms and FSIS manage such events. These measures include the proportion of product retrieved (recovery rate), time to complete a case, the ratio of recovery rate and completion, and the hazard rate. This research aims to advance our knowledge and understanding of food safety programs by presenting statistical indicators which benchmark the food system. The results from OLS, Negative Binomial, and Cox regression models suggest that limited conclusions can be reached in terms of overall performance and factors that explain the timeliness of recalls. Evidence suggests that smaller plants perform as well as large plants in their recall actions. Also, when the firm discovers the problem recalls are more timely and therefore more effective.
Algorithms for Coloring Quadtrees

We describe simple linear time algorithms for coloring the squares of balanced and unbalanced quadtrees so that no two adjacent squares are given the same color. If squares sharing sides are defined as adjacent, we color balanced quadtrees with three colors, and unbalanced quadtrees with four colors; these results are both tight, as some quadtrees require this many colors. If squares sharing corners are defined as adjacent, we color balanced or unbalanced quadtrees with six colors; for some quadtrees, at least five colors are required.
New Bounds for Restricted Isometry Constants

This paper discusses new bounds for restricted isometry constants in compressed sensing. Let Φ be an n × p real matrix and A; be a positive integer with k ≤ n. One of the main results of this paper shows that if the restricted isometry constant δk of Φ satisfies δk <; 0.307 then k-sparse signals are guaranteed to be recovered exactly via l1 minimization when no noise is present and k-sparse signals can be estimated stably in the noisy case. It is also shown that the bound cannot be substantially improved. An explicit example is constructed in which δk = k-1/2k-1 <; 0.5, but it is impossible to recover certain k-sparse signals.
Spatial transportation networks with transfer costs: asymptotic optimality of hub-and-spoke models

Consider networks on n vertices at average density 1 per unit area. We seek a network that minimizes total length subject to some constraint on journey times, averaged over source-destination pairs. Suppose journey times depend on both route-length and number of hops. Then for the constraint corresponding to an average of 3 hops, the length of the optimal network scales as n13/10. Alternatively, constraining the average number of hops to be 2 forces the network length to grow slightly faster than order n3/2. Finally, if we require the network length to be O(n) then the mean number of hops grows as order log log n. Each result is an upper bound in the worst case (of vertex positions), and a lower bound under randomness or equidistribution assumptions. The upper bounds arise in simple hub and spoke models, which are therefore optimal in an order of magnitude sense.
High density interconnect at 10µm pitch with mechanically keyed Cu/Sn-Cu and Cu-Cu bonding for 3-D integration

The results of bonding and stress testing of Cu/Sn-Cu bonded dice and Cu-Cu thermocompression bonded dice at 10µm and 15µm pitch in large area arrays are shown. The interconnect bonding process pressure and temperature required for the formation of low resistance (<100 mΩ), high yielding (99.99% individual bond yield), and reliable interconnects is described. In the case of Cu/Sn-Cu, use of a mechanical key was found to improve yield. A run of 23 consecutive bond pairs was made with mechanical key, resulting in 92% aggregate channel yield at 10µm pitch in area arrays containing 325,632 individual bonds per die to achieve an interconnect density of 106 / cm2. SEM cross sections of Cu/Sn-Cu and Cu-Cu bonded samples and EDS analysis of Cu/Sn intermetallic compounds both before and after stress testing are presented. The effects of thermal cycling on electrical yield and resistance are presented for Cu/Sn-Cu with underfill. Comparison of the electrical and shear test performance of Cu/Sn-Cu and Cu-Cu is made.
Generic vs. person specific active appearance models

Active Appearance Models (AAMs) are generative parametric models that have been successfully used in the past to model faces. Anecdotal evidence, however, suggests that the performance of an AAM built to model the variation in appearance of a single person across pose, illumination, and expression (a Person Specific AAM) is substantially better than the performance of an AAM built to model the variation in appearance of many faces, including unseen subjects not in the training set (a Generic AAM). In this paper, we present an empirical evaluation that shows that Person Specific AAMs are, as expected, both easier to build and more robust to fit than Generic AAMs. Moreover, we show that: (1) building a generic shape model is far easier than building a generic appearance model, and (2) the shape component is the main cause of the reduced fitting robustness of Generic AAMs. We then proceed to describe two refinements to Generic AAMs to improve their performance: (1) a refitting procedure to improve the quality of the ground-truth data used to build the AAM and (2) a new fitting algorithm. For both refinements we demonstrate dramatically improved fitting performance. Finally, we evaluate the effect of these improvements on a combined model construction and fitting task.
Portfolio Choice and Mental Health

Close to 30% of the US population experiences at least one mental or substance abuse disorder each year. Given the prevalence of mental health issues, this paper analyzes the role of mental health and cognitive functioning in household portfolio choice decisions. Generally, we find that households affected by mental health issues decrease investments in risky instruments. Various men- tal health issues can reduce the probability of holding risky assets by up to 19%. Moreover, single women diagnosed with psychological disorders increase investments in safe assets. We also find that cognitive functioning issues are associated with an increase in financial assets devoted to retirement accounts.
Tertiary aminourea-catalyzed enantioselective iodolactonization.

Binding the anion: A highly enantioselective iodolactonization of 5-hexenoic acids has been achieved using a tertiary aminourea-catalyst. The use of catalytic iodine in this process is critical to enhancing both the reactivity and enantioselectivity of the stoichiometric I+source.The mechanism is proposed to involve binding of an iodonium imidate intermediate by the H-bond donor catalyst.
Inverse Scattering on the Half-Line Revisited

The inverse scattering problem on the half-line has been studied in the literature in detail. V. Marchenko presented the solution to this problem. In this paper, the invertibility of the steps of the inversion procedure is discussed and a new set of necessary and sufficient conditions on the scattering data is given for the scattering data to be generated by a potential q e L 1,1 . Our proof is new and in contrast with Marchenko's proof does not use equations on the negative half-line.
Steady-state errors in discrete-time control systems

Abstract We address discrete-time control systems containing a memoryless nonlinear element and characterize the error response to certain inputs when the circle condition for stability is met.
Types and effects for asymmetric cryptographic protocols

We present the first type and effect system for proving authenticity properties of security protocols based on asymmetric cryptography. The most significant new features of our type system are: (1) a separation of public types (for data possibly sent to the opponent) from tainted types (for data possibly received from the opponent) via a subtype relation; (2) trust effects, to guarantee that tainted data does not, in fact, originate from the opponent; and (3) challenge/response types to support a variety of idioms used to guarantee message freshness. We illustrate the applicability of our system via protocol examples. This material is based upon work supported by the National Science Foundation under Grant No. 0208549.
Synthesis of the Multisubstituted Halogenated Olefins via Cross-Coupling of Dihaloalkenes with Alkylzinc Bromides

The 1-fluoro-1-haloalkenes undergo Pd-catalyzed Negishi cross-couplings with primary alkylzinc bromides to give multisubstituted fluoroalkenes. The alkylation was trans-selective giving pure Z-fluoroalkenes in most cases. The highest yields were obtained with Pd2(dba)3 and PdCl2(dppb) catalysts but the best stereochemical outcome was obtained with less reactive Pd(PPh3)4. The tertiary alkylzincs also produced desired fluoroalkenes in high yields. Coupling of β,β-dichlorostyrene with organozinc reagent resulted in the formation of monocoupled product.
Boundary Effect on Particle Motion in the Head Disk Interface

Simulation of particle motion in the Head Disk Interface (HDI) aids in the understanding of the contamination process on a slider, which is critical for achieving higher areal data densities in hard disk drives. In this paper, the boundary effect—the presence of the slider and the disk—on particle motion in the HDI is investigated. A correction factor to account for this effect is incorporated into the drag force formula for particles in a flow. A contamination criterion is provided to determine when a particle will contaminate a slider. The contamination profile on a specific air bearing surface is obtained, which compares well with experiments.
Oral basal temperatures in abortion and ectopic pregnancy.

Abstract Progestin and estrogen therapy in abortion continues as a controversial issue. Laboratory studies have failed to establish a deficiency of these hormones in the human being as an important etiological factor in the spontaneous termination of early pregnancy. Clinical investigations have accumulated a wide divergenece of opinions as to the value of replacement therapy. Since recent observations have disclosed that the thermal regulating mechanism of the body is directly influenced by progesterone and estrogen, a clinical study of the oral basal temperature curve of patients with threatened and inevitable abortion as well as ectopic pregnancy forms the basis of this study. My study of the oral basal temperature curves of 425 women during normal pregnancy is presented in a previous report. 1 In the event of pregnancy, the postovulatory temperature rise continues during the first trimester. The corpus luteum regresses at the end of the third month of pregnancy and it is at this time that the basal temperature elevation shows a gradual fall, in most cases, so that the estrogen (preovulatory) level is attained by the fourth or fifth month. Since the elevation of basal temperature due to progesterone is present only during the first trimester of pregnancy, this affords an excellent indicator of any significant metabolic changes occurring in threatened and inevitable abortion.
High-Dimensional Multivariate Time Series With Additional Structure

ABSTRACTHigh-dimensional multivariate time series are challenging due to the dependent and high-dimensional nature of the data, but in many applications there is additional structure that can be exploited to reduce computing time along with statistical error. We consider high-dimensional vector autoregressive processes with spatial structure, a simple and common form of additional structure. We propose novel high-dimensional methods that take advantage of such structure without making model assumptions about how distance affects dependence. We provide nonasymptotic bounds on the statistical error of parameter estimators in high-dimensional settings and show that the proposed approach reduces the statistical error. An application to air pollution in the USA demonstrates that the estimation approach reduces both computing time and prediction error and gives rise to results that are meaningful from a scientific point of view, in contrast to high-dimensional methods that ignore spatial structure. In practice,...
Adding real-time capabilities to a SML compiler

There has been much recent interest in adopting functional and reactive programming for use in real-time system design. Moving toward a more declarative methodology for developing real-time systems purports to improve the fidelity of software. To study the benefits of functional and reactive programming for real-time systems, real-time aware functional compilers and language runtimes are required. In this paper we examine the necessary changes to a modern Standard ML compiler, MLton, to provide basic support for real-time execution. We detail our current progress in modifying MLton with a threading model that supports priorities, a chunked object model to support real-time garbage collection, and low level modification to execute on top of a real-time operating system. We present preliminary numbers and our work in progress prototype, which is able to boot ML programs compiled with MLton on x86 machines.
Fossil Fuel Subsidy and Pricing Policies Recent Developing Country Experience

The steep decline in the world oil price in the last quarter of 2014 slashed fuel price subsidies. Several governments responded by announcing that they would remove subsidies for one or more fuels and move to market-based pricing with full cost recovery. Other governments took advantage of low world prices to increase taxes and other charges on fuels. However, the decision to move to cost recovery and market prices, ending budgetary support, has not been implemented consistently across countries. Policy announcements have varied in the way they were communicated and the level of detail provided. When petroleum product prices bounced back during the first half of 2015, some "reforming" governments failed to raise prices correspondingly. Recent experience suggests that regular and frequent price adjustments, however small - as in Jordan and Morocco - help the government and consumers to get accustomed to fluctuations in world fuel prices and exchange rates. By contrast, freezing prices, even for a few months - for socioeconomic considerations or because the needed adjustments are small enough to be absorbed - increases the risk of reversion to ad hoc pricing and price subsidies. The more formally the decision to move to market-based pricing is communicated, the more public new price announcements, and the higher the frequency of price changes, the more likely the implementation of the announced pricing policy reform will be sustained.
Large-scale multipartite entanglement in the quantum optical frequency comb of a depleted-pump optical parametric oscillator

We show theoretically that multipartite entanglement is generated on a massive scale in the spectrum, or optical frequency comb, of a single optical parametric oscillator (OPO) emitting well above threshold. In this system, the quantum dynamics of the strongly depleted pump field are responsible for the onset of the entanglement by correlating the two-mode squeezed, bipartite-entangled pairs of OPO signal fields. (Such pairs are independent of one another in the undepleted, classical pump approximation.) We verify the multipartite nature of the entanglement by evaluating the van Loock-Furusawa criterion for a particular set of entanglement witnesses deduced from physical considerations.