cssi/SciSciGPT-SciSciNet huggingface dataset:
On the observer-based structure of covariance controllers

Abstract The problem of finding the set of all stabilizing full-order controllers is equivalent to a problem of finding all matrices which can be assigned to the closed-loop system as a state covariance. The necessary and sufficient conditions for a given matrix to be assignable as a covariance are given, and all controllers (of plant order) which assign a specific covariance are parametrized explicitly. The structure of covariance controllers is shown for the first time to be observer-based (state estimator plus estimated-state feedback). The ‘central’ state estimator of the covariance controller is shown to be the Kalman filter. Unlike the traditional estimator-based controller, the separation principle does not hold, but one can design a controller by assigning the estimation error covariance and the plant state covariance simultaneously.
Robust spectral inference for Joint Stochastic Matrix Factorization

Spectral inference provides fast algorithms and provable optimality for latent topic analysis. But for real data these algorithms require additional ad-hoc heuristics, and even then often produce unusable results. We explain this poor performance by casting the problem of topic inference in the framework of Joint Stochastic Matrix Factorization (JSMF) and showing that previous methods violate the theoretical conditions necessary for a good solution to exist. We then propose a novel rectification method that learns high quality topics and their interactions even on small, noisy data. This method achieves results comparable to probabilistic techniques in several domains while maintaining scalability and provable optimality.
EFFECTS OF DIURETICS ON CALCIUM METABOLISM

In addition to their known effects on sodium metabolism diuretic agents also exert profound effects on calcium metabolism. A substantial body of data bearing on this subject, some of which conflicting, has now accumulated in the literature. The purpose of this review is to discuss the results of studies on the effects of low-ceiling and high-ceiling diuretics on serum calcium, urinary calcium, bone calcium and the transport of calcium in the gut. The review will include studies in normal humans and experimental animals, and during various pathological states.
Dynamic Learning of Patient Response Types: An Application to Treating Chronic Diseases

Currently available medication for treating many chronic diseases is often effective only for a subgroup of patients, and biomarkers accurately assessing whether an individual belongs to this subgroup typically do not exist. In such settings, physicians learn about the effectiveness of a drug primarily through experimentation—i.e., by initiating treatment and monitoring the patient’s response. Precise guidelines for discontinuing treatment are often lacking or left entirely to the physician’s discretion. We introduce a framework for developing adaptive, personalized treatments for such chronic diseases. Our model is based on a continuous-time, multi-armed bandit setting where drug effectiveness is assessed by aggregating information from several channels: by continuously monitoring the state of the patient, but also by (not) observing the occurrence of particular infrequent health events, such as relapses or disease flare-ups. Recognizing that the timing and severity of such events provide critical inform...
Hybrid Noncoherent Network Coding

We describe a novel extension of subspace codes for noncoherent networks, suitable for use when the network is viewed as a communication system that introduces both dimension and symbol errors. We show that when symbol erasures occur in a significantly large number of different basis vectors transmitted through the network and when the min-cut of the network is much smaller than the length of the transmitted codewords, the new family of codes outperforms their subspace code counterparts. For the proposed coding scheme, termed hybrid network coding, we derive two upper bounds on the size of the codes. These bounds represent a variation of the Singleton and of the sphere-packing bound. We show that a simple concatenated scheme that consists of subspace codes and Reed-Solomon codes is asymptotically optimal with respect to the Singleton bound. Finally, we describe two efficient decoding algorithms for concatenated subspace codes that in certain cases have smaller complexity than their subspace decoder counterparts.
Differences in employment outcomes for college town stayers and leavers

New college graduates must choose whether to stay in the geographic area where they completed their degree or move to a new location to begin their careers. This paper classifies 41 U.S. metropolitan areas as “college towns” and investigates differences in employment outcomes between college graduates who stay in the college town where they obtained their degree and college graduates who leave after completing their degree. We find that college town stayers experience less favorable employment outcomes along multiple dimensions. On average, stayers earn lower annual and hourly wages and work in less educated occupations. J61, R23
Comparative Size Evolution Of Marine Clades From The Late Permian Through Middle Triassic

The small size of Early Triassic marine organisms has important implications for the ecological and environmental pressures operating during and after the end-Permian mass extinction. However, this “Lilliput Effect” has only been documented quantitatively in a few invertebrate clades. Moreover, the discovery of Early Triassic gastropod specimens larger than any previously known has called the extent and duration of the Early Triassic size reduction into question. Here, we document and compare Permian-Triassic body size trends globally in eight marine clades (gastropods, bivalves, calcitic and phosphatic brachiopods, ammonoids, ostracods, conodonts, and foraminiferans). Our database contains maximum size measurements for 11,224 specimens and 2,743 species spanning the Late Permian through the Middle to Late Triassic. The Permian/Triassic boundary (PTB) shows more size reduction among species than any other interval. For most higher taxa, maximum and median size among species decreased dramatically from the latest Permian (Changhsingian) to the earliest Triassic (Induan), and then increased during Olenekian (late Early Triassic) and Anisian (early Middle Triassic) time. During the Induan, the only higher taxon much larger than its long-term mean size was the ammonoids; they increased significantly in median size across the PTB, a response perhaps related to their comparatively rapid diversity recovery after the end-Permian extinction. The loss of large species in multiple clades across the PTB resulted from both selective extinction of larger species and evolution of surviving lineages toward smaller sizes. The within-lineage component of size decrease suggests that only part of the size decrease can be related to the end-Permian kill mechanism; in addition, Early Triassic environmental conditions or ecological pressures must have continued to favor small body size as well. After the end-Permian extinction, size decrease occurred across ecologically and physiologically disparate clades, but this size reduction was limited to the first part of the Early Triassic (Induan). Nektonic habitat or physiological buffering capacity may explain the contrast of Early Triassic size increase and diversification in ammonoids versus size reduction and slow recovery in benthic clades.
β-Boration of α,β-unsaturated carbonyl compounds in ethanol and methanol catalyzed by CCC-NHC pincer Rh complexes

Abstract Quantitative β-boration of α,β-unsaturated carbonyl compounds was achieved utilizing the eco-friendly solvent EtOH along with MeOH at room temperature in 1 h, by a CCC-NHC pincer Rh complex mixture. Substrates with β-substituents were successfully converted yielding challenging, quaternary C–B bonds. The air- and water-stable pre-catalyst A , identified as a mixture of iodo and chloro CCC-NHC pincer Rh amine complexes, was evaluated for catalytic activity. This report is the first example of a pincer Rh complex demonstrating catalytic activity in a 1,4-addition at room temperature.
Nutrition: Beriberi, A Deficiency Related to Grains

Beriberi was most prevalent in the Far East in the late nineteenth century, and was shown to be associated with low-diversity diets based mostly on polished white rice. Pioneering medical research led to the identification of an active factor – later called thiamin – in rice bran, that prevented beriberi. A diverse diet usually provides sufficient thiamin, for example potato and even maize have quite high levels. Fortification of polished rice is also effective. Beriberi can be induced, even in affluent societies with diverse diets, by excessive alcohol consumption. It is also a problem after gastrointestinal surgery if vitamin-deficient parenteral nutrition is applied.
Villains, Victims, and Verisimilitudes: An Exploratory Study of Unethical Corporate Values, Bullying Experiences, Psychopathy, and Selling Professionals’ Ethical Reasoning

This study assesses the relationships among unethical corporate values, bullying experiences, psychopathy, and selling professionals’ ethical evaluations of bullying. Information was collected from national/regional samples of selling professionals. Results indicated that unethical values, bullying, and psychopathy were positively interrelated. Psychopathy and unethical values were negatively associated with moral intensity, while moral intensity was positively related to ethical issue importance. Psychopathy and unethical values were negatively related to issue importance, and issue importance and moral intensity were positively related to ethical judgment. Finally, ethical judgment and moral intensity were positively linked to ethical intention; psychopathy was negatively associated with ethical intention.
Is the world flat?: Differential regulation of domestic and foreign-owned firms

Abstract This paper examines the determinants of differential employment restrictions applied to foreign versus domestic firms. We develop a model of employment regulation and test its implications using data from the World Bank's World Business Environment Survey, conducted in 1999/2000. We find that while democratic accountability, corruption, and British legal origin reduce the extent of government intervention in firms’ employment decision, they give greater advantage to domestic relative to foreign investors. Rule of law, on the other hand, has a more even effect. Better investment opportunities in the country enhance the government's bargaining power vis-a-vis investors and increase employment intervention, especially in foreign firms engaged in less tradable sectors. We also identify a host of other factors that influence employment restrictions, though none of them entail a differential impact on foreign investors. We find that after controlling for other factors, foreign investors in Latin America face a greater regulatory disadvantage vis-a-vis locals compared to other regions of the world, though this is partly counterbalanced by other effects captured in the model.
Semi-autonomous Intersection Collision Avoidance through Job-shop Scheduling

In this paper, we design a supervisor to prevent vehicle collisions at intersections. An intersection is modeled as an area containing multiple conflict points where vehicle paths cross in the future. At every time step, the supervisor determines whether there will be more than one vehicle in the vicinity of a conflict point at the same time. If there is, then an impending collision is detected, and the supervisor overrides the drivers to avoid collision. A major challenge in the design of a supervisor as opposed to an autonomous vehicle controller is to verify whether future collisions will occur based on the current drivers choices. This verification problem is particularly hard due to the large number of vehicles often involved in intersection collision, to the multitude of conflict points, and to the vehicles dynamics. In order to solve the verification problem, we translate the problem to a job-shop scheduling problem that yields equivalent answers. The job-shop scheduling problem can, in turn, be transformed into a mixed-integer linear program when the vehicle dynamics are first-order dynamics, and can thus be solved by using a commercial solver.
Underdevelopment and Economic Theory of Growth: Case for Infant Industry Promotion

The article reviews the literature on economic development, critiques neoliberal economic theories, and advances the theory of infant industry promotion as an alternative model for development in Africa. The essay argues that for developing countries to catch up to developed countries requires contextualizing development theory, applying selective economic policies to industries where productive capacities can be developed, and localizing the policy lessons to develop the productive abilities of local industries. The role of state in development and implementation of protective measures such as tariffs, import bans on key raw materials, and rebates on industrial inputs is discussed. To escape the Resource Curse, African states will have to develop an alternative source of employment, an industrial base, and strengthen the productive powers of infant industries if those industries are to survive fierce international competition. To be durable in the African context, economic policy must reflect local conditions, vary from one historical context to the next, use readily available resources, and adequately respond to local problems. Author’s Note Christopher Zambakari is a candidate for a Law and Policy Doctorate (LPD) at Northeastern University, Boston, Massachusetts. His interest is in political reform, economic development, presence of postcolonial violence, and progress in nation and state building projects in Africa.
The Spectrum in the Sachdev-Ye-Kitaev Model

The SYK model consists of N ≫ 1 fermions in 0 + 1 dimensions with a random, all-to-all quartic interaction. Recently, Kitaev has found that the SYK model is maximally chaotic and has proposed it as a model of holography. We solve the SchwingerDyson equation and compute the spectrum of two-particle states in SYK, finding both a continuous and discrete tower. The four-point function is expressed as a sum over the spectrum. The sum over the discrete tower is evaluated.
Do Get-Out-The-Vote Calls Reduce Turnout? The Importance of Statistical Methods for Field Experiments

In their landmark study of a field experiment, Gerber and Green (2000) found that get-out-the-vote calls reduce turnout by five percentage points. In this article, I introduce statistical methods that can uncover discrepancies between experimental design and actual implementation. The application of this methodology shows that Gerber and Green’s negative finding is caused by inadvertent deviations from their stated experimental protocol. The initial discovery led to revisions of the original data by the authors, and retraction of the numerical results in their article. Analysis of their revised data, however, reveals new systematic patterns of implementation errors. Indeed, treatment assignments of the revised data appear to be even less randomized than before their corrections. To adjust for these problems, I employ a more appropriate statistical method, and demonstrate that telephone canvassing increases turnout by five percentage points. This article demonstrates how statistical methods can find and correct complications of field experiments.
Some pairs problems

A common form of MapReduce application involves discovering relationships between certain pairs of inputs. Similarity joins serve as a good example of this type of problem, which we call a "some-pairs" problem. In the framework of [4], algorithms are measured by the tradeoff between reducer size (maximum number of inputs a reducer can handle) and the replication rate (average number of reducers to which an input must be sent. There are two obvious approaches to solving some-pairs problems in general. We show that no general-purpose MapReduce algorithm can beat both of these two algorithms in the worst case. We then explore a recursive algorithm for solving some-pairs problems and heuristics for beating the lower bound on common instances of the some-pairs class of problems.
Learning and the Effectiveness of Central Bank Forward Guidance

The unconventional monetary policy of forward guidance operates through the management of expectations about future paths of interest rates. This paper examines the link between expectations formation and the effectiveness of forward guidance. A standard New Keynesian model is extended to include forward guidance shocks in the monetary policy rule. Agents form expectations about future macroeconomic variables via either the standard rational expectations hypothesis or a more plausible theory of expectations formation called adaptive learning. The results show the efficacy of forward guidance depends on the manner in which agents form their expectations. In response to forward guidance, the paths of the output gap and inflation under adaptive learning overshoot and undershoot those implied by rational expectations. The adaptive learning impulse responses of the endogenous variables to a forward guidance shock exhibit more persistence before and after the forward guidance shock has been realized upon the economy. During an economic crisis (e.g. a recession), the assumption of rational expectations overstates the effects of forward guidance relative to adaptive learning. Specifically, the output gap is higher under rational expectations than adaptive learning. Thus, if monetary policy is based on a model with rational expectations, which is the standard assumption in the macroeconomic literature, the results of forward guidance could be potentially misleading.
The EpiXCS workbench: a tool for experimentation and visualization

The EpiXCS Workbench is a knowledge discovery tool that provides the user with the capability for knowledge discovery and visualization in medical data. The foundation for the workbench is the XCS paradigm [1]. The workbench is designed to benefit both expert learning classifier systems (LCS) researchers and inexperienced end-users in a variety of domains, especially clinical, epidemiologic, and public health researchers. It was implemented in Microsoft Visual C++, Version 6.0, using the GNU Scientific Library, using the XCSlib class library developed by Lanzi [2]. EpiXCS is designed to run on Intel Pentium processor environments at 1.0GHz and higher. No special graphics or other co-processors are required.
CVXPY: a python-embedded modeling language for convex optimization

CVXPY is a domain-specific language for convex optimization embedded in Python. It allows the user to express convex optimization problems in a natural syntax that follows the math, rather than in the restrictive standard form required by solvers. CVXPY makes it easy to combine convex optimization with high-level features of Python such as parallelism and object-oriented design. CVXPY is available at http://www.cvxpy.org/ under the GPL license, along with documentation and examples.
Early evaluations of the medical home: building on a promising start.

OBJECTIVES To systematically review the current evidence on the patient-centered medical home (PCMH, or medical home), which aims to reinvigorate primary care and achieve the triple aim of better quality, improved experience, and lower costs. STUDY DESIGN Systematic review of quantitative evidence on the PCMH. METHODS Out of 498 studies published or disseminated from January 2000 to September 2010 on US-based interventions, 14 evaluations of 12 interventions met our inclusion criteria: (1) tested a practice-level intervention with 3 or more of 5 key PCMH components and (2) conducted a quantitative study of one of the triple aim outcomes or of healthcare professional experience. We synthesized findings on interventions that were evaluated using rigorous methods. We also provide guidance to structure future evaluations to maximize learning. RESULTS The interventions most often cited to support the medical home can be viewed as precursors to the medical home. Evaluations of 6 of these interventions provided rigorous evidence on 1 or more outcomes. This evidence indicates some favorable effects on all 3 triple aim outcomes, a few unfavorable effects on costs, and many inconclusive results. CONCLUSIONS Although the PCMH is a promising innovation, rigorous quantitative evaluations and comprehensive implementation analyses are needed to assess effectiveness and refine the model to meet stakeholders' needs. Findings from future evaluations will help guide the substantial efforts practices and payers invest to adopt the PCMH with the goal of achieving the triple aim outcomes.
Interbasin Transport of the Meridional Overturning Circulation

AbstractThe meridional overturning circulation (MOC) is studied in an idealized domain with two basins connected by a circumpolar channel in the southernmost region. Flow is forced at the surface by longitude-independent wind stress, freshwater flux, and fast temperature relaxation to prescribed profiles. The only longitudinal asymmetry is that one basin is twice as wide as the other. Two states, a preferred one with sinking in the narrow basin and an asymmetrically forced one with sinking in the wide basin, are compared. In both cases, sinking is compensated by upwelling everywhere else, including the passive basin. Despite the greater area of the wide basin, the residual overturning transport is the same regardless of the location of sinking. The two basins exchange flow at their southern edge by a geostrophic transport balanced by the difference in the depth of isopycnals at the eastern boundaries of each basin. Gnanadesikan’s model for the upper branch of the MOC is extended to include two basins conn...
Gram Schmidt based greedy hybrid precoding for frequency selective millimeter wave MIMO systems

Hybrid analog/digital precoding allows millimeter wave MIMO systems to leverage large antenna array gains while permitting low cost and power consumption hardware. Most prior work has focused on hybrid precoding for narrow-band mmWave systems. MmWave systems, however, will likely operate on wideband channels with frequency selectivity. Therefore, this paper considers frequency selective hybrid precoding with RF beamforming vectors taken from a quantized codebook. For this system, a low-complexity yet near-optimal greedy algorithm is developed for the design of the hybrid analog/digital precoders. The proposed algorithm greedily selects the RF beamforming vectors using Gram-Schmidt orthogonalization. Simulation results show that the developed precoding design algorithm achieves very good performance compared with the unconstrained solutions while requiring less complexity.
Sparsified Cholesky and multigrid solvers for connection laplacians

We introduce the sparsified Cholesky and sparsified multigrid algorithms for solving systems of linear equations. These algorithms accelerate Gaussian elimination by sparsifying the nonzero matrix entries created by the elimination process. We use these new algorithms to derive the first nearly linear time algorithms for solving systems of equations in connection Laplacians---a generalization of Laplacian matrices that arise in many problems in image and signal processing. We also prove that every connection Laplacian has a linear sized approximate inverse. This is an LU factorization with a linear number of nonzero entries that is a strong approximation of the original matrix. Using such a factorization one can solve systems of equations in a connection Laplacian in linear time. Such a factorization was unknown even for ordinary graph Laplacians.
Salient stills

The transformation of a sequence of moving images to a still image presents several problems: a loss of perceived image quality when looking at a single video frame; and a loss of context, since no individual frame captures everything conveyed in a sequence of images. We address these problems by developing a structured representation of moving image data. Using this representation we manipulate the video signal to build salient still frames, including some images with enhanced resolution. We discuss methods of automatically building a structured representation, methods for building salient stills and the potential applications of these images.
The chemistry of the carbon-transition metal double and triple bond: Annual survey covering the year 2014

Abstract This is a review of papers published in the year 2014 that focus on the synthesis, reactivity, or properties of compounds containing a carbon-transition metal double or triple bond.
Fundamental Analysis, Institutional Investment, and Limits to Arbitrage

: Previous research shows that fundamental signals (financial ratios) derived from publicly available financial statements can predict future abnormal stock returns. This paper examines whether institutional investors trade on these fundamental signals and the implications of institutional investors’ trading for stock valuation. We provide evidence that transient institutional investors (institutions who actively trade securities for short-term returns) trade on fundamental signals. We also show that the abnormal returns associated with fundamental signals increase with transaction costs and arbitrage risk, indicating the existence of limits to arbitrage for this investment strategy. We further document that transient institutional investors’ trades help reduce the returns related to fundamental signals. This paper provides evidence helping to explain the abnormal returns associated with fundamental signals and contributes to our understanding of institutional investors’ role in enhancing market efficiency.
Rh-catalyzed 1,4-addition of triallyl(aryl)silanes to α,β-unsaturated carbonyl compounds

Abstract Rh-catalyzed 1,4-addition of triallyl(aryl)silane to α,β-unsaturated carbonyl compounds was developed. Triallyl(aryl)silanes were used as air- and moisture-stable silicon nucleophiles. Allylsilanes were converted to silanols in situ and underwent transmetalation. This method can accept a wide range of functionalized triallyl(aryl)silane and α,β-unsaturated carbonyl compounds.
Theoretical prediction and experimental confirmation of unusual ternary ordered semiconductor compounds in Sr-Pb-S system

We examine the thermodynamics of phase separation and ordering in the ternary CaxPb1–xS and SrxPb1–xS systems by density-functional theory combined with a cluster expansion and Monte Carlo simulations. Similar to most other ternary III–V or IV–VI semiconductor alloys, we find that bulk phase separation is thermodynamically preferred for PbS–CaS. However, we predict the surprising existence of stable, ordered ternary compounds in the PbS–SrS system. These phases are previously unreported ordered rocksalt-based compounds: SrPb3S4, SrPbS2, and Sr3PbS4. The stability of these predicted ordered phases is confirmed by transmission electron microscopy observations and band gap measurements. We believe this work paves the way for a combined theory-experiment approach to decipher complex phase relations in multicomponent chalcogenide systems.
Adaptive contract design for crowdsourcing markets: bandit algorithms for repeated principal-agent problems

Crowdsourcing markets have emerged as a popular platform for matching available workers with tasks to complete. The payment for a particular task is typically set by the task's requester, and may be adjusted based on the quality of the completed work, for example, through the use of "bonus" payments. In this paper, we study the requester's problem of dynamically adjusting quality-contingent payments for tasks. We consider a multi-round version of the well-known principal-agent model, whereby in each round a worker makes a strategic choice of the effort level which is not directly observable by the requester. In particular, our formulation significantly generalizes the budget-free online task pricing problems studied in prior work. We treat this problem as a multi-armed bandit problem, with each "arm" representing a potential contract. To cope with the large (and in fact, infinite) number of arms, we propose a new algorithm, AgnosticZooming, which discretizes the contract space into a finite number of regions, effectively treating each region as a single arm. This discretization is adaptively refined, so that more promising regions of the contract space are eventually discretized more finely. We analyze this algorithm, showing that it achieves regret sublinear in the time horizon and substantially improves over non-adaptive discretization (which is the only competing approach in the literature). Our results advance the state of art on several different topics: the theory of crowdsourcing markets, principal-agent problems, multi-armed bandits, and dynamic pricing.
Asymmetric Construction of Spirocyclopentenebenzofuranone Core Structures via Highly Selective Phosphine-Catalyzed [3 + 2] Cycloaddition Reactions

An efficient organocatalytic asymmetric [3 + 2] cycloaddition reaction between 3-substituted methylenebenzofuranone derivatives and diverse Morita–Baylis–Hillman carbonates to provide complex polysubstituted spirocyclopentenebenzofuranone scaffolds in a single step is reported. C2-symmetric phospholanes were efficient nucleophilic catalysts of this transformation under mild conditions, providing reaction products comprised of three consecutive stereocenters, including one all-carbon center, with excellent enantioselectivity.
Jet-Fuel Cavitation in a Converging-Diverging Nozzle

The focus of this research proposal is the experimental characterization of fuel cavitation in flow through a converging-diverging nozzle. Cavitation of fuel presents additional complexities (as compared to that in water) because fuel is a multi-component mixture. In any practical engineering environment, large quantities of solid microparticles are resident in the fuel. Gas nuclei trapped on these microparticles has been shown to enhance bubble production in water, and their effect on fuel cavitation is an issue that will be investigated. Measurements also will be made with cavitating water for comparison. A converging-diverging nozzle was chosen as the means for producing cavitation because its type of area constriction is similar to other flow devices such as valves and pumps. Cavitating C-D nozzle flows also have been modeled extensively in the literature. The data that will be acquired include axial pressure profiles, nozzle flow rate, high-speed images of the cavitating region, axial void fraction profiles, and axial velocity profiles. Pressure, velocity, and flow rate data will be used to determine the pressure ratios and limiting mass flow rates when the nozzle is choked. High speed images will be used to identify the structures present in the two-phase region (whether the gaseous voids are spherical bubbles or amorphous slugs. Axial void fraction data will provide information on gas evolution in the flow. Experimental data for cavitating nozzle flows are limited to water cases where bubble nucleation is not a primary source of the two-phase mixture. The proposed research hopes to provide detailed pressure, void-fraction, and velocity measurements for comparison with existing models. The main differences between fuel and water cavitation will be highlighted.Copyright © 2007 by ASME
Stereospecific Nickel-Catalyzed Cross-Coupling Reactions of Alkyl Ethers: Enantioselective Synthesis of Diarylethanes

Secondary benzylic ethers undergo stereospecific substitution reactions with Grignard reagents in the presence of nickel catalysts. Reactions proceed with inversion of configuration and high stereochemical fidelity. This reaction allows for facile enantioselective synthesis of biologically active diarylethanes from readily available optically enriched carbinols.
Classifying latent infection states in complex networks

Algorithms for identifying the infection states of nodes in a network are crucial for understanding and containing epidemics and cascades. Often, however, only the infection states of a small set of nodes are known. Moreover, the length of time that each node has been infected is also unknown. This missing data – infection states of most nodes and the infection times of the observed infected nodes – poses a challenge to the study of real-world epidemics/cascades. In this work, we develop techniques to identify the latent infected nodes in the presence of missing infection time-and-state data. Based on likely epidemic paths predicted by a simple susceptible-infected epidemic model, we propose a measure (infection betweenness centrality) for uncovering unknown infection states. We evaluate infection state classifiers based on Naive Bayes, Naive Bayes with kernel density estimation, and decision trees, in combination with features including infection betweenness centrality and different centrality measures. Our experimental results show that among the set of features that include degree and different centrality measures, infection betweenness centrality is the most effective feature for identifying latent infected nodes.
Endorsement, Prior Action, and Language: Modeling Trusted Advice in Computerized Clinical Alerts

The safe prescribing of medications via computerized physician order entry routinely relies on clinical alerts. Alert compliance, however, remains surprisingly low, with up to 95% often ignored. Prior approaches, such as improving presentational factors in alert design, had limited success, mainly due to physicians' lack of trust in computerized advice. While designing trustworthy alert is key, actionable design principles to embody elements of trust in alerts remain little explored. To mitigate this gap, we introduce a model to guide the design of trust-based clinical alerts-based on what physicians value when trusting advice from peers in clinical activities. We discuss three key dimensions to craft trusted alerts: using colleagues' endorsement, foregrounding physicians' prior actions, and adopting a suitable language. We exemplify our approach with emerging alert designs from our ongoing research with physicians and contribute to the current debate on how to design effective alerts to improve patient safety.
Supreme Court Jurisprudence of the Personal in City of Los Angeles v. Patel

Recently, the Supreme Court issued a 5-4 decision in City of Los Angeles v. Patel striking down a city ordinance that required hotel and motel owners to make their guest registries available to police officers whenever requested to do so. Although the Court’s opinion in Patel simply affirmed the Ninth Circuit’s finding that the ordinance was unconstitutional, the Court could have used Patel to readdress the third-party doctrine, which establishes that “a person has no legitimate expectation of privacy in information he voluntarily turns over to third parties.”1 Patel provided a vehicle for the Court to do so, particularly because recent Supreme Court decisions suggest that the Court is concerned about the third-party doctrine’s applicability to broad and warrantless searches of private information. For example, in United States v. Jones, the Court held law enforcement’s use of a GPS tracking device to monitor a suspect’s public movements constituted a search pursuant to the Fourth Amendment.2 Additionally, in Riley v. California, the Court held that, absent exigent circumstances, law enforcement may not search a suspect’s cell phone without a warrant and probable cause.3 In both cases, the Court could have applied the third-party doctrine and held that citizens forfeit any expectations of privacy when they travel in public spaces or transmit information that a third party can access. As evident in Jones and Riley, the Justices value their privacy as much as most people and could have used Patel to further safeguard it when dealing with potential breaches that have real-world possibilities for them. In Part I, this Essay addresses the City of Los Angeles v. Patel case as it presented itself to the Supreme Court from an en banc decision by the U.S.
Housing Satisfaction in Finland with Regard to Area, Dwelling Type and Tenure Status.

Aim: This study presents a comprehensive examination of housing satisfaction in Finland and how it associates with different types of residential area, dwelling and tenure status taking into account socio-demographic and socioeconomic variables. Method: Associations between housing satisfaction and types of residential area, dwelling and tenure status were analysed by multivariate logistic regression using questionnaire data from a random sample of Finnish households (response rate 44%, N=1,308). Results: Respondents from rural areas and those living in houses were statistically significantly (p<0.05) more satisfied with indoor thermal conditions in summer than respondents living in city centres (OR 2.01) and apartments (OR 1.75), respectively. Homeowners were more satisfied with the dwelling (OR 3.19), indoor air quality (OR 1.73) and thermal conditions in winter (OR 2.63), and reported moisture or mould damage (OR 0.37) and neighbour noise disturbance (OR 0.60) less frequently than tenants. Conclusion: Based on this study, the most important factors determining differences in housing satisfaction were tenure status and type of the dwelling. In the context of housing policy development, these results warrant a special consideration of housing quality in rental apartments. The results can also be used for making comparative assessments (e.g. detecting areas of relative strengths or needing improvement) of multifamily buildings and residential areas.
The impact of welfare reform as perceived by users of mental health services in New York City.

A total of 118 psychiatric outpatients, 43 percent of whom were foreign born, completed a 12-item questionnaire about the impact of the new federal welfare legislation. A majority of respondents were worried about the new law and believed that it would worsen their mental symptoms, their well-being, and the quality of life in their neighborhood. Nearly half felt that the law had already affected their mental symptoms. Foreign-born patients were significantly more worried about the law than U.S.-born patients. The results suggest that organized psychiatry and individual psychiatrists should become more involved in activities to diminish the impact of the welfare legislation on patients and their families.
Local and systemic factors in the pathogenesis of osteoporosis.

OSTEOPOROSIS is defined as a decrease in bone mass and strength leading to an increase in fractures, particularly of the vertebral bodies, proximal femur, and distal radius. According to this definition, the disorder must exist before the fracture occurs, but at present we cannot reliably diagnose osteoporosis before a fracture. Moreover, most hip and wrist fractures occur after a fall, and if there is no trauma the osteoporosis may never become clinically apparent. Even in vertebral crush fractures, which usually occur with little or no trauma, the defect in bone mass and strength may exist for years before fracture occurs. . . .
Coherent control using kinetic energy and the geometric phase of a conical intersection

Conical intersections (CIs) between molecular potential energy surfaces with non-vanishing non-adiabatic couplings generally occur in any molecule consisting of at least three atoms. They play a fundamental role in describing the molecular dynamics beyond the Born-Oppenheimer approximation and have been used to understand a large variety of effects, from photofragmentation and isomerization to more exotic applications such as exciton fission in semiconductors. However, few studies have used the features of a CI as a tool for coherent control. Here we demonstrate two modes of control around a conical intersection. The first uses a continuous light field to control the population on the two intersecting electronic states in the vicinity of a CI. The second uses a pulsed light field to control wavepackets that are subjected to the geometric phase shift in transit around a CI. This second technique is likely to be useful for studying the role of nuclear dynamics in electronic coherence phenomena.
“From Contested Concept to Cornerstone of Administrative Practice”: Social Learning and the Early History of U.S. Tax Withholding

The process of establishing a stable and effective system of taxation is a hallmark of nearly all modern states. Indeed, securing the ability to tax is a sine qua non of the historical process of state-building. From ancient Athens to the modern United States, nearly all societies have been concerned with the process of successfully collecting tax revenues. One critical concern that all taxing authorities face is limiting the “tax gap”— the difference between what should be paid voluntarily and on time and the amount that is actually paid. Among the many modern administrative innovations adopted to facilitate effective tax compliance, arguably none has been more significant than the use of thirdparty reporting and tax withholding. Since at least the early nineteenth century, when Great Britain first adopted a crude form of withholding as part of its national income tax, governments have increasingly relied on harnessing the knowledge and power of third parties to increase income tax compliance. As a result, employers, financial institutions, and business corporations have become instrumental remittance vehicles and reporting agents for nearly all modern taxing agencies.
Assessing the inter- and intra-animal variability of in vivo OsteoProbe skeletal measures in untreated dogs.

Abstract The OsteoProbe is a second-generation reference point indentation (RPI) device without a reference probe that is designed to simplify RPI testing for clinical use. Successful clinical implementation of the OsteoProbe would benefit from a better understanding of how its output, bone material strength index (BMSi), relates to the material properties of bone and under what conditions it reliably correlates with fracture risk. Large animal models have the potential to help fill this knowledge gap, as cadaveric studies are retrospective and limited by incomplete patient histories (including the potential use of bone matrix altering drugs such as bisphosphonates). The goal of this study was to assess the intra and inter-animal variability of OsteoProbe measures in untreated beagle dogs (n = 12), and to evaluate this variability in comparison to traditional mechanical testing. OsteoProbe measurements were performed in vivo on the left tibia of each dog and repeated 6 months later on the day of sacrifice. Within-animal variation of BMSi (CV of 5–10 indents) averaged 8.9 and 9.0% at the first and second timepoints, respectively. In contrast, inter-animal variation of BMSi increased from 5.3% to 9.1%. The group variation of BMSi was on par with that of traditional 3-point mechanical testing; inter-animal variation was 10% for ultimate force, 13% for stiffness, and 12% for total work as measured on the femur. There was no significant change in mean BMSi after 6 months, but the individual change with time across the 12 dogs was highly variable, ranging from − 12.4% to + 21.7% (mean 1.6%, SD 10.6%). No significant correlations were found between in vivo tibia BMSi and femur mechanical properties measured by ex vivo 3-pt bending, but this may be a limitation of sample size or the tests being performed on different bones. No relationship was found between BMSi and tissue mineral density, but a strong positive correlation was found between BMSi and tibia cortical thickness (ρ = 0.706, p = 0.010). This report shows that while the OsteoProbe device has inter-individual variability quite similar to that of traditional mechanical testing, the longitudinal changes show high levels of heterogeneity across subjects. We further highlight the need for standardization in post-testing data processing and further study of the relationships between OsteoProbe and traditional mechanical testing.
PERFORMING A PRIMARY HIP ARTHROPLASTY

This session will be practically oriented, focusing on important surgical decisions and on technical tips to avoid complications. The panel will be polled concerning individual preferences as regards the following issues in primary total hip arthroplasty: 1. Peri-operative antibiotics/blood management/preferred anesthetics; 2. Surgical approach for primary total hip arthroplasty: indications or preferences for direct anterior, anterolateral, posterior; 3. Acetabular fixation; 4. Tips for optimizing acetabular component orientation; 5. Femoral fixation: (a) Indications for cemented and uncemented implants. (b) Role of hip resurfacing; 6. Femoral head size: Preferred head sizes in different situations; 7. Bearing surface: Present role of different bearings; 8. Tips for optimizing intra-operative hip stability; 9. Tips for optimizing leg length; 10. Post-operative venous thromboembolism prophylaxis; 11. Heterotopic bone prophylaxis; 12. Post-operative pain management; 13. Post-operative rehabilitation protocol: weight bearing, role of physical therapy; 14. Post-operative activity restrictions; and 15. Post-operative antibiotic prophylaxis for procedures.
Competitively Scheduling Tasks with Intermediate Parallelizability

We introduce a scheduling algorithm Intermediate-SRPT, and show that it is O(logP)-competitive with respect to average flow time when scheduling jobs whose parallelizability is intermediate between being fully parallelizable and sequential. Here, the parameter P denotes the ratio between the maximum job size to the minimum. We also show a general matching lower bound on the competitive ratio. Our analysis builds on an interesting combination of potential function and local competitiveness arguments.
Near-optimum control of multiple-access collision channels

A method based on recursive computation of the expected number of attempts and successes during the collision resolution phase of an access control algorithm is introduced for the design of near-optimum control strategies for multiple access collision channels with ternary and binary feedback. With this approach it is possible to circumvent the extremely difficult and still unsolved problem of finding the access control algorithm which achieves the highest throughput by settling for a near-optimum solution. The key to the design of the algorithms is to approximate the originally infinite-dimensional optimization problem by a one-dimensional optimization problem. In the ternary feedback case, the proposed algorithm achieves a throughput virtually identical to the highest throughput reported. Several forms of binary feedback are considered, and algorithms are introduced that achieve the highest throughput reported. >
A computer-aided treatment planning technique for universal wedges

Some modern accelerators provide only one wedge built into the head of the treatment machine. A continuous range of wedge angles can be generated using wedged and unwedged beams in different proportions. However, this may pose difficulty in treatment planning since the planners will have to work with twice as many beams to achieve a desirable dose distribution. We have developed a simple algorithm to solve the treatment planning problem involving wedged and open beam combinations. The algorithm is based on the assumption that the user has some knowledge of the dose distribution to be optimized. Some properties of the distributions are then used to set up the system of equations for optimization. Unlike other optimization techniques, it does not require specification of dose value to every interest point selected, and it allows each specified dose value to vary within a clinically acceptable range. Examples are given to illustrate the application of the algorithm for some standard treatment plans.