cssi/SciSciGPT-SciSciNet huggingface dataset:
Strategic Seeding of Rival Opinions

We present a network influence game that models players strategically seeding the opinions of nodes embedded in a social network. A social learning dynamic, whereby nodes repeatedly update their opinions to resemble those of their neighbors, spreads the seeded opinions through the network. After a fixed period of time, the dynamic halts and each player’s utility is determined by the relative strength of the opinions held by each node in the network vis-a-vis the other players. We show that the existence of a pure Nash equilibrium cannot be guaranteed in general. However, if the dynamics are allowed to progress for a sufficient amount of time so that a consensus among all of the nodes is obtained, then the existence of a pure Nash equilibrium can be guaranteed. The computational complexity of finding a pure strategy best response is shown to be \(\mathrm {NP}\)-complete, but can be efficiently approximated to within a \((1 - 1/e)\) factor of optimal by a simple greedy algorithm.
Engineering permanence in finite systems

The man-machine integration era (MMIE) is marked by sensor ubiquity, whose readings map human beings to finite numbers. These numbers—processed by continuously changing, optimizing/learning, finite precision, closed loop, distributed systems—are used to drive decisions such as insurance rates, prison sentencing, health care allocations and probation guidelines. Optimization and system parameter tuning is increasingly left to machine learning and applied AI. One challenge we face is thus: Ensuring the indelibility, the permanence, the infinite value of human beings as optimizationresistant invariants in such system environments. In this challenge paper, we propose developing safeguards, specifically working towards a ‘deontological imprimatur’ architecture embedding resilient representations of human beings.
Independent and Affiliated Analysts: Disciplining and Herding

ABSTRACT: The paper investigates strategic interactions between an independent analyst and an affiliated analyst in the context of issuing stock recommendations. Compared to the independent analyst, the affiliated analyst has superior information, but faces a conflict of interest. I show that the independent analyst disciplines the affiliated analyst's biased forecasting behavior. Meanwhile, the independent analyst sometimes herds with the affiliated analyst to improve his recommendation accuracy. Because of the affiliated analyst's conflict of interest, the value the independent analyst expects to derive from his ex post herding option is endogenous and can motivate him to acquire more information up front. As a result, herding and disciplining not only coexist, but also mutually reinforce each other. That is, there is an endogenous complementarity between the independent analyst's ex ante disciplining role and his ex post herding behavior in equilibrium.
Near Threshold Effects on Recombination and Vibrational Relaxation in Efimov Systems

We investigate the energy dependence of inelastic processes in systemswhich possess Efimov states. We consider the three-body recombinationrate $K_3$ where three free atoms interact to produce anatom--dimer pair, and the relaxation rate $K_{\rm rel}$where an atom quenches a weakly bound state of a dimernear an Efimov resonance to more deeply bound levels.Using a modelcapturing the key features of the Efimov problem, weidentify new energy regimes for $K_3$, namely the NTR (NearThreshold Resonance) regime behavior $E^{-2}$ for negativescattering lengths and the NTS (Near Threshold Suppression) regimebehavior $E^2$ for positive scattering lengths.We also confirm apreviously found oscillatory behavior of $K_3$ at higher energy$E$. Finally, we find that $K_{\rm rel}$ behaves as $E^{-1}$ in theNTR regime.
Truthful Mechanisms for Matching and Clustering in an Ordinal World

We study truthful mechanisms for matching and related problems in a partial information setting, where the agents' true utilities are hidden, and the algorithm only has access to ordinal preference information. Our model is motivated by the fact that in many settings, agents cannot express the numerical values of their utility for different outcomes, but are still able to rank the outcomes in their order of preference. Specifically, we study problems where the ground truth exists in the form of a weighted graph of agent utilities, but the algorithm can only elicit the agents' private informatison in the form of a preference ordering for each agent induced by the underlying weights. Against this backdrop, we design truthful algorithms to approximate the true optimum solution with respect to the hidden weights. Our techniques yield universally truthful algorithms for a number of graph problems: a 1.76-approximation algorithm for Max-Weight Matching, 2-approximation algorithm for Max k-matching, a 6-approximation algorithm for Densest k-subgraph, and a 2-approximation algorithm for Max Traveling Salesman as long as the hidden weights constitute a metric. Our results are the first non-trivial truthful approximation algorithms for these problems, and indicate that in many situations, we can design robust algorithms even when the agents may lie and only provide ordinal information instead of precise utilities.
Magnetic properties of low-moment ferrimagnetic Heusler Cr2CoGa thin films grown by molecular beam epitaxy

Recently, theorists have predicted many materials with a low magnetic moment and large spin-polarization for spintronic applications. These compounds are predicted to form in the inverse Heusler structure; however, many of these compounds have been found to phase segregate. In this study, ordered Cr2CoGa thin films were synthesized without phase segregation using molecular beam epitaxy. The present as-grown films exhibit a low magnetic moment from antiferromagnetically coupled Cr and Co atoms as measured with superconducting quantum interface device magnetometry and soft X-ray magnetic circular dichroism. Electrical measurements demonstrated a thermally-activated semiconductor-like resistivity component with an activation energy of 87 meV. These results confirm spin gapless semiconducting behavior, which makes these thin films well positioned for future devices.
FIRING COSTS AND CAPITAL STRUCTURE DECISIONS

I exploit the adoption of state-level labor protection laws as an exogenous increase in employee firing costs to examine how the costs associated with discharging workers affect capital structure decisions. I find that firms reduce debt ratios following the adoption of these laws, with this result stronger for firms that experience larger increases in firing costs. I also document that, following the adoption of these laws, a firm's degree of operating leverage rises, earnings variability increases, and employment becomes more rigid. Overall, these results are consistent with higher firing costs crowding out financial leverage via increasing financial distress costs.
A Data Structure for Nearest Common Ancestors with Linking

Consider a forest that evolves via link operations that make the root of one tree the child of a node in another tree. Intermixed with link operations are nca operations, which return the nearest common ancestor of two given nodes when such exists. This article shows that a sequence of m such nca and link operations on a forest of n nodes can be processed online in time O(mα (m,n)+n). This was previously known only for a restricted type of link operation.The special case where a link only extends a tree by adding a new leaf occurs in Edmonds’ algorithm for finding a maximum weight matching on a general graph. Incorporating our algorithm into the implementation of Edmonds’ algorithm in [9] achieves time O(n(m + nlog n)) for weighted matching, an arguably optimum asymptotic bound (n and m are the number of vertices and edges, respectively). Our data structure also provides a simple alternative implementation of the incremental-tree set merging algorithm of Gabow and Tarjan [11].
Pre-diagnostic and Diagnostic Stages of Autism Spectrum Disorder: A Parent Perspective

ABSTRACTThis study examined the experiences of parents receiving an autism spectrum disorder (ASD) diagnosis for their child. Mixed methods were used to give a detailed account of the sequence of events, parents’ experiences and actions associated with the ASD diagnosis. Parents waited nearly two and a half years (mean = 28.72 months) before receiving the ASD diagnosis. Parents with lower general and autism-specific social support, poorer physical health functioning and children with more severe communication problems reported longer wait times. Surprisingly, parents reported more positive than negative experiences from receiving the diagnosis. Paediatricians and psychologists were consulted most frequently; paediatricians and general physicians were rated most likely to neglect early ASD symptoms and least likely to make appropriate referrals. Qualitative analyses revealed seven themes describing the parent experience during the diagnostic process: “heightened awareness”, “initial search”, “dissatisfacti...
Explaining Socially Responsible Consumer Behavior: A Meta-Analytic Review of Theory of Planned Behavior

ABSTRACTThis study reviews previous studies on socially responsible consumers and identifies major antecedents of behavioral intentions to contribute to the theoretical understanding of their purchase behaviors. Meta-analytic procedures were used to (1) quantify the relationship between theory of planned behavior (TPB) constructs, (2) examine the contribution of additional predictors to explain behavioral intention, and (3) identify moderators that influence the strength of the relationships between TPB constructs. The results reveal key factors underlying the consumer decision-making process and provide useful information for marketers in developing strategies that can increase acceptance and purchase of products/services that address consumers' ethical concerns.
USE OF CONSTRAINED SOCKETS IN REVISION THA: MORE PROBLEMS THAN THEY SOLVE – OPPOSES

A well designed constrained liner does not have a “hood” nor a wide poly brim that extends beyond the metal shell because these cause impingement. The failure of a good design is almost always technique. Size the liner so the poly is press fit against the metal rim of the cup. Cement thickness does not matter. Remove any derotation tabs on metal rim with a carbide burr so there is a firm press fit with no toggle. Do NOT angle the poly to change the anteversion. Use the carbide burr to scratch the inner surface of the cup and a soft tissue burr to scratch the backside of the poly. Cement must be liquid enough to fully seat the poly against the metal rim. If cement too doughy it resists full seating. Put metal ring in groove during implantation and cementing to prevent cement into the groove. If this is a primary cup use screws with the cup or cement the poly into the acetabular bone. Dry the head and inner surface of the poly to facilitated reduction. Align the head concentrically into the mouth of the poly and push simultaneously on the knee and over the greater trochanter.
Frege proof system and TNC

A Frege proof system F is any standard system of propositional calculus, e.g., a Hilbert style system based on finitely many axiom schemes and inference rules. An Extended Frege system EF is obtained from F as follows. An EF-sequence is a sequence of formulas y',, . . ., k such that each Vti is either an axiom of F, inferred from previous yV, and Vrv (= -+ Vi) by modus ponens or of the form q <p, where q is an atom occurring neither in p nor in any of VI' . ..., Vi 1 Such q <p , is called an extension axiom and q a new extension atom. An EF-proof is any EF-sequence whose last formula does not contain any extension atom. In [12], S. A. Cook and R. Reckhow proved that the pigeonhole principle PHP has a simple polynomial size EF-proof and conjectured that PHP does not admit polynomial size F-proof. In [5], S. R. Buss refuted this conjecture by furnishing polynomial size F-proof for PHP. Since then the important separation problem of polynomial size F and polynomial size EF has not shown any progress. In [1 1], 5S. A. Cook introduced the system PV, a free variable equational logic whose provable functional equalities are 'polynomial time verifiable' and showed that the metamathematics of F and EF can be developed in P V and the soundness of EF proved in P V. In [3], 5S. R. Buss introduced the first order system S and showed that S' is essentially a conservative extension of P V. There he also introduced a second order system VI' (BD). In [23] we proved that S and VI' (BD) are isomorphic under the so-called RSUV Isomorphism. In [17], J. Krajicek proved that a proof in V,' (BD) more precisely lb -part of V11(BD) is simulated in polynomial size EF-proof and therefore that a proof in S' (more precisely Lb-part of S ) can be simulated by a polynomial size EF-proof. In Clote-Takeuti [10], we introduced a first order system TNC0 which corresponds to the computational complexity class NC'. We also introduced another first order system T0NC0 which is equivalent to TNC0. In this paper we first develop the metamathematics of F and EF in TNC0 and prove the soundness of F in TNC0. Then we show that a proof in T0NC0 is simulated by a sequence of polynomial size. We actually prove a stronger statement. Let no be the number of propositional variables in an F-proof or an EF-proof. Let f be an NC' -function defined in TNC0 such that TNC0 proves that f (a) is an F-proof (or an EF-proof) of its conclusion g(a) where a = 2n0. If we substitute
Dictionary Learning-Based Sparse Channel Representation and Estimation for FDD Massive MIMO Systems

This paper addresses the problem of uplink (UL) and downlink (DL) channel estimation in frequency-division duplexing (FDD) massive multiple-input multiple-output (MIMO) systems. By utilizing the sparse recovery and compressive sensing algorithms, we are able to improve the accuracy of the UL/DL channel estimation and reduce the number of UL/DL pilot symbols. Such successful channel estimation builds upon the assumption that the channel can be sparsely represented under some basis/dictionary. Previous works model the channel using some predefined basis/dictionary; while in this paper, we present a dictionary learning-based channel model such that a dictionary is learned from comprehensively collected channel measurements. The learned dictionary adapts specifically to the cell characteristics and promotes a more efficient and robust channel representation, which in turn improves the performance of the channel estimation. Furthermore, we extend the dictionary learning-based channel model into a joint UL/DL learning framework by observing the reciprocity of the angle of arrival/angle of departure between the UL/DL transmissions and propose a joint channel estimation algorithm that combines the UL and DL received training signals to obtain a more accurate channel estimate. In other words, the DL training overhead, which is a bottleneck in FDD massive MIMO system, can be reduced by utilizing the information from simpler UL training.
Unsupervised learning of HTNs in complex adversarial domains

While Hierarchical Task Networks are frequently cited as flexible and powerful planning models, they are often ignored due to the intensive labor cost for experts/programmers, due to the need to create and refine the model by hand. While recent work has begun to address this issue by working towards learning aspects of an HTN model from demonstration, or even the whole framework, the focus so far has been on simple domains, which lack many of the challenges faced in the real world such as imperfect information and realtime environments. I plan to extend this work using the domain of real-time strategy (RTS) games, which have gained recent popularity as a challenging and complex domain for AI research.
QUATERNIONIC QUANTUM FIELD THEORY

We show that a quaternionic quantum field theory can be formulated when the numbers of bosonic and fermionic degrees of freedom are equal and the fermions, as well as the bosons, obey a second order wave equation. The theory takes the form of either a functional integral with quaternion-imaginary Lagrangian, or a Schrodinger equation and transformation theory for quaternion-valued wave functions, with a quaternion-imaginary Hamiltonian. The connection between the two formulations is developed in detail, and many related issues, including the breakdown of the correspondence principle and the Hilbert space structure, are discussed.
ARE ALL CEMENTLESS STEMS CREATED EQUAL

In recent years, cementless stems have dominated the North American market. There are several categories of cementless stems, but in the past 20 years, the two most popular designs in the United States have been the extensively coated cylindrical cobalt-chrome (CoCr) stem and the proximally coated tapered titanium stem, which in recent years has become the most common. The 10 year survival for both stem types has been over 95% with a distinction made on factors other than stem survival, including thigh pain, stress shielding, complications of insertion, and ease of revision. Conventional wisdom holds that proximally coated titanium stems have less stress shielding, less thigh pain, and a higher quality clinical result. Recent studies, however, including randomised clinical trials have found that the incidence of thigh pain and clinical result is essentially equivalent between the stem types, however, there is a modest advantage in terms of stress shielding for a tapered titanium stem over an extensively coated CoCr stem. One study utilising pain drawings did establish that if a CoCr cylindrical stem was utilised, superior clinical results in terms of pain score and pain drawings were obtained with a fully coated versus a proximally coated stem. In spite of the lack of a clinically proven advantage in randomised trials, tapered titanium stems have been favored because of the occasional occurrence of substantial stress shielding, the increased clinical observation of thigh pain severe enough to warrant surgical intervention, ease of use of shorter tapered stems that involves removal of less trochanteric bone and less risk of fracture both at the trochanter and the diaphysis due to the shorter, and greater ease of insertion through more limited approaches, especially anterior approaches. When tapered stems are utilised, there may be an advantage to a more rectangular stem-cross section in patients with type C bone. In spite of the numerous clinical advantages of tapered titanium stems, there still remains a role for more extensively coated cylindrical stems in patients that have had prior surgery of the proximal femur, particularly for a hip fracture, which makes proximal fixation, ingrowth, and immediate mechanical stability difficult to assure consistently. Cement fixation should also be considered in these cases. While the market place and the clinical evidence strongly support routine use of tapered titanium proximally coated relatively short stems with angled rather than straight proximal lateral geometry in the vast majority of cases, there still remains a role for more extensively coated cylindrical and for specific indications.
Change in Mandibular Position in Patients With Syndromic Craniosynostosis After Midfacial Advancement With Distraction Osteogenesis.

OBJECTIVE Characterize mandibular morphology in patients with syndromic craniosynostosis and document changes in mandibular position following midfacial advancement using distraction osteogenesis (DO). DESIGN Retrospective chart review and analysis of cephalometric radiographs. SETTING Tertiary care center. PATIENTS Patients with syndromic craniosynostosis who had midfacial advancement with DO at Boston Children's Hospital between 2000 and 2012. Mandibular morphology was characterized in 26 patients (15 boys and 11 girls) with a mean age of 11 years, 9 months. Pre- and postoperative analyses were performed for 17 (10 boys and 7 girls) of the 26 patients with a mean age of 11 years, 9 months. MAIN OUTCOME MEASURES Mandibular morphology and mandibular position. Data were compared to standard data from the Michigan Growth Study. RESULTS Comparison of preoperative mandibular measurements to standard data showed that patients with syndromic craniosynostosis have a shorter mandibular body and length and an obtuse gonial angle. Comparison of pre- and postoperative cephalograms showed that, following midfacial advancement with DO, the maxilla moved forward and the mandible moved backward and downward. CONCLUSIONS Patients with syndromic craniosynostosis have a smaller mandible length and obtuse gonial angle. Correction of midfacial hypoplasia with DO results in inferior and posterior mandibular movement. Clinicians can use this information to counsel patients regarding anticipated changes in facial profile and the need for adjunct procedures.
Glutathione‐S‐transferase P1 may predispose children to a decline in pulmonary function after stem cell transplant

RATIONALE Pulmonary complications after hematopoietic stem cell transplant (SCT) are associated with increased mortality. Genetic markers for those at risk for pulmonary impairment post-SCT have not been widely investigated. METHODS Forty-nine patients were retrospectively selected from a single institution's biorepository with linked clinical data. All subjects performed pre-SCT PFTs. Genotyping was conducted using the Infinium Exome-24 BeadChip. Four single nucleotide polymorphisms (SNPs) were selected (rs1800871, rs1695, rs1800629, rs12477314) and evaluated for association with PFT parameters as change over time from baseline. Associations between SNPs and PFT parameters were assessed and adjusted for the following confounding variables: age, gender, and race. RESULTS Using the recessive genetic model, patients with one or two minor alleles for the glutathione S-transferase P1 (GSTP1) SNP rs1695 had a lower decline in FEV1 and FEF25-75 at 1-year post-SCT compared to patients who were homozygous for the ancestral allele (adjusted P-values <0.01 and 0.02, respectively). No other SNPs were significantly associated with other PFT parameters. CONCLUSIONS Our findings suggest that GSTP1 genotype may be associated with lung function during the first year post-SCT. Identifying and investigating genes that predispose patients to pulmonary complications after SCT may allow for more personalized patient management based on pre-emptive genetic testing. The glutathione S-transferase gene merits further investigation.
Return seasonality in the foreign exchange market

ABSTRACTI examine return seasonality in the foreign exchange market using currency futures during the period 1973−2015. All the G10 currency futures yield negative returns in January and this effect happens more often in the countries that have a tax year ending in December. In contrast, returns offered in April are positive. To exploit these anomalies, I use a seasonality strategy that selects portfolios based on their historical same-calendar-month returns. I find that this strategy does not work in the currency market, although I find consistent results with Keloharju et al. in the stock portfolios.
On the dynamics of metal cutting with nonlinearities and time delays

Two models for metal machining dynamics are studied. One of them is of non-linear type and the other is linear. State space representations are formed and then phase plane depictions of the dynamic behaviours are given. The nature of these dynamics is discussed as a representative property of the corresponding models. A very important issue, the stability, is addressed next with the presence of varying time arguments for the state vector. For this question, a frequency domain analysis and an abstract mathematical approach are compared.
Constraint Identification and Algorithm Stabilization for Degenerate Nonlinear Programs

In the vicinity of a solution of a nonlinear programming problem at which both strict complementarity and linear independence of the active constraints may fail to hold, we describe a technique for distinguishing weakly active from strongly active constraints. We show that this information can be used to modify the sequential quadratic programming algorithm so that it exhibits superlinear convergence to the solution under assumptions weaker than those made in previous analyses.
Broadband material model identification with GMS-parameters

Design and compliance analysis of PCB and packaging interconnects for 10–50 Gbps and higher data rates should begin with the identification of broadband dielectric and conductor roughness models. Such models are not available from manufacturers and the model identification is the most important element of successful interconnect design. Broadband model identification with generalized modal S-parameters (GMS-parameters) is outlined and compared with the standardized Short Pulse Propagation (SPP) technique. Practical examples of successful dielectric and conductor roughness model identification up to 50 GHz are also provided.
Explaining Causal Findings Without Bias: Detecting and Assessing Direct Effects

Researchers seeking to establish causal relationships frequently control for variables on the purported causal pathway, checking whether the original treatment effect then disappears. Unfortunately, this common approach may lead to biased estimates. In this article, we show that the bias can be avoided by focusing on a quantity of interest called the controlled direct effect. Under certain conditions, the controlled direct effect enables researchers to rule out competing explanations—an important objective for political scientists. To estimate the controlled direct effect without bias, we describe an easy-to-implement estimation strategy from the biostatistics literature. We extend this approach by deriving a consistent variance estimator and demonstrating how to conduct a sensitivity analysis. Two examples—one on ethnic fractionalization’s effect on civil war and one on the impact of historical plough use on contemporary female political participation—illustrate the framework and methodology.
Structural analysis technology for high-temperature design☆

Abstract Results from an ongoing program devoted to the development of verified high-temperature structural design technology applicable to nuclear reactor systems are described. The major aspects addressed by the program are (1) deformation behavior; (2) failure associated with creep rupture, brittle fracture, fatigue, creep-fatigue interactions, and crack propagation; and (3) the establishment of appropriate design criteria. This paper discusses information developed in the deformation behavior category. The material considered is type 304 stainless steel, and the temperatures range to 1100° F (593° C). In essence, the paper considers the ingredients necessary for predicting relatively high-temperature inelastic deformation behavior of engineering structures under time-varying temperature and load conditions and gives some examples. These examples illustrate the utility and acceptability of the computational methods identified and developed for predicting essential features of complex inelastic behaviors. Conditions and responses that can be encountered under nuclear reactor service conditions and invoked in the examples.
Geographic and socio-economic barriers to rural electrification: New evidence from Indian villages☆

The International Energy Agency estimates that more than a billion people remain without household electricity access. However, countries such as India have recently made major progress in rural electrification. Who has benefited from these achievements? We focus on 714 villages in six energy-poor states of northern and eastern India to investigate trends in electricity access. We use data both from the 2011 Census of India and an original energy access survey conducted in 2014 and 2015. During the three years that separated the surveys, distance to the nearest town and land area lose their power as predictors of the percentage of households in the village that has access to electricity. In this regard, the Indian government's flagship rural electrification program seems to have managed to overcome a major obstacle to grid extension. On the other hand, socio-economic inequalities between villages related to caste status and household expenditure remain strong predictors. These findings highlight the importance of socio-economic barriers to rural electricity access and alleviate concerns about remoteness and population density as obstacles to grid extension.
ELECTROCAUTERY-INDUCED DAMAGE TO TI-6AL-4V AND COCRMO ALLOY SURFACES IN VIVO AND IN VITRO: AN ADDITIONAL DAMAGE SOURCE TO INFLAMMATORY CELL-INDUCED CORROSION

Recently, our lab has made observations of metal damage patterns from retrieval studies that appeared to be cellular in nature [1]. This type of damage presented on about 74% of the retrieved implants and was attributed to inflammatory cells (termed ICI corrosion) [1]. An alternate hypothesis arose surrounding the use of electrosurgery in total joint arthroplasty (TJA). In TJA, where surgery occurs around metallic devices, the interactions of the high voltage, high frequency current created by an electrosurgical generator and the implant need to be better understood. In order to explore the effects electrosurgical currents have on metal implants, the interaction of a model system of highly polished metal disks and a standard electrosurgical generator (ConMed, Utica, NY) was evaluated in various modes and power settings. The disks were made of CoCrMo or Ti-6Al-4V alloys and were polished to a mirror finish for use and placed directly on the return electrode pad used in patients. Both coagulation and cut modes were evaluated, as well as both monopolar and bipolar configurations in wet and dry conditions using a blade-shaped tip. In wet cases, the disks were wet with phosphate buffered saline prior to the test to simulate body fluids in contact with the implant during current application. In all cases, surface damage was generated on both surfaces and was readily observed as a direct result of the current interacting with the metal (Fig. 1 and 2). Direct contact with the metal, regardless of a dry or wet surface, resulted in pitting and oxide buildup at the contact area. Non-contact activation in proximity to the surface or contact with fluid on the surface caused arcing and created damage that was more widespread over the area of fluid contact with the surface. The damage patterns created on the wetted surface by the electrosurgical unit looked very similar to the patterns we previously attributed to inflammatory cells. More specifically, it produced circular, ruffled areas with centralized pits and occasionally presented trail- and weld-like features (Fig. 2). While these results show that some of the damage previously reported to be from ICI corrosion is indeed the result of electrosurgery, there are still cases in retrievals that cannot be explained by this process and the corrosion reaction to alloys exposed to ROS-based molecules demonstrate significant acceleration of corrosion. Thus, ICI corrosion is still a viable hypothesis. Surgeons utilizing electrosurgical systems in proximity to metallic orthopedic implants need to exercise caution as the discharge of electrical energy through these implants can induce localized surface damage and may result in other adverse effects to the metal implants. Ultimately, we would like to update the community on the nature of the damage we previously reported and more importantly bring to light the possibility of surgeon-induced damage to the implant as a result of electrosurgical methods.
The effect of mobile device use and headline focus on investor judgments

Abstract This study conducts two experiments to examine how investors’ judgments differ when they read a press release using either a mobile device or a computer. Results show that when investors use a mobile device, information related to a specific headline (mentioning a specific part of the news like “net income” or “revenue”) influences their investment judgments more than when investors use a computer. This effect is robust to specific headlines that focus on either positive or negative information. In contrast, investors’ judgments do not differ when they use a mobile device compared to a computer and the headline is general (using the broad term “results”). We replicate our findings in a second experiment and provide evidence that the observed effect occurs because investors who use their mobile device are in a more distracted frame of mind, which in turn increases the influence of prominent information. Our results suggest that managers’ presentation choices may have a greater influence on investors as they increasingly rely on mobile devices to research and execute investment decisions.
Portfolio-driven Resource Management for Transient Cloud Servers

Cloud providers have begun to offer their surplus capacity in the form of low-cost transient servers, which can be revoked unilaterally at any time. While the low cost of transient servers makes them attractive for a wide range of applications, such as data processing and scientific computing, failures due to server revocation can severely degrade application performance. Since different transient server types offer different cost and availability tradeoffs, we present the notion of server portfolios that is based on financial portfolio modeling. Server portfolios enable construction of an "optimal" mix of severs to meet an application's sensitivity to cost and revocation risk. We implement model-driven portfolios in a system called ExoSphere, and show how diverse applications can use portfolios and application-specific policies to gracefully handle transient servers. We show that ExoSphere enables widely-used parallel applications such as Spark, MPI, and BOINC to be made transiency-aware with modest effort. Our experiments show that allowing the applications to use suitable transiency-aware policies, ExoSphere is able to achieve 80% cost savings when compared to on-demand servers and greatly reduces revocation risk compared to existing approaches.
Ethical considerations for involving Latina adolescents in mental health research

Topic US Latina adolescents experience significant mental health disparities, such as depressive symptoms and suicidal ideation and, therefore, should be involved in research studies focused on minimizing these health disparities. However, researchers must consider the specific ways this population is vulnerable and provide adequate protections to reduce risks related to these vulnerabilities. Purpose The purpose of this article is to describe the different ways that Latina adolescents with mental health problems can be vulnerable research participants, identify strategies to protect this population during a research study, and describe steps taken to apply these strategies in an ongoing qualitative study examining depression in Latina adolescents. Sources Used Kipnis's (2003) article describes seven ways that children can be vulnerable research participants. These seven vulnerabilities are used to describe the vulnerabilities of Latina adolescents with mental health problems. Specific strategies to protect this population are synthesized to provide a list of strategies that can be used by researchers to reduce the risks associated with the vulnerabilities of this group. Conclusions In order to minimize risks for Latina adolescents, researchers must be engaged in Latino/a communities, use culturally and linguistically appropriate consent processes, and implement strategies to protect the confidentiality of Latina adolescent participants.
Location Privacy Preservation in Database-Driven Wireless Cognitive Networks Through Encrypted Probabilistic Data Structures

In this paper, we propose new location privacy preserving schemes for database-driven cognitive radio networks that protect secondary users’ (SUs) location privacy while allowing them to learn spectrum availability in their vicinity. Our schemes harness probabilistic set membership data structures to exploit the structured nature of spectrum databases (DBs) and SUs’ queries. This enables us to create a compact representation of DB that could be queried by SUs without having to share their location with DB, thus guaranteeing their location privacy. Our proposed schemes offer different cost-performance characteristics. Our first scheme relies on a simple yet powerful two-party protocol that achieves unconditional security with a plausible communication overhead by making DB send a compacted version of its content to SU which needs only to query this data structure to learn spectrum availability. Our second scheme achieves significantly lower communication and computation overhead for SUs, but requires an additional architectural entity which receives the compacted version of the database and fetches the spectrum availability information in lieu of SUs to alleviate the overhead on the latter. We show that our schemes are secure, and also demonstrate that they offer significant advantages over existing alternatives for various performance and/or security metrics.
Labor market discrimination and sorting: Evidence from South Africa

This paper collects a unique data set of classified ads and exploits quasi-random variation in the applicant pool composition to test for hiring discrimination against immigrants in South Africa's informal sector. Consistent with a tournament models in which immigrants are penalized, the analysis finds that foreigners and natives benefit from being pooled with foreign job seekers. Next, the paper tests whether discrimination affects search behavior. Controlling for location fixed effects, the analysis finds suggestive evidence for sorting: immigrants search further away and higher discrimination in the residential area is positively correlated with the decision to search in different suburbs.
Gallman Revisited: Blacksmithing and American Manufacturing, 1850-1870

In nineteenth-century America, blacksmiths were a fixture in every village, town, and city, producing a diverse range of products from axes to wheels and services from repairs to horse shoeing. In constructing his historical GNP accounts, Gallman opted to exclude these “jacks-of-all-trades” from the manufacturing sector, classifying them instead as part of the service sector. However, using establishment-level data for blacksmiths from the federal censuses of manufactures for 1850, 1860, and 1870, we re-examine that choice and show that blacksmiths were an important, if declining, source of manufactured goods. Moreover, as quintessential artisan shops, a close analysis of their structure and operation helps resolve several key puzzles regarding industrialization in the nineteenth century. As “jacks-of-all-trades,” they were generally masters of none (except for their service activities). Moreover, the historical record reveals that several of those who managed to achieve mastery moved on to become specialized manufacturers of that specific product. Such specialized producers had higher productivity levels than those calling themselves blacksmiths producing the same goods, explaining changes in industry mix and the decline of the blacksmith in manufacturing.
Etiology and clinical presentation of birth defects: population based study.

Objective To assess causation and clinical presentation of major birth defects. Design Population based case cohort. Setting Cases of birth defects in children born 2005-09 to resident women, ascertained through Utah’s population based surveillance system. All records underwent clinical re-review. Participants 5504 cases among 270 878 births (prevalence 2.03%), excluding mild isolated conditions (such as muscular ventricular septal defects, distal hypospadias). Main outcome measures The primary outcomes were the proportion of birth defects with a known etiology (chromosomal, genetic, human teratogen, twinning) or unknown etiology, by morphology (isolated, multiple, minors only), and by pathogenesis (sequence, developmental field defect, or known pattern of birth defects). Results Definite cause was assigned in 20.2% (n=1114) of cases: chromosomal or genetic conditions accounted for 94.4% (n=1052), teratogens for 4.1% (n=46, mostly poorly controlled pregestational diabetes), and twinning for 1.4% (n=16, conjoined or acardiac). The 79.8% (n=4390) remaining were classified as unknown etiology; of these 88.2% (n=3874) were isolated birth defects. Family history (similarly affected first degree relative) was documented in 4.8% (n=266). In this cohort, 92.1% (5067/5504) were live born infants (isolated and non-isolated birth defects): 75.3% (4147/5504) were classified as having an isolated birth defect (unknown or known etiology). Conclusions These findings underscore the gaps in our knowledge regarding the causes of birth defects. For the causes that are known, such as smoking or diabetes, assigning causation in individual cases remains challenging. Nevertheless, the ongoing impact of these exposures on fetal development highlights the urgency and benefits of population based preventive interventions. For the causes that are still unknown, better strategies are needed. These can include greater integration of the key elements of etiology, morphology, and pathogenesis into epidemiologic studies; greater collaboration between researchers (such as developmental biologists), clinicians (such as medical geneticists), and epidemiologists; and better ways to objectively measure fetal exposures (beyond maternal self reports) and closer (prenatally) to the critical period of organogenesis.
Identification of Small Molecule Translesion Synthesis Inhibitors That Target the Rev1-CT/RIR Protein−Protein Interaction

Translesion synthesis (TLS) is an important mechanism through which proliferating cells tolerate DNA damage during replication. The mutagenic Rev1/Polζ-dependent branch of TLS helps cancer cells survive first-line genotoxic chemotherapy and introduces mutations that can contribute to the acquired resistance so often observed with standard anticancer regimens. As such, inhibition of Rev1/Polζ-dependent TLS has recently emerged as a strategy to enhance the efficacy of first-line chemotherapy and reduce the acquisition of chemoresistance by decreasing tumor mutation rate. The TLS DNA polymerase Rev1 serves as an integral scaffolding protein that mediates the assembly of the active multiprotein TLS complexes. Protein–protein interactions (PPIs) between the C-terminal domain of Rev1 (Rev1-CT) and the Rev1-interacting region (RIR) of other TLS DNA polymerases play an essential role in regulating TLS activity. To probe whether disrupting the Rev1-CT/RIR PPI is a valid approach for developing a new class of targe...
Graphons: A Nonparametric Method to Model, Estimate, and Design Algorithms for Massive Networks

Many social and economic systems are naturally represented as networks, from off-line and on-line social networks, to bipartite networks, like Netflix and Amazon, between consumers and products. Graphons, developed as limits of graphs, form a natural, nonparametric method to describe and estimate large networks like Facebook and LinkedIn. Here we describe the development of the theory of graphons, for both dense and sparse networks, over the last decade. We also review theorems showing that we can consistently estimate graphons from massive networks in a wide variety of models. Finally, we show how to use graphons to estimate missing links in a sparse network, which has applications from estimating social and information networks in development economics, to rigorously and efficiently doing collaborative filtering with applications to movie recommendations in Netflix and product suggestions in Amazon.
Skip Connections Eliminate Singularities

Skip connections made the training of very deep networks possible and have become an indispensable component in a variety of neural architectures. A completely satisfactory explanation for their success remains elusive. Here, we present a novel explanation for the benefits of skip connections in training very deep networks. The difficulty of training deep networks is partly due to the singularities caused by the non-identifiability of the model. Several such singularities have been identified in previous works: (i) overlap singularities caused by the permutation symmetry of nodes in a given layer, (ii) elimination singularities corresponding to the elimination, i.e. consistent deactivation, of nodes, (iii) singularities generated by the linear dependence of the nodes. These singularities cause degenerate manifolds in the loss landscape that slow down learning. We argue that skip connections eliminate these singularities by breaking the permutation symmetry of nodes, by reducing the possibility of node elimination and by making the nodes less linearly dependent. Moreover, for typical initializations, skip connections move the network away from the "ghosts" of these singularities and sculpt the landscape around them to alleviate the learning slow-down. These hypotheses are supported by evidence from simplified models, as well as from experiments with deep networks trained on real-world datasets.
The Structural Consequences of Big Data-Driven Education

Abstract Educators and commenters who evaluate big data-driven learning environments focus on specific questions: whether automated education platforms improve learning outcomes, invade student privacy, and promote equality. This article puts aside separate unresolved—and perhaps unresolvable—issues regarding the concrete effects of specific technologies. It instead examines how big data-driven tools alter the structure of schools' pedagogical decision-making, and, in doing so, change fundamental aspects of America's education enterprise. Technological mediation and data-driven decision-making have a particularly significant impact in learning environments because the education process primarily consists of dynamic information exchange. In this overview, I highlight three significant structural shifts that accompany school reliance on data-driven instructional platforms that perform core school functions: teaching, assessment, and credentialing. First, virtual learning environments create information tech...
Pneumocystis Carinii Pneumonia and Mucosal Candidiasis in Previously Healthy Homosexual Men. Evidence of a New Acquired Cellular Immunodeficiency

Four previously healthy homosexual men contracted Pneumocystis carinii pneumonia, extensive mucosal candidiasis, and multiple viral infections. In three of the patients these infections followed prolonged fevers of unknown origin. In all four cytomegalovirus was recovered from secretions. Kaposi's sarcoma developed in one patient eight months after he presented with esophageal candidiasis. All patients were anergic and lymphopenic; they had no lymphocyte proliferative responses to soluble antigens, and their responses to phytohemagglutinin were markedly reduced. Monoclonal-antibody analysis of peripheral-blood T-cell subpopulations revealed virtual elimination of the Leu-3 / helper/inducer subset, an increased percentage of the Leu-2 + suppressor/cytoxic subset, and an increased percentage of cells bearing the thymocyte-associated antigen T10. The inversion of the T/ helper to suppressor/cytotoxic ratio suggested that cytomegalovirus infection was an important factor in the pathogenesis of the immunodeficient state. A high level of exposure of male homosexuals to cytomegalovirus-infected secretions may account for the occurrence of this immune deficiency.
A Simple and Effective Technique for Increasing Pregnancy Rates in Couples With Retrograde Ejaculation

Seven of 12 patients with retrograde ejaculation, who had at least occasional samples with reasonable sperm numbers and motility, underwent a protocol including luteinizing hormone-timed, intrauterine insemination with washed sperm recovered from the urine. Seven pregnancies have occurred to date in six patients; the one other patient is still early in the protocol period. The described technique for collecting sperm, ovulation timing, sperm recovery, and washing and intrauterine insemination are relatively simple and cost-effective and appear to be effective in contributing to pregnancies in many couples with retrograde ejaculation.