cssi/SciSciGPT-SciSciNet huggingface dataset:
Atmospheric Constraints on the Surface UV Environment of Mars at 3.9 Ga Relevant to Prebiotic Chemistry

Abstract Recent findings suggest that Mars may have been a clement environment for the emergence of life and may even have compared favorably to Earth in this regard. These findings have revived interest in the hypothesis that prebiotically important molecules or even nascent life may have formed on Mars and been transferred to Earth. UV light plays a key role in prebiotic chemistry. Characterizing the early martian surface UV environment is key to understanding how Mars compares to Earth as a venue for prebiotic chemistry. Here, we present two-stream, multilayer calculations of the UV surface radiance on Mars at 3.9 Ga to constrain the surface UV environment as a function of atmospheric state. We explore a wide range of atmospheric pressures, temperatures, and compositions that correspond to the diversity of martian atmospheric states consistent with available constraints. We include the effects of clouds and dust. We calculate dose rates to quantify the effect of different atmospheric states on UV-sensi...
Estimating Individual Treatment Effect in Observational Data Using Random Forest Methods.

Estimation of individual treatment effect in observational data is complicated due to the challenges of confounding and selection bias. A useful inferential framework to address this is the counter...
Fiscal Policy and the Firm Do Low Corporate Tax Rates Attract Multinational Corporations

The existing literature on the political economy of taxation explores how the mobility of firms affects the ability of governments to tax capital. In this article the author tests the relationship ...
Correct-by-Construction Approach for Self-Evolvable Robots

The paper presents a new formal way of modeling and designing reconfigurable robots, in which case the robots are allowed to reconfigure not only structurally but also functionally. We call such kind of robots "self-evolvable", which have the potential to be more flexible to be used in a wider range of tasks, in a wider range of environments, and with a wider range of users. To accommodate such a concept, i.e., allowing a self-evovable robot to be configured and reconfigured, we present a series of formal constructs, e.g., structural reconfigurable grammar and functional reconfigurable grammar. Furthermore, we present a correct-by-construction strategy, which, given the description of a workspace, the formula specifying a task, and a set of available modules, is capable of constructing during the design phase a robot that is guaranteed to perform the task satisfactorily. We use a planar multi-link manipulator as an example throughout the paper to demonstrate the proposed modeling and designing procedures.
Quick Sequential [Sepsis-Related] Organ Failure Assessment (qSOFA) and St. John Sepsis Surveillance Agent to Detect Patients at Risk of Sepsis: An Observational Cohort Study

The 2016 Sepsis-3 guidelines included the Quick Sequential [Sepsis-related] Organ Failure Assessment (qSOFA) tool to identify patients at risk of sepsis. The objective was to compare the utility of qSOFA to the St. John Sepsis Surveillance Agent among patients with suspected infection. The primary outcomes were in-hospital mortality or admission to the intensive care unit. A multiple center observational cohort study design was used. The study population comprised 17 044 hospitalized patients between January and March 2016. For the primary analysis, receiver operator characteristic curves were constructed for patient outcomes using qSOFA and the St. John Sepsis Surveillance Agent, and the areas under the curve were compared against a baseline risk model. Time-to-event clinical process modeling also was applied. The St. John Sepsis Surveillance Agent, when compared to qSOFA, activated earlier and was more accurate in predicting patient outcomes; in this regard, qSOFA fell far behind on both objectives.
EXPOSURE: “DO-OVERS” POSE INCREASING CHALLENGES

Obtaining adequate exposure is key to optimising outcomes in revision total knee arthroplasty. Goals of the exposure include protecting the extensor mechanism, safe removal of the components that are in place and implantation of the revision components. Challenges to these goals include prior skin incisions, arthrofibrosis, and patella baja. Choosing a skin incision is the first important step. The blood supply to the skin is predominantly derived MEDIALLY and thus the most LATERAL skin incision that works for obtaining exposure is selected. If skin flaps are required, they MUST be full thickness as the blood supply to the skin runs deep just over the fascial layer and partial thickness flaps risk skin necrosis. Avoid acute angles between old skin incisions of <60 degrees and kin bridges, if necessary must be at least 6cm in width. The work-horse of revision TKA is the medial parapatellar approach. It includes a generous medial release that allows the surgeon to externally rotate and deliver the tibia by pivoting on the extensor mechanism. An anterior synovectomy is then performed to re-establish the medial and lateral gutters followed by re-establishment of the space behind the patellar tendon to free it from the proximal tibia and finally subluxation of the patella (preferable to formal eversion). A lateral release (or peel of the soft tissue off of the lateral side of the patella) is a final step to mobilise the extensor mechanism (if required). After the components are removed, a posterior capsular release and re-establishment of the flexion space behind the femur further enhances tibial exposure for both bony preparation and revision component implantation. If the above maneuvers are performed, and exposure is still inadequate, the easiest way to improve exposure is by performing a quadriceps snip. This is an oblique, apical extension of the arthrotomy ACROSS THE PATELLAR TENDON (NOT in the muscle; it is hard to repair if performed in the muscle). It is repaired side to side with no need to alter postoperative physical therapy and heals reliably. A V-Y Quadricepsplasty is a proximal release of the extensor mechanism; essentially perform by connecting the apical extension of the medial parapatellar arthrotomy with a lateral release across the quadriceps tendon. It is classically indicated for patients with extensor mechanism contracture where the surgeon wishes to attempt lengthening the extensor mechanism. Usually results in increased flexion at the expense of an extensor lag and is used rarely in contemporary practice. Tibial Tubercle Osteotomy is a distal release of the extensor mechanism that is most useful for accessing the canal to remove long-stemmed cemented tibial components. It is a coronal osteotomy made from the medial side of the tubercle that is usually made 5–8cm in length, tapering from approximately 1cm thick proximally to 5mm distally.
Modulational Instability and Variational Structure

We study the modulational instability of periodic traveling waves for a class of Hamiltonian systems in one spatial dimension. We examine how the Jordan block structure of the associated linearized operator bifurcates for small values of the Floquet exponent to derive a criterion governing instability to long wavelengths perturbations in terms of the kinetic and potential energies, the momentum, the mass of the underlying wave, and their derivatives. The dispersion operator of the equation is allowed to be nonlocal, for which Evans function techniques may not be applicable. We illustrate the results by discussing analytically and numerically equations of Korteweg-de Vries type.
Deeply AggreVaTeD: differentiable imitation learning for sequential prediction

Recently, researchers have demonstrated state-of-the-art performance on sequential prediction problems using deep neural networks and Reinforcement Learning (RL). For some of these problems, oracles that can demonstrate good performance may be available during training, but are not used by plain RL methods. To take advantage of this extra information, we propose AggreVaTeD, an extension of the Imitation Learning (IL) approach of Ross & Bagnell (2014). AggreVaTeD allows us to use expressive differentiable policy representations such as deep networks, while leveraging training-time oracles to achieve faster and more accurate solutions with less training data. Specifically, we present two gradient procedures that can learn neural network policies for several problems, including a sequential prediction task and several high-dimensional robotics control problems. We also provide a comprehensive theoretical study of IL that demonstrates that we can expect up to exponentially-lower sample complexity for learning with AggreVaTeD than with plain RL algorithms. Our results and theory indicate that IL (and AggreVaTeD in particular) can be a more effective strategy for sequential prediction than plain RL.
Fragile X Syndrome

Fragile X syndrome causes a spectrum of problems in the emotional, cognitive, and physical domains. Our knowledge of the FMR1 gene has improved our understanding of the phenotypic spectrum in this disorder. Molecular and clinical correlations and treatment issues are reviewed here.
Memory efficient kernel approximation

Scaling kernel machines to massive data sets is a major challenge due to storage and computation issues in handling large kernel matrices, that are usually dense. Recently, many papers have suggested tackling this problem by using a low-rank approximation of the kernel matrix. In this paper, we first make the observation that the structure of shift-invariant kernels changes from low-rank to block-diagonal (without any low-rank structure) when varying the scale parameter. Based on this observation, we propose a new kernel approximation framework - Memory Efficient Kernel Approximation (MEKA), which considers both low-rank and clustering structure of the kernel matrix. We show that the resulting algorithm outperforms state-of-the-art low-rank kernel approximation methods in terms of speed, approximation error, and memory usage. As an example, on the covtype dataset with half a million samples, MEKA takes around 70 seconds and uses less than 80 MB memory on a single machine to achieve 10% relative approximation error, while standard Nystrom approximation is about 6 times slower and uses more than 400MB memory to achieve similar approximation. We also present extensive experiments on applying MEKA to speed up kernel ridge regression.
Roughness in sputtered multilayers analyzed by transmission electron microscopy and X-ray diffuse scattering

Abstract Sputtered W/C multilayers with a period of 25 A have been studied both by cross-section TEM and by X-ray diffuse scattering using 10 keV synchrotron radiation. Fitting to the X-ray data is aided by the TEM images in modeling the roughness and roughness propagation within the Born approximation. We report on a study of the correctness of the often applied small roughness approximation, and we find that is not well justified in the present case. In order to probe short lateral length scales at qy=0.1 A−1, diffuse scattering data were obtained in an unconventional scattering geometry.
Economic Effectiveness of Implementing a Statewide Building Code: The Case of Florida

Hurricane Andrew revealed inadequate construction practices were utilized in Florida for decades. In response, Florida adopted a new statewide code—the 2001 Florida Building Code (FBC)—which became one of the strictest in the nation. We use 10 years of paid insured loss data to show that the FBC reduced windstorm losses by up to 72%, then use our results to conduct a benefit-cost analysis (BCA). The FBC passes the BCA by a margin of $6 in full reduced loss to $1 of added cost, with a payback period of approximately 8 years.
Decreased Binocular Summation in Strabismic Amblyopes and Effect of Strabismus Surgery

ABSTRACTPurpose: Binocular summation (BiS) occurs when binocular visual function surpasses that of the better eye alone. We sought to evaluate whether strabismic amblyopia reduces BiS more than strabismus alone, and determine whether BiS improves in strabismic amblyopes after strabismus surgery. Methods: We prospectively recruited 15 patients with strabismic amblyopia who then underwent strabismus surgery. Thirty age-matched normal subjects and 30 non-amblyopic strabismic patients served as controls. Subjects underwent binocular and monocular visual acuity testing on high-contrast Early Treatment Diabetic Retinopathy Study (ETDRS) as well as 2.5% and 1.25% Sloan low contrast acuity (LCA) charts. BiS was calculated as the difference between better eye and binocular scores. Results: Strabismic amblyopes and strabismic controls did not significantly differ in preoperative BiS, but both had subnormal BiS preoperatively on LCA charts. Among 11 strabismic amblyopes with preoperative and postoperative BiS measur...
Issues in Trip Generation Methods for Transportation Impact Estimation of Land Use Development: A Review and Discussion of the State-of-the-Art Approaches

As agencies develop more robust planning objectives for creating sustainable and livable communities, the research community has continued developing tools for estimating transportation impacts for...
Malnutrition and the Role of Individual Variation with Evidence from India and the Philippines

SUMMARY This paper estimates the proportions of variations in the intakes of dietary energy and protein due to interindividual and intraindividual differences using four rounds of 24-hour recall data from India and the Philippines. The variances are estimated in a dynamic error components framework assuming that the number of individuals tends to infinity. It is noted that these proportions are affected by socioeconomic factors in developing countries and that the relative contribution of the within variation is likely to decline with rises in incomes. A comparison of the maximum likelihood estimates for the two countries and a breakdown of the samples by household incomes supports this hypothesis. Some implications of the results are also discussed.
Is the Rent Too High? Aggregate Implications of Local Land-Use Regulation

Highly productive U.S. cities are characterized by high housing prices, low housing stock growth, and restrictive land-use regulations (e.g., San Francisco). While new residents would benefit from housing stock growth in cities with highly productive firms, existing residents justify strict local land-use regulations on the grounds of congestion and other costs of further development. This paper assesses the welfare implications of these local regulations for income, congestion, and urban sprawl within a general-equilibrium model with endogenous regulation. In the model, households choose from locations that vary exogenously by productivity and endogenously according to local externalities of congestion and sharing. Existing residents address these externalities by voting for regulations that limit local housing density. In equilibrium, these regulations bind and house prices compensate for differences across locations. Relative to the planner's optimum, the decentralized model generates spatial misallocation whereby high-productivity locations are settled at too-low densities. The model admits a straightforward calibration based on observed population density, expenditure shares on consumption and local services, and local incomes. Welfare and output would be 1.4% and 2.1% higher, respectively, under the planner?s allocation. Abolishing zoning regulations entirely would increase GDP by 6%, but lower welfare by 5.9% because of greater congestion.
Rank Persistence: Assessing the Temporal Performance of Real-World Person Re-Identification

Designing useful person re-identification systems for real-world applications requires attention to operational aspects not typically considered in academic research. Here, we focus on the temporal aspect of re-identification; that is, instead of finding a match to a probe person of interest in a fixed candidate gallery, we consider the more realistic scenario in which the gallery is continuously populated by new candidates over a long time period. A key question of interest for an operator of such a system is: how long is a correct match to a probe likely to remain in a rank-k shortlist of candidates? We propose to distill this information into a Rank Persistence Curve (RPC), which allows different algorithms' temporal performance to be directly compared. We present examples to illustrate the RPC using a new dataset with multiple candidate reappearances, and discuss considerations for future research that explicitly involves temporal aspects.
Supplier Diversification Under Buyer Risk

When should a firm diversify its supply base? Most extant theories attribute supplier diversification to supplier risk. Herein, we develop a new theory that attributes supplier diversification to b...
Internet of Things-Based Framework to Facilitate Indoor Localization Education.

Internet of Things (IoT) is becoming a hot topic in Computer Science, especially with the advent of smart appliances such as Nest thermostats, connected light bulbs, and other IP-enabled systems. In this paper we are proposing IoT-based framework to facilitate education of indoor localization. The proposed framework employs Arduino microcontroller boards connected with XBee radio modules to perform indoor localization. The framework uses a master-slave architecture and RSSI-based triangulation to facilitate student learning of localization algorithms. Indoor localization is a field where more research is still needed, since current methods are far from perfect and have limitations in accuracy and precision. Helping students spark interest in indoor localization has the potential to bring in more young researchers into the field as well as bring in much needed new ideas.
Reexamining the “Discussion” in the Moral Dilemma Discussion

Cumulative evidence points to the effectiveness of moral dilemma discussion as a pedagogical strategy. However, much of the extant empirical research has been limited to investigating its effect on moral judgment. In addition, the potentially distinct effects of the two major components of the intervention, the intrapersonal contemplation and the interpersonal discussion that follows, have been barely examined. Using the Trolley Problem, this quasi-experimental study (N = 115) examined the effectiveness of moral dilemma discussion and of intrapersonal moral dilemma contemplation in promoting prosocial intentions among individuals in the context of a product-harm situation. The results confirm that moral dilemma discussion positively influences some forms of prosocial intentions. The results also suggest that moral dilemma discussion is not necessarily more effective than intrapersonal moral dilemma contemplation in promoting prosocial intentions.
Aeolian saltation on Mars at low wind speeds

Laboratory experiments indicate that the fluid threshold friction speed, u*tf, required to initiate fully developed aeolian saltation is much higher on Mars than on Earth. A discrepancy exists between Mars climate models that do not predict winds this strong, and observations that sand-sized particles are indeed moving. This paper describes how wind friction speeds well below u*tf, but above the impact threshold, u*ti, required to sustain saltation, can initiate sustained saltation on Mars, but at relatively low flux. Numerical experiments indicate that a sand grain on Mars mobilized sporadically between u*ti and u*tf will develop, over fetch lengths longer than generally available within low-pressure wind tunnels, trajectories capable of splashing grains that propagate saltation and collectively form a cluster of saltating grains that migrate downwind together. The passage of a saltation cluster should leave behind a narrow zone of affected surface grains. The cumulative effect of many clusters represents a low-flux phenomenon that should produce slow changes to aeolian bedforms over periods in which winds remain close to u*ti and never or rarely reach u*tf. Field evidence from small impact ripples along rover traverses is consistent with effects of saltation at these low friction speeds, without obvious evidence for events ≥ u*tf. The potential utility of this grain mobility process is that it can operate entirely at more common winds well below u*tf, and so help explain widespread sand movements observed on Mars wherever evidence might be mostly absent for u*tf being exceeded.
Investor Reaction to Covert Corporate Political Activity

Research Summary Citizens United vs. Federal Election Commission and subsequent developments created a covert channel for firms to allocate resources from corporate treasuries to political activity. Through the use of a financial market event study of an accidental disclosure of firms’ contributions to a Republican non-profit organization, I examine investors’ reactions to covert investment in independent political expenditures. I find that, on average, contributing firms experienced positive abnormal returns around the disclosure event and that these abnormal returns were more positive for firms in heavily regulated industries, as well as those previously making campaign contributions to candidates. However, firms that recently faced a shareholder resolution on political spending disclosure experienced negative abnormal returns, suggesting that the controversial nature of covert activity moderated investors’ reactions. Managerial Summary The purpose of this study is to examine how investors reacted to an accidental disclosure of firms’ investments in “dark money,” a new form of corporate political activity allowed by the U.S. Supreme Court in its Citizens United decision. I find that, on average, investors reacted positively toward firms identified as making these new political investments, especially if the firms previously engaged in electoral politics or operate in heavily regulated industries. However, this reaction turned negative if the firm recently faced a shareholder resolution asking that it voluntarily disclose all of its political investments. An implication for managers is that they should consider their firms’ legal and information environments as fully as possible before committing resources to new and potentially controversial political tactics.
The Boyce-Vest Operation for Exstrophy of the Bladder: 35 Years Later

Twenty-four patients with exstrophy of the urinary bladder (23 patients) or epispadias (1 patient) who were treated by the Boyce-Vest operation have been followed for a total of 482 patient-years (range 3 to 34 years, mean 22 years). In all patients upper urinary morphology and renal function have remained normal, and those with preoperative compromise have stabilized or improved. Postoperatively, no patient has developed an electrolyte imbalance or metabolic acidosis requiring treatment, urinary calculi, or malignant change in the vesicorectal reservoir. Although the procedure and the exstrophy-epispadias complex present many unresolved of management. The infant with exstrophy of the urinary bladder appears best served by early neonatal closure of the exstrophic bladder as described by Jeffs, 6,8 with attempts at establishing urinary continence later in childhood. 6,8,11 When other methods to establish urinary continence are unsuccessful and satisfactory anal continence has been demonstrated, the Boyce-Vest procedure offers an acceptable long-term alternative to establish sphincteric urinary continence. Properly managed, the newborn with uncomplicated exstrophy should have a life expectancy equal to that of any other neonate. More importantly, it is within our ability to provide such patients with adult social acceptability and relative freedom from urinary disease.
Planning Consequences of Traffic Systems Management

Abstract The traffic network model, TRANSYT 6, has been modified to include fuel consumption and vehicle emission impacts, as well as modal and spatial demand responses. Tests on a 5-mile section at Wilshire Boulevard in Los Angeles indicate that the most promising strategies from an environmental and passenger productivity viewpoint appear to be exclusive bus lanes and signal optimization on a passenger basis. Further tests under varying conditions are needed before traffic management guidelines can be established.
Asymptomatic Chlamydia Trachomatis Infections Among Sexually Active Men

Genital infections with Chlamydia trachomatis have been recognized as a significant public health problem in the United States. Studies of normal pregnant women have suggested that a large reservoir of asymptomatic chlamydial infection is present in poor, inner-city populations [1,2]. Among normal pregnant women, young age, out-of-wedlock conception, and multiple sexual exposures have been recognized as risk factors for endocervical infections with C. trachomatis [1-3]. Young age has also been shown to be a risk factor for C. trachomatis infection in men attending a sexually transmitted disease clinic [4]. Considerably less is known about asymptomatic infections in men in settings other than sexually transmitted disease clinics. Because men may be more likely to transmit sexually transmitted pathogens to susceptible female partners than vice versa [5], men who are unaware that they are infected are likely to play a critical role in maintaining the high prevalence of chlamydial infections in certain populations.
Spina Bifida: A New Disease

The paper by Wald entitled "Biofeedback in the Treatment of Fecal Incontinence in Patients with Myelomeningocele" (Pediatrics 68:45, 1981) represents an additional small, but significant step in the management of children with spina bifida. In the 1950s most children with spina bifida were left to die. In the 1960s most were vigorously treated. In the early 1970s Dr John Lorber presented a retrospective analysis of his results, and published his criteria for selection.1 Over these three decades the approach to the newborn with spina bifida has swung like a pendulum. More recent series2,3 demonstrate that with early treatment more than 80% of children survive; in our experience more than 95% survive.
Juvenile Punishment, High School Graduation, and Adult Crime: Evidence from Idiosyncratic Judge Harshness

This paper contributes to the debate on the impact of juvenile crime punishment on high school completion and adult recidivism using administrative data from a southern U.S. state. We exploit rando...
Model accuracy and runtime tradeoff in distributed deep learning: a systematic study

Deep learning with a large number of parameters requires distributed training, where model accuracy and runtime are two important factors to be considered. However, there has been no systematic study of the tradeoff between these two factors during the model training process. This paper presents Rudra, a parameter server based distributed computing framework tuned for training large-scale deep neural networks. Using variants of the asynchronous stochastic gradient descent algorithm we study the impact of synchronization protocol, stale gradient updates, minibatch size, learning rates, and number of learners on runtime performance and model accuracy. We introduce a new learning rate modulation strategy to counter the effect of stale gradients and propose a new synchronization protocol that can effectively bound the staleness in gradients, improve runtime performance and achieve good model accuracy. Our empirical investigation reveals a principled approach for distributed training of neural networks: the mini-batch size per learner should be reduced as more learners are added to the system to preserve the model accuracy. We validate this approach using commonly-used image classification benchmarks: CIFAR10 and ImageNet.
Survival Ambiguity and Welfare

Abstract Nearly all life-cycle models adopt Yaari’s (1965) assumption that individuals know the survival probabilities that they face. Given that an individual’s exact survival probabilities are likely unknown, we explore the implications of relaxing this assumption. If there is no annuity market, then the welfare cost of survival ambiguity is large and regressive. Ambiguity neutral individuals would pay as much as 1% of total lifetime consumption for immediate resolution of ambiguity and the bottom income quintile is 4 times worse off than the top quintile. Alternatively, with the availability of competitive annuity contracts, survival ambiguity is welfare improving because it allows competitive insurance companies to pool risk across survival types. Even though Social Security and annuities share some properties, Social Security does not help to hedge survival ambiguity.
Theoretical expectations for dark matter detection at the LHC

I present an overview of theoretical expectations for detection of dark matter (DM) at the LHC, concentrating entirely on supersymmetric candidates. En route, I present a unified theory which explains dark matter signals at indirect and direct detection experiments. While direct DM detection is likely impossible at LHC, detection of SUSY matter states is robust, where LHC with \sqrt{s}=7 TeV and 1fb^{-1} can access m(gluino) 1 TeV for m(squark) m(gluino), and m(gluino) 640 GeV for m(squark)>> m(gluino). Models with well-tempered neutralinos will soon be tested by Xenon-100/LUX, and should provide a distinctive mass edge at LHC in the m(l+l-) distribution. In the case of SUSY, neutralino dark matter now seems highly disfavored by both the magnitude of the dark matter density, and also the gravitino problem. Alternatively, the PQMSSM yields a solution to the strong CP problem, provides all the benefits of SUSY, and solves several cosmological problems. Predictions for SUSY particles at the LHC from the PQMSSM are quite different from the case of neutralino dark matter. Compelling models such as Yukawa-unifed SUSY or Effective SUSY, which would be excluded with neutralino DM, are perfectly viable with mixed axion/axino DM.
NECAPs are negative regulators of the AP2 clathrin adaptor complex

Eukaryotic cells internalize transmembrane receptors via clathrin-mediated endocytosis, but it remains unclear how the machinery underpinning this process is regulated. We recently discovered that membrane-associated muniscin proteins such as FCHo and SGIP initiate endocytosis by converting the AP2 clathrin adaptor complex to an open, active conformation that is then phosphorylated (Hollopeter et al., 2014). Here we report that loss of ncap-1, the sole C. elegans gene encoding an adaptiN Ear-binding Coat-Associated Protein (NECAP), bypasses the requirement for FCHO-1. Biochemical analyses reveal AP2 accumulates in an open, phosphorylated state in ncap-1 mutant worms, suggesting NECAPs promote the closed, inactive conformation of AP2. Consistent with this model, NECAPs preferentially bind open and phosphorylated forms of AP2 in vitro and localize with constitutively open AP2 mutants in vivo. NECAPs do not associate with phosphorylation-defective AP2 mutants, implying that phosphorylation precedes NECAP recruitment. We propose NECAPs function late in endocytosis to inactivate AP2.
Employee political affiliation as a driver of corporate social responsibility intensity

ABSTRACTThis article explores the connection between corporate social responsibility (CSR) intensity and the political affiliation of elite management and lower-level personnel and offers evidence that CSR initiatives are frequently driven from the bottom-up by employees actively expressing their sociopolitical views. While directors and CEOs play an important role within certain CSR dimensions, results suggest that employees are significantly more influential overall. A one-standard-deviation shift to the political left for directors, CEOs and elite executives yields gains in CSR of 5%, 9% and 3%, respectively, while a one-standard-deviation left-shift for employees produces a 33% increase. Findings may help to explain why similar firms engaging in comparable social initiatives can experience heterogeneous returns to CSR outlays and suggest that a corporate culture approach may be warranted in future studies.
Computation Error Analysis: Students With Mathematics Difficulty Compared To Typically Achieving Students:

Though proficiency with computation is highly emphasized in national mathematics standards, students with mathematics difficulty (MD) continue to struggle with computation. To learn more about the ...
Spontaneous dormancy protects Trypanosoma cruzi during extended drug exposure.

Chagas disease is one of the most harmful tropical diseases in the Americas. It affects millions of people, predominantly in Latin America. It is usually spread by kissing bugs infected with Trypanosoma cruzi parasites. It is considered a neglected tropical disease because few effective treatments and preventive methods are routinely used. Several drugs can kill T. cruzi parasites, but they often fail to cure the infection. Many people with Chagas disease go on to have life-long infections and eventually develop heart failure. The reason for the high rate of treatment failure is not known. It does not appear to be the result of the parasites developing resistance to the drugs. One possibility is that the parasites can hide in a dormant state in the body, dodging the toxic drugs and living to reproduce another day. Now, Sanchez-Valdez et al. identify a dormant form of the T. cruzi parasite that allows the infection to persist after treatment. In the experiments, a non-reproducing form of the so-called amastigote stage of the T. cruzi parasite inside the host cells was observed in infected mice and human cells. While some of the amastigote parasites continue multiplying, a few stop even without drug treatment – but can resume multiplication at a later time. They may also be able to change into the trypomastigote form of the parasite, which can infect new cells. These non-multiplying amastigotes can survive drug treatment for as long as 30 days, whereas the multiplying amastigotes are killed by such drugs. However, the surviving amastigotes then reestablish active infections after treatment has stopped. The experiments explain why treatment so often fails to cure Chagas disease. This suggests new treatment strategies are needed, including using existing drugs for a longer time perhaps with less frequent doses. New therapies that kill the dormant amastigotes may also help. Treatments that overcome the parasite’s ability to hide, could stop the progression of the disease and prevent heart-related deaths in those with persistent T. cruzi infections.
Pseudorandom Generators for Low Sensitivity Functions

A Boolean function is said to have maximal sensitivity s if s is the largest number of Hamming neighbors of a point which differ from it in function value. We initiate the study of pseudorandom generators fooling low-sensitivity functions as an intermediate step towards settling the sensitivity conjecture. We construct a pseudorandom generator with seed-length 2^{O(s^{1/2})} log(n) that fools Boolean functions on n variables with maximal sensitivity at most s. Prior to our work, the (implicitly) best pseudorandom generators for this class of functions required seed-length 2^{O(s)} log(n).
Computational Materials Science, an Increasingly Reliable Engineering Tool: Anomalous Nitride Band Structures and Device Consequences

Computational materials science has evolved in recent years into a reliable theory capable of predicting not only idealized materials and device performance properties, but also those that apply to practical engineering developments. The codes run on workstations and even now are fast enough to be useful design tools. A review will be presented of the current status of this rapidly advancing field. Examples of the accuracy of the codes are displayed by comparing the predicted atomic volumes, and cohesive and excess energies of several materials with experiment. As a further demonstration of the methods, the band structures of AlN, GaN, and InN in wurtzite and zinc blende structures will be presented. There are anomalies in the conduction and valence bands of these materials. Some consequences on light emitting and power devices made from these materials will be examined.
Analysis of motility in multicellular Chlamydomonas reinhardtii evolved under predation

The advent of multicellularity was a watershed event in the history of life, yet the transition from unicellularity to multicellularity is not well understood. Multicellularity opens up opportunities for innovations in intercellular communication, cooperation, and specialization, which can provide selective advantages under certain ecological conditions. The unicellular alga Chlamydomonas reinhardtii has never had a multicellular ancestor yet it is closely related to the volvocine algae, a clade containing taxa that range from simple unicells to large, specialized multicellular colonies. Simple multicellular structures have been observed to evolve in C. reinhardtii in response to predation or to settling rate-based selection. Structures formed in response to predation consist of individual cells confined within a shared transparent extracellular matrix. Evolved isolates form such structures obligately under culture conditions in which their wild type ancestors do not, indicating that newly-evolved multicellularity is heritable. C. reinhardtii is capable of photosynthesis, and possesses an eyespot and two flagella with which it moves towards or away from light in order to optimize input of radiant energy. Motility contributes to C. reinhardtii fitness because it allows cells or colonies to achieve this optimum. Utilizing phototaxis to assay motility, we determined that newly evolved multicellular strains do not exhibit significant directional movement, even though the flagellae of their constituent unicells are present and active. In C. reinhardtii the first steps towards multicellularity in response to predation appear to result in a trade-off between motility and differential survivorship, a trade-off that must be overcome by further genetic change to ensure long-term success of the new multicellular organism.
The Persistent Effect of Pre-College Computing Experience on College CS Course Grades

Many college computer science majors have little or no pre-college computing experience. Previous work has shown that inexperienced students under-perform their experienced peers when placed in the same introductory courses, and are more likely to drop out of the CS program. However, not much is known about what, if any, differences may persist beyond the introductory sequence for students who remain in the program. We conducted a study across all levels of a CS program at a large public university in the United States to determine whether grade differences exist between students with and without pre-college experience, and if so, for what types of experiences. We find significant grade differences in courses at all levels of the program. We further find that students who took AP Computer Science receive significantly higher average grades---by up to a half grade---in nearly all courses we studied. Pre-college experience appears to have a weaker relationship with retention and with low-stakes assessment grades. We discuss the limitations of these findings and implications for high school and college level CS courses and programs.
Beyond Markov: Accounting for independence violations in causal reasoning.

Abstract Although many theories of causal cognition are based on causal graphical models, a key property of such models—the independence relations stipulated by the Markov condition—is routinely violated by human reasoners. This article presents three new accounts of those independence violations, accounts that share the assumption that people’s understanding of the correlational structure of data generated from a causal graph differs from that stipulated by causal graphical model framework. To distinguish these models, experiments assessed how people reason with causal graphs that are larger than those tested in previous studies. A traditional common cause network ( Y 1 ← X → Y 2 ) was extended so that the effects themselves had effects ( Z 1 ← Y 1 ← X → Y 2 → Z 2 ). A traditional common effect network ( Y 1 → X ← Y 2 ) was extended so that the causes themselves had causes ( Z 1 → Y 1 → X ← Y 2 ← Z 2 ). Subjects’ inferences were most consistent with the beta-Q model in which consistent states of the world—those in which variables are either mostly all present or mostly all absent—are viewed as more probable than stipulated by the causal graphical model framework. Substantial variability in subjects’ inferences was also observed, with the result that substantial minorities of subjects were best fit by one of the other models (the dual prototype or a leaky gate models). The discrepancy between normative and human causal cognition stipulated by these models is foundational in the sense that they locate the error not in people’s causal reasoning but rather in their causal representations. As a result, they are applicable to any cognitive theory grounded in causal graphical models, including theories of analogy, learning, explanation, categorization, decision-making, and counterfactual reasoning. Preliminary evidence that independence violations indeed generalize to other judgment types is presented.
Sub-Nano-Tesla, Shield-Less, Field Compensation-Free Inelastic Wave Mixing Magnetometry for Bio-Magnetism

We report an inelastic-wave-mixing-enhanced Zeeman-coherence atomic magnetometry scheme that results in sub-nT magnetic field detection at human-body temperatures without employing magnetic field shielding, field compensation, and RF-modulation spectroscopy.
Concept of quantum timing jitter and non-Markovian limits in single photon detection

We propose the concept of quantum timing jitter in single-photon detection, based on the observation of a finite rise time in the quantum probabilistic signal transduction (absorption). We place a fundamental limit on this quantum jitter, which is governed by the bandwidth of the field-detector interaction spectrum. We also shed light on the fundamental differences between linear and nonlinear detector outputs for single photon Fock state vs. coherent state pulses.
Ohm's law for mean magnetic fields

The magnetic fields associated with plasmas frequently exhibit small-amplitude MHD fluctuations. It is useful to have equations for the magnetic field averaged over these fluctuations, the so-called mean field equations. Under very general assumptions, it is shown that the effect of MHD fluctuations on a force-free plasma can be represented by one parameter in Ohm's law, which is effectively the coefficient of electric current viscosity.
Detection of Paroxysmal Atrial Fibrillation using Attention-based Bidirectional Recurrent Neural Networks

Detection of atrial fibrillation (AF), a type of cardiac arrhythmia, is difficult since many cases of AF are usually clinically silent and undiagnosed. In particular paroxysmal AF is a form of AF that occurs occasionally, and has a higher probability of being undetected. In this work, we present an attention based deep learning framework for detection of paroxysmal AF episodes from a sequence of windows. Time-frequency representation of 30 seconds recording windows, over a 10 minute data segment, are fed sequentially into a deep convolutional neural network for image-based feature extraction, which are then presented to a bidirectional recurrent neural network with an attention layer for AF detection. To demonstrate the effectiveness of the proposed framework for transient AF detection, we use a database of 24 hour Holter Electrocardiogram (ECG) recordings acquired from 2850 patients at the University of Virginia heart station. The algorithm achieves an AUC of 0.94 on the testing set, which exceeds the performance of baseline models. We also demonstrate the cross-domain generalizablity of the approach by adapting the learned model parameters from one recording modality (ECG) to another (photoplethysmogram) with improved AF detection performance. The proposed high accuracy, low false alarm algorithm for detecting paroxysmal AF has potential applications in long-term monitoring using wearable sensors.
Graph Oracle Models, Lower Bounds, and Gaps for Parallel Stochastic Optimization

We suggest a general oracle-based framework that captures parallel stochastic optimization in different parallelization settings described by a dependency graph, and derive generic lower bounds in terms of this graph. We then use the framework and derive lower bounds to study several specific parallel optimization settings, including delayed updates and parallel processing with intermittent communication. We highlight gaps between lower and upper bounds on the oracle complexity, and cases where the ``natural'' algorithms are not known to be optimal.
Revisiting short-term earthquake triggered volcanism

It has been noted for centuries that earthquakes appear to trigger the eruption of volcanoes. For example, analyses of global volcanic and seismic records since 1500 AD have shown that explosive eruptions with Volcanic Explosivity Index (VEI) values ≥2 are preceded within days by nearby major earthquakes (magnitude M8 or larger) about 4 times more often than expected due to coincidence, suggesting that large earthquakes can trigger eruptions. We expand the definition of a triggered eruption to include the possibility of M6 or greater earthquakes within 5 days and 800 km of a VEI 2 or greater eruption. Removing pre-1964 records, to ensure complete and accurate catalogs, we find 30 volcanoes that at some point experienced a potentially triggered eruption and define these volcanoes as “sensitive” volcanoes. Within this group of sensitive volcanoes, normalized distributions of volcano-centric factors such as tectonic setting, dominant rock type, and type of volcano are practically indistinguishable from those of sensitive volcanoes in which the time of eruption is randomized. Comparisons of sensitive volcanoes and insensitive volcanoes (i.e., volcanoes that have never experienced a triggered eruption) reveal that sensitive volcanoes are simply more active than insensitive volcanoes: They erupt more frequently, are located solely in subduction zones, and erupt primarily andesites and basaltic-andesites. The potentially triggered eruptions do not show the magnitude-distance relationship expected for seismically induced responses (e.g., hydrologic responses), and eruptions that do occur within days of nearby earthquakes do so within rates expected by random chance. There is, however, a 5–12% increase in the number of explosive eruptions in the 2 months to 2 years following major earthquakes. We conclude that short-term seismically triggered explosive eruptions occur less frequently than previously inferred, an important conclusion when considering volcanic hazards and for understanding the nature of earthquake-volcano interactions.
Genetic and environmental contributions to the association between violent victimization and major depressive disorder

Abstract Research suggests victims of violent crime are more likely to suffer from major depressive disorder (MDD) compared to non-victims. Less research has utilized longitudinal data to evaluate the directionality of this relationship or examined the genetic and environmental contributions to this association across the life course. The current study evaluated 473 full-sibling pairs and 209 half-sibling pairs (N = 1364) from the National Longitudinal Survey of Youth (Mage = 20.14, SD = 3.94). Cross-lagged models were used to examine the directionality of effects between violent victimization and MDD over time. Biometric liability models were used to examine genetic and environmental influences on single and chronic violent victimization and MDD. Violent victimization was associated with increases in MDD during late adolescence, but MDD was more associated with increased risk for violent victimization across young adulthood. Biometric analysis indicated that 20% and 30% of the association between MDD and single and chronic victimization, respectively, was accounted for by common genetic influences. Results from the current study suggest individuals who exhibit symptoms of MDD may be at higher risk for chronic victimization rather than developing MDD as a result of victimization.