cssi/SciSciGPT-SciSciNet huggingface dataset:
A Dirichlet process mixture model for clustering longitudinal gene expression data

Subgroup identification (clustering) is an important problem in biomedical research. Gene expression profiles are commonly utilized to define subgroups. Longitudinal gene expression profiles might provide additional information on disease progression than what is captured by baseline profiles alone. Therefore, subgroup identification could be more accurate and effective with the aid of longitudinal gene expression data. However, existing statistical methods are unable to fully utilize these data for patient clustering. In this article, we introduce a novel clustering method in the Bayesian setting based on longitudinal gene expression profiles. This method, called BClustLonG, adopts a linear mixed-effects framework to model the trajectory of genes over time, while clustering is jointly conducted based on the regression coefficients obtained from all genes. In order to account for the correlations among genes and alleviate the high dimensionality challenges, we adopt a factor analysis model for the regression coefficients. The Dirichlet process prior distribution is utilized for the means of the regression coefficients to induce clustering. Through extensive simulation studies, we show that BClustLonG has improved performance over other clustering methods. When applied to a dataset of severely injured (burn or trauma) patients, our model is able to identify interesting subgroups. Copyright © 2017 John Wiley & Sons, Ltd.
Modular multitask reinforcement learning with policy sketches

We describe a framework for multitask deep reinforcement learning guided by policy sketches. Sketches annotate tasks with sequences of named subtasks, providing information about high-level structural relationships among tasks but not how to implement them—specifically not providing the detailed guidance used by much previous work on learning policy abstractions for RL (e.g. intermediate rewards, subtask completion signals, or intrinsic motivations). To learn from sketches, we present a model that associates every subtask with a modular subpolicy, and jointly maximizes reward over full task-specific policies by tying parameters across shared subpolicies. Optimization is accomplished via a decoupled actor-critic training objective that facilitates learning common behaviors from multiple dissimilar reward functions. We evaluate the effectiveness of our approach in three environments featuring both discrete and continuous control, and with sparse rewards that can be obtained only after completing a number of high-level sub-goals. Experiments show that using our approach to learn policies guided by sketches gives better performance than existing techniques for learning task-specific or shared policies, while naturally inducing a library of interpretable primitive behaviors that can be recombined to rapidly adapt to new tasks.
Modular knowledge systems accelerate human migration in asymmetric random environments.

Migration is a key mechanism for expansion of communities. In spatially heterogeneous environments, rapidly gaining knowledge about the local environment is key to the evolutionary success of a migrating population. For historical human migration, environmental heterogeneity was naturally asymmetric in the north–south (NS) and east–west (EW) directions. We here consider the human migration process in the Americas, modelled as random, asymmetric, modularly correlated environments. Knowledge about the environments determines the fitness of each individual. We present a phase diagram for asymmetry of migration as a function of carrying capacity and fitness threshold. We find that the speed of migration is proportional to the inverse complement of the spatial environmental gradient, and in particular, we find that NS migration rates are lower than EW migration rates when the environmental gradient is higher in the NS direction. Communication of knowledge between individuals can help to spread beneficial knowledge within the population. The speed of migration increases when communication transmits pieces of knowledge that contribute in a modular way to the fitness of individuals. The results for the dependence of migration rate on asymmetry and modularity are consistent with existing archaeological observations. The results for asymmetry of genetic divergence are consistent with patterns of human gene flow.
Deformable kernels for early vision

Early vision algorithms often have a first stage of linear-filtering that 'extracts' from the image information at multiple scales of resolution and multiple orientations. A common difficulty in the design and implementation of such schemes is that one feels compelled to discretize coarsely the space of scales and orientations in order to reduce computation and storage costs. A technique is presented that allows: 1) computing the best approximation of a given family using linear combinations of a small number of 'basis' functions; and 2) describing all finite-dimensional families, i.e., the families of filters for which a finite dimensional representation is possible with no error. The technique is based on singular value decomposition and may be applied to generating filters in arbitrary dimensions and subject to arbitrary deformations. The relevant functional analysis results are reviewed and precise conditions for the decomposition to be feasible are stated. Experimental results are presented that demonstrate the applicability of the technique to generating multiorientation multi-scale 2D edge-detection kernels. The implementation issues are also discussed. >
Flight-Test Techniques for Quantifying Pitch Rate and Angle-of-Attack Rate Dependencies

Three different types of maneuvers were designed to separately quantify the pitch rate and angle-of-attack rate contributions to the nondimensional aerodynamic pitching moment coefficient. These maneuvers combined pilot inputs and automatic multisine excitations, and they were demonstrated with the subscale T-2 and Bat-4 airplanes using the NASA Airborne Subscale Transport Aircraft Research flight-test facility. Stability and control derivatives (in particular, Cmq and Cmα˙) were accurately estimated from the flight-test data. These maneuvers can be performed with many types of aircraft, and the results can be used to improve physical insight into the flight dynamics, facilitate more accurate comparisons with wind-tunnel experiments or numerical investigations, and increase simulation prediction fidelity.
Firm Dynamics, Persistent Effects of Entry Conditions, and Business Cycles

This paper examines how the state of the economy when businesses begin operations affects their size and performance over the lifecycle. Using micro-level data that covers the entire universe of businesses operating in the U.S. since the late 1970s, I provide new evidence that businesses born in downturns start on a smaller scale and remain smaller over their entire lifecycle. In fact, I find no evidence that these differences attenuate even long after entry. Using new data on the productivity and composition of startup businesses, I show that this persistence is related to selection at entry and demand-side channels.
Information asymmetries and identification bias in P2P social microlending

The Internet has created new opportunities for peer-to-peer P2P social lending platforms, which have the potential to transform the way microfinance institutions raise and allocate funds used for poverty reduction. Depending upon where decision-making rights are allocated, there is the potential for identification bias whereby lenders may be motivated to give to specific projects with which they have an affinity without regard to whether it represents a sound financial investment. Using data collected from Kiva, we present empirical evidence that distant upstream lenders do not have adequate information about local business and loan conditions to make sound microfinance funding decisions, but instead make decisions based on identification biases. Furthermore, more information provided on the P2P lending site about the prospective loan does not improve the lender’s information about the loan conditions, but rather exacerbates the identification bias effect.
State-Space Adaptation of Unsteady Lifting Line Theory: Twisting/Flapping Wings of Finite Span

In this paper, a low-order state-space adaptation of the unsteady lifting line model has been analytically derived for a wing of finite aspect ratio, suitable for use in real-time control of wake-d...
50 years of radio-scintillation observations

The author attempts a brief summary of the history of ionospheric fading from sources beyond the upper atmosphere. The concentration is on the early studies of scintillation. The first sources used as transmitters were radio stars with varying diameters. With the advent of satellite transmissions at altitudes varying from 300 km to several Earth radii, fading was studied as a function of various regions of the globe. In years of high solar flux, transionospheric propagation through polar and equatorial regions has experience deep fading at frequencies ranging from 54 MHz to 4 GHz. Fading of radio signals from satellites still plays a role in evaluating operational and proposed system effectiveness. The relevance of these studies to Global Positioning System reception and users of proposed systems at L band is discussed.
Structure-preserving second-order integration of relativistic charged particle trajectories in electromagnetic fields

Time-centered, hence second-order, methods for integrating the relativistic momentum of charged particles in an electromagnetic field are derived. A new method is found by averaging the momentum before use in the magnetic rotation term, and an implementation is presented that differs from the relativistic Boris Push only in the method for calculating the Lorentz factor. This is shown to have the same second-order accuracy in time as that found by splitting the electric acceleration and magnetic rotation (Boris Push) and that found by averaging the velocity in the magnetic rotation term (Vay's method) [J.-L. Vay, Phys. Plasmas 15, 056701 (2008)]. All three methods are shown to conserve energy when there is no electric field. The Boris Push and the current method are shown to be volume-preserving, while Vay's method and the current method preserve the E→×B→ velocity. Thus, of these second-order relativistic momentum integrations, only the integrator introduced here both preserves volume and gives the correc...
Colour asymmetry between galaxies with clockwise and counterclockwise handedness

Recent studies have shown that SDSS galaxies with clockwise patterns are photometrically different from galaxies with anti-clockwise patterns. The purpose of this study is to identify possible differences between the colour of galaxies with clockwise handedness and the colour of galaxies with anti-clockwise handedness. A dataset of 162,514 SDSS galaxies was separated into clockwise and counterclockwise galaxies, and the colours of spiral galaxies with clockwise handedness were compared to the colour of spiral galaxies with anti-clockwise handedness. The results show that the i-r colour in clockwise galaxies in SDSS is significantly higher compared to anti-clockwise SDSS galaxies. The colour difference is strongest between the right ascension of 30° and 60°, while the RA range of 180° to 210° shows a much smaller difference. Similarly, comparing other photometric measurements in clockwise and anti-clockwise galaxies exhibit statistically significant difference, showing the SDSS pipeline is sensitive to the handedness of the galaxy.
Investment Terms and Level of Control of China’s Sovereign Wealth Fund in its Portfolio Firms

Based on a hand-collected dataset consisting of 61 MA and it is a rule rather than exception that CIC is generally not represented in targets’ boards. Except for one Chinese company in which CIC is the second largest shareholder, there is no evidence of CIC pursuing shareholder activism by exercising its voting rights or bringing up proposals, neither in shareholder or board meetings of the portfolio companies. Although CIC does not seem to have actively exercised much of its formal control mechanisms in its investments especially when compared to its wholly-owned subsidiary Huijin, such contrast is arguably resulted more from the practical infeasibility of doing so in minority overseas equity holdings, than from the prepared deviation of CIC from its “strategic governmental investor” role. This being said, given the practical concern of the target firms that they cannot easily afford losing such an important investor and business partner, there are still plenty of opportunities that CIC could extract indirect private control benefits from them in the long-term post-investment relationships. Combined, these findings show that, forcing SWFs to remain passive in the corporate governance realm by, for example, asking them to suspend their voting rights may not be entirely needed or helpful. Rather, the regulators of countries hosting SWF investments should carefully consider the necessity and level of any proposed regulation directed at SWFs as a particular type of investors, which should be weighed against the volume, performance and effect of the investments in the first place.
A broadband 10-GHz track-and-hold in Si/SiGe HBT technology

High-performance multistage data converters and sub-sampling frequency downconverters typically require track and hold amplifiers (THAs) with high sampling rates and high linearity. This paper presents a THA for sub-sampling communications applications based on a diode bridge design with high-speed Schottky diodes and an improved current source approach for enhanced linearity. Implemented in a 45-GHz BiCMOS Si/SiGe process, this IC has an input bandwidth in excess of 10 GHz, consumes approximately 550 mW, and can accommodate input voltages up to 600 mV. With an input frequency of 8.05 GHz and a sampling frequency of 4 GHz, the THA has an IIP3 of 26 dBm and a spurious free dynamic range of 30 dB.
Chronic Embolic Pulmonary Hypertension Caused by Pulmonary Embolism and Vascular Endothelial Growth Factor Inhibition.

Our understanding of the pathophysiological basis of chronic thromboembolic pulmonary hypertension (CTEPH) will be accelerated by an animal model that replicates the phenotype of human CTEPH. Sprague-Dawley rats were administered a combination of a single dose each of plastic microspheres and vascular endothelial growth factor receptor antagonist in polystyrene microspheres (PE) + tyrosine kinase inhibitor SU5416 (SU) group. Shams received volume-matched saline; PE and SU groups received only microspheres or SU5416, respectively. PE + SU rats exhibited sustained pulmonary hypertension (62 ± 13 and 53 ± 14 mmHg at 3 and 6 weeks, respectively) with reduction of the ventriculoarterial coupling in vivo coincident with a large decrement in peak rate of oxygen consumption during aerobic exercise, respectively. PE + SU produced right ventricular hypokinesis, dilation, and hypertrophy observed on echocardiography, and 40% reduction in right ventricular contractile function in isolated perfused hearts. High-resolution computed tomographic pulmonary angiography and Ki-67 immunohistochemistry revealed abundant lung neovascularization and cellular proliferation in PE that was distinctly absent in the PE + SU group. We present a novel rodent model to reproduce much of the known phenotype of CTEPH, including the pivotal pathophysiological role of impaired vascular endothelial growth factor–dependent vascular remodeling. This model may reveal a better pathophysiological understanding of how PE transitions to CTEPH in human treatments.
Curious partner: An approach to realize common ground in human-autonomy collaboration

A dialog-based human-autonomy interaction ap- proach, called curious partner, is presented for a class of systems where the role of autonomy is to assist humans in decision making tasks. Even if the human and the autonomy share the environment and receive identical information, they may have inconsistencies in the representation of the environment due to difference in their perception and expert knowledge. The curious partner interaction framework is presented to resolve model-level differences between the human and the autonomy to establish common ground. The knowledge base of the autonomy is modeled using a Bayesian engine. The autonomy's dialog with the human acts as a feedback mechanism to resolve any differences either by suggesting maximally probable actions to human based on the state of its Bayesian model or by updating its model to achieve analogous world representation.
Eccentric gravitational wave bursts in the post-Newtonian formalism

The detection of GW150914 by ground based gravitational wave observatories has brought about a new era in astrophysics. At optimal sensitivity, these observatories are expected to detect several events each year, with one or two of these occurring with non-negligible eccentricity. Such eccentric binaries will emit bursts of gravitational radiation during every pericenter passage, where orbital velocities can reach greater than ten percent the speed of light. As a result, such binaries may prove to be powerful probes of extreme gravitational physics and astrophysics. A promising method of achieving detection of such binaries is through power stacking, where the power in each burst is added up in time-frequency space. This detection strategy requires a theoretical prior of where the bursts will occur in time and frequency so that one knows where to search for successive bursts. We here present a generic post-Newtonian formalism for constructing such time-frequency model priors at generic post-Newtonian order. We apply our formalism to generate a burst model at third post-Newtonian order, making it potentially the most accurate, fully analytic model to date.
An online optimization approach for multi-agent tracking of dynamic parameters in the presence of adversarial noise

This paper addresses tracking of a moving target in a multi-agent network. The target follows a linear dynamics corrupted by an adversarial noise, i.e., the noise is not generated from a statistical distribution. The location of the target at each time induces a global time-varying loss function, and the global loss is a sum of local losses, each of which is associated to one agent. Agents noisy observations could be nonlinear. We formulate this problem as a distributed online optimization where agents communicate with each other to track the minimizer of the global loss. We then propose a decentralized version of the Mirror Descent algorithm and provide the non-asymptotic analysis of the problem. Using the notion of dynamic regret, we measure the performance of our algorithm versus its offline counterpart in the centralized setting. We prove that the bound on dynamic regret scales inversely in the network spectral gap, and it represents the adversarial noise causing deviation with respect to the linear dynamics. Our result subsumes a number of results in the distributed optimization literature. Finally, in a numerical experiment, we verify that our algorithm can be simply implemented for multi-agent tracking with nonlinear observations.
Suspended Carbon Nanotube Quantum Wires with Two Gates

Suspended single-walled carbon nanotube devices comprised of high-quality electrical contacts and two electrostatic gates per device have been prepared. Compared to nanotubes pinned on substrates, the suspended devices exhibit little hysteresis related to environmental factors and act as cleaner Fabry-Perot interferometers or single-electron transistors. The high-field saturation currents in the suspended nanotubes related to optical phonon or zone-boundary phonon scattering are significantly lower due to the lack of efficient heat sinking. The multiple-gate design may also facilitate future investigations into the electromechanical properties of nanotube quantum systems.
A simplification of Morita's construction of total right rings of quotients for a class of rings

The total right ring of quotients Qtotr(R), sometimes also called the maximal flat epimorphic right ring of quotients or right flat epimorphic hull, is usually obtained as a directed union of a certain family of extension of the base ring R. In [K. Morita, Flat modules, injective modules and quotient rings, Math. Z. 120 (1971) 25–40], Qtotr(R) is constructed in a different way, by transfinite induction on ordinals. Starting with the maximal right ring of quotients Qmaxr(R), its subrings are constructed until Qtotr(R) is obtained. Here, we prove that Morita's construction of Qtotr(R) can be simplified for rings satisfying condition (C) that every subring of the maximal right ring of quotients Qmaxr(R) containing R is flat as a left R-module. We illustrate the usefulness of this simplification by considering the class of right semihereditary rings all of which satisfy condition (C). We prove that the construction stops after just one step and we obtain a simple description of Qtotr(R) in this case. Lastly, we study conditions that imply that Morita's construction ends in countably many steps.
Corporate advantage in customer-centric diversification

AbstractOur theory explains how multi-product corporations that engage in customer-centric diversification can create and sustain corporate advantage. First, we invoke the concept of customer-centric assets to explain their role as the cornerstone of corporate advantage in customer-centric diversification. Second, our explanation of the corporate advantage in customer-centric diversification goes beyond the hypothetical ‘consumer synergies’ argument to also include the ‘market-power advantage’ argument. We explain the mechanisms employed by multi-product firms to share and/or leverage their customer-centric assets to create corporate advantage. Third, we explain how sustaining the corporate advantage so achieved requires the organizational-renewal activities to go beyond simply addressing the changing nature of the firm’s demand-side resource (i.e. customer-base) to manage revenue and/or profits.
A Magnetohydrodynamic Boost for Relativistic Jets

We have performed relativistic magnetohydrodynamic simulations of the hydrodynamic boosting mechanism for relativistic jets explored by Aloy & Rezzolla (2006) using the RAISHIN code. Simulation results show that the presence of a magnetic field may change the properties of the shock interface between the tenuous, overpressured jet (V(sub j) (sup z)) flowing tangentially to a dense external medium. Magnetic fields can lead to more efficient acceleration of the jet, in comparison to the pure-hydrodynamic case. A poloidal magnetic field (B(sup z)), tangent to the interface and parallel to the jet flow, produces both a stronger outward moving shock and inward moving rarefaction wave. This leads to a large velocity component normal to the interface in addition to acceleration tangent to the interface, and the jet is thus accelerated to a larger Lorentz factors than those obtained in the pure-hydrodynamic case. In contrast, a strong toroidal magnetic field (B(sup y)), tangent to the interface but perpendicular to the jet flow, also leads to stronger acceleration tangent to the shock interface relative to the pure-hydrodynamic case, but to a lesser extent than found for the poloidal case due to the fact that the velocity component normal to the shock interface is now much smaller. Overall, the acceleration efficiency in the toroidal case is less than that of the poloidal case but both geometries still result in higher Lorentz factors than the pure-hydrodynamic case. Thus, the presence and relative orientation of a magnetic field in relativistic jets can have a significant influence on the hydrodynamic boost mechanism studied by Aloy & Rezzolla (2006).
Soft-gluon corrections to hard-scattering cross sections through NNNLO

I present a systematic approach to calculating soft-gluon corrections through next-to-next-to-nextto-leading order for arbitrary hard-scattering cross sections. Using a unified approach, master formulas are derived for processes with both simple and complex color flows. Applications and numerical results are given for some processes of interest, including charged Higgs production and top quark production in the Standard Model and beyond.
Overall survival benefit associated with adjuvant radiotherapy in WHO grade II meningioma.

Background Adjuvant radiotherapy (RT) after surgical resection of World Health Organization (WHO) grade II meningioma, also known as atypical meningioma (AM), is a topic of controversy. The purpose of this study is to compare overall survival (OS) with or without adjuvant RT after subtotal resection (STR) or gross total resection (GTR) in AM patients diagnosed according to the 2007 WHO classification. Methods The National Cancer Database was used to identify 2515 patients who were diagnosed with AM between 2009 and 2012 and underwent STR or GTR with or without adjuvant RT. Propensity score matching was first applied to balance covariates including age, year of diagnosis, sex, race, histology, and tumor size in STR or GTR cohorts stratified by adjuvant RT status. Multivariate regression according to the Cox proportional hazards model and Kaplan-Meier survival plots with log-rank test were then used to evaluate OS difference associated with adjuvant RT. Results GTR is associated with improved OS compared with STR. In the subgroup analysis, adjuvant RT in patients who underwent STR demonstrated significant association with improved OS compared with no adjuvant RT (adjusted hazard ratio [AHR] 0.590, P = .045); however, adjuvant RT is not associated with improved OS in patients who underwent GTR (AHR 1.093, P = .737). Conclusions Despite the lack of consensus on whether adjuvant RT reduces recurrence after surgical resection of AM, our study observed significantly improved OS with adjuvant RT compared with no adjuvant RT after STR.
Oxygen migration during resistance switching and failure of hafnium oxide memristors

While the recent establishment of the role of thermophoresis/diffusion-driven oxygen migration during resistance switching in metal oxide memristors provided critical insights required for memristor modeling, extended investigations of the role of oxygen migration during ageing and failure remain to be detailed. Such detailing will enable failure-tolerant design, which can lead to enhanced performance of memristor-based next-generation storage-class memory. Here, we directly observed lateral oxygen migration using in-situ synchrotron x-ray absorption spectromicroscopy of HfOx memristors during initial resistance switching, wear over millions of switching cycles, and eventual failure, through which we determined potential physical causes of failure. Using this information, we reengineered devices to mitigate three failure mechanisms and demonstrated an improvement in endurance of about three orders of magnitude.
NATURAL TIBIOFEMORAL AND PATELLOFEMORAL KINEMATICS OF THE KNEE IN OLDER ADULTS DURING ACTIVITIES OF DAILY LIVING

Introduction Accurate measurement of knee motion is necessary for assessment of natural joint function and in the diagnosis of pathology. In particular, precise knowledge of natural knee mechanics provides useful metrics for comparison to knee function following total knee arthroplasty (TKA). Reported measurements of natural knee kinematics during activities of daily living are rare, and often do not include both tibiofemoral (TF) and patellofemoral (PF) articulations. What's more, most studies record knee motion of younger subjects that are not necessarily representative of the age range associated with degenerative changes and TKA. The purpose of this study was to measure TF and PF kinematics of healthy older adults as they performed activities of daily living, including tasks considered more demanding for the knee [1]. Methods High speed stereo radiography (HSSR) was used to measure the kinematics of the PF and TF joints. HSSR utilizes two views of the knee to capture 3D sub-mm measurements accurate to within ±0.15 mm in translation and ±0.41° in rotation [2]. Eight healthy subjects (4M/4F, 64.4±8.2 years, BMI: 27.6±4.8 kg/m2) performed six activities of daily living: seated knee extension, lunge, chair rise, gait, pivot and step down (Figure 1). The 3D geometry of the femur, tibia, and patella of each subject was reconstructed from CT and used to track bone motions using Autoscoper (Brown University, Providence RI). Motion of the tibia and patella were reported relative to a coordinate system centered in the posterior condyles of the femur [3]. Average range of motion (ROM) for each DOF was calculated as the difference between the maximum and the minimum value and averaged across the subjects for each activity. Results and Discussion Average patella ROM during the lunge and chair-rise activities was within the ROM of the knee extension, demonstrating consistent tracking of the patella during the loaded deep flexion activities. Tibia motion relative to the femur was consistent in trend during the knee extension, lunge, and chair rise, with the exceptions of increased internal rotation and anterior translation during weight bearing (Figure 2a). In agreement with in vitro studies [4], tibial and patellar internal rotation increased with knee flexion consistently across the high knee flexion activities (Figure 2a). Tibial and patellar external rotation increased as the subjects approached heel-off as they executed a pivot (Figure 3a). Higher-demand tasks, pivot and step down, presented larger ROM than gait with notable increase in tibial external rotation and patellar flexion, respectively (Figure 3b). The decreasing congruence of the patella and trochlea as the knee extends likely explains the greater variability in patella ROM in gait, pivot, and step down activities [5]. In conclusion, evaluating natural kinematics of the tibia and patella and their interaction during a variety of activities of daily living provides a standard for the evaluation of knee pathology and treatment.
Evolving Ext4 for shingled disks

Drive-Managed SMR (Shingled Magnetic Recording) disks offer a plug-compatible higher-capacity replacement for conventional disks. For non-sequential workloads, these disks show bimodal behavior: After a short period of high throughput they enter a continuous period of low throughput. We introduce ext4-lazy, a small change to the Linux ext4 file system that significantly improves the throughput in both modes. We present benchmarks on four different drive-managed SMR disks from two vendors, showing that ext4-lazy achieves 1.7-5.4× improvement over ext4 on a metadata-light file server benchmark. On metadata-heavy benchmarks it achieves 2-13× improvement over ext4 on drive-managed SMR disks as well as on conventional disks.
Why are REITS Currently So Expensive

Over the last several years, the price of listed real estate stocks has been unusually high relative to dividends. I find that neither low interest rates nor low risk premia can account for the high valuation ratios. Lower interest rates have been offset by rising risk premia to keep expected returns close to average. Instead, the market has priced in future income growth on commercial properties far above the growth rates seen in the data. High implied growth rates are less extreme for nontraditional REIT sectors. Income growth expectations are also less extreme for international listed real estate.
Out of the box: illegal tying and Google’s suite of apps for the Android OS

ABSTRACTThis paper analyses Google’s practice of bundling certain smartphone applications together in a single suite that smartphone manufacturers pre-install on their devices, which is currently u...
Learning Analytics and Its Paternalistic Influences

Learning analytics is a technology that employs paternalistic nudging techniques and predictive measures. These techniques can limit student autonomy, may run counter to student interests and preferences, and do not always distribute benefits back to students–in fact some harms may actually accrue. The paper presents three cases of paternalism in learning analytics technologies, arguing that paternalism is an especially problematic concern for higher education institutions who espouse liberal education values. Three general recommendations are provided that work to promote student autonomy and choice making as a way to protect against risks to student academic freedom.
Financial globalization and market volatility : an empirical appraisal

This paper computes a new financial globalization index for a large sample of countries for 1992-2016. Unlike other measures, the financial globalization index corrects for the heteroscedasticity of global volatility. This leads to a downward adjustment of financial globalization trends for developed, emerging, and frontier markets. The paper also shows that financial globalization reduces market volatility (measured by the volatility of stock returns) in tranquil times, and increases it in turbulent ones. On average, the first effect dominates, so that financial globalization leads to a decrease in market volatility, which is more pronounced in frontier markets.
Going to College Online? A PEST Analysis of MOOCs.

Massively open? College unbound? What are the roots of Massive Open Online Courses (MOOCs), and how much of a trend is it? What promises and anxieties do MOOCs bring to higher education, academic leaders, and faculty? 2013 has witnessed one of the most rapid and enthusiastic adoptions of educational innovation in history, generating numerous discussions on an endless list of questions and issues related to MOOCs and open educational resources. To better understand these questions, this article uses a PEST framework to scan the macro environment through Political, Economic, Social, and Technological lenses. Implications for higher education, faculty, professionals, and students are discussed.
Terahertz absorption of lysozyme in solution

Absorption of radiation by solution is described by its frequency-dependent dielectric function and can be viewed as a specific application of the dielectric theory of solutions. For ideal solutions, the dielectric boundary-value problem separates the polar response into the polarization of the void in the liquid, created by the solute, and the response of the solute dipole. In the case of a protein as a solute, protein nuclear dynamics do not project on significant fluctuations of the dipole moment in the terahertz domain of frequencies and the protein dipole can be viewed as dynamically frozen. Absorption of radiation then reflects the interfacial polarization. Here we apply an analytical theory and computer simulations to absorption of radiation by an ideal solution of lysozyme. Comparison with the experiment shows that Maxwell electrostatics fails to describe the polarization of the protein-water interface and the "Lorentz void," which does not anticipate polarization of the interface by the external field (no surface charges), better represents the data. An analytical theory for the slope of the solution absorption against the volume fraction of the solute is formulated in terms of the cavity field response function. It is calculated from molecular dynamics simulations in good agreement with the experiment. The protein hydration shell emerges as a separate sub-ensemble, which, collectively, is not described by the standard electrostatics of dielectrics.
Exogenous GDF11 induces cardiac and skeletal muscle dysfunction and wasting

Growth differentiation factor 11 (GDF11), a TGF-beta superfamily member, is highly homologous to myostatin and essential for embryonic patterning and organogenesis. Reports of GDF11 effects on adult tissues are conflicting, with some describing anti-aging and pro-regenerative activities on the heart and skeletal muscle while others opposite or no effects. Herein, we sought to determine the in vivo cardiac and skeletal muscle effects of excess GDF11. Mice were injected with GDF11 secreting cells, an identical model to that used to initially identify the in vivo effects of myostatin. GDF11 exposure in mice induced whole body wasting and profound loss of function in cardiac and skeletal muscle over a 14-day period. Loss of cardiac mass preceded skeletal muscle loss. Cardiac histologic and echocardiographic evaluation demonstrated loss of ventricular muscle wall thickness, decreased cardiomyocyte size, and decreased cardiac function 10 days following initiation of GDF11 exposure. Changes in skeletal muscle after GDF11 exposure were manifest at day 13 and were associated with wasting, decreased fiber size, and reduced strength. Changes in cardiomyocytes and skeletal muscle fibers were associated with activation of SMAD2, the ubiquitin-proteasome pathway and autophagy. Thus, GDF11 over administration in vivo results in cardiac and skeletal muscle loss, dysfunction, and death. Here, serum levels of GDF11 by Western blotting were 1.5-fold increased over controls. Although GDF11 effects in vivo are likely dose, route, and duration dependent, its physiologic changes are similar to myostatin and other Activin receptors ligands. These data support that GDF11, like its other closely related TGF-beta family members, induces loss of cardiac and skeletal muscle mass and function.
A chip-based micro-cavity optical parametric oscillator (µOPO)

We report a micro-scale optical parametric oscillator (μOPO). Oscillations are observed at record low threshold values (170 micro-Watts) with highly ideal (97%) signal-to-idler photon emission. High conversion efficiencies (36%) are achieved.
Understanding Aggregate Default Rates of High Yield Bonds

Although the high yield market is now mature, its behavior during business cycle downturns is not well understood. During the severe recessions of 1980-82, when the market was in its infancy, few issuers of speculative bonds defaulted on their obligations to creditors. By contrast, in the mild recession of 1990-91, the default rate soared to 11 percent. These sharply divergent experiences raise the question: How does the high yield market typically respond to a slowing economy?
Virilizing Adrenal Tumor in a 3-Year-Old Girl: Diagnosis by Computed Tomographic Scan and Ultrasound

Virilization in prepubertal children is a rare finding that is characterized by development of pubic hair, clitoral or penile enlargement, accelerated linear growth, and advanced bone age. Prompt diagnosis of the source of excess androgen production is important because of the possibility of a malignant tumor and because rapid acceleration of skeletal maturation may compromise adult stature. Certain causes of virilization, including true precocious puberty, testicular tumors, and congenital adrenal hyperplasia can frequently be excluded by history and physical examination. The major diagnostic problem is often that of preoperatively distinguishing between adrenal and ovarian tumors in virilized females. We describe a 3-year-old girl in whom a small adrenal tumor was accurately localized by computed tomography (CT) scanning and ultrasonography. Report of a Case .—The patient weighed 4,000 g at birth, and no genital abnormalities were noted in the newborn period. Height increased along the 90th-percentile line until the age of
Modulation of Pulsatile Gonadotropin Secretion by Testosterone in Man

In experimental animals, primary testicular deficiency leads to increased LH pulse frequency. Pulsatile FSH secretion has not been well characterized in any species. To determine the effect of testosterone (T) on the pattern of pulsatile gonadotropin secretion in man, we performed frequent blood-sampling studies in six normal men and six men with primary hypogonadism. All primary hypogonadal men were studied 6-8 weeks after stopping T replacement therapy. Five of the six hypogonadal men were restudied 6-8 weeks after treatment with T enanthate (200 mg, im, every 2 weeks; sampling in this group was 2 weeks after their last T injection). Blood sampling was done at 10-min intervals for 12 h in all subjects, and the pattern of episodic LH and FSH secretion was determined. Normal men had a serum T level of 6.3 +/- 0.3 ng/ml (mean +/- SEM), a LH level of 34 +/- 3 ng/ml, and a LH pulse pattern characterized by low frequency (7.6 +/- 0.7 pulses/12 h) and low amplitude (16 +/- 1 ng/ml). Compared to normal men, primary hypogonadal men had a significantly lower T level (2.9 +/- 0.4 ng/ml) and significantly higher LH pulse frequency (13.0 +/- 1.3 pulses/12 h), amplitude (51 +/- 7 ng/ml), and mean level (222 +/- 26 ng/ml). Reinstitution of T replacement therapy in hypogonadal men resulted in a significant increase in the T level (4.7 +/- 0.5 ng/ml) and significant decreases in LH pulse frequency (7.2 +/- 1.6 pulses/12 h) and amplitude (41 +/- 5 ng/ml) as well as mean LH level (75 +/- 15 ng/ml). FSH levels fluctuated in a distinctly pulsatile pattern in all three groups. Differences in pulsatile FSH secretion between primary hypogonadal men before and during T therapy and normal men paralleled those in pulsatile LH secretion in both frequency and amplitude. These results demonstrate that in man 1) diminished T negative feedback results in high frequency (circhoral), high amplitude LH and FSH pulses; 2) T replacement decreased LH and FSH pulse frequency and amplitude as well as mean levels; and 3) the decreased LH and FSH pulse frequency with T treatment implies that T or a metabolite of T acts on the central nervous system to slow the hypothalamic LHRH pulse generator.
Demonstration of Cutaneous Doxorubicin Extravasation by Rhodamine-Filtered Fluorescence Microscopy

Accidental extravasation of the widely used antineoplastic anthracycline doxorubicin (adriamycin) is capable of causing serious and on-going skin and soft tissue necrosis leading to loss of limb function. The only effective cure has been the complete surgical excision of drug-contaminated tissue. Surgical excisions preparatory to skin grafting have often underestimated the extent of drug infiltration into tissue. Using an experimental technique utilizing the drug's natural property of red fluorescence, we were able to effect complete surgical excision by rhodamine fluorescence microscopy in frozen sections of resected skin.
Anaplastic Seminoma: An Analysis of Eight Cases with Literature Review

A retrospective analysis of 80 cases of seminomas treated at the University of Louisville Radiation Center from 1958 to 1979 has been done. Eight cases have been treated with a diagnosis of anaplastic seminoma. This study is a review of the eight cases, along with a review of literature, regarding the prognosis and management of anaplastic seminoma.
Neonatal Ovarian Cysts: Sonographic-Pathologic Correlation

The authors reviewed the prenatal (11 infants) and postnatal (17 infants) sonograms and the clinical, surgical, and pathologic findings in 17 infants with an ovarian cyst to determine the sonographic features and natural history of neonatal ovarian cysts. An uncomplicated cyst (nontwisted, nonhemorrhagic) was completely anechoic and the cyst wall was imperceptible with sonography (five cases). A twisted or hemorrhagic cyst was cystic with a fluid-debris level, cystic with a retracting clot, septated with or without internal echoes, or solid (12 cases). These complicated cysts contained liquid and/or organized hematoma. Eleven of the 12 complicated cysts had a thin, highly echogenic wall. Cyst torsion commonly occurred in utero and could be diagnosed on prenatal sonograms by a typical sonographic appearance (eight cases). All of these infants were asymptomatic after birth. Four infants with hemorrhagic or twisted cysts were symptomatic. All cysts except one that resolved spontaneously were treated surgically, including three twisted cysts that showed no change in size over a 1-8-month interval. All of the cysts were of follicular origin.
Intersective polynomials and Diophantine approximation, II

By applying Schmidt’s lattice method, we prove results on simultaneous Diophantine approximation modulo 1 for systems of polynomials in a single prime variable provided that certain local conditions are met.
CONTAGION EXPOSURE AND PROTECTION TECHNOLOGY

Abstract Individuals adopt diverse measures to prevent contagion during interactions. I propose a model to study the implications of the protection technology on the prevalence of infections and on welfare at different levels of exposure. I find that the effect of aggregate exposure on prevalence and on protection inefficiencies depends crucially on the characteristics of the available protection technology. For example, a vaccine may yield lower infection rates and smaller costs of decentralization as exposure increases, but only if the protection it provides is sufficiently long lasting. Other protection technologies, such as those used for cybersecurity, may lead to coordination failures. The analysis has implications for disease eradication, the desirability of interventions with and without universal vaccines, and coordination failures in cybersecurity.
Factors That Influence the Recruitment and Retention of Nurses in Public Health Agencies

Objective:Given challenges to recruiting nurses to public health and the growth in national policies focused on population health, it is crucial that public health agencies develop strategies to su...
Mining Bad Credit Card Accounts from OLAP and OLTP

Credit card companies classify accounts as a good or bad based on historical data where a bad account may default on payments in the near future. If an account is classified as a bad account, then further action can be taken to investigate the actual nature of the account and take preventive actions. In addition, marking an account as "good" when it is actually bad, could lead to loss of revenue - and marking an account as "bad" when it is actually good, could lead to loss of business. However, detecting bad credit card accounts in real time from Online Transaction Processing (OLTP) data is challenging due to the volume of data needed to be processed to compute the risk factor. We propose an approach which precomputes and maintains the risk probability of an account based on historical transactions data from offline data or data from a data warehouse. Furthermore, using the most recent OLTP transactional data, risk probability is calculated for the latest transaction and combined with the previously computed risk probability from the data warehouse. If accumulated risk probability crosses a predefined threshold, then the account is treated as a bad account and is flagged for manual verification.