Miracle-dz/UniFAR-FTUs huggingface dataset:
Performance analysis of direct N-body algorithms on highly distributed systems

This work has been submitted to the IEEE for possible publication. Copyright may be transferred without notice, after which this version may no longer be accessible. Abstract— We present a performance analysis of different parallelization schemes for direct codes used in the simulation of astrophysical stellar systems. These codes compute the gravita-tional interaction among stars in an exact way and have a computational complexity of O(N 2). Significant improvement in the performance of direct N-body codes can be obtained by means of general purpose massively parallel supercomputers and of special purpose computers like GRAPE hardware. We compare the performance of parallel algorithms on different architectures including a cluster, a supercomputer and two computational grids. The best performance is obtained in combination with GRAPE-6 hardware but highly distributed computational Grids also appear very promising. The simulation of a globular cluster containing about one million stars, currently one of the most challenging numerical problems in astrophysics, is feasible only in combination with GRAPE hardware or on massively parallel architectures.
Flow control and bandwidth management in next generation Internets

The Internet has traditionally relied on end-to-end congestion control performed at the transport layer, where sources reduce their offered traffic only after congestion sets in. By then, network resources have been wasted and effective throughput compromised. In next generation Internets, the delay-bandwidth product is large and bandwidth is a precious resourse. Hence, in this paper we present a link layer flow control for Internet backbones over ATM using the ABR service and flow control. We describe a backpressure mechanism that reduces packet losses and promotes effective utilization of allocated and unused resources along backbone links. We then show how to perform dynamic renegotiation of allocated backbone resources based on our flow control approach and on class based queueing.
Measurement of Cough Aerodynamics in Healthy Adults

Importance: Cough is a critical human reflex and also among the most frequent symptoms in medicine. Despite the prevalence of disordered cough in laryngeal pathologies, comprehensive and quantitative evaluation of cough in these patients is lacking. Objective: Herein we seek to establish normative values for cough aerodynamics to provide a population standard for reference in future studies. Design, Setting, and Participants: Healthy subjects were recruited from an outpatient clinic to perform voluntary cough. Subjects were instructed on the technique for maximal voluntary cough production with measurements recorded on pneumotachograph. Fifty-two subjects were studied, including 29 women and 23 men with a mean age of 51.6 and 52.3 years, respectively. Main Outcomes and Measures: Cough peak airflow, peak pressure, and expiratory rise time. Results were stratified by age, gender, and height. Results: Peak airflow demonstrated significant differences across age, gender, and height, with flow increasing according to increasing height. Peak cough pressure also increased with height and was significantly greater in males versus females. Expiratory rise time, the time from glottal opening to peak airflow, did not vary with age or height but was statistically significantly longer in women. Conclusions: Cough aerodynamics can be readily measured objectively in the outpatient setting. Expiratory rise time, peak flow, and peak pressure are important aspects of each cough epoch. Normative data provided herein can be used for future studies of patients with laryngotracheal disorders, and these cough parameters may prove to be simple, accessible, and repeatable outcome measures.
Systems for Safety and Autonomous Behavior in Cars: The DARPA Grand Challenge Experience

In this paper, we review technologies for autonomous ground vehicles and their present capabilities in research and in the automotive market. We outline technology requirements for enhanced functions and for infrastructure development. Since the recent Grand Challenge competition is a major force to advance technology in this field, we specifically refer to our experiences in developing a participating vehicle. We present a multisensor platform that has been proven in an off-road environment. It combines different sensing modalities that inherently yield uncertain information. Finite-state machines are formulated to generate rule-based autonomous behavior that enables fully autonomous off-road driving. Overall, the intent of the paper is to evaluate approaches and technologies used in the two Grand Challenges as they contribute to the needs of autonomous cars on the road
The Role of Statins in Chronic Kidney Disease

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality not only amongst the general population, but also in patients with chronic kidney disease (CKD). Persons with CKD are much more likely to die of CVD than to experience kidney failure. Clinical trials have demonstrated that statins are gaining widespread acceptance as a principal therapy for the primary and secondary prevention of atherosclerosis and CVD. In CKD patients the role of statins in primary prevention of CVD remains to be clarified. The absolute benefit of treatment with a statin seems to be greater among nondialysis-dependent-CKD patients. Studies in end-stage renal disease patients on dialysis did not confirm these results. Recently, however, the Study of Heart and Renal Protection (SHARP) has suggested that statins with ezetimibe may be beneficial even in dialysis patients. Clinical studies with statins on proteinuria reduction and renal disease progression have yielded conflicting results. Some studies have shown a prominent reduction in proteinuria, while other studies have shown that statins had no effect or may cause proteinuria at high doses. This review examines the clinical evidence of the observed benefits of kidney function with the use of this drug category in CKD patients.
A Comparison and Calibration of a Wrist-Worn Blood Pressure Monitor for Patient Management: Assessing the Reliability of Innovative Blood Pressure Devices

Background Clinical guidelines recommend monitoring of blood pressure at home using an automatic blood pressure device for the management of hypertension. Devices are not often calibrated against direct blood pressure measures, leaving health care providers and patients with less reliable information than is possible with current technology. Rigorous assessments of medical devices are necessary for establishing clinical utility. Objective The purpose of our study was 2-fold: (1) to assess the validity and perform iterative calibration of indirect blood pressure measurements by a noninvasive wrist cuff blood pressure device in direct comparison with simultaneously recorded peripheral and central intra-arterial blood pressure measurements and (2) to assess the validity of the measurements thereafter of the noninvasive wrist cuff blood pressure device in comparison with measurements by a noninvasive upper arm blood pressure device to the Canadian hypertension guidelines. Methods The cloud-based blood pressure algorithms for an oscillometric wrist cuff device were iteratively calibrated to direct pressure measures in 20 consented patient participants. We then assessed measurement validity of the device, using Bland-Altman analysis during routine cardiovascular catheterization. Results The precalibrated absolute mean difference between direct intra-arterial to wrist cuff pressure measurements were 10.8 (SD 9.7) for systolic and 16.1 (SD 6.3) for diastolic. The postcalibrated absolute mean difference was 7.2 (SD 5.1) for systolic and 4.3 (SD 3.3) for diastolic pressures. This is an improvement in accuracy of 33% systolic and 73% diastolic with a 48% reduction in the variability for both measures. Furthermore, the wrist cuff device demonstrated similar sensitivity in measuring high blood pressure compared with the direct intra-arterial method. The device, when calibrated to direct aortic pressures, demonstrated the potential to reduce a treatment gap in high blood pressure measurements. Conclusions The systolic pressure measurements of the wrist cuff have been iteratively calibrated using gold standard central (ascending aortic) pressure. This improves the accuracy of the indirect measures and potentially reduces the treatment gap. Devices that undergo auscultatory (indirect) calibration for licensing can be greatly improved by additional iterative calibration via intra-arterial (direct) measures of blood pressure. Further clinical trials with repeated use of the device over time are needed to assess the reliability of the device in accordance with current and evolving guidelines for informed decision making in the management of hypertension. Trial Registration ClinicalTrials.gov NCT03015363; https://clinicaltrials.gov/ct2/show/NCT03015363 (Archived by WebCite at http://www.webcitation.org/6xPZgseYS)
Efficient Communications in Training Large Scale Neural Networks

We consider the problem of how to reduce the cost of communication that is required for the parallel training of a neural network. The state-of-the-art method, Bulk Synchronous Parallel Stochastic Gradient Descent (BSP-SGD), requires many collective communication operations, like broadcasts of parameters or reductions for partial gradient aggregations, which for large messages quickly dominates overall execution time and limits parallel scalability. To address this problem, we develop a new technique for collective operations, referred to as Linear Pipelining (LP). It is tuned to the message sizes that arise in BSP-SGD, and works effectively on multi-GPU systems. Theoretically, the cost of LP is invariant to P, where P is the number of GPUs, while the cost of the more conventional Minimum Spanning Tree (MST) scales like O(log P). LP also demonstrates up to 2x higher bandwidth than Bidirectional Exchange (BE) techniques that are widely adopted by current MPI implementations. We apply these collectives to BSP-SGD, showing that the proposed implementations reduce communication bottlenecks in practice while preserving the attractive convergence properties of BSP-SGD.
Return on Marketing: Using Customer Equity to Focus Marketing Strategy

The authors present a unified strategic framework that enables competing marketing strategy options to be traded off on the basis of projected financial return, which is operationalized as the change in a firm's customer equity relative to the incremental expenditure necessary to produce the change. The change in the firm's customer equity is the change in its current and future customers’ lifetime values, summed across all customers in the industry. Each customer's lifetime value results from the frequency of category purchases, average quantity of purchase, and brand-switching patterns combined with the firm's contribution margin. The brand-switching matrix can be estimated from either longitudinal panel data or cross-sectional survey data, using a logit choice model. Firms can analyze drivers that have the greatest impact, compare the drivers’ performance with that of competitors’ drivers, and project return on investment from improvements in the drivers. To demonstrate how the approach can be implemented in a specific corporate setting and to show the methods used to test and validate the model, the authors illustrate a detailed application of the approach by using data from the airline industry. Their framework enables what-if evaluation of marketing return on investment, which can include such criteria as return on quality, return on advertising, return on loyalty programs, and even return on corporate citizenship, given a particular shift in customer perceptions. This enables the firm to focus marketing efforts on strategic initiatives that generate the greatest return.
An adaptive two-phase approach to WiFi location sensing

Environmental variations cause significant fluctuations in WiFi signals in the same location over time, rendering traditional RF-to-location pre-trained maps quickly obsolete. To solve this problem, we use a two-phase approach to determining the user's location. The first phase utilizes traditional pattern-matching to identify the general location, and a second phase applies logistic regression to distinguish between finer-grained locations. An adaptive calibration system allows the user to re-train and dynamically update the signal strength maps to account for the fluctuated signals. We show that our two-phase approach is able to achieve generally high accuracy (-95%) and over in areas of high signal fluctuations due to heavy access point and human density
Evaluation of filtering mechanisms for MPEG video communications

In this paper, we evaluate two video filtering mechanisms for MPEG-1 video, namely low-pass filtering and selective frame dropping. The evaluation provides tradeoffs between the reduction achieved in bandwidth requirements and the perceptual quality of the video sequences delivered to the client. Extensive experiments revealed that these filtering mechanisms result in a significant reduction in bandwidth requirements while maintaining acceptable perceptual quality.
168 Gb/s/λ Direct-Detection 64-QAM SSB Nyquist-SCM Transmission over 80 km Uncompensated SSMF at 4.54 b/s/Hz net ISD using a Kramers-Kronig Receiver

Using the recently-proposed Kramers-Kronig receiver DSP scheme, we achieved 4∗168 Gb/s 35 GHz-spaced WDM single-polarization direct-detection 64-QAM SSB Nyquist-SCM transmission over 80 km of uncompensated SSMF at a record net ISD of 4.54 b/s/Hz.
Analysis of high frequency fetal heart rate variability using empirical mode decomposition

We used empirical mode decomposition (EMD) to assess the high frequency information of fetal HRV during different conditions of fetal activity. Beat-to-beat data of thirteen normal fetuses at term (36 to 40 gestation weeks) were obtained from abdominal ECG signals. In addition, corporal and breathing fetal movements were simultaneously observed using ultrasound B mode images. High frequency components of fetal HRV data were obtained by applying the EMD and by reconstructing the signals from components having frequencies higher than 0.3 Hz, according to the lowest frequency of fetal breathing movements observed in our data. Our results show significant differences in the power of high frequency components for episodes only with breathing movements vs no movements and vs. episodes having corporal movements (p<0.05). In conclusion, EMD seems to be a useful tool to analyze the effect of the FBM on non-stationary fetal HR time series
Segmenting MR Images Using Fully-Tuned Radial Basis Functions (RBF)

Segmenting medical images into different tissues is an important task in medical image analysis, e.g., classifying every voxel of input image into different tissue types: CSF, gray matter and white matter. This paper investigates the fully-tuned radial basis function (RBF) and compares it with the traditional fuzzy c-mean (FCM) clustering algorithm in MR image segmentation. It turns out that FCM is not only biased by the number of voxels in different groups, but also by the intensity differences between different tissue groups, while the fully-tuned RBF captures the multi-Gaussian distribution of the image intensities very well and thus it can be used to segment image intensities accurately. Moreover, in order to generate spatially smooth segmentation results, a Markov random field model is applied to the segmentation results of the fully-tuned RBF algorithm. Experimental results show that fully-tuned RBF method can capture the tissue intensity distribution more accurately than the FCM algorithm
Stabilizing high voltage LiCoO2 cathode in aqueous electrolyte with interphase-forming additive

Aqueous lithium ion batteries (ALIBs) receive increasing attention due to their intrinsic non-flammable nature. Their practical application, however, has been prevented by the poor electrochemical stability of aqueous electrolytes, which severely restricts the choice of anode and cathode materials for such batteries and leads to low energy densities. It has been demonstrated that “water-in-salt” electrolytes can provide an expanded voltage window of ∼3.0 V, which can accommodate electrode materials that were otherwise forbidden in conventional aqueous electrolytes. In this study, we showed that the presence of an additive could further stabilize the aqueous electrolyte at a high voltage cathode surface. By forming a cathode electrolyte interphase (CEI) through electrochemical oxidation of tris(trimethylsilyl) borate (TMSB), we successfully stabilized LiCoO2 in water-in-salt electrolyte at a high cut-off voltage that corresponds to 0.7e electron charge transfer. To the best of our knowledge, this is also the first electrolyte additive known to form an interphase in aqueous electrolytes. The formed CEI significantly suppressed electrolyte oxidation as well as cobalt dissolution from LiCoO2 into electrolytes, allowing LiCoO2 to be stably charged/discharged at a higher cut-off voltage with a high capacity utilization of 170 mA h g−1. When paired with an Mo6S8 anode, the 2.5 V aqueous full cell delivered a high energy density of 120 W h kg−1 for 1000 cycles with an extremely low capacity decay rate of 0.013% per cycle.
birth: the generation r study Explaining educational inequalities in preterm

Background: Although a low socioeconomic status has consistently been associated with an increased risk of preterm birth, little is known about the pathways through which socioeconomic disadvantage influences preterm birth. Aim: To examine mechanisms that might underlie the association between the educational level of pregnant women as an indicator of socioeconomic status, and preterm birth. Methods: The study was nested in a population-based cohort study in the Netherlands. Information was available for 3830 pregnant women of Dutch origin. Findings: The lowest-educated pregnant women had a statistically significant higher risk of preterm birth (odds ratio (OR) = 1.89 (95% CI 1.28 to 2.80)) than the highest educated women. This increased OR was reduced by up to 22% after separate adjustment for age, height, preeclampsia, intrauterine growth restriction, financial concerns, long-lasting difficulties, psychopathology, smoking habits,
A combination of VEGF 165 / HGF genes is more effective in blood vessels formation than ANGPT 1 / VEGF 165 genes in an in vivo rat model

Background: The angiogenic potential of an experimental therapy consisting in an administration of the genes for vascular endothelial growth factor (VEGF165) in combination with hepatocyte growth factor (HGF) or angiopoitein-1 (ANGPT1) has already been studied. However, there is still little known which combination of genes is the most efficient. Methods: Two bicistronic plasmid vectors carrying pIRES/VEGF165/HGF and pIRES/ANGPT1/ VEGF165 and an empty plasmid (control group) were constructed. 30 rats were divided into three equal groups: pIRES/VEGF165/HGF, pIRES/ANGPT1/VEGF165 and control group (empty plasmid). The plasmids were injected in the hind limbs of the animals and 12 weeks later they were euthanized and tissue samples from the thigh muscle were harvested. Then, under a microscope, vessels stained for the alpha-smooth muscle actin (α-SMA) and factor VIII (FVIII) were counted. Results: The average number of SMA+ or FVIII+ blood vessels in the pIRES/VEGF/ HGF group was 8.96±3.10 and 10.88±2.70, respectively. The angiogenesis was less effective after ANGPT1/VEGF injection and the mean value was 7.12±3.30 for α-SMA+ and 8.63±3.63 for FVIII+ vessels. The average number of SMA+ and FVIII+ vessels in the control group was 4.62±2.46 and 5.82±2.42, respectively. All differences were statistically significant and P values were <0.01. Conclusions: In a rat model, the combination VEGF165 and HGF genes is more effective in the neovascularization process than VEGF165 and ANGPT1 and more effective than the injection of an empty plasmid.
Fast Learning VIEWNET Architectures for Recognizing 3-D Objects from Multiple 2-D Views

National Science Foundation (IRI-90-24877); Office of Naval Research (N00014-92-J-1309); Air Force Office of Scientific Research (F49620-92-J-0499); Advanced Research Projects Agency (AFOSR 90-0083, ONR N00014-92-J-4015)
Particle size distribution and estimated carbon flux across the Arabian Sea oxygen minimum zone

The goal of the Arabian Sea section of the TARA oceans expedition was to study large particulate matter (LPM> 100 µm) distributions and possible impact of associ- ated midwater biological processes on vertical carbon export through the oxygen minimum zone (OMZ) of this region. We propose that observed spatial patterns in LPM distribution resulted from the timing and location of surface phytoplank- ton bloom, lateral transport, microbial processes in the core of the OMZ, and enhanced biological processes mediated by bacteria and zooplankton at the lower oxycline. Indeed, satellite-derived net primary production maps showed that the northern stations of the transect were under the influence of a previous major bloom event while the most southern sta- tions were in a more oligotrophic situation. Lagrangian sim- ulations of particle transport showed that deep particles of the northern stations could originate from the surface bloom while the southern stations could be considered as driven by 1-D vertical processes. In the first 200 m of the OMZ core, minima in nitrate concentrations and the intermediate nepheloid layer (INL) coincided with high concentrations of 100 µm< LPM< 200 µm. These particles could correspond to colonies of bacteria or detritus produced by anaerobic mi- crobial activity. However, the calculated carbon flux through this layer was not affected. Vertical profiles of carbon flux in- dicate low flux attenuation in the OMZ, with a Martin model b exponent value of 0.22. At three stations, the lower oxy- cline was associated to a deep nepheloid layer, an increase of calculated carbon flux and an increase in mesozooplank- ton abundance. Enhanced bacterial activity and zooplankton feeding in the deep OMZ is proposed as a mechanism for the observed deep particle aggregation. Estimated lower flux at- tenuation in the upper OMZ and re-aggregation at the lower oxycline suggest that OMZ may be regions of enhanced car- bon flux to the deep sea relative to non OMZ regions.
A Saliency Model Predicts Fixations in Web Interfaces

User interfaces are visually rich and complex. Consequently, it is difficult for designers to predict which locations will be attended to first within a display. Designers currently depend on eye tracking data to determine fixated locations, which are naturally associated with the allocation of attention. A computational saliency model can make predictions about where individuals are likely to fixate. Thus, we propose that the saliency model may facilitate successful interface development during the iterative design process by providing information about an interface’s stimulus-driven properties. To test its predictive power, the saliency model was used to render 50 web page screenshots; eye tracking data were gathered from participants on the same images. We found that the saliency model predicted fixated locations within web page interfaces. Thus, using computational models to determine regions high in visual saliency during web page development may be a cost effective alternative to eye tracking. Author