Miracle-dz/UniFAR-FTUs huggingface dataset:
Analysis of friction effects on satellite antenna driving mechanism with clearance joints

The existence of clearance in joints of mechanism is inevitable. In this paper, the friction effects in clearance joints on dynamic responses of driving mechanism of satellite antenna are studied. Considering clearances in joints, the contact force model in clearance joints is established using a nonlinear continuous contact force model and the friction effect is considered by using a modified Coulomb friction model. Then the dual-axis driving mechanism of satellite antenna with clearance joints is used as the application example. The numerical simulation of dual-axis driving mechanism with clearance joints is presented. The friction effects of clearance joint on dynamic responses of the dual-axis driving mechanism are discussed and analyzed quantitatively for four cases with different friction coefficients. The investigation results show that the increase of friction coefficient will decrease the vibration amplitude of the driving mechanism system.
Hypoxia Affects Neprilysin Expression Through Caspase Activation and an APP Intracellular Domain-dependent Mechanism

While gene mutations in the amyloid precursor protein (APP) and the presenilins lead to an accumulation of the amyloid β-peptide (Aβ) in the brain causing neurodegeneration and familial Alzheimer's disease (AD), over 95% of all AD cases are sporadic. Despite the pathologies being indistinguishable, relatively little is known about the mechanisms affecting generation of Aβ in the sporadic cases. Vascular disorders such as ischaemia and stroke are well established risk factors for the development of neurodegenerative diseases and systemic hypoxic episodes have been shown to increase Aβ production and accumulation. We have previously shown that hypoxia causes a significant decrease in the expression of the major Aβ-degrading enzyme neprilysin (NEP) which might deregulate Aβ clearance. Aβ itself is derived from the transmembrane APP along with several other biologically active metabolites including the C-terminal fragment (CTF) termed the APP intracellular domain (AICD), which regulates the expression of NEP and some other genes in neuronal cells. Here we show that in hypoxia there is a significantly increased expression of caspase-3, 8, and 9 in human neuroblastoma NB7 cells, which can degrade AICD. Using chromatin immunoprecipitation we have revealed that there was also a reduction of AICD bound to the NEP promoter region which underlies the decreased expression and activity of the enzyme under hypoxic conditions. Incubation of the cells with a caspase-3 inhibitor Z-DEVD-FMK could rescue the effect of hypoxia on NEP activity protecting the levels of AICD capable of binding the NEP promoter. These data suggest that activation of caspases might play an important role in regulation of NEP levels in the brain under pathological conditions such as hypoxia and ischaemia leading to a deficit of Aβ clearance and increasing the risk of development of AD.
Complex structure of cytochrome c–cytochrome c oxidase reveals a novel protein–protein interaction mode

Mitochondrial cytochrome c oxidase (CcO) transfers electrons from cytochrome c (Cyt.c) to O2 to generate H2O, a process coupled to proton pumping. To elucidate the mechanism of electron transfer, we determined the structure of the mammalian Cyt.c–CcO complex at 2.0‐Å resolution and identified an electron transfer pathway from Cyt.c to CcO. The specific interaction between Cyt.c and CcO is stabilized by a few electrostatic interactions between side chains within a small contact surface area. Between the two proteins are three water layers with a long inter‐molecular span, one of which lies between the other two layers without significant direct interaction with either protein. Cyt.c undergoes large structural fluctuations, using the interacting regions with CcO as a fulcrum. These features of the protein–protein interaction at the docking interface represent the first known example of a new class of protein–protein interaction, which we term “soft and specific”. This interaction is likely to contribute to the rapid association/dissociation of the Cyt.c–CcO complex, which facilitates the sequential supply of four electrons for the O2 reduction reaction.
Math Indexer and Searcher under the Hood: History and Development of a Winning Strategy

This paper describes and summarizes experiences of Masaryk University team MIRMU with the mathematical search performed for the NTCIR pilot Math Task. Our approach is the similarity search based on MathML Canonicalization and second generation of scalable full text search engine Math Indexer and Searcher (MIaS) with attested state-of-the-art information retrieval techniques. The capability of MIaS system in terms of the math query notation, normalization, combining math with textual query tokens was deployed by submitting multiple runs with four query notations provided, and with results merged from multiple queries. The analysis of the evaluation results shows that the system performs best using TeX queries that are translated and canonicalized to Content MathML.
ShowMotion: camera motion based 3D design review

We describe a new interactive system for 3D design review, built to exploit the visual perception cue of motion parallax, in order to enhance shape perception and aesthetic evaluation. Traditional CAD applications typically use "bookmarked" static views for design evaluation. In our system, we replace static views with moving "shots" interspersed with cinematic visual transitions. Furthermore, users can access shots by picking object features on the 3D model, which invokes a spatial search over all shots, selects the ones deemed relevant to the feature, and plays back those shots. In this paper we describe the rationale behind this system, the main components, the implementation of the search technique, and the initial user evaluation of the system.
Giant Cell Arteritis and Polymyalgia Rheumatica

Patients suspected of giant cell arteritis or polymyalgia rheumatica are often referred to the otolaryngologist for temporal artery biopsy. These patients may initially present to the otolaryngologist with symptoms referable to the head and neck. a comprehensive review of these two interrelated disorders is provided, with emphasis on head and neck manifestations and features of obtaining the temporal artery biopsy specimen.
From the gaming experience to the wider user experience

In this paper we discuss the different elements of the gaming experience and their relation to other concepts within HCI. The objective is to showcase how the different elements that form the gaming experience can be used to understand further issues regarding user experience. The objectives of games are, after all, to provide players with a positive experience. Understanding the elements that eventually lead players to have a positive experience should provide feedback about the wider user experience concept. Although video-games and non-game applications seem to be two different domains of study, in terms of experience, they both aim to improve the individual's experience.
Vitamin D Deficiency Is Prevalent in Girls and Women With Rett Syndrome

Objectives: The aim of the study was to determine the prevalence of vitamin D deficiency and identify the relation between 25-hydroxyvitamin D (25-(OH)D) levels and the consumption of dietary sources of vitamin D or exposure to anticonvulsants in girls and women with Rett syndrome (RTT). Subjects and Methods: Retrospective review of the medical records of 284 girls and women with RTT to determine serum 25-(OH)D and parathyroid hormone levels, nutritional status, dietary sources of vitamin D, exposure to anticonvulsants, degree of mobility, and MECP2 status. Results: Twenty percent of girls and women who were tested (n = 157) had 25-(OH)D levels <50 nmol/L. Multivitamin supplements, vitamin D–fortified milk, and commercial formulas were consumed by 40%, 52%, and 54%, respectively. Anticonvulsants were used by 57%, and 39% ambulated independently. Median 25-(OH)D levels were lower in individuals who did not receive multivitamin supplements (P < 0.05) or commercial formulas (P < 0.001) than in those who did. Median 25-(OH)D levels differed (P < 0.01) among racial and ethnic groups, but the number in some groups was small. Nutritional status, use of anticonvulsants, degree of mobility, and MECP2 status did not influence 25-(OH)D levels. Conclusions: Vitamin D deficiency is prevalent in girls and women with RTT. The use of multivitamin supplements or commercial formulas is associated with improved vitamin D levels. Attention to vitamin D may enhance bone mineral deposition and reduce the frequency of bone fractures in these individuals.
Ensemble of state-of-the-art methods for polyphonic music comparison

Kjell Lemstrom was supported by the Academy of Finland (Grant 108547). David Rizo and Jose M. Inesta are supported the Spanish Ministry projects: TIN2006–14932–C02 and Consolider Ingenio 2010 (MIPRCV, CSD2007-00018), partially supported by EU ERDF and the Pascal Network of Excellence.
Passivity-Based Full-Body Force Control for Humanoids and Application to Dynamic Balancing and Locomotion

This paper proposes a passivity-based hierarchical full-body motion controller for force-controllable multi-DOF humanoid robots. The task-space forces are treated in a uniform manner for a variety of position/force tracking and force/moment compensation. The contact force closure is optimally solved and transformed directly into the joint torques in real-time without any joint trajectory planning. With this framework, we introduce gravity compensation at the lowest layer of the controller that makes the closed-loop system passive with respect to additional inputs as well as external forces. Furthermore, we propose two upper-layers: one layer controls the ground reaction forces, which enables the robot keep the dynamic balance. The other layer is the another passification control, which constructs an invariant manifold that prevents the robot from falling during walking. Four realistic dynamic simulations: balanced squatting, reaching, externally driven, or speed-controlled walking with disturbances demonstrate the effectiveness of the proposed methods
K-mean clustering and correlation analysis in recognition of weather impact on radio signal

This paper deals with using a K-means clustering which is used for decision what parameter related to weather affects a propagation of radio waves in mobile telecommunication network. There were analysed parameters from a meteorological service as well as the parameters related to Global System of Mobile Communication network. For this purpose, we studied and used theory of data mining. The second part of the paper is focused on the significant weather parameters as results of K-means analyse. Consequently, there have been found some dependencies between weather conditions and receive level using a mathematical tools of correlation analysis via MATLAB.
Rootkit-resistant disks

Rootkits are now prevalent in the wild. Users affected by rootkits are subject to the abuse of their data and resources, often unknowingly. Suchmalware becomes even more dangerous when it is persistent-infected disk images allow the malware to exist across reboots and prevent patches or system repairs from being successfully applied. In this paper, we introduce rootkit-resistant disks (RRD) that label all immutable system binaries and configuration files at installation time. During normal operation, the disk controller inspects all write operations received from the host operating system and denies those made for labeled blocks. To upgrade, the host is booted into a safe state and system blocks can only be modified if a security token is attached to the disk controller. By enforcing immutability at the disk controller, we prevent a compromised operating system from infecting its on-disk image. We implement the RRD on a Linksys NSLU2 network storage device by extending the I/O processing on the embedded disk controller running the SlugOS Linux distribution. Our performance evaluation shows that the RRD exhibits an overhead of less than 1% for filesystem creation and less than 1.5% during I/O intensive Postmark benchmarking. We further demonstrate the viability of our approach by preventing a rootkit collected from the wild from infecting the OS image. In this way, we show that RRDs not only prevent rootkit persistence, but do so in an efficient way.
Effects of a calcium phosphate-coated and anodized titanium surface on early bone response.

PURPOSE The aim of this study was to evaluate the effectiveness of a calcium phosphate (CaPO4)-coated and anodized titanium surface in vitro and in vivo. MATERIALS AND METHODS A turned surface was employed as a negative control. A sandblasted/acid-etched surface and an anodized surface were used as positive controls, and a CaPO4-coated and anodized (CPA) surface was investigated as the experimental group. Surface characteristics were analyzed with field emission scanning electron microscopy, energy dispersive spectroscopy, and confocal laser scanning microscopy. In vitro osteoblastic differentiation was evaluated by alkaline phosphatase assay. In vivo bone response was analyzed using bone-to-implant contact (BIC) ratios and bone area (BA) of 2- and 4-week specimens obtained from six rabbits. RESULTS The means and standard deviations for average height deviation (S(a)) and developed surface area ratio (S(dr)) were 0.32 ± 0.03 μm and 3.6% ± 1.5% for the turned group, 1.36 ± 0.11 μm and 56.7% ± 16.1% for the sandblasted/acid-etched group, 0.68 ± 0.02 μm and 50.9% ± 2.9% for the anodized group, and 0.67 ± 0.11 μm and 50.0% ± 16.9% for the CPA group. There were no significant differences in alkaline phosphatase activity among the groups at 7 and 14 days. In the in vivo experiment, the CPA group exhibited a significantly higher BIC ratio than the turned group, and the anodized and CPA groups showed significantly higher BA values than the others after 2 weeks. At 4 weeks, there was no significance in either BIC ratios or BA values among the groups. CONCLUSION A CaPO(4) coating on an anodized surface may induce rapid osseointegration at the bone-implant interface and more bone formation near the implant surface.
File clustering using naming conventions for legacy systems

Decomposing complex software systems into conceptually independent subsystems represents a significant software engineering activity that receives considerable research attention. Most of the research in this domain deals with the source code; trying to cluster together files which are conceptually related. In this paper we propose using a more informal source of information: file names.We present an experiment which shows that file naming convention is the best file clustering criteria for the software system we are studying.Based on the experiment results, we also sketch a method to build a conceptual browser on a software system.
Finding a good query-related topic for boosting pseudo-relevance feedback

Pseudo-relevance feedback (PRF) via query expansion (QE) assumes that the top-ranked documents from the first-pass retrieval are relevant. The most informative terms in the pseudo-relevant feedback documents are then used to update the original query representation in order to boost the retrieval performance. Most current PRF approaches estimate the importance of the candidate expansion terms based on their statistics on document level. However, a document for PRF may consist of different topics, which may not be all related to the query even if the document is judged relevant. The main argument of this article is the proposal to conduct PRF on a granularity smaller than on the document level. In this article, we propose a topic-based feedback model with three different strategies for finding a good query-related topic based on the Latent Dirichlet Allocation model. The experimental results on four representative TREC collections show that QE based on the derived topic achieves statistically significant improvements over a strong feedback model in the language modeling framework, which updates the query representation based on the top-ranked documents. © 2011 Wiley Periodicals, Inc.
Lockdown: A Safe and Practical Environment for Security Applications (CMU-CyLab-09-011)

We describe, build, and evaluate Lockdown, a system that significantly increases the level of security for online transactions, even on a platform infested with malicious code. Lockdown provides the user with a highly-protected, yet also highly-constrained trusted environment for performing online transactions, as well as a high-performance, general-purpose environment for all other (non-security-sensitive) applications. A simple, user-friendly external interface allows the user to securely learn which environment is active and easily switch between them. We focus on making Lockdown deployable and usable today. Lockdown works with both Windows and Linux, and provides immediate improvements to security-sensitive tasks while imposing, on average, only 3% memory overhead and 2–7% storage overhead on non-security-related tasks.
Non‐stereoscopic cues in the Random‐Dot E stereotest: results for adult observers *

The purpose of this study was to investigate performance on the Random‐Dot E (ROE) stereotest under binocular and monocular non‐stereoscopic viewing conditions. Sixteen adult observers with normal vision were tested with the RDE stereotest. Four new RDE tests were shown to each observer in varying combinations of monocular viewing, binocular but non‐stereoscopic viewing, and normal binocular viewing conditions. The test conditions were masked (where possible) and were presented in pseudo‐random order. Control experiments were also conducted using the Frisbv stereotest. Fifteen of the sixteen observers could discern some differences between the plates monocularly and therefore satisfied the passing criterion of the RDE test. Under these conditions, no observers could discern the stereoscopic E figure nor did any observer report a sensation of depth. No observer satisfied the passing criterion of the Frisby test monocularly. We conclude that caution should be used when interpreting results from the RDE stereotest, since adult observers could discern some differences between the test plates monocularly.
Performance of a joint radar-communication system in doubly-selective channels

When radar and communication systems are co-located and operating simultaneously in the same frequency band, interference can be addressed by designing the systems to share resources. This paper develops a framework for cooperative operation of bistatic radar and wireless communication systems. We adopt a low-complexity linear minimum mean square error (LMMSE) optimal pilot symbol aided modulation (PSAM) scheme, and show the achievability region of the joint radar-communication system designed for simultaneous operation in a wireless channel that is both frequency and time-selective.
Learning Spike Train to Spike Train Transformations in Multilayer Feedforward Neuronal Networks

We address the problem of learning temporally precise spike train to spike train transformations in multilayer feedforward networks of spiking neurons. We pursue a framework based strictly on spike timing, that is, one that avoids invoking concepts pertaining to spike rates. The proposed error functional compares the spike train emitted by the output neuron of the network to the desired spike train by way of their putative impact on a virtual postsynaptic neuron. This formulation sidesteps the need for spike alignment, which in turn leads to closed form solutions for all quantities of interest. Next, through a perturbation analysis of individual spike times and synaptic weights of the output as well as the intermediate neurons in the network, we derive the gradients of the error functional with respect to the said entities. Learning proceeds via a gradient descent mechanism that leverages these quantities. Simulation experiments demonstrate the efficacy of the proposed learning framework. The experiments also highlight the effects of sparse input and asymmetries between synapses on excitatory and inhibitory neurons.
Blue noise sampling with controlled aliasing

In this article we revisit the problem of blue noise sampling with a strong focus on the spectral properties of the sampling patterns. Starting from the observation that oscillations in the power spectrum of a sampling pattern can cause aliasing artifacts in the resulting images, we synthesize two new types of blue noise patterns: step blue noise with a power spectrum in the form of a step function and single-peak blue noise with a wide zero-region and no oscillations except for a single peak. We study the mathematical relationship of the radial power spectrum to a spatial statistic known as the radial distribution function to determine which power spectra can actually be realized and to construct the corresponding point sets. Finally, we show that both proposed sampling patterns effectively prevent structured aliasing at low sampling rates and perform well at high sampling rates.
Hip arthroscopy protocol: expert opinions on post-operative weight bearing and return to sports guidelines

Abstract The objectives of this study are to survey the weight-bearing limitation practices and delay for returning to running and impact sports of high volume hip arthroscopy orthopedic surgeons. The study was designed in the form of expert survey questionnaire. Evidence-based data are scares regarding hip arthroscopy post-operative weight-bearing protocols. An international cross-sectional anonymous Internet survey of 26 high-volume hip arthroscopy specialized surgeons was conducted to report their weight-bearing limitations and rehabilitation protocols after various arthroscopic hip procedures. The International Society of Hip Arthroscopy invited this study. The results were examined in the context of supporting literature to inform the studies suggestions. Four surgeons always allow immediate weight bearing and five never offer immediate weight bearing. Seventeen surgeons provide weight bearing depending on the procedures performed: 17 surgeons allowed immediate weight bearing after labral resection, 10 after labral repair and 8 after labral reconstruction. Sixteen surgeons allow immediate weight bearing after psoas tenotomy. Twenty-one respondents restrict weight bearing after microfracture procedures for 3–8 weeks post-operatively. Return to running and impact sports were shorter for labral procedures and bony procedures and longer for cartilaginous and capsular procedures. Marked variability exists in the post-operative weight-bearing practices of hip arthroscopy surgeons. This study suggests that most surgeons allow immediate weight bearing as tolerated after labral resection, acetabular osteoplasty, chondroplasty and psoas tenotomy. For cartilage defect procedures, 6 weeks or more non-weight bearing is suggested depending on the area of the defect and lateral central edge angle. Delayed return to sports activities is suggested after microfracture procedures. The level of evidence was Level V expert opinions.