Miracle-dz/UniFAR-FTUs huggingface dataset:
OpenMPR: Recognize places using multimodal data for people with visual impairments

Place recognition plays a crucial role in navigational assistance, and is also a challenging issue in assistive technology. Place recognition is prone to erroneous localization owing to various changes between database and query images. Aiming at a wearable assistive device for visually impaired people, we propose an open-sourced place recognition algorithm, OpenMPR, which utilizes multimodal data to address the challenging issues of place recognition. Compared with conventional place recognition, the proposed OpenMPR not only leverages multiple effective descriptors, but also assigns different weights to those descriptors in image matching. Incorporating GNSS data into the algorithm, cone-based sequence searching is used for robust place recognition. The experiments illustrate that the proposed algorithm manages to solve the place recognition issue in real-world scenarios and surpasses state-of-the-art algorithms in terms of assistive navigation performance. On the real-world testing dataset, the online OpenMPR achieves 88.7% precision at 100% recall without illumination changes, and achieves 57.8% precision at 99.3% recall with illumination changes. The OpenMPR is available at https://github.com/chengricky/OpenMultiPR.
Leadership: Validation of a Self-Report Scale

The aim of this paper was to propose and test the factor structure of a new self-report questionnaire on leadership. A sample of 373 school principals in the Province of Quebec, Canada completed the initial 46-item version of the questionnaire. In order to obtain a questionnaire of minimal length, a four-step procedure was retained. First, items analysis was performed using Classical Test Theory. Second, Rasch analysis was used to identify non-fitting or overlapping items. Third, a confirmatory factor analysis (CFA) using structural equation modelling was performed on the 21 remaining items to verify the factor structure of the scale. Results show that the model with a single third-order dimension (leadership), two second-order dimensions (transactional and transformational leadership), and one first-order dimension (laissez-faire leadership) provides a good fit to the data. Finally, invariance of factor structure was assessed with a second sample of 222 vice-principals in the Province of Quebec, Canada. This model is in agreement with the theoretical model developed by Bass (1985), upon which the questionnaire is based.
Equity Tail Risk and Currency Risk Premia

We find that an option-based equity tail risk factor is priced in the cross section of currency returns. Currencies highly exposed to this factor offer a low risk premium because they hedge against equity tail risk. In a reduced-form model, we show that a long-short portfolio that buys currencies with high equity tail beta and shorts those with low tail beta extracts the global component embedded in the tail risk factor. Inspired by the model, we construct a novel global tail risk factor from currency returns. The estimated price of risk of this global factor is consistently negative and of similar magnitude in various currency portfolios including carry and momentum, suggesting that the excess returns of these strategies can be partially understood as compensations for global tail risk. <br>
Multi-Thread Based Design of Navigation Algorithm Module in Multi Radio Integrated Navigation System M&S Software

A multi-thread based navigation algorithm module is designed in a multi radio integrated navigation system modeling and simulation software in order to efficiently use resources in the software platform of the modeling and simulation software. By adopting the multi-thread architecture, features of navigation algorithms and concurrency of the algorisms can be easily included in the navigation algorithm module. In order to show the usefulness of the multi thread based navigation algorithm module design, a navigation algorithm module in the multi-radio integrated navigation system for GPS, KNSS, Loran-C, eLoran and DME/VOR is implemented in C++ under the Windows operating system. The implementation results show that the thread based design can be useful in the development of multi radio integrated navigation systems.
Structural investigation into the C‐terminal extension of the ene‐reductase from Ralstonia (Cupriavidus) metallidurans

Ene‐reductases (ERs), or Old Yellow Enzymes, catalyze the asymmetric reduction of various activated alkenes. This class of biocatalysts is considered an attractive alternative to current chemical technologies for hydrogenation due to their high selectivity and specificity. Here the X‐ray crystal structure of RmER, a “thermophilic”‐like ER from Ralstonia (Cupriavidus) metallidurans, is reported. Unlike other members of this class of ERs, RmER is monomeric in solution which we previously related to its atypical elongated C‐terminus. A typical dimer interface was however observed in our crystal structure, with the conserved Arg‐“finger” forming part of the adjacent monomer's active site and the elongated C‐terminus extending into the active site through contacting the “capping” domain. This dimerization also resulted in the loss of one FMN cofactor from each dimer pair. This potential transient dimerization and dissociation of FMN could conceivably explain the rapid rates previously observed when an FMN light‐driven cofactor regeneration system was used during catalysis with RmER.
Bounding the monomial index and (1, l)-weight choosability of a graph

Let G = (V,E) be a graph. For each e ∈E(G) and v ∈V(G), let Le and Lv, respectively, be a list of real numbers. Let w be a function on V(G) ∪E(G) such that w(e) ∈Le for each e ∈E(G) and w(v) ∈Lv for each v ∈V(G), and let cw be the vertex colouring obtained by cw(v) = w(v) + ∑ₑ ∋vw(e). A graph is (k,l)-weight choosable if there exists a weighting function w for which cw is proper whenever |Lv| ≥k and |Le| ≥l for every v ∈V(G) and e ∈E(G). A sufficient condition for a graph to be (1,l)-weight choosable was developed by Bartnicki, Grytczuk and Niwczyk (2009), based on the Combinatorial Nullstellensatz, a parameter which they call the monomial index of a graph, and matrix permanents. This paper extends their method to establish the first general upper bound on the monomial index of a graph, and thus to obtain an upper bound on l for which every admissible graph is (1,l)-weight choosable. Let ∂2(G) denote the smallest value s such that every induced subgraph of G has vertices at distance 2 whose degrees sum to at most s. We show that every admissible graph has monomial index at most ∂2(G) and hence that such graphs are (1, ∂2(G)+1)-weight choosable. While this does not improve the best known result on (1,l)-weight choosability, we show that the results can be extended to obtain improved bounds for some graph products; for instance, it is shown that G □ Kn is (1, nd+3)-weight choosable if G is d-degenerate.
Patellar Tendon Versus Hamstring Tendon Autografts for Reconstructing the Anterior Cruciate Ligament

Background The best means of ensuring knee stability after anterior cruciate ligament (ACL) reconstruction remains a core debate in sports medicine. Hypothesis There is no difference between ACL reconstruction with patellar tendon or hamstring tendon autografts with regard to postoperative knee laxity and instability. Study Design Meta-analysis of individual patient data. Methods Pooled analysis of individual patient data from 6 published randomized clinical trials included 423 patients with symptomatic unilateral anterior cruciate ligament injury randomly assigned to reconstruction with patellar tendon or hamstring tendon autograft. Knee instability, defined as a positive pivot-shift test result, was the primary outcome, and knee laxity, defined as a positive Lachman test result, was the secondary outcome. Odds ratios were computed before and after adjustment for potential confounders and trial effect. Regression analyses were performed to look for effects of covariates on outcomes, and mixed-effects models were used to account for a trial effect. Sensitivity analyses were conducted to explore the effects of missing data and excluding each trial. Results Anterior cruciate ligament reconstruction with patellar tendon autograft was significantly associated with a decreased risk of a positive pivot-shift test result (adjusted odds ratio, 0.46; 95% confidence interval, 0.24–0.86; P = .016). The risk of having a positive Lachman test result was not significantly different between the 2 groups. The estimated treatment effect was not substantially changed by differences in handling missing data or exclusion of any of the trials. A positive pivot-shift test result was more common in female (P = .003) and younger patients (P = .017). Conclusion Postoperative knee instability was less common after ACL reconstruction with patellar tendon autograft than with hamstring tendon autograft.
Manganese‐Enhanced Magnetic Resonance Imaging in Experimental Spinal Cord Injury: Correlation Between T1‐Weighted Changes and Mn2+ Concentrations

OBJECTIVEManganese (Mn2+)–enhanced magnetic resonance imaging (MEMRI) is a potentially important tool for assessing neural tissue regeneration after spinal cord injury (SCI). We evaluated the relation between Mn2+ and T1-weighted magnetic resonance (MR) signals in an SCI rat model. METHODSRats were divided into 4 groups with or without SCI (T9-level transection) and with or without Mn2+ injection. Two microliters of 0.2 mol/L MnCl2 was injected into the lateral ventricles. Magnetic resonance imaging (MRI) was performed 60 hours after injection. Signal intensities at cervical, thoracic, and lumbar levels were measured and normalized to the intensity of perivertebral muscles. Spinal cord sections were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) for total Mn2+ content. The results of ICP-MS were compared with MR signal intensity. RESULTST1-weighted MR signal intensity and ICP-MS–measured Mn2+ were significantly decreased below the SCI injury site in Mn2+-injected groups with or without SCI, and were similar to intensity and Mn2+ levels of noninjected animals. Signal intensity and Mn2+ concentration tended to decrease from cervical to lumbar spinal levels in the control rats. ICP-MS data correlated with MRI results. CONCLUSIONThe results confirmed Mn2+ uptake in the spinal cord after intraventricular injection. T1-weighted MR signal intensity correlates with spinal Mn2+ concentration as measured with ICP-MS. This work establishes the repeatability of MEMRI of the injured spinal cord and makes it possible to compare changes in axonal transport rates through the spinal cord after neuronal regeneration in vivo at different stages. MEMRI in animal models may improve understanding of the factors required to promote spinal cord regeneration.
StarFish: highly-available block storage

In this paper we present StarFish, a highly-available geographically-dispersed block storage system built from commodity servers running FreeBSD, which are connected by standard high-speed IP networking gear. StarFish achieves high availability by transparently replicating data over multiple storage sites. StarFish is accessed via a host-site appliance that masquerades as a host-attached storage device, hence it requires no special hardware or software in the host computer. We show that a StarFish system with 3 replicas and a write quorum size of 2 is a good choice, based on a formal analysis of data availability and reliability: 3 replicas with individual availability of 99%, a write quorum of 2, and read-only consistency gives better than 99.9999% data availability. Although StarFish increases the per-request latency relative to a direct-attached RAID, we show how to design a highly-available StarFish configuration that provides most of the performance of a direct-attached RAID on an I/O-intensive benchmark, even during the recovery of a failed replica. Moreover, the third replica may be connected by a link with long delays and limited bandwidth, which alleviates the necessity of dedicated communication links to all replicas.
Frequency domain analysis for dynamic nonlinearity measurement in A/D converters

The paper discusses the problem of measuring the dynamic systematic error, or the dynamic input-output characteristic, of an analog-to-digital converter simulated by a sinusoidal input. First of all, it is shown that the statistical methods, although widely used , yield misleading results in dynamic conditions, i.e., when the converter characteristics presents hysteresis. Secondly, the paper presents a modified version of a frequency-domain method (Chebyshev test), previously developed by the authors for testing static devices. Both simulation and experimental results show that the Chebyshev test for dynamic nonlinearities is a very fast way to measure the input-output characteristic of an ADC affected by hysteresis error.
Probing residues in the pore-forming (M2) domain of the Cys-loop receptor homologue GLIC reveals some unusual features

Abstract Cys-loop receptors play important roles in signal transduction. The Gloeobacter ligand-gated ion channel (GLIC) pore binds similar compounds to Cys-loop receptor pores, but has the advantage of known structures in open and closed states. GLIC is activated by protons with a pEC50 of 5.4, and has a histidine residue (His 11’) in its pore-forming α-helix (M2) which is involved in gating. Here we explore the role of this His and other M2 residues using two-electrode voltage clamp of mutant receptors expressed in oocytes. We show that 11’His is very sensitive to substitution; replacement with a range of amino acids ablates function. Similarly altering its location in M2 to the 8’, 9’, 10’, 12’, 13’ or 14’ positions ablated function. Most substitutions of Ser6’ or Ile9’ were also non-functional, although not Ile9’Leu and Ile9’Val. Unexpectedly, an Ile9’His substitution was constitutively active at pH 7, but closed as [H+] increased, with a pIC50 of 5.8. Substitution at 2’, 5’ and 7’ had little effect on pEC50. Overall the data show Ser6’ and His11’ are critical for the function of the receptor, and thus distinguish the roles of these M2 residues from those of Cys-loop receptors, where substitutions are mostly well tolerated. These data suggest modellers should be aware of these atypical features when using the GLIC pore as a model for Cys-loop receptor pores.
Alterations in Extracellular Matrix Composition in the Aging Larynx

Objective To study by immunohistochemistry the alterations of collagens I, III, IV, and V and elastin in the aging process of the human larynx. Study Design Cadaver study. Setting Universidade Estadual Paulista, Botucatu Medical School, São Paulo State University (UNESP), Brazil. Subjects and Methods Thirty vocal folds were obtained at autopsy from 10 adult men (aged 30 to 50 years) and 20 geriatric men (10 aged 60 to 75 years and 10 aged >75 years). Mid membranous vocal fold slides were subjected to immunohistochemical reactions. Digital imaging software (ImageJ) was used to quantify the increase in brownish staining of the lamina propria structures of vocal folds, from superficial to deep layers. Results There was an increase of collagen I and III immunoexpression in the elderly larynges, in both layers. Collagens IV and V were immunoexpressed in the vessels endothelium of the lamina propria and in the basement membrane. The immunoexpression of elastin decreased in the elderly larynges, in both lamina propria layers of the vocal folds. Conclusion A clear increase of collagens I and III and a decrease of elastic fibers were observed in the lamina propria of vocal folds. The concentration of collagens IV and V was the same across age groups. These findings suggest that as men age, the density of the extracellular matrix increases, brought about by an increase in collagen, while the loss of elastin results in decreased viscoelasticity.
Active transactions integrated with real-time transactions according to data freshness

Plants need both data acquisition without any loss and detection of state changes in restricted times. The paper proposes the active ring model for active real-time database systems which acquire data from industrial plants, provide the data for applications, and detect state changes to notify them to applications. The model incorporates the ECA mechanism into circular storage areas. In the ECA mechanism, conditions whose evaluation time is bounded are separated from others. The model is cognizant of data freshness. Since deadlines of transactions are set according to data freshness, the detection is integrated with the real-time acquisition. The paper includes an experimental result revealing that the active ring model is effective to provide service according to data freshness.
Coordinated Stabilization of a Multimachine Power System

The paper presents a sequential procedure for coordinated stabilization of a multimachine power system with arbitrary complexity of the system model. The most effective machine to be equipped with a power system stabilizer is identified using eigenvalue analysis. The selection is based on the sensitivity of critical eigenvalues to increases in the coefficient of a damping term which is inserted in each equation of motion, in succession. The method is applied to a three-machine system and simulation studies show appreciable improvements in the small disturbance stability of the system.
Very Low Resource Radio Browsing for Agile Developmental and Humanitarian Monitoring

We present a radio browsing system developed on a very small corpus of annotated speech by using semi-supervised training of multilingual DNN/HMM acoustic models. This system is intended to support relief and developmental programmes by the United Nations (UN) in parts of Africa where the spoken languages are extremely under resourced. We assume the availability of 12 minutes of annotated speech in the target language, and show how this can best be used to develop an acoustic model. First, a multilingual DNN/HMM is trained using Acholi as the target language and Luganda, Ugandan English and South African English as source languages. We show that the lowest word error rates are achieved by using this model to label further untranscribed target language data and then developing SGMM acoustic model from the extended dataset. The performance of an ASR system trained in this way is sufficient for keyword detection that yields useful and actionable near real-time information to developmental organisations.
Segmenting natural images with the least effort as humans

Given that natural image segmentation is well-known as an ill-posed problem, then how can we design an algorithm to obtain good performance as human subjects? A choice is to learn from human segmentations as MCG [3] which obtains the state-of-the-art performance and fairly high computational efficiency. Then a question arises here: what should we learn? The way all existing literatures exploit human segmentations ignores a basic fact that human segmentations are produced by human operations. The human segmentation process would inevitably fulfill the human behavior’s principles including the least effort principle (LEP): a human will strive to solve his problem in such a way as to minimize the total work that he must expend [1]. The principle gives us a new insight into our problem. Suppose you are a human subject in the BSDS segmentation experiment, and are required to segment images into pieces under the ending instruction: each piece contains only one single distinguished thing. Then your total effort F of segmenting an image should including understanding images (U) to guide following operations, and tracing boundaries (T ) by hands with a mouse: F (I,S) =U (I)+T (S). Then from the viewpoint of LEP, human subjects would like to find an acceptable segmentation S by minimizing their effort, or formally,
Identification of new LTO HVPSAW orientations considering finite thickness electrodes

The continuing trend towards higher operating frequencies in RF communications has strained SAW filter fabrication capabilities, focusing recent efforts on identifying low-attenuated high velocity pseudo-surface acoustic wave (HVPSAW) orientations of quartz, lithium niobate (LNO), lithium tantalate (LTO), and lithium tetraborate (LBO). In particular, LTO is a well-established SAW substrate widely used for wireless applications, due to its relatively high electromechanical coupling (K 2 ) and moderate temperature sensitivity in comparison to the other substrates previously mentioned. Although HVPSAW propagation directions have been recently identified in the literature for these materials, several show diminished coupling or prohibitively high propagation losses. Others imply the use of heavy mechanical loading by the use of thick electrodes to achieve reduced device loss. This paper reports on the investigation of LTO HVPSAW excitation and propagation properties, including: phase velocity, propagation loss per wavelength (λ), and electromechanical coupling for arbitrary orientations under periodic aluminum (Al), gold (Au), and platinum (Pt) electrodes of finite thickness h. The harmonic admittance (HA) of periodic electrodes is calculated using Chebyshev polynomial charge and stress basis functions in conjunction with finite element method using parallel computing techniques. The determination of well-defined complex poles in the HA curve as a function of crystal rotation leads to the identification of low-attenuated and highly coupled HVPSAW orientations. For example, along selected orientations of the LTO (0°, 120°, ψ) plane, HVPSAWs are identified which exhibit phase velocities (Vsc) around 5.0 km/s, propagation losses as low as 0.014 dB/λ, and K 2 as high as 6.997%, for Al, Au, and Pt electrodes with thicknesses around h/λ = 9%, h/λ = 3.25%, and h/λ = 3.5% respectively. For the same electrode materials and thicknesses, the HVPSAW propagating under uniform film layers show propagation losses around 0.3 dB/λ. Therefore, the resulting decrease in propagation loss by more than one order of magnitude demonstrates the importance of the grating structure in achieving low loss operational HVPSAW devices. The reported work identifies new LTO HVPSAW orientations, exhibiting high phase velocity, low propagation loss, and high electromechanical coupling, suitable for high frequency, low loss communication and sensor applications.
Computerized Medical Imaging and Graphics Digital pathology with Fourier ptychography

Fourier ptychographic microscopy (FPM) is a recently introduced method of acquiring high-resolution, wide ﬁeld of view (FOV) giga-pixel histology images. The FPM procedure ﬁrst acquires a sequence of low-resolution images of a sample under variable-angle illumination. It then combines these images using a novel phase retrieval algorithm to improve the employed microscope’s resolution beyond its conventional limit. Here, we ﬁrst describe how FPM’s resolution improvement can enhance wide FOV histology imaging. Second, we show that FPM also records a thin sample’s optical phase, which can help pathologists digitally extract as much information as possible from a given histology slide. © 2014 Elsevier Ltd. All rights reserved.