bluuebunny/crossref_metadata_2025 huggingface dataset:
Field emission characterization of in situ deposited gold nanocones with variable cone densities
Authors: Bieker Johannes , Roustaie Farough , Schlaak Helmut F. , Langer Christoph , Schreiner Rupert , Lotz Marcel , Wilfert Stefan
Published: January 2018

For the fabrication of field emitter cathodes with metallic nanocones, an in situ fabrication technique based on electrodeposition in an ion track etched polymer template was used. Three samples with nanocones made of gold and different cone densities were deposited on a circular electrode with a diameter of 2.5 mm, using templates with pore density of 6 × 104, 4 × 105, and 1 × 106 cones/cm2. The cones had a height of 24 μm, a base diameter between 3 and 3.75 μm, and a tip diameter below 500 nm. Integral field emission measurements revealed onset fields of down to 3.1 V/μm and average field enhancement factors of up to 1240. For one sample, the maximum emission current from the cathode reached 142.2 μA at an applied voltage of 338 V between cathode and extraction grid, which had a distance of 50 μm. To investigate the stability of the field emission current, cumulative long-term measurements were performed for over 50 h. A stable emission current of (31.0 ± 1.3) μA at an average applied voltage of 290 V (E = 5.8 V/μm) was observed. For currents above 100 μA, a decrease of the current and therefore a degradation of the emitter structures occurred.
Structure of the yeast oligosaccharyltransferase complex gives insight into eukaryotic N-glycosylation
Authors: Wild Rebekka , Kowal Julia , Eyring Jillianne , Ngwa Elsy M. , Aebi Markus , Locher Kaspar P.
Published: January 2018

Remember the sugar when making proteins

Eukaryotes have an elaborate trafficking and quality-control system for secreted glycoproteins. The glycosylation pathway begins in the endoplasmic reticulum with the enzyme oligosaccharyltransferase (OST), which attaches a long chain of sugars to asparagine residues of target proteins. Wild
et al.
report a cryo-electron microscopy structure of yeast OST, which includes eight separate membrane proteins. The central catalytic subunit contains binding sites for substrates and is flanked by accessory subunits that may facilitate delivery of newly translocated proteins for glycosylation.

Science
, this issue p.
545
Fifteen-minute consultation: Insulin pumps for type 1 diabetes in children and young people
Authors: Prentice Philippa , Elleri Daniela
Published: January 2018

There is increasing worldwide use of continuous subcutaneous insulin infusions in paediatric type 1 diabetes (T1D), reflecting recent research outcomes and guidance, as well as families’ wishes. Children/young people may present acutely with medical or surgical problems, in addition to issues related to T1D. This review provides general paediatricians with an introduction to pump therapy, highlighting common problems, management issues and when to seek specialist advice.
Surgical trauma induces overgrowth in lower limb gigantism: regulation with use of rapamycin is promising
Authors: Pinto Rohan Sebastian , Harrison William David , Graham Kenneth , Nayagam Durai
Published: January 2018

We describe an unclassified overgrowth syndrome characterised by unregulated growth of dermal fibroblasts in the lower limbs of a 35-year-old woman. APIK3CAgene mutation resulted in lower limb gigantism. Below the waist, she weighed 117 kg with each leg measuring over 100 cm in circumference. Her total adiposity was 50% accounted for by her legs mainly. Liposuction and surgical debulking were performed to reduce the size of the limbs but had exacerbated the overgrowth in her lower limbs. Systemic sepsis from an infected foot ulcer necessitated treatment by an above-knee amputation. Postoperatively, the stump increased in size by 19 kg. A trial of rapamycin to reverse the growth of the stump has shown promise. We discuss the clinical and genetic features of this previously unclassified disorder and the orthopaedic considerations involved.
Avoiding big bubble complications: outcomes of layer-by-layer deep anterior lamellar keratoplasty in children
Authors: Elbaz Uri , Kirwan Caitriona , Shen Carl , Ali Asim
Published: January 2018

Background/aims

To describe the visual and clinical outcomes of manual layer-by-layer deep anterior lamellar keratoplasty (DALK) in a paediatric population.

Methods

The charts of all children who underwent DALK surgery between January 2007 and January 2015 were reviewed retrospectively. Data collected included preoperative and postoperative spectacle-corrected distance visual acuity (CDVA), intraoperative and postoperative complications including graft rejection and failure. Residual posterior lamellar thickness (RPLT) and endothelial cell density (ECD) were measured in eyes with follow-up longer than 6 months.

Results

Fifty-one eyes of 42 patients were included in the study. The mean patient age at surgery was 11.2±5.2 years and the mean follow-up time was 36.5±23.7 months. The most common indications for surgery were mucopolysaccharidosis (29.4%) and keratoconus (23.5%). Nine eyes (17.6%) had intraoperative microperforation, none of which were converted to penetrating keratoplasty (PKP). Only one eye (2.0%) was converted to PKP. Five eyes (9.8%) had a stromal rejection episode of which one eye failed. Another four eyes (7.8%) experienced graft failure among which three eyes (75%) had infectious keratitis. Three of the five failed grafts had a successful repeat DALK. The average RPLT was 81.9±36.5μm. ECD was significantly lower in the operated eye compared with the normal eye (3096±333 cells/mm2vs 3376±342 cells/mm2, n=11, P=0.003). The mean postoperative CDVA was 0.5±0.4 logarithm of the minimum angle of resolution (logMAR) reflecting a gain of 0.3 logMAR (P<0.001).

Conclusion

Manual dissection DALK is a safe procedure in children with stromal opacities. Despite successful structural rehabilitation, functional recovery is still suboptimal mostly due to amblyopia.
Population-based assessment of visual acuity outcomes following cataract surgery in Australia: the National Eye Health Survey
Authors: Keel Stuart , Xie Jing , Foreman Joshua , Taylor Hugh R , Dirani Mohamed
Published: January 2018

Aim

To assess the visual outcomes of cataract surgery among a national sample of non-Indigenous and Indigenous Australians.

Methods

This was a population-based study of 3098 non-Indigenous Australians (50–98 years) and 1738 Indigenous Australians (40–92 years), stratified by remoteness. A poor postoperative outcome in an eye that had undergone cataract surgery was defined as presenting distance visual acuity (PVA) <6/12–6/60, and a very poor outcome was defined as PVA <6/60. Effective cataract surgery coverage (eCSC; operated cataract and a good outcome (PVA ≥6/12) as a proportion of operable plus operated cataract) was calculated.

Results

The sampling weight adjusted cataract surgery prevalence was 19.8% (95% CI 17.9 to 22.0) in non-Indigenous Australians and 8.2% (95% CI 6.0 to 9.6) in Indigenous Australians. Among the non-Indigenous population, poor and very poor PVA outcomes were present in 18.1% and 1.9% of eyes, respectively. For Indigenous Australians, these values were 27.8% and 6.3%, respectively. The main causes of poor vision were refractive error (non-Indigenous=41.8%; Indigenous=41.9%) and coincident disease (non-Indigenous=43.3%; Indigenous=40.3%). The eCSC rates in the non-Indigenous and Indigenous populations were 88.5% (95% CI 85.2 to 91.2) and 51.6% (95% CI 42.4 to 60.7), respectively.

Conclusion

Approximately half of eyes with a poor visual outcome postcataract surgery could be readily avoided through the appropriate refractive correction. The finding of a lower eCSC rate among Indigenous Australians suggests that improvements in access and quality of cataract services may be warranted in order to reduce cataract-related vision loss in the Indigenous population.
Model for predicting tensile strength of unsaturated cohesionless soils
Authors: Yin Penghai , Vanapalli Sai K.
Published: January 2018

The influence of tensile strength on the behaviour of cohesionless soils is typically ignored in geotechnical engineering practice. However, the tensile cracking and subsequent failure characteristics of earth structures, such as dams, slopes and embankments, are significantly influenced by the tensile strength. For this reason, a semi-empirical model is proposed for predicting the variation of the tensile strength of unsaturated cohesionless soils with the degree of saturation, using the soil-water characteristic curve (SWCC) as a tool. The proposed model is capable of predicting the tensile strength arising from matric suction and surface tension, which are related to saturated pores and to the air–water interface associated with water bridges around interparticle contacts in unsaturated pores, respectively. Information about (i) the matric suction (ua– uw), the capillary degree of saturation (Sc), and the residual degree of saturation (Sr) derived from the SWCC; (ii) the mean particle size (d50) and the coefficient of uniformity (Cu) from the grain-size distribution curve; (iii) the void ratio (e); and (iv) the friction angle ([Formula: see text]) at low normal stress level is required to employ this model. The proposed model is validated by comparing the prediction results with measured tensile strength of 10 different unsaturated cohesionless soils (including five sandy soils and five silty soils). The proposed model is promising for use in engineering practice applications as it only requires conventional soil properties, alleviating the need for cumbersome experimental studies for the determination of tensile strength of unsaturated cohesionless soils.
Evidence for nonpathogenic relationships ofAlternariasectionUndifilumendophytes within three host locoweed plant species
Authors: Noor Aziza Ibrahim , Nava Amy , Cooke Peter , Cook Daniel , Creamer Rebecca
Published: January 2018

Locoweeds are legumes of the Astragalus and Oxytropis genera that live symbiotically with the fungal endosymbionts belonging to Alternaria section Undifilum. These endophytes produce the toxin swainsonine, which causes a neurological syndrome (locosim) when the plant is ingested by grazing animals. Here we characterize the growth of the endophytes within plant tissues using confocal and scanning electron microscopy (SEM) to define the physical relationship. Microscopy results revealed the endophyte distribution to be densely networked, with the mycelia aligned parallel to the long axis of the plant stem and with no pathology to plant cell walls, xylem, or phloem. The autofluorescent mycelia were located intercellulary in the pith of stems. Stereofluoroscope observations of Alternaria oxytropis, A. cinerea, and A. fulva in phytoagar showed that mycelial growth occurred at the tip of hyphae. The growth rate of A. cinerea was significantly faster than for A. oxytropis or A. fulva. All three species of endophytes grew significantly faster at 3 days age of culture and grew slowly or not at all after 20 or 30 days. Analyses of the growth of these fungi support the hypothesis that there is a nonpathogenic symbiosis between the fungal endophytes and their host plants.
A new multifactorial approach for studying intra-annual secondary growth dynamics in Mediterranean mixed forests: integrating biotic and abiotic interactions
Authors: de-Dios-García Javier , Manso Rubén , Calama Rafael , Fortin Mathieu , Pardos Marta
Published: January 2018

Studying intra-annual growth dynamics through a modelling approach has proved useful for characterizing differences in wood phenology between species and deviations from the expected tree growth due to climate change. The aim of this paper was to determine the climatic factors and the inter- and intra-specific competition traits that drive intra-annual secondary growth dynamics in three Mediterranean tree species that naturally co-exist in the Spanish Northern Plateau (Pinus pinea L., Juniperus thurifera L., and Quercus ilex subsp. ballota (Desf.) Samp.). For this purpose, we obtained girth increment data from band dendrometers installed on 58 trees from May 2012 to April 2015. Half of them were located in a high-density plot and half were in a low-density plot. These data were analysed through a nonlinear multifactorial model considering daily and cumulative climatic effects together with inter- and intra-specific competition indices. Our results provide evidence of a spatiotemporal niche separation between species. Compared with other species, Q. ilex subsp. ballota showed a wider thermal amplitude, a higher mean optimum temperature for growth, and a milder effect of drought on its secondary growth. Under current climate change projections, simulations based on our model predict a secondary growth reduction for P. pinea and a growth enhancement for Q. ilex subsp. ballota in these Mediterranean mixtures.
Botany, Phytochemistry, Pharmacology and Toxicity of Strychnos nux-vomica L.: A Review
Authors: Guo Rixin , Wang Ting , Zhou Guohong , Xu Mengying , Yu Xiankuo , Zhang Xiao , Sui Feng , Li Chun , Tang Liying , Wang Zhuju
Published: January 2018

Strychnos nux-vomica L. belongs to the genus Strychnos of the family Loganiaceae and grows in Sri Lanka, India and Australia. The traditional medicinal component is its seed, called Nux vomica. This study provides a relevant and comprehensive review of S. nux-vomica L., including its botany, ethnopharmacology, phytochemistry, pharmacology and toxicology, thus providing a foundation for future studies. Up to the present day, over 84 compounds, including alkaloids, iridoid glycosides, flavonoid glycosides, triterpenoids, steroids and organic acids, among others, have been isolated and identified from S. nux-vomica. These compounds possess an array of biological activities, including effects on the nervous system, analgesic and anti-inflammatory actions, antitumor effects, inhibition of the growth of pathogenic microorganisms and regulation of immune function. Furthermore, toxicity and detoxification methods are preliminarily discussed toward the end of this review. In further research on S. nux-vomica, bioactivity-guided isolation strategies should be emphasized. Its antitumor effects should be investigated further and in vivo animal experiments should be performed alongside in vitro testing. The pharmacological activity and toxicology of strychnine [Formula: see text]-oxide and brucine [Formula: see text]-oxide should be studied to explore the detoxification mechanism associated with processing more deeply.
Andrographolide Inhibits Oxidized LDL-Induced Cholesterol Accumulation and Foam Cell Formation in Macrophages
Authors: Lin Hung-Chih , Lii Chong-Kuei , Chen Hui-Chun , Lin Ai-Hsuan , Yang Ya-Chen , Chen Haw-Wen
Published: January 2018

oxLDL is involved in the pathogenesis of atherosclerotic lesions through cholesterol accumulation in macrophage foam cells. Andrographolide, the bioactive component of Andrographis paniculata, possesses several biological activities such as anti-inflammatory, anti-oxidant, and anticancer functions. Scavenger receptors (SRs), including class A SR (SR-A) and CD36, are responsible for the internalization of oxLDL. In contrast, receptors for reverse cholesterol transport, including ABCA1 and ABCG1, mediate the efflux of cholesterol from macrophage foam cells. Transcription factor liver X receptor [Formula: see text] (LXR[Formula: see text] plays a key role in lipid metabolism and inflammation as well as in the regulation of ABCA1 and ABCG1 expression. Because of the contribution of inflammation to macrophage foam cell formation and the potent anti-inflammatory activity of andrographolide, we hypothesized that andrographolide might inhibit oxLDL-induced macrophage foam cell formation. The results showed that andrographolide reduced oxLDL-induced lipid accumulation in macrophage foam cells. Andrographolide decreased the mRNA and protein expression of CD36 by inducing the degradation of CD36 mRNA; however, andrographolide had no effect on SR-A expression. In contrast, andrographolide increased the mRNA and protein expression of ABCA1 and ABCG1, which were dependent on LXR[Formula: see text]. Andrographolide enhanced LXR[Formula: see text] nuclear translocation and DNA binding activity. Treatment with the LXR[Formula: see text] antagonist GGPP and transfection with LXR[Formula: see text] siRNA reversed the ability of andrographolide to stimulate ABCA1 and ABCG1 protein expression. In conclusion, inhibition of CD36-mediated oxLDL uptake and induction of ABCA1- and ABCG1-dependent cholesterol efflux are two working mechanisms by which andrographolide inhibits macrophage foam cell formation, which suggests that andrographolide could be a potential candidate to prevent atherosclerosis.
Protective Effect of Safflower Seed on Cisplatin-Induced Renal Damage in Mice via Oxidative Stress and Apoptosis-Mediated Pathways
Authors: Park Chan Hum , Lee Ah Young , Kim Ji Hyun , Seong Su Hui , Jang Gwi Yeong , Cho Eun Ju , Choi Jae Sue , Kwon Jungkee , Kim Young Ock , Lee Sang Won , Yokozawa Takako , Shin Yu Su
Published: January 2018

Cisplatin, a platinum chelate with potent antitumor activity against cancers of the testis, ovary, urinary bladder, prostate, and head and neck, has adverse effects on the kidney, bone marrow, and digestive organs, and its use is particularly limited by nephropathy as a side effect. In the present study, safflower seed extract was administered to a mouse model of cisplatin-induced acute renal failure to investigate its activity. Cisplatin (20[Formula: see text]mg/kg body weight) was administered by intraperitoneal injection to mice that had received oral safflower seed extract (100 or 200[Formula: see text]mg/kg body weight per day) for the preceding 2 days. Three days after the cisplatin injection, serum and renal biochemical factors; oxidative stress, inflammation, and apoptosis-related protein expression; and histological findings were evaluated. Cisplatin-treated control mice showed body-weight, food intake and water intake loss, and increased kidney weight, whereas the administration of safflower seed extract attenuated these effects ([Formula: see text], [Formula: see text]). Moreover, safflower seed extract significantly decreased the renal functional parameters urea nitrogen and creatinine in the serum ([Formula: see text] and [Formula: see text], respectively). Safflower seed extract also significantly reduced the enhanced levels of reactive oxygen species in the kidney observed following cisplatin treatment, with significance. The expression of proteins related to the anti-oxidant defense system in the kidney was down-regulated following cisplatin treatment, but safflower seed extract significantly up-regulated the expression of the anti-oxidant enzyme catalase. Furthermore, safflower seed extract reduced the overexpression of phosphor (p)-p38, nuclear factor-kappa B p65, cyclooxygenase-2, inducible nitric oxide synthase, ATR, p-p53, Bax, and caspase 3 proteins, and mice treated with safflower seed extract exhibited less renal histological damage. These results provide important evidence that safflower seed extract exerts a pleiotropic effect on several oxidative stress- and apoptosis-related parameters and has a renoprotective effect in cisplatin-treated mice.
Probing plasmon resonances of individual aluminum nanoparticles
Authors: Wei Zhongxia , Mao Peng , Cao Lu , Song Fengqi
Published: January 2018

The plasmon resonances of individual aluminum nanoparticles are investigated by electron energy-loss spectroscopy (EELS) in scanning transmission electron microscope (STEM). Surface plasmon mode and bulk plasmon mode of Al nanoparticles are clearly characterized in the EEL spectra. Discrete dipole approximation (DDA) calculations show that as the particle diameter increases from 20 nm to 100 nm, the plasmon resonance shifts to lower energy and higher mode of surface plasmon arises when the diameter reaches 60 nm and larger.
Plasma polymerized hexamethyldisiloxane thin films for corrosion protection
Authors: Saloum S. , Alkhaled B. , Alsadat W. , Kakhia M. , Shaker S. A.
Published: January 2018

This study focused on the corrosion protection performance of plasma polymerized HMDSO thin films in two different corrosive medias, 0.3M NaCl and 0.3M H2SO4. The pp-HMDSO thin films were deposited on steel substrates for electrochemical tests using the potentiodynamic polarization technique, they were deposited also on aluminum and silicon substrates to investigate their resistance to corrosion, through the analysis of the degradation of microhardness and morphology, respectively, after immersion of the substrates for one week in the corrosive media. The results showed promising corrosion protection properties of the pp-HMDSO thin films.
Sound absorption of a new oblique-section acoustic metamaterial with nested resonator
Authors: Gao Nansha , Hou Hong , Zhang Yanni , Wu Jiu Hui
Published: January 2018

This study designs and investigates high-efficiency sound absorption of new oblique-section nested resonators. Impedance tube experiment results show that different combinations of oblique-section nest resonators have tunable low-frequency bandwidth characteristics. The sound absorption mechanism is due to air friction losses in the slotted region and the sample structure resonance. The acousto-electric analogy model demonstrates that the sound absorption peak and bandwidth can be modulated over an even wider frequency range by changing the geometric size and combinations of structures. The proposed structure can be easily fabricated and used in low-frequency sound absorption applications.
Effects of (Mo/W, N) codoping on electronic structures of NaNbO3 based on hybrid density functional calculations
Authors: Shi Haifeng , Lu Mengfei , Lan Benyue , Zhang Chengliang
Published: January 2018

The influences of a series of (N, Mo, W) monodoping and N–Mo(W) codoping on the electronic structures of sodium niobate have been systematically investigated by density functional theory (DFT) calculations with the hybrid B3LYP functional. The results indicated that some localized N 2p states were formed above the top of valence band (VB) after N-doping. In the case of Mo(W)-doping, the position of VB shifted up, meanwhile, the hybridization of Nb 4d and Mo 4d(W 5d) states moved the conduction band (CB) downward, leading to narrowing the band gap. As for N–Mo codoped NaNbO3, the localized Mo 4d states were formed near the bottom of CB while the localized N 2p states appeared above the top of VB. When N–W codoping, the W 5d p states mixed with Nb 4d states and then moved the top of CB downward as well as some localized N 2p states were formed above the valence band (O 2p), leading to the obvious reduction of the photon transition energy compared with that of NaNbO3.
Multispectral face spoofing detection using VIS–NIR imaging correlation
Authors: Sun Xudong , Huang Lei , Liu Changping
Published: January 2018

With the wide applications of face recognition techniques, spoofing detection is playing an important role in the security systems and has drawn much attention. This research presents a multispectral face anti-spoofing method working with both visible (VIS) and near-infrared (NIR) spectra imaging, which exploits VIS–NIR image consistency for spoofing detection. First, we use part-based methods to extract illumination robust local descriptors, and then the consistency is calculated to perform spoofing detection. In order to further exploit multispectral correlation in local patches and to be free from manually chosen regions, we learn a confidence factor map for all the patches, which is used in final classifier. Experimental results of self-collected datasets, public Msspoof and PolyU-HSFD datasets show that the proposed approach gains promising results for both intra-dataset and cross-dataset testing scenarios, and that our method can deal with different illumination and both photo and screen spoofing.
Multi-pose 3D facial texture refinement for face recognition
Authors: Gao Wanshun , Zhao Xi , An Jun , Zou Jianhua
Published: January 2018

In this paper, we propose a novel approach for 3D face reconstruction from multi-facial images. Given original pose-variant images, coarse 3D face templates are initialized to reconstruct a refined 3D face mesh in an iteration manner. Then, we warp original facial images to the 2D meshes projected from 3D using Sparse Mesh Affine Warp (SMAW). Finally, we weight the face patches in each view respectively and map the patch with higher weight to a canonical UV space. For facial images with arbitrary pose, their invisible regions are filled with the corresponding UV patches. Poisson editing is applied to blend different patches seamlessly. We evaluate the proposed method on LFW dataset in terms of texture refinement and face recognition. The results demonstrate competitive performance compared to state-of-the-art methods.
Wick–Tzitzeica solitons and their Monge–Ampér equation
Authors: Crasmareanu Mircea , Pişcoran Laurian-Ioan
Published: January 2018

We apply the Wick rotation to the Monge–Ampère equation of Tzitzeica graphs and we introduce the Wick–Tzitzeica solitons as complex functions solving the new equation. Some known Tzitzeica surfaces yields examples of these new solitons and we analyze them. To a second Wick–Tzitzeica soliton, we associate a homogeneous ODE system of gradient type which is Nambu–Poisson.
Dynamic task partition for video decoding on heterogeneous dual-core platforms
Authors: Tsai Chun-Jen , Shen Tsung-Fan , Liao Pei-Ching
Published: January 2018

This article presents the design of a video decoder using dynamic task partition approach on a heterogeneous dual-core embedded platform. For such systems, static task partition between the two cores at design time is a typical approach for application development. In this article, we propose a runtime dynamic task partition model and implement an MPEG-4 Simple Profile video decoder using this approach on a TI OMAP 5912 platform. Comparing with a traditional mobile video decoder optimized for the same DSP core, the performance gain from dynamic task partition is 38.4% on average. More importantly, the gain is achieved with the design constraint that the implementation effort for the dynamic task partition decoder is about the same as the effort using design-time task partition model. Unlike common belief that the inter-processor communication overhead would be too high to justify intense cooperation between two heterogeneous cores, this paper shows that it is indeed beneficial to adopt dynamic task partition model on commercially available heterogeneous multi-core platforms.
Moths
Authors: Misler Matthew , Jerger Natalie Enright
Published: January 2018

As the number of cores integrated on a single chip continues to increase, communication has the potential to become a severe bottleneck to overall system performance. The presence of thread sharing and the distribution of data across cache banks on the chip can result in longdistance communication. Long-distance communication incurs substantial latency that impacts performance; furthermore, this communication consumes significant dynamic power when packets are switched over many Network-on-Chip (NoC) links and routers. Thread migration can mitigate problems created by long distance communication. This article presents Moths, an efficient runtime algorithm that responds automatically to dynamic NoC traffic patterns, providing beneficial thread migration to decrease overall traffic volume and average packet latency. Moths reduces on-chip network latency by up to 28.4% (18.0% on average) and traffic volume by up to 24.9% (20.6% on average) across a variety of commercial and scientific benchmarks.
HERMES
Authors: Noshadi Hyduke , Dabiri Foad , Ahmadian Shaun , Amini Navid , Sarrafzadeh Majid
Published: January 2018

We introduce
Hermes
, a lightweight smart shoe and its supporting infrastructure aimed at extending gait and instability analysis and human instability/balance monitoring outside of a laboratory environment. We aimed to create a scientific tool capable of high-level measures, by combining embedded sensing, signal processing and modeling techniques.
Hermes
monitors walking behavior and uses an instability assessment model to generate quantitative value with episodes of activity identified by physician, researchers or investigators as important. The underlying instability assessment model incorporates variability and correlation of features extracted during ambulation that have been identified by geriatric motion study experts as precursor to instability, balance abnormality and possible fall risk.
Hermes
provides a mobile, affordable and long-term instability analysis and detection system that is customizable to individual users, and is context-aware, with the capability of being guided by experts. Our experiments demonstrate the feasibility of our model and the complimentary role our system can play by providing long-term monitoring of patients outside a hospital or clinical setting at a reduced cost, with greater user convenience, compliance and inference capabilities that meet the physician's or investigator's needs.
Security challenges in embedded systems
Authors: Serpanos Dimitrios N. , Voyiatzis Artemios G.
Published: January 2018

Embedded systems security is a significant requirement in emerging environments, considering the increasing deployment of embedded systems in several application domains. The large number of deployed embedded systems, their limited resources and their increasing complexity render systems vulnerable to an increasing number of threats. Additionally, the involvement of sensitive, often private, information and the expectation for safe and dependable embedded platforms lead to strong security requirements, even legal ones, which require new technologies for their provision. In this article, we provide an overview of embedded security issues, used methods and technologies, identifying important challenges in this emerging field.
On Learning How Players Learn
Authors: Krichene Walid , Bourguiba Mohamed Chedhli , Tlam Kiet , Bayen Alexandre
Published: January 2018

The routing game models congestion in transportation networks, communication networks, and other cyber-physical systems in which agents compete for shared resources. We consider an online learning model of player dynamics: at each iteration, every player chooses a route (or a probability distribution over routes, which corresponds to a flow allocation over the physical network), then the joint decision of all players determines the costs of each path, which are then revealed to the players.

We pose the following estimation problem: given a sequence of player decisions and the corresponding costs, we would like to estimate the parameters of the learning model. We consider, in particular, entropic mirror descent dynamics and reduce the problem to estimating the learning rates of each player.

In order to demonstrate our methods, we developed a web application that allows players to participate in a distributed, online routing game, and we deployed the application on Amazon Mechanical Turk. When players log in, they are assigned an origin and destination on a shared network. They can choose, at each iteration, a distribution over their available routes, and each player seeks to minimize her own cost. We collect a dataset using this platform, then apply the proposed method to estimate the learning rates of each player. We observe, in particular, that after an exploration phase, the joint decision of the players remains within a small distance of the set of equilibria. We also use the estimated model parameters to predict the flow distribution over routes, and compare our predictions to the actual distributions, showing that the online learning model can be used as a predictive model over short horizons. Finally, we discuss some of the qualitative insights from the experiments, and give directions for future research.
Numerical Bifurcation Analysis of Homoclinic Orbits Embedded in One-Dimensional Manifolds of Maps
Authors: Neirynck Niels , Govaerts Willy , Kuznetsov Yuri A. , Meijer Hil G. E.
Published: January 2018

We describe new methods for initializing the computation of homoclinic orbits for maps in a state space with arbitrary dimension and for detecting their bifurcations. The initialization methods build on known and improved methods for computing one-dimensional stable and unstable manifolds. The methods are implemented in M
at
C
ont
M, a freely available toolbox in Matlab for numerical analysis of bifurcations of fixed points, periodic orbits, and connecting orbits of smooth nonlinear maps. The bifurcation analysis of homoclinic connections under variation of one parameter is based on continuation methods and allows us to detect all known codimension 1 and 2 bifurcations in three-dimensional (3D) maps, including tangencies and generalized tangencies. M
at
C
ont
M provides a graphical user interface, enabling interactive control for all computations. As the prime new feature, we discuss an algorithm for initializing connecting orbits in the important special case where either the stable or unstable manifold is one-dimensional, allowing us to compute all homoclinic orbits to saddle points in 3D maps. We illustrate this algorithm in the study of the adaptive control map, a 3D map introduced in 1991 by Frouzakis, Adomaitis, and Kevrekidis, to obtain a rather complete bifurcation diagram of the resonance horn in a 1:5 Neimark-Sacker bifurcation point, revealing new features.
Analysis and Classification of Shape-Changing Interfaces for Design and Application-based Research
Authors: Sturdee Miriam , Alexander Jason
Published: January 2018

Shape-changing interfaces are physically tangible, interactive devices, surfaces, or spaces that allow for rich, organic, and novel experiences with computational devices. Over the last 15 years, research has produced functional prototypes over many use applications; reviews have identified themes and possible future directions but have not yet looked at possible design or application-based research. Here, we gather this information together to provide a reference for designers and researchers wishing to build upon existing prototyping work, using synthesis and discussion of existing shape-changing interface reviews and comprehensive analysis and classification of 84 shape-changing interfaces. Eight categories of prototype are identified alongside recommendations for the field.
Robust Multi-Variate Temporal Features of Multi-Variate Time Series
Authors: Liu Sicong , Poccia Silvestro Roberto , Candan K. Selçuk , Sapino Maria Luisa , Wang Xiaolan
Published: January 2018

Many applications generate and/or consume multi-variate temporal data, and experts often lack the means to adequately and systematically search for and interpret multi-variate observations. In this article, we first observe that multi-variate time series often carry localized multi-variate temporal features that are robust against noise. We then argue that these multi-variate temporal features can be extracted by simultaneously considering, at multiple scales, temporal characteristics of the time series
along with external knowledge
, including variate relationships that are known a priori. Relying on these observations, we develop data models and algorithms to detect
robust multi-variate temporal
(RMT) features that can be indexed for efficient and accurate retrieval and can be used for supporting data exploration and analysis tasks. Experiments confirm that the proposed RMT algorithm is highly effective and efficient in identifying
robust
multi-scale temporal features of multi-variate time series.
Linear Time Parameterized Algorithms for S
ubset
F
eedback
V
ertex
S
et
Authors: Lokshtanov Daniel , Ramanujan M. S. , Saurabh Saket
Published: January 2018

In the S
ubset
F
eedback
V
ertex
S
et
(S
ubset
FVS) problem, the input is a graph
G
on
n
vertices and
m
edges, a subset of vertices
T
, referred to as terminals, and an integer
k
. The objective is to determine whether there exists a set of at most
k
vertices intersecting every cycle that contains a terminal. The study of parameterized algorithms for this generalization of the F
eedback
V
ertex
S
et
problem has received significant attention over the past few years. In fact, the parameterized complexity of this problem was open until 2011, when two groups independently showed that the problem is fixed parameter tractable. Using tools from graph minors,, Kawarabayashi and Kobayashi obtained an algorithm for S
ubset
FVS running in time
O
(
f
(
k
)ċ
n
2
m
) [SODA 2012, JCTB 2012]. Independently, Cygan et al. [ICALP 2011, SIDMA 2013] designed an algorithm for S
ubset
FVS running in time 2

O
(
k
log
k
)

ċ
n

O
(1)

. More recently, Wahlström obtained the first single exponential time algorithm for S
ubset
FVS, running in time 4

k

ċ
n

O
(1)

[SODA 2014]. While the 2

O
(
k
)

dependence on the parameter
k
is optimal under the Exponential Time Hypothesis, the dependence of this algorithm as well as those preceding it, on the input size is at least quadratic. In this article, we design the first linear time parameterized algorithms for S
ubset
FVS. More precisely, we obtain the following new algorithms for S
ubset
FVS.

— A randomized algorithm for S
ubset
FVS running in time
O
(25.6

k

ċ (
n
+
m
)).

— A deterministic algorithm for S
ubset
FVS running in time 2
O
(
k
log
k
) ċ (
n
+
m
).

Since it is known that assuming the Exponential Time Hypothesis, S
ubset
FVS cannot have an algorithm running in time 2

o
(
k
)

n

O
(1)

, our first algorithm obtains the best possible asymptotic dependence on both the parameter as well as the input size. Both of our algorithms are based on “cut centrality,” in the sense that solution vertices are likely to show up in minimum size cuts between vertices sampled from carefully chosen distributions.
Efficient Parallel Random Sampling—Vectorized, Cache-Efficient, and Online
Authors: Sanders Peter , Lamm Sebastian , Hübschle-Schneider Lorenz , Schrade Emanuel , Dachsbacher Carsten
Published: January 2018

We consider the problem of sampling
n
numbers from the range { 1,… ,
N
} without replacement on modern architectures. The main result is a simple divide-and-conquer scheme that makes sequential algorithms more cache efficient and leads to a parallel algorithm running in expected time
O
(
n
/
p
+log
p
) on
p
processors, i.e., scales to massively parallel machines even for moderate values of
n
. The amount of communication between the processors is very small (at most
O
(log
p
)) and independent of the sample size. We also discuss modifications needed for load balancing, online sampling, sampling with replacement, Bernoulli sampling, and vectorization on SIMD units or GPUs.
Robust Privacy-Preserving Image Sharing over Online Social Networks (OSNs)
Authors: Sun Weiwei , Zhou Jiantao , Zhu Shuyuan , Tang Yuan Yan
Published: January 2018

Sharing images online has become extremely easy and popular due to the ever-increasing adoption of mobile devices and online social networks (OSNs). The privacy issues arising from image sharing over OSNs have received significant attention in recent years. In this article, we consider the problem of designing a secure, robust, high-fidelity, storage-efficient image-sharing scheme over Facebook, a representative OSN that is widely accessed. To accomplish this goal, we first conduct an in-depth investigation on the manipulations that Facebook performs to the uploaded images. Assisted by such knowledge, we propose a DCT-domain image encryption/decryption framework that is robust against these lossy operations. As verified theoretically and experimentally, superior performance in terms of data privacy, quality of the reconstructed images, and storage cost can be achieved.
The polyhedra library in m
aple
Authors: Jing Rui-Juan , Maza Marc Moreno
Published: January 2018

The Polyhedra library is dedicated to solving problems dealing with the integer points of polyhedral sets. Such problems include decomposing the integer points of such sets, solving parametric integer programs, performing dependence analysis in for-loop nests and determining the validity of certain Presburger formulas.
Programming support for time-sensitive adaptation in cyberphysical systems
Authors: Afanasov Mikhail , Iavorskii Aleksandr , Mottola Luca
Published: January 2018

Cyberphysical systems (CPS) integrate embedded sensors, actuators, and computing elements for controlling physical processes. Due to the intimate interactions with the surrounding environment, CPS software must continuously adapt to changing conditions. Enacting adaptation decisions is often subject to strict time requirements to ensure control stability, while CPS software must operate within the tight resource constraints that characterize CPS platforms. Developers are typically left without dedicated programming support to cope with these aspects. This results in either to neglect functional or timing issues that may potentially arise or to invest significant efforts to implement hand-crafted solutions. We provide programming constructs that allow developers to simplify the specification of adaptive processing and to rely on well-defined time semantics. Our evaluation shows that using these constructs simplifies implementations while reducing developers' effort, at the price of a modest memory and processing overhead.
FLOPSYNC-QACS
Authors: Terraneo Federico , Papadopoulos Alessandro Vittorio , Leva Alberto , Prandini Maria
Published: January 2018

The development of distributed real-time systems often relies on clock synchronization. However, achieving precise synchronization in the field of Wireless Sensor Networks (WSNs) is hampered by competing design challenges, such as energy consumption and cost constraints, e.g., in Internet of Things applications. For these reasons many WSN hardware platforms rely on a low frequency clock crystal to provide the local timebase. Although this solution is inexpensive and allows for a remarkably low energy consumption, it limits the resolution at which time can be measured. The FLOPSYNC synchronization scheme provides low-energy synchronization that takes into account the quartz crystal imperfections. The main limitation of the approach are the effects of quantization.

In this paper we propose a clock synchronization scheme that explicitly takes into account quantization effects caused by low frequency clock crystal, thus addressing the clock synchronization issue in cost-sensitive WSN node platforms. The solution adopts switched control for minimizing the effect of quantization, with minimal overhead. We provide experimental evidence that the approach manages to reach a synchronization error of at most 1 clock tick in a real WSN.
DTFM
Authors: Dridi Mourad , Rubini Stéphane , Singhoff Frank , Diguet Jean-Philippe
Published: January 2018

Many-core processors are expected to be hardware targets to support the execution of real-time applications. In a many-core processor, cores communicate through a Network-On-Chip (NoC), which offers high bandwidth and scalability, but also introduces contentions leading to additional variability to task execution times. Such contentions also strongly increase the pessimistic trend of worst case execution time estimation. Consequently, modeling and analysis of network contentions interferences on many-core processors is a challenge to support real-time applications. In this article, we formalize a dual task and flow model called DTFM. From the specification of a real-time application composed of a set of tasks and their communication dependencies, DTFM allows us to compute flow requirements and to assess predictability of the tasks. DTFM is extensible enough to be adapted to various NoCs and task models, allowing designers to compare candidate software and NoC architectures. Furthermore, we introduce an original validation approach based on the cross-use of a task level real-time scheduling analysis tool and a cycle-accurate SystemC NoC simulator.
Psychology, Science, and Knowledge Construction: Broadening Perspectives from the Replication Crisis
Authors: Shrout Patrick E. , Rodgers Joseph L.
Published: January 2018

Psychology advances knowledge by testing statistical hypotheses using empirical observations and data. The expectation is that most statistically significant findings can be replicated in new data and in new laboratories, but in practice many findings have replicated less often than expected, leading to claims of a replication crisis. We review recent methodological literature on questionable research practices, meta-analysis, and power analysis to explain the apparently high rates of failure to replicate. Psychologists can improve research practices to advance knowledge in ways that improve replicability. We recommend that researchers adopt open science conventions of preregi-stration and full disclosure and that replication efforts be based on multiple studies rather than on a single replication attempt. We call for more sophisticated power analyses, careful consideration of the various influences on effect sizes, and more complete disclosure of nonsignificant as well as statistically significant findings.
Quantitative characterization of glomerular fibrosis with magnetic resonance imaging: a feasibility study in a rat glomerulonephritis model
Authors: Conlin Christopher C. , Huang Yufeng , Gordon Brian Adam Jamison , Zhang Jeff L.
Published: January 2018

Glomerular fibrosis occurs in the early stages of multiple renal diseases, including hypertensive and diabetic nephropathy. Conventional assessment of glomerular fibrosis relies on kidney biopsy, which is invasive and does not reflect physiological aspects such as blood perfusion. In this study, we sought to assess potential changes of cortical perfusion and microstructure at different degrees of glomerular fibrosis using magnetic resonance imaging (MRI). A rat model of glomerular fibrosis was induced by injecting anti-Thy-1 monoclonal antibody OX-7 to promote mesangial extracellular matrix proliferation. For six rats on day 5 and five rats on day 12 after the induction, we measured renal cortical perfusion and spin-spin relaxation time (T2) in a 3-Tesla MRI scanner. T2 reflects tissue microstructural changes. Glomerular fibrosis severity was evaluated by histological analysis and proteinuria. Four rats without fibrosis were included as controls. In the control rats, the periodic acid-Schiff (PAS)-positive area was 22 ± 1% of total glomerular tuft, which increased significantly to 56 ± 12% and 45 ± 10% in the day 5 and day 12 fibrotic groups, respectively ( P < 0.01). For the three groups (control, day 5, and day 12 after OX-7 injection), cortical perfusion was 7.27 ± 2.54, 3.78 ± 2.17, and 3.32 ± 2.62 ml·min−1·g−1, respectively, decreasing with fibrosis severity ( P < 0.01), and cortical T2 was 75.2 ± 4.6, 84.1 ± 3.0, and 87.9 ± 5.6 ms, respectively ( P < 0.01). In conclusion, extracellular matrix proliferation in glomerular mesangial cells severely diminished blood flow through the glomeruli and also altered cortical microstructure to increase cortical T2. The MRI-measured parameters are proven to be sensitive markers for characterizing glomerular fibrosis.