199 research outputs found

    Forward optic flow is prioritised in visual awareness independently of walking direction

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    When two different images are presented separately to each eye, one experiences smooth transitions between them-a phenomenon called binocular rivalry. Previous studies have shown that exposure to signals from other senses can enhance the access of stimulation-congruent images to conscious perception. However, despite our ability to infer perceptual consequences from bodily movements, evidence that action can have an analogous influence on visual awareness is scarce and mainly limited to hand movements. Here, we investigated whether one's direction of locomotion affects perceptual access to optic flow patterns during binocular rivalry. Participants walked forwards and backwards on a treadmill while viewing highly-realistic visualisations of self-motion in a virtual environment. We hypothesised that visualisations congruent with walking direction would predominate in visual awareness over incongruent ones, and that this effect would increase with the precision of one's active proprioception. These predictions were not confirmed: optic flow consistent with forward locomotion was prioritised in visual awareness independently of walking direction and proprioceptive abilities. Our findings suggest the limited role of kinaesthetic-proprioceptive information in disambiguating visually perceived direction of self-motion and indicate that vision might be tuned to the (expanding) optic flow patterns prevalent in everyday life

    Peculiar Glitch of PSR J1119-6127 and Extension of the Vortex Creep Model

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    Glitches are sudden changes in rotation frequency and spin-down rate, observed from pulsars of all ages. Standard glitches are characterized by a positive step in angular velocity (ΔΩ\Delta\Omega > > 00) and a negative step in the spin-down rate (ΔΩ˙\Delta \dot \Omega < < 00) of the pulsar. There are no glitch-associated changes in the electromagnetic signature of rotation-powered pulsars in all cases so far. For the first time, in the last glitch of PSR J1119-6127, there is clear evidence for changing emission properties coincident with the glitch. This glitch is also unusual in its signature. Further, the absolute value of the spin-down rate actually decreases in the long term. This is in contrast to usual glitch behaviour. In this paper we extend the vortex creep model in order to take into account these peculiarities. We propose that a starquake with crustal plate movement towards the rotational poles of the star induces inward vortex motion which causes the unusual glitch signature. The component of the magnetic field perpendicular to the rotation axis will decrease, giving rise to a permanent change in the pulsar external torque.Comment: accepted by MNRAS, 10 pages, 2 figure

    Recreation Concept of The Chocolate Farmer Education Complex in North Kalimantan

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    The chocolate farmers in North Kalimantan, many do not know how and good chocolate treatment techniques, in order to get quality cocoa with high selling value. So that the resolution of the problem is by increasing the interest of the community, especially cocoa farmers, by providing attractive and comfortable containers, so that cocoa farmers can maximize the natural resources found on Sebatik island, North Kalimantan. To achieve this, the method used is to provide educational buildings, cocoa gardens, and processing facilities in one area. The process of obtaining a recreation concept in the chocolate farmers education complex includes several stages, ranging from identification, case studies, design programs and the basic concept of design. After going through these stages, a recreation concept is obtained in the form of a linear and centralized pattern of land structuring, which is a guide for visitors to access various facilities in the educational complex. It is expected that with the concept of this chocolate farmers education concept, it becomes a place of education and tourism that provides visitors with new comfort and knowledge

    Privacy Preserving Internet Browsers: Forensic Analysis of Browzar

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    With the advance of technology, Criminal Justice agencies are being confronted with an increased need to investigate crimes perpetuated partially or entirely over the Internet. These types of crime are known as cybercrimes. In order to conceal illegal online activity, criminals often use private browsing features or browsers designed to provide total browsing privacy. The use of private browsing is a common challenge faced in for example child exploitation investigations, which usually originate on the Internet. Although private browsing features are not designed specifically for criminal activity, they have become a valuable tool for criminals looking to conceal their online activity. As such, Technological Crime units often focus their forensic analysis on thoroughly examining the web history on a computer. Private browsing features and browsers often require a more in-depth, post mortem analysis. This often requires the use of multiple tools, as well as different forensic approaches to uncover incriminating evidence. This evidence may be required in a court of law, where analysts are often challenged both on their findings and on the tools and approaches used to recover evidence. However, there are very few research on evaluating of private browsing in terms of privacy preserving as well as forensic acquisition and analysis of privacy preserving internet browsers. Therefore in this chapter, we firstly review the private mode of popular internet browsers. Next, we describe the forensic acquisition and analysis of Browzar, a privacy preserving internet browser and compare it with other popular internet browser

    Genetic affinities of Helicobacter pylori isolates from ethnic Arabs in Kuwait

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    Helicobacter pylori is one of the most genetically diverse of bacterial species, and since the 5'-end of cagA gene and the middle allele of vacA gene of H. pylori from different populations exhibit considerable polymorphisms, these sequence diversities were used to gain insights into the genetic affinities of this gastric pathogen from different populations. Because the genetic affinity of Arab strains from the Arabian Gulf is not known, we carried out genetic analysis based on sequence diversities of the cagA and the vacA genes of H. pylori from 9 ethnic Arabs in Kuwait. The analysis showed that the Kuwaiti isolates are closely related to the Indo-European group of strains, although some strains have a tendency to form a separate cluster close to the Indo- European group, but clearly distinct from East Asian strains. However, these results need to be confirmed by analyses of neutral markers (house-keeping genes in a multi-locus sequence typing [MLST]) platform. The profiling of virulence-associated genes may have resulted from ecologically distinct populations due to human migration and geographical separation over long periods of time

    Waring–Goldbach Problem with Piatetski-Shapiro Primes

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    In this paper, we exhibit an asymptotic formula for the number of representations of a large integer as a sum of a fixed power of Piatetski-Shapiro primes, thereby establishing a variant of Waring-Goldbach problem with primes from a sparse sequence

    OpenVirtualObjects: An open set of standardized and validated 3D household objects for virtual reality-based research, assessment, and therapy

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    Virtual reality (VR) technology provides clinicians, therapists, and researchers with new opportunities to observe, assess, and train behavior in realistic yet well-controlled environments. However, VR also comes with a number of challenges. For example, compared to more abstract experiments and tests on 2D computer screens, VR-based tasks are more complex to create, which can make it more expensive and time-consuming. One way to overcome these challenges is to create, standardize, and validate VR content and to make it openly available for researchers and clinicians. Here we introduce the OpenVirtualObjects (OVO), a set of 124 realistic 3D household objects that people encounter and use in their everyday lives. The objects were rated by 34 younger and 25 older adults for recognizability, familiarity, details (i.e., visual complexity), contact, and usage (i.e., frequency of usage in daily life). All participants also named and categorized the objects. We provide the data and the experiment- and analysis code online. With OVO, we hope to facilitate VR-based research and clinical applications. Easy and free availability of standardized and validated 3D objects can support systematic VR-based studies and the development of VR-based diagnostics and therapeutic tools

    OpenVirtualObjects (OVO): An open set of standardized and validated 3D household objects for virtual reality-based research, assessment, and therapy

    Get PDF
    Virtual reality (VR) technology provides clinicians, therapists, and researchers with new opportunities to observe, assess, and train behaviour in realistic yet well-controlled environments. However, VR also comes with a number of challenges. For example, compared to more abstract experiments and tests on 2D computer screens, VR-based tasks are more complex to create, which can make it more expensive and time-consuming. One way to overcome these challenges is to create, standardize, and validate VR content and to make it openly available for researchers and clinicians. Here we introduce the OpenVirtualObjects (OVO), a set of 124 realistic 3D household objects that people encounter and use in their everyday lives. The objects were rated by 34 younger and 25 older adults for recognizability, familiarity, details (i.e., visual complexity), contact, and usage (i.e., frequency of usage in daily life). All participants also named and categorized the objects. We provide the data and the experiment- and analysis code online. With OVO, we hope to facilitate VR-based research and clinical applications. Easy and free availability of standardized and validated 3D objects can support systematic VR-based studies and the development of VR-based diagnostics and therapeutic tools

    Nonlinear interglitch dynamics, the braking index of the Vela pulsar and the time to the next glitch

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    The interglitch timing of the Vela pulsar is characterized by a constant second derivative of the rotation rate. This takes over after the post-glitch exponential relaxation and is completed at about the time of the next glitch. The vortex creep model explains the second derivatives in terms of nonlinear response to the glitch. We present interglitch timing fits to the present sample covering 16 large glitches, taking into account the possibility that in some glitches part of the step in the spin-down rate may involve a ‘persistent shift’, as observed in the Crab pulsar. Modifying the expression for the time between glitches with this hypothesis leads to better agreement with the observed interglitch time intervals. We extrapolate the interglitch model fits to obtain spin-down rates just prior to each glitch and use these to calculate the braking index n = 2.81 ± 0.12. The next glitch should occur around 2017 December 22, ±197 d if no persistent shift is involved, but could occur as early as 2016 July 27, ±152 d if the 2013 glitch gave rise to a typical Vela persistent shift. Note added: Literally while we were submitting the first version of this paper on 2016 December 12, we saw ATel # 9847 announcing a Vela pulsar glitch which has arrived 138 d after our prediction with a persistent shift, within the 1σ uncertainty of 152 d

    The Cytotoxicity and Insecticidal Activity of Extracts from Delphinium formosum Boiss. & Huet

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    Delphinium species are well-known toxic plants with diterpenoid alkaloid contents. There has been no previous investigation on the cytotoxicity of Delphinium formosum. The extracts of the different parts of D. formosum, an endemic species in Turkey, were investigated for their cytotoxic activity against the human liver carcinoma cell line (HepG2) and primary human umbilical vein endothelial cells (HUVEC). The cytotoxic effects of twelve extracts and subfractions were determined against HepG2 cells using the MTT assay. The only active extract was applied to the HUVEC as a model for healthy cells. Only one of the alkaloidcontaining extracts from the aerial parts was toxic (IC50=244,9 µg/mL against HepG2 and 144,4 µg/mL against HUVEC), while the root extracts were inactive. The results were improbable although it is predicted secondary metabolites, such as diterpene alkaloids (methyllycaconitine, browniine, lycoctonine, avardharidine, antranoyllycoctonine, delsemine A/B and lycoctonine). Based on previous studies in the literature, the cytotoxic plants were also expected to exhibit insecticidal activity. Therefore, the cytotoxic extract of D. formosum was examined for its adulticidal and larvicidal activity against the yellow fever, dengue fever and the Zika virus vector Aedes aegypti L
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