165 research outputs found

    A Novel Authentication and Validation Mechanism for Analyzing Syslogs Forensically

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    This research proposes a novel technique for authenticating and validating syslogs for forensic analysis. This technique uses a modification of the Needham Schroeder protocol, which uses nonces (numbers used only once) and public keys. Syslogs, which were developed from an event-logging perspective and not from an evidence-sustaining one, are system treasure maps that chart out and pinpoint attacks and attack attempts. Over the past few years, research on securing syslogs has yielded enhanced syslog protocols that focus on tamper prevention and detection. However, many of these protocols, though efficient from a security perspective, are inadequate when forensics comes into play. From a legal perspective, any kind of evidence found at a crime scene needs to be validated. In addition, any digital forensic evidence when presented in court needs to be admissible, authentic, believable, and reliable. Currently, a patchy log on the server side and client side cannot be considered as formal authentication of a wrongdoer. This work presents a method that ties together, authenticates, and validates all the entities involved in the crime scene--the user using the application, the system that is being used, and the application being used on the system by the user. This means that instead of merely transmitting the header and the message, which is the standard syslog protocol format, the syslog entry along with the user fingerprint, application fingerprint, and system fingerprint are transmitted to the logging server. The assignment of digital fingerprints and the addition of a challenge response mechanism to the underlying syslogging mechanism aim to validate generated syslogs forensically

    The Behavioral Regulation in Exercise Questionnaire (BREQ-4): Psychometric evidence of introjected approach regulation in Portuguese health club exercisers

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    The assessment of motivation has been a key aspect to the understanding of exercise participation, and research grounded in self-determination theory has presented valid and reliable instruments for that purpose. Given the need to continually refine this latent construct, the present study aimed to translate, adapt, and psychometrically validate a subscale targeting the approach facet of introjection, and to test the pattern of associations between motives for practice, basic psychological needs satisfaction/frustration, and behavioral regulations encompassing the validated introjection subscale, in a sample of health club exercisers. For that purpose, two studies were developed with a total of 1216 health club exercisers. In Study I (n = 806), Confirmatory Factor Analysis and Exploratory Structural Equation Modeling analysis to test the motivational continuum encompassing the introjected approach subscale were performed. In Study II (n = 410) associations and structural models between intrinsic and extrinsic goal contents, basic psychological needs satisfaction and frustration, and behavioral regulations with the new subscale were tested. The correlated seven-factor model with 21 items in Study I displayed good psychometric properties (CFA: χ2 = 481.977 (168), p < .001, CFI = 0.936, TLI = 0.915, SRMR = 0.037, RMSEA = 0.048; ESEM: χ2 = 178.672 (84), p < .001, CFI = 0.980, TLI = 0.949, SRMR = 0.014, RMSEA = 0.037). The introjected approach regulation added to the preexisting factorial structure did not affect the validity and reliability of the instrument. The results from Study II supported a theoretically expected pattern of associations, in which the introjected regulation of approach is positioned between introjected avoidance and identified regulation along the motivational continuum. Additionally, path estimates depicted criterion validity for the new subscale. All in all, this work presents preliminary evidence for an introjected approach regulation subscale that can be used in health club practices for a better understanding of the motivational quality of exercise practice.info:eu-repo/semantics/publishedVersio

    Observation of Scaling Violations in Scaled Momentum Distributions at HERA

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    Charged particle production has been measured in deep inelastic scattering (DIS) events over a large range of xx and Q2Q^2 using the ZEUS detector. The evolution of the scaled momentum, xpx_p, with Q2,Q^2, in the range 10 to 1280 GeV2GeV^2, has been investigated in the current fragmentation region of the Breit frame. The results show clear evidence, in a single experiment, for scaling violations in scaled momenta as a function of Q2Q^2.Comment: 21 pages including 4 figures, to be published in Physics Letters B. Two references adde

    D* Production in Deep Inelastic Scattering at HERA

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    This paper presents measurements of D^{*\pm} production in deep inelastic scattering from collisions between 27.5 GeV positrons and 820 GeV protons. The data have been taken with the ZEUS detector at HERA. The decay channel D+(D0Kπ+)π+D^{*+}\to (D^0 \to K^- \pi^+) \pi^+ (+ c.c.) has been used in the study. The e+pe^+p cross section for inclusive D^{*\pm} production with 5<Q2<100GeV25<Q^2<100 GeV^2 and y<0.7y<0.7 is 5.3 \pms 1.0 \pms 0.8 nb in the kinematic region {1.3<pT(D±)<9.01.3<p_T(D^{*\pm})<9.0 GeV and η(D±)<1.5| \eta(D^{*\pm}) |<1.5}. Differential cross sections as functions of p_T(D^{*\pm}), η(D±),W\eta(D^{*\pm}), W and Q2Q^2 are compared with next-to-leading order QCD calculations based on the photon-gluon fusion production mechanism. After an extrapolation of the cross section to the full kinematic region in p_T(D^{*\pm}) and η\eta(D^{*\pm}), the charm contribution F2ccˉ(x,Q2)F_2^{c\bar{c}}(x,Q^2) to the proton structure function is determined for Bjorken xx between 2 \cdot 104^{-4} and 5 \cdot 103^{-3}.Comment: 17 pages including 4 figure

    A two-component pre-seeded dermal-epidermal scaffold

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    We have developed a bilayered dermal-epidermal scaffold for application in the treatment of full-thickness skin defects. The dermal component gels in situ and adapts to the lesion shape, delivering human dermal fibroblasts in a matrix of fibrin and cross-linked hyaluronic acid modified with a cell adhesion-promoting peptide. Fibroblasts were able to form a tridimensional matrix due to material features such as tailored mechanical properties, presence of protease-degradable elements and cell-binding ligands. The epidermal component is a robust membrane containing cross-linked hyaluronic acid and poly-l-lysine, on which keratinocytes were able to attach and to form a monolayer. Amine-aldehyde bonding at the interface between the two components allows the formation of a tightly bound composite scaffold. Both parts of the scaffold were designed to provide cell-type-specific cues to allow for cell proliferation and form a construct that mimics the skin environment.D.S.K. acknowledges funding from the Biotechnology Research Endowment from the Department of Anesthesiology at Boston Children's Hospital. I.P.M. acknowledges the Portuguese Foundation for Science and Technology for the grant BD/39396/2007 and the MIT-Portugal Program. D.G. acknowledges the Swiss National Science Foundation for a post-doctoral fellowship (PBGEP3-129111). B.P.T. acknowledges an NIR Ruth L. Kirschstein National Research Service Award (F32GM096546)

    The Lamb shift in muonic hydrogen and the proton radius

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    By means of pulsed laser spectroscopy applied to muonic hydrogen (μ− p) we have measured the 2S F = 1 1/2 − 2PF = 2 3/2 transition frequency to be 49881.88(76) GHz. By comparing this measurement with its theoretical prediction based on bound-state QED we have determined a proton radius value of rp = 0.84184 (67) fm. This new value is an order of magnitude preciser than previous results but disagrees by 5 standard deviations from the CODATA and the electronproton scattering values. An overview of the present effort attempting to solve the observed discrepancy is given. Using the measured isotope shift of the 1S-2S transition in regular hydrogen and deuterium also the rms charge radius of the deuteron rd = 2.12809 (31) fm has been determined. Moreover we present here the motivations for the measurements of the μ 4He + and μ 3He + 2S-2P splittings. The alpha and triton charge radii are extracted from these measurements with relative accuracies of few 10 − 4. Measurements could help to solve the observed discrepancy, lead to the best test of hydrogen-like energy levels and provide crucial tests for few-nucleon ab-initio theories and potentials

    Factors related to human-vector contact that modify the likelihood of malaria transmission during a contained Plasmodium falciparum outbreak in Praia, Cabo Verde

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    Background: Determining the reproductive rate and how it varies over time and space (RT) provides important insight to understand transmission of a given disease and inform optimal strategies for controlling or eliminating it. Estimating RT for malaria is difficult partly due to the widespread use of interventions and immunity to disease masking incident infections. A malaria outbreak in Praia, Cabo Verde in 2017 provided a unique opportunity to estimate RT directly, providing a proxy for the intensity of vector-human contact and measure the impact of vector control measures. Methods: Out of 442 confirmed malaria cases reported in 2017 in Praia, 321 (73%) were geolocated and informed this analysis. RT was calculated using the joint likelihood of transmission between two cases, based on the time (serial interval) and physical distance (spatial interval) between them. Log-linear regression was used to estimate factors associated with changes in RT, including the impact of vector control interventions. A geostatistical model was developed to highlight areas receptive to transmission where vector control activities could be focused in future to prevent or interrupt transmission. Results: The RT from individual cases ranged between 0 and 11 with a median serial- and spatial-interval of 34 days [interquartile range (IQR): 17–52] and 1,347 m (IQR: 832–1,985 m), respectively. The number of households receiving indoor residual spraying (IRS) 4 weeks prior was associated with a reduction in RT by 0.84 [95% confidence interval (CI) 0.80–0.89; p-value &lt;0.001] in the peak-and post-epidemic compared to the pre-epidemic period. Conclusions: Identifying the effect of reduced human-vector contact through IRS is essential to determining optimal intervention strategies that modify the likelihood of malaria transmission and can inform optimal intervention strategies to accelerate time to elimination. The distance within which two cases are plausibly linked is important for the potential scale of any reactive interventions as well as classifying infections as imported or introduced and confirming malaria elimination

    Modelo cognitivo-motivacional para la promoción de la persistencia en Educación Superior: relación entre la organización docente, la competencia del alumnado y el «grit»

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    The teaching process and the success of learning are closely linked to cognitive and motivational factors. The purpose of this study was to test a multilevel model in higher education students on the relationship between the teaching organization and the dimensions of grit and perceived competence. Participated 3033 students, who answered utility dimension inventories and organization, competition and grit. The results show that at the individual level, the organization by the teaching staff focused on the utility and organization is positively related to the student's scream, this relationship being mediated by the perceived competence. The organizational improvement of the teacher generates student achievements through the positive impact on their competence.«El proceso de enseñanza y el éxito del aprendizaje están estrechamente vinculados a factores cognitivos y motivacionales. Este estudio tuvo como propósito poner a prueba un modelo multinivel en estudiantes de Educación Superior sobre la relación de la organización docente y las dimensiones del grit, mediada por la competencia percibida. Participaron 3.033 estudiantes de cinco países, a los que se les midió la utilidad y organización del docente, la competencia y el grit. Los resultados muestran que, a nivel individual, la organización por parte del profesorado centrada en la utilidad se relacionó positivamente con el grit del estudiante cuando estaba mediada por la competencia percibida. Se sugiere que el profesor mejore su tarea organizativa docente, pues genera mayores logros en el estudiante a través del impacto positivo sobre su competencia
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