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Machine-learning-based optical spectrum feature analysis for DoS attack detection in IP over optical networks
Get PDFData availability. Data underlying the results presented in this paper are not publicly available at this time but may be obtained from the authors upon reasonable request.In this paper, we introduce a novel approach for detecting Denial of Service (DoS) attacks in software-defined IP over optical networks, leveraging machine learning to analyze optical spectrum features. This method employs machine learning to automatically process optical spectrum data, which is indicative of network security status, thereby identifying potential DoS attacks. To validate its effectiveness, we conducted both numerical simulations and experimental trials to collect relevant optical spectrum datasets. We then assessed the performance of three machine learning algorithms XGBoost, LightGBM, and the BP neural network in detecting DoS attacks. Our findings show that all three algorithms demonstrate a detection accuracy exceeding 97%, with the BP neural network achieving the highest accuracy rates of 99.55% and 99.74% in simulations and experiments, respectively. This research not only offers a new avenue for DoS attack detection but also enhances early detection capabilities in the underlying optical network through optical spectrum data analysis.National Key Research and Development Program of China (2023YFB2906200); National Natural Science Foundation of China (62075024, 62201105, 62205043, 62025105, 62221005, 62222103, 62331017); Chongqing Municipal Education Commission (CXQT21019, KJQN202100643)
Is lifetime traumatic brain injury a risk factor for mild cognitive impairment in veterans compared to non-veterans?
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Owing to the nature of the research, for ethical reasons supporting data are not available.Supplemental data for this article can be accessed online at: https://doi.org/10.1080/20008066.2023.2291965 .Background: Traumatic brain injury (TBI) is prevalent in veterans and may occur at any stages of their life (before, during, or after military service). This is of particular concern, as previous evidence in the general population has identified TBI as a strong risk factor for mild cognitive impairment (MCI), a known precursor of dementia.
Objectives: This study aimed to investigate whether exposure to at least one TBI across the lifetime was a risk factor for MCI in ageing UK veterans compared to non-veterans.
Method: This cross-sectional study comprised of data from PROTECT, a cohort study comprising UK veterans and non-veterans aged β₯β50 years at baseline. Veteran and TBI status were self-reported using the Military Service History Questionnaire (MSHQ) and the Brain Injury Screening Questionnaire (BISQ), respectively. MCI was the outcome of interest, and was defined as subjective cognitive impairment and objective cognitive impairment.
Results: The sample population comprised of veterans (nβ=β701) and non-veterans (nβ=β12,389). TBI was a significant risk factor for MCI in the overall sample (ORβ=β1.21, 95% CI 1.11β1.31) compared to individuals without TBI. The prevalence of TBI was significantly higher in veterans compared to non-veterans (69.9% vs 59.5%, pβ<β.001). There was no significant difference in the risk of MCI between veterans with TBI and non-veterans with TBI (ORβ=β1.19, 95% CI 0.98β1.45).
Conclusion: TBI remains an important risk factor for MCI, irrespective of veteran status. The clinical implications indicate the need for early intervention for MCI prevention after TBI.Resumen: Antecedentes: El traumatismo encΓ©falocraneano (TEC) es frecuente en veteranos, el cual puede ocurrir en cualquier etapa de sus vidas (antes, durante o despuΓ©s del servicio militar). Esto es motivo de preocupaciΓ³n, ya que evidencia previa en la poblaciΓ³n general ha identificado al TEC como un fuerte factor de riesgo de Deterioro Cognitivo Leve (DCL), un precursor conocido de demencia.
Objetivo: Este estudio tuvo como objetivo investigar si la exposiciΓ³n a al menos un Traumatismo encΓ©falocraneano a lo largo de la vida era un factor de riesgo de Deterioro Cognitivo Leve en veteranos del Reino Unido en comparaciΓ³n con no veteranos.
MΓ©todo: Este estudio de corte transversal incluyΓ³ datos de PROTECT, un estudio de cohorte que incluye a veteranos y no veteranos del Reino Unido de β₯50 aΓ±os al inicio del estudio. El estatus de veterano y de Traumatismo encΓ©falocraneano (TEC) se auto-reportaron utilizando el Cuestionario de Historia de Servicio Militar (MSHQ, por sus siglas en inglΓ©s) y el Cuestionario de DetecciΓ³n de Traumatismo encΓ©falocraneano (BISQ, por sus siglas en inglΓ©s), respectivamente. El Deterioro Cognitivo Leve (DCL) fue el resultado de interΓ©s, definido como deterioro cognitivo subjetivo y deterioro cognitivo objetivo.
Resultados: La muestra poblacional incluyΓ³ a veteranos (nβ=β701) y no veteranos (nβ=β12.389). El Traumatismo encΓ©falocraneano (TEC) fue un factor de riesgo significativo de Deterioro Cognitivo Leve (DCL) en la muestra total (ORβ=β1.21, IC del 95% 1.11β1.31) en comparaciΓ³n con individuos sin TEC. La prevalencia de TEC fue significativamente mayor en veteranos en comparaciΓ³n con no veteranos (69.9% vs 59.5%, pβ<β.001). No hubo diferencia significativa en el riesgo de DCL entre veteranos con TEC y no veteranos con TEC (ORβ=β1.19, IC del 95% 0.98β1.45).
ConclusiΓ³n: El Traumatismo encΓ©falocraneano (TEC) continΓΊa siendo un factor de riesgo significativo de Deterioro Cognitivo Leve (DCL), independiente del estatus de veterano. Las implicaciones clΓnicas sugieren la necesidad de intervenciones tempranas para la prevenciΓ³n de DCL despuΓ©s de un TEC.PhD studentship by the Alzheimerβs Society (award no. 475 [AS-PhD-18b-002]). The PROTECT study was externally funded/supported by the National Institute of Health and Care Research, Exeter Biomedical Research Centre. The views expressed are those of the authors and not necessarily those of the NIHR or the Department of Health and Social Care. The Family History of Neurological Disease Questionnaire was funded in part by the Alzheimerβs Research UK South West Network
How does team learning from failure facilitate new product performance? The double-edged moderating effect of collective efficacy
Get PDFJEL Classification: D83 Β· D91 Β· L25 Β· O31 Β· O32Learning from failure can foster innovation, but how a new product development (NPD) teamβs learning from failure affects new product performance requires more insights. In particular, the question remains on how collective efficacy, which discerns team membersβ belief to achieve desired goals, affects team learning from failure towards improving new product performance. Using social cognitive theory complemented by sensemaking and attribution theories, we examine the effects of NPD teamsβ (experiential and vicarious) learning from failure on new product performance and the moderating effects of collective efficacy on these relationships. With survey data collected from 398 responses within 152 NPD teams in Chinese high-tech small and medium-sized enterprises, we find that both experiential and vicarious learning from failure enhance new product performance in terms of speed to market and product innovativeness. Further, as collective efficacy increases, the positive effect of experiential learning from failure on speed to market is strengthened. However, the positive effect of vicarious learning from failure on product innovativeness is weakened. Our results suggest that NPD teams can benefit from experiential and vicarious learning from failure to improve new product performance but must pay attention to the double-edged effect of collective efficacy
Coupled atomisticβcontinuum simulations of nucleate boiling
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The software used to generate the data is publicly available on github and linked to the submission.Boiling is a striking example of a multiscale process, where the dynamics of bubbles is governed by the interplay between the molecular interactions responsible for nucleation, and the macroscale hydrodynamic and thermal boundary layers. A complete description of this phenomenon requires coupling molecular- and continuum-scale fluid mechanics into a single modelling framework. This article presents a hybrid atomisticβcontinuum computational model for coupled simulations of nucleate boiling. A domain decomposition coupling method is utilised, where the near-wall region is solved by a Molecular Dynamics description, which handles nucleation and the moving contact lines, while the bulk flow region is solved by a continuum-scale description based on the NavierβStokes equations. The latter employs a Volume Of Fluid method to track the evolution of the liquidβvapour interface and the interphase mass transfer is computed via the HertzβKnudsenβSchrage relationship. Boiling of a Lennard-Jones fluid over a heated wall is simulated and the hybrid solution is validated against a fully molecular solution. The results obtained with the coupled framework in terms of time-dependent bubble volume, phase-change rates, bubble dynamics and evolution of the temperature field agree quantitatively with those achieved by a MD-only simulation. The coupled framework reproduces the bubble growth rate over time from nucleation until a bubble diameter of about 70 nm, demonstrating the accuracy and robustness of the coupling architecture. This also demonstrates that the fluid dynamics description based on the NavierβStokes equations is capable of correctly capturing the main heat and mass transfer mechanisms responsible for bubble growth at the nanoscale. The proposed modelling framework paves the way towards multiscale simulations of boiling, where the necessary molecular-level physics is retained in a computational fluid dynamics solver.This work was funded under the embedded CSE programme of the ARCHER2 UK National Supercomputing Service (https://www.archer2.ac.uk), project ARCHER2-eCSE06-1 βHybrid AtomisticβContinuum Simulations of Boiling Across Scalesβ
Barriers and enablers for cycling: A COM-B survey study of UK schoolchildren and their parents
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Cycling confers many health-related benefits but is rarely used as a mode of travel in the UK. There is comparatively limited research on enablers and barriers to cycling in children and their parents, even though understanding this dyad is key for developing effective active school travel interventions. We used the COM-B (capability, opportunity, and motivation to engage in an identified behaviour) model as a framework to design and interpret data from an online survey administered to schoolchildren and their parents, regarding barriers and enablers for cycling.
Methods:
Two hundred-and-forty-six UK schoolchildren aged 9β15 years (M = 12.2 yrs; SD = 1.1 yrs) and one of their parents completed an online survey in which they reported their cycling behaviour, physical and psychological capabilities regarding cycling on roads, social and physical opportunities for cycling, and their motivation to cycle on roads. A structural equation model was hypothesized and fitted to the data. Model modifications were made to improve the model fit.
Results:
A structural equation model of survey data revealed that parents' cycling frequency predicted the frequency of their children's cycling. Both children's and parents' cycling frequencies were determined by their affective judgements regarding cycling β i.e., their automatic motivation to cycle β and whether they had access to a roadworthy cycle. Parents' cycling frequency was also influenced by the proportion of their close friends who cycled.
Conclusions:
Interventions targeted at enhancing children's and parents' attitudes toward cycling, and increasing parents' cycling behaviour, may increase children's cycling frequency journeys such as the school commute.This work was funded by a widening access grant from The Department of Transport and The Bikeability Trust
Comparison for the effects of different components of temperature variability on mortality: A multi-country time-series study
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The authors do not have permission to share data.Supplementary data are available online at: https://www.sciencedirect.com/science/article/pii/S0160412024002988?via%3Dihub#s0095 .Background:
Temperature variability (TV) is associated with increased mortality risk. However, it is still unknown whether intra-day or inter-day TV has a higher effect.
Objectives:
We aimed to assess the association of intra-day TV and inter-day TV with all-cause, cardiovascular, and respiratory mortality.
Methods:
We collected data on total, cardiovascular, and respiratory mortality and meteorology from 758 locations in 47 countries or regions from 1972 to 2020. We defined inter-day TV as the standard deviation (SD) of daily mean temperatures across the lag interval, and intra-day TV as the average SD of minimum and maximum temperatures on each day. In the first stage, inter-day and intra-day TVs were modelled simultaneously in the quasi-Poisson time-series model for each location. In the second stage, a multi-level analysis was used to pool the location-specific estimates.
Results:
Overall, the mortality risk due to each interquartile range [IQR] increase was higher for intra-day TV than for inter-day TV. The risk increased by 0.59% (95% confidence interval [CI]: 0.53, 0.65) for all-cause mortality, 0.64% (95% CI: 0.56, 0.73) for cardiovascular mortality, and 0.65% (95% CI: 0.49, 0.80) for respiratory mortality per IQR increase in intra-day TV0β7 (0.9β―Β°C). An IQR increase in inter-day TV0β7 (1.6β―Β°C) was associated with 0.22% (95% CI: 0.18, 0.26) increase in all-cause mortality, 0.44% (95% CI: 0.37, 0.50) increase in cardiovascular mortality, and 0.31% (95% CI: 0.21, 0.41) increase in respiratory mortality. The proportion of all-cause deaths attributable to intra-day TV0β7 and inter-day TV0β7 was 1.45% and 0.35%, respectively. The mortality risks varied by lag interval, climate area, season, and climate type.
Conclusions:
Our results indicated that intra-day TV may explain the main part of the mortality risk related to TV and suggested that comprehensive evaluations should be proposed in more countries to help protect human health.This study was supported by the Australian Research Council (DP210102076) and the Australian National Health and Medical Research Council (GNT2000581). BW by China Scholarship Council (number 202006010043); WY by China Scholarship Council (number 202006010044); SL by an Emerging Leader Fellowship of the Australian National Health and Medical Research Council (number GNT2009866); JK and AU by the Czech Science Foundation (project number 20β28560S); NS by the National Institute of Environmental Health Sciences-funded HERCULES Center (P30ES019776); S-CP and YLG by the Ministry of Science and Technology (Taiwan; MOST 109β2621-M-002β021); YH by the Environment Research and Technology Development Fund (JPMEERF15S11412) of the Environmental Restoration and Conservation Agency; MdSZSC and PHNS by the SΓ£o Paulo Research Foundation (FAPESP); ST by the Science and Technology Commission of Shanghai Municipality (grant number 18411951600); HO and EI by the Estonian Ministry of Education and Research (IUT34β17); JM by a fellowship of Fundação para a CiΓͺncia e a Tecnlogia (SFRH/BPD/115112/2016); AG by the Medical Research Council UK (grant IDs: MR/V034162/1 and MR/R013349/1), the Natural Environment Research Council UK (grant ID: NE/R009384/1), and the EU's Horizon 2020 project, Exhaustion (grant ID: 820655); AS, SR, and FdD by the EU's Horizon 2020 project, Exhaustion (grant ID 820655); VH by the Spanish Ministry of Economy, Industry and Competitiveness (grant ID PCIN-2017β046); AT by MCIN/AEI/10.13039/501100011033 (grant CEX2018-000794-S); YG by Career Development Fellowship (number GNT1163693) and Leader Fellowship (number GNT2008813) of the Australian National Health and Medical Research Council; Statistics South Africa kindly provided the mortality data, but had no other role in the study. This Article is published in memory of Simona Fratianni who helped to contribute the data for Romania
Seasonality of mortality under climate change: a multicountry projection study
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All data used in our study were obtained from the MCC Collaborative Research Network under a data-sharing agreement and cannot be made publicly available. Researchers can refer to collaborators of the Network, who are listed as coauthors of this Article (primary contact: Antonio Gasparrini, [email protected]), for information on accessing the data for each country. The R code is available on request, and a reproducible example is publicly available on the personal GitHub website of the first author (https://github.com/LinaMadaniyazi).For more on the MCC see https://mccstudy.lshtm.ac.uk/Supplementary Material is available online at: https://www.sciencedirect.com/science/article/pii/S2542519623002693#sec1 .Background:
Climate change can directly impact temperature-related excess deaths and might subsequently change the seasonal variation in mortality. In this study, we aimed to provide a systematic and comprehensive assessment of potential future changes in the seasonal variation, or seasonality, of mortality across different climate zones.
Methods:
In this modelling study, we collected daily time series of mean temperature and mortality (all causes or non-external causes only) via the Multi-Country Multi-City Collaborative (MCC) Research Network. These data were collected during overlapping periods, spanning from Jan 1, 1969 to Dec 31, 2020. We projected daily mortality from Jan 1, 2000 to Dec 31, 2099, under four climate change scenarios corresponding to increasing emissions (Shared Socioeconomic Pathways [SSP] scenarios SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5). We compared the seasonality in projected mortality between decades by its shape, timings (the day-of-year) of minimum (trough) and maximum (peak) mortality, and sizes (peak-to-trough ratio and attributable fraction). Attributable fraction was used to measure the burden of seasonality of mortality. The results were summarised by climate zones.
Findings:
The MCC dataset included 126β809β537 deaths from 707 locations within 43 countries or areas. After excluding the only two polar locations (both high-altitude locations in Peru) from climatic zone assessments, we analysed 126β766β164 deaths in 705 locations aggregated in four climate zones (tropical, arid, temperate, and continental). From the 2000s to the 2090s, our projections showed an increase in mortality during the warm seasons and a decrease in mortality during the cold seasons, albeit with mortality remaining high during the cold seasons, under all four SSP scenarios in the arid, temperate, and continental zones. The magnitude of this changing pattern was more pronounced under the high-emission scenarios (SSP3-7.0 and SSP5-8.5), substantially altering the shape of seasonality of mortality and, under the highest emission scenario (SSP5-8.5), shifting the mortality peak from cold seasons to warm seasons in arid, temperate, and continental zones, and increasing the size of seasonality in all zones except the arid zone by the end of the century. In the 2090s compared with the 2000s, the change in peak-to-trough ratio (relative scale) ranged from 0Β·96 to 1Β·11, and the change in attributable fraction ranged from 0Β·002% to 0Β·06% under the SSP5-8.5 (highest emission) scenario.
Interpretation:
A warming climate can substantially change the seasonality of mortality in the future. Our projections suggest that health-care systems should consider preparing for a potentially increased demand during warm seasons and sustained high demand during cold seasons, particularly in regions characterised by arid, temperate, and continental climates.This study was primarily supported by the Environment Research and Technology Development Fund (grant number JPMEERF20231007) of the Environmental Restoration and Conservation Agency, provided by the Ministry of the Environment of Japan. MH was supported by the Japan Science and Technology Agency as part of the Strategic International Collaborative Research Program (grant number JPMJSC20E4). AG was supported by the UK Medical Research Council (grant number MR/V034162/1) and the EU's Horizon 2020 research project Exhaustion (grant number 820655). AU and JK were supported by the Czech Science Foundation (project 22β24920S). JJKJ was supported by the Academy of Finland (grant number 310372; Global Health Risks Related to Atmospheric Composition and Weather Consortium). FS was supported by the Italian Ministry of University and Research, Department of Excellence project 2023β2027, Rethinking Data ScienceβDepartment of Statistics, Computer Science and ApplicationsβUniversity of Florence
Regional blood flow in the human leg with local heating and low-intensity exercise in young and old humans
No full textThis thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University LondonPassive heating has been used for millennia as a therapeutic method to improve
health and wellbeing. Contemporary research indicates that heating may have the
potential to instigate positive vascular adaptation due to large increases in blood flow
and thus, shear stress. However, the precise vascular locus in which hyperthermia
modulates perfusion remains elusive. Moreover, the literature exploring the acute
haemodynamic responses to heating and exercise in elderly populations, who might
benefit the most from heat and exercise interventions, is riddled with inconsistencies.
Consequently, the present thesis aimed to (1) investigate the local temperature and
haemodynamic responses to various levels of leg and leg-segmental heating, and (2)
examine the leg haemodynamic responses among single-leg hyperthermia, kneeextensor
exercise, and their combination in healthy, active aged adults. The results
from Chapter 4 and 4 demonstrate a strong relationship between local tissue
temperature and perfusion, and between the volume of heated tissue and perfusion.
The magnitude of hyperaemia during segmental-leg heating corresponded to the
regional hyperaemia of that particular leg-segment during whole-leg hyperthermia.
During these various levels of local heating, blood flow solely increased in the heated
areas with no changes in temperature and perfusion in the unheated contralateral and
adject limb segments, alongside a maintained core temperature and central
haemodynamics. Furthermore, Chapter 6 uncovered that single-leg heating, kneeextensor
exercise, and their combination induced substantial increases in
hyperaemiaβfrom smallest to largest, respectivelyβwith hyperthermia having an
additive effect on functional hyperaemia. A similar magnitude of functional hyperaemia
was observed between the elderly and young cohorts, despite the presence of ageassociated
structural vascular changes. Collectively, these novel data indicate that
peripheral tissue perfusion during local hyperthermia is primarily regulated by local
thermosensitive mechanisms and that local heating may be a suitable intervention for
the improvement or maintenance of vascular health in elderly individuals
A practical guide to cross-cultural and multi-sited data collection in the biological and behavioural sciences
Get PDFData accessibility:
This article has no additional data. The project materials and data used in specific analyses can be found on the Open Science Framework at: https://osf.io/mztep/.Electronic supplementary material is available online: Spake L et al. 2024 A practical guide to cross-cultural and multi-sited data collection in the biological and behavioural sciences. Figshare. (https://doi:org/10.6084/m9.figshare.c.7165766).Declaration of AI use:
We have not used AI-assisted technologies in creating this article.Researchers in the biological and behavioural sciences are increasingly conducting collaborative, multi-sited projects to address how phenomena vary across ecologies. These types of projects, however, pose additional workflow challenges beyond those typically encountered in single-sited projects. Through specific attention to cross-cultural research projects, we highlight four key aspects of multi-sited projects that must be considered during the design phase to ensure success: (1) project and team management; (2) protocol and instrument development; (3) data management and documentation; and (4) equitable and collaborative practices. Our recommendations are supported by examples from our experiences collaborating on the Evolutionary Demography of Religion project, a mixed-methods project collecting data across five countries in collaboration with research partners in each host country. To existing discourse, we contribute new recommendations around team and project management, introduce practical recommendations for exploring the validity of instruments through qualitative techniques during piloting, highlight the importance of good documentation at all steps of the project, and demonstrate how data management workflows can be strengthened through open science practices. While this project was rooted in cross-cultural human behavioural ecology and evolutionary anthropology, lessons learned from this project are applicable to multi-sited research across the biological and behavioural sciences.John Templeton Foundation (grant nos. 61425, 62773); Templeton Religion Trust (grant no. TRT-2022-30378)
Stability analysis for the phytoplankton-zooplankton model with depletion of dissolved oxygen and strong Allee effects
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Data sharing is not applicable to this article as no data-sets were generated or analyzed during this study.MSC 2020: 34D05, 34D20, 34D23, 34D45, 92D40, 92D25.The photosynthetic activity of phytoplankton in the seas is responsible for an estimated 50-80% of the world's oxygen generation. Both phytoplankton and zooplankton require some of this synthesized oxygen for cellular respiration. This study aims to better understand how the oxygen-phytoplankton dynamics are altered due to the Allee effect in phytoplankton development, particularly when considering the time-dependent oxygen generation rate. The dynamic analysis of the model is dedicated to finding the possible equilibrium points. The analysis reveals that three equilibrium points can be obtained. The stability study demonstrates that one of the equilibrium points is always stable. The remaining equilibrium points are stable under specific conditions. We also identify bifurcations originating from these equilibrium points, including transcritical, pitchfork, and Hopf bifurcation. We derive conditions for stable limit cycles (supercritical Hopf bifurcation) and, in some cases, establish the non-existence of solutions. Numerical simulations are performed to validate our theoretical findings. Furthermore, it is noted that the Allee threshold for the phytoplankton population ( significantly influences the overall dynamics of the system. When , the population of plankton is at risk of extinction. On the other hand, when , the population of zooplankton is at risk of extinction. When , the solution reaches a stable condition of coexistence. Conversely, when , the solution exhibits periodic attractor behavior
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