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An IEEE 802.15.4 Based Adaptive Communication Protocol in Wireless Sensor Network: Application to Monitoring the Elderly at Home

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Wireless Sensor Network 2014年第9期6卷 192-204页

作者： Juan Lu adrien van den bossche Eric Campo Univ de Toulouse Toulouse France CNRS LAAS Toulouse France CNRS IRIT Toulouse France

Monitoring behaviour of the elderly and the disabled living alone has become a major public health problem in our modern societies. Among the various scientific aspects involved in the home monitoring field, we are interested in the study and the proposal of a solution allowing distributed sensor nodes to communicate with each other in an optimal way adapted to the specific application constraints. More precisely, we want to build a wireless network that consists of several short range sensor nodes exchanging data between them according to a communication protocol at MAC (Medium Access Control) level. This protocol must be able to optimize energy consumption, transmission time and loss of information. To achieve this objective, we have analyzed the advantages and the limitations of WSN (Wireless Sensor Network) technologies and communication protocols currently used in relation to the requirements of our application. Then we proposed a deterministic, adaptive and energy saving medium access method based on the IEEE 802.15.4 physical layer and a mesh topology. It ensures the message delivery time with strongly limited collision risk due to the spatial reuse of medium in the two-hop neighbourhood. This proposal was characterized by modelling and simulation using OPNET network simulator. Finally we implemented the proposed mechanisms on hardware devices and deployed a sensors network in real situation to verify the accuracy of the model and evaluate the proposal according to different test configurations.

关键词： Wireless Sensor Network Medium Access Control Quality of Service Energy Saving Mesh Topology IEEE 802.15.4 Indoor Monitoring Application

Comparison of Indoor Localization Systems Based on Wireless Communications

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How non-rapid eye movement sleep and Alzheimer pathology are linked

Wireless Engineering and Technology 2011年第4期

作者： Rejane Dalce Thierry Val adrien van den bossche

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World Journal of Psychiatry 2021年第11期11卷 1027-1038页

作者： Annelies Falter Maarten J A van den bossche Department of Geriatric Psychiatry University Psychiatric Center KU LeuvenLeuven 3000Belgium Center for Neuropsychiatry Research Group PsychiatryDepartment of NeurosciencesLeuven Brain InstituteKU LeuvenLeuven 3000Belgium

Alzheimer's disease(AD)is a multifactorial neurodegenerative disorder characterized by the presence of senile plaques and neurofibrillary *** attempts to identify characteristic factors that are associated with the presence of the AD pathology on the one hand and that increase the risk of developing AD on the *** in non-rapid eye movement(NREM)sleep may meet both requirements for various ***,NREM-sleep is important for optimal memory *** addition,studies report that the presence of AD pathology is associated with NREM-sleep ***,more and more results appear to suggest that sleep problems are not only a symptom of AD but can also increase the risk of *** of these studies suggest that it is primarily a lack of NREM-sleep that is responsible for this increased ***,the majority investigated sleep only through subjective reporting,as a result of which NREMsleep could not be analyzed *** aim of this literature study is therefore to present the results of the studies that relate the AD pathology and NREM-sleep(registered by electroencephalography).Furthermore,we try to evaluate whether NREM-sleep analysis could be used to support the diagnosis of AD and whether NREM-sleep deficiency could be a causal factor in the development of AD.

关键词： Alzheimer’s disease Mild cognitive impairment Sleep Non-rapid eye movement sleep Amyloid beta-peptides Tau proteins Electroencephalography

Counting the SNAREs needed for membrane fusion

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Journal of Molecular Cell Biology 2011年第4期3卷 204-205页

作者： Geert van den Bogaart Reinhard Jahn Department of Neurobiology Max-Planck Institute for Biophysical ChemistryAm Fassberg 1137077 GottingenGermany

SNARE proteins mediate most membrane fusion reactions in eukaryotic cells,and are thereby vital for many functions,including synaptic transmission,cell growth,and ***,until recently it was still unclear how many of these proteins are required to catalyze membrane fusion in *** a recent Science paper,Mohrmann et al.(2010)elegantly show that in chromaffin cells,three SNARE complexes are required for the synchronous release of granules,whereas only a single SNARE complex is sufficient for overall release.

关键词： release thereby complexes

Management strategies to improve the nitrogen use efficiency in grasslands and the protein quality in grass silages:Lessons from a practical study on dairy farms in Flanders

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Grassland Research 2024年第1期3卷 18-32页

作者： Tine van den bossche Johan LDe Boever Geert Haesaert Mathias Cougnon Sandra Debevere Leen vandaele Karen Goossens ILVO MelleBelgium Department of Plant and Crops Ghent UniversityGhentBelgium Inagro Rumbeke-BeitemBelgium

Background:Long-term overgrazing has led to severe degradation of grasslands,posing a signiﬁcant threat to the sustainable use of grassland ***:Based on the investigation of changes in functional traits and photosynthetic physiology of Stipa breviﬂora under no grazing,moderate grazing,and heavy grazing treatments,the changes in expression patterns of genes and proteins associated with different grazing intensities were assessed through integrative transcriptomic and proteomic ***:Differentially expressed genes and proteins were identiﬁed under different grazing *** were mainly related to RNA processing,carbon metabolism,and secondary metabolite ***ﬁndings suggest that long-term grazing leads to molecular phenotypic plasticity,affecting various biological processes and metabolic pathways in ***ﬂ*** analysis revealed low correlation between the transcriptome and the proteome,indicating a large-scale regulation of gene expression at the posttranscriptional and translational levels during the response of ***ﬂora to *** expression proﬁles of key genes and proteins involved in photosynthesis and phenylpropanoid metabolism pathways suggested their synergistic response to grazing in ***ﬂ***:Our study provides insight into the adaptation mechanisms of ***ﬂora to grazing and provides a scientiﬁc basis for the development of more efﬁcient grassland protection and utilization practices.

关键词： clover grassland grasssilage management nitrogenuseefficiency proteinquality

Functionalized monodisperse microbubble production:microfluidic method for fast,controlled,and automated removal of excess coating material

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Microsystems & Nanoengineering 2024年第4期10卷 391-401页

作者： M.R.P.van den Broek M.Versluis A.van den Berg T.Segers BIOS/Lab on a Chip Group Max Planck Center Twente for Complex Fluid DynamicsUniversity of TwenteEnschedeThe Netherlands Physics of Fluids Group University of TwenteEnschedeThe Netherlands

Functionalized monodisperse microbubbles have the potential to boost the sensitivity and efficacy of molecular ultrasound imaging and targeted drug delivery using bubbles and *** bubbles can be produced in a microfluidic flow focusing ***,their functionalization and sequential use require removal of the excess lipids from the bubble suspension to minimize the use of expensive ligands and to avoid competitive binding and blocking of the receptor *** date,excess lipid removal is performed by centrifugation,which is labor intensive and challenging to *** importantly,as we show,the increased hydrostatic pressure during centrifugation can reduce bubble ***,we introduce a novel automated microfluidic’washing’***,bubbles are injected in a microfluidic chamber 1mm in height where they are left to float against the top ***,lipid-free medium is pumped through the chamber to remove excess lipids while the bubbles remain located at the top ***,the washed bubbles are resuspended and removed from the device into a collection *** demonstrate that the present method can(i)reduce the excess lipid concentration by 4 orders of magnitude,(ii)be fully automated,and(iii)be performed in minutes while the size distribution,functionality,and acoustic response of the bubbles remain ***,the presented method is a gateway to the fully automated production of functionalized monodisperse microbubbles.

关键词： bubble fluid method

Impact of black cherry on pedunculate oak vitality in mixed forests:Balancing benefits and concerns

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Forest Ecosystems 2023年第6期10卷 690-699页

作者： Ellen Desie Bart Muys Jan den Ouden Bart Nyssen Rita Sousa-Silva Leon van den Berg Arnold van den Burg Gert-Jan van Duinen Koenraad van Meerbeek Maaike Weijters Karen vancampenhout Division Forest Nature and LandscapeKU Leuven Campus GeelKleinhoefstraat 4B-2240 GeelBelgium Division Forest Nature and LandscapeKU LeuvenCelestijnenlaan 200EBox 2411B-3001 LeuvenBelgium KU Leuven Plant Institute B-3001 LeuvenBelgium Forest Ecology and Management Group Wageningen UniversityP.O.Box 47Wageningenthe Netherlands Bosgroep Zuid-Nederland Huisvenseweg 145591 VD Heezethe Netherlands Young Academy for Sustainability Research University of Freiburg79104 Freiburg im BreisgauGermany Aquatic Ecology&Environmental Biology Radboud University NijmegenHeyendaalseweg 1356525 AJ Nijmegenthe Netherlands Biosphere/Zoological Museum Netherlands Onderlangs 176731 BK Otterlothe Netherlands Stichting Bargerveen Toernooiveld 16525 ED Nijmegenthe Netherlands B-WARE Research Centre/Radboud University Nijmegen Toernooiveld 16525 ED Nijmegenthe Netherlands

The vitality of European forests continues to decline due to new pests and diseases,climate-change related disturbances and high loads of atmospheric nitrogen *** soil health is a major factor underpinning the low vitality of West-European *** tree species with soil ameliorative traits is proposed as an avenue to counteract soil acidification and improve overall forest *** we evaluate the impact of black cherry(Prunus serotina Ehrh.),a known rich litter species,on the vitality of neighboring pedunculate oak(Quercus robur L.)in ten mixed forests on sand in Germany,Belgium and the *** found that black cherry admixture increases foliar N and P to a surplus whereas it causes deficiencies in foliar Mg,thereby resulting in an overall negative effect on oak foliar nutrient ***,defoliation of oak leaves by herbivory decreases with the proximity of black *** structural equation modelling(SEM),we tested the hypothesized‘improved soil health’*** analyses showed that black cherry admixture leads to lower accumulation in the humus layer,resulting in higher soil base saturation which has a positive effect on foliar Ca yet a negative effect on total ***,the SEM illustrated that herbivory of oak leaves decreases when black cherry is admixed,both via dilution and improved soil *** effects of black cherry on oak vitality via“improved soil health”in our SEM are however small in comparison to direct ***,our study showed that the combined positive and negative impacts of black cherry on oak vitality are limited,which tempers the potential benefits of using the rich litter species to counteract oak decline via improved soil health–yet,the concern of black cherry as an invasive alien species negatively affecting the vitality of mature pedunculate oak trees may also be exaggerated.

关键词： Rich litter species Black cherry Nutrient cycling Insect herbivory Dilution effect Humus type Pedunculate oak Plant-soil interaction

Deciphering fluid inclusions in high-grade rocks

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Geoscience Frontiers 2014年第5期5卷 683-695页

作者： Alfons van den Kerkhof Andreas Kronz Klaus Simon Geowissenschaftliches Zentrum der Universitat Gottingen Goldschmidtstr.1-3 D 37073 GottingenGermany

The study of fluid inclusions in high-grade rocks is especially challenging as the host minerals have been normally subjected to deformation, recrystallization and fluid-rock interaction so that primary in- clusions, formed at the peak of metamorphism are rare. The larger part of the fluid inclusions found in metamorphic minerals is typically modified during uplift. These late processes may strongly disguise the characteristics of the ＂original＂ peak metamorphic fluid. A detailed microstructural analysis of the host minerals, notably quartz, is therefore indispensable for a proper interpretation of fluid inclusions. Cathodoluminescence （CL） techniques combined with trace element analysis of quartz （EPMA, LA- [CPMS） have shown to be very helpful in deciphering the rock-fluid evolution. Whereas high-grade metamorphic quartz may have relatively high contents of trace elements like Ti and A1, low- temperature re-equilibrated quartz typically shows reduced trace element concentrations. The result- ing microstructures in CL can be basically distinguished in diffusion patterns （along microfractures and grain boundaries）, and secondary quartz formed by dissolution-reprecipitation. Most of these textures are formed during retrograde fluid-controlled processes between ca. 220 and 500 ℃, i.e. the range of semi-brittle deformation （greenschist-facies） and can be correlated with the fluid inclusions. In this way modified and re-trapped fluids can be identified, even when there are no optical features observed under the microscope.

关键词： Fluid inclusionsGranuliteCharnockiteCathodoluminescenceLA-ICPMSQuartz

The significance of NO_(2) dimerization in plasma-based NO_(x) synthesis for nitrogen fixation

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Journal of Energy Chemistry 2024年第12期99卷 522-528页

作者： Thijs van Raak Huub van den Bogaard Fausto Gallucci Sirui Li Sustainable Process Engineering Department of Chemical Engineering and ChemistryEindhoven University of TechnologyDe Rondom 70Eindhoven 5612 APthe Netherlands Eindhoven Institute for Renewable Energy Systems(EIRES) Eindhoven University of TechnologyPO Box 513Eindhoven 5600 MBthe Netherlands

Plasma-based NO_(x) synthesis has been considered as a sustainable alternative to the conventional HaberBosch *** the advancements in research achieved in recent years,limited attention has been paid to the reversible dimerization reaction of NO_(2) to N_(2)O_(4).This reaction can significantly alter the parameters considered with the process’output,such as the concentration or volume fraction of products and the energy *** work aims to investigate the significance of dimerization through theoretical analysis and *** were conducted with a 2D-gliding arc reactor to evaluate the influence of dimerization in the case of plasma reactor *** was observed that the dimerization reaction reached equilibrium in microseconds,resulting in a maximum hypothetical NO_(2) equilibrium conversion of 48.8%.For plasma experiments,the dimerization could cause a maximum error of 14.1%in product detection,which needs to be carefully considered along with the influence of temperature variations on the measurement.

关键词： Nitrogen fixation N_(2)O_(4) Dimerization NO_(x)synthesis Non-thermal plasma Gliding arc reactor