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Machine Learning in Chemical Engineering:Strengths,Weaknesses,Opportunities,and Threats

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Engineering 2021年第9期7卷 1201-1211页

作者： maarten r.dobbelaere Pieter P.Plehiers ruben Van de Vijver Christian V.Stevens Kevin M.Van Geem Laboratory for Chemical Technology Department of MaterialsTextiles and Chemical EngineeringGhent UniversityGhent 9052Belgium SynBioC research Group Department of Green Chemistry and TechnologyFaculty of Bioscience EngineeringGhent UniversityGhent 9000Belgium

Chemical engineers rely on models for design,research,and daily decision-making,often with potentially large financial and safety implications.Previous efforts a few decades ago to combine artificial intelligence and chemical engineering for modeling were unable to fulfill the expectations.In the last five years,the increasing availability of data and computational resources has led to a resurgence in machine learning-based research.Many recent efforts have facilitated the roll-out of machine learning techniques in the research field by developing large databases,benchmarks,and representations for chemical applications and new machine learning frameworks.Machine learning has significant advantages over traditional modeling techniques,including flexibility,accuracy,and execution speed.These strengths also come with weaknesses,such as the lack of interpretability of these black-box models.The greatest opportunities involve using machine learning in time-limited applications such as real-time optimization and planning that require high accuracy and that can build on models with a self-learning ability to recognize patterns,learn from data,and become more intelligent over time.The greatest threat in artificial intelligence research today is inappropriate use because most chemical engineers have had limited training in computer science and data analysis.Nevertheless,machine learning will definitely become a trustworthy element in the modeling toolbox of chemical engineers.

关键词： Artificial intelligence Machine learning reaction engineering Process engineering

Safe reinforcement learning for multi-energy management systems with known constraint functions

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能源与人工智能(英文)

能源与人工智能(英文) 2023年第2期12卷 86-102页

作者： Glenn Ceusters Luis ramirez Camargo rüdiger Franke Ann Nowé maarten Messagie ABB Hoge Wei 271930 ZaventemBelgium Vrije Universiteit Brussel(VUB) ETEC-MOBIPleinlaan 21050 BrusselsBelgium Vrije Universiteit Brussel(VUB) AI-labPleinlaan 21050 BrusselsBelgium Copernicus Institute of Sustainable Development-Utrecht University Princetonlaan 8a3584CB UtrechtNetherlands

reinforcement learning(rL)is a promising optimal control technique for multi-energy management systems.It does not require a model a priori-reducing the upfront and ongoing project-specific engineering effort and is capable of learning better representations of the underlying system dynamics.However,vanilla rL does not provide constraint satisfaction guarantees—resulting in various potentially unsafe interactions within its environment.In this paper,we present two novel online model-free safe rL methods,namely SafeFallback and GiveSafe,where the safety constraint formulation is decoupled from the rL formulation.These provide hard-constraint satisfaction guarantees both during training and deployment of the(near)optimal policy.This is without the need of solving a mathematical program,resulting in less computational power requirements and more flexible constraint function formulations.In a simulated multi-energy systems case study we have shown that both methods start with a significantly higher utility compared to a vanilla rL benchmark and Optlayer benchmark(94,6%and 82,8%compared to 35,5%and 77,8%)and that the proposed SafeFallback method even can outperform the vanilla rL benchmark(102,9%to 100%).We conclude that both methods are viably safety constraint handling techniques applicable beyond rL,as demonstrated with random policies while still providing hard-constraint guarantees.

关键词： reinforcement learning Constraints Multi-energy systems Energy management system

S-scheme CoTiO_(3)/Cd_(9.51)Zn_(0.49)S_(10)heterostructures for visible-light driven photocatalytic CO_(2) reduction

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Journal of Materials Science & Technology 2022年第29期124卷 164-170页

作者： Bo Su Haowei Huang Zhengxin Ding maarten B.J.roeffaers Sibo Wang Jinlin Long State Key Lab of Photocatalysis on Energy and Environment College of Chemistry Fuzhou UniversityFuzhou 350108China cMACS Department of Microbial and Molecular SystemsKU LeuvenCelestijnenlaan 200FLeuven 3001Belgium

CdZnS solid solutions with strong light absorption are promising materials for solar-driven COreduction;however,their relatively weak redox ability and intrinsic photo-corrosion limit their further development as a photocatalyst.The addition of a second photocatalyst with a suitable band structure to construct a S-scheme photocatalytic system can solve both problems simultaneously.Here,we report a S-scheme photocatalyst based on the heterostructure of CoTiO_(3)/CdZnS(abbreviated as CoTiO_(3)/Cd_(9.51)Zn_(0.49)S_(10))that enables the efficient photocatalytic reduction of CO.Detailed physicochemical characterization resolves the S-scheme charge transfer mechanism in this composite photocatalyst.With the well-designed structure of particles and desirable band offsets,this hybrid system offers visible light absorption in a broad spectral region,large surface area,strong redox ability,and fast carrier separation and transportation.Under visible-light illumination,the CoTiO_(3)/Cd Zn S hybrid system displays a CO formation rate of about 11 mmol hgcombined with a long-term operational stability.Besides,a high apparent quantum efficiency(AQE)of 7.27%is realized for the CO_(2)-to-CO reduction reaction by the optimized Co TiO/Cd Zn S hybrid under 420 nm monochromatic light irradiation.

关键词： Photocatalysis CO_(2)reduction S-scheme Metal sulfides Heterostructure

Intra-arterial thrombolytics during endovascular thrombectomy for acute ischaemic stroke in the Mr CLEAN registry

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Stroke & Vascular Neurology 2023年第1期8卷 17-25页

作者： Sabine L Collette reinoud P H Bokkers Aryan Mazuri Geert J LycklamaàNijeholt robert J van Oostenbrugge Natalie E LeCouffe Faysal Benali Charles B L M Majoie Jan Cees de Groot Gert Jan r Luijckx maarten Uyttenboogaart 无 Department of radiology Medical Imaging CentreUniversity Medical Centre GroningenUniversity of GroningenGroningenthe Netherlands Department of radiology Haaglanden Medical CentreThe Haguethe Netherlands Department of Neurology Cardiovascular Research Institute Maastricht(CARIM)Maastricht University Medical CentreMaastrichtthe Netherlands Department of Neurology Amsterdam UMCUniversity of AmsterdamAmsterdam NeuroscienceAmsterdamthe Netherlands Department of radiology Maastricht University Medical CentreMaastrichtthe Netherlands Department of radiology and Nuclear Medicine Amsterdam UMCUniversity of AmsterdamAmsterdam NeuroscienceAmsterdamthe Netherlands Department of Neurology University Medical Centre GroningenUniversity of GroningenGroningenthe Netherlands On behalf of the Mr CLEAN registry investigators

Introduction The efficacy and safety of local intra-arterial(IA)thrombolytics during endovascular thrombectomy(EVT)for large-vessel occlusions is uncertain.We analysed how often IA thrombolytics were administered in the Multicenter randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands(Mr CLEAN)registry,whether it was associated with improved functional outcome and assessed technical and safety outcomes compared with EVT without IA thrombolytics.Methods In this observational study,we included patients undergoing EVT for an acute ischaemic stroke in the anterior circulation from the Mr CLEAN registry(March 2014-November 2017).The primary endpoint was favourable functional outcome,defined as an modified rankin Scale score≤2 at 90 days.Secondary endpoints were reperfusion status,early neurological recovery and symptomatic intracranial haemorrhage(sICH).Subgroup analyses for IA thrombolytics as primary versus adjuvant revascularisation attempt were performed.results Of the 2263 included patients,95(4.2%)received IA thrombolytics during EVT.The IA thrombolytics administered were urokinase(median dose,250000 IU(IQr,193750-250000))or alteplase(median dose,20 mg(IQr,12-20)).No association was found between IA thrombolytics and favourable functional outcome(adjusted Or(aOr),1.16;95%CI 0.71 to 1.90).Successful reperfusion was less often observed in those patients treated with IA thrombolytics(aOr,0.57;95%CI 0.36 to 0.90).The odds of sICH(aOr,0.82;95%CI 0.32 to 2.10)and early neurological recovery were comparable between patients treated with and without IA thrombolytics.For primary and adjuvant revascularisation attempts,IA thrombolytics were more often administered for proximal than for distal occlusions.Functional outcomes were comparable for patients receiving IA thrombolytics as a primary versus adjuvant revascularisation attempt.Conclusion Local IA thrombolytics were rarely used in the Mr CLEAN registry.In the relatively small study sample,no statistical difference was observe

关键词： arterial throm acute

Effect of carcass contamination on necrophagous invertebrate performance

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Ecological Processes 2021年第1期10卷 795-803页

作者： Ellard r.Hunting maarten Schrama Daniel E.rozen Christina Joenssen Nadja r.Brun Institute of Environmental Sciences Leiden UniversityLeidenThe Netherlands. School of Biological Sciences University of BristolBristolUK. Naturalis Biodiversity Centre LeidenThe Netherlands. Institute of Biology Leiden UniversityLeidenThe Netherlands. Current Address:Department of Biological Sciences University of BergenBergenNorway

Background:The breakdown of dead organic matter is driven by a diverse array of organisms and is an important process increasingly impacted by a range of contaminants.While many studies have documented how contaminants affect food webs that are fueled by decaying plant litters,much less is known about how contaminants affect organisms that rely on dead animal material.Here,we begin to explore the effects of food contamination—using silver nanoparticles(AgNPs)as a model contaminant—on the carrion beetle Nicrophorus vespilloides that buries carcasses of small vertebrates in soils as food source and larval nursing grounds.results:Our data show that a single ingestion of a non-lethal dose of 1μg mL^(−1) AgNPs by adult female beetles does not affect overall gut microbial activity but results in shifts in the gut microbial community composition towards pathogens including Alcaligenes,Morganella,and Pseudomonas.While no effects were observed in offspring clutch size,some reductions were visible in clutch weight,number of larvae,and number of eclosing pupae in exposed N.vespilloides in comparison with controls.repeated ingestion of AgNPs over several weeks led to a decrease in survival of adult beetles,suggesting that more environmentally realistic exposure scenarios can directly affect the success of carcass-feeding animals.Conclusions:Sub-lethal carcass contamination with a model pollutant can affect the gut microbial composition in female beetles and reduce offspring fitness.This encourages consideration of currently overlooked propagation routes of contaminants through necrophagous food webs and inherent consequences for ecological and evolutionary processes.

关键词： Gut microbiome Maternal transfer Offspring fitness DECOTAB Nanoparticles Bactericidal compounds Carrion beetle Nicrophorus vespilloides

Management of extracranial carotid artery stenosis during endovascular treatment for acute ischaemic stroke:results from the Mr CLEAN registry

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Stroke & Vascular Neurology 2023年第3期8卷 229-237,I0074-I0085页

作者： Sabine L Collette Michael P rodgers Marianne A A van Walderveen Kars C J Compagne Paul J Nederkoorn Jeannette Hofmeijer Jasper M Martens Gert J de Borst Gert Jan r Luijckx Charles B L M Majoie Aad van der Lugt reinoud P H Bokkers maarten Uyttenboogaart University Medical Centre Groningen University of GroningenGroningenThe Netherlands Leiden University Medical Centre LeidenThe Netherlands Erasmus MC University Medical CentreRotterdamThe Netherlands Amsterdam University Medical Centres University of AmsterdamAmsterdamThe Netherlands rijnstate Hospital ArnhemThe Netherlands University Medical Centre Utrecht University of UtrechtUtrechtThe Netherlands

Background The optimal management of ipsilateral extracranial internal carotid artery(ICA)stenosis during endovascular treatment(EVT)is unclear.We compared the outcomes of two different strategies:EVT with vs without carotid artery stenting(CAS).Methods In this observational study,we included patients who had an acute ischaemic stroke undergoing EVT and a concomitant ipsilateral extracranial ICA stenosis of≥50%or occlusion of presumed atherosclerotic origin,from the Dutch Multicenter randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands(Mr CLEAN)registry(2014-2017).The primary endpoint was a good functional outcome at 90 days,defined as a modified rankin Scale score≤2.Secondary endpoints were successful intracranial reperfusion,new clot in a different vascular territory,symptomatic intracranial haemorrhage,recurrent ischaemic stroke and any serious adverse event.results Of the 433 included patients,169(39%)underwent EVT with CAS.In 123/168(73%)patients,CAS was performed before intracranial thrombectomy.In 42/224(19%)patients who underwent EVT without CAS,a deferred carotid endarterectomy or CAS was performed.EVT with and without CAS were associated with similar proportions of good functional outcome(47%vs 42%,respectively;adjusted Or(aOr),0.90;95%CI,0.50 to 1.62).There were no major differences between the groups in any of the secondary endpoints,except for the increased odds of a new clot in a different vascular territory in the EVT with CAS group(aOr,2.96;95%CI,1.07 to 8.21).Conclusions Functional outcomes were comparable after EVT with and without CAS.CAS during EVT might be a feasible option to treat the extracranial ICA stenosis but randomised studies are warranted to prove non-inferiority or superiority.

关键词： stenosis carotid treatment

regulatory control of the Na-Cl co-transporter NCC and its therapeutic potential for hypertension

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Acta Pharmaceutica Sinica B 2021年第5期11卷 1117-1128页

作者： Nur Farah Meor Azlan maarten P.Koeners Jinwei Zhang Institute of Biomedical and Clinical Sciences Medical SchoolCollege of Medicine and HealthUniversity of ExeterHatherly LaboratoriesExeter EX44PSUK

Hypertension is the largest risk factor for cardiovascular disease,the leading cause of mortality worldwide.As blood pressure regulation is influenced by multiple physiological systems,hypertension cannot be attributed to a single identifiable etiology.Three decades of research into Mendelian forms of hypertension implicated alterations in the renal tubular sodium handling,particularly the distal convoluted tubule(DCT)-native,thiazide-sensitive Na-Cl cotransporter(NCC).Altered functions of the NCC have shown to have profound effects on blood pressure regulation as illustrated by the over activation and inactivation of the NCC in Gordon’s and Gitelman syndromes respectively.Substantial progress has uncovered multiple factors that affect the expression and activity of the NCC.In particular,NCC activity is controlled by phosphorylation/dephosphorylation,and NCC expression is facilitated by glycosylation and negatively regulated by ubiquitination.Studies have even found parvalbumin to be an unexpected regulator of the NCC.In recent years,there have been considerable advances in our understanding of NCC control mechanisms,particularly via the pathway containing the with-no-lysine[K](WNK)and its downstream target kinases,SPS/Ste20-related proline-alanine-rich kinase(SPAK)and oxidative stress responsive 1(OSr1),which has led to the discovery of novel inhibitory molecules.This review summarizes the currently reported regulatory mechanisms of the NCC and discusses their potential as therapeutic targets for treating hypertension.

关键词： NaCl-cotransporter NCC Cardiovascular disease CUL3/KLHL3-WNK-SPAK/OSr1 Blood pressure regulation Kinase inhibitors Membrane trafficking Therapeutic targets Hypertension

Toward more reliable stability measurements in stance: recommendations for number of measurements, foot position and feedback——a cross-sectional study among servicemen

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Military Medical research 2020年第2期7卷 199-208页

作者： Saskia Maria Theresia van der Heijden maarten reinders Prins Peter van der Wurff Physical Therapy Sciences Program in Clinical Health SciencesUniversity Medical Center Utrecht3584CX UtrechtThe Netherlands research and Development Military Rehabilitation Center AardenburgKorte Molenweg 33941PW DoomThe Netherlands Department of Human Movement Sciences Faculty of Behavioural and Movement SciencesVrije Universiteit Amsterdam and Amsterdam Movement Sciences1081BT AmsterdamThe Netherlands Institute for Human Movement Studies HU University of Applied Sciences Utrecht3584CS UtrechtThe Netherlands

Background:In the military,insufficient postural stability is a risk factor for developing lower extremity injuries.Postural stability training programs are effective in preventing these injuries.However,an objective method for the measurement of postural stability in servicemen is lacking.The primary objective of this study was to assess the influence of the number of repetitions,different foot positions and real-time visual feedback on postural stability,as well as their effects on the intrasession reliability of postural stability measurements in servicemen.The secondary objective was to assess the concurrent validity of the measurements.Methods:Twenty healthy servicemen between 20 and 50 years of age and in active duty were eligible for this quantitative,cross-sectional study.The measurements took place on a force plate,measuring the mean velocity of the center of pressure.The participants were asked to stand as still as possible in three different foot positions(wide stance,small stance,and on one leg),five times each for 45 s each time,and the measurements were performed with and without real-time visual feedback.results:We observed a significant main effect of foot position(Pr repetition number(P=0.915).Postural stability decreased in the more challenging foot positions.The ICC estimates varied from 0.809(one repetition in wide stance)to 0.985(five repetitions on one leg).The common variance(r2)between different foot positions without feedback varied between 0.008(wide stance)and 0.412.Conclusions:To yield reliable data,wide-stance measurements should be conducted three times,and small-stance measurements and measurements on one leg should be conducted two times.The scores of a measurement in a particular foot position cannot predict the scores of measurements in other foot positions.

关键词： Postural stability Center of Pressure Servicemen Intrasession reliability Concurrent validity

Small-Scale Mineralogical Heterogeneity from Variations in Phase Assemblages in the Transition Zone and D" Layer Predicted by Convection Modelling

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Journal of Earth Science 2011年第2期22卷 160-168页

作者： Arie P van den Berg David A Yuen Michael H G Jacobs maarten V de Hoop Earth Sciences Department Utrecht University Department of Geology and Geophysics and Minnesota Supercomputing Institute University of MinnesotaMinneapolisMN 55415USA Institut für Metallurgie TU ClausthalClausthal-ZellerfeldGermany Department of Mathematics and Center of Applied and Computational Mathematics Purdue UniversityWest LafayetteINUSA

Small-scale heterogeneity in the deep mantle is concentrated in the upper-mantle transition zone （TZ）, in the depth range 410-660 km and also at the bottom 250 km D＂ region. This encourages a more detailed investigation of the potential for seismic reflectivity imaging by modelling heterogeneous structures in mantle convection models including phase transitions of the TZ and D＂ regions. We applied finite elements with variable spacing near the boundary layers in 2-D cylindrical geometry that allow for sufficient spatial resolution. We investigated several models including an extended Boussinesq （EBA） model, focused on the D＂ region, and a compressible （ALA） model for the TZ region. The results for the D＂ region show typical lens-shaped structures of post-perovskite （PPV） embedded in the perovskite （PV） background mantle, where the thickness of the lenses, at 200-400 km, strongly depends on the Clapeyron slope of the PV-PPV transition. A second phase transition （double crossing） occurs in case the core temperature is higher than the intercept temperature Ti. Our phase-dependent rheology results in contrasting effective viscosity between PV and PPV. Our model results reveal a distinctly clear mechanical weakening of the PPV lenses with about an order of magnitude lower viscosity. The shear wave-speed distributions computed from our convection results are strongly correlated with the heterogeneous distribution of the mineral phase. Gradients in the seismic wave-speed that are the target of seismological reflectivity imaging are clearly revealed. The wave-speed results show a clear resolution of the top and bottom interfaces of the PPV lenses. Our ALA model for the TZ is based on a thermodynamical model for the magnesium end- member of an olivine-pyroxene mantle. The model predicts a much more complex distribution of mineral phases, compared to our D＂ results, in agreement with the greater number of mineral phases involved in the olivine-pyroxene phase diagram for the P, T conditions of the transition zone. Near cold

关键词： mantle convection phase transition post-perovskite mineralogical heterogeneity.