AIM:To study whether selected bacterial 16S ribosomal RNA(rRNA)gene phylotypes are capable of disting- uishing irritable bowel syndrome(IBS). METHODS:The faecal microbiota of twenty volunteers with IBS,subdivided into...AIM:To study whether selected bacterial 16S ribosomal RNA(rRNA)gene phylotypes are capable of disting- uishing irritable bowel syndrome(IBS). METHODS:The faecal microbiota of twenty volunteers with IBS,subdivided into eight diarrhoea-predominant (IBS-D),eight constipation-predominant(IBS-C)and four mixed symptom-subtype(IBS-M)IBS patients,and fifteen control subjects,were analysed at three time-points with a set of fourteen quantitative real-timepolymerase chain reaction assays.All assays targeted 16S rRNA gene phylotypes putatively associated with IBS,based on 16S rRNA gene library sequence analysis. The target phylotypes were affiliated with Actinobac-teria,Bacteroidetes and Firmicutes.Eight of the target phylotypes had less than 95%similarity to cultured bacterial species according to their 16S rRNA gene sequence.The data analyses were made with repeated-measures ANCOVA-type modelling of the data and principle component analysis(PCA)with linear mixed-effects models applied to the principal component scores. RESULTS:Bacterial phylotypes Clostridium cocleatum 88%,Clostridium thermosuccinogenes 85%,Coprobacillus catenaformis 91%,Ruminococcus bromii-like, Ruminococcus torques 91%,and R.torques 93%were detected from all samples analysed.A multivariate analysis of the relative quantities of all 14 bacterial 16S rRNA gene phylotypes suggested that the intestinal microbiota of the IBS-D patients differed from other sample groups.The PCA on the first principal component(PC1),explaining 30.36%of the observed variation in the IBS-D patient group,was significantly altered from all other sample groups(IBS-D vs control, P=0.01;IBS-D vs IBS-M,P=0.00;IBS-D vs IBS-C, P=0.05).Significant differences were also observed in the levels of distinct phylotypes using relative values in proportion to the total amount of bacteria.A phy- lotype with 85%similarity to C.thermosuccinogenes was quantified in significantly different quantities among the IBS-D and control subjects(-4.08±0.90 vs -3.33±1.16,P=0.04)and IBS-D and IBS-M subjects 展开更多
In this article we propose to facilitate local peer-to-peer communication by a Device-to-Device (D2D) radio that operates as an underlay network to an IMT-Advanced cellular network. It is expected that local services ...In this article we propose to facilitate local peer-to-peer communication by a Device-to-Device (D2D) radio that operates as an underlay network to an IMT-Advanced cellular network. It is expected that local services may utilize mobile peer-to-peer communication instead of central server based communication for rich mul-timedia services. The main challenge of the underlay radio in a multi-cell environment is to limit the inter-ference to the cellular network while achieving a reasonable link budget for the D2D radio. We propose a novel power control mechanism for D2D connections that share cellular uplink resources. The mechanism limits the maximum D2D transmit power utilizing cellular power control information of the devices in D2D communication. Thereby it enables underlaying D2D communication even in interference-limited networks with full load and without degrading the performance of the cellular network. Secondly, we study a single cell scenario consisting of a device communicating with the base station and two devices that communicate with each other. The results demonstrate that the D2D radio, sharing the same resources as the cellular net-work, can provide higher capacity (sum rate) compared to pure cellular communication where all the data is transmitted through the base station.展开更多
Sustainable and resilient pavement infrastructure is critical for current economic and environmental challenges.In the past 10 years,the pavement infrastructure strongly supports the rapid development of the global so...Sustainable and resilient pavement infrastructure is critical for current economic and environmental challenges.In the past 10 years,the pavement infrastructure strongly supports the rapid development of the global social economy.New theories,new methods,new technologies and new materials related to pavement engineering are emerging.Deterioration of pavement infrastructure is a typical multi-physics problem.Because of actual coupled behaviors of traffic and environmental conditions,predictions of pavement service life become more and more complicated and require a deep knowledge of pavement material analysis.In order to summarize the current and determine the future research of pavement engineering,Journal of Traffic and Transportation Engineering(English Edition)has launched a review paper on the topic of"New innovations in pavement materials and engineering:A review on pavement engineering research 2021".Based on the joint-effort of 43 scholars from 24 well-known universities in highway engineering,this review paper systematically analyzes the research status and future development direction of 5 major fields of pavement engineering in the world.The content includes asphalt binder performance and modeling,mixture performance and modeling of pavement materials,multi-scale mechanics,green and sustainable pavement,and intelligent pavement.Overall,this review paper is able to provide references and insights for researchers and engineers in the field of pavement engineering.展开更多
Light emitting diode(LED)lighting is becoming more and more popular,as incandescent lamps are being phased out globally.LEDs have several advantages over incandescent lamps,including energy efficiency,robustness,long ...Light emitting diode(LED)lighting is becoming more and more popular,as incandescent lamps are being phased out globally.LEDs have several advantages over incandescent lamps,including energy efficiency,robustness,long lifetime,and good temporal stability.The three latter features make LEDs attractive candidates as new photometric standards.Because the spectra of white LEDs are limited to the visible wavelength range,a novel method for the realization of photometric units based on the predictable quantum efficient detector(PQED)can be utilized.The method eliminates the need of photometric filters that are traditionally used in photometry,and instead relies on carrying out the photometric weighting numerically based on the measured relative spectrum of the source.The PQED-based realization simplifies the traceability chain of photometric measurements significantly as compared with the traditional filter-based method.The measured illuminance values of a white LED deviate by only 0.03%when determined by the new and the traditional methods.The new PQED method has significantly lower expanded uncertainty of 0.26%(k=52)as compared with that of the traditional filter-based method of 0.42%(k=52).Furthermore,when filtered photometers that measure LED lighting are calibrated using LED lamps as calibration sources instead of incandescent lamps,a significant decrease in the uncertainty related to the spectral mismatch correction can be obtained.The maximum spectral mismatch errors of LED measurements decreased on average by a factor of 3 when switching from an incandescent lamp to an LED calibration source.展开更多
AIM:To investigate the correlations between selfreported symptoms of irritable bowel syndrome(IBS) and the gastrointestinal(GI) microbiota composition.METHODS:Fecal samples were collected from a total of 44 subjects d...AIM:To investigate the correlations between selfreported symptoms of irritable bowel syndrome(IBS) and the gastrointestinal(GI) microbiota composition.METHODS:Fecal samples were collected from a total of 44 subjects diagnosed with IBS.Their symptoms were monitored with a validated inflammatory bowel disease questionnaire adjusted for IBS patients.Thirteen quantitative real-time polymerase chain reaction assays were applied to evaluate the GI microbiota composition.Eubacteria and GI bacterial genera(Bifidobacterium,Lactobacillus and Veillonella),groups(Clostridium coccoides/Eubacterium rectale,Desulfovibrio desulfuricans) and distinct bacterial phylotypes [closest 16S rDNA sequence resemblance to species Bifidobacterium catenulatum,Clostridium cocleatum,Collinsella aerofaciens(C.aerofaciens),Coprococcus eutactus(C.eutactus),Ruminococcus torques and Streptococcus bovis ] with a suspected association with IBS were quantified.Correlations between quantities or presence/absence data of selected bacterial groups or phylotypes and various IBSrelated symptoms were investigated.RESULTS:Associations were observed between subjects' self-reported symptoms and the presence or quantities of certain GI bacteria.A Ruminococcus torques(R.torques)-like(94% similarity in 16S rRNA gene sequence) phylotype was associated with severity of bowel symptoms.Furthermore,among IBS subjects with R.torques 94% detected,the amounts of C.cocleatum 88%,C.aerofaciens-like and C.eutactus 97% phylotypes were significantly reduced.Interesting observations were also made concerning the effect of a subject's weight on GI microbiota with regard to C.aerofaciens like phylotype,Bifidobacterium spp.and Lactobacillus spp.CONCLUSION:Bacteria seemingly affecting the symptom scores are unlikely to be the underlying cause or cure of IBS,but they may serve as biomarkers of the condition.展开更多
A numerical study of stress distribution and fatigue behavior in terms of the effect of voids adjacent to inclusions was conducted with finite element modeling simulations under different assumptions.Fatigue mechanism...A numerical study of stress distribution and fatigue behavior in terms of the effect of voids adjacent to inclusions was conducted with finite element modeling simulations under different assumptions.Fatigue mechanisms were also analyzed accordingly.The results showed that the effects of inclusions on fatigue life will distinctly decrease if the mechanical properties are close to those of the steel matrix.For the inclusions,which are tightly bonded with the steel matrix,when the Young’s modulus is larger than that of the steel matrix,the stress will concentrate inside the inclusion;otherwise,the stress will concentrate in the steel matrix.If voids exist on the interface between inclusions and the steel matrix,their effects on the fatigue process differ with their positions relative to the inclusions.The void on one side of an inclusion perpendicular to the fatigue loading direction will aggravate the effect of inclusions on fatigue behavior and lead to a sharp stress concentration.The void on the top of inclusion along the fatigue loading direction will accelerate the debonding between the inclusion and steel matrix.展开更多
AIM:To study the association between Helicobacter pylori(H.pylori)infection and autoimmune type atrophic gastritis. METHODS:Twenty-three patients with different grades of atrophic gastritis were analysed using enzyme ...AIM:To study the association between Helicobacter pylori(H.pylori)infection and autoimmune type atrophic gastritis. METHODS:Twenty-three patients with different grades of atrophic gastritis were analysed using enzyme immunoassay-based serology,immunoblot-based serology,and histology to reveal a past or a present H.pylori infection.In addition,serum markers for gastric atrophy(pepsinogenⅠ,pepsinogenⅠ/Ⅱand gastrin)and autoimmunity[parietal cell antibodies(PCA), and intrinsic factor(IF),antibodies]were determined. RESULTS:Of the 14 patients with severe gastricatrophy,as demonstrated by histology and serum markers,and no evidence for an ongoing H.pylori infection,eight showed H.pylori antibodies by immunoblotting.All eight had elevated PCA and 4/8 also had IF antibodies.Of the six immunoblot-negative patients with severe corpus atrophy,PCA and IF antibodies were detected in four.Among the patients with low to moderate grade atrophic gastritis(all except one with an ongoing H.pylori infection),serum markers for gastric atrophy and autoimmunity were seldom detected.However,one H.pylori negative patient with mild atrophic gastritis had PCA and IF antibodies suggestive of a pre-atrophic autoimmune gastritis. CONCLUSION:Signs of H.pylori infection in autoimmune gastritis,and positive autoimmune serum markers in H.pylori gastritis suggest an etiological role for H.pylori in autoimmune gastritis.展开更多
We propose a simple method for the efficient and rapid synthesis of one-dimensional hematite(α-Fe_(2)O_(3))nanostructures based on electrical resistive heating of iron wire under ambient conditions.Typically,1-5μm l...We propose a simple method for the efficient and rapid synthesis of one-dimensional hematite(α-Fe_(2)O_(3))nanostructures based on electrical resistive heating of iron wire under ambient conditions.Typically,1-5μm longα-Fe_(2)O_(3)nanowires were synthesized on a time scale of seconds at temperatures of around 700℃.The morphology,structure,and mechanism of formation of the nanowires were studied by scanning and transmission electron microscopies,energy dispersive X-ray spectroscopy,X-ray photoelectron spectroscopy,and Raman techniques.A nanowire growth mechanism based on diffusion of iron ions to the surface through grain boundaries and to the growing wire tip through stacking fault defects and due to surface diffusion is proposed.展开更多
The light-matter interaction in materials is of remarkable interest for various photonic and optoelectronic applications,which is intrinsically determined by the bandgap of the materials involved.To extend the applica...The light-matter interaction in materials is of remarkable interest for various photonic and optoelectronic applications,which is intrinsically determined by the bandgap of the materials involved.To extend the applications beyond the bandgap limit,it is of great significance to study the light-matter interaction below the material bandgap.Here,we report the ultrafast transient absorption of monolayer molybdenum disulfide in its sub-bandgap region from-0.86 pm to 1.4 pm.Even though this spectral range is below the bandgap,we observe a significant absorbance enhancement up to-4.2%in the monolayer molybdenum disulfide(comparable to its absorption within the bandgap region)due to pump-induced absorption by the excited carrier states.The different rise times of the transient absorption at different wavelengths indicate the various contributions of the different carrier states(i.e.,real carrier states in the short-wavelength region of~<1μm,and exciton states in the long wavelength region of~>1μm).Our results elucidate the fundamental understanding regarding the optical properties,excited carrier states,and carrier dynamics in the technologically important near-infrared region,which potentially leads to various photonic and optoelectronic applications(e.g„excited-state-based photodetectors and modulators)of two-dimensional materials and their heterostructures beyond their intrinsic bandgap limitations.展开更多
Multi-material laser-based powder bed fusion (PBF-LB) allows manufacturing of parts with 3-dimensional gradient and additional functionality in a single step. This research focuses on the combination of thermally-cond...Multi-material laser-based powder bed fusion (PBF-LB) allows manufacturing of parts with 3-dimensional gradient and additional functionality in a single step. This research focuses on the combination of thermally-conductive CuCr1Zr with hard M300 tool steel.Two interface configurations of M300 on CuCr1Zr and CuCr1Zr on M300 were investigated. Ultra-fine grains form at the interface due to the low mutual solubility of Cu and steel. The material mixing zone size is dependent on the configurations and tunable in the range of0.1–0.3 mm by introducing a separate set of parameters for the interface layers. Microcracks and pores mainly occur in the transition zone.Regardless of these defects, the thermal diffusivity of bimetallic parts with 50vol% of CuCr1Zr significantly increases by 70%–150%compared to pure M300. The thermal diffusivity of CuCr1Zr and the hardness of M300 steel can be enhanced simultaneously by applying the aging heat treatment.展开更多
One of the key factors in a profitable open-pit mine is the efficiency of the waste disposal system. Using GPS-technology, the truck-dispatching decisions can be made in real-time but the chosen strategy has a crucial...One of the key factors in a profitable open-pit mine is the efficiency of the waste disposal system. Using GPS-technology, the truck-dispatching decisions can be made in real-time but the chosen strategy has a crucial role. Therefore, finding the optimal dispatching strategy for truck-shovel operations is extremely important. Dispatching strategies have been reported in the literature, but the comparison of these strategies is still missing. This paper illustrates the differences between the strategies by conducting a stochastic simulation study based on the data gathered from an actual mine. The findings underline the importance of the global vision in dispatching decisions.展开更多
Catalytic activity of the hydrogen evolution reaction on nanoclusters depends on diverse adsorption site structures.Machine learning reduces the cost for modelling those sites with the aid of descriptors.We analysed t...Catalytic activity of the hydrogen evolution reaction on nanoclusters depends on diverse adsorption site structures.Machine learning reduces the cost for modelling those sites with the aid of descriptors.We analysed the performance of state-of-the-art structural descriptors Smooth Overlap of Atomic Positions,Many-Body Tensor Representation and Atom-Centered Symmetry Functions while predicting the hydrogen adsorption(free)energy on the surface of nanoclusters.The 2D-material molybdenum disulphide and the alloy copper–gold functioned as test systems.Potential energy scans of hydrogen on the cluster surfaces were conducted to compare the accuracy of the descriptors in kernel ridge regression.By having recourse to data sets of 91 molybdenum disulphide clusters and 24 copper–gold clusters,we found that the mean absolute error could be reduced by machine learning on different clusters simultaneously rather than separately.The adsorption energy was explained by the local descriptor Smooth Overlap of Atomic Positions,combining it with the global descriptor Many-Body Tensor Representation did not improve the overall accuracy.We concluded that fitting of potential energy surfaces could be reduced significantly by merging data from different nanoclusters.展开更多
This work made use of the Aalto University Otanano-Nanomicroscopy Center and RAMI infrastructures.Financial support from Business Finland NextGenBat[grant number 211849]is greatly acknowledged.The tomography experimen...This work made use of the Aalto University Otanano-Nanomicroscopy Center and RAMI infrastructures.Financial support from Business Finland NextGenBat[grant number 211849]is greatly acknowledged.The tomography experiment was performed at the beamline ID16B of the European Synchrotron Radiation Facility(ESRF),Grenoble,France,in the frame of proposal CH-6644.The patent titled“Stabilized Positive Electrode Material to Enable High Energy and Power Density Lithium-Ion Batteries”(IPD3173)is pertinent to this manuscript.It was filed by Zahra Ahaliabadeh and Tanja Kallio,and the patent rights are held by Aalto University.展开更多
The basic mechanism and kinetics of the transformation process of alumina inclusions in steel was reported when calcium introduced into the steel by wire feeding orpowder injection. To clarify the mechanisms model, ex...The basic mechanism and kinetics of the transformation process of alumina inclusions in steel was reported when calcium introduced into the steel by wire feeding orpowder injection. To clarify the mechanisms model, experiments were performed by studying reactions between AltOs and CaO in a laboratory furnace and by performing calcium treatments in an 8kg induction furnace for Al deoxidised melt. The phases formed during the reaction between Al2O3 and CaO were examined by SEM-EDS （scanning electron microscope-energy dispersive spectrometer）, and the reaction sequence of Al2O3=〉 CA6=〉 CA2 =〉 CA =〉 CAx（l） was discussed in term of the experimental observations. The kinetics of the reaction of calcium with alumina inclusions were simulated by immersing alumina plates in a Ca treated steel melt in the induction furnace. Results were compared with observations of real inclusion transformation. A kinetic model was proposed based on the results.展开更多
Clustering is used to gain an intuition of the struc tures in the data.Most of the current clustering algorithms pro duce a clustering structure even on data that do not possess such structure.In these cases,the algor...Clustering is used to gain an intuition of the struc tures in the data.Most of the current clustering algorithms pro duce a clustering structure even on data that do not possess such structure.In these cases,the algorithms force a structure in the data instead of discovering one.To avoid false structures in the relations of data,a novel clusterability assessment method called density-based clusterability measure is proposed in this paper.I measures the prominence of clustering structure in the data to evaluate whether a cluster analysis could produce a meaningfu insight to the relationships in the data.This is especially useful in time-series data since visualizing the structure in time-series data is hard.The performance of the clusterability measure is evalu ated against several synthetic data sets and time-series data sets which illustrate that the density-based clusterability measure can successfully indicate clustering structure of time-series data.展开更多
Neurotrophic factors as a therapeutic approach in neurodegenerative diseases:A major unmet need in the field of central nervous system diseases is disease-modifying treatments.While for decades there have been various...Neurotrophic factors as a therapeutic approach in neurodegenerative diseases:A major unmet need in the field of central nervous system diseases is disease-modifying treatments.While for decades there have been various symptomatic treatments available to alleviate the symptoms of the disease,disease-modification,i.e.treatments that stop,significantly delay,or reverse the progression of the disease,has been turned out to a difficult goal to achieve.展开更多
Condition monitoring of the insulating system within power transformers has a massive importance according to the electrical utilities.Dissolved gas analysis(DGA)is frequently used for this purpose.However,DGA lacks t...Condition monitoring of the insulating system within power transformers has a massive importance according to the electrical utilities.Dissolved gas analysis(DGA)is frequently used for this purpose.However,DGA lacks the necessary level of accuracy to identify all equipment faults,particularly in their initial stages of degradation.Also,it does not have the capability for real-time monitoring and relies on manual sampling and laboratory testing,causing potential delays in fault identification.Additionally,the interpretation of DGA data necessitates specialised expertise,which may pose difficulties for smaller entities that have limited access to resources.Therefore,the contribution of this research is to use infrared spectroscopy measurements as a new effective technique substituting the DGA method for fault diagnosis in insulating oil.The inception faults that were considered in this study were the electrical fault(discharges of high energy)and the thermal fault(300°C<Temperature<700°C).Regarding that,two test cells were crafted especially for serving the simulation processes inside the laboratory for both types of inception faults.Subsequently,six samples of pure paraffinic mineral oil were taken to be degraded in the laboratory.Following that,all of them besides another sample that were not subjected to any kind of faults were taken to be examined by Fourier transform infrared(FTIR)spectroscopy to obtain an overview of the oil's behaviour in each fault case.After that,the FTIR analysis was initially verified utilising the DGA method.Then,for further affirmation,the dielectric dissipation factor(DDF)for all samples was measured.In the final analysis,the verification tests provide experimental evidence about the outperformance of this new optical technique in detecting the transformer's inception faults in addition to proving its potential for being a superior alternative to the well-known traditional diagnostic techniques.展开更多
Permissionless blockchain,as a kind of distributed ledger,has gained considerable attention because of its openness,transparency,decentralization,and immutability.Currently,permissionless blockchain has shown a good a...Permissionless blockchain,as a kind of distributed ledger,has gained considerable attention because of its openness,transparency,decentralization,and immutability.Currently,permissionless blockchain has shown a good application prospect in many fields,from the initial cryptocurrency to the Internet of Things(IoT)and Vehicular Ad-Hoc Networking(VANET),which is considered as the beginning of rewriting our digital infrastructure.However,blockchain confronts some privacy risks that hinder its practical applications.Though numerous surveys reviewed the privacy preservation in blockchain,they failed to reveal the latest advances,nor have they been able to conduct a unified standard comprehensive classification of the privacy protection of permissionless blockchain.Therefore,in this paper,we analyze the specific characteristics of permissionless blockchain,summarize the potential privacy threats,and investigate the unique privacy requirements of blockchain.Existing privacy preservation technologies are carefully surveyed and evaluated based on our proposed evaluation criteria.We finally figure out open research issues as well as future research directions from the perspective of privacy issues.展开更多
基金Supported by The Finnish Funding Agency for Technologyand Innovation,Tekes,grants No.945/401/00 and 40160/05the Finnish Graduate School of Applied Biosciences,the Academy of Finland,Grant No.214 157the Centre of Excellence on Microbial Food Safety Research,Academy of Finland
文摘AIM:To study whether selected bacterial 16S ribosomal RNA(rRNA)gene phylotypes are capable of disting- uishing irritable bowel syndrome(IBS). METHODS:The faecal microbiota of twenty volunteers with IBS,subdivided into eight diarrhoea-predominant (IBS-D),eight constipation-predominant(IBS-C)and four mixed symptom-subtype(IBS-M)IBS patients,and fifteen control subjects,were analysed at three time-points with a set of fourteen quantitative real-timepolymerase chain reaction assays.All assays targeted 16S rRNA gene phylotypes putatively associated with IBS,based on 16S rRNA gene library sequence analysis. The target phylotypes were affiliated with Actinobac-teria,Bacteroidetes and Firmicutes.Eight of the target phylotypes had less than 95%similarity to cultured bacterial species according to their 16S rRNA gene sequence.The data analyses were made with repeated-measures ANCOVA-type modelling of the data and principle component analysis(PCA)with linear mixed-effects models applied to the principal component scores. RESULTS:Bacterial phylotypes Clostridium cocleatum 88%,Clostridium thermosuccinogenes 85%,Coprobacillus catenaformis 91%,Ruminococcus bromii-like, Ruminococcus torques 91%,and R.torques 93%were detected from all samples analysed.A multivariate analysis of the relative quantities of all 14 bacterial 16S rRNA gene phylotypes suggested that the intestinal microbiota of the IBS-D patients differed from other sample groups.The PCA on the first principal component(PC1),explaining 30.36%of the observed variation in the IBS-D patient group,was significantly altered from all other sample groups(IBS-D vs control, P=0.01;IBS-D vs IBS-M,P=0.00;IBS-D vs IBS-C, P=0.05).Significant differences were also observed in the levels of distinct phylotypes using relative values in proportion to the total amount of bacteria.A phy- lotype with 85%similarity to C.thermosuccinogenes was quantified in significantly different quantities among the IBS-D and control subjects(-4.08±0.90 vs -3.33±1.16,P=0.04)and IBS-D and IBS-M subjects
文摘In this article we propose to facilitate local peer-to-peer communication by a Device-to-Device (D2D) radio that operates as an underlay network to an IMT-Advanced cellular network. It is expected that local services may utilize mobile peer-to-peer communication instead of central server based communication for rich mul-timedia services. The main challenge of the underlay radio in a multi-cell environment is to limit the inter-ference to the cellular network while achieving a reasonable link budget for the D2D radio. We propose a novel power control mechanism for D2D connections that share cellular uplink resources. The mechanism limits the maximum D2D transmit power utilizing cellular power control information of the devices in D2D communication. Thereby it enables underlaying D2D communication even in interference-limited networks with full load and without degrading the performance of the cellular network. Secondly, we study a single cell scenario consisting of a device communicating with the base station and two devices that communicate with each other. The results demonstrate that the D2D radio, sharing the same resources as the cellular net-work, can provide higher capacity (sum rate) compared to pure cellular communication where all the data is transmitted through the base station.
基金National Key R&D Program of China(No.2018YFB1600200,2021YFB1600200)National Natural Science Foundation of China(No.51608457,51778038,51808016,51808403,51908057,51908072,51908165,51908331,52008029,52008069,52078018,52078025,52078049,52078209,52108403,52122809,52178417)+9 种基金Marie Sk?odowska-Curie Individual Fellowships of the European Commission’s Horizon 2020 programme(No.101024139)Natural Science Foundation of Heilongjiang Province(No.JJ2020ZD0015)China Postdoctoral Science Foundation funded project(No.BX20180088)Research Capability Enhancement Program for Young Professors of Beijing University of Civil Engineering and Architecture(No.02080921021)Young Scholars of Beijing Talent Program(No.02082721009)Beijing Municipal Natural Science Foundation and Beijing Municipal Education Commission(No.KZ201910016017)German Research Foundation(No.OE 514/15-1(459436571))Fundamental Research Funds for the Central Universities(No.2020kfyXJJS127)Marie Sk?odowska-Curie Individual Fellowships of the European Commission’s Horizon 2020 Programme(No.101030767)Research Fund for High Level Talent Program(No.22120210108)。
文摘Sustainable and resilient pavement infrastructure is critical for current economic and environmental challenges.In the past 10 years,the pavement infrastructure strongly supports the rapid development of the global social economy.New theories,new methods,new technologies and new materials related to pavement engineering are emerging.Deterioration of pavement infrastructure is a typical multi-physics problem.Because of actual coupled behaviors of traffic and environmental conditions,predictions of pavement service life become more and more complicated and require a deep knowledge of pavement material analysis.In order to summarize the current and determine the future research of pavement engineering,Journal of Traffic and Transportation Engineering(English Edition)has launched a review paper on the topic of"New innovations in pavement materials and engineering:A review on pavement engineering research 2021".Based on the joint-effort of 43 scholars from 24 well-known universities in highway engineering,this review paper systematically analyzes the research status and future development direction of 5 major fields of pavement engineering in the world.The content includes asphalt binder performance and modeling,mixture performance and modeling of pavement materials,multi-scale mechanics,green and sustainable pavement,and intelligent pavement.Overall,this review paper is able to provide references and insights for researchers and engineers in the field of pavement engineering.
基金The research leading to these results has received partial funding from the European Metrology Research Programme(EMRP)project SIB57‘New Primary Standards and Traceability for Radiometry’The EMRP is jointly funded by the EMRP participating countries within EURAMET and the European Union.
文摘Light emitting diode(LED)lighting is becoming more and more popular,as incandescent lamps are being phased out globally.LEDs have several advantages over incandescent lamps,including energy efficiency,robustness,long lifetime,and good temporal stability.The three latter features make LEDs attractive candidates as new photometric standards.Because the spectra of white LEDs are limited to the visible wavelength range,a novel method for the realization of photometric units based on the predictable quantum efficient detector(PQED)can be utilized.The method eliminates the need of photometric filters that are traditionally used in photometry,and instead relies on carrying out the photometric weighting numerically based on the measured relative spectrum of the source.The PQED-based realization simplifies the traceability chain of photometric measurements significantly as compared with the traditional filter-based method.The measured illuminance values of a white LED deviate by only 0.03%when determined by the new and the traditional methods.The new PQED method has significantly lower expanded uncertainty of 0.26%(k=52)as compared with that of the traditional filter-based method of 0.42%(k=52).Furthermore,when filtered photometers that measure LED lighting are calibrated using LED lamps as calibration sources instead of incandescent lamps,a significant decrease in the uncertainty related to the spectral mismatch correction can be obtained.The maximum spectral mismatch errors of LED measurements decreased on average by a factor of 3 when switching from an incandescent lamp to an LED calibration source.
基金Supported by The Finnish Funding Agency for Technology and Innovation (Tekes grant No 40039/03)the Finnish Graduate School on Applied Biosciences and the Centre of Excellence on Microbial Food Safety Research,Academy of Finland
文摘AIM:To investigate the correlations between selfreported symptoms of irritable bowel syndrome(IBS) and the gastrointestinal(GI) microbiota composition.METHODS:Fecal samples were collected from a total of 44 subjects diagnosed with IBS.Their symptoms were monitored with a validated inflammatory bowel disease questionnaire adjusted for IBS patients.Thirteen quantitative real-time polymerase chain reaction assays were applied to evaluate the GI microbiota composition.Eubacteria and GI bacterial genera(Bifidobacterium,Lactobacillus and Veillonella),groups(Clostridium coccoides/Eubacterium rectale,Desulfovibrio desulfuricans) and distinct bacterial phylotypes [closest 16S rDNA sequence resemblance to species Bifidobacterium catenulatum,Clostridium cocleatum,Collinsella aerofaciens(C.aerofaciens),Coprococcus eutactus(C.eutactus),Ruminococcus torques and Streptococcus bovis ] with a suspected association with IBS were quantified.Correlations between quantities or presence/absence data of selected bacterial groups or phylotypes and various IBSrelated symptoms were investigated.RESULTS:Associations were observed between subjects' self-reported symptoms and the presence or quantities of certain GI bacteria.A Ruminococcus torques(R.torques)-like(94% similarity in 16S rRNA gene sequence) phylotype was associated with severity of bowel symptoms.Furthermore,among IBS subjects with R.torques 94% detected,the amounts of C.cocleatum 88%,C.aerofaciens-like and C.eutactus 97% phylotypes were significantly reduced.Interesting observations were also made concerning the effect of a subject's weight on GI microbiota with regard to C.aerofaciens like phylotype,Bifidobacterium spp.and Lactobacillus spp.CONCLUSION:Bacteria seemingly affecting the symptom scores are unlikely to be the underlying cause or cure of IBS,but they may serve as biomarkers of the condition.
基金This work was financially supported by the Fundamental Research Funds for the Central Universities(No.FRF-TP-20-026A1)the China Postdoctoral Science Foundation(No.2020M680348)the State Key Laboratory of Advanced Metallurgy Foundation of China(No.41620001).
文摘A numerical study of stress distribution and fatigue behavior in terms of the effect of voids adjacent to inclusions was conducted with finite element modeling simulations under different assumptions.Fatigue mechanisms were also analyzed accordingly.The results showed that the effects of inclusions on fatigue life will distinctly decrease if the mechanical properties are close to those of the steel matrix.For the inclusions,which are tightly bonded with the steel matrix,when the Young’s modulus is larger than that of the steel matrix,the stress will concentrate inside the inclusion;otherwise,the stress will concentrate in the steel matrix.If voids exist on the interface between inclusions and the steel matrix,their effects on the fatigue process differ with their positions relative to the inclusions.The void on one side of an inclusion perpendicular to the fatigue loading direction will aggravate the effect of inclusions on fatigue behavior and lead to a sharp stress concentration.The void on the top of inclusion along the fatigue loading direction will accelerate the debonding between the inclusion and steel matrix.
文摘AIM:To study the association between Helicobacter pylori(H.pylori)infection and autoimmune type atrophic gastritis. METHODS:Twenty-three patients with different grades of atrophic gastritis were analysed using enzyme immunoassay-based serology,immunoblot-based serology,and histology to reveal a past or a present H.pylori infection.In addition,serum markers for gastric atrophy(pepsinogenⅠ,pepsinogenⅠ/Ⅱand gastrin)and autoimmunity[parietal cell antibodies(PCA), and intrinsic factor(IF),antibodies]were determined. RESULTS:Of the 14 patients with severe gastricatrophy,as demonstrated by histology and serum markers,and no evidence for an ongoing H.pylori infection,eight showed H.pylori antibodies by immunoblotting.All eight had elevated PCA and 4/8 also had IF antibodies.Of the six immunoblot-negative patients with severe corpus atrophy,PCA and IF antibodies were detected in four.Among the patients with low to moderate grade atrophic gastritis(all except one with an ongoing H.pylori infection),serum markers for gastric atrophy and autoimmunity were seldom detected.However,one H.pylori negative patient with mild atrophic gastritis had PCA and IF antibodies suggestive of a pre-atrophic autoimmune gastritis. CONCLUSION:Signs of H.pylori infection in autoimmune gastritis,and positive autoimmune serum markers in H.pylori gastritis suggest an etiological role for H.pylori in autoimmune gastritis.
基金the Academy of Finland(project numbers 128445 and 128495)P.R.M.acknowledges Finnish National Graduate School in Nanoscience(NGS-NANO)S.D.S.thanks the European Commission for financial support through a Marie Curie Individual Fellowship(MIF1-CT-2005-022110).
文摘We propose a simple method for the efficient and rapid synthesis of one-dimensional hematite(α-Fe_(2)O_(3))nanostructures based on electrical resistive heating of iron wire under ambient conditions.Typically,1-5μm longα-Fe_(2)O_(3)nanowires were synthesized on a time scale of seconds at temperatures of around 700℃.The morphology,structure,and mechanism of formation of the nanowires were studied by scanning and transmission electron microscopies,energy dispersive X-ray spectroscopy,X-ray photoelectron spectroscopy,and Raman techniques.A nanowire growth mechanism based on diffusion of iron ions to the surface through grain boundaries and to the growing wire tip through stacking fault defects and due to surface diffusion is proposed.
基金support from Academy of Finland(Grant Nos.314810,333982,336144 and 336818)Academy of Finland Flagship Program(Grant No 320167,PREIN)+2 种基金the European Union's Horizon 2020 research and innovation program(Grant No.820423,S2QUIP)the EU H2020-MSCA-RISE-872049(IPN-Bio)ERC(Grant No 834742).
文摘The light-matter interaction in materials is of remarkable interest for various photonic and optoelectronic applications,which is intrinsically determined by the bandgap of the materials involved.To extend the applications beyond the bandgap limit,it is of great significance to study the light-matter interaction below the material bandgap.Here,we report the ultrafast transient absorption of monolayer molybdenum disulfide in its sub-bandgap region from-0.86 pm to 1.4 pm.Even though this spectral range is below the bandgap,we observe a significant absorbance enhancement up to-4.2%in the monolayer molybdenum disulfide(comparable to its absorption within the bandgap region)due to pump-induced absorption by the excited carrier states.The different rise times of the transient absorption at different wavelengths indicate the various contributions of the different carrier states(i.e.,real carrier states in the short-wavelength region of~<1μm,and exciton states in the long wavelength region of~>1μm).Our results elucidate the fundamental understanding regarding the optical properties,excited carrier states,and carrier dynamics in the technologically important near-infrared region,which potentially leads to various photonic and optoelectronic applications(e.g„excited-state-based photodetectors and modulators)of two-dimensional materials and their heterostructures beyond their intrinsic bandgap limitations.
基金supported by VTT Technical Research Centre of Finland,Aalto University,Aerosint SA,and partially from European Union Horizon 2020 (No.768775)。
文摘Multi-material laser-based powder bed fusion (PBF-LB) allows manufacturing of parts with 3-dimensional gradient and additional functionality in a single step. This research focuses on the combination of thermally-conductive CuCr1Zr with hard M300 tool steel.Two interface configurations of M300 on CuCr1Zr and CuCr1Zr on M300 were investigated. Ultra-fine grains form at the interface due to the low mutual solubility of Cu and steel. The material mixing zone size is dependent on the configurations and tunable in the range of0.1–0.3 mm by introducing a separate set of parameters for the interface layers. Microcracks and pores mainly occur in the transition zone.Regardless of these defects, the thermal diffusivity of bimetallic parts with 50vol% of CuCr1Zr significantly increases by 70%–150%compared to pure M300. The thermal diffusivity of CuCr1Zr and the hardness of M300 steel can be enhanced simultaneously by applying the aging heat treatment.
文摘One of the key factors in a profitable open-pit mine is the efficiency of the waste disposal system. Using GPS-technology, the truck-dispatching decisions can be made in real-time but the chosen strategy has a crucial role. Therefore, finding the optimal dispatching strategy for truck-shovel operations is extremely important. Dispatching strategies have been reported in the literature, but the comparison of these strategies is still missing. This paper illustrates the differences between the strategies by conducting a stochastic simulation study based on the data gathered from an actual mine. The findings underline the importance of the global vision in dispatching decisions.
基金The work was supported by the World Premier International Research Center Initiative(WPI),MEXT,Japan and the European Union’s Horizon 2020 research and innovation program under grant agreement no.676580 NOMAD,a European Center of Excellence and no.686053 CRITCAT.
文摘Catalytic activity of the hydrogen evolution reaction on nanoclusters depends on diverse adsorption site structures.Machine learning reduces the cost for modelling those sites with the aid of descriptors.We analysed the performance of state-of-the-art structural descriptors Smooth Overlap of Atomic Positions,Many-Body Tensor Representation and Atom-Centered Symmetry Functions while predicting the hydrogen adsorption(free)energy on the surface of nanoclusters.The 2D-material molybdenum disulphide and the alloy copper–gold functioned as test systems.Potential energy scans of hydrogen on the cluster surfaces were conducted to compare the accuracy of the descriptors in kernel ridge regression.By having recourse to data sets of 91 molybdenum disulphide clusters and 24 copper–gold clusters,we found that the mean absolute error could be reduced by machine learning on different clusters simultaneously rather than separately.The adsorption energy was explained by the local descriptor Smooth Overlap of Atomic Positions,combining it with the global descriptor Many-Body Tensor Representation did not improve the overall accuracy.We concluded that fitting of potential energy surfaces could be reduced significantly by merging data from different nanoclusters.
基金Financial support from Business Finland NextGenBat[grant number 211849]is greatly acknowledged.
文摘This work made use of the Aalto University Otanano-Nanomicroscopy Center and RAMI infrastructures.Financial support from Business Finland NextGenBat[grant number 211849]is greatly acknowledged.The tomography experiment was performed at the beamline ID16B of the European Synchrotron Radiation Facility(ESRF),Grenoble,France,in the frame of proposal CH-6644.The patent titled“Stabilized Positive Electrode Material to Enable High Energy and Power Density Lithium-Ion Batteries”(IPD3173)is pertinent to this manuscript.It was filed by Zahra Ahaliabadeh and Tanja Kallio,and the patent rights are held by Aalto University.
文摘The basic mechanism and kinetics of the transformation process of alumina inclusions in steel was reported when calcium introduced into the steel by wire feeding orpowder injection. To clarify the mechanisms model, experiments were performed by studying reactions between AltOs and CaO in a laboratory furnace and by performing calcium treatments in an 8kg induction furnace for Al deoxidised melt. The phases formed during the reaction between Al2O3 and CaO were examined by SEM-EDS （scanning electron microscope-energy dispersive spectrometer）, and the reaction sequence of Al2O3=〉 CA6=〉 CA2 =〉 CA =〉 CAx（l） was discussed in term of the experimental observations. The kinetics of the reaction of calcium with alumina inclusions were simulated by immersing alumina plates in a Ca treated steel melt in the induction furnace. Results were compared with observations of real inclusion transformation. A kinetic model was proposed based on the results.
文摘Clustering is used to gain an intuition of the struc tures in the data.Most of the current clustering algorithms pro duce a clustering structure even on data that do not possess such structure.In these cases,the algorithms force a structure in the data instead of discovering one.To avoid false structures in the relations of data,a novel clusterability assessment method called density-based clusterability measure is proposed in this paper.I measures the prominence of clustering structure in the data to evaluate whether a cluster analysis could produce a meaningfu insight to the relationships in the data.This is especially useful in time-series data since visualizing the structure in time-series data is hard.The performance of the clusterability measure is evalu ated against several synthetic data sets and time-series data sets which illustrate that the density-based clusterability measure can successfully indicate clustering structure of time-series data.
基金supported by Herantis Pharma Plc and the European Innovation Council(grant acronym ReTreatPD).
文摘Neurotrophic factors as a therapeutic approach in neurodegenerative diseases:A major unmet need in the field of central nervous system diseases is disease-modifying treatments.While for decades there have been various symptomatic treatments available to alleviate the symptoms of the disease,disease-modification,i.e.treatments that stop,significantly delay,or reverse the progression of the disease,has been turned out to a difficult goal to achieve.
文摘Condition monitoring of the insulating system within power transformers has a massive importance according to the electrical utilities.Dissolved gas analysis(DGA)is frequently used for this purpose.However,DGA lacks the necessary level of accuracy to identify all equipment faults,particularly in their initial stages of degradation.Also,it does not have the capability for real-time monitoring and relies on manual sampling and laboratory testing,causing potential delays in fault identification.Additionally,the interpretation of DGA data necessitates specialised expertise,which may pose difficulties for smaller entities that have limited access to resources.Therefore,the contribution of this research is to use infrared spectroscopy measurements as a new effective technique substituting the DGA method for fault diagnosis in insulating oil.The inception faults that were considered in this study were the electrical fault(discharges of high energy)and the thermal fault(300°C<Temperature<700°C).Regarding that,two test cells were crafted especially for serving the simulation processes inside the laboratory for both types of inception faults.Subsequently,six samples of pure paraffinic mineral oil were taken to be degraded in the laboratory.Following that,all of them besides another sample that were not subjected to any kind of faults were taken to be examined by Fourier transform infrared(FTIR)spectroscopy to obtain an overview of the oil's behaviour in each fault case.After that,the FTIR analysis was initially verified utilising the DGA method.Then,for further affirmation,the dielectric dissipation factor(DDF)for all samples was measured.In the final analysis,the verification tests provide experimental evidence about the outperformance of this new optical technique in detecting the transformer's inception faults in addition to proving its potential for being a superior alternative to the well-known traditional diagnostic techniques.
基金The work is supported in part by the National Natural Science Foundation of China under Grants 61672410 and 61802293the Academy of Finland under Grants 308087,314203 and 335262+5 种基金the Key Lab of Information Network Security,Ministry of Public Security under grant No.C18614the open grant of the Tactical Data Link Lab of the 20th Research Institute of China Electronics Technology Group Corporation,P.R.China under grant CLDL-20182119the National Postdoctoral Program for Innovative Talents under grant BX20180238the Project funded by China Postdoctoral Science Foundation under grant 2018M633461the Shaanxi Innovation Team project under grant 2018TD-007the 111 project under grant B16037.
文摘Permissionless blockchain,as a kind of distributed ledger,has gained considerable attention because of its openness,transparency,decentralization,and immutability.Currently,permissionless blockchain has shown a good application prospect in many fields,from the initial cryptocurrency to the Internet of Things(IoT)and Vehicular Ad-Hoc Networking(VANET),which is considered as the beginning of rewriting our digital infrastructure.However,blockchain confronts some privacy risks that hinder its practical applications.Though numerous surveys reviewed the privacy preservation in blockchain,they failed to reveal the latest advances,nor have they been able to conduct a unified standard comprehensive classification of the privacy protection of permissionless blockchain.Therefore,in this paper,we analyze the specific characteristics of permissionless blockchain,summarize the potential privacy threats,and investigate the unique privacy requirements of blockchain.Existing privacy preservation technologies are carefully surveyed and evaluated based on our proposed evaluation criteria.We finally figure out open research issues as well as future research directions from the perspective of privacy issues.
