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The Variation of Microbial Communities in a Depth Profile of an Acidic,Nutrient-Poor Boreal Bog in Southwestern finland

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Open Journal of Ecology 2014年第13期4卷 832-859页

作者： Irina Tsitko Merja Lusa Jukka Lehto Lauri Parviainen Ari T.K.Ikonen Anne-Maj Lahdenpera Malin Bomberg VTT Technical research centre of finland EspooFinland Laboratory of Radiochemistry Department of ChemistryUniversity of HelsinkiHelsinkiFinland Posiva Oy OlkiluotoFinland Environmental research and Assessment EnviroCase Ltd.PoriFinland Saanio&RiekkolaOy HelsinkiFinland

Natural bacterial communities impact the motility of isotopes, such as radionuclides, in the environment. As a result of post glacial crustal rebound radionuclides may escape the deep geological repository for spent nuclear fuel on Olkiluoto Island, finland, and reach surface environments. Lastensuo Bog, a 5300-year-old raised bog in southwestern finland, functions as analogue ecotope for bogs formed in Olkiluoto due to the crustal rebound. A core comprising the depth profile (0 - 7 m depth) of the bog including surface Sphagnum moss, peat and bottom clay was obtained using a stainless steel corer. High throughput sequencing was used to characterize the bacterial communities throughout the bog’s depth profile. A total of 12,680 bacterial Operational Taxonomic Units (OTUs) (97% sequence similarity) were detected comprising altogether 40 different bacterial phyla. Of these, 13 phyla were present at all depths, accounting for 97% - 99% of the whole bacterial community. The bacterial communities differed notably through the bog’s depth profile, dividing it into five distinct strata: 1) the Sphagnum moss layer;2) 0.5 - 3.7 m;3) 3.7 - 4.0 m;4) 5.5 - 6.0 m deep peat;5) the former seabed clay at 6.5 - 7.0 m depth. Acidobacteria, α- and γ-Proteobacteria dominated the surface community, but in the peat Acidobacteria contributed with up to 85% of the bacterial community. The estimated bacterial population density ranged between 2 × 109 and 5 × 1010 16S rRNA gene copies g-1 dry-weight peat. This study revealed that Lastensuo Bog had a highly diverse bacterial community. Most of the taxonomic groups belonged to thus far poorly characterized and uncultured bacteria with unknown physiological role. However, new insights into the distribution of bacterial taxa and their putative roles in organic carbon break down within the bog ecosystem have been obtained and an important baseline for further studies has been established.

关键词： Ombotrophic Bog Peat Sequencing Bacterial Community

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Elevated pro-inflammatory and lipotoxic mucosal lipids characterise irritable bowel syndrome

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World Journal of Gastroenterology 2009年第48期15卷 6068-6074页

作者： Kajsa Kajander Eveliina Myllyluoma Sinikka Kyrnpalo Martin Rasmussen Pentti Sipponen Ismo Mattila Tuulikki Seppnen-Laakso Heikki Vapaatalo Matej Orei Riitta Korpela Institute of Biomedicine PharmacologyUniversity of Helsinki Valio Ltd Research Centre Tampere Health centre and Department of Medicine Tampere City Hospital Department of Pathology Jorvi HospitalHelsinki University Central Hospital VTT Technical research centre of finland Foundation for Nutrition research

AIM： To investigate the pathophysiology of irritable bowel syndrome （IBS） by comparing the global mucosal metabolic profiles of IBS patients with those of healthy controls. METHODS： Fifteen IBS patients fulfilling the Rome II criteria, and nine healthy volunteers were included in the study. A combined lipidomics （UPLC/MS） and metabolomics （GC × GC-TOF） approach was used to achieve global metabolic profiles of mucosal biopsies from the ascending colon. RESULTS： Overall, lipid levels were elevated in patients with IBS. The most significant upregulation was seen for pro-inflammatory lysophosphatidylcholines. Other lipid groups that were significantly upregulated in IBS patients were lipotoxic ceramides, glycosphingolipids, and di-and triacylglycerols. Among the meo tabolites, the cyclic ester 2（3H）-furanone was almost 14-fold upregulated in IBS patients compared to healthy subjects （P = 0.03）. CONCLUSION： IBS mucosa is characterised by a distinct pro-inflammatory and lipotoxic metabolic profile. Especially, there was an increase in several lipid species such as lysophospholipids and ceramides.

关键词： Functional gastrointestinal diseases Irritable bowel syndrome Histopathology

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Mid-infrared computational temporal ghost imaging

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Light(Science & Applications) 2024年第6期13卷 1088-1097页

作者： Han Wu Bo Hu Lu Chen Fei Peng Zinan Wang Goery Genty Houkun Liang College of Electronics and Information Engineering Sichuan UniversityChengduSichuan610064China College of Electrical Engineering Sichuan UniversityChengduSichuan610064China Key Lab of Optical Fiber Sensing&Communications University of Electronic Science&Technology of ChinaChengduSichuan611731China Laboratory of Photonics Tampere UniversityFI-33014TampereFinland

Ghost imaging in the time domain allows for reconstructing fast temporal objects using a slow *** technique involves correlating random or pre-programmed probing temporal intensity patterns with the integrated signal measured after modulation by the temporal ***,the implementation of temporal ghost imaging necessitates ultrafast detectors or modulators for measuring or pre-programming the probing intensity patterns,which are not available in all spectral regions especially in the mid-infrared ***,we demonstrate a frequency downconversion temporal ghost imaging scheme that enables to extend the operation regime to arbitrary wavelengths regions where fast modulators and detectors are not *** approach modulates a signal with temporal intensity patterns in the near-infrared and transfers the patterns to an idler via difference-frequency generation in a nonlinear crystal at a wavelength where the temporal object can be *** a proof-of-concept,we demonstrate computational temporal ghost imaging in the mid-infrared with operating wavelength that can be tuned from 3.2 to 4.3μ*** scheme is flexible and can be extended to other *** results introduce new possibilities for scan-free pump-probe imaging and the study of ultrafast dynamics in spectral regions where ultrafast modulation or detection is challenging such as the mid-infrared and THz regions.

关键词： ghost Ghost scheme

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Cellulose structure and lignin distribution in normal and compression wood of the Maidenhair tree(Ginkgo biloba L.)

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Journal of Integrative Plant Biology 2015年第4期57卷 388-395页

作者： Seppo Andersson Yurong Wang Raili P?nni Tuomas H?nninen Marko Mononen Haiqing Ren Ritva Serimaa Pekka Saranp?? Department of Physics University of Helsinki research Institute of Wood Industry Chinese Academy of Forestry Department of Forest Products Technology Aalto UniversitySchool of Chemical Technology VTT Technical research centre of finland Natural Resources Institute finland

We studied in detail the mean micro fibril angle and the width of cellulose crystals from the pith to the bark of a 15-year-old Maidenhair tree（Ginkgo biloba L.）. The orientation of cellulose micro fibrils with respect to the cell axis and the width and length of cellulose crystallites were determined using Xray diffraction. Raman microscopy was used to compare the lignin distribution in the cell wall of normal/opposite and compression wood, which was found near the pith. Ginkgo biloba showed a relatively large mean micro fibril angle,varying between 19° and 39° in the S2 layer, and the average width of cellulose crystallites was 3.1–3.2 nm. Mild compression wood without any intercellular spaces or helical cavities was observed near the pith. Slit-like bordered pit openings and a heavily lignified S2 L layer con firmed the presence of compression wood. Ginkgo biloba showed typical features present in the juvenile wood of conifers. The micro fibril angle remained large over the 14 annual rings. The entire stem disc,with a diameter of 18 cm, was considered to consist of juvenile wood. The properties of juvenile and compression wood as well as the cellulose orientation and crystalline width indicate that the wood formation of G. biloba is similar to that of modern conifers.

关键词： Cellulose structure cell wall compression wood lignin Maidenhair tree microfibril angle

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NOMA-Based Spectrum Sensing for Satellite-Terrestrial Communication

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China Communications 2023年第4期20卷 227-242页

作者： Tianheng Xu Yinjun Xu Ting Zhou Xianfu Chen Honglin Hu Shanghai Advanced research Institute Chinese Academy of SciencesShanghai 201210China Shanghai Frontier lnnovation research Institute Shanghai 201100China School of Microelectronics Shanghai UniversityShanghai 200444China VTT Technical research centre of finland 90570 OuluFinland

With the continuous development of wireless communication technology,the number of access devices continues to soar,which poses a grate challenge to the already scarce spectrum ***,6G will be an era of air-space-terrestrial-sea integration,and satellite spectrum resources are also very tight in the context of giant *** this paper,we propose a Non-Orthogonal Multiple Access(NOMA)based spectrum sensing scheme for the future satellite-terrestrial communication scenarios,and design the transceiver from uplink and downlink scenarios,*** order to better identify the user's transmission status,we obtain the feature values of each user through feature detection to make *** combine these two technologies to design the transceiver architecture and deduce the threshold value of feature detection in the satellite-terrestrial communication *** are performed in each scenario,and the results illustrate that the proposed scheme combining NOMA and spectrum sensing can greatly improve the throughput with a similar detection probability as Orthogonal Multiple Access(OMA).

关键词： NOMA spectrum sensing feature detection satellite-terrestrial communication

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Antibodies in celiac disease:implications beyond diagnostics

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Cellular & Molecular Immunology 2011年第2期8卷 103-109页

作者： Sergio Caja Markku Maki Katri Kaukinen Katri Lindfors Pediatric research centre University of Tampere and Tampere University HospitalTampereFinland Medical School University of Tampere and Department of Gastroenterology and Alimentary Tract SurgeryTampere University HospitalTampereFinland

Celiac disease is a multisystemic dietary,gluten-induced autoimmune disorder characterized by the presence of transglutaminase(TG)2 serum *** autoantibodies targeting members of the TG family(TG2,TG3 and TG6)are found deposited in small-bowel mucosa and in extraintestinal tissues affected by the *** autoantibodies against other self-antigens also emerge in untreated celiac disease *** villous atrophy and crypt hyperplasia in small-bowel biopsy samples are still the gold standards in diagnostics,celiac disease-specific antibodies are widely used as diagnostic ***-induced small-bowel mucosal T-cell response is the cornerstone in the pathogenesis of the disorder,but humoral immunity may also play a central *** review article is focused on the autoantibodies that occur in the context of celiac *** article summarizes the diagnostic utility of different celiac-related antibodies and discusses their roles in the pathogenesis of the disease.

关键词： antibody celiacdisease diagnostics pathogenesis

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Effect of cooling rate and composition on microstructure and mechanical properties of ultrahigh-strength steels

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Journal of Iron and Steel research International 2019年第12期26卷 1350-1365页

作者： Mohammed Ali David Porter Jukka Komi Mamdouh Eissa Hoda El Faramawy Taha Mattar Materials and Mechanical Engineering Centre for Advanced Steels ResearchUniversity of OuluOulu 90014Finland Steel Technology Department Central Metallurgical Research and Development InstituteHelwanCairo 11421Egypt

The influence of cooling rate on the microstructure and mechanical properties of two new ultrahigh-strength steels(UHSSs)with different levels of C,Cr and Ni has been evaluated for the as-cooled and untempered *** UHSS had higher contents of C and Cr,while the other one had a higher Ni *** the basis of dilatation curves,microstructures,macrohardness and microhardness,continuous cooling transformation diagrams were constructed as a guide to heat treatment *** rates(CRs)of 60,1 and 0.01°C/s were selected for more detailed *** characterization was made by laser scanning confocal microscopy,field emission scanning electron microscopy combined with electron backscatter diffraction,electron probe microanalysis and X-ray *** properties were characterized using macrohardness,tensile and Charpy V-notch impact *** with the higher C and Cr contents showed lower transformation temperatures and slower bainite formation kinetics than that with the higher Ni *** cooling rates led to lower volume fractions and carbon contents of retained austenite together with finer prior austenite grain size,as well as effective final grain size and lath *** changes were accompanied by higher yield and tensile *** best combinations of strength and toughness were obtained with martensitic microstructures and by avoiding the formation of granular bainite accompanied by proeutectoid carbides at low *** the cooling rates studied,UHSS with the higher C and Cr contents showed the higher hardness and strength but at the cost of toughness.

关键词： Ultrahigh-strength steel Electroslag remelting Continuous cooling transformation diagram Microstructure feature Mechanical property

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Synchrotron radiation investigations of the Sr_2MgSi_2O_7:Eu^(2+),R^(3+) persistent luminescence materials

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Journal of Rare Earths 2009年第4期27卷 529-538页

作者： Tuomas Aitasalo Jukka Hassinen Jorma Hls Taneli Laamanen Mika Lastusaari Marja Malkamki Janne Niittykoski Pavel Novák Department of Chemistry University of Turku FI-20014 Turku Finland Turku University centre for Materials and Surfaces (MatSurf) Turku Finland Graduate School of Materials research (GSMR) Turku Finland Institute of Physics Academy of Sciences of the Czech Republic CZ-16253 Prague 6 Czech Republic

The electronic and defect energy level structure of polyerystalline Sr2MgSi2OT：Eu^2＋,R^3＋ persistent luminescence materials were studied with thermoluminescence and different synchrotron radiation spectroscopies （UV-VUV emission and excitation, X-ray absorption near-edge spectroscopy （XANES） and extended X-ray absorption f＇me structure （EXAFS））. Special attention was paid on the effect of the R3＋ co-dopants on the persistent luminescence properties of the materials. Theoretical calculations using the density functional theory （DFT） were carried out simultaneously with the experimental work. The experimental band gap energy （Eg） value of ca. 7.1 eV agreed very well with the DFT value of 6.7 eV. The variation of the Eg value was attempted to relate with the trap structure as well as with the different properties of the R3＋ co-dopants. The trap level energy distribution depended strongly on the R3＋ co-dopant except for the shallowest trap energy above the room temperature remaining practically the same, however. The different processes in the mechanism of persistent luminescence from Sr2MgSi2OT：Eu^2＋,R^3＋ were assembled and their contributions discussed.

关键词： strontium magnesium disilicate europium persistent luminescence synchrotron radiation thermoluminescence mechanism rare earths

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Bridging mapping and simulation modelling in the ecosystem service assessments of boreal forests:effects of bioenergy production on carbon dynamics

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Forest Ecosystems 2021年第1期8卷 35-49页

作者： Anu Akujärvi Anna Repo Altti M.Akujärvi Jari Liski Finnish Environment Institute SYKE Biodiversity CentreLatokartanonkaari 11FI-00790 HelsinkiFinland University of Helsinki Department of Geosciences and GeographyP.O.Box 64FI-00014 HelsinkiFinland Natural Resources Institute finland(Luke) P.O.Box 2FI-00791 HelsinkiFinland VTT Technical research centre of finland LTD P.O.Box 1000FI-02044 VTT EspooFinland Finnish Meteorological Institute Climate System Research UnitP.O.Box 503FI-00101 HelsinkiFinland

Background:Increasing the use of forest harvest residues for bioenergy production reduces greenhouse emissions from the use of fossil ***,it may also reduce carbon stocks and habitats for deadwood dependent ***,simple tools for assessing the trade-offs of alternative management practices on forest dynamics and their services to people are *** objectives of this study were to combine mapping and simulation modelling to investigate the effects of forest management on ecosystem services related to carbon cycle in the case of bioenergy production;and to evaluate the suitability of this approach for assessing ecosystem services at the landscape *** level simulations of forest growth and carbon budget were combined with extensive multi-source forest inventory data across a southern boreal landscape in *** changes in the stand age class distribution over the study region were simulated to mimic variation in management ***:The mapping framework produced reasonable estimates of the effects of forest management on a set of key ecosystem service indicators:the annual carbon stocks and fluxes of forest biomass and soil,timber and energy-wood production and the coarse woody litter production over a simulation period 2012–*** harvesting,affecting the stand age class distribution,was a key driver of the carbon stock changes at a landscape *** forest harvest residues in the final felling caused carbon loss from litter and soil,particularly with combined aboveground residue and stump *** also reduced the annual coarse woody litter production,demonstrating negative impacts on deadwood abundance and,consequently,forest ***:The refined mapping framework was suitable for assessing ecosystem services at the landscape *** procedure contributes to bridging the gap between ecosystem service mapping and detailed simulation modelling in boreal *** allows for v

关键词： Carbon budget Ecosystem services Forest management Forest bioenergy Landscape level Mapping Modelling

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A new technique for fault diagnosis in transformer insulating oil based on infrared spectroscopy measurements

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High Voltage 2024年第2期9卷 319-335页

作者： Mohamed M.F.Darwish Mohamed H.A.Hassan Nagat M.K.Abdel-Gawad Matti Lehtonen Diaa-Eldin A.Mansour Department of Electrical Engineering Faculty of Engineering at ShoubraBenha UniversityCairoEgypt Department of Electrical Engineering and Automation School of Electrical EngineeringAalto UniversityEspooFinland Department of Electrical Power Engineering Egypt-Japan University of Science and Technology(E-JUST)New Borg El-Arab CityEgypt Department of Electrical Power and Machines Engineering Faculty of EngineeringTanta UniversityTantaEgypt

Condition monitoring of the insulating system within power transformers has a massive importance according to the electrical *** gas analysis(DGA)is frequently used for this ***,DGA lacks the necessary level of accuracy to identify all equipment faults,particularly in their initial stages of ***,it does not have the capability for real-time monitoring and relies on manual sampling and laboratory testing,causing potential delays in fault ***,the interpretation of DGA data necessitates specialised expertise,which may pose difficulties for smaller entities that have limited access to ***,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 *** inception faults that were considered in this study were the electrical fault(discharges of high energy)and the thermal fault(300°C

关键词： fault diagnosis spectroscopy

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