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Importance of periphytic biofilms for carbon cycling in paddy fields:A review

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Pedosphere 2024年第1期34卷 36-43页

作者： Lei ZHOU Yonghong WU Junzhuo LIU Pengfei SUN Ying XU jan DOLFING Robert GMSPENCER erik JEPPESEN State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Zigui Three Gorges Reservoir Ecosystem Observation and Research Station of Ministry of Water Resources of the People's Republic of ChinaYichang 443605China College of Nanjing University of Chinese Academy of SciencesNanjing 211135China Faculty of Energy and Environment Northumbria UniversityNewcastle upon Tyne NE18QHUK Department of Earth Ocean and Atmospheric ScienceFlorida State UniversityTallahassee FL 32306USA Department of Ecoscience&Centre for Water Technology(WATEC) Aarhus UniversityAarhus DK-8000Denmark Sino-Danish Centre for Education and Research Beijing 100049China Limnology Laboratory Department of Biological Sciences and Centre for Ecosystem Research and Implementation(EKOSAM)Middle East Technical UniversityAnkara 06800Turkiye Institute of Marine Sciences Middle East Technical UniversityMersin 33731Turkiye

Paddy fields play an important role in global carbon(C) cycling and are an important source of methane(CH_(4)) emissions. Insights into the processes influencing the dynamics of soil organic C(SOC) in paddy fields are essential for maintaining global soil C stocks and mitigating climate change. Periphytic biofilms composed of microalgae, bacteria, and other microorganisms are ubiquitous in paddy fields, where they directly mediate the transfer of elements at the soil-water interface. However, their contributions to C turnover and exchange have been largely neglected. Periphytic biofilms affect and participate in soil C dynamics by altering both abiotic(e.g., pH and redox potential) and biotic conditions(e.g., microbial community composition and metabolism). This review summarizes the contributions of periphytic biofilms to soil C cycling processes, including carbon dioxide fixation, SOC mineralization, and CH_(4) emissions. Future research should be focused on: i) the mechanisms underlying periphytic biofilm-induced C fixation and turnover and ii) quantifying the contributions of periphytic biofilms to soil C uptake, stabilization, and sequestration in paddy fields.

关键词： carbon fixation carbon mineralization carbon sequestration methane emission microbial aggregates soil organic carbon

Realism, Normativity and Professor Mearsheimer

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Philosophy Study 2024年第2期14卷 63-65页

作者： jan-erik Lane Geneva University GenevaSwitzerland

International relations or politics are a dynamic discipline within politics. It concentrates upon the understanding or explanation of conflict and power between nations or countries. It is of course highly relevant today with much warfare or threats thereof. One central theory is the so-called realism or neorealism. Its foremost representative today is Professor Mearsheimer. Professor John Mearsheimer has put several of his well-known lectures on YouTube. In these he spells out how he looks upon international politics today through a neorealist approach. Very much worth listening to, we must though question consistency in his message.

关键词： War conflict between nations neorealism

Fiber effects in nutrition and gut health in pigs

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Journal of Animal Science and Biotechnology 2014年第3期5卷 273-279页

作者： jan erik Lindberg Department of Animal Nutrition and Management Swedish University of Agricultural Sciences

Dietary fiber is associated with impaired nutrient utilization and reduced net energy values. However, fiber has to be included in the diet to maintain normal physiological functions in the digestive tract. Moreover, the negative impact of dietary fiber will be determined by the fiber properties and may differ considerably between fiber sources. Various techniques can be applied to enhance nutritional value and utilization of available feed resources. In addition, the extent of fiber utilization is affected by the age of the pig and the pig breed. The use of potential prebiotic effects of dietary fiber is an attractive way to stimulate gut health and thereby minimize the use of anti-microbial growth promoters. Inclusion of soluble non-starch polysaccharides （NSP） in the diet can stimulate the growth of commensal gut microbes, inclusion of NSP from chicory results in changes in gut micro-environment and gut morphology of pigs, while growth performance remains unaffected and digestibility was only marginally reduced. The fermentation products and pH in digesta responded to diet type and were correlated with shifts in the microbiota. Interestingly, fiber intake will have an impact on the expression of intestinal epithelial heat-shock proteins in the pig. Heat-shock proteins have an important physiological role in the gut and carry out crucial housekeeping functions in order to maintain the mucosal barrier integrity. Thus, there are increasing evidence showing that fiber can have prebiotic effects in pigs due to interactions with the gut micro-environment and the gut associated immune system.

关键词： Breed Gut health Fiber Pigs Prebiotics Utilization

Controlling Membrane Phase Separation of Polymersomes for Programmed Drug Release

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Chinese Journal of Polymer Science 2022年第9期40卷 1006-1015页

作者： Shuai Chen erik jan Cornel Jian-Zhong Du Department of Orthopedics Shanghai Tenth People’s HospitalSchool of MedicineTongji UniversityShanghai 200072China Department of Polymeric Materials School of Materials Science and EngineeringTongji UniversityShanghai 201804China

Programmed release of small molecular drugs from polymersomes is of great importance in drug delivery.A significant challenge is to adjust the membrane permeability in a well-controlled ***,we propose a strategy for controlling membrane phase separation by photo-cross-linking of the membrane-forming blocks with different molecular *** synthesized three amphiphilic block copolymers with different membrane-forming blocks,which are poly(ethylene oxide)_(43)-b-poly((ε-caprolactone)_(45)-stat-((α-(cinnamoyloxymethyl)-1,2,3-triazol)caprolactone)_(25))(PEO_(43)-b-P(CL_(45)-stat-CTCL_(25))),PEO_(43)-b-P(CL_(108)-stat-CTCL_(16)),and PEO_(43)-b-PCTCL_(4)-b-PCL_(79).These polymers were self-assembled into polymersomes using either a solvent-switch or powder rehydration method,and the obtained polymersomes were characterized by dynamic light scattering and transmission electron *** the phase separation patterns within the polymersome membranes were investigated by mesoscopic dynamics(MesoDyn)*** further confirm the change of the membrane permeability that resulted from the phase separation within the membrane,doxorubicin,as a small molecular drug,was loaded and released from the *** to the incompatibility between membrane-forming moieties(PCTCL and PCL),phase separation occurs and the release rate can be tuned by controlling the membrane phase pattern or by ***,besides the compacting effect by formation of chemical bonds in the membrane,the cross-linking process can act as a driving force to facilitate the rearrangement and re-orientation of the phase pattern,which also influences the drug release behavior by modulating the cross-membrane distribution of the amorphous PCTCL *** this way,the strategy of focusing on the membrane phase separation for the preparation of the polymersomes with finely tunable drug release rate can be envisioned and designed accordingly,which is of great signifi

关键词： Polymersome Drug delivery Phase separation Programmed drug release

Gallbladder bile composition in patients with Crohn's disease

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World Journal of Gastroenterology 2006年第1期12卷 70-74页

作者： Annika Lapidus jan-erikkerlund Curt Einarsson Centre of Gastrointestinal Disease Ersta HospitalDepartment of SurgeryDanderyd Hospital and Department of Gastroenterology and HepatologyKarolinska Institutet at Karolinska University Hospital HuddingeStockholmSweden

AIM： To further elucidate the pathogenesis and mechanisms of the high risk of gallstone formation in Crohn＇s disease. METHODS： Gallbladder bile was obtained from patients with Crohn＇s disease who were admitted for elective surgery （27 with ileal/ileocolonic disease and 7 with Crohn＇s colitis）. Fourteen gallstone patients served as controls. Duodenal bile was obtained from ten healthy subjects before and after the treatment with ursodeoxycholic acid. Bile was analyzed for biliary lipids, bile acids, bilirubin, crystals, and crystal detection time （CDT）. Cholesterol saturation index was calculated. RESULTS： The biliary concentration of bilirubin was about 50% higher in patients with Crohn＇s disease than in patients with cholesterol gallstones. Ten of the patients with Crohn＇s disease involving ileum and three of those with Crohn＇s colitis had cholesterol saturated bile. Four patients with ileal disease and one of those with colonic disease displayed cholesterol crystals in their bile. About 1/3 of the patients with Crohn＇s disease had a short CDT. Treatment of healthy subjects with ursodeoxycholic acid did not increase the concentration of bilirubin in duodenal bile. Several patients with Crohn＇s disease, with or without ileal resection/disease had gallbladder bile supersaturated with cholesterol and short CDT and contained cholesterol crystals. The biliary concentration of bilirubin was also increased in patients with Crohn＇s colitis probably not due to bile acid malabsorption. CONCLUSION： Several factors may be of importance for the high risk of developing gallstones of both cholesterol and pigment types in patients with Crohn＇s *** skillful technical assistance of Ms Lisbet Benthin and Ms Ingela Arvidsson is acknowledged.

关键词： Bile acid Biliary lipid composition Bilirubin Crohn's disease Gallstone disease

Fecal microbiome of growing pigs fed a cereal based diet including chicory(Cichorium intybus L.) or ribwort(Plantago lanceolata L.) forage

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Journal of Animal Science and Biotechnology 2016年第2期7卷 167-175页

作者： Johan Dicksved janet K.jansson jan erik Lindberg Department of Animal Nutrition and Management Swedish University of Agricultural Sciences Department of Microbiology Swedish University of Agricultural Sciences Division of Biology Earth and Biological Sciences Pacific Northwest National Laboratories

Background： The purpose of this study was to investigate how inclusion of chicory forage or ribwort forage in a cereal-based diet influenced the fecal microbial community（microbiome） in newly weaned（35 days of age） *** piglets were fed a cereal-based diet without（B） and with inclusion（80 and 160 g/kg air-dry forage） of vegetative shoots of chicory（C） and leaves of ribwort（R） forage in a 35-day growth trial. Fecal samples were collected at the start（D0）, 17（D17） and 35（D35） days after weaning and profiles of the microbial consortia were generated using terminal restriction fragment length polymorphism（T-RFLP）. 454-FLX pyrosequencing of 16 S r RNA gene amplicons was used to analyze the microbial composition in a subset of the samples already analyzed with ***： The microbial clustering pattern was primarily dependent on age of the pigs, but diet effects could also be observed. Lactobacilli and enterobacteria were more abundant at D0, whereas the genera Streptococcus, Treponema,Clostridium, Clostridiaceae1 and Coprococcus were present in higher abundances at D35. Pigs fed ribwort had an increased abundance of sequences classified as Treponema and a reduction in lactobacilli. However, the abundance of Prevotellaceae increased with age in on both the chicory and the ribwort diet. Moreover, there were significant correlations between the abundance of Bacteroides and the digested amount of galactose, uronic acids and total non-starch polysaccharides, and between the abundance of Bacteroidales and the digested amount of ***： This study demonstrated that both chicory and ribwort inclusion in the diet of newly weaned pigs influenced the composition of the fecal microbiota and that digestion of specific dietary components was correlated with species composition of the microbiota. Moreover, this study showed that the gut will be exposed to a dramatic shift in the microbial community structure several weeks after weaning.

关键词： Amplicon sequencing Chicory Microbiome Ribwort Uronic acid Weaning 16S

Hydrological Responses and Flow Pathways in an Acrisol on a Forested Hillslope with a Monsoonal Subtropical Climate

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Pedosphere 2017年第6期27卷 1037-1048页

作者： Lars-erik SORBOTTEN jannes STOLTE WANG Yanhui jan MULDER Norconsult AS N-1338 Sandvika(Norway) Norwegian Institute of Bioeconomy Research(NIBIO) N-1430 Aas(Norway) Research Institute of Forest Ecology Environment and ProtectionChinese Academy of ForestryBeijing 100091(China) Department of Environmental Sciences Norwegian University of Life SciencesN-1432 Aas(Norway)

The nature of subsurface flow depends largely on hydraulic conductivity of the vadoze zone, permeability of the underlying bedrock, existence of soil layers differing in hydraulic properties and macropore content, soil depth, and slope *** of flow pathways on forested hillslopes is essential to understand hydrological dynamics and solute transport ***, with their argic Bt horizons, are challenging in this *** further elucidate flow pathways of water and short-term variability of soil moisture patterns in Acrisols, a field study was conducted on a forested hillslope in a sub-catchment of the Tie Shan Ping(TSP)watershed, 25 km northeast of Chongqing City, *** catchment is covered by a mixed secondary forest dominated by Masson pine(Pinus massoniana).Soil saturated hydraulic conductivity(K sat) was significantly reduced at the interface between the AB and Bt horizons(2.6 × 10^(-5) vs.1.2 × 10^(-6) m s^(-1)), which led to that the flow volume generated in the Bt horizon was of little quantitative importance compared to that in the AB *** was a marked decrease in porosity between the OA and AB horizons, with a further decrease deeper in the mineral ***, the content of soil pores > 300 μm was higher in the AB horizon(14.3%)than in the Bt horizon(6.5%).This explained the difference in soil K sat *** study showed that Bt horizon had limited water transport capability, forcing part of the infiltrated rainwater as interflow through the OA and AB ***, the topsoil responded quickly to rainfall events, causing frequent cycles of saturation and aeration of soil pores.

关键词： dye tracer hillslope hydrology hydraulic conductivity preferential flow soil pores subsurface lateral flow

A Discontinuous Galerkin Extension of the Vertex-Centered Edge-Based Finite Volume Method

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Communications in Computational Physics 2009年第2期5卷 456-468页

作者： Martin Berggren Sven-erik Ekstrom jan Nordstrom Department of Computing Science Ume˚a UniversitySE-90187 Ume˚a Sweden Division of Scientific Computing Department of Information TechnologyUppsala UniversityBox 337SE-75105 UppsalaSweden

The finite volume(FV)method is the dominating discretization technique for computational fluid dynamics(CFD),particularly in the case of compressible *** discontinuous Galerkin(DG)method has emerged as a promising highaccuracy *** standard DG method reduces to a cell-centered FV method at lowest ***,many of today’s CFD codes use a vertex-centered FV method in which the data structures are edge *** develop a new DG method that reduces to the vertex-centered FV method at lowest order,and examine here the new scheme for scalar hyperbolic ***,the method shows optimal-order accuracy for a smooth linear *** applying a basic hp-adaption strategy,the method successfully handles *** also discuss how to extend the FV edge-based data structure to support the new *** this way,it will in principle be possible to extend an existing code employing the vertex-centered and edge-based FV discretization to encompass higher accuracy through the new DG method.

关键词： Discontinuous Galerkin methods finite volume methods dual mesh vertex-centered edge-based CFD

Oxidative stress physiology in relation to life history traits of a free-living vertebrate:the spotted snow skink,Niveoscincus ocellatus

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Integrative Zoology 2011年第2期6卷 140-149页

作者： Caroline ISAKSSON Geoffrey M.WHILE Mats OLSSON jan KOMDEUR erik WAPSTRA University of Groningen Animal Ecology GroupHarenThe Netherlands University of Wollongong School of Biological SciencesWollongongNew South Wales University of Tasmania School of ZoologyHobartTasmaniaAustralia

Recent research suggests that oxidative stress,via its links to metabolism and senescence,is a key mechanism linking life history traits such as fecundity and growth with survival;however,this has rarely been put under empirical scrutiny within free-living *** a wild population of live-bearing skinks,we explored how plasma antioxidant activity(OXY),reactive oxidative metabolites(ROM),and the estimated oxidative stress index are associated with female and male life *** found that male skinks have a significantly higher ROM and estimated oxidative stress index than female skinks,but this was not accompanied by a sex difference in *** sexes showed a non-linear association between OXY and age,indicating that the oldest and youngest individuals had the lowest ***,female skinks with high OXY showed a decreased probability of survival to the following ***,we found no significant associations between female reproductive investment(litter size or litter mass)or parturition date(***)and oxidative ***,our results offer mixed support for a role of oxidative stress in mediating life history traits and suggest that future studies need to explore oxidative stress during vitellogenesis in addition to using an intra-individual approach to understand the cost of reproduction and patterns of aging.

关键词： antioxidants life history Niveoscincus ocellatus oxidative stress reptile