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| 1 | Age structure in neutral theory resolves inconsistencies related to reproductive-size threshold显示文摘Aims Neutral theory consists of a suite of models that assume ecological equivalence among individual organisms.They have been most commonly applied to tropical forest tree communities either as null models or as approximations.Neutral models typically only include reproductive adults;therefore,fitting to empirical tree community data requires defining a reproductive-size threshold,which for trees is usually set arbitrarily to a diameter at breast height(DBH)of 100 mm.The inevitable exclusion of some reproductive adults and inclusion of some saplings cause a non-random sampling bias in neutral model fits.Here,we investigate this problem and resolve it by introducing simple age structure into a neutral model.Methods We compared the performance and sensitivity of DBH threshold of three variants of a spatially explicit neutral model:the traditional model,a model incorporating random sampling and a model with two distinct age classes—reproductive adults and saplings.In the age-structured model,saplings are offspring from adults that disperse according to a Gaussian dispersal kernel around the adults.The only extra parameter is the ratio of adults to saplings,which is not a free parameter but directly measurable.We used species–area relationships(SARs)to explore the predicted effect of saplings on the species richness at different scales in our model.We then evaluated the three model variations to find the parameters required to maintain the observed level of species richness in the 50-ha plot on Barro Colorado Island(BCI).We repeated our analysis filtering the data at different minimum tree-size thresholds in order to find the effect this threshold has on our results.Lastly,we used empirical species–individual relationships(SIRs)to test the pre-existing hypothesis that environmental filtering is the primary cause of differences between the assemblage of saplings and that of adults on BCI.Important Findings Our age-structured neutral model was characterized by SARs that were insensitive to the presence of saplings at large scales and highly sensitive to them at small scales.Both models without age structure were highly sensitive to the DBH threshold chosen in a way that could not be explained based on random samplings alone.The age-structured neutral model,which allowed for non-random sampling based on life stage,was consistent with species richness observations.Our analysis of empirical SIRs did not support environmental filtering as a dominant force,but it did show evidence for other differences between age classes.Age can now be easily incorporated into future studies of neutral models whenever there is a concern that a sample is not entirely composed of reproductive adult individuals.More generally,we suggest that modeling studies using tree data subject to a minimum size threshold should consider the sensitivity of their results to that threshold. | James Rosindell Patrick A.Jansen Rampal S.Etienne | 2012 | Journal of Plant Ecology2012，5，1： | 1 |
| 2 | The molecular conformation of silk fibroin regulates osteogenic cell behavior by modulating the stability of the adsorbed protein-material interface显示文摘Silk fibroin(SF)can be used to construct various stiff material interfaces to support bone formation.An essential preparatory step is to partially transform SF molecules from random coils toβ-sheets to render the material water insoluble.However,the influence of the SF conformation on osteogenic cell behavior at the material interface remains unknown.Herein,three stiff SF substrates were prepared by varying theβ-sheet content(high,medium,and low).The substrates had a comparable chemical composition,surface topography,and wettability.When adsorbed fibronectin was used as a model cellular adhesive protein,the stability of the adsorbed protein-material interface,in terms of the surface stability of the SF substrates and the accompanying fibronectin detachment resistance,increased with the increasingβ-sheet content of the SF substrates.Furthermore,(i)larger areas of cytoskeleton-associated focal adhesions,(ii)higher orders of cytoskeletal organization and(iii)more elongated cell spreading were observed for bone marrow-derived mesenchymal stromal cells(BMSCs)cultured on SF substrates with high vs.lowβ-sheet contents,along with enhanced nuclear translocation and activation of YAP/TAZ and RUNX2.Consequently,osteogenic differentiation of BMSCs was stimulated on highβ-sheet substrates.These results indicated that theβ-sheet content influences osteogenic differentiation of BMSCs on SF materials in vitro by modulating the stability of the adsorbed protein-material interface,which proceeds via protein-focal adhesion-cytoskeleton links and subsequent intracellular mechanotransduction.Our findings emphasize the role of the stability of the adsorbed protein-material interface in cellular mechanotransduction and the perception of stiff SF substrates with differentβ-sheet contents,which should not be overlooked when engineering stiff biomaterials. | Yanlin Long Xian Cheng John A.Jansen Sander G.C.Leeuwenburgh Jing Mao Fang Yang Lili Chen | 2021 | Bone Research2021，9，2： | 1 |
| 3 | Anomalous failure of configuration interaction—Singles (CIS) method in the computation of the electronic states of N,N′‐bis(4′‐aminophenyl)‐1,4‐quinonenediimine显示文摘 | Lawrence T.Sein YenWei ThanhDuong Mark D.Kemmerer Susan A.Jansen | 1999 | Int. J. Quantum Chem. . 1999 (4‐5)1999，，4： | 1 |
| 4 | In situ formation of porous space maintainers in a composite tissue defect显示文摘 | Patrick P.Spicer James D.Kretlow Allan M.Henslee MengShi SimonYoung NagiDemian John A.Jansen Mark E.Wong Antonios G.Mikos F. KurtisKasper | 2012 | J Biomed Mater Res2012，，4： | 1 |
| 5 | Electrophoretic deposition of silk fibroin coatings with pre-defined architecture to facilitate precise control over drug delivery显示文摘The therapeutic precision and clinical applicability of drug-eluting coatings can be substantially improved by facilitating tunable drug delivery.However,the design of coatings which allows for precise control over drug release kinetics is still a major challenge.Here,a double-layered silk fibroin(SF)coating system was constructed by sequential electrophoretic deposition.A mixture of dissolved Bombyx mori SF(bmSF)molecules and pre-made bmSF nanospheres at different ratios was deposited as under-layer.Subsequently,this underlayer was covered by a top-layer comprising Antheraea pernyi SF(apSF)molecules(rich in arginylglycylaspartic acid,RGD)to improve the cellular response of the resulting double-layered coatings.Additionally,model drug doxycycline was either pre-mixed with dissolved bmSF molecules or pre-loaded into pre-made bmSF nanospheres at the same amount before their mixing and deposition.The thickness and nanosphere content of the under-layer architecture were proportional to the deposition time and nanosphere concentration in precursor mixtures,respectively.The surface topography,wettability,degradation rate and adhesion strength were comparable within the double-layered coating system.As expected,RGD-rich apSF top-layer improved cell adhesion,spreading and proliferation compared with bmSF top-layer.Furthermore,the amount and duration of drug release increased linearly with increasing nanosphere concentration at fixed deposition time,whereas drug release amount increased linearly with increasing deposition time.These results indicate that the dosage and kinetics of loaded drugs can be quantitatively tailored by altering nanosphere concentration and deposition time as main processing parameters.Overall,this study illustrates the strong potential of pre-defining coating architecture to facilitate control over drug delivery. | Xian Cheng Dingpei Long Lili Chen John A.Jansen Sander C.G.Leeuwenburgh Fang Yang | 2021 | Bioactive Materials2021，6，11： | 1 |
| 6 | Interaction strengths in food webs: issues and opportunities显示文摘 | Eric L.Berlow Anje‐MargietNeutel Joel E.Cohen Peter C.De Ruiter BoEbenman MarkEmmerson Jeremy W.Fox Vincent A. A.Jansen J.Iwan Jones Giorgos D.Kokkoris Dmitrii O.Logofet Alan J.McKane Jose M.Montoya OwenPetchey | 2004 | Journal of Animal Ecology2004，，3： | 1 |
| 7 | 基于策略管理的黄金时代显示文摘几十年来,电信设备、网络和服务的运营是建立在管理信息基础(MIB)、命令行接口(CLI)以及诸如简单网络管理协议(SNMP)、公共管理信息协议(CMIP)和(TL1)之类的管理协议之上的。虽然这些技术对于配置和运营现有网络和服务是有用的,但很明显,它们的复杂性、一致性和效率已不再能满足运营商降低运营支出(Opex)的要求。只有当业务可以在网络管理(NMS)和运营支撑系统(OSS)层面上更容易地进行配置、操作和集成时,才能降低管理开支。要实现上述目标,需要改进管理软件和网元中的新功能。 | F.Cuervo A.Jansen | 2004 | 网络电信2004，6，6： | 0 |
| 8 | 在网络管理中采用以互联网为中心的技求显示文摘运营支撑系统(OSS),特别是网络和业务管理系统,在历史上是作为专用软件应用而创建的。基于开放系统互连(OSI)模型,已针对此应用域开发出了一些专有的协议栈和工具集。最明显的是,这包括国际电联一电信(ITU-T)Q3栈,它使用基于抽象语法标记(ASN.1)所规定数据结构的公共管理信息业务,以便于管理信息在电信管理网络(TMN)中的交换。互联网工程任务组(IETF)基于简单网络管理协议(SNMP)和系统管理信息(SMI)已经开发了更轻量级的版本,来展示数据应用日管理信息。 | A.Jansen A.Elkady P.Fogliata | 2004 | 网络电信2004，6，6： | 0 |
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