摘要：植物的生态过程依赖于叶片和根系的功能运行,但少有研究同时关注这两类性状在群落中的分布格局(CTD)。本文测定了广东亚热带森林44种共生木本植物的16个叶片和根系性状,旨在检验类比的叶片和根系性状是否耦合,是否沿类似的功能性状谱变异,是否表现出类似的CTD,其CTD和群落加权平均性状值(CWM)是否沿环境梯度表现出类似的响应。研究结果表明,叶片和根系性状变异的第一轴均呈显出由资源获取向资源保守变异的经济学谱,但叶片变异的第二轴主要由叶片碳含量表征,而根系变异的第二轴主要由反映菌根协作程度的根系粗细表征。类比的叶片和根系化学性状整体正相关,但形态性状的耦合程度较低。在群落水平上,叶片和根系性状第一轴的CWM均随海拔升高而变得更保守,而第二轴的变化则不一致。随土壤磷含量的降低或钾含量的升高,根系变得更细和在养分性状上更保守,而叶片性状无显著变化。当整合多维性状轴时,叶片性状呈发散格局,且随海拔、土壤磷和钾含量的增加呈收敛趋势;而根系性状呈收敛格局,但沿上述环境梯度呈发散趋势。该研究强调,叶片和根系性状与环境互作的差异可能导致不同的性状分布格局;植物可通过多样的地上和地下功能设计应对环境异质性。

摘要：DNA-based approaches to systematics have changed dramatically during the last two decades with the rise of DNA barcoding methods and newer multi-locus methods for species delimitation. During the last half-decade, partly driven by the new sequencing technologies, the focus has shifted to multi-locus sequence data and the identification of species within the frame-work of the multi-species coalescent （MSC）. In this paper, I discuss model-based Bayesian methods for species delimitation that have been developed in recent years using the MSC. Several approximate methods for species delimitation （and their limitations） are also discussed. Explicit species delimitation models have the advantage of clarifying more precisely what is being delimited and what assumptions we are making in doing so. Moreover, the methods can be very powerful when applied to large multi-locus datasets and thus take full advantage of data generated using today＇s technologies [Current Zoology 61 （5）： 846-853,2015].

摘要：The zebra mussel is an important aquatic pest that causes great damage to freshwater-dependent industries, due to biofouling. The main goal of the project discussed here is to develop improved solutions to control this species. Three approaches have been explored in an attempt to design innovative application strategies for existing biocides： （i） encapsulation of toxins; （ii） combination of toxins; （iii） investigation of the seasonal variation of the species＇ tolerance to toxins. In this paper, the principles behind these approaches and the major results on each topic are presented. The benefits of adopting a chemical product engineering approach in conducting this project are also discussed.

摘要：Biodiversity assessment for tree species was conducted in three forest fragments ofthe Taita Hills, southeastern Kenya to compare species diversity between and within three exotic forest plantations of pine, eucalyptus, cypress and the indigenous forests. The study sites were： Ngangao （120 ha）, Chawia （86 ha）, and Mbololo （185 ha）. A Y-plot design was used to sample 32 plots comprising of 65 subplots. At each subplot, all juvenile trees of 5 cm and above in diameter at breast height （DBH） were enumerated and recorded by species. Tree regeneration （seedlings and saplings） was tallied by species. The Shannon-Weiner Index was used to calculate species diversity and evenness. The derived Shannon’s indices were further converted into effective numbers to show the magnitude of differences in species biodiversities. To evaluate dif-ferences in species diversities, a one way ANOVA was conducted and to separate the means, Tukey＇s HSD and Duncan’s tests were used for even and uneven number of samples respectively. Jaccard’s similarity index was used to assess species similarities. There were more than 58 species whose stem densities varied between 10 and 2 000 trees per *** were significant differences in species diversities between forest types and sites; the indigenous forests showed higher diversities than the exotic forests. Similarly, Chawia sites had higher species diversity than both Ngangao and Mbololo. Chawia also had a higher number of regen-erated species than the two other sites, including species such as Xymalos monospora, Rapanea melanophloeos, and Syzygium guineense, which are associated with low levels of disturbance. These findings indicate that the indigenous forest is more diverse in species as would be expected in the tropics. The high species diversity in Chawia could be accounted for by the higher levels of disturbance it underwent, unlike the two other sites. The regeneration of species associated with low levels of disturbance found in the ex

摘要：Knowledge about the spatial and temporal scales of both habitat use and the functional significance of different adaptations is essential for an understanding of the population dynamics of invertebrate assemblages. This fundamental knowledge is not only interesting from an academic point of view, but is sorely lacking and needed in the field of restoration ecology. Many species are threatened due to degradation. Knowing what environmental conditions are needed dtLring the life cycle of these species is important in the design of restoration measures which aim to lift existing bottlenecks for threatened species. To assess the relative importance of water type and microhabitat in structuring the invertebrate assemblage during different seasons, invertebrates were sampled in three water bodies differing in trophic level and acidity. Different parts within a water body （microhabitats） were sampled separately and each water body was sampled in all four seasons. Results show that water body is an important factor structuring the invertebrate assemblage early in the season, whereas microhabitat became more important later in the season. Structural complexity of microhabitats was related to the type of locomotion employed by invertebrates. Seasonal differences could be related to population dynamics （reproduction, mortality）. Moreover, fluctuations in resource availability were expected to differ between the water bodies, with highest fluctuations in the eutrophic water body and with fluctuations becoming less predictable later in the season. This was confirmed by the data： species synchronization to pulses in food availability was strongest in the eutrophic water body. Moreover, synchronization was strongest in summer, while in autumn waters were invaded by dispersive species. Based on these results a synthesis is presented on the functioning of the different waters during the different seasons.

摘要：Photocatalysis is believed to be one of the best methods to realize sustainable H2 production. However, achieving this through heterogeneous photocatalysis still remains a great challenge owing to the absence of active sites, sluggish surface reaction kinetics, insufficient charge separation, and a high thermodynamic barrier. Therefore, cocatalysts are necessary and of great significance in boosting photocatalytic H2 generation. This review will focus on the promising and appealing low-cost Ni-based H2-generation cocatalysts as the alternatives for the high-cost and low-abundance noble metal cocatalysts. Special emphasis has been placed on the design principle, modification strategies for further enhancing the activity and stability of Ni-based cocatalysts, and identification of the exact active sites and surface reaction mechanisms. Particularly, four types of modification strategies based on increased light harvesting, enhanced charge separation, strengthened interface interaction, and improved electrocatalytic activity have been thoroughly discussed and compared in detail. This review may open a new avenue for designing highly active and durable Ni-based cocatalysts for photocatalytic H2 generation.

摘要：Plants growing in nutrient-rich environment are predicted to be less defended than conspecifics under nutrient ***,less is known about the effects of nutrient levels on tolerance and induced resistance,and whether the effects differ between native and introduced populations of invasive *** performed a greenhouse experiment with introduced(the USA)and native(Argentina)genotypes of Alternanthera philoxeroides in order to study the effects of soil nitrogen levels on plant growth,constitutive and herbivore(Agasicles hygrophila)-induced chemical defense,and herbivory *** measured total biomass,elongation rate(as proxy of growth rate),carbon and nitrogen,and the concentration of triterpenoid saponins(defensive chemicals)in leaves and *** resistance(+33%higher leaf triterpenoid saponins in control treatment at low nitrogen level)and tolerance[less decreased total biomass after herbivory treatment(−24%and−15%for high and low nitrogen levels)]were favored at lower nitrogen level,while induced resistance was favored at higher nitrogen level(+24%increased leaf triterpenoid saponins after herbivory treatment at high nitrogen level).Constitutive resistance and tolerance exhibited trade-offs with growth rate,while induced resistance positively correlated with growth ***,the introduced genotypes had−6%lower content of leaf carbon in the presence of herbivores than the native genotypes at low nitrogen level,but such difference was absent at high nitrogen *** results indicate that soil nitrogen levels influence the preference of different defensive strategies of plant,and interweave with herbivory to determine the performance of introduced genotypes.

摘要：Hydrogel-Ⅰ was fabricated via sodium alginate in situ-embedding with MAL powders and then applied to decontaminating Pb(Ⅱ) from water. Conditions for preparing Hydrogel-Ⅰ and the adsorption of Pb(Ⅱ) over Hydrogel-I were optimized through response surface methodology coupled with central composite design. XPS revealed that the groups of —OH, —COO—, —NH, —NHand —CSS— carried by Hydrogel-Ⅰ were responsible for the uptake of Pb(Ⅱ). Ions exchange, surface complexation, electrostatic attraction and pore-filling effect contributed to the adsorption process. Adsorption performances of Pb(Ⅱ) by Hydrogel-Ⅰ and MAL powders were compared. Although they exhibited similar adsorption rate and maximum adsorption capacity(qm), the reusing ability of Hydrogel-Ⅰ was better and it was easier to be separated from aqueous solution after treatment. Even compared with organic hydrogel materials,Hydrogel-Ⅰ presented relatively quick adsorption speed and high adsorption capacity. It can be concluded that Hydrogel-Ⅰ could be an alternative scavenger for the treatment of Pb(Ⅱ) from aqueous solution.

摘要：Currently,cell culture models play a key role in determining cell behavior under various ***,the accurate simulation of cellular behavior that imitates the body’s conditions remains a ***,to overcome this obstacle,three-dimensional cell culture models have been *** tissues/organs-on-chips(TOOCs)are new devices that have provided the opportunity to culture cells in a medium that is almost similar to the physiological conditions of the *** can be designed in simple or complex models,which are mostly fabricated by soft *** novel structures have been developed to mimic the conditions of various tissues and organs;however,microfluidic models for oral and dental tissues have not yet been widely *** application of TOOCs for oral tissues/organs can provide the opportunity to study cell interactions with biomaterials used in ***,TOOCs can provide the opportunity to study the cellular interactions and developmental stages of oral tissues/organs more *** review of the current advances in the field of TOOC development for oral tissues provides a comprehensive understanding of this burgeoning concept,shows the progress and applications of these novel models in the imitation of oral tissues/organs thus far,and reveals the limitations that TOOCs ***,it suggests further perspectives for future applications.

摘要：Using a suitable solvent for extracting pigments from sediment for high performance liquid chromatography（HPLC） analysis is critical for obtaining qualitative and quantitative estimates of phytoplanktonic and benthic algal biomass,as well as community composition. Five methodological factors（sample dehydration,extraction solvent,extraction duration,number of extractions,and ratio of solvent volume：sample weight） were studied using an L 9（3 4 ） orthogonal design in a sedimentary pigment extraction experiment on samples collected from the Changjiang large-river delta-front estuary（LDE）,using HPLC analysis. The results show that the optimal extraction method for sedimentary pigments should include freeze-drying samples prior to extraction. The effects of different factors on sedimentary pigment extraction were separated by the L 9（3 4 ） orthogonal design experiments and showed that the extraction solvent was the most important,with extraction duration the second most important,and numbers of extraction and ratio of solvent volume：sample weight was the least important. The mixed solvent treatment comprised of acetone,methanol and water（80：15：5,by volume） was best for polar pigment extraction,with 100% acetone better for apolar pigments. For most pigments employed in this study（i.e.,peridinin,fucoxanthin,alloxanthin,diatoxanthin,zeaxanthin,pheophytin-a and β-carotene） ,3 h was found to be enough time for extraction from these deltaic sediments. However,for chlorophyll-a,the most important pigment used for estimating algal biomass,12 h was needed. A small amount of solvent（3 ml） with duplicate extractions obtained the greatest amount and diversity of pigments. Unfortunately,no extraction method was found to be suitable for all pigments in sediments. The choice of extraction procedure should be made in accordance with the objective of each study,taking into consideration the properties of sediments and pigments in question.