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The “sequential cues hypothesis”: a conceptual model to explain host location and ranking by polyphagous herbivores

Insect Science 2020年第6期27卷 1136-1147页

作者： Rehan Silva Anthony R.Clarke School of Earth.environmental and biological sciences Queensland University of Technology(QUT)BrisbaneQueenslandAustralia

Successfully locating a host plant is crucial for an insect herbivore to feed and/or ***,locating a host within a complex environment that may contain an array of different plant species is a difficult *** is particularly the case for polyphagous herbivores,which must locate a host within environments that may simultaneously contain multiple suitable and unsuitable *** we review the mechanisms of host selection used by polyphagous herbivores,as well as exploring how prior experience may modify a generalist's response to host *** show that recent research demonstrates that polyphagous herbivores have the capacity to detect both common cues from multiple host species,as well as specific cues from individual host *** creates a paradox in that generalists invariably rank hosts when given a choice,a finding at odds with the“neural limitations”hypothesis that says generalist insect herbivores should not have the neural capacity to identify cues specific to every possible *** explain this paradox we propose a model,akin to parasitoid host location,that postulates that generalist herbivores use different cues sequentially in host *** propose that initially common host cues,associated with all potential hosts,are used to place the herbivore within the host habitat and that,in the absence of any other host cues,these cues are sufficient in themselves to lead to host *** such they are true “generalist”***,once within the host habitat,we propose that the presence of a smaller group of cues may lead to further host searching and the location of preferred hosts:these are“specialist”*** model explains the current conflict in the literature where generalists can respond to both common and specific host-plant cues,while also exhibiting specialist and generalist host use behavior under different conditions.

关键词： diet breadth foraging insect behavior insect-plant relationship learning neural constraints visual cues volatile cues

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Wnt signaling in the nervous system and in Alzheimer＇s disease

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Journal of Molecular Cell Biology 2014年第1期8卷 64-74页

作者： Nibaldo C. Inestrosa Lorena Varela-Nallar Center for Aging and Regeneration (CARE) Department of Cell and Molecular Biology Faculty of Biological Sciences Pontifical Catholic University of ChileSantiago Chile Center for Biomedical Research Faculty of Biological Sciences and Faculty of Medicine AndrOs Bello University Santiago Chile

Wnts comprise a large family of proteins that have shown to be part of a signaling cascade that regulates several aspects of develop- ment including organogenesis, mid brain development as welt as stem cell proliferation. Wnt signaling pathway plays different roles in the development of neuronal circuits and also in the adult brain, where it regulates synaptic transmission and plasticity. It has been also implicated in various diseases including cancer and neurodegenerative diseases, reflecting its relevance in fundamental biological pro- cesses. This review summarizes the progress about Wnts function in mature nervous system with a focus on Alzheimer＇s disease （AD）. We discuss the prospects of modulating canonical and non-canonical Wnt signaling as a strategy for neuroprotection. This will include the potential of Wnts to：（i） act as potent regulators of hippocampai synapses and impact in learning and memory; （ii） regulate adult neurogenesis; and finally （iii） control AD pathogenesis.

关键词： Wnt glutamate Alzheimer's disease synapses dendritic spines neuroprotection

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Types of voltage-dependent calcium channels involved in high potassium depolarization-induced amylase secretion in the exocrine pancreatic tumour cell line AR4-2J

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Cell Research 1998年第1期8卷 23-31页

作者： CUI ZONG JIE (Beijing Agricultural University faculty of biological sciences Beijing 100094, China) Beijing Agricultural University faculty of biological sciences China

In the perifused fura-2 loaded exocrine pancreatic acinar cell line AR4-2J pulses of high potassium induced repetitive increases in intracellular calcium. Attached cells when stimulated with high potassium secreted large amount of amylase. High potassium-induced secretion was dependent both on the concentration of potassium and duration of stimulation. High potassium induced increases in intracellular calcium were inhibited by voltage-dependent calcium channel antagonists with an order of potency as follows: nifedipine > ω-agatoxin IVA > ω-conotoxin GVIA. In contrast, the L-type calcium channel antagonist nifedipine almost completely inhibited potassium-induced amylase secretion, whereas the N-type channel antagonist ω-conotoxin GVIA was without effect. The P-type channel antagonist ω-agatoxin IVA had a small inhibitory effect, but this inhibition was not significant at the level of amylase secretion. In conclusion, the AR4-2J cell line possesses different voltage-dependent calcium channels (L, P,N) with the L-type predominantly involved in depolarization induced amylase secretion.

关键词： AR4-2J pancreatic acinar cells amylase secretion calcium channels

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Non-aqueous extracts of Curcuma mangga rhizomes induced cell death in human colorectal adenocarcinoma cell line(HT29) via induction of apoptosis and cell cycle arrest at G_0/G_1 phase

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Asian Pacific Journal of Tropical Medicine 2016年第1期9卷 8-15页

作者： Gin Wah Hong Sok Lai Hong Guan Serm Lee Hashim Yaacob Sri Nurestri Abd Malek Institute of biological sciences Faculty of ScienceUniversity of Malaya Meritus University

Objective:To investigate the cytotoxic activity of the hexane and ethyl acetate extracts of Curcuma mangga rhizomes against human colorectal adenocarcinoma cell lines(HT29).Methods:The cytotoxic activity of the hexane and ethyl acetate extracts of Curcuma mangga rhizomes against human colorectal adenocarcinoma cell lines(HT29) was determined by using the SRB ***:The ethyl acetate extract showed a higher cytotoxic effect compared to the hexane *** changes of the HT29 cells such as cell shrinkage,membrane blebbling and formation of apoptotic bodies while changes in nuclear morphology like chromatin condensation and nuclear fragmentation were *** evidence of apoptosis in HT29 cells was further supported by the externalization of phosphatidylserine which indicate early sign of ***:The early sign of apoptosis is consistent with the cell cycle arrest at the G_0/G_1 checkpoint which suggests that the changes on the cell cycle lead to the induction of apoptosis in HT29.

关键词： Curcuma mangga Anticancer Apoptosis Cell cycle arrest HT29

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Efficient purification of Al_(30) by organic complexation method

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Journal of environmental sciences 2019年第6期31卷 240-247页

作者： Libing Liu Qinxue Yang Pin Wang Feng Xiao Ruyuan Jiao Guangyu An Dongsheng Wang University of Chinese Academy of sciences State Key Laboratory of environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences faculty Materials Science and Chemistry China University of Geosciences

A method was developed for preparing high purity Al30O8(OH)56(H2O)_(24)^(18)+(Al30) through elimination of impurities by *** chloride II(PAC_(30))with Al_(c )content of 75%was adopted as the source of Al_(30).The PAC_(30)was prepared under conditions of total aluminum concentration 0.1 mol/L and OH^-/Al ratio 2.2 to obtain the highest content of Al_(30).A precipitation/metathesis method,organic solvent precipitation method and organic complexation method were examined to separate and purify Al_(30).It was found that only by the organic complexation method could high purity Al_(30)products be obtained in large yield *** the experiments,benzoic acid was used as the coordinating reagent to decompose the main impurity AlO_4Al_(12)(OH)_(24)(H_2O)_(12)^(7+)(Al_(13)),and the Al_(30)product could be obtained by precipitation and metathesis *** was noteworthy that the decomposition of impurities by benzoic acid could be completed in 2 *** Al_(30)product was characterized by Ferron assay,^(27)Al-NMR,SEM,XRD and *** results showed that the purity of the Al_(30)product could exceed 92%.

关键词： Polyaluminum chloride(PAC) Al13 Al30 Organic complexation Precipitation/metathesis

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Mercury in alpine fish from four rivers in the Tibetan Plateau

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Journal of environmental sciences 2016年第1期28卷 22-28页

作者： Junjuan Shao Jianbo Shi Bu Duo Chengbin Liu Yan Gao Jianjie Fu Ruiqiang Yang Guibin Jiang State Key Laboratory of environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences Science faculty Tibet University

As a global pollutant, high levels of mercury（Hg） have been found in remote ecosystem due to the long range atmospheric transport. In this study, a total of 60 fish samples were collected from four rivers across the Tibetan Plateau to study the accumulation of Hg in remote and high-altitude aquatic environment. The total Hg（THg） and methylmercury（MeHg） in fish muscles ranged from 11 to 2097 ng/g dry weight（dw）（average： 819 ng/g dw）and from 14 to 1960 ng/g dw（average： 756 ng/g dw）, respectively. Significantly positive linear relationships were observed between the THg（r = 0.591, p 〈 0.01, n = 36） and MeHg concentrations（r = 0.473, p 〈 0.01, n = 36） with the trophic level of fish from Lhasa River,suggesting trophic transfer and biomagnification of Hg in this aquatic ecosystem. Moreover,the THg levels in fish had significantly positive correlations with the length（r = 0.316,p 〈 0.05, n = 60） and weight（r = 0.271, p 〈 0.05, n = 60） of fish. The high levels of Hg were attributed to the slow growth and long lifespan of the fish under this sterile and cold environment. Risk assessment revealed that the consumption of Oxygymnocypris stewartii,Schizothorax macropogon, Schizothorax waltoni, Schizopygopsis younghusbandi and Schizothorax o＇connori would lead to a high exposure to Me Hg.

关键词： Mercury Methylmercury Fish The Tibetan Plateau Trophic level Risk assessment

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Photocatalytic activity of TiO2 containing anatase nanoparticles and rutile nanoflower structure consisting of nanorods

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Journal of environmental sciences 2013年第12期25卷 2460-2468页

作者： Zhiqiao He Qiaolan Cai Huiying Fang Gaohua Situ Jianping Qiu Shuang Song Jianmeng Chen College of biological and environmental Engineering Zhejiang University of Technology

A series of TiO2 with different crystal phases and morphologies was synthesized via a facile hydrothermal process using titanium nbutoxide and concentrated hydrochloric acid as raw materials. The photocatalytic activity of the samples was evaluated by degradation of Methyl Orange in aqueous solution under UV-Visible light irradiation. On the basis of detailed analysis of the characterizing results of high-resolution transmission electron microscopy, X-ray powder diffraction measurements, X-ray photoelectron spectroscopy and Brunauer-Emmett-Teller measurement, it was concluded that the photo-activity of the catalyst is related directly to the 3D morphology and the crystal phase composition. An excellent catalyst should have both a futile 3D flower-like structure and anatase granulous particles. The 3D flower-like structure could enhance light harvesting, as well as the transfer of reactant molecules from bulk solution to the reactive sites on TiO2. In addition, the optimum anatase/rutile phase ratio was found to be 80：20, which is beneficial to the effective separation of the photogenerated electron-hole pairs.

关键词： photocatalysis TiO2 anatase nanoparticles rutile nanoflowers simulated solar light illumination.

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Comparison of the toxicity of silver nanoparticles and silver ions on the growth of terrestrial plant model Arabidopsis thaliana

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Journal of environmental sciences 2013年第9期25卷 1947-1955页

作者： Haifeng Qian Xiaofeng Peng Xiao Han Jie Ren Liwei Sun Zhengwei Fu College of biological and environmental Engineering Zhejiang University of Technology

Silver nanoparticles （AgNPs） are one of the most widely used nanomaterials, but the mechanism of AgNP toxicity in terrestrial plants is still unclear. We compared the toxic effects of AgNPs and Ag＋ on Arabidopsis thaliana at the physiological, ultrastructural and molecular levels. AgNPs did not affect seed germination; however, they showed stronger inhibitory effect on root elongation than Ag＋ . The results of transmission electron microscopy and metal content analysis showed that AgNPs could be accumulated in leaves. These absorbed AgNPs disrupted the thylakoid membrane structure and decreased chlorophyll content, which can inhibit plant growth. By comparison, a small amount of Ag＋ was absorbed by seedlings, and it did not pronouncedly affect chloroplast structure and other metal ion absorption as AgNPs did. Compared with Ag＋ , AgNPs could alter the transcription of antioxidant and aquaporin genes, indicating that AgNPs changed the balance between the oxidant and antioxidant systems, and also affected the homeostasis of water and other small molecules within the plant body. All the data from physiological, ultrastructural and molecular levels suggest that AgNPs were more toxic than Ag＋ .

关键词： silver nanoparticles Ag+ Arabidopsis thaliana gene transcript antioxidant enzyme aquaporins

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Facies Analysis and Sequence Stratigraphy of the Qal'eh Dokhtar Formation(Middle-Upper Jurassic) in the West of Boshrouyeh, East Central Iran

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Acta Geologica Sinica(English Edition) 2017年第5期91卷 1797-1819页

作者： Mahnaz SABBAGH BAJESTANI Asadollah MAHBOUBI Reza MOUSSAVI-HARAMI Ihsan AL-AASM Mehdi NADJAFI Department of Geology Faculty of Sciences Ferdowsi University of Mashhad Department of Earth and environmental sciences University of Windsor

The study area is located in the east Tabas Block in Central Iran. Facies analysis of the Qal＇eh Dokhtar Formation（middle Callovian to late Oxfordian） was carried out on two stratigraphic sections and applied to depositional environment and sequence stratigraphy interpretation. This formation conformably overlies and underlies the marly-silty Baghamshah and the calcareous Esfandiar formations, respectively. Lateral and vertical facies changes documents low-to high energy environments, including tidal-flat, beach to intertidal, lagoon, barrier, and open-marine. According to these facies associations and absence of resedimentation deposits a depositional model of a mixed carbonate-siliciclastic ramp was proposed for the Qal＇eh Dokhtar Formation. Seven third-order depositional sequences were identified in each two measured stratigraphic sections. Transgressive systems tracts（TSTs） show deepening upward trends, i.e. shallow water beach to intertidal and lagoonal facies, while highstand systems tracts（HST） show shallowing upward trends in which deep water facies are overlain by shallow water facies. All sequence boundaries（except at the base of the stratigraphic column） are of the no erosional（SB2） types. We conclude eustatic rather than tectonic factors played a dominant role in controlling carbonate depositional environments in the study area.

关键词： Sequence stratigraphy Qal9eh Dokhtar Formation mixed sUiciclastic-carbonate ramp Jurassic Central Iran

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Temperature Responses to Infrared-Loading and Water Table Manipulations in Peatland Mesocosms

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Journal of Integrative Plant Biology 2008年第11期50卷 1484-1496页

作者： Jiquan Chen Scott Bridgham Jason Keller John Pastor Asko Noormets Jake F.Weltzin Department of environmental sciences University of Toledo Center for Ecology and Evolutionary Biology University of Oregon Smithsonian environmental Research Center Department of biological sciences University of Minnesota National Phenology Network

We initiated a multi-factor global change experiment to explore the effects of infrared heat loading （HT） and water table level （WL） treatment on soil temperature （T） in bog and fen peatland mesocosms. We found that the temperature varied highly by year, month, peatland type, soil depth, HT and WL manipulations. The highest effect of HT on the temperature at 25 cm depth was found in June for the bog mesocosms （3.34-4.27 ℃） but in May for the fen mesocosms （2.32-4.33 ℃） over the 2-year study period. The effects of WL in the bog mesocosms were only found between August and January, with the wet mesocosms warmer than the dry mesocosms by 0.48-2.03 ℃ over the 2-year study period. In contrast, wetter fen mesocosms were generally cooler by 0.16-3.87℃. Seasonal changes of temperatures elevated by the HT also varied by depth and ecosystem type, with temperature differences at 5 cm and 10 cm depth showing smaller seasonal fluctuations than those at 25 cm and 40 cm in the bog mesocosms. However, increased HT did not always lead to warmer soil, especially in the fen mesocosms. Both HT and WL manipulations have also changed the length of the non-frozen season.

关键词： global change infrared mesocosm peatlands warming experiment water table.

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