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Bile acids:Chemistry,physiology,and pathophysiology

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World journal of Gastroenterology 2009年第7期15卷 804-816页

作者： Maria j Monte jose jG Marin Alvaro Antelo jose Vazquez-Tato Laboratory of Experimental Hepatology and Drug Targeting CIBERehdUniversity of Salamanca Facultad de Ciencias Departamento de Quimica FisicaCampus of LugoUniversity of Santiago

The family of bile acids includes a group of molecular species of acidic steroids with very peculiar physical-chemical and biological *** are synthesized by the liver from cholesterol through several complementary pathways that are controlled by mechanisms involving finetuning by the levels of certain bile acid *** their best-known role is their participation in the digestion and absorption of fat,they also play an important role in several other physiological ***,genetic abnormalities accounting for alterations in their synthesis,biotransformation and/or transport may result in severe alterations,even leading to lethal situations for which the sole therapeutic option may be liver ***,the increased levels of bile acids reached during cholestatic liver diseases are known to induce oxidative stress and apoptosis,resulting in damage to the liver parenchyma and,eventually,extrahepatic *** this occurs during pregnancy,the outcome of gestation may be *** contrast,the physical-chemical and biological properties of these compounds have been used as the bases for the development of drugs and as pharmaceutical tools for the delivery of active agents.

关键词： Cholestasis Cholesterol Liver Metabolism Transport

Abscisic Acid, High-Light, and Oxidative Stress Down-Regulate a Photosynthetic Gene via a Promoter Motif Not Involved in Phytochrome- Mediated Transcriptional Regulation

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Molecular Plant 2008年第1期1卷 75-83页

作者： Roberto j. Staneloni Maria jose Rodriguez-Batiller jorge j. Casal Fundacion Instituto Leloir and IIBBA-CONICET C1405BWE-Buenos Aires Argentina IFEVA Facultad de Agronomia Universidad de Buenos Aires and CONICET 1417 Buenos Aires Argentina

In etiolated seedlings, light perceived by phytochrome promotes the expression of light-harvesting chlorophyll a/b protein of photosystem Ⅱ （Lhcb） genes. However, excess of photosynthetically active radiation can reduce Lhcb expression. Here, we investigate the convergence and divergence of phytochrome, high-light stress and abscisic acid （ABA） signaling, which could connect these processes. Etiolated Arabidopsis thaliana seedlings bearing an Lhcb promoter fused to a reporter were exposed to continuous far-red light to activate phytochrome and not photosynthesis, and treated with ABA. We identified a cis-acting region of the promoter required for down-regulation by ABA. This region contains a CCAC sequence recently found to be necessary for ABI4-binding to an Lhcb promoter. However, we did not find a G-box-binding core motif often associated with the ABI4-binding site in genes promoted by light and repressed by ABI4. Mutations involving this motif also impaired the responses to reduced water potential, the response to high photosynthetic light and the response to methyl viologen but not the response to low temperature or to Norflurazon. We propose a model based on current and previous findings, in which hydrogen peroxide produced in the chloroplasts under high light conditions inter- acts with the ABA signaling network to regulate Lhcb expression. Since the mutation that affects high-light and methyl viologen responses does not affect phytochrome-mediated responses, the regulation by retrograde and phytochrome signaling can finally be separated at the target promoter level.

关键词： Abscisic Acid High-Light Oxidative Stress Down-Regulate Photosynthetic Gene

On the Structure of Graded Leibniz Algebras

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Algebra Colloquium 2015年第1期22卷 83-96页

作者： Antonio j. Calderon Martin jose M. Sfinchez Delgado Departamento de Matemdticas Universidad de Cadiz 11510 Puerto Real Cadiz Spain

We study the structure of graded Leibniz algebras with arbitrary dimension and over an arbitrary base field K. We show that any of such algebras ￡ with a symmetric G-support is of the form ￡ = U-∑jIj with U a subspace of ￡1, the homogeneous component associated to the unit element 1 in G, and any Ij a well described graded ideal of ￡, satisfying [Ij, Ik]= 0 if j≠ k. In the case of ￡ being of maximal length, we characterize the gr-simplicity of the algebra in terms of connections in the support of the grading.

关键词： graded Leibniz algebra infinite dimensional Leibniz algebra structure theory

Hormonal control of seasonal color change in female spiny-footed lizards:an observational and experimental approach

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Current Zoology 2019年第6期65卷 633-642页

作者： Belen FRESNILLO josabel BELLIURE Diego GIL jose j.CUERVO Department of Life Sciences Ecology SectionUniversity of AlcalaMadridSpain Department of Functional and Evolutionary Ecology Estacion Experimental de Zonas Aridas(CSIC)Carretera de Sacramento s/nAlmerfaSpain Department of Evolutionary Ecology Museo Nacional de Ciencias Naturales(CSIC)MadridSpain

Breeding coloration of females often signals aspects of their reproductive status,suggesting a link between color and sex steroid *** this study,we examined the relationships between 2 sex steroid hormones(progesterone and p-estradiol)and reproductive coloration in female spinyfooted lizards Acanthodactylus *** first explored natural variation in female plasma hormone levels and coloration during their reproductive cycle,p-estradiol was negatively related to brightness and positively related to red saturation,whereas progesterone was not significantly related to *** identifying key relationships,plasma hormone concentrations were manipulated by creating 3 experimental female groups(p-estradiol-treated,progesterone-treated,and control),and the effects on coloration were monitored,p-estradiol-treated females,in which there was a rise in both p-estradiol and progesterone levels,lost their red coloration earlier than females in the other 2 experimental groups,whereas progesterone treatment had no significant effect on female *** results suggest that high levels of either p-estradiol alone or(3-estradiol together with progesterone trigger the loss of red coloration in female spiny-footed lizards,and that progesterone alone does not affect *** hypothesize that changes in female breeding color might be regulated by(3-estradiol in species in which conspicuous coloration is displayed before ovulation,and by progesterone in species in which this color is displayed during gravidity.

关键词： color signaling enzyme immunoassay hormone-induced color change sex-specific coloration spectrophotometry transdermal hormone application

Cell Wall Microstructure Analysis Implicates Hemicellulose Polysaccharides in Cell Adhesion in Tomato Fruit Pericarp Parenchyma

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Molecular Plant 2009年第5期2卷 910-921页

作者： jose j. Ordaz-Ortiz Susan E. Marcus j. Paul Knox Centre for Plant Sciences Faculty of Biological Sciences University of Leeds Leeds LS2 9JT United Kingdom

Methods developed to isolate intact cells from both unripe and ripe tomato fruit pericarp parenchyma have allowed the cell biological analysis of polysaccharide epitopes at the surface of separated cells. The LM7 pectic homogalacturonan epitope is a marker of the junctions of adhesion planes and intercellular spaces in parenchyma systems. The LM7 epitope persistently marked the former edge of adhesion planes at the surface of cells separated from unripe and ripened tomato fruit and also from fruits with the Cnr mutation. The LM 11 xylan epitope was associated, in sections, with cell walls lining intercellular space but the epitope was not detected at the surface of isolated cells, being lost during cell isolation. The LM15 xyloglucan epitope was present at the surface of cells isolated from unripe fruit in a pattern reflecting the former edge of cell adhesion planes/intercellular space but with gaps and apparent breaks. An equivalent pattern of LM15 epitope occurrence was revealed at the surface of cells isolated by pectate lyase action but was not present in cells isolated from ripe fruit or from Cnr fruit. In contrast to wild-type cells, the LM5 galactan and LM21 mannan epitopes occurred predominantly in positions reflecting intercellular space in Cnr, suggesting a concerted alteration in cell wall microstructure in response to this mutation. Galactanase and mannanase, along with pectic homogalacturonan-degrading enzymes, were capable of releasing cells from unripe fruit parenchyma. These observations indicate that hemicellulose polymers are present in architectural contexts reflecting cell adhesion and that several cell wall polysaccharide classes are likely to contribute to cell adhesion/cell separation in tomato fruit pericarp parenchyma.

关键词： Cell walls fruit development tomato cell adhesion cell separation polysaccharide.

Mercury uptake and effects on growth in jatropha curcas

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journal of Environmental Sciences 2016年第10期28卷 120-125页

作者： jose Marrugo-Negrete jose Durango-Hernandez jose Pinedo-Hernandez German Enamorado-Montes Sergi Diez University of Cordoba Faculty of Basic Sciences Department of Chemistry Water Applied and Environmental Chemistry Group Monteria Colombia Environmental Chemistry Department Institute of Environmental Assessment and Water Research ID█A-CSIC E-08034 Barcelona Spain

The use of metal-accumulating plants for the phytoremediation of contaminated soils is gaining more attention. Mercury （Hg）-contaminated soils from historical gold mines represent a potential risk to human health and the environment. Therefore, jatropha curcas plant, that has shown its tolerance to these environments, is a species of particular interest to implement phytoremediation techniques in gold mining sites. In this work, the behavior of j. curcas was assessed in different hydroponic cultures fortified with Hg at concentrations of 5, 10, 20, 40, and 80μg Hg/mL （T5, T10, T20, T40 and T80, respectively）. After exposure, plant growth, net photosynthesis, leaf area, and Hg accumulation were determined and variables such as net Hg uptake, effective Hg accumulation, translocation and bioaccumu- lation factors were calculated. Accumulation of Hg in root and leaf tissues increased with respect to the Hg concentrations in the hydroponic culture, with statistically significant differences （p 〈 0.05） among treatments. Moreover, Hg concentration in roots was 7 and 12-fold higher in average than in plant leaves and shoots, respectively. Many effects were found in the development of plants, especially related with loss of biomass and leaf area, with significant growth inhibition related to control values （〉50% with treatment T5）. Moreover, percentage of inhibition was even higher （〉60%） with same treatment for net photosynthesis. Finally, it should be highlighted that for T40 and T80 treatments, plant growth and photosynthesis were almost completely depleted （88%-95%）.

关键词： jatropha curcasPhytoextractionMercuryHydroponicGrowth inhibition

Comparative study of degradation of toluene and methyl isobutyl ketone(MIBK)in aqueous solution by pulsed corona discharge plasma

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journal of Environmental Sciences 2021年第3期33卷 382-396页

作者： jerin jose Ligy Philip Department of Civil Engineering Indian Institute of Technology MadrasChennai 600036India

Effectiveness of pulsed power plasma for the degradation of two toxic volatile organic compounds(VOCs),toluene and methyl isobutyl ketone(MIBK),in aqueous solution was *** plasma degradation of MIBK has been studied for the first *** influence of initial concentration of target compound,solution pH and scavengers on percentage degradation was evaluated.100%removal of 200 mg/L of toluene and MIBK was achieved both in liquid and gaseous phases after 12 and 16 min of plasma treatment,*** first order rate constant of toluene and MIBK degradation(for 200 mg/L each)was 0.421 and 0.319 min~(-1)respectively when they were treated individually,and these values decreased slightly during degradation of their *** degradation was slower than toluene and it might be due to semi volatile and hydrophilic nature of *** effect of initial concentration of toluene and MIBK showed different degradation *** degradation of both the compounds was obtained in neutral pH and in absence of scavengers.·OH radical was the major reactive species involved in their *** degradation in real environmental matrices showed that removal reduced significantly in secondary effluent due to scavenging of reactive species by various ions and organic *** total number of degradation intermediates identified in case of toluene and MIBK was 11 and 14 respectively and formate was the one recalcitrant byproduct *** degradation pathway of toluene and MIBK involving reactions of reactive oxygen and nitrogen species and reductive species is proposed.

关键词： Degradation pathway Methyl isobutyl ketone(MIBK) OH radical Pulsed power plasma Toluene

Complex interactions between biota, landscapes and native peoples

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Ecological Processes 2013年第1期2卷 297-299页

作者： jose MV Fragoso Nicholas j Reo Department of Biology Stanford UniversityStanfordCAUSA Environmental Studies Program Dartmouth CollegeHanoverNHUSA

The papers presented here originated with a symposium held at the Ecological Society of America’s annual meeting in Portland,Oregon,in *** describe how native people and indigenous researchers view and understand the cultural and biological complexity inherent in coupled socio-ecological *** researchers note that interactions between native peoples and their environments consist of a complex network of linkages,feedbacks,and change,and they describe synthetic approaches to problem *** approaches often spring from long cultural traditions and recent adaptations to *** are examples of native peoples successfully managing biota and ecosystems for thousands of ***,current societal conditions often challenge indigenous-based efforts to continue managing ecosystems and ***,in the face of the new challenges native people continue to innovate and manage their environments and biota.

关键词： continue environments landscape

Performance of unique and secure routing protocol(USRP)in flying Adhoc Networks for healthcare applications

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High-Confidence Computing 2024年第1期4卷 24-31页

作者： j.Vijitha Ananthi P.Subha Hency jose Department of Biomedical Engineering Karunya Institute of Technology and SciencesCoimbatoreIndia

Nowadays,Flying Adhoc Networks play a vital role due to its high efficiency in fast *** aerial vehicles transmit data much faster than other networks and are useful in all aspects of *** healthcare applications,wireless body area network transmits the data,whereas the security,which is the most important concern to be focused in a flying adhoc network is not *** intruders tamper the network,degrading the overall network *** avoid security issues,a unique and secure routing protocol that provides a single solution for five different types of attacks such as,black hole attacks,grey hole attacks,yoyo attacks,conjoint attack and jamming attacks,is *** simulation results analyses the network performance by using the proposed routing *** comparison to the other solutions rendered to resolve the affected network,this proposed routing protocol has a higher throughput,higher delivery rate,and lower *** Unique and Secure Routing Protocol(USRP)provides an integrated solution for an efficient and secure communication in a flying adhoc network.

关键词： Secure routing protocol Flying Adhoc Networks Unmanned aerial vehicles Mobile Adhoc network Attackers Denial of service attacks