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Rickettsia influences thermotolerance in the whitefly Bemisia tabaci B biotype

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Insect Science 2011年第1期18卷 57-66页

作者： marina Brumin Svetlana Kontsedalov Murad Ghanim Department of Entomology Institute of Plant Protection the Volcani Center Bet Dagan Israel

The whitefly Bemisia tabaci harbors Portiera aleyrodidarum, an obligatory symbiotic bacterium, as well as several secondary symbionts, including Rickettsia, Hamiltonella, Wolbachia, Arsenophonus, Cardinium and Fritschea, the function of which is unknown. In Israel, Rickettsia is found in both the B and Q ofB. tabaci biotypes, and while all other secondary symbionts are located in the bacteriomes, Rickettsia can occupy most of the body cavity of the insect. We tested whether Rickettsia influences the biology of B. tabaci and found that exposing a Rickettsia-containing population to increasing temperatures significantly increases its tolerance to heat shock that reached 40~C, compared to a Rickettsia-free population. This increase in tolerance to heat shock was not associated with specific induction of heat-shock protein gene expression; however, it was associated with reduction in Rickettsia numbers as was assessed by quantitative real-time polymerase chain reaction and fluorescence in situ hybridization analyses. To assess the causes for thermotolerance when Rickettsia is reduced, we tested whether its presence is associated with the induction of genes required for thermotolerance. We found that under normal 25℃ rearing temperature, genes associated with response to stress such as cytoskeleton genes are induced in the Rickettsia-containing population. Thus, the presence of Rickettsia in B. tabaci under normal conditions induces the expression of genes required for thermotolerance that under high temperatures indirectly lead to this tolerance.

关键词： cytoskeleton gene expression heat shock symbiont

Silver impregnated carbon for adsorption and desorption of elemental mercury vapors

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Journal of Environmental Sciences 2011年第9期23卷 1578-1583页

作者： Despina Karatza marina Prisciandaro Amedeo Lancia Dino Musmarra Dipartimento di Ingegneria Chimica Universitàdi Napoli "Federico II" Dipartimento di Chimica Ingegneria Chimica e MaterialiUniversitàde L’Aquila Centro Interdipartimentale di Ricerca in Ingegneria Ambientale Dipartimento di Ingegneria CivileSeconda Universitàdegli Studi di NapoliReal Casa dell’AnnunziataVia Roma 2981031 Aversa (CE)Italy

The Hg 0 vapor adsorption experimental results on a novel sorbent obtained by impregnating a commercially available activated carbon （Darco G60 from BDH） with silver nitrate were *** study was performed by using a fundamental approach,in an apparatus at laboratory scale in which a synthetic flue gas,formed by Hg 0 vapors in a nitrogen gas stream,at a given temperature and mercury concentration,was flowed through a fixed bed of adsorbent *** curves and adsorption isotherms were obtained for bed temperatures of 90,120 and 150°C and for Hg 0 concentrations in the gas varying in the range of 0.8–5.0 mg/m 3 .The experimental gas-solid equilibrium data were used to evaluate the Langmuir parameters and the heat of *** experimental results showed that silver impregnated carbon was very effective to capture elemental mercury and the amount of mercury adsorbed by the carbon decreased as the bed temperature *** addition,to evaluate the possibility of adsorbent recovery,desorption was also *** runs showed that both the adsorbing material and the mercury could be easily recovered,since at the end of desorption the residue on solid was almost *** material balance on mercury and the constitutive equations of the adsorption phenomenon were integrated,leading to the evaluation of only one kinetic parameter which fits well both the experimentally determined breakthrough and desorption curves.

关键词： mercury carbon MSW incinerators adsorption desorption silver nitrate

Charged Scalars in Transient Stellar Electromagnetic Fields

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Chinese Physics Letters 2011年第1期28卷 20-23页

作者： marina-Aura Dariescu Ciprian Dariescu Ovidiu Buhucianu Faculty of Physics A1. I. Cuza' University Bd. Carol I No. 11 700506 Iaoi Romania

We consider a non-rotating strongly magnetized object, whose magnetic induction is of the form Bx= Bo （t） sin kz. In the electromagnetic field generated by only one component of the four-vector potential, we solve the Klein- Gordon equation and discuss the sudden growth of the scalar wave functions for wavenumbers inside computable ranges. In the case of unexcited transversal kinetic degrees, we write down the recurrent differential system for the amplitude functions and compute the respective conserved eurrents.

关键词： Astrophysics and astroparticles

An Experimental Investigation of the Dissipation Mechanisms in the Suction Side Boundary Layer of a Turbine Blade

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Journal of Thermal Science 2008年第4期17卷 289-297页

作者： Francesca Satta Daniele Simoni marina Ubaldi Pietro Zunino Dipartimento di Macchine Sistemi Energetici e Trasporti-Università di Genova

The present work is part of an extensive experimental activity carried out by the authors in recent years aimed at investigating the boundary layer transition phenomenon in turbine blades. The large scale of the cascade and the use of advanced LDV instrumentation and precision probe traversing mechanism resulted in high degree of spatial resolution and high accuracy of measurements. The main dissipation mechanism determining the profile losses in turbomachinery blades is the work of deformation of the mean motion within the boundary layer operated by both viscous and turbulent shear stresses. In the present paper, the local viscous and turbulent deformation works have been directly evaluated from the detailed measurements of boundary layer mean velocity and Reynolds shear stress. The results show the distributions and the relative importance of the viscous and turbulent contributions to the loss production, in relation with the boundary layer states occurring along the turbine profile.

关键词： Axial flow turbines Profile boundary layer Energy dissipation mechanism Boundary layer transition Laser Doppler measurements.

Utilization of molecular genetic approaches for colorectal cancer screening

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World Journal of Gastroenterology 2024年第46期30卷 4950-4957页

作者： marina A Emelyanova Anna Y Ikonnikova Center for Precision Genome Editing and Genetic Technologies for Biomedicine Engelhardt Institute of Molecular BiologyRussian Academy of SciencesMoscow 119991Russia

The feasibility of population screening for colorectal cancer has been demonstrated in several *** of these studies have considered individual characteristics,diagnostic approaches,epidemiological data,and socioeconomic *** this article,we comment on an editorial by Metaxas et al published in the recent issue of the *** authors emphasized the need to raise public awareness through health education programs and the possibility of using easily accessible non-invasive screening ***,we focus on non-invasive molecular genetic approaches that can aid in colorectal cancer *** the one hand,we highlighted the use of tumor DNA/RNA markers directly for screening and,on the other hand,underline the use of polygenic risk assessment and hereditary predisposition to select individuals for more thorough cancer screening.

关键词： Colorectal cancer Cancer screening Non-invasive screening Liquid biopsy Polygenic risk score

Population specific fitness response of Drosophila subobscura to lead pollution

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Insect Science 2013年第2期20卷 245-253页

作者： Bojan Kenig marina Stamenkovic-Radak Marko Andelkovic Institute for Biological Research Sinia Stankovic University of Belgrade Faculty of Biology University of Belgrade Serbian A cademy of Sciences and Arts Belgrade Serbia

Differences in heavy metal tolerance among separate populations of the same species have often been interpreted as local adaptation. Persistence of differences after removing the stressor indicates that mechanisms responsible for the increased tolerance were genetically determined. Drosophila subobscura Collin （Diptera： Drosophilidae） pop- ulations were sampled from two localities with different history of heavy metal pollution, and reared for eight generations in the laboratory on a standard medium and on media with different concentrations of lead （Pb）. To determine whether flies from different natural populations exposed to the Pb-contaminated media in the laboratory show population spe- cific variability in fitness components over generations, experimental groups with different concentrations of lead were assayed in three generations （F2, Fs, and Fs） for fecundity, de- velopmental time, and egg-to-adult viability. On the contaminated medium, fecundity was reduced in later generations and viability was increased, irrespective of the environmental origin of populations. For both populations, developmental time showed a tendency of slowing down on media with lead. Faster development was observed in later generations. Preadaptation to contamination, meaning higher fecundity, higher viability, and faster egg to adult development in all studied generations, was found in D. subobscura originating from the locality with a higher level of heavy metal pollution,

关键词： environmental background fitness components heavy metal interpopulation differences laboratory evolution local adaptation

Tunneling of Relativistic Bosons Induced by Magnetic Fields in the Magnetar’s Crust

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Chinese Physics Letters 2015年第10期32卷 26-29页

作者： marina-Aura Dariescu Ciprian Dariescu Denisa-Andreea Mihu Faculty of Physics Alexandru Ioan Cuza University of Iasi Bd

The present work is devoted to the study of bosons evolving in the frozen magnetar＇s crust endowed with an ultra-strong magnetic field orthogonal to an electric field, both described by periodic functions. We discuss the quantum tunneling process through the one-dimensional potential barrier along Oz. The solutions to the Klein- Gordon equation are expressed in terms of Mathieu＇s functions which, for computable particle＇s energy range, are turning from oscillatory to exponentially growing modes along Oz. Within the Jeffreys Wentzel Kramers- Brillouin framework, the transmission coefficient is computed for the particle momentum in the middle of the instability range.

关键词： Tunneling of Relativistic Bosons Induced by Magnetic Fields in the Magnetar’s Crust

The bumpy road of purinergic inhibitors to clinical application in immune-mediated diseases

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Neural Regeneration Research 2024年第6期19卷 1206-1211页

作者： Matthias T.Wyss Christine Heuer marina Herwerth Institute of Pharmacology and Toxicology University of ZurichZürichSwitzerland Neuroscience Center Zurich(ZNZ) University of Zurich and ETH ZurichZürichSwitzerland Neurology Department University Hospital of ZurichZürichSwitzerland

Purinergic signaling plays important roles throughout the body in the regulation of organ functions during and following the disruption of *** is also reflected by the widespread expression of two families of purinergic receptors(P1 and P2)with numerous *** the last few decades,there has been increasing evidence that purinergic signaling plays an important role in the regulation of immune ***,signals mediated by P2 receptors have been shown to contribute to immune system-mediated ***,interference with P2 receptors may be a promising strategy for the modulation of immune *** only a few clinical studies have been conducted in isolated entities with limited success,preclinical work suggests that the use of P2 receptor inhibitors may bear some promise in various autoimmune *** the association of P2 receptors with several disorders from this field,the use of P2 receptor antagonists in clinical therapy is still very *** this narrative review,we briefly review the involvement of the purinergic system in immunological responses and clinical studies on the effect of purinergic inhibition on autoimmune *** then open the aperture a bit and show some preclinical studies demonstrating a potential effect of purinergic blockade on autoimmune *** suramin,a non-specific purinergic inhibitor,as an example,we further show that off-target effects could be responsible for observed effects in immunological settings,which may have interesting ***,we believe that it is worthwhile to further investigate this hitherto underexplored area.

关键词： autoimmune diseases neurological disorders purinergic system P2 receptor inhibitors suramin

Sediment regime of the Danube River in Serbia

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International Journal of Sediment Research 2013年第4期28卷 470-485页

作者： marina BABIC MLADENOVIC Vasiljka KOLAROV Vanja DAMJANOVIC Jaroslav Cerni Institute for the Development of Water Resources Department for River Engineering

The total length of the Danube section in Serbia is 587.5 km,and it has three specific sections:(1) Pannonian Plain Danube(or the Middle Danube) has all characteristics of lowland *** stretch downstream of Novi Sad is under the influence of the Iron Gate 1 backwater during low water flows;(2) Iron Gate Danube,where the river is confined in the *** it is a reservoir,with completely altered natural characteristics.(3) Western Pontic Danube(or the Lower Danube),downstream of the *** paper presents the sediment regime in the Serbian sector of the Danube River,both upstream and within the Iron Gate *** field investigation data were used to describe the most important parameters of sediment transport and deposition processes,including riverbed composition and suspended sediment characteristics(grain size and concentration).The influence of large tributaries of the Danube(the Tisza,the Sava,and the Velika Morava) is also *** conducted in the Iron Gate 1reservoir under the Sediment Regime and Morphological Changes Monitoring Program is also *** obtained during implementation of the Program form the basis for the description of changes in the Danube sediment regime that occurred following erection of the Iron Gate *** revealed that the most important consequence of the Iron Gate I IIPNS Dam is permanent deposition of sediment in the Iron Gate Gorge portion of the reservoir,the water and environmental management implications of which are becoming increasingly ***,upstream stretches of the reservoir are not subject to uniform sedimentation processes;instead,the sediment regime depends on current hydrologic and hydraulic conditions within the watercourse and/or the hydro-power plant operating mode.

关键词： Sediment regime Morphological changes Danube Serbia