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Two intestinal microbiota-derived metabolites, deoxycholic acid and butyrate, synergize to enhance host defense peptide synthesis and alleviate necrotic enteritis

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Journal of Animal Science and Biotechnology 2024年第3期15卷 1158-1172页

作者： Dohyung M.Kim Jing Liu Melanie A.Whitmore isabel Tobin Zijun Zhao Guolong Zhang Department of Animal and Food Sciences Oklahoma State UniversityStillwaterOKUSA

Background Necrotic enteritis(NE)is a major enteric disease in poultry,yet effective mitigation strategies remain *** acid(DCA)and butyrate,two major metabolites derived from the intestinal microbiota,have independently been shown to induce host defense peptide(hDP)***,the potential synergy between these two compounds remains *** To investigate the possible synergistic effect between DCA and butyrate in regulating hDP synthesis and barrier function,we treated chicken hD11 macrophage cells and jejunal explants with DCA and sodium butyrate(NaB),either individually or in combination,for 24 ***,we performed RNA isolation and reverse transcrip-tion-quantitative PCR to analyze hDP genes as well as the major genes associated with barrier *** further determine the synergy between DCA and NaB in enhancing NE resistance,we conducted two independent trials with Cobb broiler *** each trial,the diet was supplemented with DCA or NaB on the day-of-hatch,followed by NE induction through sequential challenges with Eimeria maxima and Clostridium perfringens on d 10 and 14,*** recorded animal mortality after infection and assessed intestinal lesions on d *** impact of DCA and NaB on the microbiota in the ileum and cecum was evaluated through bacterial 16S rRNA gene *** We found that the combination of DCA and NaB synergistically induced multiple hDP genes in both chicken hD11 cells and jejunal ***,the gene for claudin-1,a major tight junction protein,also exhibited synergistic induction in response to DCA and ***,dietary supplementation with a combination of 0.75 g/kg DCA and 1 g/kg NaB led to a significant improvement in animal survival and a reduction in intestinal lesions compared to either compound alone in a chicken model of ***,the cecal microbiota of NE-infected chickens showed a marked decrease in SCFA-producing bacteria such as Bacteroides,F

关键词： Bile acids host defense peptides Metabolites Microbiome Necrotic enteritis Short-chain fatty acids

Twenty years of population dynamics in European beech-oak forest at their rear range margin anticipate changes in its structure and composition

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Forest Ecosystems 2024年第3期11卷 358-370页

作者： álvaro Rubio-Cuadrado Iciar Alberdi isabel Canellas Fernando Montes Jesús Rodríguez-Calcerrada Rosana López Guillermo G.Gordaliza María Valbuena-Carabana Nikos Nanos Ramón Perea Luis Gil Departamento de dinamica y gestion forestal Instituto de Ciencias Forestales(ICIFOR-INIA)CSICCtra.La Coruna km 7.528040MadridSpain Departamento de Sistemas y Recursos Naturales Escuela Tecnica Superior de Ingeniería de MontesForestal y del Medio NaturalUniversidad Politecnica de Madrid.Ciudad Universitaria s/n28040MadridSpain School of Forestry and Natural Environment Aristotle University of ThessalonikiUniversity Campus54124ThessalonikiGreece

There is an increasing interest in restoring degraded forests,which occupy half of the forest *** the forms of restoration,passive restoration,which involves the elimination of degrading factors and the free evolution of natural dynamics by applying minimal or no management,is gaining *** dynamics is difficult to predict due to the influence of multiple interacting factors such as climatic and edaphic conditions,composition and abundance of species,and the successional character of these ***,we study the natural dynamics of a mixed forest located in central Spain,which maintained an open forest structure,due to intensive use,until grazing and cutting were banned in the *** most frequent woody species in this forest are Fagus sylvatica,Quercus petraea,Quercus pyrenaica,Ilex aquifolium,Sorbus aucuparia,Sorbus aria and Prunus avium,with contrasting shade and drought *** species are common in temperate European deciduous forest and are found here near their southern distribution limit,except for *** order to analyze forest dynamics and composition,three inventories were carried out in 1994,2005 and *** results show that,despite the Mediterranean influence,the natural dynamics of this forest has been mainly determined by different levels of shade *** the abandonment of grazing and cutting,*** expanded rapidly due to its lower shade tolerance,whereas after canopy closure and forest densification,shade-tolerant species gained ground,particularly ***,despite its lower drought and late-frost *** the current dynamics continue,*** will overtake the rest of the species,which will be relegated to sites with shallow soils and steep ***,all the multi-centennial beech trees,which are undergoing a rapid mortality and decline process,will disappear.

关键词： Forest succession Secondary forest Woodland Mixed forest Competition Recruitment

Effect of high-Frequency Electric Field on Propagation of Electrostatic Wave in a Non-Uniform Relativistic Plasma Waveguide

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Plasma Science and Technology 2008年第3期10卷 278-283页

作者： kh.h.EL-ShORBAGY Plasma Physics and Nuclear Fusion Department Nuclear Research Center Atomic Energy Authority Cairo Egypt

The effect of a high frequency （hF） electric field on the propagation of electrostatic wave in a 2D non-uniform relativistic plasma waveguide is investigated. A variable separation method is applied to the two-fluid plasma model. An analytical study of the reflection of electrostatic wave propagation along a magnetized non-uniform relativistic plasma slab subjected to an intense hF electric field is presented and compared with the case of a non relativistic plasma. It is found that, when the frequency of the incident wave is close to the relativistic electron plasma frequency, the plasma is less reflective due to the presence of both an hF field and the effect of relativistic electrons. On the other hand, for a low-frequency incident wave the reflection coefficient is directly proportional to the amplitude of the hF field. Also, it is shown that the relativistic electron plasma leads to a decrease in the value of reflection coefficient in comparison with the case of the non relativistic plasma.

关键词： electrostatic wave relativistic plasma waveguide reflection coefficient separation method

Neutralizing antibodies in hepatitis C virus infection

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World Journal of Gastroenterology 2007年第36期13卷 4824-4830页

作者： Mirjam B Zeisel Samira Fafi-Kremer isabel Fofana heidi barth Franoise Stoll-Keller Michel Doffo■l Thomas F Baumert Inserm U748Strasbourg France Université Louis Pasteur Strasbourg France Liver Diseases Branch National Institute of Diabetes and Digestive and Kidney Diseases National Institutesof Health Bethesda MD United States Universitaires de Strasbourg Strasbourg France Service d'hépatogastro-entérologie Hpitaux Universitaires de Strasbourg

hepatitis C virus (hCV) is a major cause of hepatitis world-wide. The majority of infected individuals develop chronic hepatitis which can then progress to liver cirrhosis and hepatocellular carcinoma. Spontaneous viral clearance occurs in about 20%-30% of acutely infected individuals and results in resolution of infection without sequaelae. Both viral and host factors appear to play an important role for resolution of acute infection. A large body of evidence suggests that a strong, multispecific and long-lasting cellular immune response appears to be important for control of viral infection in acute hepatitis C. Due too the lack of convenient neutralization assays, the impact of neutralizing responses for control of viral infection had been less defined. In recent years, the development of robust tissue culture model systems for hCV entry and infection has finally allowed study of antibody-mediated neutralization and to gain further insights into viral targets of host neutralizing responses. In addition, detailed analysis of antibody-mediated neutralization in individual patients as well as cohorts with well defined viral isolates has enabled the study of neutralizing responses in the course of hCV infection and characterization of the impact of neutralizing antibodiesfor control of viral infection. This review will summarize recent progress in the understanding of the molecular mechanisms of antibody-mediated neutralization and its impact for hCV pathogenesis.

关键词： hepatitis C virus Virus-host cell interaction Viral entry Neutralizing antibodies

The evolutionary development of plant-feeding insects and their nutritional endosymbionts

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Insect Science 2017年第6期24卷 910-928页

作者： isabel h. Skidmore Allison K. hansen Department of Entomology University of Illinois Urbana-Champaign Ilfinois USA

herbivorous insects have evolved diverse mechanisms enabling them to feed on plants with suboptimal nutrient availability. Low nutrient availability negatively impacts insect herbivore development and fitness. To overcome this obstacle numerous insect lineages have evolved intimate associations with nutritional endosymbionts. This is especially true for insects that specialize on nitrogen-poor substrates, as these insects are highly dependent on intraceUular symbionts to provide nitrogen lacking in their insect host＇s diet. Emerging evidence in these systems suggest that the symbiont＇s and/or the insect＇s biosynthetic pathways are dynamically regulated throughout the insect＇s development to potentially cope with the insect＇s changing nutritional demands. In this review, we evaluate the evolutionary development of symbiotic insect cells （bacteriocytes） by comparing and contrasting genes and mechanisms involved in maintaining and regulating the nutritional symbiosis throughout insect development in a diversity of insect herbivore-endosymbiont associations. With new advances in genome sequencing and functional genomics, we eval- uate to what extent nutritional symbioses are shaped by （i） the regulation of symbiont titer, （ii） the regulation of insect symbiosis genes, and （iii） the regulation of symbiont genes. We discuss how important these mechanisms are for the biosynthesis of essential amino acids and vitamins across insect life stages in divergent insect-symbiont systems. We conclude by suggesting future directions of research to further elucidate the evolutionary development of bacteriocytes and the impact of these nutritional symbioses on insect plant interactions.

关键词： development evolutionary insect herbivores plant-insect microbe interactions symbiosis

Primary carbohydrate metabolism genes participate in heat-stress memory at the shoot apical meristem of Arabidopsis thaliana

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Molecular Plant 2024年第4期17卷 676-676页

作者： Justyna Jadwiga Olas Federico Apelt Maria Grazia Annunziata Sheeba John Sarah isabel Richard Saurabh Gupta Friedrich Kragler Salma Balazadeh Bernd Mueller-Roeber 不详

(Molecular Plant 14,1508-1524,September 62021)After the original publication of the above article,attentive readers identified errors in Figure 4h that needed correction as *** 4h contained the erroneous labels“10 DAP(7 DAT),”which should have each read,“7 DAP(4 DAT).”To avoid any confusion and ensure consistency across our figures,we modified some of the Col-0 images in a corrected version of Figure 4h below to resemble the exact same Col-0 images as in Figure *** details of the changes are as follows:rotation(Col-0 Primed,all timepoints;Col-0 Triggered,3 DAP and 5 DAP;Col-0 Primed/triggered,3 DAP and 5 DAP),replacement(Col-0 Triggered,7 DAP),and different cropping(Col-0 Primed/triggered,7 DAP).

关键词： Figure metabolism Prime

CuPc based organic-inorganic hetero-junction with Au electrodes

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Journal of Semiconductors 2010年第7期31卷 22-25页

作者： Zubair Ahmad Muhammad h.Sayyad kh.S.Karimov Ghulam Ishaq khan Institute of Engineering Sciences and Technology TopiNWFP23460Pakistan Department of Mechanical Engineering 20 Symond Street AucklandUniversity of AucklandNew Zealand

A hetero-junction of n-silicon（n-Si） and copper phthalocyanine（CuPc） has been *** current -voltage characteristics were investigated to explain the rectification and conduction *** effect of temperature and humidity on the electrical properties of n-Si/CuPc hetero-junction has also been *** characteristics of the junction have been observed to be temperature and humidity dependent,so it is suggested that this junction can be used as a temperature and humidity sensor.

关键词： inorganic-organic hetero-junction n-Si CuPc

Electrical characterization of the organic semiconductor Ag/CuPc/Au Schottky diode

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Journal of Semiconductors 2011年第4期32卷 52-56页

作者： Mutabar Shah M.h.Sayyad kh.S.Karimov Ghulam Ishaq khan Institute of Engineering Sciences and Technology physical Technical Institute of Academy of Sciences

This paper reports on the fabrication and investigation of a surface-type organic semiconductor copper phthalocyanine（CuPc） based diode.A thin film of CuPc of thickness 100 nm was thermally sublimed onto a glass substrate with preliminary deposited metallic electrodes to form a surface-type Ag/CuPc/Au Schottky *** current-voltage characteristics were measured at room temperature under dark *** barrier height was calculated as 1.05 *** values of mobility and conductivity was found to be 1.74×10;cm;/（V·s） and 5.5×10;Ω;·cm;,*** low voltages the device showed ohmic conduction and the space charge limited current conduction mechanisms were dominated at higher voltages.

关键词： Schottky diode copper phthalocyanine thin film organic semiconductor mobility

Oxidized organic molecules in the tropical free troposphere over Amazonia

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National Science Review 2024年第1期11卷 174-184页

作者： Qiaozhi Zha Diego Aliaga Radovan Krejci Victoria A.Sinclair Cheng Wu Giancarlo Ciarelli Wiebke Scholz Liine heikkinen Eva Partoll Yvette Gramlich Wei huang Markus Leiminger Joonas Enroth Otso Per?kyl? Runlong Cai Xuemeng Chen Alkuin Maximilian Koenig Fernando Velarde isabel Moreno Tuukka Pet?j? Paulo Artaxo Paolo Laj Armin hansel Samara Carbone Markku Kulmala Marcos Andrade Douglas Worsnop Claudia Mohr Federico Bianchi Institute for Atmospheric and Earth System Research/Physics University of Helsinki Joint International Research Laboratory of Atmospheric and Earth System Sciences Nanjing University Department of Environmental Science & Bolin Centre for Climate Research Stockholm University Department of Chemistry and Molecular Biology University of Gothenburg Institute for Ion and Applied Physics University of Innsbruck Ionicon Analytik Gmbh Laboratory for Atmospheric Physics Institute for Physics Research Universidad Mayor de San Andrés Institute of Physics University of Sao Paulo Institute for Geosciences and Environmental Research (IGE) University of Grenoble Alpes Agrarian Sciences Institute Federal University of Uberl?ndia Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology Department of Atmospheric and Oceanic Sciences University of Maryland Aerodyne Research Inc. Department of Environmental System Science ETH Zürich Switzerland and Laboratory of Atmospheric Chemistry Paul Scherrer Institute

New particle formation(NPF) in the tropical free troposphere(FT) is a globally important source of cloud condensation nuclei, affecting cloud properties and climate. Oxidized organic molecules(OOMs)produced from biogenic volatile organic compounds are believed to contribute to aerosol formation in the tropical FT, but without direct chemical observations. We performed in situ molecular-level OOMs measurements at the Bolivian station Chacaltaya at 5240 m above sea level, on the western edge of Amazonia. For the first time, we demonstrate the presence of OOMs, mainly with 4–5 carbon atoms, in both gas-phase and particle-phase(in terms of mass contribution) measurements in tropical FT air from Amazonia. These observations, combined with air mass history analyses, indicate that the observed OOMs are linked to isoprene emitted from the rainforests hundreds of kilometers away. Based on particle-phase measurements, we find that these compounds can contribute to NPF, at least the growth of newly formed nanoparticles, in the tropical FT on a continental scale. Thus, our study is a fundamental and significant step in understanding the aerosol formation process in the tropical FT.

关键词： oxidized organic molecules tropical aerosol formation Amazon free troposphere