ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Publication Date: 2016-07-21
    Description: Sea spray aerosol particles are an integral part of the Earth's radiation budget. To date, the inorganic composition of nascent sea spray aerosol particles have widely been assumed to be equivalent to the inorganic composition of seawater. Here we challenge this assumption using a laboratory sea spray chamber containing both natural and artificial seawater, as well as with ambient aerosol samples collected over the central Arctic Ocean during summer. We observe significant enrichment of calcium in submicrometer (〈1 μ m in diameter) sea spray aerosol particles when particles are generated from both seawater sources in the laboratory as well as in the ambient aerosols samples. We also observe a tendency for increasing calcium enrichment with decreasing particle size. Our results suggest that calcium enrichment in sea spray aerosol particles may be environmentally significant with implications for our understanding of sea spray aerosol, its impact on Earth's climate, as well as the chemistry of the marine atmosphere.
    Print ISSN: 0094-8276
    Electronic ISSN: 1944-8007
    Topics: Geosciences , Physics
    Published by Wiley on behalf of American Geophysical Union (AGU).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2015-12-29
    Description: The creation of a semi insulating (SI) buffer layer in AlGaN/GaN High Electron Mobility Transistor (HEMT) devices is crucial for preventing a current path beneath the two-dimensional electron gas (2DEG). In this investigation, we evaluate the use of a gaseous carbon gas precursor, propane, for creating a SI GaN buffer layer in a HEMT structure. The carbon doped profile, using propane gas, is a two stepped profile with a high carbon doping (1.5 × 10 18  cm −3 ) epitaxial layer closest to the substrate and a lower doped layer (3 × 10 16  cm −3 ) closest to the 2DEG channel. Secondary Ion Mass Spectrometry measurement shows a uniform incorporation versus depth, and no memory effect from carbon doping can be seen. The high carbon doping (1.5 × 10 18  cm −3 ) does not influence the surface morphology, and a roughness root-mean-square value of 0.43 nm is obtained from Atomic Force Microscopy. High resolution X-ray diffraction measurements show very sharp peaks and no structural degradation can be seen related to the heavy carbon doped layer. HEMTs are fabricated and show an extremely low drain induced barrier lowering value of 0.1 mV/V, demonstrating an excellent buffer isolation. The carbon doped GaN buffer layer using propane gas is compared to samples using carbon from the trimethylgallium molecule, showing equally low leakage currents, demonstrating the capability of growing highly resistive buffer layers using a gaseous carbon source.
    Print ISSN: 0003-6951
    Electronic ISSN: 1077-3118
    Topics: Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2011-05-18
    Description: Development in plants is controlled by abiotic environmental cues such as day length, light quality, temperature, drought, and salinity. These signals are sensed by a variety of systems and transmitted by different signal transduction pathways. Ultimately, these pathways are integrated to control expression of specific target genes, which encode proteins that regulate development and differentiation. The molecular mechanisms for such integration have remained elusive. We here show that a linear 130-amino-acids-long sequence in the Med25 subunit of the Arabidopsis thaliana Mediator is a common target for the drought response element binding protein 2A, zinc finger homeodomain 1, and Myb-like transcription factors which are involved in different stress response pathways. In addition, our results show that Med25 together with drought response element binding protein 2A also function in repression of PhyB-mediated light signaling and thus integrate signals from different regulatory pathways.
    Print ISSN: 0027-8424
    Electronic ISSN: 1091-6490
    Topics: Biology , Medicine , Natural Sciences in General
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2014-08-27
    Description: This study presents analysis of the residual strain and related surface morphology of high-Al-content Al 0.82 Ga 0.18 N layers doped by silicon up to the level of 3 × 10 19  cm −3 . We focus on understanding the basic mechanisms which underlie the formation of the distinct surface morphology of the Al 0.82 Ga 0.18 N:Si layers and their conductivity. We discuss the development of certain facet structure (nanopipes) within the doped layers, which is apparent at the high Si doping levels. The formation of nanopipes influences the conductivity of the layers. It is anticipated to give rise to facets with SiN-related coverage, outcompeting the incorporation of Si at substitutional donor sites in the lattice. We do not find evidence for kinetic stabilization of preferential crystallographic facets when a dopant flow of bis(cyclopentadienyl)magnesium (Cp 2 Mg), instead of silane (SiH 4 ), is implemented in the doping process.
    Print ISSN: 0003-6951
    Electronic ISSN: 1077-3118
    Topics: Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2014-07-17
    Description: Breaking waves on the ocean surface produce bubbles which, upon bursting, deliver seawater constituents into the atmosphere as sea spray aerosol particles. One way of investigating this process in the laboratory is to generate a bubble plume by a continuous plunging jet. We performed a series of laboratory experiments to elucidate the role of seawater temperature on aerosol production from artificial seawater free from organic contamination using a plunging jet. The seawater temperature was varied from −1.3 °C to 30.1 °C while the volume of air entrained by the jet, surface bubble size distributions, and size distribution of the aerosol particles produced were monitored. We observed that the volume of air entrained decreased as the seawater temperature was increased. The number of surface bubbles with film radius smaller than 2 mm decreased nonlinearly with seawater temperature. This decrease was coincident with a substantial reduction in particle production.The number concentrations of particles with dry diameter less than ~1  μ m decreased substantially as the seawater temperature was increased from −1.3 °C to ~9 °C. With further increase in seawater temperature (up to 30 °C) a small increase in the number concentration of larger particles (dry diameter 〉~0.3  μ m) was observed. Based on these observations, we infer that as seawater temperature increases, the process of bubble fragmentation changes, resulting in decreased air entrainment by the plunging jet, as well as the number of bubbles with film radius smaller than 2 mm. This again results in decreased particle production with increasing seawater temperature.
    Print ISSN: 0148-0227
    Topics: Geosciences , Physics
    Published by Wiley on behalf of American Geophysical Union (AGU).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2003-06-14
    Description: We modeled how the charged levels of different transfer RNAs (tRNAs) that carry the same amino acid (isoacceptors) respond when this amino acid becomes growth-limiting. The charged levels will approach zero for some isoacceptors (such as tRNA2Leu) and remain high for others (such as tRNA4Leu), as determined by the concentrations of isoacceptors and how often their codons occur in protein synthesis. The theory accounts for (synonymous) codons for the same amino acid that are used in ribosome-mediated transcriptional attenuation, the choices of synonymous codons in trans-translating transfermessenger RNA, and the overrepresentation of rare codons in messenger RNAs for amino acid biosynthetic enzymes.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Elf, Johan -- Nilsson, Daniel -- Tenson, Tanel -- Ehrenberg, Mans -- New York, N.Y. -- Science. 2003 Jun 13;300(5626):1718-22.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Cell and Molecular Biology, Uppsala University, Biomedical Center, Box 596, 751 24 Uppsala, Sweden.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/12805541" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acids/*metabolism ; Amino Acyl-tRNA Synthetases/metabolism ; *Codon ; Escherichia coli/*genetics/growth & development/metabolism ; Escherichia coli Proteins/biosynthesis/genetics ; Frameshifting, Ribosomal ; Gene Expression Regulation, Bacterial ; Kinetics ; Mathematics ; Models, Genetic ; Operon ; *Protein Biosynthesis ; Pyrophosphatases/genetics/metabolism ; RNA, Bacterial/genetics/metabolism ; RNA, Messenger/genetics/metabolism ; RNA, Transfer/genetics/metabolism ; RNA, Transfer, Amino Acyl/genetics/*metabolism ; Ribosomes/metabolism
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2005-07-16
    Description: Whole-genome sequencing of the protozoan pathogen Trypanosoma cruzi revealed that the diploid genome contains a predicted 22,570 proteins encoded by genes, of which 12,570 represent allelic pairs. Over 50% of the genome consists of repeated sequences, such as retrotransposons and genes for large families of surface molecules, which include trans-sialidases, mucins, gp63s, and a large novel family (〉1300 copies) of mucin-associated surface protein (MASP) genes. Analyses of the T. cruzi, T. brucei, and Leishmania major (Tritryp) genomes imply differences from other eukaryotes in DNA repair and initiation of replication and reflect their unusual mitochondrial DNA. Although the Tritryp lack several classes of signaling molecules, their kinomes contain a large and diverse set of protein kinases and phosphatases; their size and diversity imply previously unknown interactions and regulatory processes, which may be targets for intervention.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉El-Sayed, Najib M -- Myler, Peter J -- Bartholomeu, Daniella C -- Nilsson, Daniel -- Aggarwal, Gautam -- Tran, Anh-Nhi -- Ghedin, Elodie -- Worthey, Elizabeth A -- Delcher, Arthur L -- Blandin, Gaelle -- Westenberger, Scott J -- Caler, Elisabet -- Cerqueira, Gustavo C -- Branche, Carole -- Haas, Brian -- Anupama, Atashi -- Arner, Erik -- Aslund, Lena -- Attipoe, Philip -- Bontempi, Esteban -- Bringaud, Frederic -- Burton, Peter -- Cadag, Eithon -- Campbell, David A -- Carrington, Mark -- Crabtree, Jonathan -- Darban, Hamid -- da Silveira, Jose Franco -- de Jong, Pieter -- Edwards, Kimberly -- Englund, Paul T -- Fazelina, Gholam -- Feldblyum, Tamara -- Ferella, Marcela -- Frasch, Alberto Carlos -- Gull, Keith -- Horn, David -- Hou, Lihua -- Huang, Yiting -- Kindlund, Ellen -- Klingbeil, Michele -- Kluge, Sindy -- Koo, Hean -- Lacerda, Daniela -- Levin, Mariano J -- Lorenzi, Hernan -- Louie, Tin -- Machado, Carlos Renato -- McCulloch, Richard -- McKenna, Alan -- Mizuno, Yumi -- Mottram, Jeremy C -- Nelson, Siri -- Ochaya, Stephen -- Osoegawa, Kazutoyo -- Pai, Grace -- Parsons, Marilyn -- Pentony, Martin -- Pettersson, Ulf -- Pop, Mihai -- Ramirez, Jose Luis -- Rinta, Joel -- Robertson, Laura -- Salzberg, Steven L -- Sanchez, Daniel O -- Seyler, Amber -- Sharma, Reuben -- Shetty, Jyoti -- Simpson, Anjana J -- Sisk, Ellen -- Tammi, Martti T -- Tarleton, Rick -- Teixeira, Santuza -- Van Aken, Susan -- Vogt, Christy -- Ward, Pauline N -- Wickstead, Bill -- Wortman, Jennifer -- White, Owen -- Fraser, Claire M -- Stuart, Kenneth D -- Andersson, Bjorn -- AI045039/AI/NIAID NIH HHS/ -- AI45038/AI/NIAID NIH HHS/ -- AI45061/AI/NIAID NIH HHS/ -- R01 AI031077/AI/NIAID NIH HHS/ -- R01 AI031077-11/AI/NIAID NIH HHS/ -- U01 AI045038/AI/NIAID NIH HHS/ -- U01 AI045039/AI/NIAID NIH HHS/ -- Wellcome Trust/United Kingdom -- New York, N.Y. -- Science. 2005 Jul 15;309(5733):409-15.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Parasite Genomics, Institute for Genomic Research, Rockville, MD 20850, USA. nelsayed@tigr.org〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16020725" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Chagas Disease/drug therapy/parasitology ; DNA Repair ; DNA Replication ; DNA, Mitochondrial/genetics ; DNA, Protozoan/genetics ; Genes, Protozoan ; *Genome, Protozoan ; Humans ; Meiosis ; Membrane Proteins/chemistry/genetics/physiology ; Multigene Family ; Protozoan Proteins/chemistry/*genetics/physiology ; Recombination, Genetic ; Repetitive Sequences, Nucleic Acid ; Retroelements ; *Sequence Analysis, DNA ; Signal Transduction ; Telomere/genetics ; Trypanocidal Agents/pharmacology/therapeutic use ; Trypanosoma cruzi/chemistry/*genetics/physiology
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2005-07-16
    Description: A comparison of gene content and genome architecture of Trypanosoma brucei, Trypanosoma cruzi, and Leishmania major, three related pathogens with different life cycles and disease pathology, revealed a conserved core proteome of about 6200 genes in large syntenic polycistronic gene clusters. Many species-specific genes, especially large surface antigen families, occur at nonsyntenic chromosome-internal and subtelomeric regions. Retroelements, structural RNAs, and gene family expansion are often associated with syntenic discontinuities that-along with gene divergence, acquisition and loss, and rearrangement within the syntenic regions-have shaped the genomes of each parasite. Contrary to recent reports, our analyses reveal no evidence that these species are descended from an ancestor that contained a photosynthetic endosymbiont.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉El-Sayed, Najib M -- Myler, Peter J -- Blandin, Gaelle -- Berriman, Matthew -- Crabtree, Jonathan -- Aggarwal, Gautam -- Caler, Elisabet -- Renauld, Hubert -- Worthey, Elizabeth A -- Hertz-Fowler, Christiane -- Ghedin, Elodie -- Peacock, Christopher -- Bartholomeu, Daniella C -- Haas, Brian J -- Tran, Anh-Nhi -- Wortman, Jennifer R -- Alsmark, U Cecilia M -- Angiuoli, Samuel -- Anupama, Atashi -- Badger, Jonathan -- Bringaud, Frederic -- Cadag, Eithon -- Carlton, Jane M -- Cerqueira, Gustavo C -- Creasy, Todd -- Delcher, Arthur L -- Djikeng, Appolinaire -- Embley, T Martin -- Hauser, Christopher -- Ivens, Alasdair C -- Kummerfeld, Sarah K -- Pereira-Leal, Jose B -- Nilsson, Daniel -- Peterson, Jeremy -- Salzberg, Steven L -- Shallom, Joshua -- Silva, Joana C -- Sundaram, Jaideep -- Westenberger, Scott -- White, Owen -- Melville, Sara E -- Donelson, John E -- Andersson, Bjorn -- Stuart, Kenneth D -- Hall, Neil -- AI045039/AI/NIAID NIH HHS/ -- AI45038/AI/NIAID NIH HHS/ -- AI45061/AI/NIAID NIH HHS/ -- R01 AI043062/AI/NIAID NIH HHS/ -- U01 AI040599/AI/NIAID NIH HHS/ -- U01 AI043062/AI/NIAID NIH HHS/ -- U01 AI045038/AI/NIAID NIH HHS/ -- U01 AI045039/AI/NIAID NIH HHS/ -- Wellcome Trust/United Kingdom -- New York, N.Y. -- Science. 2005 Jul 15;309(5733):404-9.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Institute for Genomic Research, 9712 Medical Center Drive, Rockville, MD 20850, USA. nelsayed@tigr.org〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16020724" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Biological Evolution ; Chromosomes/genetics ; Evolution, Molecular ; Gene Transfer, Horizontal ; Genes, Protozoan ; *Genome, Protozoan ; Genomics ; Leishmania major/chemistry/*genetics/metabolism ; Molecular Sequence Data ; Multigene Family ; Mutation ; Phylogeny ; Plastids/genetics ; *Proteome ; Protozoan Proteins/chemistry/*genetics/physiology ; Recombination, Genetic ; Retroelements ; Species Specificity ; Symbiosis ; Synteny ; Telomere/genetics ; Trypanosoma brucei brucei/chemistry/*genetics/metabolism ; Trypanosoma cruzi/chemistry/*genetics/metabolism
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2013-01-04
    Description: [1]  Global climate model output is combined with an emission parameterization to estimate the change in the global and regional sea salt aerosol number emission from 1870 to 2100. Global average results suggest a general increase in sea salt aerosol number emission due to increasing surface wind speed. However, the emission changes are not uniform over the aerosol size spectrum due to an increase in sea surface temperature. From 1870 to 2100 the emission of coarse mode particles (dry diameter D p  〉 655 nm) increase by approximately 10 % (global average), whereas no significant change in the emission of ultrafine mode aerosols (dry diameter D p  〈 76 nm) was found over the same period. Significant regional differences in the number emission trends were also found. Based on CAM-Oslo global climate model output, no straight-forward relationship was found between the change in the number emissions and changes in the sea salt aerosol burden or optical thickness. This is attributed to a change in the simulated residence time of the sea salt aerosol. For the 21st century, a decrease in the residence time leads to a weaker sea salt aerosol-climate feedback that what would be inferred based on changes in number emissions alone. Finally, quantifying any potential impact on marine stratocumulus cloud microphysical and radiative properties due to changes in sea salt aerosol number emissions is likely to be complicated by commensurate changes in anthropogenic aerosol emissions and changes in meteorology.
    Print ISSN: 0148-0227
    Topics: Geosciences , Physics
    Published by Wiley on behalf of American Geophysical Union (AGU).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 1984-01-01
    Print ISSN: 0149-1423
    Electronic ISSN: 1943-2674
    Topics: Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...