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The Solution Structure Of The N-Terminal Domain Of Human Vitronectin: Proximal Sites That Regulate Fibrinolysis And Cell Migration, Anand Mayasundari, Neil A. Whittemore, Engin H. Serpersu, Cynthia B. Peterson Jul 2004

The Solution Structure Of The N-Terminal Domain Of Human Vitronectin: Proximal Sites That Regulate Fibrinolysis And Cell Migration, Anand Mayasundari, Neil A. Whittemore, Engin H. Serpersu, Cynthia B. Peterson

Faculty Publications

The three-dimensional structure of an N-terminal fragment comprising the first 51 amino acids from human plasma vitronectin, the somatomedin B (SMB) domain, has been determined by two-dimensional NMR approaches. An average structure was calculated, representing the overall fold from a set of 20 minimized structures. The core residues (18-41) overlay with a root mean square deviation of 2.29 ± 0.62 Å. The N- and C-terminal segments exhibit higher root mean square deviations, reflecting more flexibility in solution and/or fewer long-range NOEs for these regions. Residues 26-30 form a unique single-turn α-helix, the locus where plasminogen activator inhibitor type-1 (PAI-1) is …

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Constraints On Adaptive Evolution: The Functional Trade-Off Between Reproduction And Fast-Start Swimming Performance In The Trinidadian Guppy (Poecilia Reticulata), Cameron K. Ghalambor, David N. Reznick, Jeffrey A. Walker Phd Jul 2004

Constraints On Adaptive Evolution: The Functional Trade-Off Between Reproduction And Fast-Start Swimming Performance In The Trinidadian Guppy (Poecilia Reticulata), Cameron K. Ghalambor, David N. Reznick, Jeffrey A. Walker Phd

Faculty Publications

The empirical study of natural selection reveals that adaptations often involve trade-offs between competing functions. Because natural selection acts on whole organisms rather than isolated traits, adaptive evolution may be constrained by the interaction between traits that are functionally integrated. Yet, few attempts have been made to characterize how and when such constraints are manifested or whether they limit the adaptive divergence of populations. Here we examine the consequences of adaptive life-history evolution on locomotor performance in the live-bearing guppy. In response to increased predation from piscivorous fish, Trinidadian guppies evolve an increased allocation of resources toward reproduction. These populations …

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A Patch Hath Smaller Patches: Delineating Ecological Neighborhoods For Parasites, Derek Zelmer, John R. Seed Jul 2004

A Patch Hath Smaller Patches: Delineating Ecological Neighborhoods For Parasites, Derek Zelmer, John R. Seed

Faculty Publications

Use of the host individual as a boundary for parasite populations and communities provides an unambiguous spatial unit that is useful for pattern description, but this framework precludes consideration of the host landscape and within-host population dynamics. Recognizing host individuals as spatially and temporally complex landscapes requires modified concepts of parasite populations and communities. An outline of the currently accepted hierarchies of parasite populations and communities is provided on the basis of ecological neighborhoods that are delineated by discrete habitat patches or functional dynamics (or both), as opposed to host individuals. This parasite-based framework accommodates consideration of both within- and …

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Molecular Analysis Of Carbon Monoxide-Oxidizing Bacteria Associated With Recent Hawaiian Volcanic Deposits, Kari E. Dunfield, Gary M. King Jul 2004

Molecular Analysis Of Carbon Monoxide-Oxidizing Bacteria Associated With Recent Hawaiian Volcanic Deposits, Kari E. Dunfield, Gary M. King

Faculty Publications

Genomic DNA extracts from four sites at Kilauea Volcano were used as templates for PCR amplification of the large subunit (coxL) of aerobic carbon monoxide dehydrogenase. The sites included a 42-year-old tephra deposit, a 108-year-old lava flow, a 212-year-old partially vegetated ash-and-tephra deposit, and an approximately 300-year-old forest. PCR primers amplified coxL sequences from the OMP clade of CO oxidizers, which includes isolates such as Oligotropha carboxidovorans, Mycobacterium tuberculosis, and Pseudomonas thermocarboxydovorans. PCR products were used to create clone libraries that provide the first insights into the diversity and phylogenetic affiliations of CO oxidizers in situ. On the basis of …

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Initial Studies On Sperm Cryopreservation Of A Live-Bearing Fish, The Green Swordtail Xiphophorus Helleri, Changjiang Huang, Qiaoxiang Dong, Ronald B. Walter, Terrence R. Tiersch Jul 2004

Initial Studies On Sperm Cryopreservation Of A Live-Bearing Fish, The Green Swordtail Xiphophorus Helleri, Changjiang Huang, Qiaoxiang Dong, Ronald B. Walter, Terrence R. Tiersch

Faculty Publications

Swordtails and platyfish of the genus Xiphophorus are valuable models for biomedical research and are also commercially raised as ornamental fish valued by aquarists. While research use and commercial interest increases yearly in these fish, cryopreservation of sperm is unexplored in this genus. Xiphophorus are live-bearing fishes characterized by small body sizes, limited sperm volumes, and internal fertilization, an atypical reproductive mode for fish. These attributes make research involving cryopreservation of Xiphophorus germplasm challenging. To explore methods for sperm cryopreservation, this study evaluated the effect of different loading volumes of sperm suspension in 0.25-ml French straws, different dilution ratios of …

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Politics Of Embryonic Discourse, Kevin Quinn Jul 2004

Politics Of Embryonic Discourse, Kevin Quinn

Faculty Publications

In our brave new world of stem cells, clones, and parthenotes, how should we talk about early human embryos? In fashioning a response to this very thorny question, Ann Kiessling has a core message. It is: (1)that new science produces "new" conceptuses;(2) that science and scientists have failed to differentiate (with appropriate clarity) these new ex vivo conceptuses from those createdin vivo; (3) that new, more appropriate and scientifically-informed, terms are necessary; and (4) that this new language should transform the public discourse about human embryos. No one would deny that the subtleties of human embryology are neglected in public …

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Automatic Detection And Validity Of The Sea-Ice Edge: An Application Of Enhanced-Resolution Quikscat/Seawinds Data, David G. Long, Jorg Haarpaintner, Rasmus T. Tonboe, Michael L. Van Woert Jul 2004

Automatic Detection And Validity Of The Sea-Ice Edge: An Application Of Enhanced-Resolution Quikscat/Seawinds Data, David G. Long, Jorg Haarpaintner, Rasmus T. Tonboe, Michael L. Van Woert

Faculty Publications

Sea-ice edge detection is an essential task at the different national ice services to secure navigation in ice-covered seas. Comparison between the Remund and Long ice mask image from enhanced-resolution QuikScat/SeaWinds (QS) products and the analyzed ice edge from high-resolution RADARSAT synthetic aperture radar has shown that the automatically determined QS ice mask underestimates the Arctic ice extent. QS data was statistically analyzed by colocating the data with ice charts around Greenland and with the National Aeronautics and Space Administration Team's Special Sensor Microwave/Imager (SSM/I) ice concentration algorithm over the whole Arctic region. All variables, i.e., the backscatter in vertical …

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Allosteric Β1 Integrin Antibodies That Stabilize The Low Affinity State By Preventing The Swing-Out Of The Hybrid Domain, Bing Hao Luo, Konstantin Strokovich, Thomas Walz, Timothy A. Springer, Junichi Takagi Jun 2004

Allosteric Β1 Integrin Antibodies That Stabilize The Low Affinity State By Preventing The Swing-Out Of The Hybrid Domain, Bing Hao Luo, Konstantin Strokovich, Thomas Walz, Timothy A. Springer, Junichi Takagi

Faculty Publications

The ligand binding function of integrins can be modulated by various monoclonal antibodies by both direct and indirect mechanisms. We have characterized an anti-β1 antibody, SG/19, that had been reported to inhibit the function of the β1 integrin on the cell surface. SG/19 recognized the wild type β1 subunit that exists in a conformational equilibrium between the high and low affinity states but bound poorly to a mutant β1 integrin that had been locked in a high affinity state. Epitope mapping of SG/19 revealed that Thr82 in the β1 subunit, located at the outer face of the boundary between the …

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Exceptional Record Of Mid-Pleistocene Vertebrates Helps Differentiate Climatic From Anthropogenic Ecosystem Perturbations, Anthony D. Barnosky, Christopher J. Bell, Steven D, Emslie, H. Thomas Goodwin, Jim I. Mead, Charles A. Repenning, Eric Scott, Alan B. Shabel Jun 2004

Exceptional Record Of Mid-Pleistocene Vertebrates Helps Differentiate Climatic From Anthropogenic Ecosystem Perturbations, Anthony D. Barnosky, Christopher J. Bell, Steven D, Emslie, H. Thomas Goodwin, Jim I. Mead, Charles A. Repenning, Eric Scott, Alan B. Shabel

Faculty Publications

Mid-Pleistocene vertebrates in North America are scarce but important for recognizing the ecological effects of climatic change in the absence of humans. We report on a uniquely rich mid-Pleistocene vertebrate sequence from Porcupine Cave, Colorado, which records at least 127 species and the earliest appearances of 30 mammals and birds. By analyzing >20,000 mammal fossils in relation to modern species and independent climatic proxies, we determined how mammal communities reacted to presumed glacial-interglacial transitions between 1,000,000 and 600,000 years ago. We conclude that climatic warming primarily affected mammals of lower trophic and size categories, in contrast to documented human impacts …

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Description And Assessment Of A Business Plan Competition And New Venture Fair At San José State University, Malu Roldan, Asbjorn Osland, Michael Solt, Burton Dean Jun 2004

Description And Assessment Of A Business Plan Competition And New Venture Fair At San José State University, Malu Roldan, Asbjorn Osland, Michael Solt, Burton Dean

Faculty Publications

After the first business plan competition, in May 2003, San José State University (SJSU) faculty and community entrepreneurs serving on the university’s Silicon Valley Center for Entrepreneurship (SVCE) concluded that the process should be spread over an academic year. Hence, the New Venture Fair (NVF) was born, which was held Dec. 16, 2003. The feedback from all sources has been very positive regarding the NVF. A significant NVF exhibit was the Hewlett Packard Mobile Computing Grant (HPMCG). All teams completed projects that were impressive to most observers from the university and greater community but additional lessons were learned that will …

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Proteomic Analysis Of Arabidopsis Glutathione S-Transferases From Benoxacor- And Copper-Treated Seedlings, Aaron P. Smith, Ben P. Deridder, Woei Jiun Guo, Erin H. Seeley, Fred E. Regnier, Peter B. Goldsbrough Jun 2004

Proteomic Analysis Of Arabidopsis Glutathione S-Transferases From Benoxacor- And Copper-Treated Seedlings, Aaron P. Smith, Ben P. Deridder, Woei Jiun Guo, Erin H. Seeley, Fred E. Regnier, Peter B. Goldsbrough

Faculty Publications

Glutathione S-transferases (GSTs) are involved in many stress responses in plants, for example, participating in the detoxification of xenobiotics and limiting oxidative damage. Studies examining the regulation of this gene family in diverse plant species have focused primarily on RNA expression. A proteomics method was developed to identify GSTs expressed in Arabidopsis seedlings and to determine how the abundance of these proteins changed in response to copper, a promoter of oxidative stress, and benoxacor, a herbicide safener. Eight GSTs were identified in seedlings grown under control conditions, and only one, AtGSTU19, was induced by benoxacor. In contrast, four GSTs, AtGSTF2, …

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A Physiochemically Constrained Seawater Culturing System For Production Of Benthic Foraminifera, Christopher J. Hintz, G. Thomas Chandler, Jay M. Bernhardt, Daniel C. Mccorkle, Suzanne M. Havach, Jessica K. Blanks, Timothy J. Shaw Jun 2004

A Physiochemically Constrained Seawater Culturing System For Production Of Benthic Foraminifera, Christopher J. Hintz, G. Thomas Chandler, Jay M. Bernhardt, Daniel C. Mccorkle, Suzanne M. Havach, Jessica K. Blanks, Timothy J. Shaw

Faculty Publications

No abstract provided.

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Universal Primers For The Amplification Of Chloroplast Microsatellites In Grasses (Poaceae), Jim Provan, Pamela M. Biss, Darragh Mcmeel, Sarah Mathews Jun 2004

Universal Primers For The Amplification Of Chloroplast Microsatellites In Grasses (Poaceae), Jim Provan, Pamela M. Biss, Darragh Mcmeel, Sarah Mathews

Faculty Publications

Attempts to design truly universal primers to amplify chloroplast microsatellites have met with limited success due to nonconservation of repeat loci across widely divergent taxa. We have used the complete chloroplast genome sequences of rice, maize and wheat to design five pairs of primers that amplify homologous mononucleotide repeats across the Poaceae (grasses). Sequencing confirmed conservation of repeat motifs across subfamilies and a preliminary study in Anthoxanthum odoratum revealed polymorphism at two loci with a haplotype diversity value of 0.495. These primers provide a valuable tool to study cytoplasmic diversity in this extensively studied and economically important range of taxa.

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Kaposi's Sarcoma-Associated Herpesvirus Glycoprotein K8.1 Is Dispensable For Virus Entry, Rafael E. Luna, Fuchun Zhou, Abolgashem Baghian, Vladimir Chouljenko, Bagher Forghani, Shou Jiang Gao, Konstantin G. Kousoulas Jun 2004

Kaposi's Sarcoma-Associated Herpesvirus Glycoprotein K8.1 Is Dispensable For Virus Entry, Rafael E. Luna, Fuchun Zhou, Abolgashem Baghian, Vladimir Chouljenko, Bagher Forghani, Shou Jiang Gao, Konstantin G. Kousoulas

Faculty Publications

Kaposi's sarcoma-associated herpesvirus (KSHV) is considered the etiologic agent of Kaposi's sarcoma and several lymphoproliferative disorders. Recently, the KSHV genome was cloned into a bacterial artificial chromosome and used to construct a recombinant KSHV carrying a deletion of the viral interferon regulatory factor gene (F. C. Zhou, Y. J. Zhang, J. H. Deng, X. P. Wang, H. Y. Pan, E. Hettler, and S. J. Gao, J. Virol. 76:6185-6196, 2002). The K8.1 glycoprotein is a structural component of the KSHV particle and is thought to facilitate virus entry by binding to heparan sulfate moieties on cell surfaces. To further address the …

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Differential Alu Mobilization And Polymorphism Among The Human And Chimpanzee Lineages, Dale J. Hedges, Pauline A. Callinan, Richard Cordaux, Jinchuan Xing, Erin Barnes, Mark A. Batzer Jun 2004

Differential Alu Mobilization And Polymorphism Among The Human And Chimpanzee Lineages, Dale J. Hedges, Pauline A. Callinan, Richard Cordaux, Jinchuan Xing, Erin Barnes, Mark A. Batzer

Faculty Publications

Alu elements are primate-specific members of the SINE (short interspersed element) retroposon family, which comprise ∼10% of the human genome. Here we report the first chromosomal-level comparison examining the Alu retroposition dynamics following the divergence of humans and chimpanzees. We find a twofold increase in Alu insertions in humans in comparison to the common chimpanzee (Pan troglodytes). The genomic diversity (polymorphism for presence or absence of the Alu insertion) associated with these inserts indicates that, analogous to recent nucleotide diversity studies, the level of chimpanzee Alu diversity is ∼1.7 times higher than that of humans. Evolutionarily recent Alu subfamily structure …

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Angiotensin I-Converting Enzyme Polymorphisms, Ace Level And Blood Pressure Among Nigerians, Jamaicans And African-Americans, Nourdine Bouzekri, Xiaofeng Zhu, Yanming Jiang, Colin A. Mckenzie, Amy Luke, Terrence Forrester, Adebowale Adeyemo, Donghui Kan, Martin Farrall, Simon Anderson, Richard S. Cooper, Ryk Ward Jun 2004

Angiotensin I-Converting Enzyme Polymorphisms, Ace Level And Blood Pressure Among Nigerians, Jamaicans And African-Americans, Nourdine Bouzekri, Xiaofeng Zhu, Yanming Jiang, Colin A. Mckenzie, Amy Luke, Terrence Forrester, Adebowale Adeyemo, Donghui Kan, Martin Farrall, Simon Anderson, Richard S. Cooper, Ryk Ward

Faculty Publications

The genes in the renin-angiotensin system are important physiologic candidates in studies of the genetic susceptibility to hypertension. Limited information has been available in most studies on the extent of variation in the candidate loci or the modifying effects of different environmental settings. We consequently genotyped 13 polymorphisms at the angiotensin I-converting enzyme (ACE) locus at an average distance of 2 kb in 2776 family members from Nigeria, Jamaica and an African-American community in the US. Allele and haplotype frequencies were similar in the three populations, with modest evidence of European admixture in the US. Two markers were consistently associated …

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Rationale For A New Generation Of Indicators For Coastal Waters, Gerald Niemi, Denice Wardrop, Robert Brooks, Susan Anderson, Valerie Brady, Hans Paerl, Chet Rakocinski, Marius Brouwer, Barbara Levinson, Michael Mcdonald Jun 2004

Rationale For A New Generation Of Indicators For Coastal Waters, Gerald Niemi, Denice Wardrop, Robert Brooks, Susan Anderson, Valerie Brady, Hans Paerl, Chet Rakocinski, Marius Brouwer, Barbara Levinson, Michael Mcdonald

Faculty Publications

More than half the world'S human population lives within 100 km of the coast, and that number is expected to increase by 25% over the next two decades. Consequently, coastal ecosystems are at serious risk. Larger coastal populations and increasing development have led to increased loading of toxic substances, nutrients and pathogens with subsequent algal blooms, hypoxia, beach closures, and damage to coastal fisheries. Recent climate change has led to the rise in sea level with loss of coastal wetlands and saltwater intrusion into coastal aquifers. Coastal resources have traditionally been monitored on a stressor-by-stressor basis such as for nutrient …

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The Impact Of Species Concept On Biodiversity Studies, Keith A. Crandall, Paul-Michael Agapow, Olaf R. P. Bininda-Emonds, John L. Gittleman, Georgina M. Mace, Jonathon C. Marshall, Andy Purvis Jun 2004

The Impact Of Species Concept On Biodiversity Studies, Keith A. Crandall, Paul-Michael Agapow, Olaf R. P. Bininda-Emonds, John L. Gittleman, Georgina M. Mace, Jonathon C. Marshall, Andy Purvis

Faculty Publications

Species are defined using a variety of different operational techniques. While discussion of the various methodologies has previously been restricted mostly to taxonomists, the demarcation of species is also crucial for conservation biology. Unfortunately, different methods of diagnosing species can arrive at different entities. Most prominently, it is widely thought that use of a phylogenetic species concept may lead to recognition of a far greater number of much less inclusive units. As a result, studies of the same group of organisms can produce not only different species identities but also different species range and number of individuals. To assess the …

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Impacts Of A Recurrent Resuspension Event And Variable Phytoplankton Community Composition On Remote Sensing Reflectance, Trisha Bergmann, Gary Fahnenstiel, Steven Lohrenz, David Millie, Oscar Schofield May 2004

Impacts Of A Recurrent Resuspension Event And Variable Phytoplankton Community Composition On Remote Sensing Reflectance, Trisha Bergmann, Gary Fahnenstiel, Steven Lohrenz, David Millie, Oscar Schofield

Faculty Publications

In order to characterize the impact of turbidity plumes on optical and biological dynamics, a suite of environmental parameters were measured in southern Lake Michigan during the springtime recurrent sediment plume. In-water measurements of inherent optical properties (IOPs) were entered into the Hydrolight 4.2 radiative transfer model and the output was compared with measured apparent optical properties (AOPs) across a wide range of optical conditions. Hydrolight output and measured underwater light fields were then used to clarify the effects of the sediment plume on primary production, phytoplankton community composition, and nearshore remote sensing ocean color algorithms. Our results show that …

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Individual Cell Growth Rates Of Marine Bacteria, Measured By Bromodeoxyuridine Incorporation, Koji Hamasaki, Richard A. Long, Farooq Azam May 2004

Individual Cell Growth Rates Of Marine Bacteria, Measured By Bromodeoxyuridine Incorporation, Koji Hamasaki, Richard A. Long, Farooq Azam

Faculty Publications

We tested the application of 5-bromo-2’-deoxyuridine (BrdU), a thymidine analogue that becomes incorporated into DNA during growth, to measure growth rates of individual marine bacteria cells. Immunocytochemical detection of BrdU incorporation into bacterial DNA has the potential for single-cell-based growth measurement. Optimized procedure for immunocytochemistry was applicable to 14 marine heterotrophic bacterial isolates belonging to g-proteobacteria, α-proteobacteria, Cytophaga-Flavobacterium-Bacteroides (CFB) group and Gram-positive bacteria. The relationship between cell-specific fluorescence intensity and specific growth rate was linearly correlated among CFB group isolates, which indicated a potential of the method for quantitative measurement. Analysis of the detection limit indicated …

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Growth And Transport Properties Of Complementary Germanium Nanowire Field Effect Transistors, Andrew B. Greytak, Lincoln J. Lauhon, Mark S. Gudiksen, Charles M. Lieber May 2004

Growth And Transport Properties Of Complementary Germanium Nanowire Field Effect Transistors, Andrew B. Greytak, Lincoln J. Lauhon, Mark S. Gudiksen, Charles M. Lieber

Faculty Publications

n- and p-type Ge nanowires were synthesized by a multistep process in which axial elongation, via vapor–liquid–solid (VLS) growth, and doping were accomplished in separate chemical vapor deposition steps. Intrinsic, single-crystal, Ge nanowires prepared by Au nanocluster-mediated VLS growth were surface-doped in situ using diborane or phosphine, and then radial growth of an epitaxial Ge shell was used to cap the dopant layer. Field-effect transistors prepared from these Ge nanowires exhibited on currents and transconductances up to 850 µA/µm and 4.9 µA/V, respectively, with device yields of >85%.

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Dynamics Of Pectoral Fin Rowing In A Fish With An Extreme Rowing Stroke: The Threespine Stickleback (Gasterosteus Aculeatus), Jeffrey A. Walker Phd May 2004

Dynamics Of Pectoral Fin Rowing In A Fish With An Extreme Rowing Stroke: The Threespine Stickleback (Gasterosteus Aculeatus), Jeffrey A. Walker Phd

Faculty Publications

The dynamics of pectoral fin rowing in the threespine stickleback are investigated by measuring the instantaneous force balance on freely swimming fish throughout the stroke cycle and comparing the measured forces with fin motions and an unsteady, blade-element model of pectoral fin propulsion. Both measured and modeled forces suggest that attached vortex and circulatory forces and not inertial (added mass) forces dominate the force balance. Peak forces occur at midstrokes. There is no evidence for large force peaks at the stroke transitions due to either rapid fin rotation (supination) or rapid fin closure against the body. The energetics of pectoral …

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Identification Of A New Chloroplast Carbonic Anhydrase In Chlamydomonas Reinhardtii, Mautusi Mitra, Scott M. Lato, Ruby A. Ynalvez, Ying Xiao, James V. Moroney May 2004

Identification Of A New Chloroplast Carbonic Anhydrase In Chlamydomonas Reinhardtii, Mautusi Mitra, Scott M. Lato, Ruby A. Ynalvez, Ying Xiao, James V. Moroney

Faculty Publications

Carbonic anhydrases (CA) are zinc-containing metalloenzymes that catalyze the reversible hydration of CO2. The three evolutionarily unrelated families of CAs are designated α-, β-, and γ-CA. Aquatic photosynthetic organisms have evolved different forms of CO2 concentrating mechanisms (CCMs) to aid Rubisco in capturing CO2 from the surrounding environment. One aspect of all CCMs is the critical roles played by various specially localized extracellular and intracellular CAs. Five CAs have previously been identified in Chlamydomonas reinhardtii, a green alga with a well-studied CCM. Here we identify a sixth gene encoding a β-type CA. This new β-CA, designated Cah6, is distinct from …

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Structure Of Fosfomycin Resistance Protein Fosa From Transposon Tn2921, Svetlana Pakhomova, Chris L. Rife, Richard N. Armstrong, Marcia E. Newcomer May 2004

Structure Of Fosfomycin Resistance Protein Fosa From Transposon Tn2921, Svetlana Pakhomova, Chris L. Rife, Richard N. Armstrong, Marcia E. Newcomer

Faculty Publications

The crystal structure of fosfomycin resistance protein FosA from transposon Tn2921 has been established at a resolution of 2.5 Å. The protein crystallized without bound Mn(II) and K+, ions crucial for efficient catalysis, providing a structure of the apo enzyme. The protein maintains the three-dimensional domain-swapped arrangement of the paired βαβββ-motifs observed in the genomically encoded homologous enzyme from Pseudomonas aeruginosa (PA1129). The basic architecture of the active site is also maintained, despite the absence of the catalytically essential Mn(II). However, the absence of K+, which has been shown to enhance enzymatic activity, appears to contribute to conformational heterogeneity in …

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Properties And Performance Of The Prototype Instrument For The Pierre Auger Observatory, J. Abraham, M. Aglietta, I. C. Aguirre, M. Albrow, D. Allard, I. Allekotte, P. Allison, J. Alvarez Muñiz, M. G. Do Amaral, M. Ambrosio, L. Anchordoqui, R. Andrews, M. Anguiano, J. C. Dos Anjos, C. Aramo, S. Argiro, K. Arisaka, J. C. Arteaga, S. Atulugama, M. Ave, G. Avila, R. Baggio, X. Bai, A. F. Barbosa, H. M.J. Barbosa, D. Barnhill, S. L.C. Barroso, P. Bauleo, J. Beatty, T. Beau, K. H. Becker, J. A. Bellido, P. Bello May 2004

Properties And Performance Of The Prototype Instrument For The Pierre Auger Observatory, J. Abraham, M. Aglietta, I. C. Aguirre, M. Albrow, D. Allard, I. Allekotte, P. Allison, J. Alvarez Muñiz, M. G. Do Amaral, M. Ambrosio, L. Anchordoqui, R. Andrews, M. Anguiano, J. C. Dos Anjos, C. Aramo, S. Argiro, K. Arisaka, J. C. Arteaga, S. Atulugama, M. Ave, G. Avila, R. Baggio, X. Bai, A. F. Barbosa, H. M.J. Barbosa, D. Barnhill, S. L.C. Barroso, P. Bauleo, J. Beatty, T. Beau, K. H. Becker, J. A. Bellido, P. Bello

Faculty Publications

Construction of the first stage of the Pierre Auger Observatory has begun. The aim of the Observatory is to collect unprecedented information about cosmic rays above 1018 eV. The first phase of the project, the construction and operation of a prototype system, known as the engineering array, has now been completed. It has allowed all of the sub-systems that will be used in the full instrument to be tested under field conditions. In this paper, the properties and performance of these sub-systems are described and their success illustrated with descriptions of some of the events recorded thus far. © 2003 …

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Diode Laser Microwave Induced Plasma Cavity Ringdown Spectrometer: Performance And Perspective, Chuji Wang, Sudip P. Koirala, Susan T. Scherrer, Yixiang Duan, Christopher B. Winstead May 2004

Diode Laser Microwave Induced Plasma Cavity Ringdown Spectrometer: Performance And Perspective, Chuji Wang, Sudip P. Koirala, Susan T. Scherrer, Yixiang Duan, Christopher B. Winstead

Faculty Publications

Recent studies combining an atmospheric-pressure plasma source (inductively coupled plasma or microwave induced plasma) with cavity ringdown spectroscopy (plasma-CRDS) have indicated significant promise for ultra-sensitive elemental measurements. Initial plasma-CRDS efforts employed an inductively coupled plasma as the atomization source and a pulsed laser system as the light source. In an effort to improve the portability and reduce the cost of the system for application purposes, we have modified our approach to include a compact microwave induced plasma and a continuous wave diode laser. A technique for controlling the coupling of the continuous wave laser to the ringdown cavity has been …

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Identification Of An Il-17-Producing Nk1.1neg Inkt Cell Population Involved In Airway Neutrophilia, Paul B. Savage, Marie-Laure Michel, Alexandre Castro Keller, Christophe Paget, Masakazu Fujio, Francois Trottein, Chi-Huey Wong, Elke Schneider, Michael Dy, Maria C. Leite-De-Moraes Apr 2004

Identification Of An Il-17-Producing Nk1.1neg Inkt Cell Population Involved In Airway Neutrophilia, Paul B. Savage, Marie-Laure Michel, Alexandre Castro Keller, Christophe Paget, Masakazu Fujio, Francois Trottein, Chi-Huey Wong, Elke Schneider, Michael Dy, Maria C. Leite-De-Moraes

Faculty Publications

Invariant natural killer T (iNKT) cells are an important source of both T helper type 1 (Th1) and Th2 cytokines, through which they can exert beneficial, as well as deleterious, effects in a variety of inflammatory diseases. This functional heterogeneity raises the question of how far phenotypically distinct subpopulations are responsible for such contrasting activities. In this study, we identify a particular set of iNKT cells that lack the NK1.1 marker (NK1.1neg) and secrete high amounts of interleukin (IL)-17 and low levels of interferon (IFN)-{gamma} and IL-4. NK1.1neg iNKT cells produce IL-17 upon synthetic ({alpha}-galactosylceramide [{alpha}-GalCer] or PBS-57), as well …

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Noble Metal Nanostructures Synthesized Inside Mesoporous Nanotemplate Pores, J. Arbiol, E. Rossinyol, A. Cabot, F. Peiro, A. Cornet, J. R. Morante, Fanglin Chen, Meilin Liu Apr 2004

Noble Metal Nanostructures Synthesized Inside Mesoporous Nanotemplate Pores, J. Arbiol, E. Rossinyol, A. Cabot, F. Peiro, A. Cornet, J. R. Morante, Fanglin Chen, Meilin Liu

Faculty Publications

Noble metal impregnation has resulted in the inclusion of metal nanostructures within the SBA-15 mesoporous silica hexagonal pores (from nanoclusters to nanowires). A bright-field transmission electron microscopy three-dimensional reconstruction is proposed to analyze the localization of nanostructures within the pores of mesoporous nanotemplates. The method allows corroboration whether the nanostructures are synthesized inside the pores or they are synthesized alternatively on the nanotemplate aggregates exterior surface.

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Molecular-Dynamics Simulation Of The Effect Of Ions On A Liquid–Liquid Interface For A Partially Miscible Mixture, Richard L. Rowley, Kent E. Wardle, Eric Carlson, Douglas Henderson Apr 2004

Molecular-Dynamics Simulation Of The Effect Of Ions On A Liquid–Liquid Interface For A Partially Miscible Mixture, Richard L. Rowley, Kent E. Wardle, Eric Carlson, Douglas Henderson

Faculty Publications

Molecular-dynamics simulations were performed to model the effect of added salt ions on the liquid-liquid interface in a partially miscible system. Simulations of the interface between saturated phases of a model 1-hexanol + water system show a bilayer structure of 1-hexanol molecules at the interface with OH heads of the first layer directed into the water phase and the opposite orientation for the second layer. The alignment of the polar OH groups at the interface stabilizes a charge separation of sodium and chloride ions when salt is introduced into the aqueous phase, producing an electrical double layer. Chloride ions aggregate …

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Characterization Of Iron Binding In Isca, An Ancient Iron-Sulphur Cluster Assembly Protein, Huangen Ding, Robert J. Clark Apr 2004

Characterization Of Iron Binding In Isca, An Ancient Iron-Sulphur Cluster Assembly Protein, Huangen Ding, Robert J. Clark

Faculty Publications

Iron-sulphur clusters are one of the most common types of redox centre in biology. At least six proteins (IscS, IscU, IscA, HscB, HscA and ferredoxin) have been identified as being essential for the biogenesis of iron-sulphur proteins in bacteria. It has been shown that IscS is a cysteine desulphurase that provides sulphur for iron-sulphur clusters, and that IscU is a scaffold for the IscS-mediated assembly of iron-sulphur clusters. The iron donor for iron-sulphur clusters, however, remains elusive. Here we show that IscA is an iron binding protein with an apparent iron association constant of 3.0 × 1019 M-1, and that …

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