Search Results - (Author, Cooperation:K. Marsh)
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1Latest Papers from Table of Contents or Articles in PressM. Manske ; O. Miotto ; S. Campino ; S. Auburn ; J. Almagro-Garcia ; G. Maslen ; J. O'Brien ; A. Djimde ; O. Doumbo ; I. Zongo ; J. B. Ouedraogo ; P. Michon ; I. Mueller ; P. Siba ; A. Nzila ; S. Borrmann ; S. M. Kiara ; K. Marsh ; H. Jiang ; X. Z. Su ; C. Amaratunga ; R. Fairhurst ; D. Socheat ; F. Nosten ; M. Imwong ; N. J. White ; M. Sanders ; E. Anastasi ; D. Alcock ; E. Drury ; S. Oyola ; M. A. Quail ; D. J. Turner ; V. Ruano-Rubio ; D. Jyothi ; L. Amenga-Etego ; C. Hubbart ; A. Jeffreys ; K. Rowlands ; C. Sutherland ; C. Roper ; V. Mangano ; D. Modiano ; J. C. Tan ; M. T. Ferdig ; A. Amambua-Ngwa ; D. J. Conway ; S. Takala-Harrison ; C. V. Plowe ; J. C. Rayner ; K. A. Rockett ; T. G. Clark ; C. I. Newbold ; M. Berriman ; B. MacInnis ; D. P. Kwiatkowski
Nature Publishing Group (NPG)
Published 2012Staff ViewPublication Date: 2012-06-23Publisher: Nature Publishing Group (NPG)Print ISSN: 0028-0836Electronic ISSN: 1476-4687Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsKeywords: Alleles ; *Biodiversity ; Genome, Protozoan ; Genotype ; *High-Throughput Nucleotide Sequencing ; Humans ; Malaria, Falciparum/*parasitology ; Phylogeny ; Plasmodium falciparum/classification/*genetics ; Polymorphism, Single Nucleotide ; Principal Component AnalysisPublished by: -
2Latest Papers from Table of Contents or Articles in PressChada, N., Chattrakun, K., Marsh, B. P., Mao, C., Bariya, P., King, G. M.
American Association for the Advancement of Science (AAAS)
Published 2018Staff ViewPublication Date: 2018-10-25Publisher: American Association for the Advancement of Science (AAAS)Electronic ISSN: 2375-2548Topics: Natural Sciences in GeneralPublished by: -
3Latest Papers from Table of Contents or Articles in PressJ. Tan ; K. Pieper ; L. Piccoli ; A. Abdi ; M. Foglierini ; R. Geiger ; C. M. Tully ; D. Jarrossay ; F. M. Ndungu ; J. Wambua ; P. Bejon ; C. S. Fregni ; B. Fernandez-Rodriguez ; S. Barbieri ; S. Bianchi ; K. Marsh ; V. Thathy ; D. Corti ; F. Sallusto ; P. Bull ; A. Lanzavecchia
Nature Publishing Group (NPG)
Published 2015Staff ViewPublication Date: 2015-12-25Publisher: Nature Publishing Group (NPG)Print ISSN: 0028-0836Electronic ISSN: 1476-4687Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsKeywords: Amino Acid Sequence ; Antibodies, Monoclonal/chemistry/genetics/*immunology/therapeutic use ; *Antibody Specificity ; Antigenic Variation/*immunology ; Antigens, Protozoan/*immunology ; B-Lymphocytes/cytology/immunology ; Clone Cells/cytology/immunology ; Collagen/immunology/metabolism ; Conserved Sequence/immunology ; DNA Transposable Elements/genetics/immunology ; Epitopes, B-Lymphocyte/chemistry/immunology ; Erythrocytes/immunology/metabolism/parasitology ; Humans ; Kenya ; Malaria/*immunology/parasitology ; Malaria Vaccines/chemistry/immunology ; Membrane Proteins/chemistry/immunology ; Molecular Sequence Data ; Mutagenesis, Insertional/*genetics ; Plasmodium falciparum/*immunology ; Protein Structure, Tertiary/genetics ; Protozoan Proteins/chemistry/immunology ; Receptors, Immunologic/chemistry/genetics/*immunology/metabolismPublished by: -
4Latest Papers from Table of Contents or Articles in PressErber, A. C., Arana, B., Bennis, I., Ben Salah, A., Boukthir, A., Castro Noriega, M. d. M., Cisse, M., Cota, G. F., Handjani, F., Kebede, M. G., Lang, T., Lopez Carvajal, L., Marsh, K., Martinez Medina, D., Plugge, E., Olliaro, P.
BMJ Publishing
Published 2018Staff ViewPublication Date: 2018-06-17Publisher: BMJ PublishingElectronic ISSN: 2044-6055Topics: MedicineKeywords: Open access, Qualitative researchPublished by: -
5Latest Papers from Table of Contents or Articles in PressN. M. Pedatella, H.-L Liu, D. R. Marsh, K. Raeder, J. L. Anderson, J. L. Chau, L. P. Goncharenko, T. A. Siddiqui
Wiley-Blackwell
Published 2018Staff ViewPublication Date: 2018-03-16Publisher: Wiley-BlackwellPrint ISSN: 0148-0227Topics: GeosciencesPhysicsPublished by: -
6Latest Papers from Table of Contents or Articles in PressAunins, T. R., Marsh, K. A., Subramanya, G., Uprichard, S. L., Perelson, A. S., Chatterjee, A.
The American Society for Microbiology (ASM)
Published 2018Staff ViewPublication Date: 2018-05-15Publisher: The American Society for Microbiology (ASM)Print ISSN: 0022-538XElectronic ISSN: 1098-5514Topics: MedicinePublished by: -
7Articles: DFG German National LicensesArrieta, E. ; Jedrzejek, C. ; Marsh, K. N.
College Park, Md. : American Institute of Physics (AIP)
Published 1991Staff ViewISSN: 1089-7690Source: AIP Digital ArchiveTopics: PhysicsChemistry and PharmacologyNotes: An efficient algorithm is given to find the Blum and Høye mean spherical approximation (MSA) solution for mixtures of hard-core fluids with multi-Yukawa interactions. The initial estimation of the variables is based on the asymptotic high-temperature behavior of the fluid. From this initial estimate only a few Newton–Raphson iterations are required to reach the final solution. The algorithm consistently yields the unique thermodynamically stable solution, whenever it exists, i.e., whenever the fluid appears as a single, homogeneous phase. For conditions in which no single phase can appear, the algorithm will declare the absence of solutions or, less often, produce thermodynamically unstable solutions. A simple criterion reveals the instability of those solutions. Furthermore, this Yukawa-MSA algorithm can be used in a most simple way to estimate the onset of thermodynamic instability and to predict the nature of the resulting phase separation (whether vapor–liquid or liquid–liquid). Specific results are presented for two binary multi-Yukawa mixtures. For both mixtures, the Yukawa interaction parameters were adjusted to fit, beyond the hard-core diameters σ, Lennard-Jones potentials. Therefore the potentials studied, although strictly negative, included a significant repulsion interval. The characteristics of the first mixture were chosen to produce a nearly ideal solution, while those of the second mixture favored strong deviations from ideality. The MSA algorithm was able to reflect correctly their molecular characteristics into the appropriate macroscopic behavior, reproducing not only vapor–liquid equilibrium but also liquid–liquid separations. Finally, the high-density limit of the fluid phase was determined by requiring the radial distribution function to be non-negative. A case is made for interpreting that limit as the fluid–glass transition.Type of Medium: Electronic ResourceURL: -
8Articles: DFG German National LicensesArrieta, E. ; Jedrzejek, C. ; Marsh, K. N.
College Park, Md. : American Institute of Physics (AIP)
Published 1991Staff ViewISSN: 1089-7690Source: AIP Digital ArchiveTopics: PhysicsChemistry and PharmacologyNotes: Monte Carlo (MC) simulations are used to determine the properties of two different binary multi-Yukawa mixtures studied previously through a quasianalytic Yukawa-MSA (mean spherical approximation) algorithm [Arrieta, Jedrzejek, and Marsh, J. Chem. Phys. 95 XXXX (1991)]. These mixtures are composed of spherical hard-core molecules with multi-Yukawa interactions fitted (beyond the core diameters σLJij) to Lennard-Jones potentials, including thus a significant repulsion (negative slope) interval. The characteristics of the first mixture were chosen to produce a nearly ideal solution, while those of the second mixture (large size difference between components, weak unlike-particle attractions) favored nonideal behavior. For a variety of compositions, densities (in the liquid range), and temperatures, the following properties are determined: configurational energy, pressure, and chemical potentials. The latter were obtained through a new implementation of Widom's particle insertion method. This simple implementation allowed the calculation of chemical potentials at high densities, where the usual procedures tend to fail. An analysis of the standard deviations and of the internal consistency of the MC data was used to confirm the general reliability of the simulation results. The good general agreement found between MC and MSA leads to the conclusion that the Yukawa-MSA quasianalytic algorithm provides not only a convenient but an accurate description of dense fluid mixtures, both ideal and nonideal.Type of Medium: Electronic ResourceURL: -
9Articles: DFG German National LicensesJoshi, C. ; Blue, B. ; Clayton, C. E. ; Dodd, E. ; Huang, C. ; Marsh, K. A. ; Mori, W. B. ; Wang, S.
[S.l.] : American Institute of Physics (AIP)
Published 2002Staff ViewISSN: 1089-7674Source: AIP Digital ArchiveTopics: PhysicsNotes: An intense, high-energy electron or positron beam can have focused intensities rivaling those of today's most powerful laser beams. For example, the 5 ps (full-width, half-maximum), 50 GeV beam at the Stanford Linear Accelerator Center (SLAC) at 1 kA and focused to a 3 micron rms spot size gives intensities of 〉1020 W/cm−2 at a repetition rate of 〉10 Hz. Unlike a ps or fs laser pulse which interacts with the surface of a solid target, the particle beam can readily tunnel through tens of cm of steel. However, the same particle beam can be manipulated quite effectively by a plasma that is a million times less dense than air! This is because of the incredibly strong collective fields induced in the plasma by the Coulomb force of the beam. The collective fields in turn react back onto the beam leading to many clearly observable phenomena. The beam paraticles can be: (1) Deflected leading to focusing, defocusing, or even steering of the beam; (2) undulated causing the emission of spontaneous betatron x-ray radiation and; (3) accelerated or decelerated by the plasma fields. Using the 28.5 GeV electron beam from the SLAC linac a series of experiments have been carried out that demonstrate clearly many of the above mentioned effects. The results can be compared with theoretical predictions and with two-dimensional and three-dimensional, one-to-one, particle-in-cell code simulations. These phenomena may have practical applications in future technologies including optical elements in particle beam lines, synchrotron light sources, and ultrahigh gradient accelerators. © 2002 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
10Articles: DFG German National LicensesLal, A. K. ; Gordon, D. ; Wharton, K. ; Clayton, C. E. ; Marsh, K. A. ; Mori, W. B. ; Joshi, C.
[S.l.] : American Institute of Physics (AIP)
Published 1997Staff ViewISSN: 1089-7674Source: AIP Digital ArchiveTopics: PhysicsNotes: The dynamics of a relativistic plasma wave (RPW) resonantly excited by a two frequency CO2 laser pulse and the effects of this wave on a co-propagating relativistic electron beam were studied through experiments and supporting simulations. The amplitude of the RPW and its harmonics were resolved in time and space with a Thomson scattering diagnostic. In addition, the plasma wave amplitude-length product and temporal duration were independently measured through time and frequency resolved forward scattering. The transverse electric and magnetic fields associated with the RPW were studied by the scattering of a 2 MeV electron beam, and the eventual heating of the plasma after the breakup of the RPW was measured from the x-ray radiation spectrum. The experiments and simulations show that the RPW reaches a peak amplitude of approximately 30%, with the amplitude limited by plasma blowout driven by the radial ponderomotive forces of the plasma wave. © 1997 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
11Articles: DFG German National LicensesClayton, C. E. ; Everett, M. J. ; Lal, A. ; Gordon, D. ; Marsh, K. A. ; Joshi, C.
[S.l.] : American Institute of Physics (AIP)
Published 1994Staff ViewISSN: 1089-7674Source: AIP Digital ArchiveTopics: PhysicsNotes: The results from experiments in which a two-frequency CO2 laser is used to beat-excite large-amplitude, relativistic electron plasma waves in a tunnel-ionized plasma are reported. The plasma wave is diagnosed by injecting a beam of 2 MeV electrons and observing the energy gain and loss of these electrons, as well as the scattering and deflection of the transmitted electrons near 2 MeV. Accelerated electrons up to 30 MeV have been observed. The lifetime of the accelerating structure as seen by small-angle Thomson scattering is about 100 ps, whereas the injected electrons are seen to be scattered or deflected by the plasma for several ns, with diffuse scattering occurring 0.5–1 ns after forming the plasma wave and whole beam deflection occurring at later times. A simple model, which includes laser focusing, ionization, transit time, and relativistic saturation effects, suggests that the wave coherence may be short lived while the wave fields themselves persist for a longer time. This may be the reason for the disparate time scales between the Thomson scattering and the electron scattering diagnostic. The whole beam deflection may be evidence for a Weibel-like instability at later times.Type of Medium: Electronic ResourceURL: -
12Articles: DFG German National LicensesStaff View
ISSN: 1089-7623Source: AIP Digital ArchiveTopics: PhysicsElectrical Engineering, Measurement and Control TechnologyNotes: A small, high performance electron linear accelerator is described. It is a modified version of a commercially available portable x-ray source. The 9.3 GHz rf linac and beamline deliver a 3 ns train of approximately 15 ps pulses with a peak current, limited by beam loading of the rf structure, of more than 100 mA and a beam energy of around 2 MeV with a 5% full width at half maximum energy spread. The beam emittance is 6π mm mrad and the final spot size is 250 μm diam for f/10 focusing.Type of Medium: Electronic ResourceURL: -
13Articles: DFG German National LicensesRogers, W. J. ; Fontalba, F. ; Capps, E. F. ; Holste, J. C. ; Marsh, K. N. ; Hall, K. R.
[S.l.] : American Institute of Physics (AIP)
Published 1988Staff ViewISSN: 1089-7623Source: AIP Digital ArchiveTopics: PhysicsElectrical Engineering, Measurement and Control TechnologyNotes: This note presents designs for two inexpensive, magnetic circulating pumps. The first pump is designed for corrosive fluids over wide ranges of temperature, to 700 K, and pressure, to 200 MPa, and for flow rates to 6 cm3/s. The second pump is designed primarily for gases at temperatures to 500 K, pressures from 6 kPa to 20 MPa, and flow rates to 60 cm3/s. Each pump consists of a simple cylinder and piston with a central flow channel and gate operated by sample inertia.Type of Medium: Electronic ResourceURL: -
14Articles: DFG German National LicensesMarsh, K. ; Joshi, C. ; Janesick, J. ; Collins, S.
[S.l.] : American Institute of Physics (AIP)
Published 1985Staff ViewISSN: 1089-7623Source: AIP Digital ArchiveTopics: PhysicsElectrical Engineering, Measurement and Control TechnologyNotes: An 800×800 Texas Instruments virtual phase charge-coupled device (CCD) was used to obtain pinhole images and x-ray spectra of laser-produced, solid target plasmas. With the CCD used in the single-photon counting mode, the spectrum in the energy range 2–10 keV was obtained without a dispersive element. Typical spectra reveal two distinct temperatures: a "cold'' component of approximately 200 eV and "hot'' component of approximately 5 keV. Also, multiline spectra comprising characteristic line emission (Kα, Kβ) from a multilayer target bombarded by β rays were recorded using a three-phase CCD. The results demonstrate the potential of CCDs as imaging spectrometers with application in space, laboratory, and fusion plasma research.Type of Medium: Electronic ResourceURL: -
15Articles: DFG German National LicensesStaff View
ISSN: 1749-6632Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: Natural Sciences in GeneralType of Medium: Electronic ResourceURL: -
16Articles: DFG German National LicensesArrieta, E. ; Je¸drzejek, C. ; Marsh, K. N.
College Park, Md. : American Institute of Physics (AIP)
Published 1987Staff ViewISSN: 1089-7690Source: AIP Digital ArchiveTopics: PhysicsChemistry and PharmacologyNotes: An efficient numerical algorithm is given to find the Blum and Høye mean spherical approximation (MSA) solution for binary mixtures of hard-core fluids with one-Yukawa interactions. The initial estimation of the variables is achieved by partial linearization (based on known, physical asymptotic behaviors) of the system of nonlinear equations which result from the Blum and Høye method. The complete procedure is at least one order of magnitude faster than that recently outlined by Giunta et al. More importantly, it always seems to converge to the physical solution (if it exists). We delimit, for several specific mixtures, the density-temperature region where no real solution is possible. This corresponds, following Waisman's interpretation, to thermodynamic conditions for which vapor–liquid or liquid–liquid separation occurs. The dependency of the MSA solutions on the Yukawa exponent z is studied in detail. For high values of z, adequate for generalized mean spherical approximation (GMSA) applications, we propose an accurate linear approximation, and we relate it to the solutions given by Giunta et al. For equal-sized, symmetric, equimolar binary mixtures, we show that Baxter's factorized version of the Ornstein–Zernike equation, including the factor correlation functions, can be decoupled. We also find, for equal-sized mixtures, that one of the approximations recently proposed by Jedrzejek et al. using an effective potential method is in very good agreement with our exact (MSA) results. Finally, a theoretical analysis shows that if the Yukawa amplitudes satisfy K12=(K11K22)1/2, the coefficients Dij of the factor correlation functions outside the core are related as follows: D1i/K1i =D2i/K2i, for i=1,2.Type of Medium: Electronic ResourceURL: -
17Articles: DFG German National LicensesRICHARDSON, A. C. ; MARSH, K. B. ; BOLDINGH, H. L. ; PICKERING, A. H. ; BULLEY, S. M. ; FREARSON, N. J. ; FERGUSON, A. R. ; THORNBER, S. E. ; BOLITHO, K. M. ; MACRAE, E. A.
Oxford, UK : Blackwell Science Ltd
Published 2004Staff ViewISSN: 1365-3040Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: BiologyNotes: Kiwifruit vines are perennial plants grown in climates varying from maritime to continental. To determine key responses to temperature, vines were heated at different stages of fruit development, and vine growth and fruit composition examined. Heating vines during fruit starch accumulation caused a major shift in partitioning towards vegetative growth and dramatically reduced fruit carbohydrate and vitamin C. In the following season, growth and flowering were severely reduced. Heating vines during fruit cell division had minimal long-term effects, whereas heating during fruit maturation delayed starch degradation and fruit ripening and affected growth in the following season. When vines were removed from heat, fruit dry matter, starch and sugar levels were always reduced but hexose : sucrose ratios and inositol were raised. Heating vines affected expression of two sucrose synthase genes, but this did not correlate with reduction in fruit carbohydrate. Activity and expression of l-galactose dehydrogenase decreased as fruit developed, suggesting some vitamin C biosynthesis must take place in the fruit. Activity and expression of actinidin increased in response to heat. The results of this study have demonstrated both short and long-term plant responses to elevated temperatures in woody perennials, and that the timing of heat exposure has severe consequences for vitamin C levels in fruit.Type of Medium: Electronic ResourceURL: -
18Articles: DFG German National LicensesNyakeriga, A. M. ; Troye-Blomberg, M. ; Chemtai, A. K. ; Marsh, K. ; Williams, T. N.
Oxford, UK; Malden, USA : Blackwell Science Ltd/Inc.
Published 2004Staff ViewISSN: 1365-3083Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: MedicineNotes: The relationship between malnutrition and malaria is controversial. On one hand, malaria may cause malnutrition, while on the other, malnutrition itself may modulate susceptibility to the disease. We investigated the association between Plasmodium falciparum malaria and malnutrition in a cohort of children living on the coast of Kenya. The study involved longitudinal follow-up for clinical malaria episodes and anthropometric measurements at four cross-sectional surveys. We used Poisson regression analysis to investigate the association between malaria and nutritional status. Compared to baseline (children with a WAZ or HAZ score of ≥−2), the crude incidence rate ratios (IRRs) for malaria in children with low HAZ or WAZ scores (〈−2) during the period prior to assessment were 1.17 (95% CI 0.91–1.50; 0 = 0.21) and 0.94 (0.71–1.25; 0.67), respectively, suggesting no association between malaria and the subsequent development of PEM. However, we found that age was acting as an effect modifier in the association between malaria and malnutrition. The IRR for malaria in children 0–2 years old who were subsequently characterized as wasted was 1.65 (1.10–2.20; P = 0.01), and a significant overall relationship between malaria and low-HAZ was found on regression analysis when adjusting for the interaction with age (IRR 1.89; 1.01–3.53; P 〈 0.05). Although children living on the coast of Kenya continue to suffer clinical episodes of uncomplicated malaria throughout their first decade, the association between malaria and malnutrition appears to be limited to the first 2 years of life.Type of Medium: Electronic ResourceURL: -
19Articles: DFG German National LicensesNyakeriga, A. M. ; Williams, T. N. ; Marsh, K. ; Wambua, S. ; Perlmann, H. ; Perlmann, P. ; Grandien, A. ; Troye-Blomberg, M.
Oxford, UK; Malden, USA : Blackwell Science Ltd
Published 2005Staff ViewISSN: 1365-3083Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: MedicineNotes: Iron deficiency has been reported to affect both malaria pathogenesis and cell-mediated immune responses; however, it is unclear whether the protection afforded by iron deficiency is mediated through direct effects on the parasite, through immune effector functions or through both. We have determined cytokine mRNA expression levels in 59 children living in a malaria endemic area on the coast of Kenya who we selected on the basis of their biochemical iron status. Real-time quantitative reverse transcriptase polymerase chain reaction analysis of cytokine mRNA levels of peripheral blood mononuclear cells (PBMC) obtained from these children showed an association between interleukin-4 (IL-4) mRNA levels and all the biochemical indices of iron that we measured. Furthermore, IL-10 mRNA was higher in parasite blood smear-positive children than in blood smear-negative children irrespective of their iron status. This study suggests that IL-4 expression by PBMC may be affected by iron status.Type of Medium: Electronic ResourceURL: -
20Articles: DFG German National LicensesStaff View
ISSN: 1476-4687Source: Nature Archives 1869 - 2009Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsNotes: [Auszug] In Table 1 and Fig. 1 we give the measured flux density values for Cygnus X-3. Allowance has been made for the effects of confusion, using data provided by P. C. Gregory which had been derived from observations of the first recorded outburst. The error bars are standard deviations representing the ...Type of Medium: Electronic ResourceURL: