952 research outputs found
Evaluation and comparison of spinning disc (CDA) and low pressure (LP) nozzles with conventional flat fan nozzles
Non-Peer Reviewe
Food web structure and mercury transfer in two contrasting Ugandan highland crater lakes (East Africa)
Abstract in English and FrenchVolcanic crater lakes scattered throughout western Uganda are important local sources of water and fish. Two representative but contrasting crater lakes near the Kibale National Park were sampled in 2000; the hyper-eutrophic Lake Saka, which is highly affected by agricultural practices, and the mesotrophic Lake Nkuruba that is still surrounded by intact forest. The food web structures in these
two lakes were assessed using stable nitrogen (d15N) and carbon (d13C) isotope analyses, and the mercury (THg) transfer patterns were quantified. The d15N results indicate that food webs in both lakes are abbreviated, with only one to two trophic levels from primary consumers. The Lake Saka biota had distinctively enriched d13C values compared with those in Lake Nkuruba, which may be due to 12C-limited phytoplankton blooms in this lake. In Lake Nkuruba, two introduced tilapiine species and the introduced guppy Poecilia reticulata fed predominantly upon invertebrates and decomposed terrestrial plant material. In Lake Saka, the introduced Nile perch Lates niloticus appeared to occupy the top trophic position, but stable isotope values of the endemic haplochromine cichlids exclude those as Nile perch prey items. THg was found to biomagnify through the food web, reaching highest concentrations in P. reticulata in Nkuruba, which tended to be higher than for L. niloticus in Saka, suggesting increased bioavailability of THg in Nkuruba. Maximum THg concentrations in fish never approached WHO recommended guidelines (200 ng g-1) designed to protect at-risk groups
Differences between tree species in hydraulic press calibration of leaf water potential are correlated with specific leaf area
. To determine the usefulness of the J-14 Hydraulic Press (Campbell Scientific, Inc., Logan, Utah, U.S.A.) in estimating leaf water potential, we calibrated the J-14 Press against a Scholander-type pressure chamber for leaves of various tree species. The species tested were: Acer saccharum, Acer negundo, Acer rubrum. Populus tremuloides, Populus grandidentata, Quercus rubra , and Brassaia actinophylla (Schefflera). The regression calibrations were linear with standard errors about the regression less than 0.1 MPa. The regression equations for the four genera were significantly different, with the y- intercept increasing and the slope decreasing in order of decreasing specific leaf area (SLA). There were no significant differences between species of the calibration lines within the genera Acer and Populus. These data may indicate that leaves with lower SLA resist mechanical compression by the hydraulic press, causing the J-14 Press to be less sensitive to differences of leaf water potential. Therefore the J-14 Press is only a relative measure of leaf water status and does not measure leaf water potential.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73416/1/1365-3040.ep11591871.pd
2,3,8-trisubstituted quinolines with antimalarial activity
FUNDAĂĂO DE AMPARO Ă PESQUISA DO ESTADO DE SĂO PAULO - FAPESPCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTĂFICO E TECNOLĂGICO - CNPQCombination therapy drugs are considered a fundamental way to control malaria as it mimimizes the risk of emergence of resistance to the individual partner drugs. Consequently, this type of therapy constitutes a driving force for the discovery of new drug901212151231FUNDAĂĂO DE AMPARO Ă PESQUISA DO ESTADO DE SĂO PAULO - FAPESPCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTĂFICO E TECNOLĂGICO - CNPQFUNDAĂĂO DE AMPARO Ă PESQUISA DO ESTADO DE SĂO PAULO - FAPESPCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTĂFICO E TECNOLĂGICO - CNPQSEM INFORMAĂĂOSEM INFORMAĂĂOWe especially thank Prof. Marcos Eberlin (Thomsom Laboratory) for HRMS analyses. We are grateful to Sergio Wittlin, Sibylle Sax and the Swiss Tropical and Public Health Institute (Basel, Switzerland) for conducting the resistance assays. We thank Mark We
Recommended from our members
New developments in pulsed fields at the US National High Magnetic Field Laboratory
Los Alamos National Laboratory is a member of a consortium (with Florida State University and the University of Florida) to operate the National High Magnetic Field Laboratory (NHMFL), with funding from the National Science Foundation and the State of Florida. Los Alamos provides unique resources for its component of NHMFL in the form of a 1.4 GW inertial storage motor-generator for high field pulsed magnets and infrastructure for fields generated by flux compression. The NHMFL provides a user facility open to all qualified users, develops magnet technology in association with the private sector, and advances science and technology opportunities. The magnets in service at Los Alamos are of three types. Starting with the pre-existing explosive flux compression capability in 1991, NHMFL added capacitor-driven magnets in December, 1992, and a 20 tesla superconducting magnet in January, 1993. The capacitor-driven magnets continue to grow in diversity and accessibility, with four magnet stations now available for several different magnet types. Two magnets of unprecedented size and strength are nearing completion of assembly and design, respectively. Under final assembly is a quasi-continuous magnet that contains 90 MJ of magnetic energy at full field, and being designed is a non-destructive 100 T magnet containing 140 MJ
Knot soliton in Weinberg-Salam model
We study numerically the topological knot solution suggested recently in the
Weinberg-Salam model. Applying the SU(2) gauge invariant Abelian projection we
demonstrate that the restricted part of the Weinberg-Salam Lagrangian
containing the interaction of the neutral boson with the Higgs scalar can be
reduced to the Ginzburg-Landau model with the hidden SU(2) symmetry. The energy
of the knot composed from the neutral boson and Higgs field has been evaluated
by using the variational method with a modified Ward ansatz. The obtained
numerical value is 39 Tev which provides the upper bound on the electroweak
knot energy.Comment: 6 pages, 3 figures, analysis of stability adde
Universality of Frequency and Field Scaling of the Conductivity Measured by Ac-Susceptibility of a Ybco-Film
Utilizing a novel and exact inversion scheme, we determine the complex linear
conductivity from the linear magnetic ac-susceptibility
which has been measured from 3\,mHz to 50\,MHz in fields between 0.4\,T and
4\,T applied parallel to the c-axis of a 250\,nm thin disk. The frequency
derivative of the phase and the dynamical scaling of
above and below provide clear evidence for a
continuous phase transition at to a generic superconducting state. Based
on the vortex-glass scaling model, the resulting critical exponents and
are close to those frequently obtained on films by other means and
associated with an 'isotropic' vortex glass. The field effect on
can be related to the increase of the glass coherence length,
.Comment: 8 pages (5 figures upon request), revtex 3.0, APK.94.01.0
Scalable data management in distributed information systems
[EN] In the era of cloud computing and huge information systems, distributed applications should manage dynamic workloads; i.e., the amount of client requests per time unit may vary frequently and servers should rapidly adapt their computing efforts to those workloads. Cloud systems provide a solid basis for this kind of applications but most of the traditional relational database systems are unprepared to scale up with this kind of distributed systems. This paper surveys different techniques being used in modern SQL, NoSQL and NewSQL systems in order to increase the scalability and adaptability in the management of persistent data. © 2011 Springer-Verlag.This work has been supported by EU FEDER and Spanish MICINN under research grants TIN2009-14460-C03-01 and TIN2010-17193PallardĂł Lozoya, MR.; Esparza Peidro, J.; GarcĂa Escriva, JR.; Decker, H.; Muñoz EscoĂ, FD. (2011). Scalable data management in distributed information systems. Lecture Notes in Computer Science. 7046:208-217. https://doi.org/10.1007/978-3-642-25126-9_31S2082177046Helland, P.: Life beyond distributed transactions: an apostateâs opinion. In: 3rd Biennial Conf. on Innov. Data Syst. Research (CIDR), Asilomar, CA, USA, pp. 132â141 (2007)Finkelstein, S., Jacobs, D., Brendle, R.: Principles for inconsistency. In: 4th Biennial Conf. on Innov. Data Syst. Research (CIDR), Asilomar, CA, USA (2009)Chang, F., Dean, J., Ghemawat, S., Hsieh, W.C., Wallach, D.A., Burrows, M., Chandra, T., Fikes, A., Gruber, R.: Bigtable: A distributed storage system for structured data. In: 7th Symp. on Operat. Syst. Design and Implem. (OSDI), pp. 205â218. USENIX Assoc., Seattle (2006)Cooper, B.F., Baldeschwieler, E., Fonseca, R., Kistler, J.J., Narayan, P.P.S., Neerdaels, C., Negrin, T., Ramakrishnan, R., Silberstein, A., Srivastava, U., Stata, R.: Building a cloud for Yahoo! IEEE Data Eng. Bull. 32, 36â43 (2009)DeCandia, G., Hastorun, D., Jampani, M., Kakulapati, G., Lakshman, A., Pilchin, A., Sivasubramanian, S., Vosshall, P., Vogels, W.: Dynamo: Amazonâs highly available key-value store. In: 21st ACM Symp. on Operat. Syst. Princ. (SOSP), Stevenson, Washington, USA, pp. 205â220 (2007)Stonebraker, M., Madden, S., Abadi, D.J., Harizopoulos, S., Hachem, N., Helland, P.: The end of an architectural era (itâs time for a complete rewrite). In: 33rd Intnl. Conf. on Very Large Data Bases (VLDB), pp. 1150â1160. ACM Press, Vienna (2007)Lomet, D.B., Fekete, A., Weikum, G., Zwilling, M.J.: Unbundling transaction services in the cloud. In: 4th Biennial Conf. on Innov. Data Syst. Research (CIDR), Asilomar, CA, USA (2009)Campbell, D.G., Kakivaya, G., Ellis, N.: Extreme scale with full SQL language support in Microsoft SQL Azure. In: Intnl. Conf. on Mngmnt. of Data (SIGMOD), pp. 1021â1024. ACM, New York (2010)Levandoski, J.J., Lomet, D., Mokbel, M.F., Zhao, K.K.: Deuteronomy: Transaction support for cloud data. In: 5th Biennial Conf. on Innov. Data Syst. Research (CIDR), Asilomar, CA, USA, pp. 123â133 (2011)Helland, P., Campbell, D.: Building on quicksand. In: 4th Biennial Conf. on Innov. Data Syst. Research (CIDR), Asilomar, CA, USA (2009)Muñoz-EscoĂ, F.D., GarcĂa-EscrivĂĄ, J.R., PallardĂł-Lozoya, M.R., Esparza-Peidro, J.: Managing scalable persistent data. Technical Report ITI-SIDI-2011/003, Instituto TecnolĂłgico de InformĂĄtica, Universitat PolitĂšcnica de ValĂšncia, Spain (2011)Agrawal, D., El Abbadi, A., Antony, S., Das, S.: Data management challenges in cloud computing infrastructures. In: 6th Intnl. Wshop. on Databases in Networked Information Systems (DNIS), Aizu-Wakamatsu, Japan, pp. 1â10 (2010)Stonebraker, M.: The case for shared nothing. IEEE Database Eng. Bull. 9, 4â9 (1986)Alonso, G., Kossmann, D., Roscoe, T.: SwissBox: An architecture for data processing appliances. In: 5th Biennial Conf. on Innov. Data Syst. Research (CIDR), Asilomar, CA, USA, pp. 32â37 (2011)Baker, J., Bond, C., Corbett, J.C., Furman, J.J., Khorlin, A., Larson, J., LĂ©on, J.M., Li, Y., Lloyd, A., Yushprakh, V.: Megastore: Providing scalable, highly available storage for interactive services. In: 5th Biennial Conf. on Innov. Data Syst. Research (CIDR), Asilomar, CA, USA, pp. 223â234 (2011)Curino, C., Jones, E.P.C., Popa, R.A., Malviya, N., Wu, E., Madden, S., Balakrishnan, H., Zeldovich, N.: Relational cloud: A database-as-a-service for the cloud. In: 5th Biennial Conf. on Innov. Data Syst. Research (CIDR), Asilomar, CA, USA, pp. 235â240 (2011)Das, S., Agrawal, D., El Abbadi, A.: ElasTraS: An elastic transactional data store in the cloud. CoRR abs/1008.3751 (2010)Vogels, W.: Eventually consistent. Commun. 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Research (CIDR), Asilomar, CA, USA, pp. 1â8 (2011)Microsoft Corp.: Windows Azure: Microsoftâs cloud services platform (2011), http://www.microsoft.com/windowsazure/VoltDB, Inc.: VoltDB technical overview: Next generation open-source SQL database with ACID for fast-scaling OLTP applications (2010), Downloadable from: http://voltdb.com/_pdf/VoltDBTechnicalOverviewWhitePaper.pd
Consistency in scalable systems
[EN] While eventual consistency is the general consistency guarantee ensured in cloud environments, stronger guarantees are in fact achievable. We show how scalable and highly available systems can provide processor, causal, sequential and session consistency during normal functioning. Failures and network partitions negatively affect consistency and generate divergence. After the failure or the partition, reconciliation techniques allow the system to restore consistency.This work has been supported by EU FEDER and Spanish MICINN under research grants TIN2009-14460-C03-01 and TIN2010-17193.Ruiz Fuertes, MI.; PallardĂł Lozoya, MR.; Muñoz-EscoĂ, FD. (2012). Consistency in scalable systems. En On the Move to Meaningful Internet Systems: OTM 2012. Springer Verlag (Germany). 7566:549-565. https://doi.org/10.1007/978-3-642-33615-7_7S5495657566Ahamad, M., Bazzi, R.A., John, R., Kohli, P., Neiger, G.: The power of processor consistency. 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Knowl. Data En. 17(4), 551â566 (2005
CHecklist for statistical Assessment of Medical Papers: the CHAMP statement
Misuse of statistics in medical and sports science research is common and may lead to detrimental consequences to healthcare. Many authors, editors and peer reviewers of medical papers will not have expert knowledge of statistics or may be unconvinced about the importance of applying correct statistics in medical research. Although there are guidelines on reporting statistics in medical papers, a checklist on the more general and commonly seen aspects of statistics to assess when peer-reviewing an article is needed. In this article, we propose a CHecklist for statistical Assessment of Medical Papers (CHAMP) comprising 30 items related to the design and conduct, data analysis, reporting and presentation, and interpretation of a research paper. While CHAMP is primarily aimed at editors and peer reviewers during the statistical assessment of a medical paper, we believe it will serve as a useful reference to improve authorsâ and readersâ practice in their use of statistics in medical research. We strongly encourage editors and peer reviewers to consult CHAMP when assessing manuscripts for potential publication. Authors also may apply CHAMP to ensure the validity of their statistical approach and reporting of medical research, and readers may consider using CHAMP to enhance their statistical assessment of a paper
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