Chemical and spectroscopic characterization of humic acids extracted from the bottom sediments of a Brazilian subtropical microbasin

International audienceHumic substances (HS) perform a fundamental role in aquatic environments, exhibiting different levels of reactivity in retaining metal ions and organic pollutants. Also, they control the primary production of these ecosystems and act in the carbon sequestering process. In order to improve our understanding vis-à-vis the structural and functional features of HS from aquatic systems, this study aimed to chemically and spectroscopically characterize humic acids (HA) isolated from bottom sediment samples of a stream in a Brazilian subtropical microbasin by elemental analysis, and infrared (FT-IR), ultraviolet and visible (UV-Vis) and solid-state 13C nuclear magnetic resonance (CP-MAS 13C NMR) spectroscopies, thermogravimetry (TG), and scanning electron microscopy (SEM). Although all samples originated from the same environment, the data showed that the HA have distinct chemical and spectroscopic properties, and that the location and characteristics of the sampling points from which the sediments were collected played an important role in the differences observed. Furthermore, vascular plant matter is probably the main contributor to these samples

Large atom number dual-species magneto-optical trap for fermionic 6Li and 40K atoms

We present the design, implementation and characterization of a dual-species magneto-optical trap (MOT) for fermionic 6Li and 40K atoms with large atom numbers. The MOT simultaneously contains 5.2x10^9 6Li-atoms and 8.0x10^9 40K-atoms, which are continuously loaded by a Zeeman slower for 6Li and a 2D-MOT for 40K. The atom sources induce capture rates of 1.2x10^9 6Li-atoms/s and 1.4x10^9 40K-atoms/s. Trap losses due to light-induced interspecies collisions of ~65% were observed and could be minimized to ~10% by using low magnetic field gradients and low light powers in the repumping light of both atomic species. The described system represents the starting point for the production of a large-atom number quantum degenerate Fermi-Fermi mixture

Measurement of D*+/- meson production in jets from pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

This paper reports a measurement of D*+/- meson production in jets from proton-proton collisions at a center-of-mass energy of sqrt(s) = 7 TeV at the CERN Large Hadron Collider. The measurement is based on a data sample recorded with the ATLAS detector with an integrated luminosity of 0.30 pb^-1 for jets with transverse momentum between 25 and 70 GeV in the pseudorapidity range |eta| < 2.5. D*+/- mesons found in jets are fully reconstructed in the decay chain: D*+ -> D0pi+, D0 -> K-pi+, and its charge conjugate. The production rate is found to be N(D*+/-)/N(jet) = 0.025 +/- 0.001(stat.) +/- 0.004(syst.) for D*+/- mesons that carry a fraction z of the jet momentum in the range 0.3 < z < 1. Monte Carlo predictions fail to describe the data at small values of z, and this is most marked at low jet transverse momentum.Comment: 10 pages plus author list (22 pages total), 5 figures, 1 table, matches published version in Physical Review

Behavioral Analysis Of Malicious Code Through Network Traffic And System Call Monitoring

Malicious code (malware) that spreads through the Internet-such as viruses, worms and trojans-is a major threat to information security nowadays and a profitable business for criminals. There are several approaches to analyze malware by monitoring its actions while it is running in a controlled environment, which helps to identify malicious behaviors. In this article we propose a tool to analyze malware behavior in a non-intrusive and effective way, extending the analysis possibilities to cover malware samples that bypass current approaches and also fixes some issues with these approaches. © 2011 SPIE.8059The Society of Photo-Optical Instrumentation Engineers (SPIE)Balzarotti, D., Cova, M., Karlberger, C., Kruegel, C., Kirda, E., Vigna, G., Efficient detection of split personalities in malware (2010) 17th Annual Network and Distributed System Security SymposiumBayer, U., Habibi, I., Balzarotti, D., Kirda, E., Kruegel, C., A view on current malware behaviors (2009) Usenix Workshop on Large-scale Exploits and Emergent Threats (LEET)Bayer, U., Kruegel, C., Kirda, E., TTanalyze: A tool for analyzing malware (2006) Proc. 15th Ann. Conf. European Inst. for Computer Antivirus Research (EICAR), pp. 180-192Bellard, F., QEMU, a fast and portable dynamic translator (2005) Proc. of the Annual Conference on USENIX Annual Technical Conference, pp. 41-41. , USENIX AssociationBinsalleeh, H., Ormerod, T., Boukhtouta, A., Sinha, P., Youssef, A., Debbabi, M., Wang, L., On the analysis of the zeus botnet crimeware toolkit (2010) Proc. of the Eighth Annual Conference on Privacy, Security and Trust, PST'2010Blunden, B., (2009) The Rootkit Arsenal: Escape and Evasion in the Dark Corners of the System, , Jones and Bartlett Publishers, Inc, 1th editionChoi, Y., Kim, I., Oh, J., Ryou, J., PE file header analysis-based packed pe file detection technique (PHAD) (2008) Proc of the International Symposium on Computer Science and Its Applications, pp. 28-31Dinaburg, A., Royal, P., Sharif, M., Lee, W., Ether: Malware analysis via hardware virtualization extensions (2008) Proc. Proceedings of the 15th ACM Conference on Computer and Communications Security (CCS 2008), , OctoberFather, H., Hooking windows API-technics of hooking API functions on windows (2004) CodeBreakers J., 1 (2)Franklin, J., Paxson, V., Perrig, A., Savage, S., An inquiry into the nature and causes of the wealth of internet miscreants (2007) Conference on Computer and Communications Security (CCS)Garfinkel, T., Rosenblum, M., A virtual machine introspection based architecture for intrusion detection (2003) Proc. Network and Distributed Systems Security Symposium, pp. 191-206Hoglund, G., Butler, J., (2005) Rootkits: Subverting the Windows Kernel, , Addison- Wesley Professional, 1th editionHolz, T., Engelberth, M., Freiling, F., Learning more about the underground economy: A case-study of keyloggers and dropzones (2008) Reihe Informatik TR-2008-006, , University of Mannheimhttp://www.joebox.org/Kang, M.G., Poosankam, P., Yin, H., Renovo: A hidden code extractor for packed exe-cutables (2007) Proc. of the 2007 ACM Workshop on Recurring Malcode (WORM 2007)Kong, J., (2007) Designing BSD Rootkits, , No Starch Press, 1th editionLeder, F., Werner, T., Know your enemy: Containing conficker (2009) The Honeynet Project & Research AllianceMartignoni, L., Christodorescu, M., Jha, S., Omniunpack: Fast, generic, and safe unpack-ing of malware (2007) Proc. of the Annual Computer Security Applications Conference (ACSAC)http://download.microsoft.com/download/9/c/5/9c5b2167-8017-4bae-9fde- d599bac8184a/pecoff_v8.docxMoser, A., Kruegel, C., Kirda, E., Limits of static analysis for malware detection (2007) ACSAC, pp. 421-430. , IEEE Computer Societyhttp://www.securelist.com/en/descriptions/old145521http://www.softpanorama.org/Malware/Malware_defense_history/ Malware_gallery/Network_worms/allaple_rahack.shtmlSong, D., Brumley, D., Yin, H., Caballero, J., Jager, I., Kang, M.G., Liang, Z., Saxena, P., BitBlaze: A new approach to computer security via binary analysis (2008) Proc. of the 4th International Conference on Information Systems SecurityWillems, G., Holz, T., Freiling, F., Toward automated dynamic malware analysis using CWSandbox (2007) IEEE Security and Privacy, 5 (2), pp. 32-39. , DOI 10.1109/MSP.2007.45Yegneswaran, V., Saidi, H., Porras, P., Eureka: A framework for enabling static analysis on malware (2008) Technical Report SRI-CSL-08-01 Computer Science Laboratory and College of Computing, , Georgia Institute of Technolog

Search for supersymmetry in final states with jets, missing transverse momentum and one isolated lepton in sqrt{s} = 7 TeV pp collisions using 1 fb-1 of ATLAS data

We present an update of a search for supersymmetry in final states containing jets, missing transverse momentum, and one isolated electron or muon, using 1.04 fb^-1 of proton-proton collision data at sqrt{s} = 7 TeV recorded by the ATLAS experiment at the LHC in the first half of 2011. The analysis is carried out in four distinct signal regions with either three or four jets and variations on the (missing) transverse momentum cuts, resulting in optimized limits for various supersymmetry models. No excess above the standard model background expectation is observed. Limits are set on the visible cross-section of new physics within the kinematic requirements of the search. The results are interpreted as limits on the parameters of the minimal supergravity framework, limits on cross-sections of simplified models with specific squark and gluino decay modes, and limits on parameters of a model with bilinear R-parity violation.Comment: 18 pages plus author list (30 pages total), 9 figures, 4 tables, final version to appear in Physical Review

Measurement of charm production at central rapidity in proton-proton collisions at s=2.76\sqrt{s} = 2.76 TeV

The $p_{\rm T}$-differential production cross sections of the prompt (B feed-down subtracted) charmed mesons D$^0$, D$^+$, and D$^{*+}$ in the rapidity range $|y|<0.5$, and for transverse momentum $1< p_{\rm T} <12$ GeV/$c$, were measured in proton-proton collisions at $\sqrt{s} = 2.76$ TeV with the ALICE detector at the Large Hadron Collider. The analysis exploited the hadronic decays D$^0 \rightarrow$K$\pi$, D$^+ \rightarrow$K$\pi\pi$, D$^{*+} \rightarrow$D$^0\pi$, and their charge conjugates, and was performed on a $L_{\rm int} = 1.1$ nb$^{-1}$ event sample collected in 2011 with a minimum-bias trigger. The total charm production cross section at $\sqrt{s} = 2.76$ TeV and at 7 TeV was evaluated by extrapolating to the full phase space the $p_{\rm T}$-differential production cross sections at $\sqrt{s} = 2.76$ TeV and our previous measurements at $\sqrt{s} = 7$ TeV. The results were compared to existing measurements and to perturbative-QCD calculations. The fraction of cdbar D mesons produced in a vector state was also determined.Comment: 20 pages, 5 captioned figures, 4 tables, authors from page 15, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/307

Reducing heterotic M-theory to five dimensional supergravity on a manifold with boundary

This paper constructs the reduction of heterotic $M$-theory in eleven dimensions to a supergravity model on a manifold with boundary in five dimensions using a Calabi-Yau three-fold. New results are presented for the boundary terms in the action and for the boundary conditions on the bulk fields. Some general features of dualisation on a manifold with boundary are used to explain the origin of some topological terms in the action. The effect of gaugino condensation on the fermion boundary conditions leads to a `twist' in the chirality of the gravitino which can provide an uplifting mechanism in the vacuum energy to cancel the cosmological constant after moduli stabilisation.Comment: 16 pages, RevTe

Particle-yield modification in jet-like azimuthal di-hadron correlations in Pb-Pb collisions at sNN\sqrt{s_{\rm NN}} = 2.76 TeV

The yield of charged particles associated with high-$p_{\rm T}$ trigger particles ($8 < p_{\rm T} < 15$ GeV/$c$) is measured with the ALICE detector in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV relative to proton-proton collisions at the same energy. The conditional per-trigger yields are extracted from the narrow jet-like correlation peaks in azimuthal di-hadron correlations. In the 5% most central collisions, we observe that the yield of associated charged particles with transverse momenta $p_{\rm T}> 3$ GeV/$c$ on the away-side drops to about 60% of that observed in pp collisions, while on the near-side a moderate enhancement of 20-30% is found.Comment: 15 pages, 2 captioned figures, 1 table, authors from page 10, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/350

Measurement of tau polarization in W->taunu decays with the ATLAS detector in pp collisions at sqrt(s) = 7 TeV

In this paper, a measurement of tau polarization in W->taunu decays is presented. It is measured from the energies of the decay products in hadronic tau decays with a single final state charged particle. The data, corresponding to an integrated luminosity of 24 pb^-1, were collected by the ATLAS experiment at the Large Hadron Collider in 2010. The measured value of the tau polarization is Ptau = -1.06 +/- 0.04 (stat) + 0.05 (syst) - 0.07 (syst), in agreement with the Standard Model prediction, and is consistent with a physically allowed 95% CL interval [-1,-0.91]. Measurements of tau polarization have not previously been made at hadron colliders.Comment: 10 pages plus author list (25 pages total), 4 figures, 4 tables, revised author list, matches published EPJC versio

Estudo coproparasitológico da espécie Cebus libidinosus (macaco-prego)

RESUMO Os estudos sobre parasitos gastrintestinais em primatas mantidos em cativeiros são importantes para o manejo da população de macacos e para a manutenção da saúde das pessoas que trabalham com esses animais, pois muitos desses parasitos são potentes causadores de zoonoses. Este trabalho objetivou estudar os parasitas presentes nas fezes da espécie Cebus libidinosus, criada em cativeiro. Foram utilizados 22 animais apreendidos pelo Ibama-PI, IbamA-PB e Cipama (Companhia Independente de Policiamento Ambiental do Piauí), no período de 2007 a 2009, que faziam parte do Projeto de Soltura Experimental em Ilhas Lacustres de Espécies do Gênero Cebus sp., do Ibama-PI. Foram encontrados parasitas do gênero Ancylostoma em 45% (10/22) das amostras e do gênero Strongyloides em 23% (05/22). No método de Willis (1921) e no método de Hoffman, o Ancylostoma sp. estava presente em 41% (09/22) e o Strongyloides sp. em 18% (04/22) das amostras. A coprocultura revelou a presença de larva do gênero Ancylostoma em 50% dos grupos estudados. A espécie Cebus libidinosus revelou-se parasitada por helmintos gastrintestinais dos gêneros Ancylostoma e Strongyloide.</jats:p