Luis Mendoza - Academia.edu (original) (raw)

Papers by Luis Mendoza

Research paper thumbnail of Towards a Common Public Service Infrastructure for Swiss Universities

Proceedings of the 11th International Conference on Enterprise Information, 2009

Due to the Bologna Declaration and the according procedures of performance management and output ... more Due to the Bologna Declaration and the according procedures of performance management and output funding universities are undergoing organisational changes both within and across the universities. The need for an appropriate organisational structure and for efficient and effective processes makes the support through a correspondent IT essential. The IT environment of Swiss universities is currently dominated by a high level of decentralisation and a high degree of proprietary solutions. Economies of scale through joint development or shared services remain untapped. Also the increasingly essential integration of applications to support either university-internal or cross-organizational processes is hindered. In this paper we propose an approach for a comprehensive service-oriented architecture for swiss universities to overcome the current situation and to cope with organizational and technical challenges. We further present an application scenario revealing how Swiss universities will benefit of the proposed architecture.

Research paper thumbnail of Measurements of the d0 experiment in diffractive physics

Research paper thumbnail of Measurement of the dijet invariant mass cross section in pp collisions at √s=1.96 TeV

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, 2010

Research paper thumbnail of Performance of the ATLAS detector using first collision data

Journal of High Energy Physics, 2010

More than half a million minimum-bias events of LHC collision data were collected by the ATLAS ex... more More than half a million minimum-bias events of LHC collision data were collected by the ATLAS experiment in December 2009 at centre-of-mass energies of 0.9 TeV and 2.36 TeV. This paper reports on studies of the initial performance of the ATLAS detector from these data. Comparisons between data and Monte Carlo predictions are shown for distributions of several track-and calorimeter-based quantities. The good performance of the ATLAS detector in these first data gives confidence for successful running at higher energies.

Research paper thumbnail of Search for squarks and gluinos in events with jets and missing transverse energy using 2.1 fb−1 of pp¯ collision data at s=1.96 TeV

Physics Letters B, 2008

A data sample corresponding to an integrated luminosity of 2.1 fb −1 collected by the DØ detector... more A data sample corresponding to an integrated luminosity of 2.1 fb −1 collected by the DØ detector at the Fermilab Tevatron Collider was analyzed to search for squarks and gluinos produced in pp collisions at a center-of-mass energy of 1.96 TeV. No evidence for the production of such particles was observed in topologies involving jets and missing transverse energy, and 95% C.L. lower limits of 379 GeV and 308 GeV were set on the squark and gluino masses, respectively, within the framework of minimal supergravity with tan β = 3, A 0 = 0, and μ < 0. The corresponding previous limits are improved by 54 GeV and 67 GeV.

Research paper thumbnail of Search for the Standard Model Higgs Boson in theZH→νν¯bb¯Channel in5.2  fb−1ofpp¯Collisions ats=1.96  TeV

Physical Review Letters, 2010

Research paper thumbnail of Combination of Tevatron Searches for the Standard Model Higgs Boson in theW+W−Decay Mode

Physical Review Letters, 2010

We combine searches by the CDF and D0 Collaborations for a Higgs boson decaying to W þ W À. The d... more We combine searches by the CDF and D0 Collaborations for a Higgs boson decaying to W þ W À. The data correspond to an integrated total luminosity of 4.8 (CDF) and 5.4 (D0) fb À1 of p p collisions at ffiffi ffi s p ¼ 1:96 TeV at the Fermilab Tevatron collider. No excess is observed above background expectation, and resulting limits on Higgs boson production exclude a standard model Higgs boson in the mass range 162-166 GeV at the 95% C.L.

Research paper thumbnail of Observation of a Centrality-Dependent Dijet Asymmetry in Lead-Lead Collisions atsNN=2.76  TeVwith the ATLAS Detector at the LHC

Physical Review Letters, 2010

Research paper thumbnail of Measurement of the Electron Charge Asymmetry inpp¯→W+X→eν+XEvents ats=1.96  TeV

Physical Review Letters, 2008

We present a measurement of the electron charge asymmetry in p " p ! W þ X ! e þ X events at a ce... more We present a measurement of the electron charge asymmetry in p " p ! W þ X ! e þ X events at a center of mass energy of 1.96 TeV using 0:75 fb À1 of data collected with the D0 detector at the Fermilab Tevatron Collider. The asymmetry is measured as a function of the electron transverse momentum and pseudorapidity in the interval (À3:2, 3.2) and is compared with expectations from next-to-leading order calculations in perturbative quantum chromodynamics. These measurements will allow more accurate determinations of the proton parton distribution functions.

Research paper thumbnail of Measurement ofBs0Mixing Parameters from the Flavor-Tagged DecayBs0→J/ψϕ

Physical Review Letters, 2008

From an analysis of the flavor-tagged decay B 0 s ! J=c we obtain the width difference between th... more From an analysis of the flavor-tagged decay B 0 s ! J=c we obtain the width difference between the B 0 s light and heavy mass eigenstates, ÁÀ s ¼ 0:19 AE 0:07ðstatÞ þ0:02 À0:01 ðsystÞ ps À1 , and the CP-violating phase, s ¼ À0:57 þ0:24 À0:30 ðstatÞ þ0:08 À0:02 ðsystÞ. The allowed 90% CL intervals of ÁÀ s and s are 0:06 < ÁÀ s < 0:30 ps À1 and À1:20 < s < 0:06, respectively. The data sample corresponds to an integrated luminosity of 2:8 fb À1 accumulated with the D0 detector at the Fermilab Tevatron collider.

Research paper thumbnail of Measurement of Top Quark Polarization in Top-Antitop Events from Proton-Proton Collisions ats=7  TeVUsing the ATLAS Detector

Physical Review Letters, 2013

Research paper thumbnail of Search for New Phenomena intt¯Events with Large Missing Transverse Momentum in Proton-Proton Collisions ats=7  TeVwith the ATLAS Detector

Physical Review Letters, 2012

A search for new phenomena in t " t events with large missing transverse momentum in proton-proto... more A search for new phenomena in t " t events with large missing transverse momentum in proton-proton collisions at a center-of-mass energy of 7 TeV is presented. The measurement is based on 1:04 fb À1 of data collected with the ATLAS detector at the LHC. Contributions to this final state may arise from a number of standard model extensions. The results are interpreted in terms of a model where new top-quark partners are pair produced and each decay to an on-shell top (or antitop) quark and a long-lived undetected neutral particle. The data are found to be consistent with standard model expectations. A limit at 95% confidence level is set excluding a cross section times branching ratio of 1.1 pb for a top-partner mass of 420 GeV and a neutral particle mass less than 10 GeV. In a model of exotic fourth generation quarks, toppartner masses are excluded up to 420 GeV and neutral particle masses up to 140 GeV.

Research paper thumbnail of Search for the Higgs Boson in theH→WW→lνjjDecay Channel inppCollisions ats=7  TeVwith the ATLAS Detector

Physical Review Letters, 2011

Research paper thumbnail of Search for a Standard Model Higgs Boson in theH→ZZ→ℓ+ℓ−νν¯Decay Channel with the ATLAS Detector

Physical Review Letters, 2011

Research paper thumbnail of Search for nonpointing photons in the diphoton andETmissfinal state ins=7  TeVproton-proton collisions using the ATLAS detector

Physical Review D, 2013

A search has been performed for photons originating in the decay of a neutral long-lived particle... more A search has been performed for photons originating in the decay of a neutral long-lived particle, exploiting the capabilities of the ATLAS electromagnetic calorimeter to make precise measurements of the flight direction of photons, as well as the calorimeter's excellent time resolution. The search has been made in the diphoton plus missing transverse energy final state, using the full data sample of 4:8 fb À1 of 7 TeV proton-proton collisions collected in 2011 with the ATLAS detector at the LHC. No excess is observed above the background expected from Standard Model processes. The results are used to set exclusion limits in the context of gauge mediated supersymmetry breaking models, with the lightest neutralino being the next-to-lightest supersymmetric particle and decaying with a lifetime in excess of 0.25 ns into a photon and a gravitino.

Research paper thumbnail of Measurement of theWboson mass

Physical Review D, 1998

We present a measurement of the W boson mass using data collected by the DØ experiment at the Fer... more We present a measurement of the W boson mass using data collected by the DØ experiment at the Fermilab Tevatron during 1994-1995. We identify W bosons by their decays to eν final states. We extract the W mass, MW , by fitting the transverse mass and transverse electron momentum spectra from a sample of 28,323 W → eν decay candidates. We use a sample of 3,563 dielectron events, mostly due to Z → ee decays, to constrain our model of the detector response. From the transverse mass fit we measure MW = 80.44 ± 0.10(stat) ± 0.07(syst) GeV. Combining this with our previously published result from data taken in 1992-1993, we obtain MW = 80.43 ± 0.11 GeV.

Research paper thumbnail of Search for stable hadronising squarks and gluinos with the ATLAS experiment at the LHC

Physics Letters B, 2011

Hitherto unobserved long-lived massive particles with electric and/or colour charge are predicted... more Hitherto unobserved long-lived massive particles with electric and/or colour charge are predicted by a range of theories which extend the Standard Model. In this Letter a search is performed at the ATLAS experiment for slow-moving charged particles produced in proton-proton collisions at 7 TeV centre-ofmass energy at the LHC, using a data-set corresponding to an integrated luminosity of 34 pb −1. No deviations from Standard Model expectations are found. This result is interpreted in a framework of supersymmetry models in which coloured sparticles can hadronise into long-lived bound hadronic states, termed R-hadrons, and 95% CL limits are set on the production cross-sections of squarks and gluinos. The influence of R-hadron interactions in matter was studied using a number of different models, and lower mass limits for stable sbottoms and stops are found to be 294 and 309 GeV respectively. The lower mass limit for a stable gluino lies in the range from 562 to 586 GeV depending on the model assumed. Each of these constraints is the most stringent to date.

Research paper thumbnail of An Efficient Method for Dynamic Analysis of Gene Regulatory Networks and in silico Gene Perturbation Experiments

Lecture Notes in Computer Science, 2007

With the increasing availability of experimental data on gene-gene and protein-protein interactio... more With the increasing availability of experimental data on gene-gene and protein-protein interactions, modeling of gene regulatory networks has gained a special attention lately. To have a better understanding of these networks it is necessary to capture their dynamical properties, by computing its steady states. Various methods have been proposed to compute steady states but almost all of them suffer from the state space explosion problem with the increasing size of the networks. Hence it becomes difficult to model even moderate sized networks using these techniques. In this paper, we present a new representation of gene regulatory networks, which facilitates the steady state computation of networks as large as 1200 nodes and 5000 edges. We benchmarked and validated our algorithm on the T helper model from [8] and performed in silico knock out experiments: showing both a reduction in computation time and correct steady state identification.

Research paper thumbnail of Interaction of the 530 Ribosomal Site With Regions of MRNA

Biosystems, 1998

We evaluated the energetic stability of all possible 10-base fragments of the small subunit (SS) ... more We evaluated the energetic stability of all possible 10-base fragments of the small subunit (SS) rRNA with a large ensemble of mRNAs. Results show that the 530 loop is the only conserved region that interacts favorably around the start codon as well as the elongation region of messengers. The interaction profile of the 530 loop around the stop codon showed that base pairing was energetically unfavorable in that region. With these results we constructed a simple scheme for the role of rRNA-mRNA interactions in the protein translation mechanism.

Research paper thumbnail of Towards a Common Public Service Infrastructure for Swiss Universities

Proceedings of the 11th International Conference on Enterprise Information, 2009

Due to the Bologna Declaration and the according procedures of performance management and output ... more Due to the Bologna Declaration and the according procedures of performance management and output funding universities are undergoing organisational changes both within and across the universities. The need for an appropriate organisational structure and for efficient and effective processes makes the support through a correspondent IT essential. The IT environment of Swiss universities is currently dominated by a high level of decentralisation and a high degree of proprietary solutions. Economies of scale through joint development or shared services remain untapped. Also the increasingly essential integration of applications to support either university-internal or cross-organizational processes is hindered. In this paper we propose an approach for a comprehensive service-oriented architecture for swiss universities to overcome the current situation and to cope with organizational and technical challenges. We further present an application scenario revealing how Swiss universities will benefit of the proposed architecture.

Research paper thumbnail of Measurements of the d0 experiment in diffractive physics

Research paper thumbnail of Measurement of the dijet invariant mass cross section in pp collisions at √s=1.96 TeV

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, 2010

Research paper thumbnail of Performance of the ATLAS detector using first collision data

Journal of High Energy Physics, 2010

More than half a million minimum-bias events of LHC collision data were collected by the ATLAS ex... more More than half a million minimum-bias events of LHC collision data were collected by the ATLAS experiment in December 2009 at centre-of-mass energies of 0.9 TeV and 2.36 TeV. This paper reports on studies of the initial performance of the ATLAS detector from these data. Comparisons between data and Monte Carlo predictions are shown for distributions of several track-and calorimeter-based quantities. The good performance of the ATLAS detector in these first data gives confidence for successful running at higher energies.

Research paper thumbnail of Search for squarks and gluinos in events with jets and missing transverse energy using 2.1 fb−1 of pp¯ collision data at s=1.96 TeV

Physics Letters B, 2008

A data sample corresponding to an integrated luminosity of 2.1 fb −1 collected by the DØ detector... more A data sample corresponding to an integrated luminosity of 2.1 fb −1 collected by the DØ detector at the Fermilab Tevatron Collider was analyzed to search for squarks and gluinos produced in pp collisions at a center-of-mass energy of 1.96 TeV. No evidence for the production of such particles was observed in topologies involving jets and missing transverse energy, and 95% C.L. lower limits of 379 GeV and 308 GeV were set on the squark and gluino masses, respectively, within the framework of minimal supergravity with tan β = 3, A 0 = 0, and μ < 0. The corresponding previous limits are improved by 54 GeV and 67 GeV.

Research paper thumbnail of Search for the Standard Model Higgs Boson in theZH→νν¯bb¯Channel in5.2  fb−1ofpp¯Collisions ats=1.96  TeV

Physical Review Letters, 2010

Research paper thumbnail of Combination of Tevatron Searches for the Standard Model Higgs Boson in theW+W−Decay Mode

Physical Review Letters, 2010

We combine searches by the CDF and D0 Collaborations for a Higgs boson decaying to W þ W À. The d... more We combine searches by the CDF and D0 Collaborations for a Higgs boson decaying to W þ W À. The data correspond to an integrated total luminosity of 4.8 (CDF) and 5.4 (D0) fb À1 of p p collisions at ffiffi ffi s p ¼ 1:96 TeV at the Fermilab Tevatron collider. No excess is observed above background expectation, and resulting limits on Higgs boson production exclude a standard model Higgs boson in the mass range 162-166 GeV at the 95% C.L.

Research paper thumbnail of Observation of a Centrality-Dependent Dijet Asymmetry in Lead-Lead Collisions atsNN=2.76  TeVwith the ATLAS Detector at the LHC

Physical Review Letters, 2010

Research paper thumbnail of Measurement of the Electron Charge Asymmetry inpp¯→W+X→eν+XEvents ats=1.96  TeV

Physical Review Letters, 2008

We present a measurement of the electron charge asymmetry in p " p ! W þ X ! e þ X events at a ce... more We present a measurement of the electron charge asymmetry in p " p ! W þ X ! e þ X events at a center of mass energy of 1.96 TeV using 0:75 fb À1 of data collected with the D0 detector at the Fermilab Tevatron Collider. The asymmetry is measured as a function of the electron transverse momentum and pseudorapidity in the interval (À3:2, 3.2) and is compared with expectations from next-to-leading order calculations in perturbative quantum chromodynamics. These measurements will allow more accurate determinations of the proton parton distribution functions.

Research paper thumbnail of Measurement ofBs0Mixing Parameters from the Flavor-Tagged DecayBs0→J/ψϕ

Physical Review Letters, 2008

From an analysis of the flavor-tagged decay B 0 s ! J=c we obtain the width difference between th... more From an analysis of the flavor-tagged decay B 0 s ! J=c we obtain the width difference between the B 0 s light and heavy mass eigenstates, ÁÀ s ¼ 0:19 AE 0:07ðstatÞ þ0:02 À0:01 ðsystÞ ps À1 , and the CP-violating phase, s ¼ À0:57 þ0:24 À0:30 ðstatÞ þ0:08 À0:02 ðsystÞ. The allowed 90% CL intervals of ÁÀ s and s are 0:06 < ÁÀ s < 0:30 ps À1 and À1:20 < s < 0:06, respectively. The data sample corresponds to an integrated luminosity of 2:8 fb À1 accumulated with the D0 detector at the Fermilab Tevatron collider.

Research paper thumbnail of Measurement of Top Quark Polarization in Top-Antitop Events from Proton-Proton Collisions ats=7  TeVUsing the ATLAS Detector

Physical Review Letters, 2013

Research paper thumbnail of Search for New Phenomena intt¯Events with Large Missing Transverse Momentum in Proton-Proton Collisions ats=7  TeVwith the ATLAS Detector

Physical Review Letters, 2012

A search for new phenomena in t " t events with large missing transverse momentum in proton-proto... more A search for new phenomena in t " t events with large missing transverse momentum in proton-proton collisions at a center-of-mass energy of 7 TeV is presented. The measurement is based on 1:04 fb À1 of data collected with the ATLAS detector at the LHC. Contributions to this final state may arise from a number of standard model extensions. The results are interpreted in terms of a model where new top-quark partners are pair produced and each decay to an on-shell top (or antitop) quark and a long-lived undetected neutral particle. The data are found to be consistent with standard model expectations. A limit at 95% confidence level is set excluding a cross section times branching ratio of 1.1 pb for a top-partner mass of 420 GeV and a neutral particle mass less than 10 GeV. In a model of exotic fourth generation quarks, toppartner masses are excluded up to 420 GeV and neutral particle masses up to 140 GeV.

Research paper thumbnail of Search for the Higgs Boson in theH→WW→lνjjDecay Channel inppCollisions ats=7  TeVwith the ATLAS Detector

Physical Review Letters, 2011

Research paper thumbnail of Search for a Standard Model Higgs Boson in theH→ZZ→ℓ+ℓ−νν¯Decay Channel with the ATLAS Detector

Physical Review Letters, 2011

Research paper thumbnail of Search for nonpointing photons in the diphoton andETmissfinal state ins=7  TeVproton-proton collisions using the ATLAS detector

Physical Review D, 2013

A search has been performed for photons originating in the decay of a neutral long-lived particle... more A search has been performed for photons originating in the decay of a neutral long-lived particle, exploiting the capabilities of the ATLAS electromagnetic calorimeter to make precise measurements of the flight direction of photons, as well as the calorimeter's excellent time resolution. The search has been made in the diphoton plus missing transverse energy final state, using the full data sample of 4:8 fb À1 of 7 TeV proton-proton collisions collected in 2011 with the ATLAS detector at the LHC. No excess is observed above the background expected from Standard Model processes. The results are used to set exclusion limits in the context of gauge mediated supersymmetry breaking models, with the lightest neutralino being the next-to-lightest supersymmetric particle and decaying with a lifetime in excess of 0.25 ns into a photon and a gravitino.

Research paper thumbnail of Measurement of theWboson mass

Physical Review D, 1998

We present a measurement of the W boson mass using data collected by the DØ experiment at the Fer... more We present a measurement of the W boson mass using data collected by the DØ experiment at the Fermilab Tevatron during 1994-1995. We identify W bosons by their decays to eν final states. We extract the W mass, MW , by fitting the transverse mass and transverse electron momentum spectra from a sample of 28,323 W → eν decay candidates. We use a sample of 3,563 dielectron events, mostly due to Z → ee decays, to constrain our model of the detector response. From the transverse mass fit we measure MW = 80.44 ± 0.10(stat) ± 0.07(syst) GeV. Combining this with our previously published result from data taken in 1992-1993, we obtain MW = 80.43 ± 0.11 GeV.

Research paper thumbnail of Search for stable hadronising squarks and gluinos with the ATLAS experiment at the LHC

Physics Letters B, 2011

Hitherto unobserved long-lived massive particles with electric and/or colour charge are predicted... more Hitherto unobserved long-lived massive particles with electric and/or colour charge are predicted by a range of theories which extend the Standard Model. In this Letter a search is performed at the ATLAS experiment for slow-moving charged particles produced in proton-proton collisions at 7 TeV centre-ofmass energy at the LHC, using a data-set corresponding to an integrated luminosity of 34 pb −1. No deviations from Standard Model expectations are found. This result is interpreted in a framework of supersymmetry models in which coloured sparticles can hadronise into long-lived bound hadronic states, termed R-hadrons, and 95% CL limits are set on the production cross-sections of squarks and gluinos. The influence of R-hadron interactions in matter was studied using a number of different models, and lower mass limits for stable sbottoms and stops are found to be 294 and 309 GeV respectively. The lower mass limit for a stable gluino lies in the range from 562 to 586 GeV depending on the model assumed. Each of these constraints is the most stringent to date.

Research paper thumbnail of An Efficient Method for Dynamic Analysis of Gene Regulatory Networks and in silico Gene Perturbation Experiments

Lecture Notes in Computer Science, 2007

With the increasing availability of experimental data on gene-gene and protein-protein interactio... more With the increasing availability of experimental data on gene-gene and protein-protein interactions, modeling of gene regulatory networks has gained a special attention lately. To have a better understanding of these networks it is necessary to capture their dynamical properties, by computing its steady states. Various methods have been proposed to compute steady states but almost all of them suffer from the state space explosion problem with the increasing size of the networks. Hence it becomes difficult to model even moderate sized networks using these techniques. In this paper, we present a new representation of gene regulatory networks, which facilitates the steady state computation of networks as large as 1200 nodes and 5000 edges. We benchmarked and validated our algorithm on the T helper model from [8] and performed in silico knock out experiments: showing both a reduction in computation time and correct steady state identification.

Research paper thumbnail of Interaction of the 530 Ribosomal Site With Regions of MRNA

Biosystems, 1998

We evaluated the energetic stability of all possible 10-base fragments of the small subunit (SS) ... more We evaluated the energetic stability of all possible 10-base fragments of the small subunit (SS) rRNA with a large ensemble of mRNAs. Results show that the 530 loop is the only conserved region that interacts favorably around the start codon as well as the elongation region of messengers. The interaction profile of the 530 loop around the stop codon showed that base pairing was energetically unfavorable in that region. With these results we constructed a simple scheme for the role of rRNA-mRNA interactions in the protein translation mechanism.