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71.
Aad G Abbott B Abdallah J Abdel Khalek S Abdelalim AA Abdesselam A Abdinov O Abi B Abolins M Abouzeid OS Abramowicz H Abreu H Acerbi E Acharya BS Adamczyk L Adams DL Addy TN Adelman J Aderholz M Adomeit S Adragna P Adye T Aefsky S Aguilar-Saavedra JA Aharrouche M Ahlen SP Ahles F Ahmad A Ahsan M Aielli G Akdogan T Akesson TP Akimoto G Akimov AV Akiyama A Alam MS Alam MA Albert J Albrand S Aleksa M Aleksandrov IN Alessandria F Alexa C Alexander G Alexandre G Alexopoulos T Alhroob M Aliev M 《Physical review letters》2012,108(11):111803
A search for the standard model Higgs boson is performed in the diphoton decay channel. The data used correspond to an integrated luminosity of 4.9 fb(-1) collected with the ATLAS detector at the Large Hadron Collider in proton-proton collisions at a center-of-mass energy of √s=7 TeV. In the diphoton mass range 110-150 GeV, the largest excess with respect to the background-only hypothesis is observed at 126.5 GeV, with a local significance of 2.8 standard deviations. Taking the look-elsewhere effect into account in the range 110-150 GeV, this significance becomes 1.5 standard deviations. The standard model Higgs boson is excluded at 95% confidence level in the mass ranges of 113-115 GeV and 134.5-136 GeV. 相似文献
72.
Aad G Abbott B Abdallah J Abdelalim AA Abdesselam A Abdinov O Abi B Abolins M AbouZeid OS Abramowicz H Abreu H Acerbi E Acharya BS Adamczyk L Adams DL Addy TN Adelman J Aderholz M Adomeit S Adragna P Adye T Aefsky S Aguilar-Saavedra JA Aharrouche M Ahlen SP Ahles F Ahmad A Ahsan M Aielli G Akdogan T Åkesson TP Akimoto G Akimov AV Akiyama A Alam MS Alam MA Albert J Albrand S Aleksa M Aleksandrov IN Alessandria F Alexa C Alexander G Alexandre G Alexopoulos T Alhroob M Aliev M Alimonti G Alison J 《Physical review letters》2012,108(18):181802
The results of a search for pair production of the scalar partners of bottom quarks in 2.05 fb(-1) of pp collisions at sqrt[s]=7 TeV using the ATLAS experiment are reported. Scalar bottom quarks are searched for in events with large missing transverse momentum and two jets in the final state, where both jets are identified as originating from a bottom quark. In an R-parity conserving minimal supersymmetric scenario, assuming that the scalar bottom quark decays exclusively into a bottom quark and a neutralino, 95% confidence-level upper limits are obtained in the b(1) - χ(1)(0) mass plane such that for neutralino masses below 60 GeV scalar bottom masses up to 390 GeV are excluded. 相似文献
73.
Gunnar Brinkmalm Erik Portelius Annika Öhrfelt Niklas Mattsson Rita Persson Mikael K. Gustavsson Charles H. Vite Johan Gobom Jan‐Eric Månsson Jonas Nilsson Adnan Halim Göran Larson Ulla Rüetschi Henrik Zetterberg Kaj Blennow Ann Brinkmalm 《Journal of mass spectrometry : JMS》2012,47(5):591-603
Amyloid precursor protein (APP) is the precursor protein to amyloid β (Aβ), the main constituent of senile plaques in Alzheimer's disease (AD). Endogenous Aβ peptides reflect the APP processing, and greater knowledge of different APP degradation pathways is important to understand the mechanism underlying AD pathology. When one analyzes longer Aβ peptides by low‐energy collision‐induced dissociation tandem mass spectrometry (MS/MS), mainly long b‐fragments are observed, limiting the possibility to determine variations such as amino acid variants or post‐translational modifications (PTMs) within the N‐terminal half of the peptide. However, by using electron capture dissociation (ECD), we obtained a more comprehensive sequence coverage for several APP/Aβ peptide species, thus enabling a deeper characterization of possible variants and PTMs. Abnormal APP/Aβ processing has also been described in the lysosomal storage disease Niemann–Pick type C and the major large animal used for studying this disease is cat. By ECD MS/MS, a substitution of Asp7 → Glu in cat Aβ was identified. Further, sialylated core 1 like O‐glycans at Tyr10, recently discovered in human Aβ (a previously unknown glycosylation type), were identified also in cat cerebrospinal fluid (CSF). It is therefore likely that this unusual type of glycosylation is common for (at least) species belonging to the magnorder Boreoeutheria. We here describe a detailed characterization of endogenous APP/Aβ peptide species in CSF by using an online top‐down MS‐based method. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
74.
Rahul Varshney Najmussehar M. J. Ahsan 《Mathematical Methods of Operations Research》2012,75(2):185-197
In a multivariate stratified sampling more than one characteristic are defined on every unit of the population. An optimum
allocation which is optimum for one characteristic will generally be far from optimum for others. A compromise criterion is
needed to work out a usable allocation which is optimum, in some sense, for all the characteristics. When auxiliary information
is also available the precision of the estimates of the parameters can be increased by using it. Furthermore, if the travel
cost within the strata to approach the units selected in the sample is significant the cost function remains no more linear.
In this paper an attempt has been made to obtain a compromise allocation based on minimization of individual coefficients
of variation of the estimates of various characteristics, using auxiliary information and a nonlinear cost function with fixed
budget. A new compromise criterion is suggested. The problem is formulated as a multiobjective all integer nonlinear programming
problem. A solution procedure is also developed using goal programming technique. 相似文献
75.
Mufarreh Asmari Muhammad Waqas Adel Ehab Ibrahim Sobia Ahsan Halim Ajmal Khan Ahmed Al-Harrasi Hermann Wtzig Sami El Deeb 《Molecules (Basel, Switzerland)》2022,27(14)
The microscale thermophoresis (MST) technique was utilized to investigate lactoferrin–drug interaction with the iron chelator, deferiprone, using label-free system. MST depends on the intrinsic fluorescence of one interacting partner. The results indicated a significant interaction between lactoferrin and deferiprone. The estimated binding constant for the lactoferrin–deferiprone interaction was 8.9 × 10−6 ± 1.6, SD, which is to be reported for the first time. Such significant binding between lactoferrin and deferiprone may indicate the potentiation of the drug secretion into a lactating mother’s milk. The technique showed a fast and simple approach to study protein–drug interaction while avoiding complicated labeling procedures. Moreover, the binding behavior of deferiprone within the binding sites of lactoferrin was investigated through molecular docking which reflected that deferiprone mediates strong hydrogen bonding with ARG121 and ASP297 in pocket 1 and forms H-bond and ionic interaction with ASN640 and ASP395, respectively, in pocket 2 of lactoferrin. Meanwhile, iron ions provide ionic interaction with deferiprone in both of the pockets. The molecular dynamic simulation further confirmed that the binding of deferiprone with lactoferrin brings conformational changes in lactoferrin that is more energetically stable. It also confirmed that deferiprone causes positive correlation motion in the interacting residues of both pockets, with strong negative correlation motion in the loop regions, and thus changes the dynamics of lactoferrin. The MM-GBSA based binding free energy calculation revealed that deferiprone exhibits ∆G TOTAL of −63,163 kcal/mol in pocket 1 and −63,073 kcal/mol in pocket 2 with complex receptor–ligand difference in pocket 1 and pocket 2 of −117.38 kcal/mol and −111.54 kcal/mol, respectively, which in turn suggests that deferiprone binds more strongly in the pocket 1. The free energy landscape of the lactoferrin–deferiprone complex also showed that this complex remains in a high energy state that confirms the strong binding of deferiprone with the lactoferrin. The current research concluded that iron-chelating drugs (deferiprone) can be transported from the mother to the infant in the milk because of the strong attachment with the lactoferrin active pockets. 相似文献
76.
Karki Surya B. Gupta Tripti Thapa Yildirim-Ayan Eda Eisenmann Kathryn M. Ayan Halim 《Plasma Chemistry and Plasma Processing》2020,40(1):99-117
Plasma Chemistry and Plasma Processing - Non-thermal plasma has been a promising new cancer treatment modality in plasma oncology field. It generates extracellular and intracellular reactive... 相似文献
77.
W. K. Dawson C. H. Halim S. P. Weathersby J. A. Flint J. C. Lam T. J. Hoffman C. Boekema KC. B. Chan R. L. Lichti D. W. Cooke M. S. Jahan J. E. Crow 《Hyperfine Interactions》1991,63(1-4):219-226
Key results of zero-field (ZF) and transverse-field (TF) muon-spin-relaxation (μSR) experiments on superconducting and insulating
RBa2Cu3O
y
(R123
y
, with R=Eu, Gd, Pr and Pr/Y:y=6, 7) are examined. The chemical behavior of the positive muon probe is addressed, and muon-oxygen bonding is shown to occur
in all these cuprates. To explain magnetic fields at muon-probe sites in Pr
x
Y1−x
Ba2Cu3O
y
(0<=x<0.5,y=7 andx=0,y=6) samples, improvements on the reported magnetic structures from neutron diffraction are necessary. Cu magnetism in Pr123y (y=6,7) is observed belowT
N1, which is near RT. The magnetism seen belowT
N2 can be interpreted assuming an additional ordering in the Cutt-O chain layers. Alternatively, Pr ordering is also considered
as the cause of the second phase transition. Considering the specific muon-probe location, a more detailed interpretation
can be provided for the μSR parameters, measured in the normal and mixed states of these unconventional superconductors. 相似文献
78.
Abstract— The characteristic near-infrared emission band of O2 (1 Δg ) at 1.28 μ m has been recorded from carbon tetrachloride solutions of the 1, 4-endoperoxides of 1,4-dimethyInaphthalene and 1, 4-dimethoxy-9.10-diphenylanthracene undergoing thermal decomposition. 相似文献
79.
80.