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Andreas Pfeiffer

Bio: Andreas Pfeiffer is an academic researcher from CERN. The author has contributed to research in topics: Large Hadron Collider & Lepton. The author has an hindex of 149, co-authored 1756 publications receiving 131080 citations. Previous affiliations of Andreas Pfeiffer include Heidelberg University & Paul Scherrer Institute.


Papers
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Albert M. Sirunyan1, Armen Tumasyan1, Wolfgang Adam, Ece Aşılar  +2194 moreInstitutions (157)
TL;DR: In this article, a statistical combination of searches is presented for massive resonances decaying to WW, WZ, ZZ, WH, and ZH boson pairs in proton-proton collision data collected by the CMS experiment at the LHC.

43 citations

Journal ArticleDOI
TL;DR: In this article, the authors investigated whether circulating transforming growth factor beta 1 (TGF-beta1) and tumor necrosis factor alpha (TNF-alpha) are associated with diabetic kidney disease.
Abstract: Recent data have suggested that certain growth factors and cytokines are involved in the development of diabetic nephropathy The aim of this study was to investigate whether circulating transforming growth factor beta 1 (TGF-beta1) and tumor necrosis factor alpha (TNF-alpha) are associated with diabetic kidney disease Serum levels of active and total TGF-beta1 and TNF-alpha were measured in type 2 diabetic patients with nephropathy (n = 23) or without (n = 35) and normoglycemic controls (n = 12) Serum levels of circulating active TGF-beta1 were significantly higher in patients with diabetic nephropathy (043 +/- 006 ng x mL(-1)) compared with diabetic patients without renal involvement (023 +/- 003 ng x mL(-1), P = 002) and healthy controls (024 +/- 003 ng x mL(-1), P= 001), whereas the levels of total (active + latent) TGF-beta1 were not different between the subgroups Active TGF-beta1 concentrations were correlated with urinary albumin excretion (r = 49, P < 003) and serum creatinine (r= 55, P < 01) Sera from patients with type 2 diabetes contained significantly more TNF-alpha than sera from normoglycemic controls (307 +/- 024 v 165 +/- 020 pg x mL(-1), P = 001) However, the comparison of serum TNF-alpha concentrations between microalbuminuric and normoalbuminuric diabetic patients showed no significant difference (321 +/- 028 v 297 +/- 034 pg x mL(-1), P = 12) In conclusion, type 2 diabetic patients with diabetic nephropathy exhibit increased activation of TGF-beta1, in serum, suggesting an association between circulating TGF-beta1 activity and the development of renal disease

43 citations

Journal ArticleDOI
S. Chatrchyan1, Vardan Khachatryan1, Albert M. Sirunyan1, Armen Tumasyan1  +3952 moreInstitutions (145)
TL;DR: In this paper, the authors studied the characteristics of multi-particle production in proton-proton collisions at 7 TeV and compared the predictions of the PYTHIA and HERWIG event generators.
Abstract: Characteristics of multi-particle production in proton-proton collisions at sqrt(s) = 7 TeV are studied as a function of the charged-particle multiplicity, N[ch]. The produced particles are separated into two classes: those belonging to jets and those belonging to the underlying event. Charged particles are measured with pseudorapidity abs(eta) 0.25 GeV. Jets are reconstructed from charged-particles only and required to have pt > 5 GeV. The distributions of jet pt, average pt of charged particles belonging to the underlying event or to jets, jet rates, and jet shapes are presented as functions of N[ch] and compared to the predictions of the PYTHIA and HERWIG event generators. Predictions without multi-parton interactions fail completely to describe the N[ch]-dependence observed in the data. For increasing N[ch], PYTHIA systematically predicts higher jet rates and harder pt spectra than seen in the data, whereas HERWIG shows the opposite trends. At the highest multiplicity, the data--model agreement is worse for most observables, indicating the need for further tuning and/or new model ingredients.

43 citations

Journal ArticleDOI
Albert M. Sirunyan1, Armen Tumasyan1, Wolfgang Adam, Ece Aşılar  +2171 moreInstitutions (150)
TL;DR: This analysis is the first to perform a statistical combination of searches for dark matter produced with different heavy-flavor final states and provides exclusions that are stronger than those achieved with individual heavy- Flavour final states.
Abstract: A search is presented for an excess of events with heavy-flavor quark pairs ( ${t}\overline{{t}} $ and ${b} \overline{{b}} $ ) and a large imbalance in transverse momentum in data from proton–proton collisions at a center-of-mass energy of 13 $\,\text{TeV}$ . The data correspond to an integrated luminosity of 2.2 $\,\text{fb}^{-1}$ collected with the CMS detector at the CERN LHC. No deviations are observed with respect to standard model predictions. The results are used in the first interpretation of dark matter production in ${t}\overline{{t}} $ and ${b} \overline{{b}} $ final states in a simplified model. This analysis is also the first to perform a statistical combination of searches for dark matter produced with different heavy-flavor final states. The combination provides exclusions that are stronger than those achieved with individual heavy-flavor final states.

43 citations

Journal ArticleDOI
Albert M. Sirunyan1, Robin Erbacher2, Wagner Carvalho3, Maciej Górski  +2364 moreInstitutions (190)
TL;DR: In this paper, a search for the decays of heavy exotic long-lived particles (LLPs) that are produced in proton-proton collisions at a center-of-mass energy of 13 TeV at the CERN LHC and come to rest in the CMS detector is presented.
Abstract: A search is presented for the decays of heavy exotic long-lived particles (LLPs) that are produced in proton-proton collisions at a center-of-mass energy of 13 TeV at the CERN LHC and come to rest in the CMS detector. Their decays would be visible during periods of time well separated from proton-proton collisions. Two decay scenarios of stopped LLPs are explored: a hadronic decay detected in the calorimeter and a decay into muons detected in the muon system. The calorimeter (muon) search covers a period of sensitivity totaling 721 (744) hours in 38.6 (39.0) fb−1 of data collected by the CMS detector in 2015 and 2016. The results are interpreted in several scenarios that predict LLPs. Production cross section limits are set as a function of the mean proper lifetime and the mass of the LLPs, for lifetimes between 100 ns and 10 days. These are the most stringent limits to date on the mass of hadronically decaying stopped LLPs, and this is the first search at the LHC for stopped LLPs that decay to muons.

43 citations


Cited by
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[...]

08 Dec 2001-BMJ
TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

33,785 citations

Journal ArticleDOI
01 Apr 1988-Nature
TL;DR: In this paper, a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) is presented.
Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

9,929 citations

01 Jan 2014
TL;DR: These standards of care are intended to provide clinicians, patients, researchers, payors, and other interested individuals with the components of diabetes care, treatment goals, and tools to evaluate the quality of care.
Abstract: XI. STRATEGIES FOR IMPROVING DIABETES CARE D iabetes is a chronic illness that requires continuing medical care and patient self-management education to prevent acute complications and to reduce the risk of long-term complications. Diabetes care is complex and requires that many issues, beyond glycemic control, be addressed. A large body of evidence exists that supports a range of interventions to improve diabetes outcomes. These standards of care are intended to provide clinicians, patients, researchers, payors, and other interested individuals with the components of diabetes care, treatment goals, and tools to evaluate the quality of care. While individual preferences, comorbidities, and other patient factors may require modification of goals, targets that are desirable for most patients with diabetes are provided. These standards are not intended to preclude more extensive evaluation and management of the patient by other specialists as needed. For more detailed information, refer to Bode (Ed.): Medical Management of Type 1 Diabetes (1), Burant (Ed): Medical Management of Type 2 Diabetes (2), and Klingensmith (Ed): Intensive Diabetes Management (3). The recommendations included are diagnostic and therapeutic actions that are known or believed to favorably affect health outcomes of patients with diabetes. A grading system (Table 1), developed by the American Diabetes Association (ADA) and modeled after existing methods, was utilized to clarify and codify the evidence that forms the basis for the recommendations. The level of evidence that supports each recommendation is listed after each recommendation using the letters A, B, C, or E.

9,618 citations

Journal ArticleDOI
Georges Aad1, T. Abajyan2, Brad Abbott3, Jalal Abdallah4  +2964 moreInstitutions (200)
TL;DR: In this article, a search for the Standard Model Higgs boson in proton-proton collisions with the ATLAS detector at the LHC is presented, which has a significance of 5.9 standard deviations, corresponding to a background fluctuation probability of 1.7×10−9.

9,282 citations