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1.
Mar Pollut Bull ; 178: 113554, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35390630

RESUMO

To inform risk assessments, reliable, time efficient and affordable quantification methods are required for creating a microplastic (MP) pollution baseline in the world's oceans. To facilitate this, MP abundance was investigated in sediments of three contrasting areas of the UK continental shelf: North West of Jones Bank, the Canyons in the Celtic Sea and Dogger Bank in the North Sea, utilising the Nile Red tagging method to assess its time efficiency and cost. Average MP abundance in the top 10 cm was 1050-2700 MP kg-1. MP abundance decreased with increasing sediment depth and increased with increasing water depth. The findings emphasise the extent of MP pollution and illustrate the value of Nile Red for large scale mapping at relatively low cost.


Assuntos
Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos , Plásticos , Reino Unido , Poluentes Químicos da Água/análise
2.
Mar Pollut Bull ; 171: 112708, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34273726

RESUMO

The South China Sea (SCS) is recognised as a global hotspot for plastic pollution. We review available field studies and identify a significant lack of data needed to construct a simple mass balance box model for plastic pollution in the SCS. Fundamental information on plastic mass input, transfer and sink terms are simply not available. Also unknown are the rates of accumulation in different environments, the dispersal pathways of plastic particles of different density, the residence times of plastic in the water column and the rate at which macroplastics are transformed into microplastics in different environments. Filling these information gaps is critical for states to determine adequate response measures, including developing and tracking impact of policies to deal with the problem of plastic pollution in the SCS.


Assuntos
Plásticos , Poluentes Químicos da Água , China , Monitoramento Ambiental , Microplásticos , Poluentes Químicos da Água/análise
3.
Mar Pollut Bull ; 168: 112462, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33993039

RESUMO

Microplastics (MPs) are ubiquitous in marine environment. The prevalence of MPs in coastal and lagoon sediments, and water were studied in two Marine Protected Areas (MPAs); Bundala National Park (BNP) and Hikkaduwa Marine National Park (HNP) in Sri Lanka. Both areas are important for turtles, birds and coral ecosystems, all of which are particularly threatened by MPs. Abundance of MPs was generally higher in both coastal sediments and waters in HNP (111±29 MPs/m2 for sediments and 0.515±0.054 MPs/m3 for water) than in the BNP (102±16 MPs/m2 for sediments and 0.276±0.077 MPs/m3 for water). The most common shape and polymer type of MPs were fragments and Polyethylene respectively. This research is the first to survey MPs in MPAs in Sri Lanka and provides a baseline of MPs pollution in these environments for future research and management.


Assuntos
Microplásticos , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos , Plásticos , Sri Lanka , Poluentes Químicos da Água/análise
4.
Sci Total Environ ; 769: 145222, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33736229

RESUMO

Marine litter is a global problem which poses an increasing threat to ecosystem services, human health, safety and sustainable livelihoods. In order to better plan plastic pollution monitoring and clean-up activities, and to develop policies and programmes to deter and mitigate plastic pollution, information is urgently needed on the different types of coastal ecosystem that are impacted by land-sourced plastic inputs, especially those located in proximity to river mouths where plastic waste is discharged into the ocean. We overlayed the most current existing information on the input of plastic to the sea from land-based sources with maps of coastal environments and ecosystems. We found an inverse relationship exists between coastal geomorphic type, plastic trapping efficiency and the mass of plastic received. River-dominated coasts comprise only 0.87% of the global coast and yet they receive 52% of plastic pollution delivered by fluvial systems. Tide-dominated coasts receive 29.9% of river-borne plastic pollution and this is also where mangrove and salt marsh habitats are most common. Wave-dominated coasts receive 11.6% of river-borne plastic pollution and this is where seagrass habitat is most common. Finally, rocky shores comprise 72.5% of the global coast, containing fjords and coral reefs, while only receiving 6.4% of river-borne plastic pollution. Mangroves are the most proximal to river-borne plastic pollution point sources of the four habitat types studied here; 54.0% of mangrove habitat is within 20 km of a river that discharges more than 1 t/yr of plastic pollution into the ocean. For seagrass, salt marsh and coral reefs the figures are 24.1%, 22.7% and 16.5%, respectively. The findings allow us to better understand the environmental fate of plastic pollution, to advance numerical models and to guide managers and decision-makers on the most appropriate responses and actions needed to monitor and reduce plastic pollution.

5.
Tijdschr Psychiatr ; 63(2): 133-137, 2021.
Artigo em Holandês | MEDLINE | ID: mdl-33620726

RESUMO

Background DESPITE VARIOUS NATIONAL INITIATIVES AND A STRONG MENTAL HEALTH CARE SYSTEM, THE NUMBER OF SUICIDES IN THE NETHERLANDS AND FLANDERS HAS NOT CHANGED AS HOPED. Aim TO PROVIDE INSIGHT INTO THE CURRENT SUICIDE PREVENTION POLICY IN THE NETHERLANDS AND FLANDERS, AND THE EVIDENCE ON THEIR EFFECTIVENESS. Method DISCUSSION OF UNIVERSAL, SELECTIVE AND INDICATED PREVENTION INITIATIVES, AND OF THE EVIDENCE FOR THE VARIOUS INITIATIVES, BASED ON THE USE OF REVIEWS AND META-ANALYSIS. Results THERE IS A NATIONAL SUICIDE PREVENTION AGENDA IN BOTH THE NETHERLANDS AND FLANDERS. IT IS DIFFICULT TO DEMONSTRATE THE DIRECT EFFECT OF THE VARIOUS INITIATIVES ON NATIONAL SUICIDE RATES, BECAUSE OF THE LOW BASE RATE, AND BECAUSE OF ITS MULTIPLE CAUSES. Conclusion THERE ARE LITTLE EVIDENCE FOR SUICIDE PREVENTION STRATEGIES. THIS DOES NOT MEAN SUICIDE PREVENTION HAS NO USE, BUT MODESTY SEEMS IN PLACE. Key words EVALUATION, POLICY, RCT, SUICIDE PREVENTION TIJDSCHRIFT VOOR PSYCHIATRIE 63(2021)2, 133-137.


Assuntos
Prevenção do Suicídio , Humanos , Países Baixos
6.
Mar Pollut Bull ; 161(Pt A): 111827, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33213857

RESUMO

The increasing abundance of marine litter is impacting the environment, human health and economies in the South Pacific. Small Islands Developing States are particularly affected by marine litter, primarily due to insufficient waste management systems. For the first time, marine litter was quantified and characterised on 13 beaches in Solomon Islands and Vanuatu in the South Pacific region using the OSPAR beach litter monitoring guidelines. A total of 1053 (±1017) and 974 (±745) items of litter per 100 m beach were recorded in Solomon Islands and Vanuatu respectively. Litter composition and distribution show that the majority of the litter comes from local land-based sources and large quantities of fragments and single use plastics were found by cities and river mouths. Actions to reduce single use plastic, improve collection, reuse and recycling, together with outreach campaigns would reduce marine litter significantly in these countries. Furthermore, there is great potential to develop a more circular economy to manage the substantial quantities of recyclable items that were found stranded on the beaches.


Assuntos
Praias , Resíduos , Monitoramento Ambiental , Humanos , Ilhas , Melanesia , Plásticos , Resíduos Sólidos , Inquéritos e Questionários , Vanuatu , Resíduos/análise
7.
Mucosal Immunol ; 13(3): 423-436, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31819170

RESUMO

Chronic obstructive pulmonary disease (COPD) is a highly prevalent respiratory disease characterized by airflow limitation and chronic inflammation. MiR-155 is described as an ancient regulator of the immune system. Our objective was to establish a role for miR-155 in cigarette smoke (CS)-induced inflammation and COPD. We demonstrate increased miR-155 expression by RT-qPCR in lung tissue of smokers without airflow limitation and patients with COPD compared to never smokers and in lung tissue and alveolar macrophages of CS-exposed mice compared to air-exposed mice. In addition, we exposed wild type and miR-155 deficient mice to CS and show an attenuated inflammatory profile in the latter. Alveolar macrophages were sorted by FACS from the different experimental groups and their gene expression profile was analyzed by RNA sequencing. This analysis revealed increased expression of miR-155 targets and an attenuation of the CS-induced increase in inflammation-related genes in miR-155 deficient mice. Moreover, intranasal instillation of a specific miR-155 inhibitor attenuated the CS-induced pulmonary inflammation in mice. Finally, elastase-induced emphysema and lung functional changes were significantly attenuated in miR-155 deficient mice. In conclusion, we highlight a role for miR-155 in CS-induced inflammation and the pathogenesis of COPD, implicating miR-155 as a new therapeutic target in COPD.


Assuntos
Fumar Cigarros/efeitos adversos , Suscetibilidade a Doenças , MicroRNAs/genética , Pneumonia/etiologia , Doença Pulmonar Obstrutiva Crônica/etiologia , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Mediadores da Inflamação/metabolismo , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/metabolismo , Masculino , Camundongos , Camundongos Knockout , Enfisema Pulmonar/etiologia , Enfisema Pulmonar/metabolismo , Enfisema Pulmonar/patologia , Interferência de RNA
8.
Ecotoxicol Environ Saf ; 187: 109839, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31670240

RESUMO

The impact of marine litter, particularly plastic waste, is widely acknowledged as a growing global concern. Marine litter is an understudied issue in the Regional Organisation for Protection of the Marine Environment (ROPME) Sea Area where rapid economic growth has already placed considerable stress on infrastructure and coastal ecosystems. This paper outlines some of the drivers for waste generation in region and reviews the available literature to summarise the current state of knowledge on the environmental fate, behaviour and impact of marine litter within the ROPME Sea Area. While data is limited, those studies conducted demonstrate marine litter is posing a clear and growing threat to the environmental and socioeconomic prosperity of the ROPME Sea Area. The development of regional and national marine litter reduction plans are clearly a priority to focus and coordinate activity across multiple stakeholders. Discussion of the potential environmental impacts arising as a result of marine litter are presented together with a roadmap for establishing and implementing a ROPME Sea Area Marine Litter and Single-Use Plastic Action Plan.


Assuntos
Conservação dos Recursos Hídricos/métodos , Monitoramento Ambiental/métodos , Plásticos/análise , Resíduos/análise , Conservação dos Recursos Hídricos/legislação & jurisprudência , Ecossistema , Meio Ambiente , Oceano Índico , Controle Social Formal
9.
Clin Exp Allergy ; 48(7): 773-786, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29772098

RESUMO

Outdoor air pollution is a major environmental health problem throughout the world. In particular, exposure to particulate matter (PM) has been associated with the development and exacerbation of several respiratory diseases, including asthma. Although the adverse health effects of PM have been demonstrated for many years, the underlying mechanisms have not been fully identified. In this review, we focus on the role of the lung epithelium and specifically highlight multiple cytokines in PM-induced respiratory responses. We describe the available literature on the topic including in vitro studies, findings in humans (ie observations in human cohorts, human controlled exposure and ex vivo studies) and in vivo animal studies. In brief, it has been shown that exposure to PM modulates the airway epithelium and promotes the production of several cytokines, including IL-1, IL-6, IL-8, IL-25, IL-33, TNF-α, TSLP and GM-CSF. Further, we propose that PM-induced type 2-promoting cytokines are important mediators in the acute and aggravating effects of PM on airway inflammation. Targeting these cytokines could therefore be a new approach in the treatment of asthma.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Poluição do Ar/efeitos adversos , Alérgenos/imunologia , Hiper-Reatividade Brônquica/imunologia , Hipersensibilidade/imunologia , Material Particulado/efeitos adversos , Animais , Asma/imunologia , Hiper-Reatividade Brônquica/genética , Hiper-Reatividade Brônquica/metabolismo , Hiper-Reatividade Brônquica/patologia , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Hipersensibilidade/genética , Hipersensibilidade/metabolismo , Hipersensibilidade/patologia , Mediadores da Inflamação/metabolismo , Mucosa Respiratória/imunologia , Mucosa Respiratória/metabolismo , Mucosa Respiratória/patologia
10.
Sci Total Environ ; 630: 790-798, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29494980

RESUMO

Marine litter presents a global problem, with increasing quantities documented in recent decades. The distribution and abundance of marine litter on the seafloor off the United Kingdom's (UK) coasts were quantified during 39 independent scientific surveys conducted between 1992 and 2017. Widespread distribution of litter items, especially plastics, were found on the seabed of the North Sea, English Channel, Celtic Sea and Irish Sea. High variation in abundance of litter items, ranging from 0 to 1835 pieces km-2 of seafloor, was observed. Plastic tems such as bags, bottles and fishing related debris were commonly observed across all areas. Over the entire 25-year period (1992-2017), 63% of the 2461 trawls contained at least one plastic litter item. There was no significant temporal trend in the percentage of trawls containing any or total plastic litter items across the long-term datasets. Statistically significant trends, however, were observed in specific plastic litter categories only. These trends were all positive except for a negative trend in plastic bags in the Greater North Sea - suggesting that behavioural and legislative changes could reduce the problem of marine litter within decades.

11.
Mar Environ Res ; 124: 118-129, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26733271

RESUMO

The European Union Marine Strategy Framework Directive (MSFD) requires individual member states to develop a robust set of tools for defining eleven qualitative descriptors of Good Environmental Status (GES), such as demonstrating that "Concentrations of contaminants are at levels not giving rise to pollution effects" (GES descriptor 8). Adopting the recommendations of the ICES/OSPAR Study Group for the Integrated Monitoring of Contaminants and Biological Effects (SGIMC), we present a case study demonstrating how the proposed approach, using chemical contaminant (metals and polycyclic aromatic hydrocarbons and polychlorinated biphenyls) and biological effects (EROD, bile metabolites and pathology) data in different matrices (sediment and biota), could be used to contribute to the determination of GES in a region of the North Sea region off the east coast of the UK.


Assuntos
Monitoramento Ambiental/métodos , Política Ambiental , Poluição da Água/prevenção & controle , Conservação dos Recursos Naturais/métodos , Ecossistema , União Europeia , Metais , Bifenilos Policlorados , Hidrocarbonetos Policíclicos Aromáticos , Água do Mar , Poluição da Água/legislação & jurisprudência , Poluição da Água/estatística & dados numéricos
12.
Thorax ; 70(4): 353-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25563773

RESUMO

The upper and lower airways are closely linked from an anatomical, histological and immunological point of view, with inflammation in one part of the airways influencing the other part. Despite the concept of global airway disease, the upper airways tend to be overlooked by respiratory physicians. We provide a clinical overview of the most important and recent insights in rhinitis and rhinosinusitis in relation to lower airway disease. We focus on the various exogenous and endogenous factors that play a role in the development and aggravation of chronic upper airway inflammation. In addition to the classical inhaled allergens or microorganisms with well-defined pathophysiological mechanisms in upper airway disease, environmental substances such as cigarette smoke, diesel exhaust particles and occupational agents affecting lower airway homeostasis have recently gained attention in upper airway research. We are only at the beginning of understanding the complex interplay between exogenous and endogenous factors like genetic, immunological and hormonal influences on chronic upper airway inflammation. From a clinical perspective, the involvement of upper and lower airway disease in one patient can only be fully appreciated by doctors capable of understanding the interplay between upper and lower airway inflammation.


Assuntos
Rinite/etiologia , Sinusite/etiologia , Poluição do Ar/efeitos adversos , Alérgenos/efeitos adversos , Infecções Bacterianas/complicações , Humanos , Depuração Mucociliar/fisiologia , Micoses/complicações , Exposição Ocupacional/efeitos adversos , Rinite/fisiopatologia , Sinusite/fisiopatologia , Viroses/complicações
13.
Allergy ; 68(4): 446-53, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23347053

RESUMO

BACKGROUND: Staphylococcal enterotoxin B (SEB) is a superantigen known to be a modulator of chronic airway inflammation in mice and humans, yet little is known about the mechanisms that regulate its interaction with the innate immune system. We investigated this mechanism in a murine model of allergic airway inflammation induced by OVA (ovalbumin) in the presence of SEB. METHODS: Superantigen-induced allergic inflammation was studied in IL-1R knockout (KO) mice exposed to OVA+SEB. Multicolor flow cytometry was used to analyze the inflammatory cell profile in airways and lymph nodes. Production of IL-4, IL-5, IL-10, and IL-13 in lymph nodes was assessed by Luminex technology. RESULTS: In wild-type mice, endonasal instillation of OVA+SEB induced a pulmonary inflammation, characterized by an increase in the number of eosinophils, T cells, and dendritic cells and in the production of Th2 cytokines and OVA-specific IgE. In IL-1R KO mice exposed to OVA+SEB, attraction of CD4+ cells and production of Th2 cytokines were reduced. However, knocking out IL-1R did not affect any of the features of allergic airway inflammation, such as bronchial eosinophilia, OVA-specific IgE production and goblet cell metaplasia. CONCLUSION: We provide new insights into the mechanisms of airways allergy development in the presence of bacterial superantigen. The asthma features induced by OVA+SEB, such as bronchial eosinophilia, goblet cell proliferation, production of OVA-specific IgE and increase in inflammatory dendritic cells, are IL-1R independent. Yet, IL-1R signaling is crucial for CD4 cell accumulation and Th2 cytokine production.


Assuntos
Adjuvantes Imunológicos , Asma/imunologia , Asma/metabolismo , Enterotoxinas/imunologia , Receptores de Interleucina-1/metabolismo , Transdução de Sinais , Animais , Asma/genética , Quimiotaxia/genética , Quimiotaxia/imunologia , Citocinas/biossíntese , Citocinas/imunologia , Células Dendríticas/imunologia , Modelos Animais de Doenças , Eosinófilos/imunologia , Células Caliciformes/patologia , Hiperplasia , Imunoglobulina E/biossíntese , Imunoglobulina E/imunologia , Inflamação/imunologia , Linfonodos/imunologia , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Linfócitos/imunologia , Camundongos , Camundongos Knockout , Receptores de Interleucina-1/genética , Células Th2/imunologia
14.
Phys Rev Lett ; 109(17): 171803, 2012 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-23215177

RESUMO

A search for physics beyond the standard model is performed in events with at least three jets and large missing transverse momentum produced in proton-proton collisions at a center-of-mass energy of √s=7 TeV. No significant excess of events above the expected backgrounds is observed in 4.98 fb(-1) of data collected with the CMS detector at the Large Hadron Collider. The results are presented in the context of the constrained minimal supersymmetric extension of the standard model and more generically for simplified models. For the simplified models of gluino-gluino and squark-squark production, gluino masses below 1.0 TeV and squark masses below 0.76 TeV are excluded in case the lightest supersymmetric particle mass is below 200 GeV. These results significantly extend previous searches.

15.
Phys Rev Lett ; 109(15): 152303, 2012 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-23102301

RESUMO

The transverse energy (E(T)) in Pb-Pb collisions at 2.76 TeV nucleon-nucleon center-of-mass energy (√(s(NN)) has been measured over a broad range of pseudorapidity (η) and collision centrality by using the CMS detector at the LHC. The transverse energy density per unit pseudorapidity (dE(T)/dη) increases faster with collision energy than the charged particle multiplicity. This implies that the mean energy per particle is increasing with collision energy. At all pseudorapidities, the transverse energy per participating nucleon increases with the centrality of the collision. The ratio of transverse energy per unit pseudorapidity in peripheral to central collisions varies significantly as the pseudorapidity increases from η=0 to |η|=5.0. For the 5% most central collisions, the energy density per unit volume is estimated to be about 14 GeV/fm(3) at a time of 1 fm/c after the collision. This is about 100 times larger than normal nuclear matter density and a factor of 2.6 times higher than the energy density reported at √(s(NN))=200 GeV at the Relativistic Heavy Ion Collider.

16.
Phys Rev Lett ; 109(2): 022301, 2012 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-23030154

RESUMO

The azimuthal anisotropy of charged particles in Pb-Pb collisions at sqrt[s(NN)]=2.76 TeV is measured with the CMS detector at the LHC over an extended transverse momentum (p(T)) range up to approximately 60 GeV/c. The data cover both the low-p(T) region associated with hydrodynamic flow phenomena and the high-p(T) region where the anisotropies may reflect the path-length dependence of parton energy loss in the created medium. The anisotropy parameter (v2) of the particles is extracted by correlating charged tracks with respect to the event-plane reconstructed by using the energy deposited in forward-angle calorimeters. For the six bins of collision centrality studied, spanning the range of 0-60% most-central events, the observed v2 values are found to first increase with p(T), reaching a maximum around p(T)=3 GeV/c, and then to gradually decrease to almost zero, with the decline persisting up to at least pp(T)=40 GeV/c over the full centrality range measured.

17.
Phys Rev Lett ; 108(25): 252002, 2012 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-23004588

RESUMO

The observation of a new b baryon via its strong decay into Ξ(b)(-) π(+) (plus charge conjugates) is reported. The measurement uses a data sample of pp collisions at sqrt[s] = 7 TeV collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 5.3 fb(-1). The known Ξ(b)(-) baryon is reconstructed via the decay chain Ξ(b)(-) → J/ψΞ(-) → µ(+) µ(-) Λ(0) π(-), with Λ(0) → pπ(-). A peak is observed in the distribution of the difference between the mass of the Ξ(b)(-) π(+) system and the sum of the masses of the Ξ(b)(-) and π(+), with a significance exceeding 5 standard deviations. The mass difference of the peak is 14.84 ± 0.74(stat) ± 0.28(syst) MeV. The new state most likely corresponds to the J(P) = 3/2(+) companion of the Ξ(b).

18.
Phys Rev Lett ; 109(11): 111806, 2012 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-23005617

RESUMO

A measurement of the electron charge asymmetry in inclusive pp→W+X→eν+X production at sqrt[s]=7 TeV is presented based on data recorded by the CMS detector at the LHC and corresponding to an integrated luminosity of 840 pb(-1). The electron charge asymmetry reflects the unequal production of W(+) and W(-) bosons in pp collisions. The electron charge asymmetry is measured in bins of the absolute value of electron pseudorapidity in the range of |η|<2.4. The asymmetry rises from about 0.1 to 0.2 as a function of the pseudorapidity and is measured with a relative precision better than 7%. This measurement provides new stringent constraints for parton distribution functions.

19.
Phys Rev Lett ; 109(12): 121801, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-23005937

RESUMO

The dimuon invariant mass spectrum is searched in the range between 5.5 and 14 GeV for a light pseudoscalar Higgs boson a, predicted in a number of new physics models, including the next-to-minimal supersymmetric standard model. The data sample used in the search corresponds to an integrated luminosity of 1.3 fb(-1) collected in pp collisions at √s = 7 TeV with the CMS detector at the LHC. No excess is observed above the background predictions and upper limits are set on the cross section times branching fraction σ × B(pp→a→µ(+)µ(-)) in the range of 1.5-7.5 pb. These results improve on existing bounds on the abb coupling for m(a) < m(Υ(1S)) and are the first significant limits for m(a) > m(Υ(3S)). Constraints on the supersymmetric parameter space are presented in the context of the next-to-minimal model.

20.
Phys Rev Lett ; 109(7): 071803, 2012 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-23006358

RESUMO

A search for new physics is performed in events with two same-sign isolated leptons, hadronic jets, and missing transverse energy in the final state. The analysis is based on a data sample corresponding to an integrated luminosity of 4.98 fb(-1) produced in pp collisions at a center-of-mass energy of 7 TeV collected by the CMS experiment at the LHC. This constitutes a factor of 140 increase in integrated luminosity over previously published results. The observed yields agree with the standard model predictions and thus no evidence for new physics is found. The observations are used to set upper limits on possible new physics contributions and to constrain supersymmetric models. To facilitate the interpretation of the data in a broader range of new physics scenarios, information on the event selection, detector response, and efficiencies is provided.

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