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Storm runoff quality and pollutant loading from commercial, residential, and industrial catchments in the tropic

Chow MF, Yusop Z, Shirazi SM

Environ Monit Assess, 2013 Oct;185(10):8321-31.
PMID: 23591675 DOI: 10.1007/s10661-013-3175-6

Information on the pollution level and the influence of hydrologic regime on the stormwater pollutant loading in tropical urban areas are still scarce. More local data are still required because rainfall and runoff generation processes in tropical environment are very different from the temperate regions. This study investigated the extent of urban runoff pollution in residential, commercial, and industrial catchments in the south of Peninsular Malaysia. Stormwater samples and flow rate data were collected from 51 storm events. Samples were analyzed for total suspended solids, 5-day biochemical oxygen demand, chemical oxygen demand, oil and grease (O&G), nitrate nitrogen (NO3-N), nitrite nitrogen, ammonia nitrogen, soluble reactive phosphorus, total phosphorus (TP), and zinc (Zn). It was found that the event mean concentrations (EMCs) of pollutants varied greatly between storm characteristics and land uses. The results revealed that site EMCs for residential catchment were lower than the published data but higher for the commercial and industrial catchments. All rainfall variables were negatively correlated with EMCs of most pollutants except for antecedent dry days (ADD). This study reinforced the earlier findings on the importance of ADD for causing greater EMC values with exceptions for O&G, NO3-N, TP, and Zn. In contrast, the pollutant loadings are influenced primarily by rainfall depth, mean intensity, and max 5-min intensity in all the three catchments. Overall, ADD is an important variable in multiple linear regression models for predicting the EMC values in the tropical urban catchments.
Fulltext Experimental study on tsunami risk reduction on coastal building fronted by sea wall

Rahman S, Akib S, Khan MT, Shirazi SM

ScientificWorldJournal, 2014;2014:729357.
PMID: 24790578 DOI: 10.1155/2014/729357

This experimental study was conducted to idealize the efficacy of sea wall in controlling the tsunami forces on onshore structures. Different types of sea walls were placed in front of the building model. The tsunami forces and the wave heights were measured with and without the sea wall conditions. Types of sea wall, wall height, and wall positions were varied simultaneously to quantify the force reductions. Maximum of 41% forces was reduced by higher sea wall, positioned closer proximity to the model whereas this reduction was about 27% when the wall height was half of the high wall. Experimental investigations revealed that wall with adequate height and placed closer to the structures enables a satisfactory predictor of the force reduction on onshore structures. Another set of tests were performed with perforated wall placing near the building model. Less construction cost makes the provision of perforated sea wall interesting. The overall results showed that the efficacy of perforated wall is almost similar to solid wall. Hence, it can be efficiently used instead of solid wall. Moreover, overtopped water that is stuck behind the wall is readily gone back to the sea through perforations releasing additional forces on the nearby structures.
Fulltext Runoff potentiality of a watershed through SCS and functional data analysis technique

Adham MI, Shirazi SM, Othman F, Rahman S, Yusop Z, Ismail Z

ScientificWorldJournal, 2014;2014:379763.
PMID: 25152911 DOI: 10.1155/2014/379763

Runoff potentiality of a watershed was assessed based on identifying curve number (CN), soil conservation service (SCS), and functional data analysis (FDA) techniques. Daily discrete rainfall data were collected from weather stations in the study area and analyzed through lowess method for smoothing curve. As runoff data represents a periodic pattern in each watershed, Fourier series was introduced to fit the smooth curve of eight watersheds. Seven terms of Fourier series were introduced for the watersheds 5 and 8, while 8 terms of Fourier series were used for the rest of the watersheds for the best fit of data. Bootstrapping smooth curve analysis reveals that watersheds 1, 2, 3, 6, 7, and 8 are with monthly mean runoffs of 29, 24, 22, 23, 26, and 27 mm, respectively, and these watersheds would likely contribute to surface runoff in the study area. The purpose of this study was to transform runoff data into a smooth curve for representing the surface runoff pattern and mean runoff of each watershed through statistical method. This study provides information of runoff potentiality of each watershed and also provides input data for hydrological modeling.
Fulltext Sustainability of rainwater harvesting system in terms of water quality

Rahman S, Khan MT, Akib S, Din NB, Biswas SK, Shirazi SM

ScientificWorldJournal, 2014;2014:721357.
PMID: 24701186 DOI: 10.1155/2014/721357

Water is considered an everlasting free source that can be acquired naturally. Demand for processed supply water is growing higher due to an increasing population. Sustainable use of water could maintain a balance between its demand and supply. Rainwater harvesting (RWH) is the most traditional and sustainable method, which could be easily used for potable and nonpotable purposes both in residential and commercial buildings. This could reduce the pressure on processed supply water which enhances the green living. This paper ensures the sustainability of this system through assessing several water-quality parameters of collected rainwater with respect to allowable limits. A number of parameters were included in the analysis: pH, fecal coliform, total coliform, total dissolved solids, turbidity, NH3-N, lead, BOD5, and so forth. The study reveals that the overall quality of water is quite satisfactory as per Bangladesh standards. RWH system offers sufficient amount of water and energy savings through lower consumption. Moreover, considering the cost for installation and maintenance expenses, the system is effective and economical.
Fulltext Antifungal activity of Fe3O4@SiO2/Schiff-base/Cu(II) magnetic nanoparticles against pathogenic Candida species

Azadi S, Azizipour E, Amani AM, Vaez A, Zareshahrabadi Z, Abbaspour A, et al.

Sci Rep, 2024 Mar 11;14(1):5855.
PMID: 38467729 DOI: 10.1038/s41598-024-56512-5

The antifungal efficacy and cytotoxicity of a novel nano-antifungal agent, the Fe3O4@SiO2/Schiff-base complex of Cu(II) magnetic nanoparticles (MNPs), have been assessed for targeting drug-resistant Candida species. Due to the rising issue of fungal infections, especially candidiasis, and resistance to traditional antifungals, there is an urgent need for new therapeutic strategies. Utilizing Schiff-base ligands known for their broad-spectrum antimicrobial activity, the Fe3O4@SiO2/Schiff-base/Cu(II) MNPs have been synthesized. The Fe3O4@SiO2/Schiff-base/Cu(II) MNPs was characterized by Fourier Transform-Infrared Spectroscopy (FT-IR), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Dynamic Light Scattering (DLS), Energy-dispersive X-ray (EDX), Vibrating Sample Magnetometer (VSM), and Thermogravimetric analysis (TGA), demonstrating successful synthesis. The antifungal potential was evaluated against six Candida species (C. dubliniensis, C. krusei, C. tropicalis, C. parapsilosis, C. glabrata, and C. albicans) using the broth microdilution method. The results indicated strong antifungal activity in the range of 8-64 μg/mL with the lowest MIC (8 μg/mL) observed against C. parapsilosis. The result showed the MIC of 32 μg/mL against C. albicans as the most common infection source. The antifungal mechanism is likely due to the disruption of the fungal cell wall and membrane, along with increased reactive oxygen species (ROS) generation leading to cell death. The MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay for cytotoxicity on mouse L929 fibroblastic cells suggested low toxicity and even enhanced cell proliferation at certain concentrations. This study demonstrates the promise of Fe3O4@SiO2/Schiff-base/Cu(II) MNPs as a potent antifungal agent with potential applications in the treatment of life-threatening fungal infections, healthcare-associated infections, and beyond.
Fulltext Fe3O4@SiO2/Schiff-base/Zn (II) nanocomposite functioning as a versatile antimicrobial agent against bacterial and fungal pathogens

Azadi S, Amani AM, Jangjou A, Vaez A, Zareshahrabadi Z, Zare A, et al.

Sci Rep, 2025 Feb 17;15(1):5694.
PMID: 39962153 DOI: 10.1038/s41598-025-86518-6

Antimicrobial resistance (AMR) presents a critical global health issue, necessitating novel therapeutic strategies to manage bacterial and fungal infections. This study explores the development and evaluation of multifunctional Fe3O₄@SiO₂/Schiff-base/Zn (II) magnetic nanocomposite (MNC) with enhanced antimicrobial properties. The synthesized MNC combines the magnetic characteristics of Fe₃O₄ magnetic nanoparticles (MNPs) with the antimicrobial properties of Schiff-base ligand functionalized with Zn (II) ions. The preparation involved the coprecipitation of Fe₃O₄, coating with SiO₂ via a modified Stöber method, and subsequent functionalization with Schiff-base/Zn (II) complex. Comprehensive characterization using FT-IR, XRD, SEM, TEM, DLS, EDX, VSM, and TGA confirmed successful synthesis, structural integrity, and superparamagnetic behavior of the MNPs and MNC. The antifungal and antibacterial activities were assessed against six Candida species and four bacterial strains using broth microdilution methods. The Fe₃O₄@SiO₂/Schiff-base/Zn (II) MNC exhibited significant inhibitory effects, with MIC values of 8-64 µg/mL for Candida species and 64-512 µg/mL for bacteria, demonstrating potent antimicrobial efficacy. The MTT assay indicated biocompatibility across various concentrations, except for slight cytotoxicity at 256 µg/mL after five days. To our knowledge, this is the first report integrating Zn (II) Schiff-base ligands into magnetic nanoparticles to achieve a versatile platform for both antimicrobial and biofilm inhibition applications.
Fulltext An intriguing approach toward antibacterial activity of green synthesized Rutin-templated mesoporous silica nanoparticles decorated with nanosilver

Abbasi M, Gholizadeh R, Kasaee SR, Vaez A, Chelliapan S, Fadhil Al-Qaim F, et al.

Sci Rep, 2023 Apr 12;13(1):5987.
PMID: 37046068 DOI: 10.1038/s41598-023-33095-1

In recent years, mesoporous silica nanoparticles (MSNs) have been applied in various biomedicine fields like bioimaging, drug delivery, and antibacterial alternatives. MSNs could be manufactured through green synthetic methods as environmentally friendly and sustainable synthesis approaches, to improve physiochemical characteristics for biomedical applications. In the present research, we used Rutin (Ru) extract, a biocompatible flavonoid, as the reducing agent and nonsurfactant template for the green synthesis of Ag-decorated MSNs. Transmission electron microscopy (TEM), zeta-potential, x-ray powder diffraction (XRD), fourier transform infrared (FTIR) spectroscopy analysis, scanning electron microscopy (SEM), brunauer-emmett-teller (BET) analysis, and energy-dispersive system (EDS) spectroscopy were used to evaluate the Ag-decorated MSNs physical characteristics. The antimicrobial properties were evaluated against Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and also different types of candida. The cytotoxicity test was performed by using the MTT assay. Based on the findings, the significant antimicrobial efficacy of Ru-Ag-decorated MSNs against both gram positive and gram negative bacteria and different types of fungi was detected as well as acceptable safety and low cytotoxicity even at lower concentrations. Our results have given a straightforward and cost-effective method for fabricating biodegradable Ag-decorated MSNs. The applications of these MSNs in the domains of biomedicine appear to be promising.
Fulltext MXene-based materials for enhanced water quality: Advances in remediation strategies

Amani AM, Abbasi M, Najdian A, Mohamadpour F, Kasaee SR, Kamyab H, et al.

Ecotoxicol Environ Saf, 2025 Feb;291:117817.
PMID: 39908870 DOI: 10.1016/j.ecoenv.2025.117817

Two-dimensional MXenes are promising candidates for water treatment because of their large surface area (e.g., exceeding 1000 m²/g for certain structures), high electrical conductivity (e.g., >1000 S/m), hydrophilicity, and chemical stability. Their strong sorption selectivity and effective reduction capacity, exemplified by heavy metal adsorption efficiencies exceeding 95 % in several studies, coupled with facile surface modification, make them suitable for removing diverse contaminants. Applications include the removal of heavy metals (e.g., achieving >90 % removal of Pb(II)), dye removal (e.g., demonstrating >80 % removal of methylene blue), and radioactive waste elimination. Furthermore, 3D MXene architecture exhibit enhanced performance in antibacterial activities (e.g., against bacteria), desalination rejection percentage, and photocatalytic degradation of organic contaminants. However, several challenges have remained, which necessitate further investigation into toxicity (e.g., assessing effects on aquatic organisms), scalability, and cost-effectiveness of large-scale production. This review summarizes recent advancements in 3D MXene-based functional materials for wastewater treatment and water remediation, critically analyzing their both potential and limitations.
Global, Regional, and National Burden of Bone Cancers, 1990 to 2023, With Forecasts to 2050: A Systematic Analysis for the Global Burden of Disease Study 2023

GBD 2023 Bone Cancer Collaborators, Monsereenusorn C, Bisignano C, May ML, Pritchett N, Kocarnik JM, et al.

JAMA Oncol, 2026 Oct 29.
PMID: 42955027 DOI: 10.1001/jamaoncol.2026.4274

IMPORTANCE: Primary bone cancers include multiple histologic types, with survival differing by age and location. Results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2023 were analyzed to support policies and initiatives worldwide.
OBJECTIVE: To estimate the global burden of bone cancer from 1990 to 2023 and forecast future trends to 2050.
DESIGN, SETTING, AND PARTICIPANTS: This systematic analysis estimated bone cancer incidence, mortality, and disability-adjusted life-years (DALYs) in 204 countries and territories grouped by GBD super-regions and World Bank income groups from 1990 to 2023, with forecasts through 2050. Individuals of all ages with bone cancers included in the GBD 2023 study were included in analyses. Data were analyzed from June 2023 to July 2025.
MAIN OUTCOMES AND MEASURES: The GBD 2023 study used standardized estimation methods to describe bone cancer incidence, mortality, and DALYs in 2023, as well as trends over the past 3 decades and forecasts through 2050. All estimates are presented with 95% uncertainty intervals (UIs), and age-standardized rates (ASRs) were calculated using GBD-specific age weights.
RESULTS: In 2023, there were 111 000 (95% UI, 81 300-164 000) malignant bone cancer cases, 76 600 (95% UI, 60 700-96 300) deaths, and 3.02 million (95% UI, 2.29 million-3.96 million) DALYs globally. A bimodal age distribution was noted in both incidence (peaking at ages 10 to 14 years and 65 to 69 years) and mortality (peaking at ages 15 to 19 years and 65 to 69 years). The highest ASRs for incidence were in Southeast Asia, East Asia, and Oceania (1.6 per 100 000; 95% UI, 1.1-2.4), while Sub-Saharan Africa had the highest ASRs for DALYs (51.0 per 100 000; 95% UI, 27.7-79.7). By World Bank income group, upper-middle-income countries had the highest ASRs for incidence, whereas low-income countries exhibited the highest ASRs for both mortality and DALYs. Globally, incident cases, deaths, and DALYs increased from 1990 to 2023, while global mortality and DALY ASRs were relatively stable; high-income countries experienced a decline in mortality and DALY ASRs. Forecasts suggest a potential increase in global cases and deaths by 2050.
CONCLUSIONS AND RELEVANCE: In this systematic analysis, the burden of bone cancer varied by age, geography, and time, underscoring global disparities. These findings provide valuable insights to inform health system planning and resource allocation tailored to different settings.
Fulltext Global Burden of Anorexia Nervosa and Bulimia Nervosa, 1990 to 2023, With Forecasts to 2050: A Global Burden of Disease Study 2023 Analysis

Bai R, Dong W, Wang X, Zhang A, Santomauro DF, GBD Eating Disorders Collaborators, et al.

JAMA Psychiatry, 2026 Oct 28.
PMID: 42949727 DOI: 10.1001/jamapsychiatry.2026.3457

IMPORTANCE: Eating disorders are a major cause of nonfatal mental health burden, yet global evidence on their long-term trends, geographic distribution, and future trajectories remains limited.
OBJECTIVE: To estimate the global, regional, and national prevalence and disability burden of anorexia nervosa and bulimia nervosa-and mortality attributable to anorexia nervosa-from 1990 to 2023, and to forecast prevalence to 2050.
DESIGN, SETTING, AND PARTICIPANTS: Using Global Burden of Disease (GBD) 2023 methods, data were synthesized from systematic literature reviews, population surveys, and vital registration systems. Estimates were produced for 204 countries and territories from 1990 to 2023, with forecasts through 2050. These data were analyzed from October 2025 to August 2026.
EXPOSURE: Anorexia nervosa or bulimia nervosa diagnosis.
MAIN OUTCOMES AND MEASURES: Counts and age-standardized rates with 95% uncertainty intervals (UIs) for anorexia nervosa and bulimia nervosa prevalence, years lived with disability (YLDs), and disability-adjusted life-years (DALYs), and anorexia nervosa mortality, reported by age, sex, and location.
RESULTS: In 2023, an estimated 18.1 million people (95% UI, 13.9-24.0) globally were living with anorexia nervosa or bulimia nervosa, of whom 12.6 million (69.4%) were female, 5.5 million were male (30.6%), and 41.2% were aged 10 to 24 years. These cases accounted for 3.83 million DALYs (95% UI, 2.23-5.69). Since 1990, the global number of prevalent cases increased by 71.0%, while age-standardized prevalence and DALY rates rose by about 21%. Females experienced substantially higher prevalence and DALY rates than males. The highest age-standardized prevalence rates were observed in high-income regions, particularly Australasia and Western Europe, whereas the largest relative increases in age-standardized prevalence occurred in East Asia, South Asia, and Southeast Asia. Forecasts indicate continued increases in prevalent cases through 2050.
CONCLUSIONS AND RELEVANCE: This GBD 2023 analysis found that anorexia nervosa and bulimia nervosa contribute substantially to global nonfatal health loss. These findings support the integration of eating disorders into mental health surveillance, prevention, and service planning worldwide.
Fulltext Searches for pair production of third-generation squarks in [Formula: see text][Formula: see text] pp collisions

Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, Brandstetter J, et al.

Eur Phys J C Part Fields, 2017;77(5):327.
PMID: 28943785 DOI: 10.1140/epjc/s10052-017-4853-2

Searches are presented for direct production of top or bottom squark pairs in proton-proton collisions at the CERN LHC. Two searches, based on complementary techniques, are performed in all-jet final states that are characterized by a significant imbalance in transverse momentum. An additional search requires the presence of a charged lepton isolated from other activity in the event. The data were collected in 2015 at a centre-of-mass energy of 13[Formula: see text] with the CMS detector and correspond to an integrated luminosity of 2.3[Formula: see text]. No statistically significant excess of events is found beyond the expected contribution from standard model processes. Exclusion limits are set in the context of simplified models of top or bottom squark pair production. Models with top and bottom squark masses up to 830 and 890[Formula: see text], respectively, are probed for light neutralinos. For models with top squark masses of 675[Formula: see text], neutralino masses up to 260[Formula: see text] are excluded at 95% confidence level.
Study of Jet Quenching with Z+jet Correlations in Pb-Pb and pp Collisions at sqrt[s]_{NN}=5.02 TeV

Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, Brandstetter J, et al.

Phys Rev Lett, 2017 Aug 25;119(8):082301.
PMID: 28952777 DOI: 10.1103/PhysRevLett.119.082301

The production of jets in association with Z bosons, reconstructed via the μ^{+}μ^{-} and e^{+}e^{-} decay channels, is studied in pp and, for the first time, in Pb-Pb collisions. Both data samples were collected by the CMS experiment at the LHC, at a nucleon-nucleon center-of-mass energy of 5.02 TeV. The Pb-Pb collisions were analyzed in the 0%-30% centrality range. The back-to-back azimuthal alignment was studied in both pp and Pb-Pb collisions for Z bosons with transverse momentum p_{T}^{Z}>60 GeV/c and a recoiling jet with p_{T}^{jet}>30 GeV/c. The p_{T} imbalance x_{jZ}=p_{T}^{jet}/p_{T}^{Z}, as well as the average number of jet partners per Z, R_{jZ}, was studied in intervals of p_{T}^{Z}. The R_{jZ} is found to be smaller in Pb-Pb than in pp collisions, which suggests that in Pb-Pb collisions a larger fraction of partons associated with the Z bosons fall below the 30 GeV/c p_{T}^{jet} threshold because they lose energy.
Fulltext Measurement of double-differential cross sections for top quark pair production in pp collisions at [Formula: see text][Formula: see text] and impact on parton distribution functions

Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, Brandstetter J, et al.

Eur Phys J C Part Fields, 2017;77(7):459.
PMID: 28943791 DOI: 10.1140/epjc/s10052-017-4984-5

Normalized double-differential cross sections for top quark pair ([Formula: see text]) production are measured in pp collisions at a centre-of-mass energy of 8[Formula: see text] with the CMS experiment at the LHC. The analyzed data correspond to an integrated luminosity of 19.7[Formula: see text]. The measurement is performed in the dilepton [Formula: see text] final state. The [Formula: see text] cross section is determined as a function of various pairs of observables characterizing the kinematics of the top quark and [Formula: see text] system. The data are compared to calculations using perturbative quantum chromodynamics at next-to-leading and approximate next-to-next-to-leading orders. They are also compared to predictions of Monte Carlo event generators that complement fixed-order computations with parton showers, hadronization, and multiple-parton interactions. Overall agreement is observed with the predictions, which is improved when the latest global sets of proton parton distribution functions are used. The inclusion of the measured [Formula: see text] cross sections in a fit of parametrized parton distribution functions is shown to have significant impact on the gluon distribution.
Fulltext Measurement of the jet mass in highly boosted [Formula: see text] events from pp collisions at [Formula: see text][Formula: see text]

Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, Brandstetter J, et al.

Eur Phys J C Part Fields, 2017;77(7):467.
PMID: 28943793 DOI: 10.1140/epjc/s10052-017-5030-3

The first measurement of the jet mass [Formula: see text] of top quark jets produced in [Formula: see text] events from pp collisions at [Formula: see text] [Formula: see text] is reported for the jet with the largest transverse momentum [Formula: see text] in highly boosted hadronic top quark decays. The data sample, collected with the CMS detector, corresponds to an integrated luminosity of 19.7[Formula: see text]. The measurement is performed in the lepton+jets channel in which the products of the semileptonic decay [Formula: see text] with [Formula: see text] where [Formula: see text] is an electron or muon, are used to select [Formula: see text] events with large Lorentz boosts. The products of the fully hadronic decay [Formula: see text] with [Formula: see text] are reconstructed using a single Cambridge-Aachen jet with distance parameter [Formula: see text], and [Formula: see text] [Formula: see text]. The [Formula: see text] cross section as a function of [Formula: see text] is unfolded at the particle level and is used to test the modelling of highly boosted top quark production. The peak position of the [Formula: see text] distribution is sensitive to the top quark mass [Formula: see text], and the data are used to extract a value of [Formula: see text] to assess this sensitivity.
Fulltext Measurement of the top quark mass using single top quark events in proton-proton collisions at [Formula: see text] TeV

Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, Brandstetter J, et al.

Eur Phys J C Part Fields, 2017;77(5):354.
PMID: 28943789 DOI: 10.1140/epjc/s10052-017-4912-8

A measurement of the top quark mass is reported in events containing a single top quark produced via the electroweak t channel. The analysis is performed using data from proton-proton collisions collected with the CMS detector at the LHC at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 19.7 fb[Formula: see text]. Top quark candidates are reconstructed from their decay to a [Formula: see text] boson and a b quark, with the [Formula: see text] boson decaying leptonically to a muon and a neutrino. The final state signature and kinematic properties of single top quark events in the t channel are used to enhance the purity of the sample, suppressing the contribution from top quark pair production. A fit to the invariant mass distribution of reconstructed top quark candidates yields a value of the top quark mass of [Formula: see text]. This result is in agreement with the current world average, and represents the first measurement of the top quark mass in event topologies not dominated by top quark pair production, therefore contributing to future averages with partially uncorrelated systematic uncertainties and a largely uncorrelated statistical uncertainty.
Search for Low Mass Vector Resonances Decaying to Quark-Antiquark Pairs in Proton-Proton Collisions at sqrt[s]=13 TeV

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.

Phys Rev Lett, 2017 Sep 15;119(11):111802.
PMID: 28949210 DOI: 10.1103/PhysRevLett.119.111802

A search is reported for a narrow vector resonance decaying to quark-antiquark pairs in proton-proton collisions at sqrt[s]=13 TeV, collected with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 2.7 fb^{-1}. The vector resonance is produced at large transverse momenta, with its decay products merged into a single jet. The resulting signature is a peak over background in the distribution of the invariant mass of the jet. The results are interpreted in the framework of a leptophobic vector resonance and no evidence is found for such particles in the mass range of 100-300 GeV. Upper limits at 95% confidence level on the production cross section are presented in a region of mass-coupling phase space previously unexplored at the LHC. The region below 140 GeV has not been explored by any previous experiments.
Search for Supersymmetry in pp Collisions at sqrt[s]=13 TeV in the Single-Lepton Final State Using the Sum of Masses of Large-Radius Jets

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.

Phys Rev Lett, 2017 Oct 13;119(15):151802.
PMID: 29077436 DOI: 10.1103/PhysRevLett.119.151802

Results are reported from a search for supersymmetric particles in proton-proton collisions in the final state with a single lepton, multiple jets, including at least one b-tagged jet, and large missing transverse momentum. The search uses a sample of proton-proton collision data at sqrt[s]=13 TeV recorded by the CMS experiment at the LHC, corresponding to an integrated luminosity of 35.9 fb^{-1}. The observed event yields in the signal regions are consistent with those expected from standard model backgrounds. The results are interpreted in the context of simplified models of supersymmetry involving gluino pair production, with gluino decay into either on- or off-mass-shell top squarks. Assuming that the top squarks decay into a top quark plus a stable, weakly interacting neutralino, scenarios with gluino masses up to about 1.9 TeV are excluded at 95% confidence level for neutralino masses up to about 1 TeV.
Measurement of the B^{±} Meson Nuclear Modification Factor in Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, Brandstetter J, et al.

Phys Rev Lett, 2017 Oct 13;119(15):152301.
PMID: 29077459 DOI: 10.1103/PhysRevLett.119.152301

The differential production cross sections of B^{±} mesons are measured via the exclusive decay channels B^{±}→J/ψK^{±}→μ^{+}μ^{-}K^{±} as a function of transverse momentum in pp and Pb-Pb collisions at a center-of-mass energy sqrt[s_{NN}]=5.02 TeV per nucleon pair with the CMS detector at the LHC. The pp(Pb-Pb) data set used for this analysis corresponds to an integrated luminosity of 28.0 pb^{-1} (351 μb^{-1}). The measurement is performed in the B^{±} meson transverse momentum range of 7 to 50 GeV/c, in the rapidity interval |y|<2.4. In this kinematic range, a strong suppression of the production cross section by about a factor of 2 is observed in the Pb-Pb system in comparison to the expectation from pp reference data. These results are found to be roughly compatible with theoretical calculations incorporating beauty quark diffusion and energy loss in a quark-gluon plasma.
Fulltext A search for new phenomena in pp collisions at [Formula: see text] in final states with missing transverse momentum and at least one jet using the [Formula: see text] variable

Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.

Eur Phys J C Part Fields, 2017;77(5):294.
PMID: 28579921 DOI: 10.1140/epjc/s10052-017-4787-8

A search for new phenomena is performed in final states containing one or more jets and an imbalance in transverse momentum in pp collisions at a centre-of-mass energy of 13[Formula: see text]. The analysed data sample, recorded with the CMS detector at the CERN LHC, corresponds to an integrated luminosity of 2.3[Formula: see text]. Several kinematic variables are employed to suppress the dominant background, multijet production, as well as to discriminate between other standard model and new physics processes. The search provides sensitivity to a broad range of new-physics models that yield a stable weakly interacting massive particle. The number of observed candidate events is found to agree with the expected contributions from standard model processes, and the result is interpreted in the mass parameter space of fourteen simplified supersymmetric models that assume the pair production of gluinos or squarks and a range of decay modes. For models that assume gluino pair production, masses up to 1575 and 975[Formula: see text] are excluded for gluinos and neutralinos, respectively. For models involving the pair production of top squarks and compressed mass spectra, top squark masses up to 400[Formula: see text] are excluded.
Search for Charged Higgs Bosons Produced via Vector Boson Fusion and Decaying into a Pair of W and Z Bosons Using pp Collisions at sqrt[s]=13 TeV

Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, Brandstetter J, et al.

Phys Rev Lett, 2017 Oct 06;119(14):141802.
PMID: 29053305 DOI: 10.1103/PhysRevLett.119.141802

A search for charged Higgs bosons produced via vector boson fusion and decaying into W and Z bosons using proton-proton collisions at sqrt[s]=13 TeV is presented. The data sample corresponds to an integrated luminosity of 15.2 fb^{-1} collected with the CMS detector in 2015 and 2016. The event selection requires three leptons (electrons or muons), two jets with large pseudorapidity separation and high dijet mass, and missing transverse momentum. The observation agrees with the standard model prediction. Limits on the vector boson fusion production cross section times branching fraction for new charged physical states are reported as a function of mass from 200 to 2000 GeV and interpreted in the context of Higgs triplet models.

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