The architecture of amyloid-like peptide fibrils revealed by X-ray scattering, diffraction and electron microscopy

Structural analysis of protein fibrillation is inherently challenging. Given the crucial role of fibrils in amyloid diseases, method advancement is urgently needed. A hybrid modelling approach is presented enabling detailed analysis of a highly ordered and hierarchically organized fibril of the GNNQQNY peptide fragment of a yeast prion protein. Data from small-angle X-ray solution scattering, fibre diffraction and electron microscopy are combined with existing high-resolution X-ray crystallographic structures to investigate the fibrillation process and the hierarchical fibril structure of the peptide fragment. The elongation of these fibrils proceeds without the accumulation of any detectable amount of intermediate oligomeric species, as is otherwise reported for, for example, glucagon, insulin and [alpha]-synuclein. Ribbons constituted of linearly arranged protofilaments are formed. An additional hierarchical layer is generated via the pairing of ribbons during fibril maturation. Based on the complementary data, a quasi-atomic resolution model of the protofilament peptide arrangement is suggested. The peptide structure appears in a [beta]-sheet arrangement reminiscent of the [beta]-zipper structures evident from high-resolution crystal structures, with specific differences in the relative peptide orientation. The complexity of protein fibrillation and structure emphasizes the need to use multiple complementary methods

CARWASH WASTEWATERS: CHARACTERISTICS, VOLUMES, AND TREATABILITY BY GRAVITY OIL SEPARATION

The aim of this research was to determine the characteristics, volumes and treatability of Full-service carwash wastewaters in Toluca (Mexico State). The average water use for Exterior-only wash was 50 L per small-size car and 170 L per medium-size vehicle (pick up, van or light truck). The Full-service wash (exterior, engine and chassis) required 170 L per small-size car and 300 L per light truck. Wastewaters were generally emulsified and contained high contaminant loads (in average, 1100 mg/L oil and grease, 4500 mg/L COD and 3500 mg/L Total Suspended Solids). Gravity oil separators used in the car washing facilities were able to reduce the pollutant loads (showing a 80 % efficiency) but usually not enough to meet the sewer discharge standards or reuse requirements. The data provided by the study are useful for screening the applicable technologies and setting the design capacity of the reclaim systems that are needed in the Mexican car washing sector

SUSY-electroweak one-loop contributions to Flavour-Changing Higgs-Boson Decays

The SUSY-EW one-loop quantum contributions to flavour-changing MSSM Higgs-boson decays into $b \bar s$ and $s \bar b$ are computed and discussed. We use the full diagrammatic approach that is valid for all $\tan \beta$ values and do not rely on the mass-insertion approximation for the characteristic flavour-changing parameter. We analyze in full detail the dependence of these flavour-changing partial widths on all the relevant MSSM parameters and also study the non-decoupling behaviour of these widths with the SUSY mass parameters. We find that these contributions are sizable as compared to the SM ones, and together with the SUSY-QCD contributions they can be very efficient as an indirect method in the future search for Supersymmetry.Comment: LaTeX, 25 pages, 12 figures. Text improved and References added. Version to appear in Phys.Rev.

The CP-conserving two-Higgs-doublet model: the approach to the decoupling limit

A CP-even neutral Higgs boson with Standard-Model-like couplings may be the lightest scalar of a two-Higgs-doublet model. We study the decoupling limit of the most general CP-conserving two-Higgs-doublet model, where the mass of the lightest Higgs scalar is significantly smaller than the masses of the other Higgs bosons of the model. In this case, the properties of the lightest Higgs boson are nearly indistinguishable from those of the Standard Model Higgs boson. The first non-trivial corrections to Higgs couplings in the approach to the decoupling limit are also evaluated. The importance of detecting such deviations in precision Higgs measurements at future colliders is emphasized. We also clarify the case in which a neutral Higgs boson can possess Standard-Model-like couplings in a regime where the decoupling limit does not apply. The two-Higgs-doublet sector of the minimal supersymmetric model illustrates many of the above features.Comment: 54 pages, 2 tables, revtex4 format, some new material added (including elegant forms for the three-Higgs and four-Higgs couplings) and typographical errors fixe

Quantifying the years of life lost due to COVID-19 in Colombia: preliminary estimates

To estimate the years of life lost (YLLs) due to COVID-19 in Colombia and assess its economic impact by valuing the potential years of productive life lost (PYLLs). We conducted an ecological study to estimate the number of premature deaths associated with COVID-19 and calculate the present value of their expected future earnings using a discount rate of 3%. We considered deaths occurred from March to November 9, 2020. We used the modified criteria in the 2010 Global Burden of Disease (GBD) Study to estimate YLLs, adding the deaths for each age group and multiplied by the life expectancy of the respective age group up to the age limit considered. From the human capital approach, we estimated PYLLs to show the number of years of premature deaths caused by COVID-19, when fatalities occurred between 15-64 years old, the timeframe of economically active life for all estimates. We present results in 2020 U.S. dollars. The 32,974 deaths from COVID-19 have produced 697,512 YLLs, of which 66.0% are in men. Around 76.2% of these YLLs occur in people >50 years. On average, each death from COVID-19 contributed 21.2 YLL. The YLLs rate is 1,385 (women: 963; men: 1,787) per 100,000 inhabitants. The mean rate of YLLs in people aged ≥50 years is about ten times that of those <50 years (5,059 vs. 561 per 100,000). Premature deaths in the Colombian economically active population accounted for 89,667 PYLLs (74.6% in men). 58.8% of the PYLLs occurred in the population aged 40-64 years. The economic burden associated with this goes from US$168 to US$306 million (0.05-0.10% of the 2019 gross domestic product). At the end of 2020, COVID-19 would be the leading cause of death in Colombia and the most critical disease burden factor, above cardiovascular diseases, and neonatal disorders

Induction of engineered residual stresses fields and enhancement of fatigue life of high reliability metallic components by laser shock processing

Laser shock processing (LSP) is being increasingly applied as an effective technology for the improvement of metallic materials mechanical and surface properties in different types of components as a means of enhancement of their corrosion and fatigue life behavior. As reported in previous contributions by the authors, a main effect resulting from the application of the LSP technique consists on the generation of relatively deep compression residual stresses field into metallic alloy pieces allowing an improved mechanical behaviour, explicitly the life improvement of the treated specimens against wear, crack growth and stress corrosion cracking. Additional results accomplished by the authors in the line of practical development of the LSP technique at an experimental level (aiming its integral assessment from an interrelated theoretical and experimental point of view) are presented in this paper. Concretely, follow-on experimental results on the residual stress profiles and associated surface properties modification successfully reached in typical materials (especially Al and Ti alloys characteristic of high reliability components in the aerospace, nuclear and biomedical sectors) under different LSP irradiation conditions are presented along with a practical correlated analysis on the protective character of the residual stress profiles obtained under different irradiation strategies. Additional remarks on the improved character of the LSP technique over the traditional “shot peening” technique in what concerns depth of induced compressive residual stresses fields are also made through the pape

Long-Baseline Neutrino Facility (LBNF) and Deep Underground Neutrino Experiment (DUNE) Conceptual Design Report Volume 2: The Physics Program for DUNE at LBNF

The Physics Program for the Deep Underground Neutrino Experiment (DUNE) at the Fermilab Long-Baseline Neutrino Facility (LBNF) is described

Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

This paper presents measurements of the $W^+ \rightarrow \mu^+\nu$ and $W^- \rightarrow \mu^-\nu$ cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13

Measurements of fiducial and differential cross sections for Higgs boson production in the diphoton decay channel at s√=8 TeV with ATLAS

Measurements of fiducial and differential cross sections are presented for Higgs boson production in proton-proton collisions at a centre-of-mass energy of s√=8 TeV. The analysis is performed in the H → γγ decay channel using 20.3 fb−1 of data recorded by the ATLAS experiment at the CERN Large Hadron Collider. The signal is extracted using a fit to the diphoton invariant mass spectrum assuming that the width of the resonance is much smaller than the experimental resolution. The signal yields are corrected for the effects of detector inefficiency and resolution. The pp → H → γγ fiducial cross section is measured to be 43.2 ±9.4(stat.) − 2.9 + 3.2 (syst.) ±1.2(lumi)fb for a Higgs boson of mass 125.4GeV decaying to two isolated photons that have transverse momentum greater than 35% and 25% of the diphoton invariant mass and each with absolute pseudorapidity less than 2.37. Four additional fiducial cross sections and two cross-section limits are presented in phase space regions that test the theoretical modelling of different Higgs boson production mechanisms, or are sensitive to physics beyond the Standard Model. Differential cross sections are also presented, as a function of variables related to the diphoton kinematics and the jet activity produced in the Higgs boson events. The observed spectra are statistically limited but broadly in line with the theoretical expectations

Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC

The uncertainty on the calorimeter energy response to jets of particles is derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the calorimeter response to single isolated charged hadrons is measured and compared to the Monte Carlo simulation using proton-proton collisions at centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009 and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter response to specific types of particles (positively and negatively charged pions, protons, and anti-protons) is measured and compared to the Monte Carlo predictions. Finally, the jet energy scale uncertainty is determined by propagating the response uncertainty for single charged and neutral particles to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3% for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table, submitted to European Physical Journal