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Is the Archimedes principle a law of nature? Discussions in an 'extended teacher room'

Is a suction cup at the bottom of a bathtub subject to an upward force from the surrounding water, even if there is no water under it? A student question, posted in a teacher facebook group on a Monday morning, led to a discussion involving 21 comments with 225 replies offered by 16 teachers during the next few days, including several simple experiments, as well as modeling, to evaluate different

Role of Neutrophil Extracellular Traps Regarding Patients at Risk of Increased Disease Activity and Cardiovascular Comorbidity in Systemic Lupus Erythematosus

OBJECTIVE: Neutrophil extracellular traps (NET) are essential in host defense, but are also linked to inflammation and autoimmunity, including in systemic lupus erythematosus (SLE). We recently described that immune complexes (IC) induce NET formation, promoting SLE-like disease in mice. In the current study, we investigated, for the first time to our knowledge, the role of NET in human SLE and th

Heme-induced oxidation of cysteine groups of myofilament proteins leads to contractile dysfunction of permeabilized human skeletal muscle fibres

Background: Heme released from red blood cells targets a number of cell components including the cytoskeleton. The purpose of the present study was to determine the impact of free heme (20–300 µM) on human skeletal muscle fibres made available during orthopedic surgery. Methods: Isometric force production and oxidative protein modifications were monitored in permeabilized skeletal muscle fibre seg

A Positive Resampler for Monte Carlo events with negative weights

We propose the Positive Resampler to solve the problem associated with event samples from state-of-the-art predictions for scattering processes at hadron colliders typically involving a sizeable number of events contributing with negative weight. The proposed method guarantees positive weights for all physical distributions, and a correct description of all observables. A desirable side product of

Complement deposition, C4d, on platelets is associated with vascular events in systemic lupus erythematosus

OBJECTIVE: Complement components, including C4d, can be found on activated platelets, a process associated with vascular disease in SLE. We investigated whether platelet C4d (PC4d) adds additional value to traditional and known lupus-associated risk factors when identifying SLE patients with vascular disease. METHODS: This cross-sectional study included 308 well-characterized SLE patients and 308

Time-resolved site-selective imaging of predissociation and charge transfer dynamics : The CH3I B-band

The predissociation dynamics of the 6s (B2E) Rydberg state of gas-phase CH3I were investigated by time-resolved Coulomb-explosion imaging using extreme ultraviolet (XUV) free-electron laser pulses. Inner-shell ionization at the iodine 4d edge was utilized to provide a site-specific probe of the ensuing dynamics. The combination of a velocity-map imaging (VMI) spectrometer coupled with the pixel im

Future Holiday Climate Index (HCI) performance of urban and beach destinations in the Mediterranean

Tourism is a major socioeconomic contributor to established and emerging destinations in the Mediterranean region. Recent studies introducing the Holiday Climate Index (HCI) highlight the significance of climate as a factor in sustaining the competitiveness of coastal and urban destinations. The aim of this study is to assess the future HCI performance of urban and beach destinations in the greate

Slow dissolution kinetics of model peptide fibrils

Understanding the kinetics of peptide self-assembly is important because of the involvement of peptide amyloid fibrils in several neurodegenerative diseases. In this paper, we have studied the dissolution kinetics of self-assembled model peptide fibrils after a dilution quench. Due to the low concentrations involved, the experimental method of choice was isothermal titration calorimetry (ITC). We

Two Dimensional Oblique Molecular Packing within a Model Peptide Ribbon Aggregate

A10K (A=alanine, K=lysine) model peptides self-assemble into ribbon-like β-sheet aggregates. Here, we report an X-ray diffraction investigation on a flow-aligned dispersion of these self-assembly structures. The two-dimensional wide-angle X-ray scattering pattern suggests that peptide pack in a two-dimensional oblique lattice, essentially identical to the crystalline packing of polyalanine, An (fo

The ABC130 barrel module prototyping programme for the ATLAS strip tracker

For the Phase-II Upgrade of the ATLAS Detector [1], its Inner Detector, consisting of silicon pixel, silicon strip and transition radiation sub-detectors, will be replaced with an all new 100% silicon tracker, composed of a pixel tracker at inner radii and a strip tracker at outer radii. The future ATLAS strip tracker will include 11,000 silicon sensor modules in the central region (barrel) and 7,

Using SMOS soil moisture data combining CO2 flask samples to constrain carbon fluxes during 2010-2015 within a Carbon Cycle Data Assimilation System (CCDAS)

The terrestrial carbon cycle is an important component of the global carbon budget due to its large gross exchangefluxes with the atmosphere and their sensitivity to climate change. Terrestrial biosphere models showlarge uncertainties in simulating carbon fluxes, which impact global carbon budget assessments. The land surfacecarbon cycle is tightly controlled by soil moisture through plant physiol

A global Canopy Water Content product from AVHRR/Metop

Spatially and temporally explicit canopy water content (CWC) data are important for monitoring vegetation status, and constitute essential information for studying ecosystem-climate interactions. Despite many efforts there is currently no operational CWC product available to users. In the context of the Satellite Application Facility for Land Surface Analysis (LSA-SAF), we have developed an algoriSpatially and temporally explicit canopy water content (CWC) data are important for monitoring vegetationstatus, and constitute essential information for studying ecosystem-climate interactions. Despite many effortsthere is currently no operational CWC product available to users. In the context of the Satellite ApplicationFacility for Land Surface Analysis (LSA-SAF), we have developed an algorithm

Evaluation of the LSA-SAF Gross Primary Production product derived from SEVIRI/MSG data (MGPP)

The objective of this study is to describe a completely new 10-day gross primary production (GPP) product (MGPP LSA-411) based on data from the geostationary SEVIRI/MSG satellite within the LSA SAF (Land Surface Analysis SAF) as part of the SAF (Satellite Application Facility) network of EUMETSAT. The methodology relies on the Monteith approach. It considers that GPP is proportional to the absorbeThe objective of this study is to describe a completely new 10-day gross primary production (GPP) product(MGPP LSA-411) based on data from the geostationary SEVIRI/MSG satellite within the LSA SAF (Land SurfaceAnalysis SAF) as part of the SAF (Satellite Application Facility) network of EUMETSAT.The methodology relies on the Monteith approach. It considers that GPP is proportional to the absorbedph

Modelling land–atmosphere daily exchanges of NO, NH3, and CO2 in a semi-arid grazed ecosystem in Senegal

Three different models (STEP–GENDEC–NOflux, Zhang2010, and Surfatm) are used to simulateNO, CO2, and NH3 fluxes at the daily scale for 2 years(2012–2013) in a semi-arid grazed ecosystem at Dahra(152401000 N, 152505600W, Senegal, Sahel). Model resultsare evaluated against experimental results acquired duringthree field campaigns. At the end of the dry season, when thefirst rains re-wet the dry soilThree different models (STEP–GENDEC–NOflux, Zhang2010, and Surfatm) are used to simulate NO, CO2, and NH3 fluxes at the daily scale for 2 years (2012–2013) in a semi-arid grazed ecosystem at Dahra (15∘24′10′′ N, 15∘25′56′′ W, Senegal, Sahel). Model results are evaluated against experimental results acquired during three field campaigns. At the end of the dry season, when the first rains re-wet the

Mortality in first- and second-generation immigrants to Sweden diagnosed with type 2 diabetes : a 10 year nationwide cohort study

Aims/hypothesis: Non-Western immigrants to Europe are at high risk for type 2 diabetes. In this nationwide study including incident cases of type 2 diabetes, the aim was to compare all-cause mortality (ACM) and cause-specific mortality (CSM) rates in first- and second-generation immigrants with native Swedes. Methods: People living in Sweden diagnosed with new-onset pharmacologically treated type

Management of Acute Mesenteric Venous Thrombosis : A Systematic Review of Contemporary Studies

BACKGROUND AND AIMS: Acute mesenteric venous thrombosis accounts for up to 20% of all patients with acute mesenteric ischemia in high-income countries. Acute mesenteric venous thrombosis is nowadays relatively more often diagnosed with intravenous contrast-enhanced computed tomography in the portal phase than at explorative laparotomy No high-quality comparative studies between anticoagulation alo

Atomistic investigation of functionalized polyethylene-alumina interfacial strength and tensile behaviour

We study the adhesion and tensile behaviour of bi-layer interfaces comprising polyethylene, doped with carbonyl and hydroxyl functional groups emanating from ozone treatment, and - by means of density functional theory and classical atomistic modelling. The results show that the deformations are localized within the polymer and comprise chain slip, disentanglement and detachment from the substrate