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On the role of the proform-conformation for processing and intracellular sorting of human cathepsin G

The serine protease cathepsin G is synthesized during the promyelomonocytic stage of neutrophil and monocyte differentiation. After processing, including removal of an amino-terminal propeptide from the catalytically inactive proform, the active protease acquires a mature conformation and is stored in azurophil granules. To investigate the importance of the proform-conformation for targeting to gr

Nanoparticles of iridium and other platinum group elements identified in Chicxulub asteroid impact spherules – Implications for impact winter and profound climate change

The Chicxulub asteroid that ended the Cretaceous Era ∼66.05 million years ago caused a prolonged time of global darkness – the impact winter – leading to mass extinctions. Elements from the asteroid, including the platinum group elements (PGEs) osmium, iridium and platinum are known from the globally distributed boundary clay but their carrier elements have so far been unknown. We identify, for th

Onset of pore collapse and dilatancy in porous sandstone under true triaxial compression : Experimental observation and micromechanical modeling

We present new true triaxial compression data obtained in the ductile regime on Bleurswiller sandstone. The deformed samples show a range of failure modes qualitatively similar to what was reported by earlier experimental studies performed in conventional conditions (axisymmetric compression). In particular, visual inspection and X-ray Computed Tomography imaging reveal compaction localization in

Bayesian learning with Gaussian processes for low-dimensional representations of time-dependent nonlinear systems

This work presents a data-driven method for learning low-dimensional time-dependent physics-based surrogate models whose predictions are endowed with uncertainty estimates. We use the operator inference approach to model reduction that poses the problem of learning low-dimensional model terms as a regression of state space data and corresponding time derivatives by minimizing the residual of reduc

Intense Extreme Ultraviolet Pulses for Attosecond Pump-Probe Experiments

Attosecond science enables the study of ultrafast dynamics on atomic scales, providing fundamental insights into light–matter interaction. This thesis work aims to advance the development and application of an attosecond light source capable of delivering extreme ultraviolet (XUV) pulses with exceptionally high intensity.High-order harmonic generation (HHG) is a nonlinear process where a strong la

Study of initial notch wear during turning of stainless steel with CVD Al2O3/Ti(C,N) coated cemented carbide tools

Notch wear often determines tool life when machining stainless steel. Chemical Vapour Deposited (CVD) Al2O3/Ti(C,N) coated cemented carbide tools are the first recommendation for turning of stainless steel. The CVD coating plays a vital role in reducing and delaying tool wear progress. Hence, it is essential to understand the interaction between the initiation of notch wear and the coating degrada

Impact of cutting tool and workpiece material on initial notch wear in turning

In stainless steel turning, cutting tool life is often limited by excessive localised damage at the depth of cut line, known as notch wear. Previous research revealed that notch wear in CVD (chemical vapour deposition) Al2O3/Ti(C,N) coated WC-Co tools begins as a coating brittle fracture already after 0.3 m of cutting. This paper investigates the impact of cutting tools and workpiece materials on

Play for Democracy : facilitating a space for children’s involvement in urban development

Drawing on the quest to improve inclusion and social sustainability in urban planning process, a holistic approach on citizen participation in urban development is becoming increasingly important. One sector of society whose democratic rights remain overlooked in participatory action is children. It is therefore imperative to develop methods for processing the children’s rights to express their op

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This study examines the security measures implemented by the Pahlavi government in Iran to counter criminal and terrorist activities prior to the 1979 revolution. The research explores the challenges posed by various radical and insurgent groups, including Marxist and Islamist factions, which employed tactics such as assassinations, kidnappings, and sabotage. It also analyzes the role of the Natio

Structure of the T=13 capsid of infectious pancreatic necrosis virus (IPNV)-a salmonid birnavirus

Birnaviruses infect a broad range of vertebrate hosts, including fish and birds, and cause substantial economic losses in the fishery and livestock industries. The infectious pancreatic necrosis virus (IPNV), an aquabirnavirus, specifically infects salmonids. While structures on T=1 subviral particles of the birnaviruses, including IPNV, have been studied, structural insights into the infectious T

Real-time data processing for serial crystallography experiments

We report the use of streaming data interfaces to perform fully online data processing for serial crystallography experiments, without storing intermediate data on disk. The system produces Bragg reflection intensity measurements suitable for scaling and merging, with a latency of less than 1 s per frame. Our system uses the CrystFEL software in combination with the ASAP::O data framework. In a se

Structure of the Lysinibacillus sphaericus Tpp49Aa1 pesticidal protein elucidated from natural crystals using MHz-SFX.

The Lysinibacillus sphaericus proteins Tpp49Aa1 and Cry48Aa1 can together act as a toxin toward the mosquito Culex quinquefasciatus and have potential use in biocontrol. Given that proteins with sequence homology to the individual proteins can have activity alone against other insect species, the structure of Tpp49Aa1 was solved in order to understand this protein more fully and inform the desig

Diffraction data from aerosolized Coliphage PR772 virus particles imaged with the Linac Coherent Light Source

Single Particle Imaging (SPI) with intense coherent X-ray pulses from X-ray free-electron lasers (XFELs) has the potential to produce molecular structures without the need for crystallization or freezing. Here we present a dataset of 285,944 diffraction patterns from aerosolized Coliphage PR772 virus particles injected into the femtosecond X-ray pulses of the Linac Coherent Light Source (LCLS). Ad

Electrospray sample injection for single-particle imaging with x-ray lasers

The possibility of imaging single proteins constitutes an exciting challenge for x-ray lasers. Despite encouraging results on large particles, imaging small particles has proven to be difficult for two reasons: not quite high enough pulse intensity from currently available x-ray lasers and, as we demonstrate here, contamination of the aerosolized molecules by nonvolatile contaminants in the soluti

Correlations in Scattered X-Ray Laser Pulses Reveal Nanoscale Structural Features of Viruses

We use extremely bright and ultrashort pulses from an x-ray free-electron laser (XFEL) to measure correlations in x rays scattered from individual bioparticles. This allows us to go beyond the traditional crystallography and single-particle imaging approaches for structure investigations. We employ angular correlations to recover the three-dimensional (3D) structure of nanoscale viruses from x-ray

Coherent soft X-ray diffraction imaging of coliphage PR772 at the Linac coherent light source

Single-particle diffraction from X-ray Free Electron Lasers offers the potential for molecular structure determination without the need for crystallization. In an effort to further develop the technique, we present a dataset of coherent soft X-ray diffraction images of Coliphage PR772 virus, collected at the Atomic Molecular Optics (AMO) beamline with pnCCD detectors in the LAMP instrument at the

Coherent diffraction of single Rice Dwarf virus particles using hard X-rays at the Linac Coherent Light Source

Single particle diffractive imaging data from Rice Dwarf Virus (RDV) were recorded using the Coherent X-ray Imaging (CXI) instrument at the Linac Coherent Light Source (LCLS). RDV was chosen as it is a well-characterized model system, useful for proof-of-principle experiments, system optimization and algorithm development. RDV, an icosahedral virus of about 70 nm in diameter, was aerosolized and i

CFEL TapeDrive 2.0: a conveyor belt-based sample-delivery system for multi-dimensional serial crystallography

Serial crystallography (SX) at both X-ray free-electron lasers (XFELs) and synchrotrons offers the possibility to collect data at non-cryogenic temperature almost radiation damage free and enables time-resolved crystallography of irreversible reactions. The necessary steady delivery of new micron-sized crystals of biological macromolecules sets it apart from traditional single crystal macromolecul

Valuing drought impact mitigation on ecosystem services in a Mediterranean country

Drought is a complex natural hazard increasing in frequency, duration, and severity worldwide. Although droughts cause both market and non-market impacts, the latter suffers from a dearth of economic studies quantifying their magnitude. In this paper, we investigated how droughts affect selected ecosystem services expected to result in welfare losses in Spain. This study is aimed at quantifying an

Shock treatment in a cohort of Scandinavian intensive care units in 2014

BACKGROUND: Shock is common in intensive care units, and treatment includes fluids, vasopressor and/or inotropic drugs, guided by hemodynamic monitoring. The aim of this study was to identify current practice for treatment of shock in Scandinavian intensive care units.METHODS: Seven-day inception cohort study in 43 intensive care units in Scandinavia. Patients ≥ 15 years old receiving more than 4