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Phosphatic bromalites and microfossils from the Furongian (Cambrian) of northern Poland (Baltica) and palaeobiological implications
The Furongian Słowińska Formation in Poland yielded minute three-dimensionally preserved, phosphatic fossils. Based on shape and structure, two distinct types are identified. The first type comprises sinuously folded, coiled, or spiral string-shaped specimens, interpreted as faecal material, coprolites. The specimens measure between less than one and two mm, the strings being long and against thei
Measurements of laminar burning velocities and an improved kinetic model of methyl isopropyl ketone
Methyl isopropyl ketone (MIPK) is the simplest branched ketone and a promising biofuel. In this work, laminar burning velocities (SL) of MIPK + air flames were measured using the heat flux method at atmospheric pressure, over initial mixture temperatures of 298–358 K and equivalence ratios of 0.7–1.4. With the help of the temperature dependence of the SL, data inconsistency between the present mea
Content, interest and the role of engagement : experienced science teachers discuss
How do science teachers perceive student engagement and its importance for teaching and what strategies do they use to create it? When 21 experienced science teachers in 4 focus groups discussed these questions, they brought up behavioural aspects, but also less visible emotional and cognitive aspects, as well as reciprocal aspects of teacher and student engagement. One teacher described engagemen
EDGE : the shape of dark matter haloes in the faintest galaxies
Collisionless dark matter only (DMO) structure formation simulations predict that dark matter (DM) haloes are prolate in their centres and triaxial towards their outskirts. The addition of gas condensation transforms the central DM shape to be rounder and more oblate. It is not clear, however, whether such shape transformations occur in 'ultra-faint' dwarfs, which have extremely low baryon fractio
Development of multi-element monolithic germanium detectors for X-ray detection at synchrotron facilities
In past years efforts have concentrated on the development of arrays of Silicon Drift Detectors for X-ray spectroscopy. This is in stark contrast to the little effort that has been devoted to the improvement of germanium detectors, in particular for synchrotron applications. Germanium detectors have better energy resolution and are more efficient in detecting high energy photons than silicon detec
Environmental impacts of shared mobility : a systematic literature review of life-cycle assessments focusing on car sharing, carpooling, bikesharing, scooters and moped sharing
Evidence about the environmental impacts of shared mobility is fragmented and scattered. In this article a systematic literature review is presented. The review focuses on assessments that use Life-Cycle Assessment to quantify the environmental impacts of car sharing, carpooling, bikesharing, and scooter/moped sharing. The results of these assessments were analyzed, as well as the factors that inf
Structural investigation of ultra-low resistance deeply recessed sidewall ohmic contacts for AlGaN/GaN HEMTs based on Ti/Al/Ti-metallization
This study presents a novel approach to forming low-resistance ohmic contacts for AlGaN/GaN HEMTs. The optimized contacts exhibit an outstanding contact resistance of approximately 0.15 Ω·mm. This is achieved by firstly recessing the barrier of the heterostructure to a depth beyond the channel. In this way, the channel region is exposed on the sidewall of the recess. The coverage of the Ti/Al/Ti o
Real-time visualization of smoke for fire safety engineering applications
Visibility in smoke is a key aspect in terms of safe egress in various fire related situations. Due to the hazardous nature of fire induced smoke, it is hard to study human behaviour under such conditions, but recent development within the field of virtual reality (VR) has enabled exposure to many different hazardous conditions while remaining relatively safe. However, to obtain valid results from
Effects of topping and non-topping on growth-regulating hormones of flue-cured tobacco (Nicotiana tabacum L.)—a proteomic analysis
Introduction: Until now, the mechanism underlying the impact of topping on hormone regulation in tobacco plants remains unclear, and most studies investigating the hormone signaling pathways in plants rely on genes or transcriptional pathways. Methods: This study examines the regulatory mechanisms of hormones in the roots and leaves of tobacco plants with and without topping at the protein level.
Simulation of breast lesions based upon fractal Perlin noise
Purpose: Steadily increasing use of computational/virtual phantoms in medical physics has motivated expanding development of new simulation methods and data representations for modelling human anatomy. This has emphasized the need for increased realism, user control, and availability. In breast cancer research, virtual phantoms have gained an important role in evaluating and optimizing imaging sys
Abdominal compression as motion management for stereotactic radiotherapy of ventricular tachycardia
Background and purpose: Stereotactic body radiotherapy (SBRT) has emerged as a promising treatment for patients with ventricular tachycardia (VT) who do not respond to standard treatments. However, the management of respiratory motion during treatment remains a challenge. This study aimed to investigate the effect of abdominal compression (AC) on respiratory induced motion in the heart. Materials
Phase transitions of ionic fluids in nanoporous electrodes
Abstract: In this work, we utilise grand canonical Metropolis Monte Carlo simulations, to establish pore-induced freezing of restricted primitive model fluids. A planar pore model is utilised, with walls that are initially neutral, and either non-conducting or perfectly conducting. The phase of the confined electrolyte (solid/fluid) displays an oscillatory dependence on surface separation, in narr
On the thermal conductivity anisotropy in wurtzite GaN
GaN-based power devices operating at high currents and high voltages are critically affected by the dissipation of Joule heat generated in the active regions. Consequently, knowledge of GaN thermal conductivity is crucial for effective thermal management, needed to ensure optimal device performance and reliability. Here, we present a study on the thermal conductivity of bulk GaN in crystallographi
Probing cellulose–solvent interactions with self-diffusion NMR : Onium hydroxide concentration and co-solvent effects
The molecular self-diffusion coefficients were accessed, for the first time, in solutions of microcrystalline cellulose, dissolved in 30 wt% and 55 wt% aqueous tetrabutylammonium hydroxide, TBAH (aq), and in mixtures of 40 wt% TBAH (aq) with an organic co-solvent, dimethylsulfoxide (DMSO), through pulsed field gradient stimulated echo NMR measurements. A two-state model was applied to estimate α (
Phase II LEAP-004 Study of Lenvatinib Plus Pembrolizumab for Melanoma with Confirmed Progression on a Programmed Cell Death Protein-1 or Programmed Death Ligand 1 Inhibitor Given as Monotherapy or in Combination
PURPOSE Effective treatments are needed for melanoma that progresses on inhibitors of programmed cell death protein-1 (PD-1) or its ligand (PD-L1). We conducted the phase II LEAP-004 study to evaluate the combination of the multikinase inhibitor lenvatinib and the PD-1 inhibitor pembrolizumab in this population (ClinicalTrials.gov identifier: NCT03776136).METHODSEligible patients with unresectable
On the role of internationalization of firm-level corporate governance : The case of audit committees
Research Question/Issue: Motivated by the agency theory and the findings of linguistic studies, we analyze the association between the internationalization of a firm's audit committee and its corporate governance. Research Findings/Insights: Based on data from 2159 publicly traded European firms from 15 countries for the period 2000–2018, we find that firms with foreign directors on their audit co
Deciphering microbiomes dozens of meters under our feet and their edaphoclimatic and spatial drivers
Microbes inhabiting deep soil layers are known to be different from their counterpart in topsoil yet remain under investigation in terms of their structure, function, and how their diversity is shaped. The microbiome of deep soils (>1 m) is expected to be relatively stable and highly independent from climatic conditions. Much less is known, however, on how these microbial communities vary along cl
The microbial biodiversity at the archeological site of Tel Megiddo (Israel)
Introduction: The ancient city of Tel Megiddo in the Jezreel Valley (Israel), which lasted from the Neolithic to the Iron Age, has been continuously excavated since 1903 and is now recognized as a World Heritage Site. The site features multiple ruins in various areas, including temples and stables, alongside modern constructions, and public access is allowed in designated areas. The site has been
Taphonomic experiments reveal authentic molecular signals for fossil melanins and verify preservation of phaeomelanin in fossils
Melanin pigments play a critical role in physiological processes and shaping animal behaviour. Fossil melanin is a unique resource for understanding the functional evolution of melanin but the impact of fossilisation on molecular signatures for eumelanin and, especially, phaeomelanin is not fully understood. Here we present a model for the chemical taphonomy of fossil eumelanin and phaeomelanin ba