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The transformation by catalysis of prebiotic chemical systems to useful biochemicals : A perspective based on IR spectroscopy of the primary chemicals II. Catalysis and the building of RNA

Having found that carbonyl sulfide (COS), works well as a catalyst in the transformation of amino acids to polypeptides, we have now tested COS as a catalyst also for the formation of substances that might be thought of as partners in the building of RNA. The model used was selective energy transfer (SET). This model implies that a certain number of vibrational quanta are donated from the catalyst

Effects of ambient pressure and nozzle diameter on ignition characteristics in diesel spray combustion

Numerical simulations are performed to investigate the effects of ambient density (ρam) and nozzle diameter (Dnoz) on the ignition characteristic of diesel spray combustion under engine-like conditions. A total of nine cases which consist of different ρam of 14.8, 30.0, and 58.5 kg/m3 and different Dnoz of 100, 180, and 363 μm are considered. The results show that the predicted ignition delay time

Realization of Ultrahigh Quality InGaN Platelets to be Used as Relaxed Templates for Red Micro-LEDs

In this work, arrays of predominantly relaxed InGaN platelets with indium contents of up to 18%, free from dislocations and offering a smooth top c-plane, are presented. The InGaN platelets are grown by metal-organic vapor phase epitaxy on a dome-like InGaN surface formed by chemical mechanical polishing of InGaN pyramids defined by 6 equivalent {101¯ 1} planes. The dome-like surface is f

The micrometeorite flux to Earth during the earliest Paleogene reconstructed in the Bottaccione section (Umbrian Apennines), Italy

Based on sediment-dispersed extraterrestrial spinel grains in the Bottaccione limestone section in Italy, we reconstructed the micrometeorite flux to Earth during the early Paleocene. From a total of 843 kg of limestone, 86 extraterrestrial spinel grains (12 grains > 63 μm, and 74 in the 32–63 μm fraction) have been recovered. Our results indicate that the micrometeorite flux was not elevated duri

A Micro-Simulation Study of the Generalized Proportional Allocation Traffic Signal Control

We study the problem of controlling phase activations for signalized junctions in an urban transportation network using local feedback information consisting of measures of the queue-lengths at the incoming lanes of each junction. Our focus is on the validation and performance evaluation through micro-simulations of the recently proposed Generalized Proportional Allocation (GPA) controller. Previo

Comparative study on the adiabatic film cooling performances with elliptical or super-elliptical holes of various length-to-width ratios

In this study, the effects of elliptical and super-elliptical film holes on the adiabatic film cooling effectiveness under a density ratio of 2 and blowing ratios 0.5 and 1 are studied. Five different cases are designed by considering various length-to-width ratios and the baseline is the model with cylindrical film hole. The DES with the Realizable k-ε model is adopted for the five cases to inves

Increases in bioactive IGF do not parallel increases in total IGF-I during growth hormone treatment of children born SGA

Background: Some children born small for gestational age (SGA) experience supra-physiological insulin-like growth factor-I (IGF-I) concentrations during GH treatment. However, measurements of total IGF-I concentrations may not reflect the bioactive fraction of IGF-I which reaches the IGF-I receptor at target organs. We examined endogenous IGF-bioactivity using an IGF-I kinase receptor activation (

Local markets and price premiums—The case of the establishment of the Stockholm fish auction

The promotion of locally produced food has been a growing marketing trend in recent years. Locally produced food is associated with positive values such as environmental benefits, fresher and safer products as well as contributing to building closer ties between people in local communities. We use a case study were a local fish auction was established in the Stockholm area in Sweden with the aim t

Aligning the good practice mask with the objectives of the European innovation partnership on active and healthy ageing

The reference sites of the European Innovation Partnership on Active and Healthy Ageing (EIP on AHA) were renewed in 2019. The DG Santé good practice Mobile Airways Sentinel networK was reviewed to meet the objectives of the EIP on AHA. It included 1) Management of care process, 2) Blueprint of digital transformation, 3) EIP on AHA, innovation to market, 4) Community for monitoring and assessment

Local electronic structure of stable monolayers of α-MoO3−x grown on graphite substrate

We report on van der Waals epitaxy of two-dimensional (2D) molybdenum trioxide (MoO3−x) with monolayer thickness directly grown on highly oriented pyrolytic graphite by thermal evaporation under ultrahigh vacuum. The chemical composition, electronic and crystalline lattice structures of the mono-and few-layer MoO3−x sheets are analysed. Using scanning tunnelling microscopy and spectroscopy, we inv

Dehydrogenation mechanisms of liquid organic hydrogen carriers over Pt, Pd, Rh, and Ni surfaces : Cyclohexane as a model compound

In order to make a better understanding of dehydrogenation mechanisms of liquid organic hydrogen carriers, cyclohexane was selected as a model compound to carry out its decomposition studies over Pt(1 1 1), Pd(1 1 1), Rh(1 1 1), and Ni(1 1 1) surfaces via periodic density functional theory calculations. The adsorption geometries and adsorption energies of reaction intermediates were presented. Sim

Roof cavity dust as an exposure proxy for extreme air pollution events

Understanding exposure to air pollution during extreme events such as fire emergencies is critical for assessing their potential health impacts. However, air pollution emergencies often affect places without a network of air quality monitoring and characterising exposure retrospectively is methodologically challenging due to the complex behaviour of smoke and other air pollutants. Here we test the

Family patterns of arterial stiffness across three generations in the Malmö Offspring Study

Background:Central haemodynamics have in recent years emerged as a promising predictor of cardiovascular health and risk of cardiovascular disease (CVD). Central haemodynamics are affected early in the development of vascular aging and contributes to target organ damage. Carotid-femoral pulse wave velocity (c-f PWV), augmentation index (Aix) and central SBP (cSBP) are variables that reflect arteri

Personality- and size-related metabolic performance in invasive round goby (Neogobius melanostomus)

Differences between individuals in behavioral type (i.e. animal personality) are ecologically and evolutionarily important because they can have significant effects on fitness components such as growth and predation risk. In the present study we are used the invasive round goby (Neogobius melanostomus) from an established population in controlled experiments to examine the relationships among pers

Expression and activity of critical digestive enzymes during early larval development of the veined rapa whelk, Rapana venosa (Valenciennes, 1846)

Metamorphosis is a vital developmental event in the life cycle of molluscs and involves extensive morphological and physiological changes. Remodeling of the digestive system is suggested to occur anticipatorily to enable the larva to shift its diet (from filter feeding on microalgae to feeding on small bivalves) after metamorphosis. Changes in the profiles and activities of digestive enzymes, the

Nanoclay-induced bacterial flocculation for infection confinement

Effects of size and charge of anionic nanoclays on their interactions with bacteria-mimicking lipid membranes, bacterial lipopolysaccharide (LPS), and Gram-negative bacteria were investigated using ellipsometry, dynamic light scattering, ζ-potential measurements, and confocal microscopy combined with Live/Dead staining. Based on particle size and charge density, three different anionic hectorite n

Highly sensitive and stable fructose self-powered biosensor based on a self-charging biosupercapacitor

Herein, we present an alternative approach to obtain a highly sensitive and stable self-powered biosensor that was used to detect D-fructose as proof of concept.In this platform, we perform a two-step process, viz. self-charging the biosupercapacitor for a constant time by using D-fructose as fuel and using the stored charge to realize the detection of D-fructose by performing several polarization

Barriers, enablers and market governance : A review of the policy landscape for repair of consumer electronics in the EU and the U.S.

Many strategies have been proposed to support the transition to a Circular Economy (CE). In most cases, circular design and product life-extension practices specify repair as an essential element. In both the EU and the U.S., policymakers are attempting to increase the amount of repairs made, through the introduction of recent EU Ecodesign regulation changes and proposed US Right to Repair legisla