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Size-dependent melting of silica-encapsulated gold nanoparticles

We report on the size dependence of the melting temperature of silica-encapsulated gold nanoparticles. The melting point was determined using differential thermal analysis (DTA) coupled to thermal gravimetric analysis (TGA) techniques. The small gold particles, with sizes ranging from 1.5 to 20 nm, were synthesized using radiolytic and chemical reduction procedures and then coated with porous sili

Bottom-up and top-down drivers of herbivory on Arabica coffee along an environmental and management gradient

While sustainable agriculture relies on natural pest control, we lack insights into the relative importance of bottom-up and top-down factors on pest levels, especially along broad environmental and management gradients. To this aim, we focused on bottom-up and top-down control of herbivore damage in sixty sites in the centre of origin of Arabica coffee in southwestern Ethiopia, where coffee grows

Phonon transport and thermoelectricity in defect-engineered InAs nanowires

There have been reports of improvements in the thermoelectric figure of merit through the use of nanostructured materials to suppress the lattice thermal conductivity. Here, we report on a fundamental study of the combined effects of defect planes and surface scattering on phonon transport and thermoelectric properties of defect-engineered InAs nanowires. A microfabricated device is employed to me

Public preference for sustainable land use policies – Empirical results from multinomial logit model analysis

Public preferences for sustainable land use policy instruments and the motivations behind such preferences are important to make appropriate policies. Based on survey data (n = 309) from northeastern Somalia, we examined preferences for a set of land use policy instruments relative to no policy (i.e. the current status quo) and how cultural worldviews predict such preferences. We used a multinomia

Volcanic temperature changes modulated volatile release and climate fluctuations at the end-Triassic mass extinction

Emplacement of the Central Atlantic Magmatic Province (CAMP) is thought to have triggered global environmental changes and the end-Triassic mass extinction (ETE). However, the mechanisms linking volcanism and environmental change are unclear. Here we provide new insight into these linkages by measuring the abundance of both sedimentary five- to six-ring polycyclic aromatic hydrocarbons (PAHs) and

Early and late-onset syncope : insight into mechanisms

AIMS: Unexplained syncope is an important clinical challenge. The influence of age at first syncope on the final syncope diagnosis is not well studied.METHODS AND RESULTS: Consecutive head-up tilt patients (n = 1928) evaluated for unexplained syncope were stratified into age groups

Multi-scattering software part II : Experimental validation for the light intensity distribution

This article, Part II of an article series on GPU-accelerated Monte Carlo simulation of photon transport through turbid media, focuses on the validation of the online software Multi-Scattering. While Part I detailed the implementation of the computational model, simulated and experimental results are now compared for the distribution of the scattered light intensity. The scattering phantoms prepar

Chaperones mainly suppress primary nucleation during formation of functional amyloid required for bacterial biofilm formation

Unlike misfolding in neurodegenerative diseases, aggregation of functional amyloids involved in bacterial biofilm, e.g. CsgA (E. coli) and FapC (Pseudomonas), is carefully regulated. However, it is unclear whether functional aggregation is inhibited by chaperones targeting pathological misfolding and if so by what mechanism. Here we analyze how four entirely different human chaperones or protein m

Human impacts and their interactions in the Baltic Sea region

Coastal environments, in particular heavily populated semi-enclosed marginal seas and coasts like the Baltic Sea region, are strongly affected by human activities. A multitude of human impacts, including climate change, affect the different compartments of the environment, and these effects interact with each other. As part of the Baltic Earth Assessment Reports (BEAR), we present an inventory and

Azimuthal correlations of high transverse momentum jets at next-to-leading order in the parton branching method

The azimuthal correlation, Δ ϕ12, of high transverse momentum jets in pp collisions at s=13 TeV is studied by applying PB-TMD distributions to NLO calculations via MCatNLO together with the PB-TMD parton shower. A very good description of the cross section as a function of Δ ϕ12 is observed. In the back-to-back region of Δ ϕ12→ π, a very good agreement is observed with the PB-TMD Set 2 distributio

Signature of femtosecond laser-induced superfluorescence from atomic hydrogen

Cavity-free lasing generation from gas constituents has been studied in the past decade since it promises great potentials in remote sensing and optical diagnostics techniques. Here we report on experimental investigations of temporal characteristics of H-atom lasing emission at 656 nm by examining the dependences of its durations and delays on the pump-laser-pulse energies. An indirect measuremen

Relativistic time-dependent configuration-interaction singles method

In this work, a derivation and implementation of the relativistic time-dependent configuration-interaction singles (RTDCIS) method is presented. Various observables for krypton and xenon atoms obtained by RTDCIS are compared with experimental data and alternative relativistic calculations. This includes energies of occupied orbitals in the Dirac-Fock ground state, Rydberg state energies, Fano reso

High-Efficiency Expression and Purification of DNAJB6b Based on the pH-Modulation of Solubility and Denaturant-Modulation of Size

The chaperone DNAJB6b delays amyloid formation by suppressing the nucleation of amyloid fibrils and increases the solubility of amyloid-prone proteins. These dual effects on kinetics and equilibrium are related to the unusually high chemical potential of DNAJB6b in solution. As a consequence, the chaperone alone forms highly polydisperse oligomers, whereas in a mixture with an amyloid-forming prot

Forming molecular states with hadronic rescattering

A method for modelling the prompt production of molecular states using the hadronic rescattering framework of the general-purpose Pythia event generator is introduced. Production cross sections of possible exotic hadronic molecules via hadronic rescattering at the LHC are calculated for the χc1(3872) resonance, a possible tetraquark state, as well as three possible pentaquark states, Pc+(4312), Pc

Hadron interactions for arbitrary energies and species, with applications to cosmic rays

The Pythia event generator is used in several contexts to study hadron and lepton interactions, notably p p and p p ¯ collisions. In this article we extend the hadronic modelling to encompass the collision of a wide range of hadrons h with either a proton or a neutron, or with a simplified model of nuclear matter. To this end we model hp total and partial cross sections as a function of energy, an

Cold-induced anesthesia impairs path integration memory in dung beetles

Path integration is a general mechanism used by many animals to maintain an updated record of their position in relation to a set reference point.1–11 To do this, they continually integrate direction and distance information into a memorized home vector. What remains unclear is how this vector is stored, maintained, and utilized for successful navigation. A recent computational model based on the

Freshwater salinisation : a research agenda for a saltier world

The widespread salinisation of freshwater ecosystems poses a major threat to the biodiversity, functioning, and services that they provide. Human activities promote freshwater salinisation through multiple drivers (e.g., agriculture, resource extraction, urbanisation) that are amplified by climate change. Due to its complexity, we are still far from fully understanding the ecological and evolution

Phenotypic plasticity is aligned with phenological adaptation on both micro- and macroevolutionary timescales

In seasonally variable environments, phenotypic plasticity in phenology may be critical for adaptation to fluctuating environmental conditions. Using an 18-generation longitudinal dataset from natural damselfly populations, we show that phenology has strongly advanced. Individual fitness data suggest this is likely an adaptive response towards a temperature-dependent optimum. A laboratory experime

Fish resist temptation from junk food : state-dependent diet choice in reproductive Atlantic cod Gadus morhua facing seasonal fluxes of lipid-rich prey

In ecological sciences, animal diets are often simplified to ‘resources' or ‘caloric quantities'. However, in the present study, we investigated the optimal foraging strategy of Atlantic cod Gadus morhua when both macro- and micro-nutritional requirements are accounted for. Proteins cannot be synthesized from fatty acids, so the proteins for gonad development must come from other dietary sources.