Towards a risk assessment framework for micro- and nanoplastic particles for human health.

Background: Human exposure to micro- and nanoplastic particles (MNPs) is inevitable but human health risk assessment remains challenging for several reasons. MNPs are complex mixtures of particles derived from different polymer types, which may contain plenty of additives and/or contaminants. MNPs cover broad size distributions and often have irregular shapes and morphologies.

Optical turbulence profiling at the Table Mountain Facility with the Laser Communication Relay Demonstration GEO downlink.

We report the first measurement of the atmospheric optical turbulence profile using the transmitted beam from a satellite laser communication terminal. A ring image next generation scintillation sensor (RINGSS) instrument for turbulence profiling, as described in Tokovinin [MNRAS502, 747 (2021)10.1093/mnras/staa4049], was deployed at the NASA/Jet Propulsion Laboratory's Table Mountain Facility (TMF) in California.

Luminescence Lifetime-Based Sensing Platform Based on Cyclometalated Iridium(III) Complexes for the Detection of Perfluorooctanoic Acid in Aqueous Samples.

Luminescence lifetimes are an attractive analytical method for detection due to its high sensitivity and stability. Iridium probes exhibit luminescence with long excited-state lifetimes, which are sensitive to the local environment. Perfluorooctanoic acid (PFOA) is listed as a chemical of high concern regarding its toxicity and is classified as a "forever chemical".

Reliable Surface Analysis Data of Nanomaterials in Support of Risk Assessment Based on Minimum Information Requirements.

The minimum information requirements needed to guarantee high-quality surface analysis data of nanomaterials are described with the aim to provide reliable and traceable information about size, shape, elemental composition and surface chemistry for risk assessment approaches. The widespread surface analysis methods electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectrometry (SIMS) were considered. The complete analysis sequence from sample preparation, over measurements, to data analysis and data format for reporting and archiving is outlined.

Preparation of Nanoparticles for ToF-SIMS and XPS Analysis.

Nanoparticles have gained increasing attention in recent years due to their potential and application in different fields including medicine, cosmetics, chemistry, and their potential to enable advanced materials. To effectively understand and regulate the physico-chemical properties and potential adverse effects of nanoparticles, validated measurement procedures for the various properties of nanoparticles need to be developed. While procedures for measuring nanoparticle size and size distribution are already established, standardized methods for analysis of their surface chemistry are not yet in place, although the influence of the surface chemistry on nanoparticle properties is undisputed.

Considerations for upscaling individual effects of wind energy development towards population-level impacts on wildlife.

The expansion of wind energy poses challenges to policy- and decision-makers to address conflicts with wildlife. Conflicts are associated with impacts of existing and planned projects on wildlife, and associated difficulties of prediction where impacts are subject to considerable uncertainty. Many post-construction studies have demonstrated adverse effects on individuals of various bird and bat species.

Quantifying avian avoidance of offshore wind turbines: Current evidence and key knowledge gaps.

The risk of collision between birds and turbines is seen as one of the key issues in the planning process for offshore wind farms. In some cases, predictions of collision risk have led to projects either being withdrawn from the planning process, or refused planning consent. Despite this, the evidence base on which collision risk is assessed is extremely limited and assessments rely on models which can be highly sensitive to assumptions, notably about bird collision avoidance behaviour.

Discovery of SCH 900188: A Potent Hepatitis C Virus NS5B Polymerase Inhibitor Prodrug As a Development Candidate.

Starting from indole-based hepatitis C virus (HCV) NS5B polymerase inhibitor lead compound 1, structure modifications were performed at multiple indole substituents to improve potency and pharmacokinetic (PK) properties. Bicyclic quinazolinone was found to be the best substituent at indole nitrogen, while 4,5-furanylindole was identified as the best core. Compound 11 demonstrated excellent potency.

Structure-activity relationship (SAR) development and discovery of potent indole-based inhibitors of the hepatitis C virus (HCV) NS5B polymerase.

Starting with the indole-based C-3 pyridone lead HCV polymerase inhibitor 2, extensive SAR studies were performed at different positions of the indole core. The best C-5 groups were found to be compact and nonpolar moieties and that the C-6 attachments were not affecting potency. Limited N-1 benzyl-type substituent studies indicated that the best substitutions were fluoro or methyl groups at 2' or 5' positions of the benzyl group.

Observation of nonlinear self-trapping of broad beams in defocusing waveguide arrays.

We demonstrate experimentally the localization of broad optical beams in periodic arrays of optical waveguides with defocusing nonlinearity. This observation in optics is linked to nonlinear self-trapping of Bose-Einstein-condensed atoms in stationary periodic potentials being associated with the generation of truncated nonlinear Bloch states, existing in the gaps of the linear transmission spectrum. We reveal that unlike gap solitons, these novel localized states can have an arbitrary width defined solely by the size of the input beam while independent of nonlinearity.

Focusing-to-defocusing crossover in nonlinear periodic structures.

We demonstrate experimentally a transition from nonlinear beam trapping to defocusing in a two-dimensional periodic photonic structures by varying the modulation depth of the lattice. The observed effect illustrates the fundamental crossover from discrete to cw transport mechanisms. At the threshold modulation, the output beam is highly sensitive to refractive index and power variations, which can be potentially applied for high-sensitivity refractive index or temperature sensing.

Observation of two-dimensional nonlocal gap solitons.

We demonstrate, both theoretically and experimentally, the existence of nonlocal gap solitons in two-dimensional periodic photonic structures with defocusing thermal nonlinearity. We employ liquid-infiltrated photonic crystal fibers and show how the system geometry can modify the effective response of a nonlocal medium and the properties of two-dimensional gap solitons.

Tunable diffraction and self-defocusing in liquid-filled photonic crystal fibers.

We suggest and demonstrate a novel platform for the study of tunable nonlinear light propagation in two-dimensional discrete systems, based on photonic crystal fibers filled with high index nonlinear liquids. Using the infiltrated cladding region of a photonic crystal fiber as a nonlinear waveguide array, we experimentally demonstrate highly tunable beam diffraction and thermal self-defocusing, and realize a compact all-optical power limiter based on a tunable nonlinear response.

Effect of biostimulation on uterine involution, early ovarian activity and first postpartum estrous cycle in beef cows.

The objective was to determine the effect of biostimulation (bull-exposure) on uterine involution (UI), plasma progesterone concentration (P4), size of largest follicle (LF), number of follicles larger than 5 mm ( F > or = 5 ), presence of fluid in uterine lumen (PF), presence of luteal tissue (LT), and length of the first estrous cycle postpartum (LEC). Ninety Angus cows with calves were allocated by parity and body frame into three groups (30 per group) 1 week postpartum. Two groups were exposed to bulls (BE) and one non-exposed group (NE) served as a control.

Systematic investigations of the influence of molecular structure on the transport of peptides across cultured alveolar cell monolayers.

Purpose: To determine how the structures of peptides influence their alveolar permeability.

Methods: The studies were performed using 14 synthetic 'model' peptides, labelled with a novel, non-intrusive amino acid fluorophore, and their transport studied using rat alveolar cell monolayers cultured on permeable supports.

Results: The passage of the peptides across the epithelial cell monolayers is shown to be primarily paracellular, with an inverse dependence on molecular size, and an enhanced flux observed for cationic peptides.

Use of alveolar cell monolayers of varying electrical resistance to measure pulmonary peptide transport.

The apparent permeability coefficient (P(app)) of two fluorescently tagged model hydrophilic peptides, acXASNH(2) and acXAS(GAS)(7)NH(2), and (14)C-mannitol across monolayers of cultured rat alveolar epithelial cells of varying transepithelial electrical resistance (TER) has been examined. In line with their design features, the peptides were not degraded under the conditions of the test. Furthermore, no concentration dependence of transport of the tripeptide acXASNH(2) was observed over the concentration range studied, nor was any directional transport seen for either of the model peptides, indicating that under the conditions of the test they were not substrates for any transporters or efflux pumps.

Angiotensinogen and blood pressure among blacks: findings from a community survey in Jamaica.

Objective: To examine the association between blood pressure, angiotensinogen levels, angiotensin converting enzyme activity and polymorphisms of the angiotensinogen and angiotensin converting enzyme genes in a population-based sample.

Method: Five hundred participants were recruited in a house-to-house survey of three communities in metropolitan areas of Kingston and St Andrew, in Jamaica. Demographic data, anthropometric and blood pressure measurements were obtained for each participant during a brief clinic visit.