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The relationship between laser pulse duration (τ p) and stress confinement time (τ sr) was studied using acoustic-based measurements of material absorption coefficient (μ a). A numerical model was developed to simulate stress signals. Experimental photoacoustic measurements at several values of τ were performed to estimate μ a of water. A numerical deconvolution technique was implemented to overcome the limitation of conventional photoacoustics, resulting in up to a 30% improvement in photoacoustic-based estimates of the sample μ a.

Previous studies suggest that optimal port wine stain (PWS) laser treatment parameters require knowledge of skin characteristics such as blood vessel size, depth, and distribution. Effective and rapid imaging modalities are not widely available. In the present study, photothermal tomography (PTT) images of an in vivo hamster window model and human PWS skin were obtained and analyzed. Subtherapeutic laser light pulses at 585 and 600 nm were applied to skin surface and image sequences acquired with an infrared camera. A nonnegatively constrained conjugate gradient algorithm was used to reconstruct a PTT image of the initial temperature distribution immediately following pulsed laser irradiation. Vessel dimensions determined from PTT images of hamster window model skin compared well with those measured directly using video microscopy. PTT images of human PWS skin contained vessels with estimated diameters of 200-250 μm over a 250-320 μm depth range. Use of dual wavelength excitation (DWE) analysis allowed for imaging of shallow vessels.

PurposeWe modeled retropulsion during holmium:YAG lithotripsy on the conservation of momentum, whereby the force of ejected fragment debris off of the calculous surface should equal the force of retropulsion displacing the stone. We tested the hypothesis that retropulsion occurs as a result of ejected stone debris.Materials and methodsUniform calculous phantoms were irradiated with holmium:YAG energy in air and in water. Optical fiber diameter and pulse energy were varied. Motion of the phantom was monitored with high speed video imaging. Laser induced crater volume and geometry were characterized by optical coherence tomography. To determine the direction of plume laser burn paper was irradiated at various incident angles.ResultsRetropulsion was greater for phantoms irradiated in air versus water. Retropulsion increased as fiber diameter increased and as pulse energy increased (p

The purpose of this study was to investigate the dynamics of laser light attenuation during cryogen spray cooling (CSC). Two detection schemes were used to approximate collimated and diffuse light transmittance measurements of continuous-wave (λ = 594 nm) and pulsed (λ = 585 nm) laser light during application of short (20-100 ms duration) cryogen spurts on a glass substrate. High-speed video images were also obtained during CSC. Collimated light transmittance varied considerably during CSC. Comparison of collimated and total transmitted light detection indicated that the diffuse component was substantial. Light attenuation occurred despite transparency of the liquid cryogen layer. Light scattering by cryogen results in a diverging laser beam incident on the skin surface. Since specular reflectance at the cryogen-skin interface may differ for diffuse light, further study of light scattering during CSC is warranted. Due to the differences in optical properties of glass and skin, experiments on skin need to be performed to extrapolate our results to the clinical scenario. For dermatologic procedures such as laser port wine stain and vascular lesion removal, hair removal, and nonablative skin rejuvenation, recommended τd are 10-80 ms. This range of τd appears to be appropriate, although more studies are required to arrive at a definite conclusion. © 2002 SPIE.

Differential phase optical low coherence reflectometry (OLCR) was used to detect sub-wavelength displacements in the infrared-sensitive thoracic pit organ of Melanophila acuminata (Coleoptera: Buprestidae) upon absorption of infrared radiation at 3.39 microm. The displacement had more complex morphology but similar amplitude ( approximately 100 nm at 1 W cm(-2)) when compared to the displacement measured from the exocuticle in an alternate region on the beetle's body. In addition, a simplified finite difference model was developed to predict the temperature distribution and resultant thermal expansion in the pit organ tissue. The experimental and model results were interpreted to help clarify the mechanism by which the sensilla in the pit organ convert infrared radiation to neural signals. The results of this paper are discussed in relation to the photo-thermal-mechanical transduction hypothesis. This is the first experimental examination of the transduction mechanism in Melanophila acuminata.

Infrared laser ablation of urinary calculi was investigated as a function of wavelength to determine the relation of ablation threshold fluences, ablation depths, and optical absorption. A simple photothermal ablation model was employed to examine this relationship. Human urinary calculi composed of > 95% uric acid, > 95% cystine, > 95% calcium oxalate monohydrate (COM), and > 90% magnesium ammonium phosphate hexahydrate (MAPH) were used. Various wavelengths between 2.1 and 6.5 μm were selected to perform threshold fluence and ablation depth measurements. The laser source for this study was the tunable pulsed infrared free electron laser (FEL) at Vanderbilt University. Experimental results indicated a correlation of threshold fluence and ablation depth to the optical absorption properties of the calculi. When calculus optical absorption increased, the threshold fluences decreased. Although the ablation depths increased with calculus optical absorption, results indicated that in certain calculi the ablation depth was affected by optical attenuation through the ablation plume. These observations were in agreement with the photothermal ablation model, but fractures in striated calculi at higher optical absorptions, indicated the contribution of a photomechanical mechanism. Threshold fluences and ablation depths are a function of the wavelength dependent absorption properties of the calculi. These observations suggest that the 3-μm and 6-μm absorption bands are optimal for ablation or fragmentation of urinary calculus.

The main goal of this study was to demonstrate the feasibility of using back-side infrared imaging to estimate the spatial cryogen temperature distribution during a cryogen spurt. Calculations from numerical models showed that the front-side temperature distribution could be identified at the back side of a thin aluminum sheet. Infrared images were obtained at various timepoints during a cryogen spurt from the back side of a 800-μm aluminum sheet and the temperature distribution estimated. The temperature distribution was approximately gaussian in shape. A secondary goal was to calculate the temperature distribution in skin for two cases: 1) uniform cryogen temperature distribution, essentially representative of a 1-D geometry assumption; and 2) nonuniform distribution. At the end of a 100-ms spurt, calculations showed that, for the two cases, large discrepancies in temperatures at the surface and at a 60-μm depth were found at radii greater than 2.5 mm. These results suggest that it is necessary to consider spatial cryogen temperature gradients during cryogen spray cooling of tissue.

Background and objectiveThermal relaxation time (tau(r)) is a commonly-used parameter for estimating the time required for heat to conduct away from a directly-heated tissue region. Previous studies have demonstrated that temperature superposition can occur during multiple-pulse irradiation, even if the interpulse time is considerably longer than tau(r). The objectives of this study were (1) to analyze tissue thermal relaxation following laser-induced heating, and (2) to calculate the time required for a laser-induced temperature rise to decrease to near-baseline values.Study design/materials and methodsOne-dimensional (1-D) analytical and numerical and 2-D numerical models were designed and used for calculations of the time tau(eff) required for the peak temperature (T(peak)) to decrease to values slightly over baseline (DeltaT(base)). Temperature values included T(peak)=65 and 100 degrees C, and DeltaT(base) = 5, 10, and 20 degrees C. To generalize the calculations, a wide range of optical and thermal properties was incorporated into the models. Flattop and gaussian spatial beam profiles were also considered.Results2-D model calculations of tau(eff) demonstrated that tau(eff) (2-D) was as much as 40 times longer than tau(r). For a given combination of T(peak) and DeltaT(base), a linear relationship was calculated between tau(eff) (1-D) and tau(r) and was independent of optical and thermal properties. A comparison of 1-D and 2-D models demonstrated that 1-D models generally predicted longer values of tau(eff) than those predicted with a 2-D geometry when the laser spot diameter was equal to or less than the optical penetration depth.ConclusionRelatively simple calculations can be performed to estimate tau(eff) for known values of tau(r), T(peak) and DeltaT(base). The parameter tau(eff) may be a better estimate than tau(r) of tissue thermal relaxation during multiple-pulse laser irradiation.

An investigation of the effects of laser irradiation with a wavelength of 532 nm and pulse duration of 10 ms on whole blood was performed in vitro. Threshold radiant exposures for coagulation were quantified and transient radiometric temperatures were measured. The progression of effects with increasing radiant exposure--from evaporation to coagulation-induced light scattering to aggregated coagulum formation to ablation--is described. Results indicate that coagulation and ablation occur at temperatures significantly in excess of those assumed in previous theoretical studies. An Arrhenius rate process analysis based on hemoglobin data indicates good agreement with experimental results.

PurposeTo determine the threshold radiant exposures (J/cm2) needed for ablation or fragmentation as a function of infrared wavelengths on various urinary calculi and to determine if there is a relation between these thresholds and lithotripsy efficiencies with respect to optical absorption coefficients.Materials and methodsHuman calculi composed of uric acid, calcium oxalate monohydrate (COM), cystine, or magnesium ammonium phosphate hexahydrate (MAPH) were used. The calculi were irradiated in air with the free electron laser (FEL) at six wavelengths: 2.12, 2.5, 2.94, 3.13, 5, and 6.45 microm.ResultsThreshold radiant exposures increased as optical absorption decreased. At the near-infrared wave-lengths with low optical absorption, the thresholds were >1.5 J/cm2. The thresholds decreased below 0.5 J/cm2 for regions of high absorption for all the calculus types. Thresholds within the high-absorption regions were statistically different from those in the low-absorption regions, with P values much less than 0.05.ConclusionsOptical absorption coefficients or threshold radiant exposures can be used to predict lithotripsy efficiencies. For low ablation thresholds, smaller radiant exposures were required to achieve breakdown temperatures or to exceed the dynamic tensile strength of the material. Therefore, more energy is available for fragmentation, resulting in higher lithotripsy efficiencies.

The use of thermographic techniques has increased as infrared detector technology has evolved and improved. For laser-tissue interactions, thermal cameras have been used to monitor the thermal response of tissue to pulsed and continuous wave irradiation. It is important to note that the temperature indicated by the thermal camera may not be equal to the actual surface temperature. It is crucial to understand the limitations of using thermal cameras to measure temperature during laser irradiation of tissue. The goal of this study was to demonstrate the potential difference between measured and actual surface temperatures in a quantitative fashion using a ID finite difference model. Three ablation models and one cryogen spray cooling simulation were adapted from the literature, and predictions of radiometric temperature measurements were calculated. In general, (a) steep superficial temperature gradients, with a surface peak, resulted in an underestimation of the actual surface temperature, (b) steep superficial temperature gradients, with a subsurface peak, resulted in an overestimation, and (c) small gradients led to a relatively accurate temperature estimate.

In general, ablative laser skin resurfacing procedures have shown good short-term efficacy. However, the mchanisms underlying laser skin resurfacing remain poorly understood. We performed a quantitative study to investigate the thermal response of skin to CO2 laser irradiation. Raster scans were performed on an in vivo rat model and radiometric surface temperatures measured using a thermal camera. Temperatures approaching 400°C were measured during the scans and remained above the initial skin temperature for durations longer than ten seconds. Analysis of histology sections showed that the epidermis remained partially intact after three passess. To explain the observed trends in the temperature response and histology, the dynamics of optical and thermal parameters were investigated. Water vaporization played a key role in governing the response of the skin to subsequent laser passes. Char formation and pulse stacking altered the thermal effects.

Background and objectiveA thermal camera was used to measure surface temperatures during laser skin welding to provide feedback for optimization of the laser parameters.Study design/materials and methodsTwo-centimeter-long, full-thickness incisions were made in guinea pig skin in vitro and in vivo. India ink was applied to the incision edges, which were then mechanically apposed. Continuous-wave, 1.06-microm Nd:YAG laser radiation was scanned over the incisions, producing an effective pulse duration of approximately 100 msec. Cooling durations between scans of 1.6, 4.0, and 8.0 sec were studied in vitro. A 5-mm-diameter laser spot was used with the power kept constant at 10 W. Thermal images were obtained at 30 frames per second with a thermal camera detecting 3-5 microm radiation. Surface temperatures were recorded at 0, 1, and 6 mm from the center line of the incision.Results/conclusionsCooling durations of 1.6 and 4.0 seconds in vitro resulted in temperatures at the weld site that remained above approximately 65 degrees C for prolonged periods of time. Cooling durations of 8.0 seconds were sufficient both in vitro and in vivo to prevent a significant rise in baseline temperatures at the weld site over time.

Quantitative data regarding photothermal and damage processes during pulsed laser irradiation of blood are necessary to achieve a better understanding of laser treatment of cutaneous vascular lesions and improve numerical models. In this study, multiple experimental techniques were employed to quantify the effects of single-pulse KTP laser (λ = 532 nm, τp = 10 ms) irradiation of whole blood in vitro: high-speed temperature measurement with a thermal camera in line-scan mode (8 kHz); optical coherence tomography (for determination of coagulum morphology); and transmission measurement with a co-aligned laser beam (λ = 635 nm). Threshold radiant exposures for coagulation (4.4-5.0 J/cm2) and ablation (approximately J/cm2) were identified. Thermal camera measurements indicated threshold coagulation temperatures of 90-100 °C, and peak temperatures of up to 145 °C for sub-ablation radiant exposures. Significant changes in coagulum thickness and consistency, and a corresponding decrease in transmission, were observed with increasing radiant exposure. The Arrhenius equation was shown to produce accurate predictions of coagulation onset (using appropriate rate process coefficients). The significance of dynamic effects such as evaporative loss and dynamic changes in optical properties was indicated. Implications for numerical modeling are discussed. Most importantly, the threshold temperatures typically quoted in the literature for pulsed laser coagulation (60-70 °C) and ablation (100 °C) of blood do not match the results of this study.

The effects of cooling, laser irradiation, and laser irradiation with cooling on blood vessels were investigated with Color Doppler Optical Coherence Tomography (CDOCT). CDOCT may contribute to an understanding of the dynamics of laser-blood vessel interactions and aid in better optimization of laser parameters to be used. In this study, hamster dorsal skin flap window vessels were irradiated with a KTP laser operating at 532 nm. Irradiation sites were imaged with CDOCT prior to, during, immediately after, and several days after irradiation. KTP laser parameters were: radiant exposures in the range of 7-14 J/cm2, 3 mm spot size, and 10 ms pulse duration. Magnitude and color Doppler images provided information such as vessel size, depth, and changes in blood flow velocity. Vessel constriction, temporary occlusion, and changes in flow were frequent results of laser irradiation visualized with CDOCT. In addition, the effects of cooling alone were imaged with CDOCT and its effects on blood vessel flow and morphology were investigated before and after laser irradiation.

Background and objectiveSeveral published reports describe the benefits of using the carbon dioxide laser for cutaneous resurfacing. The mechanisms on which skin resurfacing work are still not completely understood. This study was performed to obtain quantitative and qualitative information describing the thermal response of skin during high-energy, short-pulsed CO2 laser irradiation.Study design/materials and methodsA Tissue Technologies TruPulse CO2 laser was used to irradiate an in vivo rat model. The laser parameters that were used were a 100-micros pulse width, a 1-Hz repetition rate, a 3 mm x 3 mm square spot size, and 2.4 J/cm2 and 3.9 J/cm2 radiant exposures. A 3-5 microm thermal camera was used to obtain temperature information during irradiation. Single spots were irradiated with one pulse, and the temperature-time history was obtained. In a different experiment, 15 pulses were applied to single spots, and both thermal and video images were obtained.ResultsIrradiation with one pulse at 2.4 J/cm2 and 3.9 J/cm2 led to peak temperatures >100 degrees C. The temperature relaxation time was approximately 25-150 ms. Multiple-pulse irradiation at 2.4 J/cm2 led to a slight rise in the peak temperature with each pulse. At 3.9 J/cm2, the peak temperature increased with successive pulses until pulse 10, after which the peak temperature oscillated between 300 and 400 degrees C. Video images showed concurrent burning events that occurred during pulses 10-15.ConclusionTemperatures >100 degrees C were measured during CO2 laser irradiation of skin. Pulse stacking can lead to peak temperatures approaching 400 degrees C and to tissue charring with as few as three stacked pulses. It is crucial for the physician to manipulate the laser handpiece at parameters with which he or she can avoid pulse overlap.

The application of pulsed carbon-dioxide lasers for skin resurfacing has been described by several authors. The procedure uses 30 microseconds to 1 ms laser pulses with pulse energies from 100 - 600 mJ to ablate skin for the purpose of smoothing skin irregularities: that is, wrinkle removal. The carbon-dioxide laser has been selected because it ablates a limited layer of tissue (approximately 10 micrometer at a radiant exposure of 5 J/cm 2)4 and produce minimal thermal damage. The purpose of this study is to measure the surface temperature created during a resurfacing procedure and discuss the thermal implications of the measurements. ©2005 Copyright SPIE - The International Society for Optical Engineering.

Optical low-coherence reflectometry and confocal microscopy images were taken of the rat dorsal skin flap window model. Blood vessel depths and diameters measured with the two techniques, and preparation thickness determined from reflectometry images, are in reasonable agreement with measurements from histologic sections. Blood vessels appear as areas of low signal when constant-depth reflectometry images are taken at a depth near the center of a vessel, whereas they appear bright when taken close to the blood-dermis boundary. Doppler shift plus increased light absorption in blood, and the blood-dermis index of refraction mismatch, are discussed as possible causes of the dark- and bright-appearing vessels, respectively. One reflectometry image was used to generate an input grid for a novel Monte Carlo analysis program that is capable of determining the light distribution and heat generation [J/m3] within complex blood vessel geometries. The feasibility of imaging skin blood vessel accurately with optical low-coherence tomography, and using the acquired knowledge of blood vessels structure to create more realistic Monte Carlo analyses is demonstrated by the results of the study. © 1997 Society of Photo-Optical Instrumentation Engineers.

Information regarding energy deposition during laser irradiation of structurally complex biological tissue is needed to understand and improve the results of clinical procedures. A modular adaptive geometry numerical model capable of simulating the propagation of laser light in a wide variety of multiple component tissues has been developed and tested. A material grid array is generated by assigning a value representing a tissue type to each of a large number of small voxels. The grid array is used to indicate optical properties in an existing variable step size, weighted-photon Monte Carlo algorithm that has been modified to account for voxels-to-voxels changes in optical properties. To test the model, simple geometric shapes and optical low coherence reflectometry images of rat skin have been used to create material grids consisting of epidermis, dermis, and blood. The model assumes 1-J/cm2 irradiation of the tissue samples with a 1.0-mm diameter uniform beam at 585 nm. Computed results show good quantitative and qualitative agreement with published data. Various effects due to shading and scattering, similar to those suggested in the literature, are noted. This model provides a way to achieve more realistic representation of anatomical geometry as compared to other models, and produces accurate results.

Individual behavioral plasticity enables animals to adjust to different scenarios. Yet, personality traits limit this flexibility, leading to consistent interindividual differences in behavior. These individual behavioral traits have the potential to govern community interactions, although testing this is difficult in complex natural systems. For large predators who often exert strong effects on ecosystem functioning, this behavioral diversity may be especially important and lead to individualized ecosystem roles. We present a framework for quantifying individual behavioral plasticity and personality traits of large wild predators, revealing the extent to which certain natural behaviors are governed by these latent traits. The outcomes will reveal how the innate characteristics of wildlife can scale up to affect community interactions., Competing Interests: Declaration of interests No interests are declared., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Cacao production is mostly concentrated in Africa, with this continent exporting an impressive 68.4 % of the world's cacao. The increasing demand for cacao from the Global North has already led to massive deforestation in Ghana and Ivory Coast and cacao-driven deforestation is likely to continue changing landscapes in Sub-Saharan Africa. Bats are affected by these landscape changes due to their dependence on multiple resources spread at a large spatial scale. Although bats can save cacao farmers millions of euros through pest suppression, no study has investigated how landscape context affects bat communities in African cacao plantations. Here for the first time, we studied how abundance and richness of insectivorous, frugivorous and nectarivorous bats within cacao landscapes could be affected by cover type and the distance between these habitats and each cacao plantation. We sampled bats using mist-nets in 38 cacao plantations spread throughout southern Cameroon from 2017 to 2020. We found that guilds responded differently to the distance and amount of cover of each of the land cover types, with the scale of response being habitat-dependent. Overall, insectivorous bats were associated positively with high cover of natural habitats (e.g., tree cover, rangeland, and flooded vegetation), and negatively with nearby anthropogenic disturbance (e.g., logging and intensive agriculture). Frugivorous and nectarivorous bats were associated to the presence of natural habitats with water and of nearby anthropogenic habitats (e.g., human settlements, community forests and unpaved roads), probably due to the presence of more fruiting and flowering trees. Considering the associations found between the landscape metrics and bats, we propose three different conceptual designs to manage cacao landscapes: one for insectivores, one for frugivores/nectarivores and a third design that maximises the trade-offs between these three guilds. By safeguarding the diversity of these three guilds farmers can maintain pest suppression services within their plantations and guarantee healthy and long-lasting sustainable cacao landscapes through bats' pollination and seed dispersal., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Anthropogenic factors have impacted the diversity and evolutionary trajectory of various species. This can be through factors such as pressure on population size or range, habitat fragmentation, or extensive manipulation and translocation. Here we use time-calibrated data to better understand the pattern and processes of evolution in the heavily manipulated European fallow deer (Dama dama). During the Pleistocene, fallow deer had a broad distribution across Europe and were found as far north as Britain during the Eemian interglacial. The last glacial period saw fallow deer retreat to southern refugia and they did not disperse north afterwards. Their recolonisation was mediated by people and, from northern Europe and the British Isles, fallow deer were transported around the world. We use ancient and modern mitochondrial DNA (mtDNA) and mitogenomic data from Eemian Britain to assess the pattern of change in distribution and lineage structure across Europe over time. We find founder effects and mixed lineages in the northern populations, and stability over time for populations in southern Europe. The Eemian sample was most similar to a lineage currently in Italy, suggesting an early establishment of the relevant refuge. We consider the implications for the integration of anthropogenic and natural processes towards a better understanding of the evolution of fallow deer in Europe., (© 2024. The Author(s).)

Hierarchical organization of integral membrane proteins (IMP) and lipids at the membrane is essential for regulating myriad downstream signaling. A quantitative understanding of these processes requires both detections of oligomeric organization of IMPs and lipids directly from intact membranes and determination of key membrane components and properties that regulate them. Addressing this, we have developed a platform that enables native mass spectrometry (nMS) analysis of IMP-lipid complexes directly from intact and customizable lipid membranes. Both the lipid composition and membrane properties (such as curvature, tension, and fluidity) of these bilayers can be precisely customized to a target membrane. Subsequent direct nMS analysis of these intact proteolipid vesicles can yield the oligomeric states of the embedded IMPs, identify bound lipids, and determine the membrane properties that can regulate the observed IMP-lipid organization. Applying this method, we show how lipid binding regulates neurotransmitter release and how membrane composition regulates the functional oligomeric state of a transporter., (© 2023. The Author(s), under exclusive licence to Springer Nature America, Inc.)

A number of (hetero)boranes are known in which a main group atom X 'bridges' a B-B connectivity in the open face, and in such species X has previously been described as simply a bridge or, alternatively, as a vertex in a larger cluster. In this study we describe an approach to distinguish between these options based on identifying the best fit of the experimental {B x } cluster fragment with alternate exemplar {B x } fragments derived from DFT-optimized [B n H n ] 2- models. In most of the examples studied atom X is found to be better regarded as a vertex, having 'a 'verticity' of ca. 60-65%. Consideration of our results leads to the suggestion that the radial electron contribution from X to the overall skeletal electron count is more significant than the tangential contribution.

Abundance estimation methods that combine several types of data are becoming increasingly common because they yield more accurate and precise parameter estimates and predictions than are possible from a single data source. These beneficial effects result from increasing sample size (through data pooling) and complementarity between different data types. Here, we test whether integrating mark-recapture data with passive acoustic detections into a joint likelihood improves estimates of population size in a multi-guild community. We compared the integrated model to a mark-recapture-only model using simulated data first and then using a data set of mist-net captures and acoustic recordings from an Afrotropical agroforest bird community. The integrated model with simulated data improved accuracy and precision of estimated population size and detection parameters. When applied to field data, the integrated model was able to produce, for each bird guild, ecologically plausible estimates of population size and detection parameters, with more precision compared with the mark-recapture model. Overall, our results show that adding acoustic data to mark-recapture analyses improves estimates of population size. With the increasing availability of acoustic recording devices, this data collection technique could readily be added to routine field protocols, leading to a cost-efficient improvement of traditional mark-recapture population estimation., (© 2022 The Authors. Ecology published by Wiley Periodicals LLC on behalf of The Ecological Society of America.)

We report herein the first example of the controlled isomerisation of a C , C '-bound (to metal) bis( ortho -carborane) ligand to C , B '-bound with no other change in the molecule. Since the C and B vertices of carboranes have different electron-donating properties this transformation allows the reactivity of the metal centre to be fine-tuned.

The diversification of modern birds has been shaped by a number of radiations. Rapid diversification events make reconstructing the evolutionary relationships among taxa challenging due to the convoluted effects of incomplete lineage sorting (ILS) and introgression. Phylogenomic data sets have the potential to detect patterns of phylogenetic incongruence, and to address their causes. However, the footprints of ILS and introgression on sequence data can vary between different phylogenomic markers at different phylogenetic scales depending on factors such as their evolutionary rates or their selection pressures. We show that combining phylogenomic markers that evolve at different rates, such as paired-end double-digest restriction site-associated DNA (PE-ddRAD) and ultraconserved elements (UCEs), allows a comprehensive exploration of the causes of phylogenetic discordance associated with short internodes at different timescales. We used thousands of UCE and PE-ddRAD markers to produce the first well-resolved phylogeny of shearwaters, a group of medium-sized pelagic seabirds that are among the most phylogenetically controversial and endangered bird groups. We found that phylogenomic conflict was mainly derived from high levels of ILS due to rapid speciation events. We also documented a case of introgression, despite the high philopatry of shearwaters to their breeding sites, which typically limits gene flow. We integrated state-of-the-art concatenated and coalescent-based approaches to expand on previous comparisons of UCE and RAD-Seq data sets for phylogenetics, divergence time estimation, and inference of introgression, and we propose a strategy to optimize RAD-Seq data for phylogenetic analyses. Our results highlight the usefulness of combining phylogenomic markers evolving at different rates to understand the causes of phylogenetic discordance at different timescales. [Aves; incomplete lineage sorting; introgression; PE-ddRAD-Seq; phylogenomics; radiations; shearwaters; UCEs.]., (© The Author(s) 2021. Published by Oxford University Press, on behalf of the Society of Systematic Biologists.)

Aims and Objectives: To critically appraise relevant literature on the lived experiences of registered nurses caring for adults with intellectual disability in the acute care setting in Australia to determine current knowledge and gaps in the literature., Background: People with intellectual disability have the right to the highest attainable health care the same as everyone else. However, inequities still exist in the delivery of health care across the globe, including Australia that result in poorer health outcomes for this population group. Part of the problem is a lack of understanding of the complexities of ID care due to an absence of ID specific content in undergraduate curricula., Design: Integrative literature review., Methods: Electronic databases were searched for relevant empirical and theoretical literature. Additional articles were found by reviewing reference lists of selected articles resulting in ten articles for review. Selected articles were critically appraised using JBI critical appraisal tools. Data were analysed using comparative thematic analysis. PRISMA checklist completed the review., Results: Two main themes emerged from the data that informed the gap in knowledge: (a) Defining nursing practice; and (b) Confidence to practice., Conclusions: There was limited qualitative research published on the topic. International studies revealed that a lack of understanding of the ID condition due to inadequate education left registered nurses feeling underprepared, unsupported and struggling to provide optimal care. No studies were located on the phenomenon within the Australian context. A study exploring the lived experiences of RNs in Australia is needed to offer a deeper understanding of the phenomenon that will help inform practice., Relevance to Practice: Including ID care in national undergraduate and postgraduate nursing curricula must become a nursing educational and professional priority to support nurses more fully in their practice to ensure patients with ID receive the highest attainable standard of nursing care., (© 2021 John Wiley & Sons Ltd.)

Rapidly increasing urbanisation requires mitigation against associated losses of biodiversity and species abundance. In urban-breeding birds, altered food availability for nestlings is thought to reduce reproductive success compared to forest populations. To compensate for shortages of preferred foods, urban parents could increase their search effort for optimal diets or provision other foods. Here, we used telemetry and faecal metabarcoding on blue tits from one urban and one forest populations to compare parental effort and comprehensively describe nestling diet. Urban parents travelled on average 30% further than those in the forest, likely to offset limited availability of high-quality nestling food (i.e. caterpillars) in cities. Metabarcoding, based on a mean number of 30 identified taxa per faeces, revealed that the diets of urban chicks were nonetheless substantially shifted to include alternative foods. While in the forest caterpillars comprised 82 ± 11% of taxa provisioned to nestlings, in the city they constituted just 44 ± 10%. Pre-fledging chick mass as well as offspring numbers were lower in urban than in forest-reared broods. Thus, at least in our comparison of two sites, the hard labour of urban parents did not fully pay off, suggesting that improved habitat management is required to support urban-breeding birds.

We report the light-induced modification of catalytic selectivity for photoelectrochemical CO 2 reduction in aqueous media using copper (Cu) nanoparticles dispersed onto p-type nickel oxide (p-NiO) photocathodes. Optical excitation of Cu nanoparticles generates hot electrons available for driving CO 2 reduction on the Cu surface, while charge separation is accomplished by hot-hole injection from the Cu nanoparticles into the underlying p-NiO support. Photoelectrochemical studies demonstrate that optical excitation of plasmonic Cu/p-NiO photocathodes imparts increased selectivity for CO 2 reduction over hydrogen evolution in aqueous electrolytes. Specifically, we observed that plasmon-driven CO 2 reduction increased the production of carbon monoxide and formate, while simultaneously reducing the evolution of hydrogen. Our results demonstrate an optical route toward steering the selectivity of artificial photosynthetic systems with plasmon-driven photocathodes for photoelectrochemical CO 2 reduction in aqueous media.

Deprotonation of [7-(1'- closo -1',2'-C 2 B 10 H 11 )- nido -7,8-C 2 B 9 H 11 ] - and reaction with [Rh(PPh 3 ) 3 Cl] results in isomerization of the metalated cage and the formation of [8-(1'- closo -1',2'-C 2 B 10 H 11 )-2-H-2,2-(PPh 3 ) 2 - closo -2,1,8-RhC 2 B 9 H 10 ] ( 1 ). Similarly, deprotonation/metalation of [8'-(7- nido -7,8-C 2 B 9 H 11 )-2'-( p -cymene)- closo -2',1',8'-RuC 2 B 9 H 10 ] - and [8'-(7- nido -7,8-C 2 B 9 H 11 )-2'-Cp*- closo -2',1',8'-CoC 2 B 9 H 10 ] - affords [8-{8'-2'-( p -cymene)- closo -2',1',8'-RuC 2 B 9 H 10 }-2-H-2,2-(PPh 3 ) 2 - closo -2,1,8-RhC 2 B 9 H 10 ] ( 2 ) and [8-(8'-2'-Cp*- closo -2',1',8'-CoC 2 B 9 H 10 )-2-H-2,2-(PPh 3 ) 2 - closo -2,1,8-RhC 2 B 9 H 10 ] ( 3 ), respectively, as diastereoisomeric mixtures. The performances of compounds 1 - 3 as catalysts in the isomerization of 1-hexene and in the hydrosilylation of acetophenone are compared with those of the known single-cage species [3-H-3,3-(PPh 3 ) 2 - closo -3,1,2-RhC 2 B 9 H 11 ] ( I ) and [2-H-2,2-(PPh 3 ) 2 - closo -2,1,12-RhC 2 B 9 H 11 ] ( V ), the last two compounds also being the subjects of 103 Rh NMR spectroscopic studies, the first such investigations of rhodacarboranes. In alkene isomerization all the 2,1,8- or 2,1,12-RhC 2 B 9 species ( 1 - 3 , V ) outperform the 3,1,2-RhC 2 B 9 compound I , while for hydrosilylation the single-cage compounds I and V are better catalysts than the double-cage species 1 - 3 .

Heterobimetallic derivatives of a bis(carborane), [μ 7,8 -(1',3'-3'-Cl-3'-PPh 3 - closo -3',1',2'-RhC 2 B 9 H 10 )-2-( p -cymene)- closo -2,1,8-RuC 2 B 9 H 10 ] ( 1 ) and [μ 7,8 -(1',3'-3'-Cl-3'-PPh 3 - closo -3',1',2'-RhC 2 B 9 H 10 )-2-Cp- closo -2,1,8-CoC 2 B 9 H 10 ] ( 2 ) have been synthesised and characterised, including crystallographic studies. A minor co-product during the synthesis of compound 2 is the new species [8-{8'-2'-H-2',2'-(PPh 3 ) 2 - closo -2',1',8'-RhC 2 B 9 H 10 }-2-Cp- closo -2,1,8-CoC 2 B 9 H 10 ] ( 3 ), isolated as a mixture of diastereoisomers. Although, in principle, compounds 1 and 2 could also exist as two diastereoisomers, only one (the same in both cases) is formed. It is suggested that the preferred exopolyhedral ligand orientation in the rhodacarboranes in the non-observed diastereoisomers would lead to unacceptable steric crowding between the PPh 3 ligand and either the p -cymene (compound 1 ) or Cp (compound 2 ) ligand of the ruthenacarborane or cobaltacarborane, respectively., Competing Interests: The authors declare no conflict of interest.

The reaction of 1,1'-Li 2 [(2,2'-C 2 B 10 H 10 ) 2 ] with the cyclometallated gold(III) complex (C^N)AuCl 2 afforded the first examples of gold(III) dicarboranyl complexes. The reactivity of these complexes is subject to the trans-influence exerted by the dicarboranyl ligand, which is substantially weaker than that of non-carboranyl anionic C-ligands. In line with this, displacement of coordinated pyridine by chloride is only possible under forcing conditions. While treatment of (C^N)Au{(2,2'-C 2 B 10 H 10 ) 2 } (2) with triflic acid leads to Au-C rather than Au-N bond protonolysis, aqueous HBr cleaves the Au-N bond to give the pyridinium bromo complex 7. The trans-influence of a series of ligands including dicarboranyl and bis(dicarboranyl) was assessed by means of DFT calculations. The analysis demonstrated that it was not sufficient to rely exclusively on geometric descriptors (calculated or experimental) when attempting to rank ligands for their trans influence. Complex (C^N)Au(C 2 B 10 H 11 ) 2 containing two non-chelating dicarboranyl ligands was prepared similar to 2. Its reaction with trifluoroacetic acid also leads to Au-N cleavage to give trans-(Hpy^C)Au(OAc F )(C 2 B 10 H 11 ) 2 (8). In crystals of 8 the pyridinium N-H bond points towards the metal centre, while in 7 it is bent away. The possible contribution of gold(III)⋅⋅⋅H-N hydrogen bonding in these complexes was investigated by DFT calculations. The results show that, unlike the situation for platinum(II), there is no evidence for an energetically significant contribution by hydrogen bonding in the case of gold(III)., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Space power systems require photovoltaics that are lightweight, efficient, reliable, and capable of operating for years or decades in space environment. Current solar panels use planar multijunction, III-V based solar cells with very high efficiency, but their specific power (power to weight ratio) is limited by the added mass of radiation shielding (e.g., coverglass) required to protect the cells from the high-energy particle radiation that occurs in space. Here, we demonstrate that III-V nanowire-array solar cells have dramatically superior radiation performance relative to planar solar cell designs and show this for multiple cell geometries and materials, including GaAs and InP. Nanowire cells exhibit damage thresholds ranging from ∼10-40 times higher than planar control solar cells when subjected to irradiation by 100-350 keV protons and 1 MeV electrons. Using Monte Carlo simulations, we show that this improvement is due in part to a reduction in the displacement density within the wires arising from their nanoscale dimensions. Radiation tolerance, combined with the efficient optical absorption and the improving performance of nanowire photovoltaics, indicates that nanowire arrays could provide a pathway to realize high-specific-power, substrate-free, III-V space solar cells with substantially reduced shielding requirements. More broadly, the exceptional reduction in radiation damage suggests that nanowire architectures may be useful in improving the radiation tolerance of other electronic and optoelectronic devices.

Three new carboranylphosphines, [1-(1'- closo -1',7'-C 2 B 10 H 11 )-7-PPh 2 - closo -1,7-C 2 B 10 H 10 ], [1-(1'-7'-PPh 2 - closo -1',7'-C 2 B 10 H 10 )-7-PPh 2 - closo -1,7-C 2 B 10 H 10 ], and [1-{PPh-(1'- closo -1',2'-C 2 B 10 H 11 )}- closo -1,2-C 2 B 10 H 11 ], have been prepared, and from a combination of these and literature compounds, eight new carboranylphosphine selenides were subsequently synthesized. The relative basicities of the carboranylphosphines were established by (i) measurement of the 1 J PSe NMR coupling constant of the selenide and (ii) calculation of the proton affinity of the phosphine, in an attempt to establish which of several factors are the most important in controlling the basicity. It is found that the basicity of the carboranylphosphines is significantly influenced by the nature of other substituents on the P atom, the nature of the carborane cage vertex (C or B) to which the P atom is attached, and the charge on the carboranylphosphine. In contrast, the basicity of the carboranylphosphines appears to be relatively insensitive to the nature of other substituents on the carborane cage, the isomeric form of the carborane, and whether the cage is closo or nido (insofar as that does not alter the charge on the cluster). Such information is likely to be of significant importance in optimizing future applications of carboranylphosphines, e.g., as components of frustrated Lewis pairs.