Nanocomposite films composed of gold nanoparticles (AuNPs) embedded in a TiO2 matrix have been prepared by direct liquid injection chemical vapor deposition process, using preformed nanoparticles and ...titanium isopropoxide as precursors. The spherical AuNPs about 4.1 nm in diameter were synthesized by using gold (III) chloride trihydrate and stabilized by thiol ligands. The depositions were carried out by performing at first oxide deposition, then gold nanoparticle one and capping with oxide. The morphology, structure; the chemical state and optical properties of nanocomposite films were characterized by scanning electron microscopy, Raman, X-ray photoelectron and UV–Vis absorption spectroscopies, respectively. The stability of the films upon thermal annealing up to 800 °C was studied.
•Preformed gold nanoparticles and titanium tetraisopropoxide were used as precursors.•Au–TiO2 films were composed of gold nanoparticles embedded in the TiO2 matrix.•The growth of TiO2 films was not modified by the insertion of gold nanoparticles.•The size of the preformed gold nanoparticles was preserved during the deposition.•The annealing treatments did not modify the morphology of the gold nanoparticles.
Robust monitoring programs are essential for understanding changes in wildlife population dynamics and distribution over time, especially for species of conservation concern. In this study, we ...applied a rapid non-invasive sampling approach to the Critically Endangered African forest elephant (Loxodonta cyclotis), at nationwide scale in its principal remaining population strongholds in Gabon. We used a species-specific customized genetic panel and spatial capture-recapture (SCR) approach, which gave a snapshot of current abundance and density distribution of forest elephants across the country. We estimated mean forest elephant density at 0.38 (95% Confidence Interval 0.24–0.52) per km2 from 18 surveyed sites. We confirm that Gabon is the main forest elephant stronghold, both in terms of estimated population size: 95,110 (95% CI 58,872–131,349) and spatial distribution (250,782 km2). Predicted elephant densities were highest in relatively flat areas with a high proportion of suitable habitat not in proximity to the national border. Protected areas and human pressure were not strong predictors of elephant densities in this study. Our nationwide systematic survey of forest elephants of Gabon serves as a proof-of-concept of application of noninvasive genetic sampling for rigorous population monitoring at large spatial scales. To our knowledge, it is the first nationwide DNA-based assessment of a free-ranging large mammal in Africa. Our findings offer a useful national baseline and status update for forest elephants in Gabon. It will inform adaptive management and stewardship of elephants and forests in the most important national forest elephant stronghold in Africa.
•Non-invasive sampling approach utilizing a species-specific customized genetic panel.•Estimate of 95,110 (95% Confidence Interval 58,872-131,349) forest elephants in Gabon.•Gabon confirmed as main stronghold for critically endangered African forest elephants.•First nationwide DNA-based assessment of a free-ranging large mammal in Africa.
Laser ablation of metallic targets in gas atmospheres gives rise to the formation of nanoparticle (NP) powders when high laser irradiances (i.e., > 1 GW/cm² for aluminium targets) are used. The ...properties of the NPs so formed vary as a function of the laser irradiation parameters and the pressure and composition of the ambient gas. Here, we studied the composition and structure of NPs formed by laser ablation of Al targets with a nanosecond Nd:YAG laser emitting at 1064 nm. The laser irradiance was 2.5 GW/cm
2
. N
2
–O
2
gas mixtures containing different amounts of nitrogen (100–80 vol% N
2
) were used as ambient gas at atmospheric pressure. The influence of the ambient gas composition on the morphology and the structure of the NPs was studied ex-situ by scanning and transmission electron microscopy, X-ray diffraction and micro-Raman spectroscopy. Their composition of light elements was determined by ion beam analysis. It was shown that together with metallic aluminium, different amounts of aluminium nitride and aluminium oxynitride were formed in the NPs as a function of the nitrogen concentration in the ambient gas. Below 95 vol% N
2
, the concentration of nitride phases decreases strongly. However, the formation of aluminium oxide (Al
2
O
3
) was not observed, whereas it was detected in NPs formed in air. A discussion of these results that takes into account the dynamics of the plasma plume is proposed.
KxWO3 nanorods, interesting as gas sensors, were elaborated on mica muscovite substrate and characterized by atomic force microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, ...and mainly transmission electron microscopy. A combination of structural analyses allowed determining the morphology of these rods, and selected area electron diffraction experiments pointed out the simultaneous presence of the exotic hexagonal and stable monoclinic phases. Moreover, the presence of potassium inside the nanorods, coming from the mica substrate, was revealed. By combining all the observations, a growth model is proposed, consisting of the stacking of two different crystallographic structures. An interfacial hexagonal KxWO3 tungsten bronze grows in epitaxy on the mica substrate, followed by the growth of monoclinic trioxide tungsten. The stability of these nanometric objects was studied by annealing up to 870 K, indicating that the transformation of the presumed metastable hexagonal phase never occurred.
The coast of Gabon is one of the most important nesting sites for the endangered leatherback sea turtle
Dermochelys coriacea. In this study, hatchling orientation was recorded during natural ...emergences at Pongara National Park, Gabon. This nesting beach is located close to both the capital of Gabon and a developing resort area, Pointe Denis. Under natural conditions most sea turtle hatchlings emerge at night and orient to the ocean by crawling away from dark, high silhouettes landward towards the bright, low seaward horizons. Artificial lights interfere with natural cues and disrupt hatchling orientation. The relative influence of artificial lights, logs and erosion were assessed on the nesting beach in Pongara National Park using a linear mixed model. We found that the attraction to artificial lights was higher than the effect of silhouette cues landward alone, but could be balanced by the simultaneous presence of the moon. Based upon these results, we recommend combining light management in the resort area to reduce the light pollution on the nesting beach and reinforcement of natural cues landward to minimize the effect of the remaining light pollution from the capital.
The increasing incidence of aging adults with cognitive-communication impairments and demand for services that enhance the quality of life of this population necessitates examination of the ...evidence-based strategies that hold the most promise in producing desired quality-of-life outcomes. The adoption of person-centered care approaches in health care () allows for a better understanding of how to include the person with cognitive-communication impairment in the process of identifying communication needs, developing intervention approaches, and modifying strategies as needs change. The continuum of dementia severity and the cognitive-communication characteristics at each stage are outlined as a guide for selecting compensatory communication supports to fit changing needs. Environmental features and the training of caregivers are important components of a person-centered care model that aims to ensure that individuals with dementia are respected and can live fulfilling lives.
•NPs formed in a plasma-plume during laser irradiation of metals (Al, Ti, Ag) were studied.•In situ SAXS and ex situ TEM, XRD and Raman spectra were measured.•NPs size decreased when increasing the ...O2 fraction in a controlled O2+N2 atmosphere.•The oxidation of metal NPs in the plasma restricts the increase of the size of the NPs.
The influence of a reactive atmosphere on the formation of nanoparticles (NPs) in the plasma plume generated by nanosecond pulsed laser irradiation of metal targets (Ti, Al, Ag) was probed in situ using Small Angle X-ray Scattering (SAXS). Air and different O2–N2 gas mixtures were used as reactive gas within atmospheric pressure. SAXS results showed the formation of NPs in the plasma-plume with a mean radius varying in the 2–5nm range. A decrease of the NPs size with increasing the O2 percentage in the O2–N2 gas mixture was also showed. Ex situ observations by transmission electron microscopy and structural characterizations by X-ray diffraction and Raman spectroscopy were also performed for powders collected in experiments done using air as ambient gas. The stability of the different metal oxides is discussed as being a key parameter influencing the formation of NPs in the plasma-plume.
We examined the effects of communication skills training and the use of memory books by certified nursing assistants (CNAs) on verbal interactions between CNAs (n = 64) and nursing home residents (n ...= 67) during care routines.
CNAs were taught to use communication skills and memory books during their interactions with residents with moderate cognitive impairments and intact communication abilities. A staff motivational system was used to encourage performance and maintenance of these skills. Formal measures of treatment implementation were included.
Results were compared with those for participants on no-treatment control units. Trained CNAs talked more, used positive statements more frequently, and tended to increase the number of specific instructions given to residents. Changes in staff behavior did not result in an increase in total time giving care to residents. Maintenance of CNA behavior change was found 2 months after research staff exited the facility. Although an increase was found in positive verbal interactions between CNAs and residents on intervention units, other changes in resident communication were absent.
Nursing staff can be trained to improve and maintain communication skills during care without increasing the amount of time delivering care. The methodological advantages of including measures to assess treatment implementation are discussed.
Speech–language pathologists (SLPs) have an important role in supporting the caregivers of persons with dementia from diagnosis through the end of life in 4 major areaseducation, training to use ...effective cognitive communication strategies identified for clients with dementia, psychosocial/emotional support, and counseling. Speech–language pathologists may be involved in this process from the initial diagnosis when families need guidance to navigate the vast amounts of information on the Internet and elsewhere, until they need assistance in making end-of-life decisions. Speech–language pathologists must recognize that caregivers have needs, and differing needs, depending on the stage of dementia of the person to whom they are providing care. The research in caregiving interventions for family, professional, and paraprofessional caregivers provides an understanding of effective, evidence-based approaches, resources, and promising caregiver outcomes for the SLP working with individuals with dementia and their caregivers. It is important for SLPs to know that these interventions exist and to seek out appropriate services to which to refer the caregivers of their clients. Other person-centered interventions specifically developed for SLPs to implement with their clients with dementia and their family and professional caregivers are crucial for ensuring a quality life for clients and caregivers and for meeting the demands of a quality dementia care workforce.
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