The originality of this work is to highlight the effect of temperature and pressure on the size and morphology of hydrothermal ZnO particles from ambient to supercritical conditions (T > 374 °C and P ...> 221 bar) using a unique continuous one-step process. Experiments were carried out from zinc nitrate (Zn(NO3)2) and potassium hydroxide (KOH) solutions in the ranges of 1–300 bar and 30–400 °C. The as-prepared particles of ZnO (flower, ellipsoid, and sphere) and ε-Zn(OH)2 (polyhedral) sized from nano to micrometers were characterized by X-ray diffraction and electronic microscopy. The wulfingite phase (ε-Zn(OH)2) was detected inside some powders especially at room temperature for higher pressures. The proportion of each phase was determined by the quantitative Rietveld analysis. On the basis of Loüer’s method, ZnO crystals exhibiting a hexagonal structure were considered as cylinders with a diameter D and a height H. The D/H parameter, also known as the aspect ratio, was correlated with electronic microscopy observations to investigate the ZnO nanoparticle morphology evolution according to the temperature and pressure. Thus, a schematic synoptic summarizing these results is presented.
According to the Construction-Integration model (Kintsch
1988
; Kintsch
1998
), two forms of representation are activated during the reading and the comprehension of a text: 1) the text base, which ...includes semantic propositions and 2) the situation model, corresponding to the integration of the information contained in the text to the memories and knowledge of the reader. Functional neuroimaging studies in healthy subjects have shown that the text base is underpinned by frontal regions and lateral temporal regions whereas the situation model would rather depend on the posterior cingulate cortex, the precuneus and other regions depending on the dimension studied. However, the brain regions highlighted so far were only involved in comprehension and not necessary for this cognitive ability. For the first time, we explored the brain structures necessary to understand texts using a combined VBM/DTI approach in neuropsychological patients with whom we obtained comprehension scores (text base and situation model) after the reading of narrative texts. To our great surprise and contrary to our hypotheses, which were based on the results of functional neuroimaging studies, our own results show that it is the hippocampal region that is necessary to activate and memorize/remember the text base and the situation model. The highlighting of a link between the integrity of a portion of the uncinate fasciculus which is well known to play a role in semantic processing and the performance scores of the text base suggests that the hippocampal region is necessary not only for the retrieval of the text base and of the situation model thanks to episodic memory, but also for the activation of the text base during the reading and the comprehension of a text.
The thermal performance curve is an ecological concept relating the phenotype of organisms and temperature. It requires characterization of the leaf temperature for foliar fungal pathogens. ...Epidemiologists, however, use air temperature to assess the impacts of temperature on such pathogens. Leaf temperature can differ greatly from air temperature, either in controlled or field conditions. This leads to a misunderstanding of such impacts.
Experiments were carried out in controlled conditions on adult wheat plants to characterize the response of Mycosphaerella graminicola to a wide range of leaf temperatures. Three fungal isolates were used. Lesion development was assessed twice a week, whereas the temperature of each leaf was monitored continuously.
Leaf temperature had an impact on disease dynamics. The latent period of M. graminicola was related to leaf temperature by a quadratic relationship. The establishment of thermal performance curves demonstrated differences among isolates as well as among leaf layers.
For the first time, the thermal performance curve of a foliar fungal pathogen has been established using leaf temperature. The experimental setup we propose is applicable, and efficient, for other foliar fungal pathogens. Results have shown the necessity of such an approach, when studying the acclimatization of foliar fungal pathogens.
We propose a mesh-free and discrete (particle-based) multi-physics approach for modelling the hydrodynamics in flexible biological valves. In the first part of this study, the method is successfully ...validated against both traditional modelling techniques and experimental data. In the second part, it is further developed to account for the formation of solid aggregates in the flow and at the membrane surface. Simulations of various types of aggregates highlight the main benefits of discrete multi-physics and indicate the potential of this approach for coupling the hydrodynamics with phenomena such as clotting and calcification in biological valves.
Although communication and social difficulties in autism have received a great deal of research attention, the other key diagnostic feature, extreme repetitive behaviour and unusual narrow interests, ...has been addressed less often. Also known as ‘resistance to change’ this may be related to atypical processing of infrequent, novel stimuli. This can be tested at sensory and neural levels. Our aims were to (i) examine auditory novelty detection and its neural basis in children with autism spectrum conditions (ASC) and (ii) test for brain activation patterns that correlate quantitatively with number of autistic traits as a test of the dimensional nature of ASC. The present study employed event-related fMRI during a novel auditory detection paradigm. Participants were twelve 10- to 15-year-old children with ASC and a group of 12 age-, IQ- and sex-matched typical controls. The ASC group responded faster to novel target stimuli. Group differences in brain activity mainly involved the right prefrontal–premotor and the left inferior parietal regions, which were more activated in the ASC group than in controls. In both groups, activation of prefrontal regions during target detection was positively correlated with Autism Spectrum Quotient scores measuring the number of autistic traits. These findings suggest that target detection in autism is associated not only with superior behavioural performance (shorter reaction time) but also with activation of a more widespread network of brain regions. This pattern also shows quantitative variation with number of autistic traits, in a continuum that extends to the normal population. This finding may shed light on the neurophysiological process underlying narrow interests and what clinically is called ‘need for sameness’.
Imatinib is the standard of care in adults with chronic myeloid leukemia (CML) in chronic phase (CP). Only a few studies to assess efficacy in children have been performed. We report on the results ...of the French prospective trial (ClinicalTrials.gov identifier NCT00845221) conducted in children and adolescents with newly diagnosed CML in CP.
A total of 44 patients from age 10 months to 17 years with newly diagnosed CML in CP received daily imatinib 260 mg/m(2). Progression-free survival, responses, and tolerance were evaluated.
With a median follow-up times of 31 months (range, 11 to 64 months), the estimated progression-free survival rate at 36 months was 98% (95% CI, 85% to 100%). A complete hematologic response was achieved in 98% of the patients. The rates of complete cytogenetic response (CCyR) and major molecular response (MMR) were 61% and 31% at 12 months, respectively. During follow-up, CCyR and MMR were achieved in 36 children (77%) and 25 children (57%), respectively. Overall, 30% of the patients discontinued imatinib, mainly because of unsatisfactory response. The most common adverse events were neutropenia and musculoskeletal events.
Imatinib is effective in children with CML in CP with response rates similar to rates reported in adults. The adverse effects are acceptable, but longer follow-up studies are required to fully assess the long-term impact.
This work concerns the sintering of tungsten-based (i.e WMoTaNb) high entropy alloy (HEA) powders using the spark plasma sintering (SPS) technique and their mechanical properties. The synthesis was ...performed by a self-propagating high-temperature synthesis (SHS) type reaction in which the mixture of metallic oxides (WO3, MoO3 …) is reduced by magnesium. For this, a specific reactor has been developed. Different conditions including the addition of a moderator were tested. These powders are then densified by SPS technology which allows for keeping the initial microstructure of the powder. The optimization of sintering conditions was performed with the objective to control simultaneously the chemical composition, the grain growth and the densification stages.
Spark plasma sintering (SPS) has been used to sinter a milled oxide dispersion-strengthened (ODS) FeAl powder in order to prepare dense nanostructured parts. The effect of processing conditions ...including sintering temperature, holding time and degassing treatments on the microstructure and mechanical properties of the as-sintered materials was investigated. A hetero-nanostructure that contains nano, ultrafine and micrometric grains was confirmed to be developed whatever the processing window, due to the large temperature difference generated during the SPS process itself. The grain size distribution can be tailored by selecting a combination of sintering temperature and holding time while retaining a full densification, which shows the elaboration flexibility of this SPS processing. Increase of the global hardness by reducing average grain size down to the sub-micrometer scale is straightforward. However, the ductility although improved after pre and in-situ degassing treatments is determined by the sample imperfections such as low inter-particle bonding and high oxygen content.
Soft magnetic Fe65Ni28Mn7 (at. %) alloy was successfully synthesized by mechanical alloying and spark plasma sintering (SPS) and, in parallel, the same composition was prepared by arc melting (AM) ...for comparison. Several SPS conditions were tested. X-ray diffraction and scanning electron microscopy were used to investigate the structure, phase composition, and morphology of the samples. It was found that mechanical alloying produced BCC and FCC supersaturated solid solution after 130 h of milling, with a fine microstructure (i.e., crystallite size of 10 nm). Spark plasma sintering performed at 750 °C and 1000 °C under two pressures of 50 MPa and 75 MPa revealed stable FCC phases. A single FCC phase was observed after the arc melting synthesis. The magnetic properties of milled powders and solids obtained by AM and SPS were investigated. The specimen consolidated by SPS at 1000 °C under the pressure of 50 MPa exhibits soft magnetic behavior (coercivity 0.07 Oe), whereas the mechanically alloyed sample revealed hard magnetic behavior. The specimen consolidated at 750 °C under a pressure of 75 MPa showed a higher compressive strength of 1700 MPa and a Vickers hardness of 425 ± 18 HV. As a result, sintering at 750 °C/75 MPa can be utilized to enhance the mechanical properties, while those sintered at 1000 °C/50 MPa increase magnetic softness.
This paper reports on the development of a measurement instrument to perform gloss measurements using an image-based detector. The image-based gloss meter was built according to the specifications of ...the optical layout of a specular gloss meter in a 60° measurement geometry, as described in ASTM D523-14. The photodiode detector was thereby substituted with a CMOS detector. The optical layout of the system was designed and validated by the use of ray tracing software. A series of 16 matte to high-gloss test samples, with nominal gloss values ranging between 3 and 90 gloss units, was used to compare specular gloss measurements obtained with the developed instrument and a commercial specular gloss meter. An average and maximum deviation of only 1.2 and 2.7 gloss units, respectively, was obtained, confirming the suitability of the system to perform standard specular gloss measurements. The potential benefits of the image-based approach were then studied. By way of example, the optical characterization of orange peel and contrast gloss by the use of the system was discussed, corroborating the fact that the proposed instrument offers important opportunities for a more global characterization of the total gloss impression.
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