•Recrystallization texture in high entropy alloys is reported for the first time.•The texture is compared to other low SFE alloys e.g. TWIP and austenitic steels.•Great resistance to grain coarsening ...during recrystallization.•Retention of deformation texture components during annealing like TWIP steels.•Stronger S than Brass and Goss components unlike TWIP and austenitic steels.
Evolution of microstructure and texture after heavy cold rolling and subsequent annealing in a wide temperature range was first studied in an FCC equiatomic CoCrFeMnNi high-entropy alloy (HEA). Development of a submicron-cell structure and a strong brass-type texture was observed after 90% cold rolling. An ultrafine microstructure having average recrystallized grain size ∼1μm with profuse annealing twins was observed after annealing at 650°C. Remarkable resistance against grain coarsening was observed at least up to 800°C. The mechanisms for these features were closely related with the distinct whole-solute matrix in HEAs. The recrystallization texture was characterized by the retention of deformation texture components similar to those of TWIP and 316 stainless steels. But notable differences exist. The S ({123}〈634〉) component is stronger than brass ({110}〈112〉) and Goss ({110}〈001〉), and strengthened with increasing annealing temperatures. Strong α-fiber (〈110〉//ND) components other than the deformation components BS and G, and higher fraction of random components also develop. It could be attributed to profuse annealing twin formation due to the low stacking fault energy of the alloy.
This paper, developed under the framework of the RECCAP initiative, aims at providing improved estimates of the carbon and GHG (CO2, CH4 and N2O) balance of continental Africa. The various components ...and processes of the African carbon and GHG budget are considered, existing data reviewed, and new data from different methodologies (inventories, ecosystem flux measurements, models, and atmospheric inversions) presented. Uncertainties are quantified and current gaps and weaknesses in knowledge and monitoring systems described in order to guide future requirements. The majority of results agree that Africa is a small sink of carbon on an annual scale, with an average value of −0.61 ± 0.58 Pg C yr−1. Nevertheless, the emissions of CH4 and N2O may turn Africa into a net source of radiative forcing in CO2 equivalent terms. At sub-regional level, there is significant spatial variability in both sources and sinks, due to the diversity of biomes represented and differences in the degree of anthropic impacts. Southern Africa is the main source region; while central Africa, with its evergreen tropical forests, is the main sink. Emissions from land-use change in Africa are significant (around 0.32 ± 0.05 Pg C yr−1), even higher than the fossil fuel emissions: this is a unique feature among all the continents. There could be significant carbon losses from forest land even without deforestation, resulting from the impact of selective logging. Fires play a significant role in the African carbon cycle, with 1.03 ± 0.22 Pg C yr−1 of carbon emissions, and 90% originating in savannas and dry woodlands. A large portion of the wild fire emissions are compensated by CO2 uptake during the growing season, but an uncertain fraction of the emission from wood harvested for domestic use is not. Most of these fluxes have large interannual variability, on the order of ±0.5 Pg C yr−1 in standard deviation, accounting for around 25% of the year-to-year variation in the global carbon budget. Despite the high uncertainty, the estimates provided in this paper show the important role that Africa plays in the global carbon cycle, both in terms of absolute contribution, and as a key source of interannual variability.
Two innovative single-ridge waveguide to rectangular waveguide transitions with integrated 90° E-plane bend are proposed. Since a single-ridge waveguide standard is not available, such components ...become necessary whenever this technology is employed. Wideband performance, extreme compactness and easy manufacturing are core characteristics. The presented devices operate at Ku band, though the designs are fully scalable to any other frequency band of interest.
Saliva contains cells and compounds, of local and non‐local oral origin, namely inorganic, organic non‐protein, protein/polypeptide, and lipid molecules. Moreover, some hormones, commonly assayed in ...plasma, such as steroids, are detectable in oral fluid and peptide/protein, and non‐steroid hormones have been investigated. The sports practice environment and athletes' availability, together with hormone molecule characteristics in saliva and physical exercise behavior effects, confirm this body fluid as an alternative to serum. This review focuses on the relation between salivary steroids and psycho‐physiological stress and underlines how the measurement of salivary cortisol provides an approach of self‐report psychological indicator and anxiety change in relation to exercise performance. The correlation between salivary and plasma steroid hormone (cortisol, testosterone, and dehydroepiandrosterone (DHEA)) levels, observed during exercise, has been considered, underlining how the type, duration, and intensity of the exercise influence the salivary steroid concentrations in the same way as serum‐level variations. Training conditions have been considered in relation to the salivary hormonal response. This review focuses on studies related to salivary hormone measurements, mainly steroids, in physical exercise. Saliva use in physical disciplines, as a real alternative to serum, could be a future perspective.
A novel right-angle coaxial-to-single ridge waveguide transition with capacitive coupling is presented at X band. Contrarily to the state of the art, the coaxial inner conductor is not in DC contact ...with the ridge, and such a feature can be a considerable mechanical advantage in the manufacturing of high-performance systems. In addition to this, few geometrical parameters need to be optimised, thus simplifying the overall design with respect to traditional counterparts. Nevertheless, the whole X band can be potentially covered with a return loss better than 20 dB. An ultra-compact transition is designed, manufactured with stereolithography technology and tested in a back-to-back configuration. Good agreement between simulated and measured results is observed for a proof-of-concept prototype.
► The mirror neuron system sub-serves both motor imagery and action observation. ► Both motor imagery and action observation play a role in motor learning. ► In this study we compared these ...strategies in learning a novel complex motor task. ► Action observation revealed better than motor imagery as a motor learning strategy. ► This is relevant in educational activities, sport training and neurorehabilitation.
Both motor imagery and action observation have been shown to play a role in learning or re-learning complex motor tasks. According to a well accepted view they share a common neurophysiological basis in the mirror neuron system. Neurons within this system discharge when individuals perform a specific action and when they look at another individual performing the same or a motorically related action. In the present paper, after a short review of literature on the role of action observation and motor imagery in motor learning, we report the results of a kinematics study where we directly compared motor imagery and action observation in learning a novel complex motor task. This involved movement of the right hand and foot in the same angular direction (in-phase movement), while at the same time moving the left hand and foot in an opposite angular direction (anti-phase movement), all at a frequency of 1Hz. Motor learning was assessed through kinematics recording of wrists and ankles. The results showed that action observation is better than motor imagery as a strategy for learning a novel complex motor task, at least in the fast early phase of motor learning. We forward that these results may have important implications in educational activities, sport training and neurorehabilitation.
A new and efficient formulation of the Discrete-Continuous Model (DCM) for the simulation of 3D dislocation dynamics in complex finite or periodic volumes is presented. As in previous versions, the ...improved model is based on a coupling between a Dislocation Dynamics (DD) code and a Finite Element (FE) code through eigenstrain theory. Short-range interactions are now handled more properly. Specifically, in the continuous limit the stress field driving the dislocation dynamics is now reconstructed consistently. Furthermore, the DCM can now handle nonstructured meshes, and free surface and interface handling does not depend on having a structured mesh anymore. Also numerical experiments shed some light on the influence of the choice of the FE quadrature. Some approximations are proposed and justified, and the use of advanced algorithmic techniques are used for time integration and the homogeneisation procedure to reach a high computational efficiency. Basic tests demonstrate the validity and the efficiency of the proposed strategy. Remarkably, it is demonstrated that for a periodic domain the DCM with a very fine FE mesh is actually faster than a corresponding classical DD simulation.
•The Discrete-Continuous Model (DCM), which couples a dislocation dynamics and a Finite- Element code, has been reformulated.•The new formulation leads to a proper reconstruction of the stress field driving the dynamics of dislocations•A strategy for handling material interfaces, free surfaces and domains boundaries is presented•Some performance optimiszations are proposed.•Simple validation tests demonstrate the new Discrete-Continuous Model performance.
Background
Pain drawings (PDs) are an important component of the assessment of a patient with pain. The aim of this work is to present the test–retest reliability of a novel method of quantifying the ...extent and location of pain. Additionally, the association between PD variables and clinical features in patients with chronic neck pain (CNP) and chronic low back pain (CLBP) was explored.
Methods
Fifty‐one patients with CLBP and 56 patients with CNP participated. Each patient shaded two consecutive PDs using a digital tablet. Software was developed to quantify the pain extent, to analyse the pain overlap between PDs and to produce pain frequency maps. Correlations were obtained between pain extent and clinical features including the level of pain intensity, disability, and psychological distress and cognitive function.
Results
The intraclass correlation coefficients for pain extent in CLBP and CNP were very high: 0.97 (95% CI: 0.95–0.98) and 0.92 (95% CI: 0.87–0.98), respectively. The Bland Altman showed a mean difference close to zero: 5.4% pixels in CNP group and 3% pixels in the CLBP group. Significant correlations were observed between pain extent and pain intensity in CLBP and CNP and pain extent and disability in CNP. There was no relation between pain extent and the level of distress or cognitive function.
Conclusions
A novel method for the acquisition of PD was presented. Test–retest reliability of reporting pain extent and pain location was supported in people with CNP and CLBP. Future research is needed to establish psychometric properties of PD.
Background and purpose: The transient receptor potential ankyrin receptor 1 (TRPA1) is a cation channel, co‐expressed with the pro‐tussive transient receptor potential vanilloid type 1 (TRPV1) ...channel in primary sensory neurons. TRPA1 is activated by a series of irritant exogenous and endogenous α,β‐unsaturated aldehydes which seem to play a role in airway diseases. We investigated whether TRPA1 agonists provoke cough in guinea pigs and whether TRPA1 antagonists inhibit this response.
Experimental approach: Animals were placed in a Perspex box, and cough sounds were recorded and counted by observers unaware of the treatment used.
Key results: Inhalation of two selective TRPA1 agonists, allyl isothiocyanate and cinnamaldehyde, dose‐dependently caused cough in control guinea pigs, but not in those with airway sensory nerves desensitized by capsaicin. Coughs elicited by TRPA1 agonists were reduced by non‐selective (camphor and gentamicin) and selective (HC‐030031) TRPA1 antagonists, whereas they were unaffected by the TRPV1 antagonist, capsazepine. Acrolein and crotonaldehyde, two α,β‐unsaturated aldehydes recently identified as TRPA1 stimulants and contained in cigarette smoke, air pollution or produced endogenously by oxidative stress, caused a remarkable tussive effect, a response that was selectively inhibited by HC‐030031. Part of the cough response induced by cigarette smoke inhalation was inhibited by HC‐030031, suggesting the involvement of TRPA1.
Conclusions and implications: A novel pro‐tussive pathway involves the TRPA1 channel, expressed by capsaicin‐sensitive airway sensory nerves and is activated by a series of exogenous (cigarette smoke) and endogenous irritants. These results suggest TRPA1 may be a novel target for anti‐tussive medicines.
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