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Recent experimental results showed that an electron gas in an asymmetrical double barrier heterostructure can be effectively cooled down under resonant tunneling condition, thus leading to the realization of an electronic cooler. The cooling process is a multi-parameters phenomenon and it is desirable to handle this problem through a reasonably simple approach, in order to understand the role of each parameter. To this end, we present a rate equation modeling of the electron cooling. We model the resonant tunnel injection of the electrons in the well and their thermionic emission assisted by Longitudinal Optical (LO) phonons absorption and emission. The influence of several parameters on the electronic temperature is discussed. This simple model compares rather well to the predictions of non-equilibrium Green function approach and to the experiments. [ABSTRACT FROM AUTHOR]

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Hypertensive postmenopausal women are more likely to develop adverse cardiac remodeling and respond less effectively to drug treatment than men. High-intensity interval exercise (HIIE) is a nonpharmacological strategy for the treatment of hypertension; however, the effectiveness in women remains uncertain. This study was designed to evaluate 1) the effects of HIIE training upon morphological and functional markers of cardiovascular health in female SHR and 2) to determine whether the hormonal shift induced by ovariectomy could influence cardiovascular responses to HIIE. Thirty-six SHR were randomly assigned to four groups: ovariectomized sedentary, ovariectomized trained, sham-operated sedentary, and sham-operated trained. The trained rats performed HIIE 5 days/wk for 8 wk. Blood pressure and echocardiographic measurements were performed before and after training in animals. Cardiac response to β-adrenergic stimulation and the expression of calcium regulatory proteins and estrogen receptors in heart samples were assessed. Endothelium-dependent vasorelaxation in response to acetylcholine was evaluated in aortic rings as well as the expression of nitric oxide synthase isoforms (eNOS and P-eNOS) by Western blotting. In both groups of trained SHR, HIIE induced eccentric cardiac remodeling with greater inotropic and chronotropic effects, as well as an increase in SERCA and β1AR expression. However, although the trained rats showed improved endothelial function and expression of eNOS and P-eNOS in the aorta, there was no demonstrated effect on blood pressure. In addition, the responses to HIIE training were not affected by ovariectomy. This work highlights the importance of assessing the cardiovascular efficacy and safety of different exercise modalities in women. NEW & NOTEWORTHY: This study reports the effects of high-intensity interval exercise (HIIE) training on cardiac and endothelial function in female hypertensive rats. Despite a lack of effect on blood pressure (BP), HIIE training induces eccentric cardiac remodeling with greater functionals effects. Furthermore, training has beneficial effects on endothelial function. However, ovarian hormones do not seem to modulate cardiac and aortic adaptations to this training modality. All this underlines the need to consider training modalities on the cardiovascular system in women. [ABSTRACT FROM AUTHOR]

Self-synchronization is a ubiquitous phenomenon in nature, in which oscillators are collectively locked in frequency and phase through mutual interactions. While self-synchronization requires the forced excitation of at least one of the oscillators, we demonstrate that this mechanism spontaneously appears due to activation from thermal fluctuations. By performing molecular dynamics simulations, we demonstrate self-synchronization in a platform supporting doped silicon resonator nanopillars having different eigenfrequencies. We find that pillar's vibrations are spontaneously converging to the same frequency and phase. In addition, the dependencies on the intrinsic frequency difference and the coupling strength agree well with the Kuramoto model predictions. More interestingly, we find that a balance between energy dissipation resulting from phonon–phonon scattering and potential energy between oscillators is reached to maintain synchronization. The balance could be suppressed by increasing the membrane size. While microscopic stochastic motions are known to follow random probability distributions, we finally prove that they can also yield coherent collective motions via self-synchronization. [ABSTRACT FROM AUTHOR]

In this work, a methodology is presented for city-wide road traffic noise indicator mapping. The need for direct access to traffic data is bypassed by relying on street categorization and a city microphone network. The starting point for the deterministic modeling is a previously developed but simplified dynamic traffic model, the latter necessary to predict statistical and dynamic noise indicators and to estimate the number of noise events. The sound propagation module combines aspects of the CNOSSOS and QSIDE models. In the next step, a machine learning technique—an artificial neural network in this work—is used to weigh the outcomes of the deterministic predictions of various traffic parameter scenarios (linked to street categories) to approach the measured indicators from the microphone network. Application to the city of Barcelona showed that the differences between predictions and measurements typically lie within 2–3 dB, which should be positioned relative to the 3 dB variation in street-side measurements when microphone positioning relative to the façade is not fixed. The number of events is predicted with 30% accuracy. Indicators can be predicted as averages over day, evening and night periods, but also at an hourly scale; shorter time periods do not seem to negatively affect modeling accuracy. The current methodology opens the way to include a broad set of noise indicators in city-wide environmental noise impact assessment. [ABSTRACT FROM AUTHOR]

Electron-phonon coupling limited transport in phosphorene metal oxide semiconductor field effect transistors (MOSFETs) is studied along the armchair (AC) and zigzag (ZZ) directions. In a multiscale approach, the unit cell of phosphorene is first relaxed, and the band structure is calculated using hybrid density functional theory (DFT). The transport equations are then solved quantum mechanically under the nonequilibrium Green's function formalism using DFT-calibrated two-band k ⋅ p hamiltonian. The treatment of electron-phonon scattering is done under the self-consistent Born approximation in conjunction with deformation potential theory. It is found that optical phonon modes are largely responsible for degradation of ON-current apart from p-channel AC MOSFET where acoustic phonon modes play a stronger role. It is further observed that electron-phonon scattering is more pronounced in the ZZ direction, whereas the diffusive ON-current of p-MOSFET in a given direction is higher than n-MOSFET. Further study on the complex band structure of phosphorene reveals band wrapping within the bandgap region in the AC direction and multiple crossings in the ZZ direction. This signifies strong phonon-assisted tunneling in the ZZ direction in comparison with the AC direction. For completeness, drain current in the AC tunnel field effect transistor is calculated, and electron-phonon scattering is observed only in the near vicinity of the OFF-current. [ABSTRACT FROM AUTHOR]

Background: Caveolae are invaginated plasma membrane domains of 50–100 nm in diameter involved in many important physiological functions in eukaryotic cells. They are composed of different proteins, including the membrane-embedded caveolins and the peripheric cavins. Caveolin-1 has already been expressed in various expression systems (E. coli, insect cells, Toxoplasma gondii, cell-free system), generating intracellular caveolin-enriched vesicles in E. coli, insect cells and T. gondii. These systems helped to understand the protein insertion within the membrane and its oligomerization. There is still need for fundamental insights into the formation of specific domains on membrane, the deformation of a biological membrane driven by caveolin-1, the organization of a caveolar coat, and the requirement of specific lipids and proteins during the process. The aim of this study was to test whether the heterologously expressed caveolin-1β was able to induce the formation of intracellular vesicles within a Gram+ bacterium, Lactococcus lactis, since it displays a specific lipid composition different from E. coli and appears to emerge as a good alternative to E. coli for efficient overexpression of various membrane proteins. Results: Recombinant bacteria transformed with the plasmid pNZ-HTC coding for the canine isoform of caveolin-1β were shown to produce caveolin-1β, in its functional oligomeric form, at a high expression level unexpected for an eukaryotic membrane protein. Electron microscopy revealed several intracellular vesicles from 30 to 60 nm, a size comparable to E. coli h-caveolae, beneath the plasma membrane of the overexpressing bacteria, showing that caveolin-1β is sufficient to induce membrane vesiculation. Immunolabelling studies showed antibodies on such neo-formed intracellular vesicles, but none on plasma membrane. Density gradient fractionation allowed the correlation between detection of oligomers on Western blot and appearance of vesicles measurable by DLS, showing the requirement of caveolin-1β oligomerization for vesicle formation. Conclusions: Lactococcus lactis cells can heterologously overexpress caveolin-1β, generating caveolin-1β enriched intracellular neo-formed vesicles. These vesicles might be useful for potential co-expression of membrane proteins of pharmaceutical interest for their simplified functional characterization. [ABSTRACT FROM AUTHOR]

In the view of a circular economy, there is an increasing need for (re-)using animal by-products that have a wide range of applications and sufficient safety. Hydrolysates of animal proteins (HPs) are frequently used as feed ingredients. Nevertheless, clear criteria for legal use and methods for monitoring feed applications are not available. Here, a range of methods have been used and evaluated for characterizing a set of 26 samples of hydrolysed proteins, 'hydrolysed' feather meals and processed animal proteins (PAPs), with verification based on an additional set of eight samples. Methods included determination of ash content, sediment (mineral fraction) content, protein content, species identity, solubility, protein solubility, size exclusion chromatography and polyacrylamide gel electrophoresis (SDS-PAGE). After a comparison of results obtained with water and SDS, water was chosen as the solvent for environmental and occupational reasons. Typical HP samples have a protein content higher than 60%, a solubility exceeding 50% and a virtual absence of a mineral fraction. The first discrimination between HPs and PAPs could be based on the absence or presence, respectively, of a mineral fraction. An approach for HP characterization is designed using a Hydrolysation Index (HI) based on the fraction of peptides smaller than 10 kDa, the solubility of the sample and the fraction of soluble proteins. A simplified version (HIs), exclusively based on the fraction of peptides smaller than 10 kDa and the solubility of the sample, shows a trend among the samples highly comparable to HI. Values for HI and HIs exceeding 60% would characterise HPs. Feather meals, which are heat treated instead of treatment by a chemical process of hydrolysation, range among the PAPs and should not be indicated as "hydrolysed." The HIs can be used as an easy parameter for classifying HPs and for legal enforcement. [ABSTRACT FROM AUTHOR]

There has been significant work investigating the use of self assembled monolayers (SAMs) made of ferrocenyl terminated alkanethiols for realizing molecular diodes, leading to remarkably large forward-to-reverse current rectification ratios. In this study, we use a multiband barrier tunneling model to examine the electrical properties of SAM-based molecular diodes made of HSC9Fc, HSC11Fc, and HSCiFcC13-i (0 ≤ I ≤ 13). Using our simple physical model, we reproduce the experimental data of charge transport across various ferrocenyl substituted alkanethiols performed by Nijhuis, Reus, and Whitesides [J. Am. Chem. Soc. 132, 18386184016 (2010)] and Yuan et al. [Nat. Commun. 6, 6324 (2015)]. Especially, the model allows predicting the rectification direction in HSCiFcC13-i (0 ≤I ≤13) based molecular diodes depending on the position of the ferrocenyl (Fc) moiety within the molecules. We show that the asymmetry of the barrier length at both sides of the Highest Occupied Molecular Orbital of the ferrocenyl moiety strongly contributes to the rectifying properties of ferrocenyl-alkanethiol based molecular junctions. Furthermore, our results reveal that bound and quasi-bound states play an important role in the charge transport. [ABSTRACT FROM AUTHOR]

Thermal transport in amorphous materials has remained one of the fundamental questions in solid state physics while involving a very large field of applications. Using a heat conduction theory incorporating coherence, we demonstrate that the strong phase correlation between local and non-propagating modes, commonly named diffusons in the terminology of amorphous systems, triggers the conduction of heat. By treating the thermal vibrations as collective excitations, the significant contribution of diffusons, predominantly relying on coherence, further reveals interesting temperature and length dependences of thermal conductivity. The propagation length of diffuson clusters is found to reach the micron, overpassing the one of propagons. The explored wavelike behavior of diffusons uncovers the unsolved physical picture of mode correlation in prevailing models and further provides an interpretation of their ability to transport heat. This work introduces a framework for understanding thermal vibrations and transport in amorphous materials, as well as an unexpected insight into the wave nature of thermal vibrations. [ABSTRACT FROM AUTHOR]

Interestingly, patients with prePMF had an intermediate number of circulating CD34 + cells (median number: 4.4/ l, interquartile range, IQR: 2.9-6.1) between those with ET (2.2/ l, IQR: 1.5-4) and those with overt PMF (21/ l, IQR: 8.5-73). Different number of circulating CD34 + cells in essential thrombocythemia, prefibrotic/early primary myelofibrosis, and overt primary myelofibrosis In conclusion, we showed that the numeration of circulating CD34 + cells can help to distinguish patients with ET, prePMF, or overt PMF. We retrospectively included all patients diagnosed with essential thrombocythemia (ET), prePMF, and overt PMF in our two institutions between January 2017 and July 2020 for whom both a bone marrow biopsy and a measurement of CD34 + cells were performed. [Extracted from the article]

Introduction: The impact of aromatic plants used in cooking on health is indisputable. This study aims to evaluate the in vitro cytotoxicity of Artemia salina, acute and the 28 days subchronic toxicity of X. aethiopica dried fruit used like spice in Togo by oral administration of the extract to female Wistar rats. Results: The A. salina assay showed that the hydroalcoholic extract of X. aethiopica presented any toxicity. The LC50 values of X. aethiopica on brine shrimp were 0.64 ± 0.13 mg/mL. The acute toxicity study revealed neither behavioral disturbances nor death in rats. The lethal dose (DL50) of this extract is greater than 5000 mg/kg body weight. The results of subchronic toxicity showed no significant change in body and organs weight gain in rats at test doses throughout the treatment period. No changes in haematological parameters were observed apart from a significant increase in platelet number at doses of 500 and 1000 mg/kg. Biochemical parameters such as Urea, Creatinine, Triglycerides, Total cholesterol, Serum glutamic pyruvic transaminase (SGPT), C-reactive protein (CRP) and glycemia were not significantly changed. Serum glutamic oxaloacetic transaminase (SGOT) and Alkaline phosphatase (ALP) activities increased at doses of 500/1000 mg/kg and 1000 mg/kg respectively. Creatine Phosphokinase (CPK) activity decrease at the dose of 500 and 1000 mg/kg. Blood electrolytes showed no significant change. The histological sections showed no organ damage. Conclusions: Aqueous extract of X. aethiopica did not lead to any adverse effects in rats after acute and subchronic treatment at 500 and 1000 mg/kg doses. [ABSTRACT FROM AUTHOR]

Junctionless transistors are being considered as one of the alternatives to conventional metal-oxide field-effect transistors. In this work, it is then presented a simulation study of silicon double-gated p-type junctionless transistors compared with its inversion-mode counterpart. The quantum transport problem is solved within the non-equilibrium Green's function formalism, whereas hole-phonon interactions are tackled by means of the self-consistent Born approximation. Our findings show that junctionless transistors should perform as good as a conventional transistor only for ultra-thin channels, with the disadvantage of requiring higher supply voltages in thicker channel configurations. [ABSTRACT FROM AUTHOR]

Junctionless transistors are being considered as one of the alternatives to conventional metal-oxide field-effect transistors. In this work, it is then presented a simulation study of silicon double-gated p-type junctionless transistors compared with its inversion-mode counterpart. The quantum transport problem is solved within the non-equilibrium Green's function formalism, whereas hole-phonon interactions are tackled by means of the self-consistent Born approximation. Our findings show that junctionless transistors should perform as good as a conventional transistor only for ultra-thin channels, with the disadvantage of requiring higher supply voltages in thicker channel configurations. [ABSTRACT FROM AUTHOR]

Anderson localization of thermal phonons has been shown only in few nanostructures with strong random disorder by the exponential decay of transmission to zero and a thermal conductivity maximum when increasing the system length. In this work, we present a path to demonstrate the phonon localization with distinctive features in graded superlattices with short-range order and long-range disorder. A thermal conductivity minimum with system length appears due to the exponential decay of transmission to a non-zero constant, which is a feature of partial phonon localization caused by the moderate disorder. We provide clear evidence of localization through the combined analysis of the participation ratio, transmission, and real-space phonon number density distribution based on our quantum transport simulation. The present work would promote heat conduction engineering by localization via the wave nature of phonons. [ABSTRACT FROM AUTHOR]

We theoretically investigate the impact of uniaxial strain in extremely thin Si and Ge p-type doublegate transistors. Quantum transport modeling is treated using a 6-band k.p Hamiltonian and the nonequilibrium Green's function formalism including phonon scattering. Based on this framework, we analyze the influence of strain on current characteristics considering different transport directions and gate lengths. Our results first confirm the superiority of Ge over Si in long devices (15nm gate length) for which best electrical performances are obtained considering channels along 〈110〉 with a uni-axial compressive strain. For this configuration, Si devices suffer from inter-subband coupling which generates a strong hole-phonon scattering. Material dominance is reversed for shorter devices (7nm gate length) where the small effective masses of Ge deteriorate the off-regime of the nanotransistor regardless of strain and crystallographic options. Due to weaker hole-phonon-scattering, 〈100〉-Si devices with a tensile strain are interestingly found to be more competitive than their 〈110〉-compressive counterparts. These results show that Si is still the most relevant material to reach the ultimate nanometer scale. More importantly, the same tensile strain can be considered to boost performances of both p- and n-type planar transistors which would lead to a significant simplification of the technological strain manufacturing. [ABSTRACT FROM AUTHOR]

Nano-phononic crystals have attracted a great deal of research interest in the field of nanoscale thermal transport due to their unique coherent thermal transport behavior. So far, there have been many advances in the theory and simulation studies of coherent thermal transport in nano-phononic crystals. In this paper, we summarize the state-of-the-art studies in this field from the perspective of coherent thermal transport at low temperatures, minimum thermal conductivity, Anderson localization, in various nanosystems, and in the frame of machine learning driven studies. Each part is specifically presented under different simulation methodologies, in which the background theories are also summarized. Accordingly, the controversies between different methodologies in describing wave-like/coherent and particle-like/incoherent thermal phonons are discussed. Various effects on coherent thermal transport are reviewed, including interface roughness, mass disorder, structural randomness, aperiodic ordering, and temperature effect. Finally, an outlook on the future research on coherent thermal transport in nano-phononic crystals is given. This overview provides fundamental and advanced knowledge to understand the coherent thermal transport in nano-phononic crystals, which will be beneficial to the further understanding of the physical picture of thermal phonons and heat transfer related applications. [ABSTRACT FROM AUTHOR]

Single dopant nanowire transistors can be viewed as the ultimate miniaturization of nano electronic devices. In this work, we theoretically investigate the influence of the electron-phonon coupling on their transport properties using a non-equilibrium Green's function approach in the self-consistent Born approximation. For an impurity located at the center of the wire we find that, at room temperature, acoustic phonons broaden the impurity level so that the bistability predicted in the ballistic regime is suppressed. Optical phonons are found to have a beneficial impact on carrier transport via a phonon-assisted tunneling effect. We discuss the position and temperature dependence of these effects, showing that such systems might be very promising for engineering of ultimate devices. [ABSTRACT FROM AUTHOR]

Purpose: Suspended particulate matter (SPM) transport through rivers is a major vector of nutrients and pollutants to continental shelf areas. To develop efficient sediment management strategies, there is a need to obtain quantitative information on SPM sources. For many years, the geochemical properties of SPM have been commonly used as tracers to identify sediment sources. In large watersheds, with numerous sources, the expected alteration of tracers during their transport requires that their reactivity be taken into account. Materials and methods: To overcome this issue, we tested the use of major and trace element signatures in the residual fraction of SPM, using two different extraction methods. This original fingerprinting approach was applied to the Upper Rhône River basin (~20,000 km2) in order to assess the respective SPM contributions of its main five tributaries (Arve, Ain, Fier, Guiers, and Bourbre Rivers) for contrasted hydrological conditions (base flow periods, flood events and dam flushing). By incorporating element concentrations previously corrected from particle size distribution in a mixing model coupled to Monte Carlo simulations, we estimated the associated uncertainties of the SPM contributions from each tributary. The relative SPM contributions obtained using this fingerprinting approach were compared with those calculated with a 1-D hydro-sedimentary model. Results and discussion: The use of element concentrations, such as Zn, P, Cu, Pb, Mn, or Sr, in the total fraction of SPM as conservative fingerprinting properties was not suitable, since they are mainly bound (> 50%) to reactive carrier phases. By using Ba, Ni, Fe, Mg, Cu, Sr, and V concentrations in the SPM residual fraction, the apportionment modeling of SPM sources was successfully assessed. The fingerprinting approach showed that, in base flow conditions, SPM originated mainly from the Arve River. During dam flushing event, the fingerprinting approach consistently estimated that re-suspended sediments came from the Arve River, while the 1-D hydro-sedimentary model estimated a proportion of re-suspended sediment originating within the Rhône River. Conclusions: This original fingerprinting approach highlighted the relevance of using geochemical properties in the non-reactive fraction of SPM in order to obtain reliable information on spatial sources of SPM in a large river basin. This methodology opens up promising perspectives to better track SPM sources in highly reactive environments such as estuaries/delta or in historical sediment archives. [ABSTRACT FROM AUTHOR]

Haspin is a mitotic protein kinase required for proper cell division by modulating Aurora B kinase localisation and activity as well as histone phosphorylation. Here a series of imidazopyridazines based on the CHR-6494 and Structure Activity Relationship was established. An assessment of the inhibitory activity of the lead structures on human Haspin and several other protein kinases is presented. The lead structure was rapidly optimised using a combination of crystal structures and effective docking models, with the best inhibitors exhibiting potent inhibitory activity on Haspin with IC50 between 6 and 100 nM in vitro. The developed inhibitors displayed anti-proliferative properties against various human cancer cell lines in 2D and spheroid cultures and significantly inhibited the migration ability of osteosarcoma U-2 OS cells. Notably, we show that our lead compounds are powerful Haspin inhibitors in human cells, and did not block G2/M cell cycle transition due to improved selectivity against CDK1/CyclinB. [ABSTRACT FROM AUTHOR]

We present a one-shot current-conserving approach to model the influence of electron-phonon scattering in nano-transistors using the non-equilibrium Green's function formalism. The approach is based on the lowest order approximation (LOA) to the current and its simplest analytic continuation (LOA+AC). By means of a scaling argument, we show how both LOA and LOA+AC can be easily obtained from the first iteration of the usual self-consistent Born approximation (SCBA) algorithm. Both LOA and LOA+AC are then applied to model n-type silicon nanowire field-effect-transistors and are compared to SCBA current characteristics. In this system, the LOA fails to describe electron-phonon scattering, mainly because of the interactions with acoustic phonons at the band edges. In contrast, the LOA+AC still well approximates the SCBA current characteristics, thus demonstrating the power of analytic continuation techniques. The limits of validity of LOA+AC are also discussed, and more sophisticated and general analytic continuation techniques are suggested for more demanding cases. [ABSTRACT FROM AUTHOR]

Based on a self-consistent multi-band quantum transport code including hole-phonon scattering, we compare current characteristics of Si, Ge, and GaAs p-type double-gate transistors. Electronic properties are analyzed as a function of (i) transport orientation, (ii) channel material, and (iii) gate length. We first show that <100>-oriented devices offer better characteristics than their <110>-counterparts independently of the material choice. Our results also point out that the weaker impact of scattering in Ge produces better electrical performances in long devices, while the moderate tunneling effect makes Si more advantageous in ultimately scaled transistors. Moreover, GaAs-based devices are less advantageous for shorter lengths and do not offer a high enough ON current for longer gate lengths. According to our simulations, the performance switching between Si and Ge occurs for a gate length of 12 nm. The conclusions of the study invite then to consider <100>-oriented double-gate devices with Si for gate length shorter than 12 nm and Ge otherwise. [ABSTRACT FROM AUTHOR]

We examined the understanding of emotional speech by deaf children with cochlear implant (CI). Thirty deaf children with CI and 60 typically developing controls (matched on chronological age or hearing age) performed a computerized task featuring emotional prosody, either embedded in a discrepant context or without any context at all. Across the task conditions, the deaf participants with CI scored lower on the prosody-bases responses than their peers matched on chronological age or hearing age. Additionally, we analyzed the effect of age on determining correct prosody-based responses and we found that hearing age was a predictor of the accuracy of prosody-based responses. We discuss these findings with respect to delay in prosody and intermodal processing. Future research should aim to specify the nature of the cognitive processes that would be required to process prosody. [ABSTRACT FROM AUTHOR]

This work presents a theoretical study of the influence of a single donor on the transport properties of silicon nanowire transistors. Using a three-dimensional self-consistent nonequilibrium Green's function approach we find that the donor states induce transitions from resonant to antiresonant Breit-Wigner interferences when increasing the gate or drain voltages. Numerical and analytical calculations demonstrate that these interferences strongly degrade the transistor performances but can also generate a remarkable negative differential resistance behavior. The robustness of this phenomenon with respect to a change of the defect position in the channel is an opportunity to develop novel device properties. [ABSTRACT FROM AUTHOR]

This work presents original nanowire transistor architectures leading to device performance improvement. The influence of channel geometrical patterns on nanowire metal-oxide-semiconductor-field-effect-transistor characteristics is investigated using three-dimensional real-space quantum-mechanical simulations. Our study shows that indented channel improves the on-off current ratio (Ion/Ioff) by 32%. This remarkable result is induced by both quasiresonances in the on-regime and more significantly by the presence of a thicker channel potential barrier in the subthreshold domain. We then demonstrate that an optimized indented channel represents a manufacturable opportunity to have a much better control of short channel effects in nanowire transistors. [ABSTRACT FROM AUTHOR]

Wire feeding can be combined with different heat sources, for example, arc, laser, and electron beam, to enable additive manufacturing and repair of metallic materials. In the case of titanium alloys, the vacuum operational environment of electron beam systems prevents atmospheric contamination during high-temperature processing and ensures high performance and reliability of additively manufactured or repaired components. In the present work, the feasibility of developing a repair process that emulates refurbishing an "extensively eroded" fan blade leading edge using wire-feed electron beam additive manufacturing technology was examined. The integrity of the Ti6Al4V wall structure deposited on a 3 mm thick Ti6Al4V substrate was verified using X-ray microcomputed tomography with a three-dimensional reconstruction. To understand the geometrical distortion in the substrate, three-dimensional displacement mapping with digital image correlation was undertaken after refurbishment and postdeposition stress relief heat treatment. Other characteristics of the repair were examined by assessing the macro- and microstructure, residual stresses, microhardness, tensile and fatigue properties, and static and dynamic failure mechanisms. [ABSTRACT FROM AUTHOR]

Focuses on a study which determined a scanned point source-point receiver technique, based on laser generation and detection of acoustic waves, to measure the stiffness coefficients of anisotropic materials. Discussion on recovering of stiffness coefficients; Information on silicon crystal; Methodology of the study; Results and discussion.

Ballistic transport in monolayer Germanane MOSFETs is investigated for high-performance (HP) applications. Characteristics of both n- and p-type transistors having channel lengths of 7, 5, and 3 nm are studied and compared against the International Technology Roadmap for Semiconductor (ITRS) target of 2028. Our simulation approach is based on a self-consistent quantum ballistic transport model within the framework of the nonequilibrium Green's function formalism and relies on a single-band and a two-band k · p Hamiltonian for n- and p-type channels, respectively. We found that, even for a gate length scaled down to 3 nm, the ON current (ION) in n- and p-MOSFETs for a fixed OFF current IOFF = 100 nA/µm is as high as ~890 and 700 µA/µm, respectively. For longer channel lengths, the p-MOSFET can outperform the n-MOSFET in terms of ION requirements, as the direct source-to-drain tunneling gets suppressed. Other performance metrics, including gate capacitance, intrinsic switching delay, and switching energy, have also been calculated and found to be comparable to the ITRS 2028 HP technology requirements. [ABSTRACT FROM AUTHOR]

We investigate the effect of the geometrical model adopted for the gate electrode and for the insulator enveloping the access regions on the full-quantum simulation of ultrascaled nanowire FETs (NW-FETs). We compare the results obtained in the "minimal" geometry commonly used in simulations with those obtained in a more realistic one, able to fully account for the gate fringing effects. We evaluate the impact of the model geometry on the static performance of NW-FETs and discuss the interplay with the surface roughness and the random distribution of dopants. We find that the ION/ IOFF ratio evaluated in the minimal geometry can be remarkably underestimated in short devices, notably in the case of small length-to-width ratio. The roughness-induced current degradation and the sensitivity to the surface roughness variability can also suffer from nonnegligible underestimationswhen evaluated in this geometry. Finally, we point out that an inaccurate description of the device electrostatics is expected to result in an overestimationof the sensitivity to the doping-induced variability. [ABSTRACT FROM AUTHOR]

Recently, a new population of resident cardiac stem cells (CSCs) positive for the W8B2 marker has been identified. These CSCs are considered to be an ideal cellular source to repair myocardial damage after infarction. However, the electrophysiological profile of these cells has not been characterized yet. We first establish the conditions of isolation and expansion of W8B2+ CSCs from human heart biopsies using a magnetic sorting system followed by flow cytometry cell sorting. These cells display a spindle‐shaped morphology, are highly proliferative, and possess self‐renewal capacity demonstrated by their ability to form colonies. Besides, W8B2+ CSCs are positive for mesenchymal markers but negative for hematopoietic and endothelial ones. RT‐qPCR and immunostaining experiments show that W8B2+ CSCs express some early cardiac‐specific transcription factors but lack the expression of cardiac‐specific structural genes. Using patch clamp in the whole‐cell configuration, we show for the first time the electrophysiological signature of BKCa current in these cells. Accordingly, RT‐PCR and western blotting analysis confirmed the presence of BKCa at both mRNA and protein levels in W8B2+ CSCs. Interestingly, BKCa channel inhibition by paxilline decreased cell proliferation in a concentration‐dependent manner and halted cell cycle progression at the G0/G1 phase. The inhibition of BKCa also decreased the self‐renewal capacity but did not affect migration of W8B2+ CSCs. Taken together, our results are consistent with an important role of BKCa channels in cell cycle progression and self‐renewal in human cardiac stem cells. [ABSTRACT FROM AUTHOR]

Ultrasonic guided waves are particularly interesting for SHM applications because they have the ability to propagate long distances with minimal attenuation. Using the baseline subtraction approach, the signal from a defect free structure is subtracted from the actual monitoring signal to detect and characterize defects. Low frequency guided wave SHM and the interaction of the fundamental guided wave modes with various types of defect are well documented in the literature. There are, however, only a very limited number of studies on high order modes. High frequency guided waves may enable the detection of smaller cracks relative to conventional low frequency guided wave SHM. The main difficulty at high frequency is the existence of several modes with different velocities. This study investigates the scattering of high frequency Lamb waves around a through-thickness hole with a view to developing a highly sensitive SHM system for safety-critical components. A 3D finite element model of a 305 × 305 × 1.6 mm aluminum plate was used to determine the scattered field generated by cracks on the circumference of a through-thickness hole in the middle of the plate. Crack properties such as orientation, length and depth were studied. A subset of the finite element simulations were validated against experimental results. The experimental setup comprised a classic contact piezoelectric transducer bonded on the side of the plate and a laser interferometer detector. [ABSTRACT FROM AUTHOR]

Dodoneine (Ddn) is one of the active compounds identified from Agelanthus dodoneifolius, which is a medicinal plant used in African pharmacopeia and traditional medicine for the treatment of hypertension. In the context of a scientific program aiming at discovering new hypotensive agents through the original combination of natural product discovery and superacid chemistry diversification, and after evidencing dodoneine's vasorelaxant effect on rat aorta, superacid modifications allowed us to generate original analogues which showed selective human carbonic anhydrase III (hCA III) and L-type Ca2+ current inhibition. These derivatives can now be considered as new lead compounds for vasorelaxant therapeutics targeting these two proteins. [ABSTRACT FROM AUTHOR]

We theoretically investigate GaN/InGaN/GaN tunnel junctions grown along the wurtzite c-axis. We developed a dedicated quantum electronic transport model based on an 8-band k.p Hamiltonian coupled to the non-equilibrium Green's function formalism. We first show that the transmission is dominated by quantum states localized at the heterojunction. We also confirm that, for a thin InGaN layer, current strongly increases with doping. On the other hand, for thick InGaN layers (>8 nm), our results show an unexpected low impact of doping on current. In this latter case, the spontaneous and the piezoelectric polarizations reduce the tunnel-barrier width to the InGaN layer thickness. We conclude that quantum electronic transport in such tunnel junctions is mainly controlled by interfaces with both polarizations and localized states. [ABSTRACT FROM AUTHOR]

We investigate the impact of the so-called local, i.e., diagonal, approximation for the electron-photon scattering self-energy, within the nonequilibrium Green's function formalism. We report on three different systems to show that the local approximation may dramatically degrade expected selection rules, but that this degradation has minor impacts on the physical properties of realistic systems in which other scattering processes are assumed. [ABSTRACT FROM AUTHOR]

In this article, the author discusses his work and texture on the materials of leather bookbinding and states that leather depends on the animal it originates from and how it is tanned, he likes working with vegetable-tanned calf leather and important aspect for his design work is color.