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The precise arrangement and nature of atoms drive electronic phase transitions in condensed matter. To explore this tenuous link, we developed a true biaxial mechanical deformation device working at cryogenic temperatures, compatible with x-ray diffraction and transport measurements, well adapted to layered samples. Here we show that a slight deformation of TbTe 3 can have a dramatic influence on its Charge Density Wave (CDW), with an orientational transition from c to a driven by the a / c parameter, a tiny coexistence region near a  =  c , and without space group change. The CDW transition temperature T c displays a linear dependence with a / c − 1 while the gap saturates out of the coexistence region. This behaviour is well accounted for within a tight-binding model. Our results question the relationship between gap and T c in RTe 3 systems. This method opens a new route towards the study of coexisting or competing electronic orders in condensed matter. Previous studies of the effects of strain on charge density waves have mostly focused on uniaxial strain. Here the authors use a biaxial-strain device to demonstrate switching of the charge density wave orientation, as well as a strong linear increase of the transition temperature while the gap seems to saturate.

Alcoholic fermentation of grape must is a complex process, involving several yeast genera and species. The early stages in fermentation are dominated by non- Saccharomyces yeasts that are gradually replaced by the Saccharomyces cerevisiae species, which takes over the fermentation. Quantitative studies have reported the influence of non- Saccharomyces yeast species on wine quality and evaluated their biotechnological interest. The industrial yeast market, which, until recently, exclusively focused on S . cerevisiae , now offers S . cerevisiae /non- Saccharomyces (including Torulaspora delbrueckii ) multi-starters. The development of these new mixed industrial starters requires a better understanding of the interaction mechanisms between yeast populations in order to optimize the aromatic impact of the non- Saccharomyces yeast while ensuring complete alcoholic fermentation thanks to S . cerevisiae . For this purpose, a new double-compartment fermentor was designed with the following characteristics: (1) physical separation of two yeast populations, (2) homogeneity of the culture medium in both compartments, (3) fermentation kinetics monitored by weight loss due to CO 2 release, and (4) independent monitoring of growth kinetics in the two compartments. This tool was used to compare mixed inoculations of S . cerevisiae / T . delbrueckii with and without physical separation. Our results revealed that physical contact/proximity between S . cerevisiae and T . delbrueckii induced rapid death of T . delbrueckii , a phenomenon previously described and attributed to a cell–cell contact mechanism. In contrast, when physically separated from S . cerevisiae , T . delbrueckii maintained its viability and its metabolic activity had a marked impact on S . cerevisiae growth and viability. The double fermentor is thus a powerful tool for studying yeast interactions. Our findings shed new light on interaction mechanisms described in microorganism populations.

In this paper we introduce the 3D physics-based numerical simulations (PBS) of ground motion during the Nov 11, 2019, M W 4.9 Le Teil earthquake, which occurred in a low-to-moderate seismicity area in the South-East of France, within the Rhône river valley, which hosts several operating nuclear installations. The numerical code SPEED, developed at Politecnico di Milano, Italy, was used to produce the PBS. After introducing the criteria to construct the numerical model, based on the relatively limited data available, a numerical convergence test was made to identify the frequency range for accurate simulations. Furthermore, the performance of the numerical results against the available strong motion records was assessed quantitatively using Goodness-of-fit (GoF) measures. According to the GoF scores, a good-to-excellent agreement was found on the horizontal components up to 8 Hz, showing that, even without a very detailed 3D numerical model of the medium, that would imply detailed knowledge of the basin shape, of the bedrock-to-basin impedance ratio, as well as of the damping ratio in the basin and its dependence on frequency, the PBS may provide realistic broadband predictions of earthquake ground motion. Nevertheless, as shown by the poorer performance on the vertical component, the high-frequency limitations of PBS, also in relation to the energy radiated by the kinematic source model, is still an issue to be carefully addressed. In spite of these limitations, the results obtained in this work demonstrate that PBS, if suitably calibrated and validated, can be either an alternative or a useful complement to empirical ground motion models, especially in those cases where the region- and site-specific features of ground shaking, including near-source conditions, are typically not accounted for by ergodic empirical models, such as for the seismic risk evaluation of large urban areas and/or of strategic structures, infrastructures and industrial plants.

Using atomistic calculations with a Finnis-Sinclair type potential and molecular statics and dynamics methods, we performed a series of deformation tests on nanocrystallised tungsten samples presenting various microstructures; we calculated the elastic constants of polycrystalline tungsten for average grain diameters ranging from 2.7 to 6.7 nm. The results show that both Young’s and the shear moduli decrease by over 60% as the average grain diameter decreases below 3 nm. This diminution appears to be highly correlated to the grain boundary volume fraction. The results are compared to conclusions from other authors.

Heat waves, defined as events associating high temperatures with severe drought, are expected to become increasingly recurrent. Research has focused heavily on the impacts of drought and temperature increase on soil functioning and microbial diversity, but little attention has been paid to soil microbial community responses to combined heat−drought stresses. Heat waves, which combine heat and drought stresses, may induce different microbial responses to those observed in studies focusing on heat or drought alone. Microbial recovery strategies to with-stand heat−drought conditions, along with patterns of microbial functional redundancy and complex interactions with the soil physical−chemical−biological interface may have marked effects on soil ecosystem functioning, particularly in agroecosystems through the rhizosphere. To better understand how heat waves affect soil ecosystem functioning, we advocate the development of mechanistic approaches integrating individual to community level and biophysicochemical studies on the indirect effects of combined heat−drought stresses in microbial communities, observed through soil environment parameters in experimental and field studies. The challenge will be to define trait-based functional indicators of the microbial community response to heat waves, particularly the potential interrelatedness between the traits responsible for tolerance to drought and heat.

Defining the drug-induced neuroadaptations specifically associated with the behavioral manifestation of addiction is a daunting task. To address this issue, we used a behavioral model that differentiates rats controlling their drug use (Non-Addict-like) from rats undergoing transition to addiction (Addict-like). Dysfunctions in prefrontal cortex (PFC) synaptic circuits are thought to be responsible for the loss of control over drug taking that characterizes addicted individuals. Here, we studied the synaptic alterations in prelimbic PFC (pPFC) circuits associated with transition to addiction. We discovered that some of the changes induced by cocaine self-administration (SA), such as the impairment of the endocannabinoid-mediated long-term synaptic depression (eCB-LTD) was similarly abolished in Non-Addict- and Addict-like rats and thus unrelated to transition to addiction. In contrast, metabotropic glutamate receptor 2/3-mediated LTD (mGluR2/3-LTD) was specifically suppressed in Addict-like rats, which also show a concomitant postsynaptic plasticity expressed as a change in the relative contribution of AMPAR and NMDAR to basal glutamate-mediated synaptic transmission. Addiction-associated synaptic alterations in the pPFC were not fully developed at early stages of cocaine SA, when addiction-like behaviors are still absent, suggesting that pathological behaviors appear once the pPFC is compromised. These data identify specific synaptic impairments in the pPFC associated with addiction and support the idea that alterations of synaptic plasticity are core markers of drug dependence.

Background and objectives: Gut hormones secreted by enteroendocrine cells (EECs) play a major role in energy regulation. Differentiation of EEC is controlled by the expression of basic helix–loop–helix (bHLH) transcription factors. High-fat (HF) feeding alters gut hormone levels; however, the impact of HF feeding on bHLH transcription factors in mediating EEC differentiation and subsequent gut hormone secretion and expression is not known. Methods: Outbred Sprague–Dawley rats were maintained on chow or HF diet for 12 weeks. Gene and protein expression of intestinal bHLH transcription factors, combined with immunofluorescence studies, were analyzed for both groups in the small intestine and colon. Gut permeability, intestinal lipid and carbohydrate transporters as well as circulating levels and intestinal protein expression of gut peptides were determined. Results: We showed that HF feeding resulted in hyperphagia and increased adiposity. HF-fed animals exhibited decreased expression of bHLH transcription factors controlling EEC differentiation (MATH1, NGN3, NEUROD1) and increased expression of bHLH factors modulating enterocyte expression. Furthermore, HF-fed animals had decreased number of total EECs and L-cells. This was accompanied by increased gut permeability and expression of lipid and carbohydrate transporters, and a decrease in circulating and intestinal gut hormone levels. Conclusions: Taken together, our results demonstrate that HF feeding caused decreased secretory lineage (that is, EECs) differentiation through downregulation of bHLH transcription factors, resulting in reduced EEC number and gut hormone levels. Thus, impaired EEC differentiation pathways by HF feeding may promote hyperphagia and subsequent obesity.

Tungsten-titanium (WTi) thin films are known as potential adhesion promoters and diffusion barriers. The barrier efficiency of WTi thin films against indium (In) diffusion was experimentally studied by x-ray diffraction (XRD) measurements during in situ annealing. Specific multilayered samples were designed to estimate the diffusion barrier properties using the Ni/In system. These diffusion samples were made up of a 100-nm-thick WTi layer prepared by magnetron sputtering from an alloyed target (W:Ti ≈ 70:30 at.%), sandwiched between Ni and Au/In layers. WTi film microstructures were observed to depend on the working pressure. Diffusion barrier breakdown was monitored upon annealing by the formation of intermetallic compounds (IMC) (intermixing between Ni and In). Annealing was performed at temperatures of 573 K, 623 K, and 673 K (homologous temperatures T / T m In ≃ 1.34 , 1.45 , and 1.57, respectively) and under primary vacuum. The diffusion coefficients of In in WTi were determined. The correlation between WTi film microstructure and diffusion barrier efficiency was established. Better diffusion barrier performance was obtained for WTi films with dense microstructure associated with a compressive residual stress state. Hence, tuning the sputtering conditions allows significant improvement of barrier performance against diffusion through a change of the film microstructure.

We are developing a high-resolution printing technique based on transferring a pattern from an elastomeric stamp to a solid substrate by conformal contact. This is an attempt to enhance the accuracy of classical printing to a precision comparable with optical lithography, creating a low-cost, large-area, high-resolution patterning process.

The gene dosage inequality between females with two X-chromosomes and males with one is compensated for by X-chromosome inactivation (XCI), which ensures the silencing of one X in every somatic cell of female mammals. XCI in humans results in a mosaic of two cell populations: those expressing the maternal X-chromosome and those expressing the paternal X-chromosome. We have previously shown that the degree of mosaicism (the X-inactivation pattern) in a Canadian family is directly related to disease severity in female carriers of the X-linked recessive bleeding disorder, haemophilia A. The distribution of X-inactivation patterns in this family was consistent with a genetic trait having a co-dominant mode of inheritance, suggesting that XCI choice may not be completely random. To identify genetic elements that could be responsible for biased XCI choice, a linkage analysis was undertaken using an approach tailored to accommodate the continuous nature of the X-inactivation pattern phenotype in the Canadian family. Several X-linked regions were identified, one of which overlaps with a region previously found to be linked to familial skewed XCI. SA2 , a component of the cohesin complex is identified as a candidate gene that could participate in XCI through its association with CTCF.