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International audience; For the first time, a Zn1.1Ga1.8Ge0.1O4 transparent spinel ceramic has been fully densified by spark plasma sintering. XRD measurements show that this ceramic is composed of a pure cubic spinel phase. SEM analysis revealed a homogeneous and dense microstructure with the average grain size being 200 ± 100 nm. The transmittance of these fine-grained ceramics reached 70 % in the visible range and is very close to 80 % at 2 µm, thus close to the Tmax value deduced from the measurement of the refractive index. The ceramics exhibit excellent mechanical properties with a Young modulus of 222 GPa, a Vickers hardness of 14.25 GPa and a thermal conductivity of 7.3 W.m−1. K−1. By doping with Cr3+ ions, transparent Zn1.1Ga1.8Ge0.1O4 ceramics present both a red luminescence and a long-lasting afterglow during several minutes. Moreover, a near infrared broadband emission at 1.3 µm is also achieved with Ni2+ ions.

Monogamous marriage, sometimes called “the bedrock of society,” still carries an apparent “halo” of moral superiority as a relationship structure. In contrast, consensual non-monogamous (CNM) configurations are stigmatized. Research indicates a connection between stigma, stress, and negative health outcomes, despite CNM comparing favorably with monogamy. The present study uses interviews to explore minority stress and resilience among individuals in CNM relationships. Participants experienced structural stigma as erasure, and interpersonal stigma as erasure and educational/emotional work. They also describe complex enmeshment between their relationship minority status and other aspects of their sexual and gender identities. Strategic disclosure and concealment were important management tools. Furthermore, managing individual (internalized) stigma was described as unlearning mononormative bias and surrounding oneself with supportive peers/allies. The strongest motivator for perseverance was the steadfast conviction that the advantages of CNM outweighed the challenges.

Non-contacting laser ultrasound is used to measure Young’s modulus, shear modulus, and Poisson’s ratio as functions of temperature for Alloys 617 and 709. These alloys are of interest for structural applications in advanced nuclear reactors. Design rules for the construction of elevated-temperature nuclear components are presented in Section III, Division 5 of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV) Code. The ASME B&PV Code for each material provides Young’s modulus values tabulated as a function of temperature and a single, temperature-independent Poisson’s ratio value. Elastic properties characterized by laser ultrasonics for Alloy 617 are in good agreement with data collected using an American Society for Testing and Materials (ASTM) standard resonant frequency technique and values reported from literature, demonstrating its accuracy. The shear modulus and Poisson’s ratio as functions of temperature for Alloy 709 have not been reported previously. Laser ultrasonics is well suited for determining temperature-dependent elastic properties, and the method offers the ability to perform measurements on small irregularly shaped specimens.

Peatlands contain a significant fraction of global soil carbon, but how these reservoirs will respond to the changing climate is still relatively unknown. A global picture of the variations in peat organic matter chemistry will aid our ability to gauge peatland soil response to climate. The goal of this research is to test the hypotheses that 1) peat carbohydrate content, an indicator of soil organic matter reactivity, will increase with latitude and decrease with mean annual temperatures (MAT), 2) while peat aromatic content, an indicator of recalcitrance, will vary inversely, and 3) elevation will have a similar effect to latitude. We used Fourier Transform Infrared Spectroscopy (FTIR) to examine variations in the organic matter functional groups of 1034 peat samples collected from 10-20, 30-40, and 60-70 cm depths at 165 individual sites across a latitudinal gradient of 79˚N to 65˚S and from elevations of 0 to 4773 meters. Carbohydrate contents of high latitude peat were significantly greater than peat originating near the equator, while aromatic content showed the opposite trend. For peat from similar latitudes but different elevations, the carbohydrate content was greater and aromatic content was lower at higher elevations. Higher carbohydrate content at higher latitudes indicates a greater potential for mineralization, whereas the chemical composition of low latitude peat is consistent with their apparent relative stability in the face of warmer temperatures. The combination of low carbohydrates and high aromatics at warmer locations near the equator suggests the mineralization of high latitude peat until reaching recalcitrance under a new temperature regime.

Vibrio alginolyticus and Vibrio (Aliivibrio) fischeri are Gram‐negative bacteria found globally in marine environments. During the past decade, studies have shown that certain Gram‐negative bacteria, including Vibrio species (cholerae, parahaemolyticus, and vulnificus) are capable of using exogenous polyunsaturated fatty acids (PUFAs) to modify the phospholipids of their membrane. Moreover, exposure to exogenous PUFAs has been shown to affect certain phenotypes that are important factors of virulence. The purpose of this study was to investigate whether V. alginolyticus and V. fischeri are capable of responding to exogenous PUFAs by remodeling their membrane phospholipids and/or altering behaviors associated with virulence. Thin‐layer chromatography (TLC) analyses and ultra‐performance liquid chromatography‐electrospray ionization mass spectrometry (UPLC/ESI‐MS) confirmed incorporation of all PUFAs into membrane phosphatidylglycerol and phosphatidylethanolamine. Several growth phenotypes were identified when individual fatty acids were supplied in minimal media and as sole carbon sources. Interestingly, several PUFAs acids inhibited growth of V. fischeri. Significant alterations to membrane permeability were observed depending on fatty acid supplemented. Strikingly, arachidonic acid (20:4) reduced membrane permeability by approximately 35% in both V. alginolyticus and V. fischeri. Biofilm assays indicated that fatty acid influence was dependent on media composition and temperature. All fatty acids caused decreased swimming motility in V. alginolyticus, while only linoleic acid (18:2) significantly increased swimming motility in V. fischeri. In summary, exogenous fatty acids cause a variety of changes in V. alginolyticus and V. fischeri, thus adding these bacteria to a growing list of Gram‐negatives that exhibit versatility in fatty acid utilization and highlighting the potential for environmental PUFAs to influence phenotypes associated with planktonic, beneficial, and pathogenic associations., Bacterial utilization of fatty acids continues to evolve as a practical strategy for environmental adaptation, providing energy currency, ingredients for membrane construction, and cues for behavioral modification. Here, we add two members of the family Vibrionaceae, Vibrio alginolyticus and Aliivibrio fischeri, that scavenge a variety of polyunsaturated fatty acids (PUFAs), as evidenced by incorporation into membrane phospholipids and orchestration of phenotypic responses associated with growth, motility, and biofilm formation. Our findings highlight the differential exploitation of PUFAs by two related genera occupying distinct ecological niches, suggesting species‐specific responses to exogenous fatty acids for survival in planktonic, symbiotic, and pathogenic habitats.

International audience

We report on the discovery and validation of TOI 813b (TIC 55525572 b), a transiting exoplanet identified by citizen scientists in data from NASA's Transiting Exoplanet Survey Satellite (TESS) and the first planet discovered by the Planet Hunters TESS project. The host star is a bright (V = 10.3 mag) subgiant ($R_\star=1.94\,R_\odot$, $M_\star=1.32\,M_\odot$). It was observed almost continuously by TESS during its first year of operations, during which time four individual transit events were detected. The candidate passed all the standard light curve-based vetting checks, and ground-based follow-up spectroscopy and speckle imaging enabled us to place an upper limit of $2 M_{Jup}$ (99 % confidence) on the mass of the companion, and to statistically validate its planetary nature. Detailed modelling of the transits yields a period of $83.8911_{ - 0.0031 } ^ { + 0.0027 }$ days, a planet radius of $6.71 \pm 0.38$ $R_{\oplus}$, and a semi major axis of $0.423_{ - 0.037 } ^ { + 0.031 }$ AU. The planet's orbital period combined with the evolved nature of the host star places this object in a relatively under-explored region of parameter space. We estimate that TOI-813b induces a reflex motion in its host star with a semi-amplitude of $\sim6$ ms$^{-1}$, making this system a promising target to measure the mass of a relatively long-period transiting planet., Accepted for publication in MNRAS (16 pages, 10 figures, 3 tables)

The main objective of this study is to improve thermal insulation of fired clay bricks through addition of wooden furniture waste. The effect of the nature and the amount (5 or 10 wt%) of wooden furniture waste on the properties of the final porous fired brick prepared by extrusion was assessed though measurements of mass loss, drying and sintering shrinkage, porosity, bulk density and thermal conductivity. Results showed that incorporation of wooden furniture waste into the clay mixture yielded increase of porosity after firing and hence decrease of thermal conductivity. For example, addition of 10 wt% wood waste yielded a pore volume fraction of 47% with a conductivity of 0.42 W m−1 K−1. Moreover, due to orientation of the clay platelets, the anisotropy in thermal conductivity was significant, ranging from a ratio of 1.1–1.5.

In order to investigate drying mechanisms at different stages, the distribution of water within the ceramic green bodies at different scales has been examined. The experimental measurements, using a simple weighing technique and Magnetic Resonance Imaging (MRI), show that during the first stage of drying involving shrinkage the material is constituted of uniquely solid and water with no gradient in water content within the sample. Then, during the second stage of drying, significant differences of water content as a function of position appear. As a complement, at the grain scale, observations using environmental scanning electron microscopy were made giving useful information on the solid–liquid–gas interfaces in the near surface part of the green body. Finally, the gradients in the water distribution were exploited to make a simple estimate of the diffusion coefficient of water with its dependence on the moisture content.

NoFap is a community of mostly heterosexual men abstaining from what they see as an addictive cycle of pornography, masturbation, and orgasm, induced by the exploitation of innate male urges by the pornography industry. In the general population, increased masturbation and consumption of pornography are associated with psychological factors including low affect, loneliness, and boredom, all of which may be exacerbated by the lockdown/social distancing measures adopted in response to the Covid-19 pandemic. The present study explores how the NoFap community has responded to the pandemic through discourse analysis of an online message board. We identify four key themes: i) I let go in lockdown, ii) the opportunity of lockdown, iii) testing the parameters of NoFap, and iv) community cohesion. Each is defined and discussed. Combined they illustrate a digital community struggling to honor its meritocratic masculine ideals in the face of challenging circumstances.

Open ceramics 6, 100118 (2021). doi:10.1016/j.oceram.2021.100118 special issue: "Young Ceramists in the Spotlight / Edited ba Maria Canillas Perez, Erkka Frankberg, Andraž Kocijan, Marie Lasgordeix, Antonia Ressler, Laura Tiainen", Published by Elsevier, Amsterdam

The evolution of shrinkage and mass during drying of kaolin and alumina green bodies was characterized. Standard practise uses a position sensor with simultaneous mass measurement. In this work an optical method was developed to follow shrinkage in two orthogonal directions. Green body samples were made by pressing of ceramic pastes. Results have been compared through the well known Bigot curves which show two distinct stages. First a linear shrinkage with the evaporated water loss is observed. Then in the second stage with further water loss, negligible dimension changes occur. For each material, the overall shrinkage values are identical in the two directions parallel to the pressing axis, but higher in the pressing direction. This difference is related to the shaping method yielding a preferential orientation of grains. Anisotropy in shrinkage is more significant for kaolin with tabular shaped grains compared to the more isometric grains of alumina.

Purpose The non-uniform fast Fourier transform (NUFFT) involves interpolation of non-uniformly sampled Fourier data onto a Cartesian grid, an interpolation that is slowed by complex, non-local data access patterns. A faster NUFFT would increase the clinical relevance of the plethora of advanced non-Cartesian acquisition methods. Methods Here we customize the NUFFT procedure for a radial trajectory and GPU architecture to eliminate the bottlenecks encountered when allowing for arbitrary trajectories and hardware. We call the result TRON, for TRajectory Optimized NUFFT. We benchmark the speed and accuracy TRON on a Shepp-Logan phantom and on whole-body continuous golden-angle radial MRI. Results TRON was 6-30× faster than the closest competitor, depending on test data set, and was the most accurate code tested. Conclusions Specialization of the NUFFT algorithm for a particular trajectory yielded significant speed gains. TRON can be easily extended to other trajectories, such as spiral and PROPELLER. TRON can be downloaded at http://github.com/davidssmith/TRON.

BACKGROUND Computed tomography (CT) and spirometry are the current standard methods for assessing lung anatomy and pulmonary ventilation, respectively. However, CT provides limited ventilation information and spirometry only provides global measures of lung ventilation. Thus, a method that can enable simultaneous examination of lung anatomy and ventilation is of clinical interest. PURPOSE To develop and test a 4D respiratory-resolved sparse lung MRI (XD-UTE: eXtra-Dimensional Ultrashort TE imaging) approach for simultaneous evaluation of lung anatomy and pulmonary ventilation. STUDY TYPE Prospective. POPULATION In all, 23 subjects (11 volunteers and 12 patients, mean age = 63.6 ± 8.4). FIELD STRENGTH/SEQUENCE 3T MR; a prototype 3D golden-angle radial UTE sequence, a Cartesian breath-hold volumetric-interpolated examination (BH-VIBE) sequence. ASSESSMENT All subjects were scanned using the 3D golden-angle radial UTE sequence during normal breathing. Ten subjects underwent an additional scan during alternating normal and deep breathing. Respiratory-motion-resolved sparse reconstruction was performed for all the acquired data to generate dynamic normal-breathing or deep-breathing image series. For comparison, BH-VIBE was performed in 12 subjects. Lung images were visually scored by three experienced chest radiologists and were analyzed by two observers who segmented the left and right lung to derive ventilation parameters in comparison with spirometry. STATISTICAL TESTS Nonparametric paired two-tailed Wilcoxon signed-rank test; intraclass correlation coefficient, Pearson correlation coefficient. RESULTS XD-UTE achieved significantly improved image quality compared both with Cartesian BH-VIBE and radial reconstruction without motion compensation (P

Design of high performance materials for thermal insulation or heat sinking requires understanding of the mechanisms controlling heat flow. The effect of grain size on the effective thermal conductivity of porous alumina ceramics has been investigated. After uniaxial pressing of a fine α-alumina powder, control of firing temperature and duration yielded ceramics with variations in grain size. Values of thermal conductivity corresponding to equivalent 100% dense ceramics were determined from laser flash measurements using Landauer’s relation to take porosity into account. These exhibited a strong decrease from 33 W m−1 K−1, for grain sizes larger than 2 μm, down to 8 W m−1 K−1 for an average grain size of 0.25 μm. A method to separate the contributions of localized thermal resistance (Kapitza resistance) at grain boundaries and grain conductivity for each sample is presented. The larger grain size samples (>0.5 μm) yield values for the effective grain boundary thermal resistance in the range 0.6–0.8 × 10−8 m2 K W−1 and a grain conductivity close to 35 W m−1 K−1. For smaller grain samples (

Alloy 709 (UNS S31025) has shown enhanced performance, particularly in creep strength, over current generation high temperature structural materials, specifically Type 316 stainless steel and Grade 91. Accurate knowledge of the thermal properties of the material is important to design efficient systems and to allow calculation of thermally induced stresses and stress gradients. Thermal diffusivity, thermal conductivity, specific heat capacity, and coefficients of thermal expansion have been determined for Alloy 709 as a function of temperature in the range of 20–850 °C. The results do not vary significantly for the three heats of Alloy 709 tested, and compare well with those reported for other high Cr, high Ni austenitic stainless steels. Deviations from monotonic behavior have been observed for the specific heat capacity and to a lesser degree for the thermal conductivity, while the thermal expansion and thermal diffusivity increase nearly linearly with increasing temperature.

1. The Chinese brake fern (Pteris vittata L.; Pteridaceae) can accumulate up to 27 000 mg kg−1 dry wt. of arsenic (As) from the soil into its above-ground biomass. They may use this As to deter invertebrate threats. 2. This study explored how As concentrations [As] in the fern, and in soil associated with the fern, influenced the abundance and composition of various invertebrates. 3. Populations of P. vittata were identified in the field. Soils from the base of the fern and from 3 m away of each plant were collected and pitfall traps were installed. Soil and fern arsenic concentrations ([As]) were measured via inductively coupled plasma mass spectrometry and invertebrates were identified to order and classified by feeding guild. 4. Increased [As] did not affect all feeding guilds and orders equally. For example, individual herbivore abundance did not decrease as [As] increased, but predator abundance did. In many cases, the impact of soil [As] on invertebrates depended on the distance from the fern. Fern [As] also influenced components of the community, but only at 3 m away from the fern. Furthermore, the abundances of many invertebrate groups were higher beneath the fern, where [As] was higher. 5. These results suggest that hyperaccumulated As can impact the invertebrate community, but the defensive benefits of hyperaccumulation are more complex than have been previously described. The authors advocate that future studies examining the potential defensive benefits of hyperaccumulation should do so in a natural setting that incorporates this complexity and invertebrate richness.

In order to provide a thermal barrier in an arid environment, highly reflective coatings were deposited on porous substrates made of natural raw materials from Saudi Arabia. Although highly reflective coatings inhibit heat absorption from the incoming sunlight, the body of conventional ceramic tiles warms up to environmental temperature through conduction, convection and radiation. A strategy to reduce the penetration of this heat into the building is to use a highly porous substrate, which reduces the thermal conductivity of the tile, coupled with a highly reflective glaze. The approach leads to the concept of “cool” tiles, aimed at improving the thermal efficiency of buildings. The present paper provides a first example, based on layered wollastonite-hardystonite glass-ceramics developed by double pressing of glass powders and additives followed by sinter-crystallization.

Diagnosis of asthma in obese individuals frequently relies on clinical history, as airflow by spirometry may remain normal. This study hypothesised that obese subjects with self-reported asthma and normal spirometry will demonstrate distinct clinical characteristics, metabolic comorbidities and enhanced small airway dysfunction as compared with healthy obese subjects. Spirometry, plethysmography and oscillometry data pre/post-bronchodilator were obtained in 357 obese subjects in three groups as follows: no asthma group (n=180), self-reported asthma normal spirometry group (n=126), and asthma obstructed spirometry group (n=51). To assess the effects of obesity related to reduced lung volume, oscillometry measurements were repeated during a voluntary inflation to predicted functional residual capacity (FRC). Dyspnoea was equally prevalent in all groups. In contrast, cough, wheeze and metabolic comorbidities were more frequent in the asthma normal spirometry and asthma obstructed spirometry groups versus the no asthma group (p, Obese subjects with self-reported asthma have exaggerated small airway dysfunction even when spirometric airflow is normal. Cough and wheeze are associated with metabolic comorbidities providing a milieu with impact on small airway function. https://bit.ly/2VFrA9O

PURPOSE: Slice-selective, gradient-crushed, transient-state sequences such as those used in magnetic resonance fingerprinting (MRF) relaxometry are sensitive to slice profile effects. While balanced steady-state free precession MRF profile effects have been studied, less attention has been given to gradient-crushed MRF forms. Extensions of the extended phase graph (EPG) formalism are proposed, called slice-selective EPG (ssEPG), that model slice profile effects. THEORY AND METHODS: The hard-pulse approximation to slice-selective excitation in the spatial domain is reformulated in k-space. Excitation is modeled by standard EPG shift and transition operators. This ssEPG modeling is validated against Bloch simulations and phantom slice profile measurements. ssEPG relaxometry accuracy and variability are compared with other EPG methods in phantoms and human leg in vivo. The role of ΔB(0) interactions with slice profile and gradient crushers are investigated. RESULTS: Simulations and slice profile measurements show that ssEPG can model highly dynamic slice profile effects of gradient-crushed sequences. The MRF ssEPG T(2) estimates over 0 < T(2) < 100 ms improve accuracy by > 10 ms at some values, relative to other modeling approaches. Small deviations in B(0) can produce substantial bias in T(2) estimations from a range of MRF sequence types, and these effects can be modeled and understood by ssEPG. CONCLUSION: Transient-state, gradient-crushed sequences such as those used in MRF are sensitive to slice profile effects, and these effects depend on RF pulse choice, gradient crusher strength, and ΔB(0). It was found ssEPG was the most accurate EPG-based means to model these effects.

PURPOSE: Propose a novel decomposition based model employing the total generalized variation (TGV) and the nuclear norm, which can be used in compressed sensing based dynamic MR reconstructions. THEORY AND METHODS: We employ the nuclear norm to represent the time-coherent background and the spatio-temporal TGV functional for the sparse dynamic component above. We first discuss the existence of solutions to the proposed model, and then design an algorithm using the classical first-order Primal-Dual method for solving the proposed model and give the norm estimation for the convergence condition. The proposed model is compared with the state-of-the-art methods on different datasets under different sampling schemes and acceleration factors. RESULTS: The proposed model achieves higher SERs and SSIMs than kt-SLR, kt-RPCA, L+S and ICTGV on cardiac cine, perfusion and breast DCE-MRI datasets under both pseudo radial and Cartesian sampling schemes. In addition, the proposed model better suppresses the spatial artifacts and preserves the edges. CONCLUSION: The proposed model outperforms the state-of-the-art methods and generates high quality reconstructions under different sampling schemes and different acceleration factors.

Purpose. Dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) is used in cancer imaging to probe tumor vascular properties. Compressed sensing (CS) theory makes it possible to recover MR images from randomly undersampled k-space data using nonlinear recovery schemes. The purpose of this paper is to quantitatively evaluate common temporal sparsity-promoting regularizers for CS DCE-MRI of the breast. Methods. We considered five ubiquitous temporal regularizers on 4.5x retrospectively undersampled Cartesian in vivo breast DCE-MRI data: Fourier transform (FT), Haar wavelet transform (WT), total variation (TV), second-order total generalized variation (TGVα2), and nuclear norm (NN). We measured the signal-to-error ratio (SER) of the reconstructed images, the error in tumor mean, and concordance correlation coefficients (CCCs) of the derived pharmacokinetic parameters Ktrans (volume transfer constant) and ve (extravascular-extracellular volume fraction) across a population of random sampling schemes. Results. NN produced the lowest image error (SER: 29.1), while TV/TGVα2 produced the most accurate Ktrans (CCC: 0.974/0.974) and ve (CCC: 0.916/0.917). WT produced the highest image error (SER: 21.8), while FT produced the least accurate Ktrans (CCC: 0.842) and ve (CCC: 0.799). Conclusion. TV/TGVα2 should be used as temporal constraints for CS DCE-MRI of the breast.

A novel anthropomorphic flow phantom device has been developed, which can be used for quantitatively assessing the ability of magnetic resonance imaging (MRI) scanners to accurately measure signal/concentration time-intensity curves (CTCs) associated with dynamic contrast-enhanced (DCE) MRI. Modelling of the complex pharmacokinetics of contrast agents as they perfuse through the tumour capillary network has shown great promise for cancer diagnosis and therapy monitoring. However, clinical adoption has been hindered by methodological problems, resulting in a lack of consensus regarding the most appropriate acquisition and modelling methodology to use and a consequent wide discrepancy in published data. A heretofore overlooked source of such discrepancy may arise from measurement errors of tumour CTCs deriving from the imaging pulse sequence itself, while the effects on the fidelity of CTC measurement of using rapidly-accelerated sequences such as parallel imaging and compressed sensing remain unknown. The present work aimed to investigate these features by developing a test device in which 'ground truth' CTCs were generated and presented to the MRI scanner for measurement, thereby allowing for an assessment of the DCE-MRI protocol to accurately measure this curve shape. The device comprised a four-pump flow system wherein CTCs derived from prior patient prostate data were produced in measurement chambers placed within the imaged volume. The ground truth was determined as the mean of repeat measurements using an MRI-independent, custom-built optical imaging system. In DCE-MRI experiments, significant discrepancies between the ground truth and measured CTCs were found for both tumorous and healthy tissue-mimicking curve shapes. Pharmacokinetic modelling revealed errors in measured K trans, v e and k ep values of up to 42%, 31%, and 50% respectively, following a simple variation of the parallel imaging factor and number of signal averages in the acquisition protocol. The device allows for the quantitative assessment and standardisation of DCE-MRI protocols (both existing and emerging).