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This article pulls together the state of knowledge on the degree to which wheat-based systems in Bangladesh, India, Nepal, and Pakistan, are feminizing. It is not yet possible to make definitive statements. However, it is clear that wheat-based systems are undergoing far-reaching changes in relation to “who does what” and “who decides.” There are some commonalities across all four countries. Intersectionalities shape women’s identities and abilities to exert their agency. Purdah is a cultural norm in many locations. Nevertheless, each country displays different meta-trends. In Nepal managerial feminization is increasing unlike in Pakistan. Women in Bangladesh spend the least time in field work whereas in other countries they are often strongly engaged. There are strong local variations within countries as well which we explore. Establishing the extent of feminization is challenging because studies ask different questions, operate at different levels, and are rarely longitudinal. Researchers often construct men as primary farmers, leading to a failure to find out what men and women really do and decide. This diminishes the value of many studies. Cultural perceptions of honor can make men respondents reluctant to report on women’s agency and women can be reluctant to claim agency openly. We provide suggestions for better research, and urge support to women as workers and decision-makers.

The importance of gender norms in agricultural innovation processes has been recognized. However, the operational integration of these normative issues into the innovation strategies of agricultural interventions remains challenging. This article advances a replicable, integrative research approach that captures key local conditions to inform the design and targeting of gender-inclusive interventions. We focus on the gender climate across multiple contexts to add to the limited indicators available for assessing gender norms at scale. The notion of gender climate refers to the socially constituted rules that prescribe men's and women's behaviour in a specific geographic location-with some being more restrictive and others more relaxed. We examine the gender climate of 70 villages across 13 countries where agriculture is an important livelihood. Based on data from the GENNOVATE initiative we use multivariate methods to identify three principal components: 'Gender Climate', 'Opportunity' and 'Connectivity'. Pairwise correlation and variance partitioning analyses investigate the linkages between components. Our findings evidence that favourable economic or infrastructure conditions do not necessarily correlate with favourable gender normative conditions. Drawing from two case-study villages from Nepal, we highlight opportunities for agricultural research for development interventions. Overall, our approach allows to integrate local knowledge about gender norms and other local conditions into the planning and targeting strategies for agricultural innovation.

The study of shock-driven ejecta production has focused on Richtmyer–Meshkov instability (RMI) growth from geometric features of the material surface. Extensive study of this mechanism under both single- and multiple-shock conditions has found that the ejected mass tends to be closely associated with the shocked surface phase, and its temperature is not dramatically greater than the hydrodynamic shock temperature of the bulk. In this work, we propose and demonstrate a new ejecta production mechanism that can occur under multiple-shock conditions based on the collapse of bubbles near the free surface of the material. This mechanism produces ejected mass that is much greater in quantity than observed in the RMI case. The particles are much hotter than predicted by the shock Hugoniot state, and the ejected mass does not appear to be strongly dependent upon initial surface finish. The ejecta source extends into the material with no clear remaining free surface. We name this mechanism Shallow Bubble Collapse (SBC) and discuss the conditions under which it activates. We demonstrate resolved modeling methods that enable the calculation, design, and study of SBC as a mechanism and perform a series of experiments to compare with the models. Under some multiple-shock conditions, SBC ejection produces ten times more ejected mass than RMI growth. [ABSTRACT FROM AUTHOR]

Hip dysplasia (HD) is a frequent cause of hip pain in skeletally mature patients and may lead to osteoarthritis (OA). An accurate and early diagnosis may postpone, reduce or even prevent the onset of OA and ultimately hip arthroplasty at a young age. The overall aim of this study was to assess the reliability of an algorithm, designed to read pelvic anterior-posterior (AP) radiographs and to estimate the agreement between the algorithm and human readers for measuring (i) lateral center edge angle of Wiberg (LCEA) and (ii) Acetabular index angle (AIA). The algorithm was based on deep-learning models developed using a modified U-net architecture and ResNet 34. The newly developed algorithm was found to be highly reliable when identifying the anatomical landmarks used for measuring LCEA and AIA in pelvic radiographs, thus offering highly consistent measurement outputs. The study showed that manual identification of the same landmarks made by five specialist readers were subject to variance and the level of agreement between the algorithm and human readers was consequently poor with mean measured differences from 0.37 to 9.56° for right LCEA measurements. The algorithm displayed the highest agreement with the senior orthopedic surgeon. With further development, the algorithm may be a good alternative to humans when screening for HD.

In this work, we measure continuous thermal radiance from evolving clouds of liquid metal fragments ejected into vacuum, nonreactive, and reactive gas. We implement a model for the thermalization of the ejecta and gas and use this to constrain the absolute temperature of the ejecta cloud. This model enables further analyses of ejecta thermal behavior under a variety of conditions. [ABSTRACT FROM AUTHOR]

In chronic lymphocytic leukemia, TP53 mutations and deletion of chromosome 17p are well-characterized biomarkers associated with poor progression-free and overall survival following chemoimmunotherapy. Patients harboring low burden TP53 mutations with variant allele frequencies of 0.3-15% have been shown to have similar dismal outcome as those with high burden mutations. We here describe a highly sensitive deep targeted next-generation sequencing assay allowing for the detection of TP53 mutations as low as 0.2% variant allele frequency. Within a consecutive, single center cohort of 290 newly diagnosed patients with chronic lymphocytic leukemia, deletion of chromosome 17p was the only TP53 aberration significantly associated with shorter overall survival and treatment-free survival. We were unable to demonstrate any impact of TP53 mutations, whether high burden (variant allele frequency >10%) or low burden (variant allele frequency ≤10%), in the absence of deletion of chromosome 17p. In addition, the impact of high burden TP53 aberration (deletion of chromosome 17p and/or TP53 mutation with variant allele frequency >10%) was only evident for patients with IGHV unmutated status; no impact of TP53 aberrations on outcome was seen for patients with IGHV mutated status. In 61 patients at time of treatment, the prognostic impact of TP53 mutations over 1% variant allele frequency could be confirmed. This study furthers the identification of a clinical significant limit of detection for robust TP53 mutation analysis in chronic lymphocytic leukemia. Multicenter studies are needed for validation of ultra-sensitive TP53 mutation assays in order to define and implement a technical as well as a clinical lower limit of detection.

Shock temperature, stress, and dynamic emissivity for cerium shocked from 8.4 to 23.5 GPa were measured. In addition, the isentropic shock release temperature as a function of release stress was determined at a window interface. Cerium samples were shock compressed by plate impact on a single-stage gun. We made time-resolved measurements of thermal radiance, reflectance, and interface velocity of samples glued to lithium fluoride windows. Reflectance was measured with an integrating sphere and velocity with photonic Doppler velocimetry. From these measurements, we determined the temperature, emissivity, and stress at the interface. For shock stresses below 10.24 GPa, the samples were shocked from the γ phase into the α phase; at higher stresses, the cerium presumably melted or entered a mixed phase upon shock. The shock Hugoniot temperature as a function of stress follows a straight line over the entire range of our measurements, disagreeing with previously published predictions that the Hugoniot would follow the melt boundary from 10.24 up to around 16–18 GPa. Between 11.9 and 16.8 GPa, all the release isentropes converged (within experimental uncertainty) to a point around 4 GPa and 900 K, near the published melt curve. For experiments shocked above ∼16 GPa, the release isentropes behave differently. This suggests that within this 12–16 GPa range, there is a phase transition taking place, probably melt, and that it is occurring somewhere along the shock and release path. We could not identify a single-valued phase boundary from our experiments. Potential reasons for this are discussed. [ABSTRACT FROM AUTHOR]

We studied the collapse of individual helium gas bubbles in the homogeneous explosive nitromethane (NM) to investigate effects of hot-spot formation on the detonation process. A bubble was injected into a NM sample, and a shock wave from an explosive detonator compressed the bubble, creating a localized hot spot. We measured shock and detonation wave speeds with optical velocimetry, and we used a high-speed camera to image the shock propagation and the pre- and post-bubble collapse processes. An infrared camera image showed the residual radiance temperature distribution after the bubble collapse, and an optical fiber pyrometer measured the time-resolved thermal radiance. We measured the optical spectra of light emitted from detonating NM without a bubble and from a collapsing bubble in shocked, undetonated NM. We estimated temperatures of the detonation fronts and of the hot spots formed by bubble collapse. To study the incipient detonation process, we performed all bubble collapse experiments at pressures below the threshold for creating a sustained detonation. Where the bubble collapsed, we observed an opaque, thermally emissive region believed to be chemical reaction products. Chemical reactions in NM can be produced with lower shock pressures (∼1 GPa) when a helium bubble is present than without a bubble (∼10 GPa). We used hydrodynamic modeling to predict shock wave propagation, extent of chemical reaction, and subsequent temperature rise from the collapsing bubble. Simulations using a temperature-dependent Arrhenius burn model gave much better results than reactive burn models that depend only on pressure and density. [ABSTRACT FROM AUTHOR]

Temperature is a difficult thermodynamic variable to measure in dynamic compression experiments. Optical pyrometry is a general-purpose technique for measuring temperature from a radiant surface, but that surface is often the interface between distinct materials with temperatures that vary spatially along the loading direction. This leads to a fundamental problem: how does the measured interface temperature relate to this temperature profile along the compression axis? Numerical analysis of loading history and thermal diffusion at these interfaces shows that seemingly subtle changes in experiment geometry can lead to very different temperature profiles. We compare these results to laboratory temperature measurements of shock-compressed tin. [ABSTRACT FROM AUTHOR]

We have developed a new technique to measure the melt curve of a shocked metal sample and have used it to measure the high-pressure solid-liquid phase boundary of tin from 10 to 30 GPa and 1000 to 1800 K. Tin was shock compressed by plate impact using a single-stage powder gun, and we made accurate, time-resolved radiance, reflectance, and velocimetry measurements at the interface of the tin sample and a lithium fluoride window. From these measurements, we determined temperature and pressure at the interface vs time. We then converted these data to temperature vs pressure curves and plotted them on the tin phase diagram. The tin sample was initially shocked into the high-pressure solid γ phase, and a subsequent release wave originating from the back of the impactor lowered the pressure at the interface along a constant entropy path (release isentrope). When the release isentrope reaches the solid-liquid phase boundary, melt begins and the isentrope follows the phase boundary to low pressure. The onset of melt is identified by a significant change in the slope of the temperature-pressure release isentrope. Following the onset of melt, we obtain a continuous and highly accurate melt curve measurement. The technique allows a measurement along the melt curve with a single radiance and reflectance experiment. The measured temperature data are compared to the published equation of state calculations. Our data agree well with some but not all of the published melt curve calculations, demonstrating that this technique has sufficient accuracy to assess the validity of a given equation of state model. [ABSTRACT FROM AUTHOR]

We fielded experiments to compare temperatures measured simultaneously by pyrometry and Raman spectroscopy in toluene shocked to 9 GPa. A 0.5 mm thick toluene sample was compressed between sapphire windows by plate impact from a gas gun. As the shock wave reverberated between the windows, the pressure increased stepwise to about 9 GPa. While the sample was near its peak pressure, we measured the Raman spectrum and determined temperature from the ratio of the Stokes and anti-Stokes intensities. Simultaneously, we measured the sample thermal radiance from the C-H vibration bands that occur between 3.2 and 3.6 μm to determine temperature pyrometrically. The pyrometer used a biased indium antimonide detector paired with a custom transimpedance amplifier, a system capable of temperature measurements as low as about 400 K. The Raman measurements gave a temperature of 530 ± 25 K in the bulk volume of toluene. Pyrometry gave a temperature of 496 + 15/−20 K, which is in reasonable agreement with the Raman measurement. Comparisons of this type are necessary to validate pyrometry as a temperature diagnostic in dynamic experiments. [ABSTRACT FROM AUTHOR]