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Abstract The possibility of modifying the ferromagnetic response of a multiferroic heterostructure via fully optical means exploiting the photovoltaic/photostrictive properties of the ferroelectric component is an effective method for tuning the interfacial properties. In this study, the effects of 405 nm visible‐light illumination on the ferroelectric and ferromagnetic responses of (001) Pb(Mg1/3Nb2/3)O3‐0.4PbTiO3 (PMN‐PT)/Ni heterostructures are presented. By combining electrical, structural, magnetic, and spectroscopic measurements, how light illumination above the ferroelectric bandgap energy induces a photovoltaic current and the photostrictive effect reduces the coercive field of the interfacial magnetostrictive Ni layer are shown. Firstly, a light‐induced variation in the Ni orbital moment as a result of sum‐rule analysis of x‐ray magnetic circular dichroic measurements is reported. The reduction of orbital moment reveals a photogenerated strain field. The observed effect is strongly reduced when polarizing out‐of‐plane the PMN‐PT substrate, showing a highly anisotropic photostrictive contribution from the in‐plane ferroelectric domains. These results shed light on the delicate energy balance that leads to sizeable light‐induced effects in multiferroic heterostructures, while confirming the need of spectroscopy for identifying the physical origin of interface behavior.

Abstract Background Fall armyworm, Spodoptera frugiperda, an alien invasive pest from the Americas, was detected in Zambia late 2016 and since has caused significant losses on maize threatening livelihood and food security. Individually, farmers continue to rely on synthetic pesticides, a reactive measure to manage new invasive insect pests, posing risks to human health, the environment and biodiversity. Biological control has been proven to be an efficient, cost effective and safe method for pest and disease management, and when adopted collectively, its effectiveness can increase. In addition, collective action has been acknowledged to be a critical component for invasive species management, but is still poorly studied in low- and middle-income countries (LMIC) where the national plant health system, in-place to prevent and manage biological invasions, is limited. Methods To study the feasibility of creating a collective action to promote biological control for fall armyworm among smallholder farmers in rural Zambia and the social and institutional conditions needed for it to be successful and sustainable, we conducted focus group discussions and in-depth interviews in two districts with maize smallholder farmers. Our model to assess the results applies both Ostrom’s 8 Design Principles for a community-based management of common-pool resources and criteria of an agricultural innovation that meet the community’s requirements, and also pays attention to the exchange and brokering processes needed to match the two. Results Our results showed that some conditions are already in place to support a collective action to manage fall armyworm such as matching rules to local conditions, collective-choice arrangement, conflict-resolution mechanism and minimal recognition of rights to organize which are supported by traditional leadership of the communities. However other conditions would need to be strengthened for the collective pest management to be sustainable. The most important criteria for a pest management innovation selected by participants from both districts, in no specific order, were price, efficacy, recommended by agrodealer/extension officer and immediate action. Conclusions This study fills a gap in understanding social and institutional conditions in LMIC needed to sustain a collective action that aim at controlling a highly mobile and invasive pest. Our study emphasizes the need to redefine technologies and dissemination in terms of supporting the processes of co-designing innovation based on social and ecological conditions.

Thin-slices multi-detector computed tomography (MDCT) plays a key role in the differential diagnosis of interstitial lung disease (ILD). However, thin-slices MDCT has a limited ability to detect active inflammation, which is an important target of newly developed ILD drug therapy. Magnetic resonance imaging (MRI), thanks to its multi-parameter capability, provides better tissue characterisation than thin-slices MDCT. Our aim was to summarise the current status of MRI applications in ILD and to propose an ILD-MRI protocol. A systematic literature search was conducted for relevant studies on chest MRI in patients with ILD. We retrieved 1246 papers of which 55 original papers were selected for the review. We identified 24 studies comparing image quality of thin-slices MDCT and MRI using several MRI sequences. These studies described new MRI sequences to assess ILD parenchymal abnormalities, such as honeycombing, reticulation and ground-glass opacity. Thin-slices MDCT remains superior to MRI for morphological imaging. However, recent studies with ultra-short echo-time MRI showed image quality comparable to thin-slices MDCT. Several studies demonstrated the added value of chest MRI by using functional imaging, especially to detect and quantify inflammatory changes. We concluded that chest MRI could play a role in ILD patients to differentiate inflammatory and fibrotic changes and to assess efficacy of new ILD drugs.