Magnetic field coupling with lunar soil simulants.

Wireless power transfer (WPT) using magnetically coupled resonators is being integrated into space vehicles destined for the lunar surface. The dusty soil on the Moon, called lunar regolith, is known to adhere to surfaces and is also known to contain iron, including iron oxides and metallic iron. Regolith samples are limited, and lunar soil simulants are commonly used in space science research for efforts in surface vehicle navigation, in-situ resource utilization, and power infrastructure. However, most simulants contain no metallic iron, and research involving electromagnetic field interactions with regolith would benefit from incorporating metallic iron into test samples. This work presents experimental results from tests using WPT with magnetically coupled resonators in the presence of various standard lunar simulants, plus a new iron-enriched simulant and metallic iron powders. Results for power transfer efficiency, thermal response, and frequency response are presented and demonstrate that the presence of metallic iron and its particle size are critical factors affecting the coupling of the incident magnetic field with lunar simulants and iron powder samples. The importance of particle size-to-skin depth ratio is discussed. Attenuation constants for various iron powders are estimated from experimental data and compared to those of lunar regolith and simulants.

Characterization of the impact of the MYBBP1A gene and rs3809849 on asparaginase sensitivity and cellular functions.

Aims: To investigate the role of MYBBP1A gene and rs3809849 in pancreatic cancer (PANC1) and lymphoblastic leukemia (NALM6) cell lines and their response to asparaginase treatment. Materials & methods: The authors applied CRISPR-Cas9 to produce MYBBP1A knock-out (KO) and rs3809849 knock-in (KI) cell lines. The authors also interrogated rs3809849's impact on PANC1 cells through allele-specific overexpression. Results: PANC1 MYBBP1A KO cells exhibited lower proliferation capacity (p ≤ 0.05), higher asparaginase sensitivity (p = 0.01), reduced colony-forming potential (p = 0.001), cell cycle blockage in S phase, induction of apoptosis and remarkable morphology changes suggestive of an epithelial-mesenchymal transition. Overexpression of the wild-type (but not the mutant) allele of MYBBP1A-rs3809849 in PANC1 cells increased asparaginase sensitivity. NALM6 MYBBP1A KO displayed resistance to asparaginase (p < 0.0001), whereas no effect for rs3809849 KI was noted. Conclusions:MYBBP1A is important for regulating various cellular functions, and it plays, along with its rs3809849 polymorphism, a tissue-specific role in asparaginase treatment response.

Multi-scale approach to biodiversity proxies of biological control service in European farmlands.

Intensive agriculture has profoundly altered biodiversity and trophic relationships in agricultural landscapes, leading to the deterioration of many ecosystem services such as pollination or biological control. Information on which spatio-temporal factors are simultaneously affecting crop pests and their natural enemies is required to improve conservation biological control practices. We conducted a study in 80 winter wheat crop fields distributed in three regions of North-western Europe (Brittany, Hauts-de-France and Wallonia), along intra-regional gradients of landscape complexity. Five taxa of major crop pests (aphids and slugs) and natural enemies (spiders, carabids, and parasitoids) were sampled three times a year, for two consecutive years. We analysed the influence of regional (meteorology), landscape (structure in both the years n and n-1) and local factors (hedge or grass strip field boundaries, and distance to boundary) on the abundance and species richness of crop-dwelling organisms, as proxies of the service/disservice they provide. Firstly, there was higher biocontrol potential in areas with mild winter climatic conditions. Secondly, natural enemy communities were less diverse and had lower abundances in landscapes with high crop and wooded continuities (sum of interconnected crop or wood surfaces), contrary to slugs and aphids. Finally, field boundaries with grass strips were more favourable to spiders and carabids than boundaries formed by hedges, while the opposite was found for crop pests, with the latter being less abundant towards the centre of the fields. We also revealed temporal modulation-and sometimes reversion-of the impact of local elements on crop biodiversity. To some extent, these results cause controversy because they show that hedgerows and woodlots should not be the unique cornerstones of agro-ecological landscape design strategies. We point out that combining woody and grassy habitats to take full advantage of the features and ecosystem services they both provide (biological pest control, windbreak effect, soil stabilization) may promote sustainable agricultural ecosystems. It may be possible to both reduce pest pressure and promote natural enemies by accounting for taxa-specific antagonistic responses to multi-scale environmental characteristics.

Impact of Air Transport on SpO2/FiO2 among Critical COVID-19 Patients during the First Pandemic Wave in France.

During the first wave of the COVID-19 pandemic, some French regions were more affected than others. To relieve those areas most affected, the French government organized transfers of critical patients, notably by plane or helicopter. Our objective was to investigate the impact of such transfers on the pulse oximetric saturation (SpO2)-to-inspired fraction of oxygen (FiO2) ratio among transferred critical patients with COVID-19. We conducted a retrospective study on medical and paramedical records. The primary endpoint was the change in SpO2/FiO2 during transfers. Thirty-eight patients were transferred between 28 March and 5 April 2020, with a mean age of 62.4 years and a mean body mass index of 29.8 kg/m2. The population was 69.7% male, and the leading medical history was hypertension (42.1%), diabetes (34.2%), and dyslipidemia (18.4%). Of 28 patients with full data, we found a decrease of 28.9 points in SpO2/FiO2 (95% confidence interval, 5.8 to 52.1, p = 0.01) between the starting and the arrival intensive care units (SpO2/FiO2, 187.3 ± 61.3 and 158.4 ± 62.8 mmHg, respectively). Air medical transfers organized to relieve intensive care unit teams under surging conditions during the first COVID wave were associated with significant decreases in arterial oxygenation.

Stress among Emergency Health Care Workers on Nuclear or Radiation Disaster: A Preliminary State Survey.

BACKGROUND: The nuclear or radiation disaster risk within the French Auvergne-Rhone-Alpes state is low (but not absent) due to its proximity to four Nuclear Power Generation Centers and two regional cancer control centers. This study aims to compare subjective stress ratings for emergency health care workers regarding nuclear and radiation disasters between two locations: at work versus at home. MATERIALS AND METHODS: We distributed an anonymous online questionnaire via RedCap® to all emergency health care workers who could be involved in patient care after a nuclear or radiation disaster. It comprised 18 questions divided into three parts-theoretical knowledge and practical assessment, stress assessment, and sociodemographic criteria. RESULTS: We analyzed 107 responses. There was a significant 11-point increase in stress levels between work and home regarding nuclear or radiation disaster risks (p = 0.01). Less than 25% of emergency health care workers surveyed benefited from annual training. CONCLUSION: The stress levels of emergency health care workers regarding nuclear or radiation disaster were higher at work than at home and increased without annual training. It is important to increase knowledge about these protocols and to mandate yearly training for all workers potentially involved in these disasters.

Response of life-history traits to artificial and natural selection for virulence and nonvirulence in a Drosophila parastitoid, Asobara tabida.

Co-evolution of host-parasitoid interactions is determined by the costs of host resistance, which received empirical evidence, and the costs of parasitoid virulence, which have been mostly hypothesized. Asobara tabida is a parasitoid, which mainly parasitizes Drosophila melanogaster and D. subobscura, the first species being able to resist to the parasitoid development while the second species is not. To parasitize resistant hosts, including D. melanogaster, A. tabida develops sticky eggs, which prevent encapsulation, but this virulence mechanism may be costly. Interindividual and interpopulation variation in the proportion of sticky eggs respectively allowed us to (i) artificially select and compare life-history traits of a virulent and a nonvirulent laboratory strain, and (ii) compare a virulent and a nonvirulent field strain, to investigate the hypothetical costs of virulence. We observed strong differences between the 2 laboratory strains. The nonvirulent strain invested fewer resources in reproduction and walked less than the virulent one but lived longer. Concerning the field strains, we observed that the nonvirulent strain had larger wings while the virulent one walked more and faster. All together, our results suggest that virulence may not always be costly, but rather that different life histories associated with different levels of virulence may coexist at both intra- and interpopulation levels.

The Wide Potential Trophic Niche of the Asiatic Fruit Fly Drosophila suzukii: The Key of Its Invasion Success in Temperate Europe?

The Asiatic fruit fly Drosophila suzukii has recently invaded Europe and North and South America, causing severe damage to fruit production systems. Although agronomic host plants of that fly are now well documented, little is known about the suitability of wild and ornamental hosts in its exotic area. In order to study the potential trophic niche of D. suzukii with relation to fruit characteristics, fleshy fruits from 67 plant species were sampled in natural and anthropic ecosystems (forests, hedgerows, grasslands, coastal areas, gardens and urban areas) of the north of France and submitted to experimental infestations. A set of fruit traits (structure, colour, shape, skin texture, diameter and weight, phenology) potentially interacting with oviposition choices and development success of D. suzukii was measured. Almost half of the tested plant species belonging to 17 plant families allowed the full development of D. suzukii. This suggests that the extreme polyphagy of the fly and the very large reservoir of hosts producing fruits all year round ensure temporal continuity in resource availability and contribute to the persistence and the exceptional invasion success of D. suzukii in natural habitats and neighbouring cultivated systems. Nevertheless, this very plastic trophic niche is not systematically beneficial to the fly. Some of the tested plants attractive to D. suzukii gravid females stimulate oviposition but do not allow full larval development. Planted near sensitive crops, these "trap plants" may attract and lure D. suzukii, therefore contributing to the control of the invasive fly.

Aphid Parasitoid Mothers Don't Always Know Best through the Whole Host Selection Process.

Parasitoid host selection behaviour has been extensively studied in experimentally simplified tritrophic systems formed by one single food chain (one plant, one herbivore and one parasitoid species). The "Mother knows best" hypothesis predicts that the preference for a plant-host complex should be positively correlated with plant quality for offspring performance. We studied the host selection behaviour of the generalist endoparasitoid Aphidius matricariae towards the black bean aphid Aphis fabae in the intercrop system including Vicia faba as a focal plant and its companion plant Camelina sativa. Dual-choice laboratory bioassays revealed that parasitoid females preferred to orientate towards (1) the plant-aphid complex over the non-infested plant whatever the complex (2) the C. sativa-A. fabae complex over the V. faba-A. fabae complex. In dual choice attack rate bioassays, parasitoid females showed more interest towards the aphids on C. sativa but paradoxically chose to oviposit more in aphids on V. faba. Ultimately, parasitoids that had developed on the V. faba-A. fabae complex exhibited better fitness parameters. By demonstrating that parasitoid females were able to discriminate the aphid host that offered the highest fitness to their offspring but selected beforehand the least suitable plant-aphid complex, we provide key insight into the disruption in their host selection behaviour potentially triggered by diverse habitats. This suggests that the "Mother knows best" hypothesis could be thwarted by increasing the complexity of the studied systems.

Optical design and multi-length-scale scanning spectro-microscopy possibilities at the Nanoscopium beamline of Synchrotron Soleil.

The Nanoscopium 155 m-long beamline of Synchrotron Soleil is dedicated to scanning hard X-ray nanoprobe techniques. Nanoscopium aims to reach ≤100 nm resolution in the 5-20 keV energy range for routine user experiments. The beamline design tackles the tight stability requirements of such a scanning nanoprobe by creating an overfilled secondary source, implementing all horizontally reflecting main beamline optics, applying high mechanical stability equipment and constructing a dedicated high-stability building envelope. Multi-technique scanning imaging and tomography including X-ray fluorescence spectrometry and spectro-microscopy, absorption, differential phase and dark-field contrasts are implemented at the beamline in order to provide simultaneous information on the elemental distribution, speciation and sample morphology. This paper describes the optical concept and the first measured performance of the Nanoscopium beamline followed by the hierarchical length-scale multi-technique imaging experiments performed with dwell times down to 3 ms per pixel.

Wild Solanum resistance to aphids: antixenosis or antibiosis?

The type (antixenosis or antibiosis) of resistance against the aphids Myzus persicae (Sulzer) and Macrosiphum euphorbiae (Thomas) was characterized for the wild tuber-bearing potatoes, Solanum chomatophilum Bitter and Solanum stoloniferum Schltdl. & Bouché through behavioral (olfactometry and electrical penetration graph) and physiological studies. In dual-choice assays, only S. stoloniferum exerted attraction to M. euphorbiae. This ruled out the possibility that plant volatiles of S. chomatophilum and S. stoloniferum may contribute to the high resistance expressed. In electrical penetration graph experiments, aphids feeding on S. stoloniferum showed increased salivation phases, whereas phloem ingestion was drastically reduced for both aphid species. Because reaching phloem elements was not delayed in both species, the resistance mechanism was phloem-located. The antixenosis exhibited by S. stoloniferum was similar on young and mature leaves. S. chomatophilum also showed phloem-located antixenosis against M. persicae. In contrast, M. euphorbiae had no difficulty to reach S. chomatophilum phloem tissues and to ingest sap. S. chomatophilum resistance against M. euphorbiae was antibiosis and only expressed in mature leaves, where a complete nymphal mortality was observed.

Rapid method to screen resistance of potato plants against Myzus persicae (Homoptera: Aphididae) in the laboratory.

With the objective to develop a potato, Solanum tuberosum L., resistance program against aphids, we propose a rapid screening method with Myzus persicae (Sulzer) in the laboratory. We aimed to optimize the duration of the whole procedure and to decrease the frequency of measurements. In a first experiment, intrinsic rate of natural increase (r(m)) values were compared between adult aphids reared throughout their entire life and adults reared only during a period equivalent to their prereproductive period. No significant differences were observed. In a second experiment, four groups of aphids were distinguished according to the sampling frequency, i.e., those whose biological parameters were evaluated every single, second, third, and fourth day. Except for the fourth-day experiment, the r(m) values estimated on aphids reared on the three potato lines were not significantly different whatever sampling frequency of single, second, or third day used to check aphids. Thus, screening efforts in laboratory can be largely optimized by evaluating adult aphids only during a period equivalent to their prereproductive period and assessing M. persicae populations every third day. Our method is reliable and adapted to screen a large number of potato plants against M. persicae because it allows an average 70% reduction in the time required for the whole experimental process.