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Growing interest in quantum computing for practical applications has led to a surge in the availability of programmable machines for executing quantum algorithms 1 , 2 . Present-day photonic quantum computers 3 – 7 have been limited either to non-deterministic operation, low photon numbers and rates, or fixed random gate sequences. Here we introduce a full-stack hardware−software system for executing many-photon quantum circuit operations using integrated nanophotonics: a programmable chip, operating at room temperature and interfaced with a fully automated control system. The system enables remote users to execute quantum algorithms that require up to eight modes of strongly squeezed vacuum initialized as two-mode squeezed states in single temporal modes, a fully general and programmable four-mode interferometer, and photon number-resolving readout on all outputs. Detection of multi-photon events with photon numbers and rates exceeding any previous programmable quantum optical demonstration is made possible by strong squeezing and high sampling rates. We verify the non-classicality of the device output, and use the platform to carry out proof-of-principle demonstrations of three quantum algorithms: Gaussian boson sampling, molecular vibronic spectra and graph similarity 8 . These demonstrations validate the platform as a launchpad for scaling photonic technologies for quantum information processing. A system for realizing many-photon quantum circuits is presented, comprising a programmable nanophotonic chip operating at room temperature, interfaced with a fully automated control system.

Lightning discharges between charged clouds and the Earth’s surface are responsible for considerable damages and casualties. It is therefore important to develop better protection methods in addition to the traditional Franklin rod. Here we present the first demonstration that laser-induced filaments—formed in the sky by short and intense laser pulses—can guide lightning discharges over considerable distances. We believe that this experimental breakthrough will lead to progress in lightning protection and lightning physics. An experimental campaign was conducted on the Säntis mountain in north-eastern Switzerland during the summer of 2021 with a high-repetition-rate terawatt laser. The guiding of an upward negative lightning leader over a distance of 50 m was recorded by two separate high-speed cameras. The guiding of negative lightning leaders by laser filaments was corroborated in three other instances by very-high-frequency interferometric measurements, and the number of X-ray bursts detected during guided lightning events greatly increased. Although this research field has been very active for more than 20 years, this is the first field-result that experimentally demonstrates lightning guided by lasers. This work paves the way for new atmospheric applications of ultrashort lasers and represents an important step forward in the development of a laser based lightning protection for airports, launchpads or large infrastructures.A terawatt laser filament is shown to be able to guide lightning over a distance of 50 m in field trials on the Säntis mountain in the Swiss Alps.

To address the issue that liquid rocket launch pad performance metrics fail to meet national space development requirements and constrain the enhancement of space launch capabilities, an evaluation index system for launch pad effectiveness has been established. Employing the Analytic Hierarchy Process (AHP) and Multi-Attribute Decision-Making (MADM) methodology, a multi-attribute performance evaluation model for launch pads was constructed. Based on this model, a comprehensive assessment of a specific launch pad’s performance was conducted. Recommendations for enhancing the launch pad’s performance were formulated based on the evaluation and analysis results. This validated the rationality of the multi-attribute performance evaluation model for launch pads, providing a reference basis for the design, operation, and improvement of launch facilities.

Background: The effectiveness of dietetic consultations is measured by clinical and nutritional outcomes. However, for change to occur, patients need to be able to apply any dietary advice offered. Previous research has failed to explain how, why, when and for whom dietetic consultations work. We used realist methodology to uncover the hidden, causal mechanisms that help to explain dietetic consultation outcomes. Research Objective: To understand the architecture of the dietetic consultation. Methods: A review team of academic dietitians brainstormed an initial programme theory. Eleven electronic databases were searched using terms relating to the experience of the dietetic consultation and patient-centred dietetic care. Eligible articles were assessed for inclusion by two reviewers. Data were extracted using an iterative, programme theory-driven approach, refined until no new theory statements could be constructed. Context-Mechanism-Outcome configurations and a final programme theory were derived according to realist principles. Results: Thirty-seven publications were included in the final synthesis. Findings suggest that the success of the dietetic consultation occurs through the synergistic interdependence of three spheres of influence: the patient-dietitian relationship, dietitian skill, and the dietetic service. In a dynamic and complex interchange, a variety of contextual factors such as inter-professional allyship and cultural competence interacted with the mechanism resources offered such as adaptable service delivery and tailoring skills to impact dietetic consultation outcomes, through various mechanism responses, including improved collaboration and patient empowerment, among others. Discussion: This novel approach to conceptualising the dietetic consultation uncovered previously-unknown generative mechanisms. A complex interaction of contexts, mechanisms and outcomes in an interactive, multi-layered construct adds explanatory value to previous literature on patient-centred care in dietetic practice. This study deepens our understanding of how dietetic consultations work, for whom, and under what circumstances, and provides a launchpad for innovation in practice, research and education.

The Emirates Mars Mission (EMM) was launched to Mars in the summer of 2020, and is the first interplanetary spacecraft mission undertaken by the United Arab Emirates (UAE). The mission has multiple programmatic and scientific objectives, including the return of scientifically useful information about Mars. Three science instruments on the mission’s Hope Probe will make global remote sensing measurements of the Martian atmosphere from a large low-inclination orbit that will advance our understanding of atmospheric variability on daily and seasonal timescales, as well as vertical atmospheric transport and escape. The mission was conceived and developed rapidly starting in 2014, and had aggressive schedule and cost constraints that drove the design and implementation of a new spacecraft bus. A team of Emirati and American engineers worked across two continents to complete a fully functional and tested spacecraft and bring it to the launchpad in the middle of a global pandemic. EMM is being operated from the UAE and the United States (U.S.), and will make its data freely available.

Mars Express was conceived and built by ESA as a successor of the unsuccessful Russian Mars-96 mission. It was planned from the onset as an orbiter and lander mission to be able to carry out long-term, remote sensing and in-situ scientific investigations of the planet Mars and its environment. As an exceptionally successful workhorse and a backbone of the Agency’s Science Programme in operation at Mars since end December 2003, Mars Express has proven to be a highly productive mission returning excellent scientific value for the investments made by ESA and its Member States. This paper is intended as the introduction to the series of papers that make this special collection. It briefly reviews the history of the mission, its science goals, its uniqueness while establishing its complementarity with other Mars missions in a collaborative context. It also lists the teams and operational aspects and innovations that made this mission a success. Then the paper highlights Mars Express’s scientific achievements throughout its 20-year lifetime. Mars Express results and discoveries continue playing an essential role in understanding the geological, atmospheric and climate evolution of the Red Planet and determining its potential past habitability. To conclude, a preview of the science and other topics covered by this collection is given. Mars Express, a pioneering mission for Europe at Mars, is currently continuing on its long scientific journey around the Red Planet.

Maritime shipping of vast quantities of liquid hydrogen (LH 2 ) will be necessary to facilitate a global hydrogen ecosystem; with some studies estimating volumes up to 172,000 m 3 for individual tanker ships, and requiring stationary storage tanks at terminals of 50,000 m 3 to 100,000 m 3 —ten to fifteen times larger than the current largest tank, located at launch pad B at NASA Kennedy Space Center (KSC). Such a radical scale-up will push the boundary of traditional, vacuum-insulated tank designs. Hence, a potential need exists for non-vacuum solutions, which necessitates exploring the thermal performance of insulation materials in non-condensable background gases at LH 2 temperatures, namely helium and hydrogen. Testing of two bulk-fill insulation materials common to large LH 2 storage tanks, perlite and glass bubbles, in helium and hydrogen was recently conducted by the Cryogenics Test Laboratory at KSC using the CS100 liquid nitrogen boiloff calorimeter per the ASTM C1774 standard methodology. Effective thermal conductivity (k e ) and heat flux (q) results for each insulation/gas combination are presented across the full vacuum range, as well as thermal profiles through the insulation thickness between 78 K and 293 K.