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On December 5, 2022, an indirect drive fusion implosion on the National Ignition Facility (NIF) achieved a target gain G_{target} of 1.5. This is the first laboratory demonstration of exceeding "scientific breakeven" (or G_{target}>1) where 2.05 MJ of 351 nm laser light produced 3.1 MJ of total fusion yield, a result which significantly exceeds the Lawson criterion for fusion ignition as reported in a previous NIF implosion [H. Abu-Shawareb et al. (Indirect Drive ICF Collaboration), Phys. Rev. Lett. 129, 075001 (2022)PRLTAO0031-900710.1103/PhysRevLett.129.075001]. This achievement is the culmination of more than five decades of research and gives proof that laboratory fusion, based on fundamental physics principles, is possible. This Letter reports on the target, laser, design, and experimental advancements that led to this result.

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Background: The first year of a child's life is a crucial time for child development. Current guidance about child health surveillance and health promotion programmes emphasises a partnership approach between health professionals and parents when it comes to child health care. Parents' voices have been largely absent from discussions about local child health programmes. For partnership working to be effective and for local services to be able to evolve effectively parents' views are vital., Objectives: This study aimed to explore parents' views on the child health surveillance and health promotion programmes offered during the first year of their child's life. The study aimed to be consumer-led through the involvement of lead parents in all stages of the research process., Methods: This study employed a qualitative methodology of focus groups and individual interviews. 35 participants were drawn from three general practices using a snowball sampling technique. Eligibility was determined as parents with a child under the age of one year or expecting a baby within the study timescale and registered at one of the 3 general practices. Focus groups were led by three 'parent-researchers' and individual interviews were conducted by a researcher. All focus groups and interviews were tape-recorded, transcribed and analysed using Atlas.Ti., Results: Several main themes were identified in this study. Firstly, when discussing scheduled health checks for children under one year of age parents expressed more positive feelings for the eight-week check which was seen to be comprehensive and informative rather than the eight-month check which was viewed as bureaucratic and less reassuring. Secondly, parents clearly articulated a need for reassurance and support from health professionals involved in child health surveillance and health promotion programmes. Thirdly, a crucial professional in the delivery of these programmes was the health visitor. Whilst parents expressed support for the concept of health visitors some health visitors were seen as bureaucratic and as making judgements of need based on socio-economic factors. Finally, some parents spoke of feeling excluded from accessing support as they were deemed not to be 'in need'., Conclusions: Wider concepts of partnership working between health professionals and parents, and, needs assessment are important to this study. Crucial elements of the partnership appear to be missing and this coupled with needs assessments that leave parents feeling excluded mean that there are discrepancies between expectations and experiences of parents. These issues require consideration in order to improve services and experiences.

Changes in the NMR chemical shifts of protons adjacent to the nitrogen atoms of Spermidine which are undergoing protonation have been measured by two-dimensional heteronuclear coupled NMR. Data thus obtained measure the dependence of the state of protonation of individual nitrogens on the pH, and permit calculation of the microprotonation constants of Spermidine and the concentrations of all of the variously protonated Spermidine species present at any pH.