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Background: Children with medical complexity (CMC) represent a small, but growing, proportion of all children. Regardless of their underlying diagnosis, by definition, all CMC have similar functional limitations and high healthcare needs. It has been suggested that improving aspects of healthcare delivery for CMC improves health- and quality of life-related outcomes for children and their families and reduces healthcare-related expenditure. As a result, dedicated comprehensive care programmes have been established at many hospitals to meet the needs of CMC; however, it is unclear if such programmes are effective., Objectives: Our main objective was to assess the effectiveness of comprehensive care programmes that aim to improve care coordination and other aspects of health care for CMC and to assess whether the effectiveness of such programmes differs according to the programme setting and structure. We aimed to assess their effectiveness in relation to child and parent health, functioning, and quality of life, quality of care, number of healthcare encounters, unmet healthcare needs, and total healthcare-related costs., Search Methods: We searched CENTRAL, MEDLINE, Embase, and CINAHL in May 2023. We also searched reference lists, trial registries, and the grey literature., Selection Criteria: Randomised and non-randomised trials, controlled before-after studies, and interrupted time series studies were included. Studies that compared enrolment in a comprehensive care programme with non-enrolment in such a programme/treatment as usual were included. Participants were children that met the criteria for the definition of CMC, which is: having (i) a chronic condition, (ii) functional limitations, (iii) increased health and other service needs, and (iv) increased healthcare costs. Studies that included the following types of outcomes were included: health; quality of care; utilisation, coverage and access; resource use and costs; equity; and adverse outcomes., Data Collection and Analysis: Two review authors independently extracted data, assessed the risk of bias in each included study, and evaluated the certainty of evidence according to GRADE criteria. Where possible, data were represented in forest plots and pooled. We were unable to undertake a meta-analysis for comparisons and outcomes, so we used a structured synthesis approach., Main Results: We included four studies with a total of 912 CMC as participants. All included studies were randomised controlled trials conducted in hospitals in the USA or Canada. Participants varied across the included studies; however, all four studies included children with complex and chronic illness and high healthcare needs. While the primary aim of the intervention was similar across all four studies, the components of the interventions differed: in the four studies, the intervention involved some element of care coordination; in two of the studies, it involved the child receiving care from a multidisciplinary team, while in one study, the intervention was primarily centred on access to an advanced practice nurse care coordinator and another study involved nurse a practitioner-paediatrician dyad partnering with families. The risk of bias in the four studies varied across domains, with issues primarily relating to the lack of blinding of participants, personnel, and outcome assessors, inadequate allocation concealment, and incomplete outcome data. Comprehensive care for CMC compared to usual care may make little to no difference to child health, functioning, and quality of life at 12 or 24 months (three studies with 404 participants) and we assessed the evidence for the outcomes in this category (child health-related quality of life and functional status) as being of low certainty. For CMC, comprehensive care probably makes little or no difference to parent health, functioning, and quality of life compared to usual care at 12 months (one study with 117 participants) and we assessed the evidence for this outcome as being of moderate certainty. Comprehensive care for CMC compared to usual care may slightly improve child and family satisfaction with, and perceptions of, care and service delivery at 12 months (three studies with 453 participants); however, we assessed the evidence for these outcomes as being of low certainty. For CMC, comprehensive care probably makes little or no difference to the number of healthcare encounters (emergency department visits) and the number of hospitalised days (hospital admissions) compared to usual care at 12 months (three studies with 668 participants), and we assessed the evidence for these outcomes as being of moderate certainty. Three of the included studies (668 participants) reported cost outcomes and had conflicting results, with one study reporting significantly lower healthcare costs at 12 months in the intervention group compared to the control group, one reporting no differences between groups, and the other study reporting a greater increase in total healthcare costs in the intervention group compared to the control group. Overall, comprehensive care may make little or no difference to overall healthcare costs in CMC; however, the methods used to measure total healthcare costs varied across studies and the certainty of the evidence relating to this outcome is low. No studies assessed the costs to the family., Authors' Conclusions: The findings of this review should be treated with caution due to the limited amount and quality of the published research that was available to be included. Overall, the certainty of the evidence for the effectiveness of comprehensive care for CMC ranged from low to moderate across outcomes and there is currently insufficient evidence on which to draw strong conclusions. There is a need for more high-quality randomised trials with consistency of the target population and intervention components, methods of reporting outcomes, and follow-up periods, as well as full cost analyses, taking into account both costs to the family and costs to the healthcare system., (Copyright © 2024 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.)

Mesoscale eddies are ubiquitous features of ocean circulation that modulate the supply of nutrients to the upper sunlit ocean, influencing the rates of carbon fixation and export. The popular eddy-pumping paradigm implies that nutrient fluxes are enhanced in cyclonic eddies because of upwelling inside the eddy, leading to higher phytoplankton production. We show that this view does not hold for a substantial portion of eddies within oceanic subtropical gyres, the largest ecosystems in the ocean. Using space-based measurements and a global biogeochemical model, we demonstrate that during winter when subtropical eddies are most productive, there is increased chlorophyll in anticyclones compared with cyclones in all subtropical gyres (by 3.6 to 16.7% for the five basins). The model suggests that this is a consequence of the modulation of winter mixing by eddies. These results establish a new paradigm for anticyclonic eddies in subtropical gyres and could have important implications for the biological carbon pump and the global carbon cycle.

Geo-engineering proposals to mitigate global warming have focused either on methods of carbon dioxide removal, particularly nutrient fertilization of plant growth, or on cooling the Earth's surface by reducing incoming solar radiation (shading). Marine phytoplankton contribute half the Earth's biological carbon fixation and carbon export in the ocean is modulated by the actions of microbes and grazing communities in recycling nutrients. Both nutrients and light are essential for photosynthesis, so understanding the relative influence of both these geo-engineering approaches on ocean ecosystem production and processes is critical to the evaluation of their effectiveness. In this paper, we investigate the relationship between light and nutrient availability on productivity in a stratified, oligotrophic subtropical ocean ecosystem using a one-dimensional water column model coupled to a multi-plankton ecosystem model, with the goal of elucidating potential impacts of these geo-engineering approaches on ecosystem production. We find that solar shading approaches can redistribute productivity in the water column but do not change total production. Macronutrient enrichment is able to enhance the export of carbon, although heterotrophic recycling reduces the efficiency of carbon export substantially over time. Our results highlight the requirement for a fuller consideration of marine ecosystem interactions and feedbacks, beyond simply the stimulation of surface blooms, in the evaluation of putative geo-engineering approaches.

Using an extensive database of in situ observations we present a model that estimates the particle backscattering coefficient as a function of the total chlorophyll concentration in the open-ocean (Case-1 waters). The parameters of the model include a constant background component and the chlorophyll-specific backscattering coefficients associated with small (<20 μm) and large (>20 μm) phytoplankton. The new model performed with similar accuracy when compared with a traditional power-law function, with the additional benefit of providing information on the role of phytoplankton size. The observed spectral-dependency (γ) of model parameters was consistent with past observations, such that γ associated with the small phytoplankton population was higher than that of large phytoplankton. Furthermore, γ associated with the constant background component suggests this component is likely attributed to submicron particles. We envisage that the model would be useful for improving Case-1 ocean-colour models, assimilating light into multi-phytoplankton ecosystem models and improving estimates of phytoplankton size structure from remote sensing.

Using the phytoplankton size-class model of Brewin et al. [Ecol. Model.221, 1472 (2010)], the two-population absorption model of Sathyendranath et al. [Int. J. Remote. Sens.22, 249 (2001)] and Devred et al. [J. Geophys. Res.111, C03011 (2006)] is extended to three populations of phytoplankton, namely, picophytoplankton, nanophytoplankton, and microphytoplankton. The new model infers total and size-dependent phytoplankton absorption as a function of the total chlorophyll-a concentration. A main characteristic of the model is that all the parameters that describe it have biological or optical interpretation. The three-population model performs better than the two-population model at retrieving total phytoplankton absorption. Accounting for the contributions of picophytoplankton and nanophytoplankton, rather than the combination of both as in the two-population model, improved significantly the retrieval of phytoplankton absorption at low chlorophyll-a concentrations. Class-dependent specific absorption of phytoplankton derived using the model compares well with previously published models. However, the model presented in this paper provides the specific absorption of three size classes and is applicable to a continuum of chlorophyll-a concentrations. Absorption obtained from remotely sensed chlorophyll-a using our model compares well with in situ absorption measurements.

Adaptive management of the marine environment requires an understanding of the complex interactions within it. Establishing levels of natural variability within and between marine ecosystems is a necessary prerequisite to this process and requires a monitoring programme which takes account of the issues of time, space and scale. In this paper, we argue that an ecosystem approach to managing the marine environment should take direct account of climate change indicators at a regional level if it is to cope with the unprecedented change expected as a result of human impacts on the earth climate system. We discuss the purpose of environmental monitoring and the importance of maintaining long-term time series. Recommendations are made on the use of these data in conjunction with modern extrapolation and integration tools (e.g. ecosystem models, remote sensing) to provide a diagnostic approach to the management of marine ecosystems, based on adaptive indicators and dynamic baselines.

Long-term research in the western English Channel, undertaken by the marine laboratories in Plymouth, is described and details of survey methods, sites, and time series given in this chapter. Major findings are summarized and their limitations outlined. Current research, with recent reestablishment and expansion of many sampling programmes, is presented, and possible future approaches are indicated. These unique long-term data sets provide an environmental baseline for predicting complex ecological responses to local, regional, and global environmental change. Between 1888 and the present, investigations have been carried out into the physical, chemical, and biological components (ranging from plankton and fish to benthic and intertidal assemblages) of the western English Channel ecosystem. The Marine Biological Association of the United Kingdom has performed the main body of these observations. More recent contributions come from the Continuous Plankton Recorder Survey, now the Sir Alister Hardy Foundation for Ocean Science, dating from 1957; the Institute for Marine Environmental Research, from 1974 to 1987; and the Plymouth Marine Laboratory, which was formed by amalgamation of the Institute for Marine Environmental Research and part of the Marine Biological Association, from 1988. Together, these contributions constitute a unique data series-one of the longest and most comprehensive samplings of environmental and marine biological variables in the world. Since the termination of many of these time series in 1987-1988 during a reorganisation of UK marine research, there has been a resurgence of interest in long-term environmental change. Many programmes have been restarted and expanded with support from several agencies. The observations span significant periods of warming (1921-1961; 1985-present) and cooling (1962-1980). During these periods of change, the abundance of key species underwent dramatic shifts. The first period of warming saw changes in zooplankton, pelagic fish, and larval fish, including the collapse of an important herring fishery. During later periods of change, shifts in species abundances have been reflected in other assemblages, such as the intertidal zone and the benthic fauna. Many of these changes appear to be related to climate, manifested as temperature changes, acting directly or indirectly. The hypothesis that climate is a forcing factor is widely supported today and has been reinforced by recent studies that show responses of marine organisms to climatic attributes such as the strength of the North Atlantic Oscillation. The long-term data also yield important insights into the effects of anthropogenic disturbances such as fisheries exploitation and pollution. Comparison of demersal fish hauls over time highlights fisheries effects not only on commercially important species but also on the entire demersal community. The effects of acute ("Torrey Canyon" oil spill) and chronic (tributyltin [TBT] antifoulants) pollution are clearly seen in the intertidal records. Significant advances in diverse scientific disciplines have been generated from research undertaken alongside the long-term data series. Many concepts in marine biological textbooks have originated in part from this work (e.g. the seasonal cycle of plankton, the cycling of nutrients, the pelagic food web trophic interactions, and the influence of hydrography on pelagic communities). Associated projects currently range from studies of marine viruses and bacterial ecology to zooplankton feeding dynamics and validation of ocean colour satellite sensors. Recent advances in technology mean these long-term programmes are more valuable than ever before. New technology collects data on finer temporal and spatial scales and can be used to capture processes that operate on multiple scales and help determine their influence in the marine environment. The MBA has been in the forefront of environmental modelling of shelf seas since the early 1970s. Future directions being pursued include the continued development of coupled physical-ecosystem models using western English Channel time-series data. These models will include both the recent high-resolution data and the long-term time-series information to predict effects of future climate change scenarios. It would be beneficial to provide more spatial and high-resolution temporal context to these data, which are fundamental for capturing processes that operate at multiple scales and understanding how they operate within the marine environment. This is being achieved through employment of technologies such as satellite-derived information and advanced telemetry instruments that provide real-time in situ profile data from the water column.