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Abstract Marine and coastal tourism deliver economic benefits to coastal communities that far surpass those generated by fisheries, yet its potential contribution to global marine conservation remains underexamined. Marine Protected Areas (MPAs) help restore biodiversity and enhance nearby fisheries, but their direct tourism benefits are not well understood. Here, we estimate the global demand for recreational scuba dive tourism, map the distribution and protection status of all marine dive sites globally, and develop a bioeconomic model to estimate the revenue gains from upgrading unprotected dive sites to fully protected MPAs. We estimate that 33.1 million scuba dives occur annually in marine environments worldwide, with 70% taking place within MPAs. However, only 15% of these MPA-affiliated dive sites are highly or fully protected. We show that designating all unprotected recreational dive sites, representing less than 1% of the global ocean, as highly or fully protected MPAs would improve fish biomass and biodiversity while generating an additional US$2 billion per year in direct tourism revenue (not including economic multipliers). Importantly, 62% of marine diving currently occurs in developing countries, underscoring the potential for dive tourism to support both marine conservation and local livelihoods in regions where such benefits are most needed.

Abstract We propose the lag‐1 autocorrelation of daily precipitation as a simple diagnostic of tropical precipitation variability in climate models. This metric generally has a relatively uniform distribution of positive values across the tropics. However, selected land regions are characterized by exceptionally low autocorrelation values. Low values correspond to the dominance of high frequency variance in precipitation, and specifically of high frequency convectively coupled equatorial waves. Consistent with previous work, we show that CMIP6 climate models overestimate the autocorrelation. Global kilometer‐scale models capture the observed autocorrelation when deep convection is explicitly simulated. When a deep convection parameterization is used, though, the autocorrelation increases over land and ocean, suggesting that land surface‐atmosphere interactions are not responsible for the changes in autocorrelation. Furthermore, the metric also tracks the accuracy of the representation of the relative importance of high frequency and low frequency convectively coupled equatorial waves in the models.

Abstract Harmful, capacity-enhancing subsidies distort fishing activities and lead to overfishing and perverse outcomes for food security and conservation. We investigated the provision and spatial distribution of fisheries subsidies in the Indian Ocean. Total fisheries subsidies in the Indian Ocean, estimated at USD 3.2 billion in 2018, were mostly harmful subsidies (60%), provided to the large-scale industrial sector by mainly a few subsidising countries, including Distant Water Fishing countries. We also explored possible socio-economic drivers of the composition of subsidies, and show that the extent of harmful subsidies provided by Indian Ocean Rim (IOR) countries to their industrial sector can be predicted by the seafood export quantities of these countries. These results illustrate the inequity in accessing fisheries resources for the small-scale sector of nutrient insecure and ocean-dependant IOR countries. The present study can benchmark future assessments and implementation of fisheries subsidy disciplines in the region following the World Trade Organisation Agreement on Fisheries Subsidies.

Solar power tower plants that are operated with molten salt offer the advantage that the molten salt can be used as a heat transfer medium as well as storage medium. Consequently, solar energy can be stored easily and efficiently in only one loop without transformation losses. Furthermore, by using large-scale storage facilities, almost a 24/7 base load operation is possible. Since the molten salt begin to crystallize at temperature of 238 °C, the absorber tube must be preheated before the plants’ operation can begin. During the preheating a subset of heliostats will be aimed on the receiver surface to ensure a solar flux density that leads to tube temperatures above the solar salt crystallization point. Since the absorber tubes are empty during the preheating, there is a risk of high temperature gradients and transients and thus high thermal stresses that may lead to fatigue damage. To prevent this, a preheating strategy for a molten salt test receiver was developed and tested, taking into account ambient conditions and time. The present work shows the results of the commissioning of the developed preheating strategy and discusses its potential for improvement.

Marine and coastal tourism deliver economic benefits to coastal communities that far surpass those generated by fisheries, yet its potential contribution to global marine conservation remains underexamined. Marine Protected Areas (MPAs) help restore biodiversity and enhance nearby fisheries, but their direct tourism benefits are not well understood. Here, we estimate the global demand for recreational scuba dive tourism, map the distribution and protection status of all marine dive sites globally, and develop a bioeconomic model to estimate the revenue gains from upgrading unprotected dive sites to fully protected MPAs. We estimate that 33.1 million scuba dives occur annually in marine environments worldwide, with 70% taking place within MPAs. However, only 15% of these MPA-affiliated dive sites are highly or fully protected. We show that designating all unprotected recreational dive sites, representing less than 1% of the global ocean, as highly or fully protected MPAs would improve fish biomass and biodiversity while generating an additional US$2 billion per year in direct tourism revenue (not including economic multipliers). Importantly, 62% of marine diving currently occurs in developing countries, underscoring the potential for dive tourism to support both marine conservation and local livelihoods in regions where such benefits are most needed. [ABSTRACT FROM AUTHOR]

Abstract The diagnosis of chronic lyme neuroborreliosis can be a challenge even for experienced neurologists. The clinical picture may be multifaceted, including polyradiculitis to cranial nerve palsies, meningitis, encephalomyelitis, encephalopathy and peripheral neuropathy. We report on a patient presenting with basal leptomeningoencephalitis associated with vasculopathy where the chemokine CXCL13 in cerebrospinal fluid played an important diagnostic role.

The magnitude of subsidies provided to the fishing sector by governments worldwide is immense—an estimated $35.4 billion USD per year. The majority of these subsidies may be impeding efforts to sustainably manage fisheries by incentivizing overfishing and overcapacity. Recognizing the threat these subsidies pose, the World Trade Organization has set a goal of reaching an agreement that would end fisheries subsidies that contribute to overcapacity, overfishing, and illegal fishing. However, negotiations have been hampered by uncertainty around the likely effects of reforming these subsidies. Here we present a novel method for translating a bioeconomic model into an interactive online decision support tool that draws upon real-world data on fisheries subsidies and industrial fishing activity so users can directly compare the relative ambition levels of different subsidy reform options.

We propose the lag‐1 autocorrelation of daily precipitation as a simple diagnostic of tropical precipitation variability in climate models. This metric generally has a relatively uniform distribution of positive values across the tropics. However, selected land regions are characterized by exceptionally low autocorrelation values. Low values correspond to the dominance of high frequency variance in precipitation, and specifically of high frequency convectively coupled equatorial waves. Consistent with previous work, we show that CMIP6 climate models overestimate the autocorrelation. Global kilometer‐scale models capture the observed autocorrelation when deep convection is explicitly simulated. When a deep convection parameterization is used, though, the autocorrelation increases over land and ocean, suggesting that land surface‐atmosphere interactions are not responsible for the changes in autocorrelation. Furthermore, the metric also tracks the accuracy of the representation of the relative importance of high frequency and low frequency convectively coupled equatorial waves in the models. Plain Language Summary: Rainfall in the tropics is influenced by many atmospheric processes that depend on geographic location. We use the lag‐1 autocorrelation as a metric for the day‐to‐day persistence of rainfall. We find that rainfall is very persistent in most parts of the tropics with a few exceptions over land, for example, the Sahel, where high frequency rainfall events dominate. Our results show that models with a horizontal resolution of a few kilometers reproduce the autocorrelation, in contrast to coarser climate models. We also analyze atmospheric waves and find that they are important for the autocorrelation pattern in the observations and the simulations. Key Points: The lag‐1 autocorrelation pattern of daily precipitation in the tropics is robust across different observation‐based data setsThe lag‐1 autocorrelation reflects the relative variance of high frequency and low frequency convectively coupled equatorial wavesKilometer‐scale models capture the observed autocorrelation, but models with parameterized deep convection overestimate it [ABSTRACT FROM AUTHOR]

In 2015 the Sustainable Development Goals of the United Nations stipulated that certain forms of subsidies that the fishing sector receive must be prohibited. However, the global fishing sector is complex and varied, and as such there remains a need for information on the distribution of subsidies between the different regions and their sub-sectors. This bottom-up study therefore provides up-dated and improved analyses of the financial support fishing sub-sectors receive from public entities. Estimates show that of the USD 35.4 billion of global fisheries subsidies provided in 2018, 19% went to the small-scale fishing sub-sector (SSF), including artisanal, and subsistence fisheries. Whilst more than 80% went to the large-scale (industrial) fishing sub-sector (LSF). Analysis by subsidy category and type shows, for example, that the majority of the subsidies that the LSF receive are in the form of capacity-enhancing subsidies (USD 18.3 billion) with fuel subsidies being the highest overall subsidy type (USD 7.2 billion). Fuel subsidies are especially harmful as they perpetuate fuel inefficient technology. Since the last estimate of the global fisheries subsidies divide, the percentage of capacity-enhancing subsidies within the SSF has increased from 41% in 2009 to 59% in 2018. When assessing the level of subsidization per active fisher at the global scale, a fisher involved in LSF receives disproportionally (3.5 times) more subsidies than a fisher involved in SSF and in terms of subsidies per landed value LSF receive twice as many subsidies per dollar landed than SSF. This unequal distribution of government support exacerbates the ongoing political and economic marginalization of SSF, globally. The Sustainable Development Goals and the supporting science are quite clear, we must remove all capacity-enhancing subsidies across all sub-sectors and regions which exacerbate overcapacity and overfishing, in order to ensure the sustainability of our fish stocks. Our recommendation is that capacity-enhancing subsidies be removed and instead used to support fishers through coastal fishing community projects that focus on fisheries sustainability, social justice and food security, rather than on reducing the cost of fishing or artificially enhancing profits through the provision of harmful subsidization.

We report on our first results of a dispersion-managed monolithic polarization-maintaining ultrafast Thulium-doped fiber oscillator. The design incorporates only commercially available polarization-maintaining components and emits linearly polarized light with a polarization extinction ratio of over 17 dB . The observed optical pulse spectra with up to 10 nm width centered at 1961.5 nm beyond the water absorption lines support sub-1 ps pulse duration. The simple linear configuration and the wide spread availability of the used low cost polarization-maintaining fiber components makes the presented oscillator a valuable concept for an environmental stable seed source.