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Flooding is a pervasive natural hazard with wide-ranging impacts on society. Using a high-resolution global flood model considering coastal, fluvial, and pluvial hazards, we clarify the role of climate effects versus population growth effects in changing flood exposure. Between 2020 and 2100, the population likely exposed to 1% annual risk (100-year) flood hazard will increase from 1.6 to 1.9 billion people. Of this change from the 2020 exposure, we attribute 21.1% to climate change, 76.8% to population change, and 2.1% to both climate and population change. The largest driver of uncertainty in exposure is population change, while climate change remains a smaller but still important driver. The global increase in exposure between 2020 and 2100 is primarily driven by low-GDP regions, and by 2100 the lowest GDP areas will make up 63% of the exposure both overall and in urban areas. Urban areas are especially vulnerable in nearly all global regions, and urban areas sensitive to extreme events are expected to see a 33% increase in population exposure. This study highlights the vast inequities in flood exposure, and future work should direct resources and strategies toward sustainable risk mitigation in these areas. This study explores how climate change and population growth shape flood exposure. By 2100, exposure could rise from 1.6 to 1.9 billion people, driven 21% by climate change and 77% by population growth, with low-income and urban regions most affected.

Coral bleaching is the detrimental expulsion of algal symbionts from their cnidarian hosts, and predominantly occurs when corals are exposed to thermal stress. The incidence and severity of bleaching is often spatially heterogeneous within reef-scales (<1 km), and is therefore not predictable using conventional remote sensing products. Here, we systematically assess the relationship between in situ measurements of 20 environmental variables, along with seven remotely sensed SST thermal stress metrics, and 81 observed bleaching events at coral reef locations spanning five major reef regions globally. We find that high-frequency temperature variability (i.e., daily temperature range) was the most influential factor in predicting bleaching prevalence and had a mitigating effect, such that a 1 °C increase in daily temperature range would reduce the odds of more severe bleaching by a factor of 33. Our findings suggest that reefs with greater high-frequency temperature variability may represent particularly important opportunities to conserve coral ecosystems against the major threat posed by warming ocean temperatures. Coral bleaching is often predicted via remote sensing of ocean temperatures at large scales, obscuring important reef-scale drivers and biological responses. Here, the authors use in- situ data to show that bleaching is lower globally at reef habitats with greater diurnal temperature variability.

As ocean temperatures rise, understanding the cooling role of internal waves is crucial for reef preservation. Climate‐induced surface warming increases stratification, altering internal wave propagation. We use high‐resolution, nonhydrostatic simulations at Dongsha Atoll in the South China Sea to explore seasonal bottom temperature changes affecting benthic ecosystems for climate scenario SSP5‐8.5 for 2020 and 2100. Our findings show internal waves transport cooler, deeper waters into shallow areas, reducing warming by up to 2.3°C relative to conditions without waves. Enhanced stratification and internal tide forcing in a warmer, more strongly stratified ocean increases wave‐driven cooling by up to 0.5°C in shallow zones. Variability in bottom temperature are also enhanced by up to 4.5°C. However, net warming by 2100 is projected at up to 2.8°C in shallow areas and 0.9°C in deeper regions. Areas with strong internal wave activity could serve as thermal refugia, despite overall trends pointing to continued ocean warming.

The ε4 allele of the apolipoprotein E ( APOE ) gene, a genetic risk factor for Alzheimer’s disease, is abundantly expressed in both the brain and periphery. Here, we present evidence that peripheral apoE isoforms, separated from those in the brain by the blood–brain barrier, differentially impact Alzheimer’s disease pathogenesis and cognition. To evaluate the function of peripheral apoE, we developed conditional mouse models expressing human APOE3 or APOE4 in the liver with no detectable apoE in the brain. Liver-expressed apoE4 compromised synaptic plasticity and cognition by impairing cerebrovascular functions. Plasma proteome profiling revealed apoE isoform-dependent functional pathways highlighting cell adhesion, lipoprotein metabolism and complement activation. ApoE3 plasma from young mice improved cognition and reduced vessel-associated gliosis when transfused into aged mice, whereas apoE4 compromised the beneficial effects of young plasma. A human induced pluripotent stem cell-derived endothelial cell model recapitulated the plasma apoE isoform-specific effect on endothelial integrity, further supporting a vascular-related mechanism. Upon breeding with amyloid model mice, liver-expressed apoE4 exacerbated brain amyloid pathology, whereas apoE3 reduced it. Our findings demonstrate pathogenic effects of peripheral apoE4, providing a strong rationale for targeting peripheral apoE to treat Alzheimer’s disease. Mouse models expressing liver apoE in the absence of brain apoE reveal detrimental effects of peripheral apoE4 associated with Alzheimer’s risk on cognition and amyloid pathology through compromising vascular integrity and function.

Flow over complex terrain causes stress on the bottom leading to drag, turbulence, and formation of a boundary layer. But despite the importance of the hydrodynamic roughness scale z 0 in predicting flows and mixing, little is known about its connection to complex terrain. To address this gap, we conducted extensive field observations of flows and finescale measurements of bathymetry using fluid-lensing techniques over a shallow coral reef on Ofu, American Samoa. We developed a validated centimeter-scale nonhydrostatic hydrodynamic model of the reef, and the results for drag compare well with the observations. The total drag is caused by pressure differences creating form drag and is only a function of relative depth and spatially averaged streamwise slope, consistent with scaling for k – δ -type roughness, where k is the roughness height and δ is the boundary layer thickness. We approximate the complex reef surface as a superposition of wavy bedforms and present a simple method for predicting z 0 from the spatial root-mean-square of depth and streamwise slope of the bathymetric surface and a linear coefficient a 1 , similar to results from other studies on wavy bedforms. While the local velocity profiles vary widely, the horizontal average is consistent with a log-layer approximation. The model grid resolution required to accurately compute the form drag is O (10–50) times the dominant horizontal hydrodynamic scale, which is determined by a peak in the spectra of the streamwise slope. The approach taken in this study is likely applicable to other complex terrains and could be explored for other settings.

Explore the Jewish traditions preserved in the commentaries of a largely neglected Alexandrian Christian exegete Justin M. Rogers surveys commentaries on Genesis, Job, Psalms, Ecclesiastes, and Zechariah by Didymus the Blind (ca. 313-398 CE), who was regarded by his students as one of the greatest Christian exegetes of the fourth century. Rogers highlights Didymus's Jewish sources, zeroing in on traditions of Philo of Alexandria, whose treatises were directly accessible to Didymus while he was authoring his exegetical works. Philonic material in Didymus is covered by extensive commentary, demonstrating that Philo was among the principle sources for the exegetical works of Didymus the Blind. Rogers also explores the mediating influence of the Alexandrian Christian tradition, focusing especially on the roles of Clement and Origen. Features Fresh incites into the Alexandrian Christian reception of PhiloA thorough discussion of Didymus's exegetical method, particularly in theCommentary on GenesisExamination of the use and importance of Jewish and Christian sources in Late Antique Christian commentaries

Depth is used often as a proxy for gradients in energetic resources on coral reefs and for predicting patterns of community energy use. With increasing depth, loss of light can lead to a reduced reliance on autotrophy and an increased reliance on heterotrophy by mixotrophic corals. However, the generality of such trophic zonation varies across contexts. By combining high-resolution oceanographic measurements with isotopic analyses (δ13C, δ15N) of multiple producer and consumer levels across depths (10–30 m) at a central Pacific oceanic atoll, we show trophic zonation in mixotrophic corals can be both present and absent within the same reef system. Deep-water internal waves that deliver cool particulate-rich waters to shallow reefs occurred across all sites (2.5–5.6 events week−1 at 30 m) but the majority of events remained depth-restricted (4.3–9.7% recorded at 30 m propagated to 10 m). In the absence of other particulate delivery, mixotrophs increased their relative degree of heterotrophy with increasing depth. However, where relatively long-lasting downwelling events (1.4–3.3 times the duration of any other site) occurred simultaneously, mixotrophs displayed elevated and consistent degrees of heterotrophy regardless of depth. Importantly, these long-lasting surface pulses were of a lagoonal origin, an area of rich heterotrophic resource supply. Under such circumstances, we hypothesize heterotrophic resource abundance loses its direct linkage with depth and, with resources readily available at all depths, trophic zonation is no longer present. Our results show that fine-scale intra-island hydrographic regimes and hydrodynamic connectivity between reef habitats contribute to explaining the context specific nature of coral trophic depth zonation in shallow reef ecosystems.

Spur-and-groove (SAG) morphology characterizes the fore reef of many coral reefs worldwide. Although the existence and geometrical properties of SAG have been well documented, an understanding of the hydrodynamics over them is limited. Here, the three-dimensional flow patterns over SAG formations, and a sensitivity of those patterns to waves, currents, and SAG geometry were characterized using the physics-based Delft3D-FLOW and SWAN models. Shore-normal shoaling waves over SAG formations were shown to drive two circulation cells: a cell on the lower fore reef with offshore flow over the spurs and onshore flow over the grooves, except near the seabed where velocities were always onshore, and a cell on the upper fore reef with offshore surface velocities and onshore bottom currents, which result in depth-averaged onshore and offshore flow over the spurs and grooves, respectively. The mechanism driving this flow results from the net of the radiation stress gradients and pressure gradient, which is balanced by the Reynolds stress gradients and bottom friction that differ over the spur and over the groove. Waves were the primary driver of variations in modelled flow over SAG, with the flow strength increasing for increasing wave heights and periods. Spur height, SAG wavelength, and the water depth at peak spur height were the dominant influences on the hydrodynamics, with spur heights directly proportional to the strength of SAG circulation cells. SAG formations with shorter SAG wavelengths only presented one circulation cell on the shallower portion of the reef, as opposed to the two circulation cells for longer SAG wavelengths. SAG formations with peak spur heights occurring in shallower water had stronger circulation than those with peak spur heights occurring in deeper water. These hydrodynamic patterns also likely affect coral and reef development through sediment and nutrient fluxes.

This paper presents findings from a study that explored the experiences of young people living in foster-care in the UK. Previous research highlights that children and young people in foster-care experience stigma. Qualitative methods were chosen to explore how the young people in this study experience and manage stigma in their day-to-day lives. Findings provide valuable insights into how the participants cope with the challenges of stigma. There were two key ways they did this: (i) by carefully managing the disclosure of their 'in-care' status and (ii) by drawing support from their social relationships. Furthermore, the participants particularly valued support from their peers who were also living in foster-care, as it enabled them to form an in-group, which presented them with a valuable sense of belonging. These findings have implications for practice and this paper proposes two ways to better support young people in foster-care to cope with stigma: first, by valuing the importance of friendship groups and enabling young people to maintain their existing friendships and, second, by developing more opportunities that bring fostered young people together, which enables them to interact with their peers without the pressure of managing stigma.