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The aim of this study is to analyze the effects of a possible dam failure under various scenarios and to generate a flood hazard map for two consecutive dams located in a study area with a dense-residential region and a heavy-traffic highway. Two consecutive dams consist of Elmalı 2, a concrete-buttress dam and Elmalı 1, an earth-fill gravity dam in the upstream and downstream, respectively. Hydrologic Engineering Center-River Analysis System (HEC-RAS) was used to develop a dam failure model. Dam failure scenarios were examined regarding three main criteria: the Breach Formation Time (BFT), the Number of Failed Buttresses (NFB) of Elmalı 2, and the Reservoir Volume Ratio (RVR) of Elmalı 1. Accordingly, flood peak depth (Hp), peak flow rate (Qp), peak velocity (vp), and time to reach the peak (tp) are discussed. The results showed that BFT and NFB of Elmalı 2 were highly effective on these values, whereas RVR of Elmalı 1 had no significant effect. Moreover, the total area affected by potential floods was calculated with a comparative areal change analysis using flood inundation and flood hazard maps obtained. Estimated damage costs indicate that in the worst-case scenario, more than 500 buildings will be affected in the region.

Despite the looming land scarcity for agriculture, cropland abandonment is widespread globally. Abandoned cropland can be reused to support food security and climate change mitigation. Here, we investigate the potentials and trade-offs of using global abandoned cropland for recultivation and restoring forests by natural regrowth, with spatially-explicit modelling and scenario analysis. We identify 101 Mha of abandoned cropland between 1992 and 2020, with a capability of concurrently delivering 29 to 363 Peta-calories yr -1 of food production potential and 290 to 1,066 MtCO 2 yr -1 of net climate change mitigation potential, depending on land-use suitability and land allocation strategies. We also show that applying spatial prioritization is key to maximizing the achievable potentials of abandoned cropland and demonstrate other possible approaches to further increase these potentials. Our findings offer timely insights into the potentials of abandoned cropland and can inform sustainable land management to buttress food security and climate goals. This work demonstrates how global abandoned cropland is an untapped land resource. If recultivated and reforested strategically, it can provide substantial carbon sequestration and food production potential to support our shared climate and food security goals.

The Paris Agreement aims to limit global mean warming in the twenty-first century to less than 2 degrees Celsius above preindustrial levels, and to promote further efforts to limit warming to 1.5 degrees Celsius 1 . The amount of greenhouse gas emissions in coming decades will be consequential for global mean sea level (GMSL) on century and longer timescales through a combination of ocean thermal expansion and loss of land ice 2 . The Antarctic Ice Sheet (AIS) is Earth’s largest land ice reservoir (equivalent to 57.9 metres of GMSL) 3 , and its ice loss is accelerating 4 . Extensive regions of the AIS are grounded below sea level and susceptible to dynamical instabilities 5 – 8 that are capable of producing very rapid retreat 8 . Yet the potential for the implementation of the Paris Agreement temperature targets to slow or stop the onset of these instabilities has not been directly tested with physics-based models. Here we use an observationally calibrated ice sheet–shelf model to show that with global warming limited to 2 degrees Celsius or less, Antarctic ice loss will continue at a pace similar to today’s throughout the twenty-first century. However, scenarios more consistent with current policies (allowing 3 degrees Celsius of warming) give an abrupt jump in the pace of Antarctic ice loss after around 2060, contributing about 0.5 centimetres GMSL rise per year by 2100—an order of magnitude faster than today 4 . More fossil-fuel-intensive scenarios 9 result in even greater acceleration. Ice-sheet retreat initiated by the thinning and loss of buttressing ice shelves continues for centuries, regardless of bedrock and sea-level feedback mechanisms 10 – 12 or geoengineered carbon dioxide reduction. These results demonstrate the possibility that rapid and unstoppable sea-level rise from Antarctica will be triggered if Paris Agreement targets are exceeded. An observationally calibrated ice sheet–shelf model suggests that global warming of 3 °C will trigger rapid Antarctic ice loss, contributing about 0.5 cm per year of sea-level rise by 2100.

Antarctica’s ice shelves help to control the flow of glacial ice as it drains into the ocean, meaning that the rate of global sea-level rise is subject to the structural integrity of these fragile, floating extensions of the ice sheet 1 – 3 . Until now, data limitations have made it difficult to monitor the growth and retreat cycles of ice shelves on a large scale, and the full impact of recent calving-front changes on ice-shelf buttressing has not been understood. Here, by combining data from multiple optical and radar satellite sensors, we generate pan-Antarctic, spatially continuous coastlines at roughly annual resolution since 1997. We show that from 1997 to 2021, Antarctica experienced a net loss of 36,701 ± 1,465 square kilometres (1.9 per cent) of ice-shelf area that cannot be fully regained before the next series of major calving events, which are likely to occur in the next decade. Mass loss associated with ice-front retreat (5,874 ± 396 gigatonnes) has been approximately equal to mass change owing to ice-shelf thinning over the past quarter of a century (6,113 ± 452 gigatonnes), meaning that the total mass loss is nearly double that which could be measured by altimetry-based surveys alone. We model the impacts of Antarctica’s recent coastline evolution in the absence of additional feedbacks, and find that calving and thinning have produced equivalent reductions in ice-shelf buttressing since 2007, and that further retreat could produce increasingly significant sea-level rise in the future. Data from multiple satellite sensors show that Antarctica lost almost 37,000 km 2 of ice-shelf area from 1997 to 2021, and that calving losses are as important as ice-shelf thinning.

With the impending increase of the world population by 2050, more activities have been directed toward the improvement of crop yield and a safe environment. The need for chemical-free agricultural practices is becoming eminent due to the effects of these chemicals on the environment and human health. Actinomycetes constitute a significant percentage of the soil microbial community. The Streptomyces genus, which is the most abundant and arguably the most important actinomycetes, is a good source of bioactive compounds, antibiotics, and extracellular enzymes. These genera have shown over time great potential in improving the future of agriculture. This review highlights and buttresses the agricultural importance of Streptomyces through its biocontrol and plant growth-promoting activities. These activities are highlighted and discussed in this review. Some biocontrol products from this genus are already being marketed while work is still ongoing on this productive genus. Compared to more focus on its biocontrol ability, less work has been done on it as a biofertilizer until recently. This genus is as efficient as a biofertilizer as it is as a biocontrol.

Atmospheric warming threatens to accelerate the retreat of the Antarctic Ice Sheet by increasing surface melting and facilitating ‘hydrofracturing’ 1 – 7 , where meltwater flows into and enlarges fractures, potentially triggering ice-shelf collapse 3 – 5 , 8 – 10 . The collapse of ice shelves that buttress 11 – 13 the ice sheet accelerates ice flow and sea-level rise 14 – 16 . However, we do not know if and how much of the buttressing regions of Antarctica’s ice shelves are vulnerable to hydrofracture if inundated with water. Here we provide two lines of evidence suggesting that many buttressing regions are vulnerable. First, we trained a deep convolutional neural network (DCNN) to map the surface expressions of fractures in satellite imagery across all Antarctic ice shelves. Second, we developed a stability diagram of fractures based on linear elastic fracture mechanics to predict where basal and dry surface fractures form under current stress conditions. We find close agreement between the theoretical prediction and the DCNN-mapped fractures, despite limitations associated with detecting fractures in satellite imagery. Finally, we used linear elastic fracture mechanics theory to predict where surface fractures would become unstable if filled with water. Many regions regularly inundated with meltwater today are resilient to hydrofracture—stresses are low enough that all water-filled fractures are stable. Conversely, 60 ± 10 per cent of ice shelves (by area) both buttress upstream ice and are vulnerable to hydrofracture if inundated with water. The DCNN map confirms the presence of fractures in these buttressing regions. Increased surface melting 17 could trigger hydrofracturing if it leads to water inundating the widespread vulnerable regions we identify. These regions are where atmospheric warming may have the largest impact on ice-sheet mass balance. Using a neural network trained on continent-wide data and a fracture model, the ice shelves in Antarctica that may be prone to hydrofracturing under further atmospheric warming are identified.

Activation heat capacity is emerging as a crucial factor in enzyme thermoadaptation, as shown by the non-Arrhenius behaviour of many natural enzymes. However, its physical origin and relationship to the evolution of catalytic activity remain uncertain. Here we show that directed evolution of a computationally designed Kemp eliminase reshapes protein dynamics, which gives rise to an activation heat capacity absent in the original design. These changes buttress transition-state stabilization. Extensive molecular dynamics simulations show that evolution results in the closure of solvent-exposed loops and a better packing of the active site. Remarkably, this gives rise to a correlated dynamical network that involves the transition state and large parts of the protein. This network tightens the transition-state ensemble, which induces a negative activation heat capacity and non-linearity in the activity–temperature dependence. Our results have implications for understanding enzyme evolution and suggest that selectively targeting the conformational dynamics of the transition-state ensemble by design and evolution will expedite the creation of novel enzymes.Computationally designed enzymes can be substantially improved by directed evolution. Now, it has been shown that evolution can introduce a dynamic network that selectively tightens the transition-state ensemble, giving rise to a negative activation heat capacity. Targeting such transition state conformational dynamics may expedite de novo enzyme creation.

This research shows the photogrammetric survey and graphic documentation of the cloister of the Cathedral of the Assumption of the Virgin Mary and San Frutos in the city of Segovia, Spain.The building consists of a series of architectural elements dating back to the Renaissance period. Segovia Cathedral, dedicated to Our Lady of the Assumption and San Frutos, is a masterpiece of Gothic and Renaissance architecture. It represents an icon of the Christian faith and a cultural-historical point in Spanish history.The building was erected in the 16th century (1525–1577), when Renaissance architecture was flourishing in much of Europe. The research analyzes the context through the methodology of architectural drawing in order to propose knowledge and paths of fruition and enhancement. In the stages of the research, it was considered useful to divide the monumental building from the cloister in order to expand the possibilities of a more direct knowledge of the open layout towards the central courtyard. Particularly interesting is the system of vaults and buttresses that characterize the ceilings of the Cloister.The results achieved highlight an understanding of the vaulted system in relation to the planimetric space, completely divorced from the city and able to allow the passage of the religious in moments of solitude and prayer.

Retaining wall movements are often estimated from a datum at the start of soil excavation. However, recent studies indicate that significant wall movements may occur during pre-excavation dewatering. In this study, the effectiveness of a buttress wall (that is, a short length of wall at 90° to the main wall) in limiting wall movement during pre-excavation dewatering is investigated numerically, focusing in particular on the buttress wall length (LB). Results indicate that wall movement decreases as LB increases. However, a smaller LB (less than 50% of the excavation width) may be sufficient if the drawdown or pumped depth is small (less than 30% of the total depth of retaining wall). With drawdowns greater than 60% of the total wall depth, a larger LB (greater than 75% of the excavation width) is needed to effectively control the deformation.

Floating ice shelves, which fringe most of Antarctica’s coastline, regulate ice flow into the Southern Ocean1–3. Their thinning4–7 or disintegration8,9 can cause upstream acceleration of grounded ice and raise global sea levels. So far the effect has not been quantified in a comprehensive and spatially explicit manner. Here, using a finite-element model, we diagnose the immediate, continent-wide flux response to different spatial patterns of ice-shelf mass loss. We show that highly localized ice-shelf thinning can reach across the entire shelf and accelerate ice flow in regions far from the initial perturbation. As an example, this ‘tele-buttressing’ enhances outflow from Bindschadler Ice Stream in response to thinning near Ross Island more than 900 km away. We further find that the integrated flux response across all grounding lines is highly dependent on the location of imposed changes: the strongest response is caused not only near ice streams and ice rises, but also by thinning, for instance, well-within the Filchner–Ronne and Ross Ice Shelves. The most critical regions in all major ice shelves are often located in regions easily accessible to the intrusion of warm ocean waters10–12, stressing Antarctica’s vulnerability to changes in its surrounding ocean.