Using Your Beam Efficiently: Reducing Electron Dose in the STEM via Flyback Compensation

In the scanning transmission electron microscope, fast-scanning and frame-averaging are two widely used approaches for reducing electron-beam damage and increasing image signal noise ratio which require no additional specialized hardware. Unfortunately, for scans with short pixel dwell-times (less than 5 μs), line flyback time represents an increasingly wasteful overhead. Although beam exposure during flyback causes damage while yielding no useful information, scan coil hysteresis means that eliminating it entirely leads to unacceptably distorted images. In this work, we reduce this flyback to an absolute minimum by calibrating and correcting for this hysteresis in postprocessing. Substantial improvements in dose efficiency can be realized (up to 20%), while crystallographic and spatial fidelity is maintained for displacement/strain measurement.

Many-body localization enables iterative quantum optimization

We suggest an iterative quantum protocol, allowing to solve optimization problems with a glassy energy landscape. It is based on a periodic cycling around the tricritical point of the many-body localization transition. This ensures that each iteration leads to a non-exponentially small probability to find a lower local energy minimum. The other key ingredient is to tailor the cycle parameters to a currently achieved optimal state (the "reference" state) and to reset them once a deeper minimum is found. We show that, if the position of the tricritical point is known, the algorithm allows to approach the absolute minimum with any given precision in a polynomial time.

Determination of the Variability of Bioactive Compounds and Minerals in Olive Leaf along an Agronomic Cycle

Olive leaves are still considered waste in the oil industry; however, the leaves have a content of oleuropein and other bioactive compounds that gives them great potential to be transformed into by-products. The most appropriate moment along an agronomic cycle (November 2019 to October 2020) has been evaluated to take advantage of this potential of the olive leaves varieties of Picual, Cornicabra and Manzanilla. In addition, factors that affect the content of phenolic compounds such as absolute maximum and minimum temperatures, relative humidity, sunshine hours, rainfall, differential of temperatures and mineral nutrition have been studied. The results show that the pruning season was the best time to take advantage of the olive leaf due to its high oleuropein content, especially in Picual and Manzanilla. The variety was the factor that most affected all the phenolic compounds studied, while the absolute minimum temperature factor notably affected verbascoside. Particular mineral nutrients, such as Mg and Fe, turned out to be most useful for differentiating locations. The content of verbascoside and hydroxytyrosol was also affected by agronomic conditions (location/conventional or ecological).

Shell Rounds the Corner on a Whale of a Task

Shell had a problem. It had just spent billions to bring its Appomattox find on line in the deepwater Gulf of Mexico (GOM). That development featured the oil giant’s eighth and largest floating platform in the region. The host semisubmersible weighed 125,000 metric tons—more than the largest aircraft carrier. Shell lauded its ability to reduce project cost by 40%, based on experience gained from the development of its previous four-column production platforms in the US Gulf, including the Olympus tension-leg platform. It would transfer these learnings to its next project—the Vito find in about 4,000 ft of water, 150 miles southeast of New Orleans. The field could hold up to 300 million BOE. At the same time the plans for Vito were being laid out, shale projects leapt to the forefront in the competition for capex dollars, and due to the comparative investment, they were winning. Industry success across the nation’s shale plays helped flood the market with oil, forcing the price per barrel down. Suddenly, spending big money on megaprojects offshore had lost much of its luster. For the US Gulf to reclaim at least some of its competitive advantage, fields could no longer be developed with massive, high-dollar facilities. A management mandate dictated that a new minimal, repeatable solution be found. After several years of study, a favorite emerged. “The original concept of Vito was much larger,” said Kurt Shallenberger, Vito project manager for Shell. “The development was probably similar in size to the Appomattox project that Shell recently completed—a 40,000-ton topsides, and a 50-year field life with a sizable gas-reinjection component to it.” Shell’s method for arriving at the new development scheme was dubbed “Minimal Technical Scoping”—the company would start with the absolute minimum scope and then justify additions upward. The project mantra was “Simpler is safer.” The results were a simplified topsides design as well as streamlined mooring systems for the host facility. “The redesign took it down to what I call the sweet spot of semisubmersibles—around a 10,000-ton deck,” said Shallenberger. “You had seen examples of that with LLOG’s Delta House, Independence Hub, and others like that. That was the sweet spot to where multiple fabricators can build it, multiple yards can integrate it, multiple companies can install it—and you can generally get 100,000 bbl a day through it. Now you’re in a competitive environment for all the vendors rather than just the one guy in the world who can do this. That’s what really created the opportunity for Vito. We shrunk the size and scope down to a point where it could get to a breakeven price that is competitive with the onshore folks.” According to Shell, the breakeven price for their minimal floater design is less than $35/bbl. Shell locked up key vendors for Vito. Jacobs Engineering Group carried out the detailed engineering and front-end engineering design studies for the Vito topsides. Sembcorp would build the host and integrate the topsides and hull at its Tuas Boulevard yard in Singapore.

Prerequisites for the effective fight against hate crimes

Hate crimes poison societies by threatening individual rights, human dignity and equality. They effect private lives, or even victims’ life and limb. Due to their ripple effect, they terrify whole communities, reinforce tensions between social groups, ultimately jeopardising peaceful coexistence. No society is immune from the signs of hatred, but whether they get tamed or whether prejudices are deepened, depends on the social measures that are applied vis-à-vis the phenomenon. The state’s reaction creates norms and will informs society about the current acceptable standards. European expectations help forming these. Standards developed by the European Court of Human Rights include the obligations to ensure that hate against social groups as a motivation is considered an aggravating circumstance or leads to penalty enhancement. States must also ensure that national investigation authorities show special vigilance to explore and unmask the bias motives behind hate crimes. Such European expectations still leave a wide room of manoeuvre to respond to hate crimes efficiently and dissuasively. But irrespectively of the national codification method, for legal provisions to reach the desired outcome, certain social preconditions must be met. For hate crime laws or provisions to work, states must reach a certain level of maturity from the viewpoint of democracy, fundamental rights in general and the rule of law, where guaranteeing judicial independence is an absolute minimum.

Spatiotemporal Analysis of the Frost Regime in the Iberian Peninsula in the Context of Climate Change (1975–2018)

Climate change is having many effects in the agricultural sector, which are being studied worldwide. Undoubtedly, warmer winters and earlier springs produce changes in frost regimes and severity that will affect the sustainability of agricultural production in the area. The Mediterranean region and the Iberian Peninsula (IP) are among the areas where the greatest impact of climate change is expected. Daily data from 68 weather stations of the IP belonging to the European Climate Assessment and Dataset (1975–2018) were used to conduct a spatiotemporal study of the frost regime. The variables calculated include the probability of three frost types according to their severity, frost day, mean absolute minimum yearly temperature, first frost day, last frost day, and frost-free period. These variables were integrated into a geographic information system, which allowed the graphical visualization of their patterns using of geostatistical interpolation techniques (kriging). Changes in frost variables were investigated using the Mann–Kendall test and Sen’s slope estimator. A general reduction in the number of frosts per year is observed (values between −0.04- and −0.8-day frosts per year), as well as an increase in the mean absolute minimum temperature (values between 0.04 and 0.10 °C per year), with very high significant trends throughout the territory. The reduction in the number of frosts is more pronounced at a higher elevation. Frost dates vary greatly due to the orographic characteristics of the IP. The generalized trend is of a significant delay of the autumn frosts (values between 0.4 and 1.06 days/year), as well as early spring frosts (between −0.429 and −1.29 days/year), and as a consequence a longer frost-free period, all changes were much stronger than those found in other regions of the world. These effects of climate change must be mitigated by modifying species, varieties, and cultivation techniques to guarantee sustainable agriculture.

Future trends in measuring physiology in free-living animals

Thus far, ecophysiology research has predominantly been conducted within controlled laboratory-based environments, owing to a mismatch between the recording technologies available for physiological monitoring in wild animals and the suite of behaviours and environments they need to withstand, without unduly affecting subjects. While it is possible to record some physiological variables for free-living animals using animal-attached logging devices, including inertial-measurement, heart-rate and temperature loggers, the field is still in its infancy. In this opinion piece, we review the most important future research directions for advancing the field of ‘physiologging’ in wild animals, including the technological development that we anticipate will be required, and the fiscal and ethical challenges that must be overcome. Non-invasive, multi-sensor miniature devices are ubiquitous in the world of human health and fitness monitoring, creating invaluable opportunities for animal and human physiologging to drive synergistic advances. We argue that by capitalizing on the research efforts and advancements made in the development of human wearables, it will be possible to design the non-invasive loggers needed by ecophysiologists to collect accurate physiological data from free-ranging animals ethically and with an absolute minimum of impact. In turn, findings have the capacity to foster transformative advances in human health monitoring. Thus, we invite biomedical engineers and researchers to collaborate with the animal-tagging community to drive forward the advancements necessary to realize the full potential of both fields. This article is part of the theme issue ‘Measuring physiology in free-living animals (Part II)’.

Getting It Straight: Accommodating Rectilinear Behavior in Captive Snakes—A Review of Recommendations and Their Evidence Base

Snakes are sentient animals and should be subject to the accepted general welfare principles of other species. However, they are also the only vertebrates commonly housed in conditions that prevent them from adopting rectilinear behavior (ability to fully stretch out). To assess the evidence bases for historical and current guidance on snake spatial considerations, we conducted a literature search and review regarding recommendations consistent with or specifying ≥1 × and <1 × snake length enclosure size. We identified 65 publications referring to snake enclosure sizes, which were separated into three categories: peer-reviewed literature (article or chapter appearing in a peer-reviewed journal or book, n = 31), grey literature (government or other report or scientific letter, n = 18), and opaque literature (non-scientifically indexed reports, care sheets, articles, husbandry books, website or other information for which originating source is not based on scientific evidence or where scientific evidence was not provided, n = 16). We found that recommendations suggesting enclosure sizes shorter than the snakes were based entirely on decades-old ‘rule of thumb’ practices that were unsupported by scientific evidence. In contrast, recommendations suggesting enclosure sizes that allowed snakes to fully stretch utilized scientific evidence and considerations of animal welfare. Providing snakes with enclosures that enable them to fully stretch does not suggest that so doing allows adequate space for all necessary normal and important considerations. However, such enclosures are vital to allow for a limited number of essential welfare-associated behaviors, of which rectilinear posturing is one, making them absolute minimum facilities even for short-term housing.

Understanding Molecular Clocks and Time Trees

This chapter examines molecular clocks and time trees. Although laden with numerous process assumptions that may or may not be true (or knowable), the idea is appealingly straightforward: if amino acid substitutions in proteins occurred at a relatively steady pace that were more or less constant both over time and along each of the branches of a diverging evolutionary tree, then the number of substitutions would be directly related to the time since the taxa in question diverged from one another. However, evidence does not support a universal molecular clock. Evidence might or might not support “local” clocklike evolution among closely related taxa over relatively short time spans. Although absolute minimum ages for clades may be inferred from fossils, from biogeographical patterns, or extrapolated from secondary calibrations, such age estimates are subject to potentially significant error due to vagaries of geological dating as well as ambiguities of fossil identity. The test of a time tree hypothesis is to discover new fossil evidence that corroborates or falsifies it.

Wildfire ash mobilization by splash under simulated rainfall in controlled laboratory conditions

&lt;p&gt;Recently burnt areas across the world have been documented to produce strong to extreme runoff and erosion responses. At the same time, they are well known to lose their typically blackish colour due to wildfire ashes (&lt;em&gt;sensu latu&lt;/em&gt;, including char) relatively quickly during the early phases of the window-of-disturbance. The contribution of wildfire ash to post-fire erosion rates, however, remains poorly quantified. Arguably, this is first and foremost due to the difficulties of separating the ash and char fractions from the mineral soil fractions, at least at the routinely basis that is required for field erosion studies with high temporal resolution (say, less than 1 month) and an absolute minimum of three replicate plots per slope or treatment. To this end, the national ASHMOB project (CENTRO-01-0145-FEDER-029351) is trying to advance the knowledge of the mobilization of wildfire ash by wind and water erosion by studying it first under controlled laboratory conditions. The present study concerns the first phase of wildfire ash erosion by water, using Morgan cups to quantify the splash erosion of wildfire ash by high-intensity simulated rainfall in the Laboratory of Hydraulics, Water Resources and Environment of the University of Coimbra. More specifically, this study assessed the importance of the following factors in ash splash erosion: (1) extreme rainfall intensities, ranging from 150 to 450 mm/h; (2) source of the ash, from recently burnt woodlands dominated by maritime &lt;em&gt;Pinus pinaster&lt;/em&gt;, &lt;em&gt;Eucalyptus globulus&lt;/em&gt;, and &lt;em&gt;Arbutus unedo&lt;/em&gt;; (3) ash depth or load. Preliminary analysis of the obtained results suggested that splash erosion of wildfire ash: (1) varied strongly with the applied rainfall intensity, increasing in a linear manner with increasing intensity; (2) differed markedly with the dominant tree cover, being clearly lower for the pine and eucalypt stands than for the strawberry tree stands, possibly due to the differences in soil burn severity as indicated by blackish and whitish ashes, respectively; (3) depended noticeably on ash depth, decreasing clearly with increasing ash depth and, arguably, with a greater damping capacity.&lt;/p&gt;