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In the midst of the COVID-19 pandemic, David Beasley, the Head of the World Food Programme, in his address to the Security Council of the United Nations (henceforth, the ‘UN’) stated that the world had to “act fast” to avoid “multiple famines of biblical proportions within a short few months”. While the UN feared that severe global food shortages would strike many parts of the world, prices for corn, wheat and soybeans have not increased in response to the spike in demand caused by the onset of the pandemic. Instead, the most active corn futures on the Chicago Board of Trade (henceforth, the ‘CBOT’), which is the world’s most important commodity exchange, have fallen by 16% since the start of 2020, while wheat has fallen by nearly 6% and soybeans by nearly 5%. Farmers are the ones who are losing profits. For instance, in the US, 8% more farmers filed for bankruptcy in 2020, than in the first half of 2019, and this number has been steadily increasing for the past 5 years. Across Africa, millions of farmers are facing economic devastation as the crop prices offered to them continue to fall and, in some cases, amount to less than the farmers’ production costs. In Eurasia, particularly in Russia and Ukraine, farmers have been seriously impacted by the pandemic as well. This issue of farmers being subject to profit losses has been witnessed across the world, but there is no systemic change to their desperate economic situations on the horizon.
In this paper, we compile estimates of cod size distributions based on zooarchaeological data and contemporary length-frequency data to look at variability in size composition through time across the North Pacific, from the northern Kuril Islands through the Aleutian Islands to southeast Alaska. The results suggest that a strong longitudinal trend in cod size has remained consistent over time, with the largest cod found to the west. We find that five of nine sites show that overall cod length and distribution of the largest fish remain relatively unchanged. Two sites where we find truncation of the length distributions—or loss of the largest fish—are places where the modern fisheries have the longest history and have been most intense, suggesting a potential for anthropogenic impacts on these local populations. We acknowledge two limitations in these data: (1) there are differences in selectivity between the ancient and modern fisheries; and (2) seasonal variability in fish availability was observed to be an important explanatory variable in the modern data set, but the season of harvest is poorly understood for the ancient collections. Therefore, while differences observed between the two data sets suggest possible anthropogenic influence on the size structure of Pacific cod, they are not conclusive.
Age and growth of blue antimora Antimora rostrata were examined for the first time in the waters of Kerguelen and Crozet Islands (southern Indian Ocean, sub-Antarctic). The longline catches were represented by fish ranging from 39 to 72 cm in total length with weights between 400 and 3310 g, aged 16– 41 years. A minimum age of 16 years was observed in a fish 39 cm long, while a maximum age of 41 years was recorded for an individual of 70 cm in length and 3310 g in weight. The age classes with the greatest numbers were represented by fish aged 34 years (9%), 28 years (9%) and 29 years (8%), which together accounted for 26% of the total catch. The blue antimora in the southern Indian Ocean shows similar growth rates to those of individual fish from the Ross, Lazarev and Weddell Seas and southeastern Greenland, which may indicate the population unity of the species within the Antarctic and sub-Antarctic waters or similar habitat conditions in these areas.
We propose three calibration scenarios of to date contemporary divergence of Anoplopomatidae (skilfish Erilepis zonifer and sablefish Anoplopoma fimbria) for a data set of two mtDNA loci (СOI and Control Region). The first scenario is based upon a fossil record and the second and third ones upon major palaeogeological events 3.5 and 15 Mya. Estimated evolution speeds indicate that COI evolves faster in the skilfish mitochondrial genome. There is also evidence of skilfish going through a bottleneck event limiting its genetic diversity in the relatively recent past near Japan. Sablefish had two refugia on both sides of the Pacific Ocean. The contemporary haplotype divergence was formed ~450 thousand years ago during an ice age in the Pleistocene and contemporary populations display no apparent geographic differentiation.
For the first time, the results of the study of the age and growth of blue hake Antimora rostrata in the waters of the Lazarev and Weddell seas (Antarctic) are presented. The longline catches were represented by fish from 42 to 69 cm in total length with weights between 420 and 2,900 g, and most individuals aged 25 to 27 years. A minimum age of 16 years was observed in a fish 47 cm long and weighing 450 g, while a maximum age of 35 years was recorded for an individual of 69 cm in length and 1,640 g in weight. The blue hake in the Lazarev and Weddell seas shows similar growth patterns to the fish from the Ross Sea and waters off Greenland.
Magnetic computing – in the broadest sense – is about using magnetic signals (nanomagnets, domain walls) to represent and process information. Nowadays, when “information processing” and “electronics” is synonymous, this concept sounds rather exotic. However, before the triumphant era of CMOS logic devices, non-charge based computers were serious candidates for information processing – for example, ingenious magnetic computing circuits were invented by R. J. Spain [1–3]. It was Cowburn [4] who first realized that the properties of nanoscale, single-domain magnets – which are very different from large, multi-domain magnets – are well suited for digital computing.
This chapter deals with one approach to magnetic computing, nanomagnet logic (or NML) [5, 6]. In NML devices, binary information is represented by the state (magnetization direction) of single domain nanomagnets and the magnetically represented information is propagated and processed by magnetic dipole–dipole interactions. From the circuit architecture point of view, NML builds on the concept of “quantum-dot cellular automata” [7] – they both share the idea of representing binary signals by bistable nanosystems and processing them through field-interactions. For this reason, nanomagnet logic was formerly called “magnetic quantum-dot cellular automata” (QCA), or field-coupled computing.
We consider smooth algebraic varieties with ample either canonical or anticanonical sheaf. We prove that such a variety is uniquely determined by its derived category of coherent sheaves. We also calculate the group of exact autoequivalences for these categories. The technics of ample sequences in Abelian categories is used.
An overview is given of the quantum-dot cellular automata (QCA) architecture, along with a summary of experimental demonstrations of QCA devices. QCA is a transistorless computation paradigm that can provide a solution to such challenging issues as device and power density. The basic building blocks of the QCA architecture, such as AND, OR gates and clocked cells have been demonstrated and will be presented here. The quantum dots used in the experiments to date are metal islands that are coupled by capacitors and tunnel junctions, and devices operate only at very low temperatures. For QCA to be used in practical devices, the operating temperature must be raised, and issues such as background charge must be addressed. An introduction will be given to these issues and possible solutions.
Two methods are proposed for describing the distributions of the triplet configuration parameters characterizing a tendency to alignment and hierarchy: (1) obtaining a representative sample of configurations and determining its statistical parameters (moments and percentages); and (2) dividing the region of possible configurations of triple systems (Agekian and Anosova, 1967) into a set of segments and finding the probabilities for the configurations to find themselves in each of them.
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