Studying migration over a long period is challenging due to lack of data, uneven data quality, and the methodological challenges that arise when analyzing migration over large geographic areas and ...long time spans with constantly changing political boundaries. Crowd-sourced family tree data are an untapped source of volunteered geographic information generated by millions of users. These trees contain information on individuals such as birth and death places and years, and kinship ties, and have the potential to support analysis of population dynamics and migration over many generations and far into the past. In this article, we introduce a methodology to measure and map long-term changes in migration flows using a population-scale family-tree data set. Our methodology includes many steps such as extracting migration events, temporal periodization, gravity normalization, and producing time-series flow maps. We study internal migration in the continental United States between 1789 and 1924 using birthplaces and birthyears of children from a cleaned, geocoded, and connected set of family trees from Rootsweb.com. To the best of our knowledge, the results are the first migration flow maps that show how the internal migration flows within the U.S. changed over such a long period of time (i.e. 135 years).
ABSTRACT
The whole‐body (tachymetabolic) endothermy seen in modern birds and mammals is long held to have evolved independently in each group, a reasonable assumption when it was believed that its ...earliest appearances in birds and mammals arose many millions of years apart. That assumption is consistent with current acceptance that the non‐shivering thermogenesis (NST) component of regulatory body heat originates differently in each group: from skeletal muscle in birds and from brown adipose tissue (BAT) in mammals. However, BAT is absent in monotremes, marsupials, and many eutherians, all whole‐body endotherms. Indeed, recent research implies that BAT‐driven NST originated more recently and that the biochemical processes driving muscle NST in birds, many modern mammals and the ancestors of both may be similar, deriving from controlled ‘slippage’ of Ca2+ from the sarcoplasmic reticulum Ca2+‐ATPase (SERCA) in skeletal muscle, similar to a process seen in some fishes. This similarity prompted our realisation that the capacity for whole‐body endothermy could even have pre‐dated the divergence of Amniota into Synapsida and Sauropsida, leading us to hypothesise the homology of whole‐body endothermy in birds and mammals, in contrast to the current assumption of their independent (convergent) evolution. To explore the extent of similarity between muscle NST in mammals and birds we undertook a detailed review of these processes and their control in each group. We found considerable but not complete similarity between them: in extant mammals the ‘slippage’ is controlled by the protein sarcolipin (SLN), in birds the SLN is slightly different structurally and its role in NST is not yet proved. However, considering the multi‐millions of years since the separation of synapsids and diapsids, we consider that the similarity between NST production in birds and mammals is consistent with their whole‐body endothermy being homologous. If so, we should expect to find evidence for it much earlier and more widespread among extinct amniotes than is currently recognised. Accordingly, we conducted an extensive survey of the palaeontological literature using established proxies. Fossil bone histology reveals evidence of sustained rapid growth rates indicating tachymetabolism. Large body size and erect stature indicate high systemic arterial blood pressures and four‐chambered hearts, characteristic of tachymetabolism. Large nutrient foramina in long bones are indicative of high bone perfusion for rapid somatic growth and for repair of microfractures caused by intense locomotion. Obligate bipedality appeared early and only in whole‐body endotherms. Isotopic profiles of fossil material indicate endothermic levels of body temperature. These proxies led us to compelling evidence for the widespread occurrence of whole‐body endothermy among numerous extinct synapsids and sauropsids, and very early in each clade's family tree. These results are consistent with and support our hypothesis that tachymetabolic endothermy is plesiomorphic in Amniota. A hypothetical structure for the heart of the earliest endothermic amniotes is proposed. We conclude that there is strong evidence for whole‐body endothermy being ancient and widespread among amniotes and that the similarity of biochemical processes driving muscle NST in extant birds and mammals strengthens the case for its plesiomorphy.
Abstract
We study the Pontus structure—a recently discovered merger that brought in ∼7 globular clusters in the course of the hierarchical buildup of the Milky Way’s halo. Here, we analyze the ...stellar population of Pontus and examine (1) its phase-space distribution using the ESA/Gaia data set, (2) its metallicity and chemical abundances (i.e., Fe/H,
α
/Fe, Mg/Fe, and Al/Fe) using the spectroscopic catalog of APOGEE DR17, and (3) the color–magnitude diagram that shows interesting features, including a possibly double horizontal branch and a small population of blue stragglers. In sum, the Pontus stars show some unique properties that suggest they likely originated from the merging of an independent satellite galaxy; however, future analysis will shed more light on the true nature of this structure. This chemodynamical analysis of Pontus stars is another step forward in our bigger quest to characterize all the merging events of our Milky Way.
Redox flow batteries (RFBs) are an increasingly attractive option for renewable energy storage, thus providing flexibility for the supply of electrical energy. In recent years, research in this type ...of battery storage has been shifted from metal-ion based electrolytes to soluble organic redox-active compounds. Aqueous-based organic electrolytes are considered as more promising electrolytes to achieve "green", safe, and low-cost energy storage. Many organic compounds and their derivatives have recently been intensively examined for application to redox flow batteries. This work presents an up-to-date overview of the redox organic compound groups tested for application in aqueous RFB. In the initial part, the most relevant requirements for technical electrolytes are described and discussed. The importance of supporting electrolytes selection, the limits for the aqueous system, and potential synthetic strategies for redox molecules are highlighted. The different organic redox couples described in the literature are grouped in a "family tree" for organic redox couples. This article is designed to be an introduction to the field of organic redox flow batteries and aims to provide an overview of current achievements as well as helping synthetic chemists to understand the basic concepts of the technical requirements for next-generation energy storage materials.
Despite the relative youth of our information systems discipline, many of us do not know the founders of our field or the academic “families” that have helped shape us into what we are today. We have ...changed greatly over the past few decades, both topically and geographically. As the Information Systems (IS) discipline enters its second half-century, now is a good time to identify the origins of our academic community while some of the founders are still with us. We have created a web-enabled “family tree” of more than 11 thousand IS scholars that investigators can use to examine where we came from, where we are going, and how we can position our field for future academic generations. The genealogical data can be used to show the trajectory of our research, the influences that shape our field, and the influences of organizational designs and the broader environment.
Recently, the enzyme family of oleate hydratases (OHs: EC 4.2.1.53) has gained increasing scientific and economic interest, as these FAD‐binding bacterial enzymes do not require cofactor recycling ...and possess high thermal and pH stability. Their products, hydroxy fatty acids, are used in specialty chemical applications including surfactant and lubricant formulations. The “oleate hydratase engineering database”, established by Schmid et al. (2017), divides all OHs into 11 families (HFam1 to 11). To date, only two crystal structures of homodimeric OHs from the families HFam2 and HFam11 have been reported. In this study, we biophysically characterized an OH belonging to the HFam3 family, originating from the marine bacterium Rhodococcus erythropolis, for the first time. The crystal structure revealed that this new OH (OhyRe) surprisingly is a monomer in its active form. This particular feature provides new avenues for enzyme engineering and recycling through immobilization.
Genome mining: Oleate hydratase belonging to the HFam3 family, originating from the marine bacterium Rhodococcus erythropolis, is biophysically characterized for the first time. The crystal structure revealed that this new OH (OhyRe) surprisingly is a monomer in its active form. This particular feature provides new avenues for enzyme engineering and recycling through immobilization.
Seed for thought Soltis, Douglas E
Nature (London),
06/2021, Letnik:
594, Številka:
7862
Journal Article
Recenzirano
The fossil record contains many clades of now-extinct gymnosperms, and it is not clear which group gave rise to the angiosperms, although it is definitely not one of the living groups of gymnosperms ...- plants such as conifers, ginkgo (Ginkgo bitoba) or cycads2,3. Amazingly, these are not recently discovered fossil specimens; they were collected almost a century ago, deposited in museum collections and only recently unearthed for a second time (this time, from museum drawers by the authors), with their relevance for reconstructing the plant family tree now finally recognized. Similar cupule-bearing fossils are much older - including Caytonia, a fossil gymnosperm whose discovery first raised the possibility that similar extinct plants with cupules and seeds were close relatives, or even ancestors, of flowering plants2,3.
SARS-CoV-2-watchers are tracking an unprecedented menagerie of variants from a number of branches of the Omicron family tree, says Tom Peacock, a virologist at Imperial College London. Despite these ...variants' distinct ancestries, they share many mutations in the SARS-CoV-2 spike protein (the part of the virus that immune systems target). All the variants that researchers are tracking contain multiple overlapping changes to a portion of the spike protein called the receptor binding domain, which is targeted by potent infection-blocking, or neutralizing, antibodies.
Our understanding of prehistoric societal organization at the family level is still limited. Here, we generated genome data from 32 individuals from an approximately 3,800-y-old burial mound ...attributed to the Bronze Age Srubnaya-Alakul cultural tradition at the site of Nepluyevsky, located in the Southern Ural region of Central Eurasia. We found that life expectancy was generally very low, with adult males living on average 8 y longer than females. A total of 35 first-degree, 40 second-degree, and 48 third-degree biological relationships connected 23 of the studied individuals, allowing us to propose a family tree spanning three generations with six brothers at its center. The oldest of these brothers had eight children with two women and the most children overall, whereas the other relationships were monogamous. Notably, related female children above the age of five were completely absent from the site, and adult females were more genetically diverse than males. These results suggest that biological relationships between male siblings played a structural role in society and that descent group membership was based on patrilineality. Women originated from a larger mating network and moved to join the men, with whom they were buried. Finally, the oldest brother likely held a higher social position, which was expressed in terms of fertility.
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