Analysis of the juvenile shell of Lingula anatina (Brachiopoda: Linguliformea) provides insight into the evolution of life cycles of fossil brachiopods

Paleobiology ◽  
2020 ◽  
pp. 1-15
Author(s):  
Anna A. Madison ◽  
Tatyana V. Kuzmina ◽  
Elena N. Temereva

Abstract Inferences on the development and morphology of extinct brachiopods must be informed by the ontogeny and shell ornamentation of extant brachiopods. Although the adult shells of extant brachiopods are well studied, detailed descriptions of the embryonic and juvenile shells of extant lingulides are lacking. Here, we describe in detail the shells of juveniles of Lingula anatina Lamarck, 1801 from Vietnam and the Republic of the Philippines. The following previously unknown properties of the lingulide shell are described: (1) a distinct border between the protegulum and the brephic shell; (2) drapes that develop on both the protegulum and brephic shell; and (3) the notched anterior margin of the brephic shell. The drapes and cogs on the brephic shell may be caused by the formation of setal follicles during the planktonic stage. Specimens of L. anatina from the Philippines have larger brephic shells than those from Vietnam, probably because the former have a longer planktonic stage. Based on comparisons of the first-formed shells of extant brachiopods with published data on fossil brachiopods, we suggest that the life cycle of extant lingulides, in which planktotrophic juveniles with a shell hatch from the egg envelope, is the most evolutionarily advanced brachiopod life cycle and appeared in the early Silurian. We suggest criteria for determining the type of life cycle based on the structure of the first-formed shell of brachiopods. Finally, we consider hypothetical scenarios of life cycles of fossil brachiopods, including true planktotrophic larvae in the Cambrian linguliforms.

2017 ◽  
Vol 114 (37) ◽  
pp. 9936-9941 ◽  
Author(s):  
Ronald M. Bonett ◽  
Andrea L. Blair

Metazoans display a tremendous diversity of developmental patterns, including complex life cycles composed of morphologically disparate stages. In this regard, the evolution of life cycle complexity promotes phenotypic diversity. However, correlations between life cycle stages can constrain the evolution of some structures and functions. Despite the potential macroevolutionary consequences, few studies have tested the impacts of life cycle evolution on broad-scale patterns of trait diversification. Here we show that larval and adult salamanders with a simple, aquatic-only (paedomorphic) life cycle had an increased rate of vertebral column and body form diversification compared to lineages with a complex, aquatic-terrestrial (biphasic) life cycle. These differences in life cycle complexity explain the variations in vertebral number and adult body form better than larval ecology. In addition, we found that lineages with a simple terrestrial-only (direct developing) life cycle also had a higher rate of adult body form evolution than biphasic lineages, but still 10-fold lower than aquatic-only lineages. Our analyses demonstrate that prominent shifts in phenotypic evolution can follow long-term transitions in life cycle complexity, which may reflect underlying stage-dependent constraints.


2020 ◽  
Vol 1 (10) ◽  
pp. 26-35
Author(s):  
E. A. SHUBINA ◽  
◽  
Yu. A. KOMAROVSKY ◽  
A. V. MERKUSHEV ◽  
◽  
...  

The article is devoted to the study of the largest mergers and acquisitions (M&A, “Mergers & Acquisitions”) in Russia for 2017–2019. (the acquired block of shares is not less than 99%). The concept of life cycles of organizations and theoretical aspects of mergers and acquisitions are described. The stages of the life cycle of the merged and reorganized companies, the goals of mergers and acquisitions, depending on the stages of the life cycle are analyzed.


Author(s):  
Valeriy S. Gerasimov ◽  
Vladimir I. Ignatov ◽  
Konstantin G. Sovin

According to forecasts for 2022, the number of self-propelled agricultural machinery that will fail will be about 100 thousand units. This will have a significant impact on the overall productivity in the field of agricultural production and will require additional financial costs for effective resource-saving environmental-oriented utilization of agricultural machinery with the maximum recovery of secondary resources in the processing of its components. (Research purpose) The research purpose is considering the main life cycles of machinery, including agricultural, and determining the possibility of obtaining secondary resources in the recycling of components of machinery and equipment. (Materials and methods) The authors found that the establishment of an industry-wide recycling system would allow the reuse of usable and recovered parts obtained from decommissioned equipment, as well as receive additional funding from the sale of secondary resources. The authors have found that for the functioning of the whole system, it is necessary to work with a large amount of data related to the ongoing recycling processes, as well as constantly monitor changes in the state and properties of materials. They also found that the maximum use of digital technology is the only way to combine all these requirements and make the system work. (Results and discussion) The article reviews the key points of the use of life cycle method for equipment, including agricultural, reviews the state of machine and tractor park of agro-industrial complex, shows the possibility of using resource-saving ecologically oriented branch system of recycling of agricultural machinery, as well as the movement of waste and material flows in the processing components of utilized machines. (Conclusion) The article presents recommendations on the possibility of efficient disposal of equipment, including agricultural, with the maximum recovery of secondary resources from recycled waste.


Author(s):  
Hannah Cornwell

This book examines the two generations that spanned the collapse of the Republic and the Augustan period to understand how the concept of pax Romana, as a central ideology of Roman imperialism, evolved. The author argues for the integral nature of pax in understanding the changing dynamics of the Roman state through civil war to the creation of a new political system and world-rule. The period of the late Republic to the early Principate involved changes in the notion of imperialism. This is the story of how peace acquired a central role within imperial discourse over the course of the collapse of the Republican framework to become deployed in the legitimization of the Augustan regime. It is an examination of the movement from the debates over the content of the concept, in the dying Republic, to the creation of an authorized version controlled by the princeps, through an examination of a series of conceptions about peace, culminating with the pax augusta as the first crystallization of an imperial concept of peace. Just as there existed not one but a series of ideas concerning Roman imperialism, so too were there numerous different meanings, applications, and contexts within which Romans talked about ‘peace’. Examining these different nuances allows us insight into the ways they understood power dynamics, and how these were contingent on the political structures of the day. Roman discourses on peace were part of the wider discussion on the way in which Rome conceptualized her Empire and ideas of imperialism.


2020 ◽  
Vol 40 (6) ◽  
pp. 825-832 ◽  
Author(s):  
Miku Yabuta ◽  
Jens T Høeg ◽  
Shigeyuki Yamato ◽  
Yoichi Yusa

Abstract Although parasitic castration is widespread among rhizocephalan barnacles, Boschmaella japonica Deichmann & Høeg, 1990 does not completely sterilise the host barnacle Chthamalus challengeri Hoek, 1883. As little information is available on the relationships with the host in “barnacle-infesting parasitic barnacles” (family Chthamalophilidae), we studied the life cycles of both B. japonica and C. challengeri and the effects of the parasite on the host reproduction. Specimens of C. challengeri were collected from an upper intertidal shore at Shirahama, Wakayama, western Japan from April 2017 to September 2018 at 1–3 mo intervals. We recorded the body size, number of eggs, egg volume, and the presence of the parasite for each host. Moreover, settlement and growth of C. challengeri were followed in two fixed quadrats. Chthamalus challengeri brooded from February to June. The prevalence of B. japonica was high (often exceeded 10%) from April to July, and was rarely observed from September to next spring. The life cycle of the parasite matched well with that of the host. The parasite reduced the host’s brooding rate and brood size, to the extent that no hosts brooded in 2018.


2021 ◽  
Vol 13 (10) ◽  
pp. 5726
Author(s):  
Aleksandra Wewer ◽  
Pinar Bilge ◽  
Franz Dietrich

Electromobility is a new approach to the reduction of CO2 emissions and the deceleration of global warming. Its environmental impacts are often compared to traditional mobility solutions based on gasoline or diesel engines. The comparison pertains mostly to the single life cycle of a battery. The impact of multiple life cycles remains an important, and yet unanswered, question. The aim of this paper is to demonstrate advances of 2nd life applications for lithium ion batteries from electric vehicles based on their energy demand. Therefore, it highlights the limitations of a conventional life cycle analysis (LCA) and presents a supplementary method of analysis by providing the design and results of a meta study on the environmental impact of lithium ion batteries. The study focuses on energy demand, and investigates its total impact for different cases considering 2nd life applications such as (C1) material recycling, (C2) repurposing and (C3) reuse. Required reprocessing methods such as remanufacturing of batteries lie at the basis of these 2nd life applications. Batteries are used in their 2nd lives for stationary energy storage (C2, repurpose) and electric vehicles (C3, reuse). The study results confirm that both of these 2nd life applications require less energy than the recycling of batteries at the end of their first life and the production of new batteries. The paper concludes by identifying future research areas in order to generate precise forecasts for 2nd life applications and their industrial dissemination.


Author(s):  
Svenja Heesch ◽  
Martha Serrano‐Serrano ◽  
Josué Barrera‐Redondo ◽  
Rémy Luthringer ◽  
Akira F. Peters ◽  
...  

2021 ◽  
Vol 13 (4) ◽  
pp. 1935
Author(s):  
Vitantonio Colucci ◽  
Giampaolo Manfrida ◽  
Barbara Mendecka ◽  
Lorenzo Talluri ◽  
Claudio Zuffi

This study deals with the life cycle assessment (LCA) and an exergo-environmental analysis (EEvA) of the geothermal Power Plant of Hellisheiði (Iceland), a combined heat and power double flash plant, with an installed power of 303.3 MW for electricity and 133 MW for hot water. LCA approach is used to evaluate and analyse the environmental performance at the power plant global level. A more in-depth study is developed, at the power plant components level, through EEvA. The analysis employs existing published data with a realignment of the inventory to the latest data resource and compares the life cycle impacts of three methods (ILCD 2011 Midpoint, ReCiPe 2016 Midpoint-Endpoint, and CML-IA Baseline) for two different scenarios. In scenario 1, any emission abatement system is considered. In scenario 2, re-injection of CO2 and H2S is accounted for. The analysis identifies some major hot spots for the environmental power plant impacts, like acidification, particulate matter formation, ecosystem, and human toxicity, mainly caused by some specific sources. Finally, an exergo-environmental analysis allows indicating the wells as significant contributors of the environmental impact rate associated with the construction, Operation & Maintenance, and end of life stages and the HP condenser as the component with the highest environmental cost rate.


2021 ◽  
Vol 42 (1) ◽  
pp. 111-126
Author(s):  
Cleves Nkie Mongo

This article provides insight into the “brown envelope journalism” in the Republic of the Congo (Brazzaville). Through in-depth interviews with journalists from four major Congolese news outlets, this research reveals how financial difficulties result in reporters justifying their violations of journalism ethics and standards. While two news outlets accept bribes to compensate for their precarious financial situation, two other news organizations pretend that they oppose envelope journalism although this research shows that their reporters also secretly accept bribes.


2021 ◽  
Vol 9 (4) ◽  
pp. 760
Author(s):  
Tatyana V. Butina ◽  
Yurij S. Bukin ◽  
Ivan S. Petrushin ◽  
Alexey E. Tupikin ◽  
Marsel R. Kabilov ◽  
...  

Lake Baikal is a unique oligotrophic freshwater lake with unusually cold conditions and amazing biological diversity. Studies of the lake’s viral communities have begun recently, and their full diversity is not elucidated yet. Here, we performed DNA viral metagenomic analysis on integral samples from four different deep-water and shallow stations of the southern and central basins of the lake. There was a strict distinction of viral communities in areas with different environmental conditions. Comparative analysis with other freshwater lakes revealed the highest similarity of Baikal viromes with those of the Asian lakes Soyang and Biwa. Analysis of new data, together with previously published data allowed us to get a deeper insight into the diversity and functional potential of Baikal viruses; however, the true diversity of Baikal viruses in the lake ecosystem remains still unknown. The new metaviromic data will be useful for future studies of viral composition, distribution, and the dynamics associated with global climatic and anthropogenic impacts on this ecosystem.


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