LIFE CYCLES IN ARTHROBACTER PASCENS AND ARTHROBACTER TERREGENS

1957 ◽  
Vol 3 (2) ◽  
pp. 103-106 ◽  
Author(s):  
C. E. Chaplin
Keyword(s):  
Life Cycle ◽  
Cell Division ◽  
Normal Cell ◽  
Type Species ◽  
Life Cycles ◽  
The Other ◽  
Soil Organisms ◽  
Free Cells ◽  
Growth Promoting ◽  
Pass Through

Two soil organisms, Arthrobacter pascens and Arthrobacter terregens, the first producing a growth-promoting substance, the "terregens factor", and the second requiring it, pass through a complex morphological life cycle. Two kinds of aged cells are found of which, on transfer to fresh medium, one forms a cystite which 'germinates' and looses free cells from a ruptured tube, the other follows the usual course of 'normal' cell division. The similarity in form to that of the type species Arthrobacter globiforme is quite distinct.

scholarly journals A New Species of Ligyrocoris Stal With a Key to the Northeastern Species (Hemiptera:Lygaeidae)

1963 ◽  
Vol 70 (1) ◽  
pp. 17-21
Author(s):  
Merrill H. Sweet
Keyword(s):  
New Species ◽  
Life Cycle ◽  
New England ◽  
Related Species ◽  
Habitat Preferences ◽  
Life Cycles ◽  
The Other ◽  
Closely Related Species ◽  
Carex Stricta ◽  
A New Species

In the course of current work upon the biology and ecology of the Rhyparochrominae of New England, a new species of Ligyrocoris was discovered. The species runs in Barber's (1921) key to the couplet separating diffusus (Uhler) from sylvestris (L.), but is distinct from either species. While the new species is closely related to these species, it is also quite close to L. depictus which is separated out in a different part of Barber's key.These four closely related species are sympatric in New England, although they are markedly different in their overall distribution. The habitat preferences and life cycles of the species are quite different (Sweet, unpublished). The habitat of the new species described below is most unusual for the genus. The greater part of the type series was collected along the margin of a small pond where sedge clumps were standing in the water among occasional exposed rocks rather than in relatively dry fields or slope habitats where the other species occur. The species feeds upon the seeds of the sedge, Carex stricta Lam, and its life cycle is apparently adapted to that of the sedge, which fruits in late May and June. The insect becomes adult in mid-June and lays eggs until mid-July. The eggs remain in diapause over the summer and winter and hatch in May.

Meiosis in perspective

1977 ◽  
Vol 277 (955) ◽  
pp. 185-189 ◽  
Keyword(s):  
Life Cycle ◽  
Natural Selection ◽  
Natural Variation ◽  
Higher Plants ◽  
Genetic Recombination ◽  
Genetic System ◽  
Life Cycles ◽  
The Other ◽  
Breeding Method ◽  
Physical And Chemical

Our understanding of meiosis springs from two suggestions made by Weismann in 1887. One was that meiosis would be found to compensate for fertilization in the life cycles of both sexes and all organisms. The other was that the development of sexual reproduction in evolution depended on the value of meiosis in exposing the results of genetic recombination to natural selection. In confirming these propositions we were bound to discover that the properties of meiosis appear both as the causes and the consequences of evolution: it is the hinge on which turns the evolution of breeding method, reproductive habit, life cycle and hereditary structure, that is the genetic system, in all sexually reproducing species of organism. We have had three main fields of attack on our problem. First, there was the natural variation of meiosis including that of two-track heredity within the species: here, animals took the lead. Secondly, there was the experimental field - both with genetic controls such as polyploidy and the sterilizing mutations of mitosis as well as meiosis, and with physical and chemical controls : here, the higher plants and microorganisms have given us our great opportunities. Thirdly, we have the widening field where physicochemical knowledge and genetic control converge and collaborate. In all this work we have to be aware that meiosis works with chromosomes which always have the two functions of accomplishing evolution and of implementing its results in heredity. In consequence, the adaptation of meiosis is perpetually imperfect.

scholarly journals Description of coccoid cyanoprokaryote Nisada stipitata morphogen. et sp. nov. from the supralittoral zone in the tropical Mexican Pacific

Phytotaxa ◽  
2015 ◽  
Vol 220 (3) ◽  
pp. 268 ◽  
Author(s):  
Michele Louise Gold ◽  
Laura González-Resendiz ◽  
Hilda León-Tejera ◽  
Gustavo Montejano
Keyword(s):  
Life Cycle ◽  
Type Species ◽  
Morphological Characteristics ◽  
The Other ◽  
Polyphasic Approach ◽  
Rocky Shores ◽  
Unique Combination ◽  
Mexican Pacific ◽  
Multiple Fission ◽  
Mexican Populations

A distinctive morphotype consisting of an epilithic, one-layered colony of polarized, 1–3-celled pseudofilaments was recognized in the rocky shores of the state of Oaxaca in the Mexican tropical Pacific. Morphologically, it was not identifiable as any species of a previously described genus. It is similar to species from the former order Chroococcales, recently modified by Komárek et al. (2014), in its sessile heteropolar pseudofilaments. Specifically, it is most similar to the colonial species of the genus Chamaesiphon; and of Chamaecalyx, but the cells of the Mexican populations divide symmetrically in one or two planes, differentiating them from Chamaesiphon which divides asymmetrically and only in one plane, and from Chamaecalyx, which has multiple fission. The other defining feature is that all cells of the pseudofilament have differentiated mucilaginous structures (pad and/or stipe and cup). It has not been possible to obtain cultures of our material for further studies to complete the polyphasic approach. Nevertheless, its morphological characteristics and life cycle, plus its distinctive extreme biotope, form a unique combination of features that derive in our proposal of the morphogenus Nisada gen. nov., with the type species, Nisada stipitata, sp. nov. We describe the proposed taxa and the problems and current inconveniences regarding its assignment to higher taxonomic levels. We also discuss the different degrees of complexity of heteropolarity in Nisada and other taxa.

The occurrence of Pneumocystis carinii in mice in England

Parasitology ◽  
1916 ◽  
Vol 8 (3) ◽  
pp. 255-259 ◽  
Author(s):  
Annie Porter
Keyword(s):  
Life Cycle ◽  
Pneumocystis Carinii ◽  
Scientific Progress ◽  
Life Cycles ◽  
The Other ◽  
Mixed Infections ◽  
Source Of Error ◽  
Little Owl ◽  
The Way

A fertile source of error in protozoology is to be found in the overlooking of the occurrence of mixed infections in a host. Two organisms, each independent of the other, may happen to coexist in the intestine of an insect or the blood of a vertebrate, the result being that the investigator may confuse stages in the life-cycles of parasites which are not related to each other. This source of error has led to unwarranted generalisations which have impeded scientific progress for years. Two examples at once come to mind—the trouble wrought by Schaudinn in 1904 in confusing the life-cycles of the protozoa found in the little owl, and the impediment put in the way of progress by the omission of certain workers to recognise that Crithidia grayi was not a part of the life-cycle of a trypanosome. The existence of mixed infections was overlooked in each case.

Stimulated Virus Production in Vinblastine and Cytochalasin-Induced Multinucleate Cells

1970 ◽  
Vol 28 ◽  
pp. 186-187
Author(s):  
Krishan Awtar
Keyword(s):  
Cell Division ◽  
Normal Cell ◽  
Virus Production ◽  
Multinucleate Cells ◽  
Daughter Cells ◽  
Cell Divisions ◽  
Nuclear Membranes ◽  
Division 2 ◽  
Vinblastine Sulfate

Exposure of cells to low sublethal but mitosis-arresting doses of vinblastine sulfate (Velban) results in the initial arrest of cells in mitosis followed by their subsequent return to an “interphase“-like stage. A large number of these cells reform their nuclear membranes and form large multimicronucleated cells, some containing as many as 25 or more micronuclei (1). Formation of large multinucleate cells is also caused by cytochalasin, by causing the fusion of daughter cells at the end of an otherwise .normal cell division (2). By the repetition of this process through subsequent cell divisions, large cells with 6 or more nuclei are formed.

MERGERS AND ACQUISITIONS AND THEIR CORRELATION WITH THE LIFE CYCLES OF MEMBER COMPANIES ON THE EXAMPLE OF THE RUSSIAN MARKET 2017–2019

2020 ◽  
Vol 1 (10) ◽  
pp. 26-35
Author(s):  
E. A. SHUBINA ◽  
◽  
Yu. A. KOMAROVSKY ◽  
A. V. MERKUSHEV ◽  
◽  
...  
Keyword(s):  
Life Cycle ◽  
Mergers And Acquisitions ◽  
Life Cycles ◽  
Russian Market

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.

State of Fashion: Searching for the New Luxury

APRIA Journal ◽  
2020 ◽  
Vol 1 (1) ◽  
pp. 11-16
Author(s):  
José Teunissen
Keyword(s):  
Twentieth Century ◽  
Daily Life ◽  
Life Cycles ◽  
The Other ◽  
Century Model ◽  
Cocktail Party ◽  
The Public ◽  
Other Hand ◽  
The One

In the last few years, it has often been said that the current fashion system is outdated, still operating by a twentieth-century model that celebrates the individualism of the 'star designer'. In I- D, Sarah Mower recently stated that for the last twenty years, fashion has been at a cocktail party and has completely lost any connection with the public and daily life. On the one hand, designers and big brands experience the enormous pressure to produce new collections at an ever higher pace, leaving less room for reflection, contemplation, and innovation. On the other hand, there is the continuous race to produce at even lower costs and implement more rapid life cycles, resulting in disastrous consequences for society and the environment.

Life cycle of self-propelled machinery with waste generation at its disposal

2020 ◽  
pp. 28-35
Author(s):  
Valeriy S. Gerasimov ◽  
Vladimir I. Ignatov ◽  
Konstantin G. Sovin
Keyword(s):  
Life Cycle ◽  
Life Cycles ◽  
The State ◽  
Research Purpose ◽  
Industrial Complex ◽  
Agricultural Machinery ◽  
Resource Saving ◽  
Secondary Resources ◽  
Branch System ◽  
Additional Funding

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.

Life cycles of the rhizocephalan Boschmaella japonica Deichmann & Høeg, 1990 (Cirripedia: Chthamalophilidae) and its host barnacle Chthamalus challengeri Hoek, 1883 (Cirripedia: Chthamalidae)

2020 ◽  
Vol 40 (6) ◽  
pp. 825-832 ◽  
Author(s):  
Miku Yabuta ◽  
Jens T Høeg ◽  
Shigeyuki Yamato ◽  
Yoichi Yusa
Keyword(s):  
Life Cycle ◽  
Brood Size ◽  
Life Cycles ◽  
The Body ◽  
Egg Volume ◽  
Size Number ◽  
Rhizocephalan Barnacles ◽  
Western Japan ◽  
Upper Intertidal ◽  
Chthamalus Challengeri

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.

scholarly journals Advances of 2nd Life Applications for Lithium Ion Batteries from Electric Vehicles Based on Energy Demand

2021 ◽  
Vol 13 (10) ◽  
pp. 5726
Author(s):  
Aleksandra Wewer ◽  
Pinar Bilge ◽  
Franz Dietrich
Keyword(s):  
Life Cycle ◽  
Lithium Ion Batteries ◽  
Electric Vehicles ◽  
Energy Demand ◽  
Lithium Ion ◽  
Life Cycles ◽  
Future Research ◽  
Research Areas ◽  
Study Results ◽  
The Impact

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.

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