scholarly journals Catostylus tagi (Class: Scyphozoa, Order: Discomedusae, Suborder: Rhizostomida, Family: Catostylidae) life cycle and first insight into its ecology

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12056
Author(s):  
Sonia K.M. Gueroun ◽  
Tatiana M. Torres ◽  
Antonina Dos Santos ◽  
Nuno Vasco-Rodrigues ◽  
João Canning-Clode ◽  
...  
Keyword(s):  
Life Cycle ◽  
Developmental Stages ◽  
Anthropogenic Activities ◽  
Total Body Length ◽  
Effect Of Temperature ◽  
Ecosystem Structure ◽  
Full Life Cycle ◽  
Wide Range ◽  
Key Factor ◽  
Total Body

Jellyfish proliferations, which are conspicuous and natural events, cause blooms that may lead to severe consequences for anthropogenic activities and ecosystem structure and functioning. Although research during the last decade has focused on factors influencing the different jellyfish life stages, few species currently have their full life cycle known. In this context, we describe for the first time the developmental stages in the life cycle of Catostylus tagi, from planula to young medusa, reared in the laboratory. The species displays the typical Rhizostomida metagenetic life cycle. Mature scyphistomae display 16 tentacles and a total body length of 1.5 ± 0.2 mm. Only podocyst production and strobilation were observed. Strobilation, occurring continuously under laboratory conditions, was mainly polydisc. The eight-rayed typical ephyrae, with a total body diameter of 2.4 ± 0.4 mm at detachment, showed development typical of the Rhizostomida. As a first step in studying this species’ ecology, we also present preliminary assessments of: (i) the influence of different temperature and salinity regimes on planulae survival, settlement and metamorphosis and (ii) the effect of temperature and diet on asexual reproduction. The results showed a high tolerance of planulae to a wide range of salinities (15‰ to 25‰), while polyp development was significantly faster at higher temperature (20–25 °C). Strobilation onset was 2–3 times faster at 20 °C (10.6 ± 5.4 to 15 ± 6.6 day at various tested diet) than at 15 °C (32.2 ± 3 day). Feeding was a key factor as unfed polyps never underwent strobilation during the trial. Finally, we present the spatial and seasonal distribution of C. tagi in the Tagus estuary (Portugal) in 2019, showing its occurrence throughout the year (except in April), with most observations recorded on the northern shoreline. As C. tagi shows the ability to form blooms and a wide tolerance for temperature and salinity (for planulae and medusae stage), it is essential to understand its life cycle.

A Data Model for Integration of the Precommissioning Life-Cycle Stages of the Shipbuilding Product

1992 ◽  
Vol 8 (04) ◽  
pp. 220-234
Author(s):  
M. Welsh ◽  
J. Lynch ◽  
P. Brun
Keyword(s):  
Life Cycle ◽  
Research Program ◽  
Product Life Cycle ◽  
Data Exchange ◽  
Product Model ◽  
Product Life ◽  
Related Data ◽  
Full Life Cycle ◽  
Wide Range ◽  
Neutral Product

This paper reports some aspects of the work being carried out on the NEUTRABAS project under the ESPRIT II European research program. The aim of this project is to specify and implement a neutral product definition database for large marine-related artifacts, covering a large part of the complete product life-cycle. The results of this research program will facilitate the effective exchange of product related data between disparate computer-based information systems, and hence promote a movement towards product life-cycle integration. The scope of the product model being developed as the basis for this integration is described in terms of its spatial and steel structural components, together with the implications for integration with other models of outfitting and engineering systems. The model is shown to encompass the wide range of product-related data which is associated with the various precommissioning stages of the product life-cycle. A suitable database architecture designed to support product data exchange and full life-cycle integration based on this product model is described and discussed.

scholarly journals The Morphological Characters of Egg and Relationship of Immature Stages of Hermolaus modestus (Heteroptera: Pentatomidae: Eysarcorini)

2021 ◽  
Vol 64 (1) ◽  
pp. 7-12
Author(s):  
Syed Ikhlaq Hussain ◽  
Muhammad Zahid ◽  
Haq Nawaz Abbasi ◽  
Fatima Hayat Shaheen Zafar
Keyword(s):  
Developmental Stages ◽  
Total Body Length ◽  
Ventral Side ◽  
Morphological Characters ◽  
Plant Leaves ◽  
Scent Gland ◽  
First Instar ◽  
Total Body ◽  
Relationship Of ◽  
Total Life

The paper investigates the biology and structure of egg and different developmental stages from 1st instar to 5th instar of Hermolaus modestus (Distant) (Pentatomidae: Eysarcorini). The experiment was conducted in the laboratory and the species was recognized as plant-sucking pest and mostly recorded on Ocimum basilicum (L.) from different areas of Karachi, Pakistan. The male and female individuals were breed under controlled laboratory condition. The maximum fertility range of Hermolaus modestus was observed 10 to 14 eggs per female and eggs were laid singly on the ventral side of plant leaves near the midrib. The incubation period was completed in 4 to 5 days. Newly emerged nymphs were dark red in colour but later colour changed into brown. The nymph passed through five instars progressively to complete the nymphal period. The first instar completed in 2 to 3 days with its specific characters. The second instar took 6 to 7 days with large clypeus. The third instar having scent gland plates and wing pads, completed in 5 to 6 days. The fourth and fifth instars of H. modestus completed in 5 to 6 and 8 to 9 days with prominent mesonotal and metanotal wing pads, respectively. The total nymphal period varied from 26 to 31 days. The total life cycle showed variation from 30 to 36 days. The total body length of male Hermolaus modestus was recorded as 4.8 mm to 5.0 mm.    

Life Cycle Prediction and Evaluation of Clutch Friction Plate Considering Wear Models and Thermal Stress

2020 ◽  
Vol 143 (4) ◽  
Author(s):  
Mengyu Zhu ◽  
Xintian Liu ◽  
Fuchao Kan ◽  
Ziyun You
Keyword(s):  
Life Cycle ◽  
Friction Surface ◽  
Sliding Friction ◽  
Contact Model ◽  
Effect Of Temperature ◽  
Body Model ◽  
Full Life Cycle ◽  
Influence Of Temperature On ◽  
Friction Plate ◽  
Work Model

Abstract To predict the life of the clutch friction plate, friction characteristics of the friction plate and the steel sheet assembly are analyzed in the full life cycle. A contact model of the friction surface is built based on the micro-convex body model. Wear mathematical models of friction plate are established respectively based on the contact model and sliding friction work model. The wear results of the two models are compared and analyzed. The effect of temperature on wear is considered. Fatigue life of the friction plate is predicted by wear mathematical model according to the real working states. The accuracy of the contact model and the influence of temperature on the wear are determined through the comparative analysis of each prediction result.

scholarly journals Influence of the Composition on the Environmental Impact of Soft Ferrites

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 1789
Author(s):  
Patricia Gómez ◽  
Daniel Elduque ◽  
Carmelo Pina ◽  
Carlos Javierre
Keyword(s):  
Life Cycle ◽  
Environmental Impact ◽  
Point Of View ◽  
Nickel Zinc ◽  
Manganese Zinc ◽  
Wide Range ◽  
Key Factor ◽  
Broad Variety ◽  
Scientists And Engineers ◽  
Soft Ferrites

The aim of this paper is to analyze the influence of the composition on the environmental impact of the two main types of soft ferrites, allowing scientists and engineers to compare them based not only on cost and properties, but also on an environmental point of view. Iron oxides are the basis of soft ferrites, but these ferrites have a wide range of compositions, using materials such as manganese or nickel, which affect their magnetic properties, but also modify the environmental impact. A Life Cycle Assessment has been carried out for manganese‒zinc (MnZn) and nickel‒zinc (NiZn) soft ferrites, with a Monte Carlo approach to assess multiple compositions. The LCA model was developed with SimaPro 8.4, using the EcoInvent v3.4 life cycle inventory database. Environmental impact values were calculated under the ReCiPe and Carbon Footprint methodologies, obtaining a broad variety of results depending on the composition. The results were also significantly different from the standard EcoInvent ferrite. For the analyzed soft ferrites, the presence of manganese or nickel is a key factor from an environmental perspective, as these materials involve high environmental impacts, and their supply risk has increased during recent years, making them a concern for European manufacturers.

scholarly journals Graphene-Based Nanomaterials in Soil: Ecotoxicity Assessment Using Enchytraeus crypticus Reduced Full Life Cycle

Nanomaterials ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 858 ◽  
Author(s):  
Monique C. P. Mendonça ◽  
Natália P. Rodrigues ◽  
Marcelo B. de Jesus ◽  
Mónica J. B. Amorim
Keyword(s):  
Graphene Oxide ◽  
Life Cycle ◽  
Soil Invertebrate ◽  
Reproduction Rate ◽  
Terrestrial Environment ◽  
Factors Affecting ◽  
Full Life Cycle ◽  
Wide Range ◽  
Enchytraeus Crypticus ◽  
Full Life

Graphene-based nanomaterials (GBNs) possess unique physicochemical properties, allowing a wide range of applications in physical, chemical, and biomedical fields. Although GBNs are broadly used, information about their adverse effects on ecosystem health, especially in the terrestrial environment, is limited. Therefore, this study aims to assess the toxicity of two commonly used derivatives of GBNs, graphene oxide (GO) and reduced graphene oxide (rGO), in the soil invertebrate Enchytraeus crypticus using a reduced full life cycle test. At higher exposure concentrations, GO induced high mortality and severe impairment in the reproduction rate, while rGO showed little adverse effect up to 1000 mg/kg. Collectively, our body of results suggests that the degree of oxidation of GO correlates with their toxic effects on E. crypticus, which argues against generalization on GBNs ecotoxicity. Identifying the key factors affecting the toxicity of GBNs, including ecotoxicity, is urgent for the design of safe GBNs for commercial purposes.

scholarly journals Ecological Function of Phenolic Compounds from Mediterranean Fucoid Algae and Seagrasses: An Overview on the Genus Cystoseira sensu lato and Posidonia oceanica (L.) Delile

2020 ◽  
Vol 8 (1) ◽  
pp. 19 ◽  
Author(s):  
Anna Maria Mannino ◽  
Carla Micheli
Keyword(s):  
Phenolic Compounds ◽  
Human Impacts ◽  
Anthropogenic Activities ◽  
Spatial Scales ◽  
Posidonia Oceanica ◽  
Ecosystem Structure ◽  
Anthropogenic Pressures ◽  
Industrial Sectors ◽  
Wide Range ◽  
Fucoid Algae

Biodiversity is undergoing rapid and worrying changes, partially driven by anthropogenic activities. Human impacts and climate change (e.g., increasing temperature and ocean acidification), which act at different spatial scales, represent the most serious threats to biodiversity and ecosystem structure and function. In the Mediterranean Sea, complex systems such as fucoid algae and seagrasses, characterized by a high associated biodiversity, are regularly exposed to natural and anthropogenic pressures. These systems, particularly sensitive to a variety of stressors, evolved several physiological and biochemical traits as a response to the different pressures which they are subjected to. For instance, they produce a huge quantity of secondary metabolites such as phenolic compounds, to adapt to different environmental stressors and to defend themselves from biological pressures. These natural products are receiving increasing attention due to their possible applications in a wide range of industrial sectors. In this paper we provide an overview on the ecological role of phenolic compounds from the genus Cystoseira sensu lato and Posidonia oceanica (L.) Delile, also highlighting their potential use as ecological biomarkers.

Gas-Lift Design: Importance of Well/Reservoir Full Life Cycle Consideration and Analysis

2021 ◽  
Author(s):  
Onyeka Onwuemene
Keyword(s):  
Life Cycle ◽  
Oil And Gas ◽  
Gas Injection ◽  
Important Variable ◽  
Design Technique ◽  
Well Performance ◽  
Full Life Cycle ◽  
Wide Range ◽  
Full Life ◽  
Gas Lift

Abstract This paper discusses how production rates can be sustained and further increased from an indepth gas-lift design that considers the holistic properties associated oil and gas Well production lifecycles. An example is shown of a Well 58 in a field onshore Nigeria which was shut-in for 2-days as part of scheduled Field shut-down. After several failed attempts to restart the Well post shut-down period, lessons learnt analysis indicated that while the affected Well had all the required gas-lift system installed, it's inability to flow may have been due to inadequate gas-lift design that did not account for the full life cycle of the reservoir, Well and surface facilities. A major re-analysis is carried out on the gas-lift design technique, this time capturing key requirements and the resultant proposal is discussed in detail. The proposed gaslift design optimizes the depth of gas injection with consideration given to the latter production phase of the the Well. Through the example of Well 58, this paper outlines and proposes a checklist of recommendations for gas lift design for new Wells and re-working or workover of existing gas-lift installations from which Well performance can be sustained and optimized. Even if quality gaslift-production results can be achieved through a wide range of other activities such as; special training for production operators, optimizing gas injection rates, modifying surface piping systems, identifying and replacing defective wireline-retrievable gas-lift valves, the most important variable that will ensure the full benefit of the above listed range of activities is the improved gas-lift design technique. Although Well 58 was revived via unconventional methods, the recorded 3-week downtime and the associated financial losses could have been avoided if an adequate gas lift design as proposed in this paper was explored during the Well planning and completion.

scholarly journals Full life-cycle monitoring and earlier warning for bolt joint loosening using modified vibro-acoustic modulation

2022 ◽  
Vol 162 ◽  
pp. 108054
Author(s):  
Xiaoshu Qin ◽  
Chang Peng ◽  
Gaozheng Zhao ◽  
Zengye Ju ◽  
Shanshan Lv ◽  
...  
Keyword(s):  
Life Cycle ◽  
Full Life Cycle ◽  
Full Life ◽  
Acoustic Modulation ◽  
Cycle Monitoring

The Effect of Temperature Fluctuation on the Formation of Billet Surface Defect in the Initial Solidification Area

2010 ◽  
Vol 148-149 ◽  
pp. 163-167
Author(s):  
Xiao Li Jin ◽  
Zuo Sheng Lei ◽  
Kang Deng ◽  
Zhong Ming Ren
Keyword(s):  
Continuous Casting ◽  
Temperature Fluctuation ◽  
Surface Defects ◽  
Casting Process ◽  
Effect Of Temperature ◽  
Billet Surface ◽  
Maximum Value ◽  
Key Factor ◽  
Oscillation Marks ◽  
Initial Solidification

The heat transfer in steel continuous casting process under mold oscillation was calculated, and temperature fluctuation phenomena was found in the initial solidification area, the maximum value was approximate 16 °C. The effect of different continuous casting parameters on temperature fluctuation were analyzed, and the temperature fluctuation was considered to be a key factor to the formation of oscillation marks. The Index of Temperature Fluctuation(ITF) was proposed to predict the effect of temperature fluctuation on the formation of billet surface defects.

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