Empirical analysis of the effect of temperature on marine harpacticoid copepod development time

Predictive equations to estimate development time from environmental temperature for marine harpacticoid copepods were developed from data extracted from the literature. Separate equations were constructed for egg, nauplius, copepodite, and total juvenile development, as well as for generation time. Power curves adequately described the data and each regression was significant (P < 0.001). Approximately 50% of the variance in each data set was explained by regression on temperature. Predictions of development time generally were precise, with the upper 95% confidence limit 39–65% greater than the prediction at low temperatures (4–5 °C), 7–13% greater at mean temperatures (17.6–19.3 °C), and 13–31% greater at high temperatures (28–40 °C). Application of these predictive equations will facilitate analysis of the population dynamics and production of marine harpacticoid copepods.

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Development time of harpacticoid copepods: some empirical models and implications

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315499001381 ◽

1999 ◽

Vol 79 (6) ◽

pp. 1123-1124 ◽

Cited By ~ 8

Author(s):

P.J.P. Santos ◽

J. Castel ◽

L.P. Souza-Santos

Keyword(s):

Body Length ◽

Development Time ◽

Environmental Temperature ◽

Harpacticoid Copepod ◽

Empirical Models ◽

Copepod Species ◽

Egg Development ◽

Rearing Temperature ◽

Development Times ◽

Harpacticoid Copepods

Some meiobenthic harpacticoid copepod species cannot be successfully cultured, therefore empirical models were developed to estimate their development times, using literature data, but taking into consideration several empirical rules previously formulated to model the development of planktonic copepods. The present models demonstrated the overwhelming influence of rearing temperature on egg development time, and of body length on total development time and indicate a capacity to adapt development rates to environmental temperature.

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Description of the life-history stages of Amphiascus undosus Lang (Copepoda, Harpacticoida)

Canadian Journal of Zoology ◽

10.1139/z91-078 ◽

1991 ◽

Vol 69 (2) ◽

pp. 512-527 ◽

Cited By ~ 1

Author(s):

Graham J. McMillan

Keyword(s):

Adult Development ◽

Development Time ◽

Harpacticoid Copepod ◽

Original Description ◽

Sexually Dimorphic ◽

Single Female ◽

Type Specimens ◽

Life History Stages ◽

Harpacticoid Copepods ◽

Similarities And Differences

The six naupliar and six copepodite stages of the harpacticoid copepod Amphiascus undosus Lang are described in detail. Thoracic leg segmentation and armature are presented in tabular form for the copepodite stages. The species becomes sexually dimorphic at the fourth copepodite stage. Average egg-to-adult development time is approximately 31.5 days at 22 ± 1 °C. Up to four successive pairs of egg sacs from a single female are produced in the laboratory, yielding a maximum of 76 progeny. Some discrepancies exist between the original description of the California type specimens and the present British Columbia material, particularly in the adult male maxillule, maxilliped, and first, fifth, and sixth legs, and the caudal setae of the adult female. A brief comparison is made with the developmental similarities and differences of six other diosaccid harpacticoid copepods.

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Dealing with hot rocky environments: Critical thermal maxima and locomotor performance in Leptodactylus lithonaetes (Anura: Leptodactylidae)

Herpetological Journal ◽

10.33256/hj29.3.155161 ◽

2019 ◽

pp. 155-161 ◽

Cited By ~ 1

Author(s):

Ivan Beltran

Keyword(s):

Environmental Temperature ◽

Extreme Temperature ◽

Effect Of Temperature ◽

Maximum Speed ◽

Locomotor Performance ◽

Extreme Temperatures ◽

Physiological Limits ◽

Fitness Consequences ◽

Thermal Maximum ◽

Environmental Temperatures

Environmental temperature has fitness consequences on ectotherm development, ecology and behaviour. Amphibians are especially vulnerable because thermoregulation often trades with appropriate water balance. Although substantial research has evaluated the effect of temperature in amphibian locomotion and physiological limits, there is little information about amphibians living under extreme temperature conditions. Leptodactylus lithonaetes is a frog allegedly specialised to forage and breed on dark granitic outcrops and associated puddles, which reach environmental temperatures well above 40 ˚C. Adults can select thermally favourable microhabitats during the day while tadpoles are constrained to rock puddles and associated temperature fluctuations; we thus established microhabitat temperatures and tested whether the critical thermal maximum (CTmax) of L. lithonaetes is higher in tadpoles compared to adults. In addition, we evaluated the effect of water temperature on locomotor performance of tadpoles. Contrary to our expectations, puddle temperatures were comparable and even lower than those temperatures measured in the microhabitats used by adults in the daytime. Nonetheless, the CTmax was 42.3 ˚C for tadpoles and 39.7 ˚C for adults. Regarding locomotor performance, maximum speed and maximum distance travelled by tadpoles peaked around 34 ˚C, approximately 1 ˚C below the maximum puddle temperatures registered in the puddles. In conclusion, L. lithonaetes tadpoles have a higher CTmax compared to adults, suggesting a longer exposure to extreme temperatures that lead to maintain their physiological performance at high temperatures. We suggest that these conditions are adaptations to face the strong selection forces driven by this granitic habitat.

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Characterizing population structure of coral-associated fauna from mesophotic and shallow habitats in the Caribbean

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315418000413 ◽

2018 ◽

Vol 99 (3) ◽

pp. 619-629 ◽

Cited By ~ 2

Author(s):

Alex J. Veglia ◽

Nicholas M. Hammerman ◽

Carlos R. Rivera Rosaly ◽

Matthew Q. Lucas ◽

Alexandra Galindo Estronza ◽

...

Keyword(s):

Population Structure ◽

Puerto Rico ◽

Marine Invertebrates ◽

Geographic Distance ◽

Harpacticoid Copepod ◽

Coi Gene ◽

Mitochondrial Coi ◽

Symbiotic Relationships ◽

Harpacticoid Copepods ◽

Obligate Symbiont

Symbiotic relationships are a common phenomenon among marine invertebrates, forming both obligatory and facultative dependencies with their host. Here, we investigate and compare the population structure of two crustacean species associated with both shallow and mesophotic ecosystems: an obligate symbiont barnacle (Ceratoconcha domingensis), of the coral Agaricia lamarcki and a meiobenthic, free-living harpacticoid copepod (Laophontella armata). Molecular analyses of the Cytochrome Oxidase Subunit I (COI) gene revealed no population structure between mesophotic and shallow barnacle populations within south-west Puerto Rico (ΦST = 0.0079, P = 0.33). The absence of population structure was expected due to the pelagic naupliar larvae of the barnacles and the connectivity patterns exhibited by the coral itself within the same region. Laophontella armata exhibited significant structure based on the mitochondrial COI gene between the mesophotic reef ecosystem of El Seco, Puerto Rico and mangrove sediments of Curaçao (ΦST = 0.2804, P = 0.0). The El Seco and Curaçao copepods shared three COI haplotypes despite the obligatory benthic development of harpacticoid copepods and the geographic distance between the two locations. Three other COI haplotypes from El Seco exhibited higher than expected (up to 7%) intra-species variability, potentially representing three new cryptic species of harpacticoid copepods or rare, deeply divergent lineages of L. armata. This result is evidence for the urgent need of a deeper investigation into the meiofauna diversity associated with mesophotic coral ecosystems (MCEs), arguably the most diverse metazoan component of MCEs.

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Influence of the Insecticide Diflubenzuron (Dimilin) on the Growth of Marine Diatoms and a Harpacticoid Copepod in Culture

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f85-158 ◽

1985 ◽

Vol 42 (7) ◽

pp. 1272-1277 ◽

Cited By ~ 6

Author(s):

N. J. Antia ◽

P. J. Harrison ◽

D. S. Sullivan ◽

T. Bisalputra

Keyword(s):

Skeletonema Costatum ◽

Harpacticoid Copepod ◽

Adult Survival ◽

Thalassiosira Weissflogii ◽

Marine Diatoms ◽

Tigriopus Californicus ◽

Per Se ◽

Juvenile Development ◽

Cyclotella Cryptica ◽

Injurious Effects

Diflubenzuron (Dimilin) was tested, in the concentration range 0.1–5000 μg∙L−1, for possible injurious effects on the growth and photosynthesis of three chitin-producing (Thalassiosira weissflogii, T. norden-skioldii, Cyclotella cryptica) and one nonchitinaceous (Skeletonema costatum) diatoms. For comparison, the effects of the pesticide were also examined on adult survival and juvenile development of the harpacticoid copepod Tigriopus californicus. While the development of the copepod was hindered at concentrations of the order of 1–10 μg∙L−1, the diatoms were barely affected by Dimilin even at the highest concentration tested (5 mg∙L−1). We conclude that Dimilin acts specifically on insects and crustaceans as a larvicide by interfering with chitin deposition into cuticles during juvenile development through ecdysis. The lack of effect from Dimilin on the chitin-producing diatoms has suggested that the insecticide may not inhibit chitin biosynthesis per se as was previously believed, but that it presumably deregulates one or more of the larval postsynthetic processes responsible for chitin integration into cuticles.

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Evolving while invading: rapid adaptive evolution in juvenile development time for a biological control organism colonizing a high-elevation environment

Evolutionary Applications ◽

10.1111/j.1752-4571.2012.00278.x ◽

2012 ◽

Vol 5 (5) ◽

pp. 524-536 ◽

Cited By ~ 31

Author(s):

Peter B. McEvoy ◽

Kimberley M. Higgs ◽

Eric M. Coombs ◽

Evrim Karaçetin ◽

Leigh Ann Starcevich

Keyword(s):

Biological Control ◽

Adaptive Evolution ◽

Development Time ◽

High Elevation ◽

Juvenile Development

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Influence of the environmental temperature on the post-partum testosterone surge in the rat

Acta Endocrinologica ◽

10.1530/acta.0.1150478 ◽

1987 ◽

Vol 115 (4) ◽

pp. 478-482 ◽

Cited By ~ 4

Author(s):

J. Roffi ◽

F. Chami ◽

P. Corbier ◽

D. A. Edwards

Keyword(s):

Ambient Temperature ◽

Environmental Temperature ◽

Post Partum ◽

Serum Testosterone ◽

The Body ◽

Male Rats ◽

Effect Of Temperature ◽

Male Rat ◽

Foster Mother ◽

The Central Nervous System

Abstract. In the neonatal male rat, a rapid and transient increase in serum testosterone occurs about 2 h after birth. This post-partum testosterone surge (PPTS) has been implicated in the masculinization and defeminization of the central nervous system. The present study shows that environmental temperature can have a profound influence on the PPTS. Male rats were delivered from their mothers by caesarean section on day 22 of gestation. Immediately thereafter, neonatal males were placed at an ambient temperature of either 18, 21, 24 or 30°C. With 2 h of exposure, the body temperature was in close correspondence with the ambient temperature. The PPTS was clearly abolished in the pups exposed for 2 h at either 18 or 21°C. The effect of temperature was reversible: by placing pups at either 18 or 21°C for 2 h after delivery, and then rewarming by placing them with a foster mother, the PPTS was delayed until 4 h after birth, i.e. 2 h after the beginning of rewarming. Thus, environmental cooling appears to retard the development of neural and/or endocrine systems mediating the PPTS. Aberrant maternal care which would produce substantial cooling of the male pups would be expected to affect the PPTS, which in turn might affect the sexuality of male progeny.

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Data Augmentation for Electricity Theft Detection Using Conditional Variational Auto-Encoder

Energies ◽

10.3390/en13174291 ◽

2020 ◽

Vol 13 (17) ◽

pp. 4291

Author(s):

Xuejiao Gong ◽

Bo Tang ◽

Ruijin Zhu ◽

Wenlong Liao ◽

Like Song

Keyword(s):

Latent Variables ◽

Data Augmentation ◽

Sampling Technique ◽

Smart Meters ◽

Generative Adversarial Network ◽

Data Set ◽

Electricity Theft ◽

Adversarial Network ◽

Low Dimensional ◽

Power Curves

Due to the strong concealment of electricity theft and the limitation of inspection resources, the number of power theft samples mastered by the power department is insufficient, which limits the accuracy of power theft detection. Therefore, a data augmentation method for electricity theft detection based on the conditional variational auto-encoder (CVAE) is proposed. Firstly, the stealing power curves are mapped into low dimensional latent variables by using the encoder composed of convolutional layers, and the new stealing power curves are reconstructed by the decoder composed of deconvolutional layers. Then, five typical attack models are proposed, and the convolutional neural network is constructed as a classifier according to the data characteristics of stealing power curves. Finally, the effectiveness and adaptability of the proposed method is verified by a smart meters’ data set from London. The simulation results show that the CVAE can take into account the shapes and distribution characteristics of samples at the same time, and the generated stealing power curves have the best effect on the performance improvement of the classifier than the traditional augmentation methods such as the random oversampling method, synthetic minority over-sampling technique, and conditional generative adversarial network. Moreover, it is suitable for different classifiers.

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Full-Scale Wind Turbine Vibration Signature Analysis

Machines ◽

10.3390/machines6040063 ◽

2018 ◽

Vol 6 (4) ◽

pp. 63 ◽

Cited By ~ 6

Author(s):

Xavier Escaler ◽

Toufik Mebarki

Keyword(s):

Wind Farm ◽

Power Spectra ◽

Operating Conditions ◽

Drive Train ◽

Normal Operation ◽

Common Source ◽

Variable Speed ◽

Data Set ◽

Vibration Signature ◽

Power Curves

A sample of healthy wind turbines from the same wind farm with identical sizes and designs was investigated to determine the average vibrational signatures of the drive train components during normal operation. The units were variable-speed machines with three blades. The rotor was supported by two bearings, and the drive train connected to an intermediate three-stage planetary/helical gearbox. The nominal 2 MW output power was regulated using blade pitch adjustment. Vibrations were measured in exactly the same positions using the same type of sensors over a six-month period covering the entire range of operating conditions. The data set was preliminary validated to remove outliers based on the theoretical power curves. The most relevant frequency peaks in the rotor, gearbox, and generator vibrations were detected and identified based on averaged power spectra. The amplitudes of the peaks induced by a common source of excitation were compared in different measurement positions. A wind speed dependency of broadband vibration amplitudes was also observed. Finally, a fault detection case is presented showing the change of vibration signature induced by a damage in the gearbox.

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