Phocanema decipiens (Nematoda: Anisakinae): experimental infections in marine copepods

1982 ◽  
Vol 60 (4) ◽  
pp. 502-509 ◽  
Author(s):  
Gary McClelland
Keyword(s):  
Gravid Female ◽  
Mature Female ◽  
Cyclopoid Copepod ◽  
Calanoid Copepods ◽  
North West ◽  
The North ◽  
The Family ◽  
The Mean ◽  
Mean Time ◽  
Marine Copepods

Gravid female Phocanema decipiens were recovered from the stomachs of freshly killed harbour (Phoca vitulina) and grey seals (Halichoerus grypus). Ova dissected from the nematodes were incubated in seawater and the mean time to hatch varied from 8 days at 20 °C to 52 days at 5 °C. Posthatch survival of ensheathed larvae in seawater varied from 48 h at 20 °C to 140 days at 5 °C. Fifteen species of copepods collected from the North West Arm, Halifax, N.S., were exposed to freshly hatched larvae of P. decipiens. Exsheathed larvae of the parasite were subsequently detected in the haemocoel of 12 harpacticoid species including Danielsennia typica, Tisbe furcata, Ameira longipes, Enhydrosoma curticauda, and various undescribed species of the genera Halectinosoma, Tisbe, Alteutha, and Phyllothallestris and the family Diosaccidae. Phocanema decipiens also occurred in a cyclopoid copepod (Paracyclopina sp.) but calanoid copepods (Eurytemora sp. and Pseudocalanus sp.) did not become infected. The heaviest infections occurred in mature female copepods and prevalence and intensity of infection varied with host species. Adult male copepods and fifth copepodite females were lightly infected. Infected copepods survived for 3–7 days at 15 °C, 10–15 days at 10 °C, and 20–35 days at 5 °C. During the course of infection, larval P. decipiens grew an average of 60% and maximum of 130% in length but underwent little or no morphological change.

scholarly journals On tho proportions of the prevailing winds, the mean temperature, and depth of rain in the climate of London, computed through a cycle of Eighteen Years, or periods of the Moon’s declination

1843 ◽  
Vol 4 ◽  
pp. 300-300
Keyword(s):  
The Moon ◽  
Fair Weather ◽  
North West ◽  
West Wind ◽  
North East ◽  
East Wind ◽  
The North ◽  
The Common ◽  
The Mean ◽  
Solar Influence

In this paper the author investigates the periodical variations of the winds, rain and temperature, corresponding to the conditions of the moon’s declination, in a manner similar to that he has already followed in the case of the barometrical variations, on a period of years extending from 1815 to 1832 inclusive. In each case he gives tables of the average quantities for each week, at the middle of which the moon is in the equator, or else has either attained its maximum north or south declination. He thus finds that a north-east wind is most promoted by the constant solar influence which causes it, when the moon is about the equator, going from north to south; that a south-east wind, in like manner, prevails most when the moon is proceeding to acquire a southern declination ; that winds from the south and west blow more when the moon is in her mean degrees of declination, going either way, than with a full north or south declination ; and that a north-west wind, the common summer and fair weather wind of the climate, affects, in like manner, the mean declination, in either direction, in preference to the north or south, and most when the moon is coming north. He finds the average annual depth of rain, falling in the neighbourhood of London, is 25’17 inches.

scholarly journals Biochemical parameters variations with season, age, sex, parity and pregnancy in crossbred goats raised in Tiaret, Algeria

2021 ◽  
Vol 8 (1) ◽  
pp. 69-79
Author(s):  
Berrani Abdelkader ◽  
Meliani Samia ◽  
Bourabah Akila
Keyword(s):  
Significant Influence ◽  
Biochemical Parameters ◽  
Physiological State ◽  
Mean Values ◽  
North West ◽  
The North ◽  
Nutritional Conditions ◽  
Physiological Stage ◽  
The Mean ◽  
Calcium And Phosphorus

Abstract The aim of this study was to determine the influence of season, age, sex, parity and gestation status on some biochemical parameters in local cross-bred goats raised in Tiaret, Algeria. Ninety cross bred local goats, from 2019 to 2020, aged between nine and seventy-two months at different physiological stage were used. Animals belong to different farms in Tiaret located at the north-west Algeria (35°22’ N, 1°19’ E). The mean values of triglycerides, creatinine and calcium were significantly (p<0,05) higher in winter than in spring. The physiological state of the goat had a significant influence (p<0,05) on cholesterol, urea, total proteins, calcium and phosphorus, with a high average values in non-pregnant goats, while triglycerides and globulin had significant higher values in postpartum and pregnant femals, respectively. In our work, parity had a significant influence (p<0,05) on cholesterol, calcium and phosphorus, with high average values in young goats and a significant influence (p<0,05) on triglycerides and creatinine with high average values in primiparous ones. Age significantly influenced (p<0,05) cholesterol, triglycerides, total protein, calcium and globulin. The results obtained from this study could serve as reference values for the local goats and other regions or countries with similar climatic and nutritional conditions.

scholarly journals Familial Thrombosis Due to Antithrombin III Deficiency: An Extensive Family Study

1977 ◽  
Author(s):  
Bruce Bennett ◽  
Michael Mackie ◽  
Alexander S. Douglas
Keyword(s):  
Small Bowel ◽  
Antithrombin Iii ◽  
Massive Pulmonary Embolism ◽  
Autosomal Dominant Disorder ◽  
Bowel Infarction ◽  
North West ◽  
Mesenteric Vein ◽  
The North ◽  
The Family ◽  
Antithrombin Iii Deficiency

A family living in Lewis (a Hebridean Island off the north west coast of Scotland) affected by antithrombin III deficiency has been studied. Two members have died, one of massive pulmonary embolism and one of major mesenteric infarction secondary to mesenteric vein occlusion. A further individual has sustained major small bowel infarction secondary to mesenteric vein thrombosis but survived after two small bowel resections followed by anticoagulant therapy. Other members of the family have suffered from nonfatal thrombotic events particularly during pregnancy. 57 individuals representing several generations have been studied and will be presented. Levels of antithrombin III measured by functional assays correlated well with those of antithrombin III measured immunologically. 12 members of the family showed moderate to severe deficiency of antithrombin III, the occurrence of thrombotic symptoms correlating well with deficiency of this protein. Transmission of the disorder as an autosomal dominant disorder is confirmed in the patients studied and by historical evidence over many generations.

On the current enhancement at the edge of a crack in a lattice of resistors

1998 ◽  
Vol 30 (2) ◽  
pp. 342-364 ◽  
Author(s):  
Howard M. Taylor ◽  
Dennis E. Sweitzer
Keyword(s):  
Random Walk ◽  
Vertical Direction ◽  
Potential Gradient ◽  
Domain Of Attraction ◽  
Lattice Points ◽  
Fourier Methods ◽  
The North ◽  
The Mean ◽  
Mean Time ◽  
Cauchy Process

Consider a network whose nodes are the integer lattice points and whose arcs are fuses of 1Ω resistance. Remove a horizontal segment ofNadjacent vertical arcs, forming a ‘crack’ of lengthN. Subject the network to a uniform potential gradient ofvvolts per arc in the north-south (or vertical) direction and measure the current in one of the two vertical arcs at the ends of the crack. We write this current in the forme(N)v, and calle(N) thecurrent enhancement.We show that the enhancement grows at a rate that is the order of the square root of the crack length. Our method is to identify the enhancement with the mean time to exit an interval for a certain integer valued random walk, and then to use some of the well-known Fourier methods for studying random walk. Our random walk has no mean or higher moments and is in the domain of attraction of the Cauchy law. We provide a good approximation to the enhancement using the explicitly known mean time to exit an interval for a Cauchy process. Weak convergence arguments together with an estimate of a recurrence probability enable us to show that the current in an intact fuse, that is in the interior of a crack of lengthN, grows p roportionally withN/logN.

scholarly journals Patterns and traits associated with invasions by predatory marine crabs

NeoBiota ◽  
2018 ◽  
Vol 39 ◽  
pp. 79-102 ◽  
Author(s):  
Cheruscha Swart ◽  
Vernon Visser ◽  
Tamara B. Robinson
Keyword(s):  
Alien Species ◽  
Invasion Success ◽  
Biological Knowledge ◽  
North West ◽  
Trait Analysis ◽  
The North ◽  
Biological Trait ◽  
The Family ◽  
Successful Establishment ◽  
Specific Species

Predatory crabs are considered amongst the most successful marine invasive groups. Nonetheless, most studies of these taxa have been descriptive in nature, biased towards specific species or regions and have seldom considered traits associated with invasiveness. To address this gap in knowledge, this study presents a global review of invasions by this group and applies biological trait analysis to investigate traits associated with invasion success. A total of 56 species belonging to 15 families were identified as having spread outside their native ranges. The family Portunidae supported the highest number of alien species (22). Most crabs had their origin in the North West Pacific IUCN bioregion while the Mediterranean Sea received the most species. No traits associated with successful establishment were identified, but this finding may reflect the paucity of basic biological knowledge held for many species. This lack of foundational knowledge was unexpected as crabs are large and conspicuous and likely to be well studied when compared to many other groups. Addressing this knowledge gap will be the first step towards enabling approaches like biological trait analysis that offer a means to investigate generalities in invasions.

scholarly journals The Mass Balance of the Devon Island Ice Cap, Northwest Territories, Canada, 1961-66

1970 ◽  
Vol 9 (57) ◽  
pp. 325-336 ◽  
Author(s):  
R.M. Koerner
Keyword(s):  
Mass Balance ◽  
Equilibrium Line ◽  
Accumulation Pattern ◽  
North West ◽  
Average Value ◽  
Devon Island ◽  
Ice Cap ◽  
The North ◽  
West Part ◽  
The Mean

Methods used in measuring the mass balance of the Devon Island ice cap are described. The use of dyes and melt trays is recommended in the superimposed-ice and firn zones of sub-polar glaciers. The north-west part of the ice cap was studied in most detail and has had a slightly negative net balance for the period 1961-66. An inverse relationship between mean net balance(bn)and elevation of the equilibrium line in the north-west part of the ice cap indicates that the mean net balance there would be zero with an equilibrium line at 920 m (±80 m) elevation. Accumulation on the ice cap is greatest in the south-east but the measurements suggest that the mean net balance there is similar to the mean net balance on the rest of the ice cap. It is concluded that the present accumulation pattern must have existed for several hundreds, and possibly thousands of years. A study of firn stratigraphy and of variations in the elevation of the firn and equilibrium lines indicates that between 1961 and 1966 only 1962 had a more negative mean net balance than the average value for the period 1934-60. During the same 26 year period the net balance at 1 787 m elevation has varied, but summer conditions do not appear to have changed significantly.

The Tasmanian Trout Fishery. II. The Fishery of the North-West Region

1958 ◽  
Vol 9 (1) ◽  
pp. 19 ◽  
Author(s):  
AG Nicholls
Keyword(s):  
Mortality Rate ◽  
Detailed Consideration ◽  
North West ◽  
Hatchery Fish ◽  
The North ◽  
West Region ◽  
Change In The Mean ◽  
The Mean ◽  
Trout Fishery ◽  
Annual Mortality

A brief account is given of the several rivers, and of the results derived from the study of the fishery in each. Anglers' returns of catches have been analysed with respect to the daily catch per angler for nine seasons, and the lengths of fish for five seasons, and the results are similar for each river. Detailed consideration of a summary of the data received from all sources in this region shows a definite downward trend in the daily catch which is statistically significant and more pronounced in the estuarine than in the inland fishery. There has been no change in the mean lengths of fish taken, and the size distribution of the catch has remained constant over five seasons. An 80 per cent. annual mortality rate has been found for fish from 1 to 6 years of age, after which it falls slightly. The total annual catch has risen with the increase in licensed anglers. Analysis of the diary of one angler over 27 years shows a decline in the catching rate, but the mean weight of fish has remained fairly constant. No direct consistent correlation was found between the estuarine trout fishery and the commercial whitebait fishery. It is concluded that the decline in catching rate is probably related to a change in the representation of anglers making returns during the nine seasons. A study of the contribution made by the release of hatchery fish shows a maximum possible return to anglers of 2 per cent., subject to a correction for the proportion of takable fish caught by anglers for which no data are available. Evidence is produced to show that the release of hatchery fish is unproductive and wasteful in a stream already stocked to capacity.

Recent Cyprididae and Ilyocyprididae (Crustacea: Ostracoda) from Lake Biwa, Japan, including a summary of the lake’s ostracod fauna

Zootaxa ◽  
2011 ◽  
Vol 2874 (1) ◽  
pp. 1 ◽  
Author(s):  
ROBIN J. SMITH ◽  
HORST JANZ ◽  
ICHIRO OKUBO
Keyword(s):  
New Record ◽  
Lake Biwa ◽  
New Records ◽  
First Record ◽  
Ancient Lake ◽  
The North ◽  
The Family ◽  
The Mean ◽  
Ostracod Species

Sampling between 1999 and 2007 of the recent ostracod fauna of Lake Biwa, an ancient lake located in Japan, produced ten Cyprididae and one Ilyocyprididae species. One Cyprididae species, belonging to the genus Ilyodromus is described herein, Ilyodromus intermedius Okubo n. sp., and Bradleytriebella lineata (Victor & Fernando, 1981c) is redescribed. One Cyprididae species is a new record for Japan, namely Stenocypris malayica Victor & Fernando, 1981a, while seven others are new records for Lake Biwa. The family Ilyocyprididae is represented by only one species in Lake Biwa, Ilyocypris salebrosa Stepanaitys, 1960. The Lake Biwa population of this species is the first record of males and they are described in this paper. Including this study, forty ostracod species have now been reported from Lake Biwa. Most species (70%) were found at depths of less than 1 meter. Only four species were found below 44 m, the mean depth of the north basin.

scholarly journals AMM15: a new high-resolution NEMO configuration for operational simulation of the European north-west shelf

2018 ◽  
Vol 11 (2) ◽  
pp. 681-696 ◽  
Author(s):  
Jennifer A. Graham ◽  
Enda O'Dea ◽  
Jason Holt ◽  
Jeff Polton ◽  
Helene T. Hewitt ◽  
...  
Keyword(s):  
High Resolution ◽  
Horizontal Resolution ◽  
Bias Reduction ◽  
Small Scale ◽  
Operational System ◽  
North West ◽  
The North ◽  
European North ◽  
The Mean ◽  
Mean State

Abstract. This paper describes the next-generation ocean forecast model for the European north-west shelf, which will become the basis of operational forecasts in 2018. This new system will provide a step change in resolution and therefore our ability to represent small-scale processes. The new model has a resolution of 1.5 km compared with a grid spacing of 7 km in the current operational system. AMM15 (Atlantic Margin Model, 1.5 km) is introduced as a new regional configuration of NEMO v3.6. Here we describe the technical details behind this configuration, with modifications appropriate for the new high-resolution domain. Results from a 30-year non-assimilative run using the AMM15 domain demonstrate the ability of this model to represent the mean state and variability of the region.Overall, there is an improvement in the representation of the mean state across the region, suggesting similar improvements may be seen in the future operational system. However, the reduction in seasonal bias is greater off-shelf than on-shelf. In the North Sea, biases are largely unchanged. Since there has been no change to the vertical resolution or parameterization schemes, performance improvements are not expected in regions where stratification is dominated by vertical processes rather than advection. This highlights the fact that increased horizontal resolution will not lead to domain-wide improvements. Further work is needed to target bias reduction across the north-west shelf region.

scholarly journals AMM15: A new high resolution NEMO configuration for operational simulation of the European North West Shelf

2017 ◽  
Author(s):  
Jennifer A. Graham ◽  
Enda O’Dea ◽  
Jason Holt ◽  
Jeff Polton ◽  
Helene T. Hewitt ◽  
...  
Keyword(s):  
High Resolution ◽  
Horizontal Resolution ◽  
Bias Reduction ◽  
Small Scale ◽  
Operational System ◽  
North West ◽  
The North ◽  
European North ◽  
The Mean ◽  
Mean State

Abstract. This paper describes the next generation ocean forecast model for the European North West Shelf, which will become the basis of operational forecasts in 2018. This new system will provide a step change in resolution, and therefore our ability to represent small scale processes. The new model has a resolution of 1.5 km, compared with a grid spacing of 7 km in the current operational system. AMM15 (Atlantic Margin Model, 1.5 km) is introduced as a new regional configuration of NEMO v3.6. Here we describe the technical details behind this configuration, with modifications appropriate for the new high resolution domain. Results from a 30 year non-assimilative run, using the AMM15 domain, demonstrate the ability of this model to represent the mean state and variability of the region. Overall, there is an improvement in the representation of the mean state across the region, suggesting similar improvements may be seen in the future operational system. However, the reduction in seasonal bias is greater off-shelf than on-shelf. In the North Sea, biases are largely unchanged. Since there has been no change to the vertical resolution or parameterisation schemes, performance improvements are not expected in regions where stratification is dominated by vertical processes, rather than advection. This highlights the fact that increased horizontal resolution will not lead to domain-wide improvements. Further work is needed to target bias reduction across the North West Shelf region.

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