scholarly journals Age, growth, and mortality of Loligo vulgaris wild paralarvae: implications for understanding of the life cycle and longevity

2010 ◽  
Vol 67 (6) ◽  
pp. 1119-1127 ◽  
Author(s):  
Ángel F. González ◽  
Jaime Otero ◽  
Graham J. Pierce ◽  
Ángel Guerra
Keyword(s):  
Life Cycle ◽  
Growth Rates ◽  
Total Mortality ◽  
Instantaneous Rate ◽  
Relative Growth Rates ◽  
Loligo Vulgaris ◽  
Growth Increments ◽  
Ría De Vigo ◽  
Size At Age ◽  
Almost All

Abstract González, Á. F., Otero, J., Pierce, G. J., and Guerra, Á. 2010. Age, growth, and mortality of Loligo vulgaris wild paralarvae: implications for understanding of the life cycle and longevity. – ICES Journal of Marine Science, 67: 1119–1127. Age, growth, and mortality were estimated for the first time in wild paralarvae of the common squid, Loligo vulgaris, by examining growth increments in the statoliths of 273 animals collected off the Ría de Vigo (NW Spain, NE Atlantic). Hatching was all year round for the period 2003–2005, with a peak during late spring and a secondary peak during early autumn. Paralarvae varied from 1260 to 7580 µm, and their abundance decreased abruptly as they grew. Statolith increments were clearly visible without grinding in almost all material, allowing reliable estimation of age. Paralarvae are planktonic for at least 3 months. Growth in dorsal mantle length (DML) during that period fitted an exponential equation. The instantaneous relative growth rates were 2.11, 2.15, and 1.82% DML d−1 for 2003, 2004, and 2005, respectively, and there were no significant differences in size-at-age between the 3 years. Taking into account the growth rates estimated for the whole cycle of L. vulgaris, we suggest that the lifespan may previously have been underestimated by 3 months, because the proximity of the rings deposited during paralarval and early juvenile stages would prevent accuracy in enumerating the number of growth increments in later stages. The estimated instantaneous rate of total mortality during the first 90 d of a paralarva life was 9.6, 5.3, and 4.8% d−1 for 2003, 2004, and 2005, respectively. Eye diameter was a reliable and rapid way of estimating DML and age.

Age, growth and maturation of the European squid Loligo vulgaris (Myopsida, Loliginidae) on the west Saharan shelf

1995 ◽  
Vol 75 (3) ◽  
pp. 593-604 ◽  
Author(s):  
Alexander Arkhipkin
Keyword(s):  
Life Cycle ◽  
Sexual Dimorphism ◽  
Power Function ◽  
Growth Rates ◽  
Gompertz Function ◽  
The West ◽  
Loligo Vulgaris ◽  
Growth Increments ◽  
Males And Females ◽  
June July

Age, growth and maturation of Loligo vulgaris were studied by examination of growth increments within statoliths of 294 specimens (mantle length, ML, ranging from 31 to 498 mm) caught on the west Saharan shelf between 1985 and 1988. Maximum age was 335 d (290 mm ML) for females, and 396 d (498 mm ML) for males. Growth rates varied considerably among individuals with a greater range in males. Sexual dimorphism in length was apparent after about 210 d. Males and females diverged considerably in weight, with males reaching a greater weight after about 180 d. Growth in length between 124 and 396 d was best described by a power function, while growth in weight was best described by the Gompertz function. Males started maturing at 180–210 d and mature males ranged in age between 250 and 396 d; while females started maturing at 240–270 d and mature females ranged between 285 and 335 d. Loligo vulgaris hatched throughout the year with two distinct peaks; in winter (December - early March) and summer (June-July). The life cycle of L. vulgaris populations on the west Saharan shelf lasts ~1 y, with large males (>450 mm ML) living slightly longer.

Life-history variation among populations of Canadian Toads in Alberta, Canada

2005 ◽  
Vol 83 (11) ◽  
pp. 1421-1430 ◽  
Author(s):  
Brian R Eaton ◽  
Cynthia A Paszkowski ◽  
Kent Kristensen ◽  
Michelle Hiltz
Keyword(s):  
Life History ◽  
Growth Rates ◽  
Life History Traits ◽  
Age At Maturity ◽  
Life History Variation ◽  
Size At Age ◽  
Almost All ◽  
Conservation Plans ◽  
Toad Bufo ◽  
Latitudinal Range

Development of appropriate conservation plans relies on life-history information and how life-history traits vary across populations of a species. Such data are lacking for many amphibians, including the Canadian Toad (Bufo hemiophrys Cope, 1886). Here we use skeletochronology to estimate size at age, growth rates, age at maturity, and longevity of toads from nine populations along a latitudinal gradient in Alberta, Canada. Size of individual toads within each year class was highly variable, but age and size (measured as snout-to-urostyle length) were significantly related for almost all populations. The largest individuals were found in the southern-most population, while the smallest toads were found in three populations from the middle of the latitudinal range studied. Growth rates were highest in the southern-most population and lowest at the three populations with relatively small individuals. Maximum age was from 7 to 12 years for the populations sampled. The oldest individuals were found in populations in the middle of the latitudinal range sampled; toads in these populations were smaller than those in all other populations. Age at maturity was 1 year old for males and 2 years old for females in most populations. This study shows that some life-history traits exhibit significant variation between Canadian Toad populations, suggesting that effective conservation of this species will need to include population or area-specific management.

scholarly journals CAD integrated automatic recognition of weld paths

2021 ◽  
Author(s):  
Tuan Anh Tran ◽  
Andrei Lobov ◽  
Tord Hansen Kaasa ◽  
Morten Bjelland ◽  
Ole Terje Midling
Keyword(s):  
Life Cycle ◽  
Spatial Analysis ◽  
Product Life Cycle ◽  
Real Life ◽  
Automatic Recognition ◽  
Integrated Method ◽  
Weld Joints ◽  
Related Information ◽  
Almost All ◽  
Sequential Assembly

AbstractIn this paper, a CAD integrated method is proposed for automatic recognition of potential weld locations in large assembly structures predominantly comprised of weld joints. The intention is to reduce the total man-hours spent on manually locating, assigning, and maintaining weld-related information throughout the product life cycle. The method utilizes spatial analysis of extracted stereolithographic data in combination with available CAD functions to determine whether the accessibility surrounding a given intersection edge is sufficient for welding. To demonstrate the method, a system is developed in Siemens NX using their NXOpen Python API. The paper presents the application of the method to real-life use cases in varying complexity in cooperation with industrial partners. The system is able to correctly recognize almost all weld lines for the parts considered within a few minutes. Some exceptions are known for particular intersection lines located deep within notched joints and geometries weldable through sequential assembly, which are left as a subject to further works.

P1818Descending aortic thoracic diameter: a risk marker for major adverse cardiovascular outcomes in women

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
O L Rueda Ochoa ◽  
L R Bons ◽  
S Rohde ◽  
K E L Ghoud ◽  
R Budde ◽  
...  
Keyword(s):  
Heart Failure ◽  
Cardiovascular Risk ◽  
Cardiovascular Mortality ◽  
Total Mortality ◽  
Population Based ◽  
Cardiovascular Outcomes ◽  
Increased Risk ◽  
Almost All

Abstract Background Thoracic aortic diameters have been associated with cardiovascular risk factors and atherosclerosis. However, limited evidence regarding the role of thoracic aortic diameters as risk markers for major cardiovascular outcomes among women and men exist. Purpose To evaluate the independent associations between crude and indexed ascending and descending aortic (AA and DA) diameters with major cardiovascular outcomes among women and men and to provide optimal cutoff values associated with increased cardiovascular risk. Methods and results 2178 women and men ≥55 years from the prospective population-based Rotterdam Study underwent multi-detector CT scan of thorax. Crude diameters of the AA and DA were measured and indexed by height, weight, body surface area (BSA) and body mass index (BMI). Incidence of stroke, coronary heart disease (CHD), heart failure (HF), cardiovascular and all-cause mortality were evaluated during 13 years of follow-up. Weight-, BSA-, or BMI-indexed AA diameters showed significant associations with total or cardiovascular mortality in both sexes and height-indexed values showed association with HF in women. Crude AA diameters were associated with stroke in men and HF in women. For DA, crude and almost all indexed diameters showed significant associations with either stroke, HF, cardiovascular or total mortality in women. Only weight-, BSA- and BMI-indexed values were associated with total mortality in men. For crude DA diameter, the risk for stroke increased significantly at the 75th percentile among men while the risks for HF and cardiovascular mortality increased at the 75th and 85th percentiles respectively in women. Conclusions Our study suggests a role for descending thoracic aortic diameter as a marker for increased cardiovascular risk, in particular for stroke, heart failure and cardiovascular mortality among women. The cut points for increased risk for several of cardiovascular outcomes were below the 95th percentile of the distribution of aortic diameters.

Selection for biomass production based on respiration parameters in eucalypts: effects of origin and growth climates on growth rates

1996 ◽  
Vol 26 (9) ◽  
pp. 1556-1568 ◽  
Author(s):  
Thimmappa S. Anekonda ◽  
Richard S. Criddle ◽  
Lee D. Hansen ◽  
Mike Bacca
Keyword(s):  
Temperature Dependence ◽  
Growth Rates ◽  
Heat Rate ◽  
Eucalyptus Species ◽  
Relative Growth ◽  
Relative Growth Rates ◽  
Metabolic Heat ◽  
Respiratory Parameters ◽  
Metabolic Heat Rate ◽  
Different Climates

Seventeen Eucalyptus species and 30 rapid-growing Eucalyptuscamaldulensis trees (referred to as plus trees), growing in a plantation were studied to examine relationships among measured plant growth and respiratory parameters, geographical origins, and growth climate. The respiratory parameters measured at two different temperatures by isothermal calorimetry were metabolic heat rate, rate of CO2 production, and the ratio of heat rate to CO2 rate. Metabolic heat rate was also measured as a continuous function of temperature by differential scanning calorimetry in the range of 10 to 40 °C. Tree growth was measured as rates of height and stem volume growth. The values of respiratory and growth variables of Eucalyptus species are significantly correlated with latitude and altitude of origin of their seed sources. The maximum metabolic heat rate, the temperature of the maximum heat rate, the temperature coefficients of metabolic rate, and the temperatures at which the slopes of Arrhenius plots change are all genetically determined parameters that vary both within and among species. Measurement of growth rate–respiration rate–temperature relationships guide understanding of why relative growth rates of Eucalyptus species and individual genotypes differ with climate, making it possible to identify genotypes best suited for rapid growth in different climates. The temperature dependence of respiration rates is an important factor determining relative growth rates of eucalypts in different climates. To achieve optimum biomass production the temperature dependence of individual plants must be matched to growth climate.

Studies on the sowing dates of cotton in the Sudan Gezira: I. The influence of date of sowing on plant growth and development

1967 ◽  
Vol 69 (3) ◽  
pp. 305-315 ◽  
Author(s):  
J. E. Jackson
Keyword(s):  
Growth Rates ◽  
Slow Growth ◽  
Seasonal Pattern ◽  
Relative Growth ◽  
Relative Growth Rates ◽  
Research Division ◽  
Sowing Dates ◽  
Net Assimilation ◽  
State Growth ◽  
Sudan Gezira

Growth analysis of cotton crops sown in the Sudan Gezira at monthly intervals between August and May revealed a marked seasonal pattern of growth. Irrespective of plant age and fruiting state growth of non-senescent plants was slowest during the cool winter months. Relative growth rates of young plants were highest in August, September and early October due to the high specific leaf areas and fairly high net assimilation rates found then. They were lowest when minimum temperatures were lowest. Net assimilation rates were also lowest in the coolest months, probably as a result of restricted growth. High temperatures in the spring reduced fruiting. It is concluded that low minimum temperatures and high evaporation rates are both associated with slow growth, and play a large part in determining the characteristic decline of growth rates of cotton sown at the usual date in August.I wish to thank the Chief of the Research Division, Ministry of Agriculture, Sudan, for permission to publish this paper and to record my gratitude to the team of field and laboratory assistants, especially Salih Saad and Hassan Osman, who helped in the work.

Age structure and life cycles of the Argentine shortfin squid Illex argentinus (Cephalopoda: Ommastrephidae) in southern Brazil

2012 ◽  
Vol 93 (2) ◽  
pp. 557-565 ◽  
Author(s):  
R. Schwarz ◽  
J.A.A. Perez
Keyword(s):  
Life Cycle ◽  
Age Structure ◽  
Life Cycles ◽  
Southern Brazil ◽  
Trawl Fishery ◽  
Growth Increments ◽  
Wide Range ◽  
Growth Zones ◽  
Illex Argentinus ◽  
Post Spawning

Age structure and hatchling dates of the squid Illex argentinus collected by bottom-trawl fishery in southern Brazilian waters were assessed by the analysis of statolith growth increments. Catches occurred between 2001 and 2002, from 23° to 32°S at depths of 100–700 m. Squid from juvenile to post-spawning stages were collected year round, with age estimated from 98 to 320 days and mantle lengths ranging from 112 to 376 mm. Duration of life cycle events based on statolith growth zones revealed that squids can spend about 14% of their lifespan as paralarva (~30 days), 70% as juvenile (~130 days), leaving maturity and spawning condition to the terminal 10–20% (~30–60 days). The results suggest that, unlike estimates available for Patagonian populations, a general 0.5 year lifespan is predicted for I. argentinus off Brazil. The wide range of size-at-ages implied that catches of shortfin squid off southern Brazil probably include squid hatched throughout the year. Mature and spawning squid caught in summer months hatched in winter and spring, while winter catches revealed mature-spawning individuals hatched both in summer/autumn (~6 months of age) and winter/spring periods (~10–11 months of age). It has been argued that such groups may combine both squid resident of Brazilian outer shelf and slope (22°–34°S) with a six months' lifespan and migrating squid originated from the northern Patagonian shelf (~42°S) with 10–11 months' lifespan.

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