Carapace width-weight relationships of blue swimmer crab Portunus armatus (A. Milne-Edwards, 1861) (Crustacea: Brachyura: Portunidae) in southwestern Australia: influences of sex, decadal change, environment, and season

2020 ◽  
Vol 40 (5) ◽  
pp. 526-533
Author(s):  
Danielle J Johnston ◽  
Daniel E Yeoh

Abstract The relationship between carapace width (CW) and weight (W) of the blue swimmer crab Portunus armatus (A. Milne-Edwards, 1861) was determined for southwestern Australian populations using measurements collected over two decades from a range of nearshore marine and estuarine environments. A strong and significant positive linear relationship occurred between the natural logarithm (ln) of CW and ln(W) for both sexes overall and individually for males and females (R2 = 0.985–0.987; P < 0.001). The relationships were: overall ln(W) = −10.2262 + 3.1708 ln(CW); males ln(W) = −10.4641 + 3.234 ln(CW), and females ln(W) = −10.0595 + 3.1246 ln(CW). Significant differences in the relationship were detected between sexes, decadal sampling periods, environments, and seasons (P < 0.001), with sex and decadal period being most influential. Males were heavier than females at any given CW, which was most apparent at larger (>100 mm CW) sizes. Crabs were also generally heavier at CW in a recent sampling period (2014–2019) than historically (1995–2000), with the greatest decadal differences occurring in the estuarine environment. These relationships have direct applicability for use in stock assessments of this valuable fishery species. Moreover, observed changes in the CW-W relationships over time highlight the importance of regularly reviewing biological parameters used in fisheries assessments, particularly in response to climate change as in the case of southwestern Australia.

2017 ◽  
Vol 64 (3) ◽  
Author(s):  
Durga Prasad Behera ◽  
S. Y. Tenjing ◽  
Rocktim Ramen Das ◽  
Laxman Nayak ◽  
D. Mohapatra

The relationship between carapace length (CL), carapace width (CW) and total weight (TW) in the flower moon crab Matuta planipes Fabricius, 1798 was studied and found to be CL = 0.144+1.319 CW and CL = 0.356+1.273 CL for males and females respectively. In case of the carapace width and total weight, the relationships were: TW = 0.272 CW3.011 and TW = 0.474 CW2.555 for males and females respectively. The relationships of carapace length and total weight were: TW = 0.128 CL2.917 for males and TW = 0.184 CL2.650 for females. A linear pattern was found between the relationship of CL and CW for M. planipes, whereas a curvilinear pattern was found between the relationship of CL/CW and TW in the present study. It was also observed that M. planipes is an opportunistic omnivore, seaweed being the most dominant food item followed by crustaceans, seagrass, amphipods and miscellaneous matter.


2004 ◽  
Vol 9 (1) ◽  
pp. 43-55 ◽  
Author(s):  
Patrizia Vermigli ◽  
Alessandro Toni

The present research analyzes the relationship between attachment styles at an adult age and field dependence in order to identify possible individual differences in information processing. The “Experience in Close Relationships” test of Brennan et al. was administered to a sample of 380 individuals (160 males, 220 females), while a subsample of 122 subjects was given the Embedded Figure Test to measure field dependence. Confirming the starting hypothesis, the results have shown that individuals with different attachment styles have a different way of perceiving the figure against the background. Ambivalent and avoidant individuals lie at the two extremes of the same dimension while secure individuals occupy the central part. Significant differences also emerged between males and females.


2020 ◽  
pp. 003329412097175
Author(s):  
Johanna Levallius ◽  
Elin Monell ◽  
Andreas Birgegård ◽  
David Clinton ◽  
Emma Forsén Mantilla

Introduction Binge eating is a common behaviour that is strongly linked to both obesity and eating disorder. There is evidence that binge eating commonly co-occurs with other problematic and addictive-like behaviours; however, this has not been explored systematically. The present study aimed to examine the relationship between binge eating, body weight, disordered eating behaviours and associated addictive-like behaviours, with particular attention paid to gender differences. Method A community sample ( N = 500; 75% female, Mage = 32.5 years) reported disordered eating behaviours (i.e. binge eating, purging, restriction of eating, compulsive exercise), body mass index (BMI), food addiction, starvation addiction, exercise dependence, tobacco use and alcohol consumption. Results 42% of females and 21% of males reported binge eating during the past four weeks. Binge eating was significantly associated with all investigated behaviours in females, and with purging, compulsive exercise and overweight/obesity in males. Controlling for BMI, self-starvation predicted binge eating in males (OR = 1.07), while food addiction (OR = 1.73) and alcohol dependence (OR = 1.11) predicted binge eating in females. Conclusions The multiple associations between binge eating and addictive-like behaviors supports broad screening and generalized prevention efforts. Prevention efforts should reflect gender differences.


Author(s):  
D. Sahoo ◽  
S. Panda ◽  
B.C. Guru

Portunus pelagicus a commercially important crab species found in Chilika lagoon constitutes about 20% of the total crab production. The carapace width (CW) ranges from 4.5–10.5 cm in both the sexes during the study period. The maximum abundance of male was at 6.6 to 7.5 cm CW whereas the females predominate from 6.6 to 9.5 cm CW. The relationship between carapace length (CL) and CW is linear in both sexes which indicates isometric growth. However, the relationship between CL, CW with total body weight (TW) is exponential. The food habit from gut content analysis shows that the species is highly carnivorous and the main food items include prawn carapace and appendages (27.58%), molluscan remaining (21.55%), fish bone (7.75%), seagrass (1.72%), unidentified materials (4.31%) and the mixed food (37.06%). The feeding index was found highest (80.95%) in February whereas it is lowest (60.9%) in June. The mature females are observed from May to July with a peak in July in the lagoon. The highest gonadosomatic index is found in July with an average CW of 10.5 cm. No berried females are found in the study period, which indicates that it did not spawn inside the lagoon and migrates to the sea during the rainy season.


2021 ◽  
pp. 25-29
Author(s):  
A. E. Barulin ◽  
S. V. Klauchek ◽  
A. E. Klauchek

Purpose of the study. To establish the relationship between neurophysiological status and the level of efficiency in young people with bruxism.Materials and methods. Two groups of 64 and 53 subjects (males and females) aged 20–35 years old with bruxism and non-bruxers were formed according to questionnaire results and physical examination. The level of efficiency was assessed by the results of sensorimotor tracking of a moving object (the ‘Smile’ model). Spectral analysis was performed for evaluation of the baseline electroencephalograms. Microsoft Excel and Statistica 10.0 programs were used for statistical data processing.Results. The level of efficiency was statistically significantly lower in the hardest test of Smile model among the individuals with bruxism (p < 0.05). The bruxers also demonstrated a significantly lower dominant frequency and maximum amplitude of alpha-rhythm (p < 0.05), and significantly higher dominant frequency of beta2 rhythm (p < 0.05). The dominant frequency and the maximum amplitude of the alpha-rhythm are parameters corresponding to significant coefficients of the regression analysis. A negative relationship was found between the degree of error during sensorimotor tracking and the frequency and amplitude of alpha-rhythm.Conclusion. Regression models present the relationship between the level of efficiency and the alpha-rhythm severity. The regression equations make it possible to determine the functional state of the subject using an electroencephalogram.


1974 ◽  
Vol 22 (3) ◽  
pp. 417 ◽  
Author(s):  
NA Campbell ◽  
RJ Mahon

A multivariate approach has been used to study morphological variation in the blue and orange-form species of rock crab of the genus Leptograpsus. Objective criteria for the identification of the two species are established, based on the following characters: width of the frontal region of the carapace; width of the posterior region of the carapace (rear width); length of the carapace along the midline; maximum width of the carapace; and the depth of the body. The first canonical variate, which differentiates between the two species, represents a contrast between the carapace width relative to the width of the front lip and the depth of the body; the blue-form species has a greater relative carapace width than has the orange form. The second canonical variate, which presents a contrast between the rear width and the carapace length, identifies males and females within each species; males have a greater relative carapace length than have females. All individuals, including 20 not used in the study, were correctly identified for colour form. The clear separation of the blue and orange forms achieved by canonical analysis supports the previously determined specific status of the two forms.


1993 ◽  
Vol 24 (1) ◽  
pp. 49-72 ◽  
Author(s):  
Horst Bohn

AbstractBohn, H.: Revision of the panteli-group of Phyllodromica in Spain and Morocco (Blattaria: Blattellidae: Ectobiinae). Ent. scand. 24: 49-72. Copenhagen, Denmark. April 1993. ISSN 0013-8711. The species of the panteli-group are characterized by lobiform wings in both sexes and very specialized glands on tergite 7 in the males consisting of two pairs of long tubular pouches. The five or six species are distributed in southern Spain (P. panteli (Bolívar), P. coniformis sp. n., P. ignabolivari sp. n.) and northern Morocco (P. Janeri (Bolívar), P. vignai (Failla & Messina), P. sp. B). The distribution pattern suggests a colonization of Morocco from Spain across the Strait of Gibraltar. The characteristics of the panteli-group are reported, the relationship with other groups is discussed, all species are described and depicted, and keys for the identification of males and females are presented.


2014 ◽  
Vol 9 (2) ◽  
pp. 97 ◽  
Author(s):  
Isaac Estevan ◽  
Octavio Álvarez ◽  
Coral Falcó ◽  
Isabel Castillo

Development of self-efficacy scales allows the analysis of athletes’ perceptions and examination of the relationship between perception and performance. The aim of this paper was to: (1) develop a specific self-efficacy scale in a taekwondo task, the roundhouse kick, and (2) analyse the sport performance and its relationship with two self-efficacy scales (specific and general) outcomes according to the athletes’ gender.<strong> </strong>Forty-three taekwondo athletes (33 male and 10 female) participated in this study. The Physical (PSE) and Specific (RKSES) self-efficacy scales were administered. Performance data (impact force and total response time) were acquired by athletes kicking twice to an instrumented target. Results showed that the specific self-efficacy scale has high reliability and is able to predict sport performance in males and females. Males had higher self-efficacy scores and also higher performance results than females. Females’ taekwondo psychological training should be focus on improving their self-efficacy perception in order to increase their performance in the roundhouse kick. This specific self-efficacy scale for the taekwondo roundhouse kick offers empirical information to coaches, sport psychologists and researchers that allow them to predict athletes’ sport performance in the roundhouse kick.


Author(s):  
Zhakiah Ahmed Amer

The objective of the current study was to detect the relationship between the qualitative differences between the creativity and the age of the student and the age of the parents at birth، family size، birth order، economic and cultural level، loss of parents and their habitat (environment) using the descriptive approach. A total of 953 students، from the first level (males and females) and from the scientific and literary colleges in Khartoum University، Sudan. The results showed no significant differences in creativity، no correlative between the age of the parents and the students' ages in creativity، but there are: - a negative correlative relationship with maternal age at level (0. 01) and a positive correlative relationship with the age of the students at the level (0. 01)، but in both flexibility and fluency، there is a negative correlation relationship statistically significant with the age of students at the level of (0. 01). There is no correlation between the creativity and birth order of the student، creativity and family size، negative correlative relation with family size at (0. 01). The differences in creativity could be attributed to the place of residence at a significant level (0. 01).  


2021 ◽  
Author(s):  
Tatiana S. Leite ◽  
Erica A.G. Vidal ◽  
Françoise Dantas Lima ◽  
Sergio M.Q. Lima ◽  
Ricardo M Dias ◽  
...  

Abstract The new species, Paroctopus cthulu sp. nov. Leite, Haimovici, Lima and Lima, was recorded from very shallow coastal waters on sandy/muddy and shelter-poor bottoms with natural and human-origin debris. It is a small octopus, adults are less than 35 mm mantle length (ML) and weigh around 15 g. It has short to medium sized arms, enlarged suckers on the arms of both males and females, large posterior salivary glands (25 %ML), a relatively large beak (9 % ML) and medium to large mature eggs (3.5 to > 9 mm). The characteristics of hatchlings of two brooding females, some of their anatomical features, and in-situ observations of their behaviour are a clue to the life history of it and closely related pygmy octopuses. The Bayesian phylogenetic analysis showed that Paroctopus cthulu sp.nov. specimens grouped in a well-supported clade of Paroctopus species, separate from P.joubini and P. cf mercatoris from the Northwestern Atlantic . The description of this new species, living in a novel habitat of human debris in shallow water off Brazil, offered an opportunity not only to evaluate the relationship among the small octopuses of the western Atlantic, Caribbean and eastern Pacific, but also their adaptation to the Anthropocene period.


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