scholarly journals Acanthocephalan size and sex affect the modification of intermediate host colouration

Parasitology ◽  
2009 ◽  
Vol 136 (8) ◽  
pp. 847-854 ◽  
Author(s):  
D. P. BENESH ◽  
O. SEPPÄLÄ ◽  
E. T. VALTONEN
Keyword(s):  
Intermediate Host ◽  
Adaptive Strategy ◽  
Female Size ◽  
Larval Size ◽  
Male And Female ◽  
Establishment Success ◽  
Acanthocephalus Lucii ◽  
Host Mortality ◽  
Male Parasite ◽  
The Relationship

SUMMARYFor trophically transmitted parasites, transitional larval size is often related to fitness. Larger parasites may have higher establishment success and/or adult fecundity, but prolonged growth in the intermediate host increases the risk of failed transmission via natural host mortality. We investigated the relationship between the larval size of an acanthocephalan (Acanthocephalus lucii) and a trait presumably related to transmission, i.e. altered colouration in the isopod intermediate host. In natural collections, big isopods harboured larger worms and had more modified (darker) abdominal colouration than small hosts. Small isopods infected with a male parasite tended to have darker abdominal pigmentation than those infected with a female, but this difference was absent in larger hosts. Female size increases rapidly with host size, so females may have more to gain than males by remaining in and growing mutually with small hosts. In experimental infections, a large total parasite volume was associated with darker host respiratory operculae, especially when it was distributed among fewer worms. Our results suggest that host pigment alteration increases with parasite size, albeit differently for male and female worms. This may be an adaptive strategy if, as parasites grow, the potential for additional growth decreases and the likelihood of host mortality increases.

The influence of Hymenolepis diminuta on the survival and fecundity of the intermediate host, Tribolium confusum

Parasitology ◽  
1980 ◽  
Vol 81 (2) ◽  
pp. 405-421 ◽  
Author(s):  
Anne E. Keymer
Keyword(s):  
Experimental Study ◽  
Intermediate Host ◽  
Parasite Burden ◽  
Tribolium Confusum ◽  
Hymenolepis Diminuta ◽  
Density Dependent ◽  
Host Mortality ◽  
Host Parasite ◽  
The Relationship ◽  
High Parasite

SUMMARYAn experimental study of the effects of parasitism by H. diminuta on the intermediate host, Tribolium confusum, is described. No density- dependent constraints on parasite establishment within individual hosts are evident, although a reduction in cysticercoid size at high parasite burdens is demonstrated. The relationship between parasite burden, host mortality and host fecundity is investigated. Host mortality is linearly related to parasite burden, whereas the relationship between parasite burden and host fecundity is non-linear. There is no difference in viability between eggs from infected and uninfected females. The generative causes of these effects are not investigated experimentally, although it is postulated that survival is related to the degree of damage to the midgut wall caused by parasite penetration, and fecundity to the biomass of parasites harboured by the host. The significance of these effects is discussed in relation to the overall dynamics of the host-parasite association.

Relationship between Faithfulness and Preference of Stars in a Planetarium

2019 ◽  
Vol 2 (1) ◽  
pp. 10402-1-10402-11
Author(s):  
Midori Tanaka ◽  
Takahiko Horiuchi ◽  
Ken’ichi Otani
Keyword(s):  
Light Source ◽  
Preference Rating ◽  
Experimental Procedure ◽  
Male And Female ◽  
Astronomical Observations ◽  
Low Luminance ◽  
Projection Pattern ◽  
The Relationship ◽  
Star Field

Abstract A planetarium imitates a starry sky with physical and technical limitations using a dome, projector, and light source. It is widely used for entertainment, and astronomy and physics educations. In our previous study, we investigated the evaluation for faithful reproduction of a star field in a planetarium by performing psychometric experiments with 20 observers for plural projection patterns with different reproduction factors (color, luminance, and size of projected stars). In this study, we investigate the relationship between faithfulness and preference of a star field in a planetarium through a psychometric experiment with 47 observers. The experimental procedure followed the previous study. The rating of faithfulness improved for the projection pattern with a smaller star size. For the preference evaluation, the projection pattern with low luminance significantly lowered the preference rating. The results of the experiment indicate that the preferable star reproduction was different between male and female observers, whereas the faithful star reproduction was not significantly different in the evaluations between male and female observers. The male observers sought a faithful star reproduction as the preferred reproduction. In contrast, the female observers did not feel the faithful star reproduction preferable, and evaluated the more brilliant star reproduction as the preferred reproduction. These results were not dependent on the experience in astronomical observations.

scholarly journals Complementary and Alternative Medicine Use among Norwegian Cancer Survivors: Gender-Specific Prevalence and Associations for Use

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Agnete E. Kristoffersen ◽  
Arne J. Norheim ◽  
Vinjar M. Fønnebø
Keyword(s):  
Cancer Survivors ◽  
Cancer Diagnosis ◽  
Health Issues ◽  
Men And Women ◽  
Male And Female ◽  
Factors Associated ◽  
Female Survivors ◽  
Cam Use ◽  
University Degree ◽  
The Relationship

The associations for CAM use are only occasionally differentiated by gender in populations where both male and female cancer survivors occur. The aim of this study is to describe the prevalence of CAM use in individuals with a previous cancer diagnosis and to investigate gender differences regard to factors associated with use. A total of 12982 men and women filled in a questionnaire with questions about life style and health issues. Eight hundred of those had a previous cancer diagnosis of whom 630 answered three questions concerning CAM use in the last 12 months. A total of 33.8% of all cancer survivors reported CAM use, 39.4% of the women and 27.9% of the men (). The relationship between the demographic variables and being a CAM user differed significantly between men and women with regard to age (), education (), and income (). Female CAM users were more likely to have a university degree than the nonusers, while male CAM users were more likely to have a lower income than the nonusers. According to this study, prevalence and factors associated with CAM use differ significantly between male and female survivors of cancer.

scholarly journals Relationship between Psychological Empowerment and Spiritual Intelligence with Marital Satisfaction in Female and Male Teachers in Ahvaz

2016 ◽  
Vol 12 (6) ◽  
pp. 132 ◽  
Author(s):  
Zahra Kordzangeneh ◽  
Hamdollah Jayervand
Keyword(s):  
Marital Satisfaction ◽  
Sampling Method ◽  
Psychological Empowerment ◽  
Pearson Correlation ◽  
Spiritual Intelligence ◽  
Step Method ◽  
Male And Female ◽  
Female Teachers ◽  
The Relationship ◽  
Coefficient Method

<p>The present study was aimed to examine the relationship between psychological empowerment and spiritual intelligence with marital satisfaction in male and female teachers in Ahvaz from 2014 to 2015. Hence, 350 teachers were selected using random-stratified sampling method. Research tools were Spriters' psychological empowerment questionnaire (1995), Badie's et al. spiritual intelligence questionnaire (2010), Enrich's marital satisfaction questionnaire (1997); in order to do analysis, a Pearson Correlation Coefficient method and a regression method was used. Results showed that there is a relationship between psychological empowerment and spiritual intelligence with marital satisfaction in male and female teachers in Ahvaz. The results obtained from multi-fold regression analysis, using step-by-step method, showed that effectiveness, spiritual intelligence, and significance are able to predict marital satisfaction significantly. In addition, psychological empowerment has a closer relationship with spiritual intelligence, and spiritual intelligence has a closer relationship with marital satisfaction. </p>

scholarly journals The Relationship Between Trauma, Recidivism Risk, and Reoffending in Male and Female Juvenile Offenders

2018 ◽  
Vol 12 (3) ◽  
pp. 351-364 ◽  
Author(s):  
Nina A. Vitopoulos ◽  
Michele Peterson-Badali ◽  
Shelley Brown ◽  
Tracey A. Skilling
Keyword(s):  
Juvenile Offenders ◽  
Female Juvenile Offenders ◽  
Male And Female ◽  
Trauma Recidivism ◽  
The Relationship

The Relationship between Psychological Skills, Experience, and Practice Commitment among Collegiate Male and Female Skiers

1993 ◽  
Vol 7 (1) ◽  
pp. 49-57 ◽  
Author(s):  
Sally A. White
Keyword(s):  
Psychometric Properties ◽  
Gender Effect ◽  
Psychological Skills ◽  
Internal Reliability ◽  
Male And Female ◽  
Mental Preparation ◽  
The Social ◽  
And Gender ◽  
The Relationship

The Psychological Skills Inventory for Sport (PSIS; Mahoney, 1988) identifies certain psychological skills or characteristics possessed by successful athletes. However, little has been done to connect the PSIS with other variables that may have an impact on the athletes’ psychological skills. Therefore the purpose of this study was twofold. First, the psychometric properties of the PSIS for all subjects and by gender were determined. Second, the relationship between the PSIS, experience, practice commitment, and gender of collegiate skiers was examined. A random sample of 131 male and female collegiate skiers responded to the 45-item PSIS. Overall, the six PSIS subscales (anxiety, concentration, confidence, mental preparation, motivation, and team emphasis) demonstrated acceptable internal reliability (coeff. alpha = .69−.84). Results of a 4 × 3 × 2 (Experience × Practice Commitment × Gender) MANOVA and follow-up univariate F tests revealed a significant gender effect on the team emphasis subscale. Female collegiate skiers were more team oriented than male collegiate skiers and placed more importance on the social and affiliative aspects of being on a team than did their male counterparts.

scholarly journals Association between Foot Posture Index and Ankle Sprain in Indoor Football Players

2016 ◽  
Vol 8 (10) ◽  
pp. 160 ◽  
Author(s):  
Afsaneh Safar Cherati ◽  
Masoud Dousti ◽  
Shima Younespour
Keyword(s):  
Ankle Sprain ◽  
Football Players ◽  
Male And Female ◽  
Positive History ◽  
Foot Posture Index ◽  
Posture Index ◽  
Foot Posture ◽  
History Of ◽  
The Relationship

<p><strong>Objective</strong><strong>: </strong>This study investigated the relationship between foot type and ankle sprain incidence.</p><p><strong>Method</strong><strong>: </strong>In a prospective cohort study using the FPI, 68 adult male and female indoor football (Futsal) players were measured and their feet were classified according to foot posture index (FPI) as neutral, supinated and pronated. They were followed over 6 month as a one competition season and at the end, any injuries at the ankle during this period were detected.</p><p><strong>Result</strong><strong>: </strong>There was no significant association between FPI score (considering the total FPI score and its six components) and occurrence of ankle sprain. Also, no association was existed between gender, age, height, weight, BMI, duration of professional exercise, dominant foot and occurrence of ankle sprain. In this study, the history of previous ankle sprain was the only significant predictor of the occurrence of ankle sprain in the follow-up period. Participants with the positive history of previous ankle sprain were at higher risk of developing new ankle sprain (OR=6.02, 95% CI: (1.93, 18.84), p=0.002).</p><p><strong>Conclusion</strong><strong>: </strong>There was no significant association between FPI score and occurrence of ankle sprain.<strong></strong></p><p><strong>Limitation: </strong>there was scarce of supinated foot in the study so evaluation of relationship between supinated feet and ankle sprain was not applicable.</p>

THE RELATIONSHIP BETWEEN SERUM TESTOSTERONE LEVELS, SEX AND TEAT-SEEKING ABILITY OF NEWBORN PIGLETS

1985 ◽  
Vol 65 (3) ◽  
pp. 627-630 ◽  
Author(s):  
L. A. BATE ◽  
R. R. HACKER ◽  
M. B. KREUKNIET
Keyword(s):  
Body Weight ◽  
Detrimental Effect ◽  
Serum Testosterone ◽  
Maternal Serum ◽  
Blood Samples ◽  
Male And Female ◽  
Newborn Piglets ◽  
Baseline Levels ◽  
Highly Correlated ◽  
The Relationship

Blood samples were collected from five pregnant sows from day 111 postbreeding to farrowing and from their piglets at regular intervals between birth and 48 h. The time between birth and first suckling (BTS) was recorded for each piglet. Maternal serum testosterone (T) levels were detectable only at the beginning of parturition and were highly correlated (r = 0.83) with litter BTS. Serum T levels of male and female piglets were similar at birth. In male piglets the T levels increased to a peak 2 h after birth and decreased gradually thereafter. In contrast, the T levels of female piglets declined rapidly after birth to baseline levels. The BTS of female piglets was shorter than that of male piglets. Body weight of males was higher than that of females and was influenced by litter size. These results suggest that the higher serum T levels of male piglets may have a detrimental effect on their teat-seeking ability. Key words: Serum testosterone, sex, piglets, teat-seeking ability, sow

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