scholarly journals Food ingestion and assimilation by Hyale media (Dana, 1853) (Crustacea - Amphipoda)

1990 ◽  
Vol 38 (1) ◽  
pp. 11-21 ◽  
Author(s):  
Airton Santo Tararam ◽  
Hilda de Souza Lima Mesquita ◽  
Yoko Wakabara ◽  
Clóvis A Peres
Keyword(s):  
Developmental Stages ◽  
Specific Growth ◽  
Assimilation Efficiency ◽  
Effect Of Temperature ◽  
Adult Males ◽  
Food Ingestion ◽  
Young Males ◽  
Physiological Conditions ◽  
Winter Temperatures ◽  
Summer Temperatures

The feeding of Hyale media was analysed under laboratory conditions in winter and summer temperatures. The results showed that assimilation rates increased following food ingestion rates and decreased when egestion rates increased. In winter temperatures no significant differences were found in the assimilation rates among developmental stages and sexes. In summer temperatures assimilation rates for ovigerous and non-ovigerous females were higher than those found for adult and young males. Although not statistically analysed, mean assimilation efficiencies were highest among ovigerous females and adult males, in summer. The quantitative and qualitative variations found in the assimilation efficiency and rates were explained by the differential effect of temperature on the specific growth rate and in the physiological conditions of each growth stage concerned.

Effect of temperature on physiology and bioenergetics of adult Harris mud crab Rhithropanopeus harrisii (Gould, 1841) from the southern Baltic Sea

2014 ◽  
Vol 43 (3) ◽  
Author(s):  
Joanna Hegele-Drywa ◽  
Monika Normant
Keyword(s):  
Production Efficiency ◽  
Assimilation Efficiency ◽  
Ammonia Excretion ◽  
Point Of View ◽  
Effect Of Temperature ◽  
Adult Males ◽  
Mud Crab ◽  
Rhithropanopeus Harrisii ◽  
Physiological Processes ◽  
Food Assimilation

AbstractRates of physiological processes and bioenergetics of the Harris mud crab Rhithropanopeus harrisii were determined during a 7-day experiment on adult males (mean wet weight 0.83 ± 0.16 g) exposed to temperatures of 15°C and 20°C (S = 7). The results show that the change in temperature by 5°C caused detectable changes in locomotor activity, food consumption and faeces production and significant (p < 0.05) changes in metabolic rates. Food assimilation efficiency and the ammonia excretion rate did not change significantly (p > 0.05). The energy expended on metabolic processes was similar at both temperatures (15°C and 20°C) and amounted to 17.7 ± 6.4% and 16.7 ± 4.3% of the assimilated energy, respectively. Similar values were obtained for net production efficiency K2 (P/A) at 15°C and 20°C, i.e. 80.4 ± 22.4% and 82.9 ± 9.7%, respectively. The amount of energy available for production was 2-fold higher at a temperature of 20°C than at 15°C and amounted to 103.69 ± 25.61 and 206.40 ± 20.76 J d−1g−1 wet wt, respectively. The results show that from the bioenergetic point of view, higher experimental temperature is more “profitable” for adult R. harrisii specimens because it provides better conditions for the growth and reproduction.

Effect of temperature and light on germination of 10 species of Eucalyptus from north-western NSW

2018 ◽  
Vol 66 (8) ◽  
pp. 657 ◽  
Author(s):  
Lorena Ruiz-Talonia ◽  
David Carr ◽  
Rhiannon Smith ◽  
R. D. B. Whalley ◽  
Nick Reid
Keyword(s):  
Germination Percentage ◽  
Effect Of Temperature ◽  
Eucalyptus Species ◽  
Continuous Darkness ◽  
Native Communities ◽  
South Wales ◽  
Treatment Conditions ◽  
Winter Temperatures ◽  
Summer Temperatures ◽  
North Western

The effects of temperature and light were examined on the germination of 14 seedlots of 10 Eucalyptus species, which are important for revegetation of native communities in north-western New South Wales. The species tested were E. albens, E. blakelyi, E. chloroclada, E. dealbata, E. camaldulensis, E. melanophloia, E. melliodora, E. pilligaensis, E. populnea and E. sideroxylon. Species were subjected to three alternating day/night temperatures (15/5, 25/15 and 35/25°C), representing winter, spring/autumn and summer conditions, respectively, and two light treatments (light/dark or dark), in growth cabinets. Limited quantities of seed of most seedlots prevented full factorial combinations of most treatments. Overall germination was high but varied significantly between species and seedlots within species. Differences were small, but light combined with winter or spring/autumn temperatures resulted in higher average germination (96%) than darkness and summer temperatures (93%). Seedlots of E. chloroclada, E. blakelyi, E. camaldulensis, E. sideroxylon, E. melliodora and E. melanophloia germinated consistently well under all treatment conditions, whereas germination in seedlots of E. albens, E. dealbata, E. melliodora, E. pilligaensis and E. populnea varied with treatments. Germination of small seeds was higher in the presence of light whereas larger seeds germinated better in continuous darkness. The time to first germination was three times faster under summer and spring/autumn temperatures than winter temperatures. In conclusion, temperature and light can significantly impact germination percentage and rate, depending on the species and provenances, and therefore should be considered in planning restoration projects in both nursery and field.

scholarly journals Correlates and Treatment Outcome of Risky Sexual Behaviour in Young Males with ADHD and Comorbid Alcohol Use Disorder: A Prospective Study

2019 ◽  
Vol 1 (1) ◽  
pp. 62-69
Author(s):  
Shankar Kumar ◽  
Yamini Devendran ◽  
Madhumitha N. S. ◽  
Javagal Amith Thejas
Keyword(s):  
Sexual Behavior ◽  
Alcohol Use ◽  
Perceived Stress ◽  
Risky Sexual Behavior ◽  
Alcohol Use Disorder ◽  
Self Report ◽  
Adult Males ◽  
Young Males ◽  
Severity Scores ◽  
Inattention And Hyperactivity

Background: Attention-deficit/hyperactivity disorder (ADHD) is associated with risky sexual behavior (RSB). Alcohol use and high perceived stress in young adulthood contributes to this association. Previous studies have not found methylphenidate to reduce RSB in ADHD, as the population had comorbidities such as mood disorders and antisocial personality disorder. We aimed to study (a) the association of RSB with ADHD and severity of alcohol use among adolescents and young adult males with ADHD who had comorbid alcohol use disorder and (b) the effect of treatment of ADHD using methylphenidate on RSB in this population at 3- and 6-month follow-ups. Methodology: The study had 31 participants who were selected by screening for RSBs using the sexual behavior section of the HIV Risk-taking Behavior Scale (HRBS) manual among a cohort of individuals with ADHD and early onset alcohol use. These individuals were also administered WHO ADHD self-report scale (ASRS), alcohol-use disorders identification test (AUDIT), perceived stress scale (PSS), and HRBS-sexual behavior section. They were then treated with methylphenidate and these assessments were repeated at 3 and 6 months. Results: Those having ADHD with RSB had higher total ADHD score ( P = .007) and inattention score ( p = .0001) than those without RSB. There was a significant correlation between the ADHD total score with alcohol-use severity ( r = 0.47), with RSB ( r = 0.34), and ADHD hyperactivity scores with alcohol-use severity ( r = 0.49) and with RSB ( r = 0.34). There was also a significant reduction of ADHD total, inattention and hyperactivity scores, alcohol-use severity scores, RSB and perceived stress scores with use of methylphenidate at 3- and 6-month follow-ups. Multiple logistic regression predicted reduction in ADHD total scores to reduce RSB (odds ratio [OR] = 1.26, P = .01). Conclusion: RSB was associated with severity of ADHD and alcohol use. Methylphenidate not only reduced ADHD severity but also alcohol-use severity and RSB, whose reduction was predicted by reduction in ADHD severity.

scholarly journals Relating Reactive and Proactive Aggression to Trait Driving Anger in Young and Adult Males: A Pilot Study Using Explicit and Implicit Measures

2021 ◽  
Vol 13 (4) ◽  
pp. 1850
Author(s):  
Veerle Ross ◽  
Nora Reinolsmann ◽  
Jill Lobbestael ◽  
Chantal Timmermans ◽  
Tom Brijs ◽  
...  
Keyword(s):  
Pilot Study ◽  
Cognitive Biases ◽  
Young Male ◽  
Proactive Aggression ◽  
Implicit Measures ◽  
Adult Males ◽  
Young Males ◽  
Targeted Interventions ◽  
Driving Anger ◽  
Reactive And Proactive Aggression

Driving anger and aggressive driving are main contributors to crashes, especially among young males. Trait driving anger is context-specific and unique from other forms of anger. It is necessary to understand the mechanisms of trait driving anger to develop targeted interventions. Although literature conceptually distinguished reactive and proactive aggression, this distinction is uncommon in driving research. Similar, cognitive biases related to driving anger, measured by a combination of explicit and implicit measures, received little attention. This pilot study related explicit and implicit measures associated with reactive and proactive aggression to trait driving anger, while considering age. The sample consisted of 42 male drivers. The implicit measures included a self-aggression association (i.e., Single-Target Implicit Association Test) and an attentional aggression bias (i.e., Emotional Stroop Task). Reactive aggression related positively with trait driving anger. Moreover, a self-aggression association negatively related to trait driving anger. Finally, an interaction effect for age suggested that only in young male drivers, higher proactive aggression related to lower trait driving anger. These preliminary results motivate further attention to the combination of explicit and implicit measures related to reactive and proactive aggression in trait driving anger research.

scholarly journals Effect of Temperature on the Development and Survival of Feltiella Acarisuga (Vallot) (Diptera: Cecidomyiidae) Preying on Tetranychus Urticae (Koch) (Acari: Tetranychidae)

Insects ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 508
Author(s):  
Yong-Seok Choi ◽  
Sung-Hoon Baek ◽  
Min-Jung Kim
Keyword(s):  
Developmental Stages ◽  
Gall Midge ◽  
Mass Rearing ◽  
Immature Stage ◽  
Development Rate ◽  
Effect Of Temperature ◽  
Thermal Constant ◽  
Fundamental Information ◽  
Threshold Temperatures ◽  
Response To Temperature

The predatory gall midge, Feltiella acarisuga (Vallot) (Diptera: Cecidomyiidae), is an acarivorous species that mainly feeds on spider mites (Acarina: Tetranychidae). Because of its cosmopolitan distribution and predation efficacy, it is considered an important natural enemy available as a biological agent for augmentative biocontrol. However, despite its practical use, the thermal development and survival response to temperature have not yet been fully studied. In this study, we investigated the stage-specific development and survival of F. acarisuga at seven temperatures (11.5, 15.7, 19.8, 23.4, 27.7, 31.9, and 35.4 °C) to examine the effect of temperature on its lifecycle. All developmental stages could develop at 11.5–31.9 °C, but the performance was different according to the temperature. From the linear development rate models, the lower development threshold and thermal constant of the total immature stage were estimated at 8.2 °C and 200 DD, respectively. The potential optimal and upper threshold temperatures for the total immature stage were estimated as 29.3 and 35.1 °C using a non-linear development model. The operative thermal ranges for development and survival at 80% of the maximum rate were 24.5–32.3 and 14.7–28.7 °C, respectively. Thus, it was suggested that 24.5–28.7 °C was suitable for the total immature stage. In contrast, conditions around 8 °C and 35 °C should be avoided due to the lower development rate and high mortality. Our findings provide fundamental information for an effective mass-rearing and releasing program of F. acarisuga in an augmentative biocontrol program and help to predict phenology.

Dispersal patterns in a regional koala population in south-east Queensland

2003 ◽  
Vol 30 (3) ◽  
pp. 281 ◽  
Author(s):  
David S. Dique ◽  
Jim Thompson ◽  
Harriet J. Preece ◽  
Deidré L. de Villiers ◽  
Frank N. Carrick
Keyword(s):  
Urban Areas ◽  
Home Ranges ◽  
Adult Males ◽  
Dispersal Patterns ◽  
Young Males ◽  
Straight Line ◽  
The Social ◽  
Straight Line Distance ◽  
Males And Females ◽  
Natal Home

Koala dispersal was investigated as part of a detailed ecological study of a nationally significant koala population located 20 km south-east of Brisbane, Queensland. From 1996 to 2000, 195 koalas from three sites were captured and fitted with radio-collars. A total of 40 koalas (23 males and 17 females) dispersed from these sites. Most (93%) dispersing individuals were 20–36 months of age. Three adult females (more than 36 months old) dispersed and no adult males dispersed during the study. A significantly higher proportion of young males dispersed than females. Dispersal occurred between June and December, with most dispersal of males commencing in July and August and that of females commencing between September and November prior to, and early in, the annual breeding season. The mean straight-line distance between the natal and breeding home ranges for males and females was similar and was measured at 3.5 km (range 1.1–9.7 km) and 3.4 km (range 0.3–10.6 km) respectively. Dispersing males and females tended to successfully disperse south and west of their natal home ranges and were generally unable to successfully disperse to urban areas within the study area, as a high proportion of the mortality of dispersing koalas was associated with attacks by domestic dogs and with collisions with vehicles on roads. Information from other studies indicates that most young koalas disperse from their natal areas. It is likely that the social behaviour and mating systems of koala populations provide mechanisms for young koalas to disperse. The potential role of dispersal in the dynamics of regional koala populations is discussed.

scholarly journals Effect of Ambient Temperature on Daily Nebulized Asthma Hospital Visits in a Tropical City of Dhaka, Bangladesh

2021 ◽  
Vol 18 (3) ◽  
pp. 890
Author(s):  
Ayesha Ferdosi Kabir ◽  
Chris Fook Sheng Ng ◽  
Shinya Yasumoto ◽  
Taiichi Hayashi ◽  
Chiho Watanabe
Keyword(s):  
Positive Association ◽  
The Elderly ◽  
Acute Effect ◽  
Effect Of Temperature ◽  
Inverse Association ◽  
Adult Males ◽  
Asthma Morbidity ◽  
Delayed Effects ◽  
Asthma Patients ◽  
Hospital Visits

The acute effect of temperature on asthma morbidity in Bangladesh is not well understood. As climate varies extensively in different parts of the world, the relation between temperature and asthma might also differ. We investigated the association between temperature and asthma-related hospital visits in the tropical city of Dhaka. We analyzed information from a total of 5989 asthma patients who received ambulatory care in the form of nebulized medication at the National Asthma Center in Mohakhali, Dhaka from February to November 2013. A time-stratified case-crossover study was conducted to estimate the effect of daily temperature, with consideration of delayed effects and possible confounders such as relative humidity and political strikes. An inverse association was observed between temperature and the number of hospital visits. The effect was delayed for approximately a week. A degree centigrade decrease in mean temperature (averaged across lags 0-6) was associated with an increase of approximately 4.5% (95% CI 1.5, 7.5) in all asthma visits. The association was evident in adult males but marginal in elderly males. A positive association (lag 0) was observed among adult females, whereas no association was observed among children. Strikes significantly modified the effect among the elderly. Findings suggest temperature declines affect asthma outcomes in a warm climate, and this effect can be delayed and vary by sex and age group.

Extrinsic Inter- and Intra-specific Competition in Parasitoid Wasps

2021 ◽  
Vol 67 (1) ◽  
Author(s):  
Paul J. Ode ◽  
Dhaval K. Vyas ◽  
Jeffrey A. Harvey
Keyword(s):  
Developmental Stages ◽  
Interference Competition ◽  
Apparent Competition ◽  
Annual Review ◽  
Publication Date ◽  
Natural Ecosystem ◽  
Adult Males ◽  
Alternate Host ◽  
Adult Females ◽  
Behavioral Mechanisms

The diverse ecology of parasitoids is shaped by extrinsic competition, i.e., exploitative or interference competition among adult females and males for hosts and mates. Adult females use an array of morphological, chemical, and behavioral mechanisms to engage in competition that may be either intra- or interspecific. Weaker competitors are often excluded or, if they persist, use alternate host habitats, host developmental stages, or host species. Competition among adult males for mates is almost exclusively intraspecific and involves visual displays, chemical signals, and even physical combat. Extrinsic competition influences community structure through its role in competitive displacement and apparent competition. Finally, anthropogenic changes such as habitat loss and fragmentation, invasive species, pollutants, and climate change result in phenological mismatches and range expansions within host–parasitoid communities with consequent changes to the strength of competitive interactions. Such changes have important ramifications not only for the success of managed agroecosystems, but also for natural ecosystem functioning. Expected final online publication date for the Annual Review of Entomology, Volume 67 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Further Observations on the Morphology of Heterodera schachtii, with Remarks on the Bionomics of a strain attacking Mangolds in Britain

1929 ◽  
Vol 7 (3) ◽  
pp. 119-140 ◽  
Author(s):  
Marjorie J. Triffitt
Keyword(s):  
Sugar Beet ◽  
Developmental Stages ◽  
Morphological Characters ◽  
Heterodera Schachtii ◽  
Adult Males ◽  
Morphological Variations ◽  
Size And Shape ◽  
Morphological Studies ◽  
Comparative Survey

In a previous publication the morphological characters of a strain of H. schachtii specialised on the potato in Lincolnshire were discussed. The size and shape of the brown cysts, size of the eggs and first stage larvæ and the general characters of the adult males of this strain were compared with those of a strain attacking potatoes in Rostock, Mecklenburg, for which the specific name H. rostochiensis was suggested by Wollenweber 1923.Considerable dimensional variations were found to exist in the Lincolnshire strain, and a study of the literature on the morphological characters of H. schachtii specialised on sugar-beet and oats, showed equally wide divergencies between the findings of different workers. A certain amount of preserved material of infected roots of beet and oats being available to the writer, as many developmental stages as possible were extracted from these, on which similar morphological studies were carried out. Thus a fairly complete comparative survey of H. schachtii specialised on beet, oats and potatoes was completed, and the morphological variations between the strains were found to be insufficient to justify the separation of the strain specialised on potato from those on beet and oats. The name H. rostochicnsis was, therefore, deemed a synonym for H. schachtii.

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