scholarly journals Sex Differences in Forebrain Monoaminergic Response to Song Performance

2017 ◽  
Vol 89 (3) ◽  
pp. 219-230 ◽  
Author(s):  
Susan M. Lyons ◽  
Keith W. Sockman

In many species, successful reproduction is dependent on the ability to adjust social behavior in response to an ever-changing social environment. Because a sexual signal's value and meaning can differ between females and males, responses to those signals should also differ. One way individuals can modulate social behavior is through experience-dependent modulation of the sensory systems that process social signals. Central monoamines (norepinephrine, dopamine, serotonin) modulate neural sensitivity to social stimuli and are key regulators of experience-dependent neuroplasticity in vertebrate sensory systems. However, few studies have examined how exposure to different sexual signals influences monoaminergic activity in female compared to male sensory systems. We used Lincoln's sparrows (Melospiza lincolnii) to examine sex differences in how variation in the trill performance of song influences central monoaminergic activity in the auditory telencephalon. Trill performance measures the rate at which a song syllable is produced relative to the syllable's frequency bandwidth and is thought to reflect the difficulty with which songs are produced. High-performance trills are more threatening to males but more attractive to females. We found that the effects of trill performance on monoaminergic activity were sex-dependent. Relative to the response to low-performance songs, exposure to high-performance songs decreased noradrenergic activity in the caudomedial nidopallium, and tended to decrease serotoninergic activity in the caudomedial mesopallium and caudomedial nidopallium of the auditory telencephalon in females, but in males, the monoamine measurements were indistinguishable between song treatments. These results suggest that the mechanisms underlying sensory processing of male sexual signals differ between the sexes.

2014 ◽  
Vol 10 (10) ◽  
pp. 20140588 ◽  
Author(s):  
Susan M. Lyons ◽  
Michaël Beaulieu ◽  
Keith W. Sockman

Animals do not make decisions in a bubble but often refer to previous experience when discriminating between options. Contrast effects occur when the value of a stimulus affects the response to another value of the stimulus, and the changes in value and response are in the same direction. Although contrast effects appear irrational, they could benefit decision makers when there is spatial or temporal variation and autocorrelation in the value of stimuli that elicit decisions. Here, we examined whether contrasts influence female evaluation of male performance-based sexual signals. We exposed female Lincoln's sparrows ( Melospiza lincolnii ) to one week of songs that we had experimentally reduced or elevated in performance, followed by a novel song of intermediate performance. We found that high-performance songs were more attractive to females than low-performance songs. Moreover, the intermediate songs were more attractive following exposure to low- than to high-performance songs. These results indicate that contrast can influence evaluation of performance-based sexual stimuli. By examining contrast effects in the ecologically relevant context of mate choice for performance, we can better understand both the adaptive value of comparative evaluation as well as the mechanisms that underlie variation in mate choice and sexual selection.


2006 ◽  
Vol 274 (1611) ◽  
pp. 771-778 ◽  
Author(s):  
Torsten Nygaard Kristensen ◽  
Volker Loeschcke ◽  
Ary A Hoffmann

Artificially selected lines are widely used to investigate the genetic basis of quantitative traits and make inferences about evolutionary trajectories. Yet, the relevance of selected traits to field fitness is rarely tested. Here, we assess the relevance of thermal stress resistance artificially selected in the laboratory to one component of field fitness by investigating the likelihood of adult Drosophila melanogaster reaching food bait under different temperatures. Lines resistant to heat reached the bait more often than controls under hot and cold conditions, but less often at intermediate temperatures, suggesting a fitness cost of increased heat resistance but not at temperature extremes. Cold-resistant lines were more common at baits than controls under cold as well as hot field conditions, and there was no cost at intermediate temperatures. One of the replicate heat-resistant lines was caught less often than the others under hot conditions. Direct and correlated patterns of responses in laboratory tests did not fully predict the low performance of the heat selected lines at intermediate temperatures, nor the high performance of the cold selected lines under hot conditions. Therefore, lines selected artificially not only behaved partly as expected based on laboratory assays but also evolved patterns only evident in the field releases.


1973 ◽  
Vol 36 (3) ◽  
pp. 735-738 ◽  
Author(s):  
Joaquin F. Sousa-Poza ◽  
Robert Rohrberg ◽  
Ernest Shulman

Some characteristics of the social behavior of field-dependents as well as their superior recognition of ambiguous social stimuli led to the hypothesis that they would show greater self-disclosure than field-independents. This hypothesis was tested by administering the 60-item Jourard Self-disclosure Questionnaire (JSDQ) to 13 field-dependent and 13 field-independent Ss. In terms of total self-disclosure scores, field-dependents showed significantly (.025) higher levels than field-independents. Results are discussed in light of personality theories which emphasize the role of self-conceptual transactions in the development of the self.


2013 ◽  
Vol 30 (06) ◽  
pp. 1350026 ◽  
Author(s):  
ADIEL TEIXEIRA DE ALMEIDA

Using additive models for aggregation of criteria is an important procedure in many multicriteria decision methods. This compensatory approach, which scores the alternatives straightforwardly, may have significant drawbacks. For instance, the Decision Maker (DM) may prefer not to select alternatives which have a very low performance in whatever criterion. In contrast, such an alternative may have the best overall evaluation, since the additive model may compensate this low performance in one of the criteria as a result of high performance in other criteria. Thus, additive-veto models are proposed with a view to considering the possibility of vetoing alternatives in such situations, particularly for choice and ranking problems. A numerical application illustrates the use of such models, with a detailed discussion related to real practical problems. Moreover, the results obtained from a numerical simulation show that it is not so rare for a veto of the best alternative to occur in the additive model. This is of considerable relevance depending on the DM's preference structure.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chia-Wei Li ◽  
Carol Yeh-Yun Lin ◽  
Ting-Ting Chang ◽  
Nai-Shing Yen ◽  
Danchi Tan

AbstractManagers face risk in explorative decision-making and those who are better at such decisions can achieve future viability. To understand what makes a manager effective at explorative decision-making requires an analysis of the manager’s motivational characteristics. The behavioral activation/inhibition system (BAS/BIS), fitting the motivational orientation of “approach” or “avoidance,” can affect individual decision-making. However, very little is known about the neural correlates of BAS/BIS orientation and their interrelationship with the mental activity during explorative decision-making. We conducted an fMRI study on 111 potential managers to investigate how the brain responses of explorative decision-making interact with BAS/BIS. Participants were separated into high- and low-performance groups based on the median exploration-score. The low-performance group showed significantly higher BAS than that of the high-performance group, and its BAS had significant negative association with neural networks related to reward-seeking during explorative decision-making. Moreover, the BIS of the low-performance group was negatively correlated with the activation of cerebral regions responding to risk-choice during explorative decision-making. Our finding showed that BAS/BIS was associated with the brain activation during explorative decision-making only in the low-performance group. This study contributed to the understanding of the micro-foundations of strategically relevant decision-making and has an implication for management development.


Author(s):  
Adam G. Pautsch ◽  
Arun Gowda ◽  
Ljubisa Stevanovic ◽  
Rich Beaupre

In the continuing effort to alleviate the increasing thermal loads for power electronics devices, numerous aggressive solutions have been developed, such as small-scale micro-channel heat exchangers. Although these methods can improve overall surface heat transfer to the order of 500 W cm−2, they are limited to single-sided cooling due to the typical wire-bonded electrical connections of the devices. Power overlay (POL) technology provides a stable planar structure for electrical connection, as well as attachment of an additional top-side heat exchanger. This study presents an analysis of double-sided microchannel cooling of a power electronics module. Two optimized, integral micro-channel heat sinks were attached above and below silicon power devices, with more traditional attachment on one side and a POL interface on the other. A compliant TIM was selected for low thermal resistance and good mechanical response, which allowed top-side connection to the POL surface. A theoretical model is presented that predicts the benefit of double-sided cooling based on the known performance of a single-sided heat sink and given addition thermal contact resistance for the top side. For microchannels with water, an enhancement of 26% was predicted. An experiment was also carried out to measure the actual performance benefit seen with double-sided cooling. An enhancement of over 30% was measured for a particular design. As the theory predicts, the benefit of double-sided cooling is limited for high performance designs. However, double-sided cooling could lead to high levels of thermal performance using low-performance technology.


2018 ◽  
Vol 89 (16) ◽  
pp. 3244-3259 ◽  
Author(s):  
Sumit Mandal ◽  
Simon Annaheim ◽  
Andre Capt ◽  
Jemma Greve ◽  
Martin Camenzind ◽  
...  

Fabric systems used in firefighters' thermal protective clothing should offer optimal thermal protective and thermo-physiological comfort performances. However, fabric systems that have very high thermal protective performance have very low thermo-physiological comfort performance. As these performances are inversely related, a categorization tool based on these two performances can help to find the best balance between them. Thus, this study is aimed at developing a tool for categorizing fabric systems used in protective clothing. For this, a set of commercially available fabric systems were evaluated and categorized. The thermal protective and thermo-physiological comfort performances were measured by standard tests and indexed into a normalized scale between 0 (low performance) and 1 (high performance). The indices dataset was first divided into three clusters by using the k-means algorithm. Here, each cluster had a centroid representing a typical Thermal Protective Performance Index (TPPI) value and a typical Thermo-physiological Comfort Performance Index (TCPI) value. By using the ISO 11612:2015 and EN 469:2014 guidelines related to the TPPI requirements, the clustered fabric systems were divided into two groups: Group 1 (high thermal protective performance-based fabric systems) and Group 2 (low thermal protective performance-based fabric systems). The fabric systems in each of these TPPI groups were further categorized based on the typical TCPI values obtained from the k-means clustering algorithm. In this study, these categorized fabric systems showed either high or low thermal protective performance with low, medium, or high thermo-physiological comfort performance. Finally, a tool for using these categorized fabric systems was prepared and presented graphically. The allocations of the fabric systems within the categorization tool have been verified based on their properties (e.g., thermal resistance, weight, evaporative resistance) and construction parameters (e.g., woven, nonwoven, layers), which significantly affect the performance. In this way, we identified key characteristics among the categorized fabric systems which can be used to upgrade or develop high-performance fabric systems. Overall, the categorization tool developed in this study could help clothing manufacturers or textile engineers select and/or develop appropriate fabric systems with maximum thermal protective performance and thermo-physiological comfort performance. Thermal protective clothing manufactured using this type of newly developed fabric system could provide better occupational health and safety for firefighters.


Holzforschung ◽  
2018 ◽  
Vol 73 (1) ◽  
pp. 117-130 ◽  
Author(s):  
Vebi Mimini ◽  
Vasken Kabrelian ◽  
Karin Fackler ◽  
Hubert Hettegger ◽  
Antje Potthast ◽  
...  

AbstractThe bulk use of renewable polymers is currently largely limited to cellulose and, less significantly, hemicelluloses. Technical lignins are only applied in novel materials to a rather limited extent, although bulk lignin utilization is a worldwide research object. Native lignins, which belong to the second or third most abundant biopolymers of terrestrial plants, are mostly used in the form of technical lignins from wood pulping processes; they are employed in low-performance sectors or simply burnt for the generation of energy. Technical lignins are available in huge quantities and have a large application potential, mainly in areas where their aromatic nature is of relevance. This review presents the state of the art of foamed lignin-based polymers (lignofoams) as high-performance insulation materials. In the focus of this presentation are the fundamental foaming principles and influential agents that have an improvement potential concerning the matrix interactions between technical lignins (including lignosulfonates) and a copolymer in foam composites. The different approaches for foam preparation are critically compared. In general, the reviewed papers disclose that the lignin part in foams should be less than 37%. There are significant difficulties to improve the properties of lignofoams, and thus intensive research is needed to find better formulations and new technologies.


2018 ◽  
Vol 2 (3) ◽  
pp. 112
Author(s):  
Amal Ahmed Abdou ◽  
Iman Osama Abd El Gwad ◽  
Ayman Alsayed Altaher Mahmoud

Egyptian universities had the most powerful buildings that encourage sustainable development. Sustaining university buildings had been the main concern, thus the development focused on different aspects (social, sociological, bio-life, physical, healthy surroundings, etc.). In recent times, the main problem facing university buildings has been the high consumption of energy despite the low performance. This problem affected the interior areas and spaces used by the majority of students. The issue hindered the learning environment—which should be designed to facilitate high academic performance—from achieving its purpose. Fixing the problem required finding the errors applied in the planning policy, in order to integrate low energy consumption with high performance. This paper analyzes the design strategy, low energy design strategy, and its analysis systems in order to integrate them with the analysis of four case studies in comparative methodology. This approach helps in achieving effective observation to implement principles, policy, criteria, and strategies. The method of the paper shall help with coming up with an efficient vision to create the integrated design strategy for constructing university buildings in Egypt. The solution is characterized by low-cost energy consumption that is applicable to the conditions in Egypt and is in synchronization with sustainability as a whole vision.


Author(s):  
G. Trittler ◽  
E. Eckert ◽  
M. Göing

Hypersonic aircraft projects are highly dependant on efficient propulsion systems. High performance and integration within the airframe play a vital role in the overall concept. Particular attention must be paid to the exhaust system that is submitted to a wide range of operational requirements. An optimization of the nozzle geometry for high flight Mach numbers will lead to a low performance at the transonic flight regime. The additional use of secondary ejector air flow at transonic speeds is one option to improve the thrust behaviour of the nozzle. In the presented paper performance data of single expansion ramp ejector type nozzles are predicted using a calculation model based on a method-of-characteristics algorithm. For optimization purposes the effects of various design parameters on axial thrust coefficient and thrust vector angle are discussed. The geometric parameters investigated are the length of the lower nozzle wall and its deflection angle as well as the ejector slot location and its cross-section.


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