Testosterone And Interpersonal Attraction: A Placebo-Controlled Design

Testosterone has long been implicated as a neuroendocrinological mechanism in the expression of reproductive strategies. Humans the world over form and maintain pair-bonds suggesting that pair-bonds may serve to enhance reproductive fitness. However, infidelity is a perennial threat to these bonds. The data in humans suggests that testosterone is associated with mate-seeking but may be detrimental to relationship maintenance. However, past work has relied on correlational studies and additional findings from nonhuman animal models suggest that acute changes rather than baseline concentrations in testosterone may in fact protect extant pair-bonds. The present research sought to test the causal role of testosterone in both mate-seeking [single men] and relationship maintenance [paired men] behaviors and perception using a between subject, double blind, placebo treatment protocol. The study recruited 212 healthy men, roughly half of whom were in a committed relationship and half single. The participants were briefly exposed to an attractive female confederate during which time the participants’ verbal and non-verbal behavior was recorded. Results indicated that among single men, testosterone moderated the effects of several of the confederate’s proceptivity behaviors on men’s self-presentation, such that her affiliative behavior was positively correlated with the men’s self-presentation. These results were restricted to single men; testosterone did not alter men’s courtship behavior among paired men, suggesting that acute changes in testosterone may not serve as a relationship protection mechanism in men. Additionally, testosterone caused men, regardless of relationship status, to perceive the confederate’s self-presentation behavior as indicative of her sexual interest. The results provide the first causal evidence for testosterone as a mate-seeking mechanism in healthy adult men and provide an outline to the psychological pathways through which testosterone alters men’s mating psychologies

Acoustic Cues Of Physical Formidability In Cage Fighters

Across the animal kingdom, the sex that experiences the most reproductive variance tends to evolve sexually dimorphic traits—both behavioral and morphological—which aid in reproduction. Human evolution has been marked by greater male intrasexual selection and as a result, men display a variety of secondary sexual characteristics, putatively serving to enhance biological fitness. Among these, fundamental frequency, closely related to perception of pitch, among men is half that of women. Likewise, monotonicity, that is, variance in pitch across an utterance, is higher in men (i.e., women show greater variance in pitch) while formant dispersion, which gives the voice its timbre, is lower. The honesty of these vocal parameters as signaling mechanisms used in context of intrasexual competition has been investigated by a host of researchers; however no research to date has directly assessed the degree to which these parameters predict actual physical formidability, a key step in establishing the honesty of a signal. Here, I address this gap by testing whether these parameters are associated with fighting ability in a large sample of mixed martial arts fighters. Pitch, monotonicity, and timbre were extracted from interviews taken from 292 UFC® fighters and compared with the fighters’ records. Pitch and monotonicity were associated with formidability such that a more masculine profile was associated with higher formidability; timbre however was not associated with formidability. Taken together, these results indicate that pitch and monotonicity may be honest signals of physical formidability

Small farmers in the Romanian dairy market: Do they have a future?

This paper investigates various modes of vertical coordination, with the focus on small farm integration in the Romanian dairy chain. It draws on results from a World Bank study based on semi-structured interviews conducted in spring 2009. The findings indicate that large and prosperous dairy chains fortify their chain efficiency by partner selection and provision of sophisticated assistance to relatively larger farmers. On the contrary, many barriers exist for small and medium-sized dairy chains (processors and farmers). The main factors hampering their potential exploitation are restricted access to inputs markets (capital, know-how) as well as poor quality of input service (agricultural service delivery, veterinary issues). The majority of cow's milk in Romania is still delivered by small farmers who have difficulties fulfilling the requirements of the modern procurement systems. However, small farmers are a relatively heterogeneous group. Hence, different development paths can be expected. In addition to working with retail chains via strengthening horizontal integration, another opportunity for small dairy farmers is to occupy a market niche. Nevertheless, some small farmers will have to leave the dairy market.vertical coordination, small farms, Romania, dairy., Livestock Production/Industries,

A Simplified Model for the Battery Ageing Potential Under Highly Rippled Load for Battery Management and Active Degradation Control

Whereas in typical standardized tests batteries are almost exclusively loaded with constant current or relatively slowly changing cycles, real applications involve rapid load ripple, which do not contribute to the net energy. The trend to reduced filter capacitors and even dynamically reconfigurable batteries further increases the ripple. The influence of rippled load on lithium batteries is therefore receiving increased attention. According to recent studies, accelerated ageing strongly depends on the frequency of the ripple. We use electrochemical models to derive a highly simplified regression model that catches the asymptotic behavior and allows parameter identification and calibration to specific cells. The model allows quantitative monitoring of the additional ageing due to ripple current in battery management systems. Furthermore it enables active control of the ageing potential by influencing the frequency content in modern battery systems, such as reconfigurable batteries.Comment: 7 page

Pay One, Get Hundreds for Free: Reducing Cloud Costs through Shared Query Execution

Cloud-based data analysis is nowadays common practice because of the lower system management overhead as well as the pay-as-you-go pricing model. The pricing model, however, is not always suitable for query processing as heavy use results in high costs. For example, in query-as-a-service systems, where users are charged per processed byte, collections of queries accessing the same data frequently can become expensive. The problem is compounded by the limited options for the user to optimize query execution when using declarative interfaces such as SQL. In this paper, we show how, without modifying existing systems and without the involvement of the cloud provider, it is possible to significantly reduce the overhead, and hence the cost, of query-as-a-service systems. Our approach is based on query rewriting so that multiple concurrent queries are combined into a single query. Our experiments show the aggregated amount of work done by the shared execution is smaller than in a query-at-a-time approach. Since queries are charged per byte processed, the cost of executing a group of queries is often the same as executing a single one of them. As an example, we demonstrate how the shared execution of the TPC-H benchmark is up to 100x and 16x cheaper in Amazon Athena and Google BigQuery than using a query-at-a-time approach while achieving a higher throughput

Double-containment coil with enhanced winding mounting for transcranial magnetic stimulation with reduced acoustic noise

Objective: This work aims to reduce the acoustic noise level of transcranial magnetic stimulation (TMS) coils. TMS requires high currents (several thousand amperes) to be pulsed through the coil, which generates a loud acoustic impulse whose peak sound pressure level (SPL) can exceed 130 dB(Z). This sound poses a risk to hearing and elicits unwanted neural activation of auditory brain circuits. Methods: We propose a new double-containment coil with enhanced winding mounting (DCC), which utilizes acoustic impedance mismatch to contain and dissipate the impulsive sound within an air-tight outer casing. The coil winding is potted in a rigid block, which is mounted to the outer casing by its acoustic nodes that are subject to minimum vibration during the pulse. The rest of the winding block is isolated from the casing by an air gap, and sound is absorbed by foam within the casing. The casing thickness under the winding center is minimized to maximize the coil electric field output. Results: Compared to commercial figure-of-eight TMS coils, the DCC prototype has 10-33 dB(Z) lower SPL at matched stimulation strength, whilst providing 22% higher maximum stimulation strength than equally focal commercial coils. Conclusion: The DCC design greatly reduces the acoustic noise of TMS while increasing the achievable stimulation strength. Significance: The acoustic noise reduction from our coil design is comparable to that provided by typical hearing protection devices. This coil design approach can enhance hearing safety and reduce auditory co-activations in the brain and other detrimental effects of TMS sound.Comment: 8 pages, 5 figure

Ageing Mitigation and Loss Control Through Ripple Management in Dynamically Reconfigurable Batteries

Dynamically reconfigurable batteries merge battery management with output formation in ac and dc batteries, increasing the available charge, power, and life time. However, the combined ripple generated by the load and the internal reconfiguration can degrade the battery. This paper introduces that the frequency range of the ripple matters for degradation and loss. It presents a novel control method that reduces the low-frequency ripple of dynamically reconfigurable battery technology to reduce cell ageing and loss. It furthermore shifts the residual ripple to higher frequencies where the lower impedance reduces heating and the dielectric capacitance of electrodes and electrolyte shunt the current around the electrochemical reactions.Comment: 8 pages, 8 figure