29 research outputs found
Cardiovascular emotional dampening and blood pressure: Is there a relationship between diastolic blood pressure and risk-taking behavior?
Persons with higher blood pressure have emotional dampening, a reduced response to emotionally meaningful stimuli. Dampening of perceived threat could influence risk-related decision-making. The present study examined the relationship between cardiovascular emotional dampening and risk behavior. We measured resting diastolic blood pressure (DBP), emotion recognition, and risk-taking behavior in 44 healthy, self-identified males and 44 females with an average age of 22.5 years. Participants judged the type of emotion depicted in faces and sentences as an index of emotion recognition. We measured risk with a modified Youth Risk Behavior Survey. Results showed a significant correlation between risk-taking behaviors and resting DBP [r(88) = .408, p \u3c.001.]. Sex was also correlated with resting DBP, [r(88) = -.230, p = .031]; however, a multiple regression showed no main effects or interactions with sex in prediction of risk. These results indicate that young adults with higher DBP report more risk-taking behavior and show less accuracy in recognition of emotion in faces, suggesting that cardiovascular emotional dampening may reduce threat appraisal and increase high-risk behavior. The effect of blood pressure on risk behavior could contribute to increased disease risk later in life
On definitions of "mathematician"
The definition of who is or what makes a ``mathematician" is an important and
urgent issue to be addressed in the mathematics community. Too often, a
narrower definition of who is considered a mathematician (and what is
considered mathematics) is used to exclude people from the discipline -- both
explicitly and implicitly. However, using a narrow definition of a
mathematician allows us to examine and challenge systemic barriers that exist
in certain spaces of the community. This paper explores and illuminates
tensions between narrow and broad definitions and how they can be used to
promote both inclusion and exclusion simultaneously. In this article, we
present a framework of definitions based on identity, function, and
qualification and exploring several different meanings of ``mathematician". By
interrogating various definitions, we highlight their risks and opportunities,
with an emphasis on implications for broadening and/or narrowing participation
of underrepresented groups.Comment: 21 pages, 2 figure
Design of a Ruthenium-Cytochrome c Derivative to Measure Electron Transfer to the Initial Acceptor in Cytochrome c Oxidase
A ruthenium-labeled cytochrome c derivative was prepared to meet two design criteria: the ruthenium group must transfer an electron rapidly to the heme group, but not alter the interaction with cytochrome c oxidase. Site-directed mutagenesis was used to replace His39 on the backside of yeast C102T iso-1-cytochrome c with a cysteine residue, and the single sulfhydryl group was labeled with (4-bromomethyl-4' methylbipyridine) (bis-bipyridine)ruthenium(II) to form Ru-39-cytochrome c (cyt c). There is an efficient pathway for electron transfer from the ruthenium group to the heme group of Ru-39-cyt c comprising 13 covalent bonds and one hydrogen bond. Electron transfer from the excited state Ru(II*) to ferric heme c occurred with a rate constant of (6.0 +/- 2.0) x 10(5) s-1, followed by electron transfer from ferrous heme c to Ru(III) with a rate constant of (1.0 +/- 0.2) x 10(6) s-1. Laser excitation of a complex between Ru-39-cyt c and beef cytochrome c oxidase in low ionic strength buffer (5 mM phosphate, pH7) resulted in electron transfer from photoreduced heme c to CuA with a rate constant of (6 +/- 2) x 10(4) s-1, followed by electron transfer from CuA to heme a with a rate constant of (1.8 +/- 0.3) x 10(4) s-1. Increasing the ionic strength to 100 mM leads to bimolecular kinetics as the complex is dissociated. The second-order rate constant is (2.5 +/- 0.4) x 10(7) M-1s-1 at 230 mM ionic strength, nearly the same as that of wild-type iso-1-cytochrome c
Risk Factors Associated with Cognitive Decline after Cardiac Surgery: A Systematic Review
Modern day cardiac surgery evolved upon the advent of cardiopulmonary bypass machines (CPB) in the 1950s. Following this development, cardiac surgery in recent years has improved significantly. Despite such advances and the introduction of new technologies, neurological sequelae after cardiac surgery still exist. Ischaemic stroke, delirium, and cognitive impairment cause significant morbidity and mortality and unfortunately remain common complications. Postoperative cognitive decline (POCD) is believed to be associated with the presence of new ischaemic lesions originating from emboli entering the cerebral circulation during surgery. Cardiopulmonary bypass was thought to be the reason of POCD, but randomised controlled trials comparing with off-pump surgery show contradictory results. Attention has now turned to the growing evidence that perioperative risk factors, as well as patient-related risk factors, play an important role in early and late POCD. Clearly, identifying the mechanism of POCD is challenging. The purpose of this systematic review is to discuss the literature that has investigated patient and perioperative risk factors to better understand the magnitude of the risk factors associated with POCD after cardiac surgery