The Blackhole-Dark Matter Halo Connection

We explore the connection between the central supermassive blackholes (SMBH) in galaxies and the dark matter halo through the relation between the masses of the SMBHs and the maximum circular velocities of the host galaxies, as well as the relationship between stellar velocity dispersion of the spheroidal component and the circular velocity. Our assumption here is that the circular velocity is a proxy for the mass of the dark matter halo. We rely on a heterogeneous sample containing galaxies of all types. The only requirement is that the galaxy has a direct measurement of the mass of its SMBH and a direct measurement of its circular velocity and its velocity dispersion. Previous studies have analyzed the connection between the SMBH and dark matter halo through the relationship between the circular velocity and the bulge velocity dispersion, with the assumption that the bulge velocity dispersion stands in for the mass of the SMBH, via the well{}-established SMBH mass{}-bulge velocity dispersion relation. Using intermediate relations may be misleading when one is studying them to decipher the active ingredients of galaxy formation and evolution. We believe that our approach will provide a more direct probe of the SMBH and the dark matter halo connection. We find that the correlation between the mass of supermassive blackholes and the circular velocities of the host galaxies is extremely weak, leading us to state the dark matter halo may not play a major role in regulating the blackhole growth in the present Universe.Comment: Accepted for publication in the Ap

Assessing Empathy Across the Lifespan: A Functional Near Infrared Spectroscopy Approach

This thesis project aimed to utilize functional near infrared spectroscopy (fNIRS) technology in order to assess empathy in a lifespan sample. fNIRS is a non-invasive brain imaging technique that uses properties of light to infer brain activity. Participants ranged in age from 19-75 and were recruited to participate in an fNIRS experiment to assess empathy. Each participant was asked to assume the mental perspective of players on a computer game, and witnessed the player win, lose or tie the game involving a monetary reward. After the fNIRS recording, participants completed personality trait questionnaires related to empathy and emotional contagion. Results revealed brain activity during the win condition was positively correlated with trait perspective taking, and brain activity during the lose condition was positively correlated with emotional contagion. Additionally, younger adults had greater activation in both medial pre-frontal and dorsolateral regions compared to older adults in the win condition. These results suggest older and younger adults process information related to empathy differently in the frontal cortex, and that trait personality characteristics may be related to task-based brain activity in empathy-inducing situations. Understanding the way information processing changes in aging is an important aspect of taking care of the growing aging population

Brain Networks Related to Loneliness in Adolescents

Higher levels of perceived loneliness are associated with poorer health, diseases, and a greater risk of mortality. Studies of loneliness suggest that it is heritable, and that some individuals are more prone to experiencing loneliness than others. Previous neuroimaging studies in adolescents have demonstrated that brain regions involved in emotion processing and regulation, such as the anterior cingulate cortex (ACC), medial prefrontal cortex, and amygdala, are associated with social exclusion and social network size. However, the brain networks underlying loneliness in adolescents are unknown. We used resting state functional connectivity (rs-FC) to investigate brain networks related to loneliness in adolescents. The current project (N=56) focuses on investigating brain networks in adolescents associated with loneliness, as measured by a self-report questionnaire from the NIH Toolbox (Emotion Battery). In addition, measures assessing perceived rejection and friendship were included to investigate associations with loneliness. Participants underwent resting state functional magnetic resonance imaging to obtain a measure of functional connectivity. We found that loneliness was positively correlated with perceived rejection (r=.8,

Effects of Gender on Empathy and Prosocial Behavior

Empathy plays an important role in our aging society, especially when it comes to emotional well-being and relationships with others. There is some evidence that as adults age, they show a decrease in the cognitive domain of empathy (the ability to understand others’ thoughts and feelings) and an increase in the emotional domain of empathy (feelings of compassion and sympathy towards others). Previous studies have also revealed that women self-report higher emotional and cognitive empathy than men. Based on Daniel Batson’s empathy altruism hypothesis, more empathetic individuals are also more likely to engage in prosocial behaviors towards others. However, the impact of gender on prosocial behavior towards others in need has not been investigated in older adults. The current study aims to identify differences in empathy using the Interpersonal Reactivity Index questionnaire (IRI), gender role by using the Bem Sex Role Inventory 12 item questionnaire (BSRI-12), and prosocial behavior by playing the dictator game. Data has been collected and analyzed from 22 healthy older (55-90 years) and younger (19-35 years) participants from the greater Omaha area. Preliminary results reveal that older adults self-report higher levels of emotional empathy and lower levels of one domain of cognitive empathy relative to younger adults. Preliminary evidence suggests there is a trend towards individuals who self-report feminine traits also report higher cognitive and emotional empathy than individuals who identify with masculine traits. Future research in our lab will clarify the strength of these relationships as a function of age and gender

As the world ages

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Annual cycle of the microzooplankton communities in the waters surrounding the Palm Island Nature Reserve (north Lebanon), with special attention to tintinnids

The distribution, abundance and annual cycle of microzooplankton communities have been studied monthly at five sampling stations in the north Lebanon, covering both neritic and oceanic waters in the vicinity of small islands situated 5 km offshore.In general, the density of microprotozoans, except for ciliates, increased from the coastal towards the offshore area, with stations situated near the islands being similar to the offshore rather than to the coastal ones. The microprotozoan species showed their highest numbers in late autumn and early winter. Foraminifera abundance ranged from 20 to 3390 inds.m -3 (mean= 549) whereas Acantharia abundance was highest in spring and ranged from 0 to 2608 inds.m -3 (mean 259). The Polycistina had their highest numbers in late winter, which ranged from 0 to 6024 inds.m -3 (mean= 740). The Heliozoa were abundant in late autumn with numbers ranging from 0 to 5165 inds.m -3 (mean= 555). The annual cycle of Tintinnids at all the stations was bimodal with a principal peak in October-November and another one in May, while minimum numbers were recorded in August-September. A succession of populations was observed all year round with a density ranging between 344 and 38986 inds.m -3 (mean = 10878). Ninety different species of Tintinnids were recorded. The diversity index varied between 0.19 and 4.15. It was concluded that there was a large-scale gradient in seasonal diversity which could be related to the annual average sea surface temperature and to the development of the vertical thermic structure