17 research outputs found
Bulk viscosity of Mixed nucleon-hyperon-quark Matter in Neutron stars
We calculate the coefficient of bulk viscosity by considering the
non-leptonic weak interactions in the cores of hybrid stars with both hyperons
and quarks. We first determine the dependence of the production rate of
neutrons on the reaction rate of quarks in the non-leptonic processes, that is
. The
conversion rate, in our scenario is a complicated function of baryon
number density. We also consider medium effect of quark matter on bulk
viscosity. Using these results, we estimate the limiting rotation of the hybrid
stars, which may suppress the r-mode instability more effectively. Hybrid stars
should be the candidates for the extremely rapid rotators .Comment: This paper contains 17 pages,8 figures and 1 table and is accepted by
Monthly Notices of the Royal Astronomical Societ
Recent glitches detected in the Crab pulsar
From 2000 to 2010, monitoring of radio emission from the Crab pulsar at
Xinjiang Observatory detected a total of nine glitches. The occurrence of
glitches appears to be a random process as described by previous researches. A
persistent change in pulse frequency and pulse frequency derivative after each
glitch was found. There is no obvious correlation between glitch sizes and the
time since last glitch. For these glitches and
span two orders of magnitude. The pulsar suffered the
largest frequency jump ever seen on MJD 53067.1. The size of the glitch is
6.8 Hz, 3.5 times that of the glitch occured in
1989 glitch, with a very large permanent changes in frequency and pulse
frequency derivative and followed by a decay with time constant 21 days.
The braking index presents significant changes. We attribute this variation to
a varying particle wind strength which may be caused by glitch activities. We
discuss the properties of detected glitches in Crab pulsar and compare them
with glitches in the Vela pulsar.Comment: Accepted for publication in Astrophysics & Space Scienc
Facebook's Mobile Career
At the end of its first decade, Facebook’s identity, popularity, and characteristics are shaped in important ways by its becoming a form of mobile media, as much as it as platform associated with Internet and social media. This paper seeks to explore and understand Facebook as the important force in mobile media and communication it now is. It draws upon and combines perspectives from technology production, design, and economy, as well as user adoption, consumption, practices, affect, emotion, and resistance. The paper discusses the beginnings of mobile Facebook, and the early adoption of mobile Facebook associated with the rise of smartphones. The second part of the paper explores Facebook’s integration with photography (with Instagram) and social games (such as Zynga’s Farmville). The paper argues that Facebook’s mobile career is an accomplishment that has distinctively melded evolving affordances, everyday use across a wide range of settings, as well as political economies, corporate strategy, and design.Australian Research Counci
Verification of Arabidopsis stock collections using SNPmatch, a tool for genotyping high-plexed samples
The Big Meaning of Small Messages : The Use of WhatsApp in Intergenerational Family Communication
This study explores the use of WhatsApp instant messenger in extended families in two countries, Finland and Italy, that represent different family and communication cultures. Qualitative research material was collected in 2014/2015 from families consisting of three or more generations and living either in the same or different households. A directed approach to qualitative content analysis was applied in the analysis of the research data. The results of the study show that WhatsApp is considered to facilitate family interaction across generations. The success of WhatsApp in the family context accounts for two main factors: first, for the possibility to reach the whole family at once; and secondly, for its capacity to promote “phatic communion” via small messages. While utilizing various communicative modalities of WhatsApp (text and voice messages, photos, videos), family members take into account others’ preferences and communication skills.peerReviewe