摘要 :
We study the phantom fluid in the late universe, thus assuming the equation of state parameter w to be less than -1. The fluid is assumed to consist of two components, one laminar component rho and one turbulent component rho T, t...
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We study the phantom fluid in the late universe, thus assuming the equation of state parameter w to be less than -1. The fluid is assumed to consist of two components, one laminar component rho and one turbulent component rho T, the latter set proportional to rho as well as to the Hubble parameter, rho T = 3 tau H rho with tau a positive constant associated with the turbulence. The effective energy density is taken to be rho e = rho + rho T, and the corresponding effective pressure is rho e = w rho e , with w constant. These basic assumptions lead to a Big Rip universe; the physical quantities diverging during a finite rip time t(s). We then consider the mass accretion of a black hole in such a universe. The most natural assumption of setting the rate dM/dt proportional to M-2 times the sum rho e + rho e leads to a negative mass accretion, where M(t) goes to zero linearly in (t(s)- t) near the singularity. The Hubble parameter diverges as (t(s)- t)(-1), whereas rho e and rho e diverge as (t(s)- t)(-2). We also discuss other options and include, for the sake of comparison, some essential properties of mass accretion in the early (inflationary) universe.
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Some new identities are established for universal Osborn loops and left(right) universal Osborn loops. These identities axe true for Moufang loops, extra loops, CC-loops, VD-loops and universal WIPLs. CC-loops. VD-loops and univer...
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Some new identities are established for universal Osborn loops and left(right) universal Osborn loops. These identities axe true for Moufang loops, extra loops, CC-loops, VD-loops and universal WIPLs. CC-loops. VD-loops and universal WIPLs are observed to have a weaker inverse property(x~ρ = x~λx~λ · x) and a double left inverse property((x~λ · xy)x~λ · x = y).
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Universality, where microscopic details become irrelevant, takes place in thermodynamic phase transitions. The universality is captured by a singular scaling function of the thermodynamic variables, where the scaling exponents are...
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Universality, where microscopic details become irrelevant, takes place in thermodynamic phase transitions. The universality is captured by a singular scaling function of the thermodynamic variables, where the scaling exponents are determined by symmetries and dimensionality only. Universality can persist even for nonequilibrium phase transitions. It implies that a hydrodynamic approach can capture the singular universal scaling function, even far from equilibrium. In particular, we show these results for phase transitions in the large deviation function of the current in diffusive systems with particle-hole symmetry. For such systems, we find the scaling exponents of the universal function and show they are independent of microscopic details as well as boundary conditions.
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We give a necessary and sufficient condition so that we have disjoint universality for sequences of operators that map a holomorphic function to a partial sum of its Taylor expansion. This problem is connected with doubly universa...
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We give a necessary and sufficient condition so that we have disjoint universality for sequences of operators that map a holomorphic function to a partial sum of its Taylor expansion. This problem is connected with doubly universal Taylor series and this is an effort to generalize the concept to multiply universal Taylor series. (C) 2016 Elsevier Inc. All rights reserved.
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摘要 :
For a simply connected domain G, we study the problem of disjoint universality for the sequences of operators T-alpha,T-n : H(G) -> H(G), defined by T-alpha,T-n(f)(z) = Sigma(n)(j=0) f((j))(z)/j(!) (alpha z)(j), where alpha is an ...
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For a simply connected domain G, we study the problem of disjoint universality for the sequences of operators T-alpha,T-n : H(G) -> H(G), defined by T-alpha,T-n(f)(z) = Sigma(n)(j=0) f((j))(z)/j(!) (alpha z)(j), where alpha is an element of C -{0}. Note that T-alpha,T-n(f)(z) is the nth partial sum j=0 of the Taylor expansion of f around z on (alpha + 1)z. The motivation to study such sequences comes from universal Taylor series, by changing the role of the center of expansion. (c) 2021 Elsevier Inc. All rights reserved.
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The most massive stars in the universe are also the most fascinating. Exceedingly rare,theynevertheless play an important role in galactic ecology and in the chemical evolution of thecosmos.They are born in gigantic molecular clou...
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The most massive stars in the universe are also the most fascinating. Exceedingly rare,theynevertheless play an important role in galactic ecology and in the chemical evolution of thecosmos.They are born in gigantic molecular clouds and they light up with an enormous out-pouring of ultraviolet radiation.Pressure exerted by these forms of light on heavy elementspresent in the stellar atmosphere results in a very powerful wind which enriches the regionsbetween the stars and injects large amounts of energy in their surroundings.The life of mas-sive stars is brief-a hundredth of that of ordinary,sun-like stars-and ends in a giganticexplosion detectable to distances of billions of light-years.With the help of beautiful imagesobtained by the largest ground-based and space telescopes,I will describe the life and deathof these stars which illuminate our universe.
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摘要 :
Aim Carbon mono-
xide (CO) poisoning is a common
cause of population morbidity
and mortality in Croatia and
worldwide. Here we offer our ex-
perience. Methods During the
period 2000–2006, 20 patients
were admitted to the hospital...
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Aim Carbon mono-
xide (CO) poisoning is a common
cause of population morbidity
and mortality in Croatia and
worldwide. Here we offer our ex-
perience. Methods During the
period 2000–2006, 20 patients
were admitted to the hospital for
suspected CO poisoning; conse-
quently carboxyhemoglobin
(COHb) levels were measured.
According to clinical manifesta-
tions, patients were described as
having a mild, moderate, or se-
vere intoxication level. Complica-
tions, treatment and outcome
were analyzed. Results All intoxi-
cations were accidental; 18 of
them occurred in winter months.
Most represented were females
(14 cases), age groups 20–30 and
older than 60 yrs. Moderate levels
(9 patients) having a COHb medi-
an of 18.5% (30–38) and mild
levels (8 patients) with a COHbmedian of 24.6% (19.5–31) domi-
nated. The most common symp-
toms and complications were the
central nervous (20 cases),
cardiovascular (8 cases), respira-
tory (7 cases) and gastrointestinal
systems (7 cases). Only one fe-
male patient developed MOF syn-
drome. All patients were given
100% oxygen, 2 were mechani-
cally ventilated, and 2 underwenthyperbaric oxygen therapy.
Length of ICU treatment was
2.3 days for mild, 3.1 days for
moderate, and 12.7 days for se-
vere poisoning (p=0.05). Only
one patient died, the others were
discharged in good condition.
Conclusion CO poisoning, if de-
tected early and the patient is
supplied with oxygen, has good
prognosis. Nonetheless, preven-tion is even more important, con
sidering the high prevalence of
accidental intoxications.
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摘要 :
All the galaxy clusters in thevisible Universe are beingpulled in a common directionby an unseen mass far, far beyond thehorizon of our visible Universe.
摘要 :
The Triple Helix model highlights the third mission' of universities to engage in IP (intellectual property) creation and technology transfer activities further downstream. This paper uses publications data and US patent data to e...
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The Triple Helix model highlights the third mission' of universities to engage in IP (intellectual property) creation and technology transfer activities further downstream. This paper uses publications data and US patent data to examine the role played by leading research-intensive universities in the national innovation systems of the emerging economy of China and the newly industrialised economies (NIE) of Singapore, Hong Kong, Korea and Taiwan. Our analysis highlights significant differences amongst these five East Asian economies, and also reveals contrasts to observed patterns in the USA and Europe. Our findings confirm that universities in the five economies have increased their contribution to their respective national innovation systems in terms of research output and R&D collaboration. The NIE universities experienced rapid patent growth rates over 1995-2005, followed by Chinese universities in the subsequent period of 2006-2010. However, the contribution of universities in all five East Asian economies to the total volume of IP creation in their economies generally remains low. Moreover, patent quality is low compared to patents from non-university sectors, suggesting weak technology commercialisation impacts.
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Previous research has claimed that universities can enhance the effectiveness of knowledge transfer activities by establishing a clear strategic goal and aligning all their activities towards that direction. To shed new light on t...
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Previous research has claimed that universities can enhance the effectiveness of knowledge transfer activities by establishing a clear strategic goal and aligning all their activities towards that direction. To shed new light on this issue, in this paper we explore the determinants of universities' strategic choices in the field of knowledge transfer (KT). We identify theoretically and empirically three university KT strategies: income-generation strategy, service-to-faculty strategy, and local development strategy. We then investigate the role of university-level factors that determine the strategic choice of universities, particularly focusing on university horizontal (generalist vs. specialist) and vertical (high vs. low prestige) diversity. The empirical analysis relies on a unique survey of 178 university TTO managers across European universities, combined with additional data sources. Our results show that generalist and low prestige universities mainly pursue the local development strategy, while specialist and high prestige ones are more oriented towards the income generation strategy. These findings are highly relevant for theory and practice of KT in academic insitutions, given the relevance that the university third mission has for economic and societal development.
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