11,226 research outputs found
The colour of the narrow line Sy1-blazar 0324+3410
Aims. We investigate the properties of the host galaxy of the blazar
J0324+3410 (B2 0321+33) by the analysis of B and R images obtained with the NOT
under good photometric conditions. Methods: The galaxy was studied using
different methods: Sersic model fitting, unsharp-masked images, B-R image and
B-R profile analysis. Results: The images show that the host galaxy has a
ring-like morphology. The B-R colour image reveals two bluish zones: one that
coincides with the nuclear region, interpreted as the signature of emission
related to the active nucleus, the other zone is extended and is located in the
host ring-structure. We discuss the hypothesis that the later is thermal
emission from a burst of star formation triggered by an interacting/merging
process
Search for EC and ECEC processes in Sn
Limits on EC (here EC denotes electron capture) and ECEC processes
in Sn have been obtained using a 380 cm HPGe detector and an
external source consisting of 53.355 g enriched tin (94.32% of Sn). A
limit with 90% C.L. on the Sn half-life of y for
the ECEC(0) transition to the excited state in Cd (1871.0
keV) has been established. This transition is discussed in the context of a
possible enhancement of the decay rate by several orders of magnitude given
that the ECEC process is nearly degenerate with an excited state in the
daughter nuclide. Prospects for investigating such a process in future
experiments are discussed. The limits on other EC and ECEC processes
in Sn were obtained on the level of y at the
90% C.L.Comment: 14 pages, 4 figure
Permeability and Protest in Lane 49: Entangling Materialities of Place with Housing Activism in Shanghai
Since China’s implementation of a neo-liberal housing regime, housing activism has boomed. Whilst activism is ultimately in place, as increasingly recognised within protest work, there is limited reflection upon how permeable material histories are entangled with the throwntogetherness of place as a site for protest. Employing ethnography over three months, this article follows the emergence, organisation and implementation of housing activism in Lane 49, a public housing community in downtown Shanghai. Utilising feminist geography and feminist political theorisations of material permeability this article contributes to Chinese geographies of protest, providing a local epistemology of housing activism which demonstrates the importance of drawing materiality into understandings of activist tactics. The article also contributes to radical geographies of protest by deconstructing the idea of public protest in a public place and thus offering opportunities to demonstrate how, through blurring public-private binaries, protest can emerge and survive in authoritative governance regimes
Everyday domestic water and energy consumption in Shanghai homes: The resurgence and persistence of gendered practices in China
China's ecological civilization centralises households as a unit of intervention for environmental policy. The household constructed within such policy reduces complex social arrangements and processes and results in efficiency and behaviour change interventions. Such interventions have had limited success and contribute to reproducing inequality. This paper uses ethnographic methods to develop insights into everyday practices that consume energy and water within homes in urban China. In doing so, understandings of both the responsibilities and temporalities of labour for these practices are developed, and the entanglement of these practices across diverse policy arenas is explored. Focusing upon water treatment, cooking, dishwashing, and laundering - this paper demonstrates not only how women have a much greater responsibility for such practices, but that the importance of women's labour is considered greater for practices in which hygiene is considered critical and contributing to health protection. Gendered labour is connected to the resurgence of Confucian gender ideologies within CCP policy and discourse post-1968. The exacerbation of anxieties around the health of children is further connected with parents experiencing pressure in raising their children as ‘high-quality citizens’
The Co-occurrence of child and intimate partner maltreatment in the family: characteristics of the violent perpetrators
This study considers the characteristics associated with mothers and fathers who maltreat their child and each other in comparison to parents who only maltreat their child. One hundred and sixty-two parents who had allegations of child maltreatment made against them were considered. The sample consisted of 43 fathers (Paternal Family—PF) and 23 mothers (Maternal Family—MF) who perpetrated both partner and child maltreatment, together with 23 fathers (Paternal Child—PC) and 26 mothers (Maternal Child—MC) who perpetrated child maltreatment only. In addition, 2 fathers (Paternal Victim—PV) and 23 mothers (Maternal Victim—MV) were victims of intimate partner maltreatment and perpetrators of child maltreatment and 7 fathers (Paternal Non-abusive Carer—PNC) and 15 mothers (Maternal Non-abusive Carer—MNC) did not maltreat the child but lived with an individual who did. Within their family unit, 40.7% of parents perpetrated both intimate partner and child maltreatment. However, fathers were significantly more likely to maltreat both their partner and child than mothers and mothers were significantly more likely to be victims of intimate partner violence than fathers. PF fathers conducted the highest amount of physical and/or sexual child maltreatment while MC and MV mothers perpetrated the highest amount of child neglect. Few significant differences between mothers were found. PF fathers had significantly more factors associated with development of a criminogenic lifestyle than PC fathers. Marked sex differences were demonstrated with PF fathers demonstrating significantly more antisocial characteristics, less mental health problems and fewer feelings of isolation than MF mothers. MC mothers had significantly more childhood abuse, mental health problems, parenting risk factors and were significantly more likely to be biologically related to the child than PC fathers. This study suggests that violent families should be assessed and treated in a holistic manner, considering the effects of partner violence upon all family members, rather than exclusively intervening with the violent man
Fast linear-space computations of longest common subsequences
AbstractSpace saving techniques in computations of a longest common subsequence (LCS) of two strings are crucial in many applications, notably, in molecular sequence comparisons. For about ten years, however, the only linear-space LCS algorithm known required time quadratic in the length of the input, for all inputs. This paper reviews linear-space LCS computations in connection with two classical paradigms originally designed to take less than quadratic time in favorable circumstances. The objective is to achieve the space reduction without alteration of the asymptotic time complexity of the original algorithm. The first one of the resulting constructions takes time O(n(m−l)), and is thus suitable for cases where the LCS is expected to be close to the shortest input string. The second takes time O(ml log(min[s, m, 2nl])) and suits cases where one of the inputs is much shorter than the other. Here m and n (m⩽n) are the lengths of the two input strings, l is the length of the longest common subsequences and s is the size of the alphabet. Along the way, a very simple O(m(m−l)) time algorithm is also derived for the case of strings of equal length
Harnessing elastic instabilities for enhanced mixing and reaction kinetics in porous media
Turbulent flows have been used for millennia to mix solutes; a familiar
example is stirring cream into coffee. However, many energy, environmental, and
industrial processes rely on the mixing of solutes in porous media where
confinement suppresses inertial turbulence. As a result, mixing is drastically
hindered, requiring fluid to permeate long distances for appreciable mixing and
introducing additional steps to drive mixing that can be expensive and
environmentally harmful. Here, we demonstrate that this limitation can be
overcome just by adding dilute amounts of flexible polymers to the fluid.
Flow-driven stretching of the polymers generates an elastic instability (EI),
driving turbulent-like chaotic flow fluctuations, despite the pore-scale
confinement that prohibits typical inertial turbulence. Using in situ imaging,
we show that these fluctuations stretch and fold the fluid within the pores
along thin layers (``lamellae'') characterized by sharp solute concentration
gradients, driving mixing by diffusion in the pores. This process results in a
reduction in the required mixing length, a increase in
solute transverse dispersivity, and can be harnessed to increase the rate at
which chemical compounds react by -- enhancements that we rationalize
using turbulence-inspired modeling of the underlying transport processes. Our
work thereby establishes a simple, robust, versatile, and predictive new way to
mix solutes in porous media, with potential applications ranging from
large-scale chemical production to environmental remediation
Elastic turbulence generates anomalous flow resistance in porous media
Diverse processes rely on the viscous flow of polymer solutions through
porous media. In many cases, the macroscopic flow resistance abruptly increases
above a threshold flow rate in a porous medium---but not in bulk solution. The
reason why has been a puzzle for over half a century. Here, by directly
visualizing the flow in a transparent 3D porous medium, we demonstrate that
this anomalous increase is due to the onset of an elastic instability. We
establish that the energy dissipated by the unstable flow fluctuations, which
vary across pores, generates the anomalous increase in flow resistance through
the entire medium. Thus, by linking the pore-scale onset of unstable flow to
macroscopic transport, our work provides generally-applicable guidelines for
predicting and controlling polymer solution flows
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