13,502 research outputs found
Comment on "Non-Mean-Field Behavior of the Contact Process on Scale-Free Networks"
Recently, Castellano and Pastor-Satorras [1] utilized the finite size scaling
(FSS) theory to analyze simulation data for the contact process (CP) on
scale-free networks (SFNs) and claimed that its absorbing critical behavior is
not consistent with the mean-field (MF) prediction. Furthermore, they pointed
out large density fluctuations at highly connected vertices as a possible
origin for non-MF critical behavior. In this Comment, we propose a scaling
theory for relative density fluctuations in the spirit of the MF theory, which
turns out to explain simulation data perfectly well. We also measure the value
of the critical density decay exponent, which agrees well with the MF
prediction. Our results strongly support that the CP on SFNs still exhibits a
MF-type critical behavior.Comment: 1 page, 2 figures, typos are correcte
Structure, organization, and evolution of satellite DNAs in species of the genera Beta and Patellifolia
Genomes of higher plants comprise a large proportion of repetitive DNAs, where one major class is satellite DNA. Satellite DNA is organized in tandem arrays of basic repeating units, which often occurs in heterochromatin of centromeric/pericentromeric and intercalary as well as subtelomeric regions. Besides these typical satellite repeats, there are also non-typical satellite DNAs, which are organized in short tandem arrays and integrated into a transposable element. The chromosomal localization of non-typical satellites is not in large regions of heterochromatin, but tend to be dispersed along chromosomes. This thesis describes the identification of the major repeat classes including major satellite content in six beet and related species. The focus was on identification and characterization of new satellite families in the beet genomes.
In this study, the information regarding repetitive DNA as well as satellite families fraction in six beet and related species was gained based on graph-based clustering of next generation sequenced short sequence reads. The repeat proportion of the six analyzed species ranges from 34.4% in C. quinoa to 65.6% in B. lomatogona, in which the portion of nearly 50% belongs to B. vulgaris, B. nana, P. procumbens, and P. patellaris. Among all classes of repetitive DNAs, LTR retrotransposons are the most abundant repeat type in all analyzed genomes, which is a common feature of higher plant genomes. The other repeat sequences are DNA transposons, rDNA, and satellite DNA with variable portions in different species. A set of satellite families in each species was analyzed in detail and reflects the relationship between six species. The closely related relationship between B. lomatogona and B. nana as well as between P. procumbens and P. patellaris is affirmed by seven and 13 satellite families shared between two species, respectively. Similarly, the closer relationship between B. vulgaris and two species B. lomatogona and B. nana than between B. vulgaris and two species P. procumbens and P. patellaris from the sister-genus Patellifolia is also confirmed. C. quinoa is a distantly related species and this is reflected by vastly different satellite content. Therefore, satellite DNA analysis might be a useful tool to trace species evolution.
In the B. lomatogona genome, by the application of RepeatExplorer tool, six novel tandemly repeated DNA sequences were identified and designated BlSat1-BlSat6. The three typical satellite families BlSat1, BlSat5, and BlSat6 are organized in tandem arrays in large heterochromatic blocks. BlSat1 is mainly localized in the pericentric region of the chromosome 3, 5, 6, and 9, while BlSat5 is amplified in the pericentromeric region of the chromosome 3, 5, and 7. BlSat6 is a chromosome-specific satellite and is located in the subtelomeric region on the south arm of the chromosome 8. The other three satellite families BlSat2, BlSat3, and BlSat4 are characterized as non-typical satellite DNA because of their dispersed distribution along chromosomes. BlSat2 and BlSat3 are identified as a tandem repeat domain in Ogre/Tat retrotransposons. The occurrence of one or several short tandem arrays in a transposable element is a common phenomenon in both animals and plants. These short repeats are considered to be continuously evolving and eventually amplifying to new satellite families.
Furthermore, the distribution of the six new satellite families in beet and related species was confirmed by comparative PCR, comparative Southern hybridization, and mapping of sequence reads from referent species against each satellite sequence. The BlSat1 and BlSat6 satellite families are specific for the genus Beta, while BlSat5 is only amplified in two sections Corollinae and Nanae of the genus Beta. BlSat4 is an ancient satellite family which exists in all tested species belonging to the genera Beta, Patellifolia, Chenopodium, and Spinacia, whereas BlSat2 and BlSat3 might have evolved before the separation of the genus Beta and Patellifolia but their sequences have been lost or heavily diverged during the species radiation.
Comparison of two wild beet genomes P. procumbens and P. patellaris was performed aiming to address the open question whether P. patellaris is auto- or allotetraploid. The high similarity between these two genomes indicates their close relationship. However, the genetic difference between two genomes, in particular the molecular characteristics as well as the chromosomal localization of two satellite families PproSat1 and PpatSat1, might support a hypothesis that P. patellaris is allotetraploid species with a half of its chromosome set derived from P. procumbens.
The results obtained in this work might provide comprehensive information of the repetitive classes as well as satellite families in the genomes of beets and related species. The results can be used as the species-specific and chromosome-specific markers in beet genome studies
The study on factors affecting the participation in the organization of the community tourism by farmer households in Tra Ving province, Vietnam
Abstract. The study on the factors influencing farmer households’ participation in the organization of community-based tourism in Tra Vinh province was conducted by the gathering of primary data from 200 households in three islands of Tan Quy (Cau Ke district), Long Tri (Tra Vinh city), and Hoa Minh (Chau Thanh district) in Tra Vinh province. Through the use of the logistic regression model, the study found that there were six factors affecting the decision to participate in tourism, including the age of farmers, householders, and the educational level of householders, household size, family income, social relations and traditional trades. In particular, traditional trades, household income, and social relationships strongly influence farmers’ participation in organizing community-based tourism activities in Tra Vinh province.Keywords. Community tourism, Households, Island, Logistic regression, Income, Traditional trades.JEL. I13, I20, I30
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Data’s Intimacy: Machinic Sensibility and the Quantified Self
Today, machines observe, record, sense the world – not just for us, but sometimes instead of us (in our stead), and even indifferently to us humans. And yet, we remain human. Correlationism may not be up to a comprehensive ontology, but the ways in which we encounter, and struggle to make some kind of sense of, machinic sensibility matters. The nature of that encounter is not instrumentality, or even McLuhanian extension, but a full-blown ‘relationship’ where the terms by which machines ‘experience’ the world, and communicate with each other, parametrises the conditions for our own experience. This essay will play out one such relationship currently in the making: the boom in self-tracking technologies, and the attendant promise of data’s intimacy.
This essay proceeds in three sections, all of which draw on a larger research project into self-tracking and contemporary data epistemologies. It thus leverages observations from close reading of self-tracking’s publicisation in the mass media between 2007 and 2016; analysis of over fifty self-tracking products, some of it through self-experimentation; and interviews and ethnographic observation, primarily of the ‘Quantified Self’ connoisseur community. The first section examines the dominant public presentations of self-tracking in early twenty-first century discourse. This discourse embraces a vision of automated and intimate self-surveillance, which is then promised to deliver superior control and objective knowledge over the self. Next, I link these promises to the recent theoretical turns towards the agency of objects and the autonomous sensory capacities of new media to consider the implications of such theories – and the technological shifts they address – for the phenomenology of the new media subject. Finally, I return to self-tracking discourse to consider its own idealisation of such a subject – what I call ‘data-sense’. I conclude by calling for a more explicit public and intellectual debate around the relationships we forge with new technologies, and the consequences they have for who – and what – is given which kinds of authority to speak the truth of the ‘self’
Data Epistemologies / Surveillance and Uncertainty
Data Epistemologies studies the changing ways in which ‘knowledge’ is defined, promised, problematised, legitimated vis-á-vis the advent of digital, ‘big’ data surveillance technologies in early twenty-first century America. As part of the period’s fascination with ‘new’ media and ‘big’ data, such technologies intersect ambitious claims to better knowledge with a problematisation of uncertainty. This entanglement, I argue, results in contextual reconfigurations of what ‘counts’ as knowledge and who (or what) is granted authority to produce it – whether it involves proving that indiscriminate domestic surveillance prevents terrorist attacks, to arguing that machinic sensors can know us better than we can ever know ourselves.
The present work focuses on two empirical cases. The first is the ‘Snowden Affair’ (2013-Present): the public controversy unleashed through the leakage of vast quantities of secret material on the electronic surveillance practices of the U.S. government. The second is the ‘Quantified Self’ (2007-Present), a name which describes both an international community of experimenters and the wider industry built up around the use of data-driven surveillance technology for self-tracking every possible aspect of the individual ‘self’. By triangulating media coverage, connoisseur communities, advertising discourse and leaked material, I examine how surveillance technologies were presented for public debate and speculation.
This dissertation is thus a critical diagnosis of the contemporary faith in ‘raw’ data, sensing machines and algorithmic decision-making, and of their public promotion as the next great leap towards objective knowledge. Surveillance is not only a means of totalitarian control or a technology for objective knowledge, but a collective fantasy that seeks to mobilise public support for new epistemic systems. Surveillance, as part of a broader enthusiasm for ‘data-driven’ societies, extends the old modern project whereby the human subject – its habits, its affects, its actions – become the ingredient, the raw material, the object, the target, for the production of truths and judgments about them by things other than themselves
Finite-size scaling in complex networks
A finite-size-scaling (FSS) theory is proposed for various models in complex
networks. In particular, we focus on the FSS exponent, which plays a crucial
role in analyzing numerical data for finite-size systems. Based on the
droplet-excitation (hyperscaling) argument, we conjecture the values of the FSS
exponents for the Ising model, the susceptible-infected-susceptible model, and
the contact process, all of which are confirmed reasonably well in numerical
simulations
cis-DiaquaÂbisÂ(2,2′-bipyrimidine-κ2 N 1,N 1′)manganese(II) bisÂ(perchlorate) nitroÂmethane disolvate monohydrate
The asymmetric unit of the title compound, [Mn(C8H6N4)2(H2O)2](ClO4)2·2CH3NO2·H2O, contains one half of a cationic MnII complex, a ClO4
− anion, a nitroÂmethane solvent molÂecule and one half-molÂecule of water. The complex molÂecule and the solvent water molÂecule are located on a twofold rotation axis. In the complex, the MnII ion has a distorted cis-N4O2 octaÂhedral coordination geometry defined by four N atoms of the two chelating 2,2′-bipyrimidine ligands and two O atoms of water molÂecules. In the crystal, the complex cations, anions and solvent molÂecules are linked by interÂmolecular O—H⋯N, O—H⋯O and weak C—H⋯O hydrogen bonds. The ClO4
− anion is disordered over two sites with a site-occupancy factor of 0.512 (12) for the major component
Removal of inorganic nutrient and organic carbon from wastewater of Binh Dien market using the green alga Chlorella sp.
Traditional markets play a major role in socio-economics and constitutes a significant aspect of Vietnamese culture. However, wastewater streams discharged from the markets are generally characterized by a lot of inorganic nutrients and organic substances originated from fresh food processing units. They could lead to serious water contamination if discharged without proper treatment. This study applied microalgae Chlorella sp. for eliminating inorganic nutrients (NO3--N, NH4+-N and PO43--P) and organic carbon (Chemical oxygen demand-COD) from wastewater of the Binh Dien market. The removal efficiencies reached for NH4+-N > 86%, for NO3--N > 72%, and for PO43--P > 69%, respectively, at algal density of 49 x 104 cell mL-1, and for COD > 96% at algal density of 35 x 104 cell mL-1 after five cultivating days. The effluence satisfied the Vietnamese standard, column B, of the National technical regulation on industrial wastewater (QCVN 40:2011/BTNMT). The results demonstrated that the culture system composed of green algal Chlorella sp. could be a potential candidate for the removal of nutrients and organic carbon by a wastewater treatment process from the Binh Dien market
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