256 research outputs found
Enhancement of Tc in the Superconductor-Insulator Phase Transition on Scale-Free Networks
A road map to understand the relation between the onset of the
superconducting state with the particular optimum heterogeneity in granular
superconductors is to study a Random Tranverse Ising Model on complex networks
with a scale-free degree distribution regularized by and exponential cutoff
p(k) \propto k^{-\gamma}\exp[-k/\xi]. In this paper we characterize in detail
the phase diagram of this model and its critical indices both on annealed and
quenched networks. To uncover the phase diagram of the model we use the tools
of heterogeneous mean-field calculations for the annealed networks and the most
advanced techniques of quantum cavity methods for the quenched networks. The
phase diagram of the dynamical process depends on the temperature T, the
coupling constant J and on the value of the branching ratio / where
k is the degree of the nodes in the network. For fixed value of the coupling
the critical temperature increases linearly with the branching ration which
diverges with the increasing cutoff value \xi or value of the \gamma exponent
\gamma< 3. This result suggests that the fractal disorder of the
superconducting material can be responsible for an enhancement of the
superconducting critical temperature. At low temperature and low couplings T<<1
and J<<1, instead, we observe a different behavior for annealed and quenched
networks. In the annealed networks there is no phase transition at zero
temperature while on quenched network we observe a Griffith phase dominated by
extremely rare events and a phase transition at zero temperature. The Griffiths
critical region, nevertheless, is decreasing in size with increasing value of
the cutoff \xi of the degree distribution for values of the \gamma exponents
\gamma< 3.Comment: (17 pages, 3 figures
Phase diagram of the Bose-Hubbard Model on Complex Networks
Critical phenomena can show unusual phase diagrams when defined in complex
network topologies. The case of classical phase transitions such as the
classical Ising model and the percolation transition has been studied
extensively in the last decade. Here we show that the phase diagram of the
Bose-Hubbard model, an exclusively quantum mechanical phase transition, also
changes significantly when defined on random scale-free networks. We present a
mean-field calculation of the model in annealed networks and we show that when
the second moment of the average degree diverges the Mott-insulator phase
disappears in the thermodynamic limit. Moreover we study the model on quenched
networks and we show that the Mott-insulator phase disappears in the
thermodynamic limit as long as the maximal eigenvalue of the adjacency matrix
diverges. Finally we study the phase diagram of the model on Apollonian
scale-free networks that can be embedded in 2 dimensions showing the extension
of the results also to this case.Comment: (6 pages, 4 figures
SYNTHESIS AND BIOLOGICAL ACTIVITIES OF SOME INDOLE ANALOGUES CONTAINING TRIAZOLE-5-THIOL AND THIAZOLOTRIAZOLE SYSTEMS
Objective: The present study aims at the synthesis and evaluation of antimicrobial and antioxidant activities of indole analogues incorporated with triazole and thiazolotriazole moieties.
Methods: The newly synthesized compounds were screened for their antimicrobial activity by cup-plate method. Antioxidant activity by three different methods viz.,1,1-diphenyl-2-picryl hydrazil (DPPH) radical scavenging activity (RSA), ferric ion (Fe3+) reducing power (FRAP) and ferrous (Fe2+) ion metal chelating activity were appraised by calorimetric method using UV-Visible spectrophotometer.
Results: The structures of all the newly synthesized compounds have been established on the basis of their IR, 1HNMR, [13]CNMR and mass spectral studies and elemental analysis. Compound 4a showed good radical scavenging activity (RSA), 4b showed good ferric ion (Fe3+) reducing antioxidant power (FRAP) and compounds 3c and 4a exhibited good ferrous ion metal chelating activity. Whereas compound 3b showed good antibacterial activity against P. aeruginosa, 4a against S. aureus and 4c against E. coli. While for the antifungal activity compound 3a was good against A. oryzae, 3c against A. nizer and 4a against A. flavus.
Conclusion: Antimicrobial and antioxidant activity results of the newly synthesized compounds indicate that some of the compounds showed better antimicrobial and antioxidant activities with reference to the standard drugs
Effect of Prematurity, Birthweight, Maternal Stress, Socio-economic Status, and Mother-Child Intimacy on the Development of Preschool Children in Surakarta
Background: Monitoring child development is an important step to prepare healthy children from the earliest age, both physically, spiritually, and socially. Monitoring child development can be done in the kindergarten. Some kindergartens in Surakarta, however, have not implemented child development monitoring program. This study aims to determine the effect of prematurity, birthweight, maternal stress, socio-economic status, and mother-child intimacy, on the development of preschool children.Subjects and Method: This was an analytical observational study using case control design. The study was carried out at 7 kindergartens (TK) in Surakarta, Central Java: TK Negeri Pembina, TK Gaya Baru III, TK Kristen Ngasinan, TK Islam Bakti 6, TK Advent, TK Warga and TK Kanisius Imakulata, from May to June 2017. A sample of 120 children aged 5-6 years old attending kindergartens were selected for this study by fixed exposure sampling, i.e. selection based on prematurity status. The dependent variable was child development. The independent variables were prematurity, birthweight, maternal stress, maternal employment status, maternal education, family income, parenting time, and mother-child intimacy. The data were collected by a set of pre-tested questionnaire. Child development was measured by development pre-screening questionnaire (KPSP). Nutritional status was obtained from maternal and child health recording book. Path analysis was employed for data analysis.Results: Child development was directly affected by prematurity (b=0.29; SE=0.07; p<0.001), birthweight (b=0.04; SE= 0.18; p=0.007), maternal employment (b=0.46; SE=0.20; p=0.020), maternal education (b=0.65; SE=0.21; p=0.002), family income (b=0.01; SE=0.01; p=0.015), and mother-child intimacy (b=0.26; SE=0.05; p<0.001). Family income was affected by maternal employment (b=23.37; SE=5.52; p<0.001) and maternal education (b=23.50; SE=5.79; p<0.001). Mother-child intimacy was affected by maternal stress (b=0.01; SE=0.01; p=0.052) and parenting time (b=0.56; SE=0.05; p<0.001).Conclusions: Child development is directly affected by prematurity, birthweight, maternal employment, maternal education, family income, and mother-child intimacy.Keywords: child development, prematurity, birthweight, socio-economic status, maternal stress, mother-child intimacyCorrespondence: Silfia Angela N Halu. s Program in Public Health, Sebelas Maret University, Surakarta. Email: [email protected]. Mobile: +6285338395484.Journal of Maternal and Child Health (2017), 2(3): 187-199https://doi.org/10.26911/thejmch.2017.02.03.0
Connect and win: The role of social networks in political elections
Many real systems are made of strongly interacting networks, with profound consequences on their dynamics. Here, we consider the case of two interacting social networks and, in the context of a simple model, we address the case of political elections. Each network represents a competing party and every agent, on the election day, can choose to be either active in one of the two networks (vote for the corresponding party) or to be inactive in both (not vote). The opinion dynamics during the election campaign is described through a simulated annealing algorithm. We find that for a large region of the parameter space the result of the competition between the two parties allows for the existence of pluralism in the society, where both parties have a finite share of the votes. The central result is that a densely connected social network is key for the final victory of a party. However, small committed minorities can play a crucial role, and even reverse the election outcome
Self-organization towards optimally interdependent networks by means of coevolution
Coevolution between strategy and network structure is established as a means to arrive at the optimal conditions needed to resolve social dilemmas. Yet recent research has highlighted that the interdependence between networks may be just as important as the structure of an individual network. We therefore introduce the coevolution of strategy and network interdependence to see whether this can give rise to elevated levels of cooperation in the prisonerʼs dilemma game. We show that the interdependence between networks self-organizes so as to yield optimal conditions for the evolution of cooperation. Even under extremely adverse conditions, cooperators can prevail where on isolated networks they would perish. This is due to the spontaneous emergence of a two-class society, with only the upper class being allowed to control and take advantage of the interdependence. Spatial patterns reveal that cooperators, once arriving at the upper class, are much more competent than defectors in sustaining compact clusters of followers. Indeed, the asymmetric exploitation of interdependence confers to them a strong evolutionary advantage that may resolve even the toughest of social dilemmas
A disease-driver population within interstitial cells of human calcific aortic valves identified via single-cell and proteomic profiling.
Annexin A1-dependent tethering promotes extracellular vesicle aggregation revealed with single–extracellular vesicle analysis
Extracellular vesicles (EVs) including plasma membrane-derived microvesicles and endosomal-derived exosomes aggregate by unknown mechanisms, forming microcalcifications that promote cardiovascular disease, the leading cause of death worldwide. Here, we show a framework for assessing cell-independent EV mechanisms in disease by suggesting that annexin A1 (ANXA1)-dependent tethering induces EV aggregation and microcalcification. We present single-EV microarray, a method to distinguish microvesicles from exosomes and assess heterogeneity at a single-EV level. Single-EV microarray and proteomics revealed increased ANXA1 primarily on aggregating and calcifying microvesicles. ANXA1 vesicle aggregation was suppressed by calcium chelation, altering pH, or ANXA1 neutralizing antibody. ANXA1 knockdown attenuated EV aggregation and microcalcification formation in human cardiovascular cells and acellular three-dimensional collagen hydrogels. Our findings explain why microcalcifications are more prone to form in vulnerable regions of plaque, regulating critical cardiovascular pathology, and likely extend to other EV-associated diseases, including autoimmune and neurodegenerative diseases and cancer
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