11,039 research outputs found
Synchronization of Excitatory Neurons with Strongly Heterogeneous Phase Responses
In many real-world oscillator systems, the phase response curves are highly
heterogeneous. However, dynamics of heterogeneous oscillator networks has not
been seriously addressed. We propose a theoretical framework to analyze such a
system by dealing explicitly with the heterogeneous phase response curves. We
develop a novel method to solve the self-consistent equations for order
parameters by using formal complex-valued phase variables, and apply our theory
to networks of in vitro cortical neurons. We find a novel state transition that
is not observed in previous oscillator network models.Comment: 4 pages, 3 figure
Luntiang Basura (Green Wastes): A Case Study of Three Filipino Ecopreneurs in Upcycling
Currently, the Philippines is facing the challenges of devastating disasters brought about by accelerated global warming that continuously fuel the unthinkable climate change problems. Pollution has been identified as one of the major contributors to global warming. In the light of this gargantuan problem, alternative business processes must be resorted to for humankind to continue our existence in this planet. This paper aims to show, by way of a case study, that engaging in upcycling business, a more creative and upscale recycling, can be financially rewarding, socially responsible and at the same time help protect the environment by impacting the zero-waste campaign in a major manner â i.e., helping solve the solid waste problem. The case study features three well-known, passionate ecopreneur/upcyclist subjects who concretize and attest to the sustainability of the environment by using wastes as primary raw material inputs in their production process, producing beautiful artisan goods that command high price in the market; thus, providing desired profitability forthe company.
Keywords: ecopreneurs, green wastes, upcycling
Spin susceptibility of charge ordered YBa2Cu3Oy across the upper critical field
The value of the upper critical field Hc2, a fundamental characteristic of
the superconducting state, has been subject to strong controversy in high-Tc
copper-oxides. Since the issue has been tackled almost exclusively by
macroscopic techniques so far, there is a clear need for local-probe
measurements. Here, we use 17O NMR to measure the spin susceptibility
of the CuO2 planes at low temperature in charge ordered
YBa2Cu3Oy. We find that increases (most likely linearly) with
magnetic field H and saturates above field values ranging from 20 to 40 T. This
result is consistent with Hc2 values claimed by G. Grissonnanche et al. [Nat.
Commun. 5, 3280 (2014)] and with the interpretation that the
charge-density-wave (CDW) reduces Hc2 in underdoped YBa2Cu3Oy. Furthermore, the
absence of marked deviation in at the onset of long-range CDW
order indicates that this Hc2 reduction and the Fermi-surface reconstruction
are primarily rooted in the short-range CDW order already present in zero
field, not in the field-induced long-range CDWorder. Above Hc2, the relatively
low values of at T=2 K show that the pseudogap is a ground-state
property, independent of the superconducting gap.Comment: To appea
Tissue-specific expression of high-voltage-activated dihydropyridine-sensitive L-type calcium channels
The cloning of the cDNA for the α1 subunit of L-type calcium channels revealed that at least two genes (CaCh1 and CaCh2) exist which give rise to several splice variants. The expression of mRNA for these α1 subunits and the skeletal muscle α2/ÎŽ, ÎČ and Îł subunits was studied in rabbit tissues and BC3H1 cells. Nucleic-acid-hybridization studies showed that the mRNA of all subunits are expressed in skeletal muscle, brain, heart and aorta. However, the α1-, ÎČ- and Îł-specific transcripts had different sizes in these tissues. Smooth muscle and heart contain different splice variants of the CaCh2 gene. The α1, ÎČ and Îł mRNA are expressed together in differentiated but not in proliferating BC3H1 cells. A probe specific for the skeletal muscle α2/ÎŽ subunit did not hybridize to poly(A)-rich RNA from BC3H1 cells. These results suggest that different splice variants of the genes for the α1, ÎČ and Îł subunits exist in tissues containing L-type calcium channels, and that their expression is regulated in a coordinate manner
NMR evidence for inhomogeneous glassy behavior driven by nematic fluctuations in iron arsenide superconductors
We present As nuclear magnetic resonance spin-lattice and spin-spin
relaxation rate data in Ba(FeCo)As and
Ba(FeCu)As as a function of temperature, doping and
magnetic field. The relaxation curves exhibit a broad distribution of
relaxation rates, consistent with inhomogeneous glassy behavior up to 100 K.
The doping and temperature response of the width of the dynamical heterogeneity
is similar to that of the nematic susceptibility measured by elastoresistance
measurements. We argue that quenched random fields which couple to the nematic
order give rise to a nematic glass that is reflected in the spin dynamics.Comment: Accepted to Physical Review
Are short-term variations in solar oscillation frequencies the signature of a second solar dynamo?
In addition to the well-known 11-year solar cycle, the Sun's magnetic
activity also shows significant variation on shorter time scales, e.g. between
one and two years. We observe a quasi-biennial (2-year) signal in the solar
p-mode oscillation frequencies, which are sensitive probes of the solar
interior. The signal is visible in Sun-as-a-star data observed by different
instruments and here we describe the results obtained using BiSON, GOLF, and
VIRGO data. Our results imply that the 2-year signal is susceptible to the
influence of the main 11-year solar cycle. However, the source of the signal
appears to be separate from that of the 11-year cycle. We speculate as to
whether it might be the signature of a second dynamo, located in the region of
near-surface rotational shear.Comment: 6 pages, 2 figures, proceedings for SOHO-24/GONG 2010 conference, to
be published in JPC
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