Electron pairing in the vast majority of superconductors follows the Bardeen-Cooper-Schrieffer theory of superconductivity, which describes the condensation of electrons into pairs with antiparallel ...spins in a singlet state with an s-wave symmetry. Unconventional superconductivity was predicted in single-layer graphene (SLG), with the electrons pairing with a p-wave or chiral d-wave symmetry, depending on the position of the Fermi energy with respect to the Dirac point. By placing SLG on an electron-doped (non-chiral) d-wave superconductor and performing local scanning tunnelling microscopy and spectroscopy, here we show evidence for a p-wave triggered superconducting density of states in SLG. The realization of unconventional superconductivity in SLG offers an exciting new route for the development of p-wave superconductivity using two-dimensional materials with transition temperatures above 4.2 K.
Abstract
We present results from a stand-alone simulation of electron single Coulomb scattering as implemented completely on an Field Programmable Gate Array (FPGA) architecture and compared with an ...identical simulation on a standard CPU. FPGA architectures offer unprecedented speed-up capability for Monte Carlo simulations, however with the caveats of lengthy development cycles and resource limitation, particularly in terms of on-chip memory and DSP blocks. As a proof of principle of acceleration on an FPGA, we chose a single scattering process of electrons in water at an energy of 6 MeV. The initial code-base was implemented in C++ and optimised for CPU processing. To measure the potential performance gains of FPGAs compared to modern multi-core CPUs we computed 100M histories of a 6 MeV electron interacting in water. Without performing any hardware-specific optimisation, the results show that the FPGA implementation is over 110 times faster than an optimised parallel implementation running on 12 CPU-cores, and over 270 times faster than a sequential single-core CPU implementation. The results on both architectures were statistically equivalent. The successful implementation and acceleration results are very encouraging for the future exploitation of more sophisticated Monte Carlo simulation on FPGAs for High Energy Physics applications.
We report a spin valve with a few-layer graphene flake bridging highly spin-polarized La_{0.67}Sr_{0.33}MnO_{3} electrodes, whose surfaces are kept clean during lithographic definition. Sharp ...magnetic switching is verified using photoemission electron microscopy with x-ray magnetic circular dichroism contrast. A naturally occurring high interfacial resistance ∼12 MΩ facilitates spin injection, and a large resistive switching (0.8 MΩ at 10 K) implies a 70-130 μm spin diffusion length that exceeds previous values obtained with sharp-switching electrodes.
Nature Communications 8: Article number: 14024 (2017); Published: 19 January 2017; Updated: 1 March 2017 The present address for U. Sassi is incorrect in this Article. This author does not have a ...present address. The correct full affiliation details for this author are given below: Cambridge Graphene Centre, University of Cambridge, Cambridge CB3 0FA, UK.
Substance P (SP) is possibly involved in the pathophysiology of depression and anxiety. We investigated interactions between antidepressants on SP-induced effects and their potential calcium-blocking ...activity in the isolated guinea pig ileum. All the antidepressants tested, except pargyline, moclobemide, mianserin, and reboxetine, were able to inhibit in a concentration-dependent manner the contraction induced by 100 nmol/L SP. Clomipramine, fluoxetine, maprotiline, and amitriptyline (all at 3 μmol/L) flattened the concentration-response curves to SP, resulting in a reduction of up to 59%, 63%, 32%, and 23%, respectively, of the maximum contractile effect. All the antidepressants tested (3 μmol/L), except pargyline, moclobemide, and mianserin, produced a rightward parallel shift of the concentration-response curve to CaCl
2
. The L-type selective calcium blocker nifedipine and the T-type selective mibefradil showed similar behaviour against both agonists used, SP and CaCl
2
. The relative order of potency was nifedipine (pA
2
, 7.6 ± 0.1) > clomipramine (pA
2
, 7.0 ± 0.1) > fluoxetine (pK
B
, 6.5 ± 0.1) = mibefradil (pK
B
, 6.6 ± 0.1) > amitriptyline (pK
B
, 6.3 ± 0.1) = maprotiline (pK
B
, 6.2 ± 0.1) > fluvoxamine (pK
B
, 5.9 ± 0.1). The data reported in the present study suggest that the antidepressants tested did not behave as competitive antagonists versus NK
1
-receptor subtypes, but their inhibitory action seems to be related to their calcium-blocking properties.
Celotno besedilo
Dostopno za:
DOBA, FSPLJ, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We present the science and technology roadmap for graphene, related two-dimensional crystals, and hybrid systems, targeting an evolution in technology, that might lead to impacts and benefits ...reaching into most areas of society. This roadmap was developed within the framework of the European Graphene Flagship and outlines the main targets and research areas as best understood at the start of this ambitious project. We provide an overview of the key aspects of graphene and related materials (GRMs), ranging from fundamental research challenges to a variety of applications in a large number of sectors, highlighting the steps necessary to take GRMs from a state of raw potential to a point where they might revolutionize multiple industries. We also define an extensive list of acronyms in an effort to standardize the nomenclature in this emerging field.
We present the science and technology roadmap for graphene, related two-dimensional crystals, and hybrid systems, targeting an evolution in technology, that might lead to impacts and benefits reaching into most areas of society.
1
The interaction of melatonin (N‐acetyl‐5‐methoxytryptamine) with 5‐hydroxytryptamine4 (5‐HT4) receptors and/or with melatonin receptors (ML1, ML2 sites) has been assessed in isolated strips of the ...guinea‐pig proximal colon. In the same preparation, the pharmacological profile of a series of melatonin agonists (2‐iodomelatonin, 6‐chloromelatonin, N‐acetyl‐5‐hydroxytryptamine (N‐acetyl‐5‐HT), 5‐methoxycarbonylamino‐N‐acetyltryptamine (5‐MCA‐NAT)) was investigated.
2
In the presence of 5‐HT1/2/3 receptor blockade with methysergide (1 μM) and ondansetron (10 μM), melatonin (0.1 nM–10 μM), 5‐HT (1 nM–1 μM) and the 5‐HT4 receptor agonist, 5‐methoxytryptamine (5‐MeOT: 1 nM–1 μM) caused concentration‐dependent contractile responses. 5‐HT and 5‐MeOT acted as full agonists with a potency (−log EC50) of 7.8 and 8.0, respectively. The potency value for melatonin was 8.7, but its maximum effect was only 58% of that elicited by 5‐HT.
3
Melatonin responses were resistant to atropine (0.1 μM), tetrodotoxin (0.3 μM), and to blockade of 5‐HT4 receptors by SDZ 205,557 (0.3 μM) and GR 125487 (3, 30 and 300 nM). The latter antagonist (3 nM) inhibited 5‐HT‐induced contractions with an apparent pA2 value of 9.6. GR 125487 antagonism was associated with 30% reduction of the 5‐HT response maximum. Contractions elicited by 5‐HT were not modified when melatonin (1 and 10 nM) was used as an antagonist.
4
Like melatonin, the four melatonin analogues concentration‐dependently contracted colonic strips. The rank order of agonist potency was: 2‐iodomelatonin (10.8) >6‐chloromelatonin (9.9) N‐acetyl‐5‐HT (9.8) 5‐MCA‐NAT (9.6) >melatonin (8.7), an order typical for ML2 sites. In comparison with the other agonists, 5‐MCA‐NAT had the highest intrinsic activity.
5
The melatonin ML1B receptor antagonist luzindole (0.3, 1 and 3 μM) had no effect on the concentration‐response curve to melatonin. Prazosin, an α‐adrenoceptor antagonist possessing moderate/high affinity for melatonin ML2 sites did not affect melatonin‐induced contractions at 0.1 μM. Higher prazosin concentrations (0.3 and 1 μM) caused a non‐concentration‐dependent depression of the maximal response to melatonin without changing its potency. Prazosin (0.1 and 1 μM) showed a similar depressant behaviour towards the contractile responses to 5‐MCA‐NAT.
6
In the guinea‐pig proximal colon, melatonin despite some structural similarity with the 5‐HT4 receptor agonist 5‐MeOT, does not interact with 5‐HT4 receptors (or with 5‐HT1/2/3 receptors). As indicated by the rank order of agonist potencies and by the inefficacy of luzindole, the most likely sites of action of melatonin are postjunctional ML2 receptors. However, this assumption could not be corroborated with the use of prazosin as this ‘ML2 receptor antagonist’ showed only a non‐concentration‐dependent depression of the maximal contractile response to both melatonin and 5‐MCA‐NAT. Further investigation with the use of truly selective antagonists at melatonin ML2 receptors is required to clarify this issue.
British Journal of Pharmacology (1997) 121, 1775–1781; doi:10.1038/sj.bjp.0701287
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