A novel zinc finger transcriptional repressor, ZNF224, interacts with the negative regulatory element (AldA-NRE) and inhibits gene expression

The interaction between the negative cis-element (AldA-NRE) and p97 repressor nuclear protein is a key step in modulating transcription of the human and mouse aldolase A (AldA) gene during the cell cycle and differentiation. In an attempt to clarify the role of transcriptional repression in regulating gene expression, we purified, from HeLa cells, the nuclear protein that specifically binds to the AldA negative regulatory element (NRE). Matrix-assisted laser desorption ionization-time of flight analysis and examination of protein profiles from the SwissProt database revealed that the previously defined p97 repressor is ZNF224, a zinc finger protein. We demonstrate that ZNF224, a Kruppel-like zinc finger transcription factor, is the repressor protein that specifically binds to the negative cis-element AldA-NRE and affects the AldA-NRE-mediated transcription

Quantum-locked key distribution at nearly the classical capacity rate

Quantum data locking is a protocol that allows for a small secret key to (un)lock an exponentially larger amount of information, hence yielding the strongest violation of the classical one-time pad encryption in the quantum setting. This violation mirrors a large gap existing between two security criteria for quantum cryptography quantified by two entropic quantities: the Holevo information and the accessible information. We show that the latter becomes a sensible security criterion if an upper bound on the coherence time of the eavesdropper's quantum memory is known. Under this condition we introduce a protocol for secret key generation through a memoryless qudit channel. For channels with enough symmetry, such as the d-dimensional erasure and depolarizing channels, this protocol allows secret key generation at an asymptotic rate as high as the classical capacity minus one bit.Comment: v2 is close to the published version and contains only the key distribution protocols (4+5 pages), an extended version of the direct communication protocol is posted in arXiv:1410.4748 Comments always welcom

Continuous-variable quantum enigma machines for long-distance key distribution

Quantum physics allows for unconditionally secure communication through insecure communication channels. The achievable rates of quantum-secured communication are fundamentally limited by the laws of quantum physics and in particular by the properties of entanglement. For a lossy communication line, this implies that the secret-key generation rate vanishes at least exponentially with the communication distance. We show that this fundamental limitation can be violated in a realistic scenario where the eavesdropper can store quantum information for only a finite, yet arbitrarily long, time. We consider communication through a lossy bononic channel (modeling linear loss in optical fibers) and we show that it is in principle possible to achieve a constant rate of key generation of one bit per optical mode over arbitrarily long communication distances.Comment: 13 pages. V2: new title, new result on active attacks, increased rigour in the security proo

The International Regulatory Regime on Capital Flows and Trade in Services

Capital controls and exchange restrictions are used to restrict international capital flows during economic crises. This paper looks at the legal implications of these restrictions and explores the current international regulatory framework applicable to international capital movements and current payments. It shows how international capital flows suffer from the lack of a comprehensive and coherent regulatory framework that would harmonize the patchwork of multilateral, regional, and bilateral treaties that currently regulate this issue.capital controls; exchange restrictions; international capital flows; economic crises

Comparison of Gabay-Toulouse and de Almeida-Thouless instabilities for the spin glass XY model in a field on sparse random graphs

Vector spin glasses are known to show two different kinds of phase transitions in presence of an external field: the so-called de Almeida-Thouless and Gabay-Toulouse lines. While the former has been studied to some extent on several topologies (fully connected, random graphs, finite-dimensional lattices, chains with long-range interactions), the latter has been studied only in fully connected models, which however are known to show some unphysical behaviors (e.g. the divergence of these critical lines in the zero-temperature limit). Here we compute analytically both these critical lines for XY spin glasses on random regular graphs. We discuss the different nature of these phase transitions and the dependence of the critical behavior on the field distribution. We also study the crossover between the two different critical behaviors, by suitably tuning the field distribution.Comment: 21 pages, 14 figures; added a long appendix with respect to v

A mechanical model of the smartphone's accelerometer

To increase the attention of students, several physics experiments can be performed at school, as well at home, by using the smartphone as laboratory tools. In the paper we describe a mechanical model of the smartphone's accelerometer, which can be used in classroom to allow students to better understand the principle of the accelerometer even by students at the beginning of the study in physics.Comment: 4 pages, 1 embedded figur

Cadherin-7 enhances Sonic Hedgehog signalling by preventing Gli3 repressor formation during neural tube patterning

Sonic Hedgehog (Shh) is a ventrally enriched morphogen controlling dorsoventral patterning of the neural tube. In the dorsal spinal cord, Gli3 protein bound to suppressor-of-fused (Sufu) is converted into Gli3 repressor (Gli3R), which inhibits Shh-target genes. Activation of Shh signalling prevents Gli3R formation, promoting neural tube ventralization. We show that cadherin-7 (Cdh7) expression in the intermediate spinal cord region is required to delimit the boundary between the ventral and the dorsal spinal cord. We demonstrate that Cdh7 functions as a receptor for Shh and enhances Shh signalling. Binding of Shh to Cdh7 promotes its aggregation on the cell membrane and association of Cdh7 with Gli3 and Sufu. These interactions prevent Gli3R formation and cause Gli3 protein degradation. We propose that Shh can act through Cdh7 to limit intracellular movement of Gli3 protein and production of Gli3R, thus eliciting more efficient activation of Gli-dependent signalling