Hacking commercial quantum cryptography systems by tailored bright illumination

The peculiar properties of quantum mechanics allow two remote parties to communicate a private, secret key, which is protected from eavesdropping by the laws of physics. So-called quantum key distribution (QKD) implementations always rely on detectors to measure the relevant quantum property of single photons. Here we demonstrate experimentally that the detectors in two commercially available QKD systems can be fully remote-controlled using specially tailored bright illumination. This makes it possible to tracelessly acquire the full secret key; we propose an eavesdropping apparatus built of off-the-shelf components. The loophole is likely to be present in most QKD systems using avalanche photodiodes to detect single photons. We believe that our findings are crucial for strengthening the security of practical QKD, by identifying and patching technological deficiencies.Comment: Revised version, rewritten for clarity. 5 pages, 5 figures. To download the Supplementary information (which is in open access), go to the journal web site at http://dx.doi.org/10.1038/nphoton.2010.21

Multilayer coatings based on CrN/Cr for molds of plastics

Many problems related to the efficiency of tribological steel substrates have been improved by theintroduction of ceramic coatings based on nitrides of transition metals, as applied by physical vapordeposition (PVD) [1]. Multilayer PVD coatings are currently being developed so as to achieve a furtherincrease in performance from both tribological and corrosion resistance. The principle of the method is tocreate a coating characterized by a high number of layers stacked in such a way as to block the growth of thecolumnar structure with high porosity. In this work a series of mono-and multilayer coatings were taken intoaccount. These consist of CrN and Cr multilayers coatings made in a deposition chamber using cathodic arcPVD at the company CRT. As steel substrate AISI H11was chosen in the following surface state conditions:mirror finish, electroeroded, ground and sandblaste

Doxorubicin and congo red effectiveness on prion infectivity in golden Syrian hamster

The effect of doxorubicin and Congo Red on prion protein (PrP) infectivity in experimental scrapie was studied to better understand the effect of these compounds in prion diseases and to establish whether a dose-response correlation exists for Congo Red. This was performed in order to test the effectiveness of compounds that may easily be used in human prion diseases. Brain homogenate containing membrane bound PrPSc monomers was used as inoculum and was previously incubated with doxorubicin 10(-3) M and with increasing concentrations of Congo Red ranging from 10(-7) to 10(-2) M. This study shows for the first time that doxorubicin, and confirms that Congo Red, may interact with pathological PrP monomers modifying their infectious properties. Pre-incubation of infected brain homogenate with Congo Red resulted in prolonged incubation time and survival, independently of Congo Red concentration (p<0.05). Doxorubicin and Congo Red effects do not depend upon interaction with PrP amyloid material

Immunohistochemical and biochemical identification of MMP-2 in dentin

Matrix metalloproteinases (MMPs) play an important role in many biological and pathological processes because of their ability to degrade all extracellular matrix (ECM) components. The purpose of this study was to identify MMP-2 in human dentin by immunohistochemical and biochemical methods. Dentin cryo-fractured fragments were obtained from human sound teeth, partially decalcified in 0.5 M EDTA pH 7.4 for 30min and submitted to a pre-embedding immunolabeling technique, using primary monoclonal antibodies anti-MMP-2 and exposed to a secondary antibody conjugated with gold nano-particles. Observations were performed by means of a FEI-SEM. Furthermore,the presence of MMP-2 was correlatively assayed by a colorimetric assay system (Quantisir) that allows direct measurement of MMP-2 levels. The immunohistochemical analysis revealed an intricate three-dimensional network of type I collagen and positive immunolabeling patterns for MMP-2 showing its distribution along with the collagen fibrils. The colorimetric assay resulted in higher presence of MMP-2 in mineralized dentin, compared to the partially demineralized counterpart. The role and function of dentin MMPs is not well known, but they have shown to contribute to auto-degenerative processes in dentin, such as inflammation of dental pulp, progression of caries lesions. This study demonstrated using an immunohistochemical and a biochemical approach that MMP-2 is an intrinsic component of the human dentin organic matrix, with possible roles in dentin matrix turnover and degenerative processes

Noninvasive near-infrared live imaging of human adult mesenchymal stem cells transplanted in a rodent model of Parkinson’s disease

Background: We have previously shown that human mesenchymal stem cells (hMSCs) can reduce toxin-induced neurodegeneration in a well characterized rodent model of Parkinson's disease. However, the precise mechanisms, optimal cell concentration required for neuroprotection, and detailed cell tracking need to be defined. We exploited a near-infrared imaging platform to perform noninvasive tracing following transplantation of tagged hMSCs in live parkinsonian rats.Methods: hMSCs were labeled both with a membrane intercalating dye, emitting in the near-infrared 815 nm spectrum, and the nuclear counterstain, Hoechst 33258. Effects of near-infrared dye on cell metabolism and proliferation were extensively evaluated in vitro. Tagged hMSCs were then administered to parkinsonian rats bearing a 6-hydroxydopamine-induced lesion of the nigrostriatal pathway, via two alternative routes, ie, intrastriatal or intranasal, and the cells were tracked in vivo and ex vivo using near-infrared technology.Results: In vitro, NIR815 staining was stable in long-term hMSC cultures and did not interfere with cell metabolism or proliferation. A significant near-infrared signal was detectable in vivo, confined around the injection site for up to 14 days after intrastriatal transplantation. Conversely, following intranasal delivery, a strong near-infrared signal was immediately visible, but rapidly faded and was completely lost within 1 hour. After sacrifice, imaging data were confirmed by presence/absence of the Hoechst signal ex vivo in coronal brain sections. Semiquantitative analysis and precise localization of transplanted hMSCs were further performed ex vivo using near-infrared imaging.Conclusion: Near-infrared technology allowed longitudinal detection of fluorescent-tagged cells in living animals giving immediate information on how different delivery routes affect cell distribution in the brain. Near-infrared imaging represents a valuable tool to evaluate multiple outcomes of transplanted cells, including their survival, localization, and migration over time within the host brain. This procedure considerably reduces the number of animal experiments needed, as well as interindividual variability, and may favor the development of efficient therapeutic strategies promptly applicable to patients

A role for the ELAV RNA-binding proteins in neural stem cells : stabilization of Msi1 mRNA

Post-transcriptional regulation exerted by neural-specific RNA-binding proteins plays a pivotal role in the development and maintenance of the nervous system. Neural ELAV proteins are key inducers of neuronal differentiation through the stabilization and/or translational enhancement of target transcripts bearing the AU-rich elements (AREs), whereas Musashi-1 maintains the stem cell proliferation state by acting as a translational repressor. Since the gene encoding Musashi-1 (Msi1) contains a conserved ARE in its 3' untranslated region, the authors focused on the possibility of a mechanistic relation between ELAV proteins and Musashi-1 in cell fate commitment. Colocalization of neural ELAV proteins with Musashi-1 clearly shows that ELAV proteins are expressed at early stages of neural commitment, whereas interaction studies demonstrate that neural ELAV proteins exert an ARE-dependent binding activity on the Msi1 mRNA. This binding activity has functional effects, since the ELAV protein family member HuD is able to stabilize the Msi1 ARE-contg. mRNA in a sequence-dependent way in a deadenylation/degrdn. assay. Furthermore activation of the neural ELAV proteins by phorbol esters in human SH-SY5Y cells is assocd. with an increase of Musashi-1 protein content in the cytoskeleton. The authors propose that ELAV RNA-binding proteins exert an important post-transcriptional control on Musashi-1 expression in the transition from proliferation to neural differentiation of stem/progenitor cells

Effectiveness of a group-based psychosocial program to prevent depression and anxiety in older people attending primary health care centres: a randomised controlled trial

Background: Evidence about the effectiveness of psychosocial interventions to reduce the incidence of depression and anxiety and promote subjective well-being in older people is limited, particularly in Latin-American countries. This study thus aims to assess a program specifically designed to address this issue in persons aged 65 to 80 and attending primary health care centres. Method: Older people who use primary care centres are to be randomly assigned to the program or to a control group. Only independent users will be included; those having had a major depressive disorder or an anxiety disorder in the last 6 months will be excluded. The program is group based; it includes cognitive stimulation, expansion of social support networks and cognitive behaviour strategies. Depressive and anxiety symptoms and disorders, as well as psychological well-being, will be assessed using standardised instruments, once before implementing the program and later, after 18 and 36 weeks. Discussion: Primary care is a setting where interventions to improve mental health can be beneficial. Providing evidence-based programs that work with older people is a priority for public mental health

Na+,K+-ATPase of gastric cells A target of Helicobacter pylori cytotoxic activity

AbstractThe present study shows a direct impairing action of a cytotoxin-producing Helicobacter pylori strain on the Na+,K−-ATPase (evaluated as K+-dependent phosphatase activity) of human gastric epithelial cells in culture. The toxin itself is likely involved in this action which may also account for the cell edema found in vivo in Helicobacter pylori-colonized stomach

Phase stability and electronic structure of iridium metal at the megabar range

[EN] The 5d transition metals have attracted specific interest for high-pressure studies due to their extraordinary stability and intriguing electronic properties. In particular, iridium metal has been proposed to exhibit a recently discovered pressure-induced electronic transition, the so-called core-level crossing transition at the lowest pressure among all the 5d transition metals. Here, we report an experimental structural characterization of iridium by x-ray probes sensitive to both long- and short-range order in matter. Synchrotron-based powder x-ray diffraction results highlight a large stability range (up to 1.4 Mbar) of the low-pressure phase. The compressibility behaviour was characterized by an accurate determination of the pressure-volume equation of state, with a bulk modulus of 339(3) GPa and its derivative of 5.3(1). X-ray absorption spectroscopy, which probes the local structure and the empty density of electronic states above the Fermi level, was also utilized. The remarkable agreement observed between experimental and calculated spectra validates the reliability of theoretical predictions of the pressure dependence of the electronic structure of iridium in the studied interval of compressions.The authors thank the financial support of the Spanish Ministry of Science, Innovation and Universities, the Spanish Research Agency (AEI), the European Fund for Regional Development (FEDER) under Grant No. MAT2016-75586-C4-1/2-P and the Generalitat Valenciana under Grant Prometeo/2018/123 (EFIMAT). V. M. acknowledges the Juan de la Cierva fellowship (FJCI-2016-27921) and J.A.S. acknowledges the Ramón y Cajal fellowship program (RYC-2015-17482) and Spanish Mineco Project FIS2017-83295-P. We acknowledge the European Synchrotron Radiation Facility for provision of official research beamtimes, the Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linköping University (Faculty Grant SFO-Mat-LiU No 2009 00971), Knut and Alice Wallenbergs Foundation Project Strong Field Physics and New States of Matter CoTXS (2014 2019). The interpretation of theoretical results was supported by the Ministry of Science and High Education of the Russian Federation in the framework of Increase Competitiveness Program of NUST MISIS (No. K2-2019-001) implemented by a governmental decree dated 16 March 2013, No 211.Monteseguro, V.; Sans-Tresserras, JÁ.; Cuartero, V.; Cova, F.; Abrikosov, I.; Olovsson, W.; Popescu, C.... (2019). Phase stability and electronic structure of iridium metal at the megabar range. Scientific Reports. 9:1-9. https://doi.org/10.1038/s41598-019-45401-xS199Cynn, H., Klepeis, J. E., Yoo, C.-S. & Young, D. A. Osmium has the Lowest Experimentally Determined Compressibility. Phys. Rev. Lett. 88, 135701–135704 (2002).Döhring, T. et al. Prototyping iridium coated mirrors for x-ray astronomy. Proc. SPIE 10235, 1023504–1023511 (2017).Bednorz, J. G. & Müller, K. A. Possible high Tc superconductivity in the Ba−La−Cu−O system. Z. Phys. B: Condens. Matter 64, 189–193 (1986).Tokura, Y. & Nagaosa, N. Orbital Physics in Transition-Metal Oxides. Science 288, 462–468 (2000).Kobayashi, K.-I., Kimura, T., Sawada, H., Terakura, K. & Tokura, Y. Room-temperature magnetoresistance in an oxide material with an ordered double-perovskite structure. Nature (London) 395, 677–680 (1998).Hrubiak, R., Meng, Y. & Shen, G. Microstructures define melting of molybdenum at high pressures. Nature Commun. 8, 14562–14571 (2017).Cerenius, Y. & Dubrovinsky, L. Compressibility measurements on iridium. J. Alloys Compd. 306, 26–29 (2000).Grussendorff, S., Chetty, N. & Dreysse, H. Theoretical studies of iridium under pressure. J. Phys. Condens. Matter 15, 4127–4134 (2003).Burakovsky, L. et al. Ab initio phase diagram of iridium. Phys. Rev. B 94, 094112–094120 (2016).Dubrovinsky, L. et al. The most incompressible metal osmium at static pressures above 750 gigapascals. Nature 525, 226–229 (2015).Tal, A. A. et al. Pressure-induced crossing of the core levels in 5d metals. Phys. Rev. B 93, 205150–205156 (2016).Merkel, S. et al. Deformation of polycrystalline MgO at pressures of the lower mantle. J Geophys Res. 107, 2271–2287 (2002).Greenberg, E. et al. Pressure-Induced Site-Selective Mott Insulator-Metal Transition in Fe2O3. Phys. Rev. X 8, 031059–031071 (2018).Nemoshkalenko, V. V., Mil’man, V. Y., Zhalko-Titarenko, A. V., Antonov, V. N. & Shitikov, Y. L. Pis’ma Zh. Eksp Teor. Fiz 47, 295–297 (1988).Rehr, J. J. & Albers, R. C. Theoretical approaches to x-ray absorption fine structure. Rev. Mod. Phys. 72, 621–654 (2000).Poiarkova, A. V. & Rehr, J. J. Multiple-scattering x-ray-absorption fine-structure Debye-Waller factor calculations. Phys. Rev. B 59, 948–957 (1998).Glazyrin, K. et al. Importance of correlation effects in hcp iron revealed by a pressure-induced electronic topological transition. Phys. Rev. Lett. 110, 117206–117210 (2013).Sham, T. K. L-edge x-ray-absorption systematics of the noble metals Rh, Pd, and Ag and the main-group metals In and Sn: A study of the unoccupied density of states in 4d elements. Phys. Rev. B 31, 1888–1902 (1985).Leapman, R. D., Grunes, L. A. & Fejes, P. L. Study of the L23 edges in the 3d transition metals and their oxides by electron-energy-loss spectroscopy with comparisons to theory. Phys. Rev. B 26, 614–635 (1982).Choy, J.-H., Kim, D.-K., Hwang, S.-H., Demazeau, G. & Jung, D.-Y. the Ir-O Bond Covalency in Ionic Iridium Perovskites. J. Am. Chem. Soc. 117, 8557–8566 (1995).Clancy, J. P. et al. Spin-orbit coupling in iridium-based 5d compounds probed by x-ray absorption spectroscopy. Phys. Rev. B 86, 195131- (2012).Snigirev, A., Kohn, V., Snigireva, I. & Lengeler, B. A compound refractive lens for focusing high-energy X-rays. Nature 384, 49–51 (1996).Dewaele, A., Loubeyre, P. & Mezouar, M. Equations of state of six metals above 94 GPa. Phys. Rev. B 70, 094112–094119 (2004).Prescher, C. & Prakapenka, V. B. DIOPTAS: a program for reduction of twodimensional X-ray diffraction data and data exploration. High Pressure Res. 35, 223–230 (2015).Toby, B. H. & Von Dreele, R. B. GSAS-II: the genesis of a modern open-source all-purpose crystallography software package. J. Appl. Cryst. 46(2), 544–549 (2013).Birch, F. Finite strain isotherm and velocities for single‐crystal and polycrystalline NaCl at high pressures and 300 K. J. Geophys. Res. 83, 1257–1268 (1978).Angel, R. J., González-Platas, J. & Alvaro, M. EosFit7c and a Fortran module (library) for equation of state calculations. Z. Kristallogr. 229, 405–419 (2014).Mathon, O. et al. The time-resolved and extreme conditions XAS (TEXAS) facility at the European Synchrotron Radiation Facility: the general-purpose EXAFS bending-magnet beamline BM23. J. Synchrotron Radiat. 22, 1548–1554 (2015).Ohfuji, H. et al. "Natural occurrence of pure nano-polycrystalline diamond from impact crater". Scientific Reports. 5: 14702.s, L. D., 2000. J. Alloys Compd. 306, 26–29 (2015).Ravel, B. & Newville, M. ATHENA, ARTEMIS, HEPHAESTUS: data analysis for X-ray absorption spectroscopy using IFEFFIT. J. Synchrotron Radiat. 12, 537–577 (2005).Blaha, P., Schwarz, K., Madsen, G. K. H., Kvasnicka, D. & Luitz, J. WIEN2K, An Augmented Plane Wave + Local Orbitals Program for Calculating Crystal Properties. Karlheinz Schwarz, Techn. Universität, Wien, Austria. (2001).Perdew, J. P., Burke, S. & Ernzerhof, M. Generalized Gradient Approximation Made Simple. Phys. Rev. Lett. 77, 3865–3868 (1996)

NMR Metabolomics for Stem Cell type discrimination

Cell metabolism is a key determinant factor for the pluripotency and fate commitment of Stem Cells (SCs) during development, ageing, pathological onset and progression. We derived and cultured selected subpopulations of rodent fetal, postnatal, adult Neural SCs (NSCs) and postnatal glial progenitors, Olfactory Ensheathing Cells (OECs), respectively from the subventricular zone (SVZ) and the olfactory bulb (OB). Cell lysates were analyzed by proton Nuclear Magnetic Resonance (1H-NMR) spectroscopy leading to metabolites identification and quantitation. Subsequent multivariate analysis of NMR data by Principal Component Analysis (PCA), and Partial Least Square Discriminant Analysis (PLS-DA) allowed data reduction and cluster analysis. This strategy ensures the definition of specific features in the metabolic content of phenotypically similar SCs sharing a common developmental origin. The metabolic fingerprints for selective metabolites or for the whole spectra demonstrated enhanced peculiarities among cell types. The key result of our work is a neat divergence between OECs and the remaining NSC cells. We also show that statistically significant differences for selective metabolites characterizes NSCs of different ages. Finally, the retrived metabolome in cell cultures correlates to the physiological SC features, thus allowing an integrated bioengineering approach for biologic fingerprints able to dissect the (neural) SC molecular specificitie