Digital electric field induced switching of plasmonic nanorods using an electro-optic fluid fiber

We demonstrate the digital electric field induced switching of plasmonic nanorods between 1 and 0 orthogonal aligned states using an electro-optic fluid fiber component. We show by digitally switching the nanorods, that thermal rotational diffusion of the nanorods can be circumvented, demonstrating an approach to achieve submicrosecond switching times. We also show, from an initial unaligned state, that the nanorods can be aligned into the applied electric field direction in 110 nanoseconds. The high-speed digital switching of plasmonic nanorods integrated into an all-fiber optical component may provide novel opportunities for remote sensing and signaling applications

Quantum key distribution session with 16-dimensional photonic states

The secure transfer of information is an important problem in modern telecommunications. Quantum key distribution (QKD) provides a solution to this problem by using individual quantum systems to generate correlated bits between remote parties, that can be used to extract a secret key. QKD with D-dimensional quantum channels provides security advantages that grow with increasing D. However, the vast majority of QKD implementations has been restricted to two dimensions. Here we demonstrate the feasibility of using higher dimensions for real-world quantum cryptography by performing, for the first time, a fully automated QKD session based on the BB84 protocol with 16-dimensional quantum states. Information is encoded in the single-photon transverse momentum and the required states are dynamically generated with programmable spatial light modulators. Our setup paves the way for future developments in the field of experimental high-dimensional QKD.Comment: 8 pages, 3 figure

The Lomagundi-Jatuli carbon isotopic event recorded in the marble of the Tandilia System basement, Río de la Plata Craton, Argentina

The “Lomagundi-Jatuli event” corresponds to the most important δ13C positive anomaly (≥5‰) globally reported in Palaeoproterozoic marine carbonates (between ∼2.30 and 2.06 Ga). In the Tandilia System (Argentina), Río de la Plata Craton, this event was recorded in the basement marble of the San Miguel area. The calcite-diopside marble, hosted by biotite gneiss and intruded by 2.12 Ga garnet-leucogranite, was metamorphosed in amphibolite facies during the Transamazonian Cycle. PAAS-normalised rare-earth elements (REE) and Y for the carbonate rocks are HREE-enriched and display positive Eu and Y anomalies, typical of primary precipitates from a mixed hydrothermal-marine environment carbonate. Additionally, a truly negative Ce anomaly for all the samples indicates that the depositional environment was oxidising. Positive δ13C values ranging from +5.90 to +4.30‰ (V-PDB), and δ18O from +17.45 to +13.84‰ (V-SMOW) were determined in this marble, both gradually decreasing towards the contact with the leucogranites. These values indicate that devolatilization reactions took place during the crystallisation of a wollastonite-vesuvianite-grossular-diopside skarn generated by the leucogranite intrusions into the marble. δ18O values obtained from diopside and calcite crystals, in the marble sectors furthest from the contacts with leucogranite, allowed a 663–623 °C formation temperature to be calculated, considering oxygen in a calcite-diopside geothermometric pair. These temperatures are consistent with the metamorphic degree (amphibolite facies) reached in this portion of the basement. Although the San Miguel marble shows petrographic and mineralogical evidence of regional and contact metamorphism, important geochemical and isotopic characteristics, together with its estimated Palaeoproterozoic age, indicate that the marble protolith was a marine carbonate deposited during the “Lomagundi-Jatuli event”.Fil: Lajoinie, Maria Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Recursos Minerales. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Recursos Minerales; ArgentinaFil: Lanfranchini, Mabel Elena. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Recursos Minerales. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Recursos Minerales; ArgentinaFil: Recio, C.. Universidad de Salamanca; EspañaFil: Sial, A.N.. Federal University of Pernambuco; BrasilFil: Cingolani, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; ArgentinaFil: Ballivian Justiniano, Carlos Alberto. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Recursos Minerales. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Recursos Minerales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Etcheverry, Ricardo Oscar. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Recursos Minerales. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Recursos Minerales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentin

Vanadium Compounds : Their Action on Alkaline Phosphatase Activity

The direct effect of different vanadium compounds upon alkaline phosphatase (ALP) activity was investigated~ Vanadate and vanadyl inhibited both the soluble and particulate ALP activity from UMR.106 cells and front bovine intestinal ALP. We have also shown the inhibition of ALP activity in the soluble fraction of osteoblasts by peroxo and hydroperoxo vanadium compounds. ALP activity in the particulate fraction was not inhibited by these species; nor was the bovine intestinal ALP. Using inhibitors of Tyr-phosphatase (PTPases), the soluble ALP was partially characterized as a PTPase. The major activity in the particulate fraction represents the bone-specific ALPactivity. This study demonstrates that different forms of vanadium are direct inhibitors of ALP activity. This effect is dependent on the enzymatic activity investigated and on the origin of the ALP.Facultad de Ciencias Médica

Insulin-mimetic action of vanadium compounds on osteoblast-like cells in culture

Vanadium compounds mimic insulin actions in different cell types. The present study concerns the insulin-like effects of three vanadium(V) derivatives and one vanadium(IV) complex on osteoblast-like (UMR106 and MC3T3E1) cells in culture. The vanadium oxalate and vanadium citrate complexes hydrolyzed completely under the culture conditions, whereas more than 40% of the vanadium tartrate and nitrilotriacetate complexes remained. Vanadate, as well as vanadium oxalate, citrate, and tartrate complexes enhanced cell proliferation (as measured by the crystal violet assay), glucose consumption, and protein content in UMR106 and MC3T3E1 osteoblast-like cells. The vanadium nitrilotriacetate complex (the only peroxo complex tested) stimulated cell proliferation in UMR106 but not in MC3T3E1 cells. This derivative strongly transformed the morphology of the MC3T3E1 cells. All vanadium(V) compounds inhibited cell differentiation (alkaline phosphatase activity) in UMR106 cells. Our data are consistent with the interpretation that vanadium oxalate and citrate complexes hydrolyze to vanadate. Vanadium nitrilotriacetate would appear to be toxic for normal MC3T3E1 osteoblasts. In contrast, the vanadium tartrate complex induced a proliferative effect; however, it did not alter cell differentiation

Insulin-mimetic action of vanadium compounds on osteoblast-like cells in culture

Vanadium compounds mimic insulin actions in different cell types. The present study concerns the insulin-like effects of three vanadium(V) derivatives and one vanadium(IV) complex on osteoblast-like (UMR106 and MC3T3E1) cells in culture. The vanadium oxalate and vanadium citrate complexes hydrolyzed completely under the culture conditions, whereas more than 40% of the vanadium tartrate and nitrilotriacetate complexes remained. Vanadate, as well as vanadium oxalate, citrate, and tartrate complexes enhanced cell proliferation (as measured by the crystal violet assay), glucose consumption, and protein content in UMR106 and MC3T3E1 osteoblast-like cells. The vanadium nitrilotriacetate complex (the only peroxo complex tested) stimulated cell proliferation in UMR106 but not in MC3T3E1 cells. This derivative strongly transformed the morphology of the MC3T3E1 cells. All vanadium(V) compounds inhibited cell differentiation (alkaline phosphatase activity) in UMR106 cells. Our data are consistent with the interpretation that vanadium oxalate and citrate complexes hydrolyze to vanadate. Vanadium nitrilotriacetate would appear to be toxic for normal MC3T3E1 osteoblasts. In contrast, the vanadium tartrate complex induced a proliferative effect; however, it did not alter cell differentiation.Facultad de Ciencias Exacta

Proliferative and morphological changes induced by vanadium compounds on Swiss 3T3 fibroblasts

Vanadium compounds are shown to have a mitogenic effect on fibroblast cells. The effects of vanadate, vanadyl and pervanadate on the proliferation and morphological changes of Swiss 3T3 cells in culture are compared. Vanadium derivatives induced cell proliferation in a biphasic manner, with a toxic-like effect at doses over 50 mM, after 24 h of incubation. Vanadyl and vanadate were equally potent at 2.5–10 mM. At 50 mM vanadate inhibited cell proliferation, whereas slight inhibition was observed at 100 mM of vanadyl. At 10 mM pervanadate was as potent as vanadate and vanadyl in stimulating fibroblast proliferation, but no effect was observed at lower concentrations. A pronounced cytotoxic-like effect was induced by pervanadate at 50 mM. All of these effects were accompanied by morphological changes: transformation of fibroblast shape from polygonal to fusiform; retraction with cytoplasm condensation; and loss of lamellar processes. The magnitude of these transformations correlates with the potency of vanadium derivatives to induce a cytotoxic-like effect: pervanadate > vanadate > vanadyl. These data suggest that the oxidation state and coordination geometry of vanadium determine the degree of the cytotoxicit

Insulin-mimetic action of vanadium compounds on osteoblast-like cells in culture

Vanadium compounds mimic insulin actions in different cell types. The present study concerns the insulin-like effects of three vanadium(V) derivatives and one vanadium(IV) complex on osteoblast-like (UMR106 and MC3T3E1) cells in culture. The vanadium oxalate and vanadium citrate complexes hydrolyzed completely under the culture conditions, whereas more than 40% of the vanadium tartrate and nitrilotriacetate complexes remained. Vanadate, as well as vanadium oxalate, citrate, and tartrate complexes enhanced cell proliferation (as measured by the crystal violet assay), glucose consumption, and protein content in UMR106 and MC3T3E1 osteoblast-like cells. The vanadium nitrilotriacetate complex (the only peroxo complex tested) stimulated cell proliferation in UMR106 but not in MC3T3E1 cells. This derivative strongly transformed the morphology of the MC3T3E1 cells. All vanadium(V) compounds inhibited cell differentiation (alkaline phosphatase activity) in UMR106 cells. Our data are consistent with the interpretation that vanadium oxalate and citrate complexes hydrolyze to vanadate. Vanadium nitrilotriacetate would appear to be toxic for normal MC3T3E1 osteoblasts. In contrast, the vanadium tartrate complex induced a proliferative effect; however, it did not alter cell differentiation.Facultad de Ciencias Exacta

Proliferative and morphological changes induced by vanadium compounds on Swiss 3T3 fibroblasts

Vanadium compounds are shown to have a mitogenic effect on fibroblast cells. The effects of vanadate, vanadyl and pervanadate on the proliferation and morphological changes of Swiss 3T3 cells in culture are compared. Vanadium derivatives induced cell proliferation in a biphasic manner, with a toxic-like effect at doses over 50 mM, after 24 h of incubation. Vanadyl and vanadate were equally potent at 2.5–10 mM. At 50 mM vanadate inhibited cell proliferation, whereas slight inhibition was observed at 100 mM of vanadyl. At 10 mM pervanadate was as potent as vanadate and vanadyl in stimulating fibroblast proliferation, but no effect was observed at lower concentrations. A pronounced cytotoxic-like effect was induced by pervanadate at 50 mM. All of these effects were accompanied by morphological changes: transformation of fibroblast shape from polygonal to fusiform; retraction with cytoplasm condensation; and loss of lamellar processes. The magnitude of these transformations correlates with the potency of vanadium derivatives to induce a cytotoxic-like effect: pervanadate > vanadate > vanadyl. These data suggest that the oxidation state and coordination geometry of vanadium determine the degree of the cytotoxicity.Facultad de Ciencias Exacta