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Fluorescent nanodiamonds
Get PDFFluorescent nanodiamonds are a promising and attractive platform for quantum technology due to the combination of outstanding properties of diamond color centers and the nanoscale size of crystals. It allows their integration with different types of photonic structures for quantum information and communication purposes as well as usage for sensing in various environments, including harsh conditions and biological systems. This chapter will discuss the fabrication methods of fluorescent nanodiamonds, the optical properties and specific features related to their nanosize and surface, and some key applications
Raising awareness to geo-hydrological hazard risks in African countries: A guide booklet for stakeholders, policy markers and the public at large
No full textUnlocking sand fly biodiversity in Nepal: Enhancing disease control through DNA-barcoding
No full textSand fly-borne diseases have a significant impact on global public health, although they are typically overlooked. In the Indian subcontinent, particularly in Nepal, India, and Bangladesh, over 46 cryptic species within the genera Phlebotomus and Sergentomyia play a key role in transmitting diseases such as visceral leishmaniasis (VL) and cutaneous leishmaniasis (CL) caused by the protozoan parasite Leishmania donovani. The role of Phlebotomus (Euphlebotomus) argentipes as a primary vector for L. donovani highlights the need of accurately identifying and monitoring sand fly species in order to create efficient disease management methods. This study used both morphological and molecular techniques to examine the genetic diversity of Phlebotomine sand flies across Nepal, supporting the national VL elimination program a critical public health initiative given the disease's fatality rate, which is over 95% in untreated cases. This study assessed the DNA barcoding method's utility for identifying and measuring genetic diversity within and among Phlebotomus species collected in Nepal. A total of 315 sand fly specimens from six districts in Nepal were analyzed, together with available data from BOLD and GenBank. The identification success rate using DNA barcoding was 97%, with interspecific genetic divergence ranging from 12.23% (S. babu and S. punjabensis) to 23.45% (P. argentipes and Sergentomyia sp1). For the genus Phlebotomus , including the vector species, the overall divergence averaged 14.89%. The lowest intraspecific genetic divergence was observed in P. transcaucasicus (0.08%), and the highest in P. major (5.85%). The results confirm that the COI barcoding method is an effective tool for identifying sand fly species in Nepal, providing critical data for disease control initiatives and enhancing global understanding of vector-borne diseases
Technical Expertise Report ref. Exp-66, 23/1/2015 - Applicant: Veldeman Structure Solution, Industrieterrein Vostert 1220, 3960 Bree, 31/10/2014
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A phlogopite-bearing lithospheric mantle source for Europe s largest REE-HFSE belt: Gardar Rift, SW Greenland.
No full textAlkaline-silicate complexes host some of the world s largest resources of rare-earth elements and high-field strength elements (REE & HFSE) and represent the most fractionated magmatic systems on our planet. Geochemical evidence indicates that they are mantle melts, but while various studies highlight a role for lithospheric mantle, we do not know the precise origin of their contained REE and HFSE, and whether enrichment of the mantle source for these magmas can be attributed to specific geodynamic processes or events. We present new Nd-Hf isotope measurements (143Nd/144Nd & 176Hf/177Hf ) made by LA-MC-ICP-MS, as well as a compilation of existing isotopic data for a suite of alkaline igneous rocks from the Gardar Province, a Mesoproterozoic continental rift in southern Greenland. Neodymium and hafnium isotopes are unaffected by crystal fractionation and can directly fingerprint the source of REE and HFSE. The dataset covers both phases of Gardar magmatism (1325 1261 and 1184 1140 Ma) and incorporates mafic dyke swarms and km-scale intrusive complexes, including Ilimmaasaq (Ilímaussaq) and Motzfeldt, which host some of the world s largest REE and HFSE deposits. The majority of Gardar complexes have a narrow range of positive median initial εNd (0 to +3.3) and εHf values (+0.2 to+6.0). Only two granite intrusions and the Eriksfjord basaltic lavas have crustally contaminated Nd-Hf isotope compositions, with the vast majority of Gardar igneous rocks preserving the isotope signature of their mantle source. Considering the diversity of rock types in the Gardar Province, initial εNd - εHf compositions are remarkably homogeneous, indicating a derivation of the Gardar s REE and HFSE from a laterally-extensive mantle melt source. Several Gardar systems have low initial εHf for a given εNd (ΔεHf to -9.7), a distinctive signature as few geological processes decouple the Nd and Hf isotope systems. The decoupled Nd-Hf isotope signatures are consistent with contributions from isotopically-matured phlogopite-bearing metasomatic veins (commonly known as PIC: phlogopite-ilmenite-clinopyroxene) in the lithospheric mantle. The metasomatising fluids that formed these source rocks were introduced via Palaeoproterozoic subduction, but the Gardar isotopic signatures indicate that REE and HFSE enrichment of these metasomes was not derived from subducted sediment; instead it is likely that metals were scavenged from the mantle wedge overlying the ancient subduction zone. The Gardar Nd-Hf isotope evolution trends overlap with a global compilation of kimberlites through time and allow us to tie the origin of the PIC metasomes to the regional geodynamic history of South Greenland. We identify PIC metasomes as a key metal source for the Gardar and by extension perhaps other REE-mineralised igneous provinces globally
Local infrasound monitoring of lava eruptions at Nyiragongo volcano (D.R. Congo) using urban and near-source stations
No full textDuring eruptions, volcanoes produce air-pressure waves inaudible for the human ear called infrasound, which are very helpful for detecting early signs of magma at the surface. Compared to violent ash-rich explosions, recording more discrete atmospheric disturbances from effusive eruptions remains a practical challenge depending on the distance to the source. At Nyiragongo volcano (D.R. Congo), towering above a 1-million urban area, we analyzed local infrasonic records between January 2018 and April 2022. An acoustic signature from this open-vent volcano is detected up to the volcano observatory facilities in Goma city center about 17 km from its crater. We compared infrasound signals with space-based observations of the intra-crater activity (SO2 emissions, thermal anomalies, crater depth/radius). We thus obtain a comprehensive picture of Nyiragongo's eruptive activity during this period, encompassing the drainage of its lava lake during its third known flank eruption on 22 May 2021