25 research outputs found
Measurement of the very rare decay
The decay K+→π+νν¯
, with a very precisely predicted branching ratio of less than 10−10
,
is among the best processes to reveal indirect effects of new physics.
The NA62 experiment at CERN SPS is designed to study the K+→π+νν¯
decay and to measure its branching ratio using a decay-in-flight technique.
NA62 took data in 2016, 2017 and 2018, reaching the sensitivity of the Standard Model
for the K+→π+νν¯
decay by the analysis of the 2016 and 2017 data,
and providing the most precise measurement of the branching ratio to date
by the analysis of the 2018 data.
This measurement is also used to set limits on BR(K+→π+X
), where X
is a scalar
or pseudo-scalar particle.
The final result of the BR(K+→π+νν¯
) measurement and its interpretation in terms
of the K+→π+X
decay from the analysis of the full 2016-2018 data set is presented, and future plans and prospects are reviewed
Water-soluble carbonyl complexes of 99Tc(I) and Re(I) with adamantane-cage aminophosphines PTA and CAP
Pentacarbonyl complexes of 99Tc and Re [M(CAP)(CO)5]X and [M(PTA)(CO)5]X (M = 99Tc or Re and X = ClO4− or OTf–) with aminophosphine ligands 1,4,7-triaza-9-phosphatricyclo[5.3.214,9]tridecane (CAP) and 1,3,5-triaza-7-phosphaadamantane (PTA) were prepared for the first time by the reaction of [MX(CO)5] (M = 99Tc or Re, X = ClO4− or OTf–) with CAP and PTA in CH2Cl2 at room temperature. The reaction of [TcCl(CO)5] with CAP in refluxing CH2Cl2 yields the tricarbonyl complex [99TcCl(CAP)2(CO)3]. Treatment of [Re(H2O)3(CO)3]Cl with CAP in aqueous solution at 40–50 °C gives the rhenium analog [ReCl(CAP)2(CO)3]. Both penta- and tricarbonyl phosphine complexes were characterized by spectroscopic methods (IR, NMR, MS) and single crystal X-ray diffraction. The [M(PTA)(CO)5]X complexes are soluble in aqueous solutions, whereas their CAP analogs are not. The CAP complexes become water-soluble after acidification with dilute acids. As the pH of their aqueous solutions increases, they start to slowly degrade at pH 8 and completely decompose at pH 14. In acidic media, the pentacarbonyl complexes undergo stepwise protonation and are stable indefinitely
Technetium-99m and rhenium tricarboyl 2+1 complexes as potential myocardial perfusion agents
Synthesis, characterization and pre‐clinical evaluation of 99mTc‐tricarbonyl complexes as potential myocardial perfusion imaging agents
How do vascular plants perform photosynthesis in extreme environments? An integrative ecophysiological and biochemical story
In this work, we review the physiological and molecular mechanisms that allow vascular plants to perform photosynthesis in extreme environments, such as deserts, polar and alpine ecosystems. Specifically, we discuss the morpho/anatomical, photochemical and metabolic adaptive processes that enable a positive carbon balance in photosynthetic tissues under extreme temperatures and/or severe water-limiting conditions in C3 species. Nevertheless, only a few studies have described the in situ functioning of photoprotection in plants from extreme environments, given the intrinsic difficulties of fieldwork in remote places. However, they cover a substantial geographical and functional range, which allowed us to describe some general trends. In general, photoprotection relies on the same mechanisms as those operating in the remaining plant species, ranging from enhanced morphological photoprotection to increased scavenging of oxidative products such as reactive oxygen species. Much less information is available about the main physiological and biochemical drivers of photosynthesis: stomatal conductance (gs), mesophyll conductance (gm) and carbon fixation, mostly driven by RuBisCO carboxylation. Extreme environments shape adaptations in structures, such as cell wall and membrane composition, the concentration and activation state of Calvin–Benson cycle enzymes, and RuBisCO evolution, optimizing kinetic traits to ensure functionality. Altogether, these species display a combination of rearrangements, from the whole-plant level to the molecular scale, to sustain a positive carbon balance in some of the most hostile environments on Earth.Fil: Fernández Marín, Beatriz. Universidad de La Laguna; EspañaFil: Gulías, Javier. Institut D´investigacion Sanitaria Llles Balears (idlsba);Fil: Figueroa, Carlos Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Iñiguez, Concepción. Institut D´investigacion Sanitaria Llles Balears (idlsba);Fil: Clemente Moreno, María J.. Institut D´investigacion Sanitaria Llles Balears (idlsba);Fil: Nunes Nesi, Adriano. Universidade Federal de Viçosa.; BrasilFil: Fernie, Alisdair R.. Max Planck Institute Of Molecular Plant Physiology; AlemaniaFil: Cavieres, Lohengrin A.. Universidad de Concepción; ChileFil: Bravo, León A.. Universidad de La Frontera; ChileFil: García Plazaola, José I.. Universidad del País Vasco; EspañaFil: Gago, Jorge. Institut D´investigacion Sanitaria Llles Balears (idlsba)
Tris(methyltrihydroborato)(tetrahydrofuran)ytterbium(III) complex: structure and volatility
CCDC 956662: Experimental Crystal Structure Determination
Related Article: Beverley L. Ellis, Nikolay I. Gorshkov, Alexander A. Lumpov, Alexander E. Miroslavov, Anatoly N. Yalfimov, Vladislav V. Gurzhiy, Dmitrii N. Suglobov, Rattana Braddock, Joanne C. Adams, Anne-Marie Smith, Mary C. Prescott and Harbans L. Sharma|2013|J.Labelled Comp.Radiopharm.|56|700|doi:10.1002/jlcr.310