387 research outputs found
Animal welfare in brown trout farming: hematological results
The effect of stress resulting from fish farming has received considerable attention in this last period and fish welfare in aquaculture is a relevant topic, very important for the future of aquaculture (Watson et al., 2004; Klinger et al., 1996; Peres et al., 2004; Ron et al., 1995;Wagner et al., 1995;Watson et al., 1998). Brown trout farming is less developed then rainbow trout farming, but this kind of fish farming is increasing, mainly for fish conservation and restocking aquaculture
Lock Per CVC: realtà e nuove prospettive
Il lock dei CVC rappresenta una tematica estremamente attuale, in particolare nel campo degli accessi vascolari per dialisi. Le recenti conoscenze sul biofilm hanno spostato l'interesse dalla proprietà del lock di garantire la pervietà del CVC a quella di prevenire le infezioni. Tuttavia non abbiamo ancora a disposizione un lock ideale dotato di proprietà antitrombotiche e protettive nei confronti delle infezioni. L'eparina rappresenta il lock tradizionalmente più utilizzato anche se nel corso del tempo ha mostrato alcuni aspetti sfavorevoli e stimolato la ricerca di soluzioni alternative. Tra queste l'uso dei chelanti, in particolare del citrato di sodio a bassa concentrazione (3.8–4%) è quella che riscuote attualmente il maggiore consenso per la sicurezza di impiego e i costi ridotti. Citrato ad alta concentrazione (46.7%), taurolidina ed etanolo rappresentano invece lock avanzati, ciascuno con peculiari caratteristiche e prospettive di futuro impiego. In ogni caso l'aderenza alle misure di prevenzione generali nei confronti delle infezioni e la corretta gestione del CVC costituiscono la condizione imprescindibile per l'attività quotidiana indipendentemente dalla scelta del lock
Direct experimental observation of nonclassicality in ensembles of single photon emitters
In this work we experimentally demonstrate for the first time a recently
proposed criterion adressed to detect nonclassical behavior in the fluorescence
emission of ensembles of single-photon emitters. In particular, we apply the
method to study clusters of NV centres in diamond observed via
single-photon-sensitive confocal microscopy. Theoretical considerations on the
behavior of the parameter at any arbitrary order in presence of poissonian
noise are presented and, finally, the opportunity of detecting manifold
coincidences is discussed
Native NIR-emitting single colour centres in CVD diamond
Single-photon sources are a fundamental element for developing quantum
technologies, and sources based on colour centres in diamonds are among the
most promising candidates. The well-known NV centres are characterized by
several limitations, thus few other defects have recently been considered. In
the present work, we characterize in detail native efficient single colour
centres emitting in the near infra-red in both standard IIa single-crystal and
electronic-grade polycrystalline commercial CVD diamond samples. In the former
case, a high-temperature annealing process in vacuum is necessary to induce the
formation/activation of luminescent centres with good emission properties,
while in the latter case the annealing process has marginal beneficial effects
on the number and performances of native centres in commercially available
samples. Although displaying significant variability in several photo physical
properties (emission wavelength, emission rate instabilities, saturation
behaviours), these centres generally display appealing photophysical properties
for applications as single photon sources: short lifetimes, high emission rates
and strongly polarized light. The native centres are tentatively attributed to
impurities incorporated in the diamond crystal during the CVD growth of
high-quality type IIa samples, and offer promising perspectives in
diamond-based photonics.Comment: 27 pages, 10 figures. Submitted to "New Journal of Phsyics",
NJP-100003.R
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