Treatment of bone and joint infections by ceftazidime/avibactam and ceftolozane/tazobactam: a cohort study.

Objectives: Ceftazidime/avibactam (C/A) and ceftolozane/tazobactam (C/T) are two novel antibacterials with known efficacy against Gram-negative bacteria (GNB). We aimed to describe the efficacy and safety of surgical management combined with C/A or C/T treatment for bone and joint infections (BJIs).

Methods: We conducted an observational, bicentric study of patients treated with C/A or C/T for a BJI between May 2016 and June 2019.

Bloodstream infections in older population: epidemiology, outcome, and impact of multidrug resistance.

Bloodstream infections (BSIs) among older patients are frequent with high rate of mortality. Infections with multidrug-resistant organisms (MDRO) are associated with higher mortality than with susceptible microorganisms. We aimed to evaluate the prevalence of MDRO infection during BSI in older population and the factors associated with unfavorable outcome.

[Leptospirosis].

Leptospirosis. Leptospirosis is the first worldwide anthropozoonosis with an incidence of 1 000 000 cases per year. It is more frequently encountered in tropical areas but also can be diagnosed in tempered places.

Optical extinction in a single layer of nanorods.

We demonstrate that almost 100% of incident photons can interact with a monolayer of scatterers in a symmetrical environment. Nearly perfect optical extinction through free-standing transparent nanorod arrays has been measured. The sharp spectral opacity window, in the form of a characteristic Fano resonance, arises from the coherent multiple scattering in the array.

Efficient white light emission by upconversion in Yb(3+)-, Er(3+)- and Tm(3+)-doped Y2BaZnO5.

We report efficient white upconversion luminescence in Yb(3+)-, Er(3+)- and Tm(3+)-doped monophasic and biphasic Y(2)BaZnO(5) phosphors under 977 nm near-infrared excitation and at low excitation power densities (down to ∼25 mW mm(-2)).

Impedance of a nanoantenna and a single quantum emitter.

Antennas are widely used by electrical engineers to enhance the coupling between propagating waves and electric sources or detectors. It is thus tempting to develop an optical analog to tailor visible light emission or absorption by an atom or a molecule. This idea has been put forward recently and it has been demonstrated that both the radiative rate and the emission pattern of optical emitters can be modified by metallic nanostructures.

Quantum thermal bath for molecular dynamics simulation.

Molecular dynamics (MD) is a numerical simulation technique based on classical mechanics. It has been taken for granted that its use is limited to a large temperature regime where classical statistics is valid. To overcome this limitation, the authors introduce in a universal way a quantum thermal bath that accounts for quantum statistics while using standard MD.

Scattering forces from the curl of the spin angular momentum of a light field.

Light forces on small (Rayleigh) particles are usually described as the sum of two terms: the dipolar or gradient force and the scattering or radiation pressure force. The scattering force is traditionally considered proportional to the Poynting vector, which gives the direction and magnitude of the momentum flow. However, as we will show, there is an additional nonconservative contribution to the scattering force arising in a light field with nonuniform helicity.

Optical resonances in one-dimensional dielectric nanorod arrays: field-induced fluorescence enhancement.

Arrays of transparent dielectric nanorods are shown to produce very large local field enhancements at specific resonant conditions. These structures would lead to enhancement of molecular fluorescence signals without quenching. The resonant angular width and field enhancements are analytically derived as a function of wavelength, grating period, rod radius, and dielectric constant.

Extraordinary optical reflection from sub-wavelength cylinder arrays.

A multiple scattering analysis of the reflectance of a periodic array of sub-wavelength cylinders is presented. The optical properties and their dependence on wavelength, geometrical parameters and cylinder dielectric constant are analytically derived for both s- and p-polarized waves. In absence of Mie resonances and surface (plasmon) modes, and for positive cylinder polarizabilities, the reflectance presents sharp peaks close to the onset of new diffraction modes (Rayleigh frequencies).