All Polarization-maintaining Er-doped Fiber Laser Modelocked by a Graphene Saturable Absorber Employing an Intra-cavity Compressor for Dispersion Management

The performance of a stable dispersion tunable Erbium doped fiber laser modelocked by multi-layer graphene is presented and discussed. The cavity is based on all PM fibers and a free-space Martinez compressor.QC 20180110</p

Multi-layer graphene mode-locked Er-doped fiber laser as a test bed fortargeting specific operating regimes

We present an all polarization maintaining Er-doped fiber laser mode-locked by multi-layer graphene providing tunable dispersion through an intra-cavity compressor. Experimental output characteristics, when using a saturable absorber able to support three different operating regimes, are presented which show the utility of our source as a test bed for laser design.QC 20180926</p

All Polarization-maintaining Er-doped Fiber Laser Modelocked by a Graphene Saturable Absorber Employing an Intra-cavity Compressor for Dispersion Management

The performance of a stable dispersion tunable Erbium doped fiber laser modelocked by multi-layer graphene is presented and discussed. The cavity is based on all PM fibers and a free-space Martinez compressor.QC 20180110</p

Multi-layer graphene mode-locked Er-doped fiber laser as a test bed fortargeting specific operating regimes

We present an all polarization maintaining Er-doped fiber laser mode-locked by multi-layer graphene providing tunable dispersion through an intra-cavity compressor. Experimental output characteristics, when using a saturable absorber able to support three different operating regimes, are presented which show the utility of our source as a test bed for laser design.QC 20180926</p

Multi-layer graphene mode-locked Er-doped fiber laser as a test bed fortargeting specific operating regimes

We present an all polarization maintaining Er-doped fiber laser mode-locked by multi-layer graphene providing tunable dispersion through an intra-cavity compressor. Experimental output characteristics, when using a saturable absorber able to support three different operating regimes, are presented which show the utility of our source as a test bed for laser design.QC 20180926</p

Noninvasive two-photon optical biopsy of retinal fluorophores

High-resolution imaging techniques capable of detecting identifiable endogenous fluorophores in the eye along with genetic testing will dramatically improve diagnostic capabilities in the ophthalmology clinic and accelerate the development of new treatments for blinding diseases. Two-photon excitation (TPE)-based imaging overcomes the filtering of ultraviolet light by the lens of the human eye and thus can be utilized to discover defects in vitamin A metabolism during the regeneration of the visual pigments required for the detection of light. Combining TPE with fluorescence lifetime imaging (FLIM) and spectral analyses offers the potential of detecting diseases of the retina at earlier stages before irreversible structural damage has occurred. The main barriers to realizing the benefits of TPE for imaging the human retina arise from concerns about the high light exposure typically needed for informative TPE imaging and the requirement to correlate the ensuing data with different states of health and disease. To overcome these hurdles, we improved TPE efficiency by controlling temporal properties of the excitation light and employed phasor analyses to FLIM and spectral data in mouse models of retinal diseases. Modeling of retinal photodamage revealed that plasma-mediated effects do not play a role and that melanin-related thermal effects are mitigated by reducing pulse repetition frequency. By using noninvasive TPE imaging we identified molecular components of individual granules in the retinal pigment epithelium and present their analytical characteristics

In vivo imaging of the human eye using a 2-photon-excited fluorescence scanning laser ophthalmoscope

International audienc

The influenza-injured lung microenvironment promotes MRSA virulence, contributing to severe secondary bacterial pneumonia

Influenza infection is substantially worsened by the onset of secondary pneumonia caused by bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA). The bidirectional interaction between the influenza-injured lung microenvironment and MRSA is poorly understood. By conditioning MRSA ex vivo in bronchoalveolar lavage fluid collected from mice at various time points of influenza infection, we found that the influenza-injured lung microenvironment dynamically induces MRSA to increase cytotoxin expression while decreasing metabolic pathways. LukAB, a SaeRS two-component system-dependent cytotoxin, is particularly important to the severity of post-influenza MRSA pneumonia. LukAB’s activity is likely shaped by the post-influenza lung microenvironment, as LukAB binds to (and is activated by) heparan sulfate (HS) oligosaccharide sequences shed from the epithelial glycocalyx after influenza. Our findings indicate that post-influenza MRSA pneumonia is shaped by bidirectional host-pathogen interactions: host injury triggers changes in bacterial expression of toxins, the activity of which may be shaped by host-derived HS fragments