Reflectance mapping with microsphere-assisted white light interference nanoscopy.

The characterisation of novel materials presents a challenge that requires new and original developments. To face some of these demands for making measurements at the nanoscale, a new microsphere-assisted white light interference nanoscope performing local reflectance mapping is presented. This technique presents the advantages of being non-destructive, full-field and label-free.

Impact sensitivities of energetic materials derived from easy-to-compute rate constants.

New procedures to estimate the impact sensitivity of energetic materials are derived from an earlier semiempirical model correlating the drop weight impact height to the rate constant for the propagation of the decomposition process, assumed to be the limiting step. The new models are obtained by removing step by step the empiricism in the evaluation of . We end up with a full expression for this constant in terms of theoretical activation energies and prefactors.

Detection of acute promyelocytic leukemia in peripheral blood and bone marrow with annotation-free deep learning.

While optical microscopy inspection of blood films and bone marrow aspirates by a hematologist is a crucial step in establishing diagnosis of acute leukemia, especially in low-resource settings where other diagnostic modalities are not available, the task remains time-consuming and prone to human inconsistencies. This has an impact especially in cases of Acute Promyelocytic Leukemia (APL) that require urgent treatment. Integration of automated computational hematopathology into clinical workflows can improve the throughput of these services and reduce cognitive human error.

Content aware multi-focus image fusion for high-magnification blood film microscopy.

Automated digital high-magnification optical microscopy is key to accelerating biology research and improving pathology clinical pathways. High magnification objectives with large numerical apertures are usually preferred to resolve the fine structural details of biological samples, but they have a very limited depth-of-field. Depending on the thickness of the sample, analysis of specimens typically requires the acquisition of multiple images at different focal planes for each field-of-view, followed by the fusion of these planes into an extended depth-of-field image.

Optical mesoscopy, machine learning, and computational microscopy enable high information content diagnostic imaging of blood films.

Automated image-based assessment of blood films has tremendous potential to support clinical haematology within overstretched healthcare systems. To achieve this, efficient and reliable digital capture of the rich diagnostic information contained within a blood film is a critical first step. However, this is often challenging, and in many cases entirely unfeasible, with the microscopes typically used in haematology due to the fundamental trade-off between magnification and spatial resolution.

Wide-field parallel mapping of local spectral and topographic information with white light interference microscopy.

Fourier analysis of interferograms captured in white light interference microscopy is proposed for performing simultaneous local spectral and topographic measurements at high spatial resolution over a large field of view. The technique provides a wealth of key information on local sample properties. We describe the processing and calibration steps involved to produce reflectivity maps of spatially extended samples.

Structure-dependent amplification for denoising and background correction in Fourier ptychographic microscopy.

Fourier Ptychographic Microscopy (FPM) allows high resolution imaging using iterative phase retrieval to recover an estimate of the complex object from a series of images captured under oblique illumination. FPM is particularly sensitive to noise and uncorrected background signals as it relies on combining information from brightfield and noisy darkfield (DF) images. In this article we consider the impact of different noise sources in FPM and show that inadequate removal of the DF background signal and associated noise are the predominant cause of artefacts in reconstructed images.

Synthesis and Characterization of 5-MeO-DMT Succinate for Clinical Use.

To support clinical use, a multigram-scale process has been developed to provide 5-MeO-DMT, a psychedelic natural product found in the parotid gland secretions of the toad, . Several synthetic routes were initially explored, and the selected process featured an optimized Fischer indole reaction to 5-MeO-DMT freebase in high-yield, from which the 1:1 succinate salt was produced to provide 136 g of crystalline active pharmaceutical ingredient (API) with 99.86% peak area by high-performance liquid chromatography (HPLC) and a net yield of 49%.

Data-driven malaria prevalence prediction in large densely populated urban holoendemic sub-Saharan West Africa.

Over 200 million malaria cases globally lead to half-million deaths annually. The development of malaria prevalence prediction systems to support malaria care pathways has been hindered by lack of data, a tendency towards universal "monolithic" models (one-size-fits-all-regions) and a focus on long lead time predictions. Current systems do not provide short-term local predictions at an accuracy suitable for deployment in clinical practice.

Expert-level automated malaria diagnosis on routine blood films with deep neural networks.

Over 200 million malaria cases globally lead to half a million deaths annually. Accurate malaria diagnosis remains a challenge. Automated imaging processing approaches to analyze Thick Blood Films (TBF) could provide scalable solutions, for urban healthcare providers in the holoendemic malaria sub-Saharan region.

Digital refocusing and extended depth of field reconstruction in Fourier ptychographic microscopy.

Fourier ptychography microscopy (FPM) is a recently developed microscopic imaging method that allows the recovery of a high-resolution complex image by combining a sequence of bright and darkfield images acquired under inclined illumination. The capacity of FPM for high resolution imaging at low magnification makes it particularly attractive for applications in digital pathology which require imaging of large specimens such as tissue sections and blood films. To date most applications of FPM have been limited to imaging thin samples, simplifying both image reconstruction and analysis.

Coherence scanning interferometry allows accurate characterization of micrometric spherical particles contained in complex media.

Characterizing very small particles, from a few dozen micrometers to the nanometric scale, is a very challenging application in a wide range of domains. In this work, we demonstrate, through the recovery of silica and polystyrene bead properties (i.e.

Synthesis of α-alkylated γ-butyrolactones with concomitant anhydride kinetic resolution using a sulfamide-based catalyst.

The Kinetic Resolution (KR) of α-alkylated enolisable disubstituted anhydrides has been shown to be possible for the first time. In the presence of an ad hoc designed novel class of bifunctional sulfamide organocatalyst, a regio-, diastereo- and enantioselective cycloaddition reaction between the enolisable anhydride and benzaldehydes provides densely functionalised γ-butyrolactones in one pot (up to 19 : 1 dr, 94% ee) with control over three contiguous stereocentres. The concomitant resolution of the starting material anhydride, provides access to a range of chiral succinate derivatives with selectivity factors up to S* = 10.

Dynamic kinetic resolution of bis-aryl succinic anhydrides: enantioselective synthesis of densely functionalised γ-butyrolactones.

The efficient Dynamic Kinetic Resolution (DKR) of disubstituted anhydrides has been shown to be possible for the first time. Using an ad hoc designed organocatalyst and an enantio- and diastereoselective cycloaddition process with aldehydes, stereochemically complex γ-butyrolactone derivatives can be obtained - with control over three contiguous stereocentres, one of which is all carbon quaternary.

Depth-resolved local reflectance spectra measurements in full-field optical coherence tomography.

Full-field optical coherence tomography (FF-OCT) is a widely used technique for applications such as biological imaging, optical metrology, and materials characterization, providing structural and spectral information. By spectral analysis of the backscattered light, the technique of spectroscopic-OCT enables the differentiation of structures having different spectral properties, but not the determination of their reflectance spectrum. For surface measurements, this can be achieved by applying a Fourier transform to the interferometric signals and using an accurate calibration of the optical system.

All-optical nonlinear processing of both polarization state and intensity profile for 40 Gbit/s regeneration applications.

In this paper, we report all-optical regeneration of the state of polarization of a 40-Gbit/s return-to-zero telecommunication signal as well as its temporal intensity profile and average power thanks to an easy-to-implement, all-fibered device. In particular, we experimentally demonstrate that it is possible to obtain simultaneously polarization stabilization and intensity profile regeneration of a degraded light beam thanks to the combined effects of counterpropagating four-wave mixing, self-phase modulation and normal chromatic dispersion taking place in a single segment of optical fiber. All-optical regeneration is confirmed by means of polarization and bit-error-rate measurements as well as real-time observation of the 40 Gbit/s telecommunication signal.

Mycoplasmosis in evening and pine grosbeaks with conjunctivitis in Quebec.

An outbreak of conjunctivitis affected evening grosbeaks (Coccothraustes vespertinus) and pine grosbeaks (Pinicola enucleator) in Quebec (Canada) during the winter 1998-99. One to 30% of the individuals from these two species were sick at 13 feeding stations. Sick birds were thin and had unilateral or bilateral catarrhal and lymphoplasmacytic conjunctivitis and rhinitis, and mucopurulent infra-orbital sinusitis.

Bronchopneumonia caused by Streptococcus equi in a North Atlantic pilot whale (Globicephala melaena).

Bronchopneumonia was observed at the necropsy of a North Atlantic pilot whale (Globicephala melaena). The areas of necrosis were well circumscribed clusters, disseminated throughout the left lung. Streptococcus equi was isolated in pure culture from the lung parenchyma, pharynx and pericardial fluid.