Causal deep learning reveals the comparative effectiveness of antihyperglycemic treatments in poorly controlled diabetes.

Type-2 diabetes is associated with severe health outcomes, the effects of which are responsible for approximately 1/4 of the total healthcare spending in the United States (US). Current treatment guidelines endorse a massive number of potential anti-hyperglycemic treatment options in various combinations. Strategies for optimizing treatment selection are lacking.

Minimizing bias in massive multi-arm observational studies with BCAUS: balancing covariates automatically using supervision.

Background: Observational studies are increasingly being used to provide supplementary evidence in addition to Randomized Control Trials (RCTs) because they provide a scale and diversity of participants and outcomes that would be infeasible in an RCT. Additionally, they more closely reflect the settings in which the studied interventions will be applied in the future. Well-established propensity-score-based methods exist to overcome the challenges of working with observational data to estimate causal effects.

Applications, promises, and pitfalls of deep learning for fluorescence image reconstruction.

Deep learning is becoming an increasingly important tool for image reconstruction in fluorescence microscopy. We review state-of-the-art applications such as image restoration and super-resolution imaging, and discuss how the latest deep learning research could be applied to other image reconstruction tasks. Despite its successes, deep learning also poses substantial challenges and has limits.

Geometric phase magnetometry using a solid-state spin.

A key challenge of magnetometry lies in the simultaneous optimization of magnetic field sensitivity and maximum field range. In interferometry-based magnetometry, a quantum two-level system acquires a dynamic phase in response to an applied magnetic field. However, due to the 2π periodicity of the phase, increasing the coherent interrogation time to improve sensitivity reduces field range.

Fourier magnetic imaging with nanoscale resolution and compressed sensing speed-up using electronic spins in diamond.

Optically detected magnetic resonance using nitrogen-vacancy (NV) colour centres in diamond is a leading modality for nanoscale magnetic field imaging, as it provides single electron spin sensitivity, three-dimensional resolution better than 1 nm (ref. 5) and applicability to a wide range of physical and biological samples under ambient conditions. To date, however, NV-diamond magnetic imaging has been performed using 'real-space' techniques, which are either limited by optical diffraction to ∼250 nm resolution or require slow, point-by-point scanning for nanoscale resolution, for example, using an atomic force microscope, magnetic tip, or super-resolution optical imaging.

Nanoscale NMR spectroscopy and imaging of multiple nuclear species.

Nuclear magnetic resonance (NMR) spectroscopy and magnetic resonance imaging (MRI) provide non-invasive information about multiple nuclear species in bulk matter, with wide-ranging applications from basic physics and chemistry to biomedical imaging. However, the spatial resolution of conventional NMR and MRI is limited to several micrometres even at large magnetic fields (>1 T), which is inadequate for many frontier scientific applications such as single-molecule NMR spectroscopy and in vivo MRI of individual biological cells. A promising approach for nanoscale NMR and MRI exploits optical measurements of nitrogen-vacancy (NV) colour centres in diamond, which provide a combination of magnetic field sensitivity and nanoscale spatial resolution unmatched by any existing technology, while operating under ambient conditions in a robust, solid-state system.

Dressed-state resonant coupling between bright and dark spins in diamond.

Under ambient conditions, spin impurities in solid-state systems are found in thermally mixed states and are optically "dark"; i.e., the spin states cannot be optically controlled.

Suppression of spin-bath dynamics for improved coherence of multi-spin-qubit systems.

Multi-qubit systems are crucial for the advancement and application of quantum science. Such systems require maintaining long coherence times while increasing the number of qubits available for coherent manipulation. For solid-state spin systems, qubit coherence is closely related to fundamental questions of many-body spin dynamics.

Hiding single photons with spread spectrum technology.

We describe a proof-of-principal experiment demonstrating the use of spread spectrum technology at the single photon level. We show how single photons with a prescribed temporal shape, in the presence of interfering noise, may be hidden and recovered.

Electro-optic modulation of single photons.

We use the Stokes photon of a biphoton pair to set the time origin for electro-optic modulation of the wave function of the anti-Stokes photon thereby allowing arbitrary phase and amplitude modulation. We demonstrate conditional single-photon wave functions composed of several pulses, or instead, having Gaussian or exponential shapes.

Observation of optical precursors at the biphoton level.

We describe the observation of a sharp leading-edge spike in a biphoton wave packet that is produced using slow light and measured by two-photon correlation. Using the stationary-phase approximation we characterize this spike as a Sommerfeld-Brillouin precursor resulting from the interference of low- and high-frequency spectral components.

Subnatural linewidth biphotons with controllable temporal length.

This Letter describes the generation of biphotons with a temporal length that can be varied over the range of 50-900 ns, with an estimated subnatural linewidth as small as 0.75 MHz. We make use of electromagnetically induced transparency and slow light in a two-dimensional magneto-optical trap with an optical depth as high as 62.

Generation of narrow-bandwidth paired photons: use of a single driving laser.

We describe a generator of narrow-band paired photons. A single retroreflected Ti:sapphire laser is used to cool, render transparent, and parametrically pump a cloud of (87)Rb atoms. We attain a paired-photon generation rate into opposing fibers of 600 counts/s with an intensity correlation function that has a width of 5 ns, and violates the Cauchy-Schwartz criteria by a factor of 2000.