An optoelectronic implantable neurostimulation platform allowing full MRI safety and optical sensing and communication.

A novel programmable implantable neurostimulation platform based on photonic power transfer has been developed for various clinical applications with the main focus of being safe to use with MRI scanners. The wires usually conveying electrical current from the neurostimulator to the electrodes are replaced by optical fibers. Photovoltaic cells at the tip of the fibers convert laser light to biphasic electrical impulses together with feedback signals with 54% efficiency. Furthermore, a biocompatible, implantable and ultra-flexible optical lead was developed including custom optical fibers. The neurostimulator platform incorporates advanced signal processing and optical physiological sensing capabilities thanks to a hermetically sealed transparent nonmetallic casing. Skin transparency also allowed the development of a high-speed optical transcutaneous communication channel. This implantable neurostimulation platform was first adapted to a vagus nerve stimulator for the treatment of epilepsy. This neurostimulator has been designed to fulfill the requirements of a class III long-term implantable medical device. It has been proven compliant with standard ISO/TS10974 for 1.5 T and 3 T MRI scanners. The device poses no related threat and patients can safely undergo MRI without specific or additional precautions. Especially, the RF induced heating near the implant remains below 2 °C whatever the MRI settings used. The main features of this unique advanced neurostimulator and its architecture are presented. Its functional performance is evaluated, and results are described with a focus on optoelectronics aspects and MRI safety.

Measurement-based care training curriculum in psychiatry residency programs: I: Description of the curriculum and demonstration of implementation.

BACKGROUND: Recent literature shows that most practicing psychiatrists do not receive training in measurement-based care (MBC). Among the primary barriers to MBC implementation are the lack of formal training and curriculums. We present the first comprehensive MBC curriculum for use in adult psychiatric practice, and describe how the curriculum is adapted and implemented in psychiatry residency training programs. METHODS: The Standard for Clinicians' Interview in Psychiatry (SCIP) was developed as a measurement-based care tool for clinicians' use. The SCIP is the only instrument that includes 18 reliable and validated clinician-rated scales covering most adult psychiatric disorders. The SCIP has simple, unified rules of measurement that apply to the 18 scales. The MBC curriculum includes 2 instruction manuals, 4 didactic lectures, and 12 videotaped interviews. We describe the annual learning and implementation of MBC curriculum in residency programs. RESULTS: The curriculum implementation at West Virginia University and Delaware Psychiatric Center began in 2019 and is ongoing. We present 3 case demonstrations of the implementation of MBC in clinical settings. CONCLUSIONS: Comprehensive implementation of MBC curriculum in residency programs has the potential to facilitate research and create a "culture" of MBC in future generations of psychiatrists.

Measurement-based Care in Psychiatry-Past, Present, and Future.

The authors define measurement-based care (MBC) in psychiatry as the use of validated clinical measurement instruments to objectify the assessment, treatment, and clinical outcomes, including efficacy, safety, tolerability, functioning, and quality of life, in patients with psychiatric disorders. MBC includes two processes: routine assessments, such as measuring the severity of symptoms with rating scales, and the use of assessments in decision-making. MBC implementation was tested in the Texas Medication Algorithm Project and the German Algorithm Project and has been shown to improve patient outcomes. Even though more recent research has shown the many benefits of MBC compared to the usual care, MBC is still not the standard of care in psychiatric practice. This review article addresses the advantages of MBC, the barriers to implementing MBC in clinical practice, and the basic properties of MBC instruments. Recent developments in the 21st century that are expected to accelerate the adoption of MBC in clinical practice, including electronic health records, health information technology, and the development of the Standard for Clinicians' lnterview in Psychiatry (SCIP) as an MBC tool, will be reviewed. The authors recommend including MBC in psychiatry residency training to promote its use in future generations.

Study of high order plasmonic modes on ceramic nanodisks.

Transition metal nitrides are promising alternative plasmonic materials to noble metals for data storage applications as they exhibit localized surface plasmon resonances and have high melting temperatures. Here, angle dependent spectral measurements of the plasmonic resonances of nanodisk arrays made from titanium nitride are examined. Polarized light is used to excite the quadrupole and higher order resonance plasmonic modes which are required in the state-of-the-art designs of near-field transducers used in plasmonic enhanced magnetic recording. Numerical simulations compare the energy distribution and absorption efficiencies for different sized Au and Ti nanodisks. A high electric field enhancement is calculated at the termination of a lollipop plasmonic transducer made of titanium nitride which is shifted to longer wavelengths when compared with an Au transducer of the same dimensions. This, together with its outstanding material properties makes TiN a favourable material for data storage applications.

Lithographically Defined, Room Temperature Low Threshold Subwavelength Red-Emitting Hybrid Plasmonic Lasers.

Hybrid plasmonic lasers provide deep subwavelength optical confinement, strongly enhanced light-matter interaction and together with nanoscale footprint promise new applications in optical communication, biosensing, and photolithography. The subwavelength hybrid plasmonic lasers reported so far often use bottom-up grown nanowires, nanorods, and nanosquares, making it difficult to integrate these devices into industry-relevant high density plasmonic circuits. Here, we report the first experimental demonstration of AlGaInP based, red-emitting hybrid plasmonic lasers at room temperature using lithography based fabrication processes. Resonant cavities with deep subwavelength 2D and 3D mode confinement of λ2/56 and λ3/199, respectively, are demonstrated. A range of cavity geometries (waveguides, rings, squares, and disks) show very low lasing thresholds of 0.6-1.8 mJ/cm2 with wide gain bandwidth (610 nm-685 nm), which are attributed to the heterogeneous geometry of the gain material, the optimized etching technique, and the strong overlap of the gain material with the plasmonic modes. Most importantly, we establish the connection between mode confinements and enhanced absorption and stimulated emission, which plays critical roles in maintaining low lasing thresholds at extremely small hybrid plasmonic cavities. Our results pave the way for the further integration of dense arrays of hybrid plasmonic lasers with optical and electronic technology platforms.

Integrated plasmonic circuitry on a vertical-cavity surface-emitting semiconductor laser platform.

Integrated plasmonic sources and detectors are imperative in the practical development of plasmonic circuitry for bio- and chemical sensing, nanoscale optical information processing, as well as transducers for high-density optical data storage. Here we show that vertical-cavity surface-emitting lasers (VCSELs) can be employed as an on-chip, electrically pumped source or detector of plasmonic signals, when operated in forward or reverse bias, respectively. To this end, we experimentally demonstrate surface plasmon polariton excitation, waveguiding, frequency conversion and detection on a VCSEL-based plasmonic platform. The coupling efficiency of the VCSEL emission to waveguided surface plasmon polariton modes has been optimized using asymmetric plasmonic nanostructures. The plasmonic VCSEL platform validated here is a viable solution for practical realizations of plasmonic functionalities for various applications, such as those requiring sub-wavelength field confinement, refractive index sensitivity or optical near-field transduction with electrically driven sources, thus enabling the realization of on-chip optical communication and lab-on-a-chip devices.

Multi-level single mode 2D polymer waveguide optical interconnects using nano-imprint lithography.

Single and multi-layer passive optical interconnects using single mode polymer waveguides are demonstrated using UV nano-imprint lithography. The fabrication tolerances associated with imprint lithography are investigated and we show a way to experimentally quantify a small variation in index contrast between core and cladding of fabricated devices. 1x2 splitting devices based on directional couplers and multimode interference interferometers are demonstrated to have less than 0.45 dB insertion loss with 0.02 ± 0.01 dB power imbalance between the outputs. We demonstrate an 'optical via' with an insertion loss less than 0.45 dB to transfer light from one optical signal plane to another. A 1x4 two-dimensional optical port is experimentally demonstrated to spatially split the input power with an insertion loss of 1.2 dB.

Dual resonance approach to decoupling surface and bulk attributes in photonic crystal biosensor.

A sub-wavelength grating-based photonic crystal sensor is designed to excite two spectrally and spatially different guided mode resonances that have distinctive electric field distributions. We present and validate the uni-polarized dual resonance approach to separating bulk index perturbations from surface-binding events in a single measurement by monitoring the resonance wavelength shifts. This self-referencing method will reduce errors in the measurement of biomolecule binding events on sensor surfaces in a perturbed environmental background.

High aspect ratio nano-fabrication of photonic crystal structures on glass wafers using chrome as hard mask.

Wafer-scale nano-fabrication of silicon nitride (Si x N y ) photonic crystal (PhC) structures on glass (quartz) substrates is demonstrated using a thin (30 nm) chromium (Cr) layer as the hard mask for transferring the electron beam lithography (EBL) defined resist patterns. The use of the thin Cr layer not only solves the charging effect during the EBL on the insulating substrate, but also facilitates high aspect ratio PhCs by acting as a hard mask while deep etching into the Si x N y . A very high aspect ratio of 10:1 on a 60 nm wide grating structure has been achieved while preserving the quality of the flat top of the narrow lines. The presented nano-fabrication method provides PhC structures necessary for a high quality optical response. Finally, we fabricated a refractive index based PhC sensor which shows a sensitivity of 185 nm per RIU.

Emerging optofluidic technologies for point-of-care genetic analysis systems: a review.

This review describes recently emerging optical and microfluidic technologies suitable for point-of-care genetic analysis systems. Such systems must rapidly detect hundreds of mutations from biological samples with low DNA concentration. We review optical technologies delivering multiplex sensitivity and compatible with lab-on-chip integration for both tagged and non-tagged optical detection, identifying significant source and detector technology emerging from telecommunications technology. We highlight the potential for improved hybridization efficiency through careful microfluidic design and outline some novel enhancement approaches using target molecule confinement. Optimization of fluidic parameters such as flow rate, channel height and time facilitates enhanced hybridization efficiency and consequently detection performance as compared with conventional assay formats (e.g. microwell plates). We highlight lab-on-chip implementations with integrated microfluidic control for "sample-to-answer" systems where molecular biology protocols to realize detection of target DNA sequences from whole blood are required. We also review relevant technology approaches to optofluidic integration, and highlight the issue of biomolecule compatibility. Key areas in the development of an integrated optofluidic system for DNA hybridization are optical/fluidic integration and the impact on biomolecules immobilized within the system. A wide range of technology platforms have been advanced for detection, quantification and other forms of characterization of a range of biomolecules (e.g. RNA, DNA, protein and whole cell). Owing to the very different requirements for sample preparation, manipulation and detection of the different types of biomolecules, this review is focused primarily on DNA-DNA interactions in the context of point-of-care analysis systems.