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This paper provides an overview of a recently integrated health care system's experience in evolving their multi-component interprofessional approach to falls prevention. The approach was driven by review of local data, evidence-informed practices, and a mandate to sustain Magnet® designation with falls with injury being a required indicator for the Magnet Recognition Program®. Challenges and insights are also discussed.

Theoretical and experimental approaches verifying the fluidic operation of a partially shielded digital microfluidics device are presented in this paper. This paper is motivated by recent demand from the synthetic biology community for electrowetting on dielectric (EWD) enabled in-droplet electroporation, but is generalizable to a range of EWD applications that require shielding structures to be patterned on the EWD. An electrode patterned in an additional metal layer on the insulator that supports EWD actuation reduces the effective strength of the EW force due to dielectric shielding at the droplet contact line. A numerical model was developed to predict the impact of the partially shielding electrode on threshold voltage, EW force, fluid velocity, and droplet transport time. Compared with a batch of devices lacking the extra electrode, the presence of the added metal layer resulted in a 29% increase in threshold voltage, an 82% increase in transport time, and a 44% decrease in average transport velocity. Each trend agrees with the simulation results obtained from the fluid transport model. These results support the development of design rules for microfluidic devices that require partially shielding metal layers to integrate with EWD device architectures. [2016-0034]

Electrowetting-on-dielectric (EWD) digital microfluidic laboratory-on-a-chip platforms demonstrate excellent performance in automating labor-intensive protocols. When coupled with an on-chip electroporation capability, these systems hold promise for streamlining cumbersome processes such as multiplex automated genome engineering (MAGE). We integrated a single Ti:Au electroporation electrode into an otherwise standard parallel-plate EWD geometry to enable high-efficiency transformation of Escherichia coli with reporter plasmid DNA in a 200 nL droplet. Test devices exhibited robust operation with more than 10 transformation experiments performed per device without cross-contamination or failure. Despite intrinsic electric-field nonuniformity present in the EP/EWD device, the peak on-chip transformation efficiency was measured to be 8.6 ± 1.0 × 108 cfu·μg–1 for an average applied electric field strength of 2.25 ± 0.50 kV·mm–1. Cell survival and transformation fractions at this electroporation pulse strength ...

Electrowetting-on-dielectric (EWD) microfluidics is an emerging platform for practical applications such as water quality testing and medical diagnostics. Low power consumption, low sample and reagent volumes, small size, and rapid fluid transport are features of electrowetting microfluidic platforms that will enable the development of cost-effective, rapid time-to-result, and portable point-of-care diagnostic devices. Microresonator sensors are an excellent sensor technology for integration into these microfluidic systems, because they perform high sensitivity detection of proteins, DNA, and other biologically relevant molecules while tolerating a droplet oil encapsulation layer. This paper reports on a SU-8 polymer microresonator embedded in the top plate of the EWD system, which enables addressing of the sensor with a single droplet of in volume and enables droplets to be moved onto and off of the sensor. This system is the first to demonstrate actuation of droplets onto and off of an integrated microresonator sensor. Both photolithographically patterned and electron beam lithographically patterned microresonator sensors were tested, and the effect of a conventional filler medium, silicone oil, on the sensor sensitivity was investigated.

Miniaturized, portable, sensitive, and low cost sensing systems are important for medical and environmental diagnostic and monitoring applications. Chip scale integrated photonic sensing systems that combine optical, electrical, and fluidic functions are especially attractive for sensing applications due to the high sensitivity of optical sensors, the small form-factor of chip scale systems, and the low-cost processing possible for systems fabricated with well-developed mass production techniques. In this paper, a chip scale sensing system, which is composed of a planar integrated optical microdisk resonator and a thin film InGaAs photodetector, is integrated with a digital microfluidic system. This system was designed, fabricated, and experimentally characterized by dispensing and moving droplets of glucose solution from the reservoir to the microresonator sensor. The optical output of the resonator was transduced by the integrated photodetector to an electrical current signal for readout.

Portable point-of-care (POC) medical diagnostic devices demand low power consumption, efficient use of low sample and reagent volumes, and small size. A “digital” electrowetting-on-dielectric (EWD) microfluidics system with integrated optical sensors is a promising platform for portable POC diagnostic devices that integrate sample preparation with sensing. Herein is reported the highest sensitivity and figure of merit (FOM) microresonator sensor integrated with an EWD system to date [FOM is the product of the quality (Q) factor and the sensitivity (S)]. The EWD system embedded microresonator sensor had a measured FOM of 0.60 × 106 nm/RIU (Q = 8,400, S = 72 nm/RIU) in 2-cSt silicone oil and water, which is nearly double the best FOM previously reported for an microresonator placed on top of an EWD system. Additionally, a nominal FOM of 1.2 × 106 nm/RIU (Q = 15 000, S = 82 nm/RIU) was measured for the vertically coupled sensor fabricated on a standard SiO2/Si substrate. This FOM is the highest reported to date for SU-8 microresonators probed at wavelengths around 1550 nm. These results indicate that high-performance polymer sensors can be integrated with low-power-consumption EWD microfluidics sample preparation systems toward the development of portable POC diagnostic devices.

Chip-scale integrated planar photonic sensing systems for portable diagnostics and monitoring are emerging, as photonic components are integrated into systems with silicon (Si), Si complementary metal-oxide semiconductor, and fluidics. This paper reviews progress in these areas. Medical and environmental applications, candidate photonic sensors, integration methodologies, integrated subsystem demonstrations, and challenges facing this emerging field are discussed in this paper.

Medicine, environmental monitoring, and security are application areas for miniaturized, portable sensing systems. The emerging integration of sensors with other components (electronic, photonic, fluidic) is moving sensing toward higher levels of portability through the realization of self-contained chip scale sensing systems. Planar optical sensors, and in particular, microresonator sensors, are attractive components for chip scale integrated sensing systems because they are small, have high sensitivity, can be surface customized, and can be integrated singly or in arrays in a planar format with other components using conventional semiconductor fabrication technologies. This paper will focus on the progress and prospects for the integration of microresonator sensors at the chip scale with photonic input/output components and with sample preparation microfluidics, toward self-contained, portable sensing systems. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The intimate integration of digital electrowetting microfluidics and optical microcavity sensors results in an excellent platform for low power consumption, high sensitivity integrated sample preparation and testing, which is particularly useful for medical diagnostics and water quality testing. In this work, a microresonator structure with a buried channel waveguide (resulting in an external Q factor of 28,000 in silicone oil and 17,000 in water) was embedded in the top plate of a digital electrowetting system, enabling sensing with a single droplet of

Miniaturized, portable sensing systems for medical and environmental diagnostics and monitoring are an excellent application area for microresonator sensors. Polymer microresonators are attractive components for chip scale integrated sensing because they can be integrated in a planar format using standard semiconductor manufacturing technologies. Vertically coupled microresonators, where the waveguides lie below or above the microresonator, can be fabricated using standard photolithography, enabling low cost integrated sensor systems. Microresonators can be surface customized for discrimination in, for example, chemical sensing applications, or the surface can be functionalized for biological sensing applications. To create chip scale integrated sensing systems, microresonators can be integrated with planar optical system components, such as polymer waveguides and thin film photodetectors, onto silicon using heterogeneous integration. Heterogeneous integration can also be used to integrate optical sources with sensors onto host substrates such as silicon.

Free space optical (FSO) communications technology has potential applications in the military sector to provide a secure, high speed communication channel, and in the civilian sect or as a “last mile” carrier solution. It was proposed by other researchers that a multi-rate communication system that utilizes Meyer wavelets would achieve the greatest bandwidth and highest reliability possible for an FSO system [1]. In order to generate Meyer wavelets from femtosecond laser pulses, filtering must be performed optically to produce the desired pulse sh ape. One of the simplest ways to produce an arbitrary pulse shape from a laser pulse is with a tunable liquid-crystal spatial light modulator (LC-SLM) in a zero-dispersion pulse compressi on system. The simplest approach to determine the correct mask pattern for an LC-SLM is to utilize adaptive, global optimization methods. Since it takes several milliseconds to adjust the attributes of each pixel of an LC-SLM and there are typically over one-thousand pixels, it is important to determine the fastest algorithm for determining the optimum mask pattern. Several global optimization methods, including simulated annealing, exhaustive search, and random search, a hybrid of the other two algorithms, were characterized. It was found that exhaustive search can be used to form waveforms with ne gligible inaccuracies at rates of about 5 times faster than simulated annealing and about 3 times faster than random search, but that simulated annealing provides the highest accuracy. However, the difference in accuracy be tween all of these algorithms is less than 10

We demonstrate an electrolyte-based voltage tunable vanadium dioxide (VO2) memory metasurface. Large spatial scale, low voltage, non-volatile switching of terahertz (THz) metasurface resonances is achieved through voltage application using an ionic gel to drive the insulator-to-metal transition in an underlying VO2 layer. Positive and negative voltage application can selectively tune the metasurface resonance into the “off” or “on” state by pushing the VO2 into a more conductive or insulating regime respectively. Compared to graphene based control devices, the relatively long saturation time of resonance modification in VO2 based devices suggests that this voltage-induced switching originates primarily from electrochemical effects related to oxygen migration across the electrolyte–VO2 interface.

This paper presents an optical element capable of multiplexing two diffraction patterns for two orthogonal linear polarizations, based on the use of non-resonant metamaterial cross elements. The metamaterial cross elements provide unique building blocks for engineering arbitrary birefringence. As a proof-of-concept demonstration, we present the design and experimental characterization of a polarization multiplexed blazed diffraction grating and a polarization multiplexed computer-generated hologram, for the telecommunication wavelength of λ = 1.55 μm. A quantitative study of the polarization multiplexed grating reveals that this approach yields a very large polarization contrast ratio. The results show that metamaterials can form the basis for a versatile and compact platform useful in the design of multi-functional photonic devices.

Creation and control of spatial gradients in electromagnetic properties is a central theme underlying optical device design. In this work, we demonstrate that through modification of the spatial and temporal distribution of current, we can obtain increased control over the shape of these gradients. We are able to write spatially sharp gradients with ∼50% change in the index of refraction over length scales of only a few wavelengths as observed through diffraction limited terahertz spectroscopy. Furthermore, we assess the potentials for such gradients for beam-steering applications.

The planar integration of on-chip laser sources with optical sensing elements, waveguide optical interconnect, and detectors enables the implementation of portable, efficient chip-scale systems, with applications in areas that include medical, environmental, biological, and chemical sensing systems. In this paper, the planar integration of a thin film strain compensated In0.2Ga0.8As/GaAs single quantum well laser with a tapered polymer (SU-8-2002) waveguide and overlap coupled SU-8-2002 microring resonator is achieved on an SiO2/Si platform. Two laser/waveguide configurations, one with the tapered waveguide separated from the laser front facet and the other with the waveguide overlapping the front facet, were demonstrated, and this laser/waveguide structure was then integrated with a polymer microring resonator on SiO2/Si. Lasing operation for the integrated system was verified through power-current characteristics and spectra at the through and drop ports of the microring resonator. This integrated system forms an essential component toward realizing planar chip-scale optical sensing systems.

We demonstrate a metamaterial grating that has two diffraction periods for two orthogonal linear polarization states of illuminations. The proposed method will be useful in free space optical communications and novel optical imaging systems.

Franz Schubert wrote his masterpiece, the Lied Die Forelle, from the namesake light-hearted imaginative poem by C.F.D. Schubart, but by eliminating the last stanza from the Lied, he left the music and the text mismatched at the end and also left the fate of the trout in question. The Piano quintet in A “The Trout”, which was commissioned with the request that it be based on the Lied, was his answer to the above question. Indeed, the musical materials of stanzas #1 and 2, where the fish is joyously swimming, dominate the quintet, indicating that Schubert decided to let the fish escape and flourish in the quintet. He also used numerous musical formulations depicting the beauty of the watery world, formulations which were found in his many Lieder prior to the quintet. Moreover, a detailed analysis of the quintet, structurally and contextually, allowed us to suggest that Schubert formulated the quintet using the structure and narrative of the poem, which was transformed from the point of view of the poet to that of the trout. Thus the last stanza (#4) turned into an advice from the escaped trout to young female trout. Consequently quintet movements #1, 2, 3, and 4 corresponded to poem stanzas #1, 2, 3, and 4, respectively, followed by the last movement (#5) as the proverbial “they lived happily ever after”. Specifically, movement 4 (theme and variations) is suggested to be a musical depiction of the lecture given by the fish herself to the audience of young fish as follows: Thema (introduction), Variation I (my peaceful life in a brook), Variation II (the appearance of a fisherman), Variation III (teasing of the fisherman), Variation IV (getting caught, escaping and a long painful recovery), Variation V-Andante (the lesson I learnt and what I recommend, - and the audience responding), Variation V-Allegretto (fish dispersing, each vowing to be safe and free). It appears that Schubert took the terms of commission, - that the quintet was to be “based” on the Lied - very seriously. His effort resulted in a piece that is always enjoyable and can also be seen as a precursor to program music, which flourished much later in the Romantic period. Two years after the completion of the quintet, Schubert made the last revision to his Lied Die Forelle (version #5) with numerous changes which made the pair closely aligned to each other, opening the possibility of an integrated performance of the pair., Franz Schubert a écrit son chef-d'œuvre, le lied Die Forelle, à partir du poème imaginatif léger du même nom de C.F.D. Schubart. Mais en éliminant la dernière strophe du lied, il a rendu la musique et le texte incohérents à la fin et a également mis de côté le sort de la truite en question. Le quintette avec piano en la « La truite », qui a été commandé avec la demande qu'il soit basé sur le lied, a été sa réponse à la question ci-dessus. En effet, le matériel musical des strophes n° 1 et 2, où le poisson nage joyeusement, domine le quintette, indiquant que Schubert a décidé de laisser le poisson s'échapper et s'épanouir dans le quintette. Il a également utilisé de nombreuses formulations musicales illustrant la beauté du monde aquatique, formulations que l'on retrouve dans ses nombreux lieder avant le quintette. De plus, une analyse détaillée du quintette, structurellement et contextuellement, nous a permis de suggérer que Schubert a formulé le quintette en utilisant la structure et le récit du poème, qui a été transformé du point de vue du poète à celui de la truite. Ainsi la dernière strophe (n° 4) s'est transformée en un conseil de la truite qui s’est échappée à la jeune truite femelle. Par conséquent, les mouvements de quintette n° 1, 2, 3 et 4 correspondaient aux strophes de poème n° 1, 2, 3 et 4, respectivement, suivis du dernier mouvement (n° 5) en tant que proverbial « ils ont vécu heureux pour toujours ». Plus précisément, le mouvement 4 (thème et variations) est suggéré comme une représentation musicale de la conférence donnée par le poisson lui-même au public de jeunes poissons comme suit : Thema (introduction), Variation I (ma vie paisible dans un ruisseau), Variation II (l'apparition d'un pêcheur), Variation III (taquineries du pêcheur), Variation IV (se faire prendre, s'échapper et une longue guérison douloureuse), Variation V-Andante (la leçon que j'ai apprise et ce que je recommande, et le public qui répond), Variation V-Allegretto (les poissons se dispersent, chacun jurant d'être en sécurité et libre). Il semble que Schubert a pris les conditions de la commission, que le quintette devait être « basé » sur le lied, très au sérieux. Ses efforts ont abouti à une pièce toujours agréable et qui peut également être considérée comme un précurseur de la musique à programme, qui a prospéré beaucoup plus tard dans la période romantique. Deux ans après l'achèvement du quintette, Schubert a fait la dernière révision de son lied Die Forelle (version n° 5) avec de nombreux changements qui ont rendu la paire étroitement alignée l'une sur l'autre, ouvrant la possibilité d'une performance intégrée de la paire.