Over the last decade the changing healthcare environment has required hospitals and specifically Biomedical Engineering to critically evaluate, optimize and adapt their operations. The focus is now on new technologies, changes to the environment of care, support requirements and financial constraints. Memorial Sloan Kettering Cancer Center (MSKCC), an NIH-designated comprehensive cancer center, has been transitioning to an increasing outpatient care environment. This transition is driving an increase in-patient acuity coupled with the need for added urgency of support and response time. New technologies, regulatory requirements and financial constraints have impacted operating budgets and in some cases, resulted in a reduction in staffing. Specific initiatives, such as the Joint Commission's National Patient Safety Goals, requirements for an electronic medical record, meaningful use and ICD10 have caused institutions to reevaluate their operations and processes including requiring Biomedical Engineering to manage new technologies, integrations and changes in the electromagnetic environment, while optimizing operational workflow and resource utilization. This paper addresses the new and expanding responsibilities and approach of Biomedical Engineering organizations, specifically at MSKCC. It is suggested that our experience may be a template for other organizations facing similar problems. Increasing support is necessary for Medical Software - Medical Device Data Systems in the evolving wireless environment, including RTLS and RFID. It will be necessary to evaluate the potential impact on the growing electromagnetic environment, on connectivity resulting in the need for dynamic and interactive testing and the growing demand to establish new and needed operational synergies with Information Technology operations and other operational groups within the institution, such as nursing, facilities management, central supply, and the user departments.

Rapidly changing technology coupled with the financial impact of organized health care, has required hospital Biomedical Engineering organizations to augment their traditional operational and business models to increase their role in developing enhanced clinical applications utilizing new and evolving technologies. The deployment of these technology based applications has required Biomedical Engineering organizations to re-organize to optimize the manner in which they provide and manage services. Memorial Sloan-Kettering Cancer Center has implemented a strategy to explore evolving technologies integrating them into enhanced clinical applications while optimally utilizing the expertise of the traditional Biomedical Engineering component (Clinical Engineering) to provide expanded support in technology / equipment management, device repair, preventive maintenance and integration with legacy clinical systems. Specifically, Biomedical Engineering is an integral component of the Medical Physics Department which provides comprehensive and integrated support to the Center in advanced physical, technical and engineering technology. This organizational structure emphasizes the integration and collaboration between a spectrum of technical expertise for clinical support and equipment management roles. The high cost of clinical equipment purchases coupled with the increasing cost of service has driven equipment management responsibilities to include significant business and financial aspects to provide a cost effective service model. This case study details the dynamics of these expanded roles, future initiatives and benefits for Biomedical Engineering and Memorial Sloan Kettering Cancer Center.

A novel grating-assisted wavelength selective switch (WSS) is proposed. Its operating principle is experimentally confirmed with strong coupling strength, negligible birefringence, and low channel crosstalk. A WSS-based cross-connect device is demonstrated.

Numerical simulators for InP/InGaAsP laser diodes developed at NTT Opto-electronics Laboratories are reviewed. The programs are classified into two categories. One is overall simulation programs for designing optimum device structures such as low threshold designing by suppressing leakage current and reduced spatial hole burning designing. Carrier transport equations together with optical wave equation are solved self-consistently. Since the programs classified in this category are used repeatedly, user-friendly graphic interfaces are prepared during input and output stages. The other is an active layer design program based upon accurate physics such as strain and/or quantum well bandslructures. In this article, these simulators are introduced together with the more interesting results.

The deployment of new wireless and networked technology and advanced clinical applications has significantly increased the quality and the quantity of patient diagnostic and monitoring information throughout the patient care environment. Coupled with increasing workloads and reduced staffing, the difficulties in effectively prioritizing and handling this information have resulted in a rise in equipment-related errors, patient dissatisfaction, a potential for patient injury, and an increasing overall concern for patient safety. Concerns about this trend have prompted the Joint Commission to established seven patient safety initiatives geared to the patient environment of care, establishing methodologies and protocols to reduce the probability of errors, and to provide an enhanced level of communications. Planned deployment of advanced medical devices and supporting technologies coupled with our existing wired/wireless network infrastructure, need to consider the potential integrating clinical device, onto a unified network infrastructure providing advanced capabilities to share and effectively manage this key patient clinical information. Implementation of a biomedical device information network represents a significant advance in the management of clinical patient information, and enables device data, specifically critical patient alarms to be shared, coordinated, prioritized and sent directly to specific assigned care providers. The care giver utilizing a common hands-free wireless device can receive a prioritized audible (or a simulated voice) alarm message and utilize this same device for directed staff-to-staff or staff-to-patient communication. The Biomedical Information Network implementation identifies or associates patients with devices and consequently critical alarms, filters low priority or nuisance alarms, and eliminates the need for multiple costly communication devices. This implementation establishes an enhanced environment of care, providing increased patient safety, and a clear proactive response to the national patient safety initiatives.

Rapidly changing technology coupled with the financial impact of organized health care, has required hospital Biomedical Engineering organizations to augment their operational and business models to increase their role in technology research, and optimize the manner in which they provide and manage services. Memorial Sloan-Kettering Cancer Center has implemented a strategy to optimally utilize the expertise of Biomedical Engineering to provide support in technology/equipment management, device repair and preventive maintenance and in addition to participate in the investigation of new and evolving technologies and in research and development Specifically, Biomedical Engineering is an integral component of the Medical Physics Department which provides comprehensive and integrated support to the center in advanced physical, technical, engineering technologies This organizational structure emphasizes the integration and collaboration between a spectrum of technical expertise for clinical support and equipment management roles. Equipment management responsibilities have expanded to high-end, high cost devices minimizing response time, maximizing uptime and significantly reducing service cost. Specifically focused groups within Biomedical Engineering have been established to participate in the investigation and deployment of new and evolving technologies. This case study details the dynamics of these expanded roles, future initiatives and benefits for Biomedical Engineering and Memorial Sloan Kettering Cancer Center.

He-Zhao deficiency has been recently characterized with a distinct form of agenesis of permanent teeth that is different from other previously reported disorders of tooth agenesis. This inherited abnormality suggests that some gene(s) associated with the development of permanent teeth may mutate. In this study, we map the gene locus to chromosome 10q11.2. The DNA pooling method combined with two-point and multi-point linkage analysis has been successfully applied. The maximum LOD (Zmax) scores for two-point and multi-point analyses are 13.29 (on marker D10S196) at recombination fraction (θ) = 0 and 18.09 (between markers D10S1772 and D10S1766), respectively. Haplotype analysis confined the locus within an interval of 5.5 cM flanked by markers D10S604 and D10S568. This study has demonstrated a novel gene locus responsible for He-Zhao deficiency and provides a good likelihood for the discovery of one of the genes determining permanent tooth formation and development.

A new explicit fourth-order finite-difference time-domain (FDTD) scheme for three-dimensional electromagnetic field simulation is proposed in this paper. A symplectic integrator propagator, which is also known as a decomposition of the exponential operator or a general propagation technique, is directly applied to Maxwell's equations in the scheme. The scheme is nondissipative and saves memory. The Courant stability limit of the scheme is 30% larger than that of the standard FDTD method. The perfectly matched layer absorbing boundary condition is applicable to the scheme. A specific eigenmode of a waveguide is successfully excited in the scheme. Stable and accurate performance is demonstrated by numerical examples.

The reflection coefficient at the dielectric interface orthogonal to the Yee-lattice axis in the finite-difference time-domain (FDTD) scheme is explicitly obtained. In the expression, the effective permittivities assigned to the nodes in the vicinity of the interface are included as parameters. The suitable effective permittivities for the accurate modeling of the interface are investigated theoretically based on the reflection coefficient. Regardless of the angular frequency, the incident angle, and the interface position relative to the lattice, second-order accuracy is achieved by the use of effective permittivities based on the weighted harmonic mean and arithmetic mean of the material permittivities. The second-order accuracy is demonstrated by numerical examples.

When electric field diverges at corners of optical waveguides, conventional numerical techniques such as the finite-difference method cannot be used for discretization of the wave equations. We have developed an algorithm for modal analysis such that singularity points at corner regions are handled properly. Calculation results are also shown to illustrate the effectiveness of this method.

Successful applications of the perfectly matched layer (PML)-absorbing boundary condition (ABC) to the symplectic finite-difference time-domain (FDTD) scheme are demonstrated. The scheme employs the 4th-order symplectic integrator propagator. The scheme is highly accurate and memory savable. This demonstration opens the door to the practical application of the scheme.

The use of a more accurate scheme is effective in reducing the required memory resources in the explicit time-domain simulation of optical field propagation. A promising technique is the application of the symplectic integrator, which can simulate the long-term evolution of a Hamiltonian system accurately, The stability condition and the numerical dispersion of schemes with fourth-order accuracy in time and space using the symplectic integrator are derived for the transverse electric (TE)-mode in two dimensions. Their stable and accurate performance is qualitatively verified, and is also demonstrated by numerical simulations of wave-converging by a perfect electric conductor wall and propagation along a waveguide whose refractive index difference between the core and cladding is more than 9%.

Beam propagation method (BPM) has been one of the most popular methods for simulation of electromagnetic wave propagation in optical waveguides.

Device characteristics of optical polarization rotators are founded upon the vector properties of the Maxwell Equations. Recently, a bending waveguide based polarization rotator has been proposed and demonstrated. To provide a rigorous basis for the analysis and design of this polarization rotator, the full-vectorial wave equations for both (E) over right arrow- and (H) over right arrow-field in bending waveguides are derived. It is found from these wave equations that under a broad range of circumstances, a bending waveguide can be analyzed using the equivalent straight waveguide approximation, Details of the model for optical polarization rotators, which is based on the coupled-mode theory, will be described in a companion paper.