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We present an integrated photoacoustic and ultrasonic three-dimensional (3D) volumetric imaging system based on a two-dimensional (2D) matrix array ultrasound probe. A wavelength-tunable dye laser pumpedby a Q-switched Nd:YAG laser serves as the light source and a modified commercial ultrasound imaging system (iU22, Philips Healthcare) with a 2D array transducer (X7-2, Philips Healthcare) detects both the pulse-echo ultrasound and photoacoustic signals. A multichannel data acquisition system acquires the RF channel data. The imaging system enables rendering of co-registered 3D ultrasound and photoacoustic images without mechanical scanning. The resolution along the azimuth, elevation, and axial direction are measured to be 0.66 mm, 0.91and 0.84 mm for photoacoustic imaging. In vivo 3D photoacoustic mapping of the sentinel lymph node was demonstrated in a rat model usingmethylene blue dye. These results highlight the clinical potentialof 3D PA imaging for identification of sentinel lymph nodes for cancer staging in humans.

In the paper, an improved link adaptation scheme is proposed for theWiMedia MB-OFDM UWB system, in which quality of service (QoS) support is provided. The proposed scheme consists of three functional blocks: link quality indicator (LQI) calculator, frame error rate (FER)estimator, and transmitter (TX) parameter selector. Instead of using the average receive SNR (ASNR) as LQI, a new LQI metric is definedbased on a union bound analysis to capture the effects of both pathloss and frequency selectivity of an instantaneous UWB channel. Howto calculate LQI for each rate mode is investigated by analyzing the distribution of soft bit information. With the calculated LQI, theFER performance of each rate mode can be accurately estimated witha look-up table method, which is suitable for practical implementation. Using the estimated FERs, TX parameter selector can optimize TXrate mode to improve the communication throughput under QoS constraints. It is shown the proposed scheme can significantly improve the throughput while maintaining the required QoS compared to conventional ASNR based link adaptation schemes.

Differential phase-contrast imaging in the x-ray domain provides three physically complementary pieces of information: the attenuation,the differential phase-contrast, related to the refractive index, and the dark-field signal, related to the total amount of radiation scattered into very small angles. In medical applications, it is of the utmost importance to present to the radiologist all clinically relevant information in as compact a way as possible. Hence, the needarisis for a method to combine two or more of the above mentioned images into one image containing all information relevant for diagnosis. We present an image composition algorithm that fuses the attenuation image and the differential phase contrast image into a composite image. The composition is performed in a noise optimal way such that the composite image is characterized by minimal noise-power at each frequency component.

Recent developments in the spectrum policy and regulatory domains allow more flexible and efficient use of spectrum, notably the releaseof National Broadband Plan, the publication of final rules for TV white spaces, and the ongoing proceeding for secondary use of the 2360–2400 MHz band for Medical Body Area Networks (MBANS). These important changes open up great opportunities for cognitive radio (CR) toenable and support a variety of emerging applications, ranging fromsmart grid, public safety, broadband cellular, to medical applications. This article presents a high-level view on how cognitive radio (primarily from a dynamic spectrum access perspective) would supportsuch applications, the benefits that cognitive radio would bring, and also some challenges that are yet to be resolved. We also highlight related standardization that uses cognitive radio technologies tosupport such emerging applications.

In Q3 of 2011, Philips Research received a brief from the Skin Carecategory of the Philips Consumer Lifestyle sector to explore the feasibility of heat and ultrasound to increase skin uptake of active skin whitening ingredients from cosmetics. Philips Research Asia-Shanghai performed an in-vivo study which aimed to answer two questions:1. Shows heat or ultrasound any efficacy in this context? 2. If an enhancement can be achieved, which technology is more suitable for ahome-use device? This report summarizes the research activities which have been conducted in Shanghai over Q3-Q4 of 2011 to answer thesequestions. Furthermore, mechanisms behind heat- and ultrasound-mediated permeation enhancement are introduced and discussed including mathematical models which can be used to predict permeation behaviourbased on physiochemical properties of a penetrant.

Medical Body Area Network (MBAN) technology provides a promising solution to improve patient care outcomes and lower healthcare costs. However, the current spectrum allocation cannot cater to increasing MBAN applications. Therefore, U.S., as well as other regions, have already been considering allocating a new spectrum for MBAN applications. In this paper we study a joint MBAN regulation proposal developed by Philips Healthcare, GE Healthcare, and AFTRCC that was recently presented to the FCC for the U.S. MBAN spectrum regulation. A brief summary of the joint proposal is firstly presented. Then the technical rationale behind the proposed parameters, such as frequency band selection, emission bandwidth limit, and transmission power limit, is discussed in detail. Link budget analysis and MBAN coexistencesimulations are given to demonstrate that the proposed solution canaddress the requirements of MBAN application.

Connected and interoperable healthcare system promises to reduce thecost of the healthcare delivery, increase its efficiency and enableconsumers to better engage with clinicians and manage their care. However at the same time it introduces new risks towards security andprivacy of personal health information, which are considered to beprominent impediments towards the realization of full benefits of connected health. In the connected healthcare system of future, different security technologies will be used to address security risks indifferent trust domains. For the domain of personal health and healthy lifestyle services, which is less trusted, additional security mechanisms (e.g. digital rights management) are required next to access control which is traditionally used in the professional medical domain. To realize the vision of connected health, all these mechanisms should be interoperable with each other. In this paper we providean interoperability framework which allows digital rights managementand access control systems to seamlessly work together through theuse of ontology.

In this paper, we study the transmission strategy in a two-way relaychannel. In particular, we propose a new class of log_M1 (M_2)-MA (multi-access) block relay protocols where an M_1-ary modulation is used in the MA phase, and an M_2-ary in the broadcast phase. Lower-order (e.g., BPSK) and higher-order (e.g., 16-QAM, 32-PSK)modulations are used respectively for the multi-access phase and thebroadcast phase, in contrast to the conventional method of using the same modulation type (of either higher or lower order) throughout.To achieve this, the relay buffers the received symbols from consecutive multi-access phases and performs signal combining in conjunction with the decode-and-forward protocol. We derive the theoretical performance bounds for the Rayleigh fading channels and closed formsfor the AWGN channels. Numerical results confirm the advantages of the proposed scheme with an improved throughput in lower signal-to-noise ratio range.

A Simultaneous Non-contrast Angiography and intraPlaque hemorrhage (SNAP) MR imaging technique was proposed to detect both luminal stenosis and hemorrhage in atherosclerosis patients in a single scan. 13patients with diagnosed carotid atherosclerotic plaque were recruited after informed consent. All scans were performed on a 3T MR imaging system with SNAP, 2D time-of-flight (TOF) and magnetization-prepared 3D rapid acquisition gradient echo (MP-RAGE) sequences. The SNAPsequence utilized a phase sensitive acquisition, and was designed toprovide positive signals corresponding to intraplaque hemorrhage (IPH) and negative signals corresponding to lumen. SNAP images were compared to TOF images to validate lumen area measurements using linear mixed models and the intraclass correlation coefficient (ICC). IPHidentification accuracy was evaluated by comparing to MP-RAGE images using Cohen’s Kappa. Diagnostic quality SNAP images were generatedfrom all subjects. Quantitatively, the lumen area measurements by SNAP were strongly correlated (ICC=0.96, p<0.001) with those measuredby TOF. For IPH detection, strong agreement (&#954;=0.82, p<0.001)was also identified between SNAP and MP-RAGE images. The SNAP technique was proposed and validated to reliably detect in a single acquisition both luminal size and intraplaque hemorrhage in the patients with carotid atherosclerosis.

Providing the right amount of light where and when it is needed is an opportunity to transform today’s cities into smart and livable urban spaces. New technologies are being introduced, such are adaptivecontrols and outdoor lighting networks, which can deliver energy andcost savings through adaptive lighting and streamlined maintenance.However, the full market potential for such systems has not been achieved. A number of issues have been hampering the market, from lackof clarity in adaptive lighting regulations, to system interoperability, cost and complexity issues. Standards and recommended practices that drive regulation on adaptive lighting are paramount to clearing the way to large scale deployment of intelligent and energy efficient lighting. Existing recommended practices do not explicitly address adaptive lighting requirements. In the area of communication technologies, the lighting industry has been trying to leverage existing standards, such as Internet protocols (TCP/UDP, IP) and connectivity standards (wireless and power line). However, the diversity of approaches in applying them has resulted in incompatible solutions atmultiple levels. On the other hand, it should be recognized that thetotal solution typically requires customizations to address problems beyond what is defined in existing connectivity standards. Therefore, there is a clear need for a balanced approach where standards can be developed to bring immediate value to customers by leveraging mature technologies, while leaving room for innovation.

Glycogen storage disease type Ia (GSDIa) is caused by an inherited single-gene defect resulting in an impaired glycogen to glucose conversion pathway. Targeted ultrasound mediated delivery (USMD) of plasmid DNA to liver in conjunction with microbubbles may provide a potential treatment for GSDIa patients. As the success of USMD treatmentsis largely dependent on the accessibility of the targeted tissue bythe focused ultrasound beam, this study presents a quantitative approach to determine the acoustically accessible liver volume in GSDIapatients. Models of focused ultrasound beam profiles for transducers of varying aperture and focal lengths were applied to abdomen models reconstructed from suitable CT and MRI images. Transducer manipulations (simulating USMD treatment procedures) were implemented via transducer translations and 2D rotations with the intent of targetingand exposing the entire liver to ultrasound. Results indicate thatacoustically accessible liver volumes can be as large as 60% of theentire liver volume for GSDIa patients and on average 3 times largercompared to a normal group due to GSDIa patients’ increased liver size. Detailed descriptions of the evaluation algorithm, transducer-and abdomen models will be presented, together with implications forUSMD treatments of GSDIa patients and transducer designs for USMD applications.

Photoacoustic tomography (PAT) is a molecular imaging technology. Unlike conventional reporter gene imaging, which is based on fluorescent proteins, photoacoustic reporter gene imaging is based on opticalabsorption. Using lacZ, one of the most widely used reporter genesin biology, this work demonstrated several key merits of PAT. We proved that the expression of lacZ can be imaged by PAT as deep as 5.0cm in biological tissue with resolutions of ~1.0 mm and ~0.4 mm in the lateral and axial directions, respectively. We further demonstrated non-invasive simultaneous imaging of a lacZ-marked tumor and itssurrounding microvasculature in vivo by dual-wavelength acoustic-resolution photoacoustic microscopy, with a lateral resolution of 45 µmand an axial resolution of 15 µm. Finally, using optical-resolutionphotoacoustic microscopy, we showed sub-cellular localization of lacZ expression, with a lateral resolution of a fraction of a micron.These results suggest that PAT is potentially a complementary tool to conventional optical fluorescence imaging of reporter genes for linking biological studies from the microscopic to the macroscopic scales.

GSD1a, the most prevalent type among the glycogen storage disease families, is caused by an inherited glycogen-6-phosphatase gene defectresulting in an impaired glycogen to glucose conversion pathway. Strict dietary management continues to be the only treatment for GSD1apatients. Recently, the advent of targeted ultrasound mediated delivery (USMD) of pDNA to the liver of GSD1a patients in conjunction with microbubbles may provide an alternative treatment option. As thesuccess of USMD of agents is largely dependent on the accessibilityof the targeted tissue by the ultrasound beam, there is a need to quantitatively determine this parameter. For this reason, this study focused on determining the acoustically accessible liver volume in GSD1a patients using transducer models of various apertures and focallengths using suitable CT and MRI datasets, following a geometry-driven approach. Results show that GSD1a patients generally have a larger acoustic accessible liver volume compared to a normal patient group for a given transducer geometry, and that transducers with a smaller aperture and longer focal length would be better suited for these applications. This data is a necessary initial design criterion for ultrasound mediated delivery systems for liver applications in general, and USMD pDNA delivery systems to the liver for GSD1a patientsin particular.

We developed a tri-modality imaging system for breast cancer imagingby integrating photoacoustic (PA) and thermoacoustic (TA) imaging techniques into a modified commercial ultrasound scanner. Laser and microwave excitation pulses were interleaved to enable PA and TA dataacquisition in parallel at the rate of 10 frames per second. The performance of the tri-modality imaging system was evaluated in-vitrousing phantom samples. A plastic tube (7 mm inner diameter, 25 mm length) filled with 30 mM methylene blue dye placed at a depth of 8.4cm in chicken breast tissue was successfully detected in PA images with an ultrasonic bandwidth of 1–5 MHz. The SNR at this depth was 15dB after averaging 200 signal acquisitions. Similarly, a plastic tube (7 mm inner diameter, 25 mm length) filled with high concentration salt water placed at a depth of 5.1 cm in porcine fat tissue was successfully detected in TA images. A PA noise-equivalent-sensitivityto methylene blue solution of 260 nM was achieved in chicken tissueat a depth of 3.4 cm and with a laser fluence of 17 mJ/cm2.

Backgroud: This study was to validate the feasibility of using clinical 3.0T MRI to monitor the migration of autotransplanted bone marrow (BM)-derived stem-progenitor cells (SPC) to the injured arteries of near-human sized swine for potential cell-based arterial repair.Methodology: The study was divided into two phases. For in vitro evaluation, BM cells were extracted from the iliac crests of 13 domestic pigs and then labeled with a T2 contrast agent, Feridex, and/or afluorescent tissue marker, PKH26. The viability, the proliferation efficiency and the efficacies of Feridex and/or PKH26 labeling were determined. For in vivo validation, the 13 pigs underwent endovascular balloon-mediated intimal damages of the iliofemoral arteries. Thelabeled or un-labeled BM cells were autotransplanted back to the same pig from which the BM cells were extracted. Approximately three weeks post-cell transplantation, 3.0T T2-weighted MRI was performed todetect Feridex-created signal voids of the transplanted BM cells inthe injured iliofemoral arteries, which was confirmed by subsequenthistologic correlation. Principal Findings: Of the in vitro study,the viability of dual-labeled BM cells was 95-98%. The proliferation efficiencies of dual-labeled BM cells were not significantly different compared to those of non-labeled cells. The efficacies of Feridex- and PKH26 labeling were 90% and 100%, respectively. Of the in vivo study, 3.0T MRI detected the auto-transplanted BM cells migratedto the injured arteries, which was confirmed by histologic examinations. Conclusion: This study demonstrates the capability of using clinical 3.0T MRI to monitor the auto-transplantation of BM cells thatmigrate to the injured arteries of large animals, which may providea useful MRI technique to monitor cell-based arterial repair.