This PDF file contains the front matter associated with SPIE Proceedings Volume 10662, including the Title Page, Copyright information, Table of Contents, Introduction (if any), and Conference Committee listing.

This study provides excellent method to create large surface area and morphologies which can be used in drug delivery and for absorption of drugs. In addition provides knowledge about morphological transition

Recently there is a big thrust on bio-inspired sensors and there has been a large rise in the investment and expectations for nanotechnology to meet these goals. For in situ sensor development materials deposition on substrate is essential part of device development. Physical vapor deposition (PVD), chemical vapor deposition (CVD) and molecular organic vapor deposition methods have developed for growth of semiconductor bulk and thin film growth with some modifications have been used for these materials. Oxides and other elements of VI group such as sulfides and selenides are key components in skins of many species. Growth of ordered structures containing these elements have been achieved by using PVD method. This paper describes effect of growth parameters during PVD growth on the quality of materials. Growth kinetics and mechanism will be discussed for the vertical and horizontal growth reactors. Since most of the efficient materials systems are multinary and in many cases noncongruent, PVD provides pathway to grow materials below melting temperature.

We have prepared silicate based hard materials and have processed it with organic flux. Because of the bioactivities of hydroxyapatites with tissues, this class of materials have attracted interest for bone applications. We have utilized low temperature processing techniques. Organic melt was used and the directional solidification method to cast the shaped sample. This organic treated material has different characteristics than coarsened oxide materials. Our approach involved low temperature processing using nano and micron sized powders of the material system Na₂OK₂O- CaO- MgO-Ga₂O₃-SiO₂, and titanates were processed by sintering and grain growth. Our results indicate that substitution of gallium and magnesium or titanium with some variation in processing methods have great potential to improve the glassy characteristics without decreasing the mechanical properties of bones. Effect of radiation on bone was studied by exposing with commercially available Cs¹³⁷ gamma ray source. It was observed that electrical resistivity increased due to radiation exposure for this system.

Drug delivery is a very complex phenomenon. Most of the drugs are soluble in the water and flow easily in the body. However, drugs consisted of complex organics crystallize in different morphologies such as needles, plates, dendrites and organized lamellars. We have observed that 3.methoxy 4-hydroxybenzaldehyde also known as “vanillin” forms needles and plate morphologies in very small difference of pH or organic impurities and can crystallize in different forms. We have performed extensive studies to understand the crystallization of binary and ternary complex organic materials systems to understand the crystallization and morphologies. We will present the results of non-water-soluble organics using melt methods and discuss the mechanism of formation of different morphologies. More specifically results of 3.methoxy 4-hydroxybenzaldehyde-m.dinitrobenzene and 8- hydroxyquinoline-succinonitrile, systems will be discussed.

The requirement for solid, rigid structures for the ability to precisely control and manipulate acoustic waves can be highly limiting in applications such as biomedical imaging where sound manipulation and control through such interfaces cannot easily be employed. In this work, we describe the ability to generate optically induced reflective sound barriers and waveguides. These barriers are generated by creating abrupt density barriers via photothermal depletion of the transport medium along the path of a laser beam, causing sharp differences in compressibility, resulting in significant acoustic reflection. Using this technique, acoustic reflection efficiencies of 30% have been demonstrated. Furthermore, employing multiple optically induced acoustic reflective barriers sequentially can result in complete suppression of incident acoustic sound wave transmission. In addition to optically induced acoustic suppression, optical waveguiding can also be achieved using cylindrical, ring shaped laser beams. By containing the acoustic waves inside the cylindrical channel, dramatic improvements in acoustic transmission can be achieved. Optical waveguding of acoustic signals offers a new paradigm in the manipulation of sound over extended distances in various media, providing potentially significant improvements to photoacoustic sensing and imaging in many applications

There is a rise in the study of functional connectivity among various cortical regions and investigations to uncover causal links between a stimulus and the corresponding neural dynamics through electrophysiological imaging of the human brain. Animal model that exhibit simplistic representations of such networks open a doorway for such investigations and are gaining rapid popularity. In this study, we investigate and compare resting state network and auditory stimulus related activity with minimal invasive technology along computational spectral analysis on a C57/BL6 based mouse model. Somatosensory, motor and visual cortex are observed to be highly active and significantly correlated (p-value<0.05). Moreover, given the spatial limitation due to small size of the mouse head, we also describe a low-cost and effective fabrication process for the mouse EEG Polyimide Based Microelectrodes (PBM) array. The easy-to-implement fabrication process involves transfer of the pattern on a copper layer of the Kapton film followed by gold electroplating and application of insulation paint. Acoustic stimulation is done by using tube extensions for avoiding electrical coupling to EEG signals. Unlike multi-electrode array type of invasive methods that are local to a cortical region, the methods established in this study can be used for examining functional connectivity analysis, neural dynamics and cortical response at a global level.

This paper deals with a complex problem in scientific sensing and imaging. To overcome some inherent problems in the conventional ECG (Electrocardiogram), we investigate in depth an ‘unassisted’ approach which enables ECG measurement without the placement of sensing leads on the body. Specifically, it uses a bathtub at home with tap water in it and passive sensing leads placed on its inner surface – while the subject lies in it. In this investigation we use a widely accepted assumption that the electrical activity of the heart may be, largely, represented by a 3-D time-varying Current Dipole (3D-CD). To determine the sensing matrix responsible for transforming the 3D-CD into the potential distribution on the bathtub’s internal surface, the 3D-CD signals are applied to a bathtub-containing-ellipsoid model in COMSOL tool. The sensing matrix thereby estimated is then utilized to back reconstruct the 3D-CD signals from the bathtub leads signals. NRMSEs (Normalized Root-Mean-Squared Errors) on the order of 0.02 to 0.05 are observed. The approach is also successfully extended to the case of two ellipsoids, one inside the other, representing a pregnant female subject. Critically important from a practical standpoint, the paper examines sensitivity with respect to the locations of the two 3D-CDs in the bathtub, and reports the encouraging results. Images of the potential distribution in the composite volume in the bathtub are presented as well.

This paper discusses a system for unassisted monitoring of (a) adult ECG and (b) in case of pregnant mothers, the mother’s and the fetal ECG (fECG), the latter by its extraction from the overshadowing maternal ECG (mECG). We propose to monitor these vital signals from a bathtub at home with no leads placed on the subject’s body, therefore completely unassisted. The leads are passive, and placed permanently on the inner surface of the bathtub. DSP is used both for extracting the orthogonal vector-cardiogram from the bathtub leads and also for efficient separation of the fECG from the combined mother-and-fetal signal (mfECG) – taking into account a composite, highly complex, medium. Presented also is a novel architecture for on-chip processing based on application-specific CMOS VLSI cells developed in our laboratory.

Brain simulation techniques have demonstrated undisputable therapeutic effects on neural diseases. Invasive stimulation techniques like deep brain stimulation (DBS) and noninvasive techniques like transcranial magnetic stimulation (TMS) have been approved by FDA as treatments for many drug resist neural disorders and diseases. Developing noninvasive, deep, and targeted brain stimulation techniques is currently one of the important tasks in brain researches. Transcranial direct current stimulation (tDCS) and transcranial alternative current stimulation (tACS) techniques have the advantages of low cost and portability. However, neither of them can produce targeted stimulation due to lacking of electrical field focusing mechanism. Recently, Grossman et al. reported using the down beating signals of two tACS signals to accomplish focused stimulation. By sending two sine waves running at slightly different high frequencies (~2kHz), they demonstrated that they can modulate a “localized” neuron group at the difference frequency of the two sine waves and at the same time avoid excitation of neurons at other locations. As a result, equivalent focusing effect was accomplished by such beating mechanism. In this work, we show neither theoretically nor experimentally the beating mechanism can produce “focusing effect” and the beating signal spread globally across the full brain. The localized modulation effect likely happened right at the electrode contact sites when the electrode contact area is small and the current is concentrated. We conclude that to accomplish noninvasive and focused stimulation at current stage the only available tool is the focused TMS system we recently demonstrated.

Attention Deficit and Hyperactivity Disorder (ADHD) is associated with symptoms of inattention, hyperactivity, and impulsivity and affects a significant part of the population. Current treatment approaches entail high costs and are commonly based on stimulant medication, which may lead to undesirable side-effects. FocusLocus is an EU H2020 Innovation Action project that proposes a highly disruptive and innovative gamified monitoring and intervention programme for assisting children to manage and overcome ADHD symptoms. FocusLocus implements game mechanics that rely on cognitive training methods for mental and motor skill acquisition and behavioural change. The proposed programme is delivered through a multifaceted and adaptive gaming experience that permeates the child’s daily life and activities, spanning across virtual and physical space and comprising two modes: (a) a mobile tablet game for home use by individual users and (b) a multisensory mixed reality game for supervised sessions at specialised facilities (e.g., clinics). FocusLocus is designed to be highly personalised and adaptive to each child’s individual condition, symptoms, age, and character. By introducing advanced remote monitoring and management features, FocusLocus actively involves all stakeholders associated with children with ADHD (parents, clinicians, and special needs educators). FocusLocus employs an unobtrusive and multimodal sensing, assessment and monitoring methodology relying on (a) mobile device embedded sensors, (b) Electroencephalography (EEG) neurofeedback mechanisms, (c) Augmented Reality (AR) user tracking, (d) RFID-based object tracking for tangible user interaction, (e) in-game cognitive skill performance measurements, (f) cloud performance analytics, and (g) web-based secure access for remote profile monitoring and management.

This article presents a prototype of a wearable instrument for oxygen saturation and ECG monitoring. The proposed measuring system is based on the variability of the light reflection of a LED emission placed on the subject’s temple. Besides, the system has the capacity to incorporate electrodes to obtain ECG measurements. The activity of the user can be monitored through an accelerometer. All measurements are stored and transmitted to a mobile device (tablet or smartphone) through a Bluetooth link where the information is treated and shown to the user.

Point-of-care technologies have become increasingly important in diagnostic applications. Wireless capabilities provide easy storage and analysis of data. Thus, portable systems need to migrate to handheld versions. Previously we have been able to determine blood volume fraction and water content in human skin using near-infrared (NIR) imaging. We have also used this portable multispectral imager to successfully identify remission of disease after treatment in patients with Cushing disease. Here we present a handheld high resolution multispectral imager. This tool is designed to be light weight and easy to use to promote its use in any clinical setup. The device consists of a custom fabricated CMOS imaging camera with on-chip NIR filters, a 25mm lens and wireless communication electronics. Illumination is provided by a broad band incandescent lamp. The use of novel technology of on-chip filters avoids the need for large size filtering systems such as filter wheels, making it a handheld device. Eight NIR filters with wavelengths in the range 700 nm to 980 nm provide flexibility of detecting multiple chromophores in the skin such as oxy and deoxy hemoglobin, melanin etc. as well as water. Images are acquired simultaneously with exposure time of 300 ms to 500 ms. Each filtered image is about 340X340 pixel making it possible to use our curvature correction algorithm for accurate determination of parameters. Also, images at this resolution can provide reliable information about spatial variations. This tool can ultimately be used to the study other skin abnormalities such as Kaposi Sarcoma.

Diagnostically challenging breast tumors and Non-Mass-Enhancing (NME) lesions are often characterized by spatial and temporal heterogeneity, thus difficult to detect and classify. Differently from mass enhancing tumors they have an atypical temporal enhancement behavior that does not enable a straight-forward lesion classification into benign or malignant. The poorly defined margins do not support a concise shape description thus impacting morphological characterizations. A multi-level analysis strategy capturing the features of Non-Mass- Like-Enhancing (NMLEs) is shown to be superior to other methods relying only on morphological and kinetic information. In addition to this, the NMLE features such as NMLE distribution types and NMLE enhancement pattern, can be employed in radomics analysis to make robust models in the early prediction of the response to neo-adjuvant chemotherapy in breast cancer. Therefore, this could predict treatment response early in therapy to identify women who do not benefit from cytotoxic therapy.

Electrical Impedance Myography (EIM) is a painless, non-invasive electrophysiological technique for the assessment of different disease status of the human body. In EIM, high frequency, low-intensity electrical current is injected via the surface electrode to the localized area and resulting voltage patterns are analyzed using the voltage sensing electrode to access three major parameters-resistance(R), reactance(X), and phase(θ). This method detects the abnormalities in the biological tissue based on differences in values of these three parameters between normal and malignant tissue. In this study, a finite element model of the human breast has been developed in an attempt to analyze the EIM parameters for the detection of malignant tissue. Simulations were carried out for a frequency range of 2 to 3 GHz and electrical properties of breast tissue were used. For example, at 2.45 GHz, normal breast tissue has a resistance of .961 Ω and a reactance of 4.462 Ω. At this particular frequency, malignant breast tissue with a tumor size of 7 mm had a resistance of .945 ohm and reactance of 4.365 ohm. The percentage deviation of the normal breast tissue from the 7mm malignant tissue for resistance and reactance is 1.665% and 2.174% respectively. This paper attempts to illustrate the behavior of EIM parameters for different size and location of the tumor in the breast tissue. The ultimate goal of the paper is to investigate EIM’s ability to detect early cancer cell in the breast tissue.

A novel application of a highly sensitive biosensor based on long-period fiber gratings (LPFG) coated with microporous polyelectrolyte coating for Gram-negative bacteria detection was investigated. The uniform microporous coating with large surface area was fabricated with weak polyelectrolytes poly(allylamine hydrochloride) (PAH) and poly(acrylic acid) (PAA) via layer-by-layer (LbL) assembly, followed by a brief exposure to acidic aqueous solutions at pH=4. The diameter of the micropores could be adjusted in a wide range by thermal treatment and ionic etching. The effect of pore size and surface topography on bacteria adhesion was examinged. Optofluidic LPFG platform for real-time monitoring of the bacteria binding/ adhesion in a flowing condition was investigated by measuring the spectral shift in the resonance wavelength. The coated LPFG platform was further functionalized with covalently immobilized bacteria antibody for specific bacterial detection with a concentration as low as 104 CFU/ml. Comparing with the widely used biosensors based on surface plasmon resonance (SPR), no moving part or metal deposition is required in our biosensor, making it highly sensitive, accurate, compact and cost effective.

Salicylic Acid (SA) is a phyto-hormone involved in the regulation of induced plant defense mechanisms, primarily against biotic stresses. Various methods have been reported for detecting SA. The electrochemical methods offer economical, portable, and accurate concentration measurement of bio-chemicals like SA. Electrochemical biosensors often require modification of the working electrode (WE) with specific materials to functionalize it with bio-molecules, needed for target analyte recognition. The proposed biosensor provides a unique methodology of selectively coating the inter-digital electrodes (IDE) and further applying the method to develop a biosensor to detect SA. The electrodes are fabricated using a novel deposition process termed as, Capillary action assisted deposition (CAAD) which consists of IDEs fabricated in the form of small finger-like channels connected to a wider main channel. The drop-casted sample automatically flows from the main channel into the fine fingers under the effect of capillary action. The sensor includes a 3-electrode system arranged in a 3-D geometry, forming an integrated microfluidic channel for analyte solution flow. The WE is selectively coated with, first, Graphene oxide (GO) and next, the bi-enzyme Salicylate Hydroxylase (SH) and Tyrosinase (TYR) recipe using the proposed CAAD process. The bi-enzyme exhibits selectivity towards SA and the proposed sensor shows the detection range of 0.5 μ𝑀 to 64 μ𝑀. The electrochemical reactions are characterized by Chrono-amperometry (CA) and shows the sensitivity of 34.4 μA cm^-2 per decade change in SA concentration (in μ𝑀). To the best of our knowledge, the proposed bi-enzyme system in a microfluidic device for SA sensing is the first of its kind.

Surface-enhanced Raman scattering (SERS) integrates high levels of sensitivity and spectroscopic precision with tremendous potential for chemical and biomolecular sensing. On the other hand, metal nanoparticles have been employed in catalysis with great promise for future energy technologies. Interactions between oxygen and gold surfaces are of fundamental importance in catalysis and other multiple and diverse areas of science and technology. We propose to synergistically integrate the two aspects of metal nanoparticles in dual-functional Ag@Au core-shell nanostructures to take advantage of high SERS enhancement factor of Ag and unique catalytic property of Au. Pure Au nanoparticles with specific size are also prepared to be a comparison with Ag@Au core-shell structures in terms of SERS enhancement and catalytic properties by in situ Raman detection during the decomposition of hydrogen peroxide.

Chip-scale chemical sensors were demonstrated using flexible mid-Infrared (mid-IR) photonic circuits consisting of aluminum nitride (AlN) waveguides on ultrathin substrates. The AlN waveguide structure was fabricated by the complementary metal–oxide–semiconductor (CMOS) process. The waveguide sensor is highly bendable because the thin device thickness, which effectively reduces the surface strain. Through spectrum scanning over the characteristic -OH absorption, the waveguide sensor can differentiate methanol, ethanol, and water, and accurately determine the chemical compositions of the water/ethanol mixtures. Real-time chemical monitoring was accomplished by measuring the waveguide mode attenuation at λ = 2.65 μm. Due to the high mechanical flexibility and mid-IR transparency, the AlN chemical sensor enables integrated photonics for biomedical wearables and remote environmental monitoring.

Human skeletal muscles may undergo qualitative and quantitative, physiological and pathological changes during life. Some of these changes may be detected with imaging techniques, others with immunohystochemical and molecular analysis. Both these types of investigation are expensive, time consuming, and not readily available. Therefore, at present, a cheap, reliable, and widely applicable technique for non-invasive in vivo analysis of human muscles is lacking. Here we propose optical spectroscopy as a tool that can be added to clinical investigation without significant cost and time penalties. Recent advances in materials and fabrication techniques provided portable, performant, sensing optical spectrometers readily operated by user-friendly cabled or wireless systems. Such systems allow rapid, non-invasive and not destructive quantitative analysis of human tissues. In this investigation, we tested whether infrared spectroscopy techniques, currently utilized in many areas as primary/secondary raw materials sector, cultural heritage, agricultural/food industry, environmental remote and proximal sensing, pharmaceutical industry, etc., could be applied in living humans to categorize muscles. We acquired muscles reflectance spectra in the Vis-SWIR regions (350-2500 nm), utilizing an ASD FieldSpec 4™ Standard-Res Spectroradiometer with a spectral sampling capability of 1.4 nm at 350- 1000 nm and 1.1 nm at 1001-2500 nm. Spectra were collected from the upper limb muscles (i.e. biceps, a forearm flexor, and triceps, a forearm extensor) placed in fixed limb postures (elbow angle approximately 90°) of 22 healthy subjects (age 25-89 years, 11 females). Spectra off-line analysis included preliminary pre-processing for signal scattering reduction, Principal Component Analysis (PCA) aimed to spectral grouping and Partial Least-Squares Discriminant Analysis (PLS-DA) for implementing discrimination/prediction models. Spectral data were correlated with anthropometric variables. Optical spectroscopy proved effective for studying human muscles in vivo. Vis-SWIR spectra acquired from the arm detect muscles from other tissues, and distinguished flexors from extensors.

This paper presents a detailed synthesis of modeling and simulations results of a distributed Brillouin sensor using a newly developed algorithm. The behaviors of the backscattered Brillouin and Rayleigh signals in the optical fibers are studied. Various magnitudes of temporal and strain in the presence of coherent Rayleigh noise are performed and compared with the published experimental results. A model establishing the temporal and strain dependence on scattering coefficients have been developed and discussed in this paper. All developed simulation models illustrate outstanding precision vis-à-vis published measurement results. The work carried out in this paper cemented approach for a more complex distributed Brillouin scattering modeling.

Integrated optical Mach-Zehnder interferometer (IO-MZI) had been widely researched for biochemical and biosensing applications. However, fabrication constraints and flexibility requirements hinder the success rate of IO-MZI to be used as a commercial sensor. In this work, an innovative sol-gel processed channel waveguide has been researched, analyzed and formulated for an optimized fabrication. The relationship between the physical channel design, refractive index of channel waveguide with the surface intensity had been thoroughly investigated to form a streamlined model. Apart from that, beam polarization and wavelength influence due to the evanescent field of sol-gel channel waveguide is also simulated to further estimate the channel waveguide behavior in an optical setting. The proposed sol-gel processed channel waveguide has the advantage of high transmittance, easy-forming, excellent thermal stability and highly tunable refractive index.

This paper presents an experimental investigation of a triple lasing wavelength of fiber laser employing bidirectional SOA incorporated with a tapered fiber which operates in the L-band region. This ring configuration comprises of a bidirectional semiconductor optical amplifier and a tapered fiber. Based on the results, a single mode tapered fiber in the configuration has the ability to enhance the wavelength performance in terms of the optical signal to noise ratio and its stability. This tapered optical fiber has a diameter waist of 12 μm, length waist of 10 mm and 5 mm for its uptaper length and downtaper length. Semiconductor optical amplifier injected current varies for 130 mA, 210 mA, and 300 mA to observe fiber laser performance in term of average output power and optical signal to noise ratio. This fiber laser can lase three wavelengths at 1576 nm, 1586 nm and 1596 nm. These triple wavelengths output exhibits an excellent performance by having the average optical signal to noise ratio of 44 dB, and average peak power is -13 dbm. Furthermore, fiber laser employing bidirectional SOA incorporated with a tapered fiber has efficient performance lasing wavelength stability over 60 minutes.

The proximal interphalangeal joint (PIP) is the most important joint of the finger and is one of the most common joints to be affected by hand osteoarthritis (OA) due to excessive usage of the hand. PIP injury which may lead to osteoarthritis occurs when the protective cartilage on the boundaries of the joint begins to wear off or simply by a hyperextension of the joint. Currently, in order to diagnose joint deformity of the hand OA, particular imaging modalities namely the X-ray scanning and magnetic resonance imaging (MRI) is used but has its limitations such as radiation concerns and can be quite expensive. In this work, a fringe projection profilometry system which comprises of an LCD projector, CCD camera, and a personal computer has been developed to analyze surface changes of the PIP joint. The central concept of this optical metrology system is to apply structured light as imaging source for surface change detection. The imaging source utilizes fringe patterns generated by C++ programming and is shifted using the 3 steps 2 shift method for obtaining the phase map image. Grayscale analysis and pixel tracing were applied to detect the deformation of the PIP joint on a live individual. The result has demonstrated a successful method of PIP joint deformation detection based on the pixel tracking differences of a static and deformed state of the PIP joint.

Breast cancer is one of the fatal diseases and is one of the leading causes of death among women. Early screening for breast cancer is highly needed among women. Monitoring of the disease is also extremely vital for determining the best possible method of treatment. One of the most common symptoms of breast cancer is the breast surface change caused by the tumor within the breast. Shapes of the tumor vary among the patients, and some of the standard shapes of the tumor are round, oval, irregular, spiculated and microlobulated. Current common imaging modalities of diagnosing for breast tumor is the Magnetic Resonance Imaging (MRI), ultrasound and mammography. The current imaging modalities have been known to diagnose the disease but also has its limitations due to exposure concerns. In this work, the changes of breast surface are analyzed using a proposed fringe projection imaging modality. Surface changes of the breast were analyzed with the presence of a round shape tumor varied from 0.5 cm to 2 cm. The fringe projection profilometry system has successfully demonstrated its ability in detecting the pixel coordinate changes of the breast surface caused by the size variation of the tumor.

In this paper, cadmium sulfide (CdS) light emitting diodes (LED) die performance based on different structures configuration are simulated and investigated. The CdS LED extensively play an essential role in many applications, especially for the light sensor. The CdS LED die involves in this study are 10 μm height cylindrical circular, 9μm height dome-shaped, 10 μm height dome-shaped and 11 μm height dome-shaped structures. Increasing the height of the dome slightly changes the doping concentration and its ratio. Changes in the ratio of p-type and n-type affect the process recombination of electrons and holes. Thus, this produce high emission rate and optimum biased voltage. For the 10 μm height cylindrical circular structure, the threshold voltage of 1.95 V is recorded. Meanwhile, the 9μm height of domeshaped, 10μm height of dome-shaped and 11μm height of dome-shaped, the minimum voltage required to turn on the devices are 1.95 V, 1.96 V, and 1.975 V, respectively. It was found that dome-shaped with 11μm height generated the highest total emission rate for LED efficiency compared to other structures.