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We proposed a passive water transfer/retention system for a device such as a sensor electrode for long-term functionality. This design aims to provide water to a device/material in order to keep the device/material in a wet condition for a long time using a small amount of water in the reservoir. Our design does not need any active sensor, pump, or valve to control the water refilling. This design can be used for the application such as on-site monitoring of the soil nutrients.

Eukaryotes have evolved a specific strategy to package DNA. The nucleosome is a 147-base-pair DNA segment wrapped around histone core proteins that plays important roles regulating DNA-dependent biosynthesis and gene expression. Chromatin remodeling complexes (RSC, Remodel the Structure of Chromatin) hydrolyze ATP to perturb DNA-histone contacts, leading to nucleosome sliding and ejection. Here, we utilized tethered particle motion (TPM) experiments to investigate the mechanism of RSC-mediated nucleosome remodeling in detail. We observed ATP-dependent RSC-mediated DNA looping and nucleosome ejection along individual mononucleosomes and dinucleosomes. We found that nucleosome assembly protein 1 (Nap1) enhanced RSC-mediated nucleosome ejection in a two-step disassembly manner from dinucleosomes but not from mononucleosomes. Based on this work, we provide an entire reaction scheme for the RSC-mediated nucleosome remodeling process that includes DNA looping, nucleosome ejection, the influence of adjacent nucleosomes, and the coordinated action between Nap1 and RSC.

There have been various challenges associated with inventory management for supermarkets. These includes labor intensive stock taking procedures and mismatching of goods in retail store as compared to system record. These challenges will eventually result in the loss of sale for the company. In order to address the mismatching of goods and labor intensive issue, there is a need for real-time monitoring of the goods on the retail shelves. These will reduce the needs for manual stock taking, improve the efficiency in goods replenishment and thus resulting in overall sale profit. In this work, $8 \times 8$ pressure sensing array substrate with wireless module readout and tablet application has been developed as a demonstration prototype for monitoring the weight of goods on the shelve. The sensing system achieved a average repeatability error of 5.3% for a force range of 0.2N to 10.2N via bench-top charcaterisation setup. System firmware algorthim has been validated with a data error of less than 3% as compared to theoretical calculation.

Hypertension, in other words called high blood pressure, is a chronic and serious medical condition that considerably increases the risks of other ailments associated with the heart, brain, and kidney. Minimally invasive catheter-based renal denervation procedure is an effective way to treat hypertension for patients whose blood pressure level was unable to be brought under control by medication. However, for such systems an accurate temperature monitoring system is required to control the ablation power for a successful procedure and to avoid unwanted tissue damage. In this paper, the development of a platinum-based resistance temperature detector is presented. The temperature sensor is modeled using finite element analysis simulation and realized by silicon microfabrication. To ensure the performance of each fabricated sensor die, the test and characterization methodology of the sensor is translated and carried out using fully automatic test equipment. In this work, we are able to achieve a relatively large change in resistance of more than 15% with respect to the temperature change from 20 °C to 85 °C. Platinum as sensor material provided a linear relationship between change in resistance and temperature. This biocompatible resistance temperature detector sensor with its linear and consistent performance will allow us to accurately monitor the temperature in the renal denervation application.

Monitoring and recording of electroencephalogram (EEG) is a non-invasive procedure that is increasingly used in neuromonitoring. Patient management is assessed and tailored based on the acquired brain signals that indicates the neurological state of the patient. Conventional EEG systems are wet systems. EEG recording in itself is not painful, but scalp preparation for the electrode attachment and washing afterwards may be uncomfortable. In this paper, a soft flexible gel-free dry electroencephalogram (EEG) electrodes and dry EEG head cap is developed and proposed. The dry EEG electrodes is a hybrid packaging rigid metal snap connectors, soft and flexible polymer material, and Silver-Silver Chloride (Ag- AgCl) coating. The sensor body/ structure does not use conductive polymer and there is no peeling off of the structure that could lead to concern in signal degradation. The dry EEG head cap is a fully-adjustable one-piece stretchable material integrated with reference and ground electrodes. Impedance reading of wet system is

Chronic ulcer such as venous leg ulcer (VLU) required an extensive healing process. It has a high recurrence rate where 33% of the recovered patients will relapse. Current treatment for VLU include compression therapy using compression bandage and stocking. Skill professional are required to apply the compression bandage therapy. An optimum compression pressure between 35mmHg and 45mmHg will aid in the healing of the VLU. Micro environment with an increase of 1.5-degree Celsius to 2.2-degree Celsius indicate an inflammation onset. Through monitoring the pressure applied onto the patient’s leg and temperature of the wound site, it would help in the overall wound management and improve healing. In this work, an integrated pressure sensing strips with 24 pressure sensing elements and temperature sensors was developed to monitor of compression pressure and temperature of the wound sites. Bench-top characterization result shows that the proposed device is able to operate within the required optimum pressure range with a repeatability of less than 3.5%. The proposed device is able to detect temperature range within 28-degree Celsius to 40-degree Celsius with ADC value of 12/ degree Celsius.

Extravasation is a complication of intravenous (IV) cannulation in which vesicant drugs leak from a vein into the surrounding subcutaneous tissue. The severity of extravasation depends on the type, concentration, and volume of drugs that accumulate in the subcutaneous tissue. Rapid detection of extravasation can facilitate prompt medical intervention, minimizing tissue damage, and preventing adverse events. In this study, we present two portable sensor patches, namely gold- and carbon-based sensing patches, for early detection of extravasation. The gold-based sensor patch detected extravasated fluid of volume as low as 2 mL in in vivo animal models and human clinical trials; the patch exhibited a resistance change of 41%. The carbon-based sensor patch exhibited a resistance change of 51% for 2 mL of extravasated fluid, and fabrication throughput and cost-effectiveness are superior for this patch compared with the gold-based sensing patch.

In this paper, we shall discuss the suitable alternative material to gold for creating traces or electrodes of a noninvasive flexible sensor patch that is used for detecting early extravasation during intravenous cannulation. The samples were prepared by printing $5 \mu \mathrm{m} -$ to $10 \mu \mathrm{m} -$ thin piezoresistive polymer-based Carbon paste on a base polymer patch, also called the adhesive film. The first samples have the traces embedded in between two base adhesive films. The sensitivity of the samples was characterized by using a pressure chamber/jig with 4 cm hole to mimic an extravasation by bump formation when pumped with compressed dry air (CDA) that is connected to a 15 psi source. The sensitivity value obtained was 20% up to 23% at 0.16 psi. After optimization of the curing temperature of the adhesive film and piezoresistive polymer-based Carbon traces, ex-vivo test was conducted with the prototype sample placed on the cannulation site of a pork front hock. At 2 ml and 5 ml infused fluid, the sensitivity obtained is only 1.1% and 2.44%, respectively. The overall prototype dimension of all samples is 6 × 7 cm2. The second samples were prepared with narrower trace width and spacing than the first samples. Sensitivity obtained from the second sample at 0.16 psi increased to 50% up to 79%. The third samples were prepared with the same narrow trace with as the second sample, but this time the piezoresistive polymer-based traces were not embedded in two adhesive films, making the sample a single layer patch only. Sensitivity obtained at 0.16 psi increased further to 140% up to 200%. The 0.16 psi readout is based on previous data that at this pressure induced in the 4 mm hole where the adhesive film is placed over, it translates to 3mm bump height at 2ml infused volume on the skin. The results suggest a strong potential in the development of the piezoresistive polymer-based Carbon traces for flexible non-invasive sensor patch for early extravasation detection.

Renal denervation procedure has been developed as a potential treatment for resistance hypertension or treatment-resistant hypertension. Renal denervation catheter was employed as a surgical tool to ablate the renal nerve with radio frequency (RF) pulses or ultrasound energy. Ensuring the proper contact of the electrical heater on the artery wall is critical, as excessive force or pressure could damage the artery wall. Non-contact ablation would not be able to perform the denervation operation effectively. The electrode size, overall packaging size and stiffness need to be calculated and analyzed to achieve the design for manufacturability (DFM). Ansys static structural system was used to optimize the design, the results shows that for the mini electrode with overall size of 0.6mm × 1.8 mm × 0.2 mm, 1.0mm deformation with 0.226MPa stress has a safety factor of 5 is recommended. The detailed chip level simulation shows that the force sensor chip with 150um bump has better sensitivity.

Renal denervation procedure had been emerging as a potential treatment for resistant hypertension condition. It is a minimally invasive procedure where radiofrequency (RF) energy is supplied to ablate and deactivate the renal artery nerve. The deactivation of the renal nerve helps to reduce and control the patient’s blood pressure level. In order to achieve multiple ablation sites per ablation cycle, multiple discrete RF electrodes and temperature sensors components are required for integration with ablation catheter. This is a tedious and time consuming process. To address this issue, this paper proposed a three dimensional roll-up polymer-silicon structure with an overall thickness of 110um for easy of assembly. This roll-up structure with a ‘belt’ slot feature will be used for assembling of MEMS based sensor chip into a single component. Bench-top mechanical testing to simulate the activation and de-activation of the catheter had been performed. The roll-up structure was able to achieve a smooth activation of 5° to 62° with a maximum length of 8mm (diameter) for 10 repeated cycles.

In this work, we present a flexible printed multi-functional sensor platform for medical applications. The device consists of printed temperature and force elements on a flexible printed circuit board (FPCB). The thickness, curing temperatures and encapsulating epoxies are optimized for the individual inks and the device is assembled and tested on the benchtop. Force measurements against impedance and temperature measurements against impedance were then conducted and discussed. The performance of both sensors were then characterized.

Hypertension is a growing worldwide issue. Patients whom blood pressure level were unable to be brought under control despite the usage of three or more medication is known as resistant hypertension. Resistant hypertension increased the risk of patients developing adverse cardiovascular disease as compared to patients with controlled high blood pressure. The current treatment for resistant hypertension includes minimally invasive catheter based renal denervation procedure. However, there is no procedural endpoint of the ablation of the renal nerve for this renal denervation procedure. In this work, an integrated thermistor sensor with a heating electrode was developed for monitoring of the ablation temperature during the procedure. Thus ensuring proper ablation of the nerve, reducing the risk of damaging the renal nerve and increasing the success rate of the procedure. Bench-top characterization on thermistor resistance output with respect to temperature change and ex-vivo testing on RF ablation using the integrated sensor were performed. Testing result were presented in the paper. An average of 15kohm resistance change (?R) in thermistor sensing element from temperature range of 25oC to 90oC. For RF power of 1 W, the ablation scarring size on the tissue was approximately 2mm (length and width) with a depth of 2.5mm depth.

In this work, a novel hermetic packaging method using titanium and ceramic casing is proposed for long term implantable medical device. The proposed titanium-ceramic casing for implants has a better radio frequency (RF) transparency advantage as comparison to metallic materials. The proposed hermetic packaging method is used to integrate a high channels neural probe array and an active circuit module through a high density flexible cable without feedthrough integration. Hence, the profile of the integrated device achieved is as low as three millimeter and it is placed in the subdermal space. To evaluate the hermeticity of the device packaging, a helium gas leakage test was conducted and discussed. In vitro cytotoxicity test was also performed and evaluated.

Wearable electroencephalography (EEG) system can be worn for prolonged periods and have been widely used to reduce susceptibility to artifacts. It can improve localization of epileptic foci, and help doctors to optimize the treatment for patients to control epileptic seizures effectively. Commercial metal-based dry EEG sensors are capable of providing signal acquisition, however it is uncomfortable for patients since the sensor's material property is too hard to wear. In this study, design and fabrication process of dry EEG sensor are proposed for epilepsy monitoring. A medical grade silicone, Polydimethylsiloxane (PDMS), was molded as deformable substrate of the sensor. Virtual prototyping was created and simulated by ANSYS mechanical structural module. Force measurement of the fabricated sensor was conducted and discussed. The actual and simulated of sensor's stiffness were characterized and discussed.

A fully integrated SoC for multimodality intracranial neuromonitoring is presented in this paper. Three sensors including a capacitive MEMS pressure sensor, an electrochemical oxygen sensor and a solid-state temperature sensor are integrated together in a single chip with their respective interface circuits. Chopper stabilization and dynamic element matching techniques are applied in sensor interface circuits to reduce circuit noise and offset. On-chip calibration is implemented for each sensor to compensate process variations. Measured sensitivity of the pressure, oxygen, and temperature sensors are 18.6 aF/mmHg, 194 pA/mmHg, and 2 mV/°C, respectively. Implemented in 0.18 m CMOS, the SoC occupies an area of 1.4 mm × 4 mm and consumes 166 μW DC power. A prototype catheter for intracranial pressure (ICP) monitoring has been implemented and the performance has been verified with ex vivo experiment. ASTAR (Agency for Sci., Tech. and Research, S’pore)

This study tries to investigate the performance of specific stylized mutual funds focusing on the matched professional abilities of fund managers, based upon their relative educational backgrounds. Using a 2001–2011 dataset on 1164 fund managers investing in the Taiwan Stock Exchange comprising mainly of high-tech stocks, our findings suggest that mutual fund managers with joint science and engineering (SE) and business management (BM) backgrounds perform significantly better than fund managers only with business management (BM) background when managing high-tech funds. These results also provide support for the notion that the proliferation of joint degree programs across the associated fields lends credence to the belief that synergies exist between the backgrounds in the stylized mutual funds with professional's educational background of fund manager matching with stock targets.

Intravenous cannulation (IV) has a potential medical complication known as extravasation which arise when the fluid accumulates in the subcutaneous tissue layer causing skin swelling symptom. The cost incurred for the addition hospitalization stay and treatment due to the extravasation complication is high. The current detection devices for extravasation is expensive, bulky and it is not suitable for the daily routine IV cannulation administration. In this work, a wearable and conformal sensor patch was developed for detection of skin swelling and tension. Structural simulation analysis and ex-vivo characterization of thin film metal (Ti/Cu/Au: 20 nm/ 2 µm /20 nm) were performed and result were presented in the paper. The sensor patch was able to detect skin tension and swelling of less than 3mm deformation height caused by 2-ml of fluid infusion. The sensitivity of the electrode sensor was 45% change of resistance per ml volume of infused solution.

The biopackaging of a minimally invasive sonothrombolysis device (ultrasound-assisted clot lysis device) for acute stroke treatment is proposed and presented. Instead of using thrombolytic medicine (tissue plasminogen activators) in combination with the ultrasound wave for total blood clot dissolution, the proposed sonothrombolysis device uses only pure ultrasound wave generated from Microelectromechanical Systems (MEMS)-based piezoelectric micromachined ultrasonic transducers (pMUTs) that were designed and fabricated in-house. The proposed biopackaging aims to simplify and shorten the clot lysis procedure which could help speed up the recanalization or surgical removal of the blood clots in acute ischemic stroke treatment. The device packaging is composed of two main integrated parts – the three-dimensional (3D) printed United States Pharmacopeia (USP) Class VI plastic material and the 50-µm thin polyimide flexible printed circuit board (PI FPCB) substrate. The 3D printed USP Class VI plastic material is configured as the drainage catheter of the dissolved clots as well as the custom-fit carrier of the PI FPCB substrate that is coupled and secured onto it. A single layer PI FPCB is used as the substrate of either two or four number of MEMS-based pMUTs, which are attached on it using biocompatible epoxy and wire bonded using 1 mil gold wire. The PI FPCB is also designed such that it is directly compatible with the Flat Flex Cable (FFC) connector of the external circuitry that would trigger the MEMS-based pMUTs to generate acoustic signals as well as measure the viscosity of the blood clot. To drain the dissolved blood clots, the catheter is printed with a number of holes are placed across and around the pMUT location. The catheter tip is rounded-off to remove sharp corners from the plastic material. Buckling analysis is done to simulate stiffness of the catheter when inserted into the brain tissue leading to the center of blood clot. The buckling load of the 3D printed USP Class VI plastic material at a total deformation of 0 – 1 mm at 1 sec is 2038.4N as compared to the buckling load of the silicone rubber (usual catheter material, without the metal guiding rod) which is only 0.128N. The simulation results showed that the 3D printed USP Class VI plastic material will not buckle easily during penetration in the brain tissues or insertion into the blood clot compared to silicone rubber. In order to validate that the combination of materials used in sonothrombolysis device are non-reactive and are not cytotoxic, in vitro cytotoxicity test based on ISO 10993-5 standards is performed. The materials passed.

Patients with paralysis, spinal cord injury, or amputated limbs could benefit from using brain&ndash, machine interface technology for communication and neurorehabilitation. In this study, a 32-channel three-dimensional (3D) multielectrode probe array was developed for the neural interface system of a brain&ndash, machine interface to monitor neural activity. A novel microassembly technique involving lead transfer was used to prevent misalignment in the bonding plane during the orthogonal assembly of the 3D multielectrode probe array. Standard microassembly and biopackaging processes were utilized to implement the proposed lead transfer technique. The maximum profile of the integrated 3D neural device was set to 0.50 mm above the pia mater to reduce trauma to brain cells. Benchtop tests characterized the electrical impedance of the neural device. A characterization test revealed that the impedance of the 3D multielectrode probe array was on average approximately 0.55 M&Omega, at a frequency of 1 KHz. Moreover, in vitro cytotoxicity tests verified the biocompatibility of the device. Subsequently, 3D multielectrode probe arrays were implanted in rats and exhibited the capability to record local field potentials and spike signals.

This work presents a silicon-based multichannel probe integrated with a front end low power neural recording integrated circuit (IC) which is used in acute neural recording application. The low power neural recording IC contains 100-channel analog recording front-ends, 10 multiplexing successive approximation register ADCs, digital control modules and power management circuits. The 100-channel neural recording IC consumes 1.16-mW, making it the optimum solution for multi-channel neural recording systems. The neural recording IC and Si probe are integrated in a printed circuit board (PCB) which is fixed on the skull using dental resin. Digital neural signal is converted to analog signal and output by neural recording IC. The signal-to-noise ratio of neural recording signal can be increased through the reduction of interconnect length. The buckling strength of the fabricated probes was simulated using finite element analysis and measured by compression tester. The packaging method of 2D probe and neural recording IC was successfully demonstrated. The impedance of the assembled probe is also measured and discussed. To verify the functionality of Si probe integrated with neural recording IC, a pseudo neural signal acquisitions have been perform.

This work evaluated the biocompatibility and the bio-degradability/bio-solubility by comparing different bio-soluble glass materials for neural probe applications. Diboron trioxide and phosphorus oxide based bio-soluble glass materials are used as probe substrate. Two experiments conducted will be discussed in this paper. The first experiment is preliminary bench test to study the dissolution rate of the samples. Second experiment is an in vivo experiment to further investigate the dissolution rate and the biocompatibility of the material. According to the experimental results, higher content (how high?) of diboron trioxide glass has a shorter dissolution period (how long?) and evoke less inflammatory response compared to a sample with lower content of diboron trioxide and phosphorus oxide based glass. Phosphorus oxide based glass which produces an acidic medium resulting in advance inflammatory response is not suitable as base substrate material for neural probe application.

Neural probe array is utilized in neural recording, in the aim to understand the neural activity. Silicon is the common substrate used in neural probe array. However, due to the rigid nature, the silicon-based neural probe array causes cell damage during implantation into the brain tissue. This would reduce the signal-to-noise ratio. Therefore, flexible polymer probe is more suitable as it can help to minimize the tissue damage and thus increasing the signal-to-noise ratio. The lack of stiffness for the flexible probe is solved by coating it with polyethylene glycol (PEG). It stiffens the probe and can be dissolved in water, which allows the polymer probe to regain its flexibility. The proposed integrated probe with reduced distance between probe and ASIC will further help to improve the signal-to-noise ratio during neural recording. The coated flexible probe regained original impedance of 14.1 kΩ at a frequency of 1 kHz. A bench-top neural recording with the flexible probe array in saline solution will also be acquired.

This paper presents a fully implantable 100-channel neural interface IC for neural activity monitoring. It contains 100-channel analog recording front-ends, 10 multiplexing successive approximation register ADCs, digital control modules and power management circuits. A dual sample-and-hold architecture is proposed, which extends the sampling time of the ADC and reduces the average power per channel by more than 50% compared to the conventional multiplexing neural recording system. A neural amplifier (NA) with current-reuse technique and weak inversion operation is demonstrated, consuming 800 nA under 1-V supply while achieving an input-referred noise of 4.0 μVrms in a 8-kHz bandwidth and a NEF of 1.9 for the whole analog recording chain. The measured frequency response of the analog front-end has a high-pass cutoff frequency from sub-1 Hz to 248 Hz and a low-pass cutoff frequency from 432 Hz to 5.1 kHz, which can be configured to record neural spikes and local field potentials simultaneously or separately. The whole system was fabricated in a 0.18-μm standard CMOS process and operates under 1 V for analog blocks and ADC, and 1.8 V for digital modules. The number of active recording channels is programmable and the digital output data rate changes accordingly, leading to high system power efficiency. The overall 100-channel interface IC consumes 1.16-mW total power, making it the optimum solution for multi-channel neural recording systems. ASTAR (Agency for Sci., Tech. and Research, S’pore) Accepted version

This work presents a bio-degradable glass probes and its biocompatibility assessment for neural applications. The probes can be implanted into different sites of the human brain for recording and stimulating purposes. Current existing neural probe address the probe stiffness requirement for the penetration of brain tissue. However, this requirement normally resulted in the rigidity of the probe which is non-compatible with the brain tissue movement for long term implantation. The brain neuron cells will be damaged by too rigid probe substrate. In order to address this issue, bio-degradable glass probes having sufficient stiffness for a smooth brain insertion as well as ability to degrade after implantation; leaving behind the flexible circuitry substrate was being explored. The biodegradability of the proposed probe was evaluated.

This paper describes the integration of micro-electro-mechanical systems (MEMS) tri-axial force sensor using polyimide-based substrate for sensorised guide wire application. For tri-axial force sensor, piezoresistive silicon nanowires (SiNWs) are embedded into a cross cantilever design with a maneuverable stylus to allow the detection of force in all directions, and amplify the tactile forces at the tip for transverse directions. The electrical resistance changes in the four SiNWs are used to decode an arbitrary force applied onto the force sensor. Robustness of the force sensor is improved due to the novel design by incorporating a mechanical stopper at the tip of the stylus. Flip chip bonding using gold stud bumps is used to mount the force sensor on a substrate for characterization and to simplify the assembly process. The packaging process of the miniaturized sensorised guide wire was presented in this work.

This work presents a three-dimensional flexible polyimide (PI) probe array with biodegradable polymer that offers desirable insertion capability. In order to avoid the recording sites position shifts slightly and damage neuron cells when the body moves, the flexible neural probes are more preferable than traditional Si-based neural probes. A sufficient buckling strength of flexible probe is critical for inserting flexible probe into the brain. Here, we used a biodegradable polymer, polyethylene glycol (PEG), to improve the mechanical stiffness of flexible probe. PEG, which is solid state at room temperature and dissolves when immersing in water, was coated onto the flexible probe and the mechanical stiffness of the flexible probe was increased before insertion into the biological tissue. The buckling strength of different probes was simulated using finite element analysis and measured by compression tester. The coated PEG flexible probe maintains sufficient stiffness to facilitate tissue penetration with solid PEG elastic modulus of 660±19 MPa but loses its strength within 25 minutes once immersed in saline. A microassembly method of three-dimensional flexible probe array was also proposed to integrate the flexible probe and their interconnections. In vitro test, the coated PEG flexible probe regained their original impedance of 12.8 kΩ at 1 kHz within 30 minutes of immersing in saline via water absorption and polymer’s biodegradable response.

BUD23 in Saccharomyces cerevisiae encodes for a class I methyltransferase, and deletion of the gene results in slow growth and random budding phenotypes. Herein, two BUD23 mutants defective in methyltransferase activity were generated to investigate whether the phenotypes of the null mutant might be correlated with a loss in enzymatic activity. Expression at the physiological level of both D77A and G57R mutants was able to rescue the phenotypes of the bud23-null mutant. The result implied that the methyltransferase activity of the protein was not necessary for supporting normal growth and bud site selection of the cells. High-level expression of Bud23 (G57R), but not Bud23 or Bud23 (D77A), in BUD23 deletion cells failed to complement these phenotypes. However, just like Bud23, Bud23 (G57R) was localized in a DAPI-poor region in the nucleus. Distinct behaviour in Bud23 (G57R) could not be originated from a mislocalization of the protein. Over-expression of Bud23 (G57R) in null cells also produced changes in actin organization and additional septin mutant-like phenotypes. Therefore, the absence of Bud23, Bud23 (G57R) at a high level might affect the cell division of yeast cells through an as yet unidentified mechanism. Copyright © 2012 John Wiley & Sons, Ltd.

Intravenous (IV) cannulation is a routine procedure for hospital patients for drug or fluid administration. Successful delivery of drugs and fluids depends on the cannula remaining in the vein at all times. Extravasation is a complication of IV cannulation and refers to the accidental leakage of drugs or fluids from the vein to the surrounding tissues when the IV cannula moves out of the vein. The incidence of extravasation in neonates is up to 15%. Extravasation is frequently detected late when a large subcutaneous "bump" or swelling is noticed at the IV cannula site indicating a large amount of infused fluid has tissued. The severity depends on the volume/ type of drug extravasated and the time lapse before extravasation is detected. It is important to detect extravasation early to ensure that the drugs/ fluids administered will reach the patient's intravascular space otherwise it can jeopardize medical management and compromise patient care. In this work, we present a portable, practical and cost-effective sensor which can be universally applied to all patients to prevent the extravasations injuries.

In this work, we present the biopackaging andintegration method of an intracranial pressure microsystemfor multimodal neural monitoring. The neural monitoring chipused is a System-on-Chip (SoC) which hasMicroelectromechanical Systems (MEMS) capacitive pressuresensor that is fabricated in-house after Complementary Metal-Oxide Semiconductor (CMOS) wafer fabrication process, witha temperature sensor and an oxygen sensor in order to achievemultimodal neural monitoring functions. Polyimide is used forthe substrate of the SoC die and passive component due to itsbiocompatibility and flexibility. A reversed stand-off stitchwire bonding process was employed in order to achieve a lowprofilewire looping for the interconnection of the SoC die tothe substrate. The biocompatible coatings of this implantablesystem consist of Parylene-C (for covering temperature andpressure sensors), Nafion® (for covering oxygen sensor), andmedical grade silicone elastomer (for overall deviceencapsulation). The ICP microsystem wireless reader modulewas packaged in a customized biocompatible hermetic Teflonhousing. To reinforce and seal the catheter, which is integratedwith the microsystem, during the device implantation into thebrain tissue, it is filled until the wire bonded portion withpolydimethylsiloxane. Similarly, the guiding tip of the catheterwhich will facilitate the sensor device to penetrate into thebrain tissue is made and casted from a specially designed moldusing polydimethylsiloxane as the material. Verification of thepackaging feasibility was measured by measuring thesensitivities of the pressure sensor, oxygen sensor, andtemperature sensor. The whole microsystem also passed theISO 10993-5 standards in vitro cytotoxicity test with aconclusion of no reactivity and no cell lysis cell growth in cellculture, verifying its biocompatibility

Revascularization procedure for peripheral arterydisease is dependent on surgeon's skill and experience for asuccessful procedure. An integrated sensor on guidewire isproposed to reduce such dependency during the procedure. The development and packaging of the sensor with a hybridsilicone-polymer substrate (HSPS) and a silicon stopper arepresented in this paper. A compact HSPS (0.4mm x 10mm x0.31mm) with trace width/spacing of 20µm/20µm for fiveoutput signals and Si stopper with safety displacement featureto prevent force overloading are fabricated. It is able toenhanced current sensor integrated guidewire by improvingthe robustness and provides a forward sensing mechanism(orthogonal assembly). The assembled device is able tomeasure up till 42mN force with a resolution of 0.2mN. Detailof characterization testing and result will be presented in the paper.

As Machine-Type-Communications (MTC) continues to burgeon rapidly, a comprehensive study on overload control approach to manage the data and signaling traffic from massive MTC devices is required. In this work, we study the problem of RACH overload, survey several types of RAN-level contention resolution methods, and introduce the current development of CN (core network) overload mechanisms in 3GPP LTE. Additionally, we simulate and compare different methods and offer further observations on the solution design.

In this work, we present an ultra-slim profile packaging and assembly solution of a 360-μm diameter medical guide wire fitted and integrated with silicon based fractional flow reserve (FFR) sensor. The miniaturization of the whole sensorized guide wire assembly without sacrificing its sensing functionality was made possible by the use of polyimide flexible printed circuit board (FPCB) as the substrate material for the silicon platform and by the use of lowest possible wire looping profile to create interconnection between the FFR sensor and the FPCB's bonding pads using the gold wires. In order to reinforce and protect the wire interfaces, as well as to maintain the required biocompatibility of the whole system, a thin layer of Polydimethylsiloxane (PDMS) was used for the encapsulation process. Long signal wires were then attached to the bonding pads of FPCB before finally fitted inside a miniaturized metal housing. This whole system has easily fit and integrated with the 360-μm diameter medical guide wire. In order to verify the packaging feasibility, the electrical short testing of the bonding pads and SEM observations were conducted.

Guidewire procedure for peripheral artery disease treatment is heavily dependent on the surgeon's skills and experiences. In order to reduce such dependency, sensor-enhanced forward sensing guidewire is proposed. In this paper, we proposed a silicon cap structure that increases the robustness and efficient force transfer of the existing sensor-enhanced forward sensing guidewire. Silicon cap structure of 0.32 × 0.32 × 0.40mm has been fabricated using two masks process. Assembly of silicon structure with sensor having a 30μm overloading protection limit and resistance changes of 25kΩ with applied force ranging from 0∼40mN has been demonstrated.