Wireless Power Transfer in Wearable Smart Contact Lenses [Open access]

In 2016, a smart contact lens was developed by Google company which aimed to directly implanting micro-smart lenses into the human eye to test blood sugar percentage by tears. However, small sizes implantable devices such as contact lens requires power transfer unit for continuously power supply. Thus, this project aims to design a power transfer unit with Inductively Coupled Power Transfer (ICPT) technology for smart contact lens which works under 2.45GHz to power an LED at load. The coil size is designed as 10mm inner diameter, 12mm outer diameter and 0.2mm wire width. Additionally, polydimethylsiloxane (PDMS) is used as the contact lens substrate. During the simulation, different eye models were built since the coil needs to be warped on top of lens and the eyeball, and under different conditions the S11 parameter is adjusted to around -10dB. The antenna is fabricated by technician in school, due to the technology restriction, the antenna was fabricated with unequal line width, which causes a resonate frequency shift to 900MHz with -8dB S11 value. To power an LED at load side, full-wave and half-wave rectifiers are built separately with different component values and send to fabrication. The antenna performance was tested under three conditions, in air, on human hand, and on water surface to imitate the liquid condition in human eye, but since the dielectric constant varies in each case, and for fabrication there is an extra circuit unit which effecting the copper coil numbers, the tested resonant frequency is not as desired values

Wireless Power Transfer in Wearable Smart Contact Lenses [Open access]

In 2016, a smart contact lens was developed by Google company which aimed to directly implanting micro-smart lenses into the human eye to test blood sugar percentage by tears. However, small sizes implantable devices such as contact lens requires power transfer unit for continuously power supply. Thus, this project aims to design a power transfer unit with Inductively Coupled Power Transfer (ICPT) technology for smart contact lens which works under 2.45GHz to power an LED at load. The coil size is designed as 10mm inner diameter, 12mm outer diameter and 0.2mm wire width. Additionally, polydimethylsiloxane (PDMS) is used as the contact lens substrate. During the simulation, different eye models were built since the coil needs to be warped on top of lens and the eyeball, and under different conditions the S11 parameter is adjusted to around -10dB. The antenna is fabricated by technician in school, due to the technology restriction, the antenna was fabricated with unequal line width, which causes a resonate frequency shift to 900MHz with -8dB S11 value. To power an LED at load side, full-wave and half-wave rectifiers are built separately with different component values and send to fabrication. The antenna performance was tested under three conditions, in air, on human hand, and on water surface to imitate the liquid condition in human eye, but since the dielectric constant varies in each case, and for fabrication there is an extra circuit unit which effecting the copper coil numbers, the tested resonant frequency is not as desired values

Design and operations optimization of membrane separation for flexible carbon capture from natural gas combined cycle systems

We explore the concept of flexible carbon capture using membrane separation. Flexible carbon capture has been studied in recent years as a measure to decarbonize fossil-fired power generation in response to electricity market conditions, including varying electricity prices and/or fluctuating electricity supply requirements. The importance of flexible operation of carbon capture systems is highlighted by the increasing penetration of intermittent energy generation from renewable sources such as wind and solar PV. To accommodate the integration of renewable energy into the grid, fossil-fired power plants would need to generate varying electricity load, producing flue gas with varying characteristics and at varying volumes. Carbon capture systems in a high-renewables grid will be required to operate flexibly to respond to these changes. Flexible carbon capture has been studied for amine absorption,1-2 a leading CCS technology. This work explores the possibility of flexible carbon capture using membrane separation, a promising alternative to amine absorption. In particular, membranes are considered to be very responsive to system changes and require very short start-up times.3 In addition, membrane separation has advantages such as having a smaller footprint, being more environmentally benign (no corrosive chemicals involved in the separation process), and potentially incurring lower separation energy. In this work, we perform optimization to determine the optimal process design and time-varying operations of a polymeric membrane system separating CO2 from a natural gas combined cycle (NGCC) with wind energy integration. The total net present value (NPV) of the gas turbines and membrane system is maximized. Both design and operations of the capture plant are optimized. Design decision variables include membrane process configuration, membrane size, CO2/N2 selectivity and CO2 permeance (two key membrane properties relevant to separation performance), and compressor and vacuum pump sizes. These parameters are determined before a capture unit is built. After the plant is built, operational decision variables include gas flowrates, the pressure ratio across the membrane and permeate-side (low-pressure side) pressure. These are parameters that can be adjusted, within limits, given electricity market conditions for a given time period. Time-varying electricity output from gas turbines as well as the associated flue gas flowrate and composition will be determined by HyPPO, an in-house software developed at Stanford University for modeling and optimization of flexible and renewable-integrated power systems. HyPPO models beneficial operating strategies for a set of statistically representative days. HyPPO results will be used with membrane separation models for various process configurations as modeled in MATLAB. 1. Cohen, S. M.; Rochelle, G. T.; Webber, M. E., Optimizing post-combustion CO2 capture in response to volatile electricity prices. International Journal of Greenhouse Gas Control 2012, 8, 180–195. 2. Mac Dowell, N.; Shah, N., The multi-period optimisation of an amine-based CO2 capture process integrated with a super-critical coal-fired power station for flexible operation. Computers & Chemical Engineering 2015, 74, 169–183. 3. Brunetti, A.; Scura, F.; Barbieri, G.; Drioli, E., Membrane technologies for CO2 separation. Journal of Membrane Science 2010, 359 (1), 115–125

Flexible RFID Patch for Food Spoilage Monitoring

When food is reversed under an inappropriate situation, for example inadequate temperature, foodstuff would turn rotten as a result of the rapid breed of food spoilage bacteria under warm and wet circumstances where bacteria can be easily generated, the consequences can be worse if human beings eat those degenerative comestible, we might get bromatoxism. This paper focuses on the designing and simulation of a wearable radio frequency identification (RFID) patch for food spoilage monitoring with smart packaging that can be recognized and read temperature information by device supporting near field communication (NFC) technology through an attached circular antenna. More precisely, this patch can be read under a designed high frequency of 13.56MHz, and data is transmitted from the chip MLX90129 with its internal sensor that sends the temperature to the reader module

Effects of Deep Reductions in Energy Storage Costs on Highly Reliable Wind and Solar Electricity Systems

We use 36 years (1980–2015) of hourly weather data over the contiguous United States (CONUS) to assess the impact of low-cost energy storage on highly reliable electricity systems that use only variable renewable energy (VRE; wind and solar photovoltaics). Even assuming perfect transmission of wind and solar generation aggregated over CONUS, energy storage costs would need to decrease several hundred-fold from current costs (to ∼$1/kWh) in fully VRE electricity systems to yield highly reliable electricity without extensive curtailment of VRE generation. The role of energy storage changes from high-cost storage competing with curtailment to fill short-term gaps between VRE generation and hourly demand to near-free storage serving as seasonal storage for VRE resources. Energy storage faces “double penalties” in VRE/storage systems: with increasing capacity, (1) the additional storage is used less frequently and (2) hourly electricity costs would become less volatile, thus reducing price arbitrage opportunities for the additional storage

Exploring the Intersection of Complex Aesthetics and Generative AI for Promoting Cultural Creativity in Rural China after the Post-Pandemic Era

This paper explores using generative AI and aesthetics to promote cultural creativity in rural China amidst COVID-19's impact. Through literature reviews, case studies, surveys, and text analysis, it examines art and technology applications in rural contexts and identifies key challenges. The study finds artworks often fail to resonate locally, while reliance on external artists limits sustainability. Hence, nurturing grassroots "artist villagers" through AI is proposed. Our approach involves training machine learning on subjective aesthetics to generate culturally relevant content. Interactive AI media can also boost tourism while preserving heritage. This pioneering research puts forth original perspectives on the intersection of AI and aesthetics to invigorate rural culture. It advocates holistic integration of technology and emphasizes AI's potential as a creative enabler versus replacement. Ultimately, it lays the groundwork for further exploration of leveraging AI innovations to empower rural communities. This timely study contributes to growing interest in emerging technologies to address critical issues facing rural China.Comment: Accepted by 2023 the 1st International Conference on AI-generated Content (AIGC2023

Priming of Toll-like receptor 4 pathway in mesenchymal stem cells increases expression of B cell activating factor

AbstractMesenchymal stem cells (MSCs) can be polarized into two distinct populations, MSC1 and MSC2, by activation of different Toll-like receptors (TLRs). TLR4-primed MSC1 expressed proinflammatory factors, whereas TLR3-primed MSC2 expressed suppressive factors. However, little is known about the function of TLRs on B lymphocyte-related immune modulation. In this study, we investigated the expression of B cell activating factor (BAFF), a member of the tumor necrosis factor ligand superfamily with notable stimulating activity on B cells, in human MSCs (hMSCs) and in murine MSCs (mMSCs) after activation of TLRs. BAFF was increasingly expressed in presence of TLR4 agonist (lipopolysaccharide, LPS), while TLR2 agonist (Zymosan) and TLR3-agonist (polyinocinic–polycytidykic acid, poly I:C) had no effect on BAFF expression. In addition, we demonstrated that signaling pathways of NF-κB, p38 MAPK, and JNK were involved in TLR4-primed BAFF expression. Our results suggested that TLR4 and downstream pathways in MSCs exert an important function in B lymphocyte-related immune regulation. Further defining a homogeneous population of MSCs should provide insight into MSC-based immune-modulating therapy

Serpentine-Shaped Metamaterial Energy Harvester for Wearable and Implantable Medical Systems

Integration with the curvilinear, soft, and time-dynamic surfaces of the human body is critical for most implantable and wearable biomedical systems. Devices that can imitate the mechanics of the body provide opportunities to create human-machine interfaces. Additionally, wireless functionality is essential to monitor health/wellness, study disease conditions, and execute other functions. The use of metamaterials in wireless applications is becoming widespread due to its extraordinary properties such as evanescent wave amplification and negative refractive index. This paper studies a soft, flexible and stretchable Complementary Split Ring Resonator (CSRR) metamaterial energy harvester using a volume of 5.6 × 5.6 × 1 mm 3 on a Polydimethylsiloxane (PDMS) substrate. The CSRR is backed by a ground plane to absorb the incident power, and a via (load) is used to maximize the power harvesting efficiency. For stretchability, a typically rigid patch of the CSRR is replaced by the serpentine mesh. From the ANSYS HFSS simulation, it is found that the serpentine structure helps to reduce the size of the CSRR due to an increase in electrical length. The structure can also achieve high-quality factor (Q-factor), thereby enabling almost unity efficiency. The CSRR metamaterials can be used in future for wireless applications to integrate with the skin, the heart, and the brain

Multifunctional antimicrobial biometallohydrogels based on amino acid coordinated self-assembly

There is a real need for new antibiotics against self‐evolving bacteria. One option is to use biofriendly broad‐spectrum and mechanically tunable antimicrobial hydrogels that can combat multidrug‐resistant microbes. Whilst appealing, there are currently limited options. Herein, broad‐spectrum antimicrobial biometallohydrogels based on the self‐assembly and local mineralization of Ag+‐coordinated Fmoc‐amino acids are reported. Such biometallohydrogels have the advantages of localized delivery and sustained release, reduced drug dosage and toxicity yet improved bioavailability, prolonged drug effect, and tunable mechanical strength. Furthermore, they can directly interact with the cell walls and membrane, resulting in the detachment of the plasma membrane and leakage of the cytoplasm. This leads to cell death, triggering a significant antibacterial effect against both Gram‐negative (Escherichia coli) and Gram‐positive (Staphylococcus aureus) bacteria in cells and mice. This study paves the way for developing a multifunctional integration platform based on simple biomolecules coordinated self‐assembly toward a broad range of biomedical applications