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A wireless closed-loop system for optogenetic peripheral neuromodulation
摘要： The fast-growing field of bioelectronic medicine aims to develop engineered systems that can relieve clinical conditions by stimulating the peripheral nervous system. This type of technology relies largely on electrical stimulation to provide neuromodulation of organ function or pain. One example is sacral nerve stimulation to treat overactive bladder, urinary incontinence and interstitial cystitis (also known as bladder pain syndrome). Conventional, continuous stimulation protocols, however, can cause discomfort and pain, particularly when treating symptoms that can be intermittent (for example, sudden urinary urgency). Direct physical coupling of electrodes to the nerve can lead to injury and inflammation. Furthermore, typical therapeutic stimulators target large nerve bundles that innervate multiple structures, resulting in a lack of organ specificity. Here we introduce a miniaturized bio-optoelectronic implant that avoids these limitations by using (1) an optical stimulation interface that exploits microscale inorganic light-emitting diodes to activate opsins; (2) a soft, high-precision biophysical sensor system that allows continuous measurements of organ function; and (3) a control module and data analytics approach that enables coordinated, closed-loop operation of the system to eliminate pathological behaviours as they occur in real-time. In the example reported here, a soft strain gauge yields real-time information on bladder function in a rat model. Data algorithms identify pathological behaviour, and automated, closed-loop optogenetic neuromodulation of bladder sensory afferents normalizes bladder function. This all-optical scheme for neuromodulation offers chronic stability and the potential to stimulate specific cell types.
关键词： optogenetics,closed-loop system,bladder function,wireless implant,bioelectronic medicine,neuromodulation
更新于2025-09-23 15:23:52
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Pd nanoparticle-decorated hydroxy boron nitride nanosheets as a novel drug carrier for chemo-photothermal therapy
摘要： A multi-stimuli responsive nanoagent, hydroxy boron nitride nanosheets and Pd nanohybrids (Pd@OH-BNNS), was studied. The well-dispersed hydroxy boron nitride nanosheets were prepared via a facile thermal substitution approach. Pd@OH-BNNS was endowed with a photothermal property after in situ formation of Pd nanoparticles on the surface of the nanosheets. Pd@OH-BNNS as a drug delivery carrier exhibited high loading capability for the anticancer drug doxorubicin. The release of doxorubicin from the nanohybrids was triggered by a decrease in pH, and increases in glutathione concentration and near-infrared irradiation. The faster release behavior of the nanohybrids under near-infrared irradiation was confirmed by a cellular uptake study. In addition, local hyperthermia was verified using an imaging test and an infrared thermal camera. Tumor growth was remarkably inhibited in mice after two weeks of treatment with Pd@OH-BNNS/doxorubicin injection, demonstrating the high efficacy of combining chemotherapy and photothermal therapy. The Pd@OH-BNNS as a drug delivery system exhibited good stability, low cytotoxicity and multi-stimuli responsiveness.
关键词： photothermal therapy,Pd nanoparticles,drug delivery system,hydroxy boron nitride,nanohybrids
更新于2025-09-23 15:23:52
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Numerical evaluation of the optical-splitter system efficiency using a TCO as optical splitter
摘要： In the present work, we simulate the J-V characteristic of a solar cell combination to evaluate the efficiency in an optical splitter system. Two different transparent conductive oxides (TCO) were used as splitters (ITO and SnO2:F). The spectral response of the TCOs was modeled according to Drude's theory, using different concentration values. Then, the J-V characteristics of the cells were simulated by SCAPS 1-D, using the spectra obtained for each TCO by superimposing the spectral response on the solar spectrum. The results indicate that solar cells can achieve efficiencies in the system above 17 % using ITO as splitter with a positive gain for both solar cells.
关键词： splitter system,solar cell simulation,TCO,SCAPS
更新于2025-09-23 15:23:52
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Squeezing-induced giant Goos-H?nchen shift and hypersensitized displacement sensor in a two-level atomic system
摘要： We analyze an efficient scheme to enhance the Goos-H?nchen (GH) shifts of the reflected and transmitted beams in a cavity containing two-level atomic medium. A broadband squeezed vacuum field is injected into the cavity to interact with the atomic medium. In the bad cavity limit, the Bloch equations for the atomic operators are identical to those in the free space, but with the modification of the system parameters. Using experimentally achievable parameters, we identify the conditions under which the squeezed vacuum allows us to enhance the GH shifts of the reflected and transmitted beams beyond what is achievable in the absence of the squeezed vacuum. The enhanced GH shifts originate from the coherent population oscillations controlled by the squeezed vacuum field. Furthermore, we also find that the GH shifts of the reflected and transmitted beams depend sensitively on the relative phase between the control field and the squeezed vacuum field. Subsequently, we propose a scheme for such a configuration of the GH shift as a family of hypersensitized displacement sensors. Based on the numerical analysis, the detection sensitivity and minimum detectable value for the tiny displacement can reach approximately 2340 μm/nm and 14.4 pm, respectively.
关键词： coherent population oscillations,Goos-H?nchen shift,two-level atomic system,displacement sensor,squeezed vacuum
更新于2025-09-23 15:23:52
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Energy Management and Coordinated Control Strategy of PV/HESS AC Microgrid during Islanded Operation
摘要： An energy management control strategy is proposed for an islanded AC microgrid with the hybrid energy storage system (HESS) including the battery and the supercapacitor (SC). According to the state of charge(SOC) of the battery, the photovoltaic (PV) system can work in either maximum power point tracking (MPPT) mode or load power tracking (LPT) mode to prevent the battery from over charging. Similarly, the load shedding control (LSC) is adopted to prevent the battery from over discharging. A virtual impedance control strategy is proposed to achieve effective power sharing in hybrid energy storage systems, where battery provides steady state power and SC only supports transient power fluctuations. The terminal voltage of SC can be restored to the initial value automatically by introducing a high pass filter in the voltage control loop. The AC bus voltage maintains constant using the voltage secondary controller to compensate the voltage droop caused by the virtual impedance control strategy. Simulation results under typical working conditions verify the correctness and effectiveness of the proposed control strategy.
关键词： hybrid energy storage system (HESS),energy management,state of charge (SOC),Coordinated control,voltage restoration,islanded operation,virtual impedance
更新于2025-09-23 15:23:52
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[IEEE 2018 IEEE Asia-Pacific Conference on Antennas and Propagation (APCAP) - Auckland (2018.8.5-2018.8.8)] 2018 IEEE Asia-Pacific Conference on Antennas and Propagation (APCAP) - An Automatic Sun Tracking System for Fiber Optic Lighting
摘要： An automatic sun tracking system for fiber optic lighting is proposed. Using STC89C52RC microcontroller as the core controller, together with the steering gear to control the system daylighting, the system is able to trigger the sun tracking system and auxiliary lighting system automatically for overheating protection and brightness adjustment. A practical sun tracking system with hardware and software is implemented and validated by experiments.
关键词： steering gear,sensor,sun tracking system,Fiber optic lighting
更新于2025-09-23 15:23:52
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - High Spatial Soil Moisture Mapping Using Small Unmanned Aerial System
摘要： Soil moisture is of fundamental importance to many hydrological, biological and biogeochemical processes, plays an important role in the development and evolution of convective weather and precipitation，and impacts precision agriculture, water resource management, and flood runoff prediction. The launch of NASA’s Soil Moisture Active/Passive (SMAP) mission in 2015 provide new passive global measurements of soil moisture and surface freeze/thaw state at fixed crossing times and spatial resolutions of 36 km. There exists a need for measurements of soil moisture on much smaller spatial scales and arbitrary diurnal times for SMAP validation, precision agriculture, flood runoff prediction, evaporation and transpiration studies of boundary layer heat transport, and tundra thaw studies. The Lobe Differencing Correlation Radiometer (LDCR) provides a means of mapping soil moisture on spatial scales as small as several meters (i.e., the height of the platform). Compared with various other proposed methods of validation based on either in situ measurements or existing airborne sensors suitable for manned aircraft deployment, the integrated design of the LDCR on a lightweight small unmanned aerial system (sUAS) can provide sub-watershed (~km scale) coverage at very high spatial resolution (~15 m) suitable for scaling scale studies. The Tempest sUAS, flies at very low operator cost compared to manned aircraft. To demonstrate the LDCR Rev A and Rev B, several flights had been performed during field experiments at the Canton Oklahoma Soilscape site on September 8th and 9th, 2015 and Yuma Colorado Irrigation Research Foundation (IRF) site from June to August 2016, and October 2017. The LDCR antenna temperature and soil moisture maps will be presented, and scientific intercomparisons between LDCR soil moisture data and in-situ measurements will be presented.
关键词： unmanned aerial system,L-band radiometer,soil moisture mapping
更新于2025-09-23 15:23:52
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[IEEE 2018 IEEE 21st International Multi-Topic Conference (INMIC) - Karachi, Pakistan (2018.11.1-2018.11.2)] 2018 IEEE 21st International Multi-Topic Conference (INMIC) - Optimum Unit Sizing of Stand-Alone PV-WT-Battery Hybrid System Components Using Jaya
摘要： Renewable energy sources (RESs) are considered as reliable and green electric power generations. Photovoltaic (PV) and wind turbine (WT) are used to provide electricity in remote areas. The optimum unit sizing of hybrid RESs components is a vital challenge in a stand-alone system. This paper presents Jaya algorithm for optimum unit sizing of a PV-WT-Battery hybrid system to fulfill the consumer’s load at minimal cost. The reliability of the system is considered by a maximum allowable loss of power supply probability (LP SPmax). The results obtained from the Jaya algorithm show that the PV-WT-Battery hybrid system is the most economical and cost-effective solution for all proposed LP SPmax values as compared to PV-Battery and WT-Battery systems.
关键词： Unit sizing,optimization,renewable energy sources,energy storage system,LPSP
更新于2025-09-23 15:23:52
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[IEEE 2018 9th International Conference on Information Technology in Medicine and Education (ITME) - Hangzhou, China (2018.10.19-2018.10.21)] 2018 9th International Conference on Information Technology in Medicine and Education (ITME) - MobMivs: Implementing an Efficient Medical Image Visualization System for Mobile Telemedicine
摘要： As medical devices have excellent resolutions and have become better connected to the Internet, doctors and patients are beginning to expect medical images to be available on mobile device for making a diagnosis or consultative viewing. However, the performance of querying and accessing medical images in anytime and anywhere using mobile device is still an issue. In this paper, we implement an medical image visualization system to efficiently query and access medical images by using smartphone, which has the following new features: 1) an on-demand data transmission method is implemented using DICOM web service, and only the required meta data and image region or series are transmitted to mobile device; 2) a high performance cache component is designed to cache the recently requested images, which takes up less storage and obtains higher performance; 3) a convenient way is introduced to quickly obtain a specific patient's studies by scanning a patient's barcode or quick response code. The performance and stability of our proposed method as well as the prototype system is evaluated with real DICOM data sets. The results show that our app obtains high performance and stability in both Wi-Fi and 4G mobile network, which is expected to be an effective tool for mobile telemedicine.
关键词： Mobile medical image system,Web service,Mobile device,DICOM
更新于2025-09-23 15:23:52
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An image segmentation method of a modified SPCNN based on human visual system in medical images
摘要： An image segmentation method of a modified simplified pulse-coupled neural network (MSPCNN) based on human visual system (HVS) is proposed for medical images. The method successfully determines the stimulus input of the MSPCNN according to the characteristics of PCNN and HVS. In order to accomplish the goal, we attempt to deduce the sub-intensity range of central neurons firing by introducing neighboring firing matrix Q and calculating intensity distribution range based on a new MSPCNN(NMSPCNN), and then reveal the way how sub-intensity range parameter Sint generates the stimulus input Sioij closer to HVS. Besides, we try to substitute the above stimulus input into the MSPCNN to extract more suitable lesions for medical images. In contrast to prevalent PCNN models, the MSPCNN has higher segmentation accuracy rates and lower computational complexity because of the parameter setting method. Finally, the proposed method comparing with the state-of-the-art methods has a better performance, presenting the overall metric OEM with MIAS of 0.8784, DDSM of 0.8606 and gallstones of 0.8585.
关键词： Sub-intensity Range,Modified Simplified Pulse-coupled Neural Network,Image Segmentation,Stimulus Input,Human Visual System
更新于2025-09-23 15:23:52