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The increasing market demand for squalene requires novel biotechnological production platforms. Schizochytrium sp. is an industrial oleaginous host with high potential for squalene production due to its abundant native acetyl-CoA pool. We first found that iron starvation led to the accumulation of 1.5 g/L of squalene by Schizochytrium sp., which was 40-fold higher than in the control. Subsequent transcriptomic and lipidomic analyses showed that the high squalene titer is due to the diversion of precursors from lipid biosynthesis and increased triglycerides (TAG) content for squalene storage. Furthermore, we constructed the engineered acetyl-CoA C-acetyltransferase (ACAT)-overexpressing strain 18S::ACAT, which produced 2.79 g/L of squalene, representing an 86% increase over the original strain. Finally, a nitrogen-rich feeding strategy was developed to further increase the squalene titer of the engineered strain, which reached 10.78 g/L in fed-batch fermentation, a remarkable 161-fold increase over the control. To our best knowledge, this is the highest squalene yield in thraustochytrids reported to date. This article is protected by copyright. All rights reserved.

Terpenoids represent one of the largest class of chemicals in nature, which play important roles in food and pharmaceutical fields due to diverse biological and pharmacological activities. Microorganisms are recognized as a promising source of terpenoids due to its short growth cycle and sustainability. Importantly, microalgae can fix inorganic carbon through photosynthesis for the growth of themselves and the biosynthesis of various terpenoids. Moreover, microalgae possess effective biosynthesis pathways of terpenoids, both the eukaryotic mevalonic acid (MVA) pathway and the prokaryotic methyl-D-erythritol 4-phosphate (MEP) pathway. In recent years, various genetic engineering strategies have been applied to increase target terpenoid yields, including overexpression of the rate-limited enzymes and inhibition of the competing pathways. However, since gene-editing tools are only built in some model microalgae, fermentation strategies that are easier to be operated have been widely successful in promoting the production of terpenoids, such as changing culture conditions and addition of chemical additives. In addition, an economical and effective downstream process is also an important consideration for the industrial production of terpenoids, and the solvent extraction and the supercritical fluid extraction method are the most commonly used strategies, especially in the industrial production of β-carotene and astaxanthin from microalgae. In this review, recent advancements and novel strategies used for terpenoid production are concluded and discussed, and new insights to move the field forward are proposed. KEY POINTS: • The MEP pathway is more stoichiometrically efficient than the MVA pathway. • Advanced genetic engineering and fermentation strategies can increase terpene yield. • SFE has a higher recovery of carotenoids than solvent extraction.

This study presents a monitoring system with a $4\times4$ handmade cross-type capacitive plantar pressure (CCPP) sensor. This system includes a prototype detection module and a display interface, and it is implemented as a wearable device. The prototype detection module consists of a low dropout regulator (commercial IC) utilized to regulate a stable DC voltage with 3.7 V Li-ion battery for a whole wearable device and a customized capacitance-to-digital converter (CDC) chip is employed to convert capacitances into the digital data. The CDC includes a capacitance-to-voltage converter (CVC) and 10-bit successive approximation register analog-to-digital converter are fabricated via the TSMC $0.18~\mu \text{m}$ 1P6M 3.3 V process. CVC is characterized by its selectability of detection points from 1 to 64 ( $8\times8$ cross-type capacitive array). This type of converter is controlled by digital codes of a field-programmable gate array (FPGA) and has embedded functions of a self-separated input signal, which is applied to scan each detection point of the cross-type capacitive sensors, and a crosstalk attenuation (CA) is used to reduce parasitic capacitances and the effects of relative humidity and temperature of the environment for cross-type capacitive sensors. To demonstrate improvements of the CA, a multi-physics simulation software, COMSOL Multiphysics, was utilized to verify the performance of the CA. The handmade $4\times4$ CCPP sensor is modeled in COMSOL Multiphysics and simulated with/without CA. Finally, the simulated results reveal that the function of CA can reduce parasitic capacitances and the effects of the relative humidity and temperature caused by the environment effectively at the femtofarad level. The cross-type structure of a capacitive array has an advantage due to an $M\times N$ array, which only requires $M + N$ tracks of input/output (I/O) ports to reduce the complexity of I/O connections. The measured results of the prototype detection module shown on the display interfaces reveal the positions and strengths of the corresponding capacitances of the CCPP sensor. The range of sensing capacitance is from 0 pF to 5.406 pF, the minimum sensing step is 15 fF, the accuracies of the handmade CCPP sensor and prototype detection module are −11.6/9.96 % and −8.65/5.54 %, respectively, and the sensitivity is 8 fF/N. The conversion time for one capacitance is 0.28 ms, and the maximum conversion time for 64 capacitances is 18.29 ms.

Healthcare systems have been an important part of the research on consumer electronics in recent years. To be a mass-market product, a healthcare system is combined with a home control system. In this article, an ultra-high-frequency radio-frequency-identification (UHF RFID) wireless interface is built and implemented for the bio-signal monitoring of the healthcare system. This interface is composed of a digital baseband processor with an application specific integrated circuit (ASIC) for the RFID reader and tag. All functions are implemented to fit the requirement of electronic product code class 1 generation 2 protocol, such as cyclic redundancy check/verify, pulse interval encoding, and bi-phase space coding. The system platform was built to obtain bio-signals, which can demonstrate the hand-shaking stage and communication between the reader and tag at the same time. The tag was fabricated under the 180-nm standard CMOS process with the average power consumption of only 73.62 $\mu \text{W}$ . The reader was implemented by a field programmable gate array in the system. The power consumption of the entire system combined with those in our previous works, which include analog front-end and radio-frequency front-end, is considered. It achieves 75 $\mu \text{W}$ , which is lower than those achieved with the existing state-of-the-art wireless interface. Moreover, the wearable device with ASICs is proposed to feature on relative low power and small size. Thus, it is more suitable for consumer electronics.

Fungal endophytes establish symbiotic relationships with host plants, which results in a mutual growth benefit. However, little is known about the plant genetic response underpinning endophyte colonization. Phomopsis liquidambaris usually lives as an endophyte in a wide range of asymptomatic hosts and promotes biotic and abiotic stress resistance. In this study, we show that under low nitrogen conditions P. liquidambaris promotes rice growth in a hydroponic system, which is free of other microorganisms. In order to gain insights into the mechanisms of plant colonization by P. liquidambaris under low nitrogen conditions, we compared root and shoot transcriptome profiles of root-inoculated rice at different colonization stages. We determined that genes related to plant growth promotion, such as gibberellin and auxin related genes, were up-regulated at all developmental stages both locally and systemically. The largest group of up-regulated genes (in both roots and shoots) were related to flavonoid biosynthesis, which is involved in plant growth as well as antimicrobial compounds. Furthermore, genes encoding plant defense-related endopeptidase inhibitors were strongly up-regulated at the early stage of colonization. Together, these results provide new insights into the molecular mechanisms of plant-microbe mutualism and the promotion of plant growth by a fungal endophyte under nitrogen-deficient conditions.

This work presents a portable wireless urine detection system which consists of an electrochemical readout application specific integrated circuit (ASIC) and a biosensor composed of 2, 2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) and carbon nanotube (ABTS-CNT) for the detection of urine albumin-to-creatinine ratio (UACR). The ASIC includes a potentiostat, a digital circuitry and a power management circuit which can perform electrochemistry techniques with a dual-channel screen-printing carbon electrode (SPCE). Electrochemical experiments on the proposed biosensor (SPCE|ABTS-CNT|Nafion) have revealed promising sensing characteristics for creatinine and human serum albumin detection. Practical urine tests has demonstrated the capability of the proposed urine detection system for UACR detection with both the power-efficient readout ASIC and the ABTS-CNT biosensor. A user-friendly prototype has also been designed which can be useful for either personal health administrationor homecare.

An artificial intelligence wireless stimulating system-on-chip (AIWSSoC) is proposed in this study. The AIWSSoC integrates two EEG monitoring channels, wireless interface and charging, a UART interface, an epilepsy detection algorithm, a power management circuit, an electrical stimulation circuit, and an optogenetic stimulation controller into a chip. Moreover, the AIWSSoC functions as a seizure suppressor with an off-chip device. Animal experimental result verifies the function of recording and different types of electrical stimulations.

This paper presents an application specific integrated circuit (ASIC) for electrochemistry acquisition with a high power-efficient current readout circuit. The proposed ASIC includes a current-sensing voltage-controlled oscillator (VCO)-based continuous-time delta-sigma modulator (CTDSM), a decimation filter, an UART package generator and low-dropout regulators. The proposed VCO-based CTDSM features direct connection to the electrochemical sensor without pre-amplifier, which can directly quantize the reaction current signal to achieve a better power efficiency. Second order noise shaping is achieved by using an additional capacitor as a passive integrator and a dual-VCO structure as an integrator in phase domain. The digital circuitry mainly functions as a decimation filter and an UART package generator. The proposed ASIC implemented in TSMC 0.18\ \mu\mathrm{m}$ CMOS process can achieve 73 dB dynamic range (DR) and power efficiency of 0.73 while consuming only $73.9\ \mu\mathrm{W}$ . The total chip area is 2.25 mm2.

Electrocardiography (ECG) is a fundamental method not only commonly used in the hospital for clinical requirement but also widely adopted in home and personal healthcare systems to obtain the electrical activity of the heart. An arrhythmia monitoring system is proposed and used in a clinical trial. The proposed system has three parts. The first is a high-resolution, low-power analog front-end circuit for implementing bio-signal sensing circuits. This part is developed with a chopper-based pre-amplifier and a high-pass sigma–delta modulator. The features of the circuits are low complexity, high resolution, and low power consumption. The second part is a digital signal processor with a decimation filter and a universal asynchronous receiver/transmitter package generator. The last part is used to realize a software interface on smartphone for ECG signal recording, display, and classification. A wavelet-based classification method is also proposed to classify the rhythm. The chip used in the system is fabricated through the 0.18 $\boldsymbol {\mu }\text{m}$ standard complementary metal–oxide–semiconductor process, and the operation voltage is 1.2 V. The classification algorithm is verified with data from the MIT/BIH arrhythmia database. The accuracy of beat detection and arrhythmia classification is 99.4% and 95.83%, respectively. Eight patients are enrolled in a human study to verify the performance of the proposed arrhythmia monitoring system. Results show that the system can acquire and classify ECG signals.

Schizochytrium sp. has received increasing attention as promising commercial resource for the sustainable production of lipids, due to their fast growth rate and high lipid content. However, the price of glucose represents a significant proportion of the total substrate cost. Therefore, in this study, the lignocellulosic hydrolysate of corn stover hydrolysate (CSH) was used as low-cost culture medium to replace glucose in Schizochytrium sp. fermentation. When Schizochytrium sp. HX-308 was fermented with 20% glucose from CSH and 80% of glucose from pure glucose, the lipid production reached 21.2 g L

Heart-sound auscultation is a rapid and fundamental technique used for examining the cardiovascular system. The main components of heart sounds are the first and second heart sounds. Discriminating these heart sounds under the presence of additional heart sounds and murmurs will be difficult. To recognize these signals efficiently, this study proposes a monitoring system with phonocardiogram and electrocardiogram. This system has two key points. The first is chip implementation, including capacitor coupled amplifier, transimpedance amplifier, high-pass sigma–delta modulator, and digital signal processing block. The chip in the system is fabricated in 0.18 μm standard complementary metal–oxide–semiconductor process. The second is a software application on smartphones for heart-related physiological signal recording, display, and identification. A wavelet-based QRS complex detection algorithm verified by MIT/BIH Arrhythmia Database is also proposed. The overall measured positive prediction, sensitivity, and error rate of the proposed algorithm are 99.90%, 99.82%, and 0.28%, respectively. During auscultation, doctors may refer to these physiological signals displayed on the smartphone and simultaneously listen to the heart sounds to diagnose the potential heart disease. By taking advantage of signal visualization and keeping the original diagnosis procedure, the uncertainty existing in heart sounds can be eliminated, and the training period to acquire auscultation skills can be reduced.

The endophytic fungus Phomopsis liquidambaris efficiently promotes the nitrogen metabolism and growth of host plants such as rice and peanut. However, a lack of genetic tools limits further research regarding the mechanisms of interaction between P. liquidambaris and its host plants. Herein, a CRISPR/Cas9 system for targeted gene disruption in this strain was first constructed and optimized. The knock-out efficiency increased to over 60% when the ku70 or ku80 gene (involved in nonhomologous end-joining, NHEJ) was disrupted. Furthermore, the CRISPR/Cas9 system was applied to disrupt the PmkkA gene, encoding a mitogen-activated protein kinase kinase (MAPKK) in the cell-wall integrity (CWI) MAPK pathway of the strain. The ΔPmkkA mutant strain induced higher reactive oxygen species (ROS) production, chitinase activity and glucanase activity in rice seedlings than wild-type P. liquidambaris (WT), resulting in growth inhibition and strong resistance on rice. These results suggested that the PmkkA gene is crucial during the interaction with rice and may play a role in inhibiting the immune system of host plants. The CRISPR-Cas9 system will be of great use for the study of the interaction between P. liquidambaris and its host plants.

This study presents an intelligent stethoscope that can visualize heart sound signals and can simultaneously measure human's electrocardiogram (ECG) and heart sounds. The proposed stethoscope can be used in hospitals and telemedicine through an internet of things (IoT) system and a cloud database. The proposed stethoscope includes three parts, namely, a front-end device for ECG and heart sound measurement, a smart device application (APP), and a cloud server. The ECG-measuring device is designed for single lead measurement and has low power consumption and IoT-based design, which can send real-time ECG data to the smart device APP. Simultaneously, the heart-sound-measuring device combined with a traditional stethoscope head is used to measure heart sound signals. This device includes an analog front-end circuit and a microphone to filter environmental noises and to record heart sound signals. Heart sound signals are transmitted to the APP by using a Bluetooth Low Energy module. The smart device APP can display synchronized and real-time signals, including ECG and heart sounds. Meanwhile, those signals are recorded in smart devices and are uploaded to the cloud server, where doctors and users can diagnose and monitor healthcare anytime. The cloud server can store previous signals and can realize telemedicine through a web user interface. The proposed intelligent stethoscope is applied on human trials in the National Cheng Kung University Hospital.

Filamentous fungi can produce many valuable secondary metabolites; among these fungi, endophytic fungi play an ecological role in mutualistic symbiosis with plants, including promoting plant growth, disease resistance, and stress resistance. However, the biosynthesis of most secondary metabolites remains unclear, and knowledge of the interaction mechanisms between endophytes and plants is still limited, especially for some novel fungi, due to the lack of genetic manipulation tools for novel species. Herein, we review the newly discovered strategies of gene disruption, such as the CRISPR-Cas9 system, the site-specific recombination Cre/loxP system, and the I-SceI endonuclease-mediated system in filamentous fungi. Gene expression systems contain using integration of target genes into the genome, host-dependent expression cassette construction depending on the host, a host-independent, universal expression system independent of the host, and reporter-guided gene expression for filamentous fungi. Furthermore, the Newly CRISPRi, CRISPRa, and the selection markers were also discussed for gene disruption and gene expression were also discussed. These studies lay the foundation for the biosynthesis of secondary metabolites in these organisms and aid in understanding the ecological function of filamentous fungi.

This study proposes an artificial intelligence of things (AIoT) system for electrocardiogram (ECG) analysis and cardiac disease detection. The system includes a front-end IoT-based hardware, a user interface on smart device’s application (APP), a cloud database, and an AI platform for cardiac disease detection. The front-end IoT-based hardware, a wearable ECG patch that includes an analog front-end circuit and a Bluetooth module, can detect ECG signals. The APP on smart devices can not only display users’ real-time ECG signals but also label unusual signals instantly and reach real-time disease detection. These ECG signals will be uploaded to the cloud database. The cloud database is used to store each user’s ECG signals, which forms a big-data database for AI algorithm to detect cardiac disease. The algorithm proposed by this study is based on convolutional neural network and the average accuracy is 94.96%. The ECG dataset applied in this study is collected from patients in Tainan Hospital, Ministry of Health and Welfare. Moreover, signal verification was also performed by a cardiologist.

The number of studies on closed-loop detection and electrical stimulation systems [1]–[2] for efficient control of neurological disorders is increasing, because recent clinical studies have shown their efficiency and usefulness in symptom suppression. Electrical stimulation can produce enough stimulation to affect a large range of nerves. However, all nerves near the stimulus are excited and hurt, and over time, currents start to exceed acceptable limits. Therefore, optogenetic stimulation [3]–[4] has become compelling in recent years due to several advantages: (1) no artificial noise on the EEG; (2) ability to stimulate specific nerves; and (3) no injurious effects on nerves. In this study, a wireless programmable stimulating system-on-chip (WPSSoC) is reported that provides wireless open/closed-loop optogenetic and electrical stimulation to improve treatment for epilepsy suppression. The system is demonstrated on programmable stimulation parameters wirelessly controlled by a software Graphical User Interface (GUI) on a computer. Moreover, an animal experiment conducted on optogenetic tissue was successful, thereby demonstrating that the nerve injury on optogenetic stimulation is lower than that of electrical stimulation.

Physical review accelerators and beams 22(12), 123403 (2019). doi:10.1103/PhysRevAccelBeams.22.123403, In state of the art photoemission electron sources, the transverse emittance of the electron beam is approaching its intrinsic value from the cathode. To reduce the intrinsic emittance, it is straightforward to tune the photon energy of the drive laser toward the photocathode emission threshold. This paper aims at constructing an improved model which takes into account an intermediate energy level to better explain the near threshold photoemission for semiconductors. A dynamic model is also proposed to evaluate the cathode degradation process due to surface oxidation. The models agree well with published results for different materials under various conditions, including electric field, temperature and vacuum condition. The dynamic model predicts that near threshold emission of an oxidized Cs3Sb cathode outperforms UV photoemission of typical metal cathodes in terms of both quantum efficiency and intrinsic emittance. With the oxidization layer, the robustness of semiconductor cathodes to gun vacuum condition may be comparable to a metal cathode. This, however, needs further testing., Published by American Physical Society, College Park, MD

Filamentous ascomycete Phomopsis sp. are common inhabitants of natural ecosystems and, as saprophytes, are largely responsible for the destructive decay of litterfall, promoting the carbon and nitrogen cycles. Phomopsis liquidambari B3 can establish mutualistic symbiosis with a broad spectrum of crop plants. Colonizing dynamics observations and a growth promotion assay of rice and Arabidopsis thaliana revealed that the B3 colonization strategy is host-adapted and resulted in different growth promotions influenced by N availability. However, the biochemical mechanisms and underlying genetics of the saprophyte transition to an endophyte are poorly understood. Here, the transcriptome features of generalist P . liquidambari and highlighted gene sets involved in the lifestyle transition from saprophytism to endophytism were reported. Most notable were genes for translation, ribosome biogenesis and MAPK signaling, several of which were only up-regulated in endophytic B3. Coordinated up-regulation of genes encoding enzymes involved in phenylalanine, tyrosine and tryptophan biosynthesis were preceded by secondary metabolite induction, which was encountered with host defense. Quantitative PCR validates the reliability of RNA-seq. Dissection at the molecular level facilitated a deeper understanding of P. liquidambari adaptation to hosts and the complex natural environment to play a role in sustainable agriculture and carbon and nitrogen cycles.

In this paper, a cross-domain integration system composed of a gene transfer technique with a pre-clinical trial, an on-chip circuit design, an off-chip hardware with peripheral unit integration, and a custom software is presented. Opsin protein-gene transfer is successfully conducted to demonstrate that gene transfer treatment with optical stimulation has several benefits compared with electrical treatment. The proposed wireless programmable stimulating system on chip (WPSSoC) is composed of two sensing channels combined with a decimation filter to acquire intracranial electroencephalography (iEEG), an epilepsy detection unit (EDU), a stimulator with a waveform controller, and an ultra-low-power embedded transceiver. The equivalent sample rate of sensed data is 375 samples/s with 16-bit output data. The performance of intermodulation distortion with a third order (IMD3) is approximately 68 dB. The EDU extracts approximate entropy (ApEn) and spectrum bins for the classifier. The stimulator with controller features on the waveform-adjustable function to provide 0-510 μA of electrical stimulation and 0-50 mW of optical stimulation. The proposed transceiver is implemented with a 2.45 GHz on-off keying (OOK) carrier frequency. Transmitter and receiver front-ends perform at 50.6 and 12.7 pJ/bit of energy per bit, respectively. Power consumption and area of WPSSoC are about 1 mW and 13.67 mm2 in a 0.18 μm process, respectively. Circuits of each part are integrated in a 4.3 cm × 2 cm printed circuit board. The shrunk device is verified with Thy1-ChR2-YFP gene transfer in C57BL/6 mice by using a custom software which is used to provide commands and monitor iEEG.

A newly isolated Pseudomonas fragi P121 strain in a soil sample taken from the Arctic Circle is able to produce trehalose. The P121 strain was able to grow at temperatures ranging from 4 to 25 °C, had an optimum pH of 6.5, and an optimum salt concentration of 2 %. The P121 strain had a survival rate of 29.1 % after being repeatedly frozen and thawed five times, and a survival rate of 78.9 % when placed in physiological saline for 15 days at 20 °C after cold shock, which is far higher than the type strain Pseudomonas fragi ATCC 4973. The P121 strain could produce 2.89 g/L trehalose, which was 18.6 % of dry cell weight within 52 h in a 25 L fermention tank using the malt extract prepared from barley as medium at 15 °C, while only 11.8 % of dry cell weight at 20 °C. These results suggested that cold stress promoted the strain producing trehalose. It is the first reported cold-tolerant bacterium that produces trehalose, which may protect cells against the cold environment.

Recently, the nodal line semimetals have attracted considerable interests in condensed matter physics. We show that their distinct band structure can be detected by measuring the collective modes. In particular, we find that the dependence of the plasmon frequency $\omega_p$ on the electron density $n$ follows a $\omega_p \sim n^{1/4}$ law in the long wavelength limit. Our results will be useful in the ongoing search for new candidates of nodal line semimetals., Comment: 9 pages,4 figures, figures updated

This study proposes an electrocardiographic (ECG) monitoring and emotion stabilization system that is composed of an acquisition system on chip and an Android system. This system has three main parts. The first part is a low-power analog front-end circuit for biosignal sensing. The second part comprises a digital signal processor for down sampling, filtering, and QRS detection. The last part is an emotion stabilization feedback control based on an Android-operated physiological information platform. This platform allows physiological information display, data recording, signal processing, and analysis. All circuits are fabricated in a TSMC 0.18 μm standard CMOS process.

This paper proposes a combined heart rate detection and energy harvesting system operated on smart phones for vehicle drivers. The proposed system consists of four parts. The first part includes a high-resolution and low-power analog front-end chip to implement a biosignal sensing module (BSM). The second part comprises a digital signal processor with a high-recognition-rate QRS detection algorithm. The third part includes a power management circuit that harvests energy from a smart phone. This part provides a stable voltage supply to the BSM. The power conversion efficiency of the proposed rectifier exceeds 85%. The last part executes a data recording and heart rate variability analysis software based on the Android system. All chips are fabricated in a TSMC 0.18 μm standard CMOS process.