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Abstract DELLA proteins are conserved master growth regulators that play a central role in controlling plant development in response to internal and environmental cues. DELLAs function as transcription regulators, which are recruited to target promoters by binding to transcription factors (TFs) and histone H2A via their GRAS domain. Recent studies showed that DELLA stability is regulated post-translationally via two mechanisms, phytohormone gibberellin-induced polyubiquitination for its rapid degradation, and Small Ubiquitin-like Modifier (SUMO)-conjugation to increase its accumulation. Moreover, DELLA activity is dynamically modulated by two distinct glycosylations: DELLA-TF interactions are enhanced by O-fucosylation, but inhibited by O-linked N-acetylglucosamine (O-GlcNAc) modification. However, the role of DELLA phosphorylation remains unclear as previous studies showing conflicting results ranging from findings that suggest phosphorylation promotes or reduces DELLA degradation to others indicating it has no effect on its stability. Here, we identify phosphorylation sites in REPRESSOR OF ga1-3 (RGA, an AtDELLA) purified from Arabidopsis by mass spectrometry analysis, and show that phosphorylation of two RGA peptides in the PolyS and PolyS/T regions enhances RGA activity by promoting H2A binding and RGA association with target promoters. Notably, phosphorylation does not affect RGA-TF interactions or RGA stability. Our study has uncovered a molecular mechanism of phosphorylation-induced DELLA activity.

Kumar and colleagues report cryo-EM structures of Arabidopsis O-fucosyltransferase SPINDLY in its apo and GDP-fucose bound states, revealing distinct active-site features enabling GDP-fucose recognition and surprisingly dynamic conformations that regulate its enzymatic activity.

The dynamic mode decomposition (DMD) algorithm is a widely used factorization and dimensionality reduction technique in time series analysis. When analyzing high-dimensional time series, the DMD algorithm requires extremely large amounts of computational power. To accelerate the DMD algorithm, we propose a quantum-classical hybrid algorithm that we call the quantum dynamic mode decomposition (QDMD) algorithm. Given a time series X ∈ Rn × (m + 1) with n ≫ m, the QDMD algorithm first executes quantum singular value decomposition on a matrix related to X and obtains a quantum state containing the main singular values and singular vectors of the decomposed matrix, then performs a low-sampling-frequency process on the obtained quantum state and computes the low-dimensional projection of the DMD operator through the sampling results. Finally, the algorithm computes the DMD eigenvalues and prepares the amplitude-encoding states of the DMD modes using the obtained classical information and X. Considering the main variables, the complexity of the QDMD algorithm is [Formula: see text], where [Formula: see text] denotes the number of samples. Compared with the classical DMD algorithm, which has complexity [Formula: see text], the QDMD algorithm provides an exponential acceleration of n, at the cost of greater dependence on M and ϵ. We test the effects of M on the QDMD algorithm in the specific application scenarios of data denoising, scene background extraction, and fluid dynamics analysis. We determined that the QDMD algorithm requires only a small number of samples M in specific applications, further demonstrating the quantum advantage of the QDMD algorithm in high-dimensional data analysis.

Variational quantum algorithms (VQAs) are widely applied in the noisy intermediate-scale quantum era and are expected to demonstrate quantum advantage. However, training VQAs faces difficulties, one of which is the so-called barren plateaus (BPs) phenomenon, where gradients of cost functions vanish exponentially with the number of qubits. In this paper, inspired by transfer learning, where knowledge of pre-solved tasks could be further used in a different but related work with training efficiency improved, we report a parameter initialization method to mitigate BP. In the method, a small-sized task is solved with a VQA. Then the ansatz and its optimum parameters are transferred to tasks with larger sizes. Numerical simulations show that this method could mitigate BP and improve training efficiency. A brief discussion on how this method can work well is also provided. This work provides a reference for mitigating BP, and therefore, VQAs could be applied to more practical problems.

Phytochrome signaling in the nucleus can activate expression of photosynthesis-associated genes in plastids. Here Yang et al. show that NCP is a dual-targeted protein that promotes phytochrome B localization to photobodies in the nucleus while facilitating PEP polymerase assembly in the plastids.

Regular monitoring of blood α-fetoprotein (AFP) and/or carcino-embryonic antigen (CEA) levels is important for the routine screening of liver cancer. However, AFP and CEA have a much lower specificity than des-γ-carboxyprothrombin (DCP) to detect liver cancer. Therefore, the study reported here was designed, to develop a screen-printed DCP immunosensor incorporating zinc oxide nanoparticles, for accurate determination of DCP. The designed immunosensor shows low detection limits for the detection of DCP: 0.440 ng/mL (based on impedance measurement), 0.081 ng/mL (based on real part of impedance measurement) and 0.078 ng/mL (based on imaginary part of impedance measurement), within the range of 3.125 ng/mL to 2000 ng/mL. In addition, there was little interference to DCP determination by molecules such as Na+, K+, Ca2+, Cl−, glucose, urea, and uric acid. It is therefore concluded that the DCP immunosensor developed and reported here is simple, inexpensive and effective, and shows promise in the rapid screening of early-stage liver cancer at home with a point-of-care approach.

The purpose of this study was to develop novel nanoscale biosensors using titania nanotubes (TNTs) made by anodization. Titania nanotubes were produced on pure titanium sheets by anodization at room temperature. In this research, the electrolyte composition ethylene glycol 250 mL/NH4F 1.5 g/DI water 20 mL was found to produce the best titania nanotubes array films for application in amperometric biosensors. The amperometric results exhibit an excellent linearity for uric acid (UA) concentrations in the range between 2 and 14 mg/dL, with 23.3 (µA·cm−2)·(mg/dL)−1 UA sensitivity, and a correlation coefficient of 0.993. The glucose biosensor presented a good linear relationship in the lower glucose concentration range between 50 and 125 mg/dL, and the corresponding sensitivity was approximately 249.6 (µA·cm−2)·(100 mg/dL)−1 glucose, with a correlation coefficient of 0.973.

Congo Tak-Shing Ching1,2,3, Tzong-Ru Chou1, Tai-Ping Sun1,2, Shiow-Yuan Huang3, Hsiu-Li Shieh21Graduate Institute of Biomedicine and Biomedical Technology; 2Department of Electrical Engineering, National Chi Nan University, Nantou, Taiwan; 3Department of Photonics and Communication Engineering, Asia University, Taichung, Taiwan, Republic of ChinaBackground: Cardiovascular and kidney diseases are a global public health problem and impose a huge economic burden on health care services. Homocysteine, an amino acid, is associated with coronary heart disease, while urea is a harmful metabolic substance which can be used to reflect kidney function. Monitoring of these two substances is therefore very important. This in vitro study aimed to determine whether homocysteine is extractable transdermally and noninvasively, and whether homocysteine and urea can be extracted simultaneously by reverse iontophoresis.Methods: A diffusion cell incorporated with porcine skin was used for all experiments with the application of a direct current (dc) and four different symmetrical biphasic direct currents (SBdc) for 12 minutes via Ag/AgCl electrodes. The dc and the SBdc had a current density of 0.3 mA/cm2.Results: The SBdc has four different phase durations of 15 sec, 30 sec, 60 sec, and 180 sec. It was found that homocysteine can be transdermally extracted by reverse iontophoresis. Simultaneous extraction of homocysteine and urea by reverse iontophoresis is also possible.Conclusion: These results suggest that extraction of homocysteine and urea by SBdc are phase duration-dependent, and the optimum mode for simultaneous homocysteine and urea extraction is the SBdc with the phase duration of 60 sec.Keywords: reverse iontophoresis, homocysteine, urea, monitoring, noninvasive, transdermal

Chih-Kuei Lee1, Congo Tak-Shing Ching2–4, Tai-Ping Sun2,3, Chun-Lang Tsai2, Wei Huang5, Hsin-Hung Huang6, Jen-Fu Kuo7, Li-Hang Lai6, Mei-Ya Chien8, Hsin-Hui Tseng9, Hui-Tzu Pan10, Shiow-Yuan Huang4, Hsiu-Li Shieh3, Wei-Hao Liu2, Chia-Ming Liu2, Hsin-Wei Huang21Hopkins Health Management Center, Puli Christian Hospital, Nantou, Taiwan, Republic of China; 2Graduate Institute of Biomedicine and Biomedical Technology, National Chi Nan University, Nantou, Taiwan, Republic of China; 3Department of Electrical Engineering, National Chi Nan University, Nantou, Taiwan, Republic of China; 4Department of Photonics and Communication Engineering, Asia University, Taichung, Taiwan, Republic of China; 5Division of Immunology and Rheumatology, Puli Christian Hospital, Nantou, Taiwan, Republic of China; 6Family Medical Department, Puli Christian Hospital, Nantou, Taiwan, Republic of China; 7Division of Endocrinology and Metabolism, Puli Christian Hospital, Nantou, Taiwan, Republic of China; 8Nutrition Department, Puli Christian Hospital, Nantou, Taiwan, Republic of China; 9Aboriginal Health Care, Puli Christian Hospital, Nantou, Taiwan, Republic of China; 10Department of Medical Research and Education, Puli Christian Hospital, Nantou, Taiwan, Republic of ChinaAbstract: The aim of this study was to find out the optimum combination of electroporation (EP) and reverse iontophoresis (RI) on noninvasive and transdermal determination of blood uric acid level in humans. EP is the use of high-voltage electric pulse to create nano-channels on the stratum corneum, temporarily and reversibly. RI is the use of small current to facilitate both charged and uncharged molecule transportation across the skin. It is believed that the combination of these two techniques has additional benefits on the molecules’ extraction across the human skin. In vitro studies using porcine skin and diffusion cell have indicated that the optimum mode for transdermal uric acid extraction is the combination of RI with symmetrical biphasic direct current (current density = 0.3 mA/cm2; phase duration = 180 s) and EP with 10 pulses per second (voltage = 100 V/cm2; pulse width = 1 ms). This optimum mode was applied to six human subjects. Uric acid was successfully extracted through the subjects’ skin into the collection solution. A good correlation (r2 = 0.88) between the subject’s blood uric acid level and uric acid concentrations in collection solutions was observed. The results suggest that it may be possible to noninvasively and transdermally determine blood uric acid levels.Keywords: Reverse iontophoresis, electroporation, uric acid, monitoring, noninvasive, transdermal

Tai-Ping Sun1,2,5, Hsiu-Li Shieh2, Congo Tak-Shing Ching1,2,5, Yan-Dong Yao3, Su-Hua Huang4, Chia-Ming Liu1, Wei-Hao Liu1, Chung-Yuan Chen21Graduate Institute of Biomedicine and Biomedical Technology, 2Department of Electrical Engineering, National Chi Nan University, Nantou, Taiwan, ROC; 3Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Hong Kong; 4Department of Biotechnology, Asia University, Taichung, Taiwan, ROC; 5These authors contributed equally to this workAbstract: This study aims to develop an amperometric glucose biosensor, based on carbon nanotubes material for reverse iontophoresis, fabricated by immobilizing a mixture of glucose oxidase (GOD) and multiwalled carbon nanotubes (MWCNT) epoxy-composite, on a planar screen-printed carbon electrode. MWCNT was employed to ensure proper incorporation into the epoxy mixture and faster electron transfer between the GOD and the transducer. Results showed this biosensor possesses a low detection potential (+500 mV), good sensitivity (4 μA/mM) and an excellent linear response range (r2 = 0.999; 0–4 mM) of glucose detection at +500 mV (versus Ag/AgCl). The response time of the biosensor was about 25 s. In addition, the biosensor could be used in conjunction with reverse iontophoresis technique. In an actual evaluation model, an excellent linear relationship (r2 = 0.986) was found between the glucose concentration of the actual model and the biosensor’s current response. Thus, a glucose biosensor based on carbon nanotube composites and incorporated with reverse iontophoresis function was developed.Keywords: amperometric, carbon nanotubes, glucose monitoring, biosensors, reverse iontophoresis

Congo Tak-Shing Ching1,2, Tai-Ping Sun1,2, Su-Hua Huang3, Chin-Sung Hsiao4, Ching-Haur Chang4, Shiow-Yuan Huang4, Yi-Juai Chen5, Chi-Sheng Cheng6, Hsiu-Li Shieh2, Chung-Yuan Chen21Graduate Institute of Biomedicine and Biomedical Technology, National Chi Nan University, Nantou, Taiwan; 2Department of Electrical Engineering, National Chi Nan University, Nantou, Taiwan; 3Department of Biotechnology, Asia University, Taichung, Taiwan; 4Department of Photonics and Communication Engineering, Asia University, Taichung, Taiwan; 5Department of Oral and Maxillofacial Surgery, Chung Shan Medical University Hospital, Taichung, Taiwan; 6Department of Oral and Maxillofacial Surgery, Taichung Veterans General Hospital, Taichung, TaiwanAbstract: Oral cancers are the 11th most common malignancy reported worldwide, accounting for 3% of all newly diagnosed cancer cases, and one with high mortality ratios among all malignancies. The objective of this study was to study the electrical properties of cancerous tongue tissue (CTT) and normal tongue tissue (NTT). Five tongue cancer patients participated in this study. A disposable probe incorporating four silver electrodes was used to measure the electrical properties of CTT and the surrounding NTT of patients. Measurements were performed at six frequencies: 20 Hz; 50 kHz; 1.3 MHz; 2.5 MHz; 3.7 MHz; and 5 MHz, with the amplitude of the applied voltage limited to 200mV. Four measurement parameters of impedance (Z), phase angle (θ), real part of impedance (R), and imaginary part of impedance (X) of tongue tissue were assessed to see if there was any significant difference in the values obtained in CTT and surrounding NTT. The intraclass correlation coefficient showed that all measurements were reliable. A significant difference (P < 0.05 for the four measurement parameters) was found at 50kHz between CTT and surrounding NTT. It was also found that Z and R of CTT were generally smaller than that of surrounding NTT. In conclusion, bioimpedance at a particular frequency is a potentially promising technique for tongue cancer screening.Keywords: bioimpedance, tongue, cancer, noninvasive, detection, screening

OBJECTIVES: This study aims to investigate the electrical properties of lumbar paraspinal muscles (LPM) of patients with acute lower back pain (LBP) and to study a new approach, namely Electrical Impedance Myography (EIM), for reliable, low-cost, non-invasive, and real-time assessment of muscle-strained acute LBP. DESIGN: Patients with muscle-strained acute LBP (n = 30) are compared to a healthy reference group (n = 30). Electrical properties of LPM are studied. BACKGROUND: EIM is a novel technique under development for the assessment of neuromuscular disease. Therefore, it is speculated that EIM can be employed for the assessment of muscle-strained acute LBP. METHODS: Surface electrodes, in 2-electrode configurations, was used to measure the electrical properties of patient's and healthy subject's LPM at six different frequencies (0.02, 25.02, 50.02, 1000.02, 3000.02, and 5000.02 kHz), with the amplitude of the applied voltage limited to 200 mV. Parameters of impedance (Z), extracellular resistance (Re), intracellular resistance (Ri), and the ratio of extracellular resistance to intracellular resistance (Re/Ri) of LBP patient's and healthy subject's LPM were assessed to see if significant difference in values obtained in muscle-strained acute LBP patients existed. RESULTS: Intraclass correlation coefficient (ICC) showed that all measurements (ICC>0.96 for all studying parameters: Z, Re, Ri, and Re/Ri) had good reliability and validity. Significant differences were found on Z between LBP patient's and healthy subject's LPM at all studying frequencies, with p

Many processes critical to plant growth and development are regulated by the hormone auxin. Auxin responses are initiated through activation of a transcriptional response mediated by the TIR1/AFB family of F-box protein auxin receptors as well as the AUX/IAA and ARF families of transcriptional regulators. However, there is little information on how auxin regulates a specific cellular response. To begin to address this question, we have focused on auxin regulation of cell expansion in the Arabidopsis hypocotyl. We show that auxin-mediated hypocotyl elongation is dependent upon the TIR1/AFB family of auxin receptors and degradation of AUX/IAA repressors. We also use microarray studies of elongating hypocotyls to show that a number of growth-associated processes are activated by auxin including gibberellin biosynthesis, cell wall reorganization and biogenesis, and others. Our studies indicate that GA biosynthesis is required for normal response to auxin in the hypocotyl but that the overall transcriptional auxin output consists of PIF-dependent and -independent genes. We propose that auxin acts independently from and interdependently with PIF and GA pathways to regulate expression of growth-associated genes in cell expansion.

Reliability investigations were conducted after GaN-based LEDs were stressed in seawater vapour. Multiple electrical, optical, and material analyses on the fine nanostructures of the LED were examined. Results indicate that dark spots on the surface and etching trenches observed on the cross section might damage the quantum well and degrade LED performance. Dissolved sodium ions might diffuse and punch through the quantum well and be responsible for these spots and trenches.