Adaptation in Unstable Environments and Global Gene Losses: Small but Stable Gene Networks by the May-Wigner Theory.

Although gene loss is common in evolution, it remains unclear whether it is an adaptive process. In a survey of seven major mangrove clades that are woody plants in the intertidal zones of daily environmental perturbations, we noticed that they generally evolved reduced gene numbers. We then focused on the largest clade of Rhizophoreae and observed the continual gene set reduction in each of the eight species. A great majority of gene losses are concentrated on environmental interaction processes, presumably to cope with the constant fluctuations in the tidal environments. Genes of the general processes for woody plants are largely retained. In particular, fewer gene losses are found in physiological traits such as viviparous seeds, high salinity, and high tannin content. Given the broad and continual genome reductions, we propose the May-Wigner theory (MWT) of system stability as a possible mechanism. In MWT, the most effective solution for buffering continual perturbations is to reduce the size of the system (or to weaken the total genic interactions). Mangroves are unique as immovable inhabitants of the compound environments in the land-sea interface, where environmental gradients (such as salinity) fluctuate constantly, often drastically. Extending MWT to gene regulatory network (GRN), computer simulations and transcriptome analyses support the stabilizing effects of smaller gene sets in mangroves vis-à-vis inland plants. In summary, we show the adaptive significance of gene losses in mangrove plants, including the specific role of promoting phenotype innovation and a general role in stabilizing GRN in unstable environments as predicted by MWT.

APC mutations disrupt ß-catenin destruction complex condensates organized by Axin phase separation.

The Wnt/ß-catenin pathway is critical to maintaining cell fate decisions. Recent study showed that liquid-liquid-phase separation (LLPS) of Axin organized the ß-catenin destruction complex condensates in a normal cellular state. Mutations inactivating the APC gene are found in approximately 80% of all human colorectal cancer (CRC). However, the molecular mechanism of the formation of ß-catenin destruction complex condensates organized by Axin phase separation and how APC mutations impact the condensates are still unclear. Here, we report that the ß-catenin destruction complex, which is constructed by Axin, was assembled condensates via a phase separation process in CRC cells. The key role of wild-type APC is to stabilize destruction complex condensates. Surprisingly, truncated APC did not affect the formation of condensates, and GSK 3ß and CK1α were unsuccessfully recruited, preventing ß-catenin phosphorylation and resulting in accumulation in the cytoplasm of CRCs. Besides, we propose that the phase separation ability of Axin participates in the nucleus translocation of ß-catenin and be incorporated and concentrated into transcriptional condensates, affecting the transcriptional activity of Wnt signaling pathway.

New insights into the function of plant tannase with promiscuous acyltransferase activity.

Plant tannases (TAs) or tannin acyl hydrolases, a class of recently reported carboxylesterases in tannin-rich plants, are involved in the degalloylation of two important groups of secondary metabolites: flavan-3-ol gallates and hydrolyzable tannins. In this paper, we have made new progress in studying the function of tea (Camellia sinensis) (Cs) TA-it is a hydrolase with promiscuous acyltransferase activity in vitro and in vivo and promotes the synthesis of simple galloyl glucoses and flavan-3-ol gallates in plants. We studied the functions of CsTA through enzyme analysis, protein mass spectrometry, and metabolic analysis of genetically modified plants. Firstly, CsTA was found to be not only a hydrolase but also an acyltransferase. In the two-step catalytic reaction where CsTA hydrolyzes the galloylated compounds epigallocatechin-3-gallate or 1,2,3,4,6-penta-O-galloyl-ß-d-glucose into their degalloylated forms, a long-lived covalently bound Ser159-linked galloyl-enzyme intermediate is also formed. Under nucleophilic attack, the galloyl group on the intermediate is transferred to the nucleophilic acyl acceptor (such as water, methanol, flavan-3-ols, and simple galloyl glucoses). Then, metabolic analysis suggested that transient overexpression of TAs in young strawberry (Fragaria × ananassa) fruits, young leaves of tea plants, and young leaves of Chinese bayberry (Myrica rubra) actually increased the total contents of simple galloyl glucoses and flavan-3-ol gallates. Overall, these findings provide new insights into the promiscuous acyltransferase activity of plant TA.

High-Throughput Single-Entity Electrochemistry with Microelectrode Arrays.

We describe micro- and nanoelectrode array analysis with an automated version of the array microcell method (AMCM). Characterization of hundreds of electrodes, with diameters ranging from 100 nm to 2 µm, was carried out by using AMCM voltammetry and chronoamperometry. The influence of solvent evaporation on mass transport in the AMCM pipette and the resultant electrochemical response were investigated, with experimental results supported by finite element method simulations. We also describe the application of AMCM to high-throughput single-entity electrochemistry in measurements of stochastic nanoparticle impacts. Collision experiments recorded 3270 single-particle events from 671 electrodes. Data collection parameters were optimized to enable these experiments to be completed in a few hours, and the collision transient sizes were analyzed with a U-Net deep learning model. Elucidation of collision transient sizes by histograms from these experiments was enhanced due to the large sample size possible with AMCM.

Controllable non-uniformly distributed spiking cluster generation in broadband optoelectronic oscillator.

An approach to achieve controllable non-uniformly distributed spiking cluster generation is proposed and demonstrated based on an externally-triggered broadband optoelectronic oscillator (OEO). The theory of controlling the distribution of the spiking pulses in a spiking cluster is established. Based on the theory, the dynamic and the distribution characteristics are analyzed and revealed in the stable spiking oscillation state under different externally-injected trigger signal voltages. The peak-voltage envelop of the cluster and the interval of the spiking pulses are demonstrated to have an approximate negative linearity relationship with the externally-injected trigger signal voltage in both the numerical simulation and the experiment, where a square waveform, a trapezoidal waveform, a parabola waveform, and a half-sinusoidal waveform are used as the externally-injected trigger signals. The results indicate that the spiking pulse distribution in the generated spiking cluster can be well controlled through tuning the externally-injected trigger signal voltage. The proposed scheme can be utilized in spiking encoding and reservoir computing.

Phase-locked dual-frequency microwave signal generation in an optoelectronic oscillator based on frequency mixing mutual injection.

An approach to generating stable phase-locked dual-frequency microwave signals is proposed and demonstrated based on a dual-passband optoelectronic oscillator (OEO). Mode gain competition is broken by employing frequency mixing mutual injection effect to realize phase locking between the two oscillation signals, which is achieved by applying a single-tone signal to a microwave mixer in the OEO cavity. In addition, a dual-loop configuration with balanced detection is utilized to ensure a high side mode suppression ratio (SMSR) and ultra-low phase noise, which also enhances the stability of the generated signal. In the experiment, a phase-locked dual-frequency microwave signal at 9.9982 GHz and 10.1155 GHz is generated by using the proposed OEO scheme. The SMSR and the phase noise are 75 dB and -141 dBc/Hz@10 kHz, respectively. Additionally, the Allan deviation of the generated signal is in the order of 10-11@1 s. These parameters are superior to those based on the same OEO but with a single-loop configuration, which are also compared in detail.

Effect of different retention doses of ultrasound-guided polidocanol chemical ablation for benign cystic-solid thyroid nodules.

OBJECTIVE: To assess the influence of varying retention doses of ultrasound-guided polidocanol chemical ablation for benign cystic-solid thyroid nodules. METHODS: A retrospective study was conducted from December 2019 to January 2022, including 78 patients with benign cystic-solid thyroid nodules, of which 31 received polidocanol chemical ablation alone, 23 received polidocanol chemical plus thermal ablation, and 24 received open surgery. Patients who received polidocanol chemical ablation were assigned into groups based on the retention dose of polidocanol: 0 %, 10 %, 20 %, 30 %, and 50 %. Follow-ups were done at 1, 3, 6, and 12 months postoperatively. The volume of the nodules, postoperative complications, and recurrence of the nodules were examined before treatment and during follow-up visits. RESULTS: Total operation time and intraoperative bleeding volume for patients who received ablation were substantially lower than those for patients who received open surgery (P < 0.001). Among patients in the polidocanol chemical ablation group, volume shrinkage rate of thyroid nodules in the 10 % retention dose group was significantly lower than that in the 0 % retention dose group at 1, 3, and 6 months postoperatively (P < 0.05). The 30 % retention dose group had the highest nodule shrinkage rate (98.46 ± 1.55 %) at 12 months postoperatively, which was significantly higher than that in the 50 % retention dose group (P < 0.05). Among patients in the polidocanol chemical and thermal ablation group, the volume shrinkage rate of thyroid nodules in the 10 % and 30 % retention dose groups at 1 month postoperatively was significantly lower than that in the 0 % retention dose group (P < 0.05). Although volume shrinkage rate in the 20 % retention dose group after thermal ablation was higher than that in the 0 % retention dose group, the difference was not statistically significant (P > 0.05). In terms of adverse reactions, the incidence of hoarseness and coughing was higher in the open surgery group than in the polidocanol chemical ablation and polidocanol chemical and thermal ablation groups, but there was no significant difference (P > 0.05). CONCLUSION: Chemical ablation with polidocanol was safe and effective for therapy of benign cystic-solid thyroid nodules, and the optimal retention dose may be between 20 % and 30 %. Patients with poor efficacy from chemical ablation alone can receive safe and effective treatment through thermal ablation.

Self-Renewable Tag for Photostable Fluorescence Imaging of Proteins.

We report the development of a self-renewable tag (srTAG) for protein fluorescence imaging. srTAG leverages the "on-protein" fluorophore equilibrium between the fluorescent zwitterion and non-fluorescent spirocyclic form and the reversible fluorescence labeling to enable self-recovery of fluorescence after photobleaching. This small-sized srTAG allows 2-6 times longer imaging duration compared to other commonly used self-labeling tags and is compatible with fluorophores with different spectral properties. This study provides a new strategy for fine tuning of self-labeling tags.

High-resolution radar ranging based on the ultra-wideband chaotic optoelectronic oscillator.

A high-resolution radar ranging scheme is proposed and demonstrated based on the ultra-wideband chaotic optoelectronic oscillator (OEO). Through biasing the electro-optic intensity modulator near its minimum transmission point, high-dimensional chaotic signals with flat spectra and low time-delayed signatures can be generated in the OEO, which are favorable for increasing the ranging resolution and the confidentiality. In the experiment, the optimized broadband OEO generates a high-dimensional chaotic signal with a flat spectrum in the frequency range of 2 GHz to 16 GHz and a high permutation entropy of 0.9754. This chaotic signal is used to achieve multiple target ranging, where a ranging resolution of 1.4 cm is realized.

High-resolution real-time Fourier transform based on optical frequency comb injected frequency shifting loop.

A high-resolution real-time Fourier transform scheme is proposed and demonstrated based on injecting an optical frequency comb (OFC) into a frequency shifting loop (FSL). Through setting the frequency interval between neighboring teeth in the coherent OFC to be equal to an integer multiple of the frequency shift and also the free spectral range of the FSL, the number of the effective signal replicas from the FSL is increased by M times, where M is the tooth number of the OFC. Hence, it breaks the limitation on the number of round trips due to the gain saturation effect and the cumulative amplified spontaneous emission noise in the FSL under a single optical carrier injection, which greatly enhances the frequency resolution. In the experiment, a coherent three-tone optical carrier is injected into an FSL to realize real-time spectrum analysis, where the frequency resolution is enhanced by three times compared with that by using a single-tone optical carrier injection, i.e., from 60 kHz to 20 kHz.

Neuromorphic regenerative memory optoelectronic oscillator.

Neuromorphic spiking information processing based on neuron-like excitable effect has achieved rapid development in recent years due to its advantages such as ultra-high operation speed, programming-free implementation and low power consumption. However, the current physical platforms lack building blocks like compilers, logic gates, and more importantly, data memory. These factors become the shackles to construct a full-physical layer neural network. In this paper, a neuromorphic regenerative memory scheme is proposed based on a time-delayed broadband nonlinear optoelectronic oscillator (OEO), which enables reshaping and regenerating on-off keying encoding sequences. Through biasing the dual-drive Mach-Zehnder electro-optic modulator in the OEO cavity near its minimum transmission point, the OEO can work in excitable regime, where localized states are maintained for robust nonlinear spiking response. Both simulation and experiment are carried out to demonstrate the proposed scheme, where the simulation results and the experimental results fit in with each other. The proposed OEO-based neuromorphic regenerative memory scheme exhibits long-term response ability for short-term excitation, which shows an enormous application potential for high-speed neuromorphic information buffering, optoelectronic interconnection and computing.

Instantaneous bandwidth expansion of photonic sampling analog-to-digital conversion for linear frequency modulation waveforms based on up-sampling and fractional Fourier transform signal processing.

An approach to expanding the instantaneous bandwidth of a photonic sampling analog-to-digital converter (ADC) for receiving linear frequency modulation waveforms (LFMWs) is proposed and experimentally demonstrated based on up-sampling and filtering in the fractional Fourier domain. Through twice zero interpolation, the equivalent sampling rate is quadrupled, which also quadruples the nominal instantaneous bandwidth of the photonic sampling ADC. In addition, with the assistance of bandpass filtering in the fraction Fourier domain, the image signals and the harmonic distortions generated in the interpolation process are filtered out. As a result, the effective instantaneous bandwidth of the photonic sampling ADC is doubled. In the experiment, the instantaneous bandwidth of a photonic sampling ADC with a sampling rate of 5 GSa/s for receiving LFMWs is increased from 2.5 GHz to 5 GHz by using the proposed method. Input LFMWs within the frequency range of 24-27 GHz and 30-33 GHz, i.e., with an instantaneous bandwidth of 3 GHz, are digitized without frequency-domain aliasing. Besides, the ability of the proposed method to enhance the ranging accuracy in a broadband radar system is demonstrated. This method reduces the hardware complexity of the photonic sampling ADC for receiving broadband LFMWs in radar systems.

Time-delay signature suppression of the chaotic signal in a semiconductor laser based on optoelectronic hybrid feedback.

An approach to generating chaotic signals with low time-delay signatures (TDSs) from a semiconductor laser (SCL) is proposed and demonstrated based on optoelectronic hybrid feedback. Through using a chirped fiber Bragg grating (CFBG) to provide distributed feedback, a chaotic signal with a low TDS is generated from the SCL. With the assistance of the nonlinear optoelectronic feedback provided by a microwave photonic link, the relaxation oscillation effect in the SCL is effectively suppressed, and the periodicity of the oscillation is greatly weakened. Hence, the TDS of the generated chaotic signal from the SCL is further suppressed, and the effective bandwidth is enlarged. Both simulation and experiment are carried out to verify the feasibility of the proposed scheme to suppress the TDS. In the experiment, a chaotic signal with a large effective bandwidth of 12.93 GHz, an extremely high permutation entropy (PE) of 0.9983, and a low TDS of 0.04, is generated by using a CFBG with a dispersion coefficient of 22.33 ps/nm. This TDS value is at the same level as that obtained by using the SCL-based scheme relying solely on distributed feedback in a CFBG with a dispersion coefficient of 2000 ps/nm.

Pulse generation with programmable positions based on a phase-modulated optical frequency-shifting loop.

An approach to generating pulses with programmable positions is proposed and demonstrated based on a phase-modulated optical frequency-shifting loop (OFSL). By setting the OFSL to operate in the integer Talbot state, pulses are generated in the phase-locked positions, since the additional phase introduced by the electro-optic phase modulator (PM) in the OFSL is equal to an integer multiple of 2π in each round trip. Therefore, the pulse positions can be controlled and encoded by designing the driving waveform of the PM in a round-trip time. In the experiment, linear, round-trip, quadratic, and sinusoidal variations of pulse intervals are achieved by applying the corresponding driving waveforms to the PM. Pulse trains with coded pulse positions are also realized. In addition, the OFSL driven by waveforms with repetition rates equal to double and triple the free spectral range of the loop is also demonstrated. The proposed scheme paves a way to generate optical pulse trains with user-defined pulse positions, which can be used for such applications as compressed sensing and lidar.

Identification of fibrosis in hypertrophic cardiomyopathy: a radiomic study on cardiac magnetic resonance cine imaging.

OBJECTIVES: Hypertrophic cardiomyopathy (HCM) often requires repeated enhanced cardiac magnetic resonance (CMR) imaging to detect fibrosis. We aimed to develop a practical model based on cine imaging to help identify patients with high risk of fibrosis and screen out patients without fibrosis to avoid unnecessary injection of contrast. METHODS: A total of 273 patients with HCM were divided into training and test sets at a ratio of 7:3. Logistic regression analysis was used to find predictive image features to construct CMR model. Radiomic features were derived from the maximal wall thickness (MWT) slice and entire left ventricular (LV) myocardium. Extreme gradient boosting was used to build radiomic models. Integrated models were established by fusing image features and radiomic models. The model performance was validated in the test set and assessed by ROC and calibration curve and decision curve analysis (DCA). RESULTS: We established five prediction models, including CMR, R1 (based on the MWT slice), R2 (based on the entire LV myocardium), and two integrated models (ICMR+R1 and ICMR+R2). In the test set, ICMR+R2 model had an excellent AUC value (0.898), diagnostic accuracy (89.02%), sensitivity (92.54%), and F1 score (93.23%) in identifying patients with positive late gadolinium enhancement. The calibration plots and DCA indicated that ICMR+R2 model was well-calibrated and presented a better net benefit than other models. CONCLUSIONS: A predictive model that fused image and radiomic features from the entire LV myocardium had good diagnostic performance, robustness, and clinical utility. KEY POINTS: • Hypertrophic cardiomyopathy is prone to fibrosis, requiring patients to undergo repeated enhanced cardiac magnetic resonance imaging to detect fibrosis over their lifetime follow-up. • A predictive model based on the entire left ventricular myocardium outperformed a model based on a slice of the maximal wall thickness. • A predictive model that fused image and radiomic features from the entire left ventricular myocardium had excellent diagnostic performance, robustness, and clinical utility.

Electrochemically Reconstructed Vanadic Oxide-Doped Cobalt Pyrophosphate as an Electrocatalyst for the Oxygen Evolution Reaction.

More and more attention has been paid to the development of the efficient electrocatalysts for the oxygen evolution reaction (OER). Herein, a porous vanadic oxide-doped cobalt pyrophosphate electrocatalyst, namely V2O5-Co2P2O7, was exploited by using the electrochemical reconstruction method in the alkaline electrolyte and selecting a cobalt vanadium phosphate Co(H2O)4(VOPO4)2 as a precursor. The reconstructed vanadic oxide-doped cobalt pyrophosphate catalyst V2O5-Co2P2O7 exhibited efficient electrocatalytic activity for the OER in 1.0 M KOH, requiring a low overpotential of 199 mV at 10 mA cm-2, compared to the reported pyrophosphate electrocatalysts. The porous morphology and doping of vanadic oxide after electrochemical reconstruction were beneficial to enhance the electrocatalytic performance for the OER, through improving the surface area to bring in more accessibly active sites and regulating the electronic structures. The results provided a promising strategy to prepare the pyrophosphate electrocatalysts and improve the performance of the OER catalyst.

MiR-1284 suppresses the proliferation and migration of thyroid cancer.

To elucidate the role of microRNA-1284 (miR-1284) in the onset of thyroid cancer (TC) and its underlying mechanism. Differential expressions of miR-1284 in TC and thyroid tissues were detected. Regulatory effects of miR-1284 on proliferative, migratory, apoptotic potentials and cell cycle progression were assessed. In addition, miR-1284 levels in TC tissues and peripheral blood of TC patients were determined as well. Through collecting culture medium and exosomes of PTC cells, changes in miR-1284 levels were examined. MiR-1284 was downregulated in TC than normal thyroid tissues. Overexpression of miR-1284 attenuated proliferative and migratory potentials, but induced apoptosis in TPC-1 and FTC-133 cells. Moreover, overexpression of miR-1284 upregulated E-cadherin and downregulated N-cadherin in papillary TC (PTC) cells. MiR-1284 was downregulated in TC tissues, while its level in the peripheral blood of TC patients was upregulated. Besides, miR-1284 was upregulated in the culture medium and exosomes of PTC cells, which was reversed by Brefeldin A treatment. Overexpression of miR-1284 suppresses proliferative and migratory potentials and induces apoptosis in TC. Upregulated miR-1284 in the peripheral blood of TC patients may be derived from exosomes secreted by PTC cells.

Quantitative Relaxometry Assessment of Brain Microstructural Abnormality of Preschool Children With Autism Spectrum Disorder With Synthetic Magnetic Resonance Imaging.

OBJECTIVE: This study aimed to perform an assessment of brain microstructure in children with autism aged 2 to 5 years using relaxation times acquired by synthetic magnetic resonance imaging. MATERIALS AND METHODS: Thirty-four children with autism spectrum disorder (ASD) (ASD group) and 17 children with global developmental delay (GDD) (GDD group) were enrolled, and synthetic magnetic resonance imaging was performed to obtain T1 and T2 relaxation times. The differences in brain relaxation times between the 2 groups of children were compared, and the correlation between significantly changed T1/T2 and clinical neuropsychological scores in the ASD group was analyzed. RESULTS: Compared with the GDD group, shortened T1 relaxation times in the ASD group were distributed in the genu of corpus callosum (GCC) ( P = 0.003), splenium of corpus callosum ( P = 0.002), and right thalamus (TH) ( P = 0.014), whereas shortened T2 relaxation times in the ASD group were distributed in GCC ( P = 0.011), left parietal white matter ( P = 0.035), and bilateral TH (right, P = 0.014; left, P = 0.016). In the ASD group, the T2 of the left parietal white matter is positively correlated with gross motor (developmental quotient [DQ] 2) and personal-social behavior (DQ5), respectively ( r = 0.377, P = 0.028; r = 0.392, P = 0.022); the T2 of the GCC was positively correlated with DQ5 ( r = 0.404, P = 0.018); and the T2 of the left TH is positively correlated with DQ2 and DQ5, respectively ( r = 0.433, P = 0.009; r = 0.377, P = 0.028). All significantly changed relaxation values were not significantly correlated with Childhood Autism Rating Scale scores. CONCLUSIONS: The shortened relaxometry times in the brain of children with ASD may be associated with the increased myelin content and decreased water content in the brain of children with ASD in comparison with GDD, contributing the understanding of the pathophysiology of ASD. Therefore, the T1 and T2 relaxometry may be used as promising imaging markers for ASD diagnosis.

Time-domain convolution model for studying oscillation dynamics in an injection-locked optoelectronic oscillator.

A time-domain convolution model is proposed to study the oscillation dynamics in the injection-locked optoelectronic oscillator (OEO). The model has the ability to calculate multiple characteristics of the oscillation signal, such as the spectrum and the phase noise. Based on the model, the injection locking, the frequency pulling and the asymmetrical spectrum generation phenomena are numerically simulated in success. The simulation results fit in with the experimental results, indicating that the proposed model accurately describes the oscillation dynamics in the injection-locked OEO. In addition, the building-up process of the oscillation signal in the OEO is simulated. Alternating appearance of the sidebands on both sides of the primary oscillation mode is observed for the first time in the asymmetrical spectrum generation. This model is a powerful tool to study the oscillation dynamics in the injection-locked OEO.

The Functional Characterization of Carboxylesterases Involved in the Degradation of Volatile Esters Produced in Strawberry Fruits.

Volatile ester compounds are important contributors to the flavor of strawberry, which affect consumer preference. Here, the GC-MS results showed that volatile esters are the basic aroma components of strawberry, banana, apple, pear, and peach, and the volatile esters were significantly accumulated with the maturation of strawberry fruits. The main purpose of this study is to discuss the relationship between carboxylesterases (CXEs) and the accumulation of volatile ester components in strawberries. FaCXE2 and FaCXE3 were found to have the activity of hydrolyzing hexyl acetate, Z-3-hexenyl acetate, and E-2-hexenyl acetate to the corresponding alcohols. The enzyme kinetics results showed that FaCXE3 had the higher affinity for hexyl acetate, E-2-hexenyl acetate, and Z-3-hexenyl acetate compared with FaCXE2. The volatile esters were mainly accumulated at the maturity stages in strawberry fruits, less at the early stages, and the least during the following maturation stages. The expression of FaCXE2 gradually increased with fruit ripening and the expression level of FaCXE3 showed a decreasing trend, which suggested the complexity of the true function of CXEs. The transient expression of FaCXE2 and FaCXE3 genes in strawberry fruits resulted in a significantly decreased content of volatile esters, such as Z-3-hexenyl acetate, methyl hexanoate, methyl butyrate, and other volatile esters. Taken together, FaCXE2 and FaCXE3 are indeed involved in the regulation of the synthesis and degradation of strawberry volatile esters.