Leverage Variational Graph Representation for Model Poisoning on Federated Learning.

This article puts forth a new training data-untethered model poisoning (MP) attack on federated learning (FL). The new MP attack extends an adversarial variational graph autoencoder (VGAE) to create malicious local models based solely on the benign local models overheard without any access to the training data of FL. Such an advancement leads to the VGAE-MP attack that is not only efficacious but also remains elusive to detection. VGAE-MP attack extracts graph structural correlations among the benign local models and the training data features, adversarially regenerates the graph structure, and generates malicious local models using the adversarial graph structure and benign models' features. Moreover, a new attacking algorithm is presented to train the malicious local models using VGAE and sub-gradient descent, while enabling an optimal selection of the benign local models for training the VGAE. Experiments demonstrate a gradual drop in FL accuracy under the proposed VGAE-MP attack and the ineffectiveness of existing defense mechanisms in detecting the attack, posing a severe threat to FL.

O-GlcNAcylation: roles and potential therapeutic target for bone pathophysiology.

O-linked N-acetylglucosamine (O-GlcNAc) protein modification (O-GlcNAcylation) is a critical post-translational modification (PTM) of cytoplasmic and nuclear proteins. O-GlcNAcylation levels are regulated by the activity of two enzymes, O-GlcNAc transferase (OGT) and O­GlcNAcase (OGA). While OGT attaches O-GlcNAc to proteins, OGA removes O-GlcNAc from proteins. Since its discovery, researchers have demonstrated O-GlcNAcylation on thousands of proteins implicated in numerous different biological processes. Moreover, dysregulation of O-GlcNAcylation has been associated with several pathologies, including cancers, ischemia-reperfusion injury, and neurodegenerative diseases. In this review, we focus on progress in our understanding of the role of O-GlcNAcylation in bone pathophysiology, and we discuss the potential molecular mechanisms of O-GlcNAcylation modulation of bone-related diseases. In addition, we explore significant advances in the identification of O-GlcNAcylation-related regulators as potential therapeutic targets, providing novel therapeutic strategies for the treatment of bone-related disorders.

Accelerated dissemination of antibiotic resistant genes via conjugative transfer driven by deficient denitrification in biochar-based biofiltration systems.

Biofiltration systems harbored and disseminated antibiotic resistance genes (ARGs), when confronting antibiotic-contained wastewater. Biochar, a widely used environmental remediation material, can mitigate antibiotic stress on adjoining microbes by lowering the availability of sorbed antibiotics, and enhance the attachment of denitrifiers. Herein, bench-scale biofiltration systems, packed with commercial biochars, were established to explore the pivotal drivers affecting ARG emergence. Results showed that biofiltration columns, achieving higher TN removal and denitrification capacity, showed a significant decrease in ARG accumulation (p < 0.05). The relative abundance of ARGs (0.014 ± 0.0008) in the attached biofilms decreased to 1/5-folds of that in the control group (0.065 ± 0.004). Functional analysis indicated ARGs' accumulation was less attributed to ARG activation or horizontal gene transfer (HGT) driven by sorbed antibiotics. Most denitrifiers, like Bradyrhizobium, Geothrix, etc., were found to be enriched and host ARGs. Nitrosative stress from deficient denitrification was demonstrated to be the dominant driver for affecting ARG accumulation and dissemination. Metagenomic and metaproteomic analysis revealed that nitrosative stress promoted the conjugative HGT of ARGs mainly via increasing the transmembrane permeability and enhancing the amino acid transport and metabolism, such as cysteine, methionine, and valine metabolism. Overall, this study highlighted the risks of deficient denitrification in promoting ARG transfer and transmission in biofiltration systems and natural ecosystems.

Photonic delay reservoir computer based on ring resonator for reconfigurable microwave waveform generator.

To achieve an autonomously controlled reconfigurable microwave waveform generator, this study proposes and demonstrates a self-adjusting synthesis method based on a photonic delay reservoir computer with ring resonator. The proposed design exploits the ring resonator to configure the reservoir, facilitating a nonlinear transformation and providing delay space. A theoretical analysis is conducted to explain how this configuration addresses the challenges of microwave waveform generation. Considering the generalization performance of waveform generation, the simulations demonstrate the system's capability to produce six distinct representative waveforms, all exhibiting a highly impressive root mean square error (RMSE) of less than 1%. To further optimize the system's flexibility and accuracy, we explore the application of various artificial intelligence algorithms at the reservoir computer's output layer. Furthermore, our investigation delves deeply into the complexities of system performance, specifically exploring the influence of reservoir neurons and micro-ring resonator parameters on calculation performance. We also delve into the scalability of reservoirs, considering both parallel and cascaded arrangements.

Multiple-time scale integration method based on an interpolated potential energy surface for ab initio path integral molecular dynamics.

A new multiple-time scale integration method is presented that propagates ab initio path integral molecular dynamics (PIMD). This method uses a large time step to generate an approximate geometrical configuration whose energy and gradient are evaluated at the level of an ab initio method, and then, a more precise integration scheme, e.g., the Bulirsch-Stoer method or velocity Verlet integration with a smaller time step, is used to integrate from the previous step using the computationally efficient interpolated potential energy surface constructed from two consecutive points. This method makes the integration of PIMD more efficient and accurate compared with the velocity Verlet integration. A Nosé-Hoover chain thermostat combined with this new multiple-time scale method has good energy conservation even with a large time step, which is usually challenging in velocity Verlet integration for PIMD due to the very small chain mass when a large number of beads are used. The new method is used to calculate infrared spectra and free energy profiles to demonstrate its accuracy and capabilities.

Efficacy and safety of small-incision corneal intrastromal lenticule implantation for hyperopia correction: a systematic review and meta-analysis.

Purpose: To assess the efficacy and safety of intrastromal lenticule implantation for the treatment of hyperopia. Methods: A systematic search of PubMed, Web of Science, Embase, Cochrane Library, China National Knowledge Internet, and Wan Fang Database identified studies on small-incision intrastromal lenticule implantation for hyperopia correction until January 2023. The Joanna Briggs Institute (JBI) critical appraisal tool was used to assess the quality of the retrospective research, and the Methodological Index for Non-randomized Studies (MINORS) was used to assess the quality of the prospective research. This study included postoperative visual outcomes, corneal morphology, and biomechanical outcomes. Results: A total of 456 articles were identified, of which 10 were included in the meta-analysis. Ten single-arm studies involving 190 eyes were included. A meta-analysis demonstrated that corneal intrastromal lenticule implantation treatment significantly improved hyperopia. Uncorrected distance visual acuity (UDVA) significantly improved compared to the preoperative value (p = 0.027), corrected distance visual acuity showed no difference compared to the preoperative value (p = 0.27), and 87% eyes have no loss of one or more lines in the Snellen lines of CDVA (p < 0.00001). There was a significant difference between the spherical equivalent refractive (SE) and preoperative examination (p < 0.00001), 52% of eyes had ±0.5 diopters (D) postoperative SE (p < 0.00001), and 74% eyes had ±1.0 D postoperative SE (p < 0.00001). The central corneal thickness (CCT) increased by 72.68 µm compared to that preoperatively (p < 0.00001), and corneal curvature increased by 4.18D (p < 0.00001). The Q-value decreased by 0.82 (p < 0.00001), and higher-order aberration (HOA) decreased by 0.66 (p < 0.00001). Conclusion: Small-incision intrastromal lenticule implantation may be an effective solution for correcting hyperopia. The effect of improved vision is significant, but further exploration is needed for changes in corneal biomechanics and long-term safety.Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42023432343.

Cancer screening in hospitalized ischemic stroke patients: a multicenter study focused on multiparametric analysis to improve management of occult cancers.

Background/aims: The reciprocal promotion of cancer and stroke occurs due to changes in shared risk factors, such as metabolic pathways and molecular targets, creating a "vicious cycle." Cancer plays a direct or indirect role in the pathogenesis of ischemic stroke (IS), along with the reactive medical approach used in the treatment and clinical management of IS patients, resulting in clinical challenges associated with occult cancer in these patients. The lack of reliable and simple tools hinders the effectiveness of the predictive, preventive, and personalized medicine (PPPM/3PM) approach. Therefore, we conducted a multicenter study that focused on multiparametric analysis to facilitate early diagnosis of occult cancer and personalized treatment for stroke associated with cancer. Methods: Admission routine clinical examination indicators of IS patients were retrospectively collated from the electronic medical records. The training dataset comprised 136 IS patients with concurrent cancer, matched at a 1:1 ratio with a control group. The risk of occult cancer in IS patients was assessed through logistic regression and five alternative machine-learning models. Subsequently, select the model with the highest predictive efficacy to create a nomogram, which is a quantitative tool for predicting diagnosis in clinical practice. Internal validation employed a ten-fold cross-validation, while external validation involved 239 IS patients from six centers. Validation encompassed receiver operating characteristic (ROC) curves, calibration curves, decision curve analysis (DCA), and comparison with models from prior research. Results: The ultimate prediction model was based on logistic regression and incorporated the following variables: regions of ischemic lesions, multiple vascular territories, hypertension, D-dimer, fibrinogen (FIB), and hemoglobin (Hb). The area under the ROC curve (AUC) for the nomogram was 0.871 in the training dataset and 0.834 in the external test dataset. Both calibration curves and DCA underscored the nomogram's strong performance. Conclusions: The nomogram enables early occult cancer diagnosis in hospitalized IS patients and helps to accurately identify the cause of IS, while the promotion of IS stratification makes personalized treatment feasible. The online nomogram based on routine clinical examination indicators of IS patients offered a cost-effective platform for secondary care in the framework of PPPM. Supplementary Information: The online version contains supplementary material available at 10.1007/s13167-024-00354-8.

NEK2 affects the ferroptosis sensitivity of gastric cancer cells by regulating the expression of HMOX1 through Keap1/Nrf2.

NEK2 is a serine/threonine protein kinase that is involved in regulating the progression of various tumors. Our previous studies have found that NEK2 is highly expressed in gastric cancer and suggests that patients have a worse prognosis. However, its role and mechanism in gastric cancer are only poorly studied. In this study, we established a model of ferroptosis induced by RSL3 or Erastin in AGS cells in vitro, and konckdown NEK2, HOMX1, Nrf2 by siRNA. The assay kit was used to analyzed cell viability, MDA levels, GSH and GSSG content, and FeRhoNox™-1 fluorescent probe, BODIPY™ 581/591 C11 lipid oxidation probe, CM-H2DCFDA fluorescent probe were used to detected intracellular Fe2+, lipid peroxidation, and ROS levels, respectively. Calcein-AM/PI staining was used to detect the ratio of live and dead cells, qRT-PCR and Western blot were used to identify the mRNA and protein levels of genes in cells, immunofluorescence staining was used to analyze the localization of Nrf2 in cells, RNA-seq was used to analyze changes in mRNA expression profile, and combined with the FerrDb database, ferroptosis-related molecules were screened to elucidate the impact of NEK2 on the sensitivity of gastric cancer cells to ferroptosis. We found that inhibition of NEK2 could enhance the sensitivity of gastric cancer cells to RSL3 and Erastin-induced ferroptosis, which was reflected in the combination of inhibition of NEK2 and ferroptosis induction compared with ferroptosis induction alone: cell viability and GSH level were further decreased, while the proportion of dead cells, Fe2+ level, ROS level, lipid oxidation level, MDA level, GSSG level and GSSG/GSH ratio were further increased. Mechanism studies have found that inhibiting NEK2 could promote the expression of HMOX1, a gene related to ferroptosis, and enhance the sensitivity of gastric cancer cells to ferroptosis by increasing HMOX1. Further mechanism studies have found that inhibiting NEK2 could promote the ubiquitination and proteasome degradation of Keap1, increase the level of Nrf2 in the nucleus, and thus promote the expression of HMOX1. This study confirmed that NEK2 can regulate HMOX1 expression through Keap1/Nrf2 signal, and then affect the sensitivity of gastric cancer cells to ferroptosis, enriching the role and mechanism of NEK2 in gastric cancer.

Image Omics Nomogram Based on Incoherent Motion Diffusion-Weighted Imaging in Voxels Predicts ATRX Gene Mutation Status of Brain Glioma Patients.

This study aimed to construct an imaging genomics nomogram based on intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) to predict the status of the alpha thalassemia/mental retardation syndrome X-linked (ATRX) gene in patients with brain gliomas. We retrospectively analyzed routine MR and IVIM-DWI data from 85 patients with pathologically confirmed brain gliomas from January 2017 to May 2023. The data were divided into a training set (N=61) and a test set (N=24) in a 7:3 ratio. Regions of interest (ROIs) of brain gliomas, including the solid tumor region (rCET), edema region (rE), and necrotic region (rNec), were delineated using 3D-Slicer software and projected onto the D, D*, and f sequences. A total of 1037 features were extracted from each ROI, resulting in 3111 features per patient. Age was incorporated in the calculation of the Radscore, and a clinical-imaging genomics combined model was constructed, from which a nomogram graph was generated. Separate models were built for the D, D*, and f parameters. The AUC value of the D parameter model was 0.97 (95% CI: 0.93-1.00) in the training set and 0.91 (95% CI: 0.79-1.00) in the validation set, which was significantly higher than that of the D* parameter model (0.90, 0.82) and the f parameter model (0.89, 0.91). The imaging genomics nomogram based on IVIM-DWI can effectively predict the ATRX gene status of patients with brain gliomas, with the D parameter showing the highest efficacy.

Experimental investigation on the internal stress of bismuth-doped fiber and its effect on the noise figure of Bismuth-doped fiber amplifier.

The noise figure (NF) of a fiber amplifier is one of the key measures of amplification performance, which characterizes the quality of the amplified signal. Residual stresses are inevitably generated during the manufacturing process of optical fibers, and this can lead to changes in the refractive index (RI) distribution of the fiber. Further, the change in RI distribution causes the mode-field characteristics of the fiber to change as well, and this ultimately has an impact on the NF performance of the amplifier. However, until now, there have been fewer studies on the effect of residual stress on the NF of the fiber amplifiers. In this work, we took a commercial single-mode bismuth-doped fiber (BDF) as an example and used a self-developed stress test device to measure its residual stress and refractive index distribution and compare it with that of a passive fiber. We also comprehensively compared the distribution of residual stress and refractive index of the fiber at different pump powers and pump wavelengths. Finally, we performed numerical simulations of the bismuth-doped fiber amplifier (BDFA) based on the BDF under the theoretical mode field area and BDF after the expansion of the mode field area due to stresses to compare the NF performance. The results demonstrate that: the entire cross-section (core and cladding) of the BDF exhibits tensile stress (>0 MPa), where the residual stress at the core of the BDF is nearly 9.8 MPa higher than that of the passive fiber; The residual stress makes the mode-field area of the BDF expand by 26.7% compared with the theoretical values, which ultimately makes the NF of the BDFA rise from 4.6 dB to 4.7 dB; The stress at the BDF core is exacerbated by pump excitation, where it is elevated by about 26% and 5% compared to vacancy at 1240 nm and 1310 nm pumps, which is most likely attributed to thermal effects. Therefore, it is necessary to consider the effect of residual stresses in the fabrication of optical fibers to better achieve the radius of the expected indicators. This work contributes to the better development of O-band BDFAs, especially for pre-simulation of the actual performance of BDFAs with a practical reference.

Correlation analysis of vaginal flora and immune function Th1/Th2 imbalance in women with high-risk HPV infections in the female reproductive tract.

The purpose of this study was to analyze the correlation between vaginal flora and immune function Type 1 helper T cells/Type 2 helper T cells imbalance in females having HPV infections at high risk within the female reproductive tract. We selected 150 female patients who visited our hospital for reproductive tract inflammation between March 2019 and March 2021. They were divided into high-risk HPV-positive and high-risk HPV-negative groups according to the results of the HPV tests. Vaginal flora composition, density, diversity, and Th1/Th2 immune cell cytokine expression were assessed, and their correlations were analyzed. Compared to the HPV-negative group at high risk, the HPV-positive group at high risk exhibited significantly higher rates of Lactobacillius abnormalities, Chlamydia trachomatis and Mycoplasma urealyticum positivity(P<0.05). However, no statistically significant differences in the rates of Neisseria gonorrhoeae, bacterial vaginosis, mould, and trichomonad positivity were observed in both groups (P>0.05). The high-risk HPV-positive group displayed significantly higher rates of abnormal vaginal flora density and diversity compared to the HPV-negative group at high risk (P < 0.05). Compared to the HPV-negative group at high risk, the HPV-positive group at high risk exhibited significantly lower expression levels of Th1, Th1/Th2, IFN-γ, and IL-2 and higher expression levels of Th2, IL-4, and IL-10(P<0.05). Among patients having HPV infections at high risk, those with abnormal vaginal flora had lower expression levels of Th1, Th1/Th2, IFN-γ, and IL-2 and higher expression levels of Th2, IL-4, and IL-10 compared to those with normal vaginal flora, all of which were statistically significant(P<0.05). Vaginal flora dysbiosis was correlated with Th1/Th2 imbalance (P<0.05). Women with high-risk HPV infections in the female reproductive tract exhibit abnormal vaginal flora and immune function Th1/Th2 imbalance, characterized by a shift from Th1 to Th2. Moreover, there is a close correlation between vaginal flora dysbiosis and immune function Th1/Th2 imbalance.

Human pangenome analysis of sequences missing from the reference genome reveals their widespread evolutionary, phenotypic, and functional roles.

Nonreference sequences (NRSs) are DNA sequences present in global populations but absent in the current human reference genome. However, the extent and functional significance of NRSs in the human genomes and populations remains unclear. Here, we de novo assembled 539 genomes from five genetically divergent human populations using long-read sequencing technology, resulting in the identification of 5.1 million NRSs. These were merged into 45284 unique NRSs, with 29.7% being novel discoveries. Among these NRSs, 38.7% were common across the five populations, and 35.6% were population specific. The use of a graph-based pangenome approach allowed for the detection of 565 transcript expression quantitative trait loci on NRSs, with 426 of these being novel findings. Moreover, 26 NRS candidates displayed evidence of adaptive selection within human populations. Genes situated in close proximity to or intersecting with these candidates may be associated with metabolism and type 2 diabetes. Genome-wide association studies revealed 14 NRSs to be significantly associated with eight phenotypes. Additionally, 154 NRSs were found to be in strong linkage disequilibrium with 258 phenotype-associated SNPs in the GWAS catalogue. Our work expands the understanding of human NRSs and provides novel insights into their functions, facilitating evolutionary and biomedical researches.

RAF1 mutation leading to hypertrophic cardiomyopathy in a Chinese family with a history of sudden cardiac death: A diagnostic insight into Noonan syndrome.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is predominantly caused by mutations in sarcomeric genes. However, a subset of cases is attributed to genetic disorders unrelated to sarcomeric genes, such as Noonan syndrome (NS) and other RASopathies. In this study, we present a family with a history of sudden cardiac death (SCD) and focus on two adults with syndromic left ventricular hypertrophy (LVH). METHODS: Clinical evaluations, including echocardiography, were conducted to assess cardiac manifestations. Whole-exome sequencing was performed to identify potential genetic variants underlying syndromic LVH in the study participants. RESULTS: Whole-exome sequencing revealed a missense variant in the RAF1 gene, c.782C>T (p.Pro261Leu). This variant confirmed the diagnosis of NS in the affected individuals. CONCLUSION: The findings of this study underscore the importance of family history investigation and genetic testing in diagnosing syndromic LVH. By identifying the underlying genetic cause, clinicians can better understand the etiology of RAS-HCM and its association with SCD in young adults.

Targeting metabolic reprogramming in hepatocellular carcinoma to overcome therapeutic resistance: A comprehensive review.

Hepatocellular carcinoma (HCC) poses a heavy burden on human health with high morbidity and mortality rates. Systematic therapy is crucial for advanced and mid-term HCC, but faces a significant challenge from therapeutic resistance, weakening drug effectiveness. Metabolic reprogramming has gained attention as a key contributor to therapeutic resistance. Cells change their metabolism to meet energy demands, adapt to growth needs, or resist environmental pressures. Understanding key enzyme expression patterns and metabolic pathway interactions is vital to comprehend HCC occurrence, development, and treatment resistance. Exploring metabolic enzyme reprogramming and pathways is essential to identify breakthrough points for HCC treatment. Targeting metabolic enzymes with inhibitors is key to addressing these points. Inhibitors, combined with systemic therapeutic drugs, can alleviate resistance, prolong overall survival for advanced HCC, and offer mid-term HCC patients a chance for radical resection. Advances in metabolic research methods, from genomics to metabolomics and cells to organoids, help build the HCC metabolic reprogramming network. Recent progress in biomaterials and nanotechnology impacts drug targeting and effectiveness, providing new solutions for systemic therapeutic drug resistance. This review focuses on metabolic enzyme changes, pathway interactions, enzyme inhibitors, research methods, and drug delivery targeting metabolic reprogramming, offering valuable references for metabolic approaches to HCC treatment.

Insights into the roles of biochar pores toward alleviating antibiotic resistance genes accumulation in biofiltration systems.

Biofiltration systems would harbor and spread various antibiotic resistance genes (ARGs) when treating antibiotic micro-pollution, constituting a potential ecological risk. This study aimed to investigate the effects of biochar pores on ARG emergence and related microbial response mechanisms in bench-scale biofiltration systems. Results showed that biochar pores effectively reduced the absolute copies of the corresponding ARGs sul1 and sul2 by 54.1% by lowering the sorbed-SMX's bioavailability compared to non-porous anthracite. An investigation of antimicrobial resistomes revealed a considerable decrease in the abundance and diversity of ARGs and mobile gene elements. Metagenomic and metaproteomic analysis demonstrated that biochar pores induced the changeover of microbial defense strategy against SMX from blocking SMX uptake by EPS absorbing to SMX biotransformation. Microbial SOS response, antibiotic efflux pump, EPS secretion, and biofilm formation were decreased. Functions related to SMX biotransformation, such as sadABC-mediated transformation, xenobiotics degradation, and metabolism, were significantly promoted.

Microscale tissue engineering of liver lobule models: advancements and applications.

The liver, as the body's primary organ for maintaining internal balance, is composed of numerous hexagonal liver lobules, each sharing a uniform architectural framework. These liver lobules serve as the basic structural and functional units of the liver, comprised of central veins, hepatic plates, hepatic sinusoids, and minute bile ducts. Meanwhile, within liver lobules, distinct regions of hepatocytes carry out diverse functions. The in vitro construction of liver lobule models, faithfully replicating their structure and function, holds paramount significance for research in liver development and diseases. Presently, two primary technologies for constructing liver lobule models dominate the field: 3D bioprinting and microfluidic techniques. 3D bioprinting enables precise deposition of cells and biomaterials, while microfluidics facilitates targeted transport of cells or other culture materials to specified locations, effectively managing culture media input and output through micro-pump control, enabling dynamic simulations of liver lobules. In this comprehensive review, we provide an overview of the biomaterials, cells, and manufacturing methods employed by recent researchers in constructing liver lobule models. Our aim is to explore strategies and technologies that closely emulate the authentic structure and function of liver lobules, offering invaluable insights for research into liver diseases, drug screening, drug toxicity assessment, and cell replacement therapy.

Aqueous two-phase systems coupled with chemometrics-enhanced HPLC-DAD for simultaneous extraction and determination of flavonoids in honey.

In this study, an accurate, rapid, green, and environment friendly method for the extraction and quantitative analysis of flavonoids in honey was established by using the aqueous two-phase extraction combined with the chemometrics-assisted HPLC-DAD. The first purpose of this study was to extract seven flavonoids in five different types of honey using alcohol/salt aqueous two-phase system (ATPS). The system with 2.82 mL sodium citrate (30%), 1.58 mL water, and 3.10 mL isopropanol, showed the highest flavonoids extraction yields in the top phase (87.66-101.50%). Additionally, the three-way array of honey samples based on HPLC-DAD was decomposed mathematically by the alternating trilinear decomposition (ATLD) algorithm to obtain reasonable chromatograms, spectra, and concentration profiles for each analyte. Compared with the traditional solid-phase extraction method, the ATPS-ATLD-based method showed satisfactory spiked recoveries, lower limit of detection, and higher sensitivity, further verifying its accuracy and stability.

Acoustic quasi-periodic bioassembly based diverse stem cell arrangements for differentiation guidance.

Arrangement patterns and geometric cues have been demonstrated to influence cell function and fate, which calls for efficient and versatile cell patterning techniques. Despite constant achievements that mainly focus on individual cells and uniform cell patterns, simultaneously constructing cellular arrangements with diverse patterns and positional relationships in a flexible and contact-free manner remains a challenge. Here, stem cell arrangements possessing multiple geometries and structures are proposed based on powerful and diverse pattern-building capabilities of quasi-periodic acoustic fields, with advantages of rich patterns and structures and flexibility in structure modulation. Eight-fold waves' interference produces regular potentials that result in higher rotational symmetry and more complex arrangement of geometric units. Moreover, through flexible modulation of the phase relations among these wave vectors, a wide variety of cellular pattern units are arranged in this potential, such as circular-, triangular- and square-shape, simultaneously. It is proved that these diverse cellular patterns conveniently build human mesenchymal stem cell (hMSC) models, for research on the effect of cellular arrangement on stem cell differentiation. This work fills the gap of acoustic cell patterning in quasi-periodic patterns and shows promising potential in tissue engineering and regenerative medicine.

Photonic generation of triangular waveform with tunable symmetry based on channelized frequency synthesis.

A symmetry tunable triangular waveform photonic generator based on channelized frequency synthesis is proposed and studied. The generator adopts a multichannel system architecture and harmonic amplitude control algorithm to physically isolate each subchannel. In a single subchannel, quadrature phase shift keying modulation and coherent dual-wavelength balanced detection are used to realize optical upconversion and suppress mixing interference in the process of frequency conversion. Therefore, the model has the characteristics of a high-order Fourier series fitting tunable function waveform output. The analysis results show that the Fourier series harmonic coefficients can be adjusted flexibly by the multivariable joint regulation algorithm. The relationship between the variables is analyzed and discussed. The feasibility of the scheme is verified by optical simulation; when the rms error (RMSE)≤0.03, a 20%-80% tunable symmetry triangular waveform can be obtained.