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Abstract Obesity, a surging global health challenge, necessitates effective, accessible and innovative therapeutic models. Here we develop a spatiotemporally controllable microneedle (MN) drug delivery platform for sono-gene therapy to fight obesity. The platform delivers the methoxy polyethylene glycol-polyethyleneimine (mPEG-PEI) modified metal-organic frameworks (MOFs) sonosensitizer and the clustered regularly interspaced short palindromic repeats-activating (CRISPRa)/CRISPRa-uncoupling protein 1 (UCP1) system intradermally to adipocytes. Overall, this therapy platform is capable of achieving two major strategies of “annihilation” and “countermeasure”: one is to kill redundant white adipocytes by sonodynamic therapy, and the other is to promote the browning of white adipocytes through the controllable release of CRISPRa-UCP1 system and sonodynamic effect. Obese male mice treated with this sono-gene therapy shows significant ameliorate in glucose tolerance and insulin sensitivity, successfully achieves weight loss and restrains weight rebound. This study may enable a standard treatment paradigm for sono-gene therapy of obesity and other metabolic diseases.

Abstract Cancer remains a formidable global health challenge, necessitating innovative therapeutic approaches to enhance treatment efficacy and reduce adverse effects. The traditional Chinese medicine (TCM), as an embodiment of ancient wisdom, has been validated to regulate the holistic human capacity against both internal and external “evils” in accordance with TCM principles. Therefore, it stands to reason to integrate TCM into current cancer therapy paradigms, such as chemotherapy, immunotherapy, and targeted therapy. This strategy conceptually intends to circumvent the inevitable side effects derived from present treatment, alleviate the discomfort, mollify the detrimental mood and synergize tumoricidal effects of distinct approaches. However, it is still vague whether TCM exert favorable function in cancer treatment. Therefore, it is imperative to retrieve and compile the existing literature on TCM in the realm of cancer, followed by a comprehensive recapitulation and synthesis of its core findings. Recently, with the advancement of contemporary biologic and medical theory and technology, it has become both feasible and imperative to elucidate the molecular signaling mechanisms and cellular biology underlying TCM. Specifically, leveraging TCM pharmaceutic components can not only directly impact tumor biology at the molecular level, but regulate the tumor immune environment through distinct pathways. Additionally, the administration of external TCM treatments such as acupuncture and moxibustion also demonstrates beneficial effects in cancer patients. Through comprehensive analysis, we demonstrated that TCM not only potentially increases the efficacy of conventional cancer treatments, but also significantly mitigates their toxic side effects, thereby prolonging patients’ prognosis and improving their living quality. Furthermore, we have underscored the challenges and prospects associated with the integration of TCM into contemporary oncological practices, placing particular emphasis on the imperative for rigorous clinical trials and molecular investigations to substantiate the efficacy and safety of these combined therapeutic approaches. This synthesis aims to pave the way for a more integrated approach to cancer treatment rooted in both traditional wisdom and cutting-edge science.

Abstract The rapid development of internet of things (IoT) urgently needs edge miniaturized computing devices with high efficiency and low-power consumption. In-sensor computing has emerged as a promising technology to enable in-situ data processing within the sensor array. Here, we report an optoelectronic array for in-sensor computing by integrating photodiodes (PDs) with resistive random-access memories (RRAMs). The PD-RRAM unit cell exhibits reconfigurable optoelectronic output and photo-responsivity by programming RRAMs into different resistance states. Furthermore, a 3 × 3 PD-RRAM array is fabricated to demonstrate optical image recognition, achieving a universal architecture with ultralow latency and low power consumption. This study highlights the great potential of the PD-RRAM optoelectronic array as an energy-efficient in-sensor computing primitive for future IoT applications.

Abstract Background Malignant esophageal mediastinal fistula is a severe complication that occurs in both the advanced stages of esophageal cancer and after radiotherapy for esophageal cancer. Esophageal mediastinal fistula is very susceptible to complications such as mediastinitis and mediastinal abscess, resulting in a significantly elevated mortality rate for patients. We reported a rare case of esophageal mediastinal fistula after immunotherapy for non-small cell lung cancer (NSCLC). Case Presentation A 74-year-old male patient with NSCLC was hospitalized in July 2023. About one week after Tislelizumab immunotherapy, the patient suddenly developed high fever accompanied by coughing and choking on water, chest tightness, shortness of breath, and hemoptysis. Following the completion of bronchial artery computed tomography angiography (CTA), imaging suggested the presence of esophageal mediastinal fistula. We opted for a conservative medical treatment instead of surgery. The patient was discharged without any complications. Conclusions This is the first case of NSCLC accompanied by an esophageal mediastinal fistula after treatment with tislelizumab. The occurrence of malignant esophageal mediastinal fistula is very uncommon and poses a high level of hazard. In addition, this paper provides a concise overview of cases of lung cancer complicated with esophageal fistula in the past 10 years. It offers valuable insights for diagnosis and treatment, serving as a resource for clinicians.

Abstract Background The incidence of musculoskeletal diseases is increasing in clinical practice, leading to a growing demand for rehabilitation medicine. However, education in musculoskeletal education is lacking in the training of physical medicine and rehabilitation students. This study aims to evaluate the impact of musculoskeletal education on medical students’ learning of rehabilitation medicine and analyze the correlation between influencing factors and education. Objectives The primary objective of this study is to evaluate the impact of musculoskeletal education on medical students’ learning of rehabilitation medicine. Furthermore, the authors aim to analyze the correlation between various influencing factors and the effectiveness of this education, with the goal of informing future educational interventions and enhancing student outcomes. Methods A comprehensive search was conducted across the Pubmed, Ovid, and Cochrane Central Register of Controlled Trials (CENTRAL) databases for relevant articles published from January 2012 to September 2024. The search focused on medical students as the research subjects and musculoskeletal education as the intervention method. Both randomized controlled trials (RCTs) and non-randomized controlled trials (non-RCTs) were included. The selected studies underwent a systematic review, and meta-analysis was performed using R 3.4.4 software. Results After a thorough search, 41 studies were included. The retrospective study indicated that the most common impacts were knowledge acquisition, self-confidence, and satisfaction. The subsequent meta-analysis revealed significant increases in students’ knowledge acquisition [standardized mean differences (SMD) = 2.15, 95% confidence interval [CI] (1.36, 2.94), I 2 = 97%, random effect model] and self-confidence [SMD = 5.81, 95% CI (2.88, 8.75), I 2 = 97%, random effect model]. Compared with the general teaching control group, the knowledge acquisition of students in the observation group improved [SMD = 0.25, 95% CI (0.00, 0.51), I 2 = 83%, in the random effect model]; However, no significant difference in satisfaction occurred [SMD = 0.27, 95% CI (-0.47, 1.01), P > 0.05, I 2 = 89%, in the random effects model]. Conclusion Musculoskeletal education primarily impacts knowledge acquisition self-confidence, and satisfaction among physical medicine and rehabilitation students. The meta-analysis further establishes that musculoskeletal education significantly enhances knowledge acquisition and confidence in these students. Trial registration CRD42024563899 (completed on July 17, 2024).

Abstract Sonogenetics is an innovative technology that integrates ultrasound with genetic editing to precisely modulate cellular activities in a non‐invasive manner. This method entails introducing and activating mechanosensitive channels on the cell membrane of specific cells using gene delivery vectors. When exposed to ultrasound, these channels can be manipulated to open or close, thereby impacting cellular functions. Sonogenetics is currently being used extensively in the treatment of various chronic diseases, including Parkinson's disease, vision restoration, and cancer therapy. This paper provides a comprehensive review of key components of sonogenetics and focuses on evaluating its prospects and potential challenges in the treatment of chronic disease.

This paper presents a wide-bandwidth back-illuminated modified uni-traveling-carrier photodiode (MUTC-PD) packaged with standard WR-5 rectangular waveguide for high-speed wireless communications. With optimized epitaxy structure and coplanar waveguide electrodes, the fabricated 4-μm-diameter PD exhibits ultra-flat frequency response and high saturation power. Integrated passive circuits including low-loss bias-tee and E-plane probe are designed to package the PD into a compact module with waveguide output. The packaged PD module has demonstrated a flat frequency response with fluctuations within ±2.75 dB over a broadband of 140–220 GHz and a high saturated output power of −7.8 dBm (166 μW) at 140 GHz. For wireless communication applications, the packaged PD is used to implement 1-m free space transmission at carrier frequencies of 150.5 and 210.5 GHz, with transmission rates of 75 and 90 Gbps, respectively.

Abstract Background Immunotherapies effectively treat human malignancies, but the low response and resistance are major obstacles. Neoantigen is an emerging target for tumor immunotherapy that can enhance anti-tumor immunity and improve immunotherapy. Aberrant alternative splicing is an important source of neoantigens. HNRNPA1, an RNA splicing factor, was found to be upregulated in the majority of tumors and play an important role in the tumor immunosuppressive microenvironment. Methods Whole transcriptome sequencing was performed on shHNRNPA1 SKOV3 cells and transcriptomic data of shHNRNPA1 HepG2, MCF-7M, K562, and B-LL cells were downloaded from the GEO database. Enrichment analysis was performed to elucidate the mechanisms underlying the activation of anti-tumor immunity induced by HNRNPA1 knockdown. mRNA alternative splicing was analyzed and neoantigens were predicted by JCAST v.0.3.5 and Immune epitope database. The immunogenicity of candidate neoantigens was calculated by Class I pMHC Immunogenicity and validated by the IFN-γ ELISpot assay. The effect of shHNRNPA1 on tumor growth and immune cells in vivo was evaluated by xenograft model combined with immunohistochemistry. Results HNRNPA1 was upregulated in a majority of malignancies and correlated with immunosuppressive status of the tumor immune microenvironment. Downregulation of HNRNPA1 could induce the activation of immune-related pathways and biological processes. Disruption of HNRNPA1 resulted in aberrant alternative splicing events and generation of immunogenic neoantigens. Downregulation of HNRNPA1 inhibited tumor growth and increased CD8+ T cell infiltration in vivo. Conclusion Our study demonstrated that targeting HNRNPA1 could produce immunogenic neoantigens that elicit anti-tumor immunity by inducing abnormal mRNA splicing. It suggests that HNRNPA1 may be a potential target for immunotherapy.

Abstract Objectives To evaluate the agreement between quantitative ultrasound system fat fraction (USFF) and proton magnetic resonance spectroscopy (1H-MRS) and the diagnostic value of USFF in assessing metabolic-associated fatty liver disease (MAFLD). Methods The participants with or suspected of MAFLD were prospectively recruited and underwent 1H-MRS, USFF, and controlled attenuation parameter (CAP) measurements. The correlation between USFF and 1H-MRS was assessed using Pearson correlation coefficients. The USFF diagnostic performance for different grades of steatosis was evaluated using receiver operating characteristic curve analysis (ROC) and was compared with CAP, visual hepatic steatosis grade (VHSG). Results A total of 113 participants (mean age 44.79 years ± 13.56 (SD); 71 males) were enrolled, of whom 98 (86.73%) had hepatic steatosis (1H-MRS ≥ 5.56%). USFF showed a good correlation (Pearson r = 0.76) with 1H-MRS and showed a linear relationship, which was superior to the correlation between CAP and 1H-MRS (Pearson r = 0.61). The USFF provided high diagnostic performance for different grades of hepatic steatosis, with ROC from 0.84 to 0.98, and the diagnostic performance was better than that of the CAP and the VHSG. The cut-off values of the USFF were different for various grades of steatosis, and the cut-off values for S1, S2, and S3 were 12.01%, 19.98%, and 22.22%, respectively. Conclusions There was a good correlation between USFF and 1H-MRS. Meanwhile, USFF had good diagnostic performance for hepatic steatosis and was superior to CAP and VHSG. USFF represents a superior method for noninvasive quantitative assessment of MAFLD. Critical relevance statement Quantitative ultrasound system fat fraction (USFF) accurately assesses liver fat content and has a good correlation with magnetic resonance spectroscopy (1H-MRS) for the assessment of metabolic-associated fatty liver disease (MAFLD), as well as for providing an accurate quantitative assessment of hepatic steatosis. Key Points Current diagnostic and monitoring modalities for metabolic-associated fatty liver disease have limitations. USFF correlated well with 1H-MRS and was superior to the CAP. USFF has good diagnostic performance for steatosis, superior to CAP and VHSG. Graphical Abstract

ObjectiveThis study aimed to characterize the differences in neural function among patients with different functional abilities 2 years after anterior cruciate ligament reconstruction (ACLR).DesignResting-state functional magnetic resonance imaging was performed to obtain blood-oxygen-level-dependent values for ACLR returned to sports coper participants (CP), non-coper participants (NP), and healthy controls (HC). The amplitude of low-frequency fluctuations (ALFF) and regional homogeneity (ReHo) calculated changes in the standard frequency band (SFB) (0.01–0.08 Hz), Slow4 (0.027–0.073 Hz), and Slow5 (0.01–0.027 Hz). Clinical correlations were investigated.ResultsThe right cerebellum_8 and bilateral putamen in SFB, while the right cerebellum_crus2 and left putamen in Slow5 were higher in CP than in NP. The ALLF values of the bilateral putamen in Slow4 were increased, while the right parietal lobule in Slow4 and left upper temporal pole in Slow5 were lower in CP than in HC. The ReHo values in the CP group in the right cerebellum_crus2 was higher than that in the NP group in Slow5 (voxel p

Micro-scale light-emitting diodes (micro-LEDs) have received widespread attention in recent years for applications in display and optical communication. Compared with conventional quantum well active regions, quantum dots (QDs) can increase the carrier concentration at the same current density, which is beneficial for improving the efficiency and bandwidth of LEDs at low current densities. This is exactly what micro-LEDs need for display and communication applications. In this Perspective, we give a general introduction to InGaN QDs and provide an overview of the growth of InGaN QDs by metal-organic chemical vapor deposition. We then discuss the advances in green and red micro-LEDs based on InGaN QDs for display applications. This is followed by recent progress on high-speed blue micro-LEDs, which have great potential for use in chip-to-chip optical interconnections. Finally, we address the remaining challenges for a further improvement in InGaN QD-based micro-LEDs.

IntroductionThe incidence of hemiplegia caused by stroke is high. In particular, lower limb dysfunction affects the daily activities of patients, and lower limb robotic devices have been proposed to provide rehabilitation therapy to improve balance function in this patient population.ObjectiveTo assess the effectiveness of the LiteStepper® unilateral lower limb exoskeleton (ULLE) combined with conventional treatment for balance function training in patients with post-stroke hemiplegia.MethodsThis multicenter randomized controlled trial, conducted in the convalescent rehabilitation ward of four hospitals, involved 92 patients in their post-stroke phase. Participants were randomized into an experimental group (EG) or a conventional group (CG). The EG adopted the LiteStepper® ULLE combined with conventional treatment for 21 days. The CG underwent a standard daily rehabilitation routine for 21 days. The Berg Balance Scale (BBS), Functional Ambulation Category scale (FAC), 6-min walk test (6MWT), and Barthel Index (Barthel) were used for evaluations before and after 21 days of rehabilitative training.ResultsThe BBS scores in EG was significantly elevated compared to CG, exhibiting a profound statistical difference (P< 0.0001). Notably, these disparities persisted at both day 21 (P < 0.0001) and day 14 (P < 0.0047) post-intervention, underscoring the efficacy of the treatment in the EG. The EG demonstrated a markedly greater improvement in BBS scores from pre-rehabilitation to 21 days post-training, significantly outperforming the CG. Furthermore, at both day 14 and day 21, functional assessments including the FAC, 6MWT, and Barthel revealed improvements in both groups. However, the improvements in the EG were statistically significant compared to the CG at both time points: day 14 (FAC, P = 0.0377; 6MWT, P = 0.0494; Barthel, P = 0.0225) and day 21 (FAC, P = 0.0015; 6MWT, P = 0.0005; Barthel, P = 0.0004). These findings highlight the superiority of the intervention in the EG in enhancing functional outcomes. Regarding safety, the analysis revealed a solitary adverse event (AEs) related to the LiteStepper®ULLE device during the study period, affirming the combination therapy’s safety profile when administered alongside conventional balance training in post-stroke hemiplegic patients. This underscores the feasibility and potential of incorporating LiteStepper®ULLE into rehabilitation protocols for this patient population.Discussion and significanceThe LiteStepper® ULLE combined with conventional treatment is effective and safe for balance function training in patients with post-stroke hemiplegia.

The widespread distribution of medical images in smart healthcare systems will cause privacy concerns. The unauthorized sharing of decrypted medical images remains uncontrollable, though image encryption can discourage privacy disclosure. This research proposes a double-level security scheme for medical images to overcome this problem. The proposed joint encryption and watermarking scheme is based on singular-value decomposition (SVD) and chaotic maps. First, three different random sequences are used to encrypt the LL subband in the discrete wavelet transform (DWT) domain; then, HL and LH sub-bands are embedded with watermark information; in the end, we obtain the watermarked and encrypted image with the inverse DWT (IDWT) transform. In this study, SVD is used for watermarking and encryption in the DWT domain. The main originality is that decryption and watermark extraction can be performed separately. Experimental results demonstrate the superiority of the proposed method in key spaces (10225), PSNR (76.2543), and UACI (0.3329). In this implementation, the following key achievements are attained. First, our scheme can meet requests of different security levels. Second, encryption and watermarking can be performed separately. Third, the watermark can be detected in the encrypted domain. Thus, experiment results and security analysis demonstrate the effectiveness of the proposed scheme.

Abstract Therapeutic mRNA vaccines have become powerful therapeutic tools for severe diseases, including infectious diseases and malignant neoplasms. mRNA vaccines encoding tumor‐associated antigens provide unprecedented hope for many immunotherapies that have hit the bottleneck. However, the application of mRNA vaccines is limited because of biological instability, innate immunogenicity, and ineffective delivery in vivo. This study aims to construct a novel mRNA vaccine delivery nanosystem to successfully co‐deliver a tumor‐associated antigen (TAA) encoded by the Wilms' tumor 1 (WT1) mRNA. In this system, named PSB@Nb1.33C/mRNA, photosynthetic bacteria (PSB) efficiently delivers the iMXene‐WT1 mRNA to the core tumor region using photo‐driven and hypoxia‐driven properties. The excellent photothermal therapeutic (PTT) properties of PSB and 2D iMxene (Nb1.33C) trigger tumor immunogenic cell death, which boosts the release of the WT1 mRNA. The released WT1 mRNA is translated, presenting the TAA and amplifying immune effect in vivo. The designed therapeutic strategy demonstrates an excellent ability to inhibit distant tumors and counteract postsurgical lung metastasis. Thus, this study provides an innovative and effective paradigm for tumor immunotherapy, i.e., photo‐immunogene cancer therapy, and establishes an efficient delivery platform for mRNA vaccines, thereby opening a new path for the wide application of mRNA vaccines.

Abstract Mitogen‐activated protein kinase‐activated protein kinase 2 (MK2) emerges as a pivotal target in developing anti‐cancer therapies. The limitations of ATP‐competitive inhibitors, due to insufficient potency and selectivity, underscore the urgent need for a covalent irreversible MK2 inhibitor. Our initial analyses of The Cancer Genome Atlas database revealed MK2's overexpression across various cancer types, especially those characterized by inflammation, linking it to poor prognosis and highlighting its significance. Investigating MK2's kinase domain led to the identification of a unique cysteine residue, enabling the creation of targeted covalent inhibitors. Compound 11 was developed, demonstrating robust MK2 inhibition (IC50 = 2.3 nM) and high selectivity. It binds irreversibly to MK2, achieving prolonged signal suppression and reducing pathological inflammatory cytokines in macrophages. Furthermore, compound 11 or MK2 knockdown can inhibit the tumor‐promoting macrophage M2 phenotype in vitro and in vivo. In macrophage‐rich tumor model, compound 11 notably slowed growth in a dose‐dependent manner. These findings support MK2 as a promising anticancer target, especially relevant in cancers fueled by inflammation or dominated by macrophages, and provide compound 11 serving as an invaluable chemical tool for exploring MK2's functions.

Abstract Background The widespread utilization of chest High-resolution Computed Tomography (HRCT) has prompted detection of pulmonary ground-glass nodules (GGNs) in otherwise asymptomatic individuals. We aimed to establish a simple clinical risk score model for assessing GGNs based on HRCT. Methods We retrospectively analyzed 574 GGNs in 574 patients undergoing HOOK-WIRE puncture and pulmonary nodule surgery from January 2014 to November 2018. Clinical characteristics and imaging features of the GGNs were assessed. We analyzed the differences between malignant and benign nodules using binary logistic regression analysis and constructed a simple risk score model, the VBV Score, for predicting the malignancy status of GGNs. Then, we validated this model via other 1200 GGNs in 1041 patients collected from three independent clinical centers in 2022. Results For the exploratory phase of this study, out of the 574 GGNs, 481 were malignant and 93 were benign. Vacuole sign, air bronchogram, and intra-nodular vessel sign were important indicators of malignancy in GGNs. Then, we derived a VBV Score = vacuole sign + air bronchogram + intra-nodular vessel sign, to predict the malignancy of GGNs, with a sensitivity, specificity, and accuracy of 95.6%, 80.6%, and 93.2%, respectively. We also validated it on other 1200 GGNs, with a sensitivity, specificity, and accuracy of 96.0%, 82.6%, and 95.0%, respectively. Conclusions Vacuole sign, air bronchogram, and intra-nodular vessel sign were important indicators of malignancy in GGNs. VBV Score showed good sensitivity, specificity, and accuracy for differentiating benign and malignant pulmonary GGNs.

Receptor-interacting protein kinase 2 (RIPK2) is an essential protein kinase mediating signal transduction by NOD1 and NOD2, which play an important role in regulating immune signalling. In this study, we designed and synthesised a novel series of 4-aminoquinoline-based derivatives as RIPK2 inhibitors. In vitro, compound 14 exhibited high affinity (IC50 = 5.1 ± 1.6 nM) and excellent selectivity to RIPK2 showing in a dendrogram view of the human kinome phylogenetic tree. Bearing favourable lipophilicity and eligible lipophilic ligand efficiency (LipE), compound 14 was selected to investigate cellular anti-inflammatory effect and was identified as a potent inhibitor to reduce the secretion of MDP-induced TNF-α with a dose-dependent manner. Moreover, compound 14 showed moderate stability in human liver microsome. Given these promising results, compound 14 could serve as a favourable inhibitor of RIPK2 for further physiological and biochemical research so as to be used in therapeutic treatment.

Abstract Spintronic terahertz (THz) emitters (STEs) based on magnetic heterostructures have emerged as promising THz sources. However, it is still a challenge to achieve a higher intensity STE to satisfy all kinds of practical applications. Herein, we report a STE based on Pt0.93(MgO)0.07/CoFeB nanofilm by introducing dispersed MgO impurities into Pt, which reaches a 200% intensity compared to Pt/CoFeB and approaches the signal of 500 μm ZnTe crystal under the same pump power. We obtain a smaller spin diffusion length of Pt0.93(MgO)0.07 and an increased thickness-dependent spin Hall angle relative to the undoped Pt. We also find that the thickness of a Pt layer leads to a drastic change in the interface role in the spintronic THz emission, suggesting that the underlying mechanism of THz emission enhancement is a combined effect of enhanced bulk spin hall angle and the interfacial skew scattering by MgO impurities. Our findings demonstrate a simple way to realize high-efficiency, stable, advanced spintronic THz devices.

The aft-body mounted inlet of a hypersonic vehicle has garnered attention for its potential to shorten the propulsion system. This study aims to explore the influence of compression direction on the performance of the hypersonic inlet attached to the vehicle’s aft body. To achieve this objective, a simplified, integrated model of the body and two-dimensional inlet was developed and evaluated using numerical simulation techniques. The study conducted a comparative analysis of the overall and starting performance between inverted and normal inlet layouts while ensuring uniformity in inlet configuration and installation location. The results indicated that the inverted layout surpassed the normal layout in terms of airflow capture capabilities, with an 8.24% higher mass flow rate. However, the inverted inlet layout exhibited an 11.46% reduction in total pressure recovery performance compared to the normal layout. Additionally, the study found that the inverted inlet layout demonstrated a self-starting Mach number 1.62 lower than that of the normal inlet layout. This difference stemmed primarily from the pressure gradient on the body surface induced by the incident shock wave of the inverted inlet, which enhanced starting performance by eliminating low-energy flow near the wall.

Abstract With the CoO2 slabs consisting of Co4O4 cubane structure, layered NaxCoO2 are considered promising candidates for oxygen evolution reaction (OER) in alkaline media given their earth‐abundant and structural advantages. However, due to the strong adsorption of intermediates on the large basal planes, NaxCoO2 cannot meet the activity demands. Here, a novel one‐pot synthesis strategy is proposed to realize the high solubility of iron in NaxCoO2 in an air atmosphere. The optimist Na0.6Co0.9Fe0.1O2 exhibits enhanced OER activity compared to their pristine and other reported Fe‐doped NaxCoO2 counterparts. Such an enhancement is mainly ascribed to the abundant active sites on the activated basal planes and the participation of oxidized oxygen as active sites independently, which breaks the scaling relationship limit in the OER process. This work is expected to contribute to the understanding of the modification mechanism of Fe‐doped cobalt‐based oxides and the exploitation of layer‐structured oxides for energy application.

TANK-binding kinase 1 (TBK1), a noncanonical member of the inhibitor-kappaB kinases (IKKs) family, plays a vital role in coordinating the signalling pathways of innate immunity, involving in the process of neuroinflammation, autophagy, and oncogenesis. In current study, based on rational drug design strategy, we discovered a series of 1H-pyrazolo[3,4-b]pyridine derivatives as potent TBK1 inhibitors and dissected the structure–activity relationships (SARs). Through the several rounds of optimisation, compound 15y stood out as a potent inhibitor on TBK1 with an IC50 value of 0.2 nM and also displayed good selectivity. The mRNA detection of TBK1 downstream genes showed that compound 15y effectively inhibited TBK1 downstream IFN signalling in stimulated THP-1 and RAW264.7 cells. Meanwhile, compound 15y exhibited a micromolar antiproliferation effect on A172, U87MG, A375, A2058, and Panc0504 cell lines. Together, current results provided a promising TBK1 inhibitor 15y as lead compound for immune- and cancer-related drug discovery.

Growth mechanisms of (0001) wurtzite GaN films at low temperature are investigated by molecular dynamics simulations and experiments. The crystallization properties of GaN films deteriorate dramatically at low temperature due to the limited energy available for atomic surface migration and incorporation into the perfect lattice sites. In our simulation, growth interruption stage is periodically introduced and the as-deposited GaN films are treated with energy-carrying argon ions at this stage. The surface atoms located at the weak binding sites can acquire energy from the argon ions for secondary migration and incorporation into the perfect lattice sites. As a result, the crystallization properties of GaN films are significantly improved. GaN films are experimentally grown on sputtered AlN/sapphire substrates at 600 °C via inductively coupled plasma metal organic chemical vapor deposition along with periodic argon plasma treatment. The as-deposited film acquires energy from the plasma, leading to significant improvement of the crystalline properties. The surface morphology of the GaN film demonstrates a noticeable smoothing effect, with an evident increase in grain size from submicron to micron level. Additionally, GaN film with the optimized surface morphology exhibits high c -axis and in-plane orientations, and the full width half maximums of (002) and (102) x-ray diffraction rocking curves are 0.25° and 0.32°, respectively. These results provide effective guidance for the growth of GaN films at low temperature.

Idiopathic pulmonary fibrosis (IPF) is a chronic fatal lung disease with a median survival time of 3–5 years. Inaccurate diagnosis, limited clinical therapy and high mortality together indicate that the development of effective therapeutics for IPF is an urgent need. In recent years, it was reported that DDRs are potential targets in anti-fibrosis treatment. Based on previous work we carried out further structure modifications and led to a more selective inhibitor 47 by averting some fibrosis-unrelated kinases, such as RET, AXL and ALK. Extensive profiling of compound 47 has demonstrated that it has potent DDR1/2 inhibitory activities, low toxicity, good pharmacokinetic properties and reliable in vivo anti-fibrosis efficacy. Therefore, we confirmed that discoidin domain receptors are promising drug targets for IPF, and compound 47 would be a promising candidate for further drug development.

Shallow coastal waters (SCWs) have attracted wide attention in recent years due to their strong carbon sequestration capacity. However, the complex carbon dioxide (CO2) dynamics in the water column makes it difficult to estimate the air–water CO2 fluxes (FCO2) accurately. We developed a numerical model of CO2 dynamics in water based on field measurements for a typical stratified semi-enclosed shallow bay: the Yatsushiro Sea, Japan. The developed model showed an excellent ability to reproduce the stratification and CO2 dynamics of the Yatsushiro Sea. Through numerical model simulations, we analyzed the annual CO2 dynamics in the Yatsushiro Sea in 2018. The results show that the effect of stratification on the CO2 dynamics in seawater varies greatly depending on the distance from the estuary and the period. In the estuarine region, stratification manifests itself throughout the year by promoting the maintenance of a high partial pressure of CO2 (pCO2) in surface waters, resulting in surface pCO2 being higher than atmospheric pCO2 for up to 40 days during the flood period (average surface pCO2 of 539.94 µatm). In contrast, in areas farther from the estuary, stratification mainly acts to promote the maintenance of high pCO2 in surface waters during periods of high freshwater influence. Then changes to a lower surface pCO2 before the freshwater influence leads towards complete dissipation. Finally, we estimated the FCO2 of the Yatsushiro Sea in 2018, and the results showed that the Yatsushiro Sea was a sink area for atmospheric CO2 in 2018 (−1.70 mmol/m2/day).

Intense shock boundary-layer interaction may lead to multiple unstart modes existing in a hypersonic inlet. Thus, self-start problems become complex and cannot be explained using the classical double-solution theory of air inlet. The essence of the self-start process of a hypersonic inlet is the vanishment of separations near or in the inlet. To clarify self-start characteristics, experiments were conducted on three distinct types of unstart mode: the flow mode of small separation on body (SSB), large separation on body (LSB), and dual separations on both body and lip (DSBL); researchers recently discovered these as the unstart modes of hypersonic inlet. The results from the current experiment are as follows: (1) The SSB vanishes by raising the angle of attack (alpha). Before the vanishing point is reached, there is a dwindling process for this separation. (2) The LSB vanishes through acceleration or a decreasing alpha. (3) DSBL are difficult to vanish directly, which results in poor self-start performance. However, the DSBL flow mode may convert to LSB unstart form—which is easier to self-start—by decreasing the alpha. The Flow Field Reconstruction Method was designed to improve the self-start of the DSBL flow mode, and it was validated through experiments. Analysis of the flow mechanism revealed the reason for the poor self-start performance of the DSBL unstart mode: large-scale separation on the lip side cannot be promoted to vanish through broadwise spillage due to the resistance of sideboards. The results of this study could greatly enrich the existing theory of start problems for hypersonic inlets.

Precisely segmenting the hippocampus from the brain is crucial for diagnosing neurodegenerative illnesses such as Alzheimer’s disease, depression, etc. In this research, we propose an enhanced hippocampus segmentation algorithm based on 3D U-Net that can significantly increase hippocampus segmentation performance. First, a dynamic convolution block is designed to extract information more comprehensively in the steps of the 3D U-Net’s encoder and decoder. In addition, an improved coordinate attention algorithm is applied in the skip connections step of the 3D U-Net to increase the weight of the hippocampus and reduce the redundancy of other unimportant location information. The algorithm proposed in this work uses soft pooling methods instead of max pooling to reduce information loss during downsampling steps. The datasets employed in this research were obtained from the MICCAI 2013 SATA Challenge (MICCAI) and the Harmonized Protocol initiative of the Alzheimer’s Disease Neuroimaging Initiative (HarP). The experimental results on the two datasets prove that the algorithm proposed in this work outperforms other commonly used segmentation algorithms. On the HarP, the dice increase by 3.52%, the mIoU increases by 2.65%, and the F1 score increases by 3.38% in contrast to the baseline. On the MICCAI, the dice, the mIoU, and the F1 score increase by 1.13%, 0.85%, and 1.08%, respectively. Overall, the proposed model outperforms other common algorithms.

Abstract With the combination of Mobile Edge Computing (MEC) and the next generation cellular networks, computation requests from end devices can be offloaded promptly and accurately by edge servers equipped on Base Stations (BSs). However, due to the densified heterogeneous deployment of BSs, the end device may be covered by more than one BS, which brings new challenges for offloading decision, that is whether and where to offload computing tasks for low latency and energy cost. This paper formulates a multi-user-to-multi-servers (MUMS) edge computing problem in ultra-dense cellular networks. The MUMS problem is divided and conquered by two phases, which are server selection and offloading decision. For the server selection phases, mobile users are grouped to one BS considering both physical distance and workload. After the grouping, the original problem is divided into parallel multi-user-to-one-server offloading decision subproblems. To get fast and near-optimal solutions for these subproblems, a distributed offloading strategy based on a binary-coded genetic algorithm is designed to get an adaptive offloading decision. Convergence analysis of the genetic algorithm is given and extensive simulations show that the proposed strategy significantly reduces the average latency and energy consumption of mobile devices. Compared with the state-of-the-art offloading researches, our strategy reduces the average delay by 56% and total energy consumption by 14% in the ultra-dense cellular networks.

ObjectiveBrain atrophy is an important imaging characteristic of cerebral small vascular disease (CSVD). Our study explores the linear measurement application on CT images of CSVD patients and develops a fully automatic brain atrophy classification model. The second aim was to compare it with the end-to-end Convolutional Neural Networks (CNNs) model.MethodsA total of 385 subjects such as 107 no-atrophy brain, 185 mild atrophy, and 93 severe atrophy were collected and randomly separated into training set (n = 308) and test set (n = 77). Key slices for linear measurement were manually identified and used to annotate nine linear measurements and a binary classification of cerebral sulci widening. A linear-measurement-based pipeline (2D model) was constructed for two-types (existence/non-existence brain atrophy) or three-types classification (no/mild atrophy/severe atrophy). For comparison, an end-to-end CNN model (3D-deep learning model) for brain atrophy classification was also developed. Furthermore, age and gender were integrated to the 2D and 3D models. The sensitivity, specificity, accuracy, average F1 score, receiver operating characteristics (ROC) curves for two-type classification and weighed kappa for three-type classification of the two models were compared.ResultsAutomated measurement of linear measurements and cerebral sulci widening achieved moderate to almost perfect agreement with manual annotation. In two-type atrophy classification, area under the curves (AUCs) of the 2D model and 3D model were 0.953 and 0.941 with no significant difference (p = 0.250). The Weighted kappa of the 2D model and 3D model were 0.727 and 0.607 according to standard classification they displayed, mild atrophy and severe atrophy, respectively. Applying patient age and gender information improved classification performances of both 2D and 3D models in two-type and three-type classification of brain atrophy.ConclusionWe provide a model composed of different modules that can classify CSVD-related brain atrophy on CT images automatically, using linear measurement. It has similar performance and better interpretability than the end-to-end CNNs model and may prove advantageous in the clinical setting.

Ethnopharmacological relevance: Several studies have confirmed that intestinal microflora dysbiosis correlates with the severity of COVID-19 patients. Clinical meta-analysis and our data show that the circulating miRNAs like miRNA-146 and the levels of serum cytokines in the peripheral blood are closely related to mild to moderate COVID-19 patients. Despite the widespread use of traditional herbal medicine for COVID-19 in China, the mechanisms remain largely uncovered. Aim of the study: We conducted an observational case-control study to verify the efficacy and safety of traditional Chinese herbal medicine Qushi Jianpi Hewei Decoction (QJHD) for mild to moderate COVID-19 patients, and investigated the potential biomolecular mechanisms through metagenomics and transcriptomic sequencing methods. Materials and methods: QJHD was given orally twice a day individually for 14 to 28 days. A total of 10 patients were enrolled in the study and given QJHD. We observed advantages in clinical cure time rate, and the relief of gastrointestinal symptoms as compared with reports in the literature. The metagenomics sequencing data of fecal microflora and transcriptomic sequencing data of blood cell in patients with SARS-Cov-2 infection patients were selected compared to the healthy control donors. Results: No serious adverse events were reported. Meanwhile, the transcriptome analysis showed a decrease of the hsa-miR-21-5p expression in peripheral blood without QJHD. The species composition analysis showed an increase in the expression of Faecalibacterium prausnitzii in the intestinal tract; The interleukin-10 (IL-10) expression also in COVID-19 patient decreased in peripheral blood compared with healthy control donors. And we found an improvement in these parameters in patients taking QJHD. Conclusions: Our findings show that QJHD could improve clinical outcomes of mild to moderate COVID-19 patients, probably through beneficial immunomodulatory effects by regulating Faecalibacterium prausnitzii in the intestinal tract and hsa-miR-21 and IL-10 expression in peripheral blood. (chictr.org.cn, ChiCTR2000030305)

A high-Q mid-infrared Tamm plasmon (TP) absorber using MgF2 and Ge aperiodic tandem films is designed by the genetic algorithm and fabricated by electron beam evaporation and magnetron sputtering. Such a design circumvents the need for the distributed Bragg reflector grating, and the thickness of individual MgF2 films is much smaller than a quarter of wavelength in films (λ/4n). The fabricated TP absorber exhibits a high and sharp absorption peak at 2.73 μm with a quality factor (Q) of 144, while the simulated counterpart has the absorption peak at 2.72 μm with a Q of 155. The profiles of an electromagnetic field in the tandem films are also simulated to reveal the mechanism of narrow thermal emission. Such a high-Q TP absorber is very promising in the mid-infrared simulator and detection.

Experiments were conducted in this study to reveal the flow characteristics of a variable cross-section S-shaped isolator, when applying the steady-state back pressure at the isolator outlet. The self-excited oscillation characteristics of the shock train generated under the influence of steady-state back pressure at an incoming flow speed of Mach 2, were also studied. The findings suggest that pressure oscillation within the area affected by the shock train’s flow field was significantly more potent than outside the affected area. Moreover, the forward movement velocity of the shock train in the variable cross-section S-shaped isolator was not uniform. The forward movement speed was slower when encountering sharp turns and faster during gentle turns. In the shock train flow field, high-frequency pressure oscillations, which mainly stemmed from the oscillations of the separated shock legs, propagated more readily within the flow field than low-frequency pressure oscillations. The significant separation of the shock train flow field will switch between the top and bottom walls, and the frequency of pressure oscillation in the large separation region is low. On another note, the closer the distance between two points is in the shock flow field, the stronger the coherence of pressure oscillations will be. In the distance upstream of the shock train flow field, the turbulent boundary layer (TBL) determines pressure oscillations instead of the shock train flow field, so the coherence was very high.

Objective To perform a prospective study to determine the risk factors associated with perirenal haematoma development after percutaneous renal biopsy (PRB). Methods This multivariate prospective study collected demographic and clinical data from all consecutive adult patients that underwent real-time ultrasound-guided PRB of native kidneys. All biopsies were performed by two well-trained ultrasound physicians using 16G biopsy needles. Routine renal ultrasounds were performed within 12–24 h after biopsies in order to observe post-biopsy perirenal haematoma formation. Patients were stratified based on the occurrence of post-biopsy haematoma development. Results This prospective study enrolled 218 patients and stratified them into a haematoma group ( n = 126) and a non-haematoma group ( n = 92). Binary logistic regression analysis identified female patients (odds ratio [OR] 1.990; 95% confidence interval [CI] 1.125, 3.521), patients with a body mass index (BMI) ≥28 kg/m 2 (OR 2.660; 95% CI 1.097, 6.449) and patients with immediate post-biopsy active bleeding (IPAB) (OR 2.572; 95% CI 1.422, 4.655) as being more likely to have perirenal haematoma after real-time ultrasound guided PRB of native kidneys. Conclusion Female sex, a BMI ≥28 kg/m 2 and IPAB were risk factors for perirenal haematoma after real-time ultrasound-guided PRB of native kidneys.

If the measurand changes during the spectrum acquisition process, it easily leads to the failure of the classic demodulation algorithms of low-finesse optical fiber Fabry-Perot (FP) sensors. To address this problem, a novel demodulation model is proposed based on the definition of the instantaneous frequency. The proposed model establishes the relationship between the optical path length (OPL) of the FP cavity and the instantaneous frequency distribution of the FP interference spectrum. The link between the classic FFT algorithm and this model is discussed, and it is found that this model can be viewed as a generalized form of the FFT algorithm. Based on this model, the Doppler-induced demodulation error is analyzed. The analysis uncovers that the average frequency of the FP interference spectrum should be used for the evaluation of the error, and the error is proportional to the variation of OPL during the spectrum acquisition period. Further, numerical simulation and an experiment were carried out to verify the proposed model, and results show that the proposed model is effective for the dynamic low-finesse FP cavity. It is the first time that the idea of instantaneous frequency is introduced for the FP demodulation, and this model provides us a new way to cope with the FP sensing signal.

Genomic alterations are commonly found in the signaling pathways of fibroblast growth factor receptors (FGFRs). Although there is no selective FGFR inhibitors in market, several promising inhibitors have been investigated in clinical trials, and showed encouraging efficacies in patients. By designing a hybrid between the FGFR-selectivity-enhancing motif dimethoxybenzene group and our previously identified novel scaffold, we discovered a new series of potent FGFR inhibitors, with the best one showing sub-nanomolar enzymatic activity. After several round of optimization and with the solved crystal structure, detailed structureactivity relationship was elaborated. Together with in vitro metabolic stability tests and in vivo pharmacokinetic profiling, a representative compound (35) was selected and tested in xenograft mouse model, and the result demonstrated that inhibitor 35 was effective against tumors with FGFR genetic alterations, exhibiting potential for further development. KEY WORDS: Fibroblast growth factor, Tyrosine kinase receptor, Structure-based, Crystallography, Selectivity, Hybrid, 5-Hydrosulfonyl-5H-pyrrolo[2,3-b]pyrazine, Inhibitor

In order to detect the aerodynamic instability of a multistage axial compressor more accurately and earlier, the harmonic Fourier mean amplitude analysis method and heterotopic variance analysis method are developed. The dynamic instability prediction performance of the two methods is studied on a low-speed and a high-speed two-stage axial compressor. The harmonic Fourier mean amplitude analysis method is suitable for predicting the aerodynamic instability of a multistage axial compressor in the form of a rotating stall. Compared with the traditional harmonic Fourier analysis methods, the harmonic Fourier mean amplitude analysis method can capture the detail of the pressure signal more accurately and it can effectively prevent instability misjudgment. The heterotopic variance analysis method is developed based on the conventional variance analysis method, and it can be used to distinguish whether the compressor is in the rotating stall or the surge state. The heterotopic variance analysis method can predict the aerodynamic instability ahead of the harmonic Fourier mean amplitude analysis method, and fewer circumferential measuring points were employed. The layout of the measuring points also influences the detection of the aerodynamic instability of the compressor. The aerodynamic instability of the high-speed axial compressor can be predicted earlier by employing measuring points at the compressor outlet.

As a novel network paradigm, Software Defined Networking (SDN) decouples control logic functions from data forwarding devices, and introduces a separate control plane to manipulate underlying switches via southbound interfaces like OpenFlow. This paradigm offers numerous benefits for wide area networks (WAN), like promoting application performance and reducing deployment costs, but poses serious challenges on the storage resources and lookup performance of large-scale flow tables in OpenFlow switches. This paper is thus motivated to propose an efficient differentiated storage architecture for large-scale flow tables in OpenFlow-based software-defined WAN. Firstly, we investigate into the impact of wildcards in match fields on the packet-in-batch feature within a flow based on network traffic locality. Then, packet flows are dynamically distinguished into active ones and idle ones in terms of their short-term states. Subsequently, we store the match fields of active flows and idle flows respectively in TCAM and SRAM, and the content fields of both types of flows in DRAM, to effectively relieve the insufficiency of TCAM capacity. Finally, we evaluate the performance of our proposed flow table storage architecture with real network traffic traces by experiments. The experimental results indicate that our proposed storage architecture with the active/idle flow differentiation obviously outperforms the traditional one applying the elephant/mice flow differentiation in terms of TCAM hit rates and average flow table access time.

The complex device structure and costly preparation process have hindered the development and application of the GaN-based ultraviolet and infrared (UV–IR) dual-color photodetector. In this work, we designed and prepared an Au/GaN-nanopillar-based hot-electron photodetector that can operate in the short-wave infrared range, well below the GaN bandgap energy. A suitable Schottky barrier height was developed for a higher photo-to-dark current ratio by post-etching annealing. The surface plasmons generated by Au/GaN-nanopillar arrays could effectively improve the light absorption efficiency. As a result, compared with the planar device, the responsivity of the Au/GaN-nanopillar device could be enhanced by about two orders of magnitude. With the advantages of a simple structure and easy preparation, the proposed devices are promising candidates for application in UV–IR dual-color photodetection.

Abstract Background Human immunodeficiency virus (HIV) infection has been recognized as a risk factor for both ischemic and hemorrhagic stroke among young adults. However, information on the optimal management of HIV patients presenting with presumed acute ischemic stroke within the time window of intravenous recombinant tissue plasminogen activator (IV-rtPA) thrombolysis is limited. To the best of our knowledge, the use of multimodal computed tomography (CT)-based imaging to guide acute-phase treatment for patients with HIV infection has never been reported. Case presentation We report the clinical, imaging, and immunological features of a young man suffering from presumed acute ischemic stroke, initially without awareness of the presence of HIV infection. IV-rtPA guided by multimodal CT, including brain CT angiography (CTA) and CT perfusion (CTP), was administered at the emergency department. His symptoms were relieved, and there was no recurrence during the 2-month follow up. Conclusions Mutimodal CT is a valuable and promising tool for the early management of HIV-infected patients, especially for those presenting within the strict thrombolysis time window.

Orbital-angular-momentum (OAM) beams have great potential for multiplexing signals in optical communication, but creating a compact source is challenging. The authors integrate a chip-scale optical vortex emitter and DFB laser into a single monolithic device for direct electrically pumped production of OAM beams.

Electroacupuncture (EA) has become popular for its adjustable strength and frequency and easy quantification in the clinic and has demonstrated therapeutic potential for Alzheimer’s disease (AD). However, the mechanism remains unknown. Abnormally activated c-Jun N-terminal kinase (JNK) has been closely related to the pathological process of AD. The aim of this study was to investigate the effect of EA on cognitive impairment and the role of the JNK signaling pathway in AD model amyloid precursor protein (APP)/presenilin 1 (PS1) mice. The memory and learning ability of each group was assessed using the Morris Water Maze (MWM). Immunofluorescence, immunohistochemistry and Western blot were performed to measure the expression of APP, JNK, phosphorylated (P-)JNK, mitogen-activated protein kinase 4 (MKK4), MKK7, c-Jun and caspase-3 in hippocampal tissue samples in APP/PS1 mice after EA intervention. Obvious cognitive deficits were observed in the AD model APP/PS1 mice in the MWM test and were associated with JNK signaling pathway activation and APP upregulation. Four weeks of EA significantly ameliorated the cognitive impairments and inhibited JNK signaling pathway activation and APP upregulation. Taken together, the findings demonstrated that EA can reverse cognitive deficits and substantially lower the burden of APP in AD model APP/PS1 mice, at least partially through inhibiting the JNK signaling pathway and regulating apoptosis signals. Therefore, EA may offer an effective alternative therapeutic approach for AD.

In the hypersonic regime, noncircular missiles have attracted significant attention from researchers. The paper first summarizes the development and present situation of the noncircular missiles at home and abroad. Previous research found that the cross-section shape of missiles has a direct influence on the aerodynamics performance. To find the best cross-section shape in terms of lift-drag-ratio, an efficient and robust shape optimization framework is developed. Class/shape function transformation (CST) method and power-law curve are introduced to complete the parametric modeling of the noncircular missile. The evolutionary algorithm has been utilized to improve the optimization efficiency. A combination of script and journal files is written to automate the CAD loft, mesh generation, and CFD simulations process. Finally, the forebody section of a missile body is chosen as an example to deliver the whole optimization steps. The optimization results show that the lift-to-drag ratio increases from 1.8 to 2.4 when the hypersonic missile forebody cruises at the design condition. The results also demonstrate that the optimized configuration has a better aerodynamic performance than the original one over a wide speed range from Mach 2 to 8 and a wide attack of angle range from 0 to 30.

A theoretical analysis is presented to investigate the orbital angular momentum (OAM) mode purity of microring-resonator-based integrated optical vortex emitters. By extending the dipole model for integrated vortex emitters, the influence of optical losses and grating imperfections on OAM mode purity of the output beam is investigated, thus clarifying the mode purity performance of the device in many practical scenarios. This work provides an efficient tool for the design of emitters with high OAM mode purity for optical communications or quantum information processing.

WD40 is a ubiquitous domain presented in at least 361 human proteins and acts as scaffold to form protein complexes. Among them, WDR5 protein is an important mediator in several protein complexes to exert its functions in histone modification and chromatin remodeling. Therefore, it was considered as a promising epigenetic target involving in anti-cancer drug development. In view of the protein–protein interaction nature of WDR5, we initialized a campaign to discover new peptide-mimic inhibitors of WDR5. In current study, we utilized the phage display technique and screened with a disulfide-based cyclic peptide phage library. Five rounds of biopanning were performed and isolated clones were sequenced. By analyzing the sequences, total five peptides were synthesized for binding assay. The four peptides are shown to have the moderate binding affinity. Finally, the detailed binding interactions were revealed by solving a WDR5-peptide cocrystal structure.

An inductively coupled plasma metal organic chemical vapor deposition (ICP-MOCVD) based on showerhead structure is proposed for the low temperature growth of thin solid films including GaN. The flow field of precursors in the chamber of ICP-MOCVD was analyzed and the structure of showerhead was optimized by changing the showerhead diameter to obtain uniform velocity field above the substrate. The thickness non-uniformity of GaN films grown at 600 °C was improved from 5.14% to 1.86% after the optimization of showerhead. On that basis, the influence of triethylgallium (TEG) and trimethylgallium (TMG) on low-temperature GaN growth were investigated and TEG was proved to be the more appropriate Ga source in this case. Finally, GaN film with high c -axis and in-plane orientations was obtained on sputtered AlN/sapphire template and the full width half maximums of (002) and (102) x-ray rocking curves are 0.45° and 0.57° respectively. Our results provide a practicable method for the optimization of low-temperature MOCVD, which has potential to obtain large-scale crystalline films at low temperature.

Low-cost and high-speed single-mode semiconductor lasers are increasingly required as wide-band access fiber communication expands in recent years. Here, a high-speed laterally coupled distributed feedback (LC-DFB) laser array is achieved based on a SiO2 planarization process. The device exhibits low threshold currents of about 12 mA and high slope efficiencies over 0.26 W/A. Stable single mode operation and high-speed performance are realized with side mode suppression ratios (SMSR) over 45 dB, and 3-dBe bandwidths exceed 14 GHz for all four channels. Such a high-speed and process simple LC-DFB laser array shows great potential to the low-cost fiber communication networks.