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Pseudorabies virus (PRV) is the causative agent of Aujeszky's disease in pigs. The low-density lipoprotein receptor (LDLR) is a transcriptional target of the sterol-regulatory element-binding proteins (SREBPs) and participates in the uptake of LDL-derived cholesterol. However, the involvement of LDLR in PRV infection has not been well characterized. We observed an increased expression level of LDLR mRNA in PRV-infected 3D4/21, PK-15, HeLa, RAW264.7, and L929 cells. The LDLR protein level was also upregulated by PRV infection in PK-15 cells and in murine lung and brain. The treatment of cells with the SREBP inhibitor, fatostatin, or with SREBP2-specific small interfering RNA prevented the PRV-induced upregulation of LDLR expression as well as viral protein expression and progeny virus production. This suggested that PRV activated SREBPs to induce LDLR expression. Furthermore, interference in LDLR expression affected PRV proliferation, while LDLR overexpression promoted it. This indicated that LDLR was involved in PRV infection. The study also demonstrated that LDLR participated in PRV invasions. The overexpression of LDLR or inhibition of proprotein convertase subtilisin/kexin type 9 (PCSK9), which binds to LDLR and targets it for lysosomal degradation, significantly enhanced PRV attachment and entry. Mechanistically, LDLR interacted with PRV on the plasma membrane, and pretreatment of cells with LDLR antibodies was able to neutralize viral entry. An in vivo study indicated that the treatment of mice with the PCSK9 inhibitor SBC-115076 promoted PRV proliferation. The data from the study indicate that PRV hijacks LDLR for viral entry through the activation of SREBPs.IMPORTANCEPseudorabies virus (PRV) is a herpesvirus that primarily manifests as fever, pruritus, and encephalomyelitis in various domestic and wild animals. Owing to its lifelong latent infection characteristics, PRV outbreaks have led to significant financial setbacks in the global pig industry. There is evidence that PRV variant strains can infect humans, thereby crossing the species barrier. Therefore, gaining deeper insights into PRV pathogenesis and developing updated strategies to contain its spread are critical. This study posits that the low-density lipoprotein receptor (LDLR) could be a co-receptor for PRV infection. Hence, strategies targeting LDLR may provide a promising avenue for the development of effective PRV vaccines and therapeutic interventions.
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Herpesvirus Suídeo 1 , Lipoproteínas LDL , Pseudorraiva , Doenças dos Suínos , Animais , Humanos , Camundongos , Herpesvirus Suídeo 1/fisiologia , Lipoproteínas LDL/metabolismo , Pró-Proteína Convertase 9 , Pseudorraiva/virologia , Suínos , Doenças dos Suínos/virologia , Internalização do Vírus , Linhagem CelularRESUMO
BACKGROUND: Lung cancer is a prevalent and severe form of malignant tumors worldwide. tRF-Leu-CAG, a recently discovered non-coding single-stranded small RNA derived from transfer RNA, has sparked interest in exploring its biological functions and potential molecular mechanisms in lung cancer. METHODS: The abundance of tRF-Leu-CAG was measured via quantitative real-time polymerase chain reaction (qRT-PCR) in 96 sets of lung cancer tissue samples obtained from clinical patients. Subsequently, both in vivo and in vitro experiments were conducted to validate the biological functions of tRF-Leu-CAG in lung cancer. Furthermore, an exploration of the potential target genes of tRF-Leu-CAG and its association with autophagy and drug resistance in lung cancer was undertaken. RESULTS: Our analysis revealed a significant upregulation of tRF-Leu-CAG in non-small cell lung cancer (NSCLC) tissues. Additionally, we observed that heightened expression of tRF-Leu-CAG significantly augmented the proliferation and migration of NSCLC cells, facilitated cell cycle progression, and suppressed apoptosis. Furthermore, we identified transcription elongation factor A3 (TCEA3) as a direct target gene of tRF-Leu-CAG. TCEA3 inhibited the proliferation and migration of NSCLC, and tRF-Leu-CAG promoted the proliferation and migration of NSCLC by mediating the silencing of TCEA3. Moreover, we demonstrated that the augmentation of paclitaxel resistance by tRF-Leu-CAG was contingent on autophagy. Finally, tRF-Leu-CAG notably accelerated tumor growth and promoted the process of epithelial-mesenchymal transition (EMT) in vivo. CONCLUSIONS: tRF-Leu-CAG promotes NSCLC tumor growth and metastasis by targeting TCEA3 and promotes paclitaxel resistance by enhancing cellular autophagy. These results provide potentially effective targets and therapeutic options for the clinical treatment of NSCLC.
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Apoptose , Autofagia , Carcinoma Pulmonar de Células não Pequenas , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares , Humanos , Autofagia/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Animais , Camundongos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Apoptose/genética , Movimento Celular/genética , Carcinogênese/genética , Resistencia a Medicamentos Antineoplásicos/genética , RNA de Transferência/genética , RNA de Transferência/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
We present a spectral-scanning frequency-modulated continuous wave (FMCW) 3D imaging system capable of producing high-resolution depth maps with an extended field of view (FOV). By employing a multipass configuration with an echelle grating, the system achieves an FOV of 5.5° along the grating axis. The resulting depth maps have a resolution of 70 × 40 pixels, with a depth resolution of 5.1â mm. The system employs an echelle grating for beam steering and leverages the multipass configuration for angular FOV magnification. Quantitative depth measurements and 3D imaging results of a static 3D-printed depth variation target are demonstrated. The proposed approach offers a promising solution for enhancing the FOV of spectral-scanning FMCW LiDAR systems within a limited wavelength-swept range, thereby reducing system complexity and cost, paving the way for improved 3D imaging applications.
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OBJECTIVE: This study aimed to assess the effectiveness of exercise therapy for patients with axial spondyloarthritis (axSpA). DATA SOURCES: We searched MEDLINE (via PubMed), Cochrane Library, Embase, Web of Science, Scopus, and SPORTDiscus for all relevant publications from database inception to March 2024, without language restriction. STUDY SELECTION: We included randomized controlled trials (RCTs) of patients with axSpA in which ≥1 group received exercise therapy. DATA EXTRACTION: Two independent reviewers assessed the quality of the literature using the Cochrane Collaboration Risk of Bias Tool 2.0. The outcomes were ankylosing spondylitis (AS) disease activity score (ASDAS), Bath AS disease activity index (BASDAI), Bath AS functional index (BASFI), Bath AS metrology index (BASMI), 6-minute walk test (6MWT), chest expansion capacity, peak oxygen consumption (VO2peak), pain, fatigue, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR). DATA SYNTHESIS: A total of 20 RCTs, including 1670 patients, were included in this study. Compared with the control group, exercise therapy improved BASFI (weighted mean difference [WMD], -0.49; 95% confidence interval [CI], -0.65 to -0.32; I2=3.4%; P=.414), BASMI (WMD, -0.49; 95% CI, -0.87 to -0.11; I2=71.9%; P=.679), BASDAI (WMD, -0.78; 95% CI, -1.08 to -0.47; I2=55.9%; P=.021), ASDAS (WMD, -0.44; 95% CI, -0.64 to -0.24; I2=0.0%; P=.424), VO2peak (WMD, 3.16; 95% CI, 1.37-4.94; I2=0.0%; P=.873), 6MWT (WMD, 27.64; 95% CI, 12.04-43.24; I2=0.0%, P=.922), pain (standardized mean difference [SMD], -0.47; 95% CI, -0.74 to -0.21; I2=66.0%, P=.046), and fatigue (SMD, -0.49; 95% CI, -0.71 to -0.27; I2=0.0%; P=.446). However, no significant benefit was found in chest expansion, CRP, and ESR outcomes. CONCLUSIONS: Exercise therapy is an effective strategy for improving disease control and symptom relief in patients with axSpA.
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Porcine circovirus 4 (PCV4) is a newly identified virus belonging to PCV of the Circoviridae family, the Circovirus genus. We previously found that PCV4 is pathogenic in vitro, while the virus's replication in cells is still unknown. In this study, we evaluated the N-terminal of the PCV4 capsid (Cap) and identified an NLS at amino acid residues 4-37 of the N-terminus of the PCV4 Cap, 4RSRYSRRRRNRRNQRRRGLWPRASRRRYRWRRKN37. The NLS was further divided into two fragments (NLS-A and NLS-B) based on the predicted structure, including two α-helixes, which were located at 4RSRYSRRRRNRRNQRR19 and 24PRASRRRYRWRRK36, respectively. Further studies showed that the NLS, especially the first α-helixes formed by the NLS-A fragment, determined the nuclear localization of the Cap protein, and the amino acid 4RSRY7 in the NLS of the PCV4 Cap was the critical motif affecting the VLP packaging. These results will provide a theoretical basis for elucidating the infection mechanism of PCV4 and developing subunit vaccines based on VLPs.
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Circovirus , Sinais de Localização Nuclear , Animais , Suínos , Sinais de Localização Nuclear/metabolismo , Capsídeo/metabolismo , Proteínas do Capsídeo/química , Aminoácidos/metabolismoRESUMO
Coumarin 3-carboxylic acid (CCA)-loaded radio-fluorescent hydrogels have attracted interest for ionizing radiation dosimeters, but their sensitivity needs to be improved. In this study, we added ammonium persulfate (APS) to a polyacrylamide (PAAm)-CCA hydrogel. The introduction of APS improved the hydrogel dose sensitivity to 336.02 Gy- 1, which is 1.8 times that of the counterpart without APS. Our hydrogel can measure the X-ray dose in a range of 0 - 15 Gy with a lower limit of detection (LOD) of 0.1 Gy. Additionally, the hydrogel can sense X-ray doses within a wide range of the dose rate and temperature, and the doseâresponse can be well retained 7 days postirradiation. Therefore, we think this study provides a simple and robust method to improve the sensitivity of CCA hydrogel dosimeters, presenting great potential in clinical radiotherapy.
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Hidrogéis , Sais , Raios X , CorantesRESUMO
Optical wireless communication (OWC) using line-of-sight connections has great application potential for indoor scenes due to its advantages of high data transmission speed and privacy. In our proposed system, we use infrared tunable vertical-cavity surface-emitting laser (VCSEL) as light source, array waveguide gratings (AWG) combined with 6 × 6 integrated optical fiber arrays as a router to realize ultrafast beam-steering and high capacity point-to-point data transmission, which makes the indoor OWC system compact, low-cost, and easy to install. The high tuning rate of VCSEL enables the channel switching to be completed within 1.7 µs. Based on the modulation format of non-return-to-zero on-off keying (NRZ-OOK), a data rate of 12 Gbit/s per channel can be realized with high sensitivity through 3.1 m free space when the detected optical power is low. The system is proved to be a flexible link with high-speed communication for mobile terminals in a limited space.
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By using narrow infrared (IR) optical beams, optical wireless communication (OWC) system can realize ultra-high capacity and high-privacy data transmission. However, due to the point-to-point connection approach, a high accuracy localization system and beam-steering antenna (BSA) are required to steer the signal beam to user terminals. In this paper, we proposed an indoor beam-steering IR OWC system with high accuracy and calibration-free localization ability by employing a coaxial frequency modulated continuous wave (FMCW) light detection and ranging (LiDAR) system. In the meantime, benefitting from the mm-level ranging accuracy of the LiDAR system, a useful approach to assess the feasibility of the link alignment between beam-steering antenna and users is first demonstrated. With the assistance of the LiDAR system, we experimentally achieved the localization of user terminals with a 0.038-degree localization accuracy and on-off keying (OOK) downlink error-free transmission of 17 Gb/s in free space at a 3-m distance is demonstrated. The highest transmission data rate under the forward error correction (FEC) criterion (Bit error rate (BER) <3.8×103) can reach 24 Gb/s.
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The beam-steering device is a critical component in LiDAR systems for 3D imaging. Solid-state beam-steering devices attract the most attention for their advantages of robustness, fast beam-steering speed, and stability. However, solid-state beam-steering devices, such as optical phased arrays (OPAs), are challenging to realize 2D scanning ability. Here we employed a virtually imaged phased array (VIPA) in the LiDAR system to realize all solid-state two-dimensional (2D) beam-steering based on dispersion only. A frequency swept laser source is used for performing optical frequency-modulated continuous-wave (FMCW) ranging and 2D beam steering simultaneously. The 2D disperser is compact and can be easily implemented owing to its simple structure. The mechanism of continuous scanning and ranging is beneficial for obtaining high lateral resolution, and a lateral resolution of 0.06° is achieved. 3D maps of the object at a distance of 2 m are obtained with cm-level ranging precision. The frame rate of the proposed LiDAR system only depends on the wavelength-tuning speed of the swept laser source, with the potential to realize ultrafast solid-state LiDAR systems.
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Infrared optical wireless communication system can achieve ultrahigh capacity and high privacy data transmission. However, for using narrow infrared laser beam as carrier to transmit signal, the high-speed data transmission can only be achieved by point-to-point connection. With the rapid number increasement of consumer electronic devices, such connection method puts a heavy burden on the number of transmitters. Thus, the transmitting end with the point-to-multipoint capability or multi-user accessibility is required. In this paper, we present a multi-user accessible indoor infrared optical wireless communication system employing passive diffractive optics based on a virtually imaged phased array (VIPA). Multiple beams can be generated in a point-to-multipoint scheme by using VIPA-based beam-steering antenna (BSA). On the other hand, by tuning wavelength of laser source, fast 2D steering of multiple beams with the same steering trajectory is supported, which can be used for user ends with changing locations. In the experiment, 5 beams are generated by utilizing only one transmitter. All five beams can realize 12.5 Gb/s on-off-keying (OOK) data rate transmission. Free-space optical wireless transmission at 3.6-m communication distance is demonstrated for system performance verification and evaluation. a total 3.44°×7.9° scanning field of view of five beams is achieved.
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OBJECTIVES: This study was designed to observe the efficacy and safety of renal denervation from the inside and outside of renal arteries. METHODS: Fourteen beagles were randomly divided into a control group (n = 4) and treatment group (n = 10). One renal artery in every beagle of the treatment group was randomly assigned to an intimal group (10 renal arteries) which underwent percutaneous renal denervation from the inside, and another renal artery was assigned to an adventitial group (10 renal arteries) which underwent renal denervation from the outside by laparotomy. RESULTS: Compared with the intimal group, the renal norepinephrine (NE) concentration in the adventitial group had significantly decreased (p = 0.003) at 3 months postsurgery. Renal artery HE staining showed that the perineurium from the adventitial group appeared thickened. Western blotting showed that renal tissue tyrosine hydroxylase (TH) protein expression in the adventitial group was significantly lower than that in the intimal group (p < 0.01) at 3 months postsurgery. There was a renal artery stenosis and a renal atrophy in the intimal group after 1 month of follow-up. CONCLUSION: The inhibitory effect on renal sympathetic nerve activity was more effective in the adventitial group than the intimal group, and renal denervation in the former group was safe.
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Túnica Adventícia/patologia , Denervação/métodos , Hipertensão/terapia , Norepinefrina/sangue , Artéria Renal/cirurgia , Sistema Nervoso Simpático/fisiologia , Túnica Íntima/patologia , Animais , Denervação/efeitos adversos , Modelos Animais de Doenças , Cães , Rim/irrigação sanguíneaRESUMO
We synthesized a fluorescence ratiometric probe by combining coumarin and rhodamine B with ethylenediamine to sense Fe3+ and measure ionizing radiation doses. The presence of Fe3+ caused rhodamine to transition from a closed helical structure to an open-ring structure. Additionally, fluorescence resonance energy transfer (FRET) occurred between coumarin and rhodamine B. As a result, the fluorescence intensity at 405 nm (I405) due to coumarin was decreased, whereas that at 585 nm (I585) derived from open-ring structure rhodamine B was increased. The ratio of I585 and I405 (I585/I405) linearly increased as the Fe3+ concentration increased. The probe sensed Fe3+ in a 0-110 µM range, with a lower limit of detection (LOD) of 0.226 µM. Inspired by Fricke dosimeters, we extended the probe to measure X-ray doses using the fluorescence methodology. The probe measured X-ray doses in a 0-30 Gy range with a lower LOD of 0.5 Gy. Additionally, the dosing capability was independent of the dosing rates. Our probe showed potential for detecting Fe3+ and measuring ionizing radiation doses.
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Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes , Rodaminas/química , Corantes Fluorescentes/química , Transferência Ressonante de Energia de Fluorescência/métodos , Cumarínicos/química , Doses de RadiaçãoRESUMO
Porcine circoviruses (PCVs) contain four types: PCV1, PCV2, PCV3, and PCV4, all of which can infect pigs. Among them, PCV1 is non-pathogenic, and PCV2 can cause porcine circovirus diseases (PCVD) or porcine circovirus-associated diseases (PCVAD). Although the pathogenicity of PCV3 and PCV4 is still controversial, increasing evidence shows that PCV3 and PCV4 can cause PCV-related disease. However, mixed infection of PCV2, PCV3, and PCV4 with other pathogens often occurs in large-scale pig breeding, bringing severe economic losses to the global pig industry. In this study, the soluble recombinant proteins of PCV2, PCV3, and PCV4 Cap were expressed by the prokaryotic expression system and biotinylated to combine with the Streptavidin magnetic beads, followed by immunogenicity evaluation of the recombinant proteins. Furthermore, we also assessed the efficacy and immunogenicity of trivalent recombinant proteins conjugated with different adjuvants in mice. The results showed that the highly effective anti-PCV serum was successfully prepared, and the recombinant proteins conjugated with different adjuvants produced various degrees of humoral and cellular immunity in mice. Three recombinant proteins are effective immunogens, and the trivalent proteins coupled with the aluminum adjuvant or GM-CSF-CpG for two-dose immunization can stimulate prominent humoral and cellular immunity against PCVs in vivo. The soluble recombinant proteins are the most promising candidate for developing a trivalent vaccine against PCVs (PCV2, PCV3, and PCV4) infection simultaneously.
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Proteínas do Capsídeo , Infecções por Circoviridae , Circovirus , Circovirus/imunologia , Circovirus/genética , Animais , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Infecções por Circoviridae/veterinária , Infecções por Circoviridae/prevenção & controle , Infecções por Circoviridae/virologia , Infecções por Circoviridae/imunologia , Suínos , Camundongos , Doenças dos Suínos/virologia , Doenças dos Suínos/prevenção & controle , Doenças dos Suínos/imunologia , Proteínas Recombinantes/imunologia , Feminino , Vacinas Virais/imunologia , Camundongos Endogâmicos BALB C , Anticorpos Antivirais/sangueRESUMO
BACKGROUND: In the 21st century, 13% of patients undergoing open abdominal surgery, 25% of patients undergoing heart surgery, and 57% of patients admitted to the intensive care unit (ICU) are affected by acute kidney injury (AKI). METHODS: This prospective observational study included patients admitted directly to the ICU between June 2021 and December 2021. RESULTS: A total of 81 patients were enrolled after thoracic and abdominal (non-cardiac) surgery; 36 patients (44.4%) were diagnosed with AKI occurred within 7 days after surgery. Six-hour postoperative central venous pressure(CVP) was a risk factor for AKI in thoracic and abdominal (non-cardiac) postoperative patients (odds ratio [OR], 1.418; 95% confidence intervals [CI], 1.106-1.819; P = 0.006). Six-hour postoperative vein impedance index(VII) and CVP were significantly positively correlated (P = 0.031). The combination of 6-h postoperative VII with CVP (VII ≥0.34, CVP ≥7.5 mmHg) showed an area under the curve (AUC) of 0.787, In the subgroup analysis of patients with 6-h postoperative CVP <7.5 mmHg, there was a significant statistical difference in 6-h postoperative VII between the groups and those without AKI (P = 0.048). At 6-h postoperative CVP <7.5 mmHg, VII of ≥0.44 had a predictive value for AKI after thoracic and abdominal (non-cardiac) surgery, with an AUC of 0.669, a sensitivity of 41.2%, and a specificity of 94.4%. CONCLUSION: Six-hour postoperative CVP combined with VII can better predict the occurrence of AKI occurred within 7 days after thoracic and abdominal (non-cardiac) surgery but cannot predict the severity of AKI.
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Injúria Renal Aguda , Procedimentos Cirúrgicos Cardíacos , Humanos , Abdome/cirurgia , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/epidemiologia , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Pressão Venosa Central , Impedância Elétrica , Estudos ProspectivosRESUMO
Objective: The aim of this study is to examine the diagnostic significance of using handgrip dynamometry and diaphragmatic ultrasound in intensive care unit-acquired weakness (ICU-AW). Methods: This study included patients who received mechanical ventilation in the ICU at the Fourth Hospital of Hebei Medical University from July to December 2020. We collected comprehensive demographic data and selected conscious patients for muscle strength and ICU-AW assessments. The evaluation comprised grip strength measurement and bedside ultrasound for diaphragmatic excursion (DE) and thickening fraction (DTF). Results were documented for comparative analysis between patient groups, focusing on the diagnostic efficacy of grip strength, DE, DTF, and their combined application in diagnosing ICU-AW. Results: A total of 95 patients were initially considered for inclusion in this study. Following the exclusion of 20 patients, a final cohort of 75 patients were enrolled, comprising of 32 patients (42.6%) diagnosed with ICU-AW and 43 patients (57.4%) classified as non-ICU-AW. Comparative analysis revealed that grip strength, DE, and DTF were significantly lower in the ICU-AW group (P < 0.05). Subgroup analysis specific to male patients demonstrated a noteworthy decrease in grip strength, DE, and DTF within the ICU-AW group (P < 0.05). Receiver operating characteristic curve analysis indicated statistically significant diagnostic value for ICU-AW with grip strength, DE, DTF, and grip strength and diaphragmatic ultrasound (P < 0.01). Furthermore, it was observed that the amalgamation of grip strength and diaphragmatic ultrasound significantly enhanced the diagnostic accuracy of ICU-AW in patients who are critically ill. Conclusion: Grip strength, DE, DTF, and the combined use of grip strength with diaphragm ultrasound demonstrated diagnostic efficacy in ICU-AW. Notably, the integration of grip strength with diaphragm ultrasound exhibited a heightened capacity to enhance the diagnostic value specifically in patients diagnosed who are critically ill with ICU-AW.
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In the original publication [...].
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MicroRNAs (miRNAs) play important roles in drug tolerance and regulating pain. The purpose of the present study is to explore the regulatory mechanism of miR-124-3p on dezocine tolerance against pain in a rat model. The expression of miR-124-3p and TRAF6 in spinal cord of rats was detected by quantitative reverse-transcription PCR. The paw withdrawal latency (PWL) and maximal potential efficiency % of rats were detected by PWL assay. The levels of IL-1ß and TNF-α in spinal cord tissues of rats were measured by ELISA assay. The interaction between TRAF6 and miR-124-3p was predicted by TargetScan software (http://www.targetscan.org) and confirmed by the dual-luciferase reporter assay. The protein level of TRAF6 was determined by western blot. MiR-124-3p expression was highly downregulated in a dezocine-resistant model. MiR-124-3p overexpression could alleviate dezocine tolerance in rats. TRAF6 expression was significantly upregulated in a dezocine-resistant model. MiR-124-3p targeted TRAF6 and TRAF6 was negatively modulated by miR-124-3p. In addition, overexpression of TRAF6 could reverse the inhibitory effects of miR-124-3p on dezocine tolerance. Overexpression of miR-124-3p alleviates dezocine tolerance against pain via regulating TRAF6 in a rat model, providing a possible solution to address dezocine tolerance in clinical.
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Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Tolerância a Medicamentos/genética , MicroRNAs/metabolismo , Dor/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Tetra-Hidronaftalenos/farmacologia , Analgésicos/farmacologia , Animais , Modelos Animais de Doenças , Regulação da Expressão Gênica/genética , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
Computer-aided detection (CADe) systems play a crucial role in pulmonary nodule detection via chest radiographs (CXRs). A two-stage CADe scheme usually includes nodule candidate detection and false positive reduction. A pure deep learning model, such as faster region convolutional neural network (faster R-CNN), has been successfully applied for nodule candidate detection via computed tomography (CT). The model is yet to achieve a satisfactory performance in CXR, because the size of the CXR is relatively large and the nodule in CXR has been obscured by structures such as ribs. In contrast, the CNN has proved effective for false positive reduction compared to the shallow method. In this paper, we developed a CADe scheme using the balanced CNN with classic candidate detection. First, the scheme applied a multi-segment active shape model to accurately segment pulmonary parenchyma. The grayscale morphological enhancement technique was then used to improve the conspicuity of the nodule structure. Based on the nodule enhancement image, 200 nodule candidates were selected and a region of interest (ROI) was cropped for each. Nodules in CXR exhibit a large variation in density, and rib crossing and vessel tissue usually present similar features to the nodule. Compared to the original ROI image, the nodule enhancement ROI image has potential discriminative features from false positive reduction. In this study, the nodule enhancement ROI image, corresponding segmentation result, and original ROI image were encoded into a red-green-blue (RGB) color image instead of the duplicated original ROI image as input of the CNN (GoogLeNet) for false positive reduction. With the Japanese Society of Radiological Technology database, the CADe scheme achieved high performance of the published literatures (a sensitivity of 91.4 % and 97.1 %, with 2.0 false positives per image (FPs/image) and 5.0 FPs/image, respectively) for nodule cases.
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Neoplasias Pulmonares , Nódulo Pulmonar Solitário , Humanos , Pulmão , Neoplasias Pulmonares/diagnóstico por imagem , Redes Neurais de Computação , Interpretação de Imagem Radiográfica Assistida por Computador , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios XRESUMO
Silicon photonics is an enabling technology that provides integrated photonic devices and systems with low-cost mass manufacturing capability. It has attracted increasing attention in both academia and industry in recent years, not only for its applications in communications, but also in sensing. One important issue of silicon photonics that comes with its high integration density is an interface between its high-performance integrated waveguide devices and optical fibers or free-space optics. Surface grating coupler is a preferred candidate that provides flexibility for circuit design and reduces effort for both fabrication and alignment. In the past decades, considerable research efforts have been made on in-plane grating couplers to address their insufficiency in coupling efficiency, wavelength sensitivity and polarization sensitivity compared with out-of-plane edge-coupling. Apart from improved performances, new functionalities are also on the horizon for grating couplers. In this paper, we review the current research progresses made on grating couplers, starting from their fundamental theories and concepts. Then, we conclude various methods to improve their performance, including coupling efficiency, polarization and wavelength sensitivity. Finally, we discuss some emerging research topics on grating couplers, as well as practical issues such as testing, packaging and promising applications.
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A large amount of azo dye wastewater is discharged into the environment, with serious risks to ecosystems and human health. Therefore, the development of treatment technology of azo dye wastewater was of practical significance. Photocatalytic methods showed promising application prospects due to easy to implement and effective. In this study, layered black phosphorus nanosheet (LBP) was used as a catalyst through liquid phase exfoliation method. Methyl orange (MO) was employed as a model azo dye to investigate the catalytic mechanism of LBP. The dominant transient species involved in the photocatalytic reaction was probed by quenching and fluorescence probe experiments. Degradation pathways of MO were proposed according to degradation products identified by the liquid chromatography-mass spectrometry. The results showed that degradation rate (kobs) of MO at acidic condition (pH=3.0) or alkaline condition (pH=11.0) was higher than that at neutral condition (pH=7.0). Degradation pathways of MO included that the azo bond was attacked by hydroxyl radicals (·OH) photogenerated by the LBP, and the intermediate products were further oxidized by ·OH to produce N, N-dimethyl-4-(2-p-phenylmethylhydrazine) aniline, 2-(dimethylamino)-5-((4(dimethylamino) phenyl) diazenyl) phenol and N, N-dimethyl-4-nitroaniline.