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1.
Food Chem ; 356: 129734, 2021 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-33838607

RESUMEN

The effects of NaCl and its partial substitutes (KCl, MgCl2 and CaCl2) on solubility, structural characteristics and aggregation behaviors of myofibrillar protein (MP) from pearl mussel muscle were investigated and compared. MP at 0.6 M NaCl was beneficial to protein unfolding and showed excellent potential functional properties. When NaCl was substituted in low level, MPs also showed good solubility and ordered microstructure as well as NaCl, especially MgCl2 and CaCl2, due to the unfolding of α-helical structures and subsequently exposed tyrosine residues and hydrophobic groups. However, the obviously increased disulfide bonds and hydrophobic interactions in high substitution level indicated the excessive non-sodium salts had negative effects on molecular rearrangement, leading to irregular and overly tight of microstructure. Thus, NaCl partially substituted by KCl, MgCl2 and CaCl2 in low substitution level is promising to improve functional properties of MP in low-sodium meat products.

2.
Cell Death Dis ; 12(4): 381, 2021 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-33833226

RESUMEN

Targeted therapy has greatly improved both survival and prognosis of cancer patients. However, while therapeutic treatment of adenocarcinoma has been advanced greatly, progress in treatment of squamous cell carcinoma (SCC) has been slow and ineffective. Therefore, it is of great importance to decipher mechanisms and identify new drug targets involved in squamous cell carcinoma development. In this study, we demonstrate that E47 plays the distinctive and opposite roles on cell proliferation in adenocarcinoma and squamous cell carcinoma. While E47 suppresses cell proliferation in adenocarcinoma cells, it functions as a oncoprotein to promote cell proliferation and tumor growth of squamous cell carcinoma. Mechanistically, we show that E47 can directly bind to the promoter and transactivate ΔNp63 gene expression in squamous cell carcinoma cells, resulting in upregulation of cyclins D1/E1 and downregulation of p21, and thereby promoting cell proliferation and tumor growth. We further show that expression of E2A (E12/E47) is positively correlated with p63 and that high expression of E2A is associated with poor outcomes in clinical samples of squamous cell carcinoma. These results highlight that the E47-ΔNp63α axis may be potential therapeutic targets for treatment of squamous cell carcinoma.

3.
Carcinogenesis ; 2021 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-33848354

RESUMEN

Autophagy and glycolysis are associated with osimertinib resistance. The energy complement and dynamic balance between these two processes make it difficult to block the process of drug resistance; breaking the complementary relationship between them may effectively overcome drug resistance. However, the exact mechanisms and the key players for regulating autophagy and glycolysis remain unclear. In this study, we demonstrate that autophagy and glycolysis levels in osimertinib-resistant cells were markedly higher than parental cells, and a dynamic balance existed between them. Inhibition of the class III phosphoinositide 3-kinase (PI3K) VPS34 with 3-methyladenine (3-MA) or siRNA can not only inhibit abnormally enhanced autophagy but also inhibit glycolysis by inhibiting the location of epidermal growth factor receptor (EGFR) and the expression of hexokinase II (HK2). By demonstrating that VPS34 is the key player controlling autophagy and glycolysis simultaneously, our study may provide a new strategy for overcoming osimertinib resistance for treatment of EGFR-mutant non-small cell lung cancer (NSCLC patients.).

4.
Preprint | medRxiv | ID: ppmedrxiv-21252420

RESUMEN

BackgroundSustained molecular detection of SARS-CoV-2 RNA in the upper respiratory tract (URT) in mild to moderate COVID-19 is common. We sought to identify host and immune determinants of prolonged SARS-CoV-2 RNA detection. MethodsNinety-five outpatients self-collected mid-turbinate nasal, oropharyngeal (OP), and gingival crevicular fluid (oral fluid) samples at home and in a research clinic a median of 6 times over 1-3 months. Samples were tested for viral RNA, virus culture, and SARS-CoV-2 and other human coronavirus antibodies, and associations were estimated using Cox proportional hazards models. ResultsViral RNA clearance, as measured by SARS-CoV-2 RT-PCR, in 507 URT samples occurred a median (IQR) 33.5 (17-63.5) days post-symptom onset. Sixteen nasal-OP samples collected 2-11 days post-symptom onset were virus culture positive out of 183 RT-PCR positive samples tested. All participants but one with positive virus culture were negative for concomitant oral fluid anti-SARS-CoV-2 antibodies. The mean time to first antibody detection in oral fluid was 8-13 days post-symptom onset. A longer time to first detection of oral fluid anti-SARS-CoV-2 S antibodies (aHR 0.96, 95% CI 0.92-0.99, p=0.020) and BMI [≥] 25kg/m2 (aHR 0.37, 95% CI 0.18-0.78, p=0.009) were independently associated with a longer time to SARS-CoV-2 viral RNA clearance. Fever as one of first three COVID-19 symptoms correlated with shorter time to viral RNA clearance (aHR 2.06, 95% CI 1.02-4.18, p=0.044). ConclusionsWe demonstrate that delayed rise of oral fluid SARS-CoV-2-specific antibodies, elevated BMI, and absence of early fever are independently associated with delayed URT viral RNA clearance.

5.
Artículo en Inglés | MEDLINE | ID: mdl-33711825

RESUMEN

Ox-DNA, as a successful coarse-grain model, has been applied to reproduce the thermodynamic and mechanical properties of both single- and double-stranded DNA. In current simulation, ox-DNA is extended to explore the combined effects of temperature and force on the stability of DNA hairpin and its free energy landscape. Simulations were carried out at different forces and temperatures, at each temperature, a 18-base-pair DNA hairpin dynamically transited between folded state and unfolded state, and the separation between two states is consistent with the full contour length of single-stranded DNA in the unfolded state. Two methods were used to identify the critical force of DNA hairpin at each temperature and the critical forces obtained from two methods were consistent with each other and gradually decreased with the increasing temperature from 300K to 326K. The critical force at 300K is reasonably consistent with the single molecule result of DNA hairpin with the same stem length. The two-state free energy landscape can be elucidated from the probability distribution of DNA hairpin extension and its dependence on the force and temperature is totally different. The increasing temperature not only reduces the free energy barrier, but also alters the position of transition point along the extension coordinate, resulting in the reduction of folding distance and the extension of unfolding distance, but their sum is not obviously dependent on the temperature. Generally, an assumption that the location of transition state in two-state energy landscape is independent of the stretching force is used to analyze the data of the single molecule experiment, but current simulation results indicate that effects of stretching forces on the location of transition state in two-state energy landscape are dependent on temperature. At relatively high temperature, stretching force can also change the location of transition state in the free energy landscape.

6.
Orthop Surg ; 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33719205

RESUMEN

OBJECTIVE: To evaluate the usefulness of a 3D-printed model for transoral atlantoaxial reduction plate (TARP) surgery in the treatment of irreducible atlantoaxial dislocation (IAAD). METHODS: A retrospective review was conducted of 23 patients (13 men, 10 women; mean age 58.17 ± 5.27 years) with IAAD who underwent TARP from January 2015 to July 2017. Patients were divided into a 3D group (12 patients) and a non-3D group (11 patients). A preoperative simulation process was undertaken for the patients in the 3D group, with preselection of the TARP system using a 3D-printed 1:1 scale model, while only imaging data was used for the non-3D group. Complications, clinical outcomes (Japanese Orthopaedic Association [JOA] and visual analogue score [VAS]), and image measurements (atlas-dens interval [ADI], cervicomedullary angle [CMA], and clivus-canal angle [CCA]) were noted preoperatively and at the last follow up. RESULTS: A total of 23 patients with a follow-up time of 16.26 ± 4.27 months were included in the present study. The surgery duration, intraoperative blood loss, and fluoroscopy times in the 3D group were found to be shorter than those in non-3D group, with statistical significance. The surgery duration was 3.29 ± 0.45 h in the 3D group and 4.68 ± 0.90 h in the non-3D group, and the estimated intraoperative blood loss was 131.67 ± 43.03 mL in the 3D group and 185.45 ± 42.28 mL in the non-3D group. No patients received blood transfusions. The intraoperative fluoroscopy times were 5.67 ± 0.89 in the 3D group and 7.91 ± 1.45 in the non-3D group. Preoperatively and at last follow up, JOA and VAS scores and ADI, CCA, and CMA were improved significantly within the two groups. However, no statistical difference was observed between the two groups. However, surgical site infection occurred in 1 patient in the 3D group, who underwent an emergency revision operation of the removal of TARP device and posterior occipitocervical fixation; the patient recovered 2 weeks after the surgery. In 2 patients in the traditional group, a mistake occurred in the placement of screws, with no neurological symptoms related to the misplacement. CONCLUSION: Preoperative surgical simulation using a 3D-printed real-size model is an intuitive and effective aid for TARP surgery for treating IAAD. The 3D-printed biomodel precisely replicated patient-specific anatomy for use in complicated craniovertebral junction surgery. The information was more useful than that available with 3D reconstructed images.

7.
Artículo en Inglés | MEDLINE | ID: mdl-33651298

RESUMEN

OBJECTIVES: It is with a great prospect to develop an auxiliary diagnosis system for dental periapical radiographs based on deep convolutional neural networks (CNNs), and the indications and performances should be investigated. The aim of this study is to train CNNs for lesion detections on dental periapical radiographs, to evaluate performances across disease categories, severity levels, and train strategies. METHODS: Deep CNNs with region proposal techniques were constructed for disease detections on clinical dental periapical radiographs, including decay, periapical periodontitis, and periodontitis, leveled as mild, moderate, and severe. Four strategies were carried out to train corresponding networks with all disease and level categories (baseline), all disease categories (Net A), each disease category (Net B), and each level category (Net C) and validated by a fivefold cross-validation method afterward. Metrics, including intersection over union (IoU), precision, recall, and average precision (AP), were compared across diseases, severity levels, and train strategies by analysis of variance. RESULTS: Lesions were detected with precision and recall generally between 0.5 and 0.6 on each kind of disease. The influence of train strategy, disease category, and severity level were all statistically significant on performances (P < .001). Decay and periapical periodontitis lesions were detected with precision, recall, and AP values less than 0.25 for mild level, while 0.2-0.3 for moderate level and 0.5-0.6 for severe level. Net A performed similar to baseline (P > 0.05 for IoU, precision, and recall), while Net B and Net C performed slightly better than baseline under certain circumstances (P < 0.05), but Net C failed to predict mild decay. CONCLUSIONS: The deep CNNs are able to detect diseases on clinical dental periapical radiographs. This study reveals that the CNNs prefer to detect lesions with severe levels, and it is better to train the CNNs with customized strategy for each disease.

8.
J Prosthet Dent ; 2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33549341

RESUMEN

STATEMENT OF PROBLEM: Existing virtual articulators simulate mandibular movement by using various parameters and are used to design restorations. However, they are not able to reproduce actual patient movements, and the designs of occlusal wear facets by them and by personalized mandibular movement have not been compared. PURPOSE: The purpose of this clinical study was to establish a clinical application protocol for a virtual articulator based on previous research and to evaluate the accuracy of the occlusal wear facets designed by it. MATERIAL AND METHODS: The gypsum casts of 12 participants were scanned with a cast scanner as the original data. A single crown, 3-unit splinted crowns, a 5-unit fixed partial denture, and a fixed complete denture were virtually prepared on the digital mandibular casts by using the Geomagic Studio 2013 software program. High points were created at the wear facets, and corresponding digital wax patterns with occlusal interferences were generated. The exocad software program was used to design corresponding restorations with the copy method. Static (STA restoration) and dynamic (DYN restoration) occlusal adjustments were carried out with the built-in virtual articulator. The mandibular movements of participants were recorded by the novel virtual articulator system, and the occlusal surfaces of the digital wax patterns were adjusted (FUN restoration). The restorations adjusted with the 3 methods were compared with the original data. The mean value and root mean square (RMS) of 3D deviation and positive volumes (V+) in the occlusal direction were measured. Depending on the normality, 1-way ANOVA and the Kruskal-Wallis test were used to analyze the influence of occlusal surface design methods on the morphology of occlusal wear facets (α=.05). RESULTS: The mean deviation of the 4 kinds of STA restorations ranged from 0.19 mm to 0.22 mm, the DYN restorations from 0.13 mm to 0.17 mm, and the FUN restorations from 0.03 mm to 0.09 mm. A significant difference was found between the STA and FUN restorations of the 3-unit splinted crowns and 5-unit fixed partial dentures (Ρ=.013, Ρ=.021). The mean values of 3D deviation and V+ decreased from the STA group to the DYN group and then to the FUN group. The RMS and V+ were statistically similar (Ρ>.05). CONCLUSIONS: The preliminary results of the study indicate that the FUN 3-unit splinted crowns and 5-unit fixed partial dentures designed with the self-developed virtual articulator were better than the STA restorations. The FUN restorations were more coincident with the morphology of the wear facets on the original teeth.

10.
PLoS Biol ; 19(2): e3001113, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33626035

RESUMEN

Transforming growth factor-ß (TGF-ß) signaling plays a critical role in promoting epithelial-to-mesenchymal transition (EMT), cell migration, invasion, and tumor metastasis. ΔNp63α, the major isoform of p63 protein expressed in epithelial cells, is a key transcriptional regulator of cell adhesion program and functions as a critical metastasis suppressor. It has been documented that the expression of ΔNp63α is tightly controlled by oncogenic signaling and is frequently reduced in advanced cancers. However, whether TGF-ß signaling regulates ΔNp63α expression in promoting metastasis is largely unclear. In this study, we demonstrate that activation of TGF-ß signaling leads to stabilization of E3 ubiquitin ligase FBXO3, which, in turn, targets ΔNp63α for proteasomal degradation in a Smad-independent but Erk-dependent manner. Knockdown of FBXO3 or restoration of ΔNp63α expression effectively rescues TGF-ß-induced EMT, cell motility, and tumor metastasis in vitro and in vivo. Furthermore, clinical analyses reveal a significant correlation among TGF-ß receptor I (TßRI), FBXO3, and p63 protein expression and that high expression of TßRI/FBXO3 and low expression of p63 are associated with poor recurrence-free survival (RFS). Together, these results demonstrate that FBXO3 facilitates ΔNp63α degradation to empower TGF-ß signaling in promoting tumor metastasis and that the TßRI-FBXO3-ΔNp63α axis is critically important in breast cancer development and clinical prognosis. This study suggests that FBXO3 may be a potential therapeutic target for advanced breast cancer treatment.

11.
World Neurosurg ; 2021 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-33508486

RESUMEN

OBJECTIVE: This study aimed to explore the clinical application of three-dimensional (3D) printing technology in the surgical treatment of congenital scoliosis caused by hemivertebrae. METHODS: Twenty-four patients (11 in the 3D-printing group and 13 in the conventional group) with scoliosis secondary to a single hemivertebra were retrospectively reviewed. All patients underwent hemivertebrectomy and short-segment fixation. Virtual preoperative planning, operation simulation, and intraoperative application of 3D-printed patient-specific templates were performed in the 3D-printing group. Hemorrhage volume, operation time, transfusion, and complications were noted. Radiographic parameters were evaluated preoperatively, postoperatively, and at final follow-up. RESULTS: All patients had different degrees of successfully corrected scoliosis. There was a similar correction of the Cobb angle postoperatively between the 2 groups. The operation time, blood loss, transfusion, time for the insertion of each screw, accuracy of screw placement, and complication rate in the 3D-printing group were significantly superior to those in the control group. No patient experienced major complications. No significant correction loss or instrument dysfunction was observed during follow-up. CONCLUSIONS: As a viable and effective auxiliary technology, 3D printing makes it possible for surgery to meet both surgeon-specific and patient-specific requirements. 3D-printed individualized templates allow surgery for the correction of congenital scoliosis to enter a new stage of personalized precision surgery.

12.
J Int Med Res ; 49(1): 300060520982829, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33496629

RESUMEN

Bullous pemphigoid (BP) is an autoimmune disease that requires immunosuppressive therapy. Systemic corticosteroids are considered the standard treatment for moderate-to-severe BP. Kaposi's sarcoma (KS) is a rare multifocal endothelial tumour that affects the skin, mucosa and viscera. As an angioproliferative disease of obscure aetiopathogenesis and histogenesis, KS is associated with human herpesvirus 8 (HHV-8). This current case report describes a rare occurrence of extensive cutaneous KS in a 60-year-old Chinese male patient after oral methylprednisolone treatment for BP with an emphasis on its pathological characterization. A total of more than 40 nodules were found on his trunk and lower limbs covering more than 20% of his body surface area. Immunohistochemical staining of biopsy samples from the lesion showed the patient was positive for HHV-8, CD31, CD34, XIIIa, ERG and Ki-67. The Epstein-Barr virus test showed the patient tested negative for immunoglobulin (Ig)A and IgM, but was positive for IgG. Immunosuppression associated with the treatment for BP may activate a latent HHV-8 infection and induce the development of KS.

13.
Medicine (Baltimore) ; 100(2): e24016, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33466145

RESUMEN

BACKGROUND: The purpose of this study is to determine the therapeutic efficacy of bi-level continuous positive airway pressure (BIPAP) intervention in patients with type II respiratory failure due to acute exacerbation of chronic obstructive pulmonary disease (COPD). METHODS: This review will only include randomized controlled trials (RCTs). The search strategy will be applied to 4 Chinese databases: China National Knowledge Infrastructure (CNKI), Wanfang Database, Chinese Science and Technology Journal Database (VIP), and Chinese Biomedical Literature Database (SinoMed); and 5 foreign literature databases: PubMed, Cochrane Library, Springer, EBSCO, and Web of Science. RCTs published from inception to October 2020 will be included. The 2 researchers will independently screen and extract the data and assess quality. The main results obtained through blood gas analysis and equipment observation, heterogeneity assessment, sensitivity analysis, funnel chart synthesis, data synthesis, and grouping analysis will be carried out using Review Manager 5.4 software. The trial sequential analysis will be completed using TSA v0.9 developed by the CTU at the Copenhagen Clinical Trial Center. RESULTS: In the current meta-analysis, we will provide more practical and targeted results for the therapeutic efficacy of BIPAP in patients with type II respiratory failure due to acute exacerbation of COPD. CONCLUSION: This study will provide new evidence for the therapeutic efficacy of BIPAP in patients with type II respiratory failure due to acute exacerbation of COPD. REGISTRATION NUMBER: INPLASY2020110003 (DOI:10.37766/inplasy2020.11.0003).


Asunto(s)
Presión de las Vías Aéreas Positiva Contínua/métodos , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Insuficiencia Respiratoria/etiología , Insuficiencia Respiratoria/terapia , Análisis de los Gases de la Sangre , Humanos , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Ensayos Clínicos Controlados Aleatorios como Asunto , Proyectos de Investigación
14.
J Oral Rehabil ; 2021 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-33486815

RESUMEN

Common impressions cannot accurately duplicate the dental occlusion under occlusal force due to tooth displacement and mandibular deformation. To establish new methods to construct virtual intercuspal occlusion and assess their construction accuracy. The intraoral occlusal contacts of posterior teeth of 15 subjects were recorded with 8 µm and 100 µm articulating paper, respectively, and the marked teeth and buccal bite data were scanned with an intraoral scanner. The virtual dental occlusions were separately determined by buccal bite registration (BBR) method, and 3 new methods, namely segmented tooth registration (STR), occlusal contact areas (marked by 8 µm articulating paper) registration (OCR) and mixing registration (MR) methods. With the intraoral contact areas marked by 100 µm articulating paper set as reference and contact areas of the 4 virtual occlusions as tests, sensitivity, positive predictive value (PPV) and the ratio of overlapping areas were calculated. Kruskal-Wallis test or 1-way ANOVA was used to analyse the difference among groups. The sensitivity ranged from 0.69 to 0.94 and the PPV from 0.67 to 0.90. Sensitivity of OCR group and PPV of STR and OCR groups were different from that of BBR group at overlapping threshold of 50% (P = .028, .028 and .006). There was statistical difference of the ratio of overlapping areas over reference areas, and the values of STR and OCR groups were higher than that of BBR group (P = .045 and .021). The ability of STR and OCR methods to construct virtual intercuspal occlusion was better than BBR method.

15.
J Hazard Mater ; 404(Pt A): 124109, 2021 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-33049641

RESUMEN

A new process of NOx removal from flue gas, using an integrated system of oxidation-absorption-biological reduction (OABR), is introduced. The experimental results show that increasing the NOx oxidation ratio in flue gas can effectively improve the NOx removal efficiency of the OABR system. The NOx removal efficiency could reach 98.8% with 0.02 M NaHCO3 as the chemical absorbent and under the condition of the optimal NOx oxidation ratio of 50%. During stable operation, the OABR system could maintain a high NOx removal efficiency (above 94%) under the following conditions: 1-8 vol% (104-8 × 104 ppmv) O2, 200-800 ppmv NOx, 0.5-1.5 L/min gas flow rate and 100-800 ppmv SO2. The nitrogen equilibrium results showed that about 59% of the nitrogen in the inlet NOx were transformed to N2 through microbial denitrification, 37% of the nitrogen were converted to biological nitrogen for microbial growth, and only 1.1% of the nitrogen remained in the liquid phase. This new approach has an excellent NOx removal performance and great potential for industrial application.

16.
J Mech Behav Biomed Mater ; 115: 104255, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33340775

RESUMEN

Subtractive manufacturing has become the dominant method in fabricating zirconia dental restorations while additive manufacturing is emerging as a potential alternative. The aim of this in vitro study was to investigate the performance of stereolithography (SLA) and milling in fabricating monolithic zirconia crowns with different finish line designs. Full-contour crowns with three finish lines (chamfer, rounded shoulder, knife-edge) were designed and fabricated by SLA and milling. Fabrication accuracy was accessed by 3D deviation analysis and margin quality was characterized under microscopes. The obtained root mean square value was significantly influenced by finish line design (P < 0.05) but not by fabrication method (P>0.05). However, the color-difference map showed crowns fabricated by SLA and milling had different error distribution in external surfaces. SLA-printed crowns exhibited margins of rounded line angle and without small flaws, although large chippings were found in knife-edged crowns. In milling group, crowns showed margins of sharp line angle and with separate chippings. More and larger margin chippings were found in knife-edged crowns by milling. The results indicate that SLA and milling can fabricate monolithic zirconia crowns of comparable accuracy and knife-edged crowns are prone to large margin chippings by either of the two manufacturing methods.

17.
Angew Chem Int Ed Engl ; 60(17): 9368-9373, 2021 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-33368944

RESUMEN

N-type conjugated polymers as the semiconducting component of organic electrochemical transistors (OECTs) are still undeveloped with respect to their p-type counterparts. Herein, we report two rigid n-type conjugated polymers bearing oligo(ethylene glycol) (OEG) side chains, PgNaN and PgNgN, which demonstrated an essentially torsion-free π-conjugated backbone. The planarity and electron-deficient rigid structures enable the resulting polymers to achieve high electron mobility in an OECT device of up to the 10-3  cm2 V-1 s-1 range, with a deep-lying LUMO energy level lower than -4.0 eV. Prominently, the polymers exhibited a high device performance with a maximum dimensionally normalized transconductance of 0.212 S cm-1 and the product of charge-carrier mobility µ and volumetric capacitance C* of 0.662±0.113 F cm-1 V-1 s-1 , which are among the highest in n-type conjugated polymers reported to date. Moreover, the polymers are synthesized via a metal-free aldol-condensation polymerization, which is beneficial to their application in bioelectronics.

18.
IEEE Trans Med Imaging ; PP2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33259294

RESUMEN

Forensic odontology is regarded as an important branch of forensics dealing with human identification based on dental identification. This paper proposes a novel method that uses deep convolution neural networks to assist in human identification by automatically and accurately matching 2-D panoramic dental X-ray images. Designed as a top-down architecture, the network incorporates an improved channel attention module and a learnable connected module to better extract features for matching. By integrating associated features among all channel maps, the channel attention module can selectively emphasize interdependent channel information, which contributes to more precise recognition results. The learnable connected module not only connects different layers in a feed-forward fashion but also searches the optimal connections for each connected layer, resulting in automatically and adaptively learning the connections among layers. Extensive experiments demonstrate that our method can achieve new state-of-the-art performance in human identification using dental images. Specifically, the method is tested on a dataset including 1,168 dental panoramic images of 503 different subjects, and its dental image recognition accuracy for human identification reaches 87.21% rank-1 accuracy and 95.34% rank-5 accuracy. Code has been released on Github. (https://github.com/cclaiyc/TIdentify).

19.
Artículo en Inglés | MEDLINE | ID: mdl-33259685

RESUMEN

Donor-acceptor (D-A) polymers are promising materials for organic electrochemical transistors (OECTs), as they minimize detrimental faradaic side-reactions during OECT operation, yet their steady-state OECT performance still lags far behind their all-donor counterparts. Here, we report three D-A polymers based on the diketopyrrolopyrrole unit that afford OECT performances similar to those of all-donor polymers, hence representing a significant improvement to the previously developed D-A copolymers. In addition to improved OECT performance, DFT simulations of the polymers and their respective hole polarons also revealed a positive correlation between hole polaron delocalization and steady-state OECT performance, providing new insights into the design of OECT materials. More importantly, we demonstrate how polaron delocalization can be tuned directly at the molecular level by selection of the building blocks comprising the polymers' conjugated backbone, thus paving the way for the development of even higher performing OECT polymers.

20.
IEEE Trans Med Imaging ; PP2020 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-33326376

RESUMEN

Due to its noninvasive character, optical coherence tomography (OCT) has become a popular diagnostic method in clinical settings. However, the low-coherence interferometric imaging procedure is inevitably contaminated by heavy speckle noise, which impairs both visual quality and diagnosis of various ocular diseases. Although deep learning has been applied for image denoising and achieved promising results, the lack of well-registered clean and noisy image pairs makes it impractical for supervised learning-based approaches to achieve satisfactory OCT image denoising results. In this paper, we propose an unsupervised OCT image speckle reduction algorithm that does not rely on well-registered image pairs. Specifically, by employing the ideas of disentangled representation and generative adversarial network, the proposed method first disentangles the noisy image into content and noise spaces by corresponding encoders. Then, the generator is used to predict the denoised OCT image with the extracted content features. In addition, the noise patches cropped from the noisy image are utilized to facilitate more accurate disentanglement. Extensive experiments have been conducted, and the results suggest that our proposed method is superior to the classic methods and demonstrates competitive performance to several recently proposed learning-based approaches in both quantitative and qualitative aspects. Code is available at: https://github.com/tsmotlp/DRGAN-OCT.

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