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1.
Sensors (Basel) ; 17(9)2017 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-29358567

RESUMEN

Gaofen-4 is China's first geosynchronous orbit high-definition optical imaging satellite with extremely high temporal resolution. The features of staring imaging and high temporal resolution enable the super-resolution of multiple images of the same scene. In this paper, we propose a super-resolution (SR) technique to reconstruct a higher-resolution image from multiple low-resolution (LR) satellite images. The method first performs image registration in both the spatial and range domains. Then the point spread function (PSF) of LR images is parameterized by a Gaussian function and estimated by a blind deconvolution algorithm based on the maximum a posteriori (MAP). Finally, the high-resolution (HR) image is reconstructed by a MAP-based SR algorithm. The MAP cost function includes a data fidelity term and a regularized term. The data fidelity term is in the L2 norm, and the regularized term employs the Huber-Markov prior which can reduce the noise and artifacts while preserving the image edges. Experiments with real Gaofen-4 images show that the reconstructed images are sharper and contain more details than Google Earth ones.

2.
Front Oncol ; 14: 1289555, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38313797

RESUMEN

Background: The novel International Association for the Study of Lung Cancer (IASLC) grading system suggests that poorly differentiated invasive pulmonary adenocarcinoma (IPA) has a worse prognosis. Therefore, prediction of poorly differentiated IPA before treatment can provide an essential reference for therapeutic modality and personalized follow-up strategy. This study intended to train a nomogram based on CT intratumoral and peritumoral radiomics features combined with clinical semantic features, which predicted poorly differentiated IPA and was tested in independent data cohorts regarding models' generalization ability. Methods: We retrospectively recruited 480 patients with IPA appearing as subsolid or solid lesions, confirmed by surgical pathology from two medical centers and collected their CT images and clinical information. Patients from the first center (n =363) were randomly assigned to the development cohort (n = 254) and internal testing cohort (n = 109) in a 7:3 ratio; patients (n = 117) from the second center served as the external testing cohort. Feature selection was performed by univariate analysis, multivariate analysis, Spearman correlation analysis, minimum redundancy maximum relevance, and least absolute shrinkage and selection operator. The area under the receiver operating characteristic curve (AUC) was calculated to evaluate the model performance. Results: The AUCs of the combined model based on intratumoral and peritumoral radiomics signatures in internal testing cohort and external testing cohort were 0.906 and 0.886, respectively. The AUCs of the nomogram that integrated clinical semantic features and combined radiomics signatures in internal testing cohort and external testing cohort were 0.921 and 0.887, respectively. The Delong test showed that the AUCs of the nomogram were significantly higher than that of the clinical semantic model in both the internal testing cohort(0.921 vs 0.789, p< 0.05) and external testing cohort(0.887 vs 0.829, p< 0.05). Conclusion: The nomogram based on CT intratumoral and peritumoral radiomics signatures with clinical semantic features has the potential to predict poorly differentiated IPA manifesting as subsolid or solid lesions preoperatively.

3.
Clin Lab ; 59(9-10): 985-92, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24273920

RESUMEN

BACKGROUND: Low birth weight (LBW) might be a risk factor for acquiring lower respiratory tract infections (LRTIs) associated with disease related complications in early childhood. HFMD, a frequent viral infection in southern China, is a leading cause of lower respiratory tract infections in children. We analyzed whether LBW is a risk factor for children with HFMD to develop lower respiratory tract infections. METHODS: A total of 298 children with HFMD, admitted to a hospital in Qingyuan city, Guangdong province, were recruited. Demographic data and clinical parameters such as serum glucose level and inflammatory markers including peripheral white blood cell count, serum C-reactive protein, and erythrocyte sedimentation rate were routinely collected on admission. Birth weight data were derived from birth records. RESULTS: Mean birth weight (BW) was 167 g lower in patients with HFMD and LRTIs as compared to patients with solely HFMD (p = 0.022) and the frequency of birth weight below the tenth percentile was significantly higher in patients with HFMD and LRTIs (p = 0.002). CONCLUSIONS: The results of the study show that low birth weight is associated with a higher incidence of lower respiratory tract infections in young children with HFMD.


Asunto(s)
Enfermedad de Boca, Mano y Pie/complicaciones , Recién Nacido de Bajo Peso , Infecciones del Sistema Respiratorio/complicaciones , Biomarcadores/sangre , Glucemia/análisis , Sedimentación Sanguínea , Proteína C-Reactiva/análisis , China/epidemiología , Femenino , Enfermedad de Boca, Mano y Pie/epidemiología , Humanos , Lactante , Recién Nacido , Recuento de Leucocitos , Masculino , Factores de Riesgo
4.
Heliyon ; 9(2): e13151, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36747541

RESUMEN

Positive psychology has recently gained a great momentum, which per se motivated us to scrutinize the correlation between teachers' positive psychological capital (TPPC) and their work engagement (WE). The correlation between these two variables has been discovered to be significant as it can create a friendly educational ambiance for the learners to passionately learn. Although several studies have been conducted regarding the aforementioned variables separately or with regard to some other variables, a study on their bond and importance has remained unaddressed. Therefore, the aim of this study is to find the relationship between TPPC and their WE. The participants of this study were 412 Chinese teachers (including 82 males, and 330 females) of different ages and levels of education. Two online instruments were utilized in this study, namely Positive Psychological Capital Scale and the Utrecht Work Engagement Scale (UWES). The results showed a positive and significant association between these two variables. The implications of this study are finally discussed in light of previous studies. Some implications are also offered to EFL educators.

5.
Sci Total Environ ; 859(Pt 1): 160242, 2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36402314

RESUMEN

This paper studies the influence of carbonaceous components on the optical properties of particulate matter (PM) in biodiesel combustion by conducting a bench test on an electronically controlled high-pressure common-rail diesel engine. In addition, the PM produced by the combustion of diesel oil, soybean oil methyl ester (SME), waste edible oil methyl ester (WME), and palm oil methyl ester (PME) was collected. The carbonaceous composition and optical properties of diesel and three biodiesel particulates were then analyzed. The obtained results showed that the ratio of organic carbon (OC) to total carbon (TC) in diesel PM was 0.25 and the ratio of OC/EC was 0.33. The OC to TC ratio of biodiesel PM was significantly greater than that of diesel PM, ranging between 0.59 and 0.65, with OC/EC values in the range of 1.44-1.86. The mass absorption cross-section (MAC) values of three kinds of biodiesel particles were all higher than those of diesel particles. When the incident laser wavelength increased, the difference of MAC values among four kinds of fuel particles gradually decreased. The MAC values of all the three biodiesel particles were higher than those of the diesel particles, and the difference between the MAC values of the four fuel particles gradually decreased with the increase of the incident laser wavelength. Afterwards, the "shell-core" model of particles was developed with 80 nm EC sphere as the core. At the two refractive indices, the scattering cross section, absorption cross section, and extinction cross section of the particles decrease with the increase of the incident light wavelength, and the scattering cross section, absorption cross section, and extinction cross section of the particles increase with the increase of the OC coating thickness.


Asunto(s)
Biocombustibles , Emisiones de Vehículos , Emisiones de Vehículos/análisis , Biocombustibles/análisis , Gasolina/análisis , Material Particulado/análisis , Carbono , Ésteres
6.
Environ Sci Pollut Res Int ; 30(9): 22458-22470, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36289128

RESUMEN

Biodiesel combustion particulate matter (PM) is different from diesel combustion PM in terms of microscopic morphology, which directly affects the optical properties of PM. To investigate the effect of the microstructure of biodiesel PM on the extinction characteristics, an experiment was performed on a high-pressure common rail diesel engine to collect PM from three kinds of biodiesel (the main raw materials were soybean oil methyl eater (SME), palm oil methyl eater (PME), and waste cooking oil methyl eater (WME), respectively). The particle size distribution, micro morphology, and extinction characteristics of biodiesel PM were analyzed. Results show that combustion biodiesel reduces PM emissions by up to 84.2%. Compared to PM from diesel, biodiesel PM has a smaller particle size and a higher aggregation degree, which results in weaker light absorption capacity. With the iodine number of biodiesel decreasing, the number concentration of biodiesel PM decreases and the fractal dimension increases, which leads to producing a more complex agglomerate and a consequent reduction in extinction coefficient. The average particle sizes of PM from SME, PME, and WME are 5.1%, 6.7%, and 13.9% lower than that of diesel PM. Compared with diesel combustion PM, the peak absorption coefficients of SME, WME, and PME combustion PM decrease by 8.4%, 11.4%, and 13.3%, respectively. The extinction properties of particles decrease with increasing fractal dimension within the wavelength range of visible light.


Asunto(s)
Biocombustibles , Material Particulado , Material Particulado/análisis , Biocombustibles/análisis , Gasolina/análisis , Emisiones de Vehículos/análisis , Tamaño de la Partícula , Aceite de Soja , Aceite de Palma
7.
Cancer Med ; 12(18): 18460-18469, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37723872

RESUMEN

BACKGROUND: The surgical approach and prognosis for invasive adenocarcinoma (IAC) and minimally invasive adenocarcinoma (MIA) of the lung differ. However, they both manifest as identical ground-glass nodules (GGNs) in computed tomography images, and no effective method exists to discriminate them. METHODS: We developed and validated a three-dimensional (3D) deep transfer learning model to discriminate IAC from MIA based on CT images of GGNs. This model uses a 3D medical image pre-training model (MedicalNet) and a fusion model to build a classification network. Transfer learning was utilized for end-to-end predictive modeling of the cohort data of the first center, and the cohort data of the other two centers were used as independent external validation data. This study included 999 lung GGN images of 921 patients pathologically diagnosed with IAC or MIA at three cohort centers. RESULTS: The predictive performance of the model was assessed using the area under the receiver operating characteristic curve (AUC). The model had high diagnostic efficacy for the training and validation groups (accuracy: 89%, sensitivity: 95%, specificity: 84%, and AUC: 95% in the training group; accuracy: 88%, sensitivity: 84%, specificity: 93%, and AUC: 92% in the internal validation group; accuracy: 83%, sensitivity: 83%, specificity: 83%, and AUC: 89% in one external validation group; accuracy: 78%, sensitivity: 80%, specificity: 77%, and AUC: 82% in the other external validation group). CONCLUSIONS: Our 3D deep transfer learning model provides a noninvasive, low-cost, rapid, and reproducible method for preoperative prediction of IAC and MIA in lung cancer patients with GGNs. It can help clinicians to choose the optimal surgical strategy and improve the prognosis of patients.

8.
Front Psychol ; 13: 883664, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35846615

RESUMEN

One of the most significant issues in the success of language students is communication skills. Due to the high importance of the willingness to communicate in foreign language learning, many researchers are looking for effective factors in raising the level of communication among language learners. Reviewing the literature, the researchers explored the role of language learners' gender, major, age, and proficiency level in their willingness to communicate. To gather the necessary data, the researcher administered a willingness to communicate questionnaire among 860 Chinese english as a foreign language (EFL) students. The results of data analyses demonstrated that gender, major, and age played a significant role in determining language learners' willingness to communicate. However, the findings showed that learners' willingness to communicate could be different in all proficiency levels. The results showed that taking into account factors such as students' gender, background, and age directly helps to improve the willingness to communicate among language learners. Finally, solutions to improve the willingness to communicate are provided.

9.
Front Psychol ; 12: 830402, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35185712

RESUMEN

Teachers' emotional states such as optimism and commitment have long been approved influential in second/foreign language education. Although many correlational investigations have been conducted on teacher optimism and commitment, their interaction and kinship with teachers' work engagement have been largely ignored in the literature. Considering this situation, the present mini-review aims to present the theoretical underpinnings, definitions, dimensions, and conceptualizations of these three important variables taken from positive psychology. Moreover, the present review can offer a number of practical implications for EFL teachers, teacher educators, program designers, school principals, and L2 researchers, and raise their awareness of the impact of inner emotions on teachers' academic performance. Finally, research gaps and future directions are provided for eager researchers to run similar and complementary studies in EFL contexts.

10.
Medicine (Baltimore) ; 98(16): e15238, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31008956

RESUMEN

RATIONALE: Pancreatic carcinosarcoma (PCS) is a very rare pancreatic cancer with an extremely poor prognosis. Interestingly, PCS can coexist with other metachronous malignant cancers. Here we report a case of PCS combined with esophageal cancer (EC). PATIENT CONCERNS: The patient was a 66-year-old man who presented with abdominal pain and progressive nausea. He had undergone esophagectomy for EC 5 years previously. DIAGNOSIS: Both EC and PCS were confirmed via postoperative pathological diagnosis. INTERVENTIONS: Owing to the patient's previous esophagectomy for EC, pancreaticoduodenectomy for the PCS could not be performed. Instead, he underwent cholecystectomy with bile duct-jejunum Roux-en-Y anastomosis and radioactive seed implantation. OUTCOMES: The patient is still alive for >1 year. LESSONS: To our knowledge, this is the first report of PCS combined with EC and thus of metachronous multiple primary carcinoma. A detailed literature review of the clinical and histologic features of PCS reveals important information about the epidemiology and biology of this rare disease.


Asunto(s)
Carcinosarcoma/patología , Neoplasias Primarias Secundarias/patología , Páncreas/patología , Neoplasias Pancreáticas/patología , Anciano , Carcinoma de Células Escamosas/patología , Carcinosarcoma/diagnóstico por imagen , Neoplasias Esofágicas/patología , Esófago/patología , Humanos , Masculino , Neoplasias Primarias Secundarias/diagnóstico por imagen , Neoplasias Pancreáticas/diagnóstico por imagen
11.
Di Yi Jun Yi Da Xue Xue Bao ; 24(9): 1089-90, 2004 Sep.
Artículo en Zh | MEDLINE | ID: mdl-15447876

RESUMEN

OBJECTIVE: To observe the effect of radio frequency ablation (RFA) for treating metrorrhagia. METHOD: In-36 metrorrhagia patients, who failed to respond to both traditional Chinese medicine and western medicine, and who did not seek child-bearing with malignant changes of the uterus shown by gynecological examination, B-ultrasonic, diagnostic curettage, and pathological examination, the width and depth of the uterine cavity were measured while sending the coagulator to the bottom of the uterus, followed by coagulation of the uterine cavity for two times. The whole process was carried out under the supervision of B-ultrasonic, whose strong echo-band was between 0.8 and 1.0 cm. RESULT: Within one year, the effective rate was 100%, and no recurrence was found. CONCLUSION: RFA is easy, economical, safe and efficient in treating metrorrhagia.


Asunto(s)
Ablación por Catéter , Endometrio/cirugía , Metrorragia/cirugía , Adulto , Femenino , Humanos , Persona de Mediana Edad
12.
Di Yi Jun Yi Da Xue Xue Bao ; 24(6): 718-9, 2004 Jun.
Artículo en Zh | MEDLINE | ID: mdl-15201102

RESUMEN

The authors examine the application of laparoscopy in the management of internal hemorrhage in tubal pregnancy in middle-sized and small hospitals. Altogether 76 such cases were collected for a review of the effects of laparoscopic management, and all were treated successfully without any complications. Laparoscopy causes minimal invasion in the management of internal hemorrhage in tubal pregnancy and may bring about rapid recovery of the patients, but the curative effects depend on the technical competence of the surgeon and the laparoscopic equipment.


Asunto(s)
Hemorragia/cirugía , Laparoscopía/métodos , Embarazo Tubario/cirugía , Adulto , Femenino , Humanos , Persona de Mediana Edad , Embarazo
13.
Dev Comp Immunol ; 34(8): 805-11, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20230853

RESUMEN

The interleukin 2 (IL-2) immunoregulatory cytokine produces its biological effects by binding sequentially to its cell receptor subunits, alpha (CD25), beta (CD122), and common gamma chain (CD132). In this study, we identified the critical amino acid residues of chicken IL-2 (chIL-2) for binding to chicken CD25 (chCD25) by an Ag-capture ELISA, screening of a phage display peptide library, peptide-competitive ELISA and an in vitro T-cell proliferation assay. Specific ligand elution of phage bound to chCD25 and chIL-2 suggested that the P(35)T(36)C(41)T(42)Q(43)L(46)Q(47)C(48)Y(49)L(50)G(51) motif within chIL-2 molecule interacts with the S(99)F(100)C(101)G(102)M(103)P(104)Q(105)T(106)V(107)P(108)S(111)L(112) motif of chCD25 molecule (chCD25(99-112)), whereas the peptide competition ELISA assay showed the residues (27)KIHLELYTPTETQEC(41) within chIL-2 (chIL-2(27-41)) bound to the chCD25 protein. Lymphocyte proliferation and inhibition assays further confirmed that the binding of chIL-2(27-41) to the chCD25 molecule was inhibited by the chCD25(99-112) peptide. Site-specific mutation of the (35)P and (41)C residues in chIL-2(27-41) resulted in the lack of its ability to induce lymphocyte proliferation and binding to the chCD25 molecule. These findings demonstrate that chIL-2(27-41) and chCD25(99-112) are the binding domains between the chIL-2 and chCD25 molecules, and that the residues P(35) and C(41) within chIL-2(27-41) are the critical sites for its bioactivity and interaction with chCD25.


Asunto(s)
Proteínas Aviares/metabolismo , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Interleucina-2/metabolismo , Fragmentos de Péptidos/metabolismo , Linfocitos T/metabolismo , Animales , Proteínas Aviares/genética , Proteínas Aviares/inmunología , Proliferación Celular , Células Cultivadas , Pollos , Clonación Molecular , Cisteína , Interleucina-2/genética , Interleucina-2/inmunología , Subunidad alfa del Receptor de Interleucina-2/genética , Subunidad alfa del Receptor de Interleucina-2/inmunología , Activación de Linfocitos , Mutagénesis Sitio-Dirigida , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/inmunología , Biblioteca de Péptidos , Prolina , Unión Proteica , Dominios y Motivos de Interacción de Proteínas/genética , Bazo/patología , Linfocitos T/inmunología , Linfocitos T/patología
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