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1.
Anal Chem ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38967251

RESUMEN

As one of the most common cancers, accurate, rapid, and simple histopathological diagnosis is very important for breast cancer. Raman imaging is a powerful technique for label-free analysis of tissue composition and histopathology, but it suffers from slow speed when applied to large-area tissue sections. In this study, we propose a dual-modal Raman imaging method that combines Raman mapping data with microscopy bright-field images to achieve virtual staining of breast cancer tissue sections. We validate our method on various breast tissue sections with different morphologies and biomarker expressions and compare it with the golden standard of histopathological methods. The results demonstrate that our method can effectively distinguish various types and components of tissues, and provide staining images comparable to stained tissue sections. Moreover, our method can improve imaging speed by up to 65 times compared to general spontaneous Raman imaging methods. It is simple, fast, and suitable for clinical applications.

2.
Small ; 20(23): e2308005, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38148319

RESUMEN

The conversion of CO2 into valuable carbon-based products using clean and renewable solar energy has been a significant challenge in photocatalysis. It is of paramount importance to develop efficient photocatalysts for the catalytic conversion of CO2 using visible light. In this study, the Ni-MOF-74 material is successfully modified to achieve a highly porous structure (Ni-74-Am) through temperature and solvent modulation. Compared to the original Ni-MOF-74, Ni-74-Am contains more unsaturated Ni active sites resulting from defects, thereby enhancing the performance of CO2 photocatalytic conversion. Remarkably, Ni-74-Am exhibits outstanding photocatalytic performance, with a CO generation rate of 1380 µmol g-1 h-1 and 94% CO selectivity under visible light, significantly surpassing the majority of MOF-based photocatalysts reported to date. Furthermore, experimental characterizations reveal that Ni-74-Am has significantly higher efficiency of photogenerated electron-hole separation and faster carrier migration rate for photocatalytic CO2 reduction. This work enriches the design and application of defective MOFs and provides new insights into the design of MOF-based photocatalysts for renewable energy and environmental sustainability. The findings of this study hold significant promise for developing efficient photocatalysts for CO2 reduction under visible-light conditions.

3.
J Environ Sci (China) ; 139: 123-137, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38105041

RESUMEN

The fate of 2-nitrobenzaldehyde (2-NBA) is of interest in atmospheric chemistry as it is a semi-volatile organic compound with high photosensitivity. This study presents a quantum chemical study of the gas-phase reactions of 2-NBA photo-excitation and OH-oxidation in the absence and presence of small TiO2 clusters. To further understand the unknown photolysis mechanism, the photo-reaction pathways of ground singlet state and the lying excited triplet state of 2-NBA were investigated including the initial and subsequent reactions of proton transfer, direct CO, NO2, and HCO elimination routes in the presence of O2 and NO. Meanwhile, the OH-mediated degradation of 2-NBA proceeded via five H-extraction and six OH-addition channels by indirect mechanism, which follows a succession of reaction steps initiated by the formation of weakly stable intermediate complexes. The H-extraction from the -CHO group was the dominant pathway with a negative activation energy of -1.22 kcal/mol. The calculated rate coefficients at 200-600 K were close to the experimental data in literature within 308-352 K, and the kinetic negative temperature independence was found in both experimental literature and computational results. Interestingly, 2-NBA was favored to be captured onto small TiO2 clusters via six adsorption configurations formed via various combination of three types of bonds of Ti···O, Ti···C, and O···H between the molecularly adsorbed 2-NBA and TiO2 clusters. Comparison indicted that the chemisorptions of aldehyde oxygen have largest energies. The results suggested adsorption conformations have a respectable impact on the catalysis barrier. This study is significant for understanding the atmospheric chemistry of 2-nitrobenzaldehyde.


Asunto(s)
Oxígeno , Adsorción , Temperatura , Oxígeno/química , Catálisis
4.
Anal Chem ; 95(5): 3019-3027, 2023 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-36706440

RESUMEN

Breast cancer is the most commonly diagnosed cancer type worldwide. Overexpression of human epidermal growth factor receptor 2 (HER2) is an important subtype of breast cancer and results in an increased risk of recurrence and metastasis in patients. At present, immunohistochemistry (IHC) is used to detect the expression of HER2 in breast cancer tissues as the golden standard. However, IHC has some shortcomings, such as large subjective impact, long time consumption, expensive reagents, etc. In this paper, a combined morphological and spectroscopic diagnostic method based on label-free surface-enhanced Raman scattering (SERS) for HER2 expression in breast cancer is proposed. It can not only quantitively detect HER2 expression in breast cancer tissues by spectroscopic measurements but also give morphological images reflecting the distribution of HER2 in tissues. The results show that the consistency between this method and IHC is 95% and achieves the annotation of tumor regions on tissue sections. This method is time-consuming, quantifiable, intuitive, scalable, and easy to understand. Combined with deep learning approaches, it is expected to promote the development of clinical detection and diagnosis technology for breast cancer and other cancers.


Asunto(s)
Neoplasias de la Mama , Espectrometría Raman , Humanos , Femenino , Neoplasias de la Mama/patología , Receptor ErbB-2/metabolismo , Inmunohistoquímica , Biomarcadores de Tumor
5.
Chemphyschem ; 24(10): e202300021, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-36781393

RESUMEN

The degradation and transformation of iodinated alkanes are crucial in the iodine chemical cycle in the marine boundary layer. In this study, MP2 and CCSD(T) methods were adopted to study the atmospheric transformation mechanism and degradation kinetic properties of CH3 I and CH3 CH2 I mediated by ⋅OH radical. The results show that there are three reaction mechanisms including H-abstraction, I-substitution and I-abstraction. The H-abstraction channel producing ⋅CH2 I and CH3 C ⋅ HI radicals are the main degradation pathways of CH3 I and CH3 CH2 I, respectively. By means of the variational transition state theory and small curvature tunnel correction method, the rate constants and branching ratios of each reaction are calculated in the temperature range of 200-600 K. The results show that the tunneling effect contributes more to the reaction at low temperatures. Theoretical reaction rate constants of CH3 I and CH3 CH2 I with ⋅OH are calculated to be 1.42×10-13 and 4.44×10-13  cm3 molecule-1 s-1 at T=298 K, respectively, which are in good agreement with the experimental values. The atmospheric lifetimes of CH3 I and CH3 CH2 I are evaluated to be 81.51 and 26.07 day, respectively. The subsequent evolution mechanism of ⋅CH2 I and CH3 C ⋅ HI in the presence of O2 , NO and HO2 indicates that HCHO, CH3 CHO, and I-atom are the main transformation end-products. This study provides a theoretical basis for insight into the diurnal conversion and environmental implications of iodinated alkanes.

6.
J Phys Chem A ; 127(25): 5402-5413, 2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37311006

RESUMEN

Nitrous acid (HONO) is hazardous to the human respiratory system, and the hydrolysis of NO2 is the source of HONO. Hence, the investigation on the removal and transformation of HONO is urgently established. The effects of amide on the mechanism and kinetics of the formation of HONO with acetamide, formamide, methylformamide, urea, and its clusters of the catalyst were studied theoretically. The results show that amide and its small clusters reduce the energy barrier, the substituent improves the catalytic efficiency, and the catalytic effect order is dimer > monohydrate > monomer. Meanwhile, the clusters composed of nitric acid (HNO3), amides, and 1-6 water molecules were investigated in the amide-assisted nitrogen dioxide (NO2) hydrolysis reaction after HONO decomposes by combining the system sampling technique and density functional theory. The study on thermodynamics, intermolecular forces, optics properties of the clusters, as well as the influence of humidity, temperature, atmospheric pressure, and altitude shows that amide molecules promote the clustering and enhance the optical properties. The substituent facilitates the clustering of amide and nitric acid hydrate and lowers the humidity sensitivity of the clusters. The findings will help to control the atmospheric aerosol particle and then reduce the harm of poisonous organic chemicals on human health.

7.
Int Ophthalmol ; 43(2): 491-501, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35932419

RESUMEN

PURPOSE: To compare the postoperative visual outcomes of two different preoperative corneal incision schemes in TECNIS toric intraocular lens (IOL) implantation. METHODS: In this randomized controlled study, patients with preoperative corneal astigmatism greater than 1.0 diopter (D) were included. These patients were grouped according to the different preoperative schemes: steep-axis group and minimum-residual refractive astigmatism group. The outcome measurements were the residual refractive astigmatism, visual acuity, changes of corneal astigmatism, and high-order aberration at 1 month postoperatively. RESULTS: This study consisted of 90 eyes (45 eyes steep-axis group, 45 eyes minimum-residual refractive astigmatism group). 1 month after surgery, the refractive astigmatism was statistically lower in the minimum-residual refractive astigmatism group compared with the steep-axis group (0.58 ± 0.40D vs 0.38 ± 0.37D, P = 0.021). The minimum-residual refractive astigmatism group had a smaller difference vector (0.56 ± 0.38D vs 0.36 ± 0.35D; P = 0.047) and a smaller prediction error (0.60 ± 0.44D vs 0.37 ± 0.35D; P = 0.004). In the steep-axis group, corneal astigmatism significantly decreased compared with preoperative value (1.65 ± 0.57D vs 1.17 ± 0.64D; P < 0.001). In the minimum-residual refractive astigmatism group, the changes of corneal astigmatism before and after surgery were not significant. Moreover, total aberration and second astigmatism in ocular aberration were lower in the minimum-residual refractive astigmatism group compared with the steep-axis group (1.86 ± 1.09 vs 1.37 ± 0.95; P = 0.035 and 0.47 ± 0.28 vs 0.31 ± 0.19; P = 0.015, respectively). CONCLUSION: Minimum-residual refractive astigmatism incision had better astigmatism correction and more accurate prediction. The corneal astigmatism was stable 1 month after surgery. It might lead to better visual quality in the early postoperative stage. Trial registration number for prospectively registered trials: clinicaltrials.gov NCT04006912, 07/02/2019.


Asunto(s)
Astigmatismo , Enfermedades de la Córnea , Lentes Intraoculares , Facoemulsificación , Humanos , Implantación de Lentes Intraoculares , Astigmatismo/cirugía , Refracción Ocular , Enfermedades de la Córnea/cirugía , Córnea
8.
Phys Chem Chem Phys ; 24(43): 26668-26683, 2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36300380

RESUMEN

Halogenated phenols are highly toxic chemicals with serious health risks, and the removal of these persistent environmental pollutants remains a challenge. Based on quantum chemistry calculations, the homogeneous/heterogeneous degradation mechanism and kinetics of C6X5OH (X = F, Cl, and Br) initiated by ˙OH radicals in the gas phase and TiO2 cluster surfaces are investigated in this work. Four ˙OH-addition and one proton-coupled electron-transfer (PCET) reaction channels for each halogenated phenol were found and the ˙OH-addition channels were more favorable than the PCET pathway without TiO2 clusters. At 296 K, the calculated total rate constant for ˙OH with C6F5OH in the atmosphere well agreed with the limited experimental data of (6.88 ± 1.37) × 10-12 cm3 molecule-1 s-1. The lifetimes of C6F5OH, C6Cl5OH, and C6Br5OH were about 12.04-12.86 h at 296 K, which favored their medium-range transport in the atmosphere. In the presence of (TiO2)n clusters (n = 4, 6, 8, 12, and 16), the PCET mechanism for hydrogen transfer reaction of C6F5OH with ˙OH radicals was changed from the previous four-electron/three-center into four-electron/two-center, which results in the PCET pathway becoming more favorable than the ˙OH-addition channels. Meanwhile, the heterogeneous degradation rate constants of C6F5OH were accelerated by more than 10 orders of magnitude within 200-430 K compared with those of the naked reaction. The effects of (TiO2)n cluster (n = 4, 6, 8, 12, and 16) size on the degradation rates were analyzed at 200-430 K, and the reaction on the (TiO2)8 cluster had a faster rate. The subsequent reactions including the bond cleavage of the benzene ring and O2 addition or abstraction were studied. This work provides new insights into halogenated aromatic atmospheric chemistry and nanoscale TiO2 photocatalysis in air or wastewater management.


Asunto(s)
Gases , Radical Hidroxilo , Cinética , Radical Hidroxilo/química , Fenoles
9.
J Phys Chem A ; 126(42): 7750-7762, 2022 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-36253764

RESUMEN

Amino acids are important nitrogen-containing compounds and organic carbon components that exist widely in the atmosphere. The formation of atmospheric aerosols is affected by their interactions with amides. The dimers formed by glutamic acid (Glu) or protonated glutamic acid (Glu+) with three kinds of amide molecules (formamide FA, acetamide AA, urea U) and the hydrated clusters formed by Glu or Glu+, U molecules along with one to six water molecules were systematically studied at the M06-2X/6-311++G(3df,3pd) level. U is predicted to form a more stable structure with Glu/Glu+ than FA and AA by thermodynamics. If the concentration ratio of FA to U is less than 104, U will play a critical role in NPF. The degree of hydration in Glu+-mU-nW is higher than that of Glu-mU-nW (m = 0, 1; n = 0-6) clusters. Notably, Glu contributes more to the Rayleigh scattering properties than glutaric acid and sulfuric acid, and thus may lead to the destruction of atmospheric visibility. This study is helpful to better understand the properties of organic aerosols containing amino acids or amides.


Asunto(s)
Amidas , Agua , Agua/química , Amidas/química , Ácido Glutámico , Ácidos Sulfúricos/química , Aerosoles/química , Modelos Teóricos , Aminoácidos , Aminas , Formamidas , Urea , Acetamidas , Carbono , Nitrógeno
10.
Chem Phys Lett ; 800: 139663, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35529782

RESUMEN

In order to control COVID-19, rapid and accurate detection of the pathogenic, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an urgent task. The target spike proteins of SARS-CoV-2 have been detected experimentally via Raman spectroscopy. However, there lacks high-accuracy theoretical Raman spectra of the spike proteins to as a standard reference for the clinic diagnostic purpose. In this paper, we propose a large fragment method to construct the high-precision Raman spectra for the spike proteins. The large fragment method not only reduces the calculation error but also improves the accuracy of the protein Raman spectra by completely calculating the interactions within the large fragment. The Pearson correlation coefficient of theoretical Raman spectra is greater than 0.929 or more. Compared with the experimental spectra, the characteristic patterns are easily visible. This work provides a detection standard for the spike proteins which shall bring a step closer to the fast recognition of SARS-CoV-2 via Raman spectroscopy method.

11.
Clin Exp Ophthalmol ; 50(7): 714-723, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35704615

RESUMEN

BACKGROUND: To evaluate artificial intelligence (AI) models based on objective indices and raw corneal data from the Scheimpflug Pentacam HR system (OCULUS Optikgeräte GmbH, Wetzlar, Germany) for the detection of clinically unaffected eyes in patients with asymmetric keratoconus (AKC) eyes. METHODS: A total of 1108 eyes of 1108 patients were enrolled, including 430 eyes from normal control subjects, 231 clinically unaffected eyes from patients with AKC, and 447 eyes from keratoconus (KC) patients. Eyes were divided into a training set (664 eyes), a test set (222 eyes) and a validation set (222 eyes). AI models were built based on objective indices (XGBoost, LGBM, LR and RF) and entire corneal raw data (KerNet). The discriminating performances of the AI models were evaluated by accuracy and the area under the ROC curve (AUC). RESULTS: The KerNet model showed great overall discriminating power in the test (accuracy = 94.67%, AUC = 0.985) and validation (accuracy = 94.12%, AUC = 0.990) sets, which were higher than the index-derived AI models (accuracy = 84.02%-86.98%, AUC = 0.944-0.968). In the test set, the KerNet model demonstrated good diagnostic power for the AKC group (accuracy = 95.24%, AUC = 0.984). The validation set also proved that the KerNet model was useful for AKC group diagnosis (accuracy = 94.12%, AUC = 0.983). CONCLUSIONS: KerNet outperformed all the index-derived AI models. Based on the raw data of the entire cornea, KerNet was helpful for distinguishing clinically unaffected eyes in patients with AKC from normal eyes.


Asunto(s)
Queratocono , Inteligencia Artificial , Córnea , Paquimetría Corneal , Topografía de la Córnea/métodos , Humanos , Queratocono/diagnóstico , Curva ROC , Estudios Retrospectivos , Tomografía
12.
Anal Chem ; 93(26): 9174-9182, 2021 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-34155883

RESUMEN

A rapid, on-site, and accurate SARS-CoV-2 detection method is crucial for the prevention and control of the COVID-19 epidemic. However, such an ideal screening technology has not yet been developed for the diagnosis of SARS-CoV-2. Here, we have developed a deep learning-based surface-enhanced Raman spectroscopy technique for the sensitive, rapid, and on-site detection of the SARS-CoV-2 antigen in the throat swabs or sputum from 30 confirmed COVID-19 patients. A Raman database based on the spike protein of SARS-CoV-2 was established from experiments and theoretical calculations. The corresponding biochemical foundation for this method is also discussed. The deep learning model could predict the SARS-CoV-2 antigen with an identification accuracy of 87.7%. These results suggested that this method has great potential for the diagnosis, monitoring, and control of SARS-CoV-2 worldwide.


Asunto(s)
COVID-19 , Aprendizaje Profundo , Humanos , SARS-CoV-2 , Sensibilidad y Especificidad , Espectrometría Raman , Esputo
13.
Phys Chem Chem Phys ; 23(23): 13115-13127, 2021 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-34075970

RESUMEN

The transport and formation of fluorinated compounds are greatly significant due to their possible environmental risks. In this work, the ˙OH-mediated degradation of CF3CF2CF2CH2OH and CF3CHFCF2CH2OH in the presence of O2/NO/NO2 was studied by using density functional theory and the direct kinetic method. The formation mechanisms of perfluorocarboxylic/hydroperfluorocarboxylic acids (PFCAs/H-PFCAs), which were produced from the reactions of α-hydroxyperoxy radicals with NO/NO2 and the ensuing oxidation of α-hydroxyalkoxy radicals, were clarified and discussed. The roles of water and silica particles in the rate constants and ˙OH reaction mechanism with fluoroalcohols were investigated theoretically. The results showed that water and silica particles do not alter the reaction mechanism but obviously change the kinetic properties. Water could retard fluoroalcohol degradation by decreasing the rate constants by 3-5 orders of magnitude. However, the heterogeneous ˙OH-rate coefficients on the silica particle surfaces, including H4SiO4, H6Si2O7, and H12Si6O18, are larger than that of the naked reaction by 1.20-24.50 times. This finding suggested that these heterogeneous reactions may be responsible for the atmospheric loss of fluoroalcohols and the burden of PFCAs. In addition, fluoroalcohols could be exothermically trapped by H12Si6O18, H6Si2O7, and H4SiO4, in which the chemisorption on H12Si6O18 is stronger than that on H6Si2O7 or H4SiO4. The global warming potentials and radiative forcing of CF3CF2CF2CH2OH/CF3CHFCF2CH2OH were calculated to assess their contributions to the greenhouse effect. The toxicities of individual species were also estimated via the ECOSAR program and experimental measurements. This work enhances the understanding of the environmental formation of PFCAs and the transformation of fluoroalcohols.

14.
Chem Eng J ; 410: 128410, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33519294

RESUMEN

Nitrogen doped Mg2TiO4 spinel, i.e. Mg2TiO4-xNy, has been synthesized and investigated as a photocatalyst for antibacterial activity. Mg2TiO4-xNy demonstrates superior photocatalytic activity for E. coli disinfection under visible light illumination (λ ≥ 400 nm). Complete disinfection of E. coli at a bacterial cell density of 1.0 × 107 CFU mL-1 can be achieved within merely 60 min. Mg2TiO4-xNy is capable of generating superoxide radicals (•O2 -) under visible light illumination which are the reactive oxygen species (ROSs) for bacteria disinfection. DFT calculations have verified the importance of nitrogen dopants in improving the visible light sensitivity of Mg2TiO4-xNy. The facile synthesis, low cost, good biocompatibility and high disinfection activity of Mg2TiO4-xNy warrant promising applications in the field of water purification and antibacterial products.

15.
Phys Chem Chem Phys ; 22(15): 8109-8117, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32242551

RESUMEN

Nitrogenous particle participation in the formation of clusters has attracted considerable attention from numerous researchers in recent years. Urea and thiourea (TU), as the common fertilizers in agriculture, have a significant impact on the atmospheric environment, whereas their implications have not been comprehended widely. Herein, we have used quantum calculations and ABCluster to explore the potential roles of thiourea and urea in particle formation events. A vital implication of these results is that they may contribute toward particle formation in marine environments and Asia region where the concentration of thiourea and urea has been increasing for a few years. Furthermore, the mechanisms of NO2 hydrolysis in the presence of thiourea and subsequent reactions were studied deeply. The results indicate that, although these reactions are not thermodynamically favorable at 298.15 K under homogeneous gas-phase conditions, thiourea may promote the hydrolysis of NO2 in heterogeneous environments containing very high concentrations of these molecules. The kinetics analysis shows that the rate constants of the hydrolysis reaction catalyzed by thiourea with N2O4-W and TU-W are about 2-5 and 1-2 orders of magnitude faster than those of the naked reaction. Thiourea nitrate and its aquo-complex were also studied, and the results suggest that the reaction produced an acid-base complex in which the trans- configuration is the final form for nitrous acid. We hope that these findings would inspire field measurements for detecting urea and thiourea in the troposphere.

16.
BMC Ophthalmol ; 20(1): 148, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32295643

RESUMEN

BACKGROUND: Axenfeld-Rieger syndrome (ARS) is a congenital disease with a series of developmental abnormalities, and no case of ARS with cataract and small cornea has been reported in previous studies. In the present report, we aimed to describe the diagnosis and phacoemulsification of an ARS patient with small cornea. CASE PRESENTATION: A 58-year-old Han Chinese male patient who was referred to Eye Center of the Second Affiliated Hospital of Zhejiang University Medical College was diagnosed with ARS. Systemic and ophthalmic examination and genetic testing were performed. The slit-lamp microscopic examination of anterior segment showed obvious nuclear cataract, iris lesions, and the abnormal cornea of both eyes with small transversal and longitudinal diameters. ARS with bilateral complicated cataract and small cornea was diagnosed. Microincision-phacoemulsification in combination with intraocular lens implantation was performed on his left eye. After successful surgery of his left eye, the best-corrected visual acuity (BCVA) was obviously improved from 2 to 0.5 (LogMAR). A transient elevation of intraocular pressure (IOP) was controlled with medication. CONCLUSIONS: Through genetic testing, a known pathogenic mutation NM_153427.2:c.272G > A was detected on the PITX2 gene; and an unknown mutation NM_001453.2:c.1063C > T was detected on FOXC1 gene. For the ARS patient with complicated cataract, the visual acuity was increased by phacoemulsificasion in combination with microincision.


Asunto(s)
Segmento Anterior del Ojo/anomalías , Catarata/diagnóstico , Córnea/anomalías , Anomalías del Ojo/diagnóstico , Enfermedades Hereditarias del Ojo/diagnóstico , Enfermedades Hereditarias del Ojo/genética , Implantación de Lentes Intraoculares , Facoemulsificación , Segmento Anterior del Ojo/diagnóstico por imagen , Segmento Anterior del Ojo/fisiopatología , Anomalías del Ojo/genética , Anomalías del Ojo/fisiopatología , Enfermedades Hereditarias del Ojo/fisiopatología , Factores de Transcripción Forkhead/genética , Pruebas Genéticas , Proteínas de Homeodominio/genética , Humanos , Masculino , Microscopía Acústica , Persona de Mediana Edad , Mutación , Microscopía con Lámpara de Hendidura , Factores de Transcripción/genética , Agudeza Visual/fisiología , Campos Visuales/fisiología , Proteína del Homeodomínio PITX2
17.
Entropy (Basel) ; 22(8)2020 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-33286572

RESUMEN

Due to the nature of the Dempster combination rule, it may produce results contrary to intuition. Therefore, an improved method for conflict evidence fusion is proposed. In this paper, the belief entropy in D-S theory is used to measure the uncertainty in each evidence. First, the initial belief degree is constructed by using an improved base belief function. Then, the information volume of each evidence group is obtained through calculating the belief entropy which can modify the belief degree to get the final evidence that is more reasonable. Using the Dempster combination rule can get the final result after evidence modification, which is helpful to solve the conflict data fusion problems. The rationality and validity of the proposed method are verified by numerical examples and applications of the proposed method in a classification data set.

18.
Phys Chem Chem Phys ; 21(31): 17378-17392, 2019 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-31355843

RESUMEN

The oxidation mechanisms and dynamics of 3-methoxy-3-methyl-1-butanol (3M3M1B) initiated by ˙OH radicals were assessed by the density functional theory and canonical variational transition state theory. The effects of ubiquitous water on the title reactions were analyzed by utilizing an implicit solvation model in the present system. The results suggested that aqueous water played a negative role in the ˙OH-initiated degradation of 3M3M1B with an increase in the Gibbs free barriers. Meanwhile, the barriers were almost independent when explicit water molecules were involved in the gaseous phase, which could reduce the rate constant by approximately 3 orders of magnitude. The kinetic calculations showed that the rate constants were smaller by about 15, 9, 8, and 8 orders of magnitude for hydroxyl-, ammonia-, formic acid-, and sulfur acid-participating reactions, respectively, than that from an unassisted reaction. The results indicated that water, hydroxyl, ammonia, formic acid, or sulfur acid could not facilitate the title reaction when performed in the atmosphere. The investigations of the subsequent oxidation processes of the alkyl radical CH3OC(CH3)2CH2C·HOH indicated that CH3OC(CH3)2CH2CHO was the most favorable product by eliminating an HO2˙ radical. Additionally, the HO2˙ radical could serve as a self-catalyst to affect the above reaction through a double proton transfer process. With the introduction of NO, CH3OC(CH3)2CH2COOH and HNO2 were found to be the main products, which may be regarded as the new source of atmospheric nitrous acid. In the NO2-rich environment, the peroxynitrate of CH3OC(CH3)2CH2CH(OONO2)OH could be formed via the reaction of the CH3OC(CH3)2CH2CH(OO˙)OH radical with NO2. The degradation mechanism of CH3OC(CH3)2CH2CH(OONO2)OH in the presence of water, ammonia, and methylamine was demonstrated, and it was shown that water, ammonia, and methylamine could promote the formation of nitric hydrate and nitrate aerosol. The main species detected in the experiment were confirmed by a theoretical study. The atmospheric lifetimes of 3M3M1B in the temperature range of 217-298 K and altitude of 0-12 km were within the range of 6.83-8.64 h. This study provides insights into the transformation of 3M3M1B in a complex environment.

19.
BMC Ophthalmol ; 19(1): 105, 2019 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-31072310

RESUMEN

BACKGROUND: To present the follow-up outcomes of a modified technique of transscleral suture fixation of posterior chamber intraocular lens (PCIOL) in eyes with inadequate capsule support. METHODS: A retrospective chart review of 21 patients underwent transscleral suture fixation of a foldable 3-looped haptics one-piece PCIOL implantation through scleral pockets was conducted. Preoperative data and follow-up data for at least 3 months were collected for all patients. RESULTS: The mean operative duration was 36.62 ± 10.70 min. The mean pre- and post-operative LogMAR uncorrected distance visual acuity was (1.25 ± 0.50 vs. 0.41 ± 0.22, P < 0.01). The mean pre- and post-operative LogMAR best corrected visual acuity was (0.48 ± 0.25 vs. 0.33 ± 0.24, P < 0.01). The mean proportion of postoperative endothelial cell loss was 11.46 ± 4.78%. The mean postoperative anterior chamber depth was 3.05 ± 0.44 mm. The mean postoperative IOL tilt degree was 2.81 ± 1.41°, and the mean postoperative IOL decentration degree was 0.31 ± 0.13 mm. Four patients with transient corneal edema (19.0%) and three patients with transiently elevated IOP (14.3%) were observed after operation, and such complications were resolved within 1 week. No severe complications were observed. CONCLUSIONS: The modified technique was a feasible method of PCIOL implantation.


Asunto(s)
Implantación de Lentes Intraoculares/métodos , Lentes Intraoculares , Esclerótica/cirugía , Técnicas de Sutura , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tempo Operativo , Estudios Retrospectivos , Agudeza Visual , Adulto Joven
20.
Inorg Chem ; 57(4): 1958-1963, 2018 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-29419290

RESUMEN

Designing new materials with reduced dimensionality and distinguished properties has continuously attracted intense interest for materials innovation. Here we report a novel two-dimensional (2D) Zn2C monolayer nanomaterial with exceptional structure and properties by means of first-principles calculations. This new Zn2C monolayer is composed of quasi-tetrahedral tetracoordinate carbon and quasi-linear bicoordinate zinc, featuring a peculiar zigzag-shaped buckling configuration. The unique coordinate topology endows this natural 2D semiconducting monolayer with strongly strain tunable band gap and unusual negative Poisson ratios. The monolayer has good dynamic and thermal stabilities and is also the lowest-energy structure of 2D space indicated by the particle-swarm optimization (PSO) method, implying its synthetic feasibility. With these intriguing properties the material may find applications in nanoelectronics and micromechanics.

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