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1.
Org Lett ; 25(1): 163-168, 2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-36566387

RESUMO

Herein we report the first catalytic decarbonylation and decarbonylative hydroamination of formamides without using additives enabled by a redox-neutral rare earth catalyst. The protocol displays complete N-aryl/alkenyl formamide-selectivity, thus providing a wide variety of creative uses of the N-formylation and N-deformylation method and opening up new prospects for minimizing waste and controlling the required selectivity in amine transformation events.


Assuntos
Aminas , Formamidas , Catálise
2.
ACS Omega ; 7(32): 28284-28292, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35990445

RESUMO

Hierarchical porous heteroatom-doped carbon composites were developed by carbonization followed by KOH activation process, with natural silkworm cocoon and chemical exfoliated graphene sheets as starting materials. The introduction of graphene sheets offers more hierarchical micro/meso porosities, a low charge-transfer resistance, and a large BET surface area of ∼1281.8 m2 g-1, which are responsible for the fast charge/discharge kinetics and the high rate capability compared with those of single silk fibroins-derived carbon materials. The silk fiber provides a high level of heteroatom functionalities (∼2.54% N and ∼21.3% O), which are desirable for high faradaic pseudocapacitance. The as-prepared carbon composite exhibited a high specific capacitance of 290 F g-1 with good rate capability and cycling stability. The symmetric supercapacitors yielded a high value of energy density of 12.9 W h kg-1 at a power density of 95 W kg-1 with a 1.45 V voltage range in 1 M KOH aqueous electrolytes.

3.
Front Oncol ; 12: 755936, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35372055

RESUMO

Background: Clear cell renal cell carcinoma (ccRCC) remains a common malignancy in the urinary system. Although dramatic progress was made in multimodal therapies, the improvement of its prognosis continues to be unsatisfactory. The antibody-binding crystallizable fragment (Fc) γ receptors (FcγRs) are expressed on the surface of leukocytes, to mediate antibody-induced cell-mediated anti-tumor responses when tumor-reactive antibodies are present. FcγRs have been studied extensively in immune cells, but rarely in cancer cells. Methods: ONCOMINE, UALCAN, GEPIA, TIMER, TISIDB, Kaplan-Meier Plotter, SurvivalMeth, and STRING databases were utilized in this study. Results: Transcriptional levels of FcγRs were upregulated in patients with ccRCC. There was a noticeable correlation between the over expressions of FCGR1A/B/C, FCGR2A, and clinical cancer stages/tumor grade in ccRCC patients. Besides, higher transcription levels of FcγRs were found to be associated with poor overall survival (OS) in ccRCC patients. Further, high DNA methylation levels of FcγRs were also observed in ccRCC patients, and higher DNA methylation levels of FcγRs were associated with shorter OS. Moreover, we also found that the expression of FcγRs was significantly correlated with immune infiltrates, namely, immune cells (NK, macrophages, Treg, cells) and immunoinhibitor (IL-10, TGFB1, and CTLA-4). Conclusions: Our study demonstrated that high DNA methylation levels of FcγRs lead to their low mRNA, protein levels, and poor prognosis in ccRCC patients, which may provide new insights into the choice of immunotherapy targets and prognostic biomarkers.

4.
ACS Omega ; 6(42): 27814-27822, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34722981

RESUMO

Nowadays, boron nitride (BN) has attracted a great deal of attention due to its physical and chemical properties, such as high-temperature resistance, oxidation resistance, heat conduction, electrical insulation, and neutron absorption. The unique lamellar, reticular, and tubular morphologies and physicochemical properties of BN make it attractive in the fields of adsorption, catalysis, hydrogen storage, thermal conduction, insulation, dielectric substrate of electronic devices, radiation protection, polymer composites, medicine, etc. Based on this, we propose a novel method to produce boron nitride nanosheets (BNNSs) by a two-step method. The structure and morphology of the prepared BNNSs were characterized by scanning electron microscopy, transmission electron microscopy, atomic force microscopy, XRD, FTIR, etc. The results showed that the prepared BNNSs had high crystallinity and the stripping efficiency of h-BN as well as the performance and yield of BNNSs had been improved, and the cost and environmental pollution of BNNS preparation had been reduced accordingly.

5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(3): 616-9, 2009 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-19455785

RESUMO

The traditional method of measuring the aeroengine exhausts is intrusive gas sampling analysis techniques. The disadvantages of the techniques include complex system, difficult operation, high costs and potential danger because of back-pressure effects. The non-intrusive methods have the potential to overcome these problems. So the remote FTIR passive sensing is applied to monitor aeroengine exhausts and determine the concentration of the exhausts gases of aeroengines. The principle of FTIR remote passive sensing is discussed. The model algorithm for the calibration of FTIR system, the radiance power distribution and gas concentration are introduced. TENSOR27 FTIR-system was used to measure the spectra of infrared radiation emitted by the hot gases of exhausts in a test rig. The emission spectra of exhausts were obtained under different thrusts. By analyzing the spectra, the concentrations of CO2, CO and NO concentration were calculated under 4 thrusts. Researches on the determination of concentration of the exhausts gases of aeroengines by using the remote FTIR sensing are still in early stage in the domestic aeronautics field. The results of the spectra and concentration in the aeroengine test are published for the first time. It is shown that the remote FTIR passive sensing techniques have a great future in monitoring the hot gas of the aeroengines exhausts.

6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(10): 2304-7, 2008 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-19123394

RESUMO

Since the composition and concentration of aeroengine exhaust can reflect the combustion efficiency, they can provide the basis for condition based maintenance, and also the basis for the analysis of environment pollution caused by aeroengine exhaust. So the importance of aeroengine exhaust detection is evident. Up to now, the measurement of aeroengine exhaust is based on sampling analysis which is not convenient and can't meet the detection requirements when an aeroplane is flying-off or flying in the sky. Hence, new methods of exhaust detection must be studied. The passive measurement technology based on Fourier transform infrared spectroscopy (FTIR) was applied to the measurement of aeroengine exhaust in the present paper. At first, the principle of passive measurement based on FTIR was introduced in detail. On this basis, a model algorithm for gas concentration calculation was deduced based on the principle of infrared transmission. Then the feasibility of aeroengine exhaust measurement based on passive FTIR was analyzed, and the passive measurement method of aeroengine exhaust based on FTIR was given. In the end, an experiment of aeroengine exhaust passive measurement was carried out by a FTIR with the type of Tensor 27 produced by BRUKER. Good quality spectra of the exhaust and the background were measured. Based on the model algo rithm of passive measurement, the absorbance spectra of CO and NO were obtained respectively, and the concentrations of CO and NO were figured out. To check up the veracity of this method, a comparison was made with another apparatus. There were only little differences between the results of the two experiments, showing that the passive measurement technology based on FTIR could meet the requirements of aeroengine exhaust detection.

7.
Artigo em Chinês | MEDLINE | ID: mdl-16200966

RESUMO

OBJECTIVE: To test and evaluate the olfactory function of patient after total laryngectomy, seek to a practical method to ameliorate olfactory function and rise the qualitative character of these patients. METHODS: Using the T&T olfactory examination to evaluate the olfactory function of 60 cases. Four cases olfactory mucosae were observed by electron microscope. Observing relation among the remains olfaction, the time after operation and whether or not undergone the voice reconstruction. And analyse the reasons of the above hyposomnia. Using the closing-mouth and nasal out-word airflow maneuver (CNOAM) as the intervention in the patients of tracheoesophageal fistula voice reconstruction after total laryngectomy to observe the amelioration after intervention. RESULTS: It shows various degree of hyposmia and anosmia in the cases after total laryngectomy with or without tracheoesophageal fistula voice reconstruction, with significant deference (P < 0.01) compared to the normal person respectively. There are precisely correlation among the time after operation and whether or not undergone the voice reconstruction. The longer time leads to less remaining olfaction. The patients after total laryngectomy without tracheoesophageal fistula voice reconstruction have lost their olfaction thoroughly within 5 years. But for the patients after total laryngectomy with tracheoesophageal fistula voice reconstruction, they have a middle hyposmia within 5 years, with significant deference (P < 0.01) between the patients in 5 years and after 5 years. There were significant differences (P < 0.01) between the values of patients with and without tracheoesophageal fistula voice reconstruction. The ultrastructure of 4 cases of olfactory epithelium shows the apoptosis change. After the treatment of CNOAM, the remaining olfaction of most patients were improved, with significant deference (P < 0.01) compared to those before the treatment of CNOAM. CONCLUSIONS: The proceed hypofunction of olfaction may be influenced by the reform of respiratory air, the extinction of air velocity bypass the nasal cavity and the apoptosis of epithelial cells in the patients after total laryngectomy. But if we give an early intervention study such as tracheoesophageal fistula voice reconstruction and CNOAM, the olfactory function may be maintenance. During the intervention, the ending of olfactory nerves may be get uninterrupt stimulation. This may help the patients keep a better existing quality than those fail to accept the interventions.


Assuntos
Laringectomia/efeitos adversos , Nervo Olfatório/fisiopatologia , Olfato , Adulto , Idoso , Carcinoma de Células Escamosas/fisiopatologia , Estudos de Casos e Controles , Feminino , Humanos , Neoplasias Laríngeas/fisiopatologia , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório
8.
Lin Chuang Er Bi Yan Hou Ke Za Zhi ; 18(6): 336-8, 2004 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-15354773

RESUMO

OBJECTIVE: To observe the mechanism of the rehabilitated speech using slit-like fistula between trachea and esophagus after total laryngectomy. METHOD: Forty patients after total laryngectomy all come from the fourth central hospital of Tianjin. They all reconstructed voice using slit-like fistula between trachea and esophagus primary or secondary stage. We use teleradiography and laryngotroboscope to observe its mechanism of store gas stage, deliver gas stage and phonation stage. RESULT: While inspiratory, the pulmonary enlarged, and the upper esophagus was closed and circulus invension. After this, the infra-pharyngeal cavity expanded, looks like a downward triangular taper. The upper end of the esophagus opened suddenly. Phonation begin, the superior esophagus was full of air as a ball. The air escape through the segment of trachea-esophagus. The meatus of esophagus opened in coronal position and turn over like lip. It is vibrated together with nearby mucus, mucosa to form voice. After that, thorax shrink, the meatus of esophagus turn in again, the voice behavior is over. CONCLUSION: The power organ of trachea-esophagus voice is lung. It is crucial for the trachea-esophagus fistula unobstructed and smooth to forming voice. When phonation, the mucosa, mucus of infra-pharyngeal and esophageal meatus take part in vibration.


Assuntos
Esôfago/fisiopatologia , Laringectomia , Voz Alaríngea , Traqueia/fisiopatologia , Idoso , Esôfago/cirurgia , Feminino , Humanos , Neoplasias Laríngeas/reabilitação , Neoplasias Laríngeas/cirurgia , Laringectomia/métodos , Masculino , Pessoa de Meia-Idade , Traqueia/cirurgia
9.
Zhonghua Er Bi Yan Hou Ke Za Zhi ; 38(3): 225-8, 2003 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-14515786

RESUMO

OBJECTIVE: To evaluate the quality of voice restored by using a tracheoesophageal slit-like fistula objectively through acoustic analysis. METHODS: Seven objective voice parameters (fundamental frequency, intensity, duration, formant F1, F2, F3 and their energy, jitter, and shimmer) of esophageal speech, Blom-Singer prosthesis voice, tracheoesophageal slit-like fistula voice, primary or modified surgical restored, and normal voice were analyzed and compared. RESULTS: T test was used for statistical analysis. The maximum phonation time of slit-like fistula voice was shorter than that of normal voice, longer than that of esophageal voice, no significant difference compared with that of Blom-Singer prosthesis voice. Its sound intensity of it was similar to that of normal voice and Blom-Singer voice, better than that of esophageal voice. Its fundamental frequency was lower than that of normal voice. Its shimmer and jitter was more than that of normal voice, less than that of esophageal voice, and similar to that of Blom-singer one. Compared with esophageal voice, all formants but F1 of it were not statistically different. No statistical difference between the 2 groups of slit-like fistula patients, i.e., the instant slit-like fistula construction after total laryngectomy and the second stage slit-like fistula construction. CONCLUSION: The voice quality of the patients with tracheoesophageal slit-like fistula is similar to that of the normal and could meet the needs of daily life.


Assuntos
Laringe Artificial , Fístula Traqueoesofágica/reabilitação , Fístula Traqueoesofágica/cirurgia , Qualidade da Voz , Adulto , Idoso , Feminino , Humanos , Laringectomia , Masculino , Pessoa de Meia-Idade , Voz Esofágica
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