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1.
Appl Opt ; 62(28): 7367-7372, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37855504

RESUMO

Non-line-of-sight (NLOS) optical camera communications (OCC) exhibit greater link availability and mobility than line-of-sight links, which are more susceptible to blocking and shadowing. In this work, we propose an NLOS OCC system, where the data signal is mapped into color pulse width modulation (CPWM) symbols prior to transmission using a red-, green-, and blue light-emitting diode. A convolutional-neural-network-based receiver is used to demodulate the CPWM signal. Based on experimental results, the proposed scheme effectively mitigates the effects of diffuse reflection induced intersymbol interference, resulting in an increased data transmission rate to 7.2 kbps over a link span of more than 2 m, which is typical for indoor applications.

2.
Dalton Trans ; 51(30): 11558-11566, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35848404

RESUMO

Six iron(0) tricarbonyl complexes (1a-f) with a η4-1-azadiene moiety were prepared and their performance in the hydroboration of unsaturated organic compounds was investigated. All the complexes exhibit catalytic activity towards hydroboration of ketones, aldehydes and aldimines with pinacolborane (HBpin) as a hydride source to lead to secondary alcohols, primary alcohols, and secondary amines, respectively, after hydrolysis of the hydroboration products. Of the iron(0) tricarbonyl complexes, complex 1e is the most robust one and was employed throughout the catalytic investigation. Its preference towards the three types of substrates is as follows: aldimines > aldehydes ≫ ketones. In total, 24 substrates were examined for the catalytic hydroboration reactivity and generally, isolation yields ranging from 40% to 95% were achieved. Mechanistic investigation suggests that the catalytic hydroboration of the substrates proceeds via intramolecular hydride transfer without going through an Fe-H intermediate. As indicated by 1H NMR spectroscopic monitoring, the substrates and the borane agent bind to the iron centre and the imine N atom, respectively, which facilitates the hydride transfer by activating the B-H bond and polarizing the double bond of the substrates.


Assuntos
Aldeídos , Boranos , Álcoois/química , Aldeídos/química , Boranos/química , Catálise , Cetonas/química
3.
Zhong Yao Cai ; 31(6): 877-9, 2008 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-18998574

RESUMO

OBJECTIVE: To investigate the expression of bcl-2 and bax genes in the liver cancer cell line HepG2 after apoptosis induced by essential oils from Rosmarinus officinalis. METHODS: Essential oils from Rosmarinus officinalis were collected by steam distillation, then its chemical composition was determined by GC-MS. Expression of bcl-2 and bax genes were detected by immunohistochemical method. RESULTS: The liver cancer cell line HepG2 was treated with essential oils from Rosmarinus officinalis at various concentrations for different duration. Expression of bcl-2 gene reduced and expression of bax gene increased in a dose and time dependent manner. CONCLUSION: Essential oils from Rosmarinus officinalis can affect the pattern of bcl-2 and bax genes expressions, and this may increase the apoptosis of liver cancer cell line HepG2.


Assuntos
Apoptose/efeitos dos fármacos , Óleos Voláteis/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Rosmarinus/química , Proteína X Associada a bcl-2/metabolismo , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/patologia , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Folhas de Planta/química , Fatores de Tempo
4.
Am J Reprod Immunol ; 55(2): 106-14, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16433829

RESUMO

PROBLEM: We investigated host immunologic responses to endometriosis by comparing immune cell surface antigens in peripheral blood (PB) and peritoneal fluid (PF) from women with endometriosis with those in PB and PF from other patients. METHOD OF STUDY: Japanese women with endometriosis (n = 56) were compared with controls with other laparoscopic diagnoses (n = 68). PB and PF were collected at the time of laparoscopy for flow cytometry. RESULTS: No significant difference in phenotypic parameters of T cells (CD3, CD4, and CD8), B cells (CD19), natural killer (NK) cells (CD56), or monocytes/macrophages (CD14) was seen between women with and without endometriosis. However, increased killer immunoglobulin-like receptor (CD158a) expression by NK cells and decreased human leukocyte antigen (HLA)-ABC and -DR expression by macrophages, all suggesting decreased functional activation were found in endometriosis. These markers showed significant association with endometriosis by odds ratio, logistic regression, and decision tree analyses. CONCLUSIONS: Increased CD158a(+) NK cells in PB and PF indicated decreased NK cell cytotoxicity in endometriosis, while decreased HLA expression on PF macrophages suggested impaired antigen presentation. Thus, aberrant immune responses by NK cells and macrophages may represent risk factors for endometriosis.


Assuntos
Endometriose/diagnóstico , Antígenos HLA/metabolismo , Leucócitos/metabolismo , Pelve , Receptores Imunológicos/metabolismo , Biomarcadores , Estudos de Casos e Controles , Suscetibilidade a Doenças , Feminino , Humanos , Receptores KIR , Receptores KIR2DL1
5.
Yi Chuan ; 27(2): 262-70, 2005 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-15843357

RESUMO

To help geneticists look up genetics journals more quickly and exactly,this paper developed this search engine of genetics journals. The paper exploited the search engine with genetics journals sources of Medline database in NCBI, indexed and listed 173 names of genetics journals from Medline. Then obtained one search engine concerning genetics journals after making every journal's super linkage. The search engine can search out not only all articles' titles of 173 genetics journals but also some articles' titles of the journals each year quickly, exactly and dynamically. We can further obtain all articles' abstracts and some full texts in PubMed.


Assuntos
Genética , Armazenamento e Recuperação da Informação/métodos , MEDLINE , Armazenamento e Recuperação da Informação/estatística & dados numéricos , PubMed , Ensino/métodos
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