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1.
J Am Chem Soc ; 135(28): 10214-7, 2013 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-23829317

RESUMO

A polar homochiral 3D MOF [{Co2(L)(bpe)(H2O)}·5H2O]n constructed with cobalt(II) and a new ligand N-(1,3-dicarboxy-5-benzyl)-carboxymethylglycine (H4L) accommodates ordered helical water streams in its helical grooves. It provides the first example of switchable ferroelectric and optical behavior through two-step reversible single-crystal to single-crystal transformation (SCSC) upon desorption/adsorption of water spirals and coordinated water molecules, respectively.


Assuntos
Compostos Organometálicos/química , Água/química , Adsorção , Cobalto/química , Modelos Moleculares , Teoria Quântica , Propriedades de Superfície
2.
Opt Express ; 21(13): 15522-9, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23842339

RESUMO

We report on the fabrication of stress-induced optical channel waveguides and waveguide splitters with laser-depressed cladding by femtosecond laser. The laser beam was focused into neodymium doped phosphate glass by an objective producing a destructive filament. By moving the sample along an enclosed routine in the horizontal plane followed by a minor descent less than the filament length in the vertical direction, a cylinder with rarified periphery and densified center region was fabricated. Lining up the segments in partially overlapping sequence enabled waveguiding therein. The refractive-index contrast, near- and far-field mode distribution and confocal microscope fluorescence image of the waveguide were obtained. 1-to-2, 1-to-3 and 1-to-4 splitters were also machined with adjustable splitting ratio. Compared with traditional femtosecond laser writing methods, waveguides prepared by this approach showed controllable mode conduction, strong field confinement, large numerical aperture, low propagation loss and intact core region.

3.
Ann Med ; 55(1): 2231342, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37395196

RESUMO

PURPOSE: Due to the poor and unpredictable prognosis of breast cancer (BC) patients with bone metastasis, it is necessary to find convenient and available prognostic predictors. This study aimed to recognize the clinical and prognostic factors related to clinical laboratory examination and to construct a prognostic nomogram for BC bone metastasis. METHODS: We retrospectively analyzed 32 candidate indicators from clinical features and laboratory examination data of 276 BC patients with bone metastasis. Univariate and multivariate regression analyses were performed to identify significant prognostic factors related to BC with bone metastasis. Nomogram was constructed and estimated by receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis. RESULTS: Patients were randomly grouped into training (n = 197) and validation cohorts (n = 79). In training cohort, the multivariate regression analysis revealed that age, other organ metastasis sites, serum level of lactate dehydrogenase, globulin, white blood cell count, mean corpuscular volume, mean corpuscular hemoglobin, and monocyte ratio were independent prognostic factors for BC with bone metastasis. The prognostic nomogram in training cohort exhibited areas under the ROC curve (AUCs) of 0.797, 0.782, and 0.794, respectively, for predicting 1-, 3-, and 5-year overall survival. In validation cohort, the nomogram still showed acceptable discrimination ability (AUCs: 0.723, 0.742, and 0.704) and calibration. CONCLUSION: This study constructed a novel prognostic nomogram for BC patients with bone metastasis. It could serve as a potential tool of survival assessment to help individual treatment decision-making for clinicians.


Our study investigated potential prognostic value of indicators from biochemical and blood routine examination for breast cancer patients with bone metastasis.Our study established a nomogram based on the indicators from biochemical and blood routine examination, which might enhance the ability to predict prognosis of breast cancer patients with bone metastasis.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Neoplasias da Mama/diagnóstico , Índices de Eritrócitos , Testes Hematológicos , Prognóstico , Estudos Retrospectivos
4.
Opt Express ; 20(6): 6712-9, 2012 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-22418555

RESUMO

We report on the formation and the optical properties of the planar and ridge optical waveguides in rutile TiO2 crystal by He+ ion implantation combined with micro-fabrication technologies. Planar optical waveguides in TiO2 are fabricated by high-energy (2.8 MeV) He+-ion implantation with a dose of 3 × 10¹6 ions/cm² and triple low energies (450, 500, 550) keV He+-ion implantation with all fluences of 2 × 10¹6 ions/cm² at room temperature. The guided modes were measured by a modal 2010 prism coupler at wavelength of 1539 nm. There are damage profiles in ion-implanted waveguides by Rutherford backscattering (RBS)/channeling measurements. The refractive-index profile of the 2.8 MeV He+-implanted waveguide was analyzed based on RCM (Reflected Calculation Method). Also ridge waveguides were fabricated by femtosecond laser ablation on 2.8 MeV ion implanted planar waveguide and Ar ion beam etching on the basis of triple keV ion implanted planar waveguide, separately. The loss of the ridge waveguide was estimated. The measured near-field intensity distributions of the planar and ridge modes are all shown.


Assuntos
Íons Pesados , Refratometria/instrumentação , Ressonância de Plasmônio de Superfície/instrumentação , Titânio/química , Titânio/efeitos da radiação , Desenho de Equipamento , Análise de Falha de Equipamento , Hélio , Íons
5.
Huan Jing Ke Xue ; 41(12): 5562-5570, 2020 Dec 08.
Artigo em Zh | MEDLINE | ID: mdl-33374073

RESUMO

Classifying the quality of agricultural products is an important means of managing the arable land quality and guaranteeing the quality and safety of agricultural products. This work is planned to be completed in 2020. However, there is still no perfect method or technology for classifying the quality of arable lands. The species sensitivity distribution (SSD) has become commonly used for determining ecological safety thresholds since it takes into account differences in species sensitivity, the physical and chemical properties of soils, biological availability, and sources of pollutants. However, it has not yet been applied to the classification of arable land quality. Therefore, based on the routine monitoring data of rice production areas in southern China from the Agro-environmental Monitoring Center of China, this study proposes the use of species sensitivity distributions to classify the environmental quality of cadmium in rice production areas. The scientific rationale of this method was also discussed in order to provide an important reference for the construction and improvement of the classification system for arable land quality in China. The results showed that the pH, soil organic matter, and cation exchange capacity of the physical and chemical properties of soils significantly affected the enrichment of cadmium in rice, and this relationship was used to establish the cadmium transfer equation in the soil-rice system. It was found that there were obvious differences in the cadmium enrichment abilities of different rice varieties, which were mainly caused by the differences in their genotypes. According to the species sensitivity distributions, soil cadmium thresholds were obtained, which yielded a priority protection class of less than 0.26 mg·kg-1 and strict control class of greater than 1.67 mg·kg-1, between which are the safe use classes. The results were verified through independent datasets, and it was found that the application of species sensitivity distributions to classify the environmental quality of cadmium in rice producing areas reflected good scientific rationale and operability. This study may provide a foundation for the construction and improvement of the arable land quality classification system in China.

6.
Sci Rep ; 5: 13768, 2015 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-26347949

RESUMO

Cellulosome is a kind of multienzyme complex that displays high activity, selectivity, and stability. Here, we report a novel, non-cellulolytic, cellulosome-like multienzyme complex that produced by the Cellulosimicrobium cellulans wild-type strain F16 isolated from soil microflora. This multienzyme complex, with excellent catalytic efficiency of kcat 13.2 s(-1) to remove the C-7 xylosyl group from 7-xylosyl-10-deacetylpaclitaxel (10-DAXP), has an outstanding tolerance against organic solvents and an excellent general stability, with the long half-life of 214 hours. This cellulosome-like multienzyme complex has a novel structure distinct from the well-documented ones. The key catalytic subunit responsible for the ß-xylosidase activity against 10-DAXP is identified to be a novel protein, indicating a new glycoside hydrolase (GH) family. The pioneering work described here offers a novel nanoscale biocatalyst for the production of biofuels and chemicals from renewable plant-based natural resources.


Assuntos
Celulossomas/metabolismo , Complexos Multienzimáticos/química , Complexos Multienzimáticos/metabolismo , Sequência de Aminoácidos , Catálise , Ativação Enzimática , Estabilidade Enzimática , Genoma Bacteriano , Genômica , Glicosídeos/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Hidrólise , Cinética , Dados de Sequência Molecular , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/isolamento & purificação , Paclitaxel/análogos & derivados , Paclitaxel/metabolismo , Estrutura Secundária de Proteína , Subunidades Proteicas , Alinhamento de Sequência , Relação Estrutura-Atividade , Especificidade por Substrato
7.
Artigo em Inglês | MEDLINE | ID: mdl-22245883

RESUMO

The reaction of AgNO3, pyrazine (pyz) and 1,2,3-benzenetricarboxylic acid (H3btc) leads to a new 3D supramolecular architecture, namely {[Ag(H2btc)(pyz)]·(H2O)2}n (1), which has been characterized by IR spectroscopy, elemental analysis, thermogravimetry, photoluminescent and powder X-ray diffraction (PXRD). Compound 1 displays a 3D supramolecular network, which is built from cationic Ag-pyz chains and anionic [(H2btc)n·2H2O]- layers through the weak Ag⋯O interaction. Complex 1 exhibits photoluminesscence with an emission maximum at ca.391 nm upon excitation at ca. 241 nm.


Assuntos
Benzeno/química , Prata/química , Ácidos Tricarboxílicos/química , Benzeno/síntese química , Cristalografia por Raios X , Ligação de Hidrogênio , Luminescência , Modelos Moleculares , Conformação Molecular , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Ácidos Tricarboxílicos/síntese química
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