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1.
Sensors (Basel) ; 23(6)2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36991839

RESUMO

To overcome the problems of long production cycle and high cost in the product manufacturing process, a P2P (platform to platform) cloud manufacturing method based on a personalized custom business model has been proposed in this paper by integrating different technologies such as deep learning and additive manufacturing (AM). This paper focuses on the manufacturing process from a photo containing an entity to the production of that entity. Essentially, this is an object-to-object fabrication. Moreover, based on the YOLOv4 algorithm and DVR technology, an object detection extractor and a 3D data generator are constructed, and a case study is carried out for a 3D printing service scenario. The case study selects online sofa photos and real car photos. The recognition rates of sofa and car were 59% and 100%, respectively. Retrograde conversion from 2D data to 3D data takes approximately 60 s. We also carry out personalized transformation design on the generated sofa digital 3D model. The results show that the proposed method has been validated, and three unindividualized models and one individualized design model have been manufactured, and the original shape is basically maintained.

2.
J Org Chem ; 87(5): 2797-2808, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-35076229

RESUMO

A [3+1+1+1] annulation of arylamines, arylaldehydes, and dimethyl sulfoxide (DMSO) to the pyridine structure in quinolines using DMSO as a nonadjacent dual-methine (═CH-) synthon is disclosed. In this annulation, arylamines provide two carbon atoms and one nitrogen atom, arylaldehydes furnish one carbon atom, and DMSO provides two nonadjacent methines (═CH-) to the pyridine ring in quinoline molecules. This annulation provides a simple approach for the synthesis of 3-arylquinolines from readily available substrates in useful yields. On the basis of the control experiments and the literature, a plausible mechanism is proposed.


Assuntos
Dimetil Sulfóxido , Quinolinas , Aminas , Carbono , Piridinas , Quinolinas/química
3.
J Org Chem ; 87(11): 7022-7032, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35583475

RESUMO

The regioselective synthetic approach to higher alkenes from lower alkenes by using sulfoxides as alkyl or aryl reagents in the Fe3+/H2O2 system has been developed. This reaction realized direct alkylation or arylation of alkenes. In this reaction, sulfoxides afforded one Csp3 or Csp2 atom to the C═C bond of alkenes; one new Csp2-Csp3 bond or Csp2-Csp2 bond was formed. Nearly 40 products including di-, tri-, and tetra-substituted products were regioselectively synthesized. Both aliphatic and aromatic alkenes could participate in this reaction. Moreover, not only dimethyl sulfoxide but also three other sulfoxides can be applied to this reaction, including diethyl, dibenzyl, and diphenyl sulfoxide. The mechanism studies showed that this reaction may experience a coupling process via radical addition-elimination and the Fe3+/H2O2 system made the sulfoxides offered one alkyl or aryl radical to the C═C bond of alkenes.

4.
Zhonghua Nan Ke Xue ; 28(5): 422-426, 2022 May.
Artigo em Zh | MEDLINE | ID: mdl-37477481

RESUMO

OBJECTIVE: To explore the risk factors for long-term hematuria after operation in BPH patients. METHODS: We retrospectively analyzed the clinical data on 646 cases of BPH treated by transurethral surgery in Liyang People's Hospital from January 2015 to August 2020. According to the incidence of hematuria at 3 months or longer after surgery, we divided the patients into a hematuria and a non-hematuria group, recorded the related factors, and investigated the independent risk factors for long-term hematuria by univariate and multivariate analyses. RESULTS: Of the 646 BPH patients, 48 were found with and 598 without hematuria after transurethral surgery. Univariate analysis showed that hypertension, diabetes mellitus, residual prostate gland, urinary tract infection, bladder neck contracture, prostate cancer, urethral calculus, urethral stricture, excessive activity and constipation were the influencing factors (P < 0.05), while multivariate logistic regression analysis revealed that hypertension (P < 0.001), diabetes mellitus (P = 0.007), residual prostate gland (P = 0.013), urinary tract infection (P < 0.001), bladder neck contracture (P = 0.032), urethral calculus (P = 0.033) and urethral stricture (P = 0.001) were independent risk factors for long-term hematuria in the BPH patients after surgery. CONCLUSION: Complicated hypertension, diabetes mellitus, residual prostate gland, urinary tract infection, bladder neck contracture, urethral calculus and urethral stricture are independent risk factors for long-term hematuria in BPH patients after transurethral surgery.


Assuntos
Cálculos , Contratura , Diabetes Mellitus , Hipertensão , Hiperplasia Prostática , Ressecção Transuretral da Próstata , Estreitamento Uretral , Infecções Urinárias , Masculino , Humanos , Hiperplasia Prostática/complicações , Hiperplasia Prostática/cirurgia , Estreitamento Uretral/etiologia , Hematúria/epidemiologia , Hematúria/etiologia , Ressecção Transuretral da Próstata/efeitos adversos , Estudos Retrospectivos , Fatores de Risco , Infecções Urinárias/complicações , Contratura/etiologia , Hipertensão/complicações , Cálculos/cirurgia , Resultado do Tratamento
5.
J Org Chem ; 86(21): 15228-15241, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34632772

RESUMO

An unexpected annulation among 2-aminobenzyl alcohols, benzaldehydes, and DMSO to quinolines has been disclosed. For the reported annulation between 2-aminobenzyl alcohols and benzaldehydes, the change of the solvent from toluene to DMSO led to the change of the product from the diheteroatomic cyclic benzoxazines to monoheteroatomic cyclic quinolines. This annulation can be used to synthesize regioselectively different substituted quinolines by the choice of different 2-amino alcohols, aldehydes, and sulfoxides as substrates. Interestingly, introducing substituent groups to the α-position of sulfoxides resulted in the interchange of the positions between benzaldehydes and sulfoxides in the product quinolines. On the basis of the control experiments and literatures, a plausible mechanism for this annulation was proposed.


Assuntos
Benzaldeídos , Quinolinas , Aldeídos , Dimetil Sulfóxido , Solventes
6.
J Org Chem ; 86(19): 13446-13453, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34546730

RESUMO

Two C═C bond participation in annulation to pyridines using N,N-dimethylformamide (DMF) as the N1 and C4 synthons has been carried out. In this reaction, DMF contributed one N atom and one C atom to two disconnected positions of pyridine ring, with no need for an additional nitrogen source. Two C═C bonds in two molecules of substituted styrenes offered four carbon atoms in the presence of iodine and persulfate. With the optimized conditions in hand, both symmetric and unsymmetric diaryl-substituted pyridines were obtained in useful yields. On the basis of relevant literature and a series of control experimental results, a possible mechanism was proposed in this work, which may demonstrate how DMF provides both N1 and C4 sources.

7.
J Org Chem ; 85(5): 3287-3296, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-31944119

RESUMO

The metal-free-catalyzed synthesis of allyl nitriles from Csp2-Csp3 coupling between olefins and azobis was carried out. Key on this work was that the synthesis of allyl nitriles directly using olefin as a starting material was considered to be more efficient and economical than the alkyne, alkynyl carboxylic acid, or cinnamic acid used in previous works. Moreover, in this reaction, iodine served as the sole promoter, azobis served as a cyanation reagent, and N2 was the only nontoxic byproduct that could avoid the utilization of metal catalysts and virulent nitrile reagents and generation of toxic wastes. With an optimum condition in hand, more than 30 examples of desired products including aromatic and aliphatic nitriles have been synthesized in good to excellent yields. Based on control experiments and literature data, a plausible mechanism of cyanation was proposed.

8.
Acta Biochim Biophys Sin (Shanghai) ; 50(5): 465-472, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29648579

RESUMO

Calpain small subunit 1 (Capn4) has been shown to correlate with the metastasis/invasion of clear cell renal cell carcinoma (ccRCC). This study aimed to further elucidate the molecular mechanisms underlying Capn4-mediated ccRCC progression. The mRNA expression levels in ccRCC cells were measured by quantitative real-time PCR. The effects of Capn4 on cell adhesion, invasion, and migration were examined by cell adhesion assay, cell invasion assay, and wound-healing assay, respectively. The protein levels were detected by western blot analysis. The effect of Capn4 on cancer metastasis in vivo was assessed in a nude mice xenograft model. It was found that Capn4 was up-regulated in the ccRCC cells, and Capn4 overexpression suppressed cell adhesion activity and increased cell invasion and migration in 786-O cells, while Capn4 silencing increased cell adhesion activity and impaired the invasion and migration ability of Caki-1 cells. Capn4 overexpression also increased the protein level of cleaved talin in 786-O cells, while Capn4 silencing decreased the protein level of cleaved talin in Caki-1 cells. The focal adhesion kinase (FAK)/AKT/MAPK signaling was activated by Capn4 overexpression in 786-O cells, and was inhibited by Capn4 down-regulation in Caki-1 cells. Capn4 overexpression increased the protein levels of matrix metalloproteinase 2 (MMP-2), vimentin, N-cadherin, and down-regulated E-cadherin in 786-O cells, while Capn4 silencing decreased the protein levels of MMP-2, vimentin, N-cadherin, and up-regulated E-cadherin in Caki-1 cells. Capn4 also promoted cancer metastasis in the in vivo nude mice xenograft model. Our results implicate the functional role of Capn4 in ccRCC invasion and migration, which may contribute to cancer metastasis in ccRCC.


Assuntos
Calpaína/genética , Carcinoma de Células Renais/genética , Proteína-Tirosina Quinases de Adesão Focal/genética , Neoplasias Renais/genética , Transdução de Sinais/genética , Talina/genética , Animais , Calpaína/metabolismo , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Linhagem Celular , Linhagem Celular Tumoral , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Camundongos Nus , Invasividade Neoplásica , Metástase Neoplásica , Talina/metabolismo , Transplante Heterólogo
9.
Mikrochim Acta ; 185(4): 233, 2018 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-29594803

RESUMO

A method is described for the fluorometric determination of hypochlorite. It is making use of molybdenum disulfide quantum dots (MoS2 QDs) as a fluorescent probe. The QDs are prepared by hydrothermal reaction of sodium molybdate with glutathione. They possess diameters typically ranging from 1.4 to 3.8 nm, excellent stability in water, and blue photoluminescence (with excitation/emission peaks located at 315/412 nm and a quantum yield of 3.7%). The fluorescence of the QDs is statically quenched by hypochlorite, and the Stern-Volmer plot is linear. Hypochlorite can be detected in the 5-500 µM concentration range with a 0.5 µM detection limit. The method has been successfully applied to the determination of hypochlorite in spiked samples of tap water, lake water, and commercial disinfectants. Graphical abstract Schematic of a method for the fluorometric determination of hypochlorite using MoS2 quantum dots as a fluorescent probe. It has been applied to hypochlorite assay in spiked samples of tap water, lake water, and commercial disinfectants.

10.
J Org Chem ; 82(6): 2965-2971, 2017 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-28226207

RESUMO

A novel K2S2O8-promoted decarboxylative cross coupling of α,ß-unsaturated carboxylic acids with cyclic ethers was developed under aerobic conditions. The present protocol, which includes C-C and C═O bond formation in one step through addition, oxidation, and decarboxylation processes, leads to the desired ketone products in moderate to excellent yields. In addition, mechanism studies showed that the transformation process undergoes a radical pathway via a direct activation of the α-sp3 C-H bond of oxygen of the cyclic ether.

11.
J Org Chem ; 82(14): 7159-7164, 2017 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-28650632

RESUMO

A direct α-Csp3-H methylenation of arylketones to form C═C bond using dimethyl sulfoxide as one-carbon source is achieved under transition metal-free reaction condition. Various aryl ketone derivatives react readily with DMSO, producing the α,ß-unsaturated carbonyl compounds in yields of 42 to 90%. This method features a transition metal-free reaction condition, wide substrate scope and using DMSO as novel one-carbon source to form C═C bond, thus providing an efficient and expeditious approach to an important class of α,ß-unsaturated carbonyl compounds. Based on the preliminary experiments, a plausible mechanism of this transformation is disclosed.

12.
Br J Nutr ; 117(5): 737-749, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28366183

RESUMO

The effect of fruit and vegetable intake on breast cancer prognosis is controversial. Thus, a meta-analysis was carried out to explore their associations. A comprehensive search was conducted in PubMed, Web of Science, OVID, ProQuest and Chinese databases from inception to April 2016. The summary hazard ratios (HR) and 95 % CI were estimated using a random effects model if substantial heterogeneity existed and using a fixed effects model if not. Subgroup analyses and sensitivity analyses were also performed. In total, twelve studies comprising 41 185 participants were included in the meta-analysis. Comparing the highest with the lowest, the summary HR for all-cause mortality were 1·01 (95 % CI 0·72, 1·42) for fruits and vegetables combined, 0·96 (95 % CI 0·83, 1·12) for total vegetable intake, 0·99 (95 % CI 0·89, 1·11) for cruciferous vegetable intake and 0·88 (95 % CI 0·74, 1·05) for fruit intake; those for breast cancer-specific mortality were 1·05 (95 % CI 0·77, 1·43) for total vegetable intake and 0·94 (95 % CI 0·69, 1·26) for fruit intake; and those for breast cancer recurrence were 0·89 (95 % CI 0·53, 1·50) for total vegetable intake and 0·98 (95 % CI 0·76, 1·26) for cruciferous vegetable intake. This meta-analysis found no significant associations between fruit and vegetable intake and breast cancer prognosis.


Assuntos
Neoplasias da Mama/epidemiologia , Dieta , Frutas , Verduras , Neoplasias da Mama/mortalidade , China , Estudos de Coortes , Feminino , Humanos , Recidiva Local de Neoplasia/epidemiologia , Prognóstico , Estudos Prospectivos
13.
Eur J Nutr ; 56(3): 1329-1337, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26897124

RESUMO

PURPOSE: Choline and betaine are important for DNA methylation and synthesis, and may affect tumor carcinogenesis. To our knowledge, no previous study has examined the association between serum choline and betaine and breast cancer risk. This study aimed to examine whether serum choline and betaine were inversely associated with breast cancer risk among Chinese women. METHODS: This hospital-based case-control study consecutively recruited 510 breast cancer cases and 518 frequency-matched (age and residence) controls, and blood samples were available for 500 cases and 500 controls. Serum choline and betaine were assayed by high-performance liquid chromatography-tandem mass spectrometry. Multiple unconditional logistic regression was used to estimate odds ratios (ORs) and 95 % confidence intervals (CIs). RESULTS: An inverse association with breast cancer risk was observed for serum betaine (fourth vs first quartile adjusted OR 0.68, 95 % CI 0.47-0.97) and for the ratio of serum betaine to choline (fourth vs first quartile adjusted OR 0.70, 95 % CI 0.48-1.00), but not for serum choline (fourth vs first quartile adjusted OR 0.80, 95 % CI 0.56-1.15). Serum betaine was inversely associated with breast cancer risk in subjects with below-median dietary folate intake (fourth vs first quartile adjusted OR 0.48, 95 % CI 0.30-0.77). CONCLUSIONS: This study suggested that serum betaine but not choline was inversely associated with breast cancer risk. This result needed to be further confirmed by the prospective studies.


Assuntos
Betaína/sangue , Neoplasias da Mama/sangue , Colina/sangue , Adulto , Idoso , Neoplasias da Mama/epidemiologia , Estudos de Casos e Controles , China , Dieta , Exercício Físico , Feminino , Ácido Fólico/administração & dosagem , Ácido Fólico/sangue , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Estado Nutricional , Fatores de Risco , Fatores Socioeconômicos
14.
Br J Nutr ; 115(1): 129-37, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26482064

RESUMO

Previous epidemiological studies have revealed the anti-cancer effect of dietary circulating carotenoids. However, the protective role of specific individual circulating carotenoids has not been elucidated. The purpose of this study was to examine whether serum carotenoids, including α-carotene, ß-carotene, ß-cryptoxanthin, lycopene and lutein/zeaxanthin, could lower the risk for breast cancer among Chinese women. A total of 521 women with breast cancer and age-matched controls (5-year interval) were selected from three teaching hospitals in Guangzhou, China. Concentrations of α-carotene, ß-carotene, ß-cryptoxanthin, lycopene and lutein/zeaxanthin were measured using HPLC. Unconditional logistic regression models were used to calculate OR and 95% CI using quartiles defined in the control subjects. Significant inverse associations were observed between serum α-carotene, ß-carotene, lycopene, lutein/zeaxanthin and the risk for breast cancer. The multivariate OR for the highest quartile of serum concentration compared with the lowest quartile were 0·44 (95% CI 0·30, 0·65) for α-carotene, 0·27 (95% CI 0·18, 0·40) for ß-carotene, 0·41 (95% CI 0·28, 0·61) for lycopene and 0·26 (95% CI 0·17, 0·38) for lutein/zeaxanthin. However, no significant association was found between serum ß-cryptoxanthin and the risk for breast cancer. Stratified analysis by menopausal status and oestrogen receptor (ER)/progesterone receptor (PR) showed that serum α-carotene, ß-carotene, lycopene and lutein/zeaxanthin were inversely associated with breast cancer risk among premenopausal women and among all subtypes of ER or PR status. The results suggest a protective role of α-carotene, ß-carotene, lycopene and lutein/zeaxanthin, but not ß-cryptoxanthin, in breast cancer risk.


Assuntos
Antioxidantes/metabolismo , Neoplasias da Mama/prevenção & controle , Carotenoides/sangue , Adulto , Estudos de Casos e Controles , China , Feminino , Humanos , Pessoa de Meia-Idade , Risco
15.
Br J Nutr ; 116(6): 961-8, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27488260

RESUMO

Choline and betaine are essential nutrients involved in one-carbon metabolism and have been hypothesised to affect breast cancer risk. Functional polymorphisms in genes encoding choline-related one-carbon metabolism enzymes, including phosphatidylethanolamine N-methyltransferase (PEMT), choline dehydrogenase (CHDH) and betaine-homocysteine methyltransferase (BHMT), have important roles in choline metabolism and may thus interact with dietary choline and betaine intake to modify breast cancer risk. This study aimed to investigate the interactive effect of polymorphisms in PEMT, BHMT and CHDH genes with choline/betaine intake on breast cancer risk among Chinese women. This hospital-based case-control study consecutively recruited 570 cases with histologically confirmed breast cancer and 576 age-matched (5-year interval) controls. Choline and betaine intakes were assessed by a validated FFQ, and genotyping was conducted for PEMT rs7946, CHDH rs9001 and BHMT rs3733890. OR and 95 % CI were estimated using unconditional logistic regression. Compared with the highest quartile of choline intake, the lowest intake quartile showed a significant increased risk of breast cancer. The SNP PEMT rs7946, CHDH rs9001 and BHMT rs3733890 had no overall association with breast cancer, but a significant risk reduction was observed among postmenopausal women with AA genotype of BHMT rs3733890 (OR 0·49; 95 % CI 0·25, 0·98). Significant interactions were observed between choline intake and SNP PEMT rs7946 (P interaction=0·029) and BHMT rs3733890 (P interaction=0·006) in relation to breast cancer risk. Our results suggest that SNP PEMT rs7946 and BHMT rs3733890 may interact with choline intake on breast cancer risk.


Assuntos
Betaína/administração & dosagem , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/etiologia , Colina/administração & dosagem , Dieta , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Betaína/metabolismo , Estudos de Casos e Controles , China/epidemiologia , Colina/metabolismo , Feminino , Análise de Alimentos , Regulação da Expressão Gênica , Genótipo , Humanos , Pessoa de Meia-Idade , Fatores de Risco
16.
Br J Nutr ; 113(7): 1129-38, 2015 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-25772260

RESUMO

The colour of the edible portion of vegetables and fruit reflects the presence of specific micronutrients and phytochemicals. No existing studies have examined the relationship between the intake of vegetable and fruit colour groups and the risk of colorectal cancer. The present study, therefore, aimed to investigate these associations in a Chinese population. A case-control study was conducted between July 2010 and July 2014 in Guangzhou, China, in which 1057 consecutively recruited cases of colorectal cancer were frequency-matched to 1057 controls by age (5-year interval), sex and residence (rural/urban). A validated FFQ was used to collect dietary information during face-to-face interviews. Vegetables and fruit were classified into four groups according to the colour of their primarily edible parts: green; orange/yellow; red/purple; white. Unconditional logistic regression models were used to estimate the OR and 95 % CI. A higher consumption of orange/yellow, red/purple and white vegetables and fruit was inversely associated with the risk of colorectal cancer, with adjusted OR of 0·16 (95 % CI 0·12, 0·22) for orange/yellow, 0·23 (95 % CI 0·17, 0·31) for red/purple and 0·53 (95 % CI 0·40, 0·70) for white vegetables and fruit when the highest and lowest quartiles were compared. Total vegetable intake and total fruit intake have also been found to be inversely associated with colorectal cancer risk. However, the intake of green vegetable and fruit was not associated with colorectal cancer risk. The results of the present study, therefore, suggest that a greater intake of orange/yellow, red/purple and white vegetables and fruit is inversely associated with the risk of colorectal cancer.


Assuntos
Neoplasias Colorretais/prevenção & controle , Dieta , Frutas/metabolismo , Pigmentos Biológicos/biossíntese , Verduras/metabolismo , Adulto , Idoso , Institutos de Câncer , Estudos de Casos e Controles , China/epidemiologia , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/etiologia , Dieta/efeitos adversos , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Saúde da População Rural , Caracteres Sexuais , Inquéritos e Questionários , Saúde da População Urbana
17.
Eur J Nutr ; 54(4): 619-28, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25049110

RESUMO

PURPOSE: The associations between specific carotenoid intake and colorectal cancer risk remain inconsistent. The aim of this study was to examine the association between specific dietary carotenoid intake with colorectal cancer risk in Chinese adults. METHOD: From July 2010 to October 2013, 845 eligible colorectal cancer cases and 845 frequency-matched controls (age and sex) completed in-person interviews. A validated food frequency questionnaire was used to estimate dietary intake. Multivariate logistical regression models were used to calculate the odds ratio (OR) and 95% confidence intervals (95% CIs) of colorectal cancer risk after adjusting for various confounders. RESULTS: A strong inverse association was found between ß-cryptoxanthin intake and colorectal cancer risk. Compared with the lowest quartile, the highest quartile intake showed a risk reduction of 77% (OR 0.23, 95% CI 0.17-0.33, P trend < 0.01) after adjustment for various confounding variables. The inverse associations were also observed for α-carotene (OR 0.50, 95% CI 0.37-0.68, P trend < 0.01), ß-carotene (OR 0.67, 95% CI 0.49-0.91, P trend < 0.01), and lycopene (OR 0.51, 95% CI 0.37-0.70, P trend < 0.01). There was no statistically significant association between lutein/zeaxanthin intake and colorectal cancer risk. These findings were consistent across cancer site, sources of controls, and smoking status. The inverse associations between dietary α-carotene, ß-cryptoxanthin, and lycopene intake and colorectal cancer risk were found in both males and females, while inverse associations between ß-carotene intake and colorectal cancer risk were only observed in males. CONCLUSIONS: Consumption of α-carotene, ß-carotene, ß-cryptoxanthin, and lycopene was inversely associated with colorectal cancer risk. No significant association was found between lutein/zeaxanthin intake and colorectal cancer risk.


Assuntos
Povo Asiático , Carotenoides/administração & dosagem , Neoplasias Colorretais/epidemiologia , Criptoxantinas/administração & dosagem , beta Caroteno/administração & dosagem , Adulto , Idoso , Estudos de Casos e Controles , China , Dieta , Feminino , Humanos , Estilo de Vida , Modelos Logísticos , Luteína/administração & dosagem , Licopeno , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores de Risco , Fatores Socioeconômicos , Inquéritos e Questionários , Zeaxantinas/administração & dosagem
18.
J Org Chem ; 78(11): 5691-3, 2013 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-23679103

RESUMO

Oxidative rearrangement of internal alkynes catalyzed by manganese(III) porphyrin is described, which opens a new access to one-carbon-shorter ketones using molecular oxygen. Under the standard conditions, a variety of alkynes including diarylalkynes and arylalkylalkynes rearranged smoothly to the corresponding ketones in high yields. Based upon experimental observations, a plausible reaction mechanism is proposed.


Assuntos
Alcinos/química , Carbono/química , Cetonas/síntese química , Manganês/química , Metaloporfirinas/química , Catálise , Cetonas/química , Estrutura Molecular , Oxirredução
19.
Sci Rep ; 13(1): 7660, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37169857

RESUMO

The high content of organic matter in sludge is the primary reason for the poor solidifying effect and excessive dosage of the cement base. In this study, potassium ferrate and straw fiber are utilized to synergistically enhance the solidifying effect of the cement and elaborate the strength mechanisms. Among them, potassium ferrate was selected to oxidize and crack the structure of organic matter in sludge and consume part of organic matter; straw fiber was used as an adsorption material to absorb some of the organic material and reduce its interference with the cement hydration reaction; the skeleton function of straw fiber in solidified sludge was used to improve the final solidified sludge strength. It is shown that the presence of these two additives significantly improved the cement solidification strength and reduced the moisture content of the solidified body. Moreover, the moisture content and strength followed an obvious linear relationship (adjusted R2 = 0.92), with the strength increasing as the moisture content decreased. After pretreatment with potassium ferrate, the free water content in the dewatered sludge increased by 4.5%, which was conducive to the adequate hydration reaction with cement. The analysis using X-ray diffraction (XRD), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS), and mercury intrusion porosimetry (MIP) revealed potassium ferrate synergizes with straw fibers to promote the production of hemihydrate gypsum and gismondine. However, hemihydrate gypsum, calcium carbonate, and gismondine resulted in structural swelling, which was confirmed by the microscopic morphology and pore structure analysis. However, the adverse effects due to swelling were offset by the increase in strength brought by the above crystalline substances.

20.
Rev Sci Instrum ; 93(9): 093102, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36182477

RESUMO

Space-ground laser time transfer is of significant importance to effectively function a high-precision time synchronization system. Instead of the single-pixel single-photon avalanche detector (SPAD) commonly used in the laser time transfer system, the SPAD array device is capable of supporting the greater performance of the signal photon capture. In this paper, it is experimentally demonstrated that the detection precision and time deviation (TDEV) of the SPAD array can be extremely improved by an order of magnitude compared with those of a single-pixel SPAD. As a result, 2.4 ps root mean square precision and 0.25 ps over an averaging time of 1000 s TDEV are achieved for the SPAD array, providing a new detection method for high-precision laser time transfer applications, such as space-ground optical clocks.

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