Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
1.
Environ Manage ; 53(6): 1119-31, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24696038

RESUMO

Environmental dredging is an efficient means to counteract the eutrophication of water bodies caused by endogenous release of nitrogen and/or phosphorus from polluted sediments. The huge operational cost and subsequent disposal cost of the dredged polluted sediments, as well as the adverse effect on the benthic environment caused by excessive dredging, make the currently adopted dredging methods unfavorable. Precise dredging, i.e., determining the dredging depth based on the pollution level, not only significantly decreases the costs but also leaves a uniform favorable environment for benthos. However, there is still no feasible process to make this promising method executable. Taking a river heavily polluted by organic compounds as an example, we proposed an executable precise dredging process, including sediment survey, model establishment, data interpolation, and calculation of dredging amount. Compared with the traditional dredging method, the precise one would save 16 to 45% of cost according to different pollutant removal demands. This precise dredging method was adopted by the National Water Project of China to treat the endogenous pollution of Nanfei River in 2010. This research provides a universal scientific and engineering basis for sediment dredging projects.


Assuntos
Engenharia/métodos , Eutrofização , Sedimentos Geológicos , Modelos Econômicos , Rios , China , Monitoramento Ambiental , Nitrogênio/análise , Compostos Orgânicos , Fósforo/análise , Poluição da Água
2.
J Natl Cancer Inst ; 115(6): 742-748, 2023 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35094066

RESUMO

BACKGROUND: Adding radiotherapy (RT) to systemic therapy improves progression-free survival (PFS) and overall survival (OS) in oligometastatic non-small cell lung cancer (NSCLC). Whether these findings translate to epidermal growth factor receptor (EGFR)-mutated NSCLC remains unknown. The SINDAS trial (NCT02893332) evaluated first-line tyrosine kinase inhibitor (TKI) therapy for EGFR-mutated synchronous oligometastatic NSCLC and randomized to upfront RT vs no RT; we now report the prespecified interim analysis at 68% accrual. METHODS: Inclusion criteria were biopsy-proven EGFR-mutated adenocarcinoma (per amplification refractory mutation system or next generation sequencing), with synchronous (newly diagnosed, treatment naïve) oligometastatic (≤5 metastases; ≤2 lesions in any one organ) NSCLC without brain metastases. All patients received a first-generation TKI (gefitinib, erlotinib, or icotinib), and randomization was between no RT vs RT (25-40 Gy in 5 fractions depending on tumor size and location) to all metastases and the primary tumor/involved regional lymphatics. The primary endpoint (intention to treat) was PFS. Secondary endpoints included OS and toxicities. All statistical tests were 2-sided. RESULTS: A total of 133 patients (n = 65 TKI only, n = 68 TKI with RT) were enrolled (2016-2019). The median follow-up was 23.6 months. The respective median PFS was 12.5 months vs 20.2 months (P < .001), and the median OS was 17.4 months vs 25.5 months (P < .001) for TKI only vs TKI with RT. Treatment yielded no grade 5 events and a 6% rate of symptomatic grade 3-4 pneumonitis in the TKI with RT arm. Based on the efficacy results of this prespecified interim analysis, the ethics committee recommended premature cessation of this trial. CONCLUSIONS: As compared with a first-line TKI alone, addition of upfront local therapy using RT statistically significantly improved PFS and OS for EGFR-mutated NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/radioterapia , Inibidores de Proteínas Quinases/efeitos adversos , Receptores ErbB/genética , Mutação
3.
Ann Transl Med ; 9(14): 1188, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34430629

RESUMO

OBJECTIVE: We collected evidence on the application of artificial intelligence (AI) in gastroenterology field. The review was carried out from two aspects of endoscopic types and gastrointestinal diseases, and briefly summarized the challenges and future directions in this field. BACKGROUND: Due to the advancement of computational power and a surge of available data, a solid foundation has been laid for the growth of AI. Specifically, varied machine learning (ML) techniques have been emerging in endoscopic image analysis. To improve the accuracy and efficiency of clinicians, AI has been widely applied to gastrointestinal endoscopy. METHODS: PubMed electronic database was searched using the keywords containing "AI", "ML", "deep learning (DL)", "convolution neural network", "endoscopy (such as white light endoscopy (WLE), narrow band imaging (NBI) endoscopy, magnifying endoscopy with narrow band imaging (ME-NBI), chromoendoscopy, endocytoscopy (EC), and capsule endoscopy (CE))". Search results were assessed for relevance and then used for detailed discussion. CONCLUSIONS: This review described the basic knowledge of AI, ML, and DL, and summarizes the application of AI in various endoscopes and gastrointestinal diseases. Finally, the challenges and directions of AI in clinical application were discussed. At present, the application of AI has solved some clinical problems, but more still needs to be done.

4.
iScience ; 12: 204-215, 2019 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-30703734

RESUMO

The nontemplating preparation of porous carbon materials by using specially designed polymer precursors for supercapacitor is attracting considerable research attention because of the more controllable frame structure and easier processes than templating methods. Herein, a deliberately designed cross-linking polyphosphamide resin with defined N and P structure is synthesized and then carbonized to obtain porous carbon material. The as-obtained porous carbon material has a specific surface area of 2,620 m2 g-1, high porosity of 1.49 cm3 g-1, and well-distributed micro/mesoporous carbon structure. Different from activation by post-added NH4H2PO4, the confined N and P in the polymer frame are confirmed to play an important role in pore structure development by forming in situ highly dispersed NH4H2PO4 during carbonization. When evaluated as the electrode material for supercapacitors, the polyphosphamide-resin-based porous carbon material demonstrates excellent capacitance (440 F g-1 under 0.5 A g-1) and high stability (retention of 93% over 10,000 cycles).

5.
Yao Xue Xue Bao ; 38(5): 325-7, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12958832

RESUMO

AIM: To study the effects of sodium magnesium fructose diphosphate (SMFD) on free calcium concentration and nitric oxide synthase activity of ischemic synaptosome, so as to explore the protective mechanisms of SMFD on cerebral ischemia. METHODS: The synaptosomes from normal rat brain were prepared by phase partition and cultured with oxygen-glucose deprivation to establish ischemic synaptosome model. The intrasynaptosomal free calcium concentration and nitric oxide synthase activity were detected separately after the synaptosomes were co-incubated with SMFD (1.3 mmol.L-1) or fructose-1, 6-diphosphate (FDP, 4.0 mmol.L-1) for 60 min. RESULTS: SMFD decreased the free calcium concentration and reduced the activity of nitric oxide synthase (NOS) of ischemic synaptosomes. Its effects were more powerful than those of FDP. CONCLUSION: SMFD may protect neurons from ischemic injury by preventing intracellular Ca2+ overload and inhibiting the activity of nitric oxide synthase.


Assuntos
Cálcio/metabolismo , Frutosedifosfatos/farmacologia , Óxido Nítrico Sintase/metabolismo , Sinaptossomos/metabolismo , Animais , Isquemia Encefálica/enzimologia , Isquemia Encefálica/metabolismo , Quelantes/farmacologia , Magnésio/química , Masculino , Óxido Nítrico Sintase/efeitos dos fármacos , Ratos , Ratos Wistar , Sódio/química
6.
ChemSusChem ; 6(4): 600-3, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23468313

RESUMO

Green nylons! Acidic ionic-liquid catalysis for the transformation of γ-valerolactone into methyl 3-pentenoate (M3P) is shown to be performed efficiently under mild conditions. M3P is obtained selectively from a reaction at 170 °C for 3.5 h in the presence of an acidic ionic liquid that has a low vapor pressure, high thermal stability, and excellent catalytic performance. A possible reaction pathway for this conversion is also presented.


Assuntos
Líquidos Iônicos/química , Lactonas/química , Valeratos/química , Catálise
7.
Bioresour Technol ; 102(3): 3471-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21094602

RESUMO

Fast pyrolysis of three wetland plants (Alligator weed, Oenanthe javanica and Typha angustifolia) in a vertical drop fixed bed reactor was investigated in this study. The experiments were carried out at different pyrolysis temperatures, and the maximum bio-oil yields achieved were 42.3%, 40.2% and 43.6% for Alligator weed, Oenanthe javanica and Typha angustifolia, respectively. The elemental composition of the bio-oil and char were analyzed, and the results show that a low temperature was appropriate for the nitrogen and phosphorus enrichment in char. GC-MS analysis shows that nitrogenous compounds, phenols and oxygenates were the main categories in the bio-oil. A series of leaching tests were carried out to examine the recovery of the nitrogen and phosphorus in the char, and the results indicate that significant fractions of nitrogen and phosphorus could be recovered by leaching process.


Assuntos
Química Verde/métodos , Calefação/métodos , Nitrogênio/isolamento & purificação , Fósforo/isolamento & purificação , Plantas/química , Áreas Alagadas
8.
Bioresour Technol ; 102(17): 8247-52, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21724386

RESUMO

Bio-chars with high adsorption capacity derived from rice-husks and corncobs were prepared at different retention times (RTs) in a pyrolysis reactor. At a fixed pyrolysis temperature, the pyrolysis RT is a key factor influencing the surface areas and functional group contents of the bio-chars, and further influencing their adsorption capacities. The results indicate that the bio-char prepared at RT of 1.6s exhibits a higher phenol adsorption capacity (589 mg g(-1)) than other bio-chars and many activated carbons reported in the literature. An adsorption mechanism based on acid-base interaction and hydrogen binding between phenol and the functional groups was proposed to elucidate the adsorption process. An economic evaluation of the use of bio-chars as adsorbents was made.


Assuntos
Biomassa , Adsorção , Fenol/química , Propriedades de Superfície
9.
Bioresour Technol ; 102(10): 6260-5, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21421305

RESUMO

An integrated biosorption-pyrolysis technology was employed to recover Pb from aqueous solution. A series of biosorption, fast pyrolysis and leaching experiments were carried out. The optimum pH and adsorbent dose for Pb adsorption from aqueous solution are 6.0 and 3.0 g L(-1), respectively. The temperature is a key factor influencing the yields of pyrolysis products, and the maximum yield of bio-oil is 45.7% at 773 K. The pyrolysis technology can effectively recover Pb from Pb polluted Typha angustifolia biomass (Pb-TAB) and its recovery efficiency is not notably influenced by temperature. According to the economic evaluation, the biosorption-pyrolysis technology has great techno-economic advantages over the conventional biosorption-leaching technology.


Assuntos
Chumbo/isolamento & purificação , Água/química , Adsorção , Biomassa , Soluções , Typhaceae/química
10.
Acta Pharmacol Sin ; 25(3): 301-5, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15000882

RESUMO

AIM: To observe the neuroprotective mechanism of modafinil on Parkinson disease (PD) models induced by 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP). METHODS: The model of PD was induced by intraperitoneally injecting MPTP into C57BL/6J mice for 4 d. Modafinil (i.p., 50 or 100 mg/kg(-1)/d(-1)) was administered at 30 min following MPTP for 4 d and for another 10 d continuously. The contents of dopamine (DA), noradrenaline (NA), 5-hydroxytryptamine (5-HT), gamma-aminobutyric acid (GABA), glutamine (Glu) in the striatum, and the contents of GABA, Glu, malondialdehyde (MDA), and glutathione (GSH) in the substantia nigra (SN) of model mice were determined. RESULTS: Modafinil (50 and 100 mg/kg) prevented against the decrease of the contents of DA, 5-HT, and NA in the striatum and GSH, GABA in the SN induced by MPTP, but reduced the increase of MDA in the SN and GABA in the striatum induced by MPTP. Modafinil preferentially inhibited striatal GABA release, but it did not change the increase of nigrostriatal Glu release induced by MPTP. CONCLUSION: The anti-oxidation and the modulation of nigrostriatal GABA and striatal NA and 5-HT release contributed to the neuroprotective effects of modafinil on PD induced by MPTP.


Assuntos
Compostos Benzidrílicos/farmacologia , Intoxicação por MPTP/metabolismo , Fármacos Neuroprotetores/farmacologia , Substância Negra/metabolismo , Ácido gama-Aminobutírico/metabolismo , Animais , Corpo Estriado/metabolismo , Dopamina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modafinila , Norepinefrina/metabolismo , Serotonina/metabolismo
11.
Zhonghua Liu Xing Bing Xue Za Zhi ; 25(5): 421-4, 2004 May.
Artigo em Zh | MEDLINE | ID: mdl-15231170

RESUMO

OBJECTIVE: To investigate hantanvirus infection of captured rodents in Haidian district and Changping district of Beijing and to type hantavirus using molecular technique. METHODS: The captured mice were classified and the density of distribution was calculated. Reverse transcription-polymerase chain reaction (RT-PCR) technique was used to amplify the partial M fragnments of hantaviruse. Several representative positive samples were sequenced and analysed by ClustalX (5.0) and DNAClub software. RESULTS: A total of 414 animals were captured, among which Battus norvegicus was the dominant group. In Haidian district, the median infection rates with hantavirus were 13.14% in Battus norvegicus and 0 in Mus musculus Linnaeus. In Changping district, the average infection rates were 17.46% in Battus norvegicus and 3.57% in Mus musculus Linnaeus. Nucleotide sequences analysis showed that the virus detected all belonged to SEO-type. They clustered with Z37 virus and could be branched into 2 different subclades. CONCLUSION: The major hosts of hantavirus in Haidian and Changping district were Battus norvegicus and the epidemic strains in the two districts of Beijing were genotyped as SEO-type. Nucleotide sequence and deduced amino acid sequence from different rodents were highly homologous, while nucleotide mutation had also been observed. Further studies are required to explore the possible virus sequence mutation.


Assuntos
Reservatórios de Doenças , Infecções por Hantavirus/veterinária , Orthohantavírus/isolamento & purificação , Doenças dos Roedores/epidemiologia , Animais , China/epidemiologia , DNA Viral/genética , Imunofluorescência , Orthohantavírus/classificação , Orthohantavírus/genética , Infecções por Hantavirus/epidemiologia , Infecções por Hantavirus/virologia , Febre Hemorrágica com Síndrome Renal/epidemiologia , Febre Hemorrágica com Síndrome Renal/veterinária , Febre Hemorrágica com Síndrome Renal/virologia , Camundongos , Epidemiologia Molecular , Filogenia , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Doenças dos Roedores/virologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA