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1.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 37(2): 142-146, 2021 Mar.
Artículo en Chino | MEDLINE | ID: mdl-34672151

RESUMEN

Objective: To screen the influencing factors of hypertensive heart disease (HHD), establish the predictive model of HHD, and provide early warning for the occurrence of HHD. Methods: Select the patients diagnosed as hypertensive heart disease or hypertensionfrom January 1, 2016 to December 31, 2019, in the medical data science academy of a medical school. Influencing factors were screened through single factor and multi-factor analysis, and R software was used to construct the logistics model, random forest (RF) model and extreme gradient boosting (XGBoost) model. Results: Univariate analysis screened 60 difference indicators, and multifactor analysis screened 18 difference indicators (P<0.05). The area under the curve (AUC) of Logistics model, RF model and XGBoost model are 0.979, 0.983 and 0.990, respectively. Conclusion: The results of the three HHD prediction models established in this paper are stable, and the XGBoost prediction model has a good diagnostic effect on the occurrence of HHD.


Asunto(s)
Cardiopatías , Aprendizaje Automático , Biomarcadores , Humanos
2.
Langmuir ; 35(42): 13663-13670, 2019 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-31549513

RESUMEN

Cellulose nanocrystals (CNCs) with excellent biodegradability are promising biomaterials for use as responsive Pickering emulsifiers. However, the high hydrophilicity of CNCs limits their emulsification ability. Some existing studies have utilized complicated covalent modification procedures to increase the hydrophobicity of CNCs. To simplify the modification process, we prepared hydrophobically modified CNCs (CNCs-M2005) via simple and controllable electrostatic interactions with thermosensitive M2005. The obtained CNCs-M2005 exhibited temperature and CO2 dual-responsive properties. Subsequently, stable oil/water Pickering emulsions were prepared using the partially hydrophobic CNCs-M2005 at 20 °C. However, demulsification occurred when the temperature increased to 60 °C. This temperature-induced demulsification resulted from the dehydration of polyethylene oxide and polypropylene oxide, causing the aggregation of the CNCs-M2005, as shown by dynamic light scattering and transmission electron microscopy experiments. In addition, demulsification was also achieved after bubbling CO2, which was attributed to the dissociation of the partially hydrophobic CNCs-M2005. The temperature and CO2 dual-responsive biosafe Pickering emulsions open up opportunity for the design of intelligent food, cosmetic, and drug delivery systems.

3.
J Colloid Interface Sci ; 540: 177-184, 2019 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-30640065

RESUMEN

HYPOTHESIS: Surfactants with temperature-sensitive polyoxyethylene (POE) chains are widely used to prepare nanoemulsions by the phase inversion temperature (PIT) method. It is therefore anticipated that surfactants with temperature-sensitive polyoxypropylene (POP) chains could also be used to prepare nanoemulsions by the PIT method. EXPERIMENT: POP surfactants were synthesized through electrostatic interactions between hydrophilic POP diamines and hydrophobic long-chain fatty acids. The synthesized POP surfactants were used as emulsifiers to prepare n-tetradecane-in-water nanoemulsions by the PIT method. Electrical conductivity measurements were used to determine the PITs of the water/POP surfactant/n-tetradecane systems. The effects of surfactant concentration, NaCl concentration, number of POP units, and degree of unsaturation of hydrocarbon chains on the PIT and the nanoemulsion droplet size were investigated. The droplet size and morphology of the nanoemulsions were characterized by dynamic light scattering and cryogenic transmission electron microscopy, respectively. FINDINGS: Nanoemulsions are formed by the PIT method using POP surfactants when the POP chains are short (∼2.5-6.1 POP units). The formation of nanoemulsions with droplet radii of 20-300 nm and spherical morphology occurs because of the temperature-dependent hydration of the short POP chains.

4.
J Colloid Interface Sci ; 536: 381-388, 2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30380437

RESUMEN

HYPOTHESIS: To obtain surfactants with superior surface activity and responsive behavior, "pseudogemini" surfactants (short for D-LCFA) are synthesized by mixing long chain fatty acids (LCFA) and polyetheramine D 230 at fixed molar ratio (2:1). Non-covalently bonded building blocks indicate that CO2-responsive aqueous foams can be obtained by utilizing such pseudogemini surfactants. EXPERIMENTS: 1H NMR and FT-IR characterizations prove that the building blocks of these surfactants are associated by electrostatic interaction. The synthesis (Brønsted acid-base reaction) is simple and eco-friendly. "Pseudogemini" structure enables D-LCFA to reduce surface tension of aqueous solution effectively, thus facilitating foam generation. Rheograms, FF-TEM and Cryo-TEM results prove that different aggregates in D-LCFA aqueous solutions lead to different foam properties. FINDINGS: Bubbling of CO2 for about 30 s leads to the rupture of aqueous foams generated by D-LCFA, while removing CO2 by bubbling of N2 at 65 °C for 10 min enables re-generation of foams. The CO2-responsive foaming properties can be attributed to dissociation of D-LCFA upon bubbling of CO2 and re-association upon removal of CO2. The effective CO2-responsive foams can be applied to many areas, such as foam fracturing, foam enhanced oil recovery or recovering of radioactive materials.

5.
Langmuir ; 34(20): 5798-5806, 2018 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-29709197

RESUMEN

Dynamic covalent surfactants have been recently reported for preparation of pH-switchable emulsions [ Sun , D. Langmuir , 2017 , 33 , 3040 ]. In this study, dynamic covalent silica (SiO2-B) nanoparticles of switchable wettability were fabricated by a pH-responsive dynamic (covalent) imine bond between hydrophilic amino silica (SiO2-NH2) nanoparticles and hydrophobic benzaldehyde molecules. The properties of SiO2-B were characterized by Fourier transform infrared spectroscopy, elemental analysis, contact angle measurement, and ζ potential measurement. The hydrophilicity and hydrophobicity of SiO2-B were shown to be readily switchable by adjusting pH between 7.8 and 3.5. At pH 7.8, SiO2-B was partially hydrophobic and adsorbed at oil-water interface to stabilize O/W Pickering emulsions, which were characterized by electrical conductivity, optical microscopy, and confocal laser scanning microscopy. Upon lowering the pH to 3.5, the dynamic covalent bond is dissociated to convert partially hydrophobic SiO2-B into highly hydrophilic SiO2-NH2 and surface-inactive benzaldehyde. Both of them desorb from oil-water interface, resulting in a rapid oil-water separation of the Pickering emulsions. Alternating stabilization and phase separation of the Pickering emulsions over 3 cycles were demonstrated by adjusting the pH. The pH-switchable Pickering emulsions show great potential in application to effective oil-water separation of emulsions.

6.
Psychogeriatrics ; 18(5): 412-420, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29761589

RESUMEN

BACKGROUND: China is an ageing society, with around 150 million people aged 60 years or older. The prevalence of dementia will increase by more than 100% in the coming 20 years. This study aimed to investigate the prevalence and effects of dementia among the community elderly in Chongqing, China. METHODS: Cluster sampling was adopted. A sample of elderly individuals aged 60 years and older was extracted as research subjects from three counties within Chongqing, China. One-on-one interviews were conducted through a general information questionnaire, and the Mini-Mental State Examination, Instrumental Activity of Daily Living Scale, and Geriatric Depression Scale were administered. The investigated data were tested by χ2 , and the effect factors of dementia were analyzed by multiple logistic regression analysis. Statistical significance was set at P < 0.05. RESULTS: We distributed 1850 questionnaire, and the response rate was 100%. However, only 1781 questionnaires were able to be used in the study. Of the 1781 elderly respondents, 186 (10.44%) presented with dementia. Our findings revealed that differences in regions, age, marital status, education level, occupation, tobacco consumption, alcohol consumption, freshwater fish consumption, exercise, intensive labour, mah-jong- and chess-playing habits, media consumption (i.e. watching TV, listening to the radio, or reading the newspaper), body mass index, hypertension, coronary heart disease, and depression were statistically significant in the prevalence of dementia (P < 0.05). CONCLUSIONS: According to multiple logistic regression analyses, living in a rural area, older age, being single, obesity, hypertension, coronary heart disease, and depression are risk factors for dementia. In contrast, cessation of smoking, freshwater fish consumption, moderate or frequent exercise, intensive labour, daily housework, outdoor activities, media consumption, and social activities are protective factors against dementia among community elderly in Chongqing, China.


Asunto(s)
Demencia/epidemiología , Estilo de Vida , Salud Rural , Población Rural/estadística & datos numéricos , Factores de Edad , Anciano , Anciano de 80 o más Años , Consumo de Bebidas Alcohólicas/epidemiología , China/epidemiología , Demencia/diagnóstico , Depresión/epidemiología , Depresión/psicología , Femenino , Humanos , Masculino , Tamizaje Masivo , Síndrome Metabólico/epidemiología , Persona de Mediana Edad , Prevalencia , Escalas de Valoración Psiquiátrica , Factores de Riesgo , Factores Socioeconómicos
7.
J Colloid Interface Sci ; 480: 198-204, 2016 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-27442147

RESUMEN

This article reports a systematic study on a highly CO2-responsive superamphiphile (D-OA) in preparation of CO2-switchable oil-in-water emulsions. The D-OA was assembled with Jeffamine D 230 and oleic acid (HOA) via electrostatic interaction, which was characterized using FT-IR, (1)HNMR, surface tension, and interfacial tension techniques. The assembled gemini-like superamphiphile D-OA was shown to have a low cmc value and adsorb quickly at the paraffin oil/water interface, decreasing the interfacial tension effectively. Highly stable O/W emulsions were obtained by mixing D-OA aqueous solution and paraffin oil. After bubbling CO2 through the stable emulsions for just 20s, quick phase separation was observed; while upon removal of CO2 by bubbling N2 at 60°C, stable emulsions were recreated. The reversible assembly and disassembly of the D-OA superamphiphile by adding or removing CO2 were considered as the cause of demulsification and re-emulsification processes. The rapid and complete demulsification of the system in response to CO2 addition and removal may have potential applications in emulsion-based fabrication/separation and enhanced oil recovery processes.

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