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1.
J Environ Sci (China) ; 102: 85-98, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33637268

RESUMEN

The potential for mitigating climate change is growing worldwide, with an increasing emphasis on reducing CO2 emissions and minimising the impact on the environment. African continent is faced with the unique challenge of climate change whilst coping with extreme poverty, explosive population growth and economic difficulties. CO2 emission patterns in Africa are analysed in this study to understand primary CO2 sources and underlying driving forces further. Data are examined using gravity model, logarithmic mean divisia index and Tapio's decoupling indicator of CO2 emissions from economic development in 20 selected African countries during 1984-2014. Results reveal that CO2 emissions increased by 2.11% (453.73 million ton) over the research period. Gravity centre for African CO2 emissions had shifted towards the northeast direction. Population and economic growth were primary driving forces of CO2 emissions. Industrial structure and emission efficiency effects partially offset the growth of CO2 emissions. The economic growth effect was an offset factor in central African countries and Zimbabwe due to political instability and economic mismanagement. Industrial structure and emission efficiency were insufficient to decouple economic development from CO2 emissions and relieve the pressure of population explosion on CO2 emissions in Africa. Thus, future efforts in reducing CO2 emissions should focus on scale-up energy-efficient technologies, renewable energy update, emission pricing and long-term green development towards sustainable development goals by 2030.


Asunto(s)
Dióxido de Carbono , Desarrollo Económico , África , Dióxido de Carbono/análisis , China , Industrias , Desarrollo Sostenible
2.
Int J Behav Nutr Phys Act ; 16(1): 98, 2019 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-31685026

RESUMEN

BACKGROUND: Adherence to a healthy lifestyle is associated with substantially lower risks of mortality from all causes, cardiovascular diseases, and cancer in white populations. However, little is known about the health benefits among non-white populations. Also, no previous studies have focused on respiratory disease mortality in both white and non-white populations. We assessed the relationships between a combination of healthy lifestyle factors and multiple death outcomes in Chinese adults. METHODS: This study included 487,198 adults aged 30-79 years from the China Kadoorie Biobank without heart disease, stroke, and cancer at study enrolment. We defined five healthy lifestyle factors as never smoking or smoking cessation not due to illness; non-daily drinking or moderate alcohol drinking; median or higher level of physical activity; a diet rich in vegetables, fruits, legumes and fish, and limited in red meat; a body mass index of 18.5 to 27.9 kg/m2 and a waist circumference < 90 cm (men)/85 cm (women). Cox regression was used to produce adjusted hazard ratios (HRs) relating these healthy lifestyle factors to all-cause and cause-specific mortality. RESULTS: During a median follow-up of 10.2 years (IQR 9.2-11.1), we documented 37,845 deaths. After multivariable adjustment, the number of healthy lifestyle factors exhibited almost inverse linear relationships with the risks of all-cause and cause-specific mortality. Compared with participants without any healthy factors, the hazard ratio of participants with five healthy factors was 0.32 [95% confidence interval (CI): 0.28, 0.37] for all-cause mortality. The corresponding HRs in specific cause of death were 0.42 (95% CI: 0.26, 0.67) for ischaemic heart disease, 0.21 (95% CI: 0.09, 0.49) for ischaemic stroke, 0.37 (95% CI: 0.22, 0.60) for haemorrhage stroke, 0.36 (95% CI: 0.29, 0.45) for cancer, 0.26 (95% CI: 0.14, 0.48) for respiratory diseases, and 0.29 (95% CI: 0.22, 0.39) for other causes. Theoretically, 38.5% (95% CI: 33.0, 43.8%) of all-cause mortality was attributable to nonadherence to a healthy lifestyle, and the proportions of preventable deaths through lifestyle modification ranged from 26.9 to 47.9% for cause-specific mortality. CONCLUSIONS: Adherence to a healthy lifestyle was associated with substantially lower risks of all-cause, cardiovascular, respiratory, and cancer mortality in Chinese adults. Promotion of a healthy lifestyle may considerably reduce the burden of non-communicable diseases in China.


Asunto(s)
Estilo de Vida Saludable , Enfermedades no Transmisibles/mortalidad , Cooperación del Paciente , Adulto , Anciano , China , Dieta , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mortalidad , Estudios Prospectivos
4.
Macromol Rapid Commun ; 38(13)2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28233415

RESUMEN

This communication describes polymer vesicles self-assembled from hyperbranched polymers (branched polymersomes (BPs)) as scaffolds, conceptually mimicking the natural light-harvesting system in aqueous solution. The system is constructed with hydrophobic 4-chloro-7-nitro-2,1,3-benzoxadiazole (NBD-Cl) as donors encapsulated in the hydrophobic hyperbranched cores of the vesicles and the hydrophilic Rhodamine B (RB) as acceptors incorporated on the surface of the vesicles through the cyclodextrin (CD)/RB host-guest interactions, through which the donors and acceptors are spatially separated to effectively avoid the self-quenching between donors. This vesicular light harvesting system has presented good energy transfer efficiency of about 80% in water, and can be used as the ink to write multiclolor letters. In addition, due to the giant dimension of BPs, the real-time fluorescent images of the vesicles under an optical microscope can be observed to prove the light-harvesting process. It is supposed that such a vesicular light-harvesting antenna can be used to construct artificial photosynthesis systems in the future.


Asunto(s)
Fotoquímica , Polímeros/síntesis química , Agua/química , Transferencia de Energía , Interacciones Hidrofóbicas e Hidrofílicas , Luz
5.
Langmuir ; 32(4): 991-6, 2016 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-26766236

RESUMEN

This work reports on the facile preparation of hybrid polymer vesicles with alterable armors of metal nanoparticles by using a novel hyperbranched polymer vesicle as the templates. The vesicles were prepared through the aqueous self-assembly of a hyperbranched multiarm copolymers with many tertiary amino groups on the surface, which can electrostatically complexed or coordinated with metal ions like AuCl4(-), PtCl6(2-), and Ag(+) ions. Subsequently, the vesicles coated with metal ions can be in situ reduced into metal nanoparticles, through which a series of surface-engineered vesicles (Au@vesicles, Ag@vesicles, Pt@vesicles) with an advantage of fully covered metal nanoparticles on the surface could be readily prepared. The morphologies, structures, and formation mechanism of the as-prepared hybrid vesicles were carefully characterized, and the obtained hybrid vesicles also showed great potentials in catalysis and surface-enhanced Raman scattering (SERS) applications.

6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(7): 2104-10, 2016 Jul.
Artículo en Zh | MEDLINE | ID: mdl-30035894

RESUMEN

Tri-step infrared spectroscopy method of Fourier transform infrared spectroscopy, second derivative infrared spectroscopy and two-dimensional correlation infrared spectroscopy was firstly used to discriminate six species of mushrooms belonging to the genus Lactarius and Russula. The absorption bands of the original spectrum were very similar, which were composed by protein and polysaccharides, but tiny differences were observed at the position, shape and absorption intensities of peaks. Second derivative infrared spectroscopy technology was applied to study 6 species of the samples, there were obvious differences in the range of 1 800~1 400 and 1 200~800 cm-1. Two-dimensional correlation infrared spectroscopy can improve the resolution of spectra. Therefore two-dimensional correlation infrared spectroscopy was used to study 6 kinds of mushrooms. The results showed that there are three auto-peaks in the Lactarius, four in the Russula and significant differences in the number, intensity of auto-peaks and cross peaks were observed in the range of 1 690~1 420 cm-1. In addition, the peaks quantity, position, intensity of auto-peaks and cross peaks were different in the range of 1 110~920 cm-1. It demonstrates that tri-step infrared spectroscopy technology of Fourier transform infrared spectroscopy, second derivative infrared spectroscopy and two-dimensional correlation infrared spectroscopy is a rapid and effective method for discriminating Lactarius and Russula.

7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(8): 2479-86, 2016 Aug.
Artículo en Zh | MEDLINE | ID: mdl-30074350

RESUMEN

Fourier transform infrared spectroscopy, two-dimensional correlation infrared spectroscopy and principal component analysis were used to discriminate seven species of boletus belonging to the same genus. The results showed that the absorption bands of original spectra were similar, which were mainly composed of the absorption bands of protein and polysaccharides, but tiny differences were still observed at the position and intensities of peaks. Two-dimensional correlation infrared spectroscopy technology was applied to study the sample. It showed that there are 6 auto-peaks in the Boletus brunneissimus Chiu and Boletus bicolor, 5 auto-peaks in the Boletus speciosus, 4 auto-peaks in the Boletus griseus Forst and Boletus calopus, only 3 in the Boletus edulis and Boletus aereus in the range of 1 680~1 300 cm-1. The significant differences in the position, intensity of auto-peaks and cross peaks were still observed in the range of 1 680~1 300 cm-1. Same significant differences were observed in the range of 1 150~920 cm-1. Principal component analysis was conducted on boletus with second derivative infrared spectra in the range of 1 800~800 cm-1. All the samples were distinguished and the classification accuracy of principal component analysis is up to 100%. It is demonstrated that Fourier transform infrared spectroscopy combined with two-dimensional correlation infrared spectroscopy or principal component analysis is a rapid and effective method for discriminating mushrooms.


Asunto(s)
Basidiomycota , Espectroscopía Infrarroja por Transformada de Fourier , Polisacáridos , Análisis de Componente Principal
8.
Org Biomol Chem ; 13(3): 686-90, 2015 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-25424983

RESUMEN

A miscible tetrahydrofuran-tris buffer mixture has been used to fabricate polydopamine hollow capsules with a size of 200 nm and with a shell thickness of 40 nm. An unusual non-emulsion soft template mechanism has been disclosed to explain the formation of capsules. The results indicate that the capsule structure is highly dependent on the volume fraction of tetrahydrofuran as well as the solvent, and the shell thickness of capsules can be controlled by adjusting the reaction time and dopamine concentration.


Asunto(s)
Dopamina/química , Furanos/química , Indoles/síntesis química , Nanocápsulas/química , Polímeros/síntesis química , Trometamina/química , Microscopía Electrónica de Transmisión , Nanocápsulas/ultraestructura , Tamaño de la Partícula , Propiedades de Superficie , Factores de Tiempo
9.
Zhonghua Yan Ke Za Zhi ; 51(11): 818-21, 2015 Nov.
Artículo en Zh | MEDLINE | ID: mdl-26850582

RESUMEN

OBJECTIVE: To observe the efficacy and safety of intravitreal injection of conbercept, a new drugs of VEGFR fusion proteins, on wet age-related macular degeneration (wAMD). METHODS: To analyze retrospectively the clinical data of 58 patients with wet wAMD, which was diagnosed by examination of ETDRS charts, color fundus photograph, fluorescein angiography (FFA) and optical coherence tomography (OCT), were underwent intravitreal injection conbercept 0.5 mg (0.05 ml of 10 g/L). Follow-up time was 6 to 12 months.Visual acuity (ETDRS charts letter), retinal thickness, leakage of CNV and operative complications before and after the treatment were analyzed. RESULTS: Conbercept injection therapeutic times were 3-5, the average therapeutic times were 3.05. At the end of the follow-up period, the mean letter of ETDRS charts was 50.20±12.87, increased 26.20 letters (t=2.936, P<0.01). the ETDRS charts improved 15 or more letters in 33 eyes (53.23%), decreased more than 15 letters in 2 eyes (3.23%); the average foveal thickness on OCT images were (223±74) µm after treatment, decreased significantly (t=3.669, P<0.01) ; FFA showed CNV complete closure in 34 eyes (54.84%), partial closure in 23 eyes (37.10%), no change in 5 eyes (8.06%). IOP increased in 2 eyes after treatment and recovered within one week. CONCLUSIONS: Intravitreal injection of conbercept for wAMD was well tolerated, with an improvement in BCVA, macular edema and leakage of CNV, reduce the risk of rehaemorrhagia.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Proteínas Recombinantes de Fusión/uso terapéutico , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Degeneración Macular Húmeda/tratamiento farmacológico , Angiografía con Fluoresceína , Humanos , Inyecciones Intravítreas , Edema Macular/tratamiento farmacológico , Retina , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Agudeza Visual , Degeneración Macular Húmeda/diagnóstico
10.
Clin Exp Pharmacol Physiol ; 40(9): 635-43, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23772748

RESUMEN

Icariin has been shown to attenuate diabetic nephropathy in rats by decreasing transforming growth factor-ß (TGF-ß) and type IV collagen expression, but its mode of action in glomerular mesangial cells is uncertain. The present study aimed to investigate the effect of icariin on excess mesangial type IV collagen and fibronectin accumulation induced by high glucose, and to determine the mechanism underlying its protective effects. Under high-glucose conditions, icariin diminished type IV collagen and fibronectin accumulation, as well as TGF-ß production in human and rat mesangial cells. Mesangial cells treated with icariin after TGF-ß1 exposure expressed less type IV collagen and fibronectin than those without icariin treatment, suggesting inhibition by icariin of TGF-ß1 downstream pathways. On TGF-ß1 stimulation, icariin inhibited TGF-ß canonical Smad signalling and extracellular signal-regulated kinase (ERK)1/2 signalling by decreasing Smad2/3 and ERK1/2 phosphorylation in a dose-dependent manner. U0126, which blocked the ERK1/2 pathway, exerted an additive effect on the icariin suppression of type IV collagen and fibronectin expression, enhancing the beneficial effects of icariin. The G protein-coupled oestrogen receptor 1 (GPER) antagonist, G-15, abolished the icariin-induced inhibition of type IV collagen, and fibronectin overproduction and TGF-ß signalling. Treatment of cells with fulvestrant, a downregulator of the oestrogen receptor, enhanced the action of icariin. In conclusion, icariin decreased type IV collagen and fibronectin accumulation induced by high glucose in mesangial cells by inhibiting TGF-ß production, as well as Smad and ERK signalling in a GPER-dependent manner.


Asunto(s)
Colágeno Tipo IV/metabolismo , Fibronectinas/metabolismo , Flavonoides/farmacología , Mesangio Glomerular/metabolismo , Células Mesangiales/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Factor de Crecimiento Transformador beta1/antagonistas & inhibidores , Animales , Células Cultivadas , Colágeno Tipo IV/genética , Femenino , Fibronectinas/genética , Mesangio Glomerular/efectos de los fármacos , Glucosa/farmacología , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/genética , Células Mesangiales/efectos de los fármacos , Fosforilación/efectos de los fármacos , Fosforilación/genética , Ratas , Ratas Sprague-Dawley , Receptores de Estrógenos/genética , Receptores de Estrógenos/metabolismo , Receptores Acoplados a Proteínas G/genética , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Proteína Smad2/genética , Proteína Smad2/metabolismo , Proteína smad3/genética , Proteína smad3/metabolismo , Factor de Crecimiento Transformador beta1/genética , Factor de Crecimiento Transformador beta1/metabolismo
11.
Med Eng Phys ; 110: 103860, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35999163

RESUMEN

OBJECTIVE: To investigate the clinical efficacy and safety of polaprezinc compared with rebamipide in the treatment of gastric ulcers (GU). METHODS: GU patients (n = 224) from 10 clinical centers were prospectively enrolled and randomly divided into a control (n = 113) or test (n = 111) group. The control group was treated with rebamipide tablets, while the test group was treated with polaprezinc. The primary endpoint was the effective treatment rate, which was confirmed by gastroscopy after 8 weeks of treatment. The secondary efficacy endpoint was the improvement rate of gastrointestinal symptoms after 4 and 8 weeks of treatment. RESULTS: The basic characteristics of the two groups were well balanced. For the primary efficacy endpoint, the effective rates confirmed by gastroscopy, after treatment for the test and control groups were 81.48% and 74.31% (P = 0.1557), respectively. After 4 and 8 weeks of treatments, both treatment groups had comparable improvements rates in gastrointestinal symptoms (test vs. control: 44.44% vs. 39.45% [P = 0.4559] and 81.48% vs. 77.06% [P = 0.4223]). Further, the two groups had similar adverse events and reactions to the study drugs. CONCLUSION: These findings suggest that the efficacy and safety of polaprezinc were similar to those of rebamipide in the treatment of GU.


Asunto(s)
Antiulcerosos , Carnosina , Compuestos Organometálicos , Úlcera Gástrica , Humanos , Antiulcerosos/uso terapéutico , Carnosina/uso terapéutico , Gastroscopía , Úlcera Gástrica/tratamiento farmacológico , Resultado del Tratamiento , Compuestos Organometálicos/uso terapéutico , Compuestos de Zinc/uso terapéutico
13.
Mitochondrial DNA B Resour ; 5(1): 543-544, 2020 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-33366639

RESUMEN

Cornus bretschneideri L.Henry (Cornaceae), a shrub or small tree, is a potential horticultural plant or a soil-fixing plant. In this study, the complete sequence and characterization of the chloroplast genome of C. bretschneideri was studied. The size of the chloroplast genome is 158,270 bp in length, including a large single copy region (LSC) of 87,466 bp, a small single copy region (SSC) of 18,730 bp, and a pair of inverted repeat (IR) regions with 26,037 bp. The GC content of the chloroplast genome was 37.86%. Moreover, a total of 132 functional genes were annotated, including 87 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. The neighbor-joining phylogenetic tree suggested that C. bretschneideri was closely related to C. sanguinea and C. macrophylla.

14.
J Food Biochem ; 44(4): e13163, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32030801

RESUMEN

The c9,t11-conjugated linoleic acid (CLA), which is the minor polyunsaturated fatty acid (PUFA) naturally present in butter, has gained attention due to its important preventive effect against breast cancer in vitro. In this paper, the enrichment of c9,t11-CLA from butter was optimized and the preventive effect of dietary c9,t11-CLA against breast cancer in vivo was investigated. Results showed that the concentration of c9,t11-CLA increased more than 10 times via a one-step urea complexation. Furthermore, the dietary c9,t11-CLA showed obvious preventive effect against breast cancer in decreasing the tumor weight and volume, and reducing the tumor incidence up to 50%. In addition, the expression of progesterone receptor and Ki-67 decreased significantly with the treatment of c9,t11-CLA. In conclusion, the dietary c9,t11-CLA enriched from butter showed a preventive effect against breast cancer in vivo via the inhibition of the hormonal receptor and cell proliferation. PRACTICAL APPLICATIONS: This paper provided new insight into the preparation of specific c9,t11-CLA isomer. It can be enriched from butter in large-scale with low-cost by urea complexation. Meanwhile, the enriched dietary c9,t11-CLA can be further processed into cancer prevention functional foods.


Asunto(s)
Neoplasias de la Mama , Ácidos Linoleicos Conjugados , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/prevención & control , Mantequilla , Dieta , Femenino , Humanos , Ácidos Linoleicos Conjugados/farmacología
15.
Obesity (Silver Spring) ; 28(2): 468-474, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31876384

RESUMEN

OBJECTIVE: Evidence on the association between sleep duration and obesity among adults is inconsistent. Prospective studies investigating the association in Chinese adults have been limited. This study aims to prospectively evaluate sleep duration in relation to subsequent weight gain and general and central obesity risk among Chinese adults. METHODS: A total of 21,958 participants aged 30 to 79 years reported their daily sleep duration. Obesity indicators were objectively measured; then significant weight gain (≥ 5 kg) and general and central obesity were modeled as the outcome. Logistic regression models were used to estimate odds ratios and 95% CIs. RESULTS: Average sleep duration was 7.5 hours at baseline. During 8.0 ± 0.8 years of follow-up, participants who reported sleeping ≤ 6 hours had higher risk for significant weight gain than those who slept 7 hours (multivariable-adjusted odds ratio: 1.13; 95% CI: 1.02-1.29). The association was stronger among those who were physically inactive at baseline (P = 0.04 for interaction). Short sleep duration was also associated with subsequent incident central obesity, with odds ratio of 1.13 (95% CI: 1.00-1.28), but not with incident general obesity (P = 0.31). CONCLUSIONS: Compared with those who slept 7 hours per day, short sleepers had an increased risk of significant weight gain and central obesity.


Asunto(s)
Obesidad Abdominal/epidemiología , Obesidad Abdominal/etiología , Obesidad/epidemiología , Obesidad/etiología , Sueño/fisiología , Aumento de Peso/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Pueblo Asiatico , Índice de Masa Corporal , China/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Factores de Tiempo
16.
JAMA Netw Open ; 3(10): e2018721, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-33006619

RESUMEN

Importance: There is some support for the existence of genetic associations between adiposity and certain hepatobiliary diseases in Western populations. However, there is little evidence of such genetic associations in China, where the causes of these diseases may differ from those in Western populations and the mean body mass index (BMI) is much lower. Objectives: To compare the observational associations of BMI with hepatobiliary diseases and liver biomarkers with the genetic associations between BMI and these factors and to assess whether the genetic associations of BMI with liver diseases differed by hepatitis B virus infection status. Design, Setting, and Participants: This cohort study used data from the prospective China Kadoorie Biobank, including 473 938 adults aged 30 to 79 years without hepatobiliary diseases at baseline from 10 diverse areas in China from June 25, 2004, to July 15, 2008. A random sample of 75 736 participants with genotyping data was included in the Mendelian randomization analysis. Follow-up was completed January 1, 2017 (median [interquartile range] length of follow-up, 10.2 [9.2-11.1] years). Data were analyzed from January to October 2019. Exposures: Measured BMI obtained during the baseline survey and genetically instrumented BMI derived using 92 single-nucleotide variations. Main Outcomes and Measures: Incident cases of hepatobiliary diseases, liver enzymes, fatty liver index, and fibrosis score. Results: Among 473 938 individuals (276 041 [58.2%] women), the mean (SD) age was 52 (10.9) years and mean (SD) BMI was 23.8 (3.4). Baseline BMI was associated with higher risks of chronic liver disease (adjusted risk ratio per 1-SD increase, 1.14; 95% CI, 1.11 to 1.17) and gallbladder disease (adjusted risk ratio per 1-SD increase, 1.29; 95% CI, 1.27 to 1.31), with heterogeneity by disease subtype (P < .001). Genetically instrumented BMI was associated with higher risks of chronic liver disease (risk ratio per 1-SD increase, 1.55; 95% CI, 1.08 to 2.24) and gallbladder disease (risk ratio per 1-SD increase, 1.40; 95% CI, 1.11 to 1.76), with no heterogeneity between subtypes. A meta-analysis of the genetic associations in China Kadoorie Biobank and those calculated in UK Biobank gave a risk ratio of 1.55 (95% CI, 1.30 to 1.84) for chronic liver disease and 1.42 (95% CI, 1.22 to 1.64) for gallbladder disease. In the China Kadoorie Biobank study, there were positive genetic associations of BMI with liver enzymes, steatosis, and fibrosis scores, consistent with observational associations. The genetic associations of BMI with liver diseases and biomarkers did not differ by hepatitis B virus infection status. Conclusions and Relevance: In this cohort study of a relatively lean Chinese population, there were positive genetic associations of BMI with hepatobiliary diseases. These results suggest that maintaining a healthy weight through diet and physical activity may help prevent hepatobiliary diseases.


Asunto(s)
Pueblo Asiatico/genética , Biomarcadores/sangre , Índice de Masa Corporal , Enfermedades del Sistema Digestivo/genética , Enfermedades del Sistema Digestivo/fisiopatología , Predisposición Genética a la Enfermedad , Delgadez/genética , Adulto , Anciano , China/epidemiología , Enfermedades del Sistema Digestivo/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo
17.
Artículo en Inglés | MEDLINE | ID: mdl-31877844

RESUMEN

The environmental footprints of China's high-speed railway (HSR) have attracted much attention nationally and internationally. Although there is some research focusing on CO2 emissions, a comprehensive environmental impacts assessment of HSR construction is still lacking. In this study, the emissions of the Beijing-Tianjin intercity HSR line was calculated using a hybrid input-output life cycle assessment method to quantify the environmental impacts of HSR throughout its construction. The environmental footprints during the construction stage were analyzed in terms of different subsystems and sectors. The results showed that bridges contribute the largest environmental footprints at approximately 60%, followed by rail and electric multiple unit (EMU) systems. The top three sectors that contribute to pollutant emissions are the metal smelting and rolling industry, transport equipment manufacturing, and non-metallic mineral production. CO2 and NOx are the major pollutants directly emitted by site equipment operation. More chemical oxygen demand (COD), total phosphorus (TP), total nitrogen (TN), and petroleum are emitted in EMU production than in rail construction, while NH3-N is emitted more in rails instead. Cd, Pb, As, and Hg are the significant pollutants in the metal smelting and rolling industry, whereas Cr, Cu, and Zn are the main heavy metal emissions in the transport equipment manufacturing sector. Heavy metals are the main types of environmental footprints in bridges, stations, and electric systems. Water pollutants are the main environmental impacts for rail and EMU systems, and the emissions of air pollutants are significant in subgrades. The production efficiency of upstream materials, desulfurization and denitration in fossil combustion, and the length of the bridge construction should be considered for an HSR under construction, in order to become environmentally friendly and sustainable.


Asunto(s)
Contaminación Ambiental/análisis , Vías Férreas , Beijing , China , Ambiente , Monitoreo del Ambiente
18.
Mitochondrial DNA B Resour ; 4(2): 3356-3357, 2019 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-33365991

RESUMEN

Elymus tangutorum (Nevski) Handel-Mazzetti (Poaceae: Triticeae), a hexaploid perennial herb, is a kind of forage plant with large biomass. In this study, the complete plastome sequence of E. tangutorum was reported. The size of the plastome is 134,949 bp in length, including a large single copy region (LSC) of 80,556 bp, a small single copy region (SSC) of 12,767 bp, and a pair of inverted repeat (IR) regions with 20,813 bp. Moreover, a total of 131 functional genes were annotated, including 85 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. The maximum likelihood (ML) phylogenetic tree suggested that E. tangutorum was closely related to Elymus libanoticus and Dasypyrum villosum.

19.
Artículo en Zh | MEDLINE | ID: mdl-16775410

RESUMEN

Photosynthetic electron transport and light energy allocation were studied in the alpine plants Anisodus tanguticus (Maxim.) Pascher and Rheum tanguticum Maxim. ex Balf on the Qinghai-Tibet Plateau by using gas exchange and chlorophyll fluorescence. The results indicated that apparent quantum yield (AQY) of leaves of A. tanguticus was marginally higher than that of R. tanguticum although it had a lower maximum net photosynthetic rate (Pmax). The net photosynthetic rate (P(n)) of A. tanguticus was higher than R. tanguticum within the range of middle photosynthetic photon flux density (PPFD). However, the P(n) in R. tanguticum increased concomitantly with PPFD and did not appear to show light saturation of P(n) even under 2000 micromol m(-2) s(-1) which is similar to full light in summer (Fig.1). Increasing the PPFD to 1200 micromol m(-2) s(-1) decreased the ratio of carboxylation rate to total photosynthetic electron flow rate (J(C)/J(F)) although increased the ratio of photorespiration (J(O)/J(F)) for both species. Both J(C)/J(F) and J(O)/J(F) stabilized with a PPFD of more than 1200 micromol m(-2) s(-1) (Fig.2). The changes in the ratios of Rubisco oxygenation to carboxylation (V(O)/V(C)) were similar to changes to J(O)/J(F) (Fig.3). The increase of thermal energy dissipation (D) in A. tanguticus was higher than R. tanguticum with increased PPFD (Fig.4). It can be concluded that the two species adopt different mechanisms to cope with increased solar radiation. Increasing the fractions of PSII thermal energy dissipation and electron transport through photorespiration were the main adaptations in A. tanguticus. Enhancement of photosynthetic capacity with increased PPFD to balance the higher light energy absorbed by leaves is considered the main adaptation for R. tanguticum.


Asunto(s)
Luz , Fotosíntesis/efectos de la radiación , Rheum/efectos de la radiación , Solanaceae/efectos de la radiación , Transporte de Electrón/fisiología , Transporte de Electrón/efectos de la radiación , Fotosíntesis/fisiología , Plantas Medicinales/fisiología , Plantas Medicinales/efectos de la radiación , Rheum/fisiología , Solanaceae/fisiología , Tibet
20.
Huan Jing Ke Xue ; 36(3): 1075-83, 2015 Mar.
Artículo en Zh | MEDLINE | ID: mdl-25929079

RESUMEN

Grazing is one of the main artificial driving forces for the degradation succession process of alpine meadow. In order to quantitatively study the temperature sensitivity of alpine meadow ecosystem respiration in different degradation stages, we conducted the research in Haibei Alpine Meadow Ecosystem Research Station, CAS from July 2003 to July 2004. The static chamber-chromatography methodology was used to observe the seasonal changes of alpine scrub ecosystem respiration flux during different degradation stages. The results showed that: (1) The seasonal changes of ecosystem respiration flux in different degradation stages of alpine shrub presented a unimodal curve. The maximum appeared in August and the minimum appeared during the period from October to next April. The degradation succession process significantly decreased the ecosystem respiratory CO2 release rate. The respiratory rate ranges of alpine Potentilla fruticosa scrub (GG), Kobresia capillifolia meadow (GC) and bare land (GL) were 34.21-1 168.23, 2.30-1 112.38 and 20.40-509.72 mg (m2 x h)(-1), respectively. The average respiration rate of GG was 1.29 and 2.56 times of that of GC and GL, respectively; (2) Temperature was the main factor that affected the ecosystem respiration rate, and contributed 25% - 79% of the variation of the ecosystem respiration. The degradation succession process significantly changed the correlation between ecosystem respiration rate and temperature. The correlation (R2) between ecosystem respiration rate and each temperature indicator (T(s), T(d) and T(a)) was reduced by 47.23%, 46.95% and 55.28%, respectively when the ground vegetation disappeared and the scrub was degraded into secondary bare land; (3) The difference of Q10 between warm and cool seasons was significant (P < 0.05), and the value of cold season was larger than that of warm season. Degradation succession process apparently changed the temperature sensitivity of ecosystem respiration. The Q10 values of GG, GC and GL were 2.38, 2.91 and 1.62, respectively. Q10 of GC was increased by 22.26% and that of GL was decreased by 31.93% compared with that of GG.


Asunto(s)
Pradera , Potentilla , Suelo/química , Temperatura , China , Estaciones del Año
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