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1.
Environ Sci Pollut Res Int ; 30(28): 72553-72562, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37171729

RESUMEN

Carbon emissions are a major cause of global climate change. The public is aware that the world must rapidly reduce its windows to avoid the worst effects of climate change. But how this responsibility is distributed between regions, countries, and individuals has become a recurring element of debate in international debates. Most countries are willing to adopt new policies to tackle the global problem of carbon emission. Since China is a real model and the first country of initiating the goal of carbon neutrality, this study aimed to compare the different impacts of export, import, and innovation on carbon emission in 29 selected countries with the Belt and Road Initiative from 2008 to 2019. STIRPAT modeling, cross-sectional analysis, and integrated testing were used to analyze the obtained data. The results show that exports and imports have a negative effect on carbon emission, and population size and energy efficiency increase carbon emission since most countries under the BRI are developing countries, and they tend to emit greatly due to various factors. However, the adoption of green energy via innovation has a significant impact on carbon emissions. In addition, the adoption of modern technologies via innovation reduces carbon emission by increasing energy efficiency. We recommended a set of policies that can efficiently reduce the emission of carbon to achieve an eco-friendly environment in the selected countries. It is important to promote environmental sustainability and the development of professional enterprises in certain countries.


Asunto(s)
Dióxido de Carbono , Carbono , Humanos , Estudios Transversales , Dióxido de Carbono/análisis , China , Cambio Climático , Desarrollo Económico
2.
Environ Sci Pollut Res Int ; 30(9): 24299-24318, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36334204

RESUMEN

Whether the low-carbon city construction can coordinate urban economy and environment has attracted increasing attention in recent years. In this study, the impact of low-carbon city pilot (LCCP) policy on urban green total-factor productivity is systematically examined theoretically and empirically. Specifically, the biennial Malmquist-Luenberger (BML) index is adopted to measure urban green productivity. Then, propensity score matching-difference-in-differences (PSM-DID) and spatial DID model are used to quantitatively identify the local and spatial spillover effect of the LCCP policy on urban green productivity during 2004-2018 in China. The results show that (1) The LCCP policy can significantly promote urban green productivity, as confirmed through a series of robustness tests. (2) For transmission mechanism, the LCCP policy can enhance urban green productivity through energy consumption reduction and technological innovation but not through industrial structure optimization. (3) With regard to heterogeneity, cities with better transportation infrastructure, stricter environmental regulation and higher urbanization level, as well as non-resource-based cities have more significantly positive effects of the LCCP policy on urban green productivity. (4) The LCCP policy mainly relies on technological progress rather than technical efficiency improvement to drive urban green productivity. (5) The LCCP policy's effect on urban green productivity has significant positive spatial spillover feature, which can significantly promote green productivity in both pilot cities and their neighboring cities. Our findings can provide valuable insights for low-carbon city construction to promote urban sustainable development in China.


Asunto(s)
Carbono , Urbanización , Ciudades , China , Políticas , Desarrollo Económico , Eficiencia
3.
Environ Sci Ecotechnol ; 7: 100107, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36160697

RESUMEN

This paper is one of the first to offer a comprehensive analysis of the impact of green finance related policies in China, utilizing text analysis and panel data from 290 cities between 2011 and 2018. Employing the Semi-parametric Difference-in-Differences (SDID) we show that overall China's green finance related policies have led to a significant reduction in industrial gas emissions in the review period. Additionally, we found that Fintech development contributes to the depletion of sulphur dioxide emissions and has a positive impact on environmental protection investment initiatives. China is poised to be a global leader in green finance policy implementation and regulators need to accelerate the formulation of green finance products and enhance the capacity of financial institutions to offer green credit. While minimizing the systemic risk fintech poses, policy makers should encourage fintechs to actively participate in environmental protection initiatives that promote green consumption.

4.
Environ Sci Pollut Res Int ; 27(19): 23514-23528, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32307679

RESUMEN

With increasing attentions on climate change, solid wastes, over-tourism, and improved environmental awareness worldwide, eco-tourism has been widely promoted worldwide. This requires that governmental agencies at different levels should prepare appropriate policies to facilitate eco-tourism and local communities should take necessary actions to preserve their natural resources, protect their environment, and support sustainable tourism. Academically, literatures on eco-tourism have increased faster with an annual growth rate of 10-30% during the recent years. Under such a circumstance, it is important to conduct a comprehensive review so that research progress on eco-tourism can be summarized and future research directions can be identified. Based on 1771 publications published during 2001-2018, a systematic method combining bibliometric analysis and network analysis is applied in this study to uncover the dynamic trends, academic collaboration, and research hotspots related with eco-tourism. Results show that the total number of relevant publications has gradually increased. Key journals include Journal of Hospitality and Tourism Management, Annals of Tourism Research, Conservation Biology, and Biological Conservation. Authors from USA have the most publications and international co-authorships, while the most influential institution is the Chinese Academy of Science. Moreover, research keywords have been identified, including eco-tourism, management, biodiversity, national park, sustainability, and sustainable tourism. Research findings of this study provide valuable insights to further improve eco-tourism research so that this emerging research field can be proactively fostered.


Asunto(s)
Bibliometría , Publicaciones , Cambio Climático , Predicción
5.
Environ Sci Pollut Res Int ; 26(24): 24542-24551, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31236865

RESUMEN

This study investigates the possible environmental effects of economic openness, such as economic growth, foreign direct investment (FDI) inflows, and trade liberalization in South Asian Association for Regional Cooperation (SAARC) countries. The study employed panel autoregressive lag distribution (ARDL) model to evaluate the environmental effects of economic openness; causality test was also conducted to confirm short- and long-run causality among the variables under discussion. The results show that trade, FDI, capital, and economic growth in the long run have a positive correlation with environmental degradation in SAARC countries while FDI, capital, and trade inflows have a negative relation with CO2 emissions in the short run. Furthermore, economic growth by creating new job opportunities improved emissions also in the short run. FDI, trade, capital, and GDP have long-run causality with CO2 emissions. Bidirectional causality was found between GDP and CO2 emissions, unidirectional causality was also running from FDI inflows to economic growth, unidirectional causality running from capital to FDI and trade to capital. Finally, trade and economic growth also have unidirectional causality in the short run. This study concludes, therefore, that SAARC countries should invest in green energy and promote green trade liberalization.


Asunto(s)
Dióxido de Carbono/análisis , Inversiones en Salud/economía , Dióxido de Carbono/química , Clima , Desarrollo Económico , India , Internacionalidad
6.
Environ Sci Pollut Res Int ; 26(4): 3666-3674, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30535739

RESUMEN

The "resource curse" phenomenon has been the subject of extensive research, with its causes and transmission mechanisms primarily examined from the perspectives of economic development and rent seeking. Education is a major factor contributing to economically sustainable development, owing to its potential for improving cognition and skill levels and thereby enhancing worker productivity. The crowding-out or crowding-in effect of natural resource dependence on public education spending has been identified as one of the key mechanisms of the resource curse or blessing. Using panel data from 31 Chinese provinces, this empirical study revealed a positive correlation between natural resource dependence and public education expenditure, demonstrating the impact of the crowding-in effect, exerted by natural resource dependence, on public education expenditure. Abundant natural resources can provide funds for education expenditure. The sample was further divided into eastern and central and western regions. The results indicate that the crowding-out effect of natural resource dependence only affects public education expenditure in the Eastern region, while the crowding-in effect of natural resource dependence on public education expenditure in the central and western regions. Research shows that the regional differences of crowding-out or crowding-in effect are very obvious, so the government should adopt transfer payment to promote balanced regional development. Better economic and social policies will help to translate wealth from natural resources into economic growth. Thus, a "resource blessing" may emerge to replace the "resource curse." Fairly distributed and higher quality education will enhance human capital, thereby promoting economic growth from its current resource-driven pattern to a knowledge-driven pattern.


Asunto(s)
Educación/economía , Recursos Naturales , China , Desarrollo Económico , Gastos en Salud , Humanos
7.
Pet Sci ; 15(3): 657-665, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30174683

RESUMEN

This paper examines the relationships between natural resource dependence, public education investment, and human capital accumulation. It addresses why the "blessing" of abundant natural resources often turns into a "curse" in many countries and regions, focusing on the crowding-out effect of natural resources on human capital. According to our empirical analysis of provincial panel data from China, natural resource dependence is significantly and negatively correlated with human capital accumulation. The crowding-out effect of natural resources on human capital exists only in the central and western regions of China. Our introduction of an interaction term for natural resource dependence and public education investment underscores the possibility of investing in public education to reduce the crowding-out effect of natural resource dependence on human capital. The government should utilize the income of the natural resource sector to increase investment in education to enhance local human capital.

8.
Neural Regen Res ; 13(6): 1061-1065, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29926834

RESUMEN

Research on brain function after brachial plexus injury focuses on local cortical functional reorganization, and few studies have focused on brain networks after brachial plexus injury. Changes in brain networks may help understanding of brain plasticity at the global level. We hypothesized that topology of the global cerebral resting-state functional network changes after unilateral brachial plexus injury. Thus, in this cross-sectional study, we recruited eight male patients with unilateral brachial plexus injury (right handedness, mean age of 27.9 ± 5.4 years old) and eight male healthy controls (right handedness, mean age of 28.6 ± 3.2). After acquiring and preprocessing resting-state magnetic resonance imaging data, the cerebrum was divided into 90 regions and Pearson's correlation coefficient calculated between regions. These correlation matrices were then converted into a binary matrix with affixed sparsity values of 0.1-0.46. Under sparsity conditions, both groups satisfied this small-world property. The clustering coefficient was markedly lower, while average shortest path remarkably higher in patients compared with healthy controls. These findings confirm that cerebral functional networks in patients still show small-world characteristics, which are highly effective in information transmission in the brain, as well as normal controls. Alternatively, varied small-worldness suggests that capacity of information transmission and integration in different brain regions in brachial plexus injury patients is damaged.

9.
Behav Neurol ; 2018: 8351053, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29854019

RESUMEN

OBJECTIVE: The Notch signaling pathway is involved in angiogenesis induced by brain ischemia and can be efficiently inhibited by the γ-secretase inhibitor N-[N-(3,5-difluorophenacetyl)-1-alanyl]-S-phenylglycine t-butyl ester (DAPT). The aim of the present study was to noninvasively investigate the effect of DAPT treatment on angiogenesis in brain repair after stroke using magnetic resonance imaging (MRI). METHODS: Sprague-Dawley rats (n = 40) were subjected to 90 minutes of transient middle cerebral artery (MCA) occlusion and treated with PBS (n = 20) or DAPT (n = 20) at 72 hours after the onset of ischemia. MRI measurements including T2-weighted imaging (T2WI), susceptibility-weighted imaging (SWI), and cerebral blood flow (CBF) were performed at 24 hours after reperfusion and weekly up to 4 weeks using a 3-Tesla system. Histological measurements were obtained at each time point after MRI scans. RESULTS: SWI showed that DAPT treatment significantly enhanced angiogenesis in the ischemic boundary zone (IBZ) with respect to the control group, with local CBF in the angiogenic area elevated, along with increases in vascular density confirmed by histology. CONCLUSION: Treatment of ischemic stroke with DAPT significantly augments angiogenesis, which promotes poststroke brain remodeling by elevating CBF level, and these processes can be dynamically monitored and evaluated by MRI.


Asunto(s)
Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/tratamiento farmacológico , Circulación Cerebrovascular/fisiología , Dipéptidos/farmacología , Neovascularización Fisiológica/efectos de los fármacos , Receptores Notch/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Animales , Modelos Animales de Enfermedad , Imagen por Resonancia Magnética , Masculino , Ratas , Ratas Sprague-Dawley , Factores de Tiempo
11.
Chin Med Sci J ; 21(4): 223-7, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17249196

RESUMEN

OBJECTIVE: To describe the characteristic magnetic resonance imaging (MRI) appearance of cerebral schistosomiasis. METHODS: Twenty-five patients whose diagnosis of central nervous system (CNS) schistosomiasis had been pathologically (n = 8) and clinically (n = 17) confirmed were randomly selected. MRI was performed on a Signal 1. 5T MRI scanner before and after the intravenous administration of gadopentetate dimeglumine constrast medium. We reviewed the MRI studies obtained at the time of initial presentation, as well as follow-up studies obtained during and after medical treatment. RESULTS: Immunological tests in 15 patients indicated schistosomiasis haematobium. Contrast-enhanced T1-weighted images in 22 cases showed central linear enhancement surrounded by multiple enhancing punctate nodules, which appeared "arborized". Through operation and pathological examination, 8 cases had the granuloma formation of schistosomal eggs extensive surrounded by inflammation and venous congestion. And 17 cases were treated with praziquantel and corticosteroid therapy. And they were followed up for 2 months by taking MRI, which turned out to be complete resolution of the enhancing structure and edema. At follow-up, all the patients' initial symptoms also resolved. CONCLUSION: The specified MRI enhancement pattern of cerebral schistosomiasis is common in most cases of CNS schistosomiasis, so it should be taken account into the diagnosis of cerebral schistosomiasis.


Asunto(s)
Encefalopatías/diagnóstico , Encéfalo/patología , Imagen por Resonancia Magnética , Neuroesquistosomiasis/diagnóstico , Esquistosomiasis Urinaria/diagnóstico , Adolescente , Adulto , Anciano , Encefalopatías/patología , Niño , Medios de Contraste , Femenino , Estudios de Seguimiento , Gadolinio DTPA , Humanos , Aumento de la Imagen , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Neuroesquistosomiasis/patología , Esquistosomiasis Urinaria/patología
12.
Chin Med J (Engl) ; 126(6): 1138-43, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23506594

RESUMEN

BACKGROUND: Since an effective method for generating induced pluripotent stem cells (iPSCs) from human neural stem cells (hNSCs) can offer us a promising tool for studying brain diseases, here we reported direct reprogramming of adult hNSCs into iPSCs by retroviral transduction of four defined factors. METHODS: NSCs were successfully isolated and cultured from the hippocampus tissue of epilepsy patients. When combined with four factors (OCT3/4, SOX2, KLF4, and c-MYC), iPSCs colonies were successfully obtained. RESULTS: Morphological characterization and specific genetic expression confirmed that these hNSCs-derived iPSCs showed embryonic stem cells-like properties, which include the ability to differentiate into all three germ layers both in vitro and in vivo. CONCLUSION: Our method would be useful for generating human iPSCs from NSCs and provide an important tool for studying neurological diseases.


Asunto(s)
Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/metabolismo , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Diferenciación Celular/genética , Diferenciación Celular/fisiología , Células Cultivadas , Reprogramación Celular/genética , Reprogramación Celular/fisiología , Humanos , Inmunohistoquímica , Factor 4 Similar a Kruppel , Factores de Transcripción de Tipo Kruppel/metabolismo , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Transcripción SOXB1/metabolismo
13.
Chin Med J (Engl) ; 125(11): 2057-61, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22884077

RESUMEN

BACKGROUND: The Dextroscope system by Volume Interactions (Singapore) had been applied to minimally invasive neurosurgery in many units. This system enables the neurosurgeon to interact intuitively with the three-dimensional graphics in a direct manner resembling the way one communicates with the real objects. In the paper, we explored its values in pre-operation surgical planning for intracranial meningiomas resection. METHODS: Brain computed tomography (CT), magnetic resonance imaging (MRI), and magnetic resonance venography (MRV) were performed on 10 patients with parasagittal and falcine meningiomas located on central groove area; brain CT, MRI and magnetic resonance angiography (MRA) were performed on 10 patients with anterior skull base meningiomas and 10 patients with sphenoid ridge meningiomas. All these data were transferred to Dextroscope virtual reality system, and reconstructed. Then meningiomas, skull base, brain tissue, drainage vein and cerebral arteries were displayed within the system, and their anatomic relationships were evaluated. Also, the simulation operations were performed. RESULTS: For parasagittal and falcine meningiomas, the relationships of tumor with drainage vein and superior sagittal sinus were clearly displayed in the Dextroscope system. For anterior skull base and sphenoid ridge meningiomas, the relationships of tumor with bilateral internal carotid arteries, anterior cerebral arteries, middle cerebral arteries and skull base were vividly displayed within the virtual reality system. Surgical planning and simulation operation of all cases were performed as well. The real operations of all patients were conducted according to the simulation with well outcomes. CONCLUSIONS: According to the virtual reality planning, neurosurgeons could get more anatomic information about meningioma and its surrounding structures, especially important vessels, and choose the best approach for tumor resection, which would lead to better prognosis for patients.


Asunto(s)
Meningioma/cirugía , Procedimientos Neuroquirúrgicos/métodos , Anciano , Femenino , Humanos , Angiografía por Resonancia Magnética , Imagen por Resonancia Magnética , Masculino , Meningioma/diagnóstico por imagen , Meningioma/patología , Persona de Mediana Edad , Radiografía
14.
Chin Med J (Engl) ; 124(12): 1848-53, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21740844

RESUMEN

BACKGROUND: Previously we had successfully tracked adult human neural stem cells (NSCs) labeled with superparamagnetic iron oxide particles (SPIOs) in host human brain after transplantation in vivo non-invasively by magnetic resonance imaging (MRI). However, the function of the transplanted NSCs could not be evaluated by the method. In the study, we applied manganese-enhanced MRI (ME-MRI) to detect NSCs function after implantation in brain of rats with traumatic brain injury (TBI) in vivo. METHODS: Totally 40 TBI rats were randomly divided into 4 groups with 10 rats in each group. In group 1, the TBI rats did not receive NSCs transplantation. MnCl2·4H2O was intravenously injected, hyperosmolar mannitol was delivered to disrupt rightside blood brain barrier, and its contralateral forepaw was electrically stimulated. In group 2, the TBI rats received NSCs (labeled with SPIO) transplantation, and the ME-MRI procedure was same to group 1. In group 3, the TBI rats received NSCs (labeled with SPIO) transplantation, and the ME-MRI procedure was same to group 1, but diltiazem was introduced during the electrical stimulation period. In group 4, the TBI rats received phosphate buffered saline (PBS) injection, and the ME-MRI procedure was same to group 1. RESULTS: Hyperintense signals were detected by ME-MRI in the cortex areas associated with somatosensory in TBI rats of group 2. These signals, which could not be induced in TBI rats of groups 1 and 4, disappeared when diltiazem was introduced in TBI rats of group 3. CONCLUSION: In this initial study, we mapped implanted NSCs activity and its functional participation within local brain area in TBI rats by ME-MRI technique, paving the way for further pre-clinical research.


Asunto(s)
Lesiones Encefálicas/cirugía , Imagen por Resonancia Magnética/métodos , Manganeso , Células-Madre Neurales/trasplante , Animales , Lesiones Encefálicas/fisiopatología , Movimiento Celular , Aumento de la Imagen , Células-Madre Neurales/fisiología , Ratas , Ratas Sprague-Dawley
15.
Neurochem Int ; 55(7): 629-36, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19540294

RESUMEN

To study the effect of VEGF overexpression on development of cortical newborn neurons in the brains after stroke, we injected human VEGF(165)-expressive plasmids (phVEGF) into the lateral ventricle of rat brains with a transient middle cerebral artery occlusion (MCAO). An injection of phVEGF significantly promoted angiogenesis (BrdU(+)-von Willebrand's factor(+)) and reduced infarct volume in the rat brain after MCAO. Single labeling of 5'-bromodeoxyuridine (BrdU) and double staining of BrdU with lineage-specific neuronal markers were used to indicate the proliferated cells and maturation of newborn neurons in the brain section of rats at 2, 4, and 8 weeks after MCAO. The results showed that BrdU positive (BrdU(+)) cells existed in ipsilateral frontal cortex within 8 weeks after MCAO and reached the maximum at 2 weeks of reperfusion. The phVEGF treatment significantly increased BrdU(+) cells compared with the control plasmid (pEGFP) injection. Cortical neurogenesis was indicated by the presence of newborn immature (BrdU(+)-Tuj1(+)), newborn mature (BrdU(+)-MAP-2(+)), and newborn GABAergic (BrdU(+)-GAD67(+)) neurons. All these neurons declined within 8 weeks after MCAO in the controls. Injection of phVEGF significantly increased BrdU(+)-Tuj1(+) neurons at 2 weeks, and BrdU(+)-MAP-2(+) neurons and BrdU(+)-GAD67(+) neurons at 4 and 8 weeks, respectively after MCAO. Moreover, phVEGF treatment significantly increased neurite length and branch numbers of BrdU(+)-MAP-2(+) newborn neurons compared with pEGFP treatment. These results demonstrate that VEGF enhances maturation of stroke-induced cortical neurogenesis and dendritic formation of newborn neurons in adult mammalian brains.


Asunto(s)
Isquemia Encefálica/patología , Corteza Cerebral/citología , Neuritas/efectos de los fármacos , Neuronas/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/farmacología , Animales , Animales Recién Nacidos , Antimetabolitos , Western Blotting , Bromodesoxiuridina , Línea Celular , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/crecimiento & desarrollo , ADN Complementario/biosíntesis , ADN Complementario/genética , Técnica del Anticuerpo Fluorescente , Humanos , Inmunohistoquímica , Infarto de la Arteria Cerebral Media/patología , Imagen por Resonancia Magnética , Masculino , Microscopía Confocal , Neuritas/ultraestructura , Neuronas/ultraestructura , Plásmidos/genética , Ratas , Ratas Sprague-Dawley , Transfección
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