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1.
Proc Natl Acad Sci U S A ; 121(12): e2306771121, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38466846

RESUMO

Addressing the total energy cost burden of elderly people is essential for designing equitable and effective energy policies, especially in responding to energy crisis in an aging society. It is due to the double impact of energy price hikes on households-through direct impact on fuel bills and indirect impact on the prices of goods and services consumed. However, while examining the household energy cost burden of the elderly, their indirect energy consumption and associated cost burden remain poorly understood. This study quantifies and compares the direct and indirect energy footprints and associated total energy cost burdens for different age groups across 31 developed countries. It reveals that the elderly have larger per capita energy footprints, resulting from higher levels of both direct and indirect energy consumption compared with the younger age groups. More importantly, the elderly, especially the low-income elderly, have a higher total energy cost burden rate. As the share of elderly in the total population rapidly grows in these countries, the larger per capita energy footprint and associated cost burden rate of elderly people would make these aging countries more vulnerable in times of energy crises. It is therefore crucial to develop policies that aim to reduce energy consumption and costs, improve energy efficiency, and support low-income elderly populations. Such policies are necessary to reduce the vulnerability of these aging countries to the energy crisis.


Assuntos
Características da Família , Pobreza , Humanos , Idoso , Países Desenvolvidos , Envelhecimento , Política Pública
2.
Pestic Biochem Physiol ; 203: 106010, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39084803

RESUMO

Thiram, a prevalent dithiocarbamate insecticide in agriculture, is widely employed as a crop insecticide and preservative. Chronic exposure to thiram has been linked to various irreversible damages, including tibial cartilage dysplasia, erythrocytotoxicity, renal issues, and immune system compromise. Limited research exists on its effects on reproductive organs. This study investigated the reproductive toxicology in mouse testes exposure to varying concentrations (0, 30, 60, and 120 mg/kg) of thiram. Our study uncovered a series of adverse effects in mice subjected to thiram exposure, including emaciation, stunted growth, decreased water intake, and postponed testicular maturation. Biochemical analysis in thiram-exposed mice showed elevated levels of LDH and AST, while ALP, TG, ALT, and urea were decreased. Histologically, thiram disrupted the testis' microarchitecture and compromised its barrier function by widening the gap between spermatogenic cells and promoting fibrosis. The expression of pro-apoptotic genes (Bax, APAF1, Cytc, and Caspase-3) was downregulated, whereas Bcl-2 expression increased in thiram-treated mice compared to controls. Conversely, the expression of Atg5 was upregulated, and mTOR and p62 expression decreased, with a trend towards lower LC3b levels. Thiram also disrupted the blood-testis barrier, significantly reducing the mRNA expression of zona occludens-1 (ZO-1) and occludin. In conclusion, chronic exposure to high thiram concentrations (120 mg/kg) caused testicular tissue damage, affecting the blood-testis barrier and modulating apoptosis and autophagy through the Bcl-2/Bax and mTOR/Atg5/p62 pathways. This study contributes to understanding the molecular basis of thiram-induced reproductive toxicity and underscores the need for further research and precautions for those chronically exposed to thiram and its environmental residuals.


Assuntos
Apoptose , Proteína 5 Relacionada à Autofagia , Autofagia , Barreira Hematotesticular , Proteínas Proto-Oncogênicas c-bcl-2 , Serina-Treonina Quinases TOR , Testículo , Tiram , Proteína X Associada a bcl-2 , Animais , Masculino , Apoptose/efeitos dos fármacos , Camundongos , Serina-Treonina Quinases TOR/metabolismo , Barreira Hematotesticular/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testículo/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteína 5 Relacionada à Autofagia/metabolismo , Proteína 5 Relacionada à Autofagia/genética , Autofagia/efeitos dos fármacos , Tiram/toxicidade , Proteína X Associada a bcl-2/metabolismo , Proteína X Associada a bcl-2/genética , Proteína Sequestossoma-1/metabolismo , Proteína Sequestossoma-1/genética , Inseticidas/toxicidade , Transdução de Sinais/efeitos dos fármacos
3.
J Environ Manage ; 309: 114680, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35168132

RESUMO

The shortage of water and energy are hindering the rapid development of the regional economy in recent years. Therefore, exploring the synergy of water and energy and managing the two resources comprehensively is conducive to the sustainable development of the economy. Based on the multi-regional input-output (MRIO) model, this study proposed a new assessment framework for investigating the water-energy (WE) relationship. We used this novel framework to identify the relationships in different sectors. The achieved results are as follows. First, water and energy are closely related in many sectors, including agriculture, extractive sector, petroleum, coking, and nuclear fuel processing sector, and other sectors. However, the construction sector, textile and clothing sector, and wood processing and furniture manufacturing sector showed low correlation (p > 0.05). Second, on the whole, the WE relationship has been improving. Among the eight regions, the relationship varies greatly, and the Southern coastal region has the best relationship (r = 0.78). Third, the spatial distribution of water and energy footprints shows high agreement. Although the virtual water and energy flows alleviated the energy pressure in Coastal areas, it has aggravated the water and energy shortages in Central areas. Therefore, identification of key sectors and construction of suitable policies may help alleviate the contradiction between water and energy shortages and drive regional economic development.


Assuntos
Abastecimento de Água , Água , Agricultura , China , Recursos Hídricos
4.
Sci Bull (Beijing) ; 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39183110

RESUMO

Achieving net-zero CO2 emissions is the current main focus of China's carbon neutrality goal. However, non-CO2 greenhouse gases (GHGs) are more powerful climate forcers, making their emission reduction an opportunity to rapidly mitigate future warming. Here, we evaluate non-CO2 mitigation potentials, costs and climate benefits in the context of China's carbon neutrality goals. The assessment is conducted by coupling the integrated assessment model GCAM with a climate emulator. The findings indicate that mitigation technologies can largely reduce fluorinated gas emissions from industrial sectors, but long-term non-CO2 reductions of energy sector activities rely heavily on fuel switching. Furthermore, the cumulative costs of deploying non-CO2 mitigation technologies are projected to be less than 10 % of the total costs of achieving carbon neutrality from 2020 to 2060. If non-CO2 mitigation measures are included in the overall mitigation portfolio, the benefits of avoided warming would by far outweigh the total mitigation cost increase. Our results thus highlight that incorporating a wider suite of GHGs into climate change mitigation strategies can enhance the cost-effectiveness of mitigation efforts.

5.
Sci Total Environ ; 951: 175539, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39151613

RESUMO

Agricultural product demand driven by population and economic growth poses challenges to water, land, and energy utilization, and this increasing local demand is largely met through trade. However, the efficiency and nexus pattern of the water, land, and energy embodied in agricultural trade are not well understood. This study uses the multi-regional input-output framework to analyze agricultural water, land, and energy utilization efficiency of resource footprints per unit economic output as well as their transfer and nexus pattern in global agricultural trade for 1995-2019. The results show that many international agricultural trade paths are inefficient in the water, land, and energy resource use because the agricultural products in these paths are exported from relatively low- to high-efficiency economies/regions. However, these inefficient transfer paths show an increasing trend over the study period. Regarding the water-land-energy nexus, conflicts are prevalent in land-energy and water-energy couplings. Most trade paths are conducted to alleviate the pressure on a specific resource, inadvertently increasing the pressure on other resources. Although agricultural trade is important for meeting global food demands, it is not consistently beneficial to the local environment when considering agricultural resources use efficiency. This study is expected to improve our understanding of agricultural trade impacts to the agricultural resources and support the sustainable development of global agriculture.

6.
Talanta ; 273: 125908, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38503119

RESUMO

A highly sensitive and selective upconversion near-infrared (NIR) fluorescence and colorimetric dual readout hydrogen sulfide (H2S) nanoprobe was constructed based on the excellent NIR fluorescence emission performance of upconversion nanomaterials (UCNPs), the specific recognition effect of synergistically synthesized gold nanoflowers (trypsin-stabled AuNFs (Try-AuNFs)) and the effective NIR fluorescence quenching capability. In this assay, the sensing strategy included three processes. First of all, the synthesized UCNPs can emit 803 nm NIR fluorescence when they were excited by 980 nm excitation light. Secondly, as a result of the principle of fluorescence resonance energy transfer (FRET), Try-AuNFs can effectively quench the NIR fluorescence of UCNPs at 803 nm, which can effectively improve the signal-to-background ratio of nanoprobes, thereby improving the sensitivity of the probes. Thirdly, in the presence of H2S, the Try protective layer on the surface of Try-AuNFs was specifically penetrated, which will subsequently cleave Try-AuNFs via the strong S-Au bond. As such, the NIR fluorescence of UCNPs will be restored, achieving high selectivity and sensitivity detection of H2S. Under optimized conditions, the linear response range of H2S was 0.1-300 µM, and the detection limit was 53 nM. It is worth noting that the Try on the surface of Try-AuNFs via the synergistic effect can increase the steric hindrance of the probe, and this can effectively prevent the interaction between the probe with biothiols (cysteine (Cys), homocysteine (Hcy)) and other natural amino acids (non-thiol-containing) with resultant in the high selectivity regarding the detection of H2S in human serum, which is unlikely to be achieved by AuNFs synthesized by the gold seed method (Se-AuNFs). This work not only provided a new type of UCNPs fluorescence quencher and recognition unit, but also exemplified that the use of the physical properties (steric hindrance) of protein ligands on the surface of nanoflowers can improve the specificity of the probe. This will provide new ideas for the design of other nanoprobes.


Assuntos
Sulfeto de Hidrogênio , Nanoestruturas , Humanos , Ouro/química , Transferência Ressonante de Energia de Fluorescência/métodos , Cisteína
7.
PNAS Nexus ; 2(7): pgad209, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37469929

RESUMO

Understanding the impact of climate fiscal policies on vulnerable groups is a prerequisite for equitable climate mitigation. However, there has been a lack of attention to the impacts of such policies on the elderly, especially the low-income elderly, in existing climate policy literature. Here, we quantify and compare the distributional impacts of carbon pricing on different age-income groups in the United States, the United Kingdom, and Japan and then on different age groups in other 28 developed countries. We find that the elderly are more vulnerable to carbon pricing than younger groups in the same income group. In particular, the low-income elderly and elderly in less wealthy countries face greater challenges because carbon pricing lead to both higher rate of increase in living cost among low-income elderly and greater income inequality within the same age group. In addition, the low-income elderly would benefit less than the younger groups within the same income group in the commonly proposed carbon revenues recycling schemes. The high vulnerability of the low-income elderly to carbon pricing calls for targeted social protection along with climate mitigation polices toward an aging world.

8.
Sci Total Environ ; 831: 154933, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35367542

RESUMO

As the third pole of the world, the Qinghai-Tibet Plateau (QTP) has a very special climate and geographical environment. In the past 20 years, with the increasing demand for clean energy, more than ten hydropower stations have been built. The impacts of these hydropower stations on riparian vegetation (RV) have only been described qualitatively in previous studies, while the contribution of dams and meteorological variables to riparian vegetation has not been quantitatively assessed. This study selected eight representative large-scale hydropower stations in the QTP, calculated and analyzed the dynamics of the standardized difference vegetation index (NDVI) of the RV pre-and post the dams construction, combined with the measured temperature and precipitation data to explore the driving factors of RV changes. The results show that the dams promoted the growth of RV and they were the main contributor (>50%) while precipitation and temperature had relatively small impacts. The effect of dams varies for different regions, compared with the sub-cold regions, it was more significant in humid and semi-humid regions of temperate zone. The dams affected RV in an indirect way through regulating the microclimate, promoting precipitation and slowing down the rate of temperature rise and these effects may come from the increase of the upstream water surface area.


Assuntos
Mudança Climática , Clima , China , Ecossistema , Meteorologia , Temperatura , Tibet
9.
PLoS One ; 17(2): e0263992, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35180255

RESUMO

Increasing human longevity is of global interest. The present study explored the prediction of longevity from both individual perspective and family perspective based on demographic and psychosocial factors. A total of 186 longevous family members and 237 ordinary elderly family members participated in a cross-sectional study, and a sample of 62 longevous elderly and 57 ordinary elderly were selected for comparative research. The results showed that it was three times more female than male in longevous elderly group. Up to 71.2% of longevous elderly had no experience in education, which was significantly lower than that of ordinary elderly. Due to such extreme age, more widowed (81.4%) elderly than those in married (18.6%). Less than one-seventh of the longevous elderly maintained the habit of smoking, and about one-third of them liked drinking, both were significantly lower than that of ordinary elderly. In terms of psychosocial factors, longevous elderly showed lower neuroticism and social support, while higher extraversion, compared with the ordinary elderly. However, there were no significant differences between the two family groups in demographic and psychosocial variables, except longevous families showing lower scores in neuroticism. Regression analysis found that neuroticism, social support and smoking habit had significant impact on individuals' life span, then, neuroticism and psychoticism were the key factor to predict families' longevity. We conclude that good emotional management, benign interpersonal support, and moderation of habits are important factors for individual longevity, and the intergenerational influence of personality is closely related to family longevity.


Assuntos
Família , Longevidade , Personalidade , Idoso , Idoso de 80 Anos ou mais , Feminino , Estilo de Vida Saudável , Humanos , Expectativa de Vida/tendências , Masculino , Fatores Sexuais , Fatores Socioeconômicos
10.
Sci Total Environ ; 806(Pt 2): 150666, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34597542

RESUMO

Water consumption, energy use, and carbon emission are three related key anthropogenic impacts on the natural environment. China is the largest carbon emitter and energy consumer, with the serious unevenly distributed water resources. Therefore, investigating the water-energy-carbon (WEC) nexus is important for China's environmental footprint reduction. This study explores the relation between water utilization, energy consumption, and carbon emission in China, based on a multiregional input-output (MRIO) analysis. The WEC nexus is discussed comprehensively in consideration of the utilization of water and energy and the emission of carbon, as well as the trade to and from and the consumption activities in different sectors and provinces. Results show that water, energy, and carbon present significant consistency in production and consumption processes. Sectors with higher consumption coefficients dominate the transfer of virtual WEC. Although virtual WEC mainly transfers from less developed regions to relatively developed regions, Category 1 (i.e., WEC all import) and category 2 (i.e., WEC disaccord) present opposite results to and category 3 (i.e., WEC all export) provinces in terms of W-E and W-C nexus. The net water and energy transfers are significantly positively correlated in category 1 provinces, whereas both sides are negatively correlated in category 2 and 3 provinces. This phenomenon also exists in the relationship between net water and carbon transfers. The virtual water, as well as energy and carbon export pressures are dispersed in these export provinces. Findings of this study are expected to assist the government in decreasing the environmental footprints and achieve sustainable development in China.


Assuntos
Carbono , Água , Carbono/análise , China , Recursos Hídricos
11.
Environ Sci Pollut Res Int ; 29(16): 23595-23606, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34807389

RESUMO

Understanding the spatiotemporal patterns of carbon footprints (CFs) of grains production is important to formulate regional heterogeneous greenhouse gas (GHG) mitigation strategies. This study evaluates the CFs, farm CFs (FCFs: CFs of per unit area), and production CFs (PCFs: CFs of per unit yield) of main grains production in China based on a new scale data set: agricultural statistics data of over 300 prefecture-level regions. A comparison of CFs of main grains production between main producing area (MPA) and non-main producing area (NMPA) are firstly discussed on a totally new scale. Results show that the CFs of main grains production of MPA accounts for 54-57% of country's total although the area of farmland of MPA only accounts for 42%. The PCF and FCF of rice production are higher in MPA, while those of wheat and maize production are lower in MPA. It implies that there are less GHG emission of rice (main paddy grain) productions in NMPA and less GHG emission of wheat and maize (main dryland grains) production in MPA. In additional, the PCF of rice shows growth, while that of wheat and maize shows decline from 2008 to 2017. The growth of PCF of rice is mainly driven by the rise of PCF in MPA. Findings are expected to improve the understanding patterns of China's CF of main grains production and subsequently contribute to GHG mitigation.


Assuntos
Gases de Efeito Estufa , Oryza , Agricultura , Pegada de Carbono , China , Efeito Estufa , Gases de Efeito Estufa/análise , Triticum , Zea mays
12.
J Diabetes Investig ; 13(11): 1805-1813, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35678496

RESUMO

AIMS/INTRODUCTION: Insulin sensitivity and ß-cell function are affected by lipid metabolism disorders, even before the onset of type 2 diabetes. People are in the postprandial state most of the time. Therefore, identifying postprandial hyperlipemia is important. This study aimed to assess patients with abnormalities in lipid metabolism, but with normal glucose tolerance, using oral fat tolerance testing (OFTT) to identify defects in insulin sensitivity and ß-cell function. MATERIALS AND METHODS: We included 248 volunteers with normal glucose tolerance who underwent OFTT. They were divided into three groups in accordance with their fasting and 4-h postprandial triglyceride (TG) concentrations. Their lipid concentrations during OFTT were compared. The disposition index (DI) was applied to estimate ß-cell function, and the Matsuda insulin sensitivity index (ISIM ) was used to assess insulin sensitivity. We used multiple linear regression analysis to estimate the relationships of fasting and postprandial TG concentrations with ß-cell function and insulin sensitivity . RESULTS: The changes in TG concentrations during OFTT were more marked than those in low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol or total cholesterol concentrations. As lipid metabolism deteriorated, the ISIM and the DI gradually decreased. Multiple linear regression analysis showed that fasting and 4-h postprandial TG concentrations affected LnISIM and LnDI. CONCLUSIONS: In individuals with normal glucose tolerance, ß-cell function and insulin sensitivity gradually decrease with a deterioration in the lipid profile. Not only fasting TG, but also postprandial TG concentrations are independent risk factors for impaired ß-cell function and insulin resistance.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Humanos , Resistência à Insulina/fisiologia , Glucose/metabolismo , Teste de Tolerância a Glucose , Triglicerídeos , Período Pós-Prandial , HDL-Colesterol , Insulina , Glicemia/análise
13.
Front Endocrinol (Lausanne) ; 13: 831435, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35250883

RESUMO

BACKGROUND: Dyslipidemia has become increasingly prevalent in recent decades. Blood lipid concentrations are significantly influenced by diet; however, postprandial triglyceride concentration (PTG) is not often measured. PTG can reflect the risks of diabetes and cardiovascular disease, but not all individuals would benefit from PTG testing. OBJECTIVE: The aim of the present study was to determine the PTG response in a Chinese cohort and identify who would benefit from diagnostic PTG measurement. METHODS: A total of 400 Chinese adults were enrolled and underwent oral fat tolerance test (OFTT), which was well tolerated. The participants were assigned to groups according to their fasting triglyceride concentration to evaluate the usefulness of PTG testing. A PTG concentration > 2.5 mmol/L was defined as high (HPTG). RESULTS: Of the 400 participants, 78.9% showed an undesirable PTG response. Those with FTG ≥1.0 mmol/L had a delayed PTG peak and higher peak values. Seventy-five percent of those with 1.0 mmol/L ≤FTG <1.7 mmol/L had HPTG, of whom 18.6% had impaired glucose tolerance. CONCLUSIONS: The present data confirm the previously reported predictive value of PTG testing. Moreover, the findings indicate that Chinese people with FTGs of 1.0 -1.7 mmol/L may benefit most from the identification of postprandial hyperlipidemia through OFTT because more than half of them have occult HPTG, which may require treatment. Thus, the detection of HPTG using an OFTT represents a useful means of identifying dyslipidemia and abnormal glucose metabolism early. CLINICAL TRIAL REGISTRATION: [http://www.chictr.org.cn/index.aspx], identifier ChiCTR1800019514.


Assuntos
Dislipidemias , Período Pós-Prandial , Adulto , China/epidemiologia , Dislipidemias/diagnóstico , Humanos , Lipídeos , Triglicerídeos
14.
Environ Sci Pollut Res Int ; 29(14): 20617-20631, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34739671

RESUMO

The freshwater environment of watersheds in the Tibetan Plateau is bound with the safety of the Asian Water Tower. In this study, nitrogen (N) and phosphorus (P) loads delivered to freshwater and the associated gray water footprint (GWF) in the agriculture, tourism, domestic life, and industrial sectors were estimated to assess the seasonal and annual characteristics of the water pollution levels (WPLs) in the Lhasa River Basin from 2006 to 2018, and WPL calculations were compared with actual water quality measurements from 2017 to 2018. We found that more than 90% of the GWF came from anthropogenic sources. From the perspective of the whole basin, domestic life was the largest contributor to both N-related GWFs (52%) and P-related GWFs (50%), followed by agriculture for N-related GWFs (32%) and tourism industry for P-related GWFs (30%). The N emissions into the freshwater environment exceeded the maximum assimilation capacity of the watersheds in individual years at both seasonal and annual scales, while P emissions were completely within the pollution assimilative capacity. Besides, we found the serious N pollution near irrigation areas at the seasonal scale (WPL = 2.7 and TN = 1.11 mg/L). The prosperity of tourism has led to a tenfold increase in N-related GWFs and a fivefold increase in P-related GWFs for the tourism industry near the Lhasa city. The strict top-down unified management for ecological environmental protection in plateaus may be an effective method.


Assuntos
Rios , Poluentes Químicos da Água , Agricultura , China , Monitoramento Ambiental/métodos , Nitrogênio/análise , Tibet , Poluentes Químicos da Água/análise , Poluição da Água/análise
15.
Sci Total Environ ; 785: 147380, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33957598

RESUMO

In China, an unambiguous greening trend was observed over the last three decades. The feedback induced by vegetation growth can affect regional climate. Here, we investigated how vegetation feeds back to land surface temperature (LST) in temperature zones and land-use types in China using 18-years (2001-2018) of Moderate Resolution Imaging Spectroradiometer (MODIS) LST and Normalized Difference Vegetation Index (NDVI) data. We first showed that vegetation feedback was significantly negative (p < 0.1, t-test) in most parts of China. Specifically, we discovered a downtrend of vegetation feedback from the coldest temperature zone to the hottest temperature zone. Moreover, vegetation feedback and thermal condition showed an inverse relationship among temperature zones. The inverse relationship clarified that vegetation growth can cool most parts of China during climate change. In the end, we showed the pattern of vegetation feedback among land-use types. Due to the expansion of grassland, vegetation feedback may temporarily positive. Suitable vegetation coverage in urban land, banning deforestation, and cultivating land reasonably can decrease the local temperature by inducing negative vegetation feedback.


Assuntos
Mudança Climática , Imagens de Satélites , China , Retroalimentação , Temperatura
16.
J Hazard Mater ; 407: 124776, 2021 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-33388722

RESUMO

Microplastics (MPs) are pervasive in the environment and have posed growing threat to ecosystems and human health. This study investigated MP abundances in surface water (fresh and salt lakes, urban and rural rivers, etc.) from 28 stations in the Qinghai-Tibet Plateau. MPs were detected in 25 out of 28 water samples with relatively low abundance (average 584.82 particles m-3). Fibers were the most frequently observed shape, particle sizes mostly ranged from 100 to 500 µm, and the greatest number of MPs was polypropylene. Source analysis identified the major sources of domestic wastewater and tourism in some areas. The concentration and proportion of small MPs (20-100 µm) in salty water were apparently greater than that in fresh water, indicating Salt intrusion accelerated MPs fragmentation. As the study area is the origin of the Yangtze River, we further compared the MP distribution throughout the watershed. Nearly two orders of magnitude in MP concentrations were increased associated with urban agglomeration in the middle and downstream areas, but the highest level was marked around the Yichang City (location of the Three Gorges Reservoir) due to interception associated with sedimentation and precipitation. This study provides data and theoretical bases for analyzing MPs migration and degradation processes in high altitudes.

17.
Front Endocrinol (Lausanne) ; 12: 646185, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33967959

RESUMO

Background: To investigate possible mechanisms of postprandial hypertriglyceridemia (PPT), we analyzed serum lipid and apolipoprotein (Apo) AI, B, CII and CIII levels before and after a high-fat meal. Methods: The study has been registered with the China Clinical Trial Registry (registration number:ChiCTR1800019514; URL: http://www.chictr.org.cn/index.aspx). We recruited 143 volunteers with normal fasting triglyceride (TG) levels. All subjects consumed a high-fat test meal. Venous blood samples were obtained during fasting and at 2, 4, and 6 hours after the high-fat meal. PPT was defined as TG ≥2.5 mmol/L any time after the meal. Subjects were divided into two groups according to the high-fat meal test results: postprandial normal triglyceride (PNT) and PPT. We compared the fasting and postprandial lipid and ApoAI, ApoB, ApoCII and ApoCIII levels between the two groups. Results: Significant differences were found between the groups in fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR), TG, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), TG-rich lipoprotein remnants (TRLRs), ApoB, ApoCIII, ApoAI/ApoB and ApoCII/ApoCIII. The insulin, HOMA-IR, TG, TC, LDL-C, non-HDL-C, TRLRs, ApoB, ApoCIII and ApoCII/ApoCIII values were higher in the PPT group, while the ApoAI/ApoB ratio was higher in the PNT group. The postprandial TG level peaked in the PNT group 2 hours after the meal but was significantly higher in the PPT group and peaked at 4 hours. TRLRs gradually increased within 6 hours after the high-fat meal in both groups. The area under the curve (AUC) of TG and TRLRs and the AUC increment were higher in the PPT group (P < 0.001). ApoCIII peaked in the PNT group 2 hours after the meal and gradually decreased. ApoCIII gradually increased in the PPT group within 6 hours after the meal, exhibiting a greater AUC increment (P < 0.001). Fasting ApoCIII was positively correlated with age, systolic and diastolic blood pressure, body mass index (BMI), waist circumference, TC, TG, LDL-C, non-HDL-C, TRLRs, and ApoB (P<0.05). ApoCIII was an independent risk factor of PPT after adjustment for BMI, waist circumference, TC, LDL-C, and ApoB (P < 0.001, OR=1.188). Conclusions: Elevated ApoCIII levels may cause PPT.


Assuntos
Apolipoproteína C-III/sangue , Hipertrigliceridemia/sangue , Período Pós-Prandial , Adulto , Antropometria , Apolipoproteína A-I/sangue , Apolipoproteína C-II/sangue , Apolipoproteínas B/sangue , Índice de Massa Corporal , China , LDL-Colesterol/sangue , Jejum , Feminino , Humanos , Hiperlipidemias , Lipídeos/sangue , Lipoproteínas , Masculino , Pessoa de Meia-Idade , Risco , Triglicerídeos
18.
Chemosphere ; 275: 130099, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33667772

RESUMO

Potentially toxic elements (PTEs) generated from mining activities have affected ecological diversity and ecosystem functions around the world. Accurately assessing the long-term effects of PTEs is critical to classifying recoverable areas and proposing management strategies. Mining activities that shape geographical patterns of biodiversity in individual regions are increasingly understood, but the complex interactions on broad scales and in changing environments are still unclear. In this study, we developed a series of empirical models that simulate the changes in biodiversity and ecosystem functions in mine-affected regions along elevation gradients (1500-3600 m a.s.l) in the metal-rich Qilian Mountains (∼800 km) on the northeastern Tibetan Plateau (China). Our results confirmed the crucial role of PTEs dispersal, topography, and climatic heterogeneity in the diversification of plant community composition. On average, 54% of the changes in ecosystem functions were explained by the interactions among topography, climate, and PTEs. However, merely 30% of the changes were correlated with a single driver. The changes in species composition (explained variables = 94.8%) in the PTE-polluted habitats located in the warm and humid low-elevation deserts and grasslands were greater than those occurring in the dry alpine deserts and grasslands. The ecosystem functions (soil characteristics, nutrient migration, and plant biomass) experienced greater changes in the humid low-elevation grasslands and alpine deserts. Our results suggest that the processes driven by climate or other factors can result in high-altitude PTE-affected habitat facing greater threats.


Assuntos
Mudança Climática , Ecossistema , Altitude , Biodiversidade , China , Tibet
19.
Sci Total Environ ; 739: 140087, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32758955

RESUMO

Microplastics are one of the most valuable indicators reflecting the effects of human activities on natural environment. This study was conducted in a representative remote region of Tibetan Plateau in China, simultaneously analyzing the abundance, compositions and fate of MPs both in water and soil media. MPs were detected in surface water, sediment and soil with abundances ranging from 66.6 to 733.3 number/m3, 20 to 160 items/kg, and 20 to 110 items/kg, respectively. Fibers were the most frequently observed shape in the surface water and sediment, while the dominant shape in the soil was film. The major polymers of MPs in water and soil samples were polypropylene (PP) and polyethylene (PE). Small MPs were the main components with the <500µm fraction accounting for 94.74%, 88.37% and 88.34% of total MP particles in surface water, sediment and soil, respectively. Correlation analysis was further conducted to identify the sources of MPs from different human activities. The night light index was innovatively used to represent population rather than local residents, considering the large number of tourists in this region. It was found that tourism was the main source of MPs in water bodies, while facility agriculture and previous secondary industry are major contributors to soil MPs. A simplified equation set for MP abundance prediction was also formulated related to different industrial features. This study provides an evidence of noticeable MPs associated with human activities even at remote regions, and advances a feasible tool for MPs prediction according to local economic development. CAPSULE: The effect of human activities on natural environment in a remote region was illustrated by evaluating the abundance, compositions and fate of MPs across freshwater and terrestrial environment.

20.
Sci Total Environ ; 742: 140570, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-32721730

RESUMO

Land use and land cover change (LUCC) can alter land surface-atmosphere interactions in the exchange of energy fluxes, with additional consequences on temperature. Understanding the impacts of LUCC on the regional climate contributes to providing fundamental information for future land use planning and regional policy orientation, especially in extremely vulnerable and sensitive plateau regions. This study was designed to explore the regional climate effects associated with LUCC in the Lhasa River basin of Tibetan Plateau using the Weather Research and Forecasting (WRF) model, with a particular focus on near-surface air temperature (Ta) and surface energy fluxes. Two numerical experiments (Case 1980 and Case 2015) were simulated, spanning from November 2014 to November 2015 with the first month as spin-up. The results indicated that the conversion from croplands or grasslands to urban and built-up land led to a noticeable increase in Ta (0.23 °C) during summer. In areas converted from grasslands to waters, Ta decreased by 0.40 °C during spring and approximately 0.50 °C during winter. The afforestation activities at this scale had an obvious impact on the Ta in spring and winter, increasing by 0.20 °C and 0.10 °C, respectively. Generally, the latent heat flux (LE) and sensible heat flux (H) were more sensitive to land conversions, while changes in other fluxes seemed to be weaker. Due to the small change in net radiation (Rn) and ground heat flux (G), the H generally showed an opposite trend with that of LE. Urbanization and reservoir construction resulted in a decrease in the LE, while afforestation construction contributed to an increase in the LE. Our study highlights the impacts of current regional development in the plateau areas on the climate, especially in spring and winter. Urbanization led to a slight warming effect; the cooling effect was more significant in spring and winter than in summer after reservoir construction, and the current afforestation project contributed to a warming effect in winter. This study contributes to the future development of environmentally compatible and sustainable land strategies.

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