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1.
Sci Total Environ ; 929: 172513, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38657798

RESUMO

Balancing water demand for socio-economic development and ecosystem stability presents a challenge for regional sustainable management, especially in drylands. Previous studies have indicated that large-scale ecological restoration projects (ERPs) lead to a decline in terrestrial water storage (TWS) in the Mu Us Sandyland (MUS). However, the effects of other human activities (e.g., cropland reclamation, coal mining) on water resources remain unclear, raising concerns regarding water crisis and human-natural system sustainability. Through the utilization of coal mine location data, we found that the impact of coal mass loss on the Gravity Recovery and Climate Experiment (GRACE) products cannot be ignored in MUS, especially in the coal-rich northeastern part. Combining these data with auxiliary datasets, we observed a significant (p < 0.05) decrease in TWS (-0.85 cm yr-1) and groundwater storage (GWS, -0.95 cm yr-1) in the MUS, with human activities accounting for 79.23 % of TWS and 90.45 % of GWS reductions, primarily due to increased agricultural and industrial water consumption. Agricultural water consumption increased 2.23 times from 2001 to 2020, attributed to enhanced water use intensity (62.6 %) and cropland expansion (37.4 %). Industrial water consumption in Shenmu, a representative coal county, experienced a 4.16-fold rise between 2001 and 2020. Despite these challenges, local governments have alleviated water stress, ensured food security, and increased household income by comprehensive management strategies, such as enhancing water-saving technology and enforcing stringent policies. Previous studies have overestimated the amount of water resources consumed by ERPs. However, ERPs has played a critical role in stabilizing the regional ecological environment and ensuring the region as a vital food and energy supplier. Our findings can guide for socio-economic development and water management policies in similar regions.

2.
Adv Mater ; : e2311591, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38426690

RESUMO

2D van der Waals (vdW) magnets open landmark horizons in the development of innovative spintronic device architectures. However, their fabrication with large scale poses challenges due to high synthesis temperatures (>500 °C) and difficulties in integrating them with standard complementary metal-oxide semiconductor (CMOS) technology on amorphous substrates such as silicon oxide (SiO2 ) and silicon nitride (SiNx ). Here, a seeded growth technique for crystallizing CrTe2 films on amorphous SiNx /Si and SiO2 /Si substrates with a low thermal budget is presented. This fabrication process optimizes large-scale, granular atomic layers on amorphous substrates, yielding a substantial coercivity of 11.5 kilo-oersted, attributed to weak intergranular exchange coupling. Field-driven Néel-type stripe domain dynamics explain the amplified coercivity. Moreover, the granular CrTe2 devices on Si wafers display significantly enhanced magnetoresistance, more than doubling that of single-crystalline counterparts. Current-assisted magnetization switching, enabled by a substantial spin-orbit torque with a large spin Hall angle (85) and spin Hall conductivity (1.02 × 107 ℏ/2e Ω⁻¹ m⁻¹), is also demonstrated. These observations underscore the proficiency in manipulating crystallinity within integrated 2D magnetic films on Si wafers, paving the way for large-scale batch manufacturing of practical magnetoelectronic and spintronic devices, heralding a new era of technological innovation.

3.
Mol Psychiatry ; 28(10): 4056-4069, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37491461

RESUMO

The increasing number of coronavirus disease 2019 (COVID-19) infections have highlighted the long-term consequences of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection called long COVID. Although the concept and definition of long COVID are described differently across countries and institutions, there is general agreement that it affects multiple systems, including the immune, respiratory, cardiovascular, gastrointestinal, neuropsychological, musculoskeletal, and other systems. This review aims to provide a synthesis of published epidemiology, symptoms, and risk factors of long COVID. We also summarize potential pathophysiological mechanisms and biomarkers for precise prevention, early diagnosis, and accurate treatment of long COVID. Furthermore, we suggest evidence-based guidelines for the comprehensive evaluation and management of long COVID, involving treatment, health systems, health finance, public attitudes, and international cooperation, which is proposed to improve the treatment strategies, preventive measures, and public health policy making of long COVID.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Síndrome de COVID-19 Pós-Aguda , Fatores de Risco
4.
Front Public Health ; 10: 810515, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35242732

RESUMO

This study analyzes the conflicting effects of investors' sentiment caused by public health emergencies and uses event analysis methods and linear regressions to examine the impact of such emergencies on the stock prices of insurance companies. The study shows that public health emergencies have a positive and significant impact on insurance companies' portfolios through investors' sentiment, which is persistent. However, the investor fear index triggered by public health emergencies is negatively associated with insurance stock portfolio returns. Meanwhile, insurers with smaller market capitalization are more strongly influenced by investors' sentiment than those with larger market capitalization.


Assuntos
COVID-19 , Saúde Pública , Atitude , Humanos , Seguradoras , Investimentos em Saúde
5.
Biomed Eng Online ; 20(1): 48, 2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34006299

RESUMO

BACKGROUND: Research on the degradation of silk fibroin (SF) scaffolds in vivo lacks uniform and effective standards and experimental evaluation methods. This study aims to evaluate the application of ultrasound in assessing the degradation of SF scaffolds. METHODS: Two groups of three-dimensional regenerated SF scaffolds (3D RSFs) were implanted subcutaneously into the backs of Sprague-Dawley rats. B-mode ultrasound and hematoxylin and eosin (HE) staining were performed on days 3, 7, 14, 28, 56, 84, 112, 140, and 196. The cross-sectional areas for two groups of 3D RSFs that were obtained using these methods were semi-quantitatively analyzed and compared to evaluate the biodegradation of the implanted RSFs. RESULTS: The 3D RSFs in the SF-A group were wholly degraded at the 28th week after implantation. In contrast, the 3D RSFs in the SF-B group were completely degraded at the 16th week. Ultrasonic examination showed that the echoes of 3D RSFs in both groups gradually decreased with the increase of the implantation time. In the early stages of degradation, the echoes of the samples were higher than the echo of the muscle. In the middle of degeneration, the echoes were equal to the echo of the muscle. In the later stage, the echoes of the samples were lower than that of the muscle. The above changes in the SF-B group were earlier than those in the SF-A group. Semi-quantitative analysis of the cross-sectional areas detected using B-mode ultrasound revealed that the degradations of the two 3D RSF groups were significantly different. The degradation rate of the SF-B group was found to be higher than that of the SF-A group. This was consistent with the semi-quantitative detection results for HE staining. Regression analysis showed that the results of the B-mode ultrasound and HE staining were correlated in both groups, indicating that B-mode ultrasound is a reliable method to evaluate the SF scaffold degradation in vivo. CONCLUSIONS: This study suggests that B-mode ultrasound can clearly display the implanted SF scaffolds non-invasively and monitor the degradation of the different SF scaffolds after implantation in living organisms in real-time.


Assuntos
Fibroínas , Animais , Materiais Biocompatíveis , Ratos , Engenharia Tecidual , Alicerces Teciduais
6.
Sensors (Basel) ; 20(2)2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31936175

RESUMO

Wearable indoor localization can now find applications in a wide spectrum of fields, including the care of children and the elderly, sports motion analysis, rehabilitation medicine, robotics navigation, etc. Conventional inertial measurement unit (IMU)-based position estimation and radio signal indoor localization methods based on WiFi, Bluetooth, ultra-wide band (UWB), and radio frequency identification (RFID) all have their limitations regarding cost, accuracy, or usability, and a combination of the techniques has been considered a promising way to improve the accuracy. This investigation aims to provide a cost-effective wearable sensing solution with data fusion algorithms for indoor localization and real-time motion analysis. The main contributions of this investigation are: (1) the design of a wireless, battery-powered, and light-weight wearable sensing device integrating a low-cost UWB module-DWM1000 and micro-electromechanical system (MEMS) IMU-MPU9250 for synchronized measurement; (2) the implementation of a Mahony complementary filter for noise cancellation and attitude calculation, and quaternions for frame rotation to obtain the continuous attitude for displacement estimation; (3) the development of a data fusion model integrating the IMU and UWB data to enhance the measurement accuracy using Kalman-filter-based time-domain iterative compensations; and (4) evaluation of the developed sensor module by comparing it with UWB- and IMU-only solutions. The test results demonstrate that the average error of the integrated module reached 7.58 cm for an arbitrary walking path, which outperformed the IMU- and UWB-only localization solutions. The module could recognize lateral roll rotations during normal walking, which could be potentially used for abnormal gait recognition.


Assuntos
Análise Custo-Benefício/economia , Movimento (Física) , Dispositivos Eletrônicos Vestíveis/economia , Aceleração , Acústica , Marcha/fisiologia , Humanos , Ondas de Rádio , Reprodutibilidade dos Testes , Processamento de Sinais Assistido por Computador , Caminhada , Tecnologia sem Fio
7.
Lancet ; 390(10107): 2050-2062, 2017 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-28864332

RESUMO

BACKGROUND: The relationship between macronutrients and cardiovascular disease and mortality is controversial. Most available data are from European and North American populations where nutrition excess is more likely, so their applicability to other populations is unclear. METHODS: The Prospective Urban Rural Epidemiology (PURE) study is a large, epidemiological cohort study of individuals aged 35-70 years (enrolled between Jan 1, 2003, and March 31, 2013) in 18 countries with a median follow-up of 7·4 years (IQR 5·3-9·3). Dietary intake of 135 335 individuals was recorded using validated food frequency questionnaires. The primary outcomes were total mortality and major cardiovascular events (fatal cardiovascular disease, non-fatal myocardial infarction, stroke, and heart failure). Secondary outcomes were all myocardial infarctions, stroke, cardiovascular disease mortality, and non-cardiovascular disease mortality. Participants were categorised into quintiles of nutrient intake (carbohydrate, fats, and protein) based on percentage of energy provided by nutrients. We assessed the associations between consumption of carbohydrate, total fat, and each type of fat with cardiovascular disease and total mortality. We calculated hazard ratios (HRs) using a multivariable Cox frailty model with random intercepts to account for centre clustering. FINDINGS: During follow-up, we documented 5796 deaths and 4784 major cardiovascular disease events. Higher carbohydrate intake was associated with an increased risk of total mortality (highest [quintile 5] vs lowest quintile [quintile 1] category, HR 1·28 [95% CI 1·12-1·46], ptrend=0·0001) but not with the risk of cardiovascular disease or cardiovascular disease mortality. Intake of total fat and each type of fat was associated with lower risk of total mortality (quintile 5 vs quintile 1, total fat: HR 0·77 [95% CI 0·67-0·87], ptrend<0·0001; saturated fat, HR 0·86 [0·76-0·99], ptrend=0·0088; monounsaturated fat: HR 0·81 [0·71-0·92], ptrend<0·0001; and polyunsaturated fat: HR 0·80 [0·71-0·89], ptrend<0·0001). Higher saturated fat intake was associated with lower risk of stroke (quintile 5 vs quintile 1, HR 0·79 [95% CI 0·64-0·98], ptrend=0·0498). Total fat and saturated and unsaturated fats were not significantly associated with risk of myocardial infarction or cardiovascular disease mortality. INTERPRETATION: High carbohydrate intake was associated with higher risk of total mortality, whereas total fat and individual types of fat were related to lower total mortality. Total fat and types of fat were not associated with cardiovascular disease, myocardial infarction, or cardiovascular disease mortality, whereas saturated fat had an inverse association with stroke. Global dietary guidelines should be reconsidered in light of these findings. FUNDING: Full funding sources listed at the end of the paper (see Acknowledgments).


Assuntos
Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/mortalidade , Causas de Morte , Carboidratos da Dieta/efeitos adversos , Gorduras na Dieta/efeitos adversos , Adulto , Idoso , Doenças Cardiovasculares/fisiopatologia , Estudos de Coortes , Países Desenvolvidos/economia , Países em Desenvolvimento/economia , Dieta/efeitos adversos , Metabolismo Energético , Feminino , Humanos , Renda , Internacionalidade , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Medição de Risco , Análise de Sobrevida
8.
Small ; 11(37): 4970-5, 2015 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-26153225

RESUMO

Herein, for the first time, we presented a simple and general approach by using personal glucose meters (PGM) for portable and ultrasensitive detection of microbial pathogens. Upon addition of pathogenic bacteria, glucoamylase-quaternized magnetic nanoparticles (GA-QMNPS) conjugates were disrupted by the competitive multivalent interactions between bacteria and QMNPS, resulting in the release of GA. After magnetic separation, the free GA could catalyze the hydrolysis of amylose into glucose for quantitative readout by PGM. In such way, PGM was transmuted into a bacterial detection device and extremely low detection limits down to 20 cells mL(-1) was achieved. More importantly, QMNPS could inhibit the growth of the bacteria and destroy its cellular structure, which enabled bacteria detection and inhibition simultaneously. The simplicity, portability, sensitivity and low cost of presented work make it attractive for clinical applications.


Assuntos
Técnicas Bacteriológicas/instrumentação , Técnicas Bacteriológicas/métodos , Automonitorização da Glicemia/instrumentação , Escherichia coli/isolamento & purificação , Staphylococcus aureus/isolamento & purificação , Técnicas Bacteriológicas/economia , Automonitorização da Glicemia/economia , Escherichia coli/ultraestrutura , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/ultraestrutura , Viabilidade Microbiana , Staphylococcus aureus/ultraestrutura
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