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1.
Environ Sci Technol ; 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39137304

RESUMEN

As the largest iron and steel producer, China still cannot meet its demand of iron and steel only through domestic primary supply in the last few decades. Hence, secondary iron resources are increasingly significant in meeting China's iron supply and demand balance. However, the secondary iron resource availability in China and how it impacts the future supply demand balance were still insufficiently discussed. In this work, we developed a material flow analysis and secondary resources reserve assessment (MFA-SRRA) integrated model, assessed secondary iron resources availability, and conducted a supply demand analysis through nine scenarios for irons in China. The results showed that China's secondary iron reserves will increase from 8.9 Gt in 2021 to 14.04 to 19.01 Gt in 2050. With the increasing secondary iron supply, more than 60% of iron ore as a source of steelmaking can be replaced by 2050. Landfills, as a significant reserve of iron but always ignored, will accumulate 1.42-1.51 Gt secondary iron resources by 2050 and should be noticed to be mined and utilized in the future. Last, we suggest that promoting innovation in landfill mining technology and making sustainable material management policies are urgent to prevent these secondary iron resources from becoming real waste.

2.
Environ Sci Technol ; 58(11): 5014-5023, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38437169

RESUMEN

Estimates of the land area occupied by wind energy differ by orders of magnitude due to data scarcity and inconsistent methodology. We developed a method that combines machine learning-based imagery analysis and geographic information systems and examined the land area of 318 wind farms (15,871 turbines) in the U.S. portion of the Western Interconnection. We found that prior land use and human modification in the project area are critical for land-use efficiency and land transformation of wind projects. Projects developed in areas with little human modification have a land-use efficiency of 63.8 ± 8.9 W/m2 (mean ±95% confidence interval) and a land transformation of 0.24 ± 0.07 m2/MWh, while values for projects in areas with high human modification are 447 ± 49.4 W/m2 and 0.05 ± 0.01 m2/MWh, respectively. We show that land resources for wind can be quantified consistently with our replicable method, a method that obviates >99% of the workload using machine learning. To quantify the peripheral impact of a turbine, buffered geometry can be used as a proxy for measuring land resources and metrics when a large enough impact radius is assumed (e.g., >4 times the rotor diameter). Our analysis provides a necessary first step toward regionalized impact assessment and improved comparisons of energy alternatives.


Asunto(s)
Fuentes Generadoras de Energía , Viento , Humanos , Granjas , Fenómenos Físicos
3.
Environ Sci Technol ; 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39150153

RESUMEN

Recent years have witnessed increasing attempts to track trade flows of critical materials across world regions and along the life cycle for renewable energy and the low carbon transition. Previous studies often had limited spatiotemporal coverage, excluded end-use products, and modeled different life cycle stages as single-layer networks. Here, we integrated material flow analysis and complex network analysis into a multilayer framework to characterize the spatiotemporal and multilayer trade network patterns of the global cobalt cycle from 1988 to 2020. We found substantial growth and notable structural changes in global cobalt trade over the past 30 years. China, Germany, and the United States play pivotal roles in different layers and stages of the global cobalt cycle. The interlayer relationships among alloys, batteries, and materials are robust and continually strengthening, indicating a trend toward synergistic trade. However, cobalt ore-exporting countries are highly concentrated and rarely involved in later life cycle stages, resulting in the weakest relationship between the ore layer and other layers. This causes fluctuations and uncertainty in the global cobalt trade. Our model, linking industrial ecology, supply chain analysis, and network analysis, can be extended to other materials that are critical for the future green transition.

4.
Artículo en Inglés | MEDLINE | ID: mdl-38708780

RESUMEN

BACKGROUND: Large to giant congenital melanocytic nevi (LGCMN) significantly decrease patients' quality of life, but the inaccuracy of current classification system makes their clinical management challenging. OBJECTIVES: To improve and extend the existing LGCMN 6B/7B classification systems by developing a novel LGCMN classification system based on a new phenotypic approach to clinical tool development. METHODS: Three hundred and sixty-one LGCMN cases were categorized into four subtypes based on anatomic site: bonce (25.48%), extremity (17.73%), shawl (19.67%) and trunks (37.12%) LGCMN. A 'BEST' classification system of LGCMN was established and validated by a support vector machine classifier combined with the 7B system. RESULTS: The most common LGCMN distributions were on bonce and trunks (bathing trunk), whereas breast/belly and body LGCMN were exceptionally rare. Sexual dimorphism characterized distribution, with females showing a wider range of lesions in the genital area. Nearly half of the patients with bathing trunk LGCMN exhibited a butterfly-like distribution. Approximately half of the LGCMN with chest involvement did not have nipple-areola complex involvement. Abdomen, back and buttock involvement was associated with the presence of satellite nevi (r = 0.558), and back and buttock involvement was associated with the presence of nodules (r = 0.364). CONCLUSIONS: The effective quantification of a standardized anatomical site provides data support for the accuracy of the 6B/7B classification systems. The simplified BEST classification system can help establish a LGCMN clinical database for exploration of LGCMN aetiology, disease management and prognosis prediction.

5.
Aesthetic Plast Surg ; 48(2): 213-220, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37957391

RESUMEN

BACKGROUND: Tear trough deformity makes patients appear tired. Patients with less severe tear trough deformity prefer a less invasive method to correct the deformity. The infraorbital area is a multilayered tissue, and the aging of various components leads to tear trough deformity. To this end, we utilized the different characteristics of different fat derivatives to correct tear trough deformity. METHODS: Thirty-two patients with Barton Grade I/II tear trough deformity were enrolled in this study between September 2020 and March 2021. We injected Stromal Vascular Fraction Gel (SVF-Gel) into the suborbicularis oculi fat layer and Nanofat into the subcutaneous. After 12 months of follow-up, we evaluated the changes using standardized clinical photogrammetric techniques, volume, global aesthetic improvement scale, and patient self-evaluation. RESULTS: There were no major complications in any of the 32 patients. The measured data points demonstrated improvements in all aesthetic parameters. The width of the tear trough and the distance from the pupil to the tear trough improved. The Global Aesthetic Improvement Scale (GAIS) showed a high score (2.45±0.64 points), with patient self-assessment showing satisfactory results. CONCLUSION: SVF-Gel combined with Nanofat injection can effectively correct tear trough deformities. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Asunto(s)
Tejido Adiposo , Fracción Vascular Estromal , Humanos , Inyecciones
6.
J Environ Manage ; 363: 121314, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38843731

RESUMEN

Pretreatment, the initial step in recycling spent lithium-ion batteries (LIBs), efficiently separates cathode and anode materials to facilitate key element recovery. Despite brief introductions in existing research, a comprehensive evaluation and comparison of processing methods is lacking. This study reviews 346 references on LIBs recycling, analyzing pretreatment stages, treatment conditions, and method effects. Our analysis highlights insufficient attention to discharge voltage safety and environmental impact. Mechanical disassembly, while suitable for industrial production, overlooks electrolyte recovery and complicates LIBs separation. High temperature pyrolysis flotation offers efficient separation of mixed electrode materials, enhancing mineral recovery. We propose four primary pretreatment processes: discharge, electrolyte recovery, crushing and separation, and electrode material recovery, offering simplified, efficient, green, low-cost, and high-purity raw materials for subsequent recovery processes.


Asunto(s)
Suministros de Energía Eléctrica , Litio , Reciclaje , Litio/química , Reciclaje/métodos , Electrodos , Iones
7.
J Am Chem Soc ; 145(19): 10576-10583, 2023 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-37130260

RESUMEN

Li and Na metals with high energy density are promising in application in rechargeable batteries but suffer from degradation in the ambient atmosphere. The phenomenon that in terms of kinetics, Li is stable but Na is unstable in dry air has not been fully understood. Here, we use in situ environmental transmission electron microscopy combined with theoretical simulations and reveal that the different stabilities in dry air for Li and Na are reflected by the formation of compact Li2O layers on Li metal, while porous and rough Na2O/Na2O2 layers on Na metal are a consequence of the different thermodynamic and kinetics in O2. It is shown that a preformed carbonate layer can change the kinetics of Na toward an anticorrosive behavior. Our study provides a deeper understanding of the often-overlooked chemical reactions with environmental gases and enhances the electrochemical performance of Li and Na by controlling interfacial stability.

8.
Rev Cardiovasc Med ; 24(8): 243, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39076697

RESUMEN

Background: Transcatheter aortic valve replacement (TAVR) is an effective alternative treatment for patients with aortic stenosis (AS) who have intermediate to high surgical risk or who are inoperable. However, the incidence of conduction abnormalities is high after TAVR, which can reduce the effectiveness of the surgery. Our research objective is to explore the risk factors of new-onset conduction abnormalities after TAVR, providing reference value for clinical doctors to better prevent and treat conduction abnormalities. Methods: Patients who underwent TAVR were divided into those who developed heart block and those who did not. Baseline clinical characteristics, cardiac structural parameters, procedural characteristics, electrocardiogram (ECG) changes before and after TAVR ( △ = postoperative minus preoperative), and surgical complications were compared. Logistic regression was applied to identify significant risk factors for new-onset heart block. Results: We studied 93 patients, of whom 34.4% developed heart blocks. Univariate logistic regression showed that prior history of malignancy, atrial fibrillation, preoperative high-level total cholesterol and low-density lipoprotein cholesterol (LDL-C), △ HR, △ QRS interval, △ QT interval, and △ QTc interval were risk factors of new-onset heart block after TAVR. Multivariate analysis showed that preoperative high-level LDL-C and △ QRS interval remained significant independent risk factors after adjusting for potential confounds. Conclusions: Heart block is the most common complication of TAVR, and its significant independent risk factors include high-level LDL-C and △ QRS interval.

9.
Br J Clin Pharmacol ; 89(2): 874-886, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36098470

RESUMEN

To evaluate the pharmacokinetic effects of SHR3680 on repaglinide and bupropion and its metabolite hydroxybupropion. METHODS: A single-centre, open-label, single-arm, fixed-sequence clinical trial in 18 patients with prostate cancer. RESULTS: After a single oral dose of 0.5 mg repaglinide and SHR3680, geometric mean peak plasma concentration (Cmax ) of plasma repaglinide was 14.240 and 5.887 ng/mL, geometric mean area under the concentration-time curve (AUC0-t )was 20.577 and 7.320 h ng/mL, geometric mean AUC0-∞ was 20.949 and 7.451 h ng/mL, mean half-life (t1/2 ) was 1.629 and 1.195 hours, and geometric mean oral clearance (CL/F) was 23.867 and 67.107 L/h, respectively. After a single oral administration of 150 mg bupropion and SHR3680, geometric mean Cmax of plasma bupropion was 85.430 and 33.747 ng/mL, geometric mean AUC0-t was 1003.896 and 380.158 h ng/mL, geometric mean AUC0-∞ was 1038.054 and 401.387 h ng/mL, mean t1/2 was 22.533 and 17.733 hours, and geometric mean CL/F was 144.501 and 373.705 L/h, respectively. The plasma geometric mean Cmax of its main active metabolic hydroxybupropion was 268.113 and 177.318 ng/mL, geometric mean AUC0-t was 14 283.087 and 5420.219 h ng/mL, geometric mean AUC0-∞ was 15 218.158 and 5364.625 h ng/mL, mean t1/2 were 36.069 and 16.688 hours, and geometric mean CL/F was 8.623 L/h and 27.961 L/h, respectively. CONCLUSION: Coadministration of SHR3680 with repaglinide or bupropion significantly shortened the elimination half-lives, significantly increased the apparent clearance rate, and significantly decreased the in vivo exposure of repaglinide, bupropion and hydroxybupropion compared with single administration of repaglinide or bupropion.


Asunto(s)
Bupropión , Neoplasias de la Próstata , Humanos , Masculino , Área Bajo la Curva , Carbamatos/farmacocinética , Estudios Cruzados
10.
Environ Sci Technol ; 57(38): 14113-14126, 2023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37709662

RESUMEN

Some key low-carbon technologies, ranging from wind turbines to electric vehicles, are underpinned by the strong rare-earth-based permanent magnets of the Nd, Pr (Dy)-Fe-Nb type (NdFeB). These NdFeB magnets, which are sensitive to demagnetization with temperature elevation (the Curie point), require the addition of variable amounts of dysprosium (Dy), where an elevation of the Curie point is needed to meet operational conditions. Given that China is the world's largest REE supplier with abundant REE reserves, the impact of an ambitious 1.5 °C climate target on China's Dy supply chain has sparked widespread concern. Here, we explore future trends and innovation strategies associated with the linkage between Dy and NdFeBs under various climate scenarios in China. We find China alone is expected to exhaust the global present Dy reserve within the next 2-3 decades to facilitate the 1.5 °C climate target. By implementing global available innovation strategies, such as material substitution, reduction, and recycling, it is possible to avoid 48%-68% of China's cumulative demand for Dy. Nevertheless, ongoing efforts in REE exploration and production are still required to meet China's growing Dy demand, which will face competition from the United States, European Union, and other countries with ambitious climate targets. Thus, our analysis urges China and those nations to form wider cooperation in REE supply chains as well as in NdFeB innovation for the realization of a global climate-safe future.


Asunto(s)
Disprosio , Metales de Tierras Raras , Clima , Imanes , China
11.
BMC Cardiovasc Disord ; 23(1): 34, 2023 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-36653770

RESUMEN

BACKGROUND: Impaired left ventricular function is an independent predictor of adverse clinical outcomes in patients with aortic stenosis. The aim of this study is to evaluate the short-term changes of echocardiographic parameters, New York Heart Association (NYHA) class and B-type natriuretic peptide (BNP) level and adverse events amongst patients with heart failure (HF) after transcatheter aortic valve replacement (TAVR) procedure. METHODS: This was a retrospective cohort study conducted at affiliated Yantai Yuhuangding Hospital of Qingdao University between September 2017 and September 2022. TAVR cases were stratified into three groups [heart failure with reduced ejection fraction (HFrEF), heart failure with mildly reduced ejection fraction (HFmrEF), heart failure with preserved ejection fraction (HFpEF)] by left ventricular ejection fraction (LVEF). Baseline characteristics, changes in echocardiographic parameters (1 week and 1 month), BNP (1 month), and NYHA class (6 months) post-TAVR were compared across the three groups. Meanwhile, we observed the adverse events of the patients after TAVR. RESULTS: A total of 96 patients were included, of whom 15 (15.6%) had HFrEF, 15 (15.6%) had HFmrEF, and 66 (68.8%) had HFpEF. Compared to the HFpEF subgroup, patients in the HFrEF subgroup were younger (p < 0.05), and with a higher BNP (p < 0.05). The left ventricular end-diastolic dimension (LVEDD) in HFrEF group decreased significantly after TAVR. HFmrEF and HFrEF patients showed significant improvements in LVEF after TAVR. The pulmonary artery systolic pressure (PASP), aortic valve peak gradient (AVPG) and aortic valve peak gradient (Vmax) decreased significantly 1 month after TAVR in all three groups compared to the baseline (all p < 0.05). BNP significantly reduced in HFrEF group compared to HFpEF patients after TAVR (p < 0.05). The majority of patients experienced an improvement at least one NYHA class in all three groups 6 months post-TAVR. There is no significant increase in the risk of adverse events in the HFrEF group. CONCLUSIONS: Patients who underwent TAVR achieved significant improvements in BNP, NYHA class, LVEDD, LVEF, and PASP across the three HF classes, with a more rapid and pronounced improvement in the HFrEF and HFmrEF groups. Complication rates were low in the different HF groups. There is no significant increase in the risk of periprocedural complications in the HFrEF and HFmrEF groups.


Asunto(s)
Estenosis de la Válvula Aórtica , Insuficiencia Cardíaca , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Anciano , Función Ventricular Izquierda , Volumen Sistólico , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/terapia , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Pronóstico , Estudios Retrospectivos , Estenosis de la Válvula Aórtica/complicaciones , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/cirugía , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía
12.
J Sci Food Agric ; 103(8): 3766-3775, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36222712

RESUMEN

BACKGROUND: The market demand for Panax notoginseng (P. notoginseng) is growing rapidly because of its useful properties in food and medicine. However, the frequent adulteration of P. notoginseng seriously affects the health of consumers and is a great challenge to food safety. In this study, low- and high-field nuclear magnetic resonance (LF/HF-NMR) were applied to detect the transverse relaxation distribution of P. notoginseng contaminated with different ratios of Caulis clematidis armandii (CCA) and the components in P. notoginseng and CCA, respectively. RESULTS: Fifty-seven kinds of major and minor components in P. notoginseng and CCA were identified and quantified from their high-resolution NMR spectra, and there were significant differences in ginsenosides, sucrose, and glucose between P. notoginseng and CCA. Furthermore, the partial least squares regression analysis results indicated that LF-NMR parameters (T21 and S21 ) changed linearly as the ratio of CCA increased, and these changes were attributed to the variations in polysaccharide and sucrose in adulterated P. notoginseng. CONCLUSION: In the relaxation time-based pattern recognition models, the authentic P. notoginseng powder could be classified with 100% accuracy from adulterated P. notoginseng when the adulteration ratio was greater than 30%, demonstrating the possibility of LF-NMR, in combination with pattern recognition, for rapid discrimination of food authenticity. © 2022 Society of Chemical Industry.


Asunto(s)
Ginsenósidos , Panax notoginseng , Panax , Ginsenósidos/análisis , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Panax/química , Panax notoginseng/química , Polvos , Sacarosa
13.
Expert Syst Appl ; 213: 118841, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36157791

RESUMEN

The outbreak of COVID-19 brings almost the biggest explosions of scientific literature ever. Facing such volume literature, it is hard for researches to find desired citation when carrying out COVID-19 related research, especially for junior researchers. This paper presents a novel neural network based method, called citation relational BERT with heterogeneous deep graph convolutional network (CRB-HDGCN), for COVID-19 inline citation recommendation task. The CRB-HDGCN contains two main stages. The first stage is to enhance the representation learning of BERT model for COVID-19 inline citation recommendation task through CRB. To achieve the above goal, an augmented citation sentence corpus, which replaces the citation placeholder with the title of the cited papers, is used to lightly retrain BERT model. In addition, we extract three types of sentence pair according citation relation, and establish sentence prediction tasks to further fine-tune the BERT model. The second stage is to learn effective dense vector of nodes among COVID-19 bibliographic graph through HDGCN. The HDGCN contains four layers which are essentially all sub neural networks. The first layer is initial embedding layer which generates initial input vectors with fixed size through CRB and a multilayer perceptron. The second layer is a heterogeneous graph convolutional layer. In this layer, we expand traditional homogeneous graph convolutional network into heterogeneous by subtly adding heterogeneous nodes and relations. The third layer is a deep attention layer. This layer uses trainable project vectors to reweight the node importance simultaneously according to both node types and convolution layers, which further promotes the performance of learnt node vectors. The last decoder layer recovers the graph structure and let the whole network trainable. The recommendation is finally achieved by integrating the high performance heterogeneous vectors learnt from CRB-HDGCN with the query vectors. We conduct experiments on the CORD-19 and LitCovid datasets. The results show that compared with the second best method CO-Search, CRB-HDGCN improves MAP, MRR, P@100 and R@100 with 21.8%, 22.7%, 37.6% and 21.2% on CORD-19, and 29.1%, 25.9%, 15.3% and 11.3% on LitCovid, respectively.

14.
J Med Virol ; 94(12): 6016-6022, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35922376

RESUMEN

The seroprevalence of Kaposi's sarcoma-associated herpesvirus (KSHV) is high in Xinjiang, China. But the seroprevalence of KSHV and risk factors are still unknown in Gansu which is adjacent to Xinjiang. Six hundred and seventy-eight serum samples of the general population and 87 serum samples of syphilis patients from Jiuquan, Gansu were tested for antibodies against KSHV, including one latent protein (ORF73) and two lytic proteins (ORF65 and K8.1) using the ELISA. The total KSHV-seropositive rate was 15.9% in 678 serum samples in the Jiuquan area, and the KSHV-seropositive rate of males was higher than females (18.0% vs. 14.6%, p > 0.05). The Uygur, Kazakh, Hui, Manchu, and Mongolian populations had a higher seroprevalence of KSHV than the Han population (43.8%, 40.0%, 34.5%, 30.3%, 35.0% vs. 11.0%, respectively) among the ethnic groups in Jiuquan. Compared to the Han, Uygur, Kazak, Hui, Manchu, and Mongolian people had an increase in the risk of KSHV of 528.9%, 439.1%, 325.6%, 251.6%, and 335.4% (p < 0.001, p < 0.001, p < 0.001, p = 0.002, p = 0.003, respectively). The serum prevalence of KSHV in subjects aged < 20 years, 20-50 years, and >50 years was 13.8%, 14.7%, and 20.1%, respectively. Compared to the subjects aged < 20 years, 20-50 years and >50 years had an increase in the risk of KSHV of 7.4% and 56.9% (p = 0.829 and p = 0.204, respectively). Compared to the positive rate of KSHV in the general population of Anhui, the positive rate of KSHV was significantly higher in the general population of the Jiuquan area (15.9% vs. 9%, p < 0.01). There was no significant difference in the positive rate of KSHV between the Han population of Jiuquan and the Han population of Anhui (p > 0.05). In the population of syphilis patients in the Jiuquan area, the positive rate of KSHV was 30.7%, which was higher than that of the general population in the Gansu area (p < 0.05). This study indicates that Gansu has a high seroprevalence of KSHV. Ethnicity and syphilis are risk factors for KSHV infection.


Asunto(s)
Herpesvirus Humano 8 , Sarcoma de Kaposi , Sífilis , Anticuerpos Antivirales , China/epidemiología , Femenino , Humanos , Masculino , Factores de Riesgo , Estudios Seroepidemiológicos
15.
Langmuir ; 38(48): 14712-14724, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36420594

RESUMEN

A chitosan layer was covalently bonded to a polyetheretherketone (PEEK) surface using a simple facile self-assembly method to address inadequate biological activity and infection around the implant. The surface characterization, layer degradation, biological activity, and antibacterial adhesion properties of chitosan-modified PEEK (PEEK-CS) were studied. Through chitosan grafting, the surface morphology changed, the surface roughness increased, and the contact angle decreased significantly. PEEK-CS boosted cell adhesion, proliferation, increased alkaline phosphate activity, extracellular matrix mineralization, and expression of osteogenic genes. PEEK-CS demonstrated less adhesion to Porphyromonas gingivalis as well as less bacterial adhesion to P. gingivalis and Streptococcus mutans. According to our findings, chitosan modification significantly improved the osteogenic ability and antibacterial adhesion of PEEK in vitro.


Asunto(s)
Quitosano , Quitosano/farmacología , Polímeros/farmacología , Cetonas/farmacología , Polietilenglicoles/farmacología , Osteogénesis , Antibacterianos/farmacología , Propiedades de Superficie
16.
Environ Sci Technol ; 56(6): 3821-3829, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-35201765

RESUMEN

Life cycle assessment plays a critical role in quantifying environmental impacts, but its credibility remains challenged when data and uncertainty analysis are lacking. In this study, we propose a data compilation framework to address these two issues. The framework first quantifies the correlations of production activities among existing data in temporal, geographical, and taxonomic dimensions. The framework then introduces covariance functions to convert these correlations to a similarity matrix, and the Gaussian process regression model is adopted to predict new data based on these covariance functions. The associated uncertainty is automatically characterized using the posterior distribution of predictions. The framework is demonstrated on the nitrogen fertilizer application rate for food production─an activity recognized for its environmental burden─with results capable of reflecting temporal and geographical variations. By introducing the concept of phylogenetic distance as a correlation of taxonomy, the framework provides a quantitative basis for predictions in a proxy data usage scenario. The framework can be used in developing temporally and regionally representative life cycle inventories and databases and can facilitate consistent uncertainty quantification in future life cycle assessment methodologies.


Asunto(s)
Ambiente , Nitrógeno , Animales , Estadios del Ciclo de Vida , Filogenia , Incertidumbre
17.
Environ Sci Technol ; 56(16): 11807-11817, 2022 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-35920659

RESUMEN

Neodymium (Nd), an essential type of rare earth element, has attracted increasing attention in recent years due to its significant role in emerging technologies and its globally imbalanced demand and supply. Understanding the global and regional Nd stocks and flows would thus be important for understanding and mitigating potential supply risks. In this work, we applied a trade-linked multiregional material flow analysis to map the global and regional neodymium cycles from 1990 to 2020. We reveal increasingly complex trade patterns of Nd-containing products and a clearly dominant but slightly weakening role of China in the global Nd trade (for both raw materials and semi- and final products) along the life cycle in the last 30 years. A total of 880 kt Nd was mined accumulatively and flowed into the global socioeconomic system, mainly as NdFeB permanent magnets (79%) in semi-products and conventional vehicles and home appliances (together 48%) in final products. Approximately 64% (i.e., 563 kt Nd) of all the mined Nd globally were not recycled, indicating a largely untapped potential of recycling in securing Nd supply and an urgency to overcome the present technological and non-technical challenges. The global Nd cycle in the past three decades is characterized by different but complementary roles of different regions along the global Nd value chain: China dominates in the provision of raw materials and semi- and final products, Japan focuses on the manufacturing of magnets and electronics, and the United States and European Union show advantages in the vehicle industry. Anticipating increasing demand of Nd in emerging energy and transport technologies in the future, more coordinated efforts among different regions and increased recycling are urgently needed for ensuring both regional and global Nd supply and demand balance and a common green future.


Asunto(s)
Metales de Tierras Raras , Neodimio , Imanes , Reciclaje , Tecnología
18.
Int J Mol Sci ; 23(17)2022 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-36077309

RESUMEN

BACKGROUND: Mechanically gated PIEZO channels lead to an influx of cations, activation of additional Ca2+ channels, and cell depolarization. This study aimed to investigate PIEZO2's role in breast cancer. METHODS: The clinical relevance of PIEZO2 expression in breast cancer patient was analyzed in a publicly available dataset. Utilizing PIEZO2 overexpressed breast cancer cells, and in vitro and in vivo experiments were conducted. RESULTS: High expression of PIEZO2 was correlated with a worse survival in triple-negative breast cancer (TNBC) but not in other subtypes. Increased PEIZO2 channel function was confirmed in PIEZO2 overexpressed cells after mechanical stimulation. PIEZO2 overexpressed cells showed increased motility and invasive phenotypes as well as higher expression of SNAIL and Vimentin and lower expression of E-cadherin in TNBC cells. Correspondingly, high expression of PIEZO2 was correlated with the increased expression of epithelial-mesenchymal transition (EMT)-related genes in a TNBC patient. Activated Akt signaling was observed in PIEZO2 overexpressed TNBC cells. PIEZO2 overexpressed MDA-MB-231 cells formed a significantly higher number of lung metastases after orthotopic implantation. CONCLUSION: PIEZO2 activation led to enhanced SNAIL stabilization through Akt activation. It enhanced Vimentin and repressed E-cadherin transcription, resulting in increased metastatic potential and poor clinical outcomes in TNBC patients.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Cadherinas/genética , Cadherinas/metabolismo , Línea Celular Tumoral , Movimiento Celular/genética , Transición Epitelial-Mesenquimal/genética , Humanos , Canales Iónicos/genética , Fenotipo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Neoplasias de la Mama Triple Negativas/patología , Vimentina/genética , Vimentina/metabolismo
19.
J Environ Manage ; 318: 115599, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-35780676

RESUMEN

Owing to its key role in high-tech industry and clean energy technology, cobalt has been regarded as a critical material in many countries. In this paper, material flow analysis was used to quantitatively track cobalt material flows in China throughout the entire life cycle from 2000 to 2021. Based on data pertaining to cobalt commodity trade, cobalt loss during raw material processing, and recovered cobalt, we analysed the actual cobalt consumption in China. During the study period from 2000 to 2021, the main findings were as follows: (1) China's cobalt raw material imports accounted for 84.7% of the total raw materials acquired, while the export of cobalt-containing end products amounted to 32.6% of the total production. (2) China's cumulative net import of all cobalt commodities reached 561 kt, and battery products accounted for 73.3% of the total cobalt consumption. (3) China recovered 77 kt of cobalt from end-of-life products, while 327 kt of cobalt was not recovered. (4) The cumulative cobalt loss during raw material processing reached 288 kt, with the highest loss occurring in refining (51.0%), followed by manufacturing and fabrication (26.5%), beneficiation (12.3%), and ore mining (10.2%). The overall utilization efficiency of cobalt was 73.8% throughout the entire life cycle. (5) China's actual cobalt consumption reached 497 kt, accounting for 51.9% of the apparent cobalt consumption. Moreover, 61.1% of the cobalt products produced in China was consumed domestically, while 38.9% was exported. The massive export of cobalt commodities resulted in China bearing a disproportionate responsibility for carbon emission reduction. The research results can provide a scientific reference for the reasonable adjustment of the trade structure of cobalt commodities and realization of the economic and efficient utilization of cobalt resources in China.


Asunto(s)
Cobalto , Industrias , Animales , Carbono , China , Comercio , Estadios del Ciclo de Vida
20.
Pharm Biol ; 60(1): 1169-1176, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35701112

RESUMEN

CONTEXT: S-Propargyl-cysteine (SPRC), an endogenous H2S modulator, exerts anti-inflammatory effects on cardiovascular and neurodegenerative disease, but it remains unknown whether SPRC can prevent autoimmune hepatitis. OBJECTIVE: To evaluate the preventive effect of SPRC on concanavalin A (Con A)-induced liver injury and uncover the underlying mechanisms. MATERIALS AND METHODS: Mice were randomly divided into five groups: control, Con A, SPRC (5 and 10 mg/kg injected intravenously once a day for 7 days), and propargylglycine (PAG; 50 mg/kg injected intraperitoneally 0.5 h before SPRC for 7 days). All mice except the controls were intravenously injected with Con A (20 mg/kg) on day 7. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were evaluated using kits. Inflammatory cytokines (TNF-α and IFN-γ) in the blood and in the liver were detected by ELISA Kit and real-time PCR, respectively. The expression of mitogen-activated protein kinase (MAPK) pathway proteins (p-JNK and p-Akt) and apoptosis proteins (Bax and Bcl-2) was detected using western blotting. RESULTS: SPRC reduced the levels of AST (p < 0.05) and ALT (p < 0.01) and decreased the release of the inflammatory cytokines. Mechanistically, SPRC increased H2S level (p < 0.05) and promoted cystathionine γ-lyase (CSE) expression (p < 0.05). SPRC inhibited the MAPK pathway activation and the apoptosis pathway. All the effects of SPRC were blocked by the CSE inhibitor PAG. CONCLUSIONS: SPRC prevents Con A-induced liver injury in mice by promoting CSE expression and producing endogenous H2S. The mechanisms include reducing the release of inflammatory cytokines, attenuating MAPK pathway activation, and alleviating apoptosis.


Asunto(s)
Enfermedad Hepática Crónica Inducida por Sustancias y Drogas , Sulfuro de Hidrógeno , Enfermedades Neurodegenerativas , Animales , Concanavalina A/toxicidad , Cisteína/farmacología , Citocinas , Sulfuro de Hidrógeno/metabolismo , Ratones
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