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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.
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Disprosio , Metales de Tierras Raras , Clima , Imanes , ChinaRESUMEN
In the double carbon background, riding the wind of new energy vehicles and the battery high nickelization, nickel resources rise along with the trend. In recent years, due to the influence of geopolitical conflicts and emergencies, as well as the speculation and control of international capital with its advantages and rules, the world may face price and security supply risks to a certain extent. Therefore, to obtain the most objective trade redistribution strategy, this paper first constructs the nickel material trade network, identifies the core trading countries and the main trade relations of nickel material trade, and finds that the flow of nickel material mainly occurred between a few countries. On this basis, a trade redistribution model is constructed based on the maximum entropy principle. Taking Indonesia, the largest exporter, and the largest trade relationship (Indonesia exports to China) as examples, the nickel material redistribution between countries when different supply risks occur are simulated. The results can provide an important reference for national resource recovery after the risk of the nickel trade.
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The input-output (IO) network is the quantitative description of an IO-based economy in which nodes represent industries and edges connecting nodes represent the economic connection between industries. Robustness refers to the ability of tolerating perturbations that might affect the system's functional body. There is both practical and theoretical significance to explore the robustness of the IO network for economic development. In this paper, we probe the robustness of the Chinese IO network based on the relative entropy of the probability distribution of network parameters (node degree, strongest path betweenness, downstream closeness and upstream closeness) under random node or edge failure and intentional node or edge attack. It is found that the Chinese IO network shows relatively weak robustness when it is under intentional attack, but relatively strong robustness when it is under random failure. Our experiment also verifies the applicability and effectiveness of the relative entropy model in measuring the robustness of the IO network.
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OBJECTIVE: We investigated the long-term visual outcomes and ocular complications of primary scleral-fixated posterior chamber intraocular lenses (SF-PC-IOLs) in patients with congenital lens subluxation. METHODS: We enrolled 53 patients (77 eyes) with congenital lens subluxation caused by ectopia lentis, Marfan syndrome, and Weill-Marchesani syndrome who underwent primary implantation of a SF-PC-IOL. All patients underwent a complete ophthalmic examination include visual acuity (VA), intraocular pressure (IOP), intraocular lenses (IOL) position, intraoperative complications and postoperative complications. Cox regression analysis and survival analysis were used to evaluate the risk factors for postoperative complications. RESULTS: Seventy seven eyes from 53 patients were included. Mean age at surgery was 23 ± 20 years (5 to 67 years), with a mean follow-up of 39 ± 27 months (12 to 130 months). The best-corrected VA improved from 0.84 ± 0.55 to 0.26 ± 0.43 logarithms of the minimum angle of resolution (p < 0.001). Best-corrected VA improved postoperatively in 73 eyes (94%). The main causes of reduced vision after surgery were retinal pathologies and amblyopia. Complications included transient intraocular haemorrhage (2 eyes, 2.6%), early vitreous incarceration (2 eyes, 2.6%), retinal detachment (6 eyes, 7.8%) and IOL dislocation (3 eyes, 3.9%). Cox regression showed that postoperative eye trauma was a risk factor for long-term postoperative complications. CONCLUSION: SF-PC-IOLs provide good visual outcomes in patients with congenital lens subluxation. The SF-PC-IOLs showed good stability, except in patients suffering from postsurgical eye trauma.
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Desplazamiento del Cristalino , Subluxación del Cristalino , Lentes Intraoculares , Desplazamiento del Cristalino/cirugía , Estudios de Seguimiento , Humanos , Implantación de Lentes Intraoculares , Subluxación del Cristalino/etiología , Subluxación del Cristalino/cirugía , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Esclerótica/cirugía , Técnicas de Sutura , Agudeza VisualRESUMEN
PURPOSE: To evaluate the visual outcomes and perioperative complications for cataract surgery in eyes with axial length (AL) >33.0 mm. DESIGN: Prospective clinical cohort study. METHODS: One hundred twenty-two eyes with moderate high myopia (26.0 mm ≤ AL < 28.0 mm, control group), and 118 eyes with extreme high myopia (AL > 33.0 mm, EHM group) were followed up after cataract surgery (1 week and 1 year post-op). Myopic maculopathy grading according to ATN system, best-corrected visual acuity (BCVA), and complications were compared. RESULTS: Postoperatively, BCVA in the EHM group improved significantly at both visits (both P < .001), despite being worse than that of the control group (both P < .05). The EHM group exhibited greater hyperopic refractive errors (P < .001), which were found to be associated with more severe T grade, longer AL, poorer second follow-up BCVA, and smaller anterior capsular opening (ACO) area. A higher incidence of retinal detachment and a more constricted ACO were observed in the EHM group (P = .030 and <.001, respectively), with the latter being significantly associated with longer AL and the absence of capsular tension ring (both P < .05). No difference in BCVA was found between the aphakic and pseudophakic eyes in the EHM group at both visits (both P > .05). CONCLUSION: Cataract surgery improves vision of eyes with AL >33 mm, yet the increased risk of perioperative complications requires attention. Leaving these eyes aphakic might be effective and safe in the long term.
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Longitud Axial del Ojo , Implantación de Lentes Intraoculares , Facoemulsificación , Complicaciones Posoperatorias , Agudeza Visual , Humanos , Agudeza Visual/fisiología , Estudios Prospectivos , Longitud Axial del Ojo/patología , Femenino , Masculino , Anciano , Persona de Mediana Edad , Resultado del Tratamiento , Seudofaquia/fisiopatología , Estudios de Seguimiento , Miopía Degenerativa/complicaciones , Miopía Degenerativa/fisiopatología , Complicaciones Intraoperatorias , Refracción Ocular/fisiologíaRESUMEN
The uneven spatial distribution of mineral resources necessitates the construction of mature global mineral governance system to ensure rational allocation of mineral resources. To this end, it is essential to analyze the structure of the global mineral governance system to provide a theoretical basis for the construction. The governance actor is the crucial element in driving the governance process, and country serves as the most central actor. Therefore, clarifying the roles and statuses of different countries in the governance system will be helpful to analyze the structure of the governance system. In the context of advancing globalization, a complex cooperative relationship has been presented between countries based on international organizations. Thus, we establish a national cooperation network based on the principle of the co-existence of countries in international organizations, to quantify these relationships between countries and identify the role and status of different countries, as well as the country communities in the cooperation network, by combining the characteristics of the countries in the network with the actual performance in the organizations. The research findings are as follow: (1) The UK, Germany, France, Sweden, and Canada play pivotal roles in promoting international cooperation as well as leading governance in the governance system. (2) Emerging economies are more actively engaged in these organizations and can promote international cooperation, but lack the capacity to assume leadership roles in governance. (3) The U.S. and China have a stronger ability to lead than to cooperate in the governance system. (4) Most African and South American countries, as well as some European nations, are marginalized in the governance system. (5) Countries with the same needs and similar economic and political conditions belong to the same community: The European countries and the U.S., consumer with a high level of economic and political development but low mineral resource endowment are in the first community. Canada, Australia, and certain African and South American countries, producers with high mineral resource endowments are in the second community. Most African and South American countries with lower levels of economic and political development are in the third group.
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Natural gas is regarded as the main transition energy under the carbon-neutral strategy and its main consumers are Organization for Economic Cooperation and Development countries, accounting for 44.5% of world consumption in 2021. In order to investigate the effects of technology, industry, and regions on natural gas consumption, 12 major Organization for Economic Cooperation and Development countries from three different country groups were selected in this paper to explore the consumption change. Firstly, the Logarithmetic Mean Divisia Index model is adopted to find out the driving factors. Then, the Tapio model is used to consider the decoupling state between natural gas consumption and economic growth. The results can be concluded as follows: (a) From 2000 to 2020, the technological progress effect has the biggest values of -148.86, followed by the industrial structure effect and the regional scale effect, with values of - 37.04 and 29.42, respectively. (b) From the perspective of industry view, these three effects have the largest impact on the secondary industry, followed by the tertiary industry and primary industry; (c) the regional scale effect has a positive effect on most countries, and the industrial structure effect and the regional scale effect have a negative effect on most countries; (d) the decoupling state vary differently in countries with different groups. Therefore, we concluded two policy recommendations for nature gas reduction: (a) Technological innovation is the most effective way for reducing natural gas consumption; (b) Industrial structure optimization can help save natural gas consumption.
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Device passivation through ultraclean hexagonal BN encapsulation has proven to be one of the most effective ways of constructing high-quality devices with atomically thin semiconductors that preserve the ultraclean interface quality and intrinsic charge transport behavior. However, it remains challenging to integrate lithography-compatible contact electrodes with flexible distributions and patterns. Here, we report the feasibility of a straightforward integration of lithography-defined contacts into BN-encapsulated two-dimensional field-effect transistors (2D FETs), giving rise to overall device quality comparable to the state-of-the-art results from the painstaking pure dry transfer processing. The electronic characterization of FETs consisting of WSe2 and MoS2 channels reveals an extremely low scanning hysteresis of â¼2 mV on average, a low density of interfacial charged impurities of â¼1011 cm-2, and generally high charge mobilities over 1000 cm2 V-1 s-1 at low temperatures. The overall high device qualities verify the viability of directly integrating lithography-defined contacts into BN-encapsulated devices to exploit their intrinsic charge transport properties for advanced electronics.
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In recent years, increasing attention has been given to the potential supply risks of critical battery materials, such as cobalt, for electric mobility transitions. While battery technology and recycling advancement are two widely acknowledged strategies for addressing such supply risks, the extent to which they will relieve global and regional cobalt demand-supply imbalance remains poorly understood. Here, we address this gap by simulating historical (1998-2019) and future (2020-2050) global cobalt cycles covering both traditional and emerging end uses with regional resolution (China, the U.S., Japan, the EU, and the rest of the world). We show that cobalt-free batteries and recycling progress can indeed significantly alleviate long-term cobalt supply risks. However, the cobalt supply shortage appears inevitable in the short- to medium-term (during 2028-2033), even under the most technologically optimistic scenario. Our results reveal varying cobalt supply security levels by region and indicate the urgency of boosting primary cobalt supply to ensure global e-mobility ambitions.
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Cobalto , Litio , Suministros de Energía Eléctrica , Reciclaje , TecnologíaRESUMEN
To improve the efficiency of polysaccharide extraction, vacuum technology was used to breakdown the cell wall to extract polysaccharides from Lentinus edodes stipe, and the optimal parameters were optimized by response surface methodology. Then the antioxidant activities in vitro of the polysaccharides were evaluated. Results showed that the optimal conditions for polysaccharide extraction were temperature of 62 °C, vacuum of 0.08 MPa, stirring speed of 1200 r/min, time of 25 min and material/liquid ratio of 1:26 (g/mL). Under these conditions, the yield of polysaccharide was 4.28%. The decolorization rate and deproteinization rate of polysaccharides treated by kaolin and hydrogen peroxide were higher than that of activated carbon. However, there was no significant influence on the polysaccharide retention rate, that was about 80%. Results also indicated that polysaccharide treated with activated carbon could obtain higher antioxidant activity.
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A 54-year-old woman presented with recurrent redness and blurred vision of the left eye with elevated intraocular pressure (IOP) for one year. She was treated as "iridocyclitis" and ``Posner-Schlossman syndrome'' at the local hospitals. However, the patient developed intermittent ocular inflammation and hyphema. Patient had a cataract surgery and intraocular lens (IOL) implantation in the left eye one year before at the local hospital. A diagnostic procedure was performed and the possible pathogenesis was discussed.
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Marine polysaccharides are attracting increasing attention in medical and pharmaceutical development because of their important biological properties. The seaweed polysaccharides have now become a rich resource of potential antiviral drugs due to their antiviral activities against various viruses. The structural diversity and complexity of marine polysaccharides and their derivatives contribute to their antiviral activities in different phases of many different viral infection processes. This review mainly introduces the different types of seaweed polysaccharides and their derivatives with potent antiviral activities. Moreover, the antiviral mechanisms and medical applications of certain marine polysaccharides from seaweeds are also demonstrated.
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Antivirales/química , Antivirales/farmacología , Polisacáridos/química , Polisacáridos/farmacología , Algas Marinas/química , Virus/efectos de los fármacosRESUMEN
AIMS: To evaluate the efficacy of lens removal plus intraocular lens (IOL) implantation for spherophakia with secondary glaucoma. METHODS: A series of 19 patients (n=24 eyes) were split into two groups according to the degree of zonular abnormality as follows: group 1 (within the range of one quadrant, n=7 eyes) and group 2 (beyond the range of one quadrant, n=17 eyes). The patients in group 1 underwent phacoemulsification+capsular tension ring (CTR)+IOL, whereas patients in group 2 underwent pars plana lensectomy with scleral-fixated posterior chamber (PC) IOL implantation. The best corrected visual acuity (BCVA) (logMAR unit) and intraocular pressure (IOP) were documented at presentation and at 1â day, 7â days, 3â months, 1â year and 3â years postoperatively. RESULTS: The IOP in both groups significantly decreased after surgery (group 1:28.84±5.36â mmâ Hg at presentation, 15.86±0.79â mmâ Hg at the 3-year visit, t=6.34, p=0.000; group 2:26.18±12.16â mmâ Hg at presentation, 14.54±3.40â mmâ Hg at the 3-year visit, t=3.80, p=0.01). The BCVA increased from 0.79±0.36 at baseline to 0.44±0.38 at the 3-year follow-up but did not reach a significantly different level in group 1 (t=1.72, p=0.11), whereas the BCVA significantly increased from 1.15±0.75 at baseline to 0.43±0.38 at the 3-year visit in group 2 (t=3.45, p=0.02). CONCLUSIONS: Both phacoemulsification+CTR+IOL and lensectomy with scleral-fixated PC IOL implantation are effective in lowering the IOP and enhancing the visual acuity in patients with spherophakia and secondary glaucoma.