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1.
Cells Tissues Organs ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38824915

RESUMO

Background Acupuncture has been used for pain management for thousands of years. However, it is largely unclear whether this therapeutic approach can effectively reduce heart failure-associated symptoms, including dyspnea. Summary The hypothesis posited in this study was that acupuncture does indeed aid in management of such symptoms and was motivated by the following statistics that establish a requisite need for efficient management of dyspnea to improve patient outcomes with heart failure: In 2020, an estimated 6.2 million adults in the USA had a heart failure diagnosis; in 2018, 379,800 death certificates reported heart failure; and the national cost of heart failure in 2012 was approximately $30.7 billion. The methodology employed to conduct this study involved review of trial data extracted from review of papers pertaining to acupuncture, symptoms of heart failure and dyspnea, from academic and clinical data repositories subject to various inclusion and exclusion criteria. Of the initial set of 293 studies identified, the resulting inclusion set comprised 30 studies. The analysis conducted revealed that the highest frequency of combined acupuncture points prescribed for the foregoing search criteria were as follow: BL13, BL23, LU9, LU5, Dingchuan, LI4, PC6 and HT7. A meta-analysis of combined pooled p-values for the studies revealed that acupuncture does aid in the management of symptoms of dyspnea and heart failure, subject to various limitations including but not limited to heterogeneity inherent between the studies in the inclusion set that was analyzed. Such limitations underscore the need to restrict generalizations from the conclusions of this study. Key messages The impact and novelty of this research study is its attempt to target the apparent paucity of literature that focuses on the management of dyspnea specifically in the context of heart failure with acupuncture, and to bridge the gap of the application of acupuncture research on dyspnea to the cardiovascular context of heart failure. Further statistical analysis and a pilot study are warranted to consolidate or nullify the results of the research undertaken under this review study.

2.
Fundam Res ; 4(2): 379-393, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38933507

RESUMO

The Belt and Road Initiative (BRI) is a central policy within China's regional development and foreign trade strategy. Traditional trade has typically depended on economic valuation of resources, while the embedded environmental value is rarely considered. This situation exists in most BRI trade evaluations. To address BRI environmental sustainability issues, we consider the role of pivotal Chinese provinces and their key trade partners (ASEAN countries) as an illustration for the environmental value of resource exchanges. Emergy accounting is used as the valuation tool for a sample period of seventeen years. Key results include: (1) Emergy valuations show sustainability of sample provinces decreased over time; (2) ASEAN countries such as Indonesia, Malaysia, Singapore, Thailand, and Vietnam play significant resource roles for provincial economic systems; (3) Diverse trends in trade between pivotal provinces and ASEAN countries resulted in an unbalanced trade structure from trade. Policy implications are proposed to promote a more globally sustainable and fair trade using BRI as an established trade policy.

3.
Fundam Res ; 4(1): 167-177, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38933841

RESUMO

Lithium-ion battery (LIB) is the key technology for climate change mitigation. The sustainability of LIB supply chain has caused widespread concern since the material utilization efficiency of LIB supply chain has not been well investigated. This study aims to fill this research gap by conducting a dynamic material flow analysis of lithium in China from 2015 to 2021. Results indicate that within the temporal boundary, lithium flow and in-use stock grew significantly in China due to the rapid development of the EV market, with lithium flow in domestic production of basic chemicals increasing by 614% to 100 kt, end-use consumption increasing by 160% to 35 kt, and in-use stock increasing by 62% to 195 kt. China has been a net importer of lithium, of which cumulative imports and exports were 343 kt and 169 kt, respectively. In addition, 103 kt of lithium was converted to inventories or was lost during the processing from 2015 to 2021. By optimizing inventory and processing, developing substitutes for lithium for non-battery applications, and improving lithium recycling, China's net import dependency of lithium could be reduced from 27%-86% to 0%-16%. Our study demonstrates that it is urgent to improve material utilization efficiency so that the lithium resource supply can be secured.

4.
Opt Express ; 32(11): 18800-18811, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859029

RESUMO

In sixth generation (6G) communications, terahertz (THz) communication is one of the most important technologies in the future due to its ultra-bandwidth, where hybrid beamforming has been widely used to solve the severe transmission attenuation in the THz band. However, the use of frequency-flat phase shifters in hybrid beamforming leads to the beam split effect. To solve the beam split influence, we propose a novel optical true time delay compensation network (OTTDCN)-based phase precoding structure with low power consumption. In the proposed scheme, the OTTDCN pre-generates multiple beam compensation modes to achieve phase compensation for different frequencies. As a result, the compensated beams can be reoriented toward the target direction at different frequencies. Moreover, a low-complexity beam compensation mode-based hybrid precoding algorithm is proposed, where the selection of the optimal beam compensation modes used for all radio-frequency (RF) chains with finite beam compensation modes is considered. The results show that the OTTDCN-based phase precoding scheme can effectively alleviate the beam split effect with low power consumption and achieve near-optimal performance.

5.
Opt Lett ; 49(5): 1129-1132, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38426955

RESUMO

Auxiliary laser heating has become a widely adopted method for Kerr soliton frequency comb generation in optical microcavities, thanks to its reliable and easy-to-achieve merits for solving the thermal instability during the formation of dissipative Kerr solitons. Here, we conduct optimization of auxiliary laser heating by leveraging the distinct loss and absorption characteristics of different longitudinal and polarization cavity modes. We show that even if the auxiliary and pump lasers enter orthogonal polarization modes, their mutual photothermal balance can be efficient enough to maintain a cavity thermal equilibrium as the pump laser enters the red-detuning soliton regime, and by choosing the most suitable resonance for the auxiliary and pump lasers, the auxiliary laser power can be reduced to 20% of the pump laser and still be capable of warranting soliton generation. Moreover, we demonstrate soliton comb generation using integrated laser modules with a few milliwatt on-chip pump and auxiliary powers, showcasing the potential for further chip integration of the auxiliary laser heating method.

6.
Nat Commun ; 15(1): 1404, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360960

RESUMO

Multiple emulsions are usually stabilized by amphiphilic molecules that combine the chemical characteristics of the different phases in contact. When one phase is a liquid crystal (LC), the choice of stabilizer also determines its configuration, but conventional wisdom assumes that the orientational order of the LC has no impact on the stabilizer. Here we show that, for the case of amphiphilic polymer stabilizers, this impact can be considerable. The mode of interaction between stabilizer and LC changes if the latter is heated close to its isotropic state, initiating a feedback loop that reverberates on the LC in form of a complete structural rearrangement. We utilize this phenomenon to dynamically tune the configuration of cholesteric LC shells from one with radial helix and spherically symmetric Bragg diffraction to a focal conic domain configuration with highly complex optics. Moreover, we template photonic microparticles from the LC shells by photopolymerizing them into solids, retaining any selected LC-derived structure. Our study places LC emulsions in a new light, calling for a reevaluation of the behavior of stabilizer molecules in contact with long-range ordered phases, while also enabling highly interesting photonic elements with application opportunities across vast fields.

7.
Sci Adv ; 10(3): eadf8666, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38241376

RESUMO

Fiber-optic distributed acoustic sensing (DAS) has proven to be a revolutionary technology for the detection of seismic and acoustic waves with ultralarge scale and ultrahigh sensitivity, and is widely used in oil/gas industry and intrusion monitoring. Nowadays, the single-frequency laser source in DAS becomes one of the bottlenecks limiting its advance. Here, we report a dual-comb-based coherently parallel DAS concept, enabling linear superposition of sensing signals scaling with the comb-line number to result in unprecedented sensitivity enhancement, straightforward fading suppression, and high-power Brillouin-free transmission that can extend the detection distance considerably. Leveraging 10-line comb pairs, a world-class detection limit of 560 fε/√Hz@1 kHz with 5 m spatial resolution is achieved. Such a combination of dual-comb metrology and DAS technology may open an era of extremely sensitive DAS at the fε/√Hz level, leading to the creation of next-generation distributed geophones and sonars.

8.
Adv Mater ; 36(8): e2305251, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37797655

RESUMO

The wavelength- and polarization-selective Bragg reflection of visible light exhibited by films produced by drying cholesteric liquid crystal (CLC) suspensions of cellulose nanocrystals (CNCs) render these biosourced nanoparticles highly potent for many optical applications. While the conventionally produced films are flat, the CLC-derived helical CNC arrangement would acquire new powerful features if given spherical curvature. Drying CNC suspension droplets does not work, because the onset of kinetic arrest in droplets of anisotropic colloids leads to severe buckling and loss of spherical shape. Here, these problems are avoided by confining the CNC suspension in a spherical microshell surrounding an incompressible oil droplet. This prevents buckling, ensures strong helix pitch compression, and produces single-domain cholesteric spherical reflector particles with distinct visible color. Interestingly, the constrained shrinkage leads to spontaneous puncturing, leaving every particle with a single hole through which the inner oil phase can be extracted for recycling. By mixing two different CNC types at varying fractions, the retroreflection color is tuned throughout the visible spectrum. The new approach adds a versatile tool in the quest to utilize bioderived CLCs, enabling spherically curved particles with the same excellent optical quality and smooth surface as previously obtained only in flat films.

9.
Biochem Biophys Res Commun ; 695: 149401, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38154264

RESUMO

Human calcium sensing receptor (CaSR) senses calcium ion concentrations in vivo and is an important class of drug targets. Mutations in the receptor can lead to disorders of calcium homeostasis, including hypercalcemia and hypocalcemia. Here, 127 CaSR-targeted nanobodies were generated from camels, and four nanobodies with inhibitory function were further identified. Among these nanobodies, NB32 can effectively inhibit the mobilization of intracellular calcium ions (Ca2+i) and suppress the G12/13 and ERK1/2 signaling pathways downstream of CaSR. Moreover, it enhanced the inhibitory effect of the calcilytics as a negative allosteric modulator (NAM). We determined the structure of complex and found NB32 bound to LB2 (Ligand-binding 2) domain of CaSR to prevent the interaction of LB2 domains of two protomers to stabilize the inactive state of CaSR.


Assuntos
Hipercalcemia , Hipocalcemia , Anticorpos de Domínio Único , Humanos , Receptores de Detecção de Cálcio/metabolismo , Cálcio/metabolismo , Hipocalcemia/genética , Hipercalcemia/genética
10.
Heliyon ; 9(11): e21250, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38027842

RESUMO

Clean energy can lead to significant health benefits. Making it accessible throughout the world can address many ills. We delve deeply into one example-the transition toward clean residential heating and its relationship to health benefits-in China. We find that the health benefits can outweigh costs from energy expenses in northern provinces. Low-income households enjoy larger health benefits but also experience a higher expense increase, suggesting that extra subsidies or stimuli are needed to help them benefit from clean energy. Our findings suggest that clean energy transitions should be promoted in developing economies due to improved social health, lessened medical costs, and significant environmental improvements.

11.
Opt Express ; 31(22): 37154-37161, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-38017850

RESUMO

Microresonator soliton frequency combs offer unique flexibility in synthesizing microwaves over a wide range of frequencies. Therefore, it is very important to study the time jitter of soliton microcombs. Here, we fabricate optical microresonators with perfect transmission spectrum that characterizes highly uniform extinction ratio and absence of mode interactions by laser machining high-purity silica fiber preforms. Based on such perfect whispering-gallery-mode cavity, We demonstrate that K-band microwave with ultra-low phase noise (-83 dBc/Hz@100 Hz; -112 dBc/Hz@1kHz; -133 dBc/Hz@10kHz) can be generated by photo-detecting the repetition rate of a soliton microcomb. Also, with the Raman scattering and dispersive wave emission largely restricted, we show that ultra-low time jitter soliton has a wide existence range. Our work illuminates a pathway toward low-noise photonic microwave generation as well as the quantum regime of soliton microcombs.

12.
Sci Total Environ ; 904: 167248, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37739081

RESUMO

Palladium (Pd) is a strategic metal and can help reduce environmental pollution, especially from vehicle exhausts. China is the world's largest Pd consumer, but with very limited reserves. However, Pd anthropogenic cycles remain unclear in China. This study aims to uncover the dynamic Pd flows and stocks in China for the period of 2001-2020 by conducting dynamic material flow analysis. The results show that the demand for Pd had increased by 10 folds during the study period due to stricter vehicle emissions policies. Also, China mainly imported such resource from the United States, Western Europe, and East Asia, with a share of 88.8 %. However, due to insufficient end-of-life vehicle (ELV) recycling system, the total recycled Pd was only 12.3 tons although the end-of-life Pd flow increased from 3.7 tons in 2001 to 30.8 tons in 2020. This implies a great Pd recycling potential. Therefore, it is urgent to promote Pd recycling by establishing an effective Pd recycling system. In addition, other policy recommendations, such as diversifying Pd import partners, increasing Pd emergency reserves, and economic instruments, are raised by considering the Chinese realities so that the overall Pd resource efficiency can be improved.

13.
iScience ; 26(9): 107701, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37694146

RESUMO

Characterizing material flows and environmental impacts of plastic value chain is crucial for sustainable plastic management. Here, we combine material flow analysis and life cycle assessment methods to map the flows of eight major plastics and investigate the multiple environmental impacts of China's plastic value chain. We find that packaging and textile sectors dominate plastic consumption and are responsible for the value chain environmental burdens, but with low recycling rates. Major environmental impacts are generated in plastic production and product manufacturing stages because of the consumption of coal-based feedstocks and electricity. We therefore set up six scenarios by considering carbon neutrality energy pathway, plastic recycling improvement, and technology updating, finding that the value chain environmental impact can be reduced by 14%-57% in 2060 under combined scenario. Particularly, carbon neutrality renewable energy pathway plays an important role. These findings provide valuable insights to identify key mitigation pathways for plastic value chain.

14.
Opt Lett ; 48(15): 3965-3968, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37527094

RESUMO

All-optical phase regeneration aims at restoring the phase information of coherently encoded data signals directly in the optical domain so as to compensate for phase distortions caused by transceiver imperfections and nonlinear impairments along the transmission link. Although it was proposed two decades ago, all-optical phase regeneration has not been seen in realistic networks to date, mainly because this technique entails complex bulk modules and relies on high-precision phase sensitive nonlinear dynamics, both of which are adverse to field deployment. Here, we demonstrate a new, to the best of our knowledge, architecture to implement all-optical phase regeneration using integrated photonic devices. In particular, we realize quadrature phase quantization by exploring the phase-sensitive parametric wave mixing within on-chip silicon waveguides, while multiple coherent pump laser tones are provided by a chip-scale micro-cavity Kerr frequency comb. Multi-channel all-optical phase regeneration is experimentally demonstrated for 40 Gbps QPSK data, achieving the best SNR improvement of more than 6 dB. Our study showcases a promising avenue to enable the practical implementation of all-optical phase regeneration in realistic long-distance fiber transmission networks.

15.
Environ Sci Pollut Res Int ; 30(39): 90814-90829, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37462871

RESUMO

Large-scaled interregional trade is based upon massive exchanges of natural resources, leading to more environmental emissions and economic imbalance. China is the largest trade country in the world and has to face such challenges since different Chinese provinces are in different development stages with different resource endowments. By using the latest multi-regional input-output (MRIO) tables and exergy accounting, this study aims to investigate natural resources and added values embodied in interregional trade in China for years of 2012, 2015, and 2017. Regional environmental inequality (REI) index and logarithmic mean Divisia index (LMDI) were applied to measure the imbalance states and uncover corresponding driving factors. Results show that the total trade volumes in the middle Yellow River and eastern coastal regions were generally higher than those in other regions, together accounting for 41.50 ~ 41.78% of the total trade volume during the study period. The major flows of embodied natural resources shifted from the middle Yellow River region to western coastal, eastern coastal, and southern coastal regions. The northern coastal and eastern coastal regions were the major exporters of embodied added value. Less developed regions had higher REI values, indicating more environmental and economic losses than developed regions. Natural resources intensity was the major impact factor on the trade imbalances in most provinces. This study provides valuable insights for alleviating trade imbalance and promoting sustainable natural resources management based on cross-regional collaboration.


Assuntos
Dióxido de Carbono , Recursos Naturais , China , Dióxido de Carbono/análise
16.
Nature ; 619(7969): 248-251, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37430110
17.
J Struct Biol ; 215(3): 107996, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37419228

RESUMO

The evolving SARS-CoV-2 Omicron strain has repeatedly caused widespread disease epidemics, and effective antibody drugs continue to be in short supply. Here, we identified a batch of nanobodies with high affinity for receptor binding domain (RBD) of SARS-CoV-2 spike protein, separated them into three classes using high performance liquid chromatography (HPLC), and then resolved the crystal structure of the ternary complexes of two non-competing nanobodies (NB1C6 and NB1B5) with RBD using X-ray crystallography. The structures showed that NB1B5 and NB1C6 bind to the left and right flank of the RBD, respectively, and that the binding epitopes are highly conserved cryptic sites in all SARS-CoV-2 mutant strains, as well as that NB1B5 can effectively block the ACE2. These two nanobodies were covalently linked into multivalent and bi-paratopic formats, and have a high affinity and neutralization potency for omicron, potentially inhibiting viral escape. The binding sites of these two nanobodies are relatively conserved, which help guide the structural design of antibodies targeting future variants of SARS-CoV-2 to combat COVID-19 epidemics and pandemics.


Assuntos
COVID-19 , Anticorpos de Domínio Único , Humanos , SARS-CoV-2/genética , Anticorpos , Epitopos/genética , Anticorpos Neutralizantes
18.
Ecotoxicol Environ Saf ; 259: 115007, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37209571

RESUMO

Wastewater treatment plants (WWTPs) are significant contributors to energy consumption and anthropogenic greenhouse gas (GHG) emissions. For achieving carbon reduction in the wastewater treatment industry, the direct and indirect GHG emissions generated by WWTPs need to be understood from a holistic perspective. This study estimated GHG emissions from WWTPs at the country scale by integrating process-based life cycle assessment and statistical data. On-site data were collected from 17 WWTPs of various regions in China. Uncertainty analysis based on Monte Carlo was also performed, so as to provide more reliable results. The results show that life cycle GHG emissions generated from the wastewater treatment process vary from 0.29 kg CO2 eq/m3 to 1.18 kg CO2 eq/m3 based on 17 sample WWTPs. The key factors contributing to overall GHG emissions are also identified as carbon dioxide (fossil) and methane (fossil) to air mainly generated from electricity generation, and methane (biogenic) and nitrous oxide (biogenic) to air mainly generated from wastewater treatment. National average GHG emissions was evaluated with the value of 0.88 kg CO2 eq/m3, with on-site GHG emissions and off-site electricity-based GHG emissions accounting for 32% and 34%, respectively. The total GHG emissions generated from wastewater treatment are 56.46 billion kg CO2 eq in 2020, with Guangdong province having the dominant contribution. Policy suggestions (e.g., further adjusting the electricity grid toward a low carbon structure, improving technology to promote treatment efficiency and energy recovery) were highly recommended so that national GHG emissions of WWTPs can be reduced. In order to achieve the synergy of pollutant removal and GHG emission reduction, policy-making on wastewater treatment should be tailored to specific local conditions.


Assuntos
Gases de Efeito Estufa , Purificação da Água , Animais , Gases de Efeito Estufa/análise , Eliminação de Resíduos Líquidos/métodos , Dióxido de Carbono/análise , Efeito Estufa , Metano/análise , China , Estágios do Ciclo de Vida
19.
Adv Sci (Weinh) ; 10(19): e2301414, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37186075

RESUMO

Cylindrically symmetric cholesteric liquid crystal elastomer (CLCE) fibers templated by tubular confinement are reported, displaying mechanochromic, thermochromic, and thermomechanical responses. The synthesis inside a sacrificial tube secures radial orientation of the cholesteric helix, and the ground state retroreflection wavelength is easily tuned throughout the visible spectrum or into the near-infrared by varying the concentration of a chiral dopant. The fibers display continuous, repeatable, and quantitatively predictable mechanochromic response, reaching a blue shift of more than -220 nm for 180% elongation. The cylindrical symmetry renders the response identical in all directions perpendicular to the fiber axis, making them exceptionally useful for monitoring complex strains, as demonstrated in revealing local strain during tying of different knots. The CLCE reflection color can be revealed with high contrast against any background by taking advantage of the circularly polarized reflection. Upon heating, the fibers respond-fully reversibly-with red shift and radial expansion/axial contraction. However, there is no transition to an isotropic state, confirming a largely forgotten theoretical prediction by de Gennes. These fibers and the easy way of making them may open new windows for large-scale application in advanced wearable technology and beyond.

20.
Protein Expr Purif ; 207: 106267, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37030644

RESUMO

Coronavirus Papain-like protease (PLpro) mediates the cleavage of viral polyproteins and assists the virus escaping from innate immune response. Thus, PLpro is an attractive target for the development of broad-spectrum drugs as it has a conserved structure across different coronaviruses. In this study, we purified SARS-CoV-2 PLpro as an immune antigen, constructed a nanobody phage display library, and identified a set of nanobodies with high affinity for SARS-CoV-2. In addition, enzyme activity experiments demonstrated that two nanobodies had a significant inhibitory effect on the PLpro. These nanobodies should therefore be investigated as candidates for the treatment of coronaviruses.


Assuntos
COVID-19 , Anticorpos de Domínio Único , Humanos , Proteases Semelhantes à Papaína de Coronavírus , SARS-CoV-2 , Peptídeo Hidrolases , Papaína/química
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