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1.
Sci Rep ; 14(1): 7640, 2024 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561402

RESUMO

The purpose of this study is to deeply understand the psychological state of boxers before the competition, and explore an efficient boxing action classification and recognition model supported by artificial intelligence (AI) technology through these psychological characteristics. Firstly, this study systematically measures the key psychological dimensions of boxers, such as anxiety level, self-confidence, team identity, and opponent attitude, through psychological scale survey to obtain detailed psychological data. Then, based on these data, this study innovatively constructs a boxing action classification and recognition model based on BERT fusion 3D-ResNet, which not only comprehensively considers psychological information, but also carefully considers action characteristics to improve the classification accuracy of boxing actions. The performance evaluation shows that the model proposed in this study is significantly superior to the traditional model in terms of loss value, accuracy and F1 value, and the accuracy reaches 96.86%. Therefore, through the comprehensive application of psychology and deep learning, this study successfully constructs a boxing action classification and recognition model that can fully understand the psychological state of boxers, which provides strong support for the psychological training and action classification of boxers.


Assuntos
Boxe , Inteligência Artificial , Psicologia do Esporte , Redes Neurais de Computação
2.
Adv Mater ; 36(14): e2310379, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38183310

RESUMO

Antiferromagnets constitute promising contender materials for next-generation spintronic devices with superior stability, scalability, and dynamics. Nevertheless, the perception of well-established ferromagnetic spintronics underpinned by spontaneous magnetization seemed to indicate the inadequacy of antiferromagnets for spintronics-their compensated magnetization has been perceived to result in uncontrollable antiferromagnetic order and subtle magnetoelectronic responses. However, remarkable advancements have been achieved in antiferromagnetic spintronics in recent years, with consecutive unanticipated discoveries substantiating the feasibility of antiferromagnet-centered spintronic devices. It is emphasized that, distinct from ferromagnets, the richness in complex antiferromagnetic crystal structures is the unique and essential virtue of antiferromagnets that can open up their endless possibilities of novel phenomena and functionality for spintronics. In this Perspective, the recent progress in antiferromagnetic spintronics is reviewed, with a particular focus on that based on several kinds of antiferromagnets with special antiferromagnetic crystal structures. The latest developments in efficiently manipulating antiferromagnetic order, exploring novel antiferromagnetic physical responses, and demonstrating prototype antiferromagnetic spintronic devices are discussed. An outlook on future research directions is also provided. It is hoped that this Perspective can serve as guidance for readers who are interested in this field and encourage unprecedented studies on antiferromagnetic spintronic materials, phenomena, and devices.

3.
Nano Lett ; 24(2): 584-591, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38165127

RESUMO

Cu2S likely plays an important role in the sharp resistivity transition of LK-99. Nevertheless, this immediately arouses an intriguing question of whether the extraordinary room-temperature colossal magnetoresistance in the initial reports, which has been less focused, originates from Cu2S as well. To resolve this issue, we have systematically investigated the electrical transport and magnetotransport properties of near-stoichiometric Cu2S pellets and thin films. Neither Cu2S nor LK-99 containing Cu2S in this study was found to exhibit the remarkable magnetoresistance effect implied by Lee et al. This implies that Cu2S could not account for all of the intriguing transport properties of the initially reported LK-99, and the initially reported LK-99 samples might contain magnetic impurities. Moreover, based on the crystal-structure-sensitive electrical properties of Cu2S, we have constructed a piezoelectric-strain-controlled device and obtained a giant and reversible resistance modulation of 2 orders of magnitude at room temperature, yielding a huge gauge factor of 160,000.

4.
Artigo em Inglês | MEDLINE | ID: mdl-35409653

RESUMO

How will the dual structural effects, represented by industrial structure and energy structure, affect the future correlation between economic growth and CO2 emissions? Taking Jilin Province as an example, this study explores the dynamic driving mechanism of dual structural effects on the correlation between economic growth and CO2 emissions by innovatively building an integrated simulation model from 1995 to 2015 and setting different scenarios from 2016 to 2050. Correspondingly, the concept of marginal utility and the method of variance decomposition analysis are introduced to reveal the mechanism. The results show that the energy structure is different while the industrial structure tends to be similar when CO2 emissions reach the peak under different scenarios. The slower the dual structure adjustment, the more significant the upward trend appears before the peak. The contribution of the dual structural effects to CO2 emissions caused by unit GDP growth is basically the same in peak year. With the transformation of socio-economy, the positive driving effect of the industrial structure will gradually weaken, while the negative driving effect of the energy structure will gradually increase. The methods and results presented can provide insights into sensible trade-offs of CO2 emissions and economic growth in different countries/regions during structural transitions.


Assuntos
Condução de Veículo , Desenvolvimento Econômico , Dióxido de Carbono/análise , China , Indústrias
5.
Artigo em Inglês | MEDLINE | ID: mdl-35206308

RESUMO

The CO2 emission-mitigation policies adopted in different Chinese cities are important for achieving national emission-mitigation targets. China faces enormous inequalities in terms of regional economic development and urbanization, with some cities growing rapidly, while others are shrinking. This study selects 280 cities in China and divides them into two groups of growing cities and two groups of shrinking cities. This is achieved using an index called "urban development degree," which is calculated based on economic, demographic, social, and land-use indicators. Then, the 280 cities' CO2 emission characteristics are examined, and extended STIRPAT (stochastic impacts by regression on population, affluence, and technology) is used to verify the influencing factors. We find that rapidly growing cities (RGCs) present a trend of fluctuating growth in CO2 emissions, rapidly shrinking cities (RSCs) show an inverted U-shaped trend, and slightly growing (SGCs) and slightly shrinking cities (SSCs) show a trend of rising first, followed by steady development. Moreover, for growing cities, the population, economy, and proportion of tertiary industry have positive effects on carbon emissions, while technology has negative effects. For shrinking cities, the population and economy have significant positive effects on carbon emissions, while technology and the proportion of tertiary industry have negative effects.


Assuntos
Dióxido de Carbono , Carbono , Dióxido de Carbono/análise , China , Cidades , Desenvolvimento Econômico , Urbanização
6.
J Tradit Chin Med ; 41(4): 617-623, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34392655

RESUMO

OBJECTIVE: To investigate the efficacy of Sijunzi decoction () on limb weakness in a rat model of spleen Qi deficiency (SQD), and to study its effect on mitophagy in skeletal muscle through adenosine monophosphate-activated protein kinase (AMPK) / unc-51 like autophagy activating kinase 1 (ULK1) signaling. METHODS: SQD model rats were produced by fasting combined with forced swimming method for 15 d. After model assessment, rats were randomly divided into four groups of 10 [low/middle/high (L/M/H) Sijunzi decoction dose groups and a normal saline (S) group]. Limb holding power (HP) and body mass (BM) were measured after 2 weeks of treatment. Following euthanasia, quadriceps femoris were dissected and myofiber and mitochondrial morphology were observed by transmission electron microscopy (TEM). Mitochondrial membrane potential (MMP), adenosine triphosphatase (ATP) and reactive oxygen species (ROS) levels were determined using colorimetric methods, and immunoblot analysis of Microtubule-associated protein light chain 3 (LC3) and Sequestosome 1 (p62) was performed to monitor mitophagy and AMPK/ULK1 signaling. RESULTS: Compared with control (C) group rats, in the S group, HP was reduced, the myofiber Z line was disordered, mitochondria were scattered, and numerous vacuoles and mitophagy were observed. MMP and ATP levels were reduced, ROS levels were elevated, and LC3B expression, and p-AMPKα (Thr172)/AMPKα, p-ULK1 (Ser555)/ULK1, and p-Raptor (Ser792)/Raptor ratios were increased, while p62 expression and p-mTOR (Ser2448)/mTOR and p-ULK1 (Ser757)/ULK1 ratios were decreased. After treatment, compared with the S group, HP was improved in M and H groups but not in the L group. Mitophagy was reduced in M, H and L groups but the Z line was disordered and vacuolization remained in the L group. ATP levels were elevated in M, H and L groups, and MMPs were elevat-ed in M and H groups but not in the L group. ROS levels were decreased in M, H and L groups, as were LC3B expression and p-Raptor (Ser792)/Raptor ratios, while p62 expression and p-mTOR (Ser2448)/mTOR and p-ULK1 (Ser757)/ULK1 ratios were increased in M and H groups but not in the L group. p-AMPKα (Thr172)/AMPKα and p-ULK1 (Ser555)/ULK1 ratios were decreased in M, H and L groups. CONCLUSIONS: Sijunzi decoction improved HP, possibly by inhibiting mitophagy via suppression of AMPK/ULK1 signaling. This restored mitochondrial morphology and improved oxidative phosphorylation, which contributed to recovery of limb weakness in SQD model rats.


Assuntos
Qi , Baço , Monofosfato de Adenosina , Animais , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/genética , Medicamentos de Ervas Chinesas , Proteínas Quinases , Ratos
7.
Front Oncol ; 11: 794735, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35127502

RESUMO

Glutamine, like glucose, is a major nutrient consumed by cancer cells, yet these cells undergo glutamine starvation in the cores of tumors, forcing them to evolve adaptive metabolic responses. Pharmacologically targeting glutamine metabolism or withdrawal has been exploited for therapeutic purposes, but does not always induce cancer cell death. The mechanism by which cancer cells adapt to resist glutamine starvation in cisplatin-resistant non-small-cell lung cancer (NSCLC) also remains uncertain. Here, we report the potential metabolic vulnerabilities of A549/DDP (drug-resistant human lung adenocarcinoma cell lines) cells, which were more easily killed by the iron chelator deferoxamine (DFO) during glutamine deprivation than their parental cisplatin-sensitive A549 cells. We demonstrate that phenotype resistance to cisplatin is accompanied by adaptive responses during glutamine deprivation partly via higher levels of autophagic activity and apoptosis resistance characteristics. Moreover, this adaptation could be explained by sustained glucose instead of glutamine-dominant complex II-dependent oxidative phosphorylation (OXPHOS). Further investigation revealed that cisplatin-resistant cells sustain OXPHOS partly via iron metabolism reprogramming during glutamine deprivation. This reprogramming might be responsible for mitochondrial iron-sulfur [Fe-S] cluster biogenesis, which has become an "Achilles' heel," rendering cancer cells vulnerable to DFO-induced autophagic cell death and apoptosis through c-Jun N-terminal kinase (JNK) signaling. Finally, in vivo studies using xenograft mouse models also confirmed the growth-slowing effect of DFO. In summary, we have elucidated the adaptive responses of cisplatin-resistant NSCLC cells, which balanced stability and plasticity to overcome metabolic reprogramming and permitted them to survive under stress induced by chemotherapy or glutamine starvation. In addition, for the first time, we show that suppressing the growth of cisplatin-resistant NSCLC cells via iron chelator-induced autophagic cell death and apoptosis was possible with DFO treatment. These findings provide a solid basis for targeting mitochondria iron metabolism in cisplatin-resistant NSCLC for therapeutic purposes, and it is plausible to consider that DFO facilitates in the improvement of treatment responses in cisplatin-resistant NSCLC patients.

8.
Cell Mol Biol (Noisy-le-grand) ; 66(3): 143-148, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32538761

RESUMO

The current experiment was performed to investigate the effect of LncRNA NORAD on the sensitivity of miR-410-3p to drug resistance of osteosarcoma cells. The cisplatin-resistant cell line HOS/DDP was induced; si-NC, si-NORAD, miR-NC, miR-410-3p, pcDNA-NC, and pcDNA-NORAD were transfected into HOS/DDP cells, respectively; record as a si-NC group, si-NORAD group, miR-NC group, miR-410-3p group, pcDNA-NC group, pcDNA-NORAD group; si-NORAD was co-transfected into HOS/DDP cells with anti-miR-NC, anti-miR-410-3p, recorded as an anti-miR-NC+si-NORAD group and anti-miR-410-3p+si-NORAD group. Real-time quantitative PCR (RT-qPCR) was used to detect LncRNA NORAD, miR-410-3p and multidrug resistance protein 1 (MRP1) mRNA expression levels; Western blot was used to detect cyclin D1 (CyclinD1), MRP1, phosphorylated (p-p65), phosphorylated IкBα (p-IкBα) protein expression; cell counting kit 8 (CCK-8) was used to detect cell viability; dual luciferase report assay to detect targeting relationship between LncRNA NORAD and miR-410-3p. Compared with osteosarcoma cells HOS, the expression levels of LncRNA NORAD, MRP1 mRNA and protein in osteosarcoma resistant cells HOS/DDP were significantly increased, and miR-410-3p expression levels were significantly reduced (P<0.05). Low expression of NORAD or high expression of miR-410-3p, CyclinD1, MRP1 expression levels were significantly reduced, the cell survival rate was significantly reduced, and the half inhibitory concentration of cisplatin was significantly reduced (P<0.05). LncRNA NORAD targets and regulates miR-410-3p, and low expression of miR-410-3p can reverse the effects of low NORAD expression on HOS/DDP cell proliferation and cisplatin resistance. Low expressions of NORAD, p-p65, p-IкBα protein expression levels were significantly reduced; low expression of miR-410-3p could reverse the inhibitory effect of low NORAD expression on p-p65, p-IкBα protein expression. Inhibition of LncRNA NORAD expression can inhibit the proliferation of osteosarcoma HOS/DDP cells through targeted regulation of miR-410-3p, increasing its sensitivity to cisplatin, and it may be related to the NF-κB signaling pathway.


Assuntos
Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/genética , Resistencia a Medicamentos Antineoplásicos/genética , MicroRNAs/metabolismo , Osteossarcoma/tratamento farmacológico , Osteossarcoma/genética , RNA Longo não Codificante/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Sequência de Bases , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , MicroRNAs/genética , NF-kappa B/metabolismo , Osteossarcoma/patologia , RNA Longo não Codificante/genética , Transdução de Sinais
9.
J Environ Manage ; 252: 109667, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31627097

RESUMO

To put the brakes on global climate change, China, the world's top emitter, has established ambitious CO2 emissions reduction targets. Industry-level emissions analysis can help policymakers determine better ways to achieve mitigation targets. This study is the first to target the total-factor carbon emission performance (TCPI) of secondary and service industries. We first compile industry-level CO2 emission inventories of 25 Yangtze River Delta cities during 2007-2016. The TCPI of secondary and service industries is then estimated by the non-radial directional distance function. We then compare the TCPI of the two industries across levels, dynamics, and inequalities using a global metafrontier approach. The results show the TCPI of the service industry (0.563 in 2016) was significantly higher than that of secondary industry (0.256 in 2016), suggesting that the service industry was more carbon-friendly. The TCPI gap between the secondary and service industries narrowed over the study period. The TCPI of secondary industry showed a promising increase during 2007-2016 with an annual growth rate of 2.30%, reflecting the positive effects of the government's reforms and environmental regulations. By contrast, the service industry saw a downward trend in TCPI, decreasing by 1.68% annually, primarily because it is a newcomer to low-carbon development. TCPI inequality in secondary industry was much larger than in the service industry, suggesting that significant heterogeneity exists in secondary industry. Therefore, policymakers should implement targeted mitigation policies for secondary industry, and place decarbonising the service industry on the agenda to reverse its decreasing TCPI.


Assuntos
Poluentes Atmosféricos , Rios , Dióxido de Carbono , China , Cidades , Monitoramento Ambiental , Indústrias
10.
Nano Lett ; 17(6): 3926-3931, 2017 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-28493711

RESUMO

Octahedral Pt alloy nanocrystals (NCs) have shown excellent activities as electrocatalysts toward oxygen reduction reaction (ORR). As the activity and stability of NCs are highly dependent on their structure and the elemental distribution, it is of great importance to understand the formation mechanism of octahedral NCs and to rationally synthesize shape-controlled alloy catalysts with optimized ORR activity and stability. However, the factors controlling the structural and compositional evolution during the synthesis have not been well understood yet. Here, we systematically investigated the structure and composition evolution pathways of Pt-Ni octahedra synthesized with the assistance of W(CO)6 and revealed a unique core-shell structure consisting of a Pt core and a Pt-Ni alloy shell. Below 140 °C, sphere-like pure Pt NCs with the diameter of 3-4 nm first nucleated, followed by the isotropic growth of Pt-Ni alloy on the seeds at temperatures between 170 and 230 °C forming Pt@Pt-Ni core-shell octahedra with {111} facets. Owing to its unique structure, the Pt@Pt-Ni octahedra show an unparalleled stability during potential cycling, that is, no activity drop after 10 000 cycles between 0.6 and 1.0 V. This work proposes the Pt@Pt-Ni octahedra as a high profile electrocatalyst for ORR and reveals the structural and composition evolution pathways of Pt-based bimetallic NCs.

11.
Protein Cell ; 3(11): 875-82, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23143873

RESUMO

Neural stem cells and neural progenitor cells (NPCs) exist throughout life and are mobilized to replace neurons, astrocytes and oligodendrocytes after injury. Stromal cell-derived factor 1 (SDF-1, now named CXCL12) and its receptor CXCR4, an α-chemokine receptor, are critical for NPC migration into damaged areas of the brain. Our previous studies demonstrated that immune activated and/or HIV-1-infected human monocyte-derived-macrophages (MDMs) induced a substantial increase of SDF-1 production by human astrocytes. However, matrix metalloproteinase (MMP)-2, a protein up-regulated in HIV-1-infected macrophages, is able to cleave four amino acids from the N-terminus of SDF-1, resulting in a truncated SDF-1(5-67). In this study, we investigate the diverse signaling and function induced by SDF-1α and SDF-1(5-67) in human cortical NPCs. SDF-1(5-67) was generated by incubating human recombinant SDF-1α with MMP-2 followed by protein determination via mass spectrometry, Western blotting and ELISA. SDF-1α induced time-dependent phosphorylation of extracellular signal-regulated kinases (ERK) 1/2, Akt-1, and diminished cyclic adenosine monophosphate (cAMP). In contrast, SDF-1(5-67) failed to induce these signaling. SDF-1α activation of CXCR4 induced migration of NPCs, an effect that is dependent on ERK1/2 and Akt-1 pathways; whereas SDF-1(5-67) failed to induce NPC migration. This observation provides evidence that MMP-2 may affect NPC migration through post-translational processing of SDF-1α.


Assuntos
Quimiocina CXCL12/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Células-Tronco Neurais/citologia , Receptores CXCR4/metabolismo , Movimento Celular , Células Cultivadas , AMP Cíclico/metabolismo , Humanos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Células-Tronco Neurais/metabolismo , Fosforilação , Proteólise , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
12.
Phys Rev Lett ; 109(25): 253604, 2012 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-23368462

RESUMO

Entangled states of light including low-loss optical fiber transmission and atomic resonance frequencies are essential resources for future quantum information networks. We present the experimental achievement on the three-color entanglement generation at 852, 1550, and 1440 nm wavelengths for optical continuous variables. The entanglement generation system consists of two cascaded nondegenerated optical parametric oscillators (NOPOs). The flexible selectivity of nonlinear crystals in the two NOPOs and the tunable property of NOPO provide large freedom for the frequency selection of three entangled optical beams. The presented system will hopefully be developed as a practical entangled source to be used in quantum-information networks with atomic storage units and long fiber transmission lines.

13.
J Neurosci Res ; 82(3): 295-305, 2005 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16180223

RESUMO

Neural stem/progenitor cells (NPCs) are present in the developing and adult central nervous system. NPC apoptosis is an important aspect of normal brain development. We show that tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) receptor 2 is highly expressed on human NPCs derived from fetal cortex, yet TRAIL induces only minimal levels of apoptosis in NPCs. Caspase-8 mRNA and protein, an important factor in the TRAIL-mediated death pathway, is present at low levels in human NPCs. In contrast, inhibitors of apoptosis proteins (IAP), such as c-IAP1, are highly expressed. The transcription inhibitor actinomycin D sensitized human NPCs to TRAIL-induced apoptosis. Further, inhibition of cellular inhibitors of apoptosis protein 1 (c-IAP1) expression by small interfering RNA (siRNA) increased TRAIL-mediated caspase-3 activation and apoptosis; thus, c-IAP1 protects NPCs against TRAIL-induced apoptosis and suppresses caspase-3 activation. These findings illustrate the mechanisms for NPC resistance to apoptotic agonists such as TRAIL, and demonstrate a potentially important mechanism in CNS disease states.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Apoptose/fisiologia , Encéfalo/embriologia , Proteínas Inibidoras de Apoptose/metabolismo , Glicoproteínas de Membrana/metabolismo , Neurônios/metabolismo , Células-Tronco/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Caspase 3 , Caspase 8 , Caspases/genética , Células Cultivadas , Córtex Cerebral/embriologia , Córtex Cerebral/crescimento & desenvolvimento , Córtex Cerebral/metabolismo , Dactinomicina/farmacologia , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/genética , Feto , Humanos , Degeneração Neural/metabolismo , Degeneração Neural/fisiopatologia , Inibidores da Síntese de Proteínas/farmacologia , Interferência de RNA/fisiologia , RNA Mensageiro/metabolismo , Receptores do Ligante Indutor de Apoptose Relacionado a TNF , Receptores do Fator de Necrose Tumoral/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF , Ubiquitina-Proteína Ligases , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
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