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1.
Nano Lett ; 24(1): 378-385, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38117785

RESUMO

In self-intercalated two-dimensional (ic-2D) materials, understanding the local chemical environment and the topology of the filling site remains elusive, and the subsequent correlation with the macroscopically manifested physical properties has rarely been investigated. Herein, highly crystalline gram-scale ic-2D Ta1.33S2 crystals were successfully grown by the high-pressure high-temperature method. Employing combined atomic-resolution scanning transmission electron microscopy annular dark field imaging and density functional theory calculations, we systematically unveiled the atomic structures of an atlas of stacking registries in a well-defined √3(a) × âˆš3(a) Ta1.33S2 superlattice. Ferromagnetic order was observed in the AC' stacking registry, and it evolves into an antiferromagnetic state in AA/AB/AB' stacking registries; the AA' stacking registry shows ferrimagnetic ordering. Therefore, we present a novel approach for fabricating large-scale highly crystalline ic-2D crystals and shed light on a powerful means of modulating the magnetic order of ic-2D systems via stacking engineering, i.e., stackingtronics.

2.
Ann Hematol ; 103(9): 3657-3665, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38494553

RESUMO

Minimal residual disease (MRD) based risk stratification criteria for specific genetic subtypes remained unclear in childhood acute lymphoblastic leukemia (ALL). Among 723 children with newly diagnosed ALL treated with the Chinese Children Leukemia Group CCLG-2008 protocol, MRD was assessed at time point 1 (TP1, at the end of induction) and TP2 (before consolidation treatment) and the MRD levels significantly differed in patients with different fusion genes or immunophenotypes (P all < 0.001). Moreover, the prognostic impact of MRD varied by distinct molecular subtypes. We stratified patients in each molecular subtype into two MRD groups based on the results. For patients carrying BCR::ABL1 or KMT2A rearrangements, we classified patients with MRD < 10-2 at both TP1 and TP2 as the low MRD group and the others as the high MRD group. ETV6::RUNX1+ patients with TP1 MRD < 10-3 and TP2 MRD-negative were classified as the low MRD group and the others as the high MRD group. For T-ALL, We defined children with TP1 MRD ≥ 10-3 as the high MRD group and the others as the low MRD group. The 10-year relapse-free survival of low MRD group was significantly better than that of high MRD group. We verified the prognostic impact of the subtype-specific MRD-based stratification in patients treated with the BCH-ALL2003 protocol. In conclusion, the subtype-specific MRD risk stratification may contribute to the precise treatment of childhood ALL.


Assuntos
Neoplasia Residual , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Criança , Masculino , Feminino , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Pré-Escolar , Adolescente , Lactente , Prognóstico , Proteínas de Fusão Oncogênica/genética , Intervalo Livre de Doença
3.
Pediatr Blood Cancer ; 71(9): e31099, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38845144

RESUMO

BACKGROUND: The clinical relevance of BRAF-V600E alleles in peripheral blood mononuclear cells (PBMCs) and the prognostic impact of the mutants in cell-free (cf) and PBMC DNAs of Langerhans cell histiocytosis (LCH) have not been fully clarified in pediatric LCH. METHODS: We retrospectively determined the levels of BRAF-V600E mutation in paired plasma and PBMC samples at the time of diagnosis of LCH. Subsequently, we performed a separate or combined analysis of the clinical and prognostic impact of the mutants. RESULTS: We assessed BRAF-V600E mutation in peripheral blood from 94 patients of childhood LCH. Our data showed that cfBRAF-V600E was related to young age, multiple-system (MS) disease, involvements of organs with high risk, increased risk of relapse, and worse progression-free survival (PFS) of patients. We also observed that the presence of BRAF-V600E in PBMCs at baseline was significantly associated with MS LCH with risk organ involvement, younger age, and disease progression or relapse. The coexisting of plasma(+)/PBMC(+) identified 36.2% of the patients with the worst outcome, and the hazard ratio was more significant than either of the two alone or neither, indicating that combined analysis of the mutation in plasma and PBMCs was more accurate to predict relapse than evaluation of either one. CONCLUSIONS: Concurrent assessment of BRAF-V600E mutation in plasma and PBMCs significantly impacted the prognosis of children with LCH. Further prospective studies with larger cohorts need to validate the results of this study.


Assuntos
Histiocitose de Células de Langerhans , Leucócitos Mononucleares , Mutação , Proteínas Proto-Oncogênicas B-raf , Humanos , Histiocitose de Células de Langerhans/genética , Histiocitose de Células de Langerhans/mortalidade , Histiocitose de Células de Langerhans/patologia , Histiocitose de Células de Langerhans/terapia , Histiocitose de Células de Langerhans/tratamento farmacológico , Histiocitose de Células de Langerhans/sangue , Proteínas Proto-Oncogênicas B-raf/genética , Masculino , Feminino , Estudos Retrospectivos , Criança , Pré-Escolar , Prognóstico , Leucócitos Mononucleares/patologia , Leucócitos Mononucleares/metabolismo , Lactente , Adolescente , Seguimentos , Taxa de Sobrevida
4.
J Am Chem Soc ; 145(20): 11074-11084, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37159564

RESUMO

Two-dimensional (2D) rare-earth oxyhalides (REOXs) with novel properties offer fascinating opportunities for fundamental research and applications. The preparation of 2D REOX nanoflakes and heterostructures is crucial for revealing their intrinsic properties and realizing high-performance devices. However, it is still a great challenge to fabricate 2D REOX using a general approach. Herein, we design a facile strategy to prepare 2D LnOCl (Ln = La, Pr, Nd, Sm, Eu, Gd, Tb, Dy) nanoflakes using the molten salt method assisted by the substrate. A dual-driving mechanism was proposed in which the lateral growth could be guaranteed by the quasi-layered structure of LnOCl and the interaction between the nanoflakes and the substrate. Furthermore, this strategy has also been successfully applied for block-by-block epitaxial growth of diverse lateral heterostructures and superlattice. More significantly, the high performance of MoS2 field-effect transistors with LaOCl nanoflake as the gate dielectric was demonstrated, exhibiting competitive device characteristics of high on/off ratios up to 107 and low subthreshold swings down to 77.1 mV dec-1. This work offers a deep understanding of the growth of 2D REOX and heterostructures, shedding new light on the potential applications in future electronic devices.

5.
Nano Lett ; 22(3): 1242-1250, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35061398

RESUMO

Two-dimensional (2D) magnetic materials have attracted significant attention for promising applications in energy-saving logic and robust memory devices. However, most 2D magnets discovered so far typically feature drawbacks for practical applications due to low critical temperatures. Herein, we synthesize ultrathin room-temperature (RT) magnetic Fe7Se8 nanoflakes via the space-confined chemical vapor deposition method. It is found that the appropriate supply and control of Se concentration in the reaction chamber is crucial for synthesizing high-quality nonstoichiometric Fe7Se8 nanoflakes. Cryogenic electrical and magnetic characterizations reveal the emergence of spin reorientation at ∼130 K and the survival of long-range magnetic ordering up to room temperature. The RT magnetic domain structures with different thicknesses are also uncovered by magnetic force microscopy. Moreover, theoretical calculations confirm the spin configuration and metallic band structure. The outstanding characteristics exhibited by Fe7Se8 nanoflakes, including RT magnetism, spin reorientation property, and good electrical conductivity, make them a potential candidate for RT spintronics.

6.
J Am Chem Soc ; 144(43): 19758-19769, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36257067

RESUMO

Rare earth chalcogenides (RECs) with novel luminescence and magnetic properties offer fascinating opportunities for fundamental research and applications. However, controllable synthesis of RECs down to the two-dimensional (2D) limit still has a great challenge. Herein, 2D wedge-shaped ferromagnetic EuS single crystals are successfully synthesized via a facile molten-salt-assisted chemical vapor deposition method on sapphire. Based on the theoretical simulations and experimental measurements, the mechanisms of aligned growth and wedge-shaped growth are systematically proposed. The wedge-shaped growth is driven by a dual-interaction mechanism, where the coupling between EuS and the substrate steps impedes the lateral growth, and the strong bonding of nonlayered EuS itself facilitates the vertical growth. Through temperature-dependent Raman and photoluminescence characterization, the nanoflakes show a large Raman temperature coefficient of -0.030 cm-1 K-1 and uncommon increasing band gap with temperature. More importantly, by low-temperature magnetic force microscopy characterization, thickness variation of the magnetic signal is revealed within one sample, indicating the great potential of the wedge-shaped nanoflake to serve as a platform for highly efficient investigation of thickness-dependent magnetic properties. This work sheds new light on 2D RECs and will offer a deep understanding of 2D wedge-shaped materials.

7.
Int J Phytoremediation ; 24(8): 842-854, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34651532

RESUMO

The plants Feicai (Sedum aizoon L.) and dandelion(Taraxacum mongolicum Hand.-Mazz.) have good salt tolerance, and can improve soil quality and the micro-ecological environment. Coastal saline-soil plots planted with S. aizoon and T. mongolicum and bare plots were used to explore their effects on the microbial community structure of coastal saline soil. The diversity and function of soil bacterial communities were analyzed using Illumina MiSeq high-throughput sequencing technology. The results showed that the α-diversity of soil bacterial communities were higher in planted than in bare plots, in the following order: T. mongolicum plot > S. aizoon plot > bare plot. The soil bacterial communities also changed after planting S. aizoon and T. mongolicum. The LDA effect size analysis showed that there were 37 indicator species among the three plot types. Correlation analysis of environmental factors showed that EC, AP, and OM were the main factors influencing bacterial community composition in this coastal saline soil. The PICRUSt functional prediction showed that the numbers of metabolic functions of bacterial communities were in the following order: T. mongolicum plot > S. aizoon plot > bare plot. The results provide a theoretical basis and plant species for developing salt-tolerant bacterial resources and phytoremediation of coastal saline soil.


This study investigated the changes of soil bacterial α-diversity and community structures in coastal saline soil after planting the medicinal and edible plants coastal feicai (Sedum aizoon L.)and dandelion "Binpu No. 1" (Taraxacum mongolicum Hand.-Mazz.). It also identified the biomarkers and differential metabolic functions of soils among different plots. Our findings revealed that planting S. aizoon and T. mongolicum significantly improved bacterial diversity, and altered composition and metabolic function in coastal saline soils. This study makes a significant contribution to the literature because it offers an insight into novel strategies for vegetation restoration and ecological reconstruction of saline soils.


Assuntos
Microbiota , Solo , Bactérias/genética , Biodegradação Ambiental , China , Plantas Tolerantes a Sal , Solo/química , Microbiologia do Solo
8.
Nano Lett ; 21(21): 9318-9324, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34677980

RESUMO

Nonvolatile reconfigurable transistors can be used to implement highly flexible and compact logic circuits with low power consumption in maintaining the configuration. In this paper, we build nonvolatile reconfigurable transistors based on 2D CuInP2S6/MoTe2 heterostructures. The ferroelectric polarization-induced electron and hole doping in the heterostructure are investigated. By introducing the ferroelectric doping into the source/drain contacts, we demonstrate reconfigurable Schottky barrier transistors, whose polarity (n-type or p-type) can be dynamically programmed, where the configuration is nonvolatile in nature. These transistors exhibit a tunable photoresponse, where the n-n doping state leads to negative photocurrent, whereas the p-p doping state gives rise to a positive photocurrent. The transistor with asymmetric (n-p or p-n) contacts exhibits a strong photovoltaic effect. These reconfigurable logic and optoelectronic transistors will enable a new type of device fabric for future computing systems and sensing networks.

9.
Int J Mol Sci ; 23(10)2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35628477

RESUMO

Rice blast is one of the main diseases in rice and can occur in different rice growth stages. Due to the complicated procedure of panicle blast identification and instability of panicle blast infection influenced by the environment, most cloned rice resistance genes are associated with leaf blast. In this study, a rice panicle blast resistance gene, Pb2, was identified by genome-wide association mapping based on the panicle blast resistance phenotypes of 230 Rice Diversity Panel 1 (RDP1) accessions with 700,000 single-nucleotide polymorphism (SNP) markers. A genome-wide association study identified 18 panicle blast resistance loci (PBRL) within two years, including 9 reported loci and 2 repeated loci (PBRL2 and PBRL13, PBRL10 and PBRL18). Among them, the repeated locus (PBRL10 and PBRL18) was located in chromosome 11. By haplotype and expression analysis, one of the Nucleotide-binding domain and Leucine-rich Repeat (NLR) Pb2 genes was highly conserved in multiple resistant rice cultivars, and its expression was significantly upregulated after rice blast infection. Pb2 encodes a typical NBS-LRR protein with NB-ARC domain and LRR domain. Compared with wild type plants, the transgenic rice of Pb2 showed enhanced resistance to panicle and leaf blast with reduced lesion number. Subcellular localization of Pb2 showed that it is located on plasma membrane, and GUS tissue-staining observation found that Pb2 is highly expressed in grains, leaf tips and stem nodes. The Pb2 transgenic plants showed no difference in agronomic traits with wild type plants. It indicated that Pb2 could be useful for breeding of rice blast resistance.


Assuntos
Magnaporthe , Oryza , Resistência à Doença/genética , Estudo de Associação Genômica Ampla , Chumbo/metabolismo , Magnaporthe/genética , Proteínas NLR/metabolismo , Nucleotídeos/metabolismo , Oryza/genética , Oryza/metabolismo , Melhoramento Vegetal , Doenças das Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
10.
Zhongguo Zhong Yao Za Zhi ; 40(11): 2221-6, 2015 Jun.
Artigo em Zh | MEDLINE | ID: mdl-26552185

RESUMO

To study the toxicokinetics of bakuchiol, hepatic and renal toxicity in rats after single oral administration of Psoraleae Fructus and combined with Glycyrrhizae Radix et Rhizoma, in order to provide scientific evidences for clinical safe medication use. A total of 35 SD rats were randomly divided into seven groups: vehicle (distilled water) control group, Glycyrrhizae Radix et Rhizoma group, positive control (aristolochic acid A) group, Psoraleae Fructus (40 g x kg(-1)) group( both male and female rats), Psoraleae Fructus and Glycyrrhizae Radix et Rhizoma (40 +20) g x kg(-1) group (both male and female rats). HPLC-UV method was used to determine the concentration of bakuchiol in rat plasma at different time points after single oral administration. Plasma alanine transaminase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), plasma creatinine (Cr), N-acetyl-ß-D-glucosaminidase (NAG) and kidney injury molecule 1 (Kim-1) were measured after administration for 24 h. The main toxicokinetics parameters of bakuchiol in rats exert significantly gender difference. When Psoraleae Fructus combination with Glycyrrhizae Radix et Rhizoma, the total area under the plasma concentration-time curve( AUC), C(max), and plasma clearance (CL) of bakuchiol were increased, respectively; CL, half-life (t½) were decreased, and T(max) were prolonged. The biochemical indicators (including ALT, AST, BUN, Cr and KIM-1 level) in different dose of Psoraleae Fructus groups, were found no statistically significant difference when compared with vehicle control group. The level of NAG in both Psoraleae Fructus and compatibility with Glycyrrhizae Radix et Rhizoma groups were significant increased (P < 0.05). There are obvious effects on toxicokinetics of bakuchiol in rats when Psoraleae Fructus combined with Glycyrrhizae Radix et Rhizoma. Renal toxicity induced by Psoraleae Fructus at high dose was observed after single oral administration and no liver damage in rats was found.


Assuntos
Glycyrrhiza/toxicidade , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fenóis/toxicidade , Psoralea/toxicidade , Administração Oral , Animais , Feminino , Masculino , Fenóis/farmacocinética , Ratos , Ratos Sprague-Dawley , Rizoma/toxicidade , Toxicocinética
11.
ACS Nano ; 18(4): 2763-2771, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38232763

RESUMO

As a promising alternative to the von Neumann architecture, in-memory computing holds the promise of delivering a high computing capacity while consuming low power. In this paper, we show that the ferroelectric reconfigurable transistor can serve as a versatile logic-in-memory unit that can perform logic operations and data storage concurrently. When functioning as memory, a ferroelectric reconfigurable transistor can implement content-addressable memory (CAM) with a 1-transistor-per-bit density. With the switchable polarity of the ferroelectric reconfigurable transistor, XOR/XNOR-like matching operation in CAM is realized in a single transistor, which can offer a significant improvement in area and energy efficiency compared to conventional CAMs. NAND- and NOR-arrays of CAMs are also demonstrated, which enable multibit matching in a single reading operation. In addition, the NOR array of CAM cells effectively measures the Hamming distance between the input query and the stored entries. When functioning as a logic element, a ferroelectric reconfigurable transistor can be switched between n- and p-type modes. Utilizing the switchable polarity of these ferroelectric Schottky barrier transistors, we demonstrate reconfigurable logic gates with NAND/NOR dual functions, whose input-output mapping can be transformed in real time without changing the layout, and the configuration is nonvolatile.

12.
Lab Anim ; 58(1): 52-64, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37702462

RESUMO

To understand the epizootiologic characteristics of pathogens and opportunistic infections in one Beagle dog production colony and three research facilities, viruses and mycoplasma were detected in 1777 samples collected from Beagle dogs in China by polymerase chain reaction/reverse transcription polymerase chain reaction, and bacteria were isolated and identified by 16S rRNA sequence analysis. In addition, genotyping of the major circulating viruses was carried out by amplification of gene fragments and homology analysis. Canine coronavirus (CCoV), Escherichia coli, canine parvovirus (CPV), Bordetella bronchiseptica, Clostridium perfringens, Mycoplasma cynos, Klebsiella pneumoniae, Streptococcus canis, canine astrovirus (CaAstV), canine kobuvirus (CaKV), Pseudomonas aeruginosa, Proteus mirabilis, Macrococcus canis, Pasteurella canis, canine bocavirus (CBoV) and canine adenovirus (CAdV) were detected in the samples. Single, double, triple and quadruple infections accounted for 6.6%, 1.4%, 1.2% and 0.96% of samples, respectively. CCoV strains in 81 samples included three genotypes, CCoV-I, CCoV-IIa and CCoV-IIb, by analysis of S gene. The rate of single infection of CCoV-I, CCoV-IIa or CCoV-IIb was 19%, 38% or 7.4% respectively. The double and triple infection rates of CCoV were 32.8% and 2.5% respectively. All CPV strains in 36 samples belonged to CPV-2c. There were three amino acid differences in the Fiber protein of CAdV-positive sample QD2022, compared with the reference strain Toronto A26/61 and the vaccine strain YCA-18. These results suggest that CCoV and CPV are primary infectious agents, and that these two viruses were often identified in mixed infections, or coinfections alongside mycoplasma or other bacteria. These results will provide the basis for improvements in prevention and control of naturally occurring infectious diseases in Beagle dog production colonies and research facilities.


Assuntos
Infecções por Coronavirus , Coronavirus Canino , Doenças do Cão , Parvovirus Canino , Cães , Animais , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , RNA Ribossômico 16S/genética , Doenças do Cão/epidemiologia , Reação em Cadeia da Polimerase , China/epidemiologia , Coronavirus Canino/genética , Parvovirus Canino/genética
13.
J Pediatr (Rio J) ; 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39265632

RESUMO

OBJECTIVE: Langerhans cell histiocytosis (LCH) is a rare myeloid neoplasm with inflammatory characteristics. This study aims to investigate the correlation between sCD25 levels and clinical characteristics, as well as prognosis, in pediatric LCH. METHODS: Serum sCD25 levels were measured in 370 LCH patients under 18 years old using ELISA assays. The patients were divided into two cohorts based on different treatment regimens. We further assessed the predictive value for the prognosis impact of sCD25 in a test cohort, which was validated in the independent validation cohort. RESULTS: The median serum sCD25 level at diagnosis was 3908 pg/ml (range: 231-44 000pg/ml). sCD25 level was significantly higher in multi-system and risk organ positive (MS RO+) LCH patients compared to single-system(SS) LCH patients (p < 0.001). Patients with elevated sCD25 were more likely to have involvement of risk organs, skin, lung, lymph nodes, or pituitary (all p < 0.05). sCD25 level could predict LCH progression and relapse, with an area under the ROC curve of 60.6 %. The optimal cutoff value was determined at 2921 pg/ml. Patients in the high-sCD25 group had significantly worse progression-free survival compared to those in the low-sCD25 group (p < 0.05). CONCLUSION: Elevated serum sCD25 level at initial diagnosis was associated with high-risk clinical features and worse prognosis. sCD25 level can predict the progression/recurrence of LCH following first-line chemotherapy.

14.
BMC Psychol ; 11(1): 276, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37715275

RESUMO

BACKGROUND: What is our immediate reaction when we witness someone experiencing pain? The empathy-altruism hypothesis predicts that observers would display empathy and a tendency to approach the person in pain. Alternatively, the threat value of pain hypothesis (TVPH) argues that others' pain serves as a signal of threat and should induce observers' avoidance response. METHODS: To examine these two hypotheses, three experiments were conducted. The experiments aimed to investigate the impact of subliminal exposure to others' physical pain on participants' emotional and behavioural responses. RESULTS: The results revealed that subliminal pain priming resulted in faster response and attentional bias to fearful faces compared to sad faces (Experiment 1), faster reaction times in recognizing fear-related words compared to anger-related words during a lexical decision task (Experiment 2), and faster avoidance responses towards anger-related words, as opposed to approaching responses towards positive words (Experiment 3). CONCLUSIONS: The consistent findings across all experiments revealed that subliminal perception of pain scenes elicited fear emotion and immediate avoidance responses. Therefore, the outcomes of our study provide supportive evidence for the TVPH.


Assuntos
Empatia , Estimulação Subliminar , Humanos , Emoções , Medo , Dor
15.
ACS Appl Mater Interfaces ; 15(46): 53671-53677, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37947841

RESUMO

In this paper, we demonstrate low-thermal-budget ferroelectric field-effect transistors (FeFETs) based on the two-dimensional ferroelectric CuInP2S6 (CIPS) and oxide semiconductor InZnO (IZO). The CIPS/IZO FeFETs exhibit nonvolatile memory windows of ∼1 V, low off-state drain currents, and high carrier mobilities. The ferroelectric CIPS layer serves a dual purpose by providing electrostatic doping in IZO and acting as a passivation layer for the IZO channel. We also investigate the CIPS/IZO FeFETs as artificial synaptic devices for neural networks. The CIPS/IZO synapse demonstrates a sizable dynamic ratio (125) and maintains stable multilevel states. Neural networks based on CIPS/IZO FeFETs achieve an accuracy rate of over 80% in recognizing MNIST handwritten digits. These ferroelectric transistors can be vertically stacked on silicon complementary metal-oxide semiconductor (CMOS) with a low thermal budget, offering broad applications in CMOS+X technologies and energy-efficient 3D neural networks.

16.
Nat Commun ; 14(1): 958, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36810290

RESUMO

Two-dimensional (2D) nonlayered materials have recently provoked a surge of interest due to their abundant species and attractive properties with promising applications in catalysis, nanoelectronics, and spintronics. However, their 2D anisotropic growth still faces considerable challenges and lacks systematic theoretical guidance. Here, we propose a general thermodynamics-triggered competitive growth (TTCG) model providing a multivariate quantitative criterion to predict and guide 2D nonlayered materials growth. Based on this model, we design a universal hydrate-assisted chemical vapor deposition strategy for the controllable synthesis of various 2D nonlayered transition metal oxides. Four unique phases of iron oxides with distinct topological structures have also been selectively grown. More importantly, ultra-thin oxides display high-temperature magnetic ordering and large coercivity. MnxFeyCo3-x-yO4 alloy is also demonstrated to be a promising room-temperature magnetic semiconductor. Our work sheds light on the synthesis of 2D nonlayered materials and promotes their application for room-temperature spintronic devices.

17.
Sci Adv ; 9(49): eadj3955, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38064554

RESUMO

The discovery of magnetism in van der Waals (vdW) materials has established unique building blocks for the research of emergent spintronic phenomena. In particular, owing to their intrinsically clean surface without dangling bonds, the vdW magnets hold the potential to construct a superior interface that allows for efficient electrical manipulation of magnetism. Despite several attempts in this direction, it usually requires a cryogenic condition and the assistance of external magnetic fields, which is detrimental to the real application. Here, we fabricate heterostructures based on Fe3GaTe2 flakes that have room-temperature ferromagnetism with excellent perpendicular magnetic anisotropy. The current-driven nonreciprocal modulation of coercive fields reveals a high spin-torque efficiency in the Fe3GaTe2/Pt heterostructures, which further leads to a full magnetization switching by current. Moreover, we demonstrate the field-free magnetization switching resulting from out-of-plane polarized spin currents by asymmetric geometry design. Our work could expedite the development of efficient vdW spintronic logic, memory, and neuromorphic computing devices.

18.
Front Public Health ; 10: 917581, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36249242

RESUMO

COVID-19 caused harmful mental consequences to the public, and mental health problems were very common among college students during the outbreak of COVID-19. Academic stressors were the main stress for college students, and social support, social well-being, and self-identity were widely known as protective factors for mental health. Therefore, the study aimed to investigate the influence of academic stressors on mental health and the mediating effect of social support, social well-being, and self-identity among college students during the outbreak of COVID-19. With 900 college students as subjects, using the college students' academic stressors questionnaire, social support questionnaire, social well-being scale, self-identity scale, and depression anxiety stress scales (DASS-21), the results showed that: (1) academic stressors had a significantly negative correlation with social support, social well-being, and self-identity while having a significantly positive correlation with mental health; (2) academic stressors could positively predict mental health; (3) this effect was mediated by social support, social well-being, and self-identity; (4) work stressor was an important stressor during COVID-19, and had the same role as academic stressors in the structural equation model. The results of this study suggested that adjusting the academic stressors or work stressors of college students and enhancing social support could improve social well-being and self-identity, and might effectively protect their mental health under the COVID-19 pandemic environment.


Assuntos
COVID-19 , COVID-19/epidemiologia , Humanos , Saúde Mental , Pandemias , Apoio Social , Estudantes/psicologia
19.
Chemosphere ; 296: 134000, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35192852

RESUMO

The extensive use of graphene oxide (GO) has resulted in its inevitable entry into the environment. It has been established that GO is detrimental to nitrogen accumulation in plants, as nitrogen is one of the most important nutrient for plant growth. However, its influence on nitrogen assimilation has not yet been investigated comprehensively. Based on the analysis of transcriptomics and nitrogen metabolites, this study showed that 400 mg L-1 GO exposure downregulated most of the genes encoding nitrogen-assimilating enzymes, including nitrate reductase (NR), glutamine synthetase (GS), glutamate synthase (GOGAT), and glutamate dehydrogenase (GDH). The activities of the above enzymes in wheat roots were also reduced with GO addition, and the activities of NR and GS, the rate-limiting enzymes of nitrate and ammonium assimilation, were approximately 75% and 76% lower with 400 mg L-1 GO supply, respectively, compared to those upon control treatment. Correspondingly, GO appears to exert a negative effect on multiple nitrogen assimilation products, including nitrous nitrogen, ammonium nitrogen, glutamine, glutamate, and soluble protein. In summary, this study showed that GO has adverse effects on the nitrogen assimilation of plants, and NR and GS are the most affected sites. Our findings would provide deeper insights into the physiological and molecular mechanisms underlying GO phytotoxicity.


Assuntos
Compostos de Amônio , Grafite , Nitrogênio , Compostos de Amônio/metabolismo , Glutamato-Amônia Ligase/genética , Glutamato-Amônia Ligase/metabolismo , Nitrato Redutase/genética , Nitrato Redutase/metabolismo , Nitrogênio/metabolismo , Plantas/metabolismo , Transcriptoma , Triticum/genética , Triticum/metabolismo
20.
Adv Healthc Mater ; 11(21): e2201240, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36065620

RESUMO

Triple-negative breast cancer (TNBC) as "cold" tumor is characterized by severe immunosuppression of the tumor microenvironment (TME). To effectively activate the immune response of TNBC, a new kind of therapy strategy called cancer catalytic immunotherapy is proposed based on magnetic nanoparticles (NPs) as immune activators. Utilizing the weak acidity and excessive hydrogen peroxide of TME, these magnetic NPs can release ferrous ions to promote Fenton reaction, leading to abundant ·OH and reactive oxygen species (ROS) for ultimately killing cancer cells. Mechanistically, these magnetic NPs activate the ROS-related signaling pathway to generate more ROS. Meanwhile, these magnetic NPs with unique immunological properties can promote the maturation of dendritic cells and the polarization of macrophages from M2 to M1, resulting in the infiltration of more T cells to reprogram the immunoecology of TNBC from "cold" to "hot" state. Besides directly affecting immune cells, these magnetic NPs can also affect the secretion of some immune-related cytokines by cancer cells, to further indirectly activate the immune response. In conclusion, these catalytic immune activators are designed to achieve the synergistic treatment of chemodynamic therapy-enhanced immunotherapy guided by computed tomography (CT)/near-infrared region-II (NIR-II) dual-mode imaging, providing a new strategy for TNBC treatment.


Assuntos
Nanopartículas de Magnetita , Nanopartículas , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/patologia , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Magnetismo , Microambiente Tumoral
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