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1.
J Hazard Mater ; 470: 134301, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38626681

RESUMEN

Carbendazim residue has been widely concerned, and nitrous oxide (N2O) is one of the dominant greenhouse gases. Microbial metabolisms are fundamental processes of removing organic pollutant and producing N2O. Nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) can change soil abiotic properties and microbial communities and simultaneously affect carbendazim degradation and N2O emission. In this study, the comprehensive linkages among carbendazim residue, N2O emission and microbial community after the DMPP application were quantified under different soil moistures. Under 90% WHC, the DMPP application significantly reduced carbendazim residue by 54.82% and reduced soil N2O emission by 98.68%. The carbendazim residue was negatively related to soil ammonium nitrogen (NH4+-N), urease activity, and ratios of Bacteroidetes, Thaumarchaeota and Nitrospirae under 90% WHC, and the N2O emission was negatively related to NH4+-N content and relative abundance of Acidobacteria under the 60% WHC condition. In the whole (60% and 90% WHC together), the carbendazim residue was negatively related to the abundances of nrfA (correlation coefficient = -0.623) and nrfH (correlation coefficient = -0.468) genes. The hao gene was negatively related to the carbendazim residue but was positively related to the N2O emission rate. The DMPP application had the promising potential to simultaneously reduce ecological risks of fungicide residue and N2O emission via altering soil abiotic properties, microbial activities and communities and functional genes. ENVIRONMENTAL IMPLICATION: Carbendazim was a high-efficiency fungicide that was widely used in agricultural production. Nitrous oxide (N2O) is the third most important greenhouse gas responsible for global warming. The 3, 4-dimethylpyrazole phosphate (DMPP) is an effective nitrification inhibitor widely used in agricultural production. This study indicated that the DMPP application reduced soil carbendazim residues and N2O emission. The asymmetric linkages among the carbendazim residue, N2O emission, microbial community and functional gene abundance were regulated by the DMPP application and soil moisture. The results could broaden our horizons on the utilizations DMPP in decreasing fungicide risks and N2O emission.


Asunto(s)
Carbamatos , Fungicidas Industriales , Microbiota , Nitrificación , Óxido Nitroso , Pirazoles , Microbiología del Suelo , Contaminantes del Suelo , Óxido Nitroso/análisis , Contaminantes del Suelo/análisis , Microbiota/efectos de los fármacos , Bencimidazoles , Suelo/química , Bacterias/genética , Bacterias/metabolismo , Bacterias/efectos de los fármacos , Bacterias/clasificación , Agua/química
2.
bioRxiv ; 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38659777

RESUMEN

Within multicellular living systems, cells coordinate their positions with spatiotemporal accuracy to form various structures, setting the clock to control developmental processes and trigger maturation. These arrangements can be regulated by tissue topology, biochemical cues, as well as mechanical perturbations. However, the fundamental rules of how local cell packing order is regulated in forming three-dimensional (3D) multicellular architectures remain unclear. Furthermore, how cellular coordination evolves during developmental processes, and whether this cell patterning behavior is indicative of more complex biological functions, is largely unknown. Here, using human lung alveolospheres as a model system, by combining experiments and numerical simulations, we find that, surprisingly, cell packing behavior on alveolospheres resembles hard-disk packing but with increased randomness; the stiffer cell nuclei act as the hard disks surrounded by deformable cell bodies. Interestingly, we observe the emergence of topological packing order during alveolosphere growth, as a result of increasing nucleus-to-cell size ratio. Specifically, we find more hexagon-concentrated cellular packing with increasing bond orientational order, indicating a topological gas-to-liquid transition. Additionally, by osmotically changing the compactness of cells on alveolospheres, we observe that the variations in packing order align with the change of nucleus-to-cell size ratio. Together, our findings reveal the underlying rules of cell coordination and topological phases during human lung alveolosphere growth. These static packing characteristics are consistent with cell dynamics, together suggesting that better cellular packing stabilizes local cell neighborhoods and may regulate more complex biological functions such as organ development and cellular maturation.

3.
Front Plant Sci ; 15: 1297812, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38434433

RESUMEN

Introduction: The potato (Solanum tuberosum L.), one of the most vital food crops worldwide, is sensitive to salinity. Brassinosteroids (BRs) are crucial in tolerance to various abiotic stresses. The constitutive photomorphogenesis and dwarf (CPD) gene encodes C-3 oxidase, which is a rate-limiting enzyme that controls the synthesis of BRs. Methods: In this study, we used StCPD gene overexpression (T) and un-transgenic (NT) plants obtained from our former research to illustrate adaptive resistance to salt stress at levels of phenotype; cell ultrastructure, physiology, and biochemistry; hormone; and transcription. Results: Results showed the accumulation of 2,4-epibrassionolide (EBL) in T potatoes. We found that under high salt situations, the changed Na+/K+ transporter gene expression was linked with the prevalent ionic responses in T plants, which led to lower concentrations of K+ and higher concentrations of Na+ in leaves. Furthermore, RNA-sequencing (RNA-seq) data elucidated that gene expressions in NT and T plants were significantly changed with 200-mM NaCl treatment for 24 h and 48 h, compared with the 0-h treatment. Functional enrichment analysis suggested that most of the differentially expressed genes (DEGs) were related to the regulation of BR-related gene expression, pigment metabolism process, light and action, and plant hormone signal transduction. Discussion: These findings suggested that StCPD gene overexpression can alleviate the damage caused by salt stress and enhance the salt resistance of potato plantlets. Our study provides an essential reference for further research on BR regulation of plant molecular mechanisms in potatoes with stress tolerance.

4.
BMC Pulm Med ; 23(1): 424, 2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37924038

RESUMEN

BACKGROUND AND OBJECTIVE: Although chronic obstructive pulmonary disease (COPD) is a common disease leading to further morbidity and significant mortality, there is still limited data on screening for COPD. The purpose of this study was to establish an early chronic obstructive pulmonary disease (COPD) screening system for the community and hospitals in Nanshan District in Shenzhen City, to improve the rate of early diagnosis and treatment of patients with COPD. METHODS: We identified individuals at high risk of COPD using a questionnaire survey and analyzed the relevant influencing factors in the early stages of COPD in high-risk groups. RESULTS: We collected a total of 5,000 COPD screening questionnaires, and a total of 449 patients were diagnosed with COPD by pulmonary function examination. The prevalence of COPD in people aged 20 and above in Nanshan District of Shenzhen City was estimated to be 8.98%, with a base of 5000. The severity classification as per the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria was as follows: GOLD I accounted for 34.74%; GOLD II accounted for 37.64%; GOLD III accounted for 16.04%; and GOLD IV accounted for 11.58%. Common features of early COPD that we identified were: (1) patients were mainly males, accounting for 68.0%; (2) COPD was common among people aged 50-59 years, comprising 31%; (3) 96.0% of patients often had severe respiratory symptoms and had frequent coughs when they did not have a cold; (4) 57.2% of patients experienced shortness of breath when walking quickly on level ground or climbing gentle slopes; (5) 72.6% of patients had a family history of bronchial asthma and COPD. Multivariate ordinal multi-classification logistic regression showed that gender, age, shortness of breath, and the use of firewood, grass, and coal stoves were all influencing factors in pulmonary function grading. CONCLUSION: A screening questionnaire combined with a pulmonary function test should be adopted as a COPD screening strategy to be implemented at the primary level as a public health priority in China to reduce the incidence, disability, and mortality from COPD.


Asunto(s)
Asma , Enfermedad Pulmonar Obstructiva Crónica , Masculino , Humanos , Femenino , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Pulmón , Disnea/epidemiología , Disnea/etiología , Diagnóstico Precoz
5.
Sci Total Environ ; 903: 166337, 2023 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-37591394

RESUMEN

Crop yield and quality are substantial indicators of evaluating agricultural nitrogen management practices, and the nitrate (NO3--N) is one of the predominant factors affecting crop quality. The NO3--N accumulation in vegetable crop affects plant growth and quality and human health. Therefore, it is necessary to stimulate vegetable yield but eliminate excessive NO3--N in soils and plants with feasible management strategies. Graphene oxide (GO) is a novel carbon nanomaterial that has attracted great attention, but rare research has been conducted to quantify the effects of GO on plant NO3--N accumulation and microbial communities. This study explored effects of the GO and nitrification inhibitors, dicyandiamide (DCD) and 3, 4-dimethylpyrazole phosphate (DMPP), on vegetable yields and NO3--N contents and bacterial communities in soil-cabbage (Brassica rapa subsp. Chinensis) system. The soil NO3--N content was significantly reduced with the single GO application. The cabbage NO3--N content was increased by 60.4 % while the cabbage yield was significantly enhanced by 101.9 % with the single GO application. Meanwhile, the Invsimpson index of soil bacterial community and the ACE and Chao1 richness estimators of endophytic bacterial community were significantly decreased by the GO application. Cabbage NO3--N content was significantly and negatively correlated with the soil Myxococcota, endophytic bacterial community co-occurrence network edge, cabbage soluble sugar and cabbage proline. The GO application generated double-edged sword effects of positively promoting yield but causing risks of NO3--N accumulation and quality deterioration. However, these adverse effects could be mitigated by the extra nitrification inhibitor application. The potential ecological risks of GO application to the vegetable quality and endophytic community should be considered.

6.
Front Physiol ; 14: 1032786, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37008007

RESUMEN

Objective: This study explored the correlation between a Th1/Th2 cytokines imbalance and 25-hydroxy-vitamin D (vit D) level in early chronic obstructive pulmonary disease (COPD), provided experimental rationales for the role of vit D in the prevention and control of COPD, and elucidated the potential anti-inflammatory mechanism involved. Methods: This study was based on the results of the "Screening and Early Diagnosis of COPD" public health project conducted through Shenzhen Municipal Qianhai Shekou Free Trade Zone Hospital. Patients with early COPD were selected as study participants. A prospective, randomized, and controlled method was employed for assigning eligible participants into three groups, i.e., a COPD lung function (LF) I, COPD LF II, and a healthy group, respectively (n = 40 each). The serum content of tumor necrosis factor alpha (TNF-α), interferon-gamma (IFN-γ), interleukin 4 (IL-4), and IL-6 were measured by enzyme-linked immunosorbent assay, and the ratio of IFN-γ/IL-4 treated as a marker for Th1/Th2. The serum concentration of 25-hydroxyl-vit D (25 [OH]D) was quantified by a chemiluminescence assay. Statistical processing was performed, and the correlations between changes in the above parameters with vit D level and LF parameters were examined. Results: There were differences in FEV1pred%, FEV1/FVC, IFN-γ, IL-4, IL-6 and IFN-γ/IL-4 between the healthy group, the COPD LF I group and the COPD LF II group (p < 0.05). In early COPD, Th1/Th2 cytokines was positively correlated with forced expiratory volume/expected value (FEV1pred%) (r = 0.485, p < 0.001) and forced expiratory volume/forced vital capacity (FEV1/FVC) (r = 0.273, p = 0.018); Th1/Th2 cytokines levels positively correlated with vit D level (r = 0.27, p = 0.02), and 25(OH)D level positively correlated with FEV1pred% (r = 0.695, p < 0.001). Conclusion: Vitamin D deficiency was ubiquitous in patients with early COPD. It was positively correlated with the FEV1pred% and FEV1/FVC LF parameters. Accordingly, this study provides experimental rationales for the role of vit D in the prevention and control of COPD and the potential anti-inflammatory mechanisms involved.

7.
Polymers (Basel) ; 15(3)2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36771918

RESUMEN

With the improvement of protection technology, the damage power of conventional penetrators has become increasingly inferior. Reactive material is a new type of energetic material, which has strong energy release capabilities under high-velocity-impact conditions. In this paper, the reactive materials were put into the penetrator, and its penetration characteristics were studied. First, the penetrator with enhanced lateral effect (PELE) projectile structure with better penetration capability was obtained by numerical simulation. Then, based on the established polytetrafluoroethylene (PTFE)/Al reactive material reaction model, the numerical simulation and experimental research of the PELE projectile with a reactive inner core penetrating the target were carried out. The results show that the simulation results are in good agreement with the experimental results, which verifies the confidence of the numerical simulation. The PELE projectile had a significant increase in power with the use of a truncated conical head and reactive materials. The residual velocity of the truncated cone PELE projectile increases by 8.41-21% over conventional PELE projectiles. Its damage range is 43% higher than that of conventional penetrators. The simulation method and the conclusions obtained in this paper can provide support and reference for further research on reactive materials and on effectively improving the damage power of the penetrator.

8.
Materials (Basel) ; 17(1)2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38203871

RESUMEN

The high-pressure-related problems of materials constitute a field at the confluence of several scientific disciplines [...].

9.
Cell Death Discov ; 8(1): 497, 2022 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-36566230

RESUMEN

N6-methylation of adenosine (m6A) is one of the most frequent chemical modifications in eukaryotic RNAs and plays a vital role in tumorigenesis and progression. Recently, emerging studies have shown that m6A modification by ALKBH5 was associated with immunotherapy response in various types of cancer. However, whether m6A demethylases ALKBH5 participate in regulating the tumor immune microenvironment and the efficacy of immunotherapy in glioblastoma remain unknown. Here, we found that deletion of ALKBH5 significantly inhibited the growth of glioma allografts, rescued the antitumoral immune response, and increased cytotoxic lymphocyte infiltration and proinflammatory cytokines in CSF while significantly suppressing PD-L1 protein expression. m6A-methylated RNA immunoprecipitation sequencing and RNA sequencing identify ZDDHC3 as the direct target of ALKBH5. Mechanically, ALKBH5 deficiency impairs the YTHDF2-mediated stability of ZDHHC3 mRNA, thereby suppressing PD-L1 expression by accelerating PD-L1 degradation in glioma. In addition, genetic deletion or pharmacological inhibition of ALKBH5 with IOX1 enhances the therapeutic efficacy of anti-PD-1 treatment in preclinical mice models. These data suggest that the combination of anti-PD-1 therapy and ALKBH5 inhibition may be a promising treatment strategy in glioma.

10.
Clin Cardiol ; 45(12): 1246-1254, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36069119

RESUMEN

BACKGROUND AND HYPOTHESIS: Glycemic variability in one fact that explain the differences in cardiovascular outcomes. The short-term fasting plasma glucose (FPG) variability may have an on major adverse cardiovascular events (MACE) in type 2 diabetes mellitus (T2DM) patients with ST-segment elevation myocardial infarction (STEMI). METHODS: This study retrospectively analyzed T2DM patients who underwent emergent percutaneous coronary intervention (PCI) due to STEMI in Fuwai Hospital, Chinese Academy of Medical Sciences, Shenzhen, between January 2016 and March 2020. All patients underwent at least 5 FPG measurements during the perioperative period. FPG variability score (FPG-VS) was defined as the percentage of the number of FPG variations > 1 mmol/L between two adjacent FPG measurements. The Cox proportional-hazards model was used to estimate the relationship between FPG-VS and MACE. A validation set was utilized to further evaluate the prognostic value of FPG-VS in a standardized STEMI diabetic diet cohort following PCI intervention. RESULTS: A total of 612 patients were included in the retrospective cohort study. In comparison to the minimum quintile, FPG-VS > 60% was associated with an increased risk of 30-day MACE. Moreover, compared to FPG-VS ≤ 20%, the FPG-VS > 80% group had a higher risk of MACE (odd ratio [OR] = 4.87, 95% confidence interval [CI]: 2.55-5.28), recurrent angina pectoris (OR = 5.43, 95% CI: 2.27-8.27), nonfatal myocardial infarction (OR = 5.00, 95% CI: 2.47-7.69), heart failure (OR = 3.70, 95% CI: 1.92-5.54), malignant arrhythmia (OR = 4.63, 95% CI: 1.12-6.25) and cardiac death (OR = 1.41, 95% CI: 0.17-1.97). Consistent results were obtained after adjustment for HbA1c, demonstrating the robustness of FPGFPG-VS. Moreover, the standard diet intervention group had a lower FPG-VS index as well as a lower incidence of MACE. CONCLUSION: Higher FPG variability is associated with an increased risk of MACE within 30 days in diabetes patients receiving PCI for STEMI. A standardized diet may improve the prognosis of STEMI patients by reducing the FPG-VS.


Asunto(s)
Diabetes Mellitus Tipo 2 , Infarto del Miocardio , Intervención Coronaria Percutánea , Infarto del Miocardio con Elevación del ST , Humanos , Infarto del Miocardio con Elevación del ST/diagnóstico , Infarto del Miocardio con Elevación del ST/cirugía , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/métodos , Estudios Retrospectivos , Glucemia , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Infarto del Miocardio/epidemiología , Pronóstico , Ayuno , Resultado del Tratamiento
12.
Front Cardiovasc Med ; 9: 837330, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35669469

RESUMEN

Background: The present study aims to explore risk factors related to in-stent restenosis (ISR) in elderly patients with coronary heart disease and type 2 diabetes within 2 years after the first drug-eluting stent (DES) implantation. Methods: This case-control study retrospectively analyzed the clinical data of patients with coronary heart disease and diabetes undergoing percutaneous coronary intervention (PCI) in Shenzhen Sun Yat-sen Cardiovascular Hospital between January 2010 and March 2020. Univariate and multivariate models were used to assess independent factors for DES-ISR. Categorical principal component analysis of clinical variables was performed to determine important components for DES-ISR. Nomogram was constructed to quantitatively predict the probability of DES-ISR development. The diagnostic potential of clinical variables was determined by receiver operating characteristic curve. Results: In the derivation cohort, 1,741 cases were included in this study, and a total of 227 pairs of cases and controls were generated by propensity score matching. In the validation cohort, 102 cases were included with 19 cases (18.6%) with DES-ISR. Glomerular filtration rate <60 ml/min/1.73 m2, fasting blood glucose ≥6.5 mmol/L, multivessel coronary artery disease, coronary artery diffuse disease, PCI operation time (≥60 min), emergency PCI were associated with ISR. High Nomogram score was associated with the increased risk of ISR. Further analysis of the validation cohort showed that higher levels of HbA1c-coefficient of variation (CV) were significantly associated with the increased risk of ISR. HbA1c-CV exhibited good predictive ability for ISR in the validation cohort. Conclusions: In conclusion, the fasting blood glucose level during the perioperative period of emergency PCI and the long-term variation of HbA1c during the follow-up period are related to the incidence of DES-ISR and the degree of stenosis. Reducing blood glucose fluctuations may decrease the risk of DES-ISR.

13.
Front Immunol ; 13: 873382, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35720361

RESUMEN

Adiponectin (APN), a fat-derived plasma hormone, is a classic anti-inflammatory agent. Multiple studies have demonstrated the beneficial role of APN in acute brain injury, but the effect of APN in germinal matrix hemorrhage (GMH) is unclear, and the underlying molecular mechanisms remain largely undefined. In the current study, we used a GMH rat model with rh-APN treatment, and we observed that APN demonstrated a protective effect on neurological function and an inhibitory effect on neuroinflammation after GMH. To further explore the underlying mechanisms of these effects, we found that the expression of Adiponectin receptor 1 (AdipoR1) primarily colocalized with microglia and neurons in the brain. Moreover, AdiopR1, but not AdipoR2, was largely increased in GMH rats. Meanwhile, further investigation showed that APN treatment promoted AdipoR1/APPL1-mediated AMPK phosphorylation, further increased peroxisome proliferator-activated receptor gamma (PPARγ) expression, and induced microglial M2 polarization to reduce the neuroinflammation and enhance hematoma resolution in GMH rats. Importantly, either knockdown of AdipoR1, APPL1, or LKB1, or specific inhibition of AMPK/PPARγ signaling in microglia abrogated the protective effect of APN after GMH in rats. In all, we propose that APN works as a potential therapeutic agent to ameliorate the inflammatory response following GMH by enhancing the M2 polarization of microglia via AdipoR1/APPL1/AMPK/PPARγ signaling pathway, ultimately attenuating inflammatory brain injury induced by hemorrhage.


Asunto(s)
Lesiones Encefálicas , Microglía , Proteínas Quinasas Activadas por AMP/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Adiponectina/metabolismo , Adiponectina/farmacología , Animales , Animales Recién Nacidos , Lesiones Encefálicas/tratamiento farmacológico , Lesiones Encefálicas/etiología , Lesiones Encefálicas/metabolismo , Proteínas Portadoras/metabolismo , Hemorragia Cerebral/tratamiento farmacológico , Hemorragia Cerebral/metabolismo , Microglía/metabolismo , Proteínas del Tejido Nervioso/metabolismo , PPAR gamma/metabolismo , Ratas , Transducción de Señal
14.
Cancer Sci ; 113(8): 2681-2692, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35637600

RESUMEN

The discovery of long noncoding RNAs (lncRNAs) has improved the understanding of development and progression in various cancer subtypes. However, the role of lncRNAs in temozolomide (TMZ) resistance in glioblastoma multiforme (GBM) remains largely undefined. In this present study, the differential expression of lncRNAs was identified between U87 and U87 TMZ-resistant (TR) cells. lncRNA XLOC013218 (XLOC) was drastically upregulated in TR cells and was associated with poor prognosis in glioma. Overexpression of XLOC markedly increased TMZ resistance, promoted proliferation, and inhibited apoptosis in vitro and in vivo. In addition, RNA-seq analysis and gain-of-function or loss-of-function studies revealed that PIK3R2 was the potential target of XLOC. Mechanistically, XLOC recruited specificity protein 1 (Sp1) transcription factor and promoted the binding of Sp1 to the promoters of PIK3R2, which elevated the expression of PIK3R2 in both mRNA and protein levels. Finally, PIK3R2-mediated activation of the PI3K/AKT signaling pathway promoted TMZ resistance and cell proliferation, but inhibited cell apoptosis. In conclusion, these data highlight the vital role of the XLOC/Sp1/PIK3R2/PI3K/AKT axis in GBM TMZ resistance.


Asunto(s)
Neoplasias Encefálicas , Resistencia a Antineoplásicos , Glioblastoma , Glioma , Fosfatidilinositol 3-Quinasas , ARN Largo no Codificante , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Línea Celular Tumoral , Proliferación Celular/genética , Resistencia a Antineoplásicos/genética , Regulación Neoplásica de la Expresión Génica , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Glioma/tratamiento farmacológico , Glioma/genética , Humanos , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Largo no Codificante/genética , Temozolomida/farmacología , Factores de Transcripción/genética
15.
Polymers (Basel) ; 14(7)2022 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-35406234

RESUMEN

As a new type of energetic material, reactive materials are widely used at present; in particular, the metal/polymer mixtures type reactive materials show great advantages in engineering applications. This type of reactive material has good mechanical properties, and its overall performance is insensitive and high-energy under external impact loading. After a large number of previous studies, our team found that the energy release characteristics of PTFE/Al/Si reactive material are prominent. In order to master the mechanical properties of PTFE/Al/Si reactive materials, the quasi-static mechanical properties and dynamic mechanical properties were obtained by carrying out a quasi-static compression test and a dynamic SHPB test in this paper. Based on the experimental data, a Johnson-Cook constitutive model of PTFE/Al/Si reactive material considering strain hardening effect, strain rate hardening effect and thermal softening effect was constructed. The relevant research results will be used to guide future research on the reaction mechanism of PTFE/Al/Si reactive materials, in order to promote the engineering application of PTFE/Al/Si reactive materials.

16.
Adv Mater ; 34(34): e2109521, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35165952

RESUMEN

Ultrathin 2D semiconductor devices are considered to have beyond-silicon potential but are severely troubled by the high Schottky barriers of the metal-semiconductor contacts, especially for p-type semiconductors. Due to the severe Fermi-level pinning effect and the lack of conventional semimetals with high work functions, their Schottky hole barriers are hardly removed. Here, an all-van-der-Waals barrier-free hole contact between p-type tellurene semiconductor and layered 1T'-WS2 semimetal is reported, which achieves a zero Schottky barrier height of 3 ± 9 meV and a high field-effect mobility of ≈1304 cm2 V-1 s-1 . The formation of such contacts can be attributed to the higher work function of ≈4.95 eV of the 1T'-WS2 semimetal, which is in sharp contrast with low work function (4.1-4.7 eV) of conventional semimetals. The study defines an available strategy for eliminating the Schottky barrier of metal-semiconductor contacts, facilitating 2D-semiconductor-based electronics and optoelectronics to extend Moore's law.

17.
Small Methods ; 6(4): e2101583, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35212464

RESUMEN

Facing the constant scaling down and thus increasingly severe self-heating effect, developing ultrathin and heat-insensitive ferroelectric devices is essential for future electronics. However, conventional ultrathin ferroelectrics and most 2D ferroelectric materials (2DFMs) are not suitable for high-temperature operation due to their low Curie temperature. Here, by using few-layer α-In2 Se3 , a special 2DFM with high Curie temperature, van der Waals (vdW) ferroelectric tunnel junction (FTJ) memories that deliver outstanding and reliable performance at both room and high temperatures are constructed. The vdW FTJs offer a large on/off ratio of 104 at room temperature and still reveal excellent on/off ratio at an ultrahigh temperature of 470 K, which will fail down other 2DFMs. Moreover, long retention and reliable cyclic endurance at high temperature are achieved, showing robust thermal stability of the vdW FTJ memory. The observations of this work demonstrate an exciting promise of α-In2 Se3 for reliable service in high temperature either from self-heating or harsh environments.

18.
Proc Natl Acad Sci U S A ; 118(44)2021 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-34716269

RESUMEN

Cells cooperate as groups to achieve structure and function at the tissue level, during which specific material characteristics emerge. Analogous to phase transitions in classical physics, transformations in the material characteristics of multicellular assemblies are essential for a variety of vital processes including morphogenesis, wound healing, and cancer. In this work, we develop configurational fingerprints of particulate and multicellular assemblies and extract volumetric and shear order parameters based on this fingerprint to quantify the system disorder. Theoretically, these two parameters form a complete and unique pair of signatures for the structural disorder of a multicellular system. The evolution of these two order parameters offers a robust and experimentally accessible way to map the phase transitions in expanding cell monolayers and during embryogenesis and invasion of epithelial spheroids.


Asunto(s)
Fenómenos Biofísicos/fisiología , Procesamiento de Imagen Asistido por Computador/métodos , Especificidad de Órganos/fisiología , Transición de Fase , Animales , Ciclo Celular , Movimiento Celular , Proliferación Celular , Células Epiteliales/citología , Humanos , Morfogénesis , Neoplasias , Esferoides Celulares/citología , Cicatrización de Heridas
19.
Adv Sci (Weinh) ; 8(21): e2101417, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34499424

RESUMEN

Direct charge trapping memory, a new concept memory without any dielectric, has begun to attract attention. However, such memory is still at the incipient stage, of which the charge-trapping capability depends on localized electronic states that originated from the limited surface functional groups. To further advance such memory, a material with rich hybrid states is highly desired. Here, a van der Waals heterostructure design is proposed utilizing the 2D graphdiyne (GDY) which possesses abundant hybrid states with different chemical groups. In order to form the desirable van der Waals coupling, the plasma etching method is used to rapidly achieve the ultrathin 2D GDY with smooth surface for the first time. With the plasma-treated 2D GDY as charge-trapping layer, a direct charge-trapping memory based on GDY/MoS2 is constructed. This bilayer memory is featured with large memory window (90 V) and high degree of modulation (on/off ratio around 8 × 107 ). Two operating mode can be achieved and data storage capability of 9 and 10 current levels can be obtained, respectively, in electronic and opto-electronic mode. This GDY/MoS2 memory introduces a novel application of GDY as rich states charge-trapping center and offers a new strategy of realizing high performance dielectric-free electronics, such as optical memories and artificial synaptic.

20.
Materials (Basel) ; 14(13)2021 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-34206650

RESUMEN

Recent studies have shown that the energy release capacity of Polytetrafluoroethylene (PTFE)/Al with Si, and CuO, respectively, is higher than that of PTFE/Al. PTFE/Al/Si/CuO reactive materials with four proportions of PTFE/Si were designed by the molding-sintering process to study the influence of different PTFE/Si mass ratios on energy release. A drop hammer was selected for igniting the specimens, and the high-speed camera and spectrometer systems were used to record the energy release process and the flame spectrum, respectively. The ignition height of the reactive material was obtained by fitting the relationship between the flame duration and the drop height. It was found that the ignition height of PTFE/Al/Si/CuO containing 20% PTFE/Si is 48.27 cm, which is the lowest compared to the ignition height of other Si/PTFE ratios of PTFE/Al/Si/CuO; the flame temperature was calculated from the flame spectrum. It was found that flame temperature changes little for the same reactive material at different drop heights. Compared with the flame temperature of PTFE/Al/Si/CuO with four mass ratios, it was found that the flame temperature of PTFE/Al/Si/CuO with 20% PTFE/Si is the highest, which is 2589 K. The results show that PTFE/Al/Si/CuO containing 20% PTFE/Si is easier to be ignited and has a stronger temperature destruction effect.

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