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1.
Neurosci Bull ; 40(3): 383-400, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37715924

RESUMEN

Neurological manifestations of coronavirus disease 2019 (COVID-19) are less noticeable than the respiratory symptoms, but they may be associated with disability and mortality in COVID-19. Even though Omicron caused less severe disease than Delta, the incidence of neurological manifestations is similar. More than 30% of patients experienced "brain fog", delirium, stroke, and cognitive impairment, and over half of these patients presented abnormal neuroimaging outcomes. In this review, we summarize current advances in the clinical findings of neurological manifestations in COVID-19 patients and compare them with those in patients with influenza infection. We also illustrate the structure and cellular invasion mechanisms of SARS-CoV-2 and describe the pathway for central SARS-CoV-2 invasion. In addition, we discuss direct damage and other pathological conditions caused by SARS-CoV-2, such as an aberrant interferon response, cytokine storm, lymphopenia, and hypercoagulation, to provide treatment ideas. This review may offer new insights into preventing or treating brain damage in COVID-19.


Asunto(s)
COVID-19 , Accidente Cerebrovascular , Humanos , COVID-19/complicaciones , COVID-19/metabolismo , SARS-CoV-2 , Accidente Cerebrovascular/metabolismo , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo
2.
Am J Physiol Endocrinol Metab ; 326(1): E1-E13, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37938178

RESUMEN

N6-methyladenosine (m6A) is the most prevalent post-transcriptional internal RNA modification, which is involved in the regulation of diverse physiological processes. Dynamic and reversible m6A modification has been shown to regulate glucose metabolism, and dysregulation of m6A modification contributes to glucose metabolic disorders in multiple organs and tissues including the pancreas, liver, adipose tissue, skeletal muscle, kidney, blood vessels, and so forth. In this review, the role and molecular mechanism of m6A modification in the regulation of glucose metabolism were summarized, the potential therapeutic strategies that improve glucose metabolism by targeting m6A modifiers were outlined, and feasible directions of future research in this field were discussed as well, providing clues for translational research on combating metabolic diseases based on m6A modification in the future.


Asunto(s)
Adenosina , Procesamiento Postranscripcional del ARN , Adenosina/genética , Adenosina/metabolismo , Homeostasis , Glucosa/metabolismo
3.
J Phys Condens Matter ; 36(4)2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37832557

RESUMEN

In this paper, an anisotropic magnetoresistive (AMR) thin film sensor which can be used for magnetic scale has been prepared, and its output voltage is about 4.7-4.9 mV V-1. On the basis of the Stoner-Wohlfarth model and with considering the non-uniformity of the demagnetizing field along the width direction of the strips, both the static and dynamic responses of the AMR sensors have been calculated. The results have shown that the calculated results are in agreement with the experimental data. The magnetization rotation in the magnetic sensor strongly depends on the nonuniform demagnetizing field along the width direction. The magnetization at the center is easily rotated into the field direction, and the magnetization at the edge is difficult to be rotated. The smaller the width of the magnetoresistive strip is, the larger both the demagnetizing field at the edge and the saturation field of the magnetic sensor are. The results are helpful for understanding the magnetization rotation of magnetic sensors and developing the magnetic sensors with high performance.

4.
Nat Commun ; 14(1): 5705, 2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37709777

RESUMEN

Nanosized metals usually exhibit ultrahigh strength but suffer from low homogeneous plasticity. The origin of a strength-ductility trade-off has been well studied for pure metals, but not for random solid solution (RSS) alloys. How RSS alloys accommodate plasticity and whether they can achieve synergy between high strength and superplasticity has remained unresolved. Here, we show that face-centered cubic (FCC) RSS AuCu alloy nanowires (NWs) exhibit superplasticity of ~260% and ultrahigh strength of ~6 GPa, overcoming the trade-off between strength and ductility. These excellent properties originate from profuse hexagonal close-packed (HCP) phase generation (2H and 4H phases), recurrence of reversible FCC-HCP phase transition, and zigzag-like nanotwin generation, which has rarely been reported before. Such a mechanism stems from the inherent chemical inhomogeneity, which leads to widely distributed and overlapping energy barriers for the concurrent activation of multiple plasticity mechanisms. This naturally implies a similar deformation behavior for other highly concentrated solid-solution alloys with multiple principal elements, such as high/medium-entropy alloys. Our findings shed light on the effect of chemical inhomogeneity on the plastic deformation mechanism of solid-solution alloys.

5.
Patterns (N Y) ; 4(9): 100841, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37720332

RESUMEN

[This corrects the article DOI: 10.1016/j.patter.2022.100609.].

6.
Environ Sci Pollut Res Int ; 30(36): 86365-86379, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37407859

RESUMEN

This study used deep learning to evaluate the ecological vulnerability of Chongqing, China, discuss the deep learning evaluations of ecological vulnerability, and generate vulnerability maps that support local ecological environment protection and governance decisions and provide reference for future studies. The information gain ratio was used to screen the influencing factors, selecting 16 factors that influence ecological vulnerability. Deep neural network (DNN) and convolutional neural network (CNN) methods were used for modeling, and two ecological vulnerability maps of the study area were generated. The results showed that the mean absolute error and root mean square error of the DNN and CNN models were relatively small, and the fitting accuracy was high. The area under the receiver operating characteristic curve of the CNN model was 0.926, which was better than that of the DNN model (0.888). Random forest was applied to calculate the importance of the influencing factors in the two models. Because the main factor was geological features, the relative ecological vulnerability was mainly affected by karst topography. Through the analysis of the ecological vulnerability map, the areas with higher vulnerability are the karst mountains of Dabashan, Wushan, and Qiyaoshan in the northeast and southeast, as well as the valley between mountains and cities in the center and west of the study area. According to the investigation of these areas, the primary ecological problems are low forest quality, structural irregularities caused by self-geological factors, severe desertification, and soil erosion. Human activity is also an important factor that causes ecological vulnerability in the study area. In conclusion, deep learning, particularly CNN models, can be used for ecological vulnerability assessments. The ecological vulnerability maps conformed to the basic cognition of field surveys and can provide references for other deep learning vulnerability studies. While the overall vulnerability of the study area is not high, ecological problems that lead to its vulnerability should be addressed by future ecological protection and management measures.


Asunto(s)
Aprendizaje Profundo , Humanos , Redes Neurales de la Computación , Ciudades , China , Bosques Aleatorios
7.
J Crit Care ; 78: 154342, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37302381

RESUMEN

PURPOSE: To analyze the effectiveness of sleep interventions in reducing the incidence and duration of delirium in the ICU. MATERIALS AND METHODS: We searched the PubMed, Embase, CINAHL, Web of Science, Scopus, and Cochrane databases for relevant randomized controlled trials from inception to August 2022. Literature screening, data extraction, and quality assessment were performed independently by two investigators. Data from the included studies were analyzed using Stata and TSA software. RESULTS: Fifteen randomized controlled trials were eligible. Meta-analysis showed that the sleep intervention was associated with a reduced incidence of delirium in the ICU (RR = 0.73, 95% CI = 0.58 to 0.93, p < 0.001) compared to the control group. The results of the trial sequence analysis further confirm that sleep interventions are effective in reducing the occurrence of delirium. Pooled data from the three dexmedetomidine trials showed significant differences in the incidence of ICU delirium between groups (RR = 0.43, 95% CI = 0.32 to 0.59, p < 0.001). The respective pooled results of other sleep interventions (e.g., light therapy, earplugs, melatonin, and multicomponent nonpharmacologic treatments) did not find a significant effect on reducing the incidence and duration of ICU delirium (p > 0.05). CONCLUSIONS: The current evidence suggests that non-pharmacological sleep interventions are not effective in preventing delirium in ICU patients. However, limited by the number and quality of included studies, future well-designed multicenter randomized controlled trials are still needed to validate the results of this study.


Asunto(s)
Delirio , Humanos , Delirio/epidemiología , Enfermedad Crítica/terapia , Sueño , Unidades de Cuidados Intensivos , Estudios Multicéntricos como Asunto
8.
Patterns (N Y) ; 3(11): 100609, 2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36419453

RESUMEN

Why are the transition temperatures (T c) of superconducting materials so different? The answer to this question is not only of great significance in revealing the mechanism of high-T c superconductivity but also can be used as a guide for the design of new superconductors. However, so far, it is still challenging to identify the governing factors affecting the T c. In this work, with the aid of machine learning and first-principles calculations, we found a close relevance between the upper limit of the T c and the energy-level distribution of valence electrons. It implies that some additional inter-orbital electron-electron interaction should be considered in the interpretation of high-T c superconductivity.

9.
Micromachines (Basel) ; 13(11)2022 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-36422398

RESUMEN

Oxide thin film thermocouples (TFTCs) are widely used in high-temperature environment measurements and have the advantages of good stability and high thermoelectric voltage. However, different annealing processes affect the performance of TFTCs. This paper studied the impact of different annealing times on the cyclic characteristics of ceramic oxide thin film thermocouples. ITO/In2O3 TFTCs were prepared on alumina ceramics by a screen printing method, and the samples were annealed at different times. The microstructure of the ITO film was studied by scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The results show that when the annealing temperature is fixed, the stability of the thermocouple is worst when it is annealed for 2 h. Extending the annealing time can improve the properties of the film, increase the density, slow down oxidation, and enhance the thermal stability of the thermocouple. The thermal cycle test results show that the sample can reach five temperature rise and fall cycles, more than 50 h, and can meet the needs of stable measurement in high temperature and harsh environments.

10.
Materials (Basel) ; 15(14)2022 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-35888538

RESUMEN

Tungsten-rhenium thin film thermocouples (TFTCs) are well suited for the surface temperature monitoring of hot components due to their small size, rapid response and low cost. In this study, a tungsten-rhenium TFTC with SiC protective film on all parts except the pads was fabricated by a microelectromechanical system (MEMS) process. During the low to medium temperature (-40 °C to 500 °C) repeatability test phase, the thermal voltage from the TFTC agreed well with that of the standard tungsten-rhenium thermocouple. However, during the high temperature test phase, the TFTC lost electronic response at around 620 °C. Failure analysis of the TFTC tested at 620 °C was performed by microscopy, scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), laser scanning confocal microscope (LSCM) and statistics. The results showed that the pads were oxidized without the protective layer, the number of oxidized protrusions distributed in this TFTC from the pad to the node decreases more and more slowly and the size of the oxidized protrusions also becomes smaller and smaller. This demonstrates the presence of horizontal oxidation diffusion in TFTCs, further illustrating the importance of pad protection and provides a direction for the subsequent structural optimization and the extension of the service life of TFTCs and other sensors.

11.
Molecules ; 27(13)2022 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-35807320

RESUMEN

Phytotherapy offers obvious advantages in the intervention of Coronary Artery Disease (CAD), but it is difficult to clarify the working mechanisms of the medicinal materials it uses. DGS is a natural vasoprotective combination that was screened out in our previous research, yet its potential components and mechanisms are unknown. Therefore, in this study, HPLC-MS and network pharmacology were employed to identify the active components and key signaling pathways of DGS. Transgenic zebrafish and HUVECs cell assays were used to evaluate the effectiveness of DGS. A total of 37 potentially active compounds were identified that interacted with 112 potential targets of CAD. Furthermore, PI3K-Akt, MAPK, relaxin, VEGF, and other signal pathways were determined to be the most promising DGS-mediated pathways. NO kit, ELISA, and Western blot results showed that DGS significantly promoted NO and VEGFA secretion via the upregulation of VEGFR2 expression and the phosphorylation of Akt, Erk1/2, and eNOS to cause angiogenesis and vasodilation. The result of dynamics molecular docking indicated that Salvianolic acid C may be a key active component of DGS in the treatment of CAD. In conclusion, this study has shed light on the network molecular mechanism of DGS for the intervention of CAD using a network pharmacology-driven strategy for the first time to aid in the intervention of CAD.


Asunto(s)
Enfermedad de la Arteria Coronaria , Medicamentos Herbarios Chinos , Animales , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Simulación del Acoplamiento Molecular , Farmacología en Red , Fosfatidilinositol 3-Quinasas/metabolismo , Fitoterapia , Proteínas Proto-Oncogénicas c-akt/metabolismo , Pez Cebra/metabolismo
12.
Science ; 375(6586): 1261-1265, 2022 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-35298254

RESUMEN

Grain boundaries (GBs) play an important role in the mechanical behavior of polycrystalline materials. Despite decades of investigation, the atomic-scale dynamic processes of GB deformation remain elusive, particularly for the GBs in polycrystals, which are commonly of the asymmetric and general type. We conducted an in situ atomic-resolution study to reveal how sliding-dominant deformation is accomplished at general tilt GBs in platinum bicrystals. We observed either direct atomic-scale sliding along the GB or sliding with atom transfer across the boundary plane. The latter sliding process was mediated by movements of disconnections that enabled the transport of GB atoms, leading to a previously unrecognized mode of coupled GB sliding and atomic plane transfer. These results enable an atomic-scale understanding of how general GBs slide in polycrystalline materials.

13.
World J Clin Cases ; 9(19): 5126-5134, 2021 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-34307563

RESUMEN

BACKGROUND: Patients undergoing lumbar spine surgery usually suffer severe pain in the postoperative period. The erector spinae plane block (ESPB), first published in 2016, can anesthetize the ventral and dorsal rami of thoracic nerves and produce an extensive multi-dermatomal sensory block. AIM: To assess whether bilateral ultrasound-guided ESPB at a lower thoracic level could improve pain control and quality of recovery in patients undergoing lumbar spine surgery. METHODS: A total of 60 patients aged 18-80 years scheduled to undergo lumbar spine surgery with general anesthesia were randomly assigned to two groups: ESPB group (preoperative bilateral ultrasound-guided ESPB at T10 vertebral level) and control group (no preoperative ESPB). Both groups received standard general anesthesia. The main indicator was the duration to the first patient controlled intravenous analgesia (PCIA) bolus. RESULTS: In the ESPB group, the duration to the first PCIA bolus was significantly longer than that in the control group (h) [8.0 (4.5, 17.0) vs 1.0 (0.5, 6), P < 0.01], and resting and coughing numerical rating scale (NRS) scores at 48 h post operation were significantly lower than those in the control group (P < 0.05). There was no significant difference between the two groups regarding resting and coughing NRS scores at 24 h post operation. Sufentanil consumption during the operation was significantly lower in the ESPB group than in the control group (P < 0.01), while there was no significant difference between the two groups regarding morphine consumption at 24 or 48 h post operation. In the ESPB group, Modified Observer's Assessment of Alertness/Sedation score within 20 min after extubation was higher and duration in the post-anesthesia care unit was shorter than those in the control group (P < 0.01). CONCLUSION: In patients undergoing lumbar spine surgery, ultrasound-guided ESPB at a lower thoracic level improves the analgesic effect, reduces opioid consumption, and improves postoperative recovery.

14.
J Orthop Surg Res ; 16(1): 196, 2021 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-33731160

RESUMEN

BACKGROUND: The best treatment for acute Achilles tendon ruptures remains controversial. No cohort studies have compared different immobilisation durations after open surgery. This retrospective cohort study aimed to determine the optimal duration of immobilisation after this surgery. METHODS: A total of 266 patients with acute Achilles tendon rupture were divided into 4 groups (A, B, C, and D) according to immobilisation duration of 0, 2, 4, and 6 weeks, respectively. All patients underwent the same suture technique with a similar rehabilitation protocol and were examined clinically at 2, 4, 6, 8, 10, 12, 14, 16, 24, and 48 weeks, with a final follow-up at a mean of 22.3 months postoperatively. The primary outcome was the time of return to light sports activity (LSA). Secondary outcomes included range of motion (ROM) and single-legged heel rise height (SHRH). Data on operation time, complications, visual analogue pain scale (VAS), American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score, and Achilles tendon Total Rupture score (ATRS) were also collected. Demographic baseline data were analysed using one-way analysis of variance; outcome parameters were analysed using Kruskal-Wallis H test, and complications were analysed using Fisher's exact test. Statistical significance was considered at P ≤ 0.05. RESULTS: VAS scores decreased significantly, reaching 0 in all groups after 12 weeks. The AOFAS and ATRS scores were significantly different between the groups from weeks 2 to 12 (P<0.001) and weeks 2 to 16 (P<0.001), respectively. All the mean scores showed better results in group B than in the other groups. In terms of recovery time of ROM, SHRH, and LSA, groups A and B were significantly faster than groups C and D (P<0.001). There were 13 (13/266, 4.9%) complications: 5 superficial infections, 3 deep venous thrombosis, and 5 trauma-related re-ruptures. On the last follow-up, all complications had recovered. There were no significant differences in complications between the groups. CONCLUSIONS: Immobilisation for 2 weeks after this open surgery is the best choice for early rehabilitation and weight-bearing while minimising pain and other complications.


Asunto(s)
Tendón Calcáneo/lesiones , Tendón Calcáneo/cirugía , Inmovilización/métodos , Procedimientos Ortopédicos/métodos , Rotura/cirugía , Traumatismos de los Tendones/cirugía , Tendón Calcáneo/fisiopatología , Adulto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Rango del Movimiento Articular , Recuperación de la Función , Estudios Retrospectivos , Rotura/fisiopatología , Rotura/rehabilitación , Traumatismos de los Tendones/fisiopatología , Traumatismos de los Tendones/rehabilitación , Factores de Tiempo , Resultado del Tratamiento , Soporte de Peso , Adulto Joven
15.
Clin Exp Rheumatol ; 39(1): 21-31, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32083545

RESUMEN

OBJECTIVES: Fibromyalgia (FM) is the most common chronic pain disease in middle-aged women. Patients may also complain of migraine, irritable bowel syndrome and depression, which seriously affect their work and life, causing huge economic losses to society. However, the pathogenesis of FM is still controversial and the effect of the current treatment is far from satisfactory. METHODS: Differentially expressed genes (DEGs) and miRNAs (DEMs) were found between FM and normal blood samples. The pathway and process enrichment analysis of the genes were performed. Protein-protein interaction network were constructed. Hub genes were found and analysed in The Comparative Toxicogenomics Database. RESULTS: A total of 102 genes were up-regulated and 46 down-regulated, 206 miRNAs down-regulated, and 15 up-regulated in FM. CD38, GATM, HDC, FOS were found as canditate genes. These genes were significantly associated with musculoskeletal disease, mental disorder, immune system disease. There was partial overlap between metformin therapy-related genes and FM-related genes. CONCLUSIONS: We found DEGs and DEMs in FM patients through bioinformatics analysis, which may be involved in the occurrence and development of FM and serve as potential targets for diagnosis and treatment.


Asunto(s)
Fibromialgia , MicroARNs , Anciano , Biología Computacional , Femenino , Fibromialgia/genética , Fibromialgia/terapia , Perfilación de la Expresión Génica , Redes Reguladoras de Genes , Humanos , MicroARNs/genética , Persona de Mediana Edad , Mapas de Interacción de Proteínas
16.
RSC Adv ; 11(23): 13964-13969, 2021 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-35423914

RESUMEN

Negative magnetoresistance (MR) is not only of great fundamental interest for condensed matter physics and materials science, but also important for practical applications, especially magnetic data storage and sensors. However, the microscopic origin of negative MR is still elusive and the nature of the negative MR in magnetic topological insulators has still not been completely elucidated. Here, we report magnetotransport studies on Cr doped (Bi1-x Sb x )2Te3 topological insulator thin films grown by magnetron sputtering. At the temperature of 2 K, a giant negative MR reaching 61% is observed at H = 2 T. We show that the negative MR is closely related to the position of the Fermi level, and it reaches the maximum when the Fermi level is gated near the charge neutral point. We attribute these results to the Coulomb potential due to the random composition fluctuations in Cr doped (Bi1-x Sb x )2Te3. Our results provide a deeper insight into the mechanism of negative MR, and are helpful to realize the quantum anomalous Hall effect in the sputtered Cr-(Bi1-x Sb x )2Te3 thin-film systems by tuning the Fermi level and reducing disorder effects.

17.
J Pain Res ; 13: 1611-1619, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32669870

RESUMEN

BACKGROUND: Erector spinae plane block (ESPB) as a new trunk fascia block technique was proposed in 2016. ESPB has aroused the interest of many nerve block experts. However, there are few clinical studies on ESPB for lumbar surgery, and its effectiveness and safety are controversial. The goal of this review is to summarize the use of ESPB for lumbar spine surgery in order to better understand this technique. METHODS: PubMed, EMBASE, Cochrane library and ClinicalTrial.gov databases were searched up to July 30, 2019. According to the inclusion and exclusion criteria established in advance, "lumbar spine surgery" and "ESPB" related MesH terms and free-text words were used. Data on pain scores, analgesic consumptions and adverse effects were reported. All processes follow PRISMA statement guidelines. RESULTS: A total of 171 participants from 11 publications were identified, including two randomized controlled trials (RCTs), one retrospective cohort study, four case reports and four cases series. Block operation planes from T8 to L4. The main anesthetics used in the block are bupivacaine, ropivacaine and lidocaine. There was evidence for reducing postoperative pain scores and analgesic consumptions. CONCLUSION: The effectiveness and safety of ESPB for lumbar spine surgery are still controversial. The current evidence is insufficient to support the widespread use of ESPB for lumbar spine surgery. High-quality RCTs are urgently needed.

18.
J Pain Res ; 13: 709-717, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32308470

RESUMEN

PURPOSE: Erector spinae plane block (ESPB) is a newly reported interfascial plane block in pain management, and it can block the nerves exactly in line with the area of the posterior lumbar surgery. The objective of this research was to determine the effectiveness of pre-operative ESPB in enhancing recovery of posterior lumbar surgery. PATIENTS AND METHODS: A total of 60 patients undergoing open posterior lumbar decompression surgery under general anesthesia were randomized into two groups. T12 group was performed pre-operatively bilateral ESPB with ropivacaine at the T12 level, but control group did not receive the block. The primary outcome was the Modified Observer's Assessment of Alertness/Sedation (MOAA/S) score at 10 minutes after extubation. Secondary outcomes included intraoperative sufentanil consumption, postoperative morphine consumption, first time to ambulation after surgery and hospital length of stay after surgery. All participants were followed up to hospital discharge. RESULTS: The mean (SD) MOAA/S scores at 10 minutes after extubation were 4.2 (95% CI, 4.0 to 4.4), and 3.4 (95% CI, 3.2 to 3.6) in the T12 and control groups (P <0.001), respectively. Intraoperative sufentanil consumption (P =0.007) and postoperative morphine consumption (P =0.003) were lower in the T12 group than in the control group. Although first time to ambulation after surgery was sooner in the T12 group than in the control group (P =0.003), hospital length of stay was similar (P=0.054). CONCLUSION: Pre-operative bilateral ESPB at T12 can enhance recovery after posterior lumbar surgery and reduce perioperative opioid consumption.

19.
Nat Commun ; 11(1): 1167, 2020 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-32127536

RESUMEN

Twin-thickness-controlled plastic deformation mechanisms are well understood for submicron-sized twin-structural polycrystalline metals. However, for twin-structural nanocrystalline metals where both the grain size and twin thickness reach the nanometre scale, how these metals accommodate plastic deformation remains unclear. Here, we report an integrated grain size and twin thickness effect on the deformation mode of twin-structural nanocrystalline platinum. Above a ∼10 nm grain size, there is a critical value of twin thickness at which the full dislocation intersecting with the twin plane switches to a deformation mode that results in a partial dislocation parallel to the twin planes. This critical twin thickness value varies from ∼6 to 10 nm and is grain size-dependent. For grain sizes between ∼10 to 6 nm, only partial dislocation parallel to twin planes is observed. When the grain size falls below 6 nm, the plasticity switches to grain boundary-mediated plasticity, in contrast with previous studies, suggesting that the plasticity in twin-structural nanocrystalline metals is governed by partial dislocation activities.

20.
Chin J Integr Med ; 25(9): 648-653, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31650485

RESUMEN

As an interdisciplinary subject of medicine and artificial intelligence, intelligent diagnosis and treatment has received extensive attention. The standardization of Chinese medicine (CM) diagnosis has been always a bottleneck in the modernization and globalization of CM. Studying the application technology of artificial intelligence in CM and solving the problems is an urgent need for the development of modern CM in the era of artificial intelligence. Taking the pneumonia with dyspnea and cough in CM as an example, this article gives an overview of intelligent medical technology and application development, brings forward the present technical problems faced and the new advances in intelligent technology on CM diagnosis and treatment.


Asunto(s)
Inteligencia Artificial , Medicina Tradicional de Asia Oriental , Aprendizaje Profundo , Enfermedad , Humanos , Síndrome
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