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1.
Sci Rep ; 13(1): 13438, 2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37596299

RESUMEN

Utilizing micromagnetic modeling, we have explained the unprobed characteristics of 360° full cycle in-plane magnetization rotation and the resulting propagation of a magnetization wave along a ferromagnet nanowire. The magnetization wave, which is generated by setting off spin oscillation at one end of a ferromagnetic strip, propagates till the end of the wire. A perpendicular spin torque oscillator (STO) could generate magnetization rotation at one end of the ferromagnetic strip that is also part of the STO. Our results demonstrate that the oscillation frequency of the spins along the wire maintains excellent fidelity while the spatial wavelength of the magnetic wave increases. The driving mechanism behind the propagation of the wave is found to be exchange-springs, which enables the propagation of the wave without the need for a 'carrier' force, such as spin-transfer torque (STT) or spin Hall effect (SHE). Furthermore, we demonstrate that the gradient of the exchange energy drives the magnetic wave forward, while the in and out of plane anisotropy fields govern the shape of spin oscillation trajectories along the wire. Additionally, we show that stopping the oscillation at the STO end causes the wave to cease propagation after relaxation, and altering the STO rotational chirality leads to merging and annihilating domain walls of opposite winding numbers.

2.
Sci Rep ; 13(1): 11087, 2023 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-37422591

RESUMEN

In this paper, we present an experimental study of L10-FePt granular films with crystalline boron nitride (BN) grain boundary materials for heat assisted magnetic recording (HAMR). It is found that application of a RF substrate bias (VDC = -15 V) yields the formation of hexagonal boron nitride (h-BN) nanosheets in grain boundaries, facilitating the columnar growth of FePt grains during sputtering at high temperatures. The h-BN monolayers conform to the side surfaces of columnar FePt grains, completely encircling individual FePt grains. The resulting core-shell FePt-(h-BN) nanostructures appear to be highly promising for HAMR application. The high thermal stability of h-BN grain boundaries allows the deposition temperature to be as high as 650℃ such that high order parameters of FePt L10 phase have been obtained. For the fabricated FePt-(h-BN) thin film, excellent granular microstructure with FePt grains of 6.5 nm in diameter and 11.5 nm in height has been achieved along with good magnetic hysteresis properties.


Asunto(s)
Grano Comestible , Películas Cinematográficas , Animales , Sesgo , Estro
3.
Rev Sci Instrum ; 94(7)2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37428024

RESUMEN

Trans-impedance amplifier (TIA) based capacitance-voltage (C-V) readout circuit is an attractive choice for micro-machined gyroscope for its simplicity and superior performance. In this work, the noise and the C-V gain characteristics of the TIA circuit are analyzed in detail. Then, a TIA based readout circuit with a C-V gain of about 286 dB is designed, and a series of experiments are conducted to test the performance of the circuit. Both the analysis and test results show that T-network TIA should be avoided as far as possible for its poor noise performance. All results also show that there is a signal-to-noise ratio (SNR) limit for the TIA based readout circuit, and the SNR can only be further improved by filtering. Hence, an adaptive finite impulse response filter is designed to further improve the SNR of the sensed signal. For a gyroscope with a peak-to-peak variable capacitance of about 200 aF, a SNR of 22.8 dB can be achieved by the designed circuit and a SNR of 47 dB can be obtained by further adaptive filtering. Finally, the solution presented in this paper achieves a capacitive sensing resolution of 0.9 aF.

4.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 35(4): 393-397, 2023 Apr.
Artículo en Chino | MEDLINE | ID: mdl-37308195

RESUMEN

OBJECTIVE: To evaluate the effect of curcumin on renal mitochondrial oxidative stress, nuclear factor-κB/NOD-like receptor protein 3 (NF-κB/NLRP3) inflammatory body signaling pathway and tissue cell injury in rats with acute respiratory distress syndrome (ARDS). METHODS: A total of 24 specific pathogen free (SPF)-grade healthy male Sprague-Dawley (SD) rats were randomly divided into control group, ARDS model group, and low-dose and high-dose curcumin groups, with 6 rats in each group. The ARDS rat model was reproduced by intratracheal administration of lipopolysaccharide (LPS) at 4 mg/kg via aerosol inhalation. The control group was given 2 mL/kg of normal saline. The low-dose and high-dose curcumin groups were administered 100 mg/kg or 200 mg/kg curcumin by gavage 24 hours after model reproduction, once a day. The control group and ARDS model group were given an equivalent amount of normal saline. After 7 days, blood samples were collected from the inferior vena cava, and the levels of neutrophil gelatinase-associated lipocalin (NGAL) in serum were determined by enzyme-linked immunosorbent assay (ELISA). The rats were sacrificed, and kidney tissues were collected. Reactive oxygen species (ROS) levels were determined by ELISA, superoxide dismutase (SOD) activity was detected using the xanthine oxidase method, and malondialdehyde (MDA) levels were determined by colorimetric method. The protein expressions of hypoxia-inducible factor-1α (HIF-1α), caspase-3, NF-κB p65, and Toll-like receptor 4 (TLR4) were detected by Western blotting. The mRNA expressions of HIF-1α, NLRP3, and interleukin-1ß (IL-1ß) were detected by reverse transcription-polymerase chain reaction (RT-PCR). Renal cell apoptosis was detected by TdT-mediated dUTP nick end labeling (TUNEL). The morphological changes in renal tubular epithelial cells and mitochondria were observed under a transmission electron microscope. RESULTS: Compared with the control group, the ARDS model group exhibited kidney oxidative stress and inflammatory response, significantly elevated serum levels of kidney injury biomarker NGAL, activated NF-κB/NLRP3 inflammasome signaling pathway, increased kidney tissue cell apoptosis rate, and renal tubular epithelial cell damage and mitochondrial integrity destruction under transmission electron microscopy, indicating successful induction of kidney injury. Following curcumin intervention, the injury to renal tubular epithelial cells and mitochondria in the rats was significantly mitigated, along with a noticeable reduction in oxidative stress, inhibition of the NF-κB/NLRP3 inflammasome signaling pathway, and a significant decrease in kidney tissue cell apoptosis rate, demonstrating a certain dose-dependency. Compared with the ARDS model group, the high-dose curcumin group exhibited significantly reduced serum NGAL levels and kidney tissue MDA and ROS levels [NGAL (µg/L): 13.8±1.7 vs. 29.6±2.7, MDA (nmol/g): 115±18 vs. 300±47, ROS (kU/L): 75±19 vs. 260±15, all P < 0.05], significantly down-regulated protein expressions of HIF-1α, caspase-3, NF-κB p65, and TLR4 in the kidney tissue [HIF-1α protein (HIF-1α/ß-actin): 0.515±0.064 vs. 0.888±0.055, caspase-3 protein (caspase-3/ß-actin): 0.549±0.105 vs. 0.958±0.054, NF-κB p65 protein (NF-κB p65/ß-actin): 0.428±0.166 vs. 0.900±0.059, TLR4 protein (TLR4/ß-actin): 0.683±0.048 vs. 1.093±0.097, all P < 0.05], and significantly down-regulated mRNA expressions of HIF-1α, NLRP3, and IL-1ß [HIF-1α mRNA (2-ΔΔCt): 2.90±0.39 vs. 9.49±1.87, NLRP3 mRNA (2-ΔΔCt): 2.07±0.21 vs. 6.13±1.32, IL-1ß mRNA (2-ΔΔCt): 1.43±0.24 vs. 3.95±0.51, all P < 0.05], and significantly decreased kidney tissue cell apoptosis rate [(4.36±0.92)% vs. (27.75±8.31)%, P < 0.05], and significantly increased SOD activity (kU/g: 648±34 vs. 430±47, P < 0.05). CONCLUSIONS: Curcumin can alleviate kidney injury in ARDS rats, and its mechanism may be related to the increasing in SOD activity, reduction of oxidative stress, and inhibition of the activation of the NF-κB/NLRP3 inflammasome signaling pathway.


Asunto(s)
Curcumina , FN-kappa B , Masculino , Ratas , Animales , Ratas Sprague-Dawley , Actinas , Caspasa 3 , Lipocalina 2 , Receptor Toll-Like 4 , Inflamasomas , Proteína con Dominio Pirina 3 de la Familia NLR , Especies Reactivas de Oxígeno , Solución Salina , Riñón , Superóxido Dismutasa
5.
Ecol Evol ; 13(5): e10055, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37181202

RESUMEN

Assessing plant diversity during community succession based on plant trait and phylogenetic features within a community (alpha scale) and among communities (beta scale) could improve our understanding of community succession mechanism. However, whether changes of community functional diversity at alpha and beta scale are structured by different traits and whether integrating plant traits and phylogeny can enhance the ability in detecting diversity pattern have not been studied in detail. Thirty plots representing different successional stages were established on the Loess Plateau of China and 15 functional traits were measured for all coexisting species. We first analyzed the functional alpha and beta diversity along succession by decomposing species trait into alpha and beta components and then integrated key traits with phylogenetic information to explore their roles in shaping species turnover during community succession. We found that functional alpha diversity increased along successional stages and was structured by morphological traits, while beta diversity decreased during succession and was more structured by stoichiometry traits. Phylogenetic alpha diversity showed congruent pattern with functional alpha diversity because of phylogenetic conservation of trait alpha components (variation within community), while beta diversity showed incongruent pattern due to phylogenetic randomness of trait beta components (variation among communities). Furthermore, only integrating relatively conserved traits (plant height and seed mass) and phylogenetic information can raise the detecting ability in assessing diversity change. Overall, our results reveal the increasing niche differentiation within community and functional convergence among communities with succession process, indicating the importance of matching traits with scale in studying community functional diversity and the asymmetry of traits and phylogeny in reflecting species ecological differences under long-term selection pressures.

6.
Mol Biotechnol ; 65(6): 983-996, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36427097

RESUMEN

Hemorrhagic shock is a frequent threat to pregnant women, and blood transfusions can contribute to organ damage, including hepatic ischemia-reperfusion (HIR) injury. LncRNA SNHG7 (SNHG7) has been reported to exert an essential role in various diseases, while the effect of SNHG7 on HIR injury induced by hemorrhagic shock and reperfusion in pregnant rats is still unclear. In our study, we examined the function and mechanism of SNHG7 in the progression of HIR injury in pregnant rats. The results showed that SNHG7 expression was low in the hepatic tissues of pregnant rats after the hemorrhagic shock and reperfusion modeling. Knockdown of SNHG7 further aggravated hepatic injury, apoptosis, and oxidative stress induced by hemorrhagic shock and reperfusion during pregnancy. Additionally, SNHG7 was bound directly to miR-34a-5p, and miR-34a-5p inhibitors partially reversed the effect of SNHG7 silencing on models of hemorrhagic shock and reperfusion. Furthermore, YWHAG is a direct target of miR-34a-5p and is negatively regulated by miR-34a-5p mimics. Overexpression of YWHAG effectively eliminated the effect of SNHG7 knockdown on pregnant rats. In summary, this investigation proved that SNHG7 knockdown exacerbated HIR injury after hemorrhagic shock in pregnant rats, and reperfusion might by mediating miR-34a-5p/YWHAG axis, indicating that SNHG7 can serve as a target gene for the treatment of HIR injury caused by hemorrhagic shock and reperfusion during pregnancy.


Asunto(s)
MicroARNs , ARN Largo no Codificante , Daño por Reperfusión , Choque Hemorrágico , Ratas , Humanos , Femenino , Animales , Embarazo , MicroARNs/genética , MicroARNs/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Choque Hemorrágico/genética , Daño por Reperfusión/genética , Apoptosis/genética , Proteínas 14-3-3/metabolismo
7.
World J Clin Cases ; 10(32): 11861-11868, 2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36405297

RESUMEN

BACKGROUND: Cardiac arrest after noncardiac surgery is a dangerous complication that may contribute to mortality. Because of the high mortality rate and many complications of cardiac arrest, it is very important to identify and correct a reversible etiology early. By reporting the treatment process of this case, we aimed to broaden the diagnosis and treatment of cardiac arrest after noncardiac surgery and describe how cardiopulmonary resuscitation using extracorporeal membrane oxygenation (ECMO) can improve a patient's chance of survival. CASE SUMMARY: A 69-year-old man visited our hospital complaining of low back pain on July 12, 2021. Magnetic resonance imaging showed lumbar disc herniation. Two hours after lumbar disc herniation surgery, the patient developed cardiac arrest. Cardiopulmonary resuscitation was performed, and ECMO was started 60 min after the initiation of cardiopulmonary resuscitation. Regarding the etiology of early cardiac arrest after surgery, acute myocardial infarction and pulmonary embolism were considered first. Based on ultrasound evaluation, acute myocardial infarction appeared more likely. Coronary angiography confirmed occlusion of the left anterior descending branch, and coronary artery stenting was performed. Pulmonary artery angiography was performed to exclude pulmonary embolism. Due to heparinization during ECMO and coronary angiography, there was a large amount of oozing blood in the surgical incision. Therefore, heparin-free ECMO was performed in the early stage, and routine heparinized ECMO was performed after hemorrhage stabilization. Eventually, the patient was discharged and made a full neurologic recovery. CONCLUSION: For early postoperative cardiac arrest, acute myocardial infarction should be considered first, and heparin should be used with caution.

8.
Opt Express ; 30(11): 18949-18965, 2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-36221684

RESUMEN

We present a tunable on-chip liquid resonator in conjunction with a tapered fiber coupling scheme. The resonator consists of a glycerol droplet submerged within an immiscible liquid bath, which mitigates the effects of environmental fluctuations. The platform is fabricated using standard semiconductor techniques, which enable the future integration of photonic components for an on-chip liquid resonator device. The liquid resonator maintains its high Q-factor on chip (105) due to surface tension forming an atomically smooth liquid-liquid interface. Higher Q-factor resonance modes experienced linewidth broadening due to the random excitation of thermal capillary vibrations. Spectral tuning is demonstrated using the electrowetting effect, increasing the surface's wettability and an expansion in the droplet diameter. A maximum spectral tuning of 1.44 nm ± 5 pm is observed by applying 35 V. The tuning range is twice the free spectral range (FSR) of 0.679 nm measured at a pumping wavelength range of 770-775 nm. A 2D axisymmetric finite-element simulation shows resonance modes in good agreement with experimentally measured spectra and with predicted tuning speeds of 20 nm/s.

9.
Front Public Health ; 10: 926069, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35812523

RESUMEN

In December 2019, an outbreak of novel coronavirus pneumonia spread over Wuhan, Hubei Province, China, which then developed into a significant global health public event, giving rise to substantial economic losses. We downloaded throat swab expression profiling data of COVID-19 positive and negative patients from the Gene Expression Omnibus (GEO) database to mine novel diagnostic biomarkers. XGBoost was used to construct the model and select feature genes. Subsequently, we constructed COVID-19 classifiers such as MARS, KNN, SVM, MIL, and RF using machine learning methods. We selected the KNN classifier with the optimal MCC value from these classifiers using the IFS method to identify 24 feature genes. Finally, we used principal component analysis to classify the samples and found that the 24 feature genes could effectively be used to classify COVID-19-positive and negative patients. Additionally, we analyzed the possible biological functions and signaling pathways in which the 24 feature genes were involved by GO and KEGG enrichment analyses. The results demonstrated that these feature genes were primarily enriched in biological functions such as viral transcription and viral gene expression and pathways such as Coronavirus disease-COVID-19. In summary, the 24 feature genes we identified were highly effective in classifying COVID-19 positive and negative patients, which could serve as novel markers for COVID-19.


Asunto(s)
COVID-19 , Neumonía , Biomarcadores , COVID-19/diagnóstico , Humanos , Aprendizaje Automático , SARS-CoV-2/genética
10.
Front Chem ; 9: 747385, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34746092

RESUMEN

This paper briefly discussed the research progress of biomass-based transparent wood (BBTW), and summarized the key technologies and potential application prospects of BBTW in replacing architectural glass. Based on the introduction of the preparation process of BBTW, the advantages of BBTW and their feasibility to replace architectural glass are illustrated with a view to the requirements and conditions of architectural glass for different use functions. The limitations of BBTW are discussed and the development prospects of BBTW are also prospected. The research shows that BBTW has the advantages of green and renewable materials that can meet the requirements of good lighting conditions, flame retardant, heat insulation and safety, which are in line with the sustainable development trend. Further studies are needed to continuously break through its limitations with an aim to expand the application of this new biomass-based material.

11.
Front Plant Sci ; 12: 698878, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35126402

RESUMEN

The trait-based approaches have made progress in understanding the community assembly process. Here, we explore the key traits that may shape community assembly patterns of the same community type but within different water availabilities. Natural Quercus wutaishanica forests were chosen as a suitable study system to test the difference between economic and hydraulic traits across water availability on the Loess Plateau (LP, drought region) and Qinling Mountains (QL, humid region) of China. A total of 75 plots were established separately in two sites, and 12 functional traits (seven hydraulic traits and five economic traits) of 167 species were studied. Community-weighted mean trait values and functional diversity indices were compared between the two sites. Canonical component analysis was performed to infer whether the changes of community traits and their relationships are driven by intraspecific variation or species turnover. Evidence for likely community assembly processes was tested using the null model to determine whether functional structure among seven hydraulic traits and five economic traits was dominated by different ecological processes between two sites. We found that forests in the Loess Plateau and Qinling Mountains showed different hydraulic and economic traits. Hydraulic and economic traits coupled at the community level were driven by species turnover. Hydraulic traits showed more significant convergent patterns on LP than that in QL. Our results suggest a strong environmental filtering process occurred in hydraulic-based community assembly in the temperate forest with low water availability. Reveal the relationship of hydraulic and economic traits at the community level. Emphasize the critical role of multi-dimensional traits selecting like hydraulic traits in community ecology.

12.
Transl Cancer Res ; 9(3): 1806-1817, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35117528

RESUMEN

BACKGROUND: Pancreatic cancer is an extensively concerned human malignancy around the globe, yet the potential therapeutic target remains to be further determined. MicroRNA and LncRNA have been reported to be involved in progression of pancreatic cancer, while the biological role of microRNA-574-3p (miR-574-3p) and FAM66C in pancreatic cancer development is poorly investigated. METHODS: Quantitative real-time PCR (qPCR) analysis was employed to detect the expression of miR-574-3p and FAM66C in pancreatic normal or cancerous tissues and cells. The proliferative and apoptosis signaling molecules were also examined via qPCR and western blot separately. Additionally, cell proliferation and apoptosis assay were performed via CCK8, colony formation and Annexin V-FITC apoptosis assay. Interaction between miR-574-3p and FAM66C was interrogated by luciferase reporter assay and RNA immunoprecipitation. Even more, a pancreatic cancer xenograft mice assay was implemented to illustrate the coordinating role of miR-574-3p and FAM66C in pancreatic cancer proliferation. RESULTS: We found that levels of miR-574-3p were significantly higher in cancer tissues and cells compared to normal (P<0.05). Remarkably, the results indicated that depletion of miR-574-3p inhibited proliferation and promoted apoptosis of human pancreatic cancer cell lines. Additionally, FAM66C was demonstrated to interact with miR-574-3p and inhibit its expression. Significantly, FAM66C was proved to act as a tumor suppressor role via inhibiting cell proliferation and promoting cell apoptosis in pancreatic cancer. Moreover, FAM66C coordinated with miR-574-3p to regulate progression of xenograft tumor in the nude mice. CONCLUSIONS: FAM66C-miR-574-3p axis mediates progression of pancreatic and might be the promising therapeutic target for pancreatic cancer patients.

13.
Opt Express ; 27(23): 33606-33620, 2019 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-31878425

RESUMEN

Chalcogenides are a promising platform for infrared nonlinear optics but are susceptible to structural changes during fabrication that affect their linear and nonlinear optical properties. We analyze the structure and optical properties of thermally evaporated and annealed chalcogenide films. Thermally evaporated Ge28Sb12Se60 has an increased selenium content, bandgap, and concentration of heteropolar bonds. The concentration of heteropolar bonds can be reduced by annealing above the glass transition temperature, resulting in improved optical nonlinearity. We demonstrate a 4-fold enhancement of third-order nonlinearity in Ge28Sb12Se60 chalcogenide waveguides by thermal annealing and a decrease in propagation loss from 2.5 dB/cm to 1 dB/cm as an added benefit.

14.
Sci Rep ; 9(1): 325, 2019 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-30674984

RESUMEN

Magnetization switching by spin-orbit torque (SOT) via spin Hall effect represents as a competitive alternative to that by spin-transfer torque (STT) used for magnetoresistive random access memory (MRAM), as it doesn't require high-density current to go through the tunnel junction. For perpendicular MRAM, however, SOT driven switching of the free layer requires an external in-plane field, which poses limitation for viability in practical applications. Here we demonstrate field-free magnetization switching of a perpendicular magnet by utilizing an Iridium (Ir) layer. The Ir layer not only provides SOTs via spin Hall effect, but also induce interlayer exchange coupling with an in-plane magnetic layer that eliminates the need for the external field. Such dual functions of the Ir layer allows future build-up of magnetoresistive stacks for memory and logic applications. Experimental observations show that the SOT driven field-free magnetization reversal is characterized as domain nucleation and expansion. Micromagnetic modeling is carried out to provide in-depth understanding of the perpendicular magnetization reversal process in the presence of an in-plane exchange coupling field.

15.
Phys Rev Lett ; 121(20): 207202, 2018 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-30500236

RESUMEN

Collinear antiferromagnets (AFs) support two degenerate magnon excitations carrying opposite spin polarizations, by which magnons can function as electrons in various spin-related phenomena. In an insulating ferromagnet(F)/AF/F trilayer, we explore the magnon-mediated interlayer coupling by calculating the magnon thermal energy in the AF as a function of the orientations of the Fs. The effect manifests as an interlayer exchange interaction and a perpendicular magnetic anisotropy; they both depend on temperature and the AF thickness. In particular, the exchange interaction turns out to be antiferromagnetic at low temperatures and ferromagnetic at high temperatures, whose magnitude can be 10-100 µeV for nanoscale separations, allowing experimental verification.

16.
Sci Rep ; 7(1): 8896, 2017 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-28827679

RESUMEN

We demonstrate a magnetometer using polymer encapsulated whispering-gallery-mode microcavity actuated by a micro-magnet. The magnetic field induces force on the micro-magnet causing deformation in the polymer around the microcavity. Subsequently the microcavity detects the change in the refractive index of the polymer resulted from the deformation. This magnetometer works in the frequency range of hertz-to-kilohertz range and achieves a sensitivity of 880 pT/Hz1/2 at 200 Hz in a micro-scale sensor volume. Polymer encapsulation of the magnetometer and fiber optical connection ensures environmental robustness and practicality of the sensor.

17.
Phys Rev Lett ; 117(9): 097202, 2016 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-27610880

RESUMEN

In ferromagnet-normal-metal heterostructures, spin pumping and spin-transfer torques are two reciprocal processes that occur concomitantly. Their interplay introduces a dynamic feedback effect interconnecting energy dissipation channels of both magnetization and current. By solving the spin diffusion process in the presence of the spin Hall effect in the normal metal, we show that the dynamic feedback gives rise to (i) a nonlinear magnetic damping that is crucial to sustain uniform steady-state oscillations of a spin Hall oscillator at large angles and (ii) a frequency-dependent spin Hall magnetoimpedance that reduces to the spin Hall magnetoresistance in the dc limit.

18.
Sci Rep ; 6: 24223, 2016 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-27048928

RESUMEN

In a collinear antiferromagnet with easy-axis anisotropy, symmetry dictates that the spin wave modes must be doubly degenerate. Theses two modes, distinguished by their opposite polarization and available only in antiferromagnets, give rise to a novel degree of freedom to encode and process information. We show that the spin wave polarization can be manipulated by an electric field induced Dzyaloshinskii-Moriya interaction and magnetic anisotropy. We propose a prototype spin wave field-effect transistor which realizes a gate-tunable magnonic analog of the Faraday effect, and demonstrate its application in THz signal modulation. Our findings open up the exciting possibility of digital data processing utilizing antiferromagnetic spin waves and enable the direct projection of optical computing concepts onto the mesoscopic scale.

19.
Exp Ther Med ; 10(3): 1074-1078, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26622442

RESUMEN

The aim of the present study was to evaluate the efficacy of helium-neon laser therapy in the treatment of hydroxyapatite orbital implant exposure and compare the results with those of a combined drugs and surgery regimen. A total of 70 patients with hydroxyapatite orbital implant exposure in 70 eyes were randomly divided into two groups: Helium-neon laser therapy (group A) and drugs plus surgery (group B). Each group contained 35 patients. The healing rates and times of the conjunctival wound were recorded and compared following helium-neon laser treatment or the drugs plus surgery regimen. Changes in the hydroxyapatite orbital implant prior to and following helium-neon laser irradiation were analyzed. A similar animal study was conducted using 24 New Zealand white rabbits, which received orbital implants and were then received drug treatment or helium-neon therapy. In the human experiment, the rates for conjunctival wound healing were 97.14% in group A and 74.29% in group B, with a significant difference between the groups (χ2=5.71, P<0.05). Patients with mild exposure were healed after 7.22±2.11 days of helium-neon laser therapy and 14.33±3.20 days of drugs plus surgery. A statistically significant difference was found between the groups (t=8.97, P<0.05). Patients with moderate to severe exposure were healed after 18.19±2.12 days of helium-neon laser therapy and 31.25±4.21 days of drugs plus surgery. The difference between the groups was statistically significant (t=7.91, P<0.05). Enhanced magnetic resonance imaging showed that the helium-neon laser therapy significantly promoted vascularization of the hydroxyapatite orbital implant. These results, combined with pathological findings in animals, which showed that a helium-neon laser promoted vascularization and had anti-inflammatory effects, suggest that helium-neon laser irradiation is an effective method for treating hydroxyapatite orbital implant exposure, thereby avoiding secondary surgery.

20.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 27(5): 349-53, 2015 May.
Artículo en Chino | MEDLINE | ID: mdl-26003638

RESUMEN

OBJECTIVE: To analyze the characteristics of severe trauma patients with acute kidney injury (AKI) receiving renal replacement therapy (RRT), in order to look for the risk factors of AKI and the opportune time for the initiation of RRT on prognosis. METHODS: A retrospective cohort study involving consecutive patients with severe trauma in emergency intensive care unit (ICU) in the Second Affiliated Hospital of Zhejiang University School of Medicine, from August 2011 to December 2014, was conducted. Inclusion criteria included age≥18 years, injury severity score (ISS) > 16, AKI receiving RRT, and the duration of hospital stay > 24 hours. The general data, the risk factors of AKI, the prognostic indicators, and the information of RRT were recorded. All patients were divided into two groups according to the prognosis, the time of onset of AKI and the initiation time of RRT. The independent risk factors for prognosis were screened by binary logistic regression analysis. RESULTS: Seventy-three patients were eligible for enrollment, including 48 deaths ( 65.8% ); 49 patients suffered from AKI≤48 hours after trauma (early stage group), and in 24 patients it was longer than 48 hours (late stage group). In 55 patients RRT was routinely started (routine RRT group), 18 patients underwent RRT ahead of routine criteria decided by the judgment of the attending doctor ( earlier RRT group). The main risk factors of RRT in traumatic patients with AKI were shock and sepsis, each accounted for 90.4% and 53.4%. Compared with survival group, in death group, the proportion of male patients was lower (70.8% vs. 100.0%, χ² = 7.238, P = 0.007), acute physiology and chronic health evaluation II ( APACHEII) scores were higher (23.7±5.1 vs. 14.4±3.7, t = 8.031, P < 0.001), Glasgow coma score (GCS) was lower [5.0 (3.0, 15.0) vs. 15.0 (8.0, 15.0 ), U = 320.000, P = 0.001 ], incidence of shock and sepsis was higher (97.9% vs. 76.0%, χ² = 6.755, P = 0.009; 64.6% vs. 32.0%, χ² = 7.014, P = 0.008), the rate of use of contrast medium was lower (27.1% vs. 56.0%, χ² = 5.898, P = 0.015), the time for the diagnosis of AKI post trauma was delayed [ days: 2 (1, 5) vs. 2 (1, 2), U = 762.000, P = 0.049 ], the time for the initiation of RRT post trauma was later [ days: 6.0 (3.0, 12.0) vs. 3.0 (2.0, 4.5), U = 868.500, P = 0.002 ], the recovery rate of renal function at discharge was lower (10.4% vs. 100.0%, χ² = 54.497, P < 0.001). Compared with late stage group, in early stage group, the mortality was lower (55.1% vs. 87.5%, χ² = 7.509, P = 0.006 ), and the incidence of sepsis before AKI was also lower (38.8% vs. 83.3%, χ² = 12.854, P < 0.001). Compared with routine RRT group, the recovery of renal function at discharge was better with a lower mortality rate in the earlier RRT group, but the difference was considered to be insignificant ( 55.6% vs. 36.4%, χ² = 2.064, P = 0.151; 50.0% vs. 70.9%, χ² = 2.633, P = 0.105). Logistic regression analysis showed GCS [odds ratio (OR) = 0.852, 95% confidence interval (95%CI) = 0.747-0.972, P = 0.017], shock before AKI (OR = 85.350, 95%CI = 5.682-1 282.073, P = 0.001), and sepsis before AKI (OR = 11.499, 95%CI = 2.127 - 62.161, P = 0.005) were independent risk factors for the judgment of prognosis. CONCLUSIONS: Shock and sepsis are the major risk factors of RRT in trauma patients with AKI. Shock, sepsis and traumatic brain injury are the independent risk factors of death. Perhaps early initiation of routine RRT cannot improve the outcome of the patients with posttraumatic renal insuficiency.


Asunto(s)
Lesión Renal Aguda , Estudios de Cohortes , Femenino , Humanos , Incidencia , Unidades de Cuidados Intensivos , Riñón , Masculino , Pronóstico , Terapia de Reemplazo Renal , Estudios Retrospectivos , Factores de Riesgo , Sepsis
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