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1.
Angew Chem Int Ed Engl ; 63(28): e202404493, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38687277

RESUMO

Timely detection of early-stage cancer holds immense potential in enhancing prognostic outcomes. There is an increasing desire for versatile tools to enable simple, sensitive, and cost-effective cancer detection. By exploiting the extraintestinal metabolic inertness and efficiency renal clearance of sucrose, we designed a liposome nanosensor using sucrose as a messenger to convert tumor-specific esterase activity into glucose meter readout, enabling economical and sensitive urinalysis for cancer detection in point-of-care testing (POCT). Our results demonstrate that the nanosensors exhibited significant signal differences between tumor-bearing and healthy mice in both orthotopic and metastatic tumor models. Additionally, efficient elimination of the nanosensors through the hepatobiliary pathway was observed with no significant toxicity. Such a non-invasive diagnostic modality significantly assists in personalized pharmacological treatment and follow-up efficacy assessment. We envision that this modular liposome nanosensor platform might be applied for economically detecting diverse diseases via a simple urinary test.


Assuntos
Lipossomos , Sacarose , Lipossomos/química , Animais , Camundongos , Sacarose/química , Sacarose/urina , Humanos , Técnicas Biossensoriais , Neoplasias/diagnóstico , Glucose/análise , Glucose/metabolismo , Urinálise
2.
Phys Chem Chem Phys ; 25(40): 27364-27372, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37791972

RESUMO

Ni-Mn based Heusler alloys have attracted widespread attention due to their novel physical properties. However, the structure of Mn2NiGa is metastable at room temperature, making it difficult to obtain its intrinsic physical properties and limiting its application. In this study, we obtained Mn2NiGa by replacing Ni in the precursor alloy Ni2MnGa with Mn and studied its magnetic properties, structures, and phase transitions with floating composition. In addition, we focused on the compositional segregation characteristics of Mn2NiGa caused by different heat treatment and quenching conditions. It was found that the samples quenched after annealing at 773 K for 48 hours exhibited abnormalities in magnetism, phase transformation, and structure. The further electron probe scanning characterization results reveal that the changes in these physical properties were related to component segregation caused by heat treatment.

3.
Phys Chem Chem Phys ; 24(40): 25010-25017, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36217967

RESUMO

Herein, Ni45-xCrxCo5Mn36.5In13.5 (x = 0, 0.2, 0.4, and 0.6 at%) and Ni45Co5Mn36.5-yCryIn13.5 (y = 0.2, 0.4, and 0.6 at%) polycrystalline Heusler alloys are prepared by arc melting and then characterized using X-ray diffraction and a vibrating sample magnetometer. A single L21 austenitic phase is confirmed at room temperature. Meanwhile, we studied the effect of Cr doping on the magnetic properties of Ni45Co5Mn36.5In13.5 alloys. It is observed that, with the incorporation of Cr atoms, both the lattice constant and valence electron concentration of the alloys have changed, resulting in the phase transition temperature, saturation magnetization and magnetic entropy changing significantly. In addition, when Cr is replaced by Mn, the change of phase transition temperature (ΔT) induced by the magnetic field decreases; therefore, in the Ni45Co5Mn36.1Cr0.4In13.5 samples, the magnetic entropy change reaches a maximum value of up to 37.1 J kg-1 K-1 under an external magnetic field of 3T, which is more than 50% higher than that of other Ni-Mn based Heusler alloys reported in the literature.

4.
Small ; 15(52): e1905446, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31782900

RESUMO

Shape-transformable liquid metal (LM) micromachines have attracted the attention of the scientific community over the past 5 years, but the inconvenience of transfer routes and the use of corrosive fuels have limited their potential applications. In this work, a shape-transformable LM micromotor that is fabricated by a simple, versatile ice-assisted transfer printing method is demonstrated, in which an ice layer is employed as a "sacrificial" substrate that can enable the direct transfer of LM micromotors to arbitrary target substrates conveniently. The resulting LM microswimmers display efficient propulsion of over 60 µm s-1 (≈3 bodylength s-1 ) under elliptically polarized magnetic fields, comparable to that of the common magnetic micro/nanomotors with rigid bodies. Moreover, these LM micromotors can undergo dramatic morphological transformation in an aqueous environment under the irradiation of an alternating magnetic field. The ability to transform the shape and efficiently propel LM microswimmers holds great promise for chemical sensing, controlled cargo transport, materials science, and even artificial intelligence in ways that are not possible with rigid-bodies microrobots.

5.
Phys Chem Chem Phys ; 21(15): 8092-8098, 2019 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-30932102

RESUMO

The correlation between the magnetocaloric effect and magnetotransport property was investigated in Ni43Co7Mn39-xCrxSn11 Heusler alloys. The asymmetric isothermal-magnetoresistance around the phase transformation temperature was observed, from which a parameter γ, determined as the ratio of the asymmetric magnetoresistance to the temperature coefficient of resistance, is proposed. According to Maxwell's equation, the parameter γ is analyzed to be equivalent to the transformation temperature change induced by a magnetic field in martensitic transformation. This finding is confirmed by experimental results. In addition, the γ values can be used to estimate the magnetic entropy change of the martensitic transformation directly without measuring the comprehensive temperature dependence of magnetization curves.

6.
J Nanosci Nanotechnol ; 19(7): 4154-4159, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30764985

RESUMO

In this study, a bubble-propelled catalytic Janus micromotor is demonstrated. This micromotor is magnetically controllable and is capable of both organics absorption and delivery. The motor is fabricated by a low-cost and eco-friendly physical method free from chemical reactions. Such a micromotor is effectively propelled by bubbles generated from hydrogen peroxide decomposition. Applied with a controlled magnetic field, the motor can travel along designed trajectories. An ultrafast travelling speed of up to 3.3 mm/s (∼320 body length) was reached in 6.3% (wt%) H2O2 solution. Additionally, Rodamine B was chosen as a target organic to proof the collection and transportation performance. The collection and release cycle of target organic is repeated for more than 25 times. This result reveals that the motor is efficient in organic absorption and transportation, indicating that the micromotor is promising in water decontamination and targeted drug delivery.

7.
Small ; 14(17): e1704546, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29611296

RESUMO

A bioinspired magnetically powered microswimmer is designed and experimentally demonstrated by mimicking the morphology of annelid worms. The structural parameters of the microswimmer, such as the surface wrinkling, can be controlled by applying prestrain on substrate for the precise fabrication and consistent performance of the microswimmers. The resulting annelid-worm-like microswimmers display efficient propulsion under an oscillating magnetic field, reaching a peak speed of ≈100 µm s-1 . The speed and directionality of the microswimmer can be readily controlled by changing the parameters of the field inputs. Additionally, it is demonstrated that the microswimmers are able to transport microparticles toward a predefined destination, although the translation velocity is inevitably reduced due to the additional hydrodynamic resistance of the microparticles. These annelid-worm-like microswimmers have excellent mobility, good maneuverability, and strong transport capacity, and they hold considerable promise for diverse biomedical, chemical sensing, and environmental applications.


Assuntos
Materiais Biomiméticos/química , Animais , Biotecnologia , Microtecnologia
8.
Nanomaterials (Basel) ; 14(9)2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38727395

RESUMO

The anomalous Hall effect and spin-orbit torque of TbCo-based multilayer films have been methodically studied in recent years. Many properties of the films can be obtained by the anomalous Hall resistance loops of the samples. We report on the effects of a structure composed of two heavy metals as the buffer layers on the anomalous Hall resistance loops of TbCo-based multilayers at different temperatures. The results showed that the coercivity increases dramatically with decreasing temperature, and the samples without perpendicular magnetic anisotropy at room temperature showed perpendicular magnetic anisotropy at low temperatures. We quantified the spin-orbit torque efficiency and Dzyaloshinskii-Moriya interaction effective field size of the films W/Pt/TbCo/Pt at room temperature by measuring the loop shift of anomalous Hall resistance. The results showed that the study of anomalous Hall resistance loops plays an important role in the study of spintronics, which can not only show the basic properties of the sample, but can also obtain other information about the sample through the shift of the loops.

9.
ACS Appl Mater Interfaces ; 16(24): 31438-31446, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38843313

RESUMO

Spin-orbit torque (SOT) has emerged as an effective means of manipulating magnetization. However, the current energy efficiency of SOT operation is inefficient due to low damping-like SOT efficiency per unit current bias. In this work, we dope conventional rare earth oxides, GdOy, into highly conductive platinum by magnetron sputtering to form a new group of spin Hall materials. A large damping-like spin-orbit torque (DL-SOT) efficiency of about 0.35 ± 0.013 is obtained in Pt0.70(GdOy)0.30 measured by the spin-torque ferromagnetic resonance (ST-FMR) technique, which is about five times that of pure Pt under the same conditions. The substantial enhancement of the spin Hall effect is revealed by theoretical analysis to be attributed to the strong side jump induced by the rare earth oxide GdOy impurities. Moreover, this large DL-SOT efficiency contributes to a low critical switching current density (8.0 × 106 A·cm-2 in the Pt0.70(GdOy)0.30 layer) in current-induced magnetization switching measurements. This systematic study on SOT switching properties suggests that Pt1-x(GdOy)x is an attractive spin current source with large DL-SOT efficiency for future SOT applications and provides another idea to regulate the spin Hall angle.

10.
Rice (N Y) ; 14(1): 23, 2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33638799

RESUMO

BACKGROUND: Zn deficiency is one of the leading public health problems in the world. Staple food crop, such as rice, cannot provide enough Zn to meet the daily dietary requirement because Zn in grain would chelate with phytic acid, which resulted in low Zn bioavailability. Breeding new rice varieties with high Zn bioavailability will be an effective, economic and sustainable strategy to alleviate human Zn deficiency. RESULTS: The high Zn density mutant LLZ was crossed with the low phytic acid mutant Os-lpa-XS110-1, and the contents of Zn and phytic acid in the brown rice were determined for the resulting progenies grown at different sites. Among the hybrid progenies, the double mutant always displayed significantly higher Zn content and lower phytic acid content in grain, leading to the lowest molar ratio of phytic acid to Zn under all environments. As assessed by in vitro digestion/Caco-2 cell model, the double mutant contained the relatively high content of bioavailable Zn in brown rice. CONCLUSIONS: Our findings suggested pyramiding breeding by a combination of high Zn density and low phytic acid is a practical and useful approach to improve Zn bioavailability in rice grain.

11.
ACS Appl Mater Interfaces ; 13(49): 58898-58907, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34851101

RESUMO

Magnetically actuated miniature robots have attracted the attention of the scientific community over the past two decades, but the confined workspace of their manipulation system (typically a tri-axial coil or eight electromagnetic coils) and the low efficiency of propulsion have limited their utility. Here, we describe a highly efficient NiFe nanorod-based magnetic miniature swimmer that can be manipulated in 3D spaces using two pairs of coils placed in the x-y horizontal plane. In the new swimmer, the shape symmetry is broken along its body, and the asymmetry in magnetizations is introduced perpendicular to the long axis of its body simultaneously. Such a combined asymmetry design offers favorable controllability in planar magnetic fields, which relaxes the multi-axial coil requirement of the commonly used manipulation system and thus reduces the restriction on the shape and size of the workspaces. The new swimmers display efficient 3D propulsion, with a speed of over 5000 µm s-1 (∼3 body length s-1) and powerful locomotion in biological media such as raw human blood. The fuel utilization efficiency of the swimmer, defined as the ratio of the distance to the net input work in one period, was estimated to be approximately from 10-2 to 10-3 m/J, which is significantly higher than that of magnetic motors with a slender body. Moreover, to provide practical support for further potential use, we demonstrated that the swimmer is able to perform incision operations as a minimally invasive microsurgical tool. Such a swimmer actuation strategy provides a simple and efficient way for 3D manipulation of magnetic miniature robots, offering great potential for future biomedical and other applications.

12.
Nat Commun ; 12(1): 1909, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33772026

RESUMO

Non-collinear magnets exhibit a rich array of dynamic properties at microwave frequencies. They can host nanometre-scale topological textures known as skyrmions, whose spin resonances are expected to be highly sensitive to their local magnetic environment. Here, we report a magnetic resonance study of an [Ir/Fe/Co/Pt] multilayer hosting Néel skyrmions at room temperature. Experiments reveal two distinct resonances of the skyrmion phase during in-plane ac excitation, with frequencies between 6-12 GHz. Complementary micromagnetic simulations indicate that the net magnetic dipole moment rotates counterclockwise (CCW) during both resonances. The magnon probability distribution for the lower-frequency resonance is localised within isolated skyrmions, unlike the higher-frequency mode which principally originates from areas between skyrmions. However, the properties of both modes depend sensitively on the out-of-plane dipolar coupling, which is controlled via the ferromagnetic layer spacing in our heterostructures. The gyrations of stable isolated skyrmions reported in this room temperature study encourage the development of new material platforms and applications based on skyrmion resonances. Moreover, our material architecture enables the resonance spectra to be tuned, thus extending the functionality of such applications over a broadband frequency range.

13.
J Nanosci Nanotechnol ; 10(12): 8452-5, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21121353

RESUMO

Unlike previous studies that emphasize the important role of thermodynamics or surface energy on the structure stabilization of ZnS nanocrystals, we successfully controlled the crystalline structure of ZnS nanocrystals simply by tuning sulfur precursor addition rate under exactly the same other conditions. We observed the structure of as prepared ZnS nanocrystals was evolved from wurtzite into zinc blende with increasing the addition rate of sulfur precursor. The method may extend to engineer other nanomaterials with desired physicochemical properties by controlling crystalline structure. On the other hand, it also makes a new approach to understand the crucial factors that determine the growth mechanism and the crystal structure of nanomaterials in theory.

14.
Complement Ther Clin Pract ; 39: 101132, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32379667

RESUMO

BACKGROUND: Patients with Coronavirus Disease 2019(COVID-19) will experience high levels of anxiety and low sleep quality due to isolation treatment. Some sleep-improving drugs may inhibit the respiratory system and worsen the condition. Prolonged bedside instruction may increase the risk of medical infections. OBJECTIVE: To investigate the effect of progressive muscle relaxation on anxiety and sleep quality of COVID-19. METHODS: In this randomized controlled clinical trial, a total of 51 patients who entered the isolation ward were included in the study and randomly divided into experimental and control groups. The experimental group used progressive muscle relaxation (PMR) technology for 30 min per day for 5 consecutive days. During this period, the control group received only routine care and treatment. Before and after the intervention, the Spielberger State-Trait Anxiety Scale (STAI) and Sleep State Self-Rating Scale (SRSS) were used to measure and record patient anxiety and sleep quality. Finally, data analysis was performed using SPSS 25.0 software. RESULTS: The average anxiety score (STAI) before intervention was not statistically significant (P = 0.730), and the average anxiety score after intervention was statistically significant (P < 0.001). The average sleep quality score (SRSS) of the two groups before intervention was not statistically significant (P = 0.838), and it was statistically significant after intervention (P < 0.001). CONCLUSION: Progressive muscle relaxation as an auxiliary method can reduce anxiety and improve sleep quality in patients with COVID-19.


Assuntos
Ansiedade , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Terapia de Relaxamento , Transtornos do Sono-Vigília , Adulto , Ansiedade/terapia , Transtornos de Ansiedade , Treinamento Autógeno , Betacoronavirus , COVID-19 , Infecções por Coronavirus/complicações , Infecções por Coronavirus/psicologia , Feminino , Humanos , Masculino , Relaxamento Muscular , Pneumonia Viral/complicações , Pneumonia Viral/psicologia , Terapia de Relaxamento/métodos , SARS-CoV-2 , Sono/fisiologia , Transtornos do Sono-Vigília/etiologia , Transtornos do Sono-Vigília/terapia
15.
J Phys Chem B ; 120(51): 13112-13117, 2016 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-27966975

RESUMO

It is a tough challenge to understand the mutual interactions among various components in aqueous solutions of inorganic mixed with organic solutes. The hydration number, nh, and critical hydration number, ncr, determined by the measurements of glass transition of the solutions, in conjunction with tracing the change in local water structure, can provide some insights into the complicated interplays in such a mixture. Here, the nh and ncr for aqueous solutions of glycerol, various chlorides, and mixtures of glycerol with a chloride are determined. The ratio of ncr/nh measures 4 for glycerol and 1.7 for all the chlorides, and for mixtures of glycerol with all of the chlorides except ZnCl2, it falls within these two extremes. Glycerol content dependence of nh and ncr reveals a rich and interesting scenario of mutual effects therein, in particular, the glycerol's replacement and sharing of hydration water with salt. In the case of ZnCl2, at most, one hydration water molecule is replaced by glycerol, and the excess glycerol molecules continuously reduce the number of glycerol molecules that share hydration water with ZnCl2. Our results can help establish a pathway for the investigation of interactions among the organic and inorganic components in aqueous solutions, which is desirable for many applications.

16.
J Phys Condens Matter ; 28(47): 476006, 2016 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-27667821

RESUMO

We have investigated the temperature and the Pt layer thickness dependence of the magnetoresistances (MRs) in Co2FeSi/Pt thin films. Based on the field dependent measurements, it can be seen that the spin-current-induced spin Hall magnetoresistance (SMR) plays the dominant role in the MRs in the Co2FeSi/Pt bilayers in the whole temperature range. Meanwhile, a quite small part of anisotropic magnetoresistance (AMR) existed in the MRs. It proved to be originated from magnetic proximity effect (MPE) by measuring the Pt thickness and temperature dependence of the AMR. Moreover, the Co2FeSi layer thickness has much weaker effect on the SMR and AMR compared to the Pt layer thickness. These results indicate that the Co2FeSi/Pt interface is beneficial to be used in the spin-current-induced physical phenomena.

17.
Biosens Bioelectron ; 69: 142-7, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25725462

RESUMO

DNA-metal nanoparticle conjugates have been increasingly exploited for sensing purposes over the past decades. However, most of the existing strategies are operated with canonical DNA structures, such as single-stranded forms, stem-loop structures, and double helix structures. There is intense interest in the development of nano-system based on high order DNA secondary structures. Herein, we propose a SERS/fluorescence dual-mode nanosensor, where the signal transduction mechanism is based on the conformational switching of the human telomeric G-quadruplex DNA. The nanosensor exhibits excellent SERS/fluorescence responses to the complementary strands of G-quadruplexes. Based on T-Hg(2+)-T coordination chemistry, this sensor is effectively applied to determination of Hg(2+) in buffer solution and real samples. It achieves a limit of detection (LOD) as low as 1ppt, which is ~100 times more sensitive than conventional optical sensors. We anticipate that the proposed G-quadruplex-based nanosensor could be applied to the analysis of other metal ions and small molecules in environmental samples and biological systems.


Assuntos
DNA/química , Mercúrio/análise , Nanopartículas Metálicas/química , Espectrometria de Fluorescência/instrumentação , Análise Espectral Raman/instrumentação , Telômero/química , Desenho de Equipamento , Análise de Falha de Equipamento , Quadruplex G , Humanos , Mercúrio/química , Nanopartículas Metálicas/ultraestrutura , Nanoconjugados/química , Nanoconjugados/ultraestrutura , Nanotecnologia/instrumentação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Telômero/genética , Poluentes Químicos da Água/análise
18.
ACS Appl Mater Interfaces ; 7(47): 26017-21, 2015 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-26580305

RESUMO

Magnetically actuated nanomotor, which swims under externally applied magnetic fields, shows great promise for controlled cargo delivery and release in biological fluids. Here, we report an on-demand release of 6-carboxyfluoresceins (FAM), a green fluorescein, from G-quadruplex DNA functionalized magnetically actuated wormlike nanomotors by applying an alternating magnetic field. This field-triggered FAM releasing process can be easily controlled by multiple parameters such as magnetic field, frequency, and exposure time. In addition, the experimental results and the theoretical simulation demonstrate that both a thermal and a nonthermal mechanism are involved in the cargo releasing process.


Assuntos
Fluoresceínas/química , Magnetismo , Nanopartículas/química , Preparações de Ação Retardada , Células HeLa , Humanos , Campos Magnéticos , Nanopartículas/ultraestrutura , Espectrometria de Fluorescência
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