Publications by authors named "Dekai Zhou"

Research on the interfacial instability of two-phase systems can help in gaining a better understanding of various hydrodynamic instabilities in nature. However, owing to the nonlinear and complex spatiotemporal dynamics of the unstable interface, the instability is challenging to control and suppress. This paper presents a novel interfacial instability of the magnetic microswarm induced by the competition between the destabilizing effect of magnetic field and the stabilizing effect of acoustic field.

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Microcantilever structures such as microgears play an important role in precision mechanisms, where highly accurate cantilever characteristics guarantee the reliable function of these structures. Projection-based stereolithography (PSL) technology is widely used to fabricate sophisticated microstructures owing to its high precision and remarkable efficiency, and plenty of works have been done to improve the precision of structures with macroscale. However, the shape accuracy of microcantilever structures fabricated through PSL process is always neglected, which severely hinders its application in precision mechanisms.

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Untethered micro/nanorobots (MNRs) show great promise in biomedicine. However, high-precision targeted navigation of MNRs into both deep and tiny microtube networks comes with big challenges because the present medical imaging cannot simultaneously meet the requirements of high resolution, high penetration depth, and high real-time performance. Inspired by intracellular motor proteins that transport cargo along cytoskeletal tracks, this study proposed a microtube inwall-guided targeted self-navigation strategy of magnetic microwheels (μ-wheels) that relies only on interactions with a microtube inwall, compared to conventional techniques that rely on real-time imaging and tracking of MNRs.

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To improve the recovery rate of oil in the formation, oil recovery technology has been continuously studied. Considering the experimental cost and data measurement in oil recovery research, laboratory oil recovery is the most effective method. The rock core model used in the simulation directly affects whether the research results are credible.

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The incidence of intestinal cancer has risen significantly. Because of the many challenges posed by the complex environment of the intestine, it is difficult to diagnose accurately and painlessly using conventional methods, which requires the development of new body-friendly diagnostic methods. Micro- and nanomotors show great potential for biomedical applications in restricted environments.

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Micromotors hold great promise for extensive practical applications such as those in biomedical domains and reservoir exploration. However, insufficient propulsion of the micromotor limits its application in crossing biological barriers and breaking reservoir boundaries. In this study, an ultrafast microbullet based on laser cavitation that can utilize the energy of a cavitation bubble and realize its own hurtling motion is reported.

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Microscale intestinal perforation can cause considerable mortality and is very difficult to treat using conventional methods owing to the numerous challenges associated with microscale operations, which require the development of new body-friendly and effective treatment methods. Swarming micro- and nanomotors have shown great potential in biomedical applications in complex and hard-to-reach environments. Herein, we present a wheel-like magnetic-driven microswarm (WLM) with a band-aid imitation to patch microscale intestinal perforations by pasting on the perforation point in mucus-filled environments.

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Living things in nature have evolved with unique morphologies, structures, materials, behaviors, and functions to survive in complex natural environments. Nature has inspired the design ideas, preparation methods, and applications of versatile micro/nanomotors. This review summarizes diverse nature-inspired micro/nanomotors, which can be divided into five groups: (i) natural morphology-inspired micro/nanomotors, whose shapes are designed to imitate the morphologies of plants, animals, and objects in nature.

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Tip-extending soft robots, taking flexible film or rubber as body material and fluid pressure as input power, exhibit excellent advantages in constrained and cluttered environments for detection and manipulation. However, existing soft continuum robots are of great challenges in achieving multiple, mutually independent, and on-demand active steering over a long distance without precise steering control. In this paper, we introduce a vine-like soft robot made up of a pressurized thin-walled vessel integrated with the high controllability of a control system with multiple degrees of freedom in three dimensions.

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As visible light accounts for a larger proportion of solar energy and is harmless to living organisms, it has the potential to be the energy source of micro/nanomotors, which transform visible-light energy into mechanical motion, for different applications, especially in environmental remediation. However, how to precisely control the motion of visible-light-driven micro/nanomotors (VLD-MNMs) and efficiently utilize the weak visible-light photon energy to acquire rapid motion are significant challenges. This review summarizes the most critical aspects, involving photoactive materials, propulsion mechanisms, control methods, and applications of VLD-MNMs, and discusses strategies to systematically enhance the energy-harvesting efficiency and adaptation.

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Kasabach-Merritt phenomenon (KMP) is a rare disease that is characterized by severe thrombocytopenia and consumptive coagulation dysfunction caused by kaposiform hemangioendothelioma or tufted hemangioma. This condition primarily occurs in infants and young children, usually with acute onset and rapid progression. This review article introduced standardized recommendations for the pathogenesis, clinical manifestation, diagnostic methods and treatment process of KMP in China, which can be used as a reference for clinical practice.

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Surface-enhanced Raman spectroscopy (SERS) is a powerful sensing technique capable of capturing ultrasensitive fingerprint signal of analytes with extremely low concentration. However, conventional SERS probes are passive nanoparticles which are usually massively applied for biochemical sensing, lacking controllability and adaptability for precise and targeted sensing at a small scale. Herein, we report a "rod-like" magnetic nanomotor-based SERS probe (MNM-SP) that integrates a mobile and controllable platform of micro-/nanomotors with a SERS sensing technique.

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Hollow mesoporous silica nanoparticles (HMSNPs) have been widely explored in the biomedical field as drug delivery nanocarriers by virtue of their large hollow cavity. However, the connectivity between the internal cavity and the outside environment by numerous nanochannels on the mesoporous shell allows for possible drug leakage, leading to nonsufficient drug loading due to unreliable capping of the nanopores. In addition, the issue of ensuring effective utilization of the hollow cavity for achieving high drug loading capacity of HMSNPs is seldom addressed.

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To assess the practicality of 3-D power Doppler angiography (3-D-CPA) for local drug perfusion dosage guidance of refractory infantile hemangioma (IH) treatment, 47 cases (48 lesions) of refractory IH were selected for local bleomycin infusion (once a month). Ultrasound was performed before treatment and 1 and 2 months after the first treatment. The 3-D volume (V) change of infantile hemangiomas and the ratio of bleomycin injection to 3-D V before treatment were calculated, and statistical analysis was performed.

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Micropump systems show great potential on the micropatterning process as a result of remarkable performance and functionality. However, existing micropumps cannot be employed as direct writing tools to perform the complex micropatterning process because of their lacking motility and controllability. Here, we propose a motile micropump system based on the combination of a water-driven ZnO/Ni/polystyrene Janus micromotor with a traditional immobilized micropump.

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The self-assembly of nanomotors is important for the production of materials with functional optical, mechanical and conductive properties. Yet, self-assembly methods are limited by their slow kinetics and limited scale. Here we report a light-induced method that yields a large-scale predefined pattern constructed by self-organization of nanomotors.

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It is of great interest and big challenge to control the collective behaviors of nanomotors to mimic the aggregation/separation behavior of biological systems. Here, a light-acoustic combined method is proposed to control the aggregation/separation of artificial nanomotors. It is shown that nanomotors aggregate at the pressure node in acoustic field and afterward present a collective "firework" separation behavior induced by light irradiation.

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Controllable locomotion in the micro-/nanoscale is challenging and attracts increasing research interest. Tubular microjets self-propelled by microbubbles are intensively investigated due to their high energy conversion efficiency, but the imperfection of the tubular geometry makes it harder to realize linear motion. Inspired by the macro rocket, we designed a tubular microjet with a grating-structured wall which mimics the guiding empennage of the macro rocket, and we found that the fluid can be effectively guided by the grooves.

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We report the synthesis and properties of rod-shaped gold/iron oxide nanomotors that are powered by visible light in dilute hydrogen peroxide solutions. Electrochemical measurements confirmed that the light-driven nanomotors operate by a self-electrophoretic mechanism, modulated by the photovoltage and the photoconductivity of gold/iron oxide. Due to the magnetism of iron oxide, the nanomotors can be steered by an external magnetic field without incorporating additional magnetic materials into the nanomotors.

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Rheotaxis is a common phenomenon in nature that refers to the directed movement of micro-organisms as a result of shear flow. The ability to mimic natural rheotaxis using synthetic micro/nanomotors adds functionality to enable their applications in biomedicine and chemistry. Here, we present a hybrid strategy that can achieve both positive and negative rheotaxis of synthetic bimetallic micromotors by employing a combination of chemical fuel and acoustic force.

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We report the fabrication of tadpole-shaped Si-Au micromotors using glancing angle deposition. These micromotors are activated by visible light and can move in either deionized water or organic solvents without the addition of chemical fuels. By controlling the light intensity, the velocity of the micromotors can be modulated and the motion can be switched on and off reversibly.

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Article Synopsis
  • - Non-selective β-blocker propranolol is FDA-approved as the primary treatment for infantile hemangioma (IH) due to its significant effectiveness.
  • - Timolol maleate has emerged as a popular alternative to propranolol, aiming to reduce systemic side effects, but there is still debate on various aspects of its use, including indications and dosage.
  • - A consensus developed by Chinese experts aims to standardize topical timolol treatment for IH, helping to minimize complications and improve clinical practices based on current evidence.
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Correction for 'Visible-light controlled catalytic CuO-Au micromotors' by Dekai Zhou, et al., Nanoscale, 2017, DOI: 10.1039/c6nr08088j.

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Visible light driven CuO-Au micromotors exhibit rapid on/off switching and speed control. Electrochemical measurements confirm that the light-induced movement of the CuO-Au micromotors involves a self-electrophoresis mechanism modulated by the photoconductivity of CuO. This study extends the utilization of the electromagnetic spectrum for micro/nanomotors into the visible range.

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Infantile hemangioma (IH) is one of the most common benign vascular tumors in children. A variety of treatment methods have been documented for the management of IH over the past years, including pharmacotherapy via oral administration or injection of corticosteroids, vincristine, alpha interferon and bleomycin; laser therapy, radionuclide therapy, cryotherapy and excisional surgery. The therapeutic efficacy of each treatment modality is variable, while adverse effects or complications are common and sometimes serious.

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