Cell–cell interaction accounts for one of the most influential factors affecting the viability and functionality of cell‐based tissue models. In this respect, various methods capable of producing ...micro‐patterns with cell spheroids are introduced to simultaneously improve contact‐dependent and ‐independent cell‐cell interactions. However, no method has yet been designed to effectively generate precise 3D patterns with multiple spheroid types. In this study, a new high‐precision and convenient 3D spheroid printing technology is developed, designated as 3D bio‐dot printing. This new technique is designed to produce cell‐laden, non‐adhesive micro‐pores within 3D structures to allow cell spheroids to be induced at printed sites. Experimental results show that various cell types, including hepatocytes, pancreatic β‐cells, and breast cancer cells, can be employed for the in situ formation of cell spheroids, and 3D freeform structures with multiple spheroid types can be printed. Moreover, this novel technology can also be used for performing 3D invasion assays. More importantly, it ensures that the precise control of spheroid size and position is achieved at micrometer scale. Finally, the usefulness of this novel technology is demonstrated by producing multicellular micro‐patterns with primary hepatocyte spheroids and endothelial cells, that exhibit significantly improved long‐term hepatic function and drug metabolism.
A new, high‐precision 3D cell spheroid printing technique, named 3D bio‐dot printing, is presented. The new technique exhibits convenient, precise, and 3D producible results with multiple cell spheroids, and can be applied to 3D spheroid invasion assays. Its application to hepatic models demonstrates that the technique can significantly improve long‐term hepatic function and drug metabolism through precise patterning with cell spheroids.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Considering the lack of antiviral drugs worldwide, we investigated the antiviral potential of fucoxanthin, an edible carotenoid purified from Sargassum siliquastrum, against zika virus (ZIKV) ...infection. The antiviral activity of fucoxanthin was assessed in ZIKV-infected Vero E6 cells, and the relevant structural characteristics were confirmed using molecular docking and molecular dynamics (MD) simulation. Fucoxanthin decreased the infectious viral particles and nonstructural protein (NS)1 mRNA expression levels at concentrations of 12.5, 25, and 50 µM in ZIKV-infected cells. Fucoxanthin also decreased the increased mRNA levels of interferon-induced proteins with tetratricopeptide repeat 1 and 2 in ZIKV-infected cells. Molecular docking simulations revealed that fucoxanthin binds to three main ZIKV proteins, including the envelope protein, NS3, and RNA-dependent RNA polymerase (RdRp), with binding energies of −151.449, −303.478, and −290.919 kcal/mol, respectively. The complex of fucoxanthin with RdRp was more stable than RdRp protein alone based on MD simulation. Further, fucoxanthin bonded to the three proteins via repeated formation and disappearance of hydrogen bonds. Overall, fucoxanthin exerts antiviral potential against ZIKV by affecting its three main proteins in a concentration-dependent manner. Thus, fucoxanthin isolated from S. siliquastrum is a potential candidate for treating zika virus infections.
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•A new bio-inspired design for PDMS sponge has been proposed to improve the absorption capacity for oil-water separation.•The concept of the water absorption and storage functions of ...cacti plant was applied in designing the PDMS sponge.•The sponge with microscale architecture was fabricated by 3D printing technology.•The new design showed an absorption capacity increased by about 3.7 times in the test of oil-water separation.
Oil spills from disasters such as the sinking of ships and the discharge of oily wastes cause serious environmental problems. Polydimethylsiloxane(PDMS) sponges are valuable tools for isolating spilled oil. Here, we propose new PDMS sponges with bio-inspired design and enhanced absorption capacities. 3D printing was used to produce templates having negative designs, and after being filled with PDMS, the templates were selectively dissolved. Through this, PDMS sponges with well-interconnected and controlled porosities were produced within 10% error. The wettability of sponges with various pore sizes and line widths was investigated. The surfaces were found to be highly hydrophobic, with water contact angles of 100-143°, and oleophilic, with oil contact angles of ∼0°. The sponge fabricated with line width of 200 μm and pore size of 400 μm showed the highest hydrophobicity and oleophilicity. These parameters were used to produce the surfaces of hollow sponges having bio-inspired design that mimics the water absorption and storage functions of cactus. Repeated oil-water separation testing was conducted, and the absorption capacities were compared with those of non-hollow and conventional sponges. The new design showed absorption capacity up to 3.7 times that of the sponges. The bio-inspired PDMS sponge provides a significant advance in oil–water separation ability.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Planar CH3NH3PbI3 perovskite solar cells with constant 17.2% average power conversion efficiency irrespective of the scan rate are described. These properties are attributed to the formation of a ...pure CH3 NH3 PbI3 thin film by the introduction of a HI solution. Thereby, charge‐injection/separation efficiency, charge‐collection efficiency, diffusion coefficient, carrier lifetime, and traps are improved.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
On the basis of recent research, brain-inspired parallel computing is considered as one of the most promising technologies for efficiently handling large amounts of informational data. In general, ...this type of parallel computing is called neuromorphic computing; it operates on the basis of hardware-neural-network (HW-NN) platforms consisting of numerous artificial synapses and neurons. Extensive research has been conducted to implement artificial synapses with characteristics required to ensure high-level performance of HW-NNs in terms of device density, energy efficiency, and learnings accuracy. Recently, artificial synapsesspecifically, diode- and transistor-type synapsesbased on various two-dimensional (2D) van der Waals (vdW) materials have been developed. Unique properties of such 2D vdW materials allow for notable improvements in synaptic performances in terms of learning capability, scalability, and power efficiency, thereby highlighting the feasibility of the 2D vdW synapses in improving the performance of HW-NNs. In this review, we introduce the desirable characteristics of artificial synapses required to ensure high-level performance of neural networks. Recent progress in research on artificial synapses, fabricated particularly using 2D vdW materials and heterostructures, is comprehensively discussed with respect to the weight-update mechanism, synaptic characteristics, power efficiency, and scalability.
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IJS, KILJ, NUK, PNG, UL, UM
Melanin synthesis is a defense mechanism that prevents skin damage, but excessive accumulation of melanin occurs in the skin in various reactions such as pigmentation, lentigines, and freckles. ...Although anti-melanogenic effects have been demonstrated for various naturally occurring marine products that inhibit and control tyrosinase activity, most studies have not been extended to in vivo applications. Phlorofucofuroeckol-A (PFF-A, 12.5-100 µM) isolated from
has previously been shown to have tyrosinase-mitigative effects in B16F10 cells, but it has not been evaluated in an in vivo model, and its underlying mechanism for anti-melanogenic effects has not been studied. In the present study, we evaluated the safety and efficacy of PFF-A for anti-melanogenic effects in an in vivo model. We selected low doses of PFF-A (1.5-15 nM) and investigated their mitigative effects on pigmentation stimulated by α-MSH in vivo and their related-mechanism in an in vitro model. The findings suggest that low-dose PFF-A derived from
suppresses pigmentation in vivo and melanogenesis in vitro. Therefore, this study presents the possibility that PFF-A could be utilized as a new anti-melanogenic agent in the cosmeceutical industries.
Background:
Given the superiority of meniscal repair over partial meniscectomy according to biomechanical data, the clinical outcomes of meniscal repair are likely to be better than those of partial ...meniscectomy for a medial meniscus root tear (MMRT).
Purpose/Hypothesis:
This review was designed to compare the clinical and radiological results between meniscal repair and partial meniscectomy for MMRTs. It was hypothesized that meniscal repair would result in better clinical and radiological results compared with partial meniscectomy.
Study Design:
Systematic review; Level of evidence, 4.
Methods:
Studies were included in the review if they (1) included patients with MMRTs who underwent primary arthroscopic meniscal repair or partial meniscectomy and (2) analyzed validated patient-reported outcomes and/or radiological evaluations. Summary odds ratios (ORs) with 95% CIs were calculated to compare partial meniscectomy with meniscal repair for each outcome.
Results:
A total of 13 studies were included. The mean duration of follow-up was 33.5 and 47.2 months in the meniscal repair group and partial meniscectomy group, respectively. The change in the Lysholm score from preoperatively to postoperatively was statistically significantly in favor of meniscal repair (OR, 2.20 95% CI, 1.55-3.12), while no difference was found with respect to the change in the Tegner score between the 2 surgical approaches (OR, 1.21 95% CI, 0.65-2.24). The prevalence of postoperative severe knee osteoarthritis (OR, 0.31 95% CI, 0.17-0.54) as well as that of reoperations (OR, 0.05 95% CI, 0.01-0.19) were significantly in favor of meniscal repair.
Conclusion
Better outcomes were seen after meniscal repair compared with partial meniscectomy for MMRTs, with greater improvements in Lysholm scores, and lower rates of progression to knee osteoarthritis, and lower reoperation rate.
This paper summarizes how Team KAIST prepared for the DARPA Robotics Challenge (DRC) Finals, especially in terms of the robot system and control strategy. To imitate the Fukushima nuclear disaster ...situation, the DRC performed eight tasks and degraded communication conditions. This competition demanded various robotic technologies, such as manipulation, mobility, telemetry, autonomy, and localization. Their systematic integration and the overall system robustness were also important issues in completing the challenge. In this sense, this paper presents a hardware and software system for the DRC‐HUBO+, a humanoid robot that was used for the DRC; it also presents control methods, such as inverse kinematics, compliance control, a walking algorithm, and a vision algorithm, all of which were implemented to accomplish the tasks. The strategies and operations for each task are briefly explained with vision algorithms. This paper summarizes what we learned from the DRC before the conclusion. In the competition, 25 international teams participated with their various robot platforms. We competed in this challenge using the DRC‐HUBO+ and won first place in the competition.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Mimicking human skin sensation such as spontaneous multimodal perception and identification/discrimination of intermixed stimuli is severely hindered by the difficulty of efficient integration of ...complex cutaneous receptor‐emulating circuitry and the lack of an appropriate protocol to discern the intermixed signals. Here, a highly stretchable cross‐reactive sensor matrix is demonstrated, which can detect, classify, and discriminate various intermixed tactile and thermal stimuli using a machine‐learning approach. Particularly, the multimodal perception ability is achieved by utilizing a learning algorithm based on the bag‐of‐words (BoW) model, where, by learning and recognizing the stimulus‐dependent 2D output image patterns, the discrimination of each stimulus in various multimodal stimuli environments is possible. In addition, the single sensor device integrated in the cross‐reactive sensor matrix exhibits multimodal detection of strain, flexion, pressure, and temperature. It is hoped that his proof‐of‐concept device with machine‐learning‐based approach will provide a versatile route to simplify the electronic skin systems with reduced architecture complexity and adaptability to various environments beyond the limitation of conventional “lock and key” approaches.
A highly stretchable cross‐reactive sensor matrix for electronic‐skin applications is demonstrated, which can detect, classify, and discriminate various intermixed tactile and thermal stimuli based on machine learning. By adopting a learning algorithm based on the bag‐of‐words model, highly accurate classification of intermixed stimuli is achieved.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Multi‐valued logic (MVL) technology that utilizes more than two logic states has recently been reconsidered because of the demand for greater power saving in current binary logic systems. Extensive ...efforts have been invested in developing MVL devices with multiple threshold voltages by adopting negative differential transconductance and resistance. In this study, a reconfigurable, multiple negative‐differential‐resistance (m‐NDR) device with an electric‐field‐induced tunability of multiple threshold voltages is reported, which comprises a BP/ReS2 heterojunction and a ReS2/h‐BN/metal capacitor. Tunability for the m‐NDR phenomenon is achieved via the resistance modulation of the ReS2 layer by electrical pulses applied to the capacitor region. Reconfigurability is verified in terms of the function of an MVL circuit composed of a reconfigurable m‐NDR device and a load transistor, wherein staggered‐type and broken‐type double peak‐NDR device operations are adopted for ternary inverter and latch circuits, respectively.
A reconfigurable, multiple negative‐differential‐resistance device with an electric‐field‐induced tunability of multiple threshold voltages is proposed. Following the successful verification of the tunability of multiple negative‐differential‐resistance phenomenon, the reconfigurability in terms of the function of multi‐valued logic circuits, from ternary inverter to latch circuit, is demonstrated.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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